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A thick-layer light-sensitive material consisting of glycerin-containing bichromated gelatin has been prepared and used to record real-time volume holograms with 0.44 μm helium-cadmium laser radiation. The thickness of the layers is 400–600 μm. The holographic sensitivity of the material is 1 J/cm2. The highest diffraction efficiency of holograms recorded using a symmetric system with parallel beams is 32%. Pis’ma Zh. Tekh. Fiz. 23, 62–65 (April 12, 1997)  相似文献   
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Examined the theory that chronic migraine headaches can lead to permanent changes in brain function in 71 female college students. Ss were 20 classic migraineurs, 27 common migraineurs, and 24 controls. No significant group differences were found on the Halstead Reitan Neuropsychological Test Battery and additional memory tests. Classic migraineurs had significantly higher scores than common migraineurs on the Hysteria and Paranoia scales of the Minnesota Multiphasic Personality Inventory (MMPI) and significantly higher scores than the controls on Hypochondriasis and Hysteria scales. Explanations for the lack of cognitive deficits in this group are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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A new diffuser capable of scattering light in one direction (one-dimensional diffuser) has been developed and experimentally tested. The diffuser is formed in a thick layer of dichromated gelatin. The scattering indicatrices of the diffuser measured in two mutually perpendicular directions are presented. It is demonstrated that the indicatrix width in one direction is significantly greater than that in the perpendicular direc-tion. However, no zero-order diffraction has been observed. The proposed one-dimensional diffuser exhibits close scattering indicatrices for reading at a wavelength of 0.44 and 0.63 μm.  相似文献   
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Übersicht Um die Betriebssicherheit großer supraleitender Magnetsysteme für die Kernfusionsforschung zu gewährleisten, muß die im Magnetsystem gespeicherte Energie schnell entladen werden können. Durch die veränderlichen großvolumigen Magnetfelder werden in benachbarten leitfähigen Strukturen durch Induktion hohe Wirbelströme hervorgerufen. Durch sie treten dort elektromagnetische Kräfte. auf, die einzelne Komponenten mechanisch überlasten können. Zur Berechnung dieser Kräfte wurde eine einfache numerischanalytische Methode entwickelt, die im folgenden vorgestellt und mit Finite-Elemente-Verfahren verglichen wird.
Calculation of eddy current densities and forces around large superconducting coils for nuclear fusion
Contents The reliable operation of the superconducting magnet systems used for the magnetic confinement in nuclear fusion research requires the ability of a fast discharge of the stored magnetic energy. The corresponding magnetic field variation gives rise to high eddy currents by inductive coupling with surrounding conductive components. The eddy current forces can lead to a mechanical overload of some of these components. A simple numerical-analytical method was developed in order to calculate these forces. This method is presented and compared with the Finite Element Method.
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We give a parametrized family of rational interval maps of degree two, each ergodic, exact and preserving a measure equivalent to a Lebesgue measure. The family includes the unique quadratic Chebyshev polynomial as its only polynomial map. We extend the family to other settings on the circle and real line. We also give numerical approximations to the entropy of the equivalent invariant measure and the Hausdorff dimension of the singular measure of maximal entropy.  相似文献   
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In this article it is argued that in ten years’ time personal computers as we know them now won’t exist anymore — all their functions will by then be integrated in mobiles which will be our steady companions. As such, mobiles will change our lives to an enormous extent. Technology as well as consequences will be discussed in this paper.  相似文献   
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Examined perceived environment, perceived incentive and outcome, and person constructs for relationships with interest and participation in voluntary learning and development activity by nonmanagement employees. All 3 groups of constructs were related to development activity. In relationships with development activity, perceived outcome and environment variables interacted with workers' personal values relevant to aspects of a development setting, illustrating the potentially important role that differences in values may play in a development context. Additionally, small relationships were observed between several demographic variables and values within a development setting. Results provide implications for the design and implementation of successful development programs and highlight the need to carefully consider individual differences in this context when targeting many different types of employees for participation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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