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81.
网络与终端协同选择及切换机制的研究 总被引:1,自引:1,他引:0
提出了一种智能切换机制,用于实现在异构网络中网络与终端的协同选择及切换功能。随着各种业务和应用的发展,异构网络融合是信息和通信技术的必然趋势。根据多接入、多终端等应用环境的要求,采用AHP与URA等多属性决策理论,为用户选择最佳的目标网络和目标终端,并提出相应的智能切换信令流程,包括网络切换、终端切换、网络与终端联合切换方式,最终构建以用户为中心的多终端智能空间,实现个人移动性管理。仿真表明,该智能切换机制可以有效地实现网络和终端的协同选择,并可以保证在异构网络切换QoS性能,为现代服务业的业务及应用的发展提供可靠的理论依据。 相似文献
82.
应用系统信息集成是管控一体化的研究热点。本文分析了跨级别应用系统信息集成的目标和面临的问题,结合Web服务的技术特性,提出一种基于Web服务进行异构系统信息集成的方法,最后给出了一个实际应用案例来验证该方法。 相似文献
83.
A new approach, called the “variational theory of complex rays” has been developed in order to calculate the vibrations of slightly damped elastic plates in the medium-frequency range. The resolution of a small system of equations which does not result from a fine spatial discretization of the structure leads to the evaluation of effective quantities (deformation energy, vibration amplitude,…). Here, we extend this approach, which was already validated for assemblies of homogeneous substructures, to the case of heterogeneous substructures. 相似文献
84.
85.
智能楼宇综合管理系统的设计 总被引:7,自引:0,他引:7
首先介绍了智能楼宇系统集成的问题,然后对智能楼宇综合管理系统的体系结构进行了设计分析了其特点,最后对其关键技术进行了研究。 相似文献
86.
This paper explores the suitability of the emerging passive star-coupled optical interconnection using wavelength division multiplexing as the system interconnect to provide high bandwidth (Gbits/sec) communication demanded by heterogeneous systems. Several different communication strategies (combinations of communication topologies and protocols) are investigated under a representative master-slave computational model. The interplay between system speed, network speed, task granularity, and degree of parallelism is studied using both analytical modeling and simulations. It is shown that a hierarchical ALOHA-based communication strategy between the master and the slaves, implemented on top of the passive star-coupled network, leads to a considerable reduction in channel contention and provides 50–80% reduction in task completion time for applications with medium to high degrees of coarse grain parallelism. Comparable reduction in channel contention is also shown to be achieved by using tunable acoustooptic filters at master nodes. 相似文献
87.
Richard F. Paige 《Formal Aspects of Computing》1998,10(3):233-242
We outline an extendible approach for combining formal methods – such as Z, Morgan's refinement calculus, and predicative
programming – based on composing specifications written in similar formal languages. We discuss how algorithm refinement can
be extended to such a setting, and outline some examples of using integrated formal methods. We also provide justifications
for why using combinations of similar methods might be helpful.
Received November 1996 / Accepted in revised form August 1998 相似文献
88.
A technique for scheduling and processor allocation leading to the synthesis of integrated heterogeneous pipelined processing elements, implementing digital signal processing applications, is proposed. The proposed technique achieves efficient hardware implementations at the logic-level by minimizing the number of processing units used, without compromising the rate and delay optimality criteria.
The proposed algorithm is found to outperform algorithms resulting in homogeneous implementations, as it gives schedules with lower iteration periods, requires less hardware resources, and has lower time complexity at design time. In comparison with the already existing heterogeneous algorithms, the proposed algorithm produces schedules of lower time complexity and lower iteration period for some applications. The optimal performance of the proposed algorithm has been verified on several benchmarks. 相似文献
89.
Preparation and characterisation of titanium dioxide films for catalytic applications generated by anodic spark deposition 总被引:1,自引:0,他引:1
The advanced plasma electrochemical process of anodic spark deposition (ASD) was used to generate photoactive titanium dioxide films on titanium metal substrates. A shift to easier-to-machine substrates was demonstrated by the deposition of a titanium film with physical vapour deposition onto different materials such as glass, silicon, and stainless steel prior to ASD. Obtained films were characterised by scanning electron microscopy, surface area measurement (Brunnauer-Emmett-Teller method, BET), X-ray diffraction, electron-probe microanalysis, and glow discharge spectroscopy. Additionally, film thickness was determined by eddy current measurements. Standard ASD conditions were defined as 180 V applied voltage over a 180 s hold time, a voltage ramp of 20 V/s, a duty cycle of 0.5 and a frequency of 1500 Hz. Most prominent characteristics of the titanium films produced under these standard conditions are a film thickness of ≤80 μm, a surface area of approximately 51 m2/g (BET) and an anatase content of approximately 30% and rutile content of approximately 70%. Furthermore, the film formation process is elucidated and the dependence of film thickness on deposition time and the dependence of the anatase and rutile content on the deposited mass are shown for varying ASD conditions. 相似文献
90.
There appear more critical requirements for special functions of components/products in various areas, which can be satisfied only by using heterogeneous materials and/or smart materials. The heterogeneous materials include composite materials, functionally graded materials, and heterogeneous materials with a periodic microstructure. To design and manufacture the components made of these materials, the computer models for representing them need first to be built so that further analysis, optimization and manufacturing can be implemented based on the models. This paper develops such a modeling method, which can be implemented by employing the functions of current CAD graphic software and obtain the model that includes all the material information (about periodic microstructures, constituent composition, inclusions, and embedded parts) along with geometry information in 3D solid modeling without the problem arising from too much data. 相似文献