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991.
This paper enlarges the scope of fuzzy-payoff game to n-person form from the previous two-person form. Based on credibility theory, three credibilistic approaches are introduced to model the behaviors of players in different decision situations. Accordingly, three new definitions of Nash equilibrium are proposed for n-person credibilistic strategic game. Moreover, existence theorems are proved for further research into credibilistic equilibrium strategies. Finally, two numerical examples are given to illustrate the significance of credibilistic equilibria in practical strategic games. 相似文献
992.
Hachem Moussa Tong Gao I-Ling Yen Farokh Bastani Jun-Jang Jeng 《Service Oriented Computing and Applications》2010,4(1):17-31
Many application domains are increasingly leveraging service-oriented architecture (SOA) techniques to facilitate rapid system
deployment. Many of these applications are time-critical and, hence, real-time assurance is an essential step in the service
composition process. However, there are gaps in existing service composition techniques for real-time systems. First, admission
control is an essential technique to assure the time bound for service execution, but most of the service composition techniques
for real-time systems do not take admission control into account. A service may be selected for a workflow during the composition
phase, but then during the grounding phase, the concrete service may not be able to admit the workload. Thus, the entire composition
process may have to be repeated. Second, communication time is an important factor in real-time SOA, but most of the existing
works do not consider how to obtain the communication latencies between services during the composition phase. It is clear
that maintaining a full table of communication latencies for all pairs of services is infeasible. Obtaining communication
latencies between candidate services during the composition phase can also be costly, since many candidate services may not
be used for grounding. Thus, some mechanism is needed for estimating the communication latency for composite services. In
this paper, we propose a three-phase composition approach to address the above issues. In this approach, we first use a highly
efficient but moderately accurate algorithm to eliminate most of the candidate compositions based on estimated communication
latencies and assured service response latency. Then, a more accurate timing prediction is performed on a small number of
selected compositions in the second phase based on confirmed admission and actual communication latency. In the third phase,
specific concrete services are selected for grounding, and admissions are actually performed. The approach is scalable and
can effectively achieve service composition for satisfying real-time requirements. Experimental studies show that the three-phase
approach does improve the effectiveness and time for service composition in SOA real-time systems. In order to support the
new composition approach, it is necessary to effectively specify the needed information. In this paper, we also present the
specification model for timing-related information and the extension of OWL-S to support this specification model. 相似文献
993.
Yong Gao 《Artificial Intelligence》2009,173(14):1343-1366
Data reduction is a key technique in the study of fixed parameter algorithms. In the AI literature, pruning techniques based on simple and efficient-to-implement reduction rules also play a crucial role in the success of many industrial-strength solvers. Understanding the effectiveness and the applicability of data reduction as a technique for designing heuristics for intractable problems has been one of the main motivations in studying the phase transition of randomly-generated instances of NP-complete problems.In this paper, we take the initiative to study the power of data reductions in the context of random instances of a generic intractable parameterized problem, the weighted d-CNF satisfiability problem. We propose a non-trivial random model for the problem and study the probabilistic behavior of the random instances from the model. We design an algorithm based on data reduction and other algorithmic techniques and prove that the algorithm solves the random instances with high probability and in fixed-parameter polynomial time O(dknm) where n is the number of variables, m is the number of clauses, and k is the fixed parameter. We establish the exact threshold of the phase transition of the solution probability and show that in some region of the problem space, unsatisfiable random instances of the problem have parametric resolution proof of fixed-parameter polynomial size. Also discussed is a more general random model and the generalization of the results to the model. 相似文献
994.
Duan Li Fucai Qian Jianjun Gao 《Automatic Control, IEEE Transactions on》2009,54(9):2225-2230
Performance-first control for discrete-time LQG is considered in this paper to minimize the probability that the performance index exceeds a preselected threshold via constructing a closed-loop feedback control law. This problem can be converted into a mean-variance control problem which can be solved by developing a nested form of the variance and using polynomial optimization as a solution scheme. 相似文献
995.
Due to the deficiency of information, the membership function of a fuzzy variable cannot be obtained explicitly. It is a challenging work to find an appropriate membership function when certain partial information about a fuzzy variable is given, such as expected value or moments. This paper solves such problems for discrete fuzzy variables via maximum entropy principle and proves some maximum entropy theorems with certain constraints. A genetic algorithm is designed to solve the general maximum entropy model for discrete fuzzy variables, which is illustrated by some numerical experiments. 相似文献
996.
Backbone-based broadcast schemes are effective in alleviating the broadcast storm problem in mobile ad hoc networks (MANETs). However, periodically hello packets used to maintain a backbone usually lead to extra control overhead. In this paper, passive tree-based backbone construction scheme (PTBCS) is proposed as a backbone construction scheme for MANETs. Different from other schemes, each node in PTBCS determines its role by intercepting packet transmissions in the air during a special waiting period. Hence, its most remarkable advantage is that there are no periodical packet transmissions specially for backbone construction. The property that the nodes selected by PTBCS make up a connected dominating set (CDS) of the network is proven with several ideal assumptions. Simulation results show that PTBCS is effective when compared with some other typical backbone construction schemes. 相似文献
997.
Based on the famous Schnorr signature scheme, we propose a new chameleon hash scheme which enjoys all advantages of the previous schemes: collision-resistant, message-hiding, semantic security, and key-exposure-freeness. 相似文献
998.
In this paper, according to classic -matrix method, integral–differential inequality technique and Ito formula, we study asymptotic behavior in mean square sense of stochastic neural networks with infinitely distributed delays by establishing a generalized Halanay inequality. This is a new means for investigating asymptotic behavior of stochastic differential equation. Some useful results are derived. Especially, our methods can be extended to research p-moment asymptotic behavior easily. At last, example and simulations demonstrate the power of our methods. 相似文献
999.
Clonal optimization-based negative selection algorithm with applications in motor fault detection 总被引:1,自引:1,他引:0
The Negative Selection Algorithm (NSA) and clonal selection method are two typical kinds of artificial immune systems. In
this paper, we first introduce their underlying inspirations and working principles. It is well known that the regular NSA
detectors are not guaranteed to always occupy the maximal coverage of the nonself space. Therefore, we next employ the clonal
optimization method to optimize these detectors so that the best anomaly detection performance can be achieved. A new motor
fault detection scheme using the proposed NSA is also presented and discussed. We demonstrate the efficiency of our approach
with an interesting example of motor bearings fault detection, in which the detection rates of three bearings faults are significantly
improved. 相似文献
1000.
Xin-Yu Shao Xue-Zheng Chu Hao-Bo Qiu Liang Gao Jun Yan 《Expert systems with applications》2009,36(2):3223-3233
More and more complicated conceptual design of ship’s engine room (CDSER) heavily depends on designers’ engineering knowledge and existing ship data. To achieve intelligent design at the initial ship design stage, many researchers have made much significant progress in this field, however, most of them only focused on how to find the similar constructed ships. At present, how to utilize these existing data remains an untouched topic. In order to make good use of the existing data and reduce the dependence on designers’ experience, a novel system named Expert System for Aided Conceptual Design of Ship’s Engine Room Automation (ESACD), is elaborated in this study. With the support of the constructed Ship Data Warehouse System, two core subsystems Configuration Selection Assistant (CSA) and Design Scheme Decision Assistant (DSDA) are included in ESACD. A promising approach integrating Fuzzy c-means algorithm (FCM) and Rough Sets Theory (RST) to extract configuration rules from the stored data is adopted in CSA. According to engineers’ proposals, RST is utilized to reason knowledge in incomplete scheme information systems for getting design scheme rules in DSDA, which are useful suggestions for engineers to get better schemes at this stage. Finally, the validity and necessity of this interactive expert system are demonstrated through the CDSER of a new 50,000 DWT Handymax bulk carrier. It is proved that ESACD can efficiently facilitate rapid and intelligent design in CDSER, and reduce the cost of a new ship design. 相似文献