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1.
风电和光伏发电具有间歇性和随机性,为了降低在多源联合发电系统中的弃风弃光率,采用含氢储能系统和火电机组配合来平滑风电和光电机组出力。文中以系统运行成本最小和弃电惩罚成本最小为目标,以系统功率平衡、火电机组出力和爬坡、热备用、风电和光电出力及储能系统储氢罐容量、电解槽和燃料电池功率等为约束条件构建了多源联合发电系统日前调度模型。通过YALMIP工具箱对模型进行编程,并调用CPLEX对编写的程序进行求解。对含有风电、光电、火电机组以及储能系统的多源联合发电系统进行算例分析,通过对比有无储能系统的弃风弃光量和系统总运行成本,证明了含氢储能系统可以有效降低系统的弃风弃光率,并提高系统的经济性。 相似文献
2.
《Soils and Foundations》2022,62(4):101187
Assessments of the liquefaction resistance of clean sand still involve considerable uncertainties, which are a current research topic in the field of soil liquefaction. The factors considered and discussed in this study include the loading history, degree of saturation, and partial drainage. The effects of each of these factors on pore pressure generation and liquefaction resistance have been studied for decades in the laboratory, and empirical relationships have been derived. In this paper, an attempt is made to explain these effects using the unique index of volumetric strain. A pore pressure generation model is developed which is similar to that of Martin et al. (1975), but based on stress-controlled triaxial tests. The model is verified through comparisons of its results with those of laboratory tests. It is confirmed that the plastic volumetric strain that has accumulated in sand, either by drained or undrained cyclic loading, dominates the increase in the liquefaction resistance of the sand. However, the plastic volumetric strain caused by overconsolidation is less effective in reducing the volumetric strain potential for subsequent cyclic shearing, thus enhancing its resistance to liquefaction. The model provides a better understanding of the physical processes leading to the liquefaction of saturated and unsaturated sand with and without stress history. 相似文献
3.
《Geotextiles and Geomembranes》2022,50(3):535-544
Soil column is often investigated in the improvement of dredged slurries. Different from the smear zone, the soil column forms gradually and has extremely low permeability. This study presents an analytical solution for soil consolidation considering the increasing radius of the soil column and time-dependent discharge capacity. Based on the solution, the influence of the radius' increase on the consolidation behavior is found significant when the soil column has low permeability and large final radius, and the increase of formation time can lead to the increase of consolidation speed and final consolidation degree. 相似文献
4.
The aim of this paper is to measure and benchmark the environmental performance of Portuguese utilities jointly active in the three sectors of water supply, wastewater collection and solid waste management. To do so, we suggest the use of a traditional (optimistic) directional distance Benefit of the Doubt index. We complement the analysis by considering also the pessimistic version of the proposed BoD and by implementing a robust and conditional approach. The obtained results show that there is space for improvement in the pressure balance of these utilities, especially for small and very large units, mostly operating in urban areas. 相似文献
5.
目前,各国结构用玻璃设计标准相对其他传统建筑材料仍欠成熟,且其中关于玻璃构件承载性能的设计方法也存在较大的差异。为此,对比分析了我国与美、澳、英、欧等国家和地区结构用玻璃设计标准在适用范围、设计理论以及构件承载性能设计模型的异同。结果表明:JGJ 113—2015《建筑玻璃应用技术规程》中对结构用玻璃设计标准的适用范围和设计理论有待进一步扩大和完善;对夹层玻璃的有效厚度计算偏于保守;对玻璃的鲁棒性设计模型缺失问题亟待解决。此外,针对结构用玻璃的特性和需求,对设计标准中应进一步考虑的问题提出了建议,包括玻璃构件连接节点的应力集中、环境荷载耦合劣化以及玻璃结构在极端荷载作用下的安全等。 相似文献
6.
为研究高强钢外伸端板加劲螺栓连接节点的抗震性能和设计方法,基于EC3规范组件法和同步塑性设计理念,设计了3种不同屈服机制的Q690高强钢外伸端板加劲螺栓连接节点,通过循环加载试验研究了节点的破坏模式、刚度和承载力、耗能能力以及应变分布规律等,进一步验证了节点能力设计计算模型的有效性。研究结果表明:高强钢外伸端板加劲螺栓连接超强节点的能量耗散区主要集中在梁翼缘削弱区域,等强节点的能量耗散区主要分布于端板连接处以及梁翼缘削弱区域,两种节点均属于延性破坏模式;欠强节点仅依靠端板与梁翼缘间的焊缝裂纹不断扩展和闭合以及有限的端板塑性变形耗散地震能量,属于脆性破坏模式;高强钢外伸端板加劲连接节点的破坏模式、屈服机制以及耗能能力等均与节点的能力设计参数密切相关,基于EC3规范组件法的高强钢外伸端板加劲连接节点能力设计计算模型,可较准确地预测节点的破坏模式,但能力设计参数的合理取值有待继续研究。 相似文献
7.
对国产12.9级高强度螺栓的工程力学性能进行全面测定,为其在建筑结构中的设计和应用以及相关标准的制定和修改提供试验依据。分别通过紧固试验、抗拉试验和剪切试验对不同品牌(A、B、C)和规格(M16、M20和M24)的各72套12.9级高强度螺栓连接副的扭矩系数、抗拉强度和剪切强度进行测定;通过抗滑移试验对72个由B品牌M20螺栓连接的、各采用3种方式处理(喷砂、抛丸和钢丝除锈)的Q235B、Q355B、Q420B连接板表面的连接接头的抗滑移系数进行测定;对5个A品牌M20螺栓制成的材性试样进行拉伸试验获得应力-应变曲线。对试验数据进行正态分布检验并根据统计结果给出12.9级高强度螺栓的扭矩系数、抗拉强度和剪切强度的设计参考值,将抗滑移系数和相关规范中给出的相应值(规范值)进行比较并分析测值较低的原因,建立螺栓材料的非线性和多折线应力-应变本构模型并验证模型精度。研究结果表明:国产12.9级高强度螺栓的扭矩系数和抗拉强度均符合性能标准,剪切强度和抗拉强度设计建议值的比值(0.49)高于二者规范值的比值(0.3);抗滑移系数低于规范值的结果有待进一步研究,原因是接触面的粗糙度不足;非线性模型和多折线模型均能较好地拟合12.9级高强度螺栓材料的单向拉伸应力-应变曲线。 相似文献
8.
当前方法对运行电厂设备进行监测时存在监测运行时间长、聚类效果差和监测效果差的问题,为此提出物联网技术在电厂设备运行监测系统中的应用方法。对电力数据的状态进行评估聚类,生成电厂设备状态信息类别,基于隶属度最大原则生成电力状态信息集;在物联网技术的基础上计算节点间的欧氏距离,并采用横向近似的方法分析电力情况,最终经过对数据点的修正,确认出设备的异常数据点,实现电厂设备运行监测。实验结果表明,所提方法的监测运行时短、聚类效果好、监测效果好,以及监测结果平均误差小。 相似文献
9.
Digital twin (DT) has garnered attention in both industry and academia. With advances in big data and internet of things (IoTs) technologies, the infrastructure for DT implementation is becoming more readily available. As an emerging technology, there are both potential and challenges. DT is a promising methodology to leverage the modern data explosion to aid engineers, managers, healthcare experts and politicians in managing production lines, patient health and smart cities by providing a comprehensive and high fidelity monitoring, prognostics and diagnostics tools. New research and surveys into the topic are published regularly, as interest in this technology is high although there is a lack of standardization to the definition of a DT. Due to the large amount of information present in a DT system and the dual cyber and physical nature of a DT, augmented reality (AR) is a suitable technology for data visualization and interaction with DTs. This paper seeks to classify different types of DT implementations that have been reported, highlights some researches that have used AR as data visualization tool in DT, and examines the more recent approaches to solve outstanding challenges in DT and the integration of DT and AR.The full text can be downloaded at https://link.springer.com/article/10.1007/s40436-021-00375-w 相似文献
10.
Bogdan DORNEANU Sushen ZHANG Hang RUAN Mohamed HESHMAT Ruijuan CHEN Vassilios S. VASSILIADIS Harvey ARELLANO-GARCIA 《工程管理前沿(英文版)》2022,9(4):623
Industry 4.0 aims to transform chemical and biochemical processes into intelligent systems via the integration of digital components with the actual physical units involved. This process can be thought of as addition of a central nervous system with a sensing and control monitoring of components and regulating the performance of the individual physical assets (processes, units, etc.) involved. Established technologies central to the digital integrating components are smart sensing, mobile communication, Internet of Things, modelling and simulation, advanced data processing, storage and analysis, advanced process control, artificial intelligence and machine learning, cloud computing, and virtual and augmented reality. An essential element to this transformation is the exploitation of large amounts of historical process data and large volumes of data generated in real-time by smart sensors widely used in industry. Exploitation of the information contained in these data requires the use of advanced machine learning and artificial intelligence technologies integrated with more traditional modelling techniques. The purpose of this paper is twofold: a) to present the state-of-the-art of the aforementioned technologies, and b) to present a strategic plan for their integration toward the goal of an autonomous smart plant capable of self-adaption and self-regulation for short- and long-term production management. 相似文献