A prototype persistence system based on the nitrO reflective system demonstrates that computational reflection is a suitable technique for dynamically and transparently adapting any application's persistence attri...
详细信息
A prototype persistence system based on the nitrO reflective system demonstrates that computational reflection is a suitable technique for dynamically and transparently adapting any application's persistence attributes, following the separation-of-concerns principle. Because computational reflection offers the runtime customization of language semantics, it lets developers combine programming language and database management systems into a single computational model.
It is well known that vector-tenser notation is a compact and natural language for the mathematical formulation of continuum mechanics problems. Here we describe the application of vector technique to numerical simula...
详细信息
It is well known that vector-tenser notation is a compact and natural language for the mathematical formulation of continuum mechanics problems. Here we describe the application of vector technique to numerical simulation starting with a mathematical formulation. We provide an efficient numerical scheme and furnish an implementation as a computer program. As a result (in comparison with traditional "component" form), the two last steps are significantly simplified, especially for multidimensional problems with various boundary conditions in irregular geometries where nonorthogonal meshes are applied. Therefore, more attention can be focused on the physical nature of problems. Apart from the cleaner syntax, vector notation conserves the structure of traditional numerical algorithms and solves multidimensional problems with minimum additional programming effort. Complex practical applications of this technique are described as well. (C) 2001 Academic Press.
The article presents a method for constructing a model of an object-oriented program in terms of multilabeled Petri nets. Only encapsulation-one of the three concepts of object-oriented paradigm-is considered. To mode...
详细信息
The article presents a method for constructing a model of an object-oriented program in terms of multilabeled Petri nets. Only encapsulation-one of the three concepts of object-oriented paradigm-is considered. To model a different aspects of encapsulation a Petri net structured object is proposed. It consists of a Petri net defining its behavior and a set of organized access points specifying its structural properties. Formal composition operations to construct a program model from the models of its methods, classes, objects, functions, and modules are introduced and a source code translation algorithm to Petri net representation is proposed. A special section of the article considers in detail a process of model construction of a real object-oriented program (OOP). Source code of the program, figures with Petri net objects modeling different elements of the program and the resulting model of the program are presented.
Software evolution is an important activity in the life cycle of a modern software system. In the process of software evolution, the repair of historical defects and the increasing demands may introduce new defects. T...
详细信息
Software evolution is an important activity in the life cycle of a modern software system. In the process of software evolution, the repair of historical defects and the increasing demands may introduce new defects. Therefore, evolution-oriented defect prediction has attracted much attention of researchers in recent years. At present, some researchers have proposed the process metrics to describe the characteristics of software evolution. However, compared with the traditional software defect prediction methods, the research on evolution-oriented defect prediction is still inadequate. Based on the evolution data of object-oriented programs, this study presented two new process metrics from the defect rates of historical packages and the change degree of classes. To show the effectiveness of the proposed process metrics, the authors made comparisons with the code metrics and other process metrics. An empirical study was conducted on 33 versions of nine open-source projects. The results showed that adding the proposed process metrics could improve the performance of evolution-oriented defect prediction effectively.
The paper presents the application of object-oriented modeling techniques to control software development for complex manufacturing systems, with particular focus on case studies taken from the packaging industry and ...
详细信息
The paper presents the application of object-oriented modeling techniques to control software development for complex manufacturing systems, with particular focus on case studies taken from the packaging industry and design patterns that can be abstracted from such case studies. The proposed methodology for control software modeling and implementation is based on a practical approach refined on the basis of on-the-field experience and interactions with control engineers involved in the development projects. The final objective of the paper is to review and analyze patterns for the solution of design and implementation issues that typically arise in the considered application domain. (C) 2012 Elsevier Ltd. All rights reserved.
This contribution presents a methodology to efficiently obtain the numerical and computer solution of dynamic power systems with high penetration of wind turbines. Due to the excessive computational load required to s...
详细信息
This contribution presents a methodology to efficiently obtain the numerical and computer solution of dynamic power systems with high penetration of wind turbines. Due to the excessive computational load required to solve the abc models that represent the behavior of the wind turbines, a parallel processing scheme is proposed to enhance the solution of the overall system. Case studies are presented which demonstrate the effectiveness and applications of the proposed methodology. Copyright (C) 2012 John Wiley & Sons, Ltd.
The efficiency of object-oriented programs has become a point of great interest, One necessary factor for program efficiency is the optimization techniques involved. This paper presents the performance of several vari...
详细信息
The efficiency of object-oriented programs has become a point of great interest, One necessary factor for program efficiency is the optimization techniques involved. This paper presents the performance of several variations of a given C++ program and compares them with a version that uses no object-oriented features, Our result indicates that some object-oriented features in C++ are not well optimized in current C++ compilers. We thus discuss some code optimization techniques that can improve the efficiency based on the given C++ program.
An object-oriented microwave circuit simulation environment is described. The design of the program is intended to offer flexibility,without sacrificing efficiency. Recent developments in object-oriented techniques an...
详细信息
An object-oriented microwave circuit simulation environment is described. The design of the program is intended to offer flexibility,without sacrificing efficiency. Recent developments in object-oriented techniques and in C++ compilers are used to obtain a flexible and robust system ideally suited to the development of a global modeling strategy for the integration of circuit, field, thermal, and mechanical analyses. The simulation of spatial power combining systems is used as a vehicle to illustrate the architectural developments of the system. (C) 2000 John Wiley & Sons, Inc.
The authors present a suite to assist in the creation of musical pieces, whose foundation lies on fractals, fuzzy logic and expert systems. Even though algorithmic music has been explored, some gaps still exist. The f...
详细信息
The authors present a suite to assist in the creation of musical pieces, whose foundation lies on fractals, fuzzy logic and expert systems. Even though algorithmic music has been explored, some gaps still exist. The favored approach has consisted in mapping numbers to notes to create appealing pieces. This, we contend, is a necessary but not a sufficient condition. Our suite, besides the necessary mapping, possesses the following advantages. First, it is possible to define notes, tempos, and notes durations. Notes evolve according to the selected fractal. Tempos and durations can remain fixed or they also can follow a fractal. Second, it is possible to translate the resultant fractal notes into notes belonging to a musical scale. This is done by firing appropriate rules in a rule base. Third, interpretation templates are provided. Also, melodies or harmonies are available. The suite currently contains several known fractal systems, and we also proposed one dynamical, recursive computation based on Mamdani fuzzy rule bases. The suite we present helps promoting and monitoring the creative process of composing musical scores. The actual implementation of the suite was done on the Java language. (C) 2012 Elsevier Ltd. All rights reserved.
This study develops and empirically tests the idea that the impact of structural complexity on perfective maintenance of object-oriented software is significantly determined by the team strategy of programmers (indepe...
详细信息
This study develops and empirically tests the idea that the impact of structural complexity on perfective maintenance of object-oriented software is significantly determined by the team strategy of programmers (independent or collaborative). We analyzed two key dimensions of software structure, coupling and cohesion, with respect to the maintenance effort and the perceived ease-of-maintenance by pairs of programmers. Hypotheses based on the distributed cognition and task interdependence theoretical frameworks were tested using data collected from a controlled lab experiment employing professional programmers. The results show a significant interaction effect between coupling, cohesion, and programmer team strategy on both maintenance effort and perceived ease-of-maintenance. Highly cohesive and low-coupled programs required lower maintenance effort and were perceived to be easier to maintain than the low-cohesive programs and high-coupled programs. Further, our results would predict that managers who strategically allocate maintenance tasks to either independent or collaborative programming teams depending on the structural complexity of software could lower their team's maintenance effort by as much as 70 percent over managers who use simple uniform resource allocation policies. These results highlight the importance of achieving congruence between team strategies employed by collaborating programmers and the structural complexity of software.
暂无评论