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991.
Computer music composition is the dream of computer music researchers. In this paper, a top-down approach is investigated to discover the rules of musical composition from given music objects and to create a new music object of which style is similar to the given music objects based on the discovered composition rules. The proposed approach utilizes the data mining techniques in order to discover the styled rules of music composition characterized by music structures, melody styles and motifs. A new music object is generated based on the discovered rules. To measure the effectiveness of the proposed approach in computer music composition, a method similar to the Turing test was adopted to test the differences between the machine-generated and human-composed music. Experimental results show that it is hard to distinguish between them. The other experiment showed that the style of generated music is similar to that of the given music objects.  相似文献   
992.
In the adaptive neural control design, since the number of hidden neurons is finite for real‐time applications, the approximation errors introduced by the neural network cannot be inevitable. To ensure the stability of the adaptive neural control system, a switching compensator is designed to dispel the approximation error. However, it will lead to substantial chattering in the control effort. In this paper, an adaptive dynamic sliding‐mode neural control (ADSNC) system composed of a neural controller and a fuzzy compensator is proposed to tackle this problem. The neural controller, using a radial basis function neural network, is the main controller and the fuzzy compensator is designed to eliminate the approximation error introduced by the neural controller. Moreover, a proportional‐integral‐type adaptation learning algorithm is developed based on the Lyapunov function; thus not only the system stability can be guaranteed but also the convergence of the tracking error and controller parameters can speed up. Finally, the proposed ADSNC system is implemented based on a field programmable gate array chip for low‐cost and high‐performance industrial applications and is applied to control a brushless DC (BLDC) motor to show its effectiveness. The experimental results demonstrate the proposed ADSNC scheme can achieve favorable control performance without encountering chattering phenomena. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society  相似文献   
993.
The adaptive output recurrent cerebellar model articulation control (AORCMAC) is an adaptive system with simple computation, good generalization capability and fast learning property. The proposed AORCMAC has superior capability to the conventional cerebellar model articulation controller (CMAC) in efficient learning mechanism and dynamic response. In this study, an intelligent backstepping tracking control system is proposed for wheeled inverted pendulums (WIPs) with unknown system dynamics and external disturbance. In this control system, an ABORCMAC is used to copy an ideal backstepping control (IBC), and a compensated controller is designed to compensate for difference between the IBC law and AORCMAC. Moreover, all adaptation laws of the proposed system are derived based on the Lyapunov stability analysis, the Taylor linearization technique, so that the stability of the closed-loop system can be guaranteed.  相似文献   
994.
In an e-service environment, workflow involves not only a single organization but also a number of business partners. Therefore, workflow inter-operability in such an environment is an important issue for enacting workflows. In this article, we introduce our approach of using workflow views as a fundamental support for E-service workflow inter-operability and for controlled visibility of (sub-)workflows by external parties. We discuss various aspects of a workflow view, and their semantics with example usage. Furthermore, we develop a contract model based on workflow views and demonstrate how management of e-contracts can be facilitated, with an Internet start-up E-service inter-organization workflow example.  相似文献   
995.
利用X射线双能量进行物质属性的判别,是机场、车站行李安全检查的一项基本技术.未经滤波的单个140KV的X射线源,发射的是连续能谱的X射线,采用两种不同能谱响应的探测器分别得到高低能量的透射信号.综合考虑连续能谱效应和探测器效率的影响,推导出高低能量的线性衰减系数比值的逼近多项式,对于固定的射线源和探测器这个多项式的各个系数是不变的.利用这种方法对物质属性进行判别,并给出了实验结果.  相似文献   
996.
Loops are critical elements in boundary representation (B-rep) models because they link all edges corresponding to a face. Loops can be used in feature recognition for identifying depressions or protrusions. In real 3D CAD models, however, features typically lie across multiple faces, which is beyond the data structure of current B-rep models. This study presents a virtual loop concept to account for all loop types used in CAD models, and develops algorithms for recognizing them. In accordance with the complexity of the recognition algorithm, this study defines three types of loop: single, virtual, and multivirtual. A single loop is the current loop recorded in the B-rep model. A virtual loop lies across faces that are at least G1 continuous. Finally, a multivirtual loop lies across faces that are either G0 or G1 continuous. The proposed loop structure provides a more complete data structure for recognizing various types of features in feature-recognition modules. Several realistic CAD models are presented to confirm the feasibility of the proposed loop-recognition and feature-recognition methods.  相似文献   
997.
In a recent paper, Chiu et al. [Intra-supply chain system with multiple sales locations and quality assurance, Expert Systems with Applications, http://dx.doi.org/10.1016/j.eswa.2012.11.008] used the mathematical modeling and differential calculus to derive the optimal replenishment lot-size and shipment policy that minimizes overall costs for a specific intra-supply chain system. This paper proposes a two-phase straightforward algebraic approach to replace the use of calculus on the cost function for determining the optimal production-shipment policy for such a specific system. This alternative approach enables practitioners who may not have sufficient knowledge of calculus to manage the real-world intra-supply chain systems more effectively.  相似文献   
998.
Workflow technology has recently been employed not only within businesses but also as a framework for implementing e-services over the Internet. Such e-services typically require collaborative enactment of workflows across multiple organizations. In this paper, we propose the use of workflow views as a fundamental support mechanism for the interoperability of multiple workflows across business organizations. We present a meta-model of workflow views and their semantics using a cross-organization workflow example based on a supply-chain e-service. We also formulate an interoperation model of workflow views and its consistency criteria. Finally, this paper presents an implementation of the model based on XML and contemporary Web services technologies, with adaptation to our E-ADOME workflow engine.  相似文献   
999.
This paper employs mathematical modeling for solving manufacturing run time problem with random defective rate and stochastic machine breakdown. In real life manufacturing systems, generation of nonconforming items and unexpected breakdown of production equipment are inevitable. For the purpose of addressing these practical issues, this paper studies a system that may produce defective items randomly and it is also subject to a random equipment failure. A no resumption inventory control policy is adopted when breakdown occurs. Under such a policy, the interrupted lot is aborted and malfunction machine is immediately under repair. A new lot will be started only when all on-hand inventory are depleted. Modeling and numerical analyses are used to establish the solution procedure for such a problem. As a result, the optimal manufacturing run time that minimizes the long-run average production–inventory cost is derived. A numerical example is provided to show how the solution procedure works as well as the usages of research results.  相似文献   
1000.
With rapidly growing and increasingly competitive marketplace, companies are constantly performing strategic planning for growth strategy and repositioning itself for even more disruptive changes to achieve or regain market leadership, which makes selection of strategic partners play a very critical role in the corporate growth strategy. How to reallocate limited resources to maximize return on investment (ROI), significantly reduce budget overruns and effectively leverage customer value analysis has become a key research topic for both pragmatic and academic research groups. Previous strategy research findings are mostly focused on resource based view (RBV) and transaction cost to explore the selection strategy on strategic partners, while shed very little light on the value of strategic partners as this becomes an inevitable component in strategy management. In order to bridge such a gap, this research is in an attempt to perform a thorough value analysis of strategic partners using both Markov chain and Hierarchical Bayesian. With Markov chain as a base, this research performs data collection and analysis using previous value status of strategic partners, and their migration pathways, along with Hierarchical Bayesian, to establish individualized transition probability matrix and further predict the future migration pathways of strategic partners, eventually providing key insights for companies to develop strategies on how to manage and strengthen key partnerships.  相似文献   
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