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131.
城市边缘村庄是城市边缘区动态变化中特殊的地域实体,其城市化进程有着自身特点。该文以郑州城市为例,论述了在当前快速城市化的背景下城边村空间重构与分化的阶段与特征。郑州城边村的演变过程划分为城乡分离、城乡混杂、城乡一体的三个阶段,各阶段村庄发展在用地布局、产业发展、驱动因素、价值与空间形态等方面呈现出不同的特征。在农业产业融合发展的新趋势下,城边村发展不仅需要外在动力,更需要培养内生机制,其核心问题是产业发展问题。最后,建议应培育有特色的村庄产业组群,以产业发展引导村庄空间适当集聚.实现有差别的城乡一体化发展。  相似文献   
132.
This paper provides a means for improving the effectiveness of energy related decision-making during the design phase of a building. A review of the literature and discussions with experts revealed that several approaches for an Integrated Design Process for energy efficient buildings exist. However, most of these approaches are relatively abstract and philosophical in nature, and do not prescribe procedures that enable energy efficient design.This paper attempts to address this gap by proposing a comprehensive design process titled the ‘Integrated Energy-Efficient Building Design Process’ (IEBDP). This process provides a framework based on systems theory that facilitates the integration of various facets of the energy-efficient alternatives selection process. In addition, the proposed framework seeks to integrate state-of-the-art analysis tools and methods, to aid designers in performing holistic building design. Analytical Hierarchy Process (AHP), a multi-attribute decision-making technique is used to resolve conflicts amongst diverging design goals.The proposed IEBDP framework was then used to design an office building, taken as a case study, in the composite climate of New Delhi, India. It was found that considerable energy savings could be achieved by following the IEBDP process. The benefits of this framework vis-a-vis traditional energy efficient design approaches were evaluated by comparing the design done through the IEBDP process with designs submitted by a group of practicing architects. The various designs were evaluated in terms of strategies adopted, the level of exploration as well as design integration, in order to validate the applicability and use of the IEBDP framework.  相似文献   
133.
本文通过对灵山胜境三期工程梵宫建筑及其室内设计的解析,透过专业间的互动融合,有效论证了建筑室内一体化设计的切实可行及低碳高效,并提出了整体化构思、提前化介入、全程化参与的原则,以期对推动设计行业的科学发展有所助益。  相似文献   
134.
A systematic approach to design high-performance feed drive systems   总被引:2,自引:0,他引:2  
A systematic design methodology for the mechatronic system composed of mechanical and control subsystems is proposed to design high-speed and high-precision feed drive systems. Strict mathematical modeling and identification processes of the subsystems are performed in this paper. Parametric studies and circular motion experiments in the xy table are conducted to investigate the influence of interactions on the performance of feed drive systems. Based on analyses of the system performance according to design and operating parameters, a nonlinear constrained optimization problem including the relevant subsystem parameters of the feed drive system is formulated. The multi-objective optimization procedure and normalization technique are introduced in the design process. A Pareto optimum solution set is applied to investigate the relationships between objective functions. The effectiveness of the proposed design methodology is verified through numerical case studies.  相似文献   
135.
在综合考虑制造/再制造物流系统的分区,选址和运输问题,以及运输和设施建设成本的规模经济效应的基础上,建立了两阶段规划模型,用来确定客户分区,选址方案,配送、回收的物流分配和运输路径,使运营周期内的净收益最大.最后通过一个算例验证了模型和算法的有效性.  相似文献   
136.
将纳扎洛夫水驱曲线法和Logistic预测模型有机结合,提出了一种预测水驱油田开发指标的综合模型。克服了两种方法在动态预测上的不足,能够方便地预测历年的开发指标,应用表明,该模型的预测结果与实际值吻合程度较高。  相似文献   
137.
濮城油田文51断块是一个典型的多油层非均质复杂断块油藏,长期注水开发造成井况损坏严重,注采井网遭到破坏,剩余油集中在井况损坏区、断层高部位、注水切割区及河道砂体注入水流线未波及的井间滞留区。剩余油的挖潜依靠多元化配套技术,完善注采井网,扩大注水波及体积,提高水驱控制储量和动用储量,从而提高区块采收率。  相似文献   
138.
An integrated model is established to simulate both hydrological processes and accompanied pollutant transfer processes in the Yellow River Basin. The model couples distributed hydrological model WEP-L (Water and Energy transfer Processes in Large river basins) and a newly developed water quality module which includes simulation functions of soil erosion and sediment transport, and non-point and point sources transfer to rivers. To overcome the defects of traditional water quality assessment, two aspects of improvement are conducted. One is the improvement of the traditional characteristic channel length approach, i.e., the product of multiplying channel length by lateral section area is selected as a new assessment criterion to reflect the different contributions of small channels and big ones, thus making the assessment results more objective. The other is the suggestion of integrated assessment approach for both water at channel lateral sections and water generated in sub-basins. The assessment results in the Yellow River Basin illustrate: (1) the improved characteristic channel length approach shows rivers of water quality worse than Class III account for 75% whilst the traditional approach give a result of 45%, implying that the actual status of water quality is worse than the traditional understanding; (2) the quality of water generated in sub-basins is much better than the quality of water at channel lateral sections. The assessment results describe the status of water resources quantity and quality from different points of view and thus provide valuable information for the water resources development and management in the basin.  相似文献   
139.
针对人工检测排水管道存在的管道直径小及易燃、易爆等问题,设计一种基于集成阀控制的管道机器人。集成阀具有密封防爆、扩展性强等优点。该机器人采用气动动力系统、蠕动行走方式,能在一定范围内的变径管道中行走并转弯,完成管道清洗、检测等工作。控制系统采用下位机操作,通过缆绳到上位PC机集中控制。所设计的机器人具有安全防爆、动力保障性强、故障机器人回收维修方便、性价比高等优点。  相似文献   
140.
A roadmap towards intelligent net zero- and positive-energy buildings   总被引:1,自引:0,他引:1  
Buildings nowadays are increasingly expected to meet higher and more complex performance requirements: they should be sustainable; use zero-net energy; foster a healthy and comfortable environment for the occupants; be grid-friendly, yet economical to build and maintain. The essential ingredients for the successful development and operation of net zero- and positive-energy buildings (NZEB/PEB) are: thermal simulation models, that are accurate representations of the building and its subsystems; sensors, actuators, and user interfaces to facilitate communication between the physical and simulation layers; and finally, integrated control and optimization tools of sufficient generality that using the sensor inputs and the thermal models can take intelligent decisions, in almost real-time, regarding the operation of the building and its subsystems. To this end the aim of the present paper is to present a review on the technological developments in each of the essential ingredients that may support the future integration of successful NZEB/PEB, i.e. accurate simulation models, sensors and actuators and last but not least the building optimization and control. The integration of the user is an integral part in the dynamic behavior of the system, and this role has to be taken into account. Future prospects and research trends are discussed.  相似文献   
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