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71.
质子和中子的单粒子效应等效性实验研究 总被引:1,自引:0,他引:1
通过实验方法确定了高能质子和中子引起的单粒子效应等效关系,实验中采用金箔散射法降低了质子束流强度,并利用热释光剂量计(TLD)进行质子注量的监测,采用新研制的存储器长线实时监测系统,进行了64K位至4M位的SRAM器件单粒子效应实验,确定了两种粒子引起单粒子效应等效关系。 相似文献
72.
本文对弹药内弹道性能检验的传统方法存在的问题进行了分析,提出了一种新的检验方法,重点对新的检验方法的数学模型的建立过程进行了论述。并对数学模型的精度进行了分析、检验和验证。 相似文献
73.
Joo-Wan Kim Byung Sung Kim Sangwook Nam Choong Woong Lee 《Antennas and Propagation, IEEE Transactions on》1996,44(7):996-999
To specify manufacturing tolerances of a reflector antenna, various errors such as random surface errors and misalignment errors must be considered at one time because superposition of the effects of those errors may not hold. Based on the Rahmat-Samii's formulation (1983), a method for computing efficiently the average power pattern of a reflector antenna with those errors is presented. Simulation results show that superposition of the effects of errors does not generally hold and demonstrate how those errors degrade the peak-gain and sidelobe levels 相似文献
74.
Transient hot-electron effect and its impact on circuit reliability are investigated. The rate of device decay is monitored as a function of the gate pulse transient period. Simulation results reveal that excess charges during a fast turn off time may cause an increase in the maximum substrate current. This, along with our experimental data, identifies that transient excess carrier may cause the enhancement of device degradation under certain stress conditions. The enhancement factor of the degradation is a function of the gate pulse transient time. Correlation between the analysis based upon AC/DC measurement and calculations based upon transient simulation are shown in the paper. Better agreement with experimental data is obtained by using the transient analysis and on chip test/stress structures. The correlation between AC and DC stress data is also shown based on the impact ionization model. A hot-electron design guideline is proposed based on the circuit reliability analysis. This guideline can help improve the circuit reliability without adversely effecting the circuit performance. 相似文献
75.
76.
Kim S. Jeong S. Lee Y.T. Kim D.-H. Lim J.-S. Seo K.-S. Nam S. 《Electronics letters》2002,38(13):622-623
A new ultra-wideband, low-loss and small-size coplanar waveguide (CPW) to coplanar strip (CPS) transition which can be used from DC to 110 GHz is presented. The proposed transition connects CPW with CPS by the reformed air-bridge. Two ground planes of CPW are tied at their ends by a line and the centre of the line is connected to the ground strip of CPS by another line. Owing to the symmetry of the proposed structure, the currents of two ground planes of CPW are combined with the same phase and transferred to the ground strip of CPS. With height of 3 μm, the signal line of CPW passes over two connecting lines and is connected to the signal strip of CPS. For the back-to-back transition structure, insertion loss <1 dB and return loss >15 dB are obtained from 0.5 to 110 GHz 相似文献
77.
Thi Thi Nge Makiko Yamaguchi Naruhito Hori Akio Takemura Hirokuni Ono 《应用聚合物科学杂志》2002,83(5):1025-1035
Polyelectrolyte complex based on chitosan and acrylic acid monomer by photoinitiated free‐radical polymerization in the absence of crosslinker showed a large transition in swelling in response to changes in pH of surrounding medium. Their ability to swell arises from polyelectrolyte interactions and molecular structure of the complex. The main properties of interest that related to the molecular structure, swelling volumes, glass transition temperature, and elastic modulus of the complex were investigated. The effect of water content, the only variable in the sample component, played an important role in molecular structure of the complex and as a consequence, the extent of intermolecular linkage, especially amide bonds which in turn governed the degree of swelling of the polyelectrolyte complex in this study. The decreased degree of swelling and higher temperature shift of glass transition temperature was found with increased water content, whereas increased modulus of elasticity of dry complex was found in lower water content of synthesis component. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1025–1035, 2002 相似文献
78.
79.
Young Nam Chun Jen-Shih Chang Alexander A. Berezin J. Mizeraczyk 《Dielectrics and Electrical Insulation, IEEE Transactions on》2007,14(1):119-124
Numerical modelling of the flow velocity fields for the near corona wire electrohydrodynamic (EHD) flow was conducted. Solutions of the steady, two-dimensional momentum equations have been computed for a wire-plate type electrostatic precipitator (ESP). The equations were solved in the conservative finite-difference form on a fine uniform rectilinear grid of sufficient resolution to accurately capture the momentum boundary layers. The numerical procedure for the differential equations was used by SIMPLEST algorithm. The CFD code coupled with Poisson's electric field, ion transport equations and the momentum equation with electric body force, was used for the numerical simulation with the Chen-Kim k-epsiv turbulent model. The numerical results show that EHD secondary flow was clearly visible in the downstream regions of the corona wire despite the low Reynolds number for the electrode (Re cw=12.4). Secondary flow vortices caused by the EHD increases with increasing discharge current or EHD number, hence pressure drop of ESP increases 相似文献
80.