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961.
The probability of capture under a model (for a land mobile radio direct sequence spread spectrum system) based on the ratio of the largest received power to the sum of interference powers is examined in the limit of a large number of transmitting stations. It is shown in great generality that the limit depends only on the capture ratio threshold and the roll-off exponent of the distribution of power received from a typical station. This exponent is insensitive to many typical channel effects such as Rician or Rayleigh fading and log-normal shadowing. The model is suitable for large systems with noncoherently combined interference 相似文献
962.
Experiments are carried out on a R11 vapour jet refrigeration system (VJRS) to study the influence of ejector configuration and operating conditions on the performance. Eight ejector configurations, formed out of five nozzles and seven diffusers are investigated. The influence of boiler temperature, which represents the solar energy collection temperature, and that of evaporating temperature, which denotes the cooling load temperature, are studied. Overall COPs in the range of 0.08-0.33 and evaporating temperatures in the range of −3–18°C are obtained for boiler temperatures from 75 to 85°C. Ejector configuration has significant influence in deciding the operating range. 相似文献
963.
K S Raju K N Krishna Jayakumari Issac M A Ittyachen 《Bulletin of Materials Science》1994,17(7):1447-1455
Sparingly soluble neodymium copper oxalate (NCO) single crystals were grown by gel method, by the diffusion of a mixture of
neodymium nitrate and cupric nitrate into the set gel containing oxalic acid. Tabular crystal, revealing well-defined dissolution
figures has been recorded. X-ray diffraction studies of the powdered sample reveal that NCO is crystalline. Infrared absorption
spectrum confirmed the formation of oxalato complex with water of crystallization, while energy dispersive X-ray analysis
established the presence of neodymium dominant over copper in the sample. X-ray photoelectron spectroscopic studies established
the presence of Nd and Cu in oxide states besides (C2O4)2− oxalate group. The intensities of Nd (3d
5/2) and Cu (2p
3/2) peaks measured in terms of maximum photoelectron count rates also revealed the presence of Nd in predominance. The inductively
coupled plasma analysis supports the EDAX and XPS data by the estimation of neodymium percentage by weight to that of copper
present in the NCO sample. On the basis of these findings, an empirical structure for NCO has been proposed. The implications
are discussed. 相似文献
964.
Hari Krishna Garg 《Circuits, Systems, and Signal Processing》1996,15(3):415-435
In our recent work, we solved the word sequence length constraint problem associated with number theoretic transforms defined in finite integer rings. This is based on the American-Indian-Chinese extension of the Chinese remainder theorem. This work builds further on the results by extending them to the domain of integer polynomial rings. The theory of polynomial factorization and the resulting direct sum property are studied in depth. The emphasis is on the theory of computational algorithms for processing sequences defined in finite integer and complex integer rings. 相似文献
965.
B Saha B Jana J S Yadav Ch Rama Krishna YVH Rao B Gupta 《Bulletin of Materials Science》1996,19(4):661-669
Titanium alloys, because of their excellent specific strength/density ratio result in significant weight reduction in airborne
vehicles thus improving their performance and fuel efficiency. In addition, excellent corrosion resistance, high fracture
toughness, creep strength up to ∼ 600°C make them a wanted material for aeroengine applications. Though a number of alloys
are in use, Ti-8Al-1Mo-1V alloy, due to its advantageous characteristics has been selected for HP compressor blades for Adour
engine (JAGUAR Aircraft) applications. Optimization of chemical composition, forging technology and heat treatment were the
main objectives to obtain best combination of properties for the end use. The alloy has been successfully evaluated in accordance
with mandatory airworthiness requirements.
Paper presented at the poster session of MRSI AGM VI, Kharagpur, 1995 相似文献
966.
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
967.
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
968.
Udaya S. Toti Krishna S. Amur Mahadevappa Y. Kariduraganavar Lata S. Manjeshwar Mrityunjaya I. Aralaguppi Tejraj M. Aminabhavi 《应用聚合物科学杂志》2002,83(2):283-290
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
969.
S Krishna 《Canadian Metallurgical Quarterly》1997,315(7110):730-732
970.
Jas A. Krishna C.V. Touba N.A. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2004,12(12):1277-1283
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