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991.
Mike Tien-Chien Lee Yu-Chin Hsu Ben Chen Masahiro Fujita 《Design Automation for Embedded Systems》1997,2(3-4):319-338
ATM switch, the core technology of an ATM networking system, is one of the major products in Fujitsu telecommunication business. However, current gate–level design methodology can no longer satisfy its stringent time–to–market requirement. It becomes necessary to exploit high–level methodology to specify and synthesize the design at an abstraction level higher than logic gates. This paper presents our prototyping experience on domain–specific high–level modeling and synthesis for Fujitsu ATM switch design. We propose a high–level design methodology using VHDL, where ATM switch architectural features are considered during behavior modeling, and a high–level synthesis compiler, MEBS, is prototyped to synthesize the behavior model down to a gate–level implementation. Since the specific ATM switch architecture is incorporated into both modeling and synthesis phases, a high–quality design is efficiently derived. The synthesis results shows that given the design constraints, the proposed high–level design methodology can produce a gate–level implementation by MEBS with about 15 percent area reduction in shorter design cycle when compared with manual design. 相似文献
992.
Unlu M.S. Strite S. Won T. Adomi K. Chen J. Mohammad S.N. Biswas D. Morkoc H. 《Electronics letters》1989,25(20):1359-1360
Reports the nearly ideal electrical characteristics of p-Ge/N-GaAs heterojunction diodes grown by molecular beam epitaxy. The temperature and device size dependencies of the current-voltage characteristics have been investigated. At room temperature, unity ideality factor has been demonstrated over almost six decades of current.<> 相似文献
993.
提出一种新型基于源极跟随器的零极点型滤波器。提出的单支路全差分的双二阶单元采用两个前馈电容综合复数零点,用于实现连续时间零极点型滤波器。源极跟随器在电压域直接处理信号使得该双二阶单元以低功耗实现高线性度。利用CMOS0.18μm工艺级联实现了一个4阶切比雪夫Ⅱ型全差分低通滤波器。测试结果表明,滤波器带宽为2.75MHz,实现了带外下陷特性。在2V电源电压下,消耗电流为1.5mA,测得带内IIP3为5dBm。在三次谐波失真(HD3)为-46.3dB条件下滤波器的动态范围为65dB。 相似文献
994.
采用数字化设计技术不仅有利于提高大型装备的设计质量,而且能够缩短研制时间和降低研制成本,因此具有十分明显的学术价值和应用价值。本文以航空发动机中的润滑与冷却工作系统为研究对象,建立了针对这一系统的数字化设计平台,并对其中的关键技术问题进行了研究和分析。本文的研究方法和成果亦为类似的其它装备系统的数字化设计工作提供了参考依据。 相似文献
995.
Qiansheng Cheng Rong Chen Ta-Hsin Li 《Geoscience and Remote Sensing, IEEE Transactions on》1996,34(2):377-384
The problem of simultaneous wavelet estimation and deconvolution is investigated with a Bayesian approach under the assumption that the reflectivity obeys a Bernoulli-Gaussian distribution. Unknown quantities, including the seismic wavelet, the reflection sequence, and the statistical parameters of reflection sequence and noise are all treated as realizations of random variables endowed with suitable prior distributions. Instead of deterministic procedures that can be quite computationally burdensome, a simple Monte Carlo method, called Gibbs sampler, is employed to produce random samples iteratively from the joint posterior distribution of the unknowns. Modifications are made in the Gibbs sampler to overcome the ambiguity problems inherent in seismic deconvolution. Simple averages of the random samples are used to approximate the minimum mean-squared error (MMSE) estimates of the unknowns. Numerical examples are given to demonstrate the performance of the method 相似文献
996.
Fractal feature analysis and classification in medical imaging 总被引:14,自引:0,他引:14
Following B.B. Mandelbrot's fractal theory (1982), it was found that the fractal dimension could be obtained in medical images by the concept of fractional Brownian motion. An estimation concept for determination of the fractal dimension based upon the concept of fractional Brownian motion is discussed. Two applications are found: (1) classification; (2) edge enhancement and detection. For the purpose of classification, a normalized fractional Brownian motion feature vector is defined from this estimation concept. It represented the normalized average absolute intensity difference of pixel pairs on a surface of different scales. The feature vector uses relatively few data items to represent the statistical characteristics of the medial image surface and is invariant to linear intensity transformation. For edge enhancement and detection application, a transformed image is obtained by calculating the fractal dimension of each pixel over the whole medical image. The fractal dimension value of each pixel is obtained by calculating the fractal dimension of 7x7 pixel block centered on this pixel. 相似文献
997.
光子晶体光纤(PCFs)的应用在很多方面改善了传统光纤传感器的性能.基于 PCFs的光纤传感器对应力和液体折射率具有较高的传感精度以及更好的温度特性,并且可以灵活引入各种耦合结构单元组成干涉仪,介绍了基于光纤布拉格光栅(FBG)、长周期光栅(LPG)和干涉仪的PCFs传感器的基本构造、工作原理和最新的研究进展. 相似文献
998.
Maoxiong Zhao Mu Ku Chen Ze-Peng Zhuang Yiwen Zhang Ang Chen Qinmiao Chen Wenzhe Liu Jiajun Wang Ze-Ming Chen Bo Wang Xiaohan Liu Haiwei Yin Shumin Xiao Lei Shi Jian-Wen Dong Jian Zi Din Ping Tsai 《光:科学与应用(英文版)》2021,10(4):551-561
Metalenses have emerged as a new optical element or system in recent years, showing superior performance and abundant applications. However, the phase distribut... 相似文献
999.
Sensors: 6‐Mercaptopurine‐Induced Fluorescence Quenching of Monolayer MoS2 Nanodots: Applications to Glutathione Sensing,Cellular Imaging,and Glutathione‐Stimulated Drug Delivery (Adv. Funct. Mater. 41/2017) 下载免费PDF全文
1000.