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Abstract— V‐shaped electro‐optical response is shown, both theoretically and experimentally, to be an inherent property of a deformed‐helix ferroelectric liquid‐crystal cell (DHFLC) under a special choice of the applied rectangular alternating‐electric‐field waveform, frequency, and cell geometry. In contrast to other known V‐shaped ferroelectric liquid‐crystal (FLC) modes, the discovered V‐shaped switching is observed in a broadband frequency range including 1 kHz, and not at a certain characteristic frequency. This type of V‐shaped switching allows for a drastic increase in the operating frequency of field‐sequential‐color (FSC) LCD cells in comparison with fast nematic liquid‐crystal (NLC) modes.  相似文献   
104.
Abstract— The plasma‐beam alignment procedure earlier developed for the alignment of nematic liquid crystals is successfully extended to ferroelectric liquid crystals (FLC). The highly uniform alignment of the “chevron” structure (before electrical treatment of FLC cells) and “quasi bookshelf” structure (after the electrical treatment) are realized. The contrast of bistable switching larger than 350:1 is achieved. This makes the non‐contact plasma‐beam alignment procedure especially attractive for high‐contrast bistable LCDs on an LCOS base, particularly used in PDA and e‐books. Fast switching and realization of gray scale in the plasma‐beam aligned FLC cells makes this technique also promising for full‐color displays including color LCD TV.  相似文献   
105.
Field and experimental investigations as well as full-scale tests of foundations and artificial bases in punched (tamped-out) trenches at specific projects in South Kazakhstan have once again confirmed the effectiveness of their application in seismic regions with similar soil conditions.Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 6, pp. 37–39, November–December, 1992.  相似文献   
106.
In this article a mathematical model of forests impact on aquifers is proposed. This phenomenon is the lowering of the groundwater table under areas covered by trees. The model includes a boundary-value problem with contact and free-boundary conditions. A variational formulation of this problem, which is a quasi-variational inequality, is obtained. Its equivalence with the original problem is proved; existence and uniqueness results are obtained. A numerical example of the model is given.  相似文献   
107.
The vortex structure in high-T c superconductors is investigated on the basis of the anisotropic structures of these materials. An analysis is developed in order to determine the GinzburgLandau expression of the free energy for the layered structure. The two cases of(T)d and(T)d corresponding to the existence of Abrikosov and Josephson vortex types are discussed.  相似文献   
108.
The problem of light scattering by ice crystal particles whose sizes are essentially larger than the incident wavelength is divided into two parts. First, the scattered field is represented as a set of plane-parallel outgoing beams in the near zone of the particle. Then, in the far zone the scattered field is represented as a result of both diffraction and interference of these beams within the framework of physical optics. A proper ray-tracing algorithm for calculation of the amplitude (Jones) scattering matrix is developed and applied. For large particles, a number of reduced Mueller matrices are introduced and discussed, since the pure Mueller matrix obtained from the Jones matrix becomes a rather cumbersome and quickly oscillating value. Backscattering by hexagonal ice crystals, including polarization properties, is considered in detail.  相似文献   
109.
This article introduces ATR's CAM-Brain Machine (CBM), an FPGA based piece of hardware which implements a genetic algorithm (GA) to evolve a cellular automata (CA) based neural network circuit module, of approximately 1,000 neurons, in about a second, i.e. a complete run of a GA, with 10,000 s of circuit growths and performance evaluations. Up to 65,000 of these modules, each of which is evolved with a humanly specified function, can be downloaded into a large RAM space, and interconnected according to humanly specified artificial brain architectures. This RAM, containing an artificial brain with up to 75 million neurons, is then updated by the CBM at a rate of 130 billion CA cells per second. Such speeds should enable real time control of robots and hopefully the birth of a new research field that we call brain building. The first such artificial brain, to be built by ATR starting in 2000, will be used to control the behaviors of a life sized robot kitten called Robokoneko.  相似文献   
110.
A key factor to the implementation of devices with vertically aligned carbon nanofibers (VACNFs) is fundamental understanding of how to control fluctuations in the growth direction of the fibers. Here we demonstrate synthesis of VACNF on transparent and insulating substrates by continuous direct current (DC) plasma for realization of cellular interface suitable for transmission optical microscopy. To maintain continuous glow discharge above the substrate, a metal grid electrode layer (Cr) was deposited over silica with windows of exposed silica ranging in size from 200 μm to 1 mm. This electrode geometry allows for synthesis of VACNFs even within an insulating window. This observation and the observed trends in the alignment of nanofibers in the vicinity of grid electrodes have indicated that the alignment does not correspond to the direction of the electric field at the substrate level, contrary to previously proposed alignment mechanism. Computational modeling of the plasma with this grid cathode geometry has shown that nanofiber alignment trends follow calculated ion flux direction rather than electrical field. The new proposed alignment mechanism is that ion sputtering of the carbon film on a catalyst particle defines the growth direction of the nanofibers. With this development, fiber growth direction can be better manipulated through changes in ionic flux direction, opening the possibility for growth of nanofibers on substrates with unique geometries.  相似文献   
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