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91.
本文讨论了用三维实体结构型技术(CSG)发开模具CAD/CAM系统,并且运用面向对象的分析方法分别建立了零件三维信息及其相互关系的数据结构,由此可以作为开展模具CAD/CAM系统软件的基础。 相似文献
92.
面向对象软件的基本测试单元是类,文中提出了用一种基于代码的测试技术-数据流测试来全面地测试类。对类测试分为3级:单个成员函数的测试;公有成员函数的测试;公有成员函数接口的测试。 相似文献
93.
本文针对一类智能决策支持系统中,基于模型行为仿真以实现解题过程自动化的需要,提出对模型对象行为的一阶谓词演算型表达和面向对象型模型处理过程的形式化体系。将问题自动求解过程转化为逻辑运算过程,通过归结反演求取问题的解。文中给出一个应用实例。 相似文献
94.
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95.
Economic globalization leads to complex decentralized company structures calling for the extensive use of distributed IT-systems.
The business processes of a company have to reflect these changes of infrastructure. In particular, due to new electronic
applications and the inclusion of a higher number of—potentially unknown—persons, the business processes are more vulnerable
against malicious attacks than traditional processes. Thus, a business should undergo a security analysis. Here, the vulnerabilities
of the business process are recognized, the risks resulting from the vulnerabilities are calculated, and suitable safeguards
reducing the vulnerabilities are selected. Unfortunately, a security analysis tends to be complex and affords expensive security
expert support. In order to reduce the expense and to enable domain experts with in-depth insight in business processes but
with limited knowledge about security to develop secure business processes, we developed the framework MoSSBP facilitating the handling of business process security requirements from their specification to their realization. In particular,
MoSS
BP
provides graphical concepts to specify security requirements, repositories of various mechanisms enforcing the security requirements,
and a collection of reference models and case studies enabling the modification of the business processes. In this paper,
the MoSS
BP
-framework is presented. Additionally, we introduce a tool supporting the MoSSBP-related security analysis of business processes and the incorporation of safeguards. This tool is based on object-oriented
process models and acts with graph rewrite systems. Finally, we clarify the application of the MoSSBP-framework by means of a business process for tender-handling which is provided by anonymity-preserving safeguards.
Peter Herrmann studied computer science at the University of Karlsruhe, Germany (diploma in 1990). Afterwards, he worked as a Ph.D. student
(doctorate in 1997) and postdoctoral researcher in the Computer Networks and Distributed Systems Group of the Computer Science
Department at the University of Dortmund, Germany. Since 2005 he is a full professor for formal methods at the Department
for Telematics of the Norwegian University of Science and Technology (NTNU) in Trondheim, Norway. His research interests include
the formal-based development of networked systems and the engineering of distributed services. Moreover, he is interested
in security and trust aspects of component structured distributed software.
Gaby Herrmann studied computer science at the University of Karlsruhe, Germany (diploma in 1991). Afterwards, she worked as a researcher
in the Communication Group and the Information Systems Group at University of Duisburg-Essen (Doctorate in 2001, topic: security
of business processes). Since 2000 she works as executive secretary at the Department of Economics, Business Studies and Computer
Sciences at the same university. 相似文献
96.
97.
The goal of this paper is to investigate the relation between object-oriented design choices and defects in software systems, with focus on a real-time telecommunication domain. The design choices are measured using the widely accepted metrics suite proposed by Chidamber and Kemerer for object oriented languages [S.R. Chidamber, C.F. Kemerer, A metrics suite for object oriented design, IEEE Transactions on Software Engineering 20 (6) (1994) 476-493].This paper reports the results of an extensive case study, which strongly reinforces earlier, mainly anecdotal, evidence that design aspects related to communication between classes can be used as indicators of the most defect-prone classes.Statistical models applicable for the non-normally distributed count data are used, such as Poisson regression, negative binomial regression, and zero-inflated negative binomial regression. The performances of the models are assessed using correlations, dispersion coefficients and Alberg diagrams.The zero-inflated negative binomial regression model based on response for a class shows the best overall ability to describe the variability of the number of defects in classes. 相似文献
98.
99.
100.
MATLAB与Java的联合应用研究 总被引:5,自引:0,他引:5
科学与工程领域经常涉及网络环境下的工程计算问题。MATLAB具有很强的数值计算能力,Java是目前普遍使用的网络应用开发工具。本文研究了工程计算问题中的MATLAB与Java联合途径,提出二者联合应用的三种方法。研究与应用表明,这些方法能够将MATLAB的运算能力与Java的网络开发功能结合起来,实现二者的优势互补,拓宽应用领域,增强应用程序的处理能力,很好地解决网络环境下的工程计算问题。由于三种方法各有所长,在实际应用中要根据具体问题和要求的不同进行合适的选择。 相似文献