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991.
介绍在Logix5000编程软件中如何添加一台新的PowerFlex70变频器,以及如何通过程序让其实现双向双速功能。 相似文献
992.
WANG HuiMing & XIA XiangGen School of Electronic Information Engineering Xi’an Jiaotong University Xi’an China State Key Laboratory of Integrated Services Networks Xidian University Department of Electrical Computer Engineering University of Delaware Newark DE USA 《中国科学:信息科学(英文版)》2011,(8):1547-1561
Cooperative communications is a promising technique for future high speed wireless communications.These systems may be formulated as virtual multi-input multi-output (MIMO) systems where spatial/cooperetive diversity is a key advantage. However,different from MIMO systems,one of the major chal- lenges for cooperative communications systems is that the cooperative transmissions in cooperative systems may be neither time nor frequency synchronized,since the transmissions are from multiple cooperative nodes at... 相似文献
993.
994.
C. Carasco 《Computer Physics Communications》2010,181(6):1161-629
MCNP Output Data Analysis with ROOT (MODAR) is a tool based on CERN's ROOT software. MODAR has been designed to handle time-energy data issued by MCNP simulations of neutron inspection devices using the associated particle technique. MODAR exploits ROOT's Graphical User Interface and functionalities to visualize and process MCNP simulation results in a fast and user-friendly way. MODAR allows to take into account the detection system time resolution (which is not possible with MCNP) as well as detectors energy response function and counting statistics in a straightforward way.
Program summary
Program title: MODARCatalogue identifier: AEGA_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEGA_v1_0.htmlProgram obtainable from: CPC Program Library, Queen's University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 155 373No. of bytes in distributed program, including test data, etc.: 14 815 461Distribution format: tar.gzProgramming language: C++Computer: Most Unix workstations and PCOperating system: Most Unix systems, Linux and windows, provided the ROOT package has been installed. Examples where tested under Suse Linux and Windows XP.RAM: Depends on the size of the MCNP output file. The example presented in the article, which involves three two-dimensional 139×740 bins histograms, allocates about 60 MB. These data are running under ROOT and include consumption by ROOT itself.Classification: 17.6External routines: ROOT version 5.24.00 (http://root.cern.ch/drupal/)Nature of problem: The output of an MCNP simulation is an ASCII file. The data processing is usually performed by copying and pasting the relevant parts of the ASCII file into Microsoft Excel. Such an approach is satisfactory when the quantity of data is small but is not efficient when the size of the simulated data is large, for example when time-energy correlations are studied in detail such as in problems involving the associated particle technique. In addition, since the finite time resolution of the simulated detector cannot be modeled with MCNP, systems in which time-energy correlation is crucial cannot be described in a satisfactory way. Finally, realistic particle energy deposit in detectors is calculated with MCNP in a two-step process involving type-5 then type-8 tallies. In the first step, the photon flux energy spectrum associated to a time region is selected and serves as a source energy distribution for the second step. Thus, several files must be manipulated before getting the result, which can be time consuming if one needs to study several time regions or different detectors performances. In the same way, modeling counting statistics obtained in a limited acquisition time requires several steps and can also be time consuming.Solution method: In order to overcome the previous limitations, the MODAR C++ code has been written to make use of CERN's ROOT data analysis software. MCNP output data are read from the MCNP output file with dedicated routines. Two-dimensional histograms are filled and can be handled efficiently within the ROOT framework. To keep a user friendly analysis tool, all processing and data display can be done by means of ROOT Graphical User Interface. Specific routines have been written to include detectors finite time resolution and energy response function as well as counting statistics in a straightforward way.Additional comments: The possibility of adding tallies has also been incorporated in MODAR in order to describe systems in which the signal from several detectors can be summed. Moreover, MODAR can be adapted to handle other problems involving two-dimensional data.Running time: The CPU time needed to smear a two-dimensional histogram depends on the size of the histogram. In the presented example, the time-energy smearing of one of the 139×740 two-dimensional histograms takes 3 minutes with a DELL computer equipped with INTEL Core 2. 相似文献995.
The objective of the paper is to describe a novel finite element computational method based on a strain energy density function and to implement it in the object-oriented environment. The original energy-based finite element was put into the known standard framework of classes and handled in a different manner. The nonlinear properties of material are defined with a modified strain energy density function. The local relaxation procedure proposed as a method used to resolve a nonlinear problem is implemented in C++ language. The hexahedral element with eight nodes as well as the adaptation of the nonlinear finite element is introduced. The chosen numerical model is made of nearly incompressible hyperelastic material. The application of the proposed element is shown on the example of a rectangular parallelepiped with a hollow port. 相似文献
996.
K.C. Leung Author Vitae Author Vitae 《Pattern recognition》2010,43(3):949-961
The problem of recognizing offline handwritten Chinese characters has been investigated extensively. One difficulty is due to the existence of characters with very similar shapes. In this paper, we propose a “critical region analysis” technique which highlights the critical regions that distinguish one character from another similar character. The critical regions are identified automatically based on the output of the Fisher's discriminant. Additional features are extracted from these regions and contribute to the recognition process. By incorporating this technique into the character recognition system, a record high recognition rate of 99.53% on the ETL-9B database is obtained. 相似文献
997.
In this paper, we develop mathematical models for simultaneous consideration of suitability and optimality in asset allocation. We use a hybrid approach that combines behavior survey, cluster analysis, analytical hierarchy process and fuzzy mathematical programming. 相似文献
998.
999.
郑紫英 《数字社区&智能家居》2011,(18)
程序设计语言课程在计算机学科中占有重要地位,但对中职生来说,它是一门较难学习的科目,该文就中职生的程序设计能力的培养提出了一些见解和做法,以就业为导向,要求教师要从更新教学理念入手,引入做中学,做中教的教学理念,改进教学方法和教学评价模式,深入探究中职生程序设计能力培养的可行性,通过各种学习渠道挖掘学生编写程序设计能力和天赋,培养和提高学生的程序设计能力。 相似文献
1000.
《Java程序设计》是石家庄邮电职业技术学院2007年确立的一批重点课程之一,通过近年课程建设的具体实践,该课程已在教学内容、教学方法和手段、教学资源、师资队伍等方面取得了成果,为今后精品课程的建设提供了宝贵的经验。 相似文献