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61.
Functional verification is widely recognized as the bottleneck of the hardware design cycle. With the ever-growing demand for greater performance and faster time to market, coupled with the exponential growth in hardware size, verification has become increasingly difficult. Although formal methods such as model checking and theorem proving have resulted in noticeable progress, these approaches apply only to the verification of relatively small design blocks or to very focused verification goals. Current industry practice is to use separate, automatic, random stimuli generators for processor- and multiprocessor-level verification. The generated stimuli, usually in the form of test programs, trigger architecture and microarchitecture events defined by a verification plan. MAC-based algorithms are well suited for the test program generation domain because they postpone heuristic decisions until after consideration of all architectural and testing-knowledge constraints. Geneysys-Pro is currently the main test generation tool for functional verification of IBM processors, including several complex processors. We've found that the new language considerably reduces the effort needed to define and maintain knowledge specific to an implementation and verification plan.  相似文献   
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Thapsigargin (TG), a plant-derived sesquiterpene lactone, inhibits several isoforms of both the sarcoplasmic and endoplasmic reticulum Ca2+-ATPases. Thus, intracellular Ca2+ stores found in the endoplasmic reticulum can be released by this compound. The mammalian sperm acrosome reaction (AR) depends on influx of extracellular Ca2+. However, few reports have presented evidence for the involvement of putative Ca2+ stores and intracellular Ca2+ mobilization in the AR. Thus, we designed experiments to evaluate the effect of TG on the hamster sperm AR. Thapsigargin stimulated-in a dose-dependent manner-the AR of spermatozoa previously capacitated for at least 3 hr, not affecting sperm motility. A maximal stimulatory effect was apparent 3 min after addition of TG to spermatozoa previously capacitated for 4 hr and was dependent on external Ca2+ since ethyleneglycol-bis-(b-amino-ethyl ether) N,N'-tetra-acetic acid added 1 min before TG completely inhibited AR stimulation. The Ca2+ channel blockers diltiazem and nifedipine also abolished the TG-stimulatory effect when added to capacitated spermatozoa 10 min before the inhibitor. In addition, the trypsin inhibitors p-nitrophenyl-p'-guanidine-benzoate hydrochloride and benzamidine added to the sperm suspensions 10 min before TG inhibited by 70-80% the TG-induced AR. These results indicate that putative Ca2+ stores release may be involved in stimulation of extracellular Ca2+ influx required for the occurrence of the AR. In addition, a sperm trypsin-like protease may be part of the mechanism by which TG induces the hamster sperm AR.  相似文献   
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A three‐dimensional computational fluid dynamics code was used to analyse the performance of 550MW pulverized coal combustion opposite a wall‐fired boiler (of IEC) at different operation modes. The main objective of this study was to prove that connecting plant measurements with three‐dimensional furnace modelling is a cost‐effective method for design, optimization and problem solving in power plant operation. Heat flux results from calculations were compared with measurements in the boiler and showed good agreement. Consequently, the code was used to study hydrodynamic aspects of air–flue gases mixing in the upper part of the boiler. It was demonstrated that effective mixing between flue gases and overfire air is of essential importance for CO reburning. From our complementary experimental‐numerical effort, IEC considers a possibility to improve the boiler performance by replacing the existing OFA nozzles by those with higher penetration depth of the air jets, with the aim to ensure proper mixing to achieve better CO reburning. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
65.
Tissue cultures find increasingly widespread applications for cloning of many plants. Commercial propagation by tissue cultures is limited to ornamental plants, because the cost of skilled labor required cannot compete with conventional propagation methods. To cut down the cost, some automation is essential. A cost-effective approach is to chop the plantlets into segments on a conveying production line while using machine vision for identifying and locating the number and positions of propagation organs in images of the plantlet segments. Plantlet segments without propagation organs will be rejected, while segments with viable buds will be selected for subculturing. To this end, a machine-vision-controlled automatic subculturing system for potato tissue cultures is proposed as a simpler and more cost-effective solution than the popular trend of imitating the manual sub-culturing task by a robot. A simple and relatively fast image-processing algorithm particularly suitable for classification of potato tissue cultures, was developed. In lieu of the general Medial Axis Transform approach, this specialized algorithm takes advantage of the inherent difference between the geometrical shape and gray scale levels of the stems and the leaves as well as of the rather simple connectivity rules of attachment between them. The results indicate that machine inspection and classification of tissue culture plantlets is possible, but considerably more work needs to be done before this technique is fully developed for automating tissue culture processes.  相似文献   
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An impinging-stream reactor, developed and tested for calcination of phosphate with low organic matter content, has proven to be an efficient device for conducting this process. Modeling of the calcination process has been done along two lines. Considering a single particle and assuming that calcination rate is controlled by the heat transfer in the particle, resulted in a criterion for testing the effect of temperature on the enrichment of P205 and other phenomena. Performing a heat balance on the reactor and on the particle, and incorporating physical concepts, led to correlations with only one adjustable parameter for the conversion of carbonates as a function of the operating parameters. The major conclusion drawn from implementation of the model was that phosphate calcination is governed by the internal resistance of the particle to the heat transfer. The calcination efficiency results, as well as the practical experience gained in this study, indicated that the impinging-stream calciner may provide a promising tool for phosphate enrichment, and more generally, for processes involving gas-solid contact at high temperatures.  相似文献   
68.
The potential of processing and product innovations to alleviate the problem of declining quality of logs facing the Canadian softwood industry is examined. Comparative forecasts were made of the consequences of three technological investment strategies: continuation of present levels, increased investment in processing R&D, and increased investment in product R&D. The study identified a mixed strategy of investment in both processing and product technologies as the best approach for the Canadian softwood lumber industry to maintain profitability and market share in the markets in which it competes with US producers  相似文献   
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In order to help keep readers up‐to‐date in the field, each issue of Progress in Photovoltaics will contain a list of recently published journal articles that are most relevant to its aims and scope. This list is drawn from an extremely wide range of journals, including IEEE Journal of Photovoltaics, Solar Energy Materials and Solar Cells, Renewable Energy, Renewable and Sustainable Energy Reviews, Journal of Applied Physics, and Applied Physics Letters. To assist the reader, the list is separated into broad categories, but please note that these classifications are by no means strict. Also note that inclusion in the list is not an endorsement of a paper's quality. If you have any suggestions please email Ziv Hameiri at ziv.hameiri@unsw.edu.au .  相似文献   
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