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Simulations of drift resistive ballooning L-mode turbulence in the edge plasma of the DIII-D tokamaka) | Results from simulations of electromagnetic drift-resistive ballooning turbulence for tokamak edge turbulence in realistic single-null geometry are reported. The calculations are undertaken with the BOUT three-dimensional fluid code that solves Braginskii-based fluid equations [X. Q. Xu and R. H. Cohen, Contrib. Plasma Phys. 36, 158 (1998)]. The simulation setup models L-mode edge plasma parameters in the actual magnetic geometry of the DIII-D tokamak [J. L. Luxon et al., Fusion Sci. Technol. 48, 807 (2002)]. The computations track the development of drift-resistive ballooning turbulence in the edge region to saturation. Fluctuation amplitudes, fluctuation spectra, and particle and thermal fluxes are compared to experimental data near the outer midplane from Langmuir probe and beam-emission-spectroscopy for a few well-characterized L-mode discharges in DIII-D. The simulations are comprised of a suite of runs in which the physics model is varied to include more fluid fields and physics terms. The simulatio... | Abstract Mathematical modelling for a class of flexible robot with two links and three joints is considered in this paper. Assume that one of the two links is elastic and that the deformatin of the elastic link happens along any direction perpendicular to the longitudinal axis of the elastic link. Using the dynamics and Hamilton 's variational principle, we deduce that the transverse displacement (deformation) of the elastic link and the revolved angles should satisfy a system that is composed of two elastic partial differential equations of order four and three nonlinear integrodifferential equations. | eng_Latn | 4,300 |
Studies of the contribution of alternating electromagnetic fields toward material fatigue in 100Cr6 | Purpose – The purpose of this paper is to show how controlled exposure of electromagnetic fields toward bearing steel vulnerates the microstructure. The ability of Barkhausen Noise signal processing is used for detecting phenomena such as dislocation and subgrain formation processes as the beginning of later failures.Design/methodology/approach – A Barkhausen noise signal measurement equipment is used for detecting subsurface distress of 100Cr6 as a function of the applied electromagnetic and mechanical stress. Barkhausen noise signal is mathematically processed by use of fractal dimension analysis.Findings – The paper cleary reveals significant impact of electromagnetic field in junction with mechanical loading. Electromagnetic impact depends on the magnitude of the field.Research limitations/implications – Research limitations are given by the fact that in real field applications, e.g. wind power plants, bearings are exposed by multiple influences and the methodology is not applicable to those condition... | We theoretically propose a method to identify $\ifmmode\pm\else\textpm\fi{}s$-wave order parameter in recently discovered Fe-pnictide superconductors. Our idea uses the Riedel anomaly in ac-Josephson current through a $\text{SI}(\ifmmode\pm\else\textpm\fi{}\text{S})$ (single-band $s$-wave superconductor/insulator/$\ifmmode\pm\else\textpm\fi{}s$-wave two-band superconductor) junction. We show that the Riedel peak effect leads to vanishing ac-Josephson current at some values of biased voltage. This phenomenon does not occur in the case when the $\ifmmode\pm\else\textpm\fi{}s$-wave superconductor is replaced by a conventional $s$-wave one so that the observation of this vanishing Josephson current would be a clear signature of $\ifmmode\pm\else\textpm\fi{}s$-wave pairing state in Fe-pnictide superconductors. | eng_Latn | 4,301 |
Multicarrier transmitter for transmitting a plurality of spatial signal streams, multicarrier receiver, and method | Multicarrier transmitter space to encode multicarrier signals for transmission on multiple spatial channels - including the frequency coder - Frequency interleaver and space. | We report on the first direct numerical simulation of drift-Alfven wave turbulence in three-dimensional magnetic field geometries. It is found that the local metric has significant influence on instability and transport and that local shear contributes as the principal damping mechanism in low-global-shear field configurations. An example of such configurations are advanced stellarator fusion concepts. The transition from simple tokamak to stellarator geometry and effects on plasma edge turbulence and anomalous transport are investigated in flux-tube models of the equilibria and suitable interpolations. In the conclusion we outline a possible optimization in regard to turbulent transport reduction of steliarator configurations. | eng_Latn | 4,302 |
Suppression of sawtooth oscillations by lower-hybrid current drive in the ASDEX tokamak. | The sawtooth oscillations in tokamak discharges with Ohmic and neutral-beam heating could be suppressed when a large part of the plasma current was driven by lower-hybrid waves (I/sub HF//I/sub p/approx. =0.5). The stabilization is due to a flattening of the current profile j(r) and an increase of q(0) above 1. Higher central electron temperatures are obtained with neutral-beam heating if the sawteeth are stabilized. The increase in total energy content in this case was 30% higher than in the presence of sawteeth. | This paper describes the features and applications of ADAM5000TCP and ADAM5511 in control system of picosecond accelerator,and mainly recounts the skillful data processing of Kingview 6.5 used as upper-layer platform,including the linear form,database,file and bit operation.Actually experience indicates that the adoption has minimized the efforts and guaranteed the real-time character and practicability of control system. | eng_Latn | 4,303 |
Feasibility study on a high current density, large-scale superconductors by dynamic stabilization. II Stability margin. | In succession of part I of this paper, the stability margin of a tape superconductor is analysed theoretically in order to prove scientific feasibility of high current density, large-scale superconductors. As a typical example, Cu-Nb3Sn-Cu conductor is investigated: The thickness of Cu and Nb3Sn are 1mm and 50μm, respectively and the strip width is 50mm. If the critical current density of limiting stability Jc=1.29×1010A/m2 is assumed, the stability margin of pulsive field applied perpendicular to the broad face of the conductor becomes 4.9T. The thermal margin is shown to be about 5×104J/m3 when disturbances are point-like, transient nature. These results indicate that the tape conductor is stable enough to be wound into superconducting magnets. | Bliss [Bliss, C., 2008. Multiple equilibrium in the Diamond capital model. Economics Letters 100, 143–145] finds numerically that the Diamond OLG model can have uncountably many steady states. We use log preferences and show analytically that a continuum of steady states can still exist. | eng_Latn | 4,304 |
Planetary Science: What would happen if you stood on Jupiter? Would you fall into the core, since it has no physical surface? | What would happen if you stood on Jupiter? | I made a plasma vortex at my home, but why doesn't it produce a zapping sound like at time when we see sparks and does the air nearby it, ionizes? | eng_Latn | 4,305 |
Light is a high frequency electromagnetic wave. Can an LC oscillation circuit emit visible light? As we all know, light is a kind of high-frequency electromagnetic waves. Can LC oscillation circuit emit visible light? | Can an LC oscillator be used to generate visible light? The LC oscillator is most commonly used to generate radio waves for practical use and the frequency $\omega$ of the LC oscillator equals that of the electromagnetic wave so produced. So, can they in principle be used to emit visible light? The frequency of visible light is on the order of a few hundred terahertz, and the frequency of an LC oscillator is $$\omega = \frac{1}{\sqrt{LC}}$$ I admit, the product $LC$ does become very small (on the order of $10^{-30}$) when the numbers are plugged in, but making an inductor and a capacitor with small values isn't difficult, is it? | What exactly happens to the signals hitting a common mode choke? I'm trying to better understand the principles behind the common mode choke. I made a few drawings to clarify. Differential Mode Signals Differential currents (driven by differential voltages) create equal but opposite magnetic fields B in the inductor core: These magnetic fields cancel each other out, so the net flux in the core is zero. As such, these differential currents don't "feel" any impedance. Common Mode Signals In contrast, common mode currents generate equal and additive magnetic fields in the core. That's why they "feel" a high impedance, and cannot get through (or getting through means they are highly attenuated). But what exactly happens? I have several theories, which I will describe below. Common Mode Signals - Theory 1 My first thought would be that the common mode signal hits the choke and creates a magnetic flux inside. By doing this, lots of energy is lost (hysteresis and perhaps other effects) as heat. Only a small part gets through: What kind of common mode choke would behave in this particular way? "Burning up" the voltage spike seems a very desirable effect to me. Common Mode Signals - Theory 2 Perhaps the voltage spike doesn't really get the chance to build up much magnetic flux in the core, or maybe the core is simply not "lossy" enough. The voltage spike bounces off the core and turns back. Only small part gets through: Although the system on the right side of the choke is protected, the system on the left has to deal with reflected signals. Nasty things like standing waves might appear. My questions I've got a few questions for you: Do you think theory 1 or theory 2 is most plausible? Do you think certain types of common mode chokes tend to behave as described in theory 1, others like in theory 2? Perhaps both of my theories are just plain wrong. If so, what actually does happen? Please enlighten me. | eng_Latn | 4,306 |
Metal foams for electromagnetic shielding: a plasma model | Metal foams are highly versatile new materials with interesting structural and electromagnetic properties. In this work, their use in electromagnetic shielding problems is investigated. More specifically, the shielding effectiveness of an aluminium foam slab is studied on the basis of an effective medium approach. Furthermore, the suitability of using a plasma model in order to describe the electromagnetic behaviour of metal foams is demonstrated by comparison with experimental data. | Abstract In this paper finite element analysis of the large deflection behaviour of skew plates has been done. A high precision conforming triangular plate bending element has been used. The central deflection, bending and membrane stresses have been reported for simply supported and clamped rhombic plates. The variations of these quantities have been studied for different skew angles. | eng_Latn | 4,307 |
Confinement in electron cyclotron heating experiments on Doublet III | Electron Cyclotron Heating experiments have been performed on the Doublet III tokamak in the expanded boundary divertor configuration. Effective ECH heating is found even at densities twice the cutoff density, with no decrease in the global energy confinement time when the cutoff is exceeded. Analysis of the behavior of the sawteeth and of the soft x-ray emission indicates that for the overdense discharges the ECH heating is taking place near the plasma edge. A simplified transport analysis indicates that the electron thermal transport coefficient decreases a factor 2 when the heating is centrally localized. The transport analysis is confirmed by the behavior of the propagation of the heat pulse when ECH is initiated. The edge heating results in a large improvement in energy confinement over the inner two thirds of the plasma. | Abstract We present a new formulation of Chern-Simons theory on a three-dimensional lattice, with either the linear gauge group R or the finite cyclic gauge group Z N . By coupling extended objects called dumb-bells to the lattice Chern-Simons field, we obtain a model exhibiting fractional statistics in the continuum limit. Internal dumb-bell angular momenta take values consistent with their statistics. The Z N - model has a gauge-decoupled condensate. Either model can admit a Maxwell term. | eng_Latn | 4,308 |
Effect of finite boundary layer on the ionization instability in non-equilibrium MHD generators | Abstract This paper presents an investigation of the effect of boundary layer on the ionization instability in non-equilibrium MHD plasmas: the Boltzmann transfer equation has been employed in the analysis. It is concluded that the effect of finite boundary layer thickness is to reduce the growth rate. Moreover, the growth rate is not constant across the channel cross-section: it is maximum on the axis and decreases away from the axis. These effects are more pronounced at higher Hall parameters. Further, it is shown that the effect of changing the flow velocity of the gas on the growth rate is more important than the effect of changing the wall temperature. | The structure of GMA is introduced. Static displacement-force model and magnetism-machine coupling model for helping understand the magnetostriction and establishes simulation model are given. Simulation result shows that response time of machine part is slowness. It brings some disbennifit affection if minish damp. For example,exceed quantity and undulation will argument. It is important to ameliorate dynamic characteristic of the system to append a reasonable adjustor. | eng_Latn | 4,309 |
Propagation of nonlinear slow waves produced by pressure pulses along the Io flux tube | Abstract A pressure enhancement in the vicinity of Io can be created in the course of the torus plasma flow around Io due to mass loading or it can be produced by volcanic outbursts on Io. For a given magnetic flux tube crossed by Io, a pressure pulse generates two slow magnetosonic waves propagating along the tube to the southern and northern ionosphere of Jupiter. These slow waves evolve rather quickly into shocks due to a steepening mechanism with accelerated plasma flow behind the shock front. This plasma flow streaming along the Io flux tube generates a field aligned potential difference, which can reach values of 1 kV for sufficiently strong pressure pulses. Therefore, this slow mode scenario seems to contribute to the Io controlled aurora as well as to the Io controlled Jovian decameter radiation (DAM) together with the generally accepted Alfven wings model. | A solution for the early flow around an impulsively started sphere in a viscous fluid has been developed in powers of the time from the start of the motion. The boundary-layer solution considered by E. Boltze has been extended and solutions of this type have been developed to include the effect of finite Reynolds numbers. For high Reynolds numbers the time series is valid past the time when separation occurs and a number of characteristic flow properties can be calculated with reasonable accuracy. | eng_Latn | 4,310 |
The Three-dimensional Structure of Plasminostreptin, a Bacterial Protein Protease Inhibitor, at 2.8Å Resolution | The three-dimensional structure of plasminostreptin, a bacterial protein protease inhibitor from Streptomyces antifibrinolyticus, was determined at 2.8A resolution by the multiple isomorphous replacement technique. A dimer with the molecular weight of 11,402×2 was included in an asymmetric unit of the crystal. The monomer, composed of 109 amino acid residues, consisted of an antiparallel twisted β-sheet with five strands, two short helices, and irregular polypeptide-chain segments. The reactive site of plasminostreptin belonged to one of these irregular polypeptide-chain segments. The two monomers in the dimer were related by a non-crystallographic pseudo-two-fold axis, and the two β-sheets were arranged face-to-face with each other. The averaged angle between the strands of the two β-sheets was approximately 30° clockwise. In spite of 37 amino acid substitutions including the reactive site residues, the tertiary and quaternary structures of plasminostreptin were similar to those of Streptomyces subtilisi... | A new method of analyzing plasma performance over large regions of density and temperature space with time-dependent multidimensional transport codes is presented. Contour plots of global plasma parameters are shown to be a valuable tool for determining the impact of very detailed physics on plasma performance. Tokamak reactor applications illustrate the importance of plasma geometry and profile effects on both steady-state and startup behavior. | eng_Latn | 4,311 |
A New Slotted-Pipe Kicker Magnet for Bepcii Storage Ring | For the severe requirements of BEPCII injecting kicker magnets, the two schemes of low impedance kicker magnets used in other accelerator labs in the world are not adaptive to the BEPCII storage ring. A new scheme of kicker magnets proposed in this article solves the difficult problem of BEPCII kicker magnet design. And the successful construction of a prototype has demonstrated that the new scheme of kicker magnets is viable and the design of the kicker magnet structure is reasonable. | FIELD: food industry. SUBSTANCE: according to the proposed method one applies the first graphic image on the first retrievable insert and the second graphic image on the second retrievable insert. One inserts the first retrievable insert into the frame attached to the outer surface of the products cooling body. The frame and the side wall of the commercial refrigerated cabinet together form a channel ensuring the first retrievable insert engagement with the channel so that to enable sliding movement. One retrieves the first retrievable insert from the frame and inserts the second retrievable insert into the frame. EFFECT: simple and effective replacement of graphic images. 6 cl, 7 dwg | kor_Hang | 4,312 |
Plan power supply for static rectifiers | Static rectifiers are widely used for HVDC conversion and in industrial plants. Rectifiers disturb a power system by generating harmonic-frequency voltages and currents which affect power system equipment in many ways. The planning required so that a rectifier plant will have the least detrimental effect on a power system is discussed. Recommendations for total harmonic voltage are given. (LCL) | In support of the TCV experimental campaign aiming at studying H-mode plasmas with snowflake (SF) divertor, free boundary equilibrium and stability studies were performed with the SPIDER and KINX codes. Due to the high flexibility of plasma shaping capabilities of TCV, SF divertor conditions can be reached for various plasma geometries. However, at high plasma current some configurations require poloidal field (PF) coil currents close to the machine limit. This is particularly important when the equilibrium sensitivity to the edge pedestal profiles, which is higher than for standard X-point configurations, is taken into account. That is why the configuration optimization should also include the profile sensitivity study when planning the shot scenario. | eng_Latn | 4,313 |
The Thomson scattering system on the lithium tokamak experiment | The lithium tokamak experiment (LTX) is a spherical tokamak with R0=0.4m, a=0.26m, BTF∼3.4kG, IP∼400kA, and pulse length ∼0.25s. The goal of LTX is to investigate tokamak plasmas that are almost entirely surrounded by a lithium-coated plasma-facing shell conformal to the last closed magnetic flux surface. Based on previous experimental results and simulation, it is expected that the low-recycling liquid lithium surfaces will result in higher temperatures at the plasma edge, flatter overall temperature profiles, centrally peaked density profiles, and an increased confinement time. To test these predictions, the electron temperature and density profiles in LTX will be measured by a multipoint Thomson scattering system. Initially, TS measurements will be made at up to 12 simultaneous points between the plasma center and plasma edge. Later, high resolution edge measurements will be deployed to study the lithium edge physics in greater detail. Technical challenges to implementing the TS system included limited... | Abstract A numerical scheme, based upon the Kobayashi-Tranter method with certain modifications, is given for axisymmetric punch and crack problems in elasticity. The problems are reduced to solving a system of linear algebraic equations instead of a Fredholm integral equation of the second kind. A standard program thus allows the treatment of a range of different cases. The indentation of a rigid punch on an elastic layer overlying an elastic foundation is formulated in this fashion and numerical results for various cases are presented. | eng_Latn | 4,314 |
Estimates on the mean current in a sphere of plasma | Several turbulent dynamo models predict the concentration of the magnetic field in chaotic plasmas in sheets with the field vector pointing alternatively in opposite directions, which should produce strong current sheets. It is proved that if the plasma is contained in a rigid sphere with perfectly conducting boundary the geometry of these sheets must be balanced so that the mean current remains essentially bounded by the Coulomb gauged mean vector potential of the field. This magnitude remains regular even for the sharp field variations expected in a chaotic flow. For resistive plasmas the same arguments imply that the contribution to the total current of the regions near the boundary compensates the current of the central part of the sphere. | This paper presents a discharge arc model which can represent approximately both static and dynamic characteristics of a typical fluorescent lamp controlled by a power electronic circuit. The proposed model was developed from the combination and modifications of the classical Cassie and Mayr equations. The equations have been expressed in a form suitable for incorporation into circuit simulators employing the nodal analysis method of equation solving. The model has been test implemented in the PSpice circuit simulator. Simulated and experimental results appear to be in good agreement. | eng_Latn | 4,315 |
130 MM aperture quadrupoles for the LHC luminosity upgrade | Several studies for the LHC luminosity upgrade pointed out the need for low-beta quadrupoles with apertures larger than the present baseline (70 mm). In this paper we focus on the design issues of a 130 mm aperture quadrupole. We first consider the Nb-Ti option, presenting a magnetic design with the LHC dipole and quadrupole cables. We study the electromagnetic forces and we discuss the field quality constraints. For the Nb3Sn option, we sketch three designs, two based on the LARP 10 mm width cable, and one on a larger cable with the same strand. The issue of the stress induced by the e.m. forces, which is critical for the Nb3Sn, is discussed using both scaling laws and finite element models. | 4 pages.-- PACS numbers: 05.45.Xt, 87.10.+e.-- ArXiv pre-print: http://arxiv.org/abs/nlin.CD/0512009.-- Final full-text version of the paper available at: http://dx.doi.org/10.1103/PhysRevE.73.055202. | eng_Latn | 4,316 |
Anomalous transport modelling of tokamak plasmas | Theory based transport simulations of DIII-D, JET, ITER are compared to experimental data using a combination of anamolous transport models. The Multiple-mode Transport Model is calibrated to a give set of L-mode and H-mode discharges with an emphasis on testing the adequacy of anomalous flux contributions from drift/{eta}{sub i} and resistive ballooning mode theories. A survey of possible additions and/or alternatives to the model from recent theories on neoclassical MHD effects, hot ion modes, circulating electron modes, and high-m tearing modes is also included. | Background: Fanconi Aneamia is a rare genomic instability inherited syndrome. Allo-BMT for life-threatening aplastic aneamia is associated to acute toxicity and secondary tumours. Gene therapy is an attractive alternative while obstacles need to be overcome: (i) the scarcity of BM-stem cells; (ii) their flimsiness (iii) gene transfer technical limitations. | eng_Latn | 4,317 |
Spin dependent momentum distributions of proton-deuteron clusters in 3He from electron scattering on polarized 3He: Theoretical predictions | The process $\overrightarrow{^3{\rm He}}(e,e'\vec{p})d $ (or $\overrightarrow{^3{\rm He}}(e,e'\vec{d})p $) is studied theoretically in a Faddeev treatment with the aim to have access to the spin-dependent momentum distribution of ${\vec p} {\vec d} $ clusters in polarized $^3$He. Final state interactions and meson exchange currents turn out to have a strong influence in the considered kinematical regime (below the pion threshold). This precludes the direct access to the momentum distribution except for small deuteron momenta. Nevertheless, the results for the longitudinal and transverse response functions are interesting as they reflect our present day understanding of the reaction mechanism and therefore data would be very useful. | Abstract Helium glow discharge cleaning (He-GDC) is frequently applied to reduce impurities like oxygen on the plasma facing materials in many plasma confinement devices, including large helical device (LHD). However, there are few reports which evaluated the wall conditioning effect from the point of view of the microstructure of materials. In the present study, therefore, microscopic damage to metals exposed to He-GDC in LHD were examined. Large numbers of dislocation loops and very high density of bubbles with sizes of 2–20 nm were formed by exposing to He-GDC. In addition, impurity deposits composed of Fe and Cr, which seemed to be re-deposited after sputtering of the first wall (SUS316L), were formed on all specimens. These serious surface modifications seem to have a larger impact on plasma fuel recycling under main plasma discharges. Instead of restoring the wall, significant damage by He-GDC creates gas trapping sites. | eng_Latn | 4,318 |
The onset of plasma potential locking | In this paper, we provide insight into the role and impact that a positively biased electrode (anode) has on bulk plasma potential. Using two-dimensional Particle-in-Cell simulations, we investigate the plasma potential as an anode transitions from very small (“probe” mode) to large (“locking” mode). Prior theory provides some guidance on when and how this transition takes place. Initial experimental results are also compared. The simulations demonstrate that as the surface area of the anode is increased transitions in plasma potential and sheath polarity occur, consistent with experimental observations and theoretical predictions. It is expected that understanding this basic plasma behavior will be of interest to basic plasma physics communities, diagnostic developers, and plasma processing devices where control of bulk plasma potential is important. | We investigated the field-induced shift of the blue phase diffraction bands. The temperature dependence of the electrostriction tensor components is determined for the first time. In the blue phase BPI at constant field strength ${\bf E}/\!\!/~[001]$, a change of the temperature leads to a change of both the unit cell volume and its shape. The deformation of the unit cell displays a pretransitional behaviour on approaching the BPI↦BPII phase transition temperature. | eng_Latn | 4,319 |
RARE CAUSE OF CHRONIC ODYNOPHAGIA | A 63-year-old Chinese gentleman, a non-smoker with less than 5 units of alcohol intake per week, presented with persistent progressive odynophagia for 1 year with sudden onset of hoarseness for 1 month. Oral and neck examinations were normal. Flexible laryngoscopy showed left false cord fullness with reduced mobility of left vocal cord. Considering the risk factors and suggestive symptoms, a laryngeal malignancy was suspected. Contrasted-enhanced CT scan of the neck revealed a linear hyperdensed lesion measuring 3.0 cm x 0.2 cm at the left paralaryngeal space between the left vocal cord and thyroid cartilage. Further questioning revealed a positive history of fish bone ingestion 1 year prior to this presentation. He was advised for an external approach neck exploration for foreign body removal. However, with high risk of recurrent laryngeal nerve injury and possible incomplete removal of foreign body due to fibrosis, the patient opted for watchful waiting. | In order to realize an efficient ECRH and also to reduce stray radiation due to non-absorbed power during ECRH, it is necessary to excite a wave that is absorbed well near the electron cyclotron resonance. In the normal fusion magnetic field confinement machine and in the electron cyclotron frequency range, WKB approximation is valid almost all the way from antenna to the absorption region due to the large scale-length of the plasma density λn and the magnetic shear τs as compared with the local wavelength λ0. In these situation, it is well known that the O/X mode propagates as O/X mode if τs ≫ λ0. Even in these situation, if τs and λn are comparable and |1/λO−1/λX|τs ≪ 1, there still remains the question from where ”X” - or ”O” - mode become ”X” - or ”O” mode at the peripheral region. In order to simulate this situation, one dimensional full wave calculation code which solve electromagnetic wave equation under arbitrary magnetic field configuration and arbitrary density profile for a given polarization s... | yue_Hant | 4,320 |
Physics Aspects of the Dynamic Ergodic Divertor (DED) | The Dynamic Ergodic Divertor (DED) is presently being installed in the TEXTOR tokamak. It consists of 16 helical coils wound helically around the torus at the high fietd side (HFS). The perturbation currents in these coils generate predominantly islands of m=10...14 and n=4leading both to rather closed ergodic and to open laminar structures. In the "laminar mode", the DED forms a helical divertor'. 3D modelling (2D finite element/l D finite volume) of the plasma transport in the laminar zone has started. By the "dynamic" operation of the DED, the heat is deposited to a wide area and forces are transferred from the currents in the DED-coils to the plasma edge. | This paper presents direction-of-arrival estimation and adaptive beamforming for smart antenna systems. DOA estimation is based on the MUSIC algorithm for identifying the direction of the source signals incident on the sensor array comprising the smart antenna system. Adaptive beamforming achieved using the LMS algorithm for directing the main beam towards the desired source signals and generating deep nulls in the directions of interfering signals. | eng_Latn | 4,321 |
Energy confinement of high-density tokamaks | Neoclassical ion heat conduction is the major energy loss mechanism in the center of an ohmically heated high-d. tokamak discharge (n>3 * 1020 m-3). This fixes the mutual dependence of plasma quantities on the axis and leads to scaling laws for the poloidal b and energy confinement time, given the empirical fact that the pressure profile and the c.d. profile are gaussian. [on SciFinder (R)] | In the context of structural health monitoring (SHM) applications, this article first presents an example of damage detection uncertainty in a typical fiberglass woven thermoplastic plate structure with pre-embedded disbonds of various sizes and locations. A Taguchi experimental design has been implemented to statistically assess the significance of uncertainty in the performed ultrasonic NDT tests. Next, a Gaussian Process (GP)-based SHM framework has been suggested to account for such possible uncertainties in training datasets of SHM applications, and hence arriving at more robust damage systems. | eng_Latn | 4,322 |
The discharging stability of the pulsed vacuum arc deposition | The pulsed vacuum arc deposition(PVAD) is a new technique of coating,which is developed in recent decades,and have widely promising usage.But the stabiliyt of the discharging is influenced by the failure discharge and the stretching discharge,which lead to the poor quality of the film and the low efficiency of the coating.To resolve that,wto-order charging circuit is used to reduce the stretching discharge,and dipulse is used to increase the reliability of the idscharge,which can decrease the failure discharge.The experiment results which were done by using the reconstructed ion source show that the failure discharge and the stredtching discharge are reduced obviously,and the sischarge is more stable.It can be concluded that the reconstruction of the ion source is efficient,and the requirements of the coating can be needed. | A plasma CVD technology was developed that can deposit high-quality Ta20S thin film, suitable for stacked capacitor dielectric film of 64 Mbit-DRAM and beyond. Ta20S films, as thin as 30 A Si02 equivalen� thickness, deposited by this newly | eng_Latn | 4,323 |
Thermally Stable Operation of Engineering Test Reactor Tokamaks | It is desirable for the plasma operating points of future Engineering Test Reactor (ETR) tokamaks to be in parameter regimes that are inherently stable to thermal fluctuations; in other words, thermal equilibrium is maintained by properties of the power balance terms themselves without an active burn control system. Methodologies are presented for calculating thermally stable operating points and scenarios to achieve these conditions. Results are given for an ETR tokamak with major radius R/sub 0/ = 5.8 m in both the ignition and current-drive modes. Burn dynamics simulations and discussion of critical issues are also presented. The analyses are general and should be applicable to a wide variety of deuterium-tritium burning tokamaks. | A year after a tsunami triggered meltdown at a Japanese nuclear plant, New Scientist examines the knock-on effects | eng_Latn | 4,324 |
Magnetron sputtering: basic physics and application to cylindrical magnetrons | Magnetron sputtering sources can be defined as diode devices in which magnetic fields are used in concert with the cathode surface to form electron traps which are so configured that the E×B electron‐drift currents close on themselves. Coaxial cylindrical magnetron sputtering sources in which post or hollow cathodes are operated in axial magnetic fields have been reported for a number of years. However, their performance is limited by end losses. A remarkable performance is achieved when the end losses are eliminated by proper shaping of the magnetic field or by using suitably placed electron‐reflecting surfaces. High currents and sputtering rates can be obtained, nearly independent of voltage, even at low pressures. This characterizes what has been defined as the magnetron mode of operation. This paper reviews the basic principles that underly the operation of dc sputtering sources in the magnetron mode with particular emphasis on cylindrical magnetrons. The important attributes of these devices as sputt... | A series of low pressure shock experiments were conducted at the one-stage light gas gun for MB2 magnesium alloy.The resulting wave profiles containing corresponding dynamic behavior of material are obtained with VISAR technique.Using an analytical method considering interaction of elastic wave and plastic wave,low pressure Hugoniot points and US-up relation are calculated.In addition,these shots provide Hugoniot elastic limit of 0.25 GPa and spall strength of 0.83 GPa for MB2. | eng_Latn | 4,325 |
Resistive Magnetohydrodynamic Simulations of Relativistic Magnetic Reconnection | Resistive relativistic magnetohydrodynamic (RRMHD) simulations are applied to investigate the system evolution of relativistic magnetic reconnection. A time-split Harten-Lan-van Leer method is employed. Under a localized resistivity, the system exhibits a fast reconnection jet with an Alfvenic Lorentz factor inside a narrow Petschek-type exhaust. Various shock structures are resolved in and around the plasmoid such as the post-plasmoid vertical shocks and the "diamond-chain" structure due to multiple shock reflections. Under a uniform resistivity, Sweet-Parker-type reconnection slowly evolves. Under a current-dependent resistivity, plasmoids are repeatedly formed in an elongated current sheet. It is concluded that the resistivity model is of critical importance for RRMHD modeling of relativistic magnetic reconnection. | We address the problem of effectiveness of the high resolution techniques applied to the conditional model. The rationale is based on a definition of the probability of resolution of maximum likelihood estimators which is computable in the asymptotic region of operation (in SNR and/or in large number of snapshots). The application case is the multiple tones estimation problem (Doppler frequencies estimation in radar). | eng_Latn | 4,326 |
The electrical design of thick film planar filter connectors | A simple method for the design of thick-film planars is established. The minimization of the inductance inherent in the internal filter capacitor is found to be important. An insertion-loss test fixture is investigated and used to measure the insertion loss of two filters. The performance of the higher-inductance filter is not as good as that of the low-inductance filter. A regression method is used to determine the equivalent circuits of the filters. The apparent variation of filter inductance and capacitance is presented. > | Numerical modeling of dependences ``critical current -- external magnetic field'' for geometrically symmetric $0-\pi$ Josephson junctions is performed. The calculation of critical current is reduced to non-linear eigenvalue problem. The critical curve of the contact is obtained as an envelope of the bifurcation curves of different distributions of the magnetic flux. The structure of vortices in contact is observed explicitly and the dependence of the basic physical characteristics of these vortices on junction's length is explored. The comparison of numerical results and known experimental data shows good qualitative and quantitative conformity. | eng_Latn | 4,327 |
Electromagnetic instability and stopping power of plasma for relativistic electron beams | The stopping power of a plasma for a relativistic electron beam (REB) is derived by taking a Weibel-type electromagnetic instability into account in a collisionless plasma. A quasi-linear theory is developed to derive the stopping power of the plasma due to the electromagnetic instability. The wave–particle interaction by use of the renormalization theory leads to a saturation level of instability. Thus the purely growing electromagnetic instability, including the effect of the beam temperature, decides an effective stopping length of the REB in the plasma. | Industrial processes involving the manufacture of heat treatment salts such as BaCl at high pressures are becoming possible. Hence, there is a need to search for a specific form of BaCl with excellent thermal properties. Motivated by this, the potential energy surface of BaCl is extensively explored using the unbiased particle swarm-intelligence optimization algorithm to uncover a global minimum enthalpy phase of BaCl within the pressure range that was recently experimentally explored. Previously predicted phases were confirmed during the structure search. Furthermore, the orthorhombic Pnma form of BaCl is predicted to be more stable and energetically more favorable than the previously predicted R-3m phase in the pressure range of ∼10–15 GPa. The electronic and thermal properties of the newly discovered phase are extensively studied using first principles calculations. In the pressure range of interest, Pnma BaCl is metallic and nonmagnetic. More so, the solution of the Boltzmann Transport Equation unrave... | eng_Latn | 4,328 |
Transport of fast particles in turbulent fields | In light of planned ITER operation, it is important to improve understanding of fast particle behavior. This work focuses on the influence of both electrostatic and electromagnetic background microturbulent fields by studying passive fast ions in gyrokinetic turbulence simulations. Since magnetic fluctuations are the primary source of fast particle diffusion at high energies, the threshold values are investigated where this regime starts to dominate over the effects of electrostatic turbulence. Comparisons with analytical theory are presented. | This paper deals with the development of a mathematical model for very high power density actively shielded air-core superconducting (SC) machines. The interacting forces of SC coils in the actively shielded SC machine are studied using a two-dimensional analytical approach. The transfer relation methodology is employed to analyze the fully air-core SC motor that is designed to reduce the weight of the machine with actively shielded coil stator. Magnetic flux and force density distributions obtained by the proposed method are compared with those obtained from finite element analyses. The results can be considered as elements of a library of tools leading toward efficient optimization and mechanical design of actively shielded SC machines. | eng_Latn | 4,329 |
Symmetrical Progressive Erythrokeratoderma. | A case of symmetrical progressive erythrokeratoderma in a 32 year old male patient noticed at the age of 27 years has been described. | A self-similar solution, for the equatorial propagation of axisymmetric point explosion into an inhomogeneous ideal gas permeated by a current-free azimuthal magnetic field, are obtained. The model has been considered here in which the magnetic field is proportional tor−1, but the total energy of the wave is of the increasing order, not constant. | eng_Latn | 4,330 |
Influence of biased electrode on plasma confinement in the Tohoku University Heliac | Observations of an increase in electron density triggered by electrode biasing are reported in the Tohoku University Heliac (TU-Heliac). The biased electrode, which is located deep inside the plasma, induces a strong positive radial electric field, after which the line density increases by a factor of 2, the electron density profile steepens and the fluctuation level drops. We estimate the damping force opposing poloidal rotation experimentally and compare it with various versions of the neoclassical theory. The experimental results agree in that the measured damping force has a local maxima at |M p|=1–2 and tends to be proportional to M p in the high speed region (|M p|>3–6), where M p is the poloidal Mach number. For |M p|<1–2, however, the dependence of the measured damping force on M p differs a little from theoretical predictions. | Comparative measurements of the absorption edge of p‐type GaAs and compensated GaAs over a wide temperature range demonstrate that the shape of the edge in such materials is not dependent on phonon interactions, and is attributable to the state of charge of impurities in the material. | eng_Latn | 4,331 |
Flow in a metal hydride chromatographic column | The flow of hydrogen isotopes in a metal hydride chromatographic column is calculated by a one-dimensional finite difference method. The Ergun equation is used to define the gas flow; and equilibrium pressure isotherms are used to define the column holdup. Solid phase loadings are shown to move as a wave front on absorption, but remain more uniform on desorption. 3 refs., 4 figs. | As part of the LANL/VNIIEF collaboration a high velocity cylindrical liner driven Hugoniot experiment is being designed to be driven by a VNIEF Disk Explosive Magnetic (flux compression) Generator (DEMG). Several variations in drive current and liner thickness have been proposed. This presentation will describe the LANL 1D and 2D simulations used to evaluate those designs. The presentation will also propose an analysis technique to assess a high current drive systems ability to stably and optimally drive a cylindrical aluminum liner for this type of experiment. | eng_Latn | 4,332 |
Radiation Hydrodynamics of Gas‐Puff Z‐Pinch Plasmas | Non‐LTE radiation hydrodynamic numerical simulations in 1‐D and 2‐D are performed for multi‐terawatt driven argon and krypton gas puff loads. The influence of enhanced transport coefficients on the plasmas' implosion dynamics and the effects it has on the radiation yield and spectral distribution are discussed. Also presented are simulations for the performance of a krypton gas puff driven by a class of future generators. | The paper proposes a model of a space power station composed of a Curzon-Ahlborn engine driven by the heat flux supplied by a solar collector. Both design and operational optimizations are envisaged. Universal graphs are drawn for the optimum ratio between the collector and radiator area and for a non-dimensional maximum power. A brief comparison between the three usual types of mirrors (conical, parabolic cylinder and paraboloidal) is performed. The differences between the performances obtained by using a Curzon-Ahlborn and an ideal Carnot engine, respectively, are outlined. | eng_Latn | 4,333 |
Nonlinear effects associated with kinetic Alfvén wave in magnetic islands | Observations show that kinetic Alfven waves (KAWs) play a very important role in turbulence as well as in magnetic reconnection and have also been a topic of debate in the context of particle heating. In this paper, we aim to investigate the effect of magnetic islands on the dynamics of the nonlinear KAW. The formation of current sheet/coherent structures has been explored due to the propagation of the nonlinear KAW through the chain of pre-existing fully developed chain of magnetic islands. It is found that the field localization is more intense when the density perturbation due to nonlinearity and the field perturbation due to background islands are taken into account in comparison to the perturbation created by both the sources separately. Thus, it is expected that both nonlinearity and islands (reconnection generated) will aid the field localization and hence turbulence. Based on these coherent structures, we have evaluated the power spectrum and found the scaling after first breakpoint to be consiste... | Abstract Some Icelandic concreting materials undergo alkali-aggregate reaction when used with high alkali cement. Due to the low average temperatures in Iceland, the risk of alkali expansion is diminished. Sufficient quantity of Icelandic natural pozzolans can prevent damaging expansion in concretes with reactive aggregates. | eng_Latn | 4,334 |
A chain rule in \(L^{1}\left({\operatorname*{div};\Omega}\right)\) and its applications to lower semicontinuity | A chain rule in the space \(L^{1}\left(\operatorname*{div};\Omega\right) \) is obtained under weak regularity conditions. This chain rule has important applications in the study of lower semicontinuity problems for general functionals of the form \(\int_{\Omega}f(x,u,\nabla u) dx\) with respect to strong convergence in \(L^{1}\left(\Omega\right) \) . Classical results of Serrin and of De Giorgi, Buttazzo and Dal Maso are extended and generalized. | As part of the LANL/VNIIEF collaboration a high velocity cylindrical liner driven Hugoniot experiment is being designed to be driven by a VNIEF Disk Explosive Magnetic (flux compression) Generator (DEMG). Several variations in drive current and liner thickness have been proposed. This presentation will describe the LANL 1D and 2D simulations used to evaluate those designs. The presentation will also propose an analysis technique to assess a high current drive systems ability to stably and optimally drive a cylindrical aluminum liner for this type of experiment. | eng_Latn | 4,335 |
Superfluid and unconventional superconductors | Abstract The properties of superfluid 3 He as a well-studied model system of unconventional superfluidity are reviewed. This will include a discussion of BCS theory extended to spin triplet p-wave states, the nodal structure of the energy spectrum and its implications for the thermodynamic and transport properties. Similarities with the model states proposed for the heavy fermion and high T c cuprate superconductors will be pointed out. Then, the existence of textures, vortices and other topological defects in the order parameter field of s- 3 He is discussed and contrasted with unconventional superconductivity in metals. Order parameter collective modes in s- 3 He and their possible counterparts in superconductors are considered. The role of the electric charge in superconductors and its coupling to the electromagnetic field will be analyzed. The last part will cover some recent results on nonlocal and nonlinear corrections to the magnetic penetration depth. | Abstract : The report contains a brief analysis of the following items: (a) Two-dimensional steady flow (variational method), (b) One-dimensional unsteady flow (variational method), (c) Plasma with finite conductivity (exact solutions), (d) Approximate solutions and linearized equations, (e) New numerical methods, (f) Low conductivity plasma, (g) Applications, (h) Plasma acceleration and MHD power generation. A detailed discussion of future plans is given. (Author) | eng_Latn | 4,336 |
Fusion reactor plasma-performance modeling: POPCON analysis | A new method of analyzing plasma performance over large regions of density and temperature space with time-dependent multidimensional transport codes is presented. Contour plots of global plasma parameters are shown to be a valuable tool for determining the impact of very detailed physics on plasma performance. Tokamak reactor applications illustrate the importance of plasma geometry and profile effects on both steady-state and startup behavior. | The fuel oil system and its problems in Zhanjiang Power Plant are summarized in this paper. The application of KMY bubble atomization combustion technology is discussed together with its social and economical benefits. | eng_Latn | 4,337 |
Microscopic damage of materials exposed to glow discharge cleanings in LHD | Abstract Helium glow discharge cleaning (He-GDC) is frequently applied to reduce impurities like oxygen on the plasma facing materials in many plasma confinement devices, including large helical device (LHD). However, there are few reports which evaluated the wall conditioning effect from the point of view of the microstructure of materials. In the present study, therefore, microscopic damage to metals exposed to He-GDC in LHD were examined. Large numbers of dislocation loops and very high density of bubbles with sizes of 2–20 nm were formed by exposing to He-GDC. In addition, impurity deposits composed of Fe and Cr, which seemed to be re-deposited after sputtering of the first wall (SUS316L), were formed on all specimens. These serious surface modifications seem to have a larger impact on plasma fuel recycling under main plasma discharges. Instead of restoring the wall, significant damage by He-GDC creates gas trapping sites. | This paper briefly introduced the generation,preventive methods and the experience feedback learned from foreign nuclear power stations about electromagnetic-disturbance.At the same time,considering the results of electromagnetic-disturbance test on the site of Ling-ao Nuclear Power Station(I),this paper analyzed the effect of electromagnetic equipments in Daya bay base on the sensitive instrument equipments,and proposed some advices. | eng_Latn | 4,338 |
Optimization of the snowflake diverted equilibria in the TCV tokamak | In support of the TCV experimental campaign aiming at studying H-mode plasmas with snowflake (SF) divertor, free boundary equilibrium and stability studies were performed with the SPIDER and KINX codes. Due to the high flexibility of plasma shaping capabilities of TCV, SF divertor conditions can be reached for various plasma geometries. However, at high plasma current some configurations require poloidal field (PF) coil currents close to the machine limit. This is particularly important when the equilibrium sensitivity to the edge pedestal profiles, which is higher than for standard X-point configurations, is taken into account. That is why the configuration optimization should also include the profile sensitivity study when planning the shot scenario. | Conditions are derived for the construction of total variation diminishing difference schemes with multi-point support. These conditions, which are proved for explicit, implicit, and semi-discrete schemes, correspond in a general sense to the introduction of upwind biasing. | eng_Latn | 4,339 |
Dust-Acoustic Shock Waves in a Self-Gravitating Opposite Polarity Dusty Plasmas With Trapped Ions | The basic characteristics of dust-acoustic (DA) shock waves (DASHWs) in self-gravitating dusty plasmas containing massive dust of opposite polarity, trapped ions, and Boltzmann electrons has been studied. The reductive perturbation technique has been employed to derive standard modified Burgers equation (mBE). The basic properties (viz., amplitude, width, and speed) of small but finite-amplitude DASHWs are significantly modified by the combined effects of positively and negatively charged dust component, self-gravitational force, and trapped ions. The implication of our investigation can be very effective for understanding and studying the nonlinear characteristics of the DA waves (DAWs) in laboratory and space dusty plasmas. | In this paper a study for very high efficiency targeting 99 % range converter is described. We have proposed a new soft switching boost type chopper based on snubber assisted zero voltage and zero current transition (SAZZ) with output diode fabricated “SiC schottky diode”. The output power of 8 kW with the efficiency of 98.96% was obtained. The loss breakdown evaluation of SiC-SAZZ is discussed. | eng_Latn | 4,340 |
Peculiarities of Distribution of Electromagnetic and Hydrodynamic Fields for Conductive Electric Current Treatment of Melts in Different Modes | The peculiarities of the redistribution of electromagnetic and hydrodynamic fields for conductive electric current treatment in different modes and with various electrode systems are shown. Mathematical simulation is performed to determine that, depending on the type of the electrode system and the mode of the electric current passing through the melt, qualitatively different configurations and distributions of electric, magnetic, and hydrodynamic fields are realized in the macrovolume of the melt. The character of the distribution determines the area and degree of the impact on the object under treatment, which is decisive in the design of technologies for the electric current treatment of melts. | In the following lines we present a method for the computation of the characteristic values of the parameter contained in linear differential equations. This method is applicable in certain cases when the equation cannot be reduced to the hypergeometric type. As the special example with which to illustrate our procedure we select the motion of an electron in the combined fields of a nucleus and of a magnetic dipole attached to this nucleus. This problem has an interesting bearing on the theory of the spinning electron, as will be fully discussed in section 6. | eng_Latn | 4,341 |
Linear design considerations for TO-10 candidate experiment | As part of the LANL/VNIIEF collaboration a high velocity cylindrical liner driven Hugoniot experiment is being designed to be driven by a VNIEF Disk Explosive Magnetic (flux compression) Generator (DEMG). Several variations in drive current and liner thickness have been proposed. This presentation will describe the LANL 1D and 2D simulations used to evaluate those designs. The presentation will also propose an analysis technique to assess a high current drive systems ability to stably and optimally drive a cylindrical aluminum liner for this type of experiment. | The main result of this paper identities certain derived cones to the reachable sets of nonsmooth control systems in terms of quasitangent variational inclusions that generalize the classical variational equation in the theory of O.D.E.. This result extends to nonsmooth control systems an earlier result of the second author. | eng_Latn | 4,342 |
Pulsated convective MHD flow with Hall current, heat source and viscous dissipation along a vertical porous plate | The convective MHD flow past a uniformly moving infinite vertical porous plate with Hall current, viscous dissipation, heat source and variable suction has been analyzed. The free stream velocity oscillates about a mean value. A pulsated suction is taken into account. Analytical solutions are obtained using perturbation method. The effects of Hall current over primary velocity, secondary velocity, and heat transfer amplitude and phase are analyzed. Effects of heat source parameter, Eckert number, and Prandtl number on the velocity components and temperature are also examined. | Dynamical properties of hole carriers introduced in the strongly correlated electron systems, i.e. the Mott-Hubbard insulators, are theoretically studied by using both the moment method and the operator transformation method. Particular emphasis is put on effects of the quantum spin fluctuation on the dynamics. | eng_Latn | 4,343 |
Non-inductive current drive using second harmonic electron cyclotron waves on the WT-3 tokamak | A plasma current of up to 70 kA has been sustained in WT-3 discharges by second harmonic (2Ωe) electron cyclotron (EC) waves alone, with zero loop voltage, after shutting off the Ohmic heating power. Further, in the case of high power EC wave injection, ramp-up discharges have been obtained. Pulse height analysis of hard X-rays in the line of sight at various angles to the toroidal field shows that the velocity distribution function of the high energy tail electrons is asymmetric in the toroidal direction. The 2Ωe EC wave is mainly absorbed by the tail electrons, and a 2Ωe EC driven current is generated by enhancing the asymmetry of the distribution. The figure of merit of 2Ωe EC current drive (ECCD) is ηEC(2) = (3.2-6.4) × 10−2 (1019 A/Wm2), which is one order of magnitude smaller than that of lower hybrid current drive in WT-3. This low value of ηEC(2) can be attributed to low confinement of the current carrying, high energy tail electrons produced by 2Ωe ECCD. | Warp yarns in their different applications during weaving processes are often required to support loads, either in a static manner (simple tensile) or in a dynamic one (fatigue). For this reason, the investigation into the variations of the mechanical behavior of warp yarns during weaving condition is important. The purpose of this investigation was to simulate the cyclic loading of weaving process on filament warp yarns and report their fatigue behavior. In this study, the general characterization analysis of three types of the most ordinary filament yarns, polyester, polypropylene and nylon, was performed and then their fatigue behavior was simulated as warp yarns under cyclic loading by using the dynamic mechanical analyzer (DMA 2980). For this simulation, by looking at the conditions of the most common weaving looms, two sets of frequencies as loom speed and two sets of strains as loom geometry were chosen. The relevant variations of the yarn elongation, yarn stress, yarn storage modulus, yarn loss mo... | eng_Latn | 4,344 |
Linear tearing modes calculation for diverted tokamak configurations | Writing the expression of the potential energy in terms of the perturbation of the flux function, and performing an Euler minimization, one obtains a system of ordinary differential equations in that perturbation. For a diverted configuration, the usual vanishing boundary conditions for the perturbed flux function at the magnetic axis and at infinity can no longer be used. An approach to fix “natural” boundary conditions for the perturbed flux function just at the plasma boundary has been developed; this replaces the vanishing boundary conditions at infinity. To obtain the necessary metric coefficients from an equilibrium solver, a function exhibiting the same singularity at the X point has been introduced, and thus the separatrix contour was described by a reduced number of moments. | Conditions are derived for the construction of total variation diminishing difference schemes with multi-point support. These conditions, which are proved for explicit, implicit, and semi-discrete schemes, correspond in a general sense to the introduction of upwind biasing. | eng_Latn | 4,345 |
Controlling the Plasma Potential Distribution in Segmented-Electrode Hall Thruster | Segmented electrodes and ceramic spacers (CSs) placed along the Hall thruster channel are shown to produce strong modifications of axial and radial plasma potential distributions as compared to conventional non segmented thruster. These modifications are associated with differences in secondary-electron-emission properties of materials used for electrodes and CSs and correlate with plasma-plume divergence. | This work was supported by the UK Engineering and Physical Sciences Research Council (EPSRC) grant EP/K02924X/1. E.O.R. is supported by an EPSRC DTA studentship (University of Cambridge), and F.D.D. is supported by the Honorary Vice-Chancellor’s Award and a Qualcomm/DTA Studentship. | eng_Latn | 4,346 |
Design of Nonlinear Transmission Lines Comb Generator | A comb generator is designed based the theory of harmonic generation of nonlinear transmission lines(NLTL)and the theory of soliton wave.To simulate the comb generator,the gradually scaled nonlinear transmission lines are used consisting of five segments which have different Bragg cutoff frequency.The test results show that the output power of tenth Harmonic is 4.2dBm.Compared to conventional ways of multiplier,this way has the advantages of bigger output power of higher harmonic,the sample circuit structure,debug easily,and so on. | Abstract Reducing the specimen-probe spacing to increase the sensitivity of measurement of weak remanence in geological samples, etc. introduces potential inaccuracies. These are analysed by comparing the field distributions derived for transversely magnetized cylinders with those for dipoles and for nulling coils. An optimum coil geometry is found. | eng_Latn | 4,347 |
Operational characteristics and discharge mechanisms of quasisteady magnetoplasmadynamic(MPD) arcjet for space propulsion. | Experimental researches on the operational performance and the arc structure of a quasisteady magnetoplasmadynamic (MPD) arcjet was made to develop a high-performanceaccelerator in space. The results showed that the current pattern, which depended strongly on gas species and discharge current levels, influenced the thruster performance. It was found that the plasma produced in the discharge chamber was compressed radially and that 50% on the input power was consumed in the cathode region. From the plasma potential distribution, a positive voltage slope and mass starvation were found to be present near the anode surface beyond the predicted critical current level. | Microwave-driven smart material actuators were first envisioned and developed as the best option to simplify the complexity and weight of hard wired networked power and control for smart actuator arrays. A power allocation and distribution scheme (PAD) was originally devised to simplify the wiring of thousands of control cables. The original design was limited to 20 volts, the maximum drain-source voltage of a dual-gate MOSFET used in the circuit. The present research sought to extend the usable voltage range to 200 volts. | eng_Latn | 4,348 |
Semi-empirical Evaluation of the Plasma Internal Inductance in Tokamaks | In this paper we presented an analytical and experimental approach for measurement of the plasma internal inductance in IR-T1 tokamak. For this purpose, a diamagnetic loop with its compensation coil, and also an array of magnetic probes were designed, constructed, and installed on outer surface of the IR-T1 tokamak chamber, and the poloidal beta and the Shafranov parameter and then the internal inductance measured. Moreover, a few approximate values of the internal inductance for different possible profiles of the plasma current density are also calculated. | This chapter contains sections titled: Introduction Identification of the Best Linear Approximation Using Random Excitations Generation of Uncertainty Bounds? Identification of the Best Linear Approximation Using Periodic Excitations Advises and Conclusions ]]> | eng_Latn | 4,349 |
Design and Main Parameters of the High Energy Booster Quadrupole Cold Mass for the SSC | CEA/Saclay has a long standing tradition in the area of High Energy Physics, both in equipement and experiments. In the field of Superconducting magnets for accelerators, one can recall the HERA Superconducting quadrupoles1, and the work presently being made on the LHC Superconducting quadrupoles2. | A parasitic compensated single amplifier SC biquadratic filter exactly equivalent to Fleischer-Laker two-OA biquad is described. | eng_Latn | 4,350 |
Giant sawtooth oscillations in the Doublet III tokamak | Large-amplitude sawtooth oscillations have been observed in the soft-X-ray emission, central electron temperature, neutron production rate, radiated power, Dα emission, fast-neutral flux and one-turn voltage during beam-heating experiments in the Doublet III tokamak. The necessary conditions for the appearance of giant sawteeth seem to be operation at low qa and high βT. Many features of the giant sawteeth have been simulated with a transport code to which a sawtooth mixing model and several diagnostic models were added. Substantial redistribution of particles and energy evidently occurs over the plasma interior. Global energy confinement, however, is only moderately degraded by the sawteeth. | This study investigates the effects of Pierson-Moskowitz, Jonswap spectrum that are typical irregular wave spectrums for wind turbine system with jacket support structure. Also various offshore environmental parameters based on korean local condition were used in our study. The loads acting on the system was considered by referring to the Design Load Case from IEC guide line. And improved von Karman model was used as a turbulence model. As a result, various significant wave height and peak spectral period cause noticeable difference of extreme and fatigue loads prediction. | eng_Latn | 4,351 |
Magnetic Field Variation Caused by Rotational Speed Change in a Magnetohydrodynamic Dynamo | We have performed numerical magnetohydrodynamic dynamo simulations in a spherical shell with rotational speed or length-of-day (LOD) variation, which is motivated by correlations between geomagnetic field and climatic variations with ice and non-ice ages. The results show that LOD variation leads to magnetic field variation whose amplitude is considerably larger than that of LOD variation. The heat flux at the outer sphere and the zonal flow also change. The mechanism of the magnetic field variation due to LOD variation is also found. The keys are changes of dynamo activity and Joule heating. | Abstract Mathematical modelling for a class of flexible robot with two links and three joints is considered in this paper. Assume that one of the two links is elastic and that the deformatin of the elastic link happens along any direction perpendicular to the longitudinal axis of the elastic link. Using the dynamics and Hamilton 's variational principle, we deduce that the transverse displacement (deformation) of the elastic link and the revolved angles should satisfy a system that is composed of two elastic partial differential equations of order four and three nonlinear integrodifferential equations. | eng_Latn | 4,352 |
Overview of nonlinear theory of kinetically driven instabilities | An overview is presented of the theory for the nonlinear behavior of instabilities driven by the resonant wave particle interaction. The approach should be applicable to a wide variety of kinetic systems in magnetic fusion devices and accelerators. Here the authors emphasize application to Alfven were driven instability, and the principles of the theory are used to interpret experimental data. | A new version of the noncoherent method for estimating the signal/noise parameter β K of the ionospheric signal (IS) is proposed. The comparative analysis is performed, and it is shown that the analytical (relative) accuracy of determination of β K by the new method exceeds the accuracy of a widely used standard procedure by an order of magnitude and has the same order as the accuracy of the known coherent procedure. | eng_Latn | 4,353 |
Modes of perturbation of a diffuse linear pinch: the Bessel function model | The low frequency wave and instability spectrum of a cylindrical, uniform density, zero beta plasma in a Bessel function magnetic field is analysed. The analysis has application to wave heating of reversed field pinches and energy propagation in, and instabilities of, twisted solar coronal loops. A surface Alfven wave which can be Alfven resonance damped is identified, and its connection to the unstable external kink mode is discussed. A distinctive extra mode is identified as a poloidal fast Alfven wave with wave fields concentrated at the position of zero axial equilibrium magnetic field and with a dispersion relation dependent dominantly on the poloidal wavenumber and only weakly on the axial wavenumber. Finally, the spectrum of discrete Alfven waves, or global Alfven eigenmodes, is also identified. | In this paper, a numerical method is given for solving fuzzy Fredholm integral equations of the second kind, by using Bernstein piecewise polynomial, whose coefficients determined through solving dual fuzzy linear system. Numerical examples are presented to illustrate the proposed method, whose calculations were implemented by using the Computer software MathCadV.14. | eng_Latn | 4,354 |
Electric and magnetic fields of 50 Hz are not associated with sudden infant death syndrome | Sudden infant death syndrome (SIDS) is a multifactorial condition. Power frequency magnetic fields have been implicated in SIDS. Through the use of a case-control study measuring 50 Hz electric and magnetic fields at the SIDS baby's last head position, no association could be found between SIDS and either electric (p = 0.327) or magnetic (p = 0.827) 50 Hz fields. | In support of the TCV experimental campaign aiming at studying H-mode plasmas with snowflake (SF) divertor, free boundary equilibrium and stability studies were performed with the SPIDER and KINX codes. Due to the high flexibility of plasma shaping capabilities of TCV, SF divertor conditions can be reached for various plasma geometries. However, at high plasma current some configurations require poloidal field (PF) coil currents close to the machine limit. This is particularly important when the equilibrium sensitivity to the edge pedestal profiles, which is higher than for standard X-point configurations, is taken into account. That is why the configuration optimization should also include the profile sensitivity study when planning the shot scenario. | eng_Latn | 4,355 |
On a Ballistic Method for Double Layer Regeneration in a Vlasov-Poisson Plasma | Double layers generated by a current‐driven instability are usually alive for only a short time and destroyed by emitting solitons and other nonlinear waves. It is analytically shown that they can be regenerated in a one‐dimensional Vlasov–Poisson plasma system where the upstream velocity distribution is swiftly heated to restore an unstable condition in the downstream region due to ballistic deformation. | In this paper, we consider the second order wave equation discretized in space by summation-by-parts-simultaneous approximation term (SBP-SAT) technique. Special emphasis is placed on the accuracy analysis of the treatment of the Dirichlet boundary condition and of the grid interface condition. The result shows that a boundary or grid interface closure with truncation error $\mathcal{O}(h^p)$ converges of order $p + 2$ if the penalty parameters are chosen carefully. We show that stability does not automatically yield a gain of two orders in convergence rate. The accuracy analysis is verified by numerical experiments. | eng_Latn | 4,356 |
Modeling of Surface-Wave-Sustained Plasmas in Static Magnetic Fields: A Tool for the Study of Magnetically Assisted HF Plasmas | It is now well recognized that magnetically assisted high frequency (HF) plasmas exhibit a number of characteristics that are of interest for thin film deposition or for the reproduction of narrow patterning during the fabrication of electronic components. Such plasma reactors are now in use in Japanese factories but there are still open questions concerning pattern profiles, selectivity and rate of processes, uniformity, rate and damage control of the surfaces treated. Clearly, additional research work is required before the long term viability of such machines be definitely proven. | A new multi-sensor optimal information fusion criterion weighted by scalars is presented in the linear minimum variance sense. The criterion considers the correlation among local estimate errors, and only computing the weighted scalar coefficients is needed. Therefore the computational burden can obviously be reduced, and it is convenient to apply in real time. Using steady-state Kalman filtering theory, a multi-sensor optimal information fusion steady-state Kalman filter is given based on this fusion criterion. The information fusion steady-state filter can be obtained only by one time fusing after all local filters enter steady states. Simulation example shows the effectiveness of the proposed method. | eng_Latn | 4,357 |
[Effect of purified pre-beta 1 HDL on efflux of 3H-cholesterol loaded in human smooth muscle cells]. | OBJECTIVE ::: To compare the effects of different HDL subclasses on the efflux of 3H-cholesterol loaded human smooth muscle cells (SMCS). ::: ::: ::: METHODS ::: 3H-cholesterol loaded human SMCS were incubated with purified pre-beta 1 HDL, alpha-HDL and apoE-deficient HDL3 respectively. The cholesterol effluxing capacity and incubating time of different HDL subclasses were detected, and were analysed by double-reciprocal mapping. ::: ::: ::: RESULTS ::: It was found that the value of Emax of pre-beta 1 HDL is higher than that of alpha-HDL and apoE-deficient HDL3 (P < 0.01), and the value of Ke of pre-beta 1 HDL is lower than that of alpha-HDL and apoE-deficient HDL3 (P < 0.01). ::: ::: ::: CONCLUSION ::: The results showed the effluxing capacity and efficiency of pre-beta 1 HDL were greater than those of alpha-HDL and apoE-deficient HDL3, thus suggesting that pre-beta 1 HDL is a more efficient acceptor of cell-derived 3H-cholesterol. | In this paper, the steady magnetohydrodynamic (MHD) mixed convection boundary layer flow of an incompressible, viscous and electrically conducting fluid over a stretching vertical flat plate is theoretically investigated with Hall effects taken into account. The governing equations are solved numerically using an implicit finite-difference scheme known as the Keller-box method. The effects of the magnetic parameter, the Hall parameter and the buoyancy parameter on the velocity profiles, the cross flow velocity profiles and the temperature profiles are presented graphically and discussed. Investigated results indicate that the Hall effect on the temperature is small, and the magnetic field and Hall currents produce opposite effects on the shear stress and the heat transfer at the stretching surface. | eng_Latn | 4,358 |
MHD stability in a nonparaxial open system with ring-shaped mirrors | The flute stability of a low-pressure plasma in a system containing end confinement systems, formed on the side away from the axis, in necks with a divergent magnetic flux, is analyzed. When a confinement system of this sort is combined with a ''steep'' mirror system in which a certain layer is stable with respect to the ''first'' flute mode, stability is achieved for all modes. | In an earlier paper by the author the problem of determining the optimum symmetrical weighting factors for a video MTI radar was discussed. This paper extends this work so as to remove the symmetrical restriction from the problem. In addition, for a staggered pulse system, optimum times of transmission are determined. In the earlier paper a global solution to the restricted optimization problem was achieved. In this paper only a locally optimum solution is achieved for the more general problem. | eng_Latn | 4,359 |
Effect of hydrogen on the magnetic properties of Y2Fe14B | The effects of hydrogen on the intrinsic magnetic properties (saturation magnetization, anisotropy, Mossbauer spectra) of Y2Fe14BHx are studied for 0⩽x⩽3.37. The increase in Curie temperature, dTc/dx⋍30 K for x<1, is related to a slight increase in iron moment on hydrogenation. there is a sharp fall in the anisotropy constant K1 which is partly offset at 4.2 K by a rise in K2. An important part of the anisotropy arises from iron sites belonging to the (Y,Fe)4 tetrahedra which are occupied by hydrogen. | As part of the LANL/VNIIEF collaboration a high velocity cylindrical liner driven Hugoniot experiment is being designed to be driven by a VNIEF Disk Explosive Magnetic (flux compression) Generator (DEMG). Several variations in drive current and liner thickness have been proposed. This presentation will describe the LANL 1D and 2D simulations used to evaluate those designs. The presentation will also propose an analysis technique to assess a high current drive systems ability to stably and optimally drive a cylindrical aluminum liner for this type of experiment. | eng_Latn | 4,360 |
What is "Meissner effect" Use for?? | It is not really of great practical use because it only occurs with superconductors, most effectively with type 1 supercondustors which have to be cooled to around -265 Centigrade. This is not very practical. The Meissner effect is also quenched by large magnetic fields. | YES. Mitchell & Ness could tell you. \nThey are a very reputable business. \nTheir products are outstanding.\nCheck them out.\nhttp://home.mitchellandness.com/mn/home.html | eng_Latn | 4,361 |
If plasma (4th stage of matter) can be controlled by thermo, magnetic or electro fields, just what are examples of how it's done by/with each?\n\nI'm trying to understand practical (even theoretical) applications for plasma but with a little bit of a layman's explanation. Not just the "what" but a brief explanation of the "how." \n\nI'm also wanting examples in labs or controlled environments, not outer space. Thanks! | Well most plasmoids are charged, since they are ionic in nature, allowing for fairly easy control via electromagnetic fields.\n\nEasiest practical example is a plasma torch (also called a plasma cutter) used in the steel industry. A VERY powerful electric arc is created at the front end of a nozzle through which a very powerful jet of air runs. The high energy turns the air into plasma which can then be used to cut through solid steel like a knife through butter | Monkeys, dogs, rabbits, and mice are just a few of the animals used in research. Wikipedia.org has a very comprehensive article detailing the types of animal and tests performed on them. An example: rabbits were used to test mascara and eye since their eyes didn't tear, IAMS uses dogs to test new foods. Peta.org is also a good resource since they are trying to stop animal testing. http://en.wikipedia.org/wiki/Animal_testing | eng_Latn | 4,362 |
what is icp-ms used for | Inductively coupled plasma (ICP) mass spectrometry (MS) is routinely used in many diverse research fields such as earth, environmental, life and forensic sciences and in food, material, chemical, semiconductor and nuclear industries. | An inductively coupled plasma (ICP) is a type of plasma source. Electromagnetic induction creates energy in the source by causing ions to circulate. Movement of the ions generates energy in the form of heat.peration [change | change source]. Inductively coupled plasma sources usually use argon as a fuel. Unfortunately, most ICP sources require at least 5 L/min of argon. This makes inductively coupled plasma a rather expensive source. | eng_Latn | 4,363 |
what are the characteristics of plasma | A plasma is a hot ionized gas consisting of approximately equal numbers of positively charged ions and negatively charged electrons. The characteristics of plasmas are significantly different from those of ordinary neutral gases so that plasmas are considered a distinct fourth state of matter.. | A plasma is more like a gas than any of the other states of matter because the atoms are not in constant contact with each other, but it behaves differently from a gas. It has what scientists call collective behavior. | eng_Latn | 4,364 |
Pedestal break-point formation of fusion plasma profiles - a possible tool for diagnostics | An analysis is made of the central expansion form of solution for a nonlinear reaction-diffusion equation in order to determine the break-point (knee) in the profile of a bounded fusion plasma. A suggestion is made of using the break-point as a check-point for numerical studies or as a tool for diagnostic purposes. | In this paper, we have presented an effective yield improvement methodology that can help both manufacturing ::: foundries, fabless and fab-lite companies to identify systematic failures. It uses the physical addresses of failing bits ::: from wafer sort results to overlay to inline wafer defect inspection locations. The inline defect patterns or the design ::: patterns where overlay results showed matches were extracted and grouped by feature similarity or cell names. The potentially problematic design patterns can be obtained and used for design debug and process improvement. | eng_Latn | 4,365 |
Plasma Wake Accelerators: Introduction and Historical Overview | Fundamental questions on the nature of matter and energy have found answers thanks to the use of particle accelerators. Societal applications, such as cancer treatment or cancer imaging, illustrate the impact of accelerators in our current life. Today, accelerators use metallic cavities that sustain electricfields with values limited to about 100 MV/m. Because of their ability to support extreme accelerating gradients, the plasma medium has recently been proposed for future cavity-like accelerating structures. This contribution highlights the tremendous evolution of plasma accelerators driven by either laser or particle beams that allow the production of high quality particle beams with a degree of tunability and a set of parameters that make them very pertinent for many applications. | No matter the size of the hydro plant, if it has a long waterway and will operate in peaking mode, the project designer needs to address the issue of hydraulic transients-known as water hammer-early in the design. This article describes the application of transient analysis to the design of a 20-MW hydro plant in California. In this case, a Howell Bunger valve was used as a pressure regulating valve to control transient pressures and speed rise. | kor_Hang | 4,366 |
Improvement of Energy Efficiency for Combined Heat and Power System via Kuhn-Tucker Algorithm | This paper presents a novel design procedure for optimizing power distribution strategy in combined heat and power system. The optimal control problem was formulated as a nonlinear optimization problem subject to set of constraints. The resulting problem was solved using the Kuhn-Tucker method. Computer simulation results demonstrated that the proposed method provided better efficient in terms of reducing total costs compared to the existing methods. In addition, the proposed optimal load distribution strategy can be easily implemented in real-time thanks to the simplicity of the closed-form solutions. | A Chandra LETGS X-ray observation of α Centauri with an exposure time of 81.5 ks is presented with the two components (K1V and G2V) spectrally resolved for the first time. We use the emission lines from the individual spectra to determine plasma temperatures and find similar temperatures as for the Sun with higher temperatures for the K1V star than for the G2V star. Global fitting techniques are used in order to construct an emission measure distribution for each star and we find emission measure distributions consistent with what is found from the line ratios. A two-temperature model is used in order to derive abundances normalized to iron and relative to solar photosheric values. For both stars we find a FIP effect with a slight but not significant tendency of a stronger FIP effect for the K1V component. | eng_Latn | 4,367 |
Generation of Field Aligned Current During Substorm | A mechanism for the generation of field aligned currents during magnetospheric substorms is presented. The energy which is injected to the geomagnetic tail is converted into plasma flow energy in solar and anti-solar directions. When the flow meets the inner magnetosphere, a viscous interaction occurs. This interaction creates time-increasing vorticities which produce field aligned currents upward in the pre-midnight sector and downward in the post-midnight sector. | To overcome the nonlinear harmonic distortion,which is introduced by the inconsistencies between the frequency response of the loudspeaker units in digital loudspeaker system,three mismatch-shaping dynamic element matching algorithms are designed and implemented based on the 3 bit modulation coding,in reference to previous studies.The ability of harmonic suppression of these algorithms is tested in anechoic room and the performance of these algorithms is evaluated based on the experiment results. | eng_Latn | 4,368 |
Radial variations of large‐scale magnetohydrodynamic fluctuations in the solar wind | Two time periods are studied for which a relatively complete set of magnetic field and plasma measurements are available at both 1 AU (from IMP 8 and ISEE 3) and near 4 to 5 AU (from Voyager 1). One of these periods is characterized by the predominance of corotating streams, whereas many transient flows were observed in the second period. The evolution of these two flow systems with heliocentric distance is studied by using power spectral techniques. The power spectra for the system of transient flows are consistent with the hypothesis of turbulent evolution, including an inverse cascade of magnetic helicity to large scales. The power spectra for the system of corotating flows cannot be described so simply. | This paper presents the methodology and the physical models implemented in our computational code to predict the flow field over a Mars Sample Return Orbiter entering a Mars-like atmosphere. Because no validation against flight data or experiments can be done at present, the results obtained here are compared to other computed results for verification purpose. The predicted flow fields show that the chemical species CO and CO2, that are highly radiative species, are present in a large amount and at high temperature in the shock layer and in the wake of the flow past the orbiter. | eng_Latn | 4,369 |
Ball Lightning as a Self-Organized Complexity | The ball lightning phenomenon is explained in the frame of a self-organization scenario suggested by experiments performed on the spontaneously generated complex spherical space charge configuration in plasma. Originated in a hot plasma, suddenly created in a point where a lightning flash strikes the Earth surface, the ball lightning appearance proves the ability of nature to generate, by self-organization, complex structures able to ensure their own existence by exchange of matter and energy with the surroundings. Their subsequent evolution depends on the environment where they are born. Under contemporary Earth conditions the lifetime of such complexities is relatively short. A similar self-organization mechanism, produced by simple sparks in the earl Earth’s atmosphere (chemically reactive plasma) is suggested to explain the genesis of complexities able to evolve into prebiotic structures. | Abstract Perturbed correction to the heteroclinic orbit of a rf-driven Josephson system is derived from a direct perturbation technique. Theoretical analysis reveals that boundedness conditions of the orbit contain Melnikov criterion for the onset of chaos. Current–voltage characteristic associated with the bounded chaotic orbit is obtained, which implies current steps and shows qualitative agreement between the analytical results and experimental data. The results supply a more detailed analytical criterion for chaos in the system. | eng_Latn | 4,370 |
Bifurcation of nonlinear elliptic system from the first eigenvalue, Electron | We study the following bifurcation problem in a bounded domain in IR N : 8 : pu = juj jvj v + f(x; u; v; ) in qv = juj jvj u + g(x; u; v; ) in (u; v) 2 W 1;p 0 () W 1;q 0 () : We prove that the principal eigenvalue 1 of the following eigen- value problem 8 | It is shown that a finite-amplitude ion-acoustic wave in a uniform magneto- plasma can enhance two-dimensional plasma vortices. The latter results from a modulational instability. The growth rates are obtained analytically. | eng_Latn | 4,371 |
Phased high frequency current for energy collection in solar arrays | Abstract The new method for collecting energy from large area solar arrays in space is suggested. The solar array is made as thin film covering the rotating disk of a large radius. Electric power generated in the disk due to solar radiation absorption is converted into HF (High Frequency) current, but not into direct current as usually. The law of current distribution in the film is deduced. According to this law, the electromagnetic wave generated by HF current is focused in the center of the disk, just in the place, where the plasma engine could be located. The possibility of applying this wave directly to heat up working medium in the plasma engine is analyzed. | In this paper we use the SSWICH-SW software to calculate the (nonlinear) plasma potential near the ASDEX Upgrade 3-strap antenna for various operating parameters, and compare it with the (linear) parallel electric field strength and the (linear) RF potential. It is believed that the plasma potential is the cause of ion sputtering and additional heat loads on the antenna, and that the parallel electric field strength (as calculated by linear codes without sheath boundary conditions) is a good proxy for the plasma potential, and our results confirm the latter. | eng_Latn | 4,372 |
Magnetic field generation by pointwise zero-helicity three-dimensional steady flow of incompressible electrically conducting fluid | We introduce six families of three-dimensional space-periodic steady solenoidal flows, whose kinetic helicity density is zero at any point. Four families are analytically defined. Flows in four families have zero helicity spectrum. Sample flows from five families are used to demonstrate numerically that neither zero kinetic helicity density nor zero helicity spectrum prohibit generation of large-scale magnetic field by the two most prominent dynamo mechanisms: the magnetic α-effect and negative eddy diffusivity. Our computations also attest that such flows often generate small-scale field for sufficiently small magnetic molecular diffusivity. These findings indicate that kinetic helicity and helicity spectrum are not the quantities controlling the dynamo properties of a flow regardless of whether scale separation is present or not. | The first two parts of this series have developed the analysis of solid rotor machines for both flat and cylindrical models of infinite length. 1,2 The objective of this part is to present a representation of a finite length, flat model so that a correction for end effects may be incorporated in the operational impedance expressions. The correction presented gives a first-order approximation for this effect. The field analysis considering finite length is also of value in calculating air gap and rotor body spatial distributions of field quantities. | eng_Latn | 4,373 |
Experimental Studies of Seed-Free Pure-Inert-Gas Working MHD Power Generation | We describe the first MHD power generation experiment with seed-free high temperature inert gas (argon) plasma in a linear shaped Faraday type generator. The working gas with a total pressure and total temperature of 0.15 MPa and 9000 K, and a thermal input to the generator of 0.18 MW was produced using a single-pulsed shock tunnel. A magnetic flux density of 4.0 T was applied by a superconducting magnet. The almost nofluctuating electric output power has been obtained and the maximum power output is 19.7 kW, which corresponds to an enthalpy extraction ratio of 11.0% and a power density of about 240 MW/m 3 (at the 4th electrode region). These values are comparable to those in the conventional seeded plasma MHD generator. The higher performance can be expected under optimizations of generator shape and working conditions. | The survival of energy plants during the construction of the Three-Gorges Reservoir Project was investigated based on the specific geography and climate characteristics in this area.Some protective measures for energy plants were put forward in order to support government decision-making for development of biomass energy. | kor_Hang | 4,374 |
Large diameter melting by sparks | Abstract The causes of serious metallic melting due to discharges in the insulating gas of the Daresbury Tandem are examined. It is concluded that the damage is produced when the return stroke of the discharge experiences an impedance mismatch on re-entering the original single spark channel. The damage is at the site of the first spark which triggers the discharge but occurs at a later time. | Abstract An exact, three-dimensional, analytical description of the current distribution in the nozzle of an MHD channel, under imposed open conditions, is obtained. Strong vorticity of the current flow and high current concentration in the small regions toward the one side of the sidewalls and near the exit of the channel are found. | eng_Latn | 4,375 |
Magnetic Pressure as a Scalar Representation of Field Effects in Magnetic Suspensions | Magnetic microsphere suspensions undergo complex motion when exposed to finite sources of the magnetic field, such as small permanent magnets. The computational complexity is compounded by a difficulty in choosing a suitable choice of visualization tools because this often requires using the magnetic force vector field in three dimensions. Here we present a potentially simpler approach by using the magnetic pressure. It is a scalar quantity, pm = B2/2μ0, and its usefulness has been already demonstrated in applications to magnetohydrodynamics and ferrohydrodynamics (where B is the applied field and μ0 = 4π×10−7T.m/A). The equilibrium distribution of the magnetic bead plug in aqueous suspension is calculated as an isosurface of the magnitude of the magnetic pressure pm = const, in the field of two permanent magnet blocks calculated from closed formulas. The geometry was adapted from a publication on the magnetic bead suspensions in microsystems and the predicted bead plug distribution is shown to agree rema... | The topic of this volume, Particle Acceleration in Cosmic Plasmas, is the first in a series of three broad topics, each intended for a volume in Space Science Reviews and the Space Science Series of ISSI, that cover aspects of astrophysical plasma phenomena on all scales, from the Earth’s magnetosphere to the scale of clusters of galaxies. The other two topics cover “The Microphysics of Cosmic Plasmas” and “Structure Formation and Dynamics in Cosmic Plasmas”. The motivation for the series can be found in the conclusions of a discussion Forum held in the International Space Science Institute, Bern, Switzerland, in March 2009. The topic of the Forum was the question “Is there a future for magnetospheric research?”, originally formulated at a meeting of COSPAR’s Scientific Advisory Committee in March 2008. The discovery, exploration and detailed understanding of the Earth’s magnetosphere have been key scientific goals and the focus of significant activities in scientific space research in | eng_Latn | 4,376 |
Turbulence and anomalous tokamak transport control by Geodesic Acoustic Mode | The elementary process of turbulence control by Geodesic Acoustic Modes (GAMs) leading to modulation of its level at the GAM frequency is for the first time supported by experimental observations at the FT-2 tokamak. The modulation effect is confirmed by the global total-distribution-function gyrokinetic modelling of the tokamak discharge, predicting strong modulation of the electron thermal diffusivity induced by GAMs, which propagates inward and possesses the GAM temporal and spatial structure. | The steel structure of Hefei Xinqiao Airport Terminal is long-spanned and complicated,and some beams are truss beams and their sections are inverted triangle,so the simulation analysis of the construction process is necessary to ensure the smooth construction of the project.In this paper,by using the ETABS software,the simulations are carried out of the internal force of an assembling truss block in the truss frame during the construction.It is concluded that the overturn of assembling truss block on the ground can reduce the force of bars in construction.This construction method was accepted by the construction company to guide the structural construction. | eng_Latn | 4,377 |
Experimentally obtained values of electric field of an atmospheric pressure plasma jet impinging on a dielectric surface | We report on experimentally obtained values of the electric field magnitude on a dielectric surface induced by an impinging atmospheric pressure plasma jet. The plasma plume was striking the dielectric surface at an angle of 45°, at 5 mm from the surface measured at the axis of the jet. The results were obtained using Pockels technique on a BSO (Bi12SiO20) crystal. A coaxial configuration of the plasma jet was used, operating in a stable mode with one bullet per voltage period, at 30 kHz and amplitude of 2 kV. The electric field was shown to be a function of the gas flow (He, at 300, 500 and 700 SCCM) and the manner in which the discharge spreads over the dielectric surface. The maximum value of 11.6 × 105 V m−1 was obtained at the negative half-period of the discharge current measured at the grounded electrode, at the flow of 300 SCCM. The largest electric field averaged over the area of the spreading of the discharge (3.6 × 105 V m−1) was found in the same conditions. | In this paper, we consider the second order wave equation discretized in space by summation-by-parts-simultaneous approximation term (SBP-SAT) technique. Special emphasis is placed on the accuracy analysis of the treatment of the Dirichlet boundary condition and of the grid interface condition. The result shows that a boundary or grid interface closure with truncation error $\mathcal{O}(h^p)$ converges of order $p + 2$ if the penalty parameters are chosen carefully. We show that stability does not automatically yield a gain of two orders in convergence rate. The accuracy analysis is verified by numerical experiments. | eng_Latn | 4,378 |
[Introduction to partial seizures]. | A short introduction on the history, nature, type, classification and incidence of the partial seizures is done. The most suitable diagnostic studies and the used pharmacological and surgical methods of treatment for these type of seizures and which give a better quality of life. | We propose a simple scheme to start a parton-shower evolution description from a given jet configuration in ${e}^{+}{e}^{\ensuremath{-}}$ annihilation events. This allows a convenient combination of the full angular information content of matrix elements with the detailed sub-jet structure of parton showers, and should give a realistic overall description of event properties. Explicit studies with this hybrid approach are presented for the four-jet case, as a simple testing ground of the ideas. | eng_Latn | 4,379 |
Interactions of a plasma and an incoming ow at Mach 3 | Abstract A mechanical spike is a device used to mechanically act on the bow shock ahead of an airplane in supersonic flight. This action results in improved flight conditions. We will investigate here the eects of the axial generation of a two-hundred-micrometer width cylindrical plasma ahead a quasi-realistic nose profile of centimeter width. The device is named plasma spike by analogy to the above-cited mechanical device. This plasma spike is a source of both momentum and energy for the neighboring fluid. | Three phase asynchronous motor speed regulating theory is introduced in details in order to get motor speed regulating mechanical property.Based on matlab M language,it can accomplish speed regulating mechanical property of frequency regulation and slip regulating.M language program is easy and simulation figure is direct-viewing which can benefit speed regulation application of three pahse asynchronous machine. | eng_Latn | 4,380 |
Features of electron density and temperature in the 500–3500 km region of the plasmasphere—(1) Dawn and dusk sectors | Dawn-dusk features of the plasmasphere are examined for intervals in February and September 1969, using electrostatic probe data ofN e andT e from the ISIS-I satellite. Clear plasmatrough formation is seen in the vicinity of 70° geomagnetic latitude in both dawn and dusk sectors in the 1500–3500 km region, but the plasmatrough is absent in the altitude range 500–1500 km. The plasmatrough minimum near 70°φ exhibits no asymmetry between dawn and dusk sectors in its latitudinal position. TheT e peak associated with the plasmatrough is more pronounced in the dawn sector. DawnN e is less than duskN e, but dawnT e exceeds duskT e. The influence of processes in the magnetosphere in causing these features is examined. | A simplified treatment is proposed to study quantitatively the lattice dynamics of CsK, CsRb, and RbK alloy systems. The volume effect on the lattice dynamics of the pure constituent is considered, and the phonon dispersion relations of the local and band modes are obtained forthe Rb0.71K0.29, Rb0.3K0.7, Cs0.7K0.3, Cs0.7Rb0.3, and Cs0.3Rb0.7 systems. Then, the x-dependence of the local and band mode frequencies is calculated for the Rb1−xKx, Cs1−xKx and Cs1−xRbx systems. | eng_Latn | 4,381 |
Energy and angular distributions in dissociative photodetachment of O−4 | An anisotropic product angular distribution has been observed in the dissociative photodetachment of O−4 at 523 nm. Energy and angular distributions of coincident O2 products from the process O−4+hν→O2+O2+e− were measured using translational energy spectroscopy in a fast ion beam. The angular distribution peaks perpendicular to the electric vector of the laser beam. | In this paper, we extend our previous template analysis of a self-exciting Faraday disc dynamo with a linear series motor to the case of a nonlinear series motor. This introduces two additional nonlinear symmetry-breaking terms into the governing dynamo equations. We investigate the consequences for the identification of a possible template on which the unstable periodic orbits (UPOs) lie. By computing Gauss linking numbers between pairs of UPOs, we show that their values are not incompatible with those for a template for the Lorenz attractor for its classic parameter values. | eng_Latn | 4,382 |
Fan instability and limitation of the runaway-electron current | The effect of the fan instability of the runaway-electron tail on the dynamics of the acceleration of these electrons by the electric field is analyzed. A system of equations describing the conversion of the electron energy from longitudinal to transverse and also describing the anomalous electron thermal conductivity is derived and solved. These effects result from the fan instability. The anomalous electrical conductivity of a plasma is calculated from the runaway-electron current. | In this paper we study a degenerate evolution system ::: $\mathbf H_t +\nabla \times [|\nabla \times \mathbf H|^{p-2}\nabla \times \mathbf H]=\mathbf F$ in a bounded domain as well as its limit as $p\to \infty$ subject ::: to appropriate initial and boundary conditions. This system governs the evolution ::: of the magnetic field $\mathbf H$ in a conductive medium under the influence of a system ::: force $\mathbf F$. The system is an approximation of Bean's critical-state model for type-II superconductors. The existence, uniqueness and regularity of solutions to the ::: system are established. Moreover, it is shown that the limit of $\mathbf H(x, t)$ as $p\to \infty$ ::: is a solution to the Bean model. | eng_Latn | 4,383 |
Kinetic simulation of the Kelvin‐Helmholtz instability at the Venus ionopause | Two dimensional hybrid simulations with particle ions and fluid electrons are used to calculate the kinetic evolution of the Kelvin-Helmholtz instability at a boundary similar to the ionopause at the planet Venus. The magnetic field has been chosen to be essentially transverse to the plasma flow velocity, which is the most unstable case for the Kelvin-Helmholtz instability. Effects analogous to those found in MHD simulations are recovered, including a mode cascade to longer wavelengths. In addition, isolated structures on the order of the ion gyroradium are formed which can cross the boundary in either direction. These structures may be related to flux ropes commonly observed near the ionopause of Venus. The time evolution of these structures may represent transport across the boundary layers and the smearing of the shear layer may give rise to internal structure in the boundary. Similar processes occur in magnetized layers skin to the Earth's magnetopause. | With the help of maple,new explicit solitrary wave solutions of KdV-Burgers equation was obtained by bifunction method and Wu-eliminition method,thus the bifunction method was further complemented. | eng_Latn | 4,384 |
The magnetic field homogeneity of coils by means of the space harmonics suppression of the current density distribution | Abstract. Electromagnetic coils are ubiquitously used in the modern world in motors, antennas, etc. In many applications (magnetic field coil calibration and nuclear magnetic resonance spectroscopy and imaging) there is a strong need for a homogeneous magnetic field. In this paper, we propose a simple modelling based on serial Fourier decomposition allowing the determination of the electrical conductor distribution to make the magnetic field homogeneous. The method is valid both for plane and axisymmetric geometries. The method allows the retrieval of the classical configurations of saddle coil for the plane geometry and Helmholtz coil for the axisymmetric one. The method is generalized for any number of electrical conductors and brings the perspective of new homogeneous magnetic resonance imaging (MRI) coil configuration. | To apply continuation of potential field in spatial domain,Fredholm integral equation of the first kind has to be solved numerically.Because the coefficient matrix that comes from discretizing integral equation is not sparse and has very large scale,it requires large computer memory to save the matrix,and operation on it consumes very long time.The continuation method in spatial domain is not developed in practice.In this paper,based on the analysis of structure of coefficient matrix,we find an important fact that the coefficient matrix is a symmetric,block Toeplitz type matrix.A mathematical proof is given in the paper.By using fast algorithm that already exists to solve block Toeplitz system,we realize spatial domain upward continuation and downward continuation.Model data and aeromagnetic data test shows the feasibility and correctness of spatial continuation of potential field. | eng_Latn | 4,385 |
Motion of a two-temperature plasma in the channel of a disc-type magnetohydrodynamic generator | A study was made of the fully developed homogeneous flow of a two-temperature partially ionized plasma in the channel of a disc-type Hall generator. Experiments with a disc-type generator are described in [1, 2]. In a simplified statement, the problem is analogous to that considered in [3]. The present article takes the chemical reactions of ionization and recombination into account. The energy equation for an electron gas is brought down to a differential form which permits clarification of the question of the applicability of the Kerrebrock [4] formula for the difference in the temperatures of the electrons and the heavy particles. | Abstract The convergence properties of Machenhauer’s nonlinar normal-mode initialization scheme are explored. Only adiabatic initialization is considered. Several models are used, including an f-plane model. a numerical weather prediction model, and simple linear models with analytic solutions. The last are used to estimate a radius of convergence for Machenhauer's scheme. It is fist demonstrated with the f-plane model that Machenhaur's scheme may be approximated by one that is linear in gravity-mode coefficients. The components which diverge when the scheme is applied are shown to be linear combinations of gravity modes which interact due to advection. Those combinations which diverge fall into two categories those whom phase speed more than doubles as a result of advection, and those whose direction of propagation changes due to advection. These results agree with those of the simpler model of Ballish. Consideration of Ballish's model suggests that the inclusion of under-relaxation in Machenhauer's sche... | eng_Latn | 4,386 |
Generation of an electron cyclotron resonance plasma using coaxial‐type open‐ended dielectric cavity with permanent magnets | A high density, uniform, and compact electron cyclotron resonance (ECR) plasma source which utilizes surface‐wave radiation and a near‐surface magnetic field is described. The microwaves propagated through a coaxial waveguide are introduced circularly into the circumferential side of a dielectric Al2O3 disk, which is placed at the open end of a coaxial‐type cavity. The ECR magnetic field is similar to three concentric planar magnetron configurations and is directed away from the dielectric surface by permanent magnets set in the center conductor of the coaxial‐type cavity. A surface wave is launched from the dielectric disk surface and generates an ECR plasma. The plasma density and electron temperature are 2.0×1011 cm−3 and 2.2 eV, respectively, at an Ar gas pressure of 10 mTorr and a microwave power of 700 W. The ion saturation current density (Isat) and its uniformity are 8.2 mA/cm2 and ±5.5% within a radius of 10 cm. | Abstract In this paper, we delve into the dynamics of a barothropic relaxing medium under pressure perturbations originating from blast wave explosions in the milieu. Analyzing the problem within the viewpoint of the Lyakhov formalism of geodynamic systems, we derive a complex-valued nonlinear evolution equation which models the wave propagation of the pressure perturbations within the barothropic medium. As a result, we find that the previous system can be circularly polarized and hence support traveling rotating pressure excitations which profiles strongly depend upon their angular momenta. In the wake of these results, we address some physical implications of the findings alongside their potential applications. | eng_Latn | 4,387 |
SADE: The starspot and dynamo explorer | Abstract We propose a mission called SADE, the Starspot And Dynamo Explorer, to study dynamo activity in nearby late-type stars. The onboard instruments will be a Ca-K telescope for magnetically dominated chromospheric emission, and an X-ray grazing incidence telescope to study coronal emission. We design the mission for a life-time of 15 years or longer to capture a full activity cycle for most solar-type stars. We aim to firmly establish the spectrum of the relation between chromospheric and corona' emission in late-type stars, and capture one or more stars going into or coming out of a Maunder type minimum. Operation costs will be kept to a minimum by automating mission operations to a maximum, and have the science operations be carried out by students at Montana State University. | This paper presents the recent development of the pulsed power technology based on inductive energy storage (including Superconducting Magnetic Energy Storage, SMES) and its opening switch. It also introduces several circuit topologies with power electronics/superconducting opening switch. | eng_Latn | 4,388 |
With the symbol Wb what is the unit of magnetic flux? | schoolphysics ::Welcome:: HOME > AGE 16 - 19 > ELECTRICITY AND MAGNETISM > ELECTROMAGNETISM > FLUX AND FLUX DENSITY Flux and flux density To understand the meaning of magnetic flux (Φ) and magnetic flux density (B) think first about an ordinary bar magnet. Around the magnet there is a magnetic field and this gives a �flow of magnetic energy� around the magnet. It is this flow of energy that we call magnetic flux (Φ). We think of magnetic flux as flowing from the north pole of a magnet round to its south pole as shown by the arrows on the lines in the diagram. Looking at the diagram you should see that there is as much flux flowing �from the north pole� as there is �flowing into the south pole�. Magnetic flux is given the symbol Φ and is measured in units called Webers (Wb). However the amount of magnetic flux flowing through a given area will change from one point to another around the magnet and you can understand this by thinking about a loop of wire placed in the field at two different points (A and B). You can see that in position B there are a smaller number of magnetic field lines passing through the loop than there is when it is in position A. We call the amount of flux passing through a unit area at right angles to the magnetic field lines the flux density (B) at that point. Flux density is measured in Tesla (T) where 1 T = 1 Wbm-2 So: Flux (Φ) = Flux density (B) x area through which flux passes (A) Φ = BA If we now use more than one loop of wire, in others words a coil of N turns as shown in position C the flux flowing through the N turns is simply N times that flowing through the single loop. The quantity NΦ is called the the flux linkage for the coil at that point. Therefore: | NWS JetStream MAX - Beaufort Wind Force Scale JetStream Max: Beaufort Wind Force Scale Sir Francis Beaufort Rear-Admiral, Sir Francis Beaufort, was born in Ireland in 1774. He entered the Royal Navy at the age of 13 and was a midshipman aboard the Aquilon. By 1800 he had risen to the rank of Commander. In the summer of 1805 Beaufort was appointed to the command of the Woolwich, a 44 gun man-of-war. In 1806 he wrote in his log book a wind force scale. The scale was simple and very similar to one that Alexander Dalrymple had written in a book in 1789. A year later he added some criteria to the 0-12 scale that indicated how much of a ship's sails would be employed by a British man-of-war under each condition. It was not related to the speed of the wind. Over the following years he continued to use his scale in his logs. It was finally adopted in December 1838 by the British Admiralty for use in all Royal Navy logbooks. However, as ship design and the introduction of steam power became widespread even that scale had to be modified. In 1912 the International Commission for Weather Telegraphy sought some agreement on velocity equivalents for the Beaufort scale. A uniform set of equivalents was accepted in 1926 and revised slightly in 1946, extending the scale to 17 values (the added five values further refining the hurricane-force winds). By 1955, wind velocities in knots replaced Beaufort numbers on weather maps. Today's Beaufort Scale including the observed land conditions... Beaufort | eng_Latn | 4,389 |
How does flatulence travel through the room when opening a window? When the smell in my room seems to be full of flatulence(it wasn't me), what happens with the gases when I open a window? Detail: It is winter and the air outside is cold whereas the air in the room is warm. When I close the window the smell of flatulence comes back nearly right away. What does the process of diffusion look like here? And would the smell be dispersed faster if I sprayed another odor into the room? | When I open a window to air out the room, how does the smell disperse? Let's say I'm in a room with some kind of noxious stink, possibly of flatulent nature. The quickest way to right the world that comes to mind is to open a window. When I open a window, how do the stank particles leave the room? | Was Kylo Ren's Blaster Bolt Freezing Really Force Telekinesis? In this questions answer its stated that Kylo Ren freezes the blaster bolt in midair with telekinesis: Because he is extremely skilled in Force telekinesis, Kylo Ren is able to freeze not just objects but even blaster bolts in midair. But as a commenter already pointed out, this seems nonsense (even in star wars force physics). The blaster bolt is, as far as I know, a cloud of plasma. If it is stopped by telekinesis, why should it continue its old path with its old speed after it is released? Wasn't it more a completely new force ablility like "time freeze"? While I admit in a case of time freeze the bolt should not have flickered all the time. Also the plasma should have expanded and vanished or simply cooled down releasing its energy to the surrounding air. So when it was force telekinesis Kylo must have done the following: Stop every atom in the plasma cloud Keep the cloud compressed and in form and shape. Isolate it to prevent the heat flow or keep it on temperature (is this still telekinesis?) Not just releasing it but accelerate it again exactly on its old path and speed. This would be indeed a greate never seen mastery of telekinesis. And very ineffective. And if he wanted to be cool, wouldn't it be even cooler to change the path after the "release" so that it hits one of his enemies? So what was going on there? Pure telekinesis or something else? Did the writers intend this? Or did they just not thinking it to the end? | eng_Latn | 4,390 |
Why do higher level players move between each attack? I always see players move between every attack, even if they are attacking a stationary target (for instance a tower) and there is no theat close that would make their current position worth changing? I think this practice is called "kiting". So why are they doing this, is there any advantage to modifying your position between every attack? | Attack moving or Attack Canceling I watch streams sometimes and i see the high elo Ranged AD move between each shot. Do they gain anything with this? And if so whats a good way to practice it. | Was Kylo Ren's Blaster Bolt Freezing Really Force Telekinesis? In this questions answer its stated that Kylo Ren freezes the blaster bolt in midair with telekinesis: Because he is extremely skilled in Force telekinesis, Kylo Ren is able to freeze not just objects but even blaster bolts in midair. But as a commenter already pointed out, this seems nonsense (even in star wars force physics). The blaster bolt is, as far as I know, a cloud of plasma. If it is stopped by telekinesis, why should it continue its old path with its old speed after it is released? Wasn't it more a completely new force ablility like "time freeze"? While I admit in a case of time freeze the bolt should not have flickered all the time. Also the plasma should have expanded and vanished or simply cooled down releasing its energy to the surrounding air. So when it was force telekinesis Kylo must have done the following: Stop every atom in the plasma cloud Keep the cloud compressed and in form and shape. Isolate it to prevent the heat flow or keep it on temperature (is this still telekinesis?) Not just releasing it but accelerate it again exactly on its old path and speed. This would be indeed a greate never seen mastery of telekinesis. And very ineffective. And if he wanted to be cool, wouldn't it be even cooler to change the path after the "release" so that it hits one of his enemies? So what was going on there? Pure telekinesis or something else? Did the writers intend this? Or did they just not thinking it to the end? | eng_Latn | 4,391 |
Airfoil theory --- Why does air travel faster above? I do not understand, why the air above the airfoil travels faster than the air below it? The air above has to travel faster than the air below so that both streams meet simultaneously at the trailing edge --- why do the streams have to meet simultaneously ? PS : I understand the Bernoulli principle and how the lift is created by the pressure difference and all that. | Why does the air flow faster over the top of an airfoil? I understand the common explanation of lift, which describes the airflow over the top of the wing as moving faster than the air below the wing. However, I don't quite understand why the air moves faster. I've read some explanations citing a circulation effect among others, but haven't found a good, clear explanation for the exact cause. Can someone help me out? | Was Kylo Ren's Blaster Bolt Freezing Really Force Telekinesis? In this questions answer its stated that Kylo Ren freezes the blaster bolt in midair with telekinesis: Because he is extremely skilled in Force telekinesis, Kylo Ren is able to freeze not just objects but even blaster bolts in midair. But as a commenter already pointed out, this seems nonsense (even in star wars force physics). The blaster bolt is, as far as I know, a cloud of plasma. If it is stopped by telekinesis, why should it continue its old path with its old speed after it is released? Wasn't it more a completely new force ablility like "time freeze"? While I admit in a case of time freeze the bolt should not have flickered all the time. Also the plasma should have expanded and vanished or simply cooled down releasing its energy to the surrounding air. So when it was force telekinesis Kylo must have done the following: Stop every atom in the plasma cloud Keep the cloud compressed and in form and shape. Isolate it to prevent the heat flow or keep it on temperature (is this still telekinesis?) Not just releasing it but accelerate it again exactly on its old path and speed. This would be indeed a greate never seen mastery of telekinesis. And very ineffective. And if he wanted to be cool, wouldn't it be even cooler to change the path after the "release" so that it hits one of his enemies? So what was going on there? Pure telekinesis or something else? Did the writers intend this? Or did they just not thinking it to the end? | eng_Latn | 4,392 |
The original Pons/Fleischmann experiment was deeply flawed, and it seems the same errors are reproduced in followup experiments these past 30 or so years. The Pons/Fleischmann apparatus was not properly purged of He before the experiment. An independent examination of their electrodes, ‘Measuring helium in electrolyzed palladium’ precisely quantified the presence of He in the P/F electrodes, but one lab noted that this looked like the palladium contained He from a manufacturing process. Precious metals are typically processed with an induction furnace and an inert atmosphere of helium or argon. “Induction furnaces are widely used throughout metallurgy not just because of their efficient melting abilities, but also because of their usefulness in forging new alloys. Because induction is a no-contact process that doesn’t utilize combustion, induction furnaces can work in inert atmospheres and vacuums – which is necessary when creating alloys that oxidize if heated in the presence of air. As an additional benefit, the magnetic forces in an induction furnace can be directed to stir the molten metal, which is very useful for creating fully homogenized alloys.” So, there really is no question of a nuclear fusion reaction without any validated reaction products. That the same errors are repeated over and over again by cold fusion proponents in search of a positive result suggests something pathological. | Cold fusion is being mentioned a lot lately because of some new setup that apparently works. This is an unverified claim. See for example: ( of that last link in the Wayback Machine, given frequent from that page.) While we should give the scientific community time to evaluate the set up and eventually replicate the results, there is undoubtedly some skepticism that cold fusion would work at all, because the claim is quite extraordinary. In the past, after Fleischmann and Pons announced their cold fusion results, in perfectly good faith, they were proven wrong by subsequent experiments. What are the experimental realities that make Fleischmann and Pons style cold fusions experiments easy to get wrong? Would the same risks apply to this new set up? | I am sitting inside a closed room with a cement ceiling just above my head. The pressure of the atmosphere is exerted on the ceiling from above(outside). But solid cement not being a fluid does not transport that pressure into my room. But i still feel the atm pressure which has no way to be transported into the room.I do not boil to death or anything. How does this happen? | eng_Latn | 4,393 |
Is a GFCI receptacle device a circuit breaker? I have been told that a GFCI receptacle is a "circuit breaker" in the sense that it will trip under overload. Everything I know, have been told, and have read from experts to manufacturers says this is not the case. So the question stands: Is a GFCI receptacle device a circuit breaker? | Does a GFCI receptacle provide overcurrent protection? Does a GFCI receptacle provide over-current protection? (note that I'm not referring to GFCI circuit breakers as may be found in a service panel, nor to specialty devices such as an inline plug-in GFCI that may offer over-current protection) I've checked some GFCI (note, this link opens a PDF) but haven't found any that mention overcurrent protection, or provide trip curves as would be expected in a circuit breaker datasheet. So, does a GFCI receptacle provide any inherent over-current protection or must it always be used with a circuit breaker for over-current protection? This question was prompted by where the answer suggests using a GFCI outlet as a circuit breaker. This seems like very big misconception of the protection offered by a GFCI, and is potentially dangerous if it leads someone to think that GFCI outlets are the same as circuit breakers. | What exactly happens to the signals hitting a common mode choke? I'm trying to better understand the principles behind the common mode choke. I made a few drawings to clarify. Differential Mode Signals Differential currents (driven by differential voltages) create equal but opposite magnetic fields B in the inductor core: These magnetic fields cancel each other out, so the net flux in the core is zero. As such, these differential currents don't "feel" any impedance. Common Mode Signals In contrast, common mode currents generate equal and additive magnetic fields in the core. That's why they "feel" a high impedance, and cannot get through (or getting through means they are highly attenuated). But what exactly happens? I have several theories, which I will describe below. Common Mode Signals - Theory 1 My first thought would be that the common mode signal hits the choke and creates a magnetic flux inside. By doing this, lots of energy is lost (hysteresis and perhaps other effects) as heat. Only a small part gets through: What kind of common mode choke would behave in this particular way? "Burning up" the voltage spike seems a very desirable effect to me. Common Mode Signals - Theory 2 Perhaps the voltage spike doesn't really get the chance to build up much magnetic flux in the core, or maybe the core is simply not "lossy" enough. The voltage spike bounces off the core and turns back. Only small part gets through: Although the system on the right side of the choke is protected, the system on the left has to deal with reflected signals. Nasty things like standing waves might appear. My questions I've got a few questions for you: Do you think theory 1 or theory 2 is most plausible? Do you think certain types of common mode chokes tend to behave as described in theory 1, others like in theory 2? Perhaps both of my theories are just plain wrong. If so, what actually does happen? Please enlighten me. | eng_Latn | 4,394 |
Will these rods increase chances of a lightning stroke on the metallic structure or they will help to save it. Why we need to place lightining rods on a mettalic structure when the whole building itself is a conductor. Placement of lightning rods will increase the height of the metallic building and will it not more susceptible to lightning strokes now than without lightning rods? A detailed answer is requested please | you need to place lightining rods as you call them, i call them " ground" rods is to ground out the building per say, that way if struck by lightining, the path of electric is to be grounded out | In physics and chemistry, a plasma is typically an ionized gas, and is usually considered to be a distinct phase of matter in contrast to solids, liquids and gases. "Ionized" means that at least one electron has been dissociated from a proportion of the atoms or molecules. The free electric charges make the plasma electrically conductive so that it responds strongly to electromagnetic fields.\nExcept near the electrodes, where there are sheaths containing very few electrons, the ionized gas contains ions and electrons in about equal numbers so that the resultant space charge is very small. We shall use the name plasma to describe this region containing balanced charges of ions and electrons.\nMore specifically, a plasma is an electrically conductive collection of charged particles that responds collectively to electromagnetic forces. Plasma typically takes the form of neutral gas-like clouds or charged ion beams, but may also include dust and grains (called dusty plasmas) . They are typically formed by heating and ionizing a gas, stripping electrons away from atoms, thereby enabling the positive and negative charges to move freely.\nPlasma properties are strongly dependent on the bulk (or average) parameters. Some of the most important plasma parameters are the degree of ionization, the plasma temperature, the density and the magnetic field in the plasma region. \nPlasma parameters can take on values varying by many orders of magnitude, but the properties of plasmas with apparently disparatFor plasma to exist, ionization is necessary. The degree of ionization of a plasma is the proportion of atoms which have lost (or gained) electrons, and is controlled mostly by the temperature. Even a partially ionized gas in which as little as 1% of the particles are ionized can have the characteristics of a plasma (i.e. respond to magnetic fields and be highly electrically conductive).\n\nPlasma temperature is commonly measured in Kelvin or electron volts, and is (roughly speaking) a measure of the thermal kinetic energy per particle. In most cases the electrons are close enough to thermal equilibrium that their temperature is relatively well-defined, even when there is a significant deviation from a Maxwellian energy distribution function, for example due to UV radiation, energetic particles, or strong electric fields. Because of the large difference in mass, the electrons come to thermodynamic equilibrium among themselves much faster than they come into equilibrium with the ions or neutral atoms. For this reason the ion temperature may be very different from (usually lower than) the electron temperature. This is especially common in weakly ionized technological plasmas, where the ions are often near the ambient temperature.\n\nTemperature controls the degree of plasma ionization. In particular, plasma ionization is determined by the electron temperature relative to the ionization energy (and more weakly by the density) in accordance with the Saha equation. A plasma is sometimes referred to as being hot if it is nearly fully ionized, or cold if only a small fraction (for example 1%) of the gas molecules are ionized (but other definitions of the terms hot plasma and cold plasma are common). Even in a "cold" plasma the electron temperature is still typically several thousand degrees. Plasmas utilized in plasma technology ("technological plasmas") are usually cold in this sense.\nNext to the temperature, which is of fundamental importance for the very existence of a plasma, the most important property is the density. The word "plasma density" by itself usually refers to the electron density, that is, the number of free electrons per unit volume. The ion density is related to this by the average charge state of the ions through . (See quasineutrality below.) The third important quantity is the density of neutrals n0. In a hot plasma this is small, but may still determine important physics. The degree o | eng_Latn | 4,395 |
Last week, Iran successfully tested a multi-warhead, intercontinental ballistic missile capable of reaching Israel and US bases in the region. This week, they tested an equally menacing torpedo. | why not as long as others like \nIsreal have it. | A Tokamak is a machine that creates a doughnut-shaped magnetic field; a plasma (basically a bunch of ionized atoms, each with a positive or negative charge) gets trapped in the magnetic field, which we call being “confined” by the field. By manipulating the magnetic field and the quantity of plasma, extremely high pressures and temperatures can be attained. For this reason, the Tokamak design is used for fusion research—the hope is that the ions and electrons in the plasma can be squeezed so close together that they will overcome electrical repulsion and fuse together, releasing energy in the process. (Two positively-charged ions, for example, experience strong electrical forces that push them apart when they get close together, but if they get close enough, nuclear forces can overcome the repulsion, and the ions can fuse to form a larger one.)\n\nFusion happens all the time in extreme environments—the interior of the Sun, for example, where it provides the enrgy for our star to shine—but humans have never managed to achieve controlled fusion. Instead, we’ve only managed the uncontrolled variety—in the form of hydrogen bombs.\n\n\nRyan Wyatt\nRose Center for Earth & Space\nNew York, New York | eng_Latn | 4,396 |
How does cold plasma differ from regular plasma? | How is cold plasma different from regular plasma? | Nuclear Fusion: Can magnetically contained plasmas tunnel through the confinement? | eng_Latn | 4,397 |
what is fluxus group | Fluxus is an international avant-garde group or collective that was founded and flourished in the1960s but still continues today. | Flux-Cored Arc Welding was introduced in the 1950s. It is a process that is very closely related to Metal Inert Gas Welding. Both processes use similar equipment and continuous wire feeds, and both MIGW and FCAW use the same type of power supply. | eng_Latn | 4,398 |
I made a plasma vortex at my home, but why doesn't it produce a zapping sound like at time when we see sparks and does the air nearby it ionizes? | I made a plasma vortex at my home, but why doesn't it produce a zapping sound like at time when we see sparks and does the air nearby it, ionizes? | Saying that zero point energy is infinite and that there are infinite potential virtual particles in vacuum is real or a mathematical thing? | eng_Latn | 4,399 |
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