Insights are presented, that pertain to the design of object-oriented (OO) finite element analysis (FEA) platforms and were gained from the creation of a particular one for simulating nonlinear (NL) dynamics of flexib...
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Insights are presented, that pertain to the design of object-oriented (OO) finite element analysis (FEA) platforms and were gained from the creation of a particular one for simulating nonlinear (NL) dynamics of flexible reticulated structures. The discussion emphasizes how class hierarchies for OO FEA platforms may be designed to ease implementation, verification, and maintenance while promoting robustness and generality. In particular, a strict division into narrowly interfaced "Model" and "Analysis" parts is proposed for both class and instance hierarchies. A description of the data and methods necessary for FEA of NL dynamics is used to explain the motivation for, practice of, and benefits from employing shallow class hierarchies of co-operating, fine-grained objects, as opposed to the traditional choice of deep class hierarchies of specialized, coarse-grained objects. (C) 2002 Elsevier Science B.V. All rights reserved.
Integrated project support environments (IPSEs) are intended to provide a cohesive and integrated set of tools to support the process of design and development in software engineering projects. Much current research i...
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Integrated project support environments (IPSEs) are intended to provide a cohesive and integrated set of tools to support the process of design and development in software engineering projects. Much current research is concentrated on maximising the degree to which these tools can be integrated. This paper briefly describes the architecture of a prototype IPSE which attempts to achieve a high degree of integration using techniques drawn from the disciplines of intelligent knowledge-based systems, office automation and object-oriented programming. The remainder of the paper deals with the design of a user interface to the IPSE based on direct manipulation. It argues that this provides a consistent and integrated method with which users can interact with the objects in the IPSE's object store.
In this paper we examine the structure of Maxwell equations in order to find clear signposts how to implement finite element software systems. The aim is to recognize the abstractions involved in Maxwell equations and...
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In this paper we examine the structure of Maxwell equations in order to find clear signposts how to implement finite element software systems. The aim is to recognize the abstractions involved in Maxwell equations and to exploit concepts of modern programming techniques, such as object-oriented design, to imitate the abstractions in numerical computing. As mathematics is the machinery to model physical phenomena, it is worth to imitate the same machinery in a software system. If a software system is constructed this way, it is partitioned into distinct components whose function is evident. And that is a basis for a software system that is modifiable and understandable, which are the main goals in software design.
This research article demonstrates the use of constraint networks for modelling the knowledge which is necessary for concurrent product and process design. A knowledge;based constraint network system has been develope...
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This research article demonstrates the use of constraint networks for modelling the knowledge which is necessary for concurrent product and process design. A knowledge;based constraint network system has been developed to maintain design consistency and to support the selection of appropriate manufacturing processes according to pre-defined constraints. A number of constraints related to existing manufacturing facilities and expertise are formulated and modelled using the rules of the knowledge-based toolkit. These constraints are implemented to identify the appropriate machining processes and to show the feasibility of a product's design as it progresses and before making the final prototype. The combination of design and manufacturing constraints enables designers to examine whether the designed part can be manufactured with the available manufacturing facilities. (C) 1998 Elsevier Science Ltd. AII rights reserved.
The real challenge in object standardization is to reconcile diverse views of what an object inherently 'is'. This is harder than agreeing on definitions of secondary characteristics such as type and inheritan...
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The real challenge in object standardization is to reconcile diverse views of what an object inherently 'is'. This is harder than agreeing on definitions of secondary characteristics such as type and inheritance. User interfaces visualize objects as things in two-dimensional space. programming thinks of objects as active things that communicate with each other, such as editors and print programs. Database leans more toward objects as participants in operations, such as documents and printers. Unifying these, in a kind of wave/particle dualism, is intellectually tempting, but leads to its own anomalies. Such fundamental questions need sorting out before we can converge on object standards spanning these disciplines.
This paper presents an efficient method for managing the complexity of software structure by implementing the business rules over the data model using a combination of logical programming and object-oriented programmi...
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This paper presents an efficient method for managing the complexity of software structure by implementing the business rules over the data model using a combination of logical programming and object-oriented programming, concretely applied in a multiphysics application.
As we engineers develop systems, we build models. These models might include business policy guidelines, database schemata, organization charts, class diagrams, and so on. The models span diverse viewpoints and levels...
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As we engineers develop systems, we build models. These models might include business policy guidelines, database schemata, organization charts, class diagrams, and so on. The models span diverse viewpoints and levels of formality. We seldom revisit these models as the enterprise evolves. Often, the modelers themselves have disappeared, and any knowledge that wasn't captured in the specialized models is inaccessible, forgotten, or written off. Engineers use models even more rarely for later Integration efforts, when the systems have been repeatedly patched or, have become brittle and the models themselves are often inaccessible, if even applicable. However, can models be more than tools discarded along the way? Might they provide the enterprise with enduring value? Engineers can use these models to automate some systems integration steps that occur as systems evolve. If models can enable automated integration methods, the overall integration costs will decrease and modeling efforts' enduring value will return because models will become key to a wider segment of the system's life cycle. Our approach to model-driven integration uses a system's existing model's to characterize how the system's resources might be used to fulfill requirements for new interactions. Links-across-views capture the design intent behind legacy systems. They are combined with requirements for new interactions to produce a joint action model. Developers can use the JAM in downstream, automated integration.
Gmat is a C++ program able to compute the rovibrational G matrix in molecules of arbitrary size. This allows the building of arbitrary rovibrational Hamiltonians. In particular, the program is designed to work with th...
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Gmat is a C++ program able to compute the rovibrational G matrix in molecules of arbitrary size. This allows the building of arbitrary rovibrational Hamiltonians. In particular, the program is designed to work with the structural results of potential energy hypersurface mappings computed in computer clusters or computational Grid environments. In the present version, 1.0. the program uses internal coordinates as vibrational coordinates, with the principal axes of inertia as body-fixed system. The main design implements a complete separation of the interface and functional parts of the program. The interface part permits the automatic reading of the molecular structures from the Output files of different electronic structure codes. At present, Gamess and Gaussian output files are allowed. To Such an end, use is made of the object orientation polymorphism characteristic. The functional part computes numerically the derivatives of the nuclear positions respect to the vibrational coordinates. Very accurate derivatives are obtained by using central differences embedded in a nine levels Richardson extrapolation procedure. Program summary Program title: Gmat Catalogue identifier: AECZ_v1_0 Program summary URL: http://***/stimmaries/AECZ_*** Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://***/licencel/*** No. of lines in distributed program, including test data, etc.: 17 023 No. of bytes in distributed program, including test data, etc.: 274 714 Distribution format: *** programming language: Standard C++ Computer: All running Linux/Windows Operating system: Linux, Windows Classification: 16.2 Nature of problem: Computation of the rovibrational G matrix in molecules of any size. This allows the building of arbitrary rovibrational Hamiltonians. It must be possible to obtain the input data front the output files of standard electronic structure
This paper describes a laboratory equipped for the teaching of advanced courses in computer engineering, computer science, information systems;and software engineering. Other related work areas include computer vision...
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This paper describes a laboratory equipped for the teaching of advanced courses in computer engineering, computer science, information systems;and software engineering. Other related work areas include computer vision, real-time systems, programming languages, and computer architectures. The laboratory has been built around a digital model railroad platform controlled by a client-server system using an object-oriented language. The characteristics of this laboratory are suitable for implementing Web activities for educational purposes. The paper also includes. an overview of the system in which most of these topics have been considered and a summary of the relationship with the most relevant international curricula in computing.
In this contribution we describe an object-oriented software architecture for image segmentation, 3-D pose estimation as well as Bayesian object recognition: models are represented by densities, model generation corre...
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In this contribution we describe an object-oriented software architecture for image segmentation, 3-D pose estimation as well as Bayesian object recognition: models are represented by densities, model generation corresponds to parameter estimation tasks, and the identification applies the Bayesian decision rule. We show results of 3-D object recognition experiments based on the observation of 2-D points or lines. (C) 1997 Elsevier Science B.V.
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