Many tools for object-oriented software design focus on assisting individuals in creating UML models for documentation and implementation purposes. Since software design is a highly collaborative activity, one must as...
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ISBN:
(纸本)159593491X
Many tools for object-oriented software design focus on assisting individuals in creating UML models for documentation and implementation purposes. Since software design is a highly collaborative activity, one must ask whether the requirements for facilitating collaborative design are *** report on a study of design teams, focusing on their use of notations and artifacts. Our findings highlight the unique characteristic of the use of UML in these settings and emphasize the importance of context and relations between artifacts over the details of specific artifacts.
The four-dimensional ensemble variational (4DEnVar) formulation has received considerable attention during recent years, especially at numerical weather prediction centres that are (or were) relying on a 3D/4D-Var for...
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The four-dimensional ensemble variational (4DEnVar) formulation has received considerable attention during recent years, especially at numerical weather prediction centres that are (or were) relying on a 3D/4D-Var formalism for their data assimilation systems. Since 4DEnVar background-error covariances are, by construction, given by an ensemble of 4D nonlinear trajectories, an important issue is the way in which to build this ensemble. The use of an ensemble of perturbed 4DEnVar to generate the ensemble is a natural approach, but raises difficulties for the input and storage of 4D trajectories. A parallel implementation of such a 4DEnVar ensemble (En-4DEnVar) approach is proposed, with distributed input and storage of ensemble perturbations. It has the benefit of an object-orientedimplementation of 4DEnVar, which has recently been developed at Meteo-France. First results obtained with the French global model Action de Recherche Petite Echelle Grande Echelle (ARPEGE) show that such an approach is efficient and suggest that En-4DEnVar implementations are tractable.
Control software for astronomy matches the ever increasing complexity of new large instrumentation projects. In order to speed the development cycle, object-oriented techniques have been used to generate loosely coupl...
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ISBN:
(纸本)0819454281
Control software for astronomy matches the ever increasing complexity of new large instrumentation projects. In order to speed the development cycle, object-oriented techniques have been used to generate loosely coupled software objects and larger scale components that can be reused in future projects. Such object-orientedsystems provide for short development cycles which can respond to changing requirements and allow for extension. The Unified Modeling Language (UML) has been used for the analysis, design and implementation of this software. A distributed system is supported by the use of an object broker such as CORBA. These techniques are being applied to the development of an instrument control system for the UK spectrograph within FMOS (Fiber-fed Multi-object Spectrograph). This is a second generation instrument for the Subaru Telescope of the National Astronomical Observatory of Japan.
The results and new technology proposal of applying object-oriented technologies to embedded control software are discussed in this paper. There exists following obstacles when we apply object-oriented technologies to...
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ISBN:
(纸本)081868383X
The results and new technology proposal of applying object-oriented technologies to embedded control software are discussed in this paper. There exists following obstacles when we apply object-oriented technologies to embedded control software: (1) the analysis and design method for control algorithms find the method of reusing them as software components, and (2) the size reduction method reserving advantages of object-oriented technologies. We propose solutions for each of them. First, we extend the usual object-oriented analysis method. The object structures are identified based on the structure of the control algorithms. Second, we give hierarchical implementation architecture on the small microcomputers. We use assembly language at the lower level of this architecture, and the use of C++ language is restricted only at the upper level. We show this mixed use of object-oriented language with assembly language gives the expected balance of productivity and performance.
The object model has emerged as a useful paradigm for the structuring of distributed systems. This paper gives a brief survey of some current issues in the design and implementation of distributed systems based on the...
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ISBN:
(纸本)0444817913
The object model has emerged as a useful paradigm for the structuring of distributed systems. This paper gives a brief survey of some current issues in the design and implementation of distributed systems based on the object model. The experience gained from the design, implementation, and use of Guide, a distributed object-oriented system for co-operative applications, developed at Bull-IMAG, is presented as an illustration. Some perspectives are discussed in conclusion.
Mesh generation and adaption for solving dopant diffusion in process simulation is a difficult task, complicated by both the moving boundaries of oxide growth [1] and the time dependence of the solutions. For both com...
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Mesh generation and adaption for solving dopant diffusion in process simulation is a difficult task, complicated by both the moving boundaries of oxide growth [1] and the time dependence of the solutions. For both computational and ease of use reasons, automatic mesh generation [2] and discretization error control [3] is desirable. This paper describes an approach based on local error estimates [4] to refine the mesh. The results presented in this paper extend our previous work [5] to two-dimensional problems. The implementation of this approach is done in a process simulator, the Florida object-oriented Process Simulator. Several test cases are described to demonstrate the effectiveness of the algorithms.
In silico materials design is hampered by the computational complexity of Kohn-Sham DFT, which scales cubically with the system size. Owing to the development of new-generation kinetic energy density functionals (KEDF...
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In silico materials design is hampered by the computational complexity of Kohn-Sham DFT, which scales cubically with the system size. Owing to the development of new-generation kinetic energy density functionals (KEDFs), orbital-free DFT (OFDFT) can now be successfully applied to a large class of semiconductors and such finite systems as quantum dots and metal clusters. In this work, we present DFTpy, an open-source software implementing OFDFT written entirely in Python 3 and outsourcing the computationally expensive operations to third-party modules, such as NumPy and SciPy. When fast simulations are in order, DFTpy exploits the fast Fourier transforms from PyFFTW. New-generation, nonlocal and density-dependent-kernel KEDFs are made computationally efficient by employing linear splines and other methods for fast kernel builds. We showcase DFTpy by solving for the electronic structure of a million-atom system of aluminum metal which was computed on a single CPU. The Python 3 implementation is object-oriented, opening the door to easy implementation of new features. As an example, we present a time-dependent OFDFT implementation (hydrodynamic DFT) which we use to compute the spectra of small metal clusters recovering qualitatively the time-dependent Kohn-Sham DFT result. The Python codebase allows for easy implementation of application programming interfaces. We showcase the combination of DFTpy and ASE for molecular dynamics simulations of liquid metals. DFTpy is released under the MIT license. This article is categorized under: Software > Quantum Chemistry Electronic Structure Theory > Density Functional Theory Data Science > Computer Algorithms and Programming
Progressive thinking in software design for the last several years has centered on the use of design patterns. As objectoriented technologies slowly but surely begin to permeate Automatic Test System (ATS) software, ...
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ISBN:
(纸本)0780370945
Progressive thinking in software design for the last several years has centered on the use of design patterns. As objectoriented technologies slowly but surely begin to permeate Automatic Test System (ATS) software, developers are confronted with architectural issues that may be unique to object-orienteddesigns. design patterns offer a guideline for implementing robust architectures using proven techniques. This paper presents four well-known design patterns within the context of ATS software implementations. Although ATS software designs are most often fundamentally process oriented, it is indeed possible to useobjectoriented techniques both for design modeling and implementation.
This paper describes the progress and interim findings of research at the MSI Research Institute at Loughborough University concerned with: consolidating and developing modelling methods and tools, which support the d...
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This paper describes the progress and interim findings of research at the MSI Research Institute at Loughborough University concerned with: consolidating and developing modelling methods and tools, which support the design and implementation of integrated systems. identifying requirements for modelling 'resources' to support the engineering of manufacturing enterprises. The research is funded jointly by the CDP committee of EPSRC and UK industry and is being advanced in conjunction with a consortium of manufacturing user organisations and their software and system suppliers.
Reusable objects components are usually organized in libraries. Improving the reusability of such libraries passes by recognizing that there are two parties to component reuse, with different (sometimes conflicting) i...
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Reusable objects components are usually organized in libraries. Improving the reusability of such libraries passes by recognizing that there are two parties to component reuse, with different (sometimes conflicting) interests: reuse providers, who privilege optimality of implementation (e.g., to minimize redundancy, or to maximize domain content), and reusers, who privilege identification of assets (by optimal domain representation). These conflicting optimality criteria can be mirrored by having separate hierarchies for types (interfaces) and classes (implementation code). In this paper, we propose a `biological metaphor' for object-oriented hierarchies, borrow some taxonomic numerical techniques for hierarchy construction, and apply them to organize classes and types separate and optimally. In particular, we present a mapping mechanism between types and classes;introduce a set of criteria to minimize the number of classes needed to implement a given set of types;use cladistic algorithms to construct minimal hierarchies of either types or classes;and combine these strands into an iterative type/class co-design process. The application of the approach is illustrated by its equivalence in several object-oriented languages. To provide necessary background, we include a brief introduction to biological classification and to cladistics, specially techniques for hierarchy deduction and minimality criteria.
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