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61.
分析UML模型一致性检测的研究意义,以及UML类图推理的研究现状,提出一种基于OWL本体的UML类图推理方案.研究UML类图向OWL本体转换的映射规则,给出UML类图包含关系、可满足性、等价关系和相离关系的判断方法及其推理规则.利用Jena推理机制实现了UML类图包含关系、可满足性、等价关系和相离关系的推理.  相似文献   
62.
A comprehensive quality model for service-oriented systems   总被引:2,自引:0,他引:2  
In a service-oriented system, a quality (or Quality of Service) model is used (i) by service requesters to specify the expected quality levels of service delivery; (ii) by service providers to advertise quality levels that their services achieve; and (iii) by service composers when selecting among alternative services those that are to participate in a service composition. Expressive quality models are needed to let requesters specify quality expectations, providers advertise service qualities, and composers finely compare alternative services. Having observed many similarities between various quality models proposed in the literature, we review these and integrate them into a single quality model, called QVDP. We highlight the need for integration of priority and dependency information within any quality model for services and propose precise submodels for doing so. Our intention is for the proposed model to serve as a reference point for further developments in quality models for service-oriented systems. To this aim, we extend the part of the UML metamodel specialized for Quality of Service with QVDP concepts unavailable in UML.
Stéphane FaulknerEmail:

Ivan J. Jureta   has, after graduating, summa cum laude, received the Master in Management and Master of International Management, respectively, at the Université de Louvain, Belgium, and the London School of Economics, both in 2005. He is currently completing his Ph.D. thesis at the University of Namur, Belgium, under Prof. Stéphane Faulkner’s supervision. His thesis focuses on quality management of adaptable and open service-oriented systems enabling the Semantic Web. Caroline Herssens   received a Master Degree in Computer Science in 2005 at the Université de Louvain. In 2006, she graduated a Master in Business and Administration from the University of Louvain, with a supply chain management orientation. She is currently a teaching and research assistant and has started a Ph.D. thesis at the information systems research unit at Université de Louvain. Her research interests comprise service-oriented computing, conceptual modeling and information systems engineering. Stéphane Faulkner   is an Associate Professor in Technologies and Information Systems at the University of Namur (FUNDP) and an Invited Professor at the Louvain School of Management of the Université de Louvain (UCL). His current research interests revolve around requirements engineering and the development of modeling notations, systematic methods and tool support for the development of multi-agent systems, database and information systems.   相似文献   
63.
安全性作为软件系统的重要属性,越来越受到人们的重视.在软件开发的早期对安全性进行评估,对软件的质量控制和成本控制有着重要意义.当前的软件安全性评估主要依靠专家评审,结果的客观性及准确性常常受到专家主观意见的影响.通过使用通用知识作为评估依据,提出一种可以对UML顺序图形式的软件设计文档进行自动化分析的方法,可以发现软件设计中潜在的安全性漏洞.该方法可以减少结果中的主观性,同时,通过基于该方法的辅助工具的使用,可以大大提高评估效率.  相似文献   
64.
A computational model is a computer program, which attempts to simulate an abstract model of a particular system. Computational models use enormous calculations and often require supercomputer speed. As personal computers are becoming more and more powerful, more laboratory experiments can be converted into computer models that can be interactively examined by scientists and students without the risk and cost of the actual experiments. The future of programming is concurrent programming. The threaded programming model provides application programmers with a useful abstraction of concurrent execution of multiple tasks. The objective of this release is to address the design of architecture for scientific application, which may execute as multiple threads execution, as well as implementations of the related shared data structures.

New version program summary

Program title: GrowthCPCatalogue identifier: ADVL_v4_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADVL_v4_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.: 32 269No. of bytes in distributed program, including test data, etc.: 8 234 229Distribution format: tar.gzProgramming language: Free Object PascalComputer: multi-core x64-based PCOperating system: Windows XP, Vista, 7Has the code been vectorised or parallelized?: NoRAM: More than 1 GB. The program requires a 32-bit or 64-bit processor to run the generated code. Memory is addressed using 32-bit (on 32-bit processors) or 64-bit (on 64-bit processors with 64-bit addressing) pointers. The amount of addressed memory is limited only by the available amount of virtual memory.Supplementary material: The figures mentioned in the “Summary of revisions” section can be obtained here.Classification: 4.3, 7.2, 6.2, 8, 14External routines: Lazarus [1]Catalogue identifier of previous version: ADVL_v3_0Journal reference of previous version: Comput. Phys. Comm. 181 (2010) 709Does the new version supersede the previous version?: YesNature of problem: Reflection high-energy electron diffraction (RHEED) is an important in-situ analysis technique, which is capable of giving quantitative information about the growth process of thin layers and its control. It can be used to calibrate growth rate, analyze surface morphology, calibrate surface temperature, monitor the arrangement of the surface atoms, and provide information about growth kinetics. Such control allows the development of structures where the electrons can be confined in space, giving quantum wells or even quantum dots. In order to determine the atomic positions of atoms in the first few layers, the RHEED intensity must be measured as a function of the scattering angles and then compared with dynamic calculations. The objective of this release is to address the design of architecture for application that simulates the rocking curves RHEED intensities during hetero-epitaxial growth process of thin films.Solution method: The GrowthCP is a complex numerical model that uses multiple threads for simulation of epitaxial growth of thin layers. This model consists of two transactional parts. The first part is a mathematical model being based on the Runge–Kutta method with adaptive step-size control. The second part represents first-principles of the one-dimensional RHEED computational model. This model is based on solving a one-dimensional Schrödinger equation. Several problems can arise when applications contain a mixture of data access code, numerical code, and presentation code. Such applications are difficult to maintain, because interdependencies between all the components cause strong ripple effects whenever a change is made anywhere. Adding new data views often requires reimplementing a numerical code, which then requires maintenance in multiple places. In order to solve problems of this type, the computational and threading layers of the project have been implemented in the form of one design pattern as a part of Model-View-Controller architecture.Reasons for new version: Responding to the users? feedback the Growth09 project has been upgraded to a standard that allows the carrying out of sample computations of the RHEED intensities for a disordered surface for a wide range of single- and epitaxial hetero-structures. The design pattern on which the project is based has also been improved. It is shown that this model can be effectively used for multithreaded growth simulations of thin epitaxial layers and corresponding RHEED intensities for a wide range of single- and hetero-structures. Responding to the users? feedback the present release has been implemented using a well-documented free compiler [1] not requiring the special configuration and installation additional libraries.Summary of revisions:
  • 1. 
    The logical structure of the Growth09 program has been modified according to the scheme showed in Fig. 1.1 The class diagram in Fig. 11 is a static view of the main platform-specific elements of the GrowthCP architecture. Fig. 21 provides a dynamic view by showing the creation and destruction simplistic sequence diagram for the process.
  • 2. 
    The program requires the user to provide the appropriate parameters in the form of a knowledge base for the crystal structures under investigation. These parameters are loaded from the parameters.ini files at run-time. Instructions to prepare the .ini files can be found in the new distribution.
  • 3. 
    The program enables carrying out different growth models and one-dimensional dynamical RHEED calculations for the fcc lattice with basis of three-atoms, fcc lattice with basis of two-atoms, fcc lattice with single atom basis, Zinc-Blende, Sodium Chloride, and Wurtzite crystalline structures and hetero-structures, but yet the Fourier component of the scattering potential in the TRHEEDCalculations.crystPotUgXXX() procedure can be modified and implemented according to users? specific application requirements. The Fourier component of the scattering potential of the whole crystalline hetero-structures can be determined as a sum of contributions coming from all thin slices of individual atomic layers. To carry out one-dimensional calculations of the scattering potentials, the program uses properly constructed self-consistent procedures.
  • 4. 
    Each component of the system shown in Figs. 11 and 21 is fully extendable and can easily be adapted to new changeable requirements. Two essential logical elements of the system, i.e. TGrowthTransaction and TRHEEDCalculations classes, were designed and implemented in this way for them to pass the information to themselves without the need to use the data-exchange files given. In consequence each of them can be independently modified and/or extended. Implementing other types of differential equations and the different algorithm for solving them in the TGrowthTransaction class does not require another implementation of the TRHEEDCalculations class. Similarly, implementing other forms of scattering potential and different algorithm for RHEED calculation stays without the influence on the TGrowthTransaction class construction.
Unusual features: The program is distributed in the form of main project GrowthCP.lpr, with associated files, and should be compiled using Lazarus IDE. The program should be compiled with English/USA regional and language options.Running time: The typical running time is machine and user-parameters dependent.References:
  • [1] 
    http://sourceforge.net/projects/lazarus/files/.
  相似文献   
65.
Association redefinition is a UML construct that permits us to define an association end more specifically in a particular context. Concretely, it allows specifying some additional participation and cardinality constraints on the association. Association refinements, which have been studied and used by many authors in conceptual modelling languages prior to UML, are closely related to association redefinitions. They also permit to refine the ends of an association adding participation and cardinality constraints. In this paper, we analyze and compare the semantics of both concepts and propose to extend the semantics of association redefinitions in UML to cover all the constraints that may be expressed by association refinements in other conceptual modelling languages. Additionally, we present how to integrate previous results on validation of association refinements to UML and how to generate code for a relational technology platform. Finally, we provide a prototype tool to verify the feasibility of the approach.  相似文献   
66.
One of the more tedious and complex tasks during the specification of conceptual schemas (CSs) is modeling the operations that define the system behavior. This paper aims to simplify this task by providing a method that automatically generates a set of basic operations that complement the static aspects of the CS and suffice to perform all typical life-cycle create/update/delete changes on the population of the elements of the CS. Our method guarantees that the generated operations are executable, i.e. their executions produce a consistent state wrt the most typical structural constraints that can be defined in CSs (e.g. multiplicity constraints). In particular, our method takes as input a CS expressed as a Unified Modeling Language (UML) class diagram (optionally defined using a profile to enrich the specification of associations) and generates an extended version of the CS that includes all necessary operations to start operating the system. If desired, these basic operations can be later used as building blocks for creating more complex ones. We show the formalization and implementation of our method by means of model-to-model transformations. Our approach is particularly relevant in the context of Model Driven Development approaches.  相似文献   
67.
对于MDA横切于核心业务逻辑的关注点对封装的破坏的问题,本文给出把AOP引入到MDA的扩展策略和主要方法,并对不同的扩展策略进行了比较。  相似文献   
68.
CAPP与PDM集成接口分析   总被引:1,自引:0,他引:1  
以PDM为平台进行 企业CIMS建设是现阶段企业易于接受并 一种集成模式。在这种模式中CAPP成为影响PDM集成的关键因素。文中结合实际项目,在综合考虑信息共享、并行设计等技术因素的基础上,详细分析了CAPP与PDM的集成接口,并对接口主要对象模型进行了UML描 。文中最提出了妥善解决要成问题的方法。  相似文献   
69.
UML在分布式系统中的应用与研究   总被引:5,自引:0,他引:5  
UML(Unified  Modeling  Language)是一种标准的、功能强大的建模语言。ISO RM-ODP(ISO开放分布式处理参考模型)为开放、灵活的分布式系统提供了主框架。文章提出了一种用UML为ODP系统建模的方法,它以ODP的概念和UML的符号为基础。  相似文献   
70.
三值关联规则在不确定性知识表示及推理性的应用   总被引:1,自引:0,他引:1  
动态分类是指对象所属的类可随时间而变化。在进行系统分析和软件开发中,需要真实地描述研究对象在其生命周期中的变化,动态分类正是这样一种机制。但是由于许多面向对象程序设计语言都不支持动态分类,因此需要用别的方法来描述动态分类,文中给出了用UML表达动态分类的四种机制,并对这四种机制进行了比较。  相似文献   
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