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1.
An understanding of the similar and divergent metrics and methodologies underlying open government data benchmarks can reduce the risks of the potential misinterpretation and misuse of benchmarking outcomes by policymakers, politicians, and researchers. Hence, this study aims to compare the metrics and methodologies used to measure, benchmark, and rank governments' progress in open government data initiatives. Using a critical meta-analysis approach, we compare nine benchmarks with reference to meta-data, meta-methods, and meta-theories. This study finds that both existing open government data benchmarks and academic open data progress models use a great variety of metrics and methodologies, although open data impact is not usually measured. While several benchmarks’ methods have changed over time, and variables measured have been adjusted, we did not identify a similar pattern for academic open data progress models. This study contributes to open data research in three ways: 1) it reveals the strengths and weaknesses of existing open government data benchmarks and academic open data progress models; 2) it reveals that the selected open data benchmarks employ relatively similar measures as the theoretical open data progress models; and 3) it provides an updated overview of the different approaches used to measure open government data initiatives’ progress. Finally, this study offers two practical contributions: 1) it provides the basis for combining the strengths of benchmarks to create more comprehensive approaches for measuring governments’ progress in open data initiatives; and 2) it explains why particular countries are ranked in a certain way. This information is essential for governments and researchers to identify and propose effective measures to improve their open data initiatives.  相似文献   
2.
程海涛  申献双 《塑料工业》2020,48(2):1-8,63
针对高密度聚乙烯(HDPE)力学性能、阻燃性、热稳定性、结晶性能等改性进行了评述。结合现有研究以及实验经验,对HDPE改性研究方向进行了展望。  相似文献   
3.
Direct methanol fuel cells (DMFC), among the most suited and prospective alternatives for portable electronics, have lately been treated with nanotechnology. DMFCs may be able to remedy the energy security issue by having low operating temperatures, high conversion efficiencies, and minimal emission levels. Though, slow reaction kinetics are a significant restriction of DMFC, lowering efficiency and energy output. Nowadays, research is more focused on fundamental studies that are studying the factors that can improve the capacity and activity of catalysts. In DMFC, among the most widely explored catalysts are platinum and ruthenium which are enhanced in nature by the presence of supporting materials such as nanocarbons and metal oxides. As a result, this research sheds light on nanocatalyst development for DMFCs based on Platinum noble metal. To summarize, this research focuses on the structure of nanocatalysts, as well as support materials for nanocatalysts that can be 3D, 2D, 1D, or 0D. The support material described is made up of CNT, CNF, and CNW, which are the most extensively used because they improve the performance of catalysts in DMFCs. In addition, cost estimations for fuel cell technology are emphasized to show the technology's status and requirements. Finally, challenges to nanocatalyst development have been recognized, as well as future prospects, as recommendations for more innovative future research.  相似文献   
4.
王富臣  钱小玲 《华中建筑》2002,20(1):49-50,56
科学的发展与技术的进步是城市空间演变过程中最为活跃的影响因素。科学的发展,在改变着人们对世界的认识同时,引发了规划设计观念的更新。技术的进步,在促使城市化水平提高的过程中,促使了城市空间的重组。在科学的新观念和技术的新方法的共同作用下,城市形态进行着持续的演化。  相似文献   
5.
Accurate and rapid assessment of the as-built status on any construction site provides the opportunity to understand the current performance of a project easily and quickly. Rapid project assessment further identifies discrepancies between the as-built and as-planned progress, and facilitates decision making on the necessary remedial actions. Currently, manual visual observations and surveying are the most dominant data capturing techniques but they are time-consuming, error-prone, and infrequent, making quick and reliable decision-making difficult. Therefore, research on new approaches that allow automatic recognition of as-built performance and visualization of construction progress is essential. This paper presents and compares two methods for obtaining point cloud models for detection and visualization of as-built status for construction projects: (1) A new method of automated image-based reconstruction and modeling of the as-built project status using unordered daily construction photo collections through analysis of Structure from Motion (SfM); (2) 3D laser scanning and analysis of the as-built dense point cloud models. These approaches provide robust means for recognition of progress, productivity, and quality on a construction site. In this paper, an overview of the newly developed automated image-based reconstruction approach and exclusive features which distinct it from other image-based or conventional photogrammetric techniques is presented. Subsequently the terrestrial laser scanning approach carried out for reconstruction and comparison of as-built scenes is presented. Finally the accuracy and usability of both of these techniques for metric reconstruction, automated production of point cloud models, 3D CAD shape modeling, and as-built visualizations is evaluated and compared on eight different case studies. It is shown that for precise defect detection or alignment tasks, image-based point cloud models may not be as accurate and dense as laser scanners' point cloud models. Nonetheless image-based point cloud models provide an opportunity to extract as-built semantic information (i.e., progress, productivity, quality and safety) through the content of the images, are easy to use, and do not need add burden on the project management teams by requiring expertise for data collection or analysis. Finally image-based reconstruction automatically provides photo alignment with point cloud models and enables image-based renderings which can remarkably impact automated performance monitoring and as-built visualizations.  相似文献   
6.
郑志锋 《福建建筑》2007,(6):100-101
本文主要从施工项目管理的组织机构、质量管理、进度计划、安全生产和文明施工等方面给以详尽的阐述,深入分析,提出个人对施工项目管理工作的认识。  相似文献   
7.
简介影响30000 m3/h空分设备项目进度控制的主要问题,介绍为实现项目进度的控制目标,而采取的优化项目组织形式、完善项目计划管理措施、引入项目考核机制和加强项目团队建设等具体措施。  相似文献   
8.
在分析公共云服务认证于市场的意义,总结全球已成功开展公共云服务认证的国家经验的基础上,从3个方面介绍了目前公共云服务认证的研究成果,一是分析公共云服务认证的意义;二是总结全球已成功开展公共云服务认证国家的经验;三是我国公共云服务认证进展情况并提出发展建议。  相似文献   
9.
刘朝艳 《塑料工业》2020,48(4):1-14
收集了2018年7月~2019年6月世界工程塑料和特种工程塑料工业的相关资料,介绍了2018~2019年世界工程塑料和特种工程塑料工业的发展情况,按工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯)和特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮、聚芳砜、聚邻苯二甲酰胺)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍。  相似文献   
10.
分析近红外在农业领域应用的特殊性,分析近红外分析过程中影响模型性能的若干因素,讨论近红外分析准确度的评价方法,预测标准差SEP不宜作为近红外分析性能的指标性参数,提出近红外分析在农业应用中值得重视的研究方向。  相似文献   
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