全文获取类型
收费全文 | 2208篇 |
免费 | 56篇 |
国内免费 | 63篇 |
专业分类
电工技术 | 85篇 |
综合类 | 93篇 |
化学工业 | 118篇 |
金属工艺 | 152篇 |
机械仪表 | 301篇 |
建筑科学 | 123篇 |
矿业工程 | 29篇 |
能源动力 | 77篇 |
轻工业 | 130篇 |
水利工程 | 5篇 |
石油天然气 | 138篇 |
武器工业 | 25篇 |
无线电 | 224篇 |
一般工业技术 | 214篇 |
冶金工业 | 21篇 |
原子能技术 | 21篇 |
自动化技术 | 571篇 |
出版年
2024年 | 5篇 |
2023年 | 9篇 |
2022年 | 18篇 |
2021年 | 23篇 |
2020年 | 25篇 |
2019年 | 9篇 |
2018年 | 19篇 |
2017年 | 35篇 |
2016年 | 35篇 |
2015年 | 35篇 |
2014年 | 86篇 |
2013年 | 123篇 |
2012年 | 107篇 |
2011年 | 143篇 |
2010年 | 131篇 |
2009年 | 105篇 |
2008年 | 100篇 |
2007年 | 129篇 |
2006年 | 143篇 |
2005年 | 138篇 |
2004年 | 121篇 |
2003年 | 101篇 |
2002年 | 104篇 |
2001年 | 77篇 |
2000年 | 83篇 |
1999年 | 81篇 |
1998年 | 76篇 |
1997年 | 54篇 |
1996年 | 36篇 |
1995年 | 47篇 |
1994年 | 30篇 |
1993年 | 11篇 |
1992年 | 18篇 |
1991年 | 19篇 |
1990年 | 7篇 |
1989年 | 9篇 |
1988年 | 5篇 |
1987年 | 4篇 |
1986年 | 7篇 |
1985年 | 2篇 |
1984年 | 5篇 |
1983年 | 1篇 |
1980年 | 3篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1971年 | 1篇 |
排序方式: 共有2327条查询结果,搜索用时 16 毫秒
41.
随着软件规模的不断扩大,软件系统深入到社会的各个领域,软件安全性测试的需求也日益扩张。软件的安全性问题主要是由于语言和程序本身的缺陷带来的后遗症。指针和数组能够导致多种软件安全性缺陷,其中最有名的就是"缓存区的溢出"。详细介绍了由指针和数组能够引发的一些安全性缺陷模型,并探讨了为这些缺陷设计测试方案所遇到的问题及解决方法。 相似文献
42.
In this paper, we consider the robust interpretation of Metric Temporal Logic (MTL) formulas over signals that take values in metric spaces. For such signals, which are generated by systems whose states are equipped with non-trivial metrics, for example continuous or hybrid, robustness is not only natural, but also a critical measure of system performance. Thus, we propose multi-valued semantics for MTL formulas, which capture not only the usual Boolean satisfiability of the formula, but also topological information regarding the distance, ε, from unsatisfiability. We prove that any other signal that remains ε-close to the initial one also satisfies the same MTL specification under the usual Boolean semantics. Finally, our framework is applied to the problem of testing formulas of two fragments of MTL, namely Metric Interval Temporal Logic (MITL) and closed Metric Temporal Logic (clMTL), over continuous-time signals using only discrete-time analysis. The motivating idea behind our approach is that if the continuous-time signal fulfills certain conditions and the discrete-time signal robustly satisfies the temporal logic specification, then the corresponding continuous-time signal should also satisfy the same temporal logic specification. 相似文献
43.
Software reliability is one of the most important quality attributes of commercial software. During software testing, software reliability growth models (SRGMs) are commonly used to describe the phenomenon of failure occurrence and/or fault removal which consequently enhancements software reliability. Large software systems are developed by integrating a number of relatively small and independent modules, which are tested independently during module testing phase. The amount of testing resource available is limited which is desired to be consumed judiciously so as to optimize the testing process. In this paper we formulate a resource allocation problem of minimizing the cost of software testing under available amount of testing resource, given a reliability constraint. We use a flexible SRGM considering testing effort which, depending upon the values of parameters, can describe either exponential or S-shaped failure pattern of software modules. A systematic and sequential Algorithm is proposed to solve the optimization problem formulated. Numerical examples are given to illustrate the formulation and solution procedures. Sensitivity analysis is performed to examine the behavior of some parameters of SRGM with most significant influence. 相似文献
44.
该文介绍一种逻辑分析仪数据捕获模式的设计原理与实现方法。该模式主要用于嵌入式软件的测试分析,它不再采用采样的方式来采集数据,而是利用软件插桩与硬件设置触发字相结合的方法来监视系统总线。当程序运行到插桩点时,硬件将产生触发,此时才会主动地到总线上将相应数据与对应的具体时问捕获回来,从而实现有效数据的精确捕获。此外,在FPGA内部采用双RAM交替读写的方式来暂存数据,在不中断程序运行的情况下,实现有效数据的长时间实时存取与分析,提高嵌入式软件性能分析的范围和质量。采用FPGA作为构成硬件架构的基本功能器件,提高了工作速度,使整个设计具具有集成度高、性能稳定、调试方便等特点。该模块在实际应用中得到了验证,并取得了良好的效果。 相似文献
45.
Yannis Smaragdakis Christoph Csallner Ranjith Subramanian 《Automated Software Engineering》2009,16(1):73-99
We explore the automatic generation of test data that respect constraints expressed in the Object-Role Modeling (ORM) language.
ORM is a popular conceptual modeling language, primarily targeting database applications, with significant uses in practice.
The general problem of even checking whether an ORM diagram is satisfiable is quite hard: restricted forms are easily NP-hard
and the problem is undecidable for some expressive formulations of ORM. Brute-force mapping to input for constraint and SAT
solvers does not scale: state-of-the-art solvers fail to find data to satisfy uniqueness and mandatory constraints in realistic
time even for small examples. We instead define a restricted subset of ORM that allows efficient reasoning yet contains most
constraints overwhelmingly used in practice. We show that the problem of deciding whether these constraints are consistent
(i.e., whether we can generate appropriate test data) is solvable in polynomial time, and we produce a highly efficient (interactive
speed) checker. Additionally, we analyze over 160 ORM diagrams that capture data models from industrial practice and demonstrate
that our subset of ORM is expressive enough to handle their vast majority. 相似文献
46.
软件质量控制的群体协同工作模型 总被引:5,自引:1,他引:4
当前软件的开发离不开协同工作。文章通过研究软件开发各个阶段中所存在的各种角色,着重引出了三组角色:质量保证组、开发组和测试组,并在详细分析它们在软件开发过程中的相互作用的基础上,提出了一个软件质量控制的群体协同工作模型。 相似文献
47.
系统测试平台的设计与实现 总被引:3,自引:0,他引:3
文章针对系统测试任务的工作性质和工作需求,首先分析了分布式实时应用系统的系统测试的特征和要求,并结合国际上软件发展的趋势,提出了管理者/代理系统测试模型。依据该模型提炼出可重用的评测支持系统(Evaluation and Test Supporting System,ETSS)作为系统测试平台,并从接口、管理、通信、同步、实时性和测试实施等几个方面阐述了ETSS的设计思想和原则,及其具有的基本功能。最后,以一个已实现的评测支持系统为例,介绍有关的实现情况。 相似文献
48.
X-machines were proposed by Holcombe as a possible specification language and since then a number of further investigations
have demonstrated that the model is intuitive and easy to use as well as general enough to cater for a wide range of applications.
In particular (generalised) stream X-machines have been found to be extremely useful as a specification method and most of
the theory developed so far has concentrated on this particular class of X-machines. Furthermore, a method for testing systems
specified by stream X-machines exists and is proved to detect all faults of the implementation provided that the system meets
certain initial requirements. However, this method can only be used to generate test sequences from deterministic X-machine
specifications. In this paper we present the theoretical basis for a method for generating test sets from non-deterministic
generalised stream X-machines.
Received November 1999 / Accepted in revised form September 2000 相似文献
49.
50.