A computational framework has been developed for step-by-step implementation of global spectral projection methods used for solving boundary-value problems and for subsequent analysis of solutions produced using the n...
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A computational framework has been developed for step-by-step implementation of global spectral projection methods used for solving boundary-value problems and for subsequent analysis of solutions produced using the numerical techniques of this framework. A set of MATLAB-based functions corresponding to each step in a Galerkin discretization procedure has been developed with emphasis on simplifying the implementation of discretization methods for nonlinear, distributed-parameter system models in up to three-dimensional physical domains. A key feature of this computational approach is that a set of object classes was developed to facilitate implementation of the weighted residual methods (MWR) in an effort to make the connection between the solution procedures and modeling equations as clear as possible. The utility of the computational procedures is demonstrated through applications to two-dimensional reaction-diffusion and fluid flow problems, and a three-dimensional heat transfer model relevant to semiconductor manufacturing. (C) 2002 Elsevier Science Ltd. All rights reserved.
This paper presents a new modelling architecture and a formal modelling approach based on concepts derived from object-oriented programming. It also presents the conclusions of a comparative study of the methods used ...
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This paper presents a new modelling architecture and a formal modelling approach based on concepts derived from object-oriented programming. It also presents the conclusions of a comparative study of the methods used for numerical and formal solutions. The architecture and the approach that are described here have been applied to a complex real system: modelling the road behaviour of vehicles - articulated or not. Copyright (C) 1997 Elsevier Science Ltd.
Three object-oriented implementations of a prototype solver of the advection equation are introduced. The programs are based on Blitz++ (C++), NumPy (Python) and Fortran's built-in array containers. The solvers co...
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Three object-oriented implementations of a prototype solver of the advection equation are introduced. The programs are based on Blitz++ (C++), NumPy (Python) and Fortran's built-in array containers. The solvers constitute mentations of the Multidimensional Positive-Definite Advective Transport Algorithm (MPDATA). The introduced codes serve examples for how the application of object-oriented programming (OOP) techniques and new language constructs from C++ and Fortran 2008 allow to reproduce the mathematical notation used in the literature within the program code. A on the tradeoffs of the programming language choice is presented. The main angles of comparison are code brevity and clarity (and hence maintainability and auditability) as well as performance. All performance tests are carried out using free open-source compilers. In the case of Python, a significant performance gain is observed when switching from the standard terpreter (CPython) to the PyPy implementation of Python. Entire source code of all three implementations is embedded in text and is licensed under the terms of the GNU GPL license.
Metaphor is a multi-stage programming language extension to an imperative, object-oriented language in the style of C# or Java. This paper discusses some issues we faced when applying multi-stage language design conce...
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Metaphor is a multi-stage programming language extension to an imperative, object-oriented language in the style of C# or Java. This paper discusses some issues we faced when applying multi-stage language design concepts to an imperative base language and run-time environment. The issues range from dealing with pervasive references and open code to garbage collection and implementing cross-stage persistence. (c) 2006 Elsevier B.V. All rights reserved.
Although inspection is an effective. mechanism for detecting defects in procedural systems, object-oriented systems have different structural and execution models. This article describes the development and empirical ...
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Although inspection is an effective. mechanism for detecting defects in procedural systems, object-oriented systems have different structural and execution models. This article describes the development and empirical investigation of three techniques for reading object-oriented code during inspection.
Introduces flexible organizations (FORS), a design environment based on a network representation of a design. Components of the design network; Provision of icon based interface; Use of the system in the mechanical de...
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Introduces flexible organizations (FORS), a design environment based on a network representation of a design. Components of the design network; Provision of icon based interface; Use of the system in the mechanical design of car window regulators.
Inheritance provides object-oriented programming with much of its great reusability power. When inheritance is single, its specifications are simple and everybody roughly agrees on them. In contrast, multiple inherita...
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Inheritance provides object-oriented programming with much of its great reusability power. When inheritance is single, its specifications are simple and everybody roughly agrees on them. In contrast, multiple inheritance yields ambiguities that have prompted long-standing debates, and no two languages agree on its specifications. In this paper, we present a semantics of multiple inheritance based on metamodeling. A metamodel is proposed which distinguishes the "identity" of properties from their "values" or "implementations". It yields a clear separation between syntactic and semantic conflicts. The former can be solved in any language at the expense of a common syntactic construct, namely full name qualification. However, semantic conflicts require a programmer's decision, and the programming language must help the programmer to some extent. This paper surveys the approach based on linearizations, which has been studied in depth, and proposes some extensions. As it turns out that only static typing takes full advantage of the metamodel, the interaction between multiple inheritance and static typing is also considered, especially in the context of virtual types. The solutions proposed by the various languages with multiple inheritance are compared with the metamodel results. Throughout the paper, difficulties encountered under the open-world assumption are stressed. (C) 2010 Elsevier B.V. All rights reserved.
Different from object detection in natural images, aerial-view object detection faces special challenges with large changes in object orientation and wide multi-scale distribution. Many methods based on oriented Bound...
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Different from object detection in natural images, aerial-view object detection faces special challenges with large changes in object orientation and wide multi-scale distribution. Many methods based on oriented Bounding Boxes (OBB) can reach accurate results, yet may face the problem of parameter mutation and axis prediction deviation. To address these problems, a two-stage detection framework is proposed for arbitrary-oriented traffic participant detection and axis prediction, named Axis Prediction Network. First, a Deformable Convolution Fusion Module (DCF-Module) is proposed to enhance the ability of FPN to extract multi-scale semantic features, for dealing with the multi-scale change of objects. Then, the axis heat-map prediction head network is proposed to fit the long axis of orientedobjects labeled with Gaussian model, which uses pixel-by-pixel prediction heatmap to calculate the long axis of the object, avoiding the angle mutation of an OBB. Last, the long and short side prediction head network is proposed to predict the shape of an orientedobject, avoiding the mutation of the width and height of an OBB. The experiments are conducted on the new built Crossroad dataset and the public DOTA dataset. Experiment results show that the proposed method achieve good performance in arbitrary-oriented traffic participant detection and axis prediction in aerial view.
Ever since its introduction from Sun Microsystems four years ago, Java has been widely accepted in the computing and Internet industry. However, the runtime performance is still not good enough for Java to become a ge...
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Ever since its introduction from Sun Microsystems four years ago, Java has been widely accepted in the computing and Internet industry. However, the runtime performance is still not good enough for Java to become a general-purpose programming language. This article shows how to implement a Java microprocessor core in silicon to speed up the execution of Java. For a reconfigurable and flexible design, the field programmable gate array is chosen as a target technology for the Java microprocessor. By applying a top-down hardware design methodology to the FPGA design process, it becomes easier and more flexible to implement Java in a FPGA. The DFT technique is added for better testability.
An object-oriented message-passing class library in C++, called PPI++, for portable parallel programming has been developed. PPI++ (parallel portability interface in C++) is designed to serve as a stable (unchanging) ...
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An object-oriented message-passing class library in C++, called PPI++, for portable parallel programming has been developed. PPI++ (parallel portability interface in C++) is designed to serve as a stable (unchanging) interface between the client parallel code and the rapidly evolving distributed computing environments. By taking advantage of encapsulation, inheritance, and polymorphism supported by C++, PPI++ provides a clean and consistent programming interface, which helps improve the clarity and expressiveness of client parallel codes and hides implementation details and complexity from the user to ease parallel programming tasks. In addition, the use of strong type-checking in C++ allows the detection of potential misuses of the library at compile time, and thus promotes code reliability. This paper describes the object-oriented design and implementation of PPI++. Evaluation of PPI++ on important performance issues, such as portability, ease-of-use, extensibility, and efficiency, is also discussed.
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