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51.
52.
Knowledge-based computing, in general, suffers from an inherent open-endedness that precludes its application in time-bounded domains where an answer must be computed within a stipulated time limit. We examine a two-way improvement of the shortcomings: a knowledge representation scheme that provides easy access to relevant knowledge and thereby reduces search time, and a reasoning scheme that is algorithmic in nature and thus makes computational requirements meaningfully estimable.In this work, we offer a cache-based architecture that is capable of both storing knowledge in different formats (e.g. rules, cases), and invoking an appropriate reasoning scheme to fit the available computing time. The cache helps in retrieving the most relevant pieces of knowledge (not only exact matches) required for solving a given problem. This cache relies on a reasoning tactic, knowledge interpolation, that can generate a solution from two near-matches in an algorithmic way, to generate time-bounded solutions. We illustrate the design of such a cache for solving resource allocation problems in the domain of shortwave radio transmission and evaluate its performance in observing imposed temporal bounds. 相似文献
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We introduce a general and in a certain sense time-optimal way of solving one problem after another, efficiently searching the space of programs that compute solution candidates, including those programs that organize and manage and adapt and reuse earlier acquired knowledge. The Optimal Ordered Problem Solver (OOPS) draws inspiration from Levin's Universal Search designed for single problems and universal Turing machines. It spends part of the total search time for a new problem on testing programs that exploit previous solution-computing programs in computable ways. If the new problem can be solved faster by copy-editing/invoking previous code than by solving the new problem from scratch, then OOPS will find this out. If not, then at least the previous solutions will not cause much harm. We introduce an efficient, recursive, backtracking-based way of implementing OOPS on realistic computers with limited storage. Experiments illustrate how OOPS can greatly profit from metalearning or metasearching, that is, searching for faster search procedures. 相似文献
56.
A contribution to the development of strategic control and planning instruments: An acquisition case study 总被引:1,自引:0,他引:1
A. Chevalier P. L. Kunsch J. P. Brans 《International Transactions in Operational Research》2004,11(2):155-168
The present paper is part of the efforts made by the authors in recent years to develop strategic control and planning instruments in corporations using OR‐techniques like system dynamics, control theory, and group multicriteria decision aid. A more general framework called ‘adaptive control methodology’ (ACM) combines all these techniques. It has been presented in several papers. The objective of the present analysis is to calibrate this instrument and to tune it to the corporate needs by analysing real‐world applications. More specifically, several case studies have been investigated in large multinational organisations in the food sector. An acquisition case has been used for the calibration purpose. It is analysed in the paper from the ACM perspective to provide additional material for revisiting and improving the methodology. 相似文献
57.
Fabrication process of open surfaces by robotic fibre placement 总被引:3,自引:2,他引:3
Composite materials are being used extensively in many industrial sectors. They offer excellent material properties compared to other structural materials available. However, the traditional fabrication process using manual hand lay-up is time consuming and labour intensive. Therefore, robotic fibre placement has been introduced to overcome these drawbacks. This approach may greatly reduce cycle time and manufacturing costs. This paper describes the overall strategy for the establishment of a flexible robotic fibre placement technique. The fabrication process planning of this new technique is presented. Three different types of fibre placement for open surfaces are discussed. These include simulation-based fibre path generation, fibre steering, and sensory-based contour following methodologies. The system architecture for the process control is also presented. 相似文献
58.
怒江水电基地的电力市场研究 总被引:1,自引:0,他引:1
怒江中下游干流河段落差集中 ,水量大 ,淹没损失小 ,交通方便 ,施工条件好 ,地质条件良好。规划装机容量2 13 2 0MW ,是我国重要的水电基地之一。到 2 0 2 0年 ,澜沧江中下游、金沙江中下游以及广西水电、四川水电、贵州水电基本得到大规模的开发 ;怒江将可能成为南方电网 ,乃至华中电网电力电量平衡的必不可少的电源。怒江水电基地是南方电网长远能源平衡的战略基地 ,“西电东送”的后续基地。怒江供电区域市场空间较大 ,送到受电地区的落地电价也具备一定的竞争力 相似文献
59.
Chul Kim Chul Woo Park 《The International Journal of Advanced Manufacturing Technology》2006,29(5-6):459-474
This paper deals with an automated computer-aided process planning and die design system by which the designer can determine
operation sequences even if they have little experience in process planning and die design for axisymmetric products. An attempt
is made to link programs incorporating a number of expert design rules with the process variables obtained by commercial FEM
softwares, DEFORM and ANSYS, to form a useful package. The system is composed of four main modules. The process planning and
the die design modules consider several factors, such as the complexities of preform geometry, punch and die profiles, specifications
of available multi-former, and the availability of standard parts. They can provide a flexible process based on either the
reduction in the number of forming sequences by combining the possible two processes in sequence, or the reduction of deviation
of the distribution on the level of the required forming loads by controlling the forming ratios. In the die design module
optimal design technique and the horizontal split of the die insert were investigated for determining appropriate dimensions
of components of the multi-former die set. It is suggested that the proposed method can be beneficial for improving the tool
life of the die set in practice. 相似文献
60.
L. H. S. Luong T. Spedding 《The International Journal of Advanced Manufacturing Technology》1995,10(6):411-415
The process planning function plays a critical role not only in computer integrated manufacture, but also in the economics of batch manufacturing. This paper describes the development of a generic knowledge-based system for process planning and cost estimation in the hole making process. The main function of the system, besides estimating the cost of production, is to recommend appropriate processes, their sequence and their respective machining conditions in order to obtain the required product specifications. The system has been implemented in a manufacturing organisation. The results obtained have indicated that in addition to cost savings the system also preserves the consistency in planning and cost estimation. 相似文献