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Andrzej Daniluk 《Computer Physics Communications》2010,181(3):709-710
Modelling, simulation, and visualisation together create the third branch of human knowledge on equal footing with theory and experiment. Model-Driven Development (MDD) has been proposed as a means to support the software development process through the use of a model-centric approach. The objective of this paper is to address the design of an architecture for scientific application that may execute as multithreaded computations, as well as implementations of the related shared data structures.
New version program summary
Program title: Growth09Catalogue identifier: ADVL_v3_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADVL_v3_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.: 30 940No. of bytes in distributed program, including test data, etc.: 3 119 488Distribution format: tar.gzProgramming language: Embarcadero DelphiComputer: Intel Core Duo-based PCOperating system: Windows XP, Vista, 7RAM: more than 1 GBClassification: 4.3, 7.2, 6.2, 8, 14Catalogue identifier of previous version: ADVL_v2_1Journal reference of previous version: Comput. Phys. Comm. 180 (2009) 1219Subprograms used:Cat Id Title Reference ADUY_v4_0 RHEED1DProcess CPC 999 (9999) 9999 - Full-size table
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Andrzej Daniluk 《Computer Physics Communications》2010,181(3):707-708
Scientific computing is the field of study concerned with constructing mathematical models, numerical solution techniques and with using computers to analyse and solve scientific and engineering problems. Model-Driven Development (MDD) has been proposed as a means to support the software development process through the use of a model-centric approach. This paper surveys the core MDD technology that was used to develop an application that allows computation of the RHEED intensities dynamically for a disordered surface.
New version program summary
Program title: RHEED1DProcessCatalogue identifier: ADUY_v4_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADUY_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.: 31 971No. of bytes in distributed program, including test data, etc.: 3 039 820Distribution format: tar.gzProgramming language: Embarcadero C++ BuilderComputer: Intel Core Duo-based PCOperating system: Windows XP, Vista, 7RAM: more than 1 GBClassification: 4.3, 7.2, 6.2, 8, 14Catalogue identifier of previous version: ADUY_v3_0Journal reference of previous version: Comput. Phys. Comm. 180 (2009) 2394Does the new version supersede the previous version?: NoNature of problem: An application that implements numerical simulations should be constructed according to the CSFAR rules: clear and well-documented, simple, fast, accurate, and robust. A clearly written, externally and internally documented program is much easier to understand and modify. A simple program is much less prone to error and is more easily modified than one that is complicated. Simplicity and clarity also help make the program flexible. Making the program fast has economic benefits. It also allows flexibility because some of the features that make a program efficient can be traded off for greater accuracy. Making the program fast also has the benefit of allowing longer calculations with better resolution. The compromise between speed and accuracy has always posted one of the most troublesome challenges for the programmer. Almost all advances in numerical analysis have come about trying to reach these twin goals. Change in the basic algorithms will give greater improvements in accuracy and speed than using special numerical tricks or changing programming language. A robust program works correctly over a broad spectrum of input data.Solution method: The computational model of the program is based on the use of a dynamical diffraction theory in which the electrons are taken to be diffracted by a potential, which is periodic in the dimension perpendicular to the surface. In the case of a disordered surface we can use the proportional model of the scattering potential, in which the potential of a partially filled layer is taken to be the product of the coverage of this layer and the potential of a fully filled layer:3.
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Andrzej Daniluk 《Computer Physics Communications》2011,182(6):1389-1390
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.
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http://sourceforge.net/projects/lazarus/files/.
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Performance analysis and verification of safety communication protocol are important techniques during protocol development process. In order to meet the requirement of safety, an advanced safety communication protocol is proposed to improve the protocol in EURORADIO. Among the improved protocol, the following two elements are added: (1) advanced scheme of establishment of safety connection. (2) double serial number replaces time stamp. The performance analysis related to safety of the advanced protocol and protocol in EURORADIO is given by Colored Petri Net (CPN) model through simulation. The analysis results verify that the advanced protocol has superior performance. 相似文献
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Existing techniques for developing large scale complex engineering systems are predominantly software based and use Unified Modeling Language (UML). This leads to difficulties in model transformation, analysis, validation, verification and automatic code generation. Currently no general frameworks are available to bridge the concept-code gap rampant in design and development of complex, software-intensive mechatronic systems called cyber-physical systems. To fill this gap and provide an alternative approach to Object Management Group’s UML/SysML/OCL combination, we propose: Bond Graph based Unified Meta-Modeling Framework (BG-UMF). BG-UMF is a practical and viable alternative and uses a novel hybrid approach based on model unification and integration. The focus is on conceptual design and development of executable models for large systems. The viability of the framework is demonstrated through an application scenario: conceptual design and development of a navigation and control system for a rotor-craft UAV. 相似文献
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Modeling and verification of a telecommunication application using live sequence charts and the Play-Engine tool 总被引:1,自引:0,他引:1
We apply the scenario-based approach to modeling, via the language of live sequence charts (LSCs) and the Play-Engine tool
to a real-world complex telecommunication service, . It allows a user to call for help from a doctor, the fire brigade, a car maintenance service, etc. These kinds of services
are built on top of an embedded platform, using both new and existing service components, and their complexity stems from
their distributed architecture, the various time constraints they entail, and their rapidly evolving underlying systems. A
well known problem in this class of telecommunication applications is that of feature interaction, whereby a new feature might
cause problems in the execution of existing features. Our approach provides a methodology for high-level modeling of telecommunication
applications that can help in detecting feature interaction at early development stages. We exhibit the results of applying
the methodology to the specification, animation and formal verification of the Depannage service.
相似文献
Hillel Kugler (Corresponding author)Email: |
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输送系统的UML建模、优化与实现 总被引:1,自引:0,他引:1
将面向对象方法引入输送系统的建模和分析过程,采用统一建模语言UML对系统的功能、对象结构、行为和活动以及实现方式等建立了一整套模型。UML模型可以采用面向对象语言快速实现,按照模块化结构,使用PLC编程语言也可实现面向对象编程。采用UML对输送系统进行分析可将系统实现的复杂性降低,有利于系统的分析和设计,系统的优化算法可以在此基础上进一步研究和实现。(以一个工程为实例,说明了相对于传统的顺控方案,以UML模型为基础的输送系统在开发和维护、扩充和代码重用等方面具有显著优势,UML在顺序控制系统中具有广阔的应用和研究前景。) 相似文献
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随着嵌入式系统规模、复杂度和性能需求的提升,嵌入式系统开发的重点从代码级提前到模型级,模型驱动体系结构成为嵌入式系统开发的主流。统一建模语言(UML)和结构分析和设计语言(AADL)是模型驱动系统工程的标准,从方法、扩展机制和应用领域三个方面对两者进行研究和比较,讨论模型分析、模型转换等相关技术。最后,探讨了UML和AADL的发展与研究方向 相似文献
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结合UML和RAISE的软件开发方法研究 总被引:2,自引:0,他引:2
面向对象方法形象、直观、使用方便,但难以消除二义性。形式化方法严密、可靠、可验证,但软件规约不直观,不符合开发人员的使用习惯,探讨一种结合面向对象方法UML和形式化方法RAISE的软件开发方法。 相似文献
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基于UML的用户管理系统分析与设计 总被引:1,自引:0,他引:1
对UML产生的背景及其基本模型进行了阐述,以用户管理系统的UML建模为背景,探索了基于UML的管理信息系统建模及UML中多种模型图的使用方法,并对传统的访问控制模型做了改进。最后对系统效率进行了验证。 相似文献
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