首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   126篇
  免费   18篇
电工技术   2篇
综合类   2篇
化学工业   16篇
金属工艺   2篇
机械仪表   6篇
建筑科学   12篇
矿业工程   6篇
轻工业   9篇
水利工程   9篇
无线电   9篇
一般工业技术   27篇
冶金工业   9篇
原子能技术   1篇
自动化技术   34篇
  2023年   3篇
  2022年   12篇
  2021年   6篇
  2020年   2篇
  2019年   6篇
  2018年   8篇
  2017年   4篇
  2016年   6篇
  2015年   3篇
  2014年   7篇
  2013年   10篇
  2012年   14篇
  2011年   15篇
  2010年   9篇
  2009年   11篇
  2008年   6篇
  2007年   8篇
  2006年   4篇
  2005年   1篇
  2004年   1篇
  2003年   3篇
  1997年   2篇
  1995年   1篇
  1993年   1篇
  1992年   1篇
排序方式: 共有144条查询结果,搜索用时 171 毫秒
1.
农村水电具有一定的开发优势,但在开发中存在着水能资源管理缺位、部门职责不清、缺乏统一规划和统一调度管理等问题。针对这些问题,从编制流域综合规划、建立和完善水能资源许可制度、加强政府监管力度、实行统一调度、协调水电开发与生态保护的关系等方面提出了管理对策。  相似文献   
2.
Cloud computing services have recently become a ubiquitous service delivery model, covering a wide range of applications from personal file sharing to being an enterprise data warehouse. Building green data center networks providing cloud computing services is an emerging trend in the Information and Communication Technology (ICT) industry, because of Global Warming and the potential GHG emissions resulting from cloud services. As one of the first worldwide initiatives provisioning ICT services entirely based on renewable energy such as solar, wind and hydroelectricity across Canada and around the world, the GreenStar Network (GSN) was developed to dynamically transport user services to be processed in data centers built in proximity to green energy sources, reducing Greenhouse Gas (GHG) emissions of ICT equipments. Regarding the current approach, which focuses mainly in reducing energy consumption at the micro-level through energy efficiency improvements, the overall energy consumption will eventually increase due to the growing demand from new services and users, resulting in an increase in GHG emissions. Based on the cooperation between Mantychore FP7 and the GSN, our approach is, therefore, much broader and more appropriate because it focuses on GHG emission reductions at the macro-level. This article presents some outcomes of our implementation of such a network model, which spans multiple green nodes in Canada, Europe and the USA. The network provides cloud computing services based on dynamic provision of network slices through relocation of virtual data centers.  相似文献   
3.
以设计茶树害虫成虫智能识别应用系统为目的,提出了构建基于图像特征组合智能识别关键技术的三维空间结构(特征组合可分性结构、算法切合度和识别率)研究思想,系统地阐述了三维空间结构的内涵、指标体系、筛选条件、研究模型及实践方法;以尺蛾科典型害虫成虫为实例,认证了研究办法和实现途径的可行性,并对构建智能识别关键技术之三维空间结构知识库的实现路线图进行了展望。  相似文献   
4.
丹江口水库水环境问题分析研究   总被引:3,自引:1,他引:2  
尹炜  史志华  雷阿林 《人民长江》2011,42(13):90-94
为了掌握南水北调中线工程水源地丹江口水库的水质变化情况,依据多年的水质实测资料,对丹江口库区各地的水污染情况进行了全面分析。分析结果表明:按国家标准,丹江口水库水体水质总体良好,符合国家地面水环境质量标准Ⅱ类水标准;但由于库区经济的快速发展,库区水体水质存在恶化趋势,点源污染依然严重,面源污染日趋严重,部分库湾出现富营养化趋势,且存在一些潜在污染风险源。目前,需要加强丹江口水库库区水质的监测,并采取相应污染控制措施,保障未来南水北调工程的水源质量。  相似文献   
5.
Sensor networks are finding significant applications in large scale distributed systems. One of the basic operations in sensor networks is in-network aggregation. Among the various approaches to in-network aggregation, such as gossip and tree, including the hash-based techniques, the tree-based approaches have better performance and energy-saving characteristics. However, sensor networks are highly prone to failures. Numerous techniques suggested in the literature to counteract the effect of failures have not been carefully analyzed. In this paper, we focus on the performance of these tree-based aggregation techniques in the presence of failures. First, we identify a fault model that captures the important failure traits of the system. Then, we analyze the correctness of simple tree aggregation with our fault model. We then use the same fault model to analyze the techniques that utilize redundant trees to improve the variance. The impact of techniques for maintaining the correctness under faults, such as rebuilding or locally fixing the tree, is then studied under the same fault model. We also do the cost-benefit analysis of using the hash-based schemes which are based on FM sketches. We conclude that these fault tolerance techniques for tree aggregation do not necessarily result in substantial improvement in fault tolerance.  相似文献   
6.
The sudden and accidental water pollution response system (SAWPRS) for Yangtze River in central China required to develop a hydrodynamic and transport model, which is readily available and capable of simulating a large river system within GIS environment. This study facilitates such effort by developing a parallel computing method based on digital elevation model (DEM) using overlapping domain decomposition approach (ODDA) and message passing interface (MPI) protocol. The hydrodynamic and transport model was redesigned using finite volume method for hydrodynamic and transport model dispersion, the SIMPLEC method for solving the flow field, and the pressure weighted interpolating method for the flow field modification. This modelling approach was verified in two experiments using different sets of computer clusters. The model output was evaluated against the measured data collected for the year 1998 for Wanzhou, an upstream river segment of Yangtze River. The relative error was found to be less than 10%. The performance of parallel computation was found excellent as evident from the cost efficiency values greater than 0.81 in both experiments and increased computation speed while increasing the number of computer clusters. Overall, the parallel computing modelling system developed here was found to meet all requirements of SAWPRS. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
7.
Recent technological advances in hardware design of the robotic platforms enabled the implementation of various control modalities for improved interactions with humans and unstructured environments. An important application area for the integration of robots with such advanced interaction capabilities is human–robot collaboration. This aspect represents high socio-economic impacts and maintains the sense of purpose of the involved people, as the robots do not completely replace the humans from the work process. The research community’s recent surge of interest in this area has been devoted to the implementation of various methodologies to achieve intuitive and seamless human–robot-environment interactions by incorporating the collaborative partners’ superior capabilities, e.g. human’s cognitive and robot’s physical power generation capacity. In fact, the main purpose of this paper is to review the state-of-the-art on intermediate human–robot interfaces (bi-directional), robot control modalities, system stability, benchmarking and relevant use cases, and to extend views on the required future developments in the realm of human–robot collaboration.  相似文献   
8.
There have been few experience reports from industry on how Model-Driven Engineering (MDE) is applied and what the benefits are. This paper summarizes the experiences of three large industrial participants in a European research project with the objective of developing techniques and tools for applying MDE on the development of large and complex software systems. The participants had varying degrees of previous experience with MDE. They found MDE to be particularly useful for providing abstractions of complex systems at multiple levels or from different viewpoints, for the development of domain-specific models that facilitate communication with non-technical experts, for the purposes of simulation and testing, and for the consumption of models for analysis, such as performance-related decision support and system design improvements. From the industrial perspective, a methodology is considered to be useful and cost-efficient if it is possible to reuse solutions in multiple projects or products. However, developing reusable solutions required extra effort and sometimes had a negative impact on the performance of tools. While the companies identified several benefits of MDE, merging different tools with one another in a seamless development environment required several transformations, which increased the required implementation effort and complexity. Additionally, user-friendliness of tools and the provision of features for managing models of complex systems were identified as crucial for a wider industrial adoption of MDE.  相似文献   
9.
10.
阐述了长江流域水资源利用在全国的战略突出地位及合理开发长江水资源的重要性。分析了以往水资源开发中暴露的重大生态环境问题,论述了构建长江水资源开发与生态保护和谐关系的紧迫性。提出了协调长江开发与保护需要探究的主要研究课题:辨识开发中的生态环境制约问题,研究开发对生态环境的叠加累积效应,探讨生态修复补偿及生态调度措施,研究维系健康长江的管理对策。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号