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High dynamic range imaging and application to laser-plasma diagnostics in inertial confinement fusion (ICF) experiment | High dynamic range and large format technique of micro-chanunel plate (MCP), gated framing camera is developed to diagnose high-power laser-plasma X-ray emission spectra. The single frame format is 13 mm×36 mm, and exposure time is adjustable from 0.5 ns to 5 ns. Its spectral response in 1.0—10 keV is more flat than that of X-ray charge-coupled device (CCD), and there exists no energetic enhancement effect. Performance evaluation has been conducted on high power laser devices, and the results show that the system has a high signal-to-noise ratio and the dynamic range is greater than 3 × 10 3 . The system has been applied successfully to inertial confinement fusion (ICF) physics experiment. | A prototype IIR digital bandpass filter is derived from an analogous bandpass filter by using bilinear transformation. The formulas relating the digital bandpass filter's coefficients with its center frequency and bandwidth are obtained. Using N sections of such digital bandpass filter, a cascade IIR digital bandpass filter is constructed. Based on the specifications and the formulas given, the parameter N and bandwidth of prototype IIR digital bandpass filter can be obtained, and the unknown cascade IIR digital bandpass filter can be finally determined. The filter has few coefficients and a simple structure and it is easy to be designed. It is especially suitable for its implementations when using DSP. | eng_Latn | 8,000 |
The Output Wave Control of Digital Generator Based on LM3S615 | The LM3S615,which contains pulse-width modulation(PWM) producer and is very cheap,has great application potential in digital waveform generator to control the output signal.The influence of dead-zone effect in the circuit is mainly discussed.It is found that increasing the width of the narrow high level together with combining several carrier cycles can effectively eliminate the output signal distortion and give perfect sinusoidal wave. | Abstract This paper describes the design and principle behind the demonstrated novel lamellar grating out-of-plane gyroscope design. The sensing mechanism is based on out-of-plane motion of movable light-reflecting beams changing the phase relationship between the light reflected off the two sets of beams. This phase relationship is manifested as an intensity change in the zeroth-order diffracted light. The device consists of two in-plane 180° out-of-phase vibrating masses with a set of overlapping light-reflecting beams behaving essentially as a lamellar grating. The commercial SOI-MUMPS process was used to fabricate a prototype. The gyroscope demonstrated a sensitivity of 17.8 μV/(°/s) and linearity error of less than 0.6%. Design issues were addressed and show promise to be overcome. Post-fabrication tuning and better optics design can improve the performance greatly with respect to the current prototype setup. | eng_Latn | 8,001 |
Effects of dot height uniformity on the performance of 1.3 /spl mu/m InAs quantum dot lasers | We have systematically investigated the growth parameters of InAs quantum dots (QDs) so as to preserve the uniformity of dot height for 1.3 /spl mu/m QD laser diodes. Devices that are prepared using the optimized growth conditions exhibit threshold current as low as 50 mA, and internal quantum efficiency as high as 63% under continuous-wave operation. | The fractal characteristics of attenuation are evaluated, and an attempt is made to establish an alternative theoretical model for ultrasonic scattering at grain boundaries. The theoretical development starts with attenuation scaled by wavelength and an inverse power law expression for the grain size distribution function. The wavelength dependence of the attenuation is found to be also an inverse power law with the same exponent as the grain size distribution function. Theoretical justifications for such a size distribution are given, as well as the representation of a 3-D self-similar size distribution in a 2-D image. > | eng_Latn | 8,002 |
Optical Damage Resistance Of Lithium Niobate Waveguides | The optical damage resistance of diffused lithium niobate wave-guides is discussed. Long-term laser power handling performance is assessed by recording the spatial intensity changes occurring as a function of time in a waveguide's far field. Out-diffused waveguides are found to offer significantly greater long-term resistance to optical power losses caused by optical damage than do waveguides formed by either ion exchange or titanium in-diffusion. Any waveguide's resistance to optical damage is lowered by inadvertent exposure to chemical reducing conditions that can prevail during device fabrication processes. Waveguides exposed to the severe chemical reducing conditions are found to exhibit dramatically nonlinear behavior when exposed to high laser powers and short laser wavelengths. | The improved method for calculating the Lyot filter parameters has been developed. The two-plate and three-plate Lyot ::: filters transmission spectra for the low threshold lasers tuned in the 1100-1300 nm spectral region are computed. | kor_Hang | 8,003 |
A fibre optic dosimeter for prostate cancer therapy | Comparative measurements of the performance of a fibre optic dosimeter designed for prostate cancer therapy, a MOSFET and diamond detector are presented. The fibre optic dosimeter compares well with the alternatives. | Cationic fluorophore homodimer probes 1 and 2 bearing 7-aminocoumarin and naphthalimide dyes, respectively, connected via diethylenetriamine (DETA) spacer, have been developed to demonstrate the validity of our modular probe design on the basis of the triamine-based spacer. | eng_Latn | 8,004 |
Ultrafast laser mode-locked using nonlinear polarization evolution in polarization maintaining fibers | We demonstrate an ytterbium laser oscillator mode-locked by means of Nonlinear Polarization Evolution realized in Polarization Maintaining (PM) fibers. The all-PM-fiber laser generates 150 fs pulses at 20.54 MHz repetition rate. | The photosensitized oxidation of single bilayer vesicles of egg-yolk lecithin by singlet oxygen is investigated. The isotopic enhanced lifetime of singlet oxygen in heavy water, and the inhibitory effect of azide ions, are both used to examine the O2(1Δg) diffusion characteristics. The rate of photo-oxidation of unsaturated fatty acid is shown to be strongly dependent on the precise location of the sensitizer in the bilayer. Rate constants for the interaction of singlet oxygen with the lipid, with the acceptor 9,10-dimethylanthracene and with azide are determined to be 7.5 × 105, 3.2 × 108 and 1.0 × 108 dm3 mol–1 s–1, respectively. | eng_Latn | 8,005 |
Design and Application of Optical Voltage and Current Sensors for Relaying | Optical voltage and current sensors offer several benefits for use in high-voltage substations. Interface to relays and other secondary devices is one of the key issues when using optical sensors. Low energy analog interfaces provide an effective way for connecting optical sensors to relays. In this paper, several examples and applications of optical sensors connected to relays and recorders using low and high energy analog interfaces are discussed. In all cases, the performance of the entire system has been satisfactory. Lessons learned in these applications are also discussed | We report the formation of Ohmic contacts to high‐dose (∼1016 cm−2) Te‐implanted n‐type GaAs annealed with a Q‐switched Nd : YAG laser. The annealing results in a Te concentration greater than 10 times the equilibrium solubility and the formation of free Ga at the surface. Ohmic contacts of specific contact resistance rc≃2×10−5 Ω cm2 were obtained by first removing the surface Ga by an HCl etch and then backsputtering to remove 50 A of GaAs, thereby exposing a surface of high Te concentration. | eng_Latn | 8,006 |
Inter-modulation distortion reduction in multi-mode wireless communication terminal | First radio access technology (radio access technology; RAT) and a multi-mode wireless communication terminals communicating by using a 2 RAT, the first RAT and the second 2 RAT is to determine whether the active state, the first RAT and wherein the 2 RAT is based at the same time, the voice codec rate of the claim 2 RAT voice transmission on when in the active state to modify the maximum transmission power limit of the claim 1 RAT, wherein the first 2 RAT is the from the awake state It performs voice transmission. In an alternative embodiment, the threshold is modified on the basis of the transmission type of the transmission power state, or claim 1 of claim 2 RAT RAT. | Because of the nonuniformity and instability of atmosphere,it is very difficult to obtain real-timely and precisely a band of infrared atmospheric extinction coefficient with MODTRAN atmospheric transmission software and any other traditional methods.The nonlinear function relationship between the input and output of neural network can be obtained via the relation among the atmospheric optical properties at different wavelengths in the near-infrared band by generalized regression neural network.Then the atmospheric optical properties at other wavelengths can be further derived through real-time inversion of the data at certain wavelength measured by laser radar.The method was proved to be effective in obtainning real-timely the near-infrared atmospheric optical properties of a band in actual combat conditions. | eng_Latn | 8,007 |
Automated Tunable Diode Laser Monitoring Systems | Fully automated tunable diode laser systems have been developed for the long-term, precision monitoring of gases, liquids, and solids. Active laser feedback stabilization allows continuous, unattended monitoring of the chemical or physical characteristics of materials. Specific systems will be described for the measurement of nuclear reactor performance, nonregulated automotive emissions, and extruded plastic quality. Common elements in all these systems are computerized laser stabilization and control, ultra-stable sampling cells, and optimized detectors selected for long-term, maintenance free operation. | Recently large area avalanche photodiodes with high performance, narrow operation tolerances and high reliability became available. We report on some tests of their performance for the readout of fast scintillators. > | kor_Hang | 8,008 |
Percutaneous anaesthesia with a lignocaine-prilocaine cream (Emla) for eyelid skin surgery. | Epicutaneous application of the anaesthetic cream Emla (lignocaine and prilocaine), to induce percutaneous anaesthesia in 38 patients scheduled for eyelid skin surgery is presented. The cream was applied 60 to 90 minutes before operation. In 36 out of the 38 patients (94.8%) no supplementary analgesia was required. The pain during the procedure was rated either as no pain in 29 patients (76.3%), slight pain in five patients (13%), moderate pain in two patients (5.2%), and severe pain in two patients (5.2%). Percutaneous anaesthesia induced by Emla cream is a useful and painless alternative method for analgesia in eyelid skin surgery. | Direct electrical pumping of polymer lasers is considered to be a great challenge. Our recent experiments indicate the laser action in a nanostructured polyaniline diode. This has been identified as an electrically pumped random laser, in which a conducting polymer (nanostructured polyaniline) plays the role of an active medium. The device of a simple LED architecture is directly electrically powered at a low voltage of 5–15 V. Above the threshold voltage (4–8 V) and the electrical energy pumped (75–100 W), different laser modes are generated, including the emission of nearly monochromatic light. This is the first electrically pumped random laser, based on a nanostructured conductive polymer – polyaniline. These results are groundbreaking in the field of polymer lasers, which are directly electrically powered. The impact of the findings is not limited either to this particular device or to the specific material used. | eng_Latn | 8,009 |
Anchoring Strength Characteristics of Micro-Grating Structures Fabricated by Direct Laser Writing | Alignment characteristics of nematic liquid crystals on micro-scale grating structures fabricated by direct laser writing employing two photon excitation has been investigated upon changing periods and heights of the grating. Liquid crystal was infiltrated in the cell made of a substrate with gratings and another glass substrate with polyimide rubbed in the direction almost parallel to the grating vector of the structure in order to realize a twisted nematic configuration. Anchoring energies of the gratings were evaluated using the torque balance method, and were confirmed to be proportional to the height and inversely to the period of the grating. While the anchoring energy of the gratings turned out to be weaker compared to substrates treated by the conventional rubbing method, varying periods and heights of the grating allowed control of the anchoring energy. | Method and system for luminescence molecular imaging or tomographic attention region in the scattering medium are disclosed. The system includes a non-linear luminescent marker material disposed in the scattering medium. Thereby, the contrast and resolution of the imaging or tomographic imaging is improved. Nonlinear markers, for example, configured to up-convert the incident light of the illumination wavelength. The non-linear power dependency marker, allowing further improvement of imaging by using an image obtained using two or more excitation beams simultaneously. | eng_Latn | 8,010 |
Utilization of moderate cylindrical confinement for precision improvement of laser-induced breakdown spectroscopy signal. | Moderate cylindrical cavity was used to regularize the laser-induced plasma for signal strength enhancement and precision improvement in laser-induced breakdown spectroscopy (LIBS). A polytetrafluoroethylene (PTFE) plate of 1.5 mm thickness with diameter of 3 mm was fabricated. It was placed closely on a sample surface and a laser pulse was shot through the center of the hole to the sample. Using coal as samples, it was verified that the configuration both enhanced the spectral line intensity and reduced shot-to-shot fluctuation, showing its great potential in improving the precision of LIBS analysis. | In this paper we have analyzed the modal dispersion characteristics of two unconventional Bragg waveguides namely hypocycloidal and elliptical Bragg waveguide by the use of very simple matrix method. We are using matrix equation which replaces the boundary condition. We obtained the characteristic equation analytically. In both cases all the outputs are showing in the form of dispersion curves and we are also trying to compare their dispersion characteristics. It is seen that in case of hypocycloidal Bragg waveguide [1] the cut off frequency increases with the decrease of cladding layers .But in case of elliptical Bragg waveguide [2], when the cladding layer decreases from six layered to four layered the cutoff frequency increases and from four layer to two layer the cutoff frequency become decreases. | eng_Latn | 8,011 |
Femtosecond trapping efficiency enhanced for nano-sized silica spheres | We present a comparison of optical trapping of 50-nm-sized silica nanospheres, suspended in water medium, by ::: femtosecond laser pulses and by continuous wave laser beam. With bright field microscopic imaging, we demonstrated ::: that intensity of scattering light at the focal area under fs-pulse mode is much higher than that under cw mode. This result ::: offers a basic interpretation that trapping efficiency of nanometer-sized particles by the ultrashort laser pulses is higher ::: than that by the cw mode at the same laser power. We interpret this finding by means of impulsive peak power of the ::: femtosecond laser pulses. | Abstract A fluorescence microscopic technique was used to observe phase transitions in monolayers of DPPC. The sizes of the domain structures observed were found to be dependent on the rate of compression of the monolayer. The distribution of domain sizes for different rates of compression were unimodal, but the scatter in the sizes was greater during slow compressions. | eng_Latn | 8,012 |
Interferometric methods for the measurement of wavefront aberrations | The measurement of wavefront aberrations for optical imaging systems plays a major role in the field of modern optics. Measurements with a Fizeau type interferometer and a shearing type interferometer are described. The interferometric set-up for the shearing interferometer and the algorithms, in particular for the evaluation of the wavefront aberration, are described in more detail. Various methods for the measurement of wavefront aberrations are compared. | The use of far-IR injection lasers in pulsed molecular high-resolution spectroscopy is addressed. Far-IR radiation generation in a magnetoplasma spectral window is reviewed. The frequency tuning of long-wavelength diode lasers under combined temperature and magnetic field influence is examined. | eng_Latn | 8,013 |
Vertical Cavity Surface Emitting Lasers | Vertical-cavity surface-emitting lasers (“VCSELs”) and VCSEL arrays are disclosed. In one aspect, a surface-emitting laser includes a grating layer having a sub-wavelength grating to form a resonant cavity with a reflective layer for a wavelength of light to be emitted from a light-emitting layer and an aperture layer disposed within the resonant cavity. The VCSEL includes a charge carrier transport layer disposed between the grating layer and the light-emitting layer. The transport layer has a gap adjacent to the sub-wavelength grating and a spacer region between the gap and the light-emitting layer. The spacer region and gap are dimensioned to be substantially transparent to the wavelength. The aperture layer directs charge carriers to enter a region of the light-emitting layer adjacent to an aperture in the aperture layer and the aperture confines optical modes to be emitted from the light-emitting layer. | Background: ::: Microvascular proliferation is a major risk factor for plaque vulnerability in patients with carotid stenosis. There are several vascular endothelial markers such as CD31 and CD105, but it is unclear which marker is most sensitive for microvessels. This study sought to examine the correlations between CD31 and CD105 expression in microvessels on carotid plaques and clinical manifestations. | eng_Latn | 8,014 |
The effect of renal ligation on serum penicillin levels produced by penicillins G and K in rabbits. | Evidence is presented that in rabbits complete renal ligation results in prolongation of blood levels following the injection of either penicillin K or penicillin G. A theory is advanced that both excretion and an undetermined inactivation mechanism are involved in the failure of penicillin K to maintain adequate blood levels in rabbits. This inactivation mechanism is believed also to inactivate penicillin G but to a lesser extent than penicillin K. | We have calculated the electronic band structure and polarization dependent optical gain in a strain balanced SixGeySn1−x−y/GezSn1−z based transistor laser (TL) with GezSn1−z single quantum well (QW) in the base. Design consideration for QW is also addressed to ensure moderate carrier and optical confinement. A significant TE mode optical gain is obtained in mid infra red region for the transition of Г valley conduction band to heavy hole valence band. Optical gain in the QW plays an important role in determining the optical characteristics of Tin (Sn) incorporated group IV material based TL. | eng_Latn | 8,015 |
Quasi-phase-matched high harmonic generation using trains of uniformly-spaced ultrafast pulses | We investigate quasi-phase-matching of high harmonic generation over a range of harmonic orders using trains of up to 8 uniformly-spaced counter-propagating pulses, produced using an array of birefringent crystals. | We propose a numerical method for calculating bifurcations of periodic solutions observed in a model equation of Hodgkin–Huxley neurons coupled by excitatory synapses with a time delay. To illustrate the validity of the method, bifurcations in two-coupled Hodgkin–Huxley equations with variation of a coupling coefficient and time delay are studied. | eng_Latn | 8,016 |
An optical ladder filter II using optical fiber and directional coupler | The digital ladder filter has different cintinued fractional expansions due to the types of ladder filter and it can or can not be realized by given transfer function. In this paper, considering the Ⅱ typa of ladder digital filter, we design formulae and cindition of realibility for optical fibers and directional couplers. | Summary form only given. We report significant improvements in the performance of laser diodes based on semiconductor superlattices, arising from improved extrinsic materials properties and better laser design. Active layers are multiple quantum wells consisting of thin GaInSb-InAs superlattice quantum wells interleaved between GaInAsSb barrier layers. This design was chosen to remove the constraint of lattice match between the GaInSb-InAs superlattices and the substrate, allowing structures with superior intrinsic characteristics to be employed. | eng_Latn | 8,017 |
Photoelectron satellite spectrum in the region of the 3s Cooper minimum of argon. | The 3s,3p satellite spectrum of argon has been studied with use of synchrotron radiation in the 40--70-eV energy range. In the region of the 3s Cooper minimum (42.5 eV\ifmmode\pm\else\textpm\fi{}0.2), the integral intensity of the satellites is ten times larger than the 3s partial cross section. The angular asymmetry parameters have been measured as a function of the photoelectron energy for the 3s ${}^{2}$S,3p ${}^{2}$P final states as well as for the satellites. For the lowest photon energies it appears that the \ensuremath{\beta} parameter values of the most intense satellites are strongly dependent on the total angular momentum of the final ionic state. | Since their discovery microresonator-based frequency combs have drawn a lot of interest due to their compact form factor and potential for integration. We report on the recent progress regarding dissipative Kerr solitons generated from photonic chip-based microresonators and their use in different fields of application. | eng_Latn | 8,018 |
A novel single-input multiple-output encoder/decoder and its application to optical packet switching | We propose a single-input multiple-output en/decoder, which can simultaneously and flexibly generate and separate a group of independent optical codes in the different optical paths with a specific permutation and combination of code patterns. We demonstrate the en/decoder for all-optical label processing in an optical packet switching system. | We have performed high-throughput characterization of composition-spread La 1-x Ca x MnO 3 (LCMO) and Nd 1-x Sr x MnO 3 (NSMO) films, fabricated by the precursor technique, with a scanning SQUID microscope (SSM). In both films, SSM successfully observed spatial variation of magnetic field, corresponding to magnetic phase transitions with respect to chemical composition. The obtained magnetic phase diagrams basically reproduced those reported in bulk materials. However, several distinctive differences have also been noted. For instance, the region identified as a charge ordered insulator in LCMO revealed intense field, suggesting the occurrence of phase separation into ferromagnetic and non-magnetic states. These results confirm that SSM possesses sufficient analytical performance for high-throughput characterization of combinatorial magnetic libraries in composition spread form. | eng_Latn | 8,019 |
Hybrid-integrated coherent receiver using silica-based PLC technology | We present a hybrid-integrated coherent receiver module using flip-chip technology for coupling a silica-based 90o-hybird planar lightwave circuit (PLC) chip to a spot-size converter integrated waveguide photodiode (SSC-WG-PD) array chip for a balanced photodiode (BPD) and interconnecting with a dual-channel transimpedance amplifier (TIA). | Abstract Under adequate growth conditions the mixed layer compounds (PbS) 1+ x (NbS 2 ) n and (BiS) 1+ x (NbS 2 ) n are shown to crystallize from the vapour phase partly as hollow cylindrical scrolls, which can be either chiral or achiral. Also conically would scrolls are formed. The observations of the growth nuclei suggests a formation and growth mechanism based on the spontaneous curling up of thin triangular flakes as a consequence of the lattice parameter difference between the constituent lamellae of the mixed layer compounds. Morphological observations are supported by electron diffraction patterns, which are interpreted in terms of the reciprocal space of conically wound fibres, first presented here and developed in detail in Ref. [20] [S. Amelinckx et al., Acta Cryst., submitted]. The scroll nature of rolled microstructures allows for the formation of long and complicated periodic sequences of orientation variants. | eng_Latn | 8,020 |
Continuous-Wave Tunable and Superfluorescent Operation of a Monomode Ytterbium-Doped Fiber Laser | Efficient laser action has been observed in a monomode Yb3+-doped fibre at 974nm (three level transition) and at 1036nm, with output powers of 9.3mW and 15.7mW respectively and slope efficiencies of 67% and 77% respectively. Q-switched operation yielded pulses of 25ns at 974nm and 100ns at 1041nm. Tunable cw operation from 1010nm to 1162nm has been demonstrated. In addition, efficient superfluorescent emission has been observed at 974nm and around 1040nm with output powers of 10mW and 31mW respectively and slope efficiencies of 45%. | Abstract The evolution of the state vector of a system composed of a cascade three-level atom and a single-mode field with arbitrary detuning and initial condition has been obtained. The quantum fluctuations of the field are presented. The contribution of single- and two-photon transitions to the squeezing of the field is discussed. The dependence of the squeezing on initial intensities of the field and detuning are given. | eng_Latn | 8,021 |
Phase sequence construction for near optimum SLM | High Peak-to-Average Power Ratio (PAPR) is a major drawback of multicarrier transmission systems such as OFDM. Among various techniques proposed for PAPR reduction, SeLective Mapping (SLM) is a stochastic approach with the potential to achieve maximum PAPR reduction via phase optimization. In this paper, a measurable criterion for determining suitable phase sequences for near optimum SLM is derived, following which a large number candidates in the form of MPSK sequences are formulated to achieve near optimum SLM performance. A low cost search algorithm for the transmitter is also investigated. | We present what is to our knowledge the most complete 1-D numerical analysis of the evolution and the propagation ::: dynamics of an ultrashort laser pulse in a Ti:Sapphire laser oscillator. This study confirms the dispersion ::: managed model of mode-locking, and emphasizes the role of the Kerr nonlinearity in generating mode-locked ::: spectra with a smooth and well-behaved spectral phase. A very good agreement with experimental measurements ::: of pulse energy, spectrum, and temporal width of extracavity compressed pulses is found. | eng_Latn | 8,022 |
Optoelectronic device for bidirectionally transporting information through optical fibers and method of manufacturing such a device | An optoelectronic device for bidirectionally transporting information through glass fibers between logically distributed users and a central station by means of transceivers of said central station. In particular, a set of several glass fibers (32) is connected in an array having a predetermined pitch to a multiple-operation coupling element (36) that is provided with lenses and that guides the downstream and upstream radiations from the glass fibers through a multiple-operation wavelength divider (40) which effects a spatial separation between the downstream and upstream radiations such that said downstream and upstream radiations are imaged on radiation sources (44) and photodetectors (46), respectively, said radiation sources being spatially separated from said photodetectors. | Abstract A new type of bifluorophoric molecule consisting of two heterocycle-linked coumarin fluorophors is studied. A high laser efficiency, a broad tunability range and good photostability for two synthesized biscoumarins are observed. One of the proposed biscoumarins covers the green spectral region where the efficiency of known laser dyes is relatively low. | eng_Latn | 8,023 |
Er3+:Sr5(VO4)3F: A Potential Passive Q-Switch for Er-Glass Lasers | Er3+ in multi-site Sr5(VO4)3F is evaluated spectroscopically for its potential as an intracavity saturable absorber passive Q-switch for Er-glass lasers. | We consider the cross area of the PP_ and PSV_wave window as the best window for joint PP_ and PSV_wave acquisition in VTI media. Within the effective window, the PP_ and PSV_wave's raypathes and phase angles at all reflection points are calculated, and the reflection (or transmission) coefficients' ratios of PSV- to PP_wave solved from Zoeppritz equations are defined as the controlling factor G. Then we use G values as the main controlling parameters of joint PP_ and PSV_wave acquisition design in VTI media, determine the best receiving window of detectors by analyzing G values, and derive the method of optimizing the receiving window for acquisition of multi_component converted seismic data in VTI media. | eng_Latn | 8,024 |
Large Orbital Magnetic Moment in Feo, Fes and Febr2 | Magnetic moment of the Fe2+ ion in FeO, FeS and FeBr2 has been calculated within the quantum atomistic solid-state theory to substantially exceed a value of 4 muB in the magnetically-ordered state at 0 K. In all compounds the large orbital moment, of 0.7 - 1.1 muB, has been revealed. Our calculations show that for the meaningful analysis of electronic and magnetic properties of FeO, FeS and FeBr2 the intra-atomic spin-orbit coupling is essentially important and that the orbital moment is largely unquenched in 3d- ion containing compounds. | In this paper, we investigate the performance of the Sub-carrier Multiplexed-Free Space Optics (SCM-FSO) for transmitting Code Division Multiple Access (CDMA) signals in terms of Carrier-to-Noise-plus-Interference Ratio (CNIR) and Bit Error Rate (BER), under Gamma-Gamma turbulent FSO channel. We propose an analytical model for optimization of the SCM-FSO link and a closed-form BER expression taking into account the nonlinear effects of the SCM optical link as well as the strong atmospheric turbulence of the FSO channel. We emphasize how the choice of optimal optical modulation index (OMI) can increase the received CNIR and also its dependency on the attenuation of the FSO channel. We then discuss the effect of atmospheric turbulence on the received BER. It is shown that, for a high quality CDMA signals reception over the SCM-FSO system, the link has to be engineered to perform optimally in terms of received optical power, number of carriers and OMI. | eng_Latn | 8,025 |
Nonlinear-Mirror Modelocked 323-fs Thin-Disk Oscillator | We present the first nonlinear-mirror modelocked thin-disk laser, delivering 21 W at 323 fs pulse duration. This opens a new chapter for the nonlinear-mirror technique which, until now, only modelocked few-ps bulk oscillators. | -We describe a simple method to generate wavelength-tunable pulses by using a semiconductor optical amplifier (SOA) as an intensity modulator and a gain medium. Wavelength tunable pulses at a repetition rate of 4.8 GHz have been generated. | eng_Latn | 8,026 |
Hot‐carrier light emission from silicon metal‐oxide‐semiconductor devices | Light emitted from energetic electrons and holes near the drain region of Si field‐effect transistor devices is measured spectrally resolved in the important energy range about the band gap. Using a sensitive Ge detector we examine the spectral range from 0.75 to 1.55 eV in order to identify and study the recombination of impact ionization generated electron‐hole pairs. Two distinct recombination lines are observed superposed on a continuum background. | The computer controlled Laserthermia system by the method of using double ::: channel endoscope with the contact frosted probe and a thermocouple was reported ::: previously.25 In this paper, the single channel method with the new single ::: laser delivery system was studied experimentally. Especially hyperthermal effect ::: by the newly developed Hybrid Laserthermia feedback probe(Hybrid probe) was discussed ::: comparatively with the effects by the interstitial contact probe. The Hybrid ::: probe could be possible to treat clinically more accurate Laserthermia in ::: the near future. | eng_Latn | 8,027 |
Measurement of Atmospheric Turbulence by 2-μm Doppler Lidar | Abstract Two methods for the estimation of the turbulence energy dissipation rate (TEDR) from data measured by a 2-μm coherent Doppler lidar are described in this paper. Based on data measured at the Tarbes-Lourdes-Pyrenees International Airport in summer 2003, height profiles of TEDR have been retrieved. The results of TEDR estimation both from the Doppler spectrum width and from the velocity structure function are compared. Moreover, the experiment has been treated by numerical simulation and the theoretical results have been used for verification of the described methods. | -We describe a simple method to generate wavelength-tunable pulses by using a semiconductor optical amplifier (SOA) as an intensity modulator and a gain medium. Wavelength tunable pulses at a repetition rate of 4.8 GHz have been generated. | eng_Latn | 8,028 |
Enhancement of the accuracy of estimating a pulse’s instant of arrival | Estimation of a signal’s instant of arrival is considered. It is assumed that the arriving signal has a known shape and is distorted by a Gaussian white noise. An example is presented to show that application of the output matched-filter signal to this problem is inefficient. For solving such problems, a sufficient statistic is proposed. The components of this statistic are obtained from an orthogonal decomposition of observed data in the case when the Fisher information on the signal delay is retained. It is shown how to use this approach for synthesizing an estimation algorithm that ensures an accuracy better than the accuracy guaranteed by maximum-likelihood estimates. | In this paper, simulations are conducted to investigate high speed uni-traveling-carrier photodiodes (UTC-PDs). The Gaussian doping profile, which can introduce potential gradient and electric field, is presented to be used in the absorption layer. Compared to constant doping and step-graded doping, bandwidth of UTC-PD with Gaussian doping is improved substantially. | eng_Latn | 8,029 |
Pulser injection with subsequent removal-implementation and applications | The technique of pulser injection with subsequent removal has been developed to provide truly automated gamma-ray spectrometry. The operator is freed from the requirements of pulser-peak positioning and rate adjustment common with standard pulser implementations. Use of the concurrently gathered pulser data to correct for spectral gain and zero shifts, monitor spectrometer performance in real time, compensate for resolution degradation with input rate, and correct for random summation and deadtime effects results in accurate analyses with a minimum of operator intervention. Digital logic in a special pulser control and separation module is used to modify (or not modify) ADC (analog/digital converter) addresses based on pulser-tagging logic signals. The authors describe the implementation, performance testing, and applications of this technique. > | In this paper, simulations are conducted to investigate high speed uni-traveling-carrier photodiodes (UTC-PDs). The Gaussian doping profile, which can introduce potential gradient and electric field, is presented to be used in the absorption layer. Compared to constant doping and step-graded doping, bandwidth of UTC-PD with Gaussian doping is improved substantially. | eng_Latn | 8,030 |
Intracellular GaN Microrod Laser | We report fabrication of GaN microrods and their intracellular lasing characteristics for individual cell tracking and labeling application. © 2019 The Author(s) | Abstract Very small metal and semiconductor wires are of great interest for experiments on electron and phonon transport in one-dimensional structures. Methods of fabricating wires with sub 0.1μm linewidth are discussed and the procedures used to make a metallic loop of linewidth 20 × 20nm and 50 by 100nm GaAs wires described in detail. The ultimate resolution of electron beam lithography using polymeric resist is reviewed. | kor_Hang | 8,031 |
Highly efficient generation of entangled photon pair by spontaneous parametric downconversion in defective photonic crystals | We study the process of spontaneous parametric downconversion in a one-dimensional defective quadratic nonlinear photonic crystal. It is shown that the strong confinements of both the pump and signal waves around the defective layer result in a giant enhancement of the entangled photon-pair generation. An enhancement factor as high as 3.4×106 is obtained in our defective structure based on the dual-localized modes. Furthermore, the linewidth of the downconverted fields is only 0.1 nm. Such a photonic crystal structure can be applied as a highly efficient source of entangled photon pairs for highly integrated all-optical circuits. | Image segmentation is an important problem of digital image processing and also a common difficult problem. In this paper, a new image thresholding method based on parzen-window estimation and Renyi entropy is proposed. The method used Parzen-window technology to estimate the spatial probability distribution of image gray level values, then combined with the Renyi entropy to construct a new criterion function, and at last searched the optimal global threshold in the scope of gray level to maximum the criterion function. This new method has some advantages, such as high accuracy to image segmentation, fine stability comparing with the traditional Renyi entropy method. | eng_Latn | 8,032 |
Helically twisted photonic crystal fibres | Recent theoretical and experimental work on helically twisted photonic crystal fibres (PCFs) is reviewed. Helical Bloch theory is introduced, including a new formalism based on the tight-binding ap... | A new technique to determine the nonlinearity of high-speed photodiodes is presented. Utilizing a linearized phase-modulated link architecture, we directly measure the photodiode intermodulation distortion. Our results agree with those obtained via a phase-locked laser technique. | eng_Latn | 8,033 |
Research on Acceleration Performance Indices for Serial Mechanism | Previous performance indices are generalized and analyzed briefly first of all, then on the basis of first-order and second-order kinematical influence coefficient matrices, including acceleration performance index, linear acceleration performance index, angular acceleration performance index and acceleration global condition performance index and so on, a set of acceleration performance indices for serial robot are proposed. Different from previous indices, these indices include not only the first-order kinematics influence coefficient matrix G, but also the second order kinematics influence coefficient matrix H. Finally, with these performance indices, PUMA 260 serial industrial robot's dynamic performance are analyzed. The results show that these new indices are feasible in mechanism's dynamic performance analysis. So these indices can be used to guide the dynamics design of serial mechanism. | -We describe a simple method to generate wavelength-tunable pulses by using a semiconductor optical amplifier (SOA) as an intensity modulator and a gain medium. Wavelength tunable pulses at a repetition rate of 4.8 GHz have been generated. | eng_Latn | 8,034 |
A parallelizable recursive least squares algorithm for adaptive filtering, with very good tracking properties | In this paper, a new Recursive Least Squares (RLS) algorithm for Finite Window Adaptive Filtering is presented, that has a number of interesting and useful properties. First, owing to the specific structure of the updating formulas and due to the fact that the past information is, for the first time, directly dropped by means of a proper inversion Lemma stated and proved in this paper, the proposed algorithm is immediately parallelizable. Second, it is more robust than many RLS Kalman-type schemes, in the sense that it is more resistant to the finite precision error effects. At the same time, the proposed algorithm has very good tracking capabilities. Finally, it can constitute the basis for the development of O(m) computational complexity algorithms that have very interesting properties, too, i.e. they are robust, parallelizable and they have particularly good tracking properties. | We proposed a simple method to realize optical Fourier transform during the nonlinear wave shaping processes. In this method, an integrated optical superlattice is designed to realize multiple optical functions, which plays important roles in both the nonlinear harmonic generation process and the optical Fourier Transform process. We demonstrated our method by the nonlinear generation of Airy beams as an example. It is a universal method for beam shaping and is of practical importance for designing compact nonlinear optical devices. | eng_Latn | 8,035 |
ring of aminothiol level in blood using a near-infrared dye assisted deep tissue fl uorescence and photoacoustic bimodal imaging † | The development of molecular probes for the detection and imaging of biological thiols is a major step forward diagnosing various types of diseases. Previously reported thiol imaging strategies were mainly based on a single mode of imaging with a limited application in vivo. In this work, we introduced an unsymmetrical near-infrared (NIR) squaraine dye (USq) as an exogenous contrast agent for photoacoustic and fluorescence bimodal imaging of thiol variations in live animals. USq exhibits a narrow absorption band at 680 nm that generates a photoacoustic signal and a strong NIR emission at 700 nm (ΦF = 0.27), which is applicable for deep tissue optical imaging. Both photoacoustic and fluorescence signals could selectively disappear in the presence of different thiols. Through in vitro and in vivo imaging studies, unique imaging capability of USq was demonstrated, and the effect of food uptake on the increased level of aminothiols in blood was confirmed. | The transmission performance of single-sideband alternate mark inversion return-to-zero (SSB-AMI-RZ) formats, with duty-cycles of 15%, 30% and 50%, in long-haul 40 Gbit/s/channel ultra dense WDM systems with 50 GHz of channel spacing is assessed through systematic numerical simulation. After optimizing the bandwidths and detuning of optical multiplexer and demultiplexer, the dispersion maps are optimized for each duty-cycle. From these, the tolerances to the in-line residual dispersion (IRD) and total residual dispersion (TRD), and the nonlinear thresholds (NLT) are assessed. It is shown that the different SSB-AMI-RZ formats have high tolerance to linear crosstalk, due to a - 20 dB bandwidth much smaller than the channel spacing, and similar tolerance to IRD. Numerical results indicate that the format with duty-cycle of 15% outperform the others because of its better tolerance to TRD and higher NLT. | eng_Latn | 8,036 |
Q-switching of a thulium-doped fibre laser using a holmium-doped fibre saturable absorber | We have proposed and demonstrated a new passively Q-switched thulium-doped fibre laser configuration. A distinctive feature of this configuration is the use of a heavily holmium-doped fibre for Q-switching. Lasing was obtained at 1.96 μm, with a pulse energy of 3 μJ and pulse duration of 600 ns. The highest pulse repetition rate was 80 kHz. | The variation-perturbation method using finite basis sets is applied to the hydrogen molecular ion H+ 2. Sets of ‘pseudostates’ consisting of N pairs of effective oscillator strengths and transition energies are determined and tabulations with N = 6, for both parallel and perpendicular electric dipole transitions, are presented over a range of internuclear distances. Various oscillator strength sums, including those involving the logarithms of the transition energies, and Rayleigh-Schrodinger perturbation theoretic expressions are evaluated. In particular, the isotropic and anisotropic components of the dipole-dipole dispersion energy between H+ 2 and each of a number of atoms, H2, and N2 are determined using published pseudostates. | eng_Latn | 8,037 |
On the $\sigma_L/\sigma_T$ Ratio in Polarized Vector Meson Photoproduction | We study the spin-dependent cross-sections of vector meson photoproduction for longitudinally and transversely polarized photons within a QCD- model. The dependence of the $\sigma_T/\sigma_L$ ratio on the photon virtuality and on the meson wave function is analysed. | Digital signal processors have made it possible to control scanned probe microscopes using straightforward software emulations of analog circuits. Using a system consisting of a commercially available digital signal processor board interfaced to analog I/O, we have developed algorithms for self‐optimizing feedback, raster generation (with hysteresis correction, sample tilt compensation, and scan rotation), lock‐in detection, and automatic tip‐sample approach. We also discuss an instruction parser that takes advantage of the digital architecture to allow automatic operation for extended periods. | eng_Latn | 8,038 |
Pulse shaping for laser controlled fusion | Stimulated Brillouin scattering from bismuth mirrors was used to shape laser pulses to a desived length and contrast. A Q-switched photodissociation iodine laser provided the input radiation. (AIP) | In recent years, tube hydroforming has been applied in automobile and airplane industries, to decrease weight. In general, the determination of internal pressure path is a key factor in improving the formability in tube hydroforming. One of the effective methods in improving the tube hydroforming is using the pulsating internal pressure path. In this research, hydroforming of bi-layered tubes under pulsating pressure in x-shaped die is simulated by means of three dimensional finite element method. Some numerical results were compared with experimental results and show good correlation. Influence of pulsating pressure on the thickness and stress distribution have been also studied. It was shown that pulsating pressure improves the formability in hydroforming of bi-layered tubes via continues and gradual removing returnable wrinkling which is caused by a low pressure in this process. In addition, effect of some key parameters such as friction and die corner filling have been investigated. | eng_Latn | 8,039 |
Phase-Controlled Photocurrents in Semiconductors | We show that one can optically control the photoresponse of semiconductor devices by the phase of the EM incident radiation. This can be achieved by interfering two phase-locked quantum pathways, both projecting the same initial bound state to the same energy level in the continuum. An experimental study on quantum well infrared photodectectors is presented. | Multilevel Conversion systems have certain advantages that can be applied in renewable energy systems. To verify that advantages we are developing a re-configurable 1 kW prototype. Among the experiments that we have considered, a sliding mode control law can force this converter to behave like an AC Current Source. We model our converter like a set of Tibuck converters operating sequentially. Some experimental results are given. | eng_Latn | 8,040 |
Numerical Results for the Hubbard Model: Implications for the High T c Pairing Mechanism | AbstractNumerical studies of the Hubbard model and its strong-coupling form, the t-J model, show evidence for antiferromagnetic, ::: $$d_{x^{\text{2}} - y^2 } $$ ::: -pairing and stripe correlations which remind one of phenomena seen in the layered cuprate materials. Here, we ask what these numerical results imply about various scenarios for the pairing mechanism. | The computer controlled Laserthermia system by the method of using double ::: channel endoscope with the contact frosted probe and a thermocouple was reported ::: previously.25 In this paper, the single channel method with the new single ::: laser delivery system was studied experimentally. Especially hyperthermal effect ::: by the newly developed Hybrid Laserthermia feedback probe(Hybrid probe) was discussed ::: comparatively with the effects by the interstitial contact probe. The Hybrid ::: probe could be possible to treat clinically more accurate Laserthermia in ::: the near future. | eng_Latn | 8,041 |
Direct intensity modulation of three-guide coupled rectangular ring laser having bidirectional lasing characteristics | We investigate the modulation properties of a three-guide coupled rectangular ring laser having bidirectional lasing ::: characteristics. Two different rectangular lasers having active section lengths of 250 and 350 μm and total cavity lengths ::: of 580 and 780 μm are fabricated. The rectangular laser cavity consists of four low loss total internal reflection mirrors ::: and an output coupler made out of three passive coupled waveguides. For both the clockwise and counterclockwise ::: circulating directions, the lasing threshold currents of around 38 mA are obtained at room temperature under continuous ::: wave operation. A 3-dB modulation bandwidth over 3 GHz is observed in both circulating directions for two different ::: lasers. | PURPOSE: An apparatus for an optical touch screen is provided to accurately detect the storage location of a pointing device. CONSTITUTION: A light source(10) generates a light, and plural beam splitters(20) reflects some lights generated from the light source. The progression of the light reflected from some of plural beam splitters crosses the progression of the light reflected from the other beam splitters. The light source is a laser diode or an LED(Light Emitting Diode) generating an infrared ray. The plural beam splitters include a first heat beam splitter group and a second heat beam splitter group. | eng_Latn | 8,042 |
Description of a wire bonder using a laser as a welding agent | This paper describes a heavy wire bonder that uses a laser fusing technique to join the wire with the contact pads of both the circuitry and the outside connector which is part of the package. It describes the fusing process and the reasons for the choice of the process. | We present recent test results and discuss design challenges on x-ray optical components for the wiggler sources at CHESS and for the proposed energy recovery linac (ERL) source at Cornell. For the existing wiggler sources, a new white-beam collimating mirror has been installed and tested at F-line and some preliminary test results are presented. For the proposed ERL, three types of x-ray optical components are identified and considered: (1) high-heat-load capable optics for high-power and high-power-density insertion-device sources, (2) brilliance preserving optics that can provide high transverse coherence, and (3) optics used to manipulate, preserve and produce short x-ray pulses. | eng_Latn | 8,043 |
Optimization of the conductively cooled packaging in QCW diode lasers | In order to improve the output power and the reliability of the diode lasers with the quasi-continuous-wave(QCW) average power of ×102 W,the doubled-side cooling is used in conductively cooled packaging.The results show that after the use of the doubled-side cooling,the maximum output power and the slope efficiency of the diode laser are improved from 91.6 W,1.09 W/A to 98.4 W,1.16 W/A,respectively,and the threshold current is decreased from 15.6 A to 15.1 A.The wall-plug efficiency is increased slightly,too.Under the current of 100 A,both the chip temperature and thermal resistance are also decreased.The packaging with the doubledside cooling can better dissipate the heat in the diode laser bars. | In this paper, we propose a novel type-II hybrid ARQ scheme using low density parity check (LDPC) codes. The proposed approach combines low hardware overhead with good decoding performance by using an efficient decoder operating at a much higher rate with a much smaller size parity check matrix. Our scheme makes parts of the previously received data gradually improved until successful decoding of the entire original codeword. We also present a novel efficient framework for constructing rate-compatible LDPC codes applied in our hybrid ARQ scheme. The progressive edge growth (PEG) construction method with zigzag pattern results in linear-time encoding. | eng_Latn | 8,044 |
All-optical switching in two cascaded nonlinear directional couplers. | We report on what is to our knowledge the first demonstration of all-optical switching in two integrated nonlinear directional couplers cascaded together in series. The directional couplers were fabricated from AlGaAs and operated at a wavelength of 1.53 microm, which corresponded to the half-band gap. The two devices were fabricated on the same chip, thereby eliminating coupling and reflection losses. We also report on the effects of pulse breakup. | In this paper, we consider a group of agents with state and input constraints. The objective of this paper is to make the agents reach a desired formation while avoiding constraint violations. This paper considers two types of constraints: coupled and decoupled constraints. We prepare so-called a safe region which contains all the pairs of initial states such that both types of constraints are satisfied. In order to meet the objective, we present a distributed receding horizon control algorithm consisting of two algorithms: decision making algorithm and reference management algorithm. We show that the present algorithm achieves constraint fulfillment under some reasonable conditions. | eng_Latn | 8,045 |
Photoconductive detection of millimeter waves using proton implanted GaAs | We show that ion-damaged GaAs may be used to detect millimeter electromagnetic waves in photoconductive sampling gates. The semi-insulating GaAs material which was implanted with a dose of 1014 cm−2 protons at an energy of 200 keV gave a signal to noise improvement of about 11.4 dB when compared with as-grown semi-insulating GaAs. The improvement is in spite of a reduced carrier mobility in the ion-implanted material and is due to the shorter carrier lifetime and formation of ohmic contacts with the ion-damaged semi-insulating GaAs. | We report fabrication of GaN microrods and their intracellular lasing characteristics for individual cell tracking and labeling application. © 2019 The Author(s) | eng_Latn | 8,046 |
Squeezed Light from a Self–Frequency-Doubling Laser | We present the analysis of a laser in which an intractivity χ(2)-nonlinear element couples the lasing mode to its second harmonic. The cavity is resonant for both modes. We investigate the potential for squeezing in this system by linearizing the quantum fluctuations around the steady states of the problem. In principle, more than 50% noise reduction below the vacuum level is possible in the second-harmonic field outside the cavity. The maximum squeezing, which is neither pure amplitude nor pure phase squeezing, occurs at a finite frequency-offset from the cavity resonance. | For a maneuvering target, the Doppler of scatterers take the form of LFM signals after movement compensation. Superresolution methods are based on the models of both the signal and the noise. In this paper, we extend the Relax algorithm to the case of LFM signals and apply it to monopulse three dimensional imaging. Simulation results shows that the images thus formed are superior to those formed by the traditional dechirping method. | eng_Latn | 8,047 |
Tunable SERS in Gold Nanorod Dimers through Strain Control on an Elastomeric Substrate | In this Letter we provide experimental verification of the interparticle distance dependence of the SERS enhancement factor in 1 μm gold gapped nanorods. Au dimers are fabricated from electrochemically grown heterogeneous Au−Ag−Au nanorods and deposited on a stretchable elastomer film which allows active and reversible tuning of the interparticle gap on the sub-5-nm level. Significantly, this technique allows the distance dependence to be tracked using a single dimer, thereby avoiding enhancement factor reproducibility issues arising from morphological differences in disparate nanoparticle pairs. | We present what is to our knowledge the most complete 1-D numerical analysis of the evolution and the propagation ::: dynamics of an ultrashort laser pulse in a Ti:Sapphire laser oscillator. This study confirms the dispersion ::: managed model of mode-locking, and emphasizes the role of the Kerr nonlinearity in generating mode-locked ::: spectra with a smooth and well-behaved spectral phase. A very good agreement with experimental measurements ::: of pulse energy, spectrum, and temporal width of extracavity compressed pulses is found. | eng_Latn | 8,048 |
Abstract 15513: EPRS Promotes Cardiac Fibrosis by Regulating Proline-Rich Pro-Fibrotic Protein Synthesis | Introduction: Increased synthesis of pro-fibrotic proteins is a common feature of cardiac fibrosis. However, critical factors and mechanisms for translational control of cardiac fibrosis remain unc... | We built a pulse compressor using a comb-like dispersion-profiled fiber (CDPF). The CDPF consists of 12-segment fibers with the dispersion alternatively high and low. Using this compressor and a 17 dBm Erbium-doped fiber amplifier, the 10 GHz, 12 ps pulses generated from an actively mode-locked Er3+ doped fiber ring laser was compressed to ~ 2 ps without pedestal. We also show that compared with the high order soliton pulse compressor, the power efficiency can be doubled in supercontinuum generation by using the pump pulses compressed by this CDPF compressor. | eng_Latn | 8,049 |
What is the wavelength range, I understand studies say that the optimum range is between 600 and 1000nm | As far as I can remember, my B-Cure emits a fixed wavelength of 808 nm. It seems to work well. Other laser companies say a combination of 660 and 905 nm can address deeper tissues. It's hard to know what works best.The green LED contact light periodically fails on mine (it's "on" this week), but, the red glow of the actual laser is still fine (visible in a dark room) - after 15 months of use (twice daily at 35 minutes per session) on my right knee.-Brian | According to the part's datasheet, yes. Here is the packet settings. You will limit the refresh rate with this slow baud rate. Packet Type: 251 PMTK_SET_NMEA_BAUDRATE Support Chip Type: MT3318、MT3329、MT3339 Packet Meaning： Set NMEA port baud rate Data Field： PMTK251, Baudrate Baudrate setting : 4800,9600,14400,19200,38400,57600,115200 Example： $PMTK251,38400*27<CR><LF> Note： 1. You can also restore the system default setting via issue：$PMTK251,0*28<CR><LF> 2. The setting of baud rate will be back to default value in two conditions: a. Full cold start command issued b. Enter standby mode | eng_Latn | 8,050 |
I'm trying to understand the behavior of a single laser pulse in a traditional airborne lidar. I understand that the multiple return values are representative of the surface that reflected the initial pulse. However, does a single pulse from the laser, return each reflection individually to the sensor? Or does a single pulse from the laser continue through it's path, capturing each reflection along it's way until returning to the sensor? So if a system can capture 300k pulses per second, are those 300k pulses released and captured? Or is that 100k +/- pulses returning 300k values? Example photo: Does each disturbance in the waveform return it's own pulse to the sensor? If so, how the sensor understand the laser is continuing? And if that is also true, where does the energy come from to continue the pulse further? | Can someone help with an explanation and some references, in order to understand the nature of return pulses within a LiDAR system. | I want to make it so I always have 50 entities in an area. So when 1 dies/despawns/leaves the area I want it to detect that and summon in a new entity, and yes I do want them to die/despawn/leave the area so preventing those things is not an option. | eng_Latn | 8,051 |
Ldr relay switch I'd like to build a simple ldr circuit that turn on a relay when it's dark. I've used a voltage divider composed by a ldr in series with a 10k resistor and 10k potentiometer, which drive a 2n2222 transistor, and the transistor drive a 5v relay. The input supply is 5v. Making some calculations I've find that when the ldr is ~ 1Mohm and the preset resistor fixed to 20Kohm, the voltage should be 4.902V, but the multimeter read between base and emitter is about 600mv. Why this happen? | Simplest Light triggered relay I am building a large array of Light Switched relays, and due to the size of the array i want to keep the part count down. Each 'Pixel module' has a 12V SPDT, bulb and an activate-on-dark circuit. There is a strong spotlight on the device and the viewers shadow is obscuring the light in their shadow so the swing is large. I have seen the obvious LDR-and-Pot circuits with a junction out to a NPN Transistor, and the more stable comparator alternative I was looking at "solar cell" types of Photodiodes (PiN Type), and I can't see why I cannot just lay one across a PNP transistor (Collector to Base?) or something so it applies a Base voltage when lit up. Can someone briefly explain to me why I am wrong? I figure it would be all over the net if it was that easy, and i cant find any examples! Is this possibly the cheapest way to make a light switched 12V relay driver? Note: I prefer solutions using discrete circuitry, as I have a thing for human readability, visual components etc :P | Bit error rate calculation for LIN protocol I am having this microcontroller - I am using an 8MHz external clock. I want to calculate the Bit error rate of my LIN Communication. My LIN Communication Baud rate is 19.2kbps. My questions : Can I use the LPUART Module in the Mirocontroller for the LIN Communication? How to find the Bit error rate for the LIN Protocol communication for my baud rate of 19.2kbps and external clock of 8MHz. I found this below from the reference manual. But not sure, how to calculate the Bit error rate from this. How to calculate the SBR Register value, OSR and the LPUART ASYNCH Module clock? Please help | eng_Latn | 8,052 |
BBO crystals and Polarized photons | What are the 'types' of parametric down conversion? | (Why) Has Kohonen-style SOM fallen out of favor? | eng_Latn | 8,053 |
Linear Large-Swing Push–Pull SiGe BiCMOS Drivers for Silicon Photonics Modulators | A DC-90 GHz 4-Vpp differential linear driver in a 0.13 μm SiGe:C BiCMOS technology for optical modulators | a beginner ’ s guide to partial least squares analysis . | eng_Latn | 8,054 |
>1.3-Tb/s VCSEL-Based On-Board Parallel-Optical Transceiver Module for High-Density Optical Interconnects | Terabit/s-Class Optical PCB Links Incorporating 360-Gb/s Bidirectional 850 nm Parallel Optical Transceivers | The Effectiveness of Using WhatsApp Messenger as One of Mobile Learning Techniques to Develop Students' Writing Skills. | eng_Latn | 8,055 |
A 12Gb/s, 8.6µApp input sensitivity, monolithic-integrated fully differential optical receiver in CMOS 45nm SOI process | Silicon Photonic Transceiver Circuits With Microring Resonator Bias-Based Wavelength Stabilization in 65 nm CMOS | Explainable AI for Designers: A Human-Centered Perspective on Mixed-Initiative Co-Creation | eng_Latn | 8,056 |
Packaging of silicon photonics systems | Hybrid Silicon Photonic Integrated Circuit Technology | Nerve growth factor-inducing activity of Hericium erinaceus in 1321N1 human astrocytoma cells. | eng_Latn | 8,057 |
Electrophysiology in the age of light | Advances in Light Microscopy for Neuroscience | SLM Microscopy: Scanless Two-Photon Imaging and Photostimulation with Spatial Light Modulators | eng_Latn | 8,058 |
A CDMA Modulation Technique for Automotive Time-of-Flight LiDAR Systems | Large-scale nanophotonic phased array | time - of - flight cameras : principles , methods and applications . | kor_Hang | 8,059 |
Practical Spectral Photography | Snapshot Image Mapping Spectrometer (IMS) with high sampling density for hyperspectral microscopy | Adaptive dynamic range imaging: optical control of pixel exposures over space and time | eng_Latn | 8,060 |
A 5.58 nW Crystal Oscillator Using Pulsed Driver for Real-Time Clocks | An improved low power crystal oscillator | Visual Circuits for Direction Selectivity | eng_Latn | 8,061 |
Smashing the Stack Protector for Fun and Profit | Non-control-data attacks are realistic threats | A 10Gb/s Si-photonic transceiver with 150μW 120μs-lock-time digitally supervised analog microring wavelength stabilization for 1Tb/s/mm2 Die-to-Die Optical Networks | eng_Latn | 8,062 |
Design of passive-quenching active-reset circuit with adjustable hold-off time for single-photon avalanche diodes | Reduce Afterpulsing of Single Photon Avalanche Diodes Using Passive Quenching With Active Reset | CMOS circuit testing via time-resolved luminescence measurements and simulations | eng_Latn | 8,063 |
Direct Modulation at 56 and 50 Gb/s of 1.3- $\mu $ m InGaAlAs Ridge-Shaped-BH DFB Lasers | 80ºC, 50-Gb/s Directly Modulated InGaAlAs BH-DFB Lasers | Topic Detection and Tracking using idf-Weighted Cosine Coefficient | eng_Latn | 8,064 |
A 50 Gb/s 190 mW Asymmetric 3-Tap FFE VCSEL Driver | A compact electro-optical VCSEL model for high-speed IC design | Autism spectrum disorder: Parenting stress, family functioning and health-related quality of life. | kor_Hang | 8,065 |
Piecewise Deterministic Markov Processes for Continuous-Time Monte Carlo | Riemann manifold Langevin and Hamiltonian Monte Carlo methods | Laser spotlight detection and interpretation of its movement behavior in laser pointer interface | kor_Hang | 8,066 |
A Flexible, Micro-Lens-Coupled LED Stimulator for Optical Neuromodulation. | An optical neural interface : in vivo control of rodent motor cortex with integrated fiberoptic and optogenetic technology | The role of rumination in depressive disorders and mixed anxiety/depressive symptoms. | kor_Hang | 8,067 |
Room-Temperature Near-Infrared High-Q Perovskite Whispering-Gallery Planar Nanolasers | Room-Temperature Ultraviolet Nanowire Nanolasers | A Complete Logical Calculus for Record Structures Representing Linguistic Information | eng_Latn | 8,068 |
Underwater Acoustic Modems | Aqua-Sim: An NS-2 based simulator for underwater sensor networks | Deep-space Optical Terminals ( DOT ) Ground Laser Transmitter ( GLT ) Trades and Conceptual Point Design | eng_Latn | 8,069 |
Agile Spectrum Imaging: Programmable Wavelength Modulation for Cameras and Projectors | Adaptive dynamic range imaging: optical control of pixel exposures over space and time | Reconstruction of Convolutional Encoders over GF(q) | eng_Latn | 8,070 |
A wireless photostimulator for optogenetics with live animals | MOS charge pumps for low-voltage operation | From Orthogonal to Non-orthogonal Multiple Access : Energy- and Spectrum-Efficient Resource Allocation | eng_Latn | 8,071 |
Stability and Synchronization of Discrete-Time Markovian Jumping Neural Networks With Mixed Mode-Dependent Time Delays | Finding Structure in Time | Integrating photonics with silicon nanoelectronics for the next generation of systems on a chip | eng_Latn | 8,072 |
High-capacity millimetre-wave communications with orbital angular momentum multiplexing | Orbital angular momentum of light and the transformation of Laguerre-Gaussian laser modes. | Crowd Counting and Profiling: Methodology and Evaluation | eng_Latn | 8,073 |
AXR-CMP: Architecture Support in Accelerator-Rich CMPs | Large-scale wire-speed packet classification on FPGAs | Time- and Wavelength-Division Multiplexed Passive Optical Network (TWDM-PON) for Next-Generation PON Stage 2 (NG-PON2) | kor_Hang | 8,074 |
A 40-Gb/s serial link transceiver in 28-nm CMOS technology | A Wide-Tracking Range Clock and Data Recovery Circuit | A 90nm CMOS 16Gb/s Transceiver for Optical Interconnects | eng_Latn | 8,075 |
Simultaneous two-photon imaging and two-photon optogenetics of cortical circuits in three dimensions | Closed-Loop and Activity-Guided Optogenetic Control | Implementation of Low Area and High Data Throughput CRC Design on FPGA | eng_Latn | 8,076 |
High-Voltage Modular Switched Capacitor Pulsed Power Generator | A Long-Pulse Generator Based on Tesla Transformer and Pulse-Forming Network | Elastic Bandwidth Allocation in Flexible OFDM-Based Optical Networks | eng_Latn | 8,077 |
Quality Metrics in optical modulation analysis: EVM and its relation to Q-factor, OSNR, and BER | On the Extended Relationships Among EVM, BER and SNR as Performance Metrics | Bio‐field array: a dielectrophoretic electromagnetic toroidal excitation to restore and maintain the golden ratio in human erythrocytes | eng_Latn | 8,078 |
Programmable low-complexity linear frequency discriminator for microwave photonic links (invited paper) | Software Defined Optical Networks (SDONs): A Comprehensive Survey | Hybrid Silicon Photonic Integrated Circuit Technology | eng_Latn | 8,079 |
A miniature headstage for high resolution closed-loop optogenetics | Injectable, Cellular-Scale Optoelectronics with Applications for Wireless Optogenetics | Fast burst images denoising | eng_Latn | 8,080 |
High-Performance Back-Illuminated Three-Dimensional Stacked Single-Photon Avalanche Diode Implemented in 45-nm CMOS Technology | A back-illuminated 3D-stacked single-photon avalanche diode in 45nm CMOS technology | Exposure Fusion: A Simple and Practical Alternative to High Dynamic Range Photography | eng_Latn | 8,081 |
Demonstration of an optical chip-to-chip link in a 3D integrated electronic-photonic platform | Single-chip microprocessor that communicates directly using light | Treatment of Anterior Dental Crossbite Using Bonded Resin-Composite Slopes: Case Reports | eng_Latn | 8,082 |
A Flexible, Micro-Lens-Coupled LED Stimulator for Optical Neuromodulation. | A New Individually Addressable Micro-LED Array for Photogenetic Neural Stimulation | MaskConnect: Connectivity Learning by Gradient Descent | kor_Hang | 8,083 |
Using Graph-Based Characterization for Predictive Modeling of Vectorizable Loop Nests | Using graph-based program characterization for predictive modeling | A high-speed/power laser transmitter for single photon imaging applications | eng_Latn | 8,084 |
how can laser power be measured? | Spectrometers for Laser Measurement. These miniature rugged spectrometers are calibrated to measure and track laser frequency and centroid wavelength and/or total power of lasers in Watts. Currently, StellarNet offers laser measurement systems in the 200-2300nm range. | In another experiment, he measured the frequency of an optical transition in cesium atoms (a change in their state that absorbs or emits light at a precise frequency) using a mode-locked laser to span the difference in frequency between two CW lasers. His results inspired a group of us to undertake serious research in this arena. | eng_Latn | 8,085 |
what are fiber lasers | From Wikipedia, the free encyclopedia. A fiber laser or fibre laser is a laser in which the active gain medium is an optical fiber doped with rare-earth elements such as erbium, ytterbium, neodymium, dysprosium, praseodymium, and thulium.They are related to doped fiber amplifiers, which provide light amplification without lasing.any high-power fiber lasers are based on double-clad fiber. The gain medium forms the core of the fiber, which is surrounded by two layers of cladding. The lasing mode propagates in the core, while a multimode pump beam propagates in the inner cladding layer. The outer cladding keeps this pump light confined. | Fiber. 1 Fiber optic technology converts electrical signals carrying data to light and sends the light through transparent glass fibers about the diameter of a human hair. Fiber transmits data at speeds far exceeding current DSL or cable modem speeds, typically by tens or even hundreds of Mbps. | eng_Latn | 8,086 |
what laser uses a repeat pulse mode | A mode-locked laser is capable of emitting extremely short pulses on the order of tens of picoseconds down to less than 10 femtoseconds. These pulses will repeat at the round trip time, that is, the time that it takes light to complete one round trip between the mirrors comprising the resonator. | Many researches have shown that femtosecond laser pulsing brings these benefits to LA-ICP-MS analysis: Non-thermal mass ablation such as Coulomb explosion and direct chemical bond breaking that represents the true chemistry of the sample and is conducive in reducing the elemental/isotopic fractionation. | eng_Latn | 8,087 |
what is pwm digital signal | To PWM, or not to PWM, That is the Question. Pulse width modulation (PWM) is a fancy term for describing a type of digital signal. Pulse width modulation is used in a variety of applications including sophisticated control circuitry. A common way we use them here at SparkFun is to control dimming of RGB LEDs or to control the direction of a servo motor. | The PWM deals with timing instead of voltage so any common-mode voltage shift across the isolation barrier does not affect the signal. The PWM signal will be very robust to noise since it is either a 0 or a 1 instead of a small analog voltage. A class-D amplifier is a very inexpensive way to convert analog to PWM. | eng_Latn | 8,088 |
Active neutrino oscillations and the SNO neutral current measurement | We discuss the relation between the observed CC, ES, and NC fluxes with the flavor fractional content of the solar neutrino flux seen by SNO. By using existing estimates of the cross sections for the charged and neutral current reactions which take into account the detector resolution, we show how the forthcoming SNO rates unconstrained by the standard $^8$B shape could test the oscillations into active states. We perform a model independent analysis for the Super-K and SNO data, assuming a non distorted spectrum. | We review recent methods to increase the speed of the nonlinear optical response of semiconductor optical amplifiers (SOAs), including the use of filters and of an additional SOA in the 'turbo-switch' configuration. We also consider the effects of optimising parameters, such as the confinement factor and optical area, on the recovery rate. | eng_Latn | 8,089 |
Real-time MPEG-1 video transmission over local area networks | In this work is presented the architecture of an MPEG-1 stream transmission system appropriate for point-to-point transfer of live video and audio over TCP/IP local area networks. The hardware and software modules of the system are presented as well. Experimental results on the statistical behavior of the generated and transmitted MPEG-1 stream are quoted.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only. | Summary form only given. We have demonstrated a short-pulse optical interconnect that uses a practical, high-repetition-rate modelocked source. BER measurements show that operation with short pulses improves system performance by providing a receiver sensitivity enhancement of 3.3 dB. The link has additional benefits related to timing issues and latency reduction. | eng_Latn | 8,090 |
A 0.6V CMOS Image Sensor with in-pixel biphasic current driver for biomedical application | A 0.6V pulse frequency modulation (PFM) CMOS Image Sensor (CIS) array with in-pixel biphasic current pulse driver is presented in this paper. It achieves a photon-to-biphasic current conversion for biomedical applications like artificial 2-D vision recovery. The photon-to-biphasic-current conversion gain, the biphasic pulse width, polarity, and output rate are all tunable depends on applications and environments. A 32×32 pixel array with 30×30 um2 pixel size has been designed and fabricated in 0.18um CMOS technology providing the fill factor of 24.5%. Measurement results show a 0.63Hz/lux conversion gain of PFM sensor within 25hz∼5kHz output with power consumption as 2uW∼55uW depends on illumination. The maximum driving capability of biphasic neural stimulation current pulse is ±20µA with a 10kΩ electrode model. | Remote control learning type with a circuit which is connected to a supply voltage, the circuit comprising: a) an infrared (IR) diode, said IR diode being sensitive to received light, and is capable of / voltages in response to the received light to generate photocurrents; b) a switch responsive to an associated drive signal, said switch selectively connects the IR diode with the supply voltage and separates therefrom, to provide an output IR signal in response to the drive signal; and c) an amplifier connected to said IR diode to photocurrents / voltages to supply in response to light which is directed to the IR diode, said IR diode only functions as a light receiver when the switch the IR diode switches off so that it does not respond to the drive signal. | eng_Latn | 8,091 |
A Novel Device Controlling the Output of Excimer Lasers | The average power emitted by an excimer laser is the product of pulse energy and repetition frequency. The pulse energy depends on several factors, most important of which, for a given laser, are the electrical energy coupled into the discharge, the gas mixture, and the quality of the optical resonator. | Aiming at the requirements in running efficiently and high accuracy handling data timely,the login system,communication module,database storage and reading,relay verification module,report generation and printing.were designed.The working principle and composition of the calibration device were introduced.The upper computer software of microprocessor relay protection's trippingoperation-board intelligent calibration device was developed based on graphical LabVIEW language and database programming technology to realize the function of each part.The results indicate that the software can complete returning the relay operating board calibration value and action value efficiently,and has a multi-function interface.The software has been successfully applied in this device. | eng_Latn | 8,092 |
Fraktionierte Lasersysteme : Ein Erfahrungsbericht 2008 | The paper shows our experience with the different fractional lasers. Fractional CO 2 -lasers shows greatest effects but also causes the longest down time. Further studies must evaluate the best treatment parameters for the different lasers. | Thank you very much for downloading automated systems based on human skill 2000 joint design of technology and organisation a proceedings volume from the 7th ifac symposium aachen germany 15 17 june 2000. Maybe you have knowledge that, people have look numerous times for their favorite readings like this automated systems based on human skill 2000 joint design of technology and organisation a proceedings volume from the 7th ifac symposium aachen germany 15 17 june 2000, but end up in harmful downloads. Rather than enjoying a good book with a cup of coffee in the afternoon, instead they cope with some infectious bugs inside their desktop computer. | deu_Latn | 8,093 |
Dual-frequency comb spectroscopy: A digital solution for coherent averaging | We present a dual-comb spectrometer in which a new digital solution allows long-time coherent averaging of molecular spectra without spectral distortion even when the combs are free-running and subject to frequency drifting and jittering. | This paper considers a method to realize a two-valued input three-valued output function f:{0, 1}/sup n//spl rarr/{0, 1, 2} by using a cascade of four-input cells. Decomposition of a group function is used to find a canonical form. We show that the Walsh spectrum specifies the canonical form, and the number of non-zero coefficients in the spectrum is proportional to the number of cells in the cascade. Finally, we show a design algorithm for a p-valued function f:{0, 1}/sup n//spl rarr/{0, 1, ..., p-1}. The designed cascades are reversible and conservative. | eng_Latn | 8,094 |
Photonic digital-to-analog conversion and M-PAM signal generation via direct-digital-drive microring modulator | Attempting to apply photonic technologies to data processing has been taking place for several decades. Yet, their implementation in practical systems remained limited and failed to penetrate practical processors. Many demonstrated optical devices remained oversized, were based on exotic materials and needed rather complicated interfacing with other electronic components. | The invention discloses an MVB device status word transmission method based on load balance. Before bus resource allocation, all cyclic loads in a whole macrocycle are calculated according to allocation of application ports, calculation results are sequenced from small to large, and roll poling of a device status word is inserted in a low-load cycle in a single cycle according to the sequencing result. The method has the advantages that the principle is simple, network loads can be optimized, and correctness and stability of device state display are guaranteed. | eng_Latn | 8,095 |
Why does AAXA not explicity state the native resolution for this device? It says it "ACCEPTS" 1080p inputs which means nothing. Website doesn't say. | This is a fairly simple projector and although it accepts 1080p inputs, it may not actually be intended for HD resolution display. It works well with about an hour charge. Nice size. Does need a fairly dark room. Good for a spare projector for small room. I actually purchased for Halloween gimmick. | Looks like the filter is rated at 10 amps which I would consider the maximum continuous current. A 'brief' spike to 13 amps in my opinion should be tolerated. For $30, if you are having X10 problems and think it is your PC equipment, then trying the filter is worth it. Also, you could put everything else on the filter and leave your laser printer plugged directly into an outlet. That might be a good first step in experimenting how to solve your X10 problems. | eng_Latn | 8,096 |
Is it possible to get a push button switch for the flashlight similiar to the push button switch for the laser? | Thank you for writing. It does not look like you can get a push button switch like the laser. I looked for one but did not see them. | I bought two pkgs -- total 6 units, 2 remotes. I use one set in the living room and one set in a bedroom 25-30 feet away. The living room remote did not turn on the bedroom lights. However, it did turn on the living room lights, so it was interesting to learn the remote will activate lights from some distance away. Could be useful to illuminate your pathway from one room to another in the dark. So, from my experiment, I'd say there is no "crosstalk." | eng_Latn | 8,097 |
Does the PLAiR 2 work with the Plex media server? | Yes. Plex is fully compatible with PLAiR and is very popular among PLAiR users. | it should, if the gun has a Weaver/picatinny rail. But I wouldn't waste my money, it's not a very good laser. | eng_Latn | 8,098 |
Does this SSR provide optical isolation between the control inputs and the line outputs? | The low level inputs are optically coupled to the high power switched side. Note this switch is only suitable for AC as it appears to be an optically coupled TRIAC and will latch with DC. | sorry for the delayed reply , had to pull it out of the closet and examine it.yes the attached "v"yoke is removable , I use mine for laser bore sighting rifle scopesand it works fantastic , easy to set up , light but well constructed.it will support ans stabalize a 30.06 deer rifle hunting from a blind.hope this helps.... | eng_Latn | 8,099 |
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