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991.
A holographic screen that makes it possible to display 3D images by the method of point-focused aspects (of a scene to be displayed) or by projecting narrow line holograms is suggested and implemented. The image thus formed reconstructs only horizontal parallax, which allows one to cut the body of information necessary for 3D imaging. Projection through the screen and a way of recording the screen are considered. 相似文献
992.
Huang H. X. Liang Z. A. Pardalos P. M. 《Journal of Optimization Theory and Applications》2004,120(1):53-71
A flow search approach is presented in this paper. In the approach, each iterative process involves a subproblem, whose variables are the stepsize parameters. Every feasible solution of the subproblem corresponds to some serial search stages, the stepsize parameters in different search stages may interact mutually, and their optimal values are determined by evaluating the total effect of the interaction. The main idea of the flow search approach is illustrated via the minimization of a convex quadratic function. Based on the flow search approach, some properties of the m-step linear conjugate gradient algorithm are analyzed and new bounds on its convergence rate are also presented. Theoretical and numerical results indicate that the new bounds are better than the well-known ones. 相似文献
993.
Equations that simulate the magnetic induction and current density distributions in half-space in view of the power I-V characteristic are derived. The magnetization front velocity is determined for a given mean rate of external magnetic field variation at the boundary of the sample. An integral condition for the electrical resistance (nonlinearly depending on the magnetic field) under which the magnetic flux penetrates into the sample with a finite rate is found. An analytical solution that simulates the power variation of the magnetic field at the boundary is given. The Bean generalized model describing the current density distribution near the critical current is considered. It is shown that solutions like shock waves may arise beyond the applicability domain of the Bean model. 相似文献
994.
V. A. Varlachev G. N. Dudkin Yu. F. Krechetov V. N. Padalko E. N. Shuvalov 《JETP Letters》2004,80(3):149-151
A nuclear-reactor experiment on the search for the emission of neutral pions from the neutron-induced fission of 235U nuclei has been carried out. To this end, an experimental setup for searching for the emission of π0 mesons with high sensitivity to this process has been designed and produced. This setup consisted of two Cherenkov total-absorption spectrometers for the detection and measurements of the energy of two gamma-ray photons from π 0-meson decay. The spectrometers were placed at the exits of two coaxial horizontal experimental channels. To protect the detectors from low-energy β and γ rays and neutron fluxes, 3.5-m-long water filters were situated in the channels. To reject the cosmic background, large-area scintillation counters operating in the anticoincidence mode were placed over each spectrometer. The energy and time resolution of the spectrometers, as well as the efficiency of detecting charged particles by scintillation counters, were tested on the secondary electron beam of the Tomsk electron synchrotron Sirius. Runs of measurements of the effect on the operating reactor (duration of 805 h) were alternated with runs of measurements of background on the stopped reactor (duration of 403 h). Statistical processing of the experimental results yields an upper limit of ≤5.3×10 ?12 with a 90% confidence level for the probability of the emission of neutral pions from the neutron-induced fission of 235U nuclei. This result and results of other works carried out with sources of spontaneously fissioning 252Cf nuclei show that the probabilities of the emission of π0 mesons from spontaneous fission and fission induced by fission-spectrum neutrons are equal to each other. 相似文献
995.
996.
V. Yu. Mat’ev 《Technical Physics》2003,48(3):303-310
The distribution of the two-dimensional gas velocity inside ion-irradiated laser cells is considered for low ion energy deposits into the gas. It is shown that, if the energy deposit is smoothly nonuniform, the twodimensional motion has two quasi-one-dimensional components: the longitudinal gas velocity is practically uniform across the cell and depends on the transversely averaged energy deposit, while the transverse velocity component depends on the difference between the local energy deposit and energy deposit averaged over the transverse direction. 相似文献
997.
Clifford algebra corresponds to Minkwoski space. The coupling between real object particles and light quantums can be discussed
by Minkowski space’s directional strangeness. We introduce Galilei transfomation and Schr?dinger equation into Minkowski space
and give a geometrical explanation for classical quantum theory. 相似文献
998.
Chongyi Wan Shiming Liu Rongqing Tan Jin Wu Jinwen Zhou Yan Lv Yanning Yu Hua Yang 《Optics & Laser Technology》2004,36(8):2389-649
A high average power, high-repetition-rate TEA CO2 laser employing printed-circuit-board preionizer is described. The power scaling of this preionization configuration has been demonstrated. The average output power reaches 3.6 kW at pulse repetition rate of 180 pps. Furthermore, the scaling-up ability of the rotating spark gap as high-voltage switch for high-average-power gas laser has been validated. 相似文献
999.
We study the critical temperature T
c of FSF trilayers (F is a ferromagnet, S is a singlet superconductor), where the triplet superconducting component is generated
at noncollinear magnetizations of the F layers. An exact numerical method is employed to calculate T
c as a function of the trilayer parameters, in particular, mutual orientation of magnetizations. Analytically, we consider
limiting cases. Our results determine the conditions necessary for the existence of recently investigated odd triplet superconductivity
in SF multilayers. 相似文献
1000.
Yu. S. Gordeev V. V. Bryzgalov B. N. Makarenko V. M. Mikushkin S. G. Konnikov P. N. Brunkov V. M. Ustinov A. E. Zhukov 《Technical Physics》2003,48(7):885-888
The modification of GaAs with a 2500-eV beam containing N 2 + and Ar+ ions is examined with Auger electron spectroscopy. Most implanted nitrogen atoms are found to react with the matrix, substituting arsenic atoms to produce a several-nanometer-thick layer of the single-phase GaAs1−x Nx (x=6%) solid solution. The GaN phase is absent. Displaced arsenic atoms and nitrogen atoms unreacted with the matrix are present in the layer and on its surface. The former segregate, whereas the latter form molecules. 相似文献