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991.
992.
一种基于事务的SoC功能验证方法 总被引:1,自引:0,他引:1
本文介绍了基于事务的SoC验证方法,详细说明了事务、事务处理器的概念和事务级验证平台的功能结构.Synopsys公司的RVM验证方法学是当前比较流行的基于事务的SoC验证方法,文中详细介绍了RVM验证平台的层次结构.并且以一个UART模块的功能验证为例,描述了如何利用RVM验证方法学搭建一个高效的可重用的验证平台. 相似文献
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This paper presents a large anisotropic damage theory of continuum damage mechanics. It is developed via a new hypothesis of incremental complementary elastic energy equivalence. This hypothesis is more versatile and accurate if compared to the original hypothesis of total complementary energy equivalence. To model the large damage, we assumed that it occurs as a series of incremental small damage. An expression for the damage effect tensor M(D) for large damage is derived. It is shown that when the damage is small, that is, D
i1, the proposed large damage theory reduces to the small damage model of Chow and Wang [1]. To demonstrate this large damage theory, it is applied to model the following cases: (a) uniaxial tension, (b) pure torsion and (c) elastic perfectly-plastic material behavior. In all three cases, the results clearly show that when the damage is small, Chow and Wang's model is recovered. However, for large damage, there are significant differences in predictions. Since this large damage theory is formulated on the basis of the incremental complementary energy, it is applicable to a wider range of problems. 相似文献
996.
Yong YK Zhang Z 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1994,41(5):685-693
Finite element matrix equations, derived from two-dimensional piezoelectric high frequency plate theory are solved to study the vibrational behavior of the third overtone of thickness shear in square and circular SC-cut quartz resonators. The mass-loading and electric effects of electrodes are included. A perturbation method which reduces the memory requirements and computational time significantly is employed to calculate the piezoelectric resonant frequencies. A new storage scheme is introduced which reduces memory requirements for mass matrix by about 90% over that of the envelope storage scheme. Substructure techniques are used in eigenvalue calculation to save storage. Resonant frequency and the mode shapes of the harmonic third overtone thickness shear vibrations for square and circular plates are calculated. A predominant third overtone thickness shear displacement, coupled with the third overtone of thickness stretch and thickness twist, is observed. Weak coupling between the third order thickness shear displacement and the zeroth-, first-, and second-order displacements is noted. The magnitudes of the lower order displacements are found to be about two orders smaller than that of the third overtone thickness shear displacement. 相似文献
997.
Seok Woo Choi Dong Yong Kim Hyong Kap Kim 《Analog Integrated Circuits and Signal Processing》1994,6(2):95-103
A modified low-pass filter functions are proposed. A modified inverse Chebyshev function possesses progressively diminishing ripples in the stopband whereas the modified Chebyshev function exhibits ripples diminishing toward = 0 in the passband.Both are realizable in the doubly-terminated ladder structures for the ordern even or odd, thus lending themselves amenable to high-quality activeRC or switched capacitor filters through the simulation techniques. 相似文献
998.
Hwan Seong Moon Jae Suk Lee Sung Wook Han Jong Wan Park Jae Hak Lee Seung Kee Yang Hyung Ho Park 《Journal of Materials Science》1994,29(6):1545-1548
Tantalum oxide film formation by plasma-enhanced chemical vapour deposition (PECVD) using TaCl5 as a source material was examined. The effects of deposition temperature on the formation, structure and electric properties of the Ta2O5 film were investigated for Al/Ta2O5/ p-Si (MTS) capacitors. The deposition rate and refractive index increased with increasing deposition temperature. It was found that the structure of Ta2O5 deposited by PECVD was amorphous as-deposited. However, crystalline -Ta2O5 of hexagonal structure was formed by a 700 °C, 1 h heat treatment in argon. Capacitance and relative dielectric constant of the PECVD Ta2O5 were found to be 2.54 fF m–2 and 23.5, respectively. The PECVD films obtained in this study have higher dielectric constants and remarkably better general film characteristics than those obtained by other deposition methods. 相似文献
999.
Summary A poly(2,6-dimethyl-1,4-phenylene oxide) (PPO, 1) macroinitiator having carbonylcaprolactam groups was prepared through metalation of methyl group of PPO and subsequent modification to introduce carboxyl group, acid chloride group, and finally carbonylcaprolactam group. Anionic ring opening copolymerization of -caprolactam took place onto the macroinitiator to give a graft copolymer of PPO and Nylon 6. The structure of intermediate materials and the graft copolymer were characterized by 1H NMR, 13C NMR, and IR spectroscopy. Glass transition temperatures and melting temperatures of these materials are also reported. It is found that the copolymer has a microphase-separated morphology even with segment molecular weight as low as 3000. 相似文献
1000.