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571.
Three high volume septic systems in Ontario, Canada, were examined to assess the potential for onsite wastewatertreatment systems to release pharmaceutical compounds to the environment and to evaluate the mobility of these compounds in receiving aquifers. Wastewater samples were collected from the septic tanks, and groundwater samples were collected below and down gradient of the infiltration beds and analyzed for a suite of commonly used pharmaceutical and trace organic compounds. The septic tank samples contained elevated concentrations of several pharmaceutical compounds. Ten of the 12 compounds analyzed were detected in groundwater at one or more sites at concentrations in the low ng L(-1) to low microg L(-1) range. Large differences among the sites were observed in both the number of detections and the concentrations of the pharmaceutical compounds. Of the compounds analyzed, ibuprofen, gemfibrozil, and naproxen were observed to be transported atthe highest concentrations and greatest distances from the infiltration source areas, particularly in anoxic zones of the plumes.  相似文献   
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Moving beyond simply documenting that political violence negatively impacts children, we tested a social–ecological hypothesis for relations between political violence and child outcomes. Participants were 700 mother–child (M = 12.1 years, SD = 1.8) dyads from 18 working-class, socially deprived areas in Belfast, Northern Ireland, including single- and two-parent families. Sectarian community violence was associated with elevated family conflict and children's reduced security about multiple aspects of their social environment (i.e., family, parent–child relations, and community), with links to child adjustment problems and reductions in prosocial behavior. By comparison, and consistent with expectations, links with negative family processes, child regulatory problems, and child outcomes were less consistent for nonsectarian community violence. Support was found for a social–ecological model for relations between political violence and child outcomes among both single- and two-parent families, with evidence that emotional security and adjustment problems were more negatively affected in single-parent families. The implications for understanding social ecologies of political violence and children's functioning are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
574.
Designs almost always require tradeoffs between competing design choices to meet system requirements. We present a framework for evaluating design choices with respect to meeting competing requirements. Specifically, we develop a model to estimate the performance of a UML design subject to changing levels of security and fault-tolerance. This analysis gives us a way to identify design solutions that are infeasible. Multi-criteria decision making techniques are applied to evaluate the remaining feasible alternatives. The method is illustrated with two examples: a small sensor network and a system for controlling traffic lights. Dr. Anneliese Amschler Andrews is Professor and Chair of the Department of Computer Science at the University of Denver. Before that she was the Huie Rogers Endowed Chair in Software Engineering at Washington State University. Dr. Andrews is the author of a text book and over 130 articles in the area of Software Engineering, particularly software testing and maintenance. Dr. Andrews holds an MS and PhD from Duke University and a Dipl.-Inf. from the Technical University of Karlsruhe. She served as Editor-in-Chief of the IEEE Transactions on Software Engineering. She has also served on several other editorial boards including the IEEE Transactions on Reliability, the Empirical Software Engineering Journal, the Software Quality Journal, the Journal of Information Science and Technology, and the Journal of Software Maintenance. She was Director of the Colorado Advanced Software Institute from 1995 to 2002. CASI's mission was to support technology transfer research related to software through collaborations between industry and academia. Ed Mancebo studied software engineering at Milwaukee School of Engineering and computer science at Washington State University. His masters thesis explored applying systematic decision making methods to software engineering problems. He is currently a software developer at Amazon.com. Dr. Per Runeson is a professor in software engineering at Lund University, Sweden. His research interests include methods to facilitate, measure and manage aspects of software quality. He received a PhD from Lund University in 1998 and has industrial experience as a consulting expert. He is a member of the editorial board of Empirical Software Engineering and several program committees, and currently has a senior researcher position funded by the Swedish Research Council. Robert France is currently a Full Professor in the Department of Computer Science at Colorado State University. His research interests are in the area of Software Engineering, in particular formal specification techniques, software modeling techniques, design patterns, and domain-specific modeling languages. He is an Editor-in-Chief of the Springer journal on Software and System Modeling (SoSyM), and is a Steering Committee member and past Steering Committee Chair of the MoDELS/UML conference series. He was also a member of the revision task forces for the UML 1.x standards.  相似文献   
575.
Emerging hybrid chips containing cpu and FPGA components are an exciting new development promising commercial off-the-shelf economies of scale, while also supporting hardware customization.  相似文献   
576.
Myocardial nonesterified fatty acids (NEFA) increase markedly within the first two days after the induction of insulin-dependent diabetes mellitus in rats by intravenous injection of alloxan. After initial variability, NEFA levels in diabetic hearets remain constant at approximately 450 nmol/g tissue (16 nmol/gmmol lipid P), which is about three times higher than that in control hearts. Nonesterified linoleic acid is significantly increased in diabetic heart whereas both arachidonic and docosahexaenoic acids are decreased compared to controls.  相似文献   
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578.
This paper examines the cryptographic security of fixed versus random elliptic curves over GF(p). It assumes a precomputation for use in breaking the elliptic curve discrete logarithm problem (ecdlp) can be made for fixed curves. A lower bound for the efficiency of a variation of Pollards rho method for solving multiple ecdlps is presented, as well as an approximation of the expected time remaining to solve an ecdlp when a given size of precomputation is available. We conclude that adding 4 bits to the order of a fixed curve to avoid general software attacks plus 6 bits to avoid attacks on curves with special properties provides equivalent security.  相似文献   
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580.
We interviewed spinal-cord-injured, other handicapped, and nonhandicapped subjects to investigate the relation between the perception of autonomic arousal and experienced emotion. The three groups differed significantly on only one measure of affect intensity, with the spinal-cord-injured subjects more often reporting stronger fear in their lives now compared with the past. In addition, spinal-cord-injured subjects often described intense emotional experiences. Spinal-cord-injured subjects who differed in their level of autonomic feedback differed in intensity on several measures. Subjects with greater autonomic feedback tended to report more intense levels of negative emotions. The findings indicate that the perception of autonomic arousal may not be necessary for emotional experience. There were weak trends in our data, however, suggesting that the perception of arousal may enhance the experience of emotional intensity. The subjective well-being reports of the handicapped groups were comparable to those of nonhandicapped subjects, indicating successful coping with their disability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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