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151.
152.
Microsoft office系列软件在日常工作中应用广泛。我单位在工程项目中大量使用Office软件进行数据处理及交换,对这些原始数据采取适当的方法分析挖掘,可以极大地缩短设计与试验周期、降低成本。由于项目产生的临时数据常以不同格式存放在各种办公软件中,且数量巨大,所以需要一个可以控制Office系列办公软件的程序来完成原始信息的收集及输出。给出了通过使用基于C++的Qt框架并结合COM、ODBC技术获取、处理数据,并输出至数据库或XML文档的实现方法。 相似文献
153.
154.
WebGIS网络地理信息系统是Internet技术应用于GIS地理信息系统开发的产物.在互联网环境下,以Web页面作为GIS软件的用户界面,把Internet和GIS技术结合在一起,可为各种地理信息应用提供GIS功能,以提高系统性能,使用户共享互联网资源.为此,在开源软件的基础上,通过使用GeoServer、PostGIS数据库和OpenLayers实现了WebGIS的展示层、处理层和数据层三层体系框架. 相似文献
155.
水源区生态补偿机制理论框架研究 总被引:2,自引:1,他引:1
建立和完善水源区生态补偿机制,对保护水源区生态环境以及地区之间的协调可持续发展至关重要。在总结前人研究成果的基础上,从生态保护成本(或效益)外部性问题内部化,依据"公平、公开、公正"和"谁受益谁补偿、谁破坏谁治理"的原则,提出了水源区生态补偿概念;从生态补偿主客体的划分,补偿标准,补偿模式与补偿方式,补偿保障措施等方面提出了水源区生态补偿机制理论框架,为建立和完善水源区生态补偿机制提供理论参考。 相似文献
156.
Combining intensional with extensional query evaluation in tuple independent probabilistic databases
In this paper, we prove that a query plan is safe in tuple independent probabilistic databases if and only if its every answer tuple is tree structured in probabilistic graphical models. We classify hierarchical queries into core and non-core hierarchical queries and show that the existing methods can only generate safe plans for core hierarchical queries. Inspired by the bucket elimination framework, we give the sufficient and necessary conditions for the answer relation of every candidate sub-query to be used as a base relation. Finally, the proposed algorithm generates safe plans for extensional query evaluation on non-boolean hierarchical queries and invokes the SPROUT algorithm [24] for intensional query evaluation on boolean queries. A case study on the TPC-H benchmark reveals that the safe plans of Q7 and Q8 can be evaluated efficiently. Furthermore, extensive experiments show that safe plans generated by the proposed algorithm scale well. 相似文献
157.
Computer modeling of blood flows in the arteries is an important and very challenging problem. In order to understand, computationally, the sophisticated hemodynamics in the arteries, it is essential to couple the fluid flow and the elastic wall structure effectively and specify physiologically realistic boundary conditions. The computation is expensive and the parallel scalability of the solution algorithm is a key issue of the simulation. In this paper, we introduce and study a parallel two-level Newton–Krylov–Schwarz method for simulating blood flows in compliant branching arteries by using a fully coupled system of linear elasticity equation and incompressible Navier–Stokes equations with the resistive boundary condition. We first focus on the accuracy of the resistive boundary condition by comparing it with the standard pressure type boundary condition. We then show the parallel scalability results of the two-level approach obtained on a supercomputer with a large number of processors and on problems with millions of unknowns. 相似文献
158.
A new approach is introduced for turbidite modeling, leveraging the potential of computational fluid dynamics methods to simulate the flow processes that led to turbidite formation. The practical use of numerical flow simulation for the purpose of turbidite modeling so far is hindered by the need to specify parameters and initial flow conditions that are a priori unknown. The present study proposes a method to determine optimal simulation parameters via an automated optimization process. An iterative procedure matches deposit predictions from successive flow simulations against available localized reference data, as in practice may be obtained from well logs, and aims at convergence towards the best-fit scenario. The final result is a prediction of the entire deposit thickness and local grain size distribution. The optimization strategy is based on a derivative-free, surrogate-based technique. Direct numerical simulations are performed to compute the flow dynamics. A proof of concept is successfully conducted for the simple test case of a two-dimensional lock-exchange turbidity current. The optimization approach is demonstrated to accurately retrieve the initial conditions used in a reference calculation. 相似文献
159.
Ning MaAuthor Vitae Zhonghai LuAuthor VitaeLirong ZhengAuthor Vitae 《Microprocessors and Microsystems》2011,35(2):217-229
Future multimedia applications such as full HD (1920 × 1080) multiview video coding (MVC) present great challenges on computing architectures. Even if with the state-of-the-art ASIC technology which can process single view HD decoding, dealing with multiple views would require times of computation capacity in proportion to the number of views, which is difficult to achieve. In this paper, we explore the system-level design space for full HD MVC applications mapped onto mesh-based multicore Network-on-Chip (NoC) architectures. To this end, we establish a simulation framework capable of simulating the combination of communication networks with computing cores. We investigate two task assignment schemes: picture-level assignment and view-level assignment. With an eight-view MVC decoding, we explore the design options with respect to network size, single-core performance and link bandwidth under both task assignment schemes. Our studies show that, to achieve a certain decoding performance, the computation capability and communication capacity should be balanced in the system. Also, to realize the eight-view HD decoding, the system only requires twice or less than twice of the single-core processing capacity required by single view decoding, thanks to the parallel computation and communication enabled by the multicore NoC architectures. Our results exhibit feasibility and potential of efficiently implementing the full HD MVC decoding on multicore NoC architectures. 相似文献
160.
辩论框架是计算机利用辩论机制来解决实际问题的基础,如商务谈判、法律纠纷和劳动争议等。传统的辩论框架对辩论机制和论证方法作了具体的形式化描述,但忽略了辩论主体及其对辩论结果影响的描述,而且在辩论过程中一个论点通常需要多个论据的联合论证。针对以上问题,在传统辩论框架的基础上,提出了一种基于主体可信度的联合辩论框架(STUAF)。首先引入了辩论主体的概念,并对观点和论据之间的联合论证进行形式化定义;其次给出了完整的框架结构和语义描述,证明了该辩论框架满足Dunk提出的标准辩论框架的基本定理;然后结合辩论树给出了语义计算的算法;最后给出一个具体的应用实例,实例分析表明S I'UAF及其语义算法是有效的。 相似文献