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991.
Yoon-Hwa Choi 《Journal of Electronic Testing》1990,1(3):201-211
This article presents a distributed fault-diagnosis algorithm for identifying faulty and fault-free units (processors, PEs, cells) in homogeneous systems. It is based on local comparison among units in a system and dissemination of the test results. Each unit performs comparison with its neighbors by using its own comparator. Unlike other approaches, the algorithm does not assume that diagnostic circuits are fault free. The algorithm is simple enough to be realized with small circuit overhead. The results are especially useful in locating faulty units in processor arrays implemented on a single chip or wafer. Computer simulation has shown that even for low unit yields, extremely high performance (fault coverage) can be obtained by adjusting algorithm parameters. 相似文献
992.
993.
K. Y. Choi 《Polymer Engineering and Science》1986,26(14):975-981
The steady state structure of non-isothermal free radical solution polymerization in a continuous stirred tank reactor is analyzed. With mean residence time as a bifurcation parameter, five regions of steady states are identified. The effect of reactor operating conditions on the structure and the stability of steady state is discussed. 相似文献
994.
Ho-Young Cha Y. C. Choi R. M. Thompson V. Kaper J. R. Shealy L. F. Eastman M. G. Spencer 《Journal of Electronic Materials》2004,33(8):908-911
The SiC metal-semiconductor field-effect transistors (MESFETs) have been reported to have current instability and strong dispersion
caused by trapping phenomena at the surface and in the substrate, which degrade direct-current (DC) and radio-frequency (RF)
performance. This paper illustrates the change in electrical characteristics of SiC MESFETs after Si3N4 passivation. Because of a reduction of surface trapping effects, Si3N4 passivation can diminish current collapse under pulsed DC conditions, increasing the RF power performance. The reduction
of surface trapping effects is verified by the change in the ratio of the drain current to the gate current under pinch-off
conditions. 相似文献
995.
The performance of a virtual time idle-signal casting multiple access with collision detection (ICMA/CD) protocol is analysed under the infinite population model. Compared to the existing nonpersistent and 1-persistent schemes, the virtual time protocol exhibits high throughput and lower packet failure probability in mobile radio networks.<> 相似文献
996.
997.
Wan Choi Chaehag Yi Jin Young Kim Dong In Kim 《Communications, IEEE Transactions on》2004,52(11):1851-1856
A new base station receiver is proposed and analyzed for a code-division multiple-access (CDMA) cellular system. The proposed receiver can achieve remarkable diversity gain by increasing diversity order with reasonable cost and complexity. From the numerical results, it is confirmed that the proposed receiver structure can be a practical solution for enhancing reverse-link capacity and improving performance in CDMA cellular system operations. The result in the letter can find its applications to legacy IS-95/cdma2000 1x base stations with simple modifications. 相似文献
998.
Jinwoo Choi Dong Gun Kam Daehyun Chung Srinivasan K. Govind V. Joungho Kim Swaminathan M. 《Advanced Packaging, IEEE Transactions on》2007,30(2):180-190
This paper presents near-field (NF) and far-field (FF) analysis of alternating impedance electromagnetic bandgap (AI-EBG) structure in packages and boards. Three test vehicles have been designed and fabricated for NF and FF measurements. Simulation results using a full-wave solver (SONNET) have been compared with measurement results. This paper investigates the radiation due to return current on different reference planes. The analysis results from simulations and measurements provide important guidelines for design of the AI-EBG structure based power distribution network for noise isolation and suppression in mixed-signal systems 相似文献
999.
This study presents a good example for the tertiary treatment of biologically treated piggery wastewater using vibratory shear enhanced RO membrane (VSEP RO). Through a simple process combination, utilizing Bioceramic SBR(BCS) and VSEP RO, at Gimhae plant livestock wastewater is treated excellently to meet the strict effluent standards. Application of RO membrane directly to the biologically treated effluent has been successful without any pretreatment to reduce high suspended solids. The combination of VESP UF followed by RO filtration processes produced a higher recovery rate in the 3-week pilot test. 相似文献
1000.
Hyoung‐Woo Kim Hongju Kim Soonman Kwon Joon‐Young Choi 《IEEJ Transactions on Electrical and Electronic Engineering》2016,11(5):633-639
A robust backstepping controller with nonlinear damping is designed for the grid‐side converter (GSC) of a grid‐connected doubly fed induction generator (DFIG) in wind energy conversion systems (WECSs). The designed controller achieves the exponential ultimate boundedness of both the DC‐link voltage and GSC current errors with an arbitrarily fast decay rate and an arbitrarily small bound in the presence of both model uncertainties and time‐varying external disturbances. A desirable feature that distinguishes the proposed controller from other existing controllers is that the control input of GSC is constructed only by the static feedback of the measurable states. As a result, the control input becomes smooth and easy to implement without requiring differentiation or switching operations. The exponential boundedness and performance of the designed controller are demonstrated by simulation using a 1.5‐MW DFIG‐based WECS model built in MATLAB/SimPowerSystems and compared with a standard proportional‐integral controller. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献