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991.
3D video for tele-medicine applications is gradually gaining momentum since the 3D technology can provide precise location information. However, the weak link for 3D video streaming is the necessary wireless link of the communication system. Neglecting the wireless impairments can severely degrade the performance of 3D video streaming that communicates complex critical medical data. In this paper, we propose systematic methodology for ensuring high performance of the 3D medical video streaming system. First, we present a recursive end-to-end distortion estimation approach for MVC (multiview video coding)-based 3D video streaming over error-prone networks by considering the 3D inter-view prediction. Then, based on the previous model, we develop a cross-layer optimization scheme that considers the LTE wireless physical layer (PHY). In this optimization, the authentication requirements of 3D medical video are also taken into account. The proposed cross-layer optimization approach jointly controls and manages the authentication, video coding quantization of 3D video, and the modulation and channel coding scheme (MCS) of the LTE wireless PHY to minimize the end-to-end video distortion. Experimental results show that the proposed approach can provide superior 3D medical video streaming performance in terms of peak signal-to-noise ratio (PSNR) when compared to state-of-the-art approaches that include joint source-channel optimized streaming with multi-path hash-chaining based-authentication, and also conventional video streaming with single path hash-chaining-based authentication. 相似文献
992.
In this paper we report on an unclear effect in the IV characteristics of organic light emitting diodes (OLEDs). When the thickness of the emitter layer based on a modified phenyl carbozole triplet host material (TH) in the device is increased, a significant shift of the onset voltage to higher values can be noticed. The voltage shift is not observed if the TH is substituted by an isomer with only minor variation of the molecular structure. In a previous publication we could already show that an electric interface field is necessary to describe the onset voltage behaviour. To find the origin of this interface field in the present publication the two isomers are characterized and the band alignment at the interfaces to the emitter layer is investigated using photoelectron spectroscopy. The interface energy diagrams have been measured on stepwise prepared model interfaces. A further simplification of the bipolar to a hole only device stack proofs, that band bending at the hole injecting interface to the TH layer is the origin of the interface field. In contrast an entire flat band situation is measured in case of the device using the other isomer showing no onset voltage shift. 相似文献
993.
No longer is it appropriate to evaluate processes for economic feasibility alone; social benefits and environmental impacts must also be considered. This work develops a multi criteria systematic framework for optimum process design with sustainability considerations and addresses a major challenge in process design as engineers will now be able to design for multiple criteria, specifically sustainability concerns. A novel multi objective optimization algorithm capable of handling a multitude of objectives in mixed integer nonlinear search space and a novel decision making methodology are integrated with a sequential modular process simulator to optimize processes with a multitude of objectives rigorously and efficiently. The application of this research extends well beyond sustainability considerations to the very vast area of optimum design with multi criteria. The application of the proposed framework is demonstrated through a case study for process retrofit of Dimethyl Ether production plant. 相似文献
994.
In this paper, we propose a multi-period mixed-integer linear programming model for optimal enterprise-level planning of industrial gas operations. The objective is to minimize the total cost of production and distribution of liquid products by coordinating production decisions at multiple plants and distribution decisions at multiple depots. Production decisions include production modes and rates that determine power consumption. Distribution decisions involve source, destination, quantity, route, and time of each truck delivery. The selection of routes is a critical factor of the distribution cost. The main goal of this contribution is to assess the benefits of optimal coordination of production and distribution. The proposed methodology has been tested on small, medium, and large size examples. The results show that significant benefits can be obtained with higher coordination among plants/depots in order to fulfill a common set of shared customer demands. The application to real industrial size test cases is also discussed. 相似文献
995.
准确测定PTMEG中微量甲醇钠含量是生产优质PTMEG产品的重要保证,而传统测定方法由于未能完全游离甲醇钠,往往致使检测值偏低。为此,对PTMEG中微量甲醇钠含量测定方法进行了系统优化,分别考察了溶剂溶解性、滴定液浓度、溶剂量、样品质量对甲醇钠检出量的影响。结果表明:选用50.00 mL无水甲醇、5.0 g PTMEG样品及0.005 0 mol/L HCl标准滴定液进行滴定时,甲醇钠检出量达到最大,测定结果最接近真实值,且方法准确可靠。 相似文献
996.
997.
998.
《Thin》2014
The objective of this paper is to present constrained optimization results for a cold-formed steel (CFS) cross-section shape with maximum axial capacity. In the authors׳ previous work unconstrained shape optimization was performed via stochastic search and gradient-based algorithms. Unconstrained shape optimizations produced a significant capacity increase, more than 140%, above standard CFS cross-sections, but many of the solutions are highly unconventional and have potential limitations both with respect to end use (e.g. attaching boards for walls and floors) and cost of manufacturing. Column capacity is determined using the Direct Strength Method (DSM) which requires inputs for the local, distortional and global critical buckling loads. These critical loads are obtained using the finite strip method, as implemented in the open source software CUFSM, which allows essentially any potential cross-section to be evaluated. To advance the applicability of the optimized results, end-use constraints and manufacturing constraints on the number of rollers employed in forming were both successfully incorporated in the shape optimization presented in this paper, resulting in optimized cross-sections that are more practical and economical with only marginally decreased capacity (usually less than 10%) from the earlier unconstrained optimized solutions. The constraints are implemented within a simulated annealing (SA) algorithm for the optimization. Optimized sections from multiple runs show uniformity, partially indicating the robustness of the final optimized shapes. The implemented constrained shape optimization provides a thorough search with high computational efficiency. The optimized cross-sections from this research provide promising potential shapes for the development of new commercial product families, and the member-level optimization methodology can also be integrated into building optimization in the future. 相似文献
999.
通过对生产数据的选择和处理、对品位与燃料比线性关系的定量分析,依据铁矿石品位综合评价法,确定了SiO2含量和品位的关系;在此基础上,进一步通过对炉料性价比的测算,提出了优化炉料结构的建议。建议指出了低品质的炉料结构优化路线不适合长期的集中选用,只能短期、间断性、少量地掺插使用;同时也给出了合理的炉料结构的优化措施。 相似文献
1000.
为了研究巷道爆破掘进过程中掏槽空腔直径对崩落孔爆破效果的影响,运用ANSYS/LS-DYNA对掏槽空腔附近崩落孔的爆破效果进行模拟计算。建立崩落孔孔距A为450 mm、崩落孔抵抗线L和掏槽空腔直径B均为400 mm的初始模型,并以该模型为基础,保持L和A不变,逐步增大B建立额外4个模型。计算并绘制崩落区岩石的塑性应变图,分析得出:随着掏槽空腔直径的增大,岩石塑性应变区域开始增大,爆破效果逐渐改善,当B/L=2时炮孔之间的塑性应变区域连通,掏槽空腔直径对爆破的改善效果达到最优水平;提取掏槽空腔外一系列监测点的拉、压应力值进行分析后得到相同的结论。研究结果可为巷道爆破孔网参数设计提供理论依据和技术参考。 相似文献