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51.
The authors investigated the structure of goal contents in a group of 1,854 undergraduates from 15 cultures around the world. Results suggested that the 11 types of goals the authors assessed were consistently organized in a circumplex fashion across the 15 cultures. The circumplex was well described by positing 2 primary dimensions underlying the goals: intrinsic (e.g., self-acceptance, affiliation) versus extrinsic (e.g., financial success, image) and self-transcendent (e.g., spirituality) versus physical (e.g., hedonism). The circumplex model of goal contents was also quite similar in both wealthier and poorer nations, although there were some slight cross-cultural variations. The relevance of these results for several theories of motivation and personality are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
52.
A taxonomy for and analysis of multi-person-display ecosystems   总被引:2,自引:2,他引:0  
Interactive displays are increasingly being distributed in a broad spectrum of everyday life environments: they have very diverse form factors and portability characteristics, support a variety of interaction techniques, and can be used by a variable number of people. The coupling of multiple displays creates an interactive “ecosystem of displays”. Such an ecosystem is suitable for particular social contexts, which in turn generates novel settings for communication and performance and challenges in ownership. This paper aims at providing a design space that can inform the designers of such ecosystems. To this end, we provide a taxonomy that builds on the size of the ecosystem and on the degree of individual engagement as dimensions. We recognize areas where physical constraints imply certain kinds of social engagement, versus other areas where further work on interaction techniques for coupling displays can open new design spaces.  相似文献   
53.
What are the prospects for meaningful learning in high-level creativity? An expertise acquisition view of creativity is optimistic about longitudinal improvement; a "Darwinian" view, emphasizing chance, is not. To address this issue, the complete outputs of 65 eminent composers (15,657 works) were tabulated and weighted; each work's masterpiece status was operationalized by citation and recording count measures. Works were assigned to 5-year age intervals, synchronized across composers by age at 1st masterwork. Hit ratio (masterwork-level music divided by total output) was calculated for each interval for each composer. The overall hit ratio trajectory was a single-peaked function, with a maximum around age 50. Reliable age effects held even during composers' mature periods, inconsistent with the chance view and more consistent--although not entirely so--with the expertise acquisition view. Several variables predicted individual differences in hit ratio trajectories; most notably, composers who wrote their best works later in their careers showed stronger agewise increases in hit ratio during their mature periods, even when best works were removed from the trajectories. Implications and prospects for reconciling the expertise and chance views, via a typology of conceptualist versus experimentalist creators, are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
54.
粗粒硫酸盐渍土冻融循环盐胀性研究   总被引:1,自引:0,他引:1  
为研究经多次冻融循环后粗拉硫酸盐渍土的盐胀特性及作为路基填料的适用性,采用室内冻融循环试验.在不同含水率、不同温度条件下,对硫酸盐渍土的盐胀性进行分析研究.试验结果表明:硫酸盐渍土的盐胀变形与含水量及温度有重要关系,并且盐胀量随着含水量的增加而增加,而当含水量一旦超过了最佳含水量后,盐胀量呈减少趋势;当含水率为4.0%的粗颗粒硫酸盐渍土在15-5℃降温区间,结晶比较活跃;当含水率超过最佳含水量时,在15-5℃降温区间土体容易发生塌陷.  相似文献   
55.
Pervasive systems are large-scale systems consisting of many sensors capturing numerous types of information. As this data is highly voluminous and dimensional, data analysis tasks can be extremely cumbersome and time-consuming. Enabling computers to recognise real-world situations is an even more difficult problem, involving not only data analysis, but also consistency checking. Here we present Situvis, an interactive visualisation tool for representing sensor data and creating higher-level abstractions from the data. This paper builds on previous work, Clear et al. (2009) [8] through evolved tool functionality and an evaluation of Situvis. A user-trial consisting of 10 participants shows that Situvis can be used to complete the key tasks in the development process of situation specifications in over 50% less time than an improvised alternative toolset.  相似文献   
56.
Proof-carrying code (PCC) and other applications in computer security require machine-checkable proofs of properties of machine-language programs. The main advantage of the PCC approach is that the amount of code that must be explicitly trusted is very small: it consists of the logic in which predicates and proofs are expressed, the safety predicate, and the proof checker. We have built a minimal proof checker, and we explain its design principles and the representation issues of the logic, safety predicate, and safety proofs. We show that the trusted computing base (TCB) in such a system can indeed be very small. In our current system the TCB is less than 2,700 lines of code (an order of magnitude smaller even than other PCC systems), which adds to our confidence of its correctness.  相似文献   
57.
58.
The broad adoption of diagnostic and analytical techniques in the field of archeology, presents a unique opportunity for e-Science in the form of scientific explanation, drawing from methodologies aimed at recording, archiving, analyzing, and disseminating, rich data collections to create the needed infrastructure for both research and web-based curation and data management system. This paper presents a needed stepping stone towards synergy between information technology and archeology, by introducing a data acquisition, tagging and characterization pipeline along with a novel method for spatially querying archeological data.  相似文献   
59.
We present a new methodology for agent modeling that is scalable and efficient. It is based on the integration of nonlinear dynamical systems and kinetic data structures. The method consists of three layers, which together model 3D agent steering, crowds and flocks among moving and static obstacles. The first layer, the local layer employs nonlinear dynamical systems theory to models low-level behaviors. It is fast and efficient, and it does not depend on the total number of agents in the environment. This dynamical systems-based approach also allows us to establish continuous numerical parameters for modifying each agent's behavior. The second layer, a global environment layer consists of a specifically designed kinetic data structure to track efficiently the immediate environment of each agent and know which obstacles/agents are near or visible to the given agent. This layer reduces the complexity in the local layer. In the third layer, a global planning layer, the problem of target tracking is generalized in a way that allows navigation in maze-like terrains, avoidance of local minima and cooperation between agents. We implement this layer based on two approaches that are suitable for different applications: One approach is to track the closest single moving or static target; the second is to use a pre-specified vector field, which may be generated automatically (with harmonic functions, for example) or based on user input to achieve the desired output. We also discuss how hybrid systems concepts for global planning can capitalize on both our layered approach and the continuous, reactive nature of our agent steering.

We demonstrate the power of the approach through a series of experiments simulating single/multiple agents and crowds moving towards moving/static targets in complex environments.  相似文献   

60.
Social networking site (SNS) use decisions have led to major economic and social transformations worldwide. While many organizations seek to use SNSs from a strategic perspective to reach their customer, it is important to understand what makes SNSs successful in order to use them for competitive purposes. The current research evaluates the influence of the social capital theory on SNS success measures. A model was developed and empirically tested using two data samples to ensure valid and reliable results for success of SNSs. The results display the importance of social capital in SNS success followed by practitioner and academic implications.  相似文献   
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