全文获取类型
收费全文 | 299812篇 |
免费 | 29037篇 |
国内免费 | 16646篇 |
专业分类
电工技术 | 71092篇 |
技术理论 | 24篇 |
综合类 | 31899篇 |
化学工业 | 14406篇 |
金属工艺 | 9493篇 |
机械仪表 | 21808篇 |
建筑科学 | 21593篇 |
矿业工程 | 10742篇 |
能源动力 | 14705篇 |
轻工业 | 7015篇 |
水利工程 | 8891篇 |
石油天然气 | 8167篇 |
武器工业 | 4719篇 |
无线电 | 33514篇 |
一般工业技术 | 14513篇 |
冶金工业 | 8838篇 |
原子能技术 | 4179篇 |
自动化技术 | 59897篇 |
出版年
2024年 | 465篇 |
2023年 | 2956篇 |
2022年 | 5679篇 |
2021年 | 7286篇 |
2020年 | 8076篇 |
2019年 | 6081篇 |
2018年 | 5569篇 |
2017年 | 7946篇 |
2016年 | 9260篇 |
2015年 | 10773篇 |
2014年 | 19708篇 |
2013年 | 16630篇 |
2012年 | 23077篇 |
2011年 | 24467篇 |
2010年 | 18391篇 |
2009年 | 18400篇 |
2008年 | 18661篇 |
2007年 | 23265篇 |
2006年 | 20773篇 |
2005年 | 18273篇 |
2004年 | 14958篇 |
2003年 | 13143篇 |
2002年 | 10054篇 |
2001年 | 8431篇 |
2000年 | 6856篇 |
1999年 | 5401篇 |
1998年 | 3928篇 |
1997年 | 3152篇 |
1996年 | 2851篇 |
1995年 | 2439篇 |
1994年 | 2034篇 |
1993年 | 1389篇 |
1992年 | 1179篇 |
1991年 | 827篇 |
1990年 | 671篇 |
1989年 | 570篇 |
1988年 | 390篇 |
1987年 | 242篇 |
1986年 | 145篇 |
1985年 | 158篇 |
1984年 | 165篇 |
1983年 | 145篇 |
1982年 | 126篇 |
1981年 | 87篇 |
1980年 | 64篇 |
1979年 | 62篇 |
1978年 | 47篇 |
1977年 | 34篇 |
1976年 | 27篇 |
1959年 | 33篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
81.
82.
83.
基于SSM框架的大坝监测数据管理系统设计 总被引:1,自引:0,他引:1
针对目前大坝安全监测存在数据不能实时计算分析、展示,长期运行产生的大量数据主要靠人工整编且易出错等问题,结合现代信息化技术手段,以Java作为服务开发语言,设计了基于Spring+SpringMVC+Mybatis(SSM)框架的大坝安全监测数据管理平台,用于大坝监测数据的管理和分析,实现数据采集、存储、查询、计算分析、绘图、生成报表报告、实时监控及远程展示等功能,同时亦为监测仪器管理提供了可视化界面,方便仪器管理。结果表明,基于SSM框架的大坝安全监测数据管理系统实时反馈效果好,操作便捷,数据存取性能好、可视化程度高,便于大坝监测数据的管理与实时分析,为大坝安全运行与决策提供支撑。 相似文献
84.
Parallel Multipopulation Differential Evolutionary Particle Swarm Optimization for Voltage and Reactive Power Control 下载免费PDF全文
This paper presents parallel multipopulation differential evolutionary particle swarm optimization (DEEPSO) for voltage and reactive power control (VQC). The problem can be formulated as a mixed integer nonlinear optimization problem and various evolutionary computation techniques have been applied to the problem including PSO, differential evolution (DE), and DEEPSO. Since VQC is one of the online controls, speed‐up of computation is required. Moreover, there is still room for improvement in solution quality. This paper applies parallel multipopulation DEEPSO in order to speed up the calculation and improve solution quality. The proposed method is applied to IEEE 30, 57, and 118 bus systems. The results indicate that the proposed method can realize fast computation and minimize more active power losses than the conventional evolutionary computation techniques. 相似文献
85.
We define the emerging research field of applied data science as the knowledge discovery process in which analytic systems are designed and evaluated to improve the daily practices of domain experts. We investigate adaptive analytic systems as a novel research perspective of the three intertwining aspects within the knowledge discovery process in healthcare: domain and data understanding for physician- and patient-centric healthcare, data preprocessing and modelling using natural language processing and (big) data analytic techniques, and model evaluation and knowledge deployment through information infrastructures. We align these knowledge discovery aspects with the design science research steps of problem investigation, treatment design, and treatment validation, respectively. We note that the adaptive component in healthcare system prototypes may translate to data-driven personalisation aspects including personalised medicine. We explore how applied data science for patient-centric healthcare can thus empower physicians and patients to more effectively and efficiently improve healthcare. We propose meta-algorithmic modelling as a solution-oriented design science research framework in alignment with the knowledge discovery process to address the three key dilemmas in the emerging “post-algorithmic era” of data science: depth versus breadth, selection versus configuration, and accuracy versus transparency. 相似文献
86.
87.
Gerardo Valadez Huerta Johanan Álvarez Jordán Michael Dragon Keno Leites Stephan Kabelac 《International Journal of Hydrogen Energy》2018,43(34):16684-16693
Solid oxide fuel cell (SOFC) systems with anode off-gas recirculation (AGR) and diesel pre-reforming are advantageous because they can operate with the current fuel infrastructure. In the SchIBZ-project, the prototype of such a SOFC system for maritime applications has already been commissioned. In this first paper, we model the system devices to conduct an exergy analysis of this real SOFC plant and validate them with experimental values from experiments in laboratory scale. The results of our simulation agree well with the experimental values. The calculations with the validated results may be closer to the real thermodynamic behavior of such system components than previous literature. 相似文献
88.
89.
AbstractIn recent years, to prevent accidents and disaster are desired by implementing maintenance and management of facilities, such as conducting periodic inspections with appropriate frequency at plants. However, because the dangerous materials such as flammable gas and explosives is used in a plant, and there are many dangerous places in a plant such as high-temperature environment and high places and narrow spaces, it is desirable to use a remote-controlled robot for safety work and short inspections. Against this background, the Disaster Robotics Category-Plant Disaster Prevention Challenge was held in Japan at the World Robot Summit 2018. Our team was ranked 3rd in this competition, because our strategy of ‘inspection and investigation in cooperation with UGV and UAV’ was effective. In this paper, the competition contents of World Robot Summit 2018 and the robot inspection system that we are studying are explained. And what kind of strategy was challenged and result for these given competition tasks by using our robot system are introduced. And the lessons learned such as advantages and issues in UGV and UAV collaboration work at this competition are described for evaluate a robot investigation system for disaster response and inspection work at plants. 相似文献
90.