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151.
案例教学作为一种教学方法,早已广泛应用于医学、工商管理、计算机等各个专业领域中。尤其在计算机领域,案例的选择是否恰当尤为重要,是关系到案例教学是否能取得预期成效的关键因素。本文就审计案例教学中教学案例的设计过程进行了探讨。提出依据变量互补性标准来选择和设计教学案例,引导学生体验实验的过程,完善自身的认知结构,给学生足够的时间,真正实现自主学习。 相似文献
152.
153.
基于计算机本科专业人才培养总体规划,根据学生的个体差异,研究探讨一种数据库课程的分类教学与实践模式,将学生分为不同类型,在授课、实验、课程设计和课后活动等方面分类实施不同的教学内容和实践安排,充分调动学生的学习积极性和主动性。 相似文献
154.
在MIS系统中,使用存储过程可以优化对数据库的访问,恰当地使用存储过程,既可以简化应用程序的开发,又可以增强MIS系统的灵活性与安全性。 相似文献
155.
Wei-Chu Weng 《Advances in Engineering Software》2011,42(6):398-407
In this paper, we propose and implement a website of post-processing system for finite element analysis (WebDFEA). Finite element analysis is a computer-aided engineering tool and is popular for static/dynamic structure analysis. It includes three processing systems where post-processing system is to graphically demonstrate the analysis result of a structure model analyzed by finite element method. WebDFEA performs as a website. It is cross-platform because it can auto-detect a client computer platform and auto-download proper OpenGL API for drawing computer graphics. It can draw precise graphics on webpage which can be free controlled by the mouse as a manner in professional software. A database server is involved to store finite element model data and its analysis result. The graphic user interface (GUI) of WebDFEA is a flexible GUI comprising three parts: the switch buttons designed by HTML, the display board and the color bar both developed in Java. The three components are independent and cooperative with each other. They can be recombined without running errors for different purposes. A ship hull section with half a hatch is chosen as the study case to test WebDFEA website. Its finite element model comprises 11,442 triangle elements (shapes). The timeframe starting when WebDFEA is connected to the end when the model is demonstrated is acceptable. 相似文献
156.
Preventive measures sometimes fail to defect malicious attacks. With attacks on data-intensive applications becoming an ever more serious threat, intrusion tolerant database systems are a significant concern. The main objective of such systems is to detect attacks, and to assess and repair the damage in a timely manner. This paper focuses on efficient damage assessment and repair in distributed database systems. The complexity caused by data partition, distributed transaction processing, and failures makes intrusion recovery much more challenging than in centralized database systems. This paper identifies the key challenges and presents an efficient algorithm for distributed damage assessment and repair. 相似文献
157.
C. A. Johnson 《Journal of Automated Reasoning》2009,42(1):35-76
A method is presented for computing minimal answers of the form in disjunctive deductive databases under the disjunctive stable model semantics. Such answers are constructed by repeatedly
extending partial answers. Our method is complete (in that every minimal answer can be computed) and does not admit redundancy
(in the sense that every partial answer generated can be extended to a minimal answer), thus no non-minimal answer is generated.
The method does not (necessarily) require the computation of models of the database in their entirety. A partitioning of the
database into extensional and intensional components is employed in order to overcome the problems caused by the possible
non-existence of disjunctive stable models, and a form of compilation is presented as a means of simplifying and improving
the efficiency of the run-time computation, which then reduces to relatively trivial processing within the extensional database.
In addition, the output from this compilation process has the significant advantage of being immune to updates to the extensional
database. Other forms of database pre-processing are also considered, and three transformations are presented mapping a database
onto an equivalent positive database, non-disjunctive database, and set of conditional facts. 相似文献
158.
159.
A near-optimal database allocation for reducing the average waiting time in the grid computing environment 总被引:1,自引:0,他引:1
In a grid computing environment, a great many users may access the same database simultaneously. To reduce the average waiting time for all users, a grid designer usually replicates the frequently accessed database among nodes based on the load balance heuristic. On the other hand, users may raise identical queries regarding an issue of interest, e.g., stock information, on a database and each of the queries will be directed to any node having a replica of that database. That is, the same answer will be determined by multiple nodes. Consequently, there exist two shortcomings of poor data sharing and duplicate calculations if the database is not replicated and allocated adequately. In this paper, we aim to minimize average waiting time and try to overcome the two shortcomings by performing database allocation over multiple nodes without any replication. The main idea behind the proposed method is to map the original problem to the Euclidean space Rn and to solve the mapped problem in Rn by a gradient-based optimization technique. The theoretical analyses ensure that the proposed method can converge linearly and achieve near-optimal results. 相似文献
160.
安钢中板厂的炉号跟踪系统中,冷金属检测器CMD用来检测冷床区钢坯的运动,但是CMD只能检测出辊道上是否有钢坯经过,而不能判断钢坯在冷床区具体上到哪个冷床,因此,目前冷床部分的钢坯跟踪是靠人工手动完成的.针对该问题,提出一种新的运用数字图像处理技术完成冷床区钢坯自动跟踪的方法.该方法利用运动目标检测方法检测出辊道上有钢坯运动,然后经过最佳阈值分割、改进的区域生长算法、质心标记、数据库程序等步骤完成钢坯运动轨迹的标记,实现自动跟踪. 相似文献