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101.
比较了不同活化剂(KI-Vit C,KI,Vit C,KI-Na_2SO_3,Na_2SO_3,H_2C_2O_4)对5-Cl-PADAB光度测定Pt(Ⅳ)的影响。实验表明,KI、KI-Vit C、KI-Na_2SO_3这3种活化体系最好。其优点为:测定酸度较高,重现性和线性关系好,是良好的活化剂。 相似文献
102.
表面活性剂对碳钢的缓蚀作用及与缓蚀剂的协同效应 总被引:3,自引:4,他引:3
采用动电势扫描法测定了碳钢在饱和(NH4)2CO3溶液中的阳极极化曲线,研究了几种表面活性剂与缓蚀剂复配后的协同缓蚀作用。结果表明:几种表面活性剂均具有较好的缓蚀性能,体系中添加0.1%的量,缓蚀效率都接近90%:当0.05%壬基酚聚氧乙烯醚(TX-10)与0.05%四丁基碘化铵复配时,协同缓蚀效率可达93.3%;应用动电势扫描法能够快速、简便地测定腐蚀速率和评选缓蚀剂。 相似文献
103.
本文从语词含义和造词宗旨入手,剖析了中介机构与评估机构、中间机构、缓冲组织的区别,以论证“教育评估中介机构”概念不当而应予废弃。 相似文献
104.
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106.
Semi‐global and global containment control of multi‐agent systems with second‐order dynamics and input saturation 下载免费PDF全文
This paper considers both semi‐global and global containment control for a second‐order multi‐agent system that is composed by a network of identical harmonic oscillators or double integrators with multiple leaders and input saturation. A distributed low gain feedback algorithm is proposed to solve the semi‐global containment control problem for the network whose topology is directed and initial condition is taken from any a priori given bounded set. In particular, by using a parametric Lyapunov equation approach, M‐matrix properties and algebraic graph theory, an upper bound of the low gain parameter is estimated such that the low gain feedback matrix can be analytically determined without involving numerical computation. Furthermore, under the assumption that the induced subgraph formed by the followers is strongly connected and detail balanced, two linear feedback protocols are designed for coupled harmonic oscillators and coupled double integrators, respectively, to asymptotically achieve the global containment control of the network with any initial condition. Finally, numerical examples are given to illustrate the effectiveness of the theoretical results. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
107.
Time Averaging Algorithms with Stopping Rules for Multi‐Agent Consensus with Noisy Measurements 下载免费PDF全文
A time averaging technique is introduced to consensus algorithms in networked multi‐agent systems under a noisy environment. Each agent communicates with its neighboring agents via a constant gain, while the time averaging states of the agents are considered as the values for agreement. The variation of the time averaging states then is evaluated at a specific number of iterations, where the number is given explicitly in terms of parameters related to the consensus accuracy and its probabilistic guarantee. This result establishes a rigorous stopping rule for the multi‐agent consensus with noisy measurements. Several results on this type of stopping rules are provided for undirected, directed, and time‐varying communication graphs. These theoretical results are illustrated through numerical examples. 相似文献
108.
High‐precision formation control of nonlinear multi‐agent systems with switching topologies: A learning approach 下载免费PDF全文
Arbitrary high precision is considered one of the most desirable control objectives in the relative formation for many networked industrial applications, such as flying spacecrafts and mobile robots. The main purpose of this paper is to present design guidelines of applying the iterative schemes to develop distributed formation algorithms in order to achieve this control objective. If certain conditions are met, then the control input signals can be learned by the developed algorithms to accomplish the desired formations with arbitrary high precision. The systems under consideration are a class of multi‐agent systems under directed networks with switching topologies. The agents have discrete‐time affine nonlinear dynamics, but their state functions do not need to be identical. It is shown that the learning processes resulting from the relative output formation of multi‐agent systems can converge exponentially fast with the increase of the iteration number. In particular, this work induces a distributed algorithm that can simultaneously achieve the desired relative output formation between agents and regulate the movement of multi‐agent formations as desired along the time axis. The illustrative numerical simulations are finally performed to demonstrate the effectiveness and performance of the proposed distributed formation algorithms. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
109.
In this paper, a novel framework for networked estimation of multi‐agent systems subject to presence of actuator faults is proposed. This framework is developed based on the notion of sub‐observers where within a group of sub‐observers each sub‐observer estimates certain states that are conditioned on a given input, output, and other state information. We model the overall estimation process by a weighted estimation (WE) digraph. By selecting an appropriate path in the WE digraph, an assigned supervisor can select and configure a set of sub‐observers to successfully estimate all the system states. In the presence of large intermittent disturbances, noise, and faults certain sub‐observers may become invalid, and consequently the supervisor reconfigures the set of sub‐observers by selecting a new path in the estimation digraph such that the impacts of these uncertainties are confined to only the local estimators. This will prevent the propagation of uncertainties on the estimation performance of the entire multi‐agent system. Simulation results provided for a five satellite formation flight system in deep space confirm the validity and applicability of our proposed analytical work. 相似文献
110.
Simon Penny 《Digital Creativity》2013,24(3):197-204
This essay begins with discussion of four relatively recent works which are representative of major themes and preoccupations in Artificial Life Art: ‘Propagaciones’ by Leo Nuñez; ‘Sniff’ by Karolina Sobecka and Jim George; ‘Universal Whistling Machine’ by Marc Boehlen; and ‘Performative Ecologies’ by Ruari Glynn. This essay is an attempt to contextualise these works by providing an overview of the history and forms of Artificial Life Art as it has developed over two decades, along with some background in the ideas of the Artificial Life movement of the late 1980s and 1990s.1 相似文献