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101.
Presented 20 3rd- and 65 4th-grade Ss with a referential communication task in which they were required to generate a clue for an imaginary listener that would allow the listener to know which of 2 similar words (e.g., baby-child) was the referent. The optimal strategy for the task involved (a) generating an associate to the referent, (b) comparing the candidate clue with the referent and nonreferent, and (c) evaluating whether the clue was more highly associated with the referent than with the nonreferent. Children do not spontaneously carry out the comparison and evaluation components of this optimal strategy. Ss in the present complete instruction condition were taught to both compare and evaluate; their performance exceeded control performance for both easy and difficult materials. Comparison or evaluation training alone produced better clue production only for easy materials. Results are relevant to theoretical claims about referential communication and to the hypothesis that strategy instruction with schoolchildren should be elaborated and complete. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
102.
Most software packages available for particle tracing focus on visualizing steady or unsteady vector fields by using massless particle trajectories. For many applications, however, the use of massed and evaporating particles would provide a model of physical processes that could be used in product testing or design. In this article we describe the TrackPack toolkit, which provides an integrated interface for computing massless, massed, and evaporating particle trajectories in steady flow. In all cases, we assume a noncoupled model and compute particle trajectories through an existing vector field by numerically integrating with forward Euler, fourth-order Runge-Kutta, or an analytic streamline calculation. The TrackPack software effort was motivated by an industrial application to model pollution control systems in industrial boilers. We briefly describe the project and the visualization environment, and we demonstrate the necessity for massed, evaporating models in the application.  相似文献   
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This paper describes the analysis and generation grammars for English and Japanese as they were employed in the KBMT-89 program. We discuss word order, coordination, subcategorization, morphological rules, rule ordering and bi-directional grammars.  相似文献   
106.
This article evaluated the ability of propranolol to enhance results achieved with relaxation-biofeedback training. Thirty-three patients were randomized to relaxation-biofeedback training alone (administered in a limited-contact treatment format), or to relaxation-biofeedback training accompanied by long-acting propranolol (with dosage individualized at 60, 120, or 180 mg/day). Concomitant propranolol therapy significantly enhanced the effectiveness of relaxation-biofeedback training when either daily headache recordings (79% vs. 54% reduction in migraine activity) or neurologist clinical evaluations (90% vs. 66% reduction) were used to assess treatment outcome. Concomitant propranolol therapy also yielded larger reductions in analgesic medication use and greater improvements of quality of life measures than relaxation-biofeedback training alone but was more frequently associated with side effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
107.
Recent animal research has demonstrated that humans are not a uniquely aggressive species and that even in so-called violence-prone animals, aggression is always an optional strategy. Although some form of intraspecific aggression exists in every vertebrate species studied thus far, it is also true that all organisms have coevolved equally potent inhibitory mechanisms that enable them to use an aggressive strategy selectively or to suppress aggression when it is in their interest to do so. Parallel studies of aggression in children, assaultive adults, and even entire societies have suggested that humans are exquisitely sensitive to subtle social controls that could be used to reduce the frequency of individual acts of violence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
108.
Knowledge representation support   总被引:1,自引:1,他引:0  
The representation of world knowledge in a machine translation system is discussed, especially in terms of the interlingua text that is adopted in KBMT-89. While knowledge about the world is at the core of a knowledge-based machine translation program, it cannot be extracted from a text without knowledge about how languages encode it syntactically. The paper therefore also presents the grammar formalism with which language-specific syntactic knowledge is presented. Details are presented of our version of unification-based grammar, its basis in linguistic theory and its role in a knowledge-based machine translation system.  相似文献   
109.
Because human immunodeficiency virus type 1 (HIV-1) infection is characterized by a large number of viral replication cycles and rapid cell turnover in vivo, successful gene therapy requires an approach effective under these conditions. The antitat gene has been proposed for gene therapy because it effectively blocks Tat function and the replication of HIV-1. However, neither antitat nor any other antiviral gene has been shown to inhibit HIV in the presence of high viral load and inflammatory cytokines, a condition closer to the in vivo situation. We show that cells transduced with antitat retrovirus vector are resistant to high multiplicity of HIV infection. In the presence of inflammatory cytokines, including interleukin-1 and tumor necrosis factor, both known to activate viral gene expression independently of Tat, antitat suppressed virus replication. HIV-1 inhibition was observed when cell were treated with a mixture of inflammatory cytokines able to induce acquired immunodeficiency syndrome (AIDS) Kaposi's sarcoma cell growth. These molecules have been shown to be increased in HIV-1-infected individuals, and it is suggested they play a role in the pathogenesis of AIDS. Our results suggest that antitat is effective under conditions present in vivo and therefore a primary candidate for HIV-1 gene therapy.  相似文献   
110.
A method for predicting the highly nonlinear stress-strain behavior and dilatation induced by cavitation of highly filled particulate composites from constituent properties has been developed. The approach presented uses a variation of linear elasticity throughout and has no adjustable parameters, unlike the methods currently used, which require large numbers of fitting factors and complicated nonlinear analyses. An energy balance derived from the first law of thermodynamics calculates critical strain values at which filler particles will debond when subjected to deformation. Repeated calculations of critical strain values using re-evaluated material properties accounting for the damage caused by debonding give very nonlinear stress-strain and dilatation curves. Experimentally observed dependencies on particle size, filler concentration, adhesion, and matrix and filler properties are correctly predicted. The method can be generalized for any state of stress or particle shape. Comparisons of experimental data with the model results give good agreement.  相似文献   
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