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81.
This paper presents a fuzzy system for controlling the fire command in a surface-to-surface engagement by assuming siege of friendly side by enemy forces. The system must be capable of interacting with a dynamic and uncertain battle world in a real-time manner. In siege situation, it is assumed that the enemy troops are advancing toward friendly side in different directions and the defence resources are limited and nonrenewable at a single platform. Thus, resource allocation problem in a real-time manner is an important and vital component of battle management until coming of auxiliary forces. This paper addresses the design of a fuzzy system as an efficient tool for real-time decision-making in order to optimize the defense resource allocation in engagement. 相似文献
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针对制造商负责回收的闭环供应链决策问题,构建了集中决策供应链和三种渠道权力结构的分散决策供应链优化模型,探讨渠道权力结构对闭环供应链决策及绩效的影响作用。研究发现,三种渠道权力结构下的分散决策供应链都处于不协调状态,且不协调程度与渠道权力结构相关;存在领导权的Stackelberg供应链零售定价高于无领导权的Bertrand供应链,制造商领导零售定价高于零售商领导供应链;存在领导权供应链的回收比例低于无领导权供应链,制造商领导的回收比例低于零售商领导供应链;存在领导权供应链的系统利润低于无领导权供应链,制造商领导的系统利润低于零售商领导供应链;供应链企业利润在其自身领导系统中最高,势均力敌系统中次之,对方领导系统中最低。 相似文献
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The alarming growth rate in the online game industry calls for a need of understanding the determinants of online gamers’ behaviour. Investigating how online gamers choose different online characters assists online game vendors to design characters that match the needs of different online gamers. Recently, numerous online game designers have introduced celebrity figures as characters for certain online games. The popularity of those celebrities has resulted in greater awareness of these games, and hopefully further increases the playability of online games. While different online gamers are motivated by different desires for playing, it is insufficiently researched whether these online celebrity characters have actually altered players’ choice in giving preference to these games. Thus, this study conducts an experimental design to study the reasons behind players’ choice of characters by studying how online games perceive the interpersonal attractiveness of celebrity online characters, and how online gamers with different playing motivations display different behaviours in their choice of online game characters. Results from the survey filled out by participants after the experiments show that the attractiveness of celebrity online characters is significantly higher than that of non-celebrity characters. Further, online game players with a social playing motivation tend to choose celebrities as their online game characters. 相似文献
87.
Detecting communities is of great importance in social network analysis. However it is an issue that has not yet been satisfactorily solved, despite the efforts made by interdisciplinary research communities over the past few years, because of the nature of complexity in deciding how community structures should be recognized. In this paper we propose an approach based on cooperative game theory for community detection in social networks. We regard individuals as players, and regard communities as coalitions formed by players, and model community detection problem as the formation and optimization of coalitions. Furthermore, we define coalition profile for players to indicate coalitions that players joined, the order of a coalition profile is defined as the number of coalitions in a coalition profile, and we introduce a utility function to measure preference of coalition profiles. Accordingly, we propose an algorithm to detect a coalition profile with maximal utility function values. We have implemented the algorithms developed in this study and experimental results demonstrate the effectiveness of our approaches. 相似文献
88.
We consider the problem of revenue maximization on multi‐unit auctions where items are distinguished by their relative values; any pair of items has the same ratio of values to all buyers. As is common in the study of revenue maximizing problems, we assume that buyers' valuations are drawn from public known distributions and they have additive valuations for multiple items. Our problem is well motivated by sponsored search auctions, which made money for Google and Yahoo! in practice. In this auction, each advertiser bids an amount bi to compete for ad slots on a web page. The value of each ad slot corresponds to its click‐through‐rate, and each buyer has her own per‐click valuations, which is her private information. Obviously, a strategic bidder may bid an amount that is different with her true valuation to improve her utility. Our goal is to design truthful mechanisms avoiding this misreporting. We develop the optimal (with maximum revenue) truthful auction for a relaxed demand model (where each buyer i wants at most di items) and a sharp demand model (where buyer i wants exactly di items). We also find an auction that always guarantees at least half of the revenue of the optimal auction when the buyers are budget constrained. Moreover, all of the auctions we design can be computed efficiently, that is, in polynomial time. 相似文献
89.
BackgroundPrior studies observed involvement with video games to vary between different sociodemographic strata with considerable higher gaming time in males compared to females. However, empirical evidence explaining the gender gap in gaming time is still scarce. The present study aims to evaluate if the higher gaming time can be attributed to gender specific game genre preferences.MethodsA nationwide representative survey comprising 3073 participants aged 16–93 years (M = 49.1; SD = 18.2) was conducted. Video game use and genre preferences were assessed via a written questionnaire. OLS regression and subsequent mediation analyses were used to determine significant predictors of gaming time and to evaluate the contribution of genre preferences.ResultsHigher age, high education and employment predicted lower gaming time whereas male gender and the preference of certain game genres predicted higher gaming time. Mediation analyses revealed that the higher gaming time of males is fully mediated by the higher preference of role-playing and shooter games among this gender group.ConclusionThe higher gaming time of men is fully accounted for by the male specific preference for certain game genres. Future research should address the functional connection between genre preferences and gaming behavior in further detail. 相似文献
90.
Mario Guajardo Mikael Rönnqvist 《International Transactions in Operational Research》2016,23(3):371-392
Collaboration in transportation between two or more agents is becoming an important approach to find efficient solutions or plans. Efficiency can be measured in, for example, lower cost or more flexibility. An important aspect of the collaboration is to decide on how to share the benefits—for example, cost, profit, or resources. There are many sharing mechanisms or cost allocations proposed in the literature. Some are based on simple proportional rules and others are based on theoretical concepts found in game theory. We provide a survey on cost allocation methods found in the literature on collaborative transportation, including problems on planning, vehicle routing, traveling salesman, distribution, and inventory. A total of 55 scientific articles compose the main part of the survey, most of them published between 2010 and 2015. We identify more than 40 cost allocation methods used in this stream of literature. We describe the theoretical basis for the main methods as well as the cases where they are used. We also report savings from the collaborations when they are based on industrial data. Some directions for future research are discussed. 相似文献