全文获取类型
收费全文 | 6605篇 |
免费 | 221篇 |
国内免费 | 141篇 |
专业分类
电工技术 | 357篇 |
综合类 | 202篇 |
化学工业 | 369篇 |
金属工艺 | 326篇 |
机械仪表 | 844篇 |
建筑科学 | 366篇 |
矿业工程 | 133篇 |
能源动力 | 269篇 |
轻工业 | 286篇 |
水利工程 | 57篇 |
石油天然气 | 158篇 |
武器工业 | 107篇 |
无线电 | 697篇 |
一般工业技术 | 451篇 |
冶金工业 | 287篇 |
原子能技术 | 188篇 |
自动化技术 | 1870篇 |
出版年
2024年 | 11篇 |
2023年 | 37篇 |
2022年 | 67篇 |
2021年 | 133篇 |
2020年 | 112篇 |
2019年 | 63篇 |
2018年 | 70篇 |
2017年 | 124篇 |
2016年 | 142篇 |
2015年 | 177篇 |
2014年 | 306篇 |
2013年 | 338篇 |
2012年 | 316篇 |
2011年 | 406篇 |
2010年 | 312篇 |
2009年 | 311篇 |
2008年 | 314篇 |
2007年 | 407篇 |
2006年 | 410篇 |
2005年 | 386篇 |
2004年 | 339篇 |
2003年 | 336篇 |
2002年 | 279篇 |
2001年 | 210篇 |
2000年 | 218篇 |
1999年 | 203篇 |
1998年 | 161篇 |
1997年 | 150篇 |
1996年 | 101篇 |
1995年 | 71篇 |
1994年 | 77篇 |
1993年 | 57篇 |
1992年 | 50篇 |
1991年 | 38篇 |
1990年 | 46篇 |
1989年 | 20篇 |
1988年 | 17篇 |
1987年 | 15篇 |
1986年 | 5篇 |
1985年 | 11篇 |
1984年 | 10篇 |
1982年 | 7篇 |
1981年 | 8篇 |
1966年 | 5篇 |
1965年 | 9篇 |
1963年 | 5篇 |
1959年 | 7篇 |
1958年 | 10篇 |
1956年 | 8篇 |
1955年 | 13篇 |
排序方式: 共有6967条查询结果,搜索用时 15 毫秒
81.
82.
伍治平 《电脑编程技巧与维护》2008,(9):105-106
随着项目的复杂度日趋复杂,设计及实现的重构日趋频繁。项目对质量管理的要求也越来越高。项目质量管理所涉及的内容是多方面的,本文根据实践积累,结合作者所管理项目的质量提升过程,讲述了几种项目过程质量管理方法的组合应用,并对项目质量管理工作的一些心得及经验进行了总结。 相似文献
83.
基于C#的打字测试软件研究与开发 总被引:1,自引:0,他引:1
信息时代下,掌握和熟练操作计算机成为社会对现代人的基本要求.文字录入的快慢在一定程度上影响着工作效率.开发一套较完善的打字测试软件来公平公正的考核学生的打字水平成为必要.基于C#语言开发的打字测试软件具有界面简捷、组织测试方便、评分精确合理、成绩回收容易、统计成绩方便.学生水平分析准确等优点. 相似文献
84.
日益复杂的数字系统设计,须由各种专业的设计人员分工完成。他们之间需要一种描述系统的“共同语言”来沟通,这对于提高设计质量、缩短设计周期、减少设计费用具有积极意义。Petri网十分适合担任这一“共同语言”的角色。文章给出了数字电路测试仪器中的硬件设计的部分实例。 相似文献
85.
86.
In the context of increasingly competitive intelligent manufacturing, the multi-load Automated guided vehicles (AGVs) based Automated Storage and Retrieval System (AS/RS) has been of particular interest, as reductions in the number of AGVs required can significantly decrease potential congestions and increase the system effectiveness. In comparison with the single-load AGVs system, more difficult and critical issue of scheduling multi-load AGVs to automate storage/retrieval missions and to maximize economic benefits remains unresolved. Therefore, we propose a task scheduling optimization method for multi-load AGVs-based systems, with which, the objectives of least number of occupied AGVs, shortest travel time and minimum conflicts can be met simultaneously. The experiments are conducted in various scenarios, and verify that our work can use fewer AGVs to optimize tasks delivery, which enables the AS/RS stakeholders to reach win-win results for system performance and AGVs investment, thus maximizing economic benefit. 相似文献
87.
The automatic generation of test data is a key step in realizing automated testing. Most automated testing tools for unit testing only provide test case execution drivers and cannot generate test data that meets coverage requirements. This paper presents an improved Whale Genetic Algorithm for generating test data required for unit testing MC/DC coverage. The proposed algorithm introduces an elite retention strategy to avoid the genetic algorithm from falling into iterative degradation. At the same time, the mutation threshold of the whale algorithm is introduced to balance the global exploration and local search capabilities of the genetic algorithm. The threshold is dynamically adjusted according to the diversity and evolution stage of current population, which positively guides the evolution of the population. Finally, an improved crossover strategy is proposed to accelerate the convergence of the algorithm. The improved whale genetic algorithm is compared with genetic algorithm, whale algorithm and particle swarm algorithm on two benchmark programs. The results show that the proposed algorithm is faster for test data generation than comparison methods and can provide better coverage with fewer evaluations, and has great advantages in generating test data. 相似文献
88.
Both unit and integration testing are incredibly crucial for almost any software application because each of them operates a distinct process to examine the product. Due to resource constraints, when software is subjected to modifications, the drastic increase in the count of test cases forces the testers to opt for a test optimization strategy. One such strategy is test case prioritization (TCP). Existing works have propounded various methodologies that re-order the system-level test cases intending to boost either the fault detection capabilities or the coverage efficacy at the earliest. Nonetheless, singularity in objective functions and the lack of dissimilitude among the re-ordered test sequences have degraded the cogency of their approaches. Considering such gaps and scenarios when the meteoric and continuous updations in the software make the intensive unit and integration testing process more fragile, this study has introduced a memetics-inspired methodology for TCP. The proposed structure is first embedded with diverse parameters, and then traditional steps of the shuffled-frog-leaping approach (SFLA) are followed to prioritize the test cases at unit and integration levels. On 5 standard test functions, a comparative analysis is conducted between the established algorithms and the proposed approach, where the latter enhances the coverage rate and fault detection of re-ordered test sets. Investigation results related to the mean average percentage of fault detection (APFD) confirmed that the proposed approach exceeds the memetic, basic multi-walk, PSO, and optimized multi-walk by 21.7%, 13.99%, 12.24%, and 11.51%, respectively. 相似文献
89.
A variety of stakeholders have put forth automated vehicle (AV) deployment timeline predictions over the past decade. To synthesize these predictions, we performed a systematic literature review of past and current AV deployment timeline predictions in the United States from different stakeholder groups, including private stakeholders, government organizations, and research organizations. Our analysis revealed that none of the AV mass deployment timelines from any stakeholder group have been met. It also shows discrepancies between timelines put forth by private and public stakeholders, with the private sector being more optimistic in their predictions. Accurate timelines are needed so regulators are able to create appropriate public policies and comprehensive budgets, and private stakeholders can make better informed decisions. More specifically, the mass deployment of AVs is anticipated to affect many transportation-related jobs which reinforces the importance of accurate AV deployment timelines to prepare the workers who may be displaced and for the development of workforce education and training initiatives. 相似文献
90.