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151.
证券投资交易系统技术实现中若干问题的研究 总被引:1,自引:1,他引:0
文章给出了一个证券交易与信托投资系统的网络结构框架和技术实现方法,并针对该类系统技术实现过程中所面临的一些关键性技术问题进行了研究与探讨,给出了相应的解决方案。这些问题与解决方案对于基于Internet的证券交易系统以及信托投资管理系统也具有一定意义。 相似文献
152.
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
153.
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
154.
Taghi M. Khoshgoftaar Xiaojing Yuan Edward B. Allen 《Empirical Software Engineering》2000,5(4):313-330
Software product and process metrics can be useful predictorsof which modules are likely to have faults during operations.Developers and managers can use such predictions by softwarequality models to focus enhancement efforts before release.However, in practice, software quality modeling methods in theliterature may not produce a useful balance between the two kindsof misclassification rates, especially when there are few faultymodules.This paper presents a practical classificationrule in the context of classification tree models that allowsappropriate emphasis on each type of misclassification accordingto the needs of the project. This is especially important whenthe faulty modules are rare.An industrial case study using classification trees, illustrates the tradeoffs.The trees were built using the TREEDISC algorithm whichis a refinement of the CHAID algorithm. We examinedtwo releases of a very large telecommunications system, and builtmodels suited to two points in the development life cycle: theend of coding and the end of beta testing. Both trees had onlyfive significant predictors, out of 28 and 42 candidates, respectively.We interpreted the structure of the classification trees, andwe found the models had useful accuracy. 相似文献
155.
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
156.
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
157.
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
158.
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
159.
塔里木盆地塔中北坡已经发现了致密-低孔低渗岩性油气藏,主要层位为志留系下统柯坪塔格组下砂岩段,本区岩性油气藏具有典型的砂泥岩薄互层特征,而且横向变化大、非均质性极强,含油砂岩的声波阻抗和泥岩的声波阻抗存在较大范围的重叠,难以区分。针对本区岩性圈闭,致密碎屑岩储层的地质、地球物理特点存在的难点,开展地震储层综合预测研究,提出将基于部分叠加数据的叠前同时反演和地质统计学结合起来的致密碎屑岩储层地震反演技术,通过实际应用,验证了该反演技术对储层预测的有效性。 相似文献
160.
以实验室模拟废水为进水,在SBR反应器中利用好氧颗粒污泥进行N、P的去除效率研究.研究表明:在运行周期约为4h,进水COD控制在500~1200 mg/L之间,室温条件下,好氧颗粒污泥对COD、氨氮、硝氮、TP的去除率稳定维持在97%、95%、92%、86%,说明好氧颗粒污泥特有的结构特性和生物特性有利于脱氮除磷. 相似文献