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991.
The modular algebraic structure of the residue number systems (RNS) leads to modularity and parallelism in the hardware implementation for the RNS-based arithmetic processor [1], [2]. Both modularity and parallelism are essential to fully utilize the very-large-scale integrated (VLSI) technology [3]. In this work, a superfast algorithm for correcting single residue errors in the RNS is developed with a slight increase in redundancy. Based on this algorithm and another recently proposed fast algorithm, two architectures are designed for their hardware implementation. The hardware complexity for this superfast algorithm isO(k) while the hardware complexity for previously known algorithms isO(k 2). The performance of this new technique is compared to the previously known techniques in terms of computational speed and other criteria.  相似文献   
992.
Several statistical design methods that have been developed to minimize the effects of IC manufacturing process disturbances on circuit performance are reviewed. It is shown that statistical design problems can be expressed as optimization problems in which either the objective function or the constraint functions depend on expectations of random variables. The effectiveness of the most recent such method, the boundary integral method is illustrated with several circuit design examples  相似文献   
993.
Experimental viscosities were measured by Schott Gerate viscometer at 30 °C for polystyrene–chloroform and polycaprolactum–benzene systems. These data were analyzed by a newly developed analytical method to calculate intrinsic viscosity and viscosity constants. The analytical method was compared with the graphical as well as the least squares methods and the new analytical method is better than the graphical method because it avoids personal errors that might arise in reading the intercept and slope values from the reduced viscosity versus concentration plots. Furthermore, the analytical method is as effective as the least squares method, but provides better insights while choosing the experimental viscosity values. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 283–290, 2002  相似文献   
994.
995.
This paper presents a new test data-compression scheme that is a hybrid approach between external testing and built-in self-test (BIST). The proposed approach is based on weighted pseudorandom testing and uses a novel approach for compressing and storing the weight sets. Three levels of compression are used to greatly reduce test costs. Experimental results show that the proposed scheme reduces tester storage requirements and tester bandwidth requirements by orders of magnitude compared to conventional external testing, but requires much less area overhead than a full BIST implementation providing the same fault coverage. No test points or any modifications are made to the function logic. The paper describes the proposed hybrid BIST architecture as well as two different ways of storing the weight sets, which are an integral part of this scheme.  相似文献   
996.
N-(2-pyridyl) pyrrole was synthesized and polymerised to make a conducting polymer suitable for sensing volatile chemical species. The high frequency electrical responses of this material to methanol, acetone and ethyl acetate vapours were investigated. The results demonstrate a multiparametric technique for identification of volatile chemicals, on the basis of the changes in several electrical characteristics induced by the molecular interaction of adsorbed species on the conducting polymer.  相似文献   
997.
A sensitive gas chromatographic (GC) method with electron-capture detection (ECD) has been developed to quantitate indomethacin (IND) in plasma, urine, amniotic, and tracheal fluids obtained from the pregnant sheep model. IND and the internal standard, alpha-methylindomethacin (alpha-Me-IND) are extracted by a simple liquid-liquid extraction procedure using ethyl acetate and derivatized with N-methyl-N-(tert.-butyldimethyl-silyl)trifluoroacetamide (MTBSTFA) at 60 degrees C for 50 min. The limit of quantitation (LOQ) is 1 ng/ml with a C.V. < 10% and signal-to-noise ratio > 10. Recoveries from all fluids were greater than 80%. Calibration curves were linear over the range of 1-32 ng/ml with a coefficient of determination (r2) > 0.999. Inter- and intra-day coefficients of variation were < 10% at concentrations of 2-32 ng/ml, and < 20% at the LOQ. Applicability of the developed method is demonstrated for a pharmacokinetic study of IND samples collected following long-term infusion of IND in a chronically instrumented ovine fetus.  相似文献   
998.
This article discusses the phenomenon of inverse relaxation in some textile fibers, namely cotton, ramie, wool, polyester, and viscose. If anextended viscoelastic specimen is allowed to recover a part of the deformation given to it, such that its tension has not become zero, the stress in it tends to increase. This phenomenon is termed as “inverse relaxation.” This property is measured in terms of an index referred to as the inverse relaxation index. The values of this index at various extension and retraction levels for the above materials are presented and discussed in this article.  相似文献   
999.
1000.
Heat transfer associated with film boiling in forced-convection boundary-layer flow over a flat plate whose temperature is an arbitrary function of time is studied analytically using boundary-layer theory. The governing equations are solved by a perturbation technique. The effect on heat transfer of varying the fluid properties is discussed.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 19, No. 3, pp. 453–463, September, 1970.  相似文献   
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