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排序方式: 共有1146条查询结果,搜索用时 15 毫秒
91.
Murat Manguoglu Ahmed H. Sameh Tayfun E. Tezduyar Sunil Sathe 《Computational Mechanics》2008,43(1):73-80
We present an effective preconditioning technique for solving the nonsymmetric linear systems encountered in computation of
incompressible flows in long domains. The application category we focus on is arterial fluid mechanics. These linear systems
are solved using a nested iterative scheme with an outer Richardson scheme and an inner iteration that is handled via a Krylov
subspace method. Test computations that demonstrate the robustness of our nested scheme are presented. 相似文献
92.
In this article we propose a multiple-output parity bit signature generation method for exhaustive testing of VLSI circuits. Given a multiple-output combinational circuit, a parity bit signature is generated by first EXORing all the outputs to produce a new output function and then feeding this resulting function to a single-output parity bit signature generator. The method preserves all the desirable properties of the conventional single-output circuits response analyzers and can be readily implemented using the current VLSI technology. 相似文献
93.
The loss of zero-voltage-switching (ZVS) of active switches has been a serious limitation of full-bridge (FBZVS) converters.
Many techniques have been proposed in the past to extend the range of ZVS operation over the wider and also the full range
of operation. However, in these techniques ZVS is achieved at the expense of additional conduction loss in active switches
and losses in the auxiliary components. In this paper, the analysis for the additional losses in various full-range FBZVS
DC-DC converters and their comparative evaluation is reported. Closed form expressions are derived for average value of device
currents and losses. The loss curves for various topologies are plotted and compared. The analytical results are found to
be consistent with the experimental efficiency tests performed on 500 W, 100 kHz prototype. It is concluded that a recently
proposed new topology has the least penalty of additional losses. 相似文献
94.
Harinder Singh Oberoi Sunil Bansal & Gurpreet Singh Dhillon 《International Journal of Food Science & Technology》2008,43(8):1499-1504
Among the five Kluyveromyces marxianus strains tested for β-galactosidase production, K. marxianus NCIM 3465 showed maximum enzyme activity of 1.62 IU mg−1 dry weight. Different levels (5–25%, w/v) of dried cauliflower waste were incorporated into whey to evaluate the effect of its supplementation on enzyme production. Although a marginal increase in enzyme production was seen by incorporating 5% and 10% cauliflower waste in whey, nearly 15% increase in β-galactosidase production was observed when cauliflower waste level was increased to 20% compared with whey alone. Supplementing whey with 20% cauliflower waste also decreased the production time. Lactose concentration in whey, mainly responsible for increasing the biological oxygen demand load of the effluent water, decreased from 4.2% to nearly 0% at 24 h. Thus, this study demonstrated that both these by-products/residues could be effectively used for β-galactosidase production at commercial scale. 相似文献
95.
Niranjan Mahendra Singh Jha Sunil 《The International Journal of Advanced Manufacturing Technology》2015,80(9-12):1895-1902
The International Journal of Advanced Manufacturing Technology - Magnetorheological (MR) finishing is a smart finishing processes applied to a variety of applications. In the present work, an... 相似文献
96.
The dry hot syngas cleaning process appears to be potentially more efficient and cleaner than the proven wet cleaning or semi-wet cleaning processes but it is still far from commercialisation. There are several technological barriers responsible such as poor availability factor, degeneration of sorbent and several stages of separation. This paper summarises the reported current status of dry hot cleaning of syngas from coal gasification processes along with the shortcomings of reporting of dry hot syngas cleaning performance results. The paper also proposes and discusses a rational method of performance reporting, a novel pulse less filtration concept and a system to prevent failure of filter elements. 相似文献
97.
CO2 flooding, which is an efficient method of enhanced oil recovery, is a very complicated process involving phase behavior. To understand the performance of CO2 flooding and provide accurate data for designing reservoir development, a comprehensive investigation of the phase behavior of CO2 miscible flooding and an accurate compositional reservoir simulation needs to be conducted. In PVT modeling, an effective and more physically reasonable equation of state model was achieved and the feasibility of CO2 miscible flooding was determined by multiple contact minimum miscibility pressure (MCMMP) calculation. Furthermore, compositional reservoir simulation studies for predicting CO2 miscible performance were designed and constructed with core flooding data. By matching with laboratory core flooding data, we can estimate parameters with uncertainty. The objective of this study was to find a work flow for parameter estimation in CO2 miscible flooding process that can be used to design and optimize field CO2 miscible floods. 相似文献
98.
In this paper we report successful simple synthesis of unique elastic polyesters by carrying out catalyst-free polyesterification of multifunctional non-toxic monomers: 1,8-octanediol (OD), citric acid (CA) and sebacic acid (SA). The chemical, physical, and surface chemical properties of the resulting copolyester polyoctanediol citrate/sebacate [p(OCS)] have been investigated. This new material was characterized by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-ToF-MS), nuclear magnetic resonance spectroscopy (NMR), thermal analysis (TA), mechanical tests, photo-acoustic Fourier-transform infrared spectroscopy (PA-FTIR), X-ray photoelectron spectroscopy (XPS) and swelling experiments. We demonstrate that the chemical structure, morphology, physical integrity and surface chemistry of the synthesized co-polymer can be controlled by simply varying the initial acid concentration (CA/SA) in the pre-polymer. This novel p(OCS) polymer exhibits versatility in mechanical properties, hydration and hydrolytic degradation as determined by the chemical structure of the polyester elastomer. 相似文献
99.
100.