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891.
New minimax inequality with applications to existence theorems of equilibrium points 总被引:4,自引:0,他引:4
A new minimax inequality is proved on a set which is the union of an increasing sequence of compact convex sets in a topological vector space. As applications, several existence theorems of equilibrium points for different games are obtained.The authors would like to thank the referees for their helpful suggestions. 相似文献
892.
A new numerical method is proposed to solve the Boltzmann equation. A frame is set up by using a discrete velocity approximation in the infinite velocity space, but by considering only those distribution function points which are not too small. The distribution function points may occur anywhere in the infinite discrete velocity space and are not constrained to a pre-specified region. A fourth-order finite difference is used for the convection terms. A Monte Carlo-like method is applied to the discrete velocity model of the collision integral. The effort of the method is proportional to the number of discrete points. Numerical examples are given for the full Boltzmann equation and results for some benchmark problems are compared with analytical or prior solutions. 相似文献
893.
A DC-contact MEMS shunt switch 总被引:3,自引:0,他引:3
This paper presents the design, fabrication, and performance of a metal-to-metal contact micro-electro-mechanical (MEMS) shunt switch. The switch is composed of a fixed-fixed metal beam with two pull-down electrodes and a central DC-contact area. The switch is placed in an in-line configuration in a coplanar waveguide transmission line. This topology results in a compact DC-contact shunt switch and high isolation at 0.1-18 GHz. The isolation at MM-wave frequencies is limited by the inductance to ground and is -20 dB at 18 GHz. The application areas are in wireless communications and high-isolation switching networks for satellite systems 相似文献
894.
热象无损检测技术应用 总被引:1,自引:1,他引:0
本文将热象无损检测技术应用于鉴定受测物结构和性质,并测出受测物中的缺陷,实验结果取得了较为满意的进展。 相似文献
895.
896.
897.
Smy T. Tan L. Chan K. Tait R.N. Broughton J.N. Dew S.K. Brett M.J. 《Electron Devices, IEEE Transactions on》1998,45(7):1414-1425
Modified sputtering techniques, such as long throw sputtering, collimation, and ionized sputtering, have been proposed to improve VLSI topography bottom coverage by narrowing the angular distribution of the sputter flux at the substrate and reducing subsequent flux shadowing at the bottom of topography. This paper first investigates a number of unique aspects involved in the simulation of long throw sputter systems. In particular, time importance of inhomogeneous film density and nonunity sticking coefficients are addressed. The second part of the paper presents a simulation study of long throw sputtering, providing a comparison to collimated and standard sputtering systems. The simulations are performed using the SIMSPUD/SIMBAD ballistic deposition tool. SIMSPUD is used to study film uniformity over a 300-mm wafer and to generate angular distributions at the center and edge of the wafer. The ability of SIMBAD to simulate directed sputtering systems is verified by direct comparison to Ti films deposited into oxide trenches. The importance of modeling the film microstructure is demonstrated by comparison between cross-sectional SEM's micrograph for evaporation and modeling results, such as long throw sputtering with a variety of substrate/target spacings, typical “standard” as well as “collimated” systems. SEM's of overhang structures and simulations are also presented to demonstrate nonunity sticking during the co-sputtering of TiW 相似文献
898.
H. S. Tan M. K. Han P. Y. Hu J. H. Zheng S. C. Ng H. Gong 《Applied Physics A: Materials Science & Processing》1994,59(3):245-251
An electron trap having an energy level of 0.14 eV from the conduction band edge was found in the bulk of copper-diffused VPE-grown n-GaAs0.6P0.4 by conventional DLTS measurements and by pulse-duration dependent capacitance amplitude measurements. The capture cross section at room temperature is about 1.0×10–21 cm2 and has a weak temperature dependence. These properties are attributed to a non-repulsive center having a capturing mechanism which involves multiphonon emission processes with hardly any lattice relaxation. Evolution of the spatial distributions of the traps with time under junction electric field were studied. The results suggest that the trap is positively charged and has a high diffusivity under electric field. The center can thus be identified as positively charged interstitial copper ion rather than some form of copper complexes. 相似文献
899.
900.