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961.
E. M. Baskin 《Microelectronics Reliability》2002,42(12):1967-1974
Empirical lifetime distributions sometimes have a bathtub-shaped failure rate. This paper deals with some models having a bathtub-shaped failure rate. The root-mean-square criterion is proposed for selection of the best model. Besides two criteria of optimum burn-in time are proposed. The comparison of some models with the general law of reliability is given to determine a burn-in time in a number of examples. 相似文献
962.
A mixed mode digital/analog special purpose VLSI hardware implementation of an associative memory with neural architecture is presented. The memory concept is based on a matrix architecture with binary storage elements holding the connection weights. To enhance the processing speed analog circuit techniques are applied to implement the algorithm for the association. To keep the memory density as high as possible two design strategies are considered. First, the number of transistors per storage element is kept to a minimum. In this paper a circuit technique that uses a single 6-transistor cell for weight storage and analog signal processing is proposed. Second, the device precision has been chosen to a moderate level to save area as much as possible. Since device mismatch limits the performance of analog circuits, the impact of device precision on the circuit performance is explicitly discussed. It is shown that the device precision limits the number of rows activated in parallel. Since the input vector as well as the output vector are considered to be sparsely coded it is concluded, that even for large matrices the proposed circuit technique is appropriate and ultra large scale integration with a large number of connection weights is feasible. 相似文献
963.
O. Perat J. M. Dorkel E. Scheid P. Temple Boyer Y. S. Chung A. Peyre-Lavigne M. Zecri P. Tounsi 《Microelectronics Reliability》2002,42(7):1053-1058
Reliability of thermomechanical simulations is critically linked to the accuracy of the mechanical properties that govern the behaviour of structure, like Young's modulus (E) and coefficient of thermal expansion (CTE). For many cases, the values found in literatures are dealing with bulk properties without detailed information on temperature effects. To address such issues, it is necessary to measure the materials parameters as a function of temperature. The measurement of CTE is usually accomplished by evaluating the thermal deflections of a subjected material layer deposited on a substrate, providing that E is known at a specific temperature of experiment. A bilayer method, based on theory of elasticity, is proposed to determine both E and CTE for a given temperature with a good resolution. This paper presents the theoretical analysis, the design and process of the microsystem test structures, and the main calculation results. 相似文献
964.
对于今天的织物,易护理性是一项基本要求。然而,理想的易护理效果不可能仅通过Tencel纤维本身的性能来获得,合适的织物组织结构、恰当的前处理,以及最佳的高级整理加工可以提高Tencel织物的易护理性能,并超过其他纤维素纤维。关于织物组织结构的影响已经在其他杂志上有过讨论。本文将说明如何采用不同的前处理、后整理加工,获得高档最终产品的方法。 相似文献
965.
966.
G.D. Wignall R.W. Hendricks W.C. Koehler J.S. Lin M.P. Wai E.L. Thomas R.S. Stein 《Polymer》1981,22(7):886-889
A series of small angle neutron scattering measurements on blends of normal polystyrene (PSH) and labelled (deuterated) polystyrene (PSD) have been made with concentrations of PSD from 5 to 50 mol %. It is shown that the single chain form factor of the polymer in bulk can be obtained from a single concentration measurement for any concentration of labelled molecules, providing the molecular weights of the parent and labelled molecules are the same and the molecular weight distributions are narrow. 相似文献
967.
M. D. Korostash 《Drying Technology》1985,3(4):603-611
The paper presents the results of research in the convection drying of unidirectional glass fibre bobbins on the basis of which the relations are suggested required to calculate the process of drying in the design of drying equipment. 相似文献
968.
Field surveys of a series of conjugated diunsaturated straight-chain primary alcohols, acetates, and aldehydes (dienes), including the 3,5-dode-cadienyl, 8,10-dodecadienyl, 3,5-tetradecadienyl, 8,10-tetradecadienyl, 9,11-tetradecadienyl, and 10,12-tetradecadienyl primary alcohols, acetates, and most aldehydes, and the related monounsaturated straight-chain primary alcohols, acetates, and aldehydes (monoenes), including the 3-dodecadienyl alcohol and acetates, attracted the following species from the title families. Diene attractants have been demonstrated for at least onePhyllonorycter sp.,Chionodes lugubrella (Fabr.),Leptostales ferruminaria (Zell.),Drepana bilineata (Pack.),Pyrausta fodinalis (Led.),Notocelia purpurissatana Heinr.,Phaneta alterana Heinr. Monoene attractants were demonstrated forHedya separatana (Kft.),Cydia fletcherana (Kft.),Barbara mappana Free.,Ancylis burgessiana (Zell.),Ancylis nubeculana Clem.,Evippe prunifoliella Cham.,Phlyctaenia coronata tertialis (Gn.), aChionodes sp., a Gelechiidae sp., and an unidentifiedPhyllonorycter sp. Replicated field experiments showed attraction-inhibition relationships for most species. Electroantennagram data are presented forLeptostales ferruminaria andDrepana bilineata. 相似文献
969.
Michael L. Mushet 《Information Systems Management》1991,8(3):21-26
For the past three decades, IS managers have been faced with the tasks of honing their craft, improving productivity, and serving as the keepers of information technology for the corporation. For the most part, they have done a commendable job. However, the rules of the game are changing. Old solutions are no longer extensible to current problems, and today's problems are unlike any faced in the past. This article takes a fresh look at what the top priorities for IS managers should be in the coming years. 相似文献
970.
Naphthalene-2,3-dicarboxaldehyde (NDA) has been investigated as a new derivatizing reagent for the electrochemical detection of tagged amino acids. Gradient elution allowed for the separation of 18 NDA-derivatized amino acids on an open tubular liquid chromatography column in less than 50 min. Gradient elution and electrochemical detection were found to be compatible. A detection limit of 36 amol was obtained for the asparagine-NDA derivative. The usefulness of this technique for quantitation was demonstrated by the analysis of the NDA-tagged hydrolysis products from bovine chymotrypsinogen. 相似文献