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101.
The TGarden is a genre of responsive environment in which actor–spectators shape dense media sensitive to their movements. These dense fields of light, sound, and material also evolve according to their own composed dynamics, so the agency is distributed throughout the multiple media. These TGardens explore open-ended questions like the following: what makes some time-based, responsive environments compelling, and others flat? How can people improvise gestures without words, that are individually or collectively meaningful? When and how is a movement intentional, or collectively intentional? This paper introduces what has been at stake behind the experimental work: subjectivation, moving from technologies of representation to technologies of performance, and the potential for ethico-aesthetic novelty.  相似文献   
102.
一种安全电子招标系统中专家抽取的方法*   总被引:1,自引:0,他引:1  
介绍了基于PKI架构的公开电子招标系统中专家管理信息系统的专家抽取方法。该方法通过使用加密技术解决专家抽取过程中的安全问题。采用盲签名协议保证抽取信息的机密性、真实性和不可否认性;通过随机算法保证抽取结果的随机化。在基于Web的客户端,监督方在监控抽取过程中对抽取信息未知的情况下签名,确认抽取结果,抽取结果在公布时,获得带有监督方签名的抽取结果。  相似文献   
103.
近年来,人们提出了很多频繁图模式挖掘的算法。首先分析了贪婪搜索策略,然后对各种不同的图数据挖掘的方法进行比较。受购物篮分析的影响,基于ILP方法引起了人们的重视。如何修改各种不同的图数据挖掘方法以适用化学分子数据的挖掘是人们研究的热点问题。因为化学分子不仅是标准的图结构,而且它有典型的频繁环和链结构,还有一些频繁出现的代表原子类型的结点,所以在这个领域有一些特殊问题需要考虑。  相似文献   
104.
单莹  段沙 《计算机与网络》2000,(19):28-28,33
本文阐述了电信管理网(TMN)和公共对象请求代理体系结构的特点,并以实例探讨了CORBA在TMN中的应用。  相似文献   
105.
Summary Via new perspectives, for the time dimension, the present exposition overviews new and recent advances describing a standardized formal theory towards the evolution, classification, characterization and generic design of time discretized operators for transient/dynamic applications. Of fundamental importance in the present exposition are the developments encompassing the evolution of time discretized operators leading to the theoretical design of computational algorithms and their subsequent classification and characterization. And, the overall developments are new and significantly different from the way traditional modal type and a wide variety of step-by-step time marching approaches which we are mostly familiar with have been developed and described in the research literature and in standard text books over the years. The theoretical ideas and basis towards the evolution of a generalized methodology and formulations emanate under the umbrella and framework and are explained via a generalized time weighted philosophy encompassing the semi-discretized equations pertinent to transient/dynamic systems. It is herein hypothesized that integral operators and the associated representations and a wide variety of the so-called integration operators pertain to and emanate from the same family, with the burden which is being carried by a virtual field or weighted time field specifically introduced for the time discretization is strictly enacted in a mathematically consistent manner so as to first permit obtaining the adjoint operator of the original semi-discretized equation system. Subsequently, the selection or burden carried by the virtual or weighted time fields originally introduced to facilitate the time discretization process determines the formal development and outcome of “exact integral operators”, “approximate integral operators”, including providing avenues leading to the design of new computational algorithms which have not been exploited and/or explored to-date and the recovery of most of the existing algorithms, and also bridging the relationships systematically leading to the evolution of a wide variety of “integration operators”. Thus, the overall developments not only serve as a prelude towards the formal developments for “exact integral operators”, but also demonstrate that the resulting “approximate integral operators” and a wide variety of “new and existing integration operators and known methods” are simply subsets of the generalizations of a standardizedW p -Family, and emanate from the principles presented herein. The developments first leading to integral operators in time, and the resulting consequences then systematically leading to not only providing new avenues but additionally also explaining a wide variety of generalized integration operators in time of which single-step time integration operators and various widely recognized algorithms which we are familiar are simply subsets, the associated multi-step time integration operators, and a class of finite element in time integration operators, and their relationships are particularly addressed. The theoretical design developments encompass and explain a variety of time discretized operators, the recovery of various original methods of algorithmic development, and the development of new computational algorithms which have not been exploited and/or explored to-date, and furthermore, permit time discretized operators to be uniquely classified and characterized by algorithmic markers. The resulting and so-called discrete numerically assigned [DNA] algorithmic markers not only serve as a prelude towards providing a standardized formal theory of development of time discretized operators and forum for selecting and identifying time discretized operators, but also permit lucid communication when referring to various time discretized operators. That which constitutes characterization of time discretized operators are the so-called DNA algorithmic markers which essentially comprise of both: (i) the weighted time fields introduced for enacting the time discretization process, and (ii) the corresponding conditions (if any) these weighted time fields impose (dictate) upon the approximations for the dependent field variables and updates in the theoretical development of time discretized operators. As such, recent advances encompassing the theoretical design and development of computational algorithms for transient/dynamic analysis of time dependent phenomenon encountered in engineering, mathematical and physical sciences are overviewed.  相似文献   
106.
The nanopore size effect on translocation of poly(dT)30through Si3N4 membrane is investigated.In this paper,we report that the speed of the poly(dT)30 transport through Si3N4 nanopores can be slowed down by half through increasing the nanopore diameter from 4.8 nm to 10.8 nm.The results are consistent with our simulation results.Besides,the current blockage induced by DNA passing through the nanopore is less obvious as pore diameter is larger,which is in good agreement with the theoretical prediction.The conclusion about DNA transport through nanopores is beneficial for the design of DNA sequencing devices.  相似文献   
107.
智能变电站是统一坚强智能电网的重要组成部分,2010年12月26日,中国国家电网公司第1批智能变电站试点工程——110kV曾家冲变电站的顺利投运,实现了智能变电站从理论到实践的重大突破.智能变电站与传统变电站在设计、建设、控制和管理等方面有质的差别,以湖南省第1个智能变电站(110kV曾家冲智能变电站)建设过程为实例,探讨智能化变电站与常规变电站的区别,具体分析智能变电站智能一次设备、自动化系统及智能化状态监测功能的设计与实现方式,提出该站投运后出现的问题并介绍其解决办法,为后续智能变电站建设提供成功范例.  相似文献   
108.
靠近Sink的传感器节点因为需要转发来自其它节点的数据而承担了更多的通信负载,这些节点往往更早地耗尽自身能量而有更短的生命周期,这种现象被称为“能量空洞”问题.文中基于小世界思想,通过向Sink节点添加一些长链,减少Sink周围节点转发数据的数量来缓解能量空洞的出现,从而延长网络的生命周期.首先对等距传输的网络进行了能耗分析,然后提出采用小世界的策略缓解能量洞的出现,从理论上分析了长链的位置和数量对能量消耗和网络生命周期的影响,提出了一种实用的小世界网络实现方法.仿真实验验证了理论分析结果.  相似文献   
109.
With the realization that more research is needed to explore external factors (e.g., pedagogy, parental involvement in the context of K-12 learning) and internal factors (e.g., prior knowledge, motivation) underlying student-centered mobile learning, the present study conceptually and empirically explores how the theories and methodologies of self-regulated learning (SRL) can help us analyze and understand the processes of mobile learning. The empirical data collected from two elementary science classes in Singapore indicates that the analytical SRL model of mobile learning proposed in this study can illuminate the relationships between three aspects of mobile learning: students’ self-reports of psychological processes, patterns of online learning behavior in the mobile learning environment (MLE), and learning achievement. Statistical analyses produce three main findings. First, student motivation in this case can account for whether and to what degree the students can actively engage in mobile learning activities metacognitively, motivationally, and behaviorally. Second, the effect of students’ self-reported motivation on their learning achievement is mediated by their behavioral engagement in a pre-designed activity in the MLE. Third, students’ perception of parental autonomy support is not only associated with their motivation in school learning, but also associated with their actual behaviors in self-regulating their learning.  相似文献   
110.
Due to the nature of distribution and self-organization, mobile ad hoc networks rely on cooperation between nodes to transfer information. One of the key factors to ensure high communication quality is an efficient assessment scheme for risks and trust of choosing next potential cooperative nodes. Trust model, an abstract psychological cognitive process, is one of the most complex concepts in social relationships, involving factors such as assumptions, expectations and behaviors. All of the above make it difficult to quantify and forecast trust accurately. In this paper, based on the theories of fuzzy recognition with feedback, SCGM(1, 1) model and Markov chain, we present a pattern of prediction making. The analysis and experimental computation show that this scheme is efficient in trust prediction for ad hoc networks.  相似文献   
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