全文获取类型
收费全文 | 34239篇 |
免费 | 4327篇 |
国内免费 | 3531篇 |
专业分类
电工技术 | 4531篇 |
技术理论 | 4篇 |
综合类 | 5705篇 |
化学工业 | 734篇 |
金属工艺 | 620篇 |
机械仪表 | 2984篇 |
建筑科学 | 1417篇 |
矿业工程 | 1121篇 |
能源动力 | 823篇 |
轻工业 | 790篇 |
水利工程 | 990篇 |
石油天然气 | 633篇 |
武器工业 | 599篇 |
无线电 | 3262篇 |
一般工业技术 | 1780篇 |
冶金工业 | 581篇 |
原子能技术 | 118篇 |
自动化技术 | 15405篇 |
出版年
2024年 | 138篇 |
2023年 | 342篇 |
2022年 | 578篇 |
2021年 | 665篇 |
2020年 | 876篇 |
2019年 | 850篇 |
2018年 | 801篇 |
2017年 | 948篇 |
2016年 | 1150篇 |
2015年 | 1311篇 |
2014年 | 1977篇 |
2013年 | 2124篇 |
2012年 | 2448篇 |
2011年 | 2816篇 |
2010年 | 2086篇 |
2009年 | 2305篇 |
2008年 | 2446篇 |
2007年 | 2920篇 |
2006年 | 2628篇 |
2005年 | 2229篇 |
2004年 | 1760篇 |
2003年 | 1542篇 |
2002年 | 1252篇 |
2001年 | 1095篇 |
2000年 | 963篇 |
1999年 | 770篇 |
1998年 | 641篇 |
1997年 | 495篇 |
1996年 | 404篇 |
1995年 | 346篇 |
1994年 | 300篇 |
1993年 | 201篇 |
1992年 | 165篇 |
1991年 | 127篇 |
1990年 | 80篇 |
1989年 | 96篇 |
1988年 | 55篇 |
1987年 | 35篇 |
1986年 | 25篇 |
1985年 | 22篇 |
1984年 | 14篇 |
1983年 | 24篇 |
1982年 | 12篇 |
1981年 | 5篇 |
1980年 | 6篇 |
1979年 | 5篇 |
1978年 | 3篇 |
1977年 | 6篇 |
1973年 | 3篇 |
1957年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
101.
Source number estimation and separation algorithms of underdetermined blind separation 总被引:2,自引:0,他引:2
YANG ZuYuan TAN BeiHai ZHOU GuoXu ZHANG JinLong 《中国科学F辑(英文版)》2008,(10):1623-1632
Recently, sparse component analysis (SCA) has become a hot spot in BSS research. Instead of independent component analysis (ICA), SCA can be used to solve underdetermined mixture efficiently. Two-step approach (TSA) is one of the typical methods to solve SCA based BSS problems. It estimates the mixing matrix before the separation of the sources. K-means clustering is often used to estimate the mixing matrix. It relies on the prior knowledge of the source number strongly. However, the estimation of the source number is an obstacle. In this paper, a fuzzy clustering method is proposed to estimate the source number and mixing matrix simultaneously. After that, the sources are recovered by the shortest path method (SPM). Simulations show the availability and robustness of the proposed method. 相似文献
102.
SUN Feng 《数字社区&智能家居》2008,(30)
系统采用Oracle数据库作为开发平台,VB.net为开发工具研制而成。系统借鉴银行和电力企业信用等级评价的规则,结合水司水费收缴的历史纪录及各客户的实际情况,运用自动采集程序,从原有的营销系统和财务系统自动录入数据,再通过优化的模糊概率、神经网络程序,对用户进行交纳水费信用等级评定,建立客户交纳水费风险预警机制。 相似文献
103.
ZHAO Wei-zhou 《数字社区&智能家居》2008,(22)
SAR图像存在强烈的相干斑噪声,传统方法不能很好对其分割。文章基于模糊理论,通过选择图像特征,构造模糊集,借助最大隶属度原则进行了SAR图像分割算法的设计,并借助SAR图像分别进行了参数调节和窗口选择的实验,获得了满意的分割结果。实验结果表明,该算法对于SAR图像分割可行有效。 相似文献
104.
Mathematical methods of geoinformatics. III. Fuzzy comparisons and recognition of anomalies in time series 总被引:1,自引:0,他引:1
A. D. Gvishiani S. M. Agayan Sh. R. Bogoutdinov J. Zlotnicki J. Bonnin 《Cybernetics and Systems Analysis》2008,44(3):309-323
The search for anomalies in time series by methods of fuzzy logic is further explored. The algorithms DRAS and FLARS underlying
these methods are further developed in the form of the algorithm FCARS that is completely based on fuzzy comparisons.
Parts 1 and 2 were published in Cybernetics and Systems Analysis, No. 2, 2002 and No. 4, 2003.
__________
Translated from Kibernetika i Sistemnyi Analiz, No. 3, pp. 3–18, May–June 2008. 相似文献
105.
Intelligence has been an object of study for a long time. Different architectures try to capture and reproduce these aspects into artificial systems (or agents), but there is still no agreement on how to integrate them into a general framework. With this objective in mind, we propose an architectural methodology based on the idea of intentional configuration of behaviors. Behavior‐producing modules are used as basic control components that are selected and modified dynamically according to the intentions of the agent. These intentions are influenced by the situation perceived, knowledge about the world, and internal variables that monitor the state of the agent. The architectural methodology preserves the emergence of functionality associated with the behavior‐based paradigm in the more abstract levels involved in configuring the behaviors. Validation of this architecture is done using a simulated world for mobile robots, in which the agent must deal with various goals such as managing its energy and its well‐being, finding targets, and acquiring knowledge about its environment. Fuzzy logic, a topologic map learning algorithm, and activation variables with a propagation mechanism are used to implement the architecture for this agent. 相似文献
106.
The Dynamics of Syntactic Knowledge 总被引:1,自引:0,他引:1
The syntactic approach to epistemic logic avoids the logicalomniscience problem by taking knowledge as primary rather thanas defined in terms of possible worlds. In this study, we combinethe syntactic approach with modal logic, using transition systemsto model reasoning. We use two syntactic epistemic modalities:knowing at least a set of formulae and knowingat most a set of formulae. We are particularly interestedin models restricting the set of formulae known by an agentat a point in time to be finite. The resulting systems are investigatedfrom the point of view of axiomatization and complexity. Weshow how these logics can be used to formalise non-omniscientagents who know some inference rules, and study their relationshipto other systems of syntactic epistemic logics, such as Ågotnesand Walicki (2004, Proc. 2nd EUMAS, pp. 110), Alechinaet al. (2004, Proc. 3rd AAMAS, pp. 601613), Duc (1997,J. Logic Comput., 7, 633648). 相似文献
107.
We begin by showing how to faithfully encode the Classical ModalDisplay Logic (CMDL) of Wansing into the Calculus of Structures(CoS) of Guglielmi. Since every CMDL calculus enjoys cut-elimination,we obtain a cut-elimination theorem for all corresponding CoScalculi. We then show how our result leads to a minimal cut-freeCoS calculus for modal logic S5. No other existing CoS calculifor S5 enjoy both these properties simultaneously. 相似文献
108.
The paper contains a review of some results concerning probability theory on MV algebras (laws of large numbers, central
limit theorem, martingale convergence theorem). Also some algebraic and methodical aspects are discussed. 相似文献
109.
110.
感官评定是控制烹饪菜品质量的重要途径之一,文章以川菜代表性菜品——鱼香肉丝为评定对象,选取色、香、味、形、质等因素并设置合理的权重,对同一试验小组A、B、C、D、E等5道鱼香肉丝菜肴进行模糊数学综合评定。试验结果表明,用模糊数学综合评判法,能客观而准确地区分出不同烹饪菜肴的差异程度和等级,即5道鱼香肉丝感官评定等级从高到低为:C〉D〉E〉A〉B。 相似文献