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71.
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
72.
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
73.
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
74.
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
75.
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
76.
黄河滩岸的崩塌失稳将会对滩地和村庄造成严重冲蚀,甚至造成堤防冲决,对黄河滩岸稳定性及其影响因素的敏感性进行分析具有重要的工程实践意义.选择了影响滩岸稳定性较大的主要因素(土体凝聚力c、坡体内水头H和坡角α)进行分析.由c、H及α变化组成不同分析工况,采用边坡稳定性分析方法,分析了滩岸稳定性,并在此基础上研究了滩岸稳定性对c、H及α的敏感性.分析结果表明:在各种计算工况下,黄河滩岸是稳定的;c是影响滩岸坡体稳定性最强的因素,其敏感性随坡角及水头的增大而增强;H对滩岸坡体稳定性影响次之,其敏感性随坡角的增大而增大,随凝聚力的增大而减小;α对坡体稳定的敏感性相对较小,其随凝聚力的增大而减小,随水头的变化不明显. 相似文献
77.
研究了低能电子束辐照对AlGaInP基红光LED性能的影响,利用不同剂量的电子束对AlGaInP基红光LED进行辐照,将辐照后和未辐照的LED的发光强度进行对比.结果表明:辐照后LED的发光强度增加,同一外延片上测试点的发光强度的增加不均匀. 相似文献
78.
以元认知策略为理论依据,研究了"一词多义"词汇掌握量对词汇总量的影响,并针对"一词多义"词汇学习,探讨了哪些元认知策略更有助于英语词汇学习和"一词多义"词汇的学习,从而通过学习方法提高词汇习得的效率。 相似文献
79.
Jingquan Sha Cheng Wang Jun Peng Aixiang Tian Jing Chen Pengpeng Zhang 《Inorganic chemistry communications》2007,10(12):1469-1472
A novel two-dimensional molybdenum oxide polymer, [Mo4O13]n · 2nH3O, has been prepared under specific hydrothermal conditions and characterized by IR spectroscopy and TG analysis. Single-crystal X-ray diffraction analysis reveals that compound 1 exhibits a (3, 4, 5, 6)-connected 2D layer structure with (32·4)(32·53·8)(3·42·54·6·82)(34·43·54·64) topology, which is constructed by two parallel molybdenum oxide dimeric chains (Mo2O10)n bound together by the dimer of Mo2O9 subunits via the sharing of corners. Additionally, the electrochemistry activity of compound 1 is also reported. 相似文献
80.
Design of fair surfaces over irregular domains is a fundamental problem in computer-aided geometric design (CAGD), and has
applications in engineering sciences (in aircraft, automobile, ship science etc.). In the design of fair surfaces over irregular
domains defined over scattered data, it was widely accepted till recently that the classical Delaunay triangulation be used
because of its global optimum property. However, in recent times it has been shown that for continuous piecewise linear surfaces,
improvements in the quality of fit can be achieved if the triangulation pattern is made dependent upon some topological or
geometric property of the data set or is simply data dependent. The fair surface is desired because it ensures smooth and
continuous surface planar cuts, and these in turn ensure smooth and easy production of the surface in CAD/CAM, and favourable
resistance properties. In this paper, we discuss a method for construction of C1 piecewise polynomial parametric fair surfaces which interpolate prescribed ℜ3 scattered data using spaces of parametric splines defined on H3 triangulation. We show that our method is more specific to the cases when the projection on a 2-D plane may consist of triangles of zero area, numerically stable and robust, and computationally inexpensive and fast. Numerical
examples dealing with surfaces approximated on plates, and on ships have been presented. 相似文献