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151.
Apriori算法在学生成绩分析中的应用研究 总被引:1,自引:0,他引:1
高等学校积累了大量的学生成绩信息,而从成绩中得到的信息量相对较小,造成资源的极大浪费.利用关联规则挖掘算法Apriori,以学生成绩数据库作为研究对象,挖掘课程之间的相关关系,为教务部门设置安排课程提供理论指导. 相似文献
152.
教务管理系统作为数字化校园重要组成部分之一,是涉及教务管理各环节、面向学校各部门以及各层次用户的多模块综合管理信息系统。在使用中会产生大量的有用的和无用的数据,可以通过数据挖掘技术来对这些数据进行分析,从而达到高效、人性化的管理。 相似文献
153.
遗传算法在机械手轨迹优化过程中存在一定的缺陷,为了获得较理想的运动轨迹,提出了基于EDA优化算法的机械手运动轨迹优化算法。由于EDA算法中仅使用选择和基因池重组算子,因而常会过早收敛。为了改变这种不足,提出一种改进的EDA算法(IEDA),IEDA算法中使用了小生境技术来保持解的多样性,斌使用簇的方法保存优良个体。通过实验仿真,所得优化轨迹令人满意,且表现出优良特性。 相似文献
154.
This paper presents two new mathematical formulations for the point-feature cartographic label placement problem (PFCLP) and a new Lagrangean relaxation with clusters (LagClus) to provide bounds to these formulations. The PFCLP can be represented by a conflict graph and the relaxation divides the graph in small subproblems (clusters) that are easily solved. The edges connecting clusters are relaxed in a Lagrangean way and a subgradient algorithm improves the bounds. The LagClus was successfully applied to a set of instances up to 1000 points providing the best results of those reported in the literature. 相似文献
155.
Natashia Boland Barry D. Hughes Liam T.G. Merlot Peter J. Stuckey 《Computers & Operations Research》2008
The most complete form of academic timetabling problem is the population and course timetabling problem. In this problem, there may be multiple classes of each subject, and the decision on which students are to constitute each class is made in concert with the decision on the timetable for each class. In order to solve this problem, it is normally simplified or decomposed in some fashion. One simplification commonly used in practice is known as blocking: it is assumed that the classes can be partitioned into sets of classes (or blocks) that will be timetabled in parallel. This restricts clashing to occur only between classes in the same block, and essentially removes the timetabling aspect of the problem, which can be carried out once the blocks are constituted and the classes populated. The problem of constituting the blocks and populating the classes, known as the course blocking and population problem, is nevertheless a challenging problem, and provides the focus of this paper. We demonstrate, using data provided by a local high school, that integer linear programming approaches can solve the problem in a matter of seconds. Key features include remodelling to remove symmetry caused by students with identical subject selection, and the observation that in practice, only integrality of the block composition variables needs to be enforced; the class population aspects of the model have strong integrality properties. 相似文献
156.
This work describes the fabrication of ZrO2/Au nano-composite films and its application for voltammetric detection of organophosphate pesticides. The nano-composite ZrO2/Au film was prepared through a combination of sol–gel procedure and electroless plating that can be carried out in a general chemistry lab with no need for special facilities and reagents. The sensing performance of the ZrO2/Au nano-composite film electrode toward parathion was studied with square wave voltammetry. The nano-ZrO2 showed a strong affinity toward the phosphate group on parathion molecules, which provides sensitivity and selectivity of the sensing film. A linear relationship was obtained between the peak currents and the concentration of parathion, with a detection limit for standard samples of 3 ng/ml. In addition, interference studies showed that structurally similar compounds without phosphate groups would not interfere with the response toward parathion of the film electrode. 相似文献
157.
Enacting agent-based services for automated procurement 总被引:1,自引:0,他引:1
A. Giovannucci J.A. Rodríguez-Aguilar A. Reyes F.X. Noria Jesús Cerquides 《Engineering Applications of Artificial Intelligence》2008,21(2):183-199
Negotiation events in industrial procurement involving multiple, highly customisable goods pose serious challenges to buying agents when trying to determine the best set of providing agents’ offers. Typically, a buying agent's decision involves a large variety of constraints that may involve attributes of a very same item as well as attributes of different, multiple items. In this paper we present iBundler, an agent-aware service offered to buying agents to help them determine the optimal bundle of received offers based on their business rules. In this way, buying agents are relieved with the burden of solving too hard a problem and concentrate on strategic issues. iBundler is intended as a negotiation service for buying agents and as a winner determination service for reverse combinatorial auctions with side constraints. Furthermore, we assess the computational cost added by employing agent technology in the development of iBundler to characterise the type of negotiation scenarios that it can acceptably handle. 相似文献
158.
159.
给出一种新的自适应数字图像信息隐藏算法.在传统混合算法的基础上,根据公开图像本身的像素分布和颜色特点,对混合系数进行改变.算法结合图像的局部特征,充分利用人类视觉的各种掩蔽特性自适应地嵌入秘密信息,对原图像所作的改变具有很好的不可见性.算法简单、信息隐藏量大,且具有一定的鲁棒性. 相似文献
160.
翟红 《数字社区&智能家居》2009,(9)
随着电子技术的迅猛发展,新技术革命的教学改革的不断深入,电子设计自动化技术运用而生,使得电子线路的设计人员能在计算机上完成电路的功能设计、逻辑设计、性能分析、时序测试直到印刷电路板的自动设计,提高了电工电子开发的效率和周期。本文就是利用Multisim8仿真设计一个方波三角波函数发生器的电路着手,介绍了仿真设计过程及生成网络表后再利用protel99SE的PCB制板过程。 相似文献