Home About us Contact
|
Home About us Contact | ||
|
|
||
Object-oriented Design (object-oriented + design)
Selected AbstractsAn object-oriented design and reference implementation for web-based instructional softwareCOMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 1 2005Shrimalini Jayaramaraja Abstract There is an increasing global demand for web-based instructional software. The functional requirements and object-oriented design for a typical web-based instructional system are presented here using the Unified Modeling Language (UML). An interactive, reusable and scalable reference implementation of this model is developed in Java. Several deployment strategies are discussed. © 2005 Wiley Periodicals, Inc. Comput Appl Eng Educ 13: 26,39, 2005; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20027 [source] A Distributed Object-Oriented Finite-Element Analysis Program ArchitectureCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 5 2001Hung-Ming Chen This article presents a distributed object-oriented design for a nonlinear finite-element analysis using the message-passing paradigm and a single-program, multiple-data scheme. The architecture is an extension of an existing sequential object-oriented architecture. The design recognizes the costly communication startup time penalty by attempting to minimize the frequency of communications. This is facilitated by distributing not only the elements in the model but also their associated nodes and mapping between the degrees of freedom and the analytical equations of equilibrium. The proposed object design was implemented and tested on a nonlinear static pushover analysis of three moment-resisting frames. [source] Two-dimensional anisotropic Cartesian mesh adaptation for the compressible Euler equationsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 11 2004W. A. Keats Abstract Simulating transient compressible flows involving shock waves presents challenges to the CFD practitioner in terms of the mesh quality required to resolve discontinuities and prevent smearing. This paper discusses a novel two-dimensional Cartesian anisotropic mesh adaptation technique implemented for transient compressible flow. This technique, originally developed for laminar incompressible flow, is efficient because it refines and coarsens cells using criteria that consider the solution in each of the cardinal directions separately. In this paper, the method will be applied to compressible flow. The procedure shows promise in its ability to deliver good quality solutions while achieving computational savings. Transient shock wave diffraction over a backward step and shock reflection over a forward step are considered as test cases because they demonstrate that the quality of the solution can be maintained as the mesh is refined and coarsened in time. The data structure is explained in relation to the computational mesh, and the object-oriented design and implementation of the code is presented. Refinement and coarsening algorithms are outlined. Computational savings over uniform and isotropic mesh approaches are shown to be significant. Copyright © 2004 John Wiley & Sons, Ltd. [source] FOX, `free objects for crystallography': a modular approach to ab initio structure determination from powder diffractionJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 6 2002Vincent Favre-Nicolin A new program has been developed for ab initio crystal structure determination from powder diffraction data (X-ray and neutron). It uses global-optimization algorithms to solve the structure by performing trials in direct space. It is a modular program, capable of using several criteria for evaluating each trial configuration (e.g. multi-pattern). It is also modular in the description of the crystal content, with the possibility of describing building blocks in the sample, such as polyhedra or molecules, and with automatic adaptive handling of special positions and sharing of identical atoms between neighbouring building blocks. It can therefore find the correct structure without any assumption about the connectivity of the building blocks and is suitable for any kind of material. Several optimization algorithms (simulated annealing, parallel tempering) are available, with the possibility of choosing the convergence criterion as a combination of available cost functions. This program is freely available for Linux and Windows platforms; it is also fully `open source', which, combined with an object-oriented design and a complete developer documentation, ensures its future evolution. [source] Search-based refactoring: an empirical studyJOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 5 2008Mark O'Keeffe Abstract Object-oriented systems that undergo repeated addition of functionality commonly suffer a loss of quality in their underlying design. This problem must often be remedied in a costly refactoring phase before further maintenance programming can take place. Recently search-based approaches to automating the task of software refactoring, based on the concept of treating object-oriented design as a combinatorial optimization problem, have been proposed. However, because search-based refactoring is a novel approach it is yet to be established as to which search techniques are most suitable for the task. In this paper we report the results of an empirical comparison of simulated annealing (SA), genetic algorithms (GAs) and multiple ascent hill-climbing (HCM) in search-based refactoring. A prototype automated refactoring tool is employed, capable of making radical changes to the design of an existing program in order that it conforms more closely to a contemporary quality model. Results show HCM to outperform both SA and GA over a set of five input programs. Copyright © 2008 John Wiley & Sons, Ltd. [source] Experience report on using object-oriented design for software maintenanceJOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 3 2007Norman F. Schneidewind Abstract We experimented with modifying the existing object-oriented (OO) design and C++ code of a software reliability model. Our purpose was to assess the efficacy of OO methods for performing maintenance on mathematical software, using a real-world system (NASA Space Shuttle flight software) to illustrate the approach. In this process, we used variants of UML diagrams to modify our design. We found that although a top-down approach to software maintenance is normally a good idea, it was still necessary to modify the design once the realities of what could be accomplished in the C++ code came to light. As reliability and maintenance are intimately related, we developed reliability risk analysis to show how maintenance changes to our design and code could be used to measure risk. Another maintenance enhancement to the design and code is the use of reliability parameter analysis to assess, in the advance of prediction, the reliability of a set of software releases. We believe this is the first evaluation of software maintenance using OO methods. Copyright © 2007 John Wiley & Sons, Ltd. [source] | ||||||||||