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In this paper, we present a performance analysis of large-scale multi-input multi-output (MIMO) systems for wireless backhaul networks. We focus on fully connected N nodes in a wireless meshed and multi-hop network topology. We also consider a large number of antennas at both the receiver and transmitter. We investigate the transmission schemes to support fully connected N nodes for half-duplex and full-duplex transmission, analyze the achievable ergodic sum rate among N nodes, and propose a closed-form expression of the achievable ergodic sum rate for each scheme. Furthermore, we present numerical evaluation results and compare the resuts with closed-form expressions. 相似文献
3.
Vida Janbazi Mahnaz Hashemi 《International Journal of Adaptive Control and Signal Processing》2021,35(2):285-309
This article presents an adaptive neural compensation scheme for a class of large-scale time delay nonlinear systems in the presence of unknown dead zone, external disturbances, and actuator faults. In this article, the quadratic Lyapunov–Krasovskii functionals are introduced to tackle the system delays. The unknown functions of the system are estimated by using radial basis function neural networks. Furthermore, a disturbance observer is developed to approximate the external disturbances. The proposed adaptive neural compensation control method is constructed by utilizing a backstepping technique. The boundedness of all the closed-loop signals is guaranteed via Lyapunov analysis and the tracking errors are proved to converge to a small neighborhood of the origin. Simulation results are provided to illustrate the effectiveness of the proposed control approach. 相似文献
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马尔可夫聚类算法(MCL)是在大规模生物网络中寻找模块的一个有效方法,能够挖掘网络结构和功能影响力较大的模块。算法涉及到大规模矩阵计算,因此复杂度可达立方阶次。针对复杂度高的问题,提出了基于消息传递接口(MPI)的并行化马尔可夫聚类算法以提高算法的计算性能。首先,生物网络转化成邻接矩阵;然后,根据算法的特性,按照矩阵的规模判断并重新生成新矩阵以处理非平方倍数矩阵的计算;其次,并行计算通过按块分配的方式能够有效地实现任意规模矩阵的运算;最后,循环并行计算直至收敛,得到网络聚类结果。通过模拟网络和真实生物网络数据集的实验结果表明,与全块集体式通信(FCC)并行方法相比,平均并行效率提升了10个百分点以上,因此可以将该优化算法应用在不同类型的大规模生物网络中。 相似文献
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The consensus-reaching process (CRP) to achieve higher unanimity and ensure common agreement before deriving a final decision has become an important procedure in group decision-making problems. The demand for high-quality decision results has motivated the development of large-scale group decision-making (LGDM). In such cases, the issue of minority opinion has gained awareness due to the related effects on enhancing consensus and decision quality. A minority opinion cannot exert an effect unless the majority attach importance to whether that opinion is supported or not. To reflect the effect of minority opinions on consensus, this paper establishes a LGDM framework with an objective and interactive-information-based feedback mechanism for the CRP. Given the natural forms of human expression, multi-granular linguistic information and a 2-tuple linguistic model are used. First, initial weights are objectively assigned to decision-makers (DMs) to weaken the impact of the majority. Subsequently, a non-support degree function is newly defined to reflect the extent to which other DMs dissent from a minority opinion. More importantly, feedback rules are constructed to make corresponding adjustments to the powers of discourse among all DMs in the attempt to reach consensus. Finally, the proposed three-phase LGDM framework is applied to new product development (NPD), and simulation experiments are conducted based on two algorithms to verify the framework's applicability and feasibility. 相似文献
7.
传统大型升降装置体积大,升降速度低,同步性差、启停冲击大,可靠性低,不满足大型贵重负载的升降需求。通过机械、电子、液压一体化设计,对大型贵重负载重载升降装置的设计方案进行了对比论证,并给出了综合最优解,为某重要产品的设计提供了技术支撑。 相似文献
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Referring to the total surface existing in wheat dough, gluten–starch interfaces are a major component. However, their impact on dough rheology is largely unclear. Common viewpoints, based on starch surface modifications or reconstitution experiments, failed to show unambiguous relations of interface characteristics and dough rheology. Observing hybrid artificial dough systems with defined particle surface functionalization gives a new perspective. Since surface functionalization standardizes particle–polymer interfaces, the impact on rheology becomes clearly transferable and thus, contributes to a better understanding of gluten–starch interfaces. Based on this perspective, the effect of particle/starch surface functionality is discussed in relation to the rheological properties of natural wheat dough and modified gluten–starch systems. A competitive relation of starch and gluten for intermolecular interactions with the network-forming polymer becomes apparent during network development by adsorption phenomena. This gluten–starch adhesiveness delays the beginning of non-linearity under large deformations, thus contributing to a high deformability of dough. Consequently, starch surface functionality affects the mechanical properties, starting from network formation and ending with the thermal fixation of structure. 相似文献
9.
大型铜矿山发展趋势 总被引:1,自引:0,他引:1
尹启华 《有色金属(选矿部分)》2007,(6):46-49
采选装备大型化是普遍趋势,半自磨工艺得到广泛应用且有新的变化,立式磨机I、SA磨等选择性磨矿设备正逐步普及,浮选机单槽容积不断变大,大型浮选机数量快速增长,浮选柱再次被广泛应用并成为最佳最终精选设备,伴生元素回收得到重视并为矿山创造了巨大效益。 相似文献
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