Electrical responses to greater superficial petrosal (GSP) nerve stimulation in a rat geniculate ganglion (GG) preparation were assessed by simultaneous multi-site optical recording. The GG/GSP nerve preparations were...
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Electrical responses to greater superficial petrosal (GSP) nerve stimulation in a rat geniculate ganglion (GG) preparation were assessed by simultaneous multi-site optical recording. The GG/GSP nerve preparations were dissected out and were stained with a voltage-sensitive dye (rH155). Application of depolarizing square pulses to the GSP nerve fibers using a suction electrode evoked optical (absorbance) signals that were recorded simultaneously from many contiguous regions using a 24 x 24 photodiode matrix array with 448 active elements. Those optical signals were observed along the left half area of the GSP nerve. As the distance from the site of stimulation increased, the optical signals appeared to conduct with increasing time-delay. From the relationship between the peak latency anddistance, the conduction velocity was estimated to be about 0.4 m/s. Tetraethylammonium affected the duration of the optical signals, and the signals disappeared in solutions containing tetrodotoxin (TTX) or in Na+-deficient solutions. The optical signals evoked by the: GSP nerve stimulation are considered to be due to the action potentials propagating along the GSP of unmyelinated axons. (C) 1997 Elsevier Science Inc.
We have developed a new image stabilization method that utilizes electric charge transfer in the vertical transferregister of a CCd image sensor. This methodrepeats a series of actions including one or more continuo...
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ISBN:
(纸本)9781424407620
We have developed a new image stabilization method that utilizes electric charge transfer in the vertical transferregister of a CCd image sensor. This methodrepeats a series of actions including one or more continuous exposures according to the degree of camera shake, transferring and adding electric charges in the vertical transferregister to correct image blurs. Since this technique does not require mechanical components, external memory ordigital image processing circuits, it allows cameras to be miniaturized and costs reduced.
rotor speed estimation for induction motors is a key problem in speed-sensorless motordrives. This paper performs nonlinear high gain observerdesign based on the full-order model of the induction motor. Such an effo...
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rotor speed estimation for induction motors is a key problem in speed-sensorless motordrives. This paper performs nonlinear high gain observerdesign based on the full-order model of the induction motor. Such an effort appears nontrivial due to the fact that the full-model at best admits locally a non-triangular observable form(NTOF), and its analytical representation in the NTOF can not be obtained. This paper proposes an approximate high gain estimation algorithm, which enjoys a constructive design, ease of tuning, and improved speed estimation and tracking performance. Experiments demonstrate the effectiveness of the proposed algorithm.
To improve the situation for crowded commuters in Japan, it is important to plan a train schedule that considers passenger behavior, such as their choice of trains and the transfer stations used to reach theirdestina...
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ISBN:
(纸本)1845641779
To improve the situation for crowded commuters in Japan, it is important to plan a train schedule that considers passenger behavior, such as their choice of trains and the transfer stations used to reach theirdestinations. However, it is difficult to directly measure such detailed behavior using the present infrastructures, with which we can only get Od (Origin-destination) data from the automatic ticket gates. The obtained Oddata only consists of the number of passengers for each origin-destination and the time each passenger passes through the gates. In this article, to contribute to the planning phase of a new train schedule, the authors propose a method for estimating railway passenger flow using Oddata. This paper firstly points out that the problems of estimating passenger flow can be boileddown to a shortest path problem of graph theory by assuming a certain passenger behavior model. By representing train operations in a graph structure, we can assume that a passenger will use the minimum cost path to his/herdestination. This paper secondly proposes a method for conducting fast searches of the graph structure. The method uses the fact that railways operate on a time schedule. This method can estimate passenger flow fast enough so as to apply it to a practical train schedule planning support system. Lastly, the authors show the results of applying the passenger flow estimation system to a railway in an urban area in Japan.
Global vehicle electrification is accelerating to combat global warming. recently, Silicon Carbide (SiC) Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) are increasingly used in electric vehicle inverters...
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ISBN:
(数字)9798331516116
ISBN:
(纸本)9798331516123
Global vehicle electrification is accelerating to combat global warming. recently, Silicon Carbide (SiC) Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) are increasingly used in electric vehicle inverters for their low power loss at fast switching speeds compared to conventional Silicon Insulated Gate Bipolar Transistors (IGBTs). Although SiC MOSFETs are usually used in parallel to gain power, these fast-switching speeds can lead to gate voltage oscillations across paralleled SiC chips, potentially leading to failures such as gate drive malfunction and gate oxide breakdown. This paper addresses the oscillation caused by source voltage fluctuations and unbalanced gate drive circuit characteristics. We propose a method to mitigate these issues using a symmetrical module structure which equalizes stray inductance between modules.
Evolution of etched profiles has been numerically studiedduring low-pressure, high-density (LPHd) plasma etching of Si in Cl-2. The surface etch rates were calculated using a reaction model of synergism between incom...
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Evolution of etched profiles has been numerically studiedduring low-pressure, high-density (LPHd) plasma etching of Si in Cl-2. The surface etch rates were calculated using a reaction model of synergism between incoming ions and neutral reactants, including the spread of ion angulardistributions due to their thermal motions and the transport of neutrals arising from the reemission on surfaces in a microstructure. Etched profiles were then simulated using a so-called two-dimensional string algorithm to examine the effects of ion temperature kT(i) and energy (or sheath voltage) eV(s) on the etch anisotropy fordifferent neutral-to-ion flux ratios Gamma(n)/Gamma(i) toward the substrate. Numerical results indicated that in typical Cl-2 LPHd plasma etching environments, where the neutral-to-ion flux ratio is Gamma(n)/Gamma(i) similar to 1 and the ratio of sheath voltage to ion temperature is eV(s)/kT(i) similar to 100, the chlorinated surface coverage is microscopically nonuniform in etched features: The coverage is very low at the bottom (alpha similar to 0.1), whereas the sidewall surface (alpha similar to 1) is almost saturated with neutrals. This microscopic nonuniformity of the coverage in etched features is the proposed mechanism responsible for the inversely tapered profiles that often occur in LPHd plasma etching. Additionally, the decrease in vertical etch rate in microstructures or the reactive-ion-etching lag due to neutral shadowing effects is also found to become significant in LPHd plasma etching. At such a low flux ratio of Gamma(n)/Gamma(i) similar to 1, more directional ions with a higherratio of eV(s)/kT(i) greater than or similar to 500 are required for the anisotropic etching;e.g., for an ion energy (or sheath voltage) of eV(s) = 50 eV, the ion temperature in a plasma is required to be kT(i) less than or similar to 0.1 eV. (C) 1997 American Institute of Physics.
We report on a compact InGaAsP/InP MQW directional coupler switch with spacing between the waveguides at the input and the output facets larger than 125 mum, required for the fiber-array coupling, by employing small a...
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We report on a compact InGaAsP/InP MQW directional coupler switch with spacing between the waveguides at the input and the output facets larger than 125 mum, required for the fiber-array coupling, by employing small and low-loss bends. The total device length, including both the coupling and the bending regions, with the different optical confinements in the lateral direction is 2 mm. The coupling region of the switch is 420 mum, and the voltage-length product at switching is around 6 Vmm.
The polarisation independent refractive index change in the tensile strained InGaAs/InGaAsP quantum well (QW) structure has been measured over the whole spectral range, i,e. near and below the bandgap energy. By induc...
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The polarisation independent refractive index change in the tensile strained InGaAs/InGaAsP quantum well (QW) structure has been measured over the whole spectral range, i,e. near and below the bandgap energy. By inducing a 0.3% tensile strain in the InGaAs QW, the spectral profiles for the TE and TM modes are brought closer to each other, with the same refractive index change occurring at around 1.565 mum.
作者：
Taek Soo Kim J K Lee H J Kim J C BaeAdvanced Materials R&D Center
Korea Institute of Industrial Technology994-32 Dongchun-dongYeonsu-kuIncheon 406-130Korea Advanced Materials R&D CenterKorea Institute of Industrial Technology994-32 Dongchun-dongYeonsu-kuIncheon 406-130Korea Advanced Materials R&D CenterKorea Institute of Industrial Technology994-32 Dongchun-dongYeonsu-kuIncheon 406-130Korea Advanced Materials R&D CenterKorea Institute of Industrial Technology994-32 Dongchun-dongYeonsu-kuIncheon 406-130Korea
Glass forming ability (GFA) and structural characterization of a new amorphous Al-Ni-Sr alloy melt spun were investigated on the theory of the factors for the glass formation. The GFA was varied with the ratio of Ni t...
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Glass forming ability (GFA) and structural characterization of a new amorphous Al-Ni-Sr alloy melt spun were investigated on the theory of the factors for the glass formation. The GFA was varied with the ratio of Ni to Sr in detail and successful amorphous phase dispersed with 2 ～ 5 nm precipitates was prepared from Al-Ni5-Sr3. Thermal stability and crystallization behavior of the amorphous phase were determined by continuous and isothermal heating technique on dCS, resulting that the crystallization occurs by the growth of fcc Al nanocrystals on the preexistent nuclei.
In this paper, an advanced fast channel tracking method is proposed for automotive dTV receiver. The auto channel tracking function tunes an alternative broadcaster which belongs to affiliation group automatically, wh...
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ISBN:
(纸本)9781424407620
In this paper, an advanced fast channel tracking method is proposed for automotive dTV receiver. The auto channel tracking function tunes an alternative broadcaster which belongs to affiliation group automatically, when channel condition is getting worse. Auto channel tracking is a practical approach to support comfortable reception. The proposed method substantially improves the channel tracking speed. The advantage of the proposed method is confirmed by an experiment.
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