集成虚拟现实环境在工程设计分析中的应用 *

虚拟现实技术在工程设计与分析上有很大的应用潜力。可是 ,虚拟环境的创建时间长、成本高,极大地限制了虚拟现实技术在工程上的应用。为此 ,提出了虚拟现实脚本生成器的概念,将虚拟现实技术与过程的设计、分析集成化,创造性地提出了一种自上而下的设计方法———VR-IEDA,以便高效、快速地创建虚拟原型,提高计算机虚拟复杂系统工程的性价比。在 VR-IEDA中复杂系统的结构和行为被计算机捕捉并自动生成可执行的 VR仿真代码 ,从而减少了创建虚拟环境的时间,便利了基于仿真的过程分析和设计。最后 ,以武器系统的维修过程为     

Model-driven engineering of process control software – beyond device-centric abstractions

This paper presents a new, two-level, model-driven engineering approach to industrial process control software. The first level (infrastructure engineering) is concerned with the following: the definition of the development process and guidelines, the definition of a domain-specific modeling language, the specification of the model transformations, and the development of a tool suite. This tool suite enables modeling of the process control software and the automatic code generation for programmable logic controllers. In the second level (application engineering), the process control software is engineered using the results of the infrastructure level. The approach is demonstrated on excerpts from an industrial project.     

NCSWT: An integrated modeling and simulation tool for networked control systems

Networked Control Systems (NCS) are becoming increasingly ubiquitous in a growing number of applications, such as groups of unmanned aerial vehicles and industrial control systems. The evaluation of NCS properties such as stability and performance is very important given that these systems are typically deployed in critical settings. This paper presents the Networked Control Systems Wind Tunnel (NCSWT), an integrated modeling and simulation tool for the evaluation of Networked Control Systems (NCS). NCSWT integrates Matlab/Simulink and ns-2 for modeling and simulation of NCS using the High Level Architecture (HLA) standard. The tool is composed of two parts, the design-time models and the run-time components. The design-time models use Model Integrated Computing (MIC) to define HLA-based model constructs such as federates representing the simulators and interactions representing the communication between the simulators. MIC techniques facilitate the modeling and design of complex systems by using abstractions defined in domain-specific modeling languages (DSMLs) to describe the systems. The design-time models represent the control system dynamics and networking system behaviors in order to facilitate the run-time simulation of a NCS. The run-time components represent the main software components and interfaces for the actual realization of a NCS simulation using the HLA framework. Our implementation of the NCSWT based on HLA guarantees accurate time synchronization and data communication. Two case studies are presented to demonstrate the capabilities of the tool as well as evaluate the impact of network effects on NCS.     

An integrated manufacturing system for rapid tooling based on rapid prototyping

To reduce the time and cost of moulds fabrication, a novel integrated developing and manufacturing system of rapid tooling (RT) based on rapid prototyping (RP) is proposed. The architecture of system which consists of four building blocks: digital prototype, virtual prototype (VP), physical prototype and RT system, is presented. A digital prototype can be established by 3D CAD software packages or reveres engineering technique. A VP is employed to guide in optimization of the mould design and manufacturing process planning. A physical prototype, which is built using RP technology, generally serves as a pattern for producing RT. By integrating these building blocks closely, the system can aid effectively in mould design, analysis, prototyping, simulating, and manufacturing process development. Three typical cases are discussed in detail to illustrate the application of the system. It has been shown from a number of case studies that the system has a high potential to reduce further the cycle and cost of die development while minimizing error introduction. As a result, the integrated system provides a feasible and useful tool for companies to speed up their product development.     

关于统一建模语言——UML

ＵＭＬ是面向对象开发中一种通用的、图形化的模型语言,是近代软件工程环境中对象分析和设计的重要工具。ＵＭＬ严格地定义了对象无模型的语义,提供了描述对象结构和行为的表示法。本文介绍了ＵＭＬ产生的技术背景、无模型的主要思想、表示法,以及应用系统建模的一般过程和对ＯＯ世界的意义。     

An Annotation Engine for Supporting Video Database Population

Segmentation, video data modeling, and annotation are indispensable operations necessary for creating and populating a video database. To support such video databases, annotation data can be collected as metadata for the database and subsequently used for indexing and query evaluation. In this paper we describe the design and development of a video annotation engine, called Vane, intended to solve this problem as a domain-independent video annotation application.Using the Vane tool, the annotation of raw video data is achieved through metadata collection. This process, which is performed semi-automatically, produces tailored SGML documents whose purpose is to describe information about the video content. These documents constitute the metadatabase component of the video database. The video data model which has been developed for the metadata, is as open as possible for multiple domain-specific applications. The tool is currently in use to annotate a video archive comprised of educational and news video content.     

语义驱动的集成化产品建模

针对复杂产品研发过程中多领域协同对产品知识共享和重用的需求,提出一种语义驱动的集成化产品建模方法.结合多本体技术,给出了集成化产品建模框架,该框架由概念层和模型层构成,概念层包括高层核心产品本体和领域本体,模型层由主模型和领域模型等一族模型构成;同时还给出了集成化产品模型的形式化语义描述,在构建高层核心产品本体的基础上建立主模型;基于多领域本体,进行由概念层语义驱动的领域模型快速重构,在语义理解基础上实现跨领域的产品知识重用.     

A semi-formal description of migrating domain-specific models with evolving domains

One of the main advantages of defining a domain-specific modeling language (DSML) is the flexibility to adjust the language definition to changing requirements or in response to a deeper understanding of the domain. With the industrial applications of domain-specific modeling environments, models are valuable investments. If the modeling language evolves, these models must be seamlessly migrated to the evolved DSML. Although the changes stemming from the language evolution are not abrupt in nature, migrating existing models to a new language is still a challenging task. Our solution is the Model Change Language (MCL) tool set, which defines a DSML to describe the migration rules and then performs the model migration automatically. In this paper, we describe the precise semantics of MCL and its execution, along with the confluence of the migration.     

A structured methodology for implementing engineering data management

One of the most significant positive effects on product and process development in recent years has been the application of data management techniques. Engineering data management or product data management is the most promising one. The implementation of engineering data management is heavily dependent on the engineering process and involves the technologies of management, engineering, and information. However, as there is no commonly acceptable approach and methodologies for implementing engineering data management, it’s implementation becomes a bottleneck.This paper presents a structured methodology for the implementation of engineering data management. The approach consists of a series of steps, from business and engineering process analysis, modeling and reengineering, through system design and modeling, to system realization.This research will facilitate engineering process improvement and the planning, design and implementation of engineering data management. Consequently, it will help increase product development capability and quality, reduce development cycle time and cost, and hence increase product marketability.     

BIM技术在水闸设计中的应用

为促进水利建设行业的数字化技术发展,提高设计质量和效率,加快水利工程建设的数字化转型,以崇明岛堡镇港等 4 座水闸外移工程为例,基于 BIM 技术进行参数化设计研究与应用,通过协同设计、参数化模板库、精细化建模、有限元分析等技术实现 BIM 技术在数字设计中的全要素和全过程的应用,推动水闸建设的数字一体化设计的发展,提升设计品质和效率。另外,通过构件数据编码与数字化模型管理平台相连通,实现模型构件、信息的数字化管理及传递,为全生命周期内的智慧工程应用提供坚实的数据基础,有效推进设计过程的精细化管理,为后续其他水利工程项目的 BIM 应用提供良好的理论支持。     

STATEMATE环境下数据软件接口的开发

嵌入式系统在现代汽车电控装置上的广泛应用使得软件工程在汽车产品开发过程中的地位越来越重要。要提高车用电控软件的开发效率,只有通过有效地使用计算机辅助软件工程的有关工具(CASE-Tools),如建模、仿真和软件测试工具等才可能实现。但由于技术和商业上的原因,构成开发链的各种工具之间往往缺少有效的衔接,形成了开发过程中的瓶颈。该文介绍了在集成开发环境STATEMATE下开发的一个数据接口,可以实现仿真环境与软件测试环境的连接,从而提高嵌入式系统软件的开发效率。     

Integration of DFDs into a UML-based Model-driven Engineering Approach

The main aim of this article is to discuss how the functional and the object-oriented views can be inter-played to represent the various modeling perspectives of embedded systems. We discuss whether the object-oriented modeling paradigm, the predominant one to develop software at the present time, is also adequate for modeling embedded software and how it can be used with the functional paradigm. More specifically, we present how the main modeling tool of the traditional structured methods, data flow diagrams, can be integrated in an object-oriented development strategy based on the unified modeling language. The rationale behind the approach is that both views are important for modeling purposes in embedded systems environments, and thus a combined and integrated model is not only useful, but also fundamental for developing complex systems. The approach was integrated in a model-driven engineering process, where tool support for the models used was provided. In addition, model transformations have been specified and implemented to automate the process. We exemplify the approach with an IPv6 router case study.This article is an extension of two papers [1,2] published in the proceedings of IEEE International Conference and Workshop on the Engineering of Computer Based Systems (ECBS 2004).     

An object-oriented blackboard based approach for automated finite element modeling and analysis of multichip modules

This paper addresses the application of the blackboard system architecture and object-oriented data abstraction techniques to the domain of finite element modeling and analysis. Specifically, a hierarchical object-oriented database was used to represent the physical system at different levels of abstraction including the user-defined physical system level, a computer-generated, simplified physical model level, and the finite element model level. Object link relationships within a given abstraction level and across different abstraction levels resulted in seamless bidirectional information exchange. The blackboard system architecture employed provided a framework for distributed cooperative problem solving, for the application of simplifying domain-specific modeling assumptions, and for integrating the various software modules that are involved in the entire finite element modeling and analysis process. These methodologies were implemented in a prototype computational tool calledIMCMA theIntelligentMultichipModuleAnalyzer. An example illustrates howIMCMA automates finite element thermal analysis of small integrated circuit features in multichip modules through a two-step finite element submodeling process.     

AN UNSUPERVISED INCREMENTAL LEARNING ALGORITHM FOR DOMAIN-SPECIFIC LANGUAGE DEVELOPMENT

While grammar inference (or grammar induction) has found extensive application in the areas of robotics, computational biology, and speech recognition, its application to problems in programming language and software engineering domains has been limited. We have found a new application area for grammar inference which intends to make domain-specific language development easier for domain experts not well versed in programming language design, and finds a second application in construction of renovation tools for legacy software systems. As a continuation of our previous efforts to infer context-free grammars (CFGs) for domain-specific languages which previously involved a genetic-programming based CFG inference system, we discuss extensions to the inference capabilities of GenInc, an incremental learning algorithm for inferring CFGs. We show that these extensions enable GenInc to infer more comprehensive grammars, discuss the results of applying GenInc to various domain-specific languages and evaluate the results using a comprehensive suite of grammar metrics.     

Building a database design laboratory on the Internet

Commercial tools for software engineering include many development environments to support the design process. These integrated tools are usually distributed through traditional retail channels, with vendors increasingly giving customers the option of downloading products from the Web. The tools are installed on user client machines and are usually duplicated for actual tool use at customer sites. Users are responsible for installation, maintenance and upgrade procedures. We developed Web Lab as part of a project sponsored by the European Commission to advance rule-based, object-oriented technologies for developing database applications. The Web Lab was designed to help disseminate the research results. It enables remote use of a design environment for database applications, including a repository for application development that provides a protected workspace. However, as software becomes more and more a commodity, we expect vendors to begin selling software use rather than tools, an option that is particularly attractive in the context of thin clients running on network computers. Web Lab demonstrates the feasibility of this idea for commercial software distribution. We describe the Web Lab project, its implementation, and plans for further development     

Enabling control software generation by using mechatronics modeling primitives

Mechatronic systems are characterized by the synergetic integration of mechanic, electronic, software and control design aspects. The development of control software requires data and information from all design domains in order to create the required integrated functionality. This paper proposes a method that combines function modeling and multi-domain modeling primitives to generate control software automatically. An architecture model, based on the Function-Behavior-State modeling paradigm, provides the decomposition and flow of both functionality and implementation, which serves as input to a knowledge-based engineering application. The control software is subsequently extracted from a virtual product model composed of instantiated modeling primitives. A case study of a mobile robot shows how for a specific application the modeling are defined and how a high-level function model for an environment mapping mission is translated into directly implementable software code. This approach could be extended to real-life mechatronic products, and will improve consistency and reduce development time and cost.     

Knowledge-based approach and system for assembly-oriented design,Part II: the system implementation

Assembly is one of the most important stages for product development. Assembly-oriented design (AOD) is a new approach to designing assemblies, which uses a number of design and analysis tools to help the designer plan out and analyze candidate assembly schemes prior to having detailed knowledge of the geometry of the parts. Using this approach, many assembly schemes can be inexpensively evaluated for their ability to deliver the important characteristics of the final product. This research proposes a knowledge-based approach and develops an expert design system to support top-down design for assembled products. The presentation of research report is divided into two parts: the knowledge-based approach (Part I) and the knowledge-based expert design system (Part II). This paper is the second part of the report (Part II). It will focus on the development of knowledge-based expert design system for assembly oriented design. The knowledge-based assembly oriented design system, i.e., the assembly oriented design expert system (AODES) is constructed to integrate assembly modeling and design, assembly planning, assemblability analysis and evaluation within a concurrent engineering environment. This intelligent system is implemented by integrating object-oriented representation, constraint-based modeling, rule-based reasoning, truth maintenance, and interfacing to database management system and CAD module, in which fuzzy logic based knowledge representation and inference technique are also applied to deal with uncertain data and knowledge in the design process. The developed system differs from the existing systems adopting part-first bottom-up modeling technique, in which a comprehensive intelligent framework is used for assembly modeling and design in a top-down manner from the conceptual level to the detailed level. It is able to help obtain better design ideas, provide users with suggestions so as to create and improve a design, and therefore give users the possibility to assess and reduce the total production cost at an early stage during the design process. Through the use of the system, the concurrent engineering knowledge can be effectively incorporated into the assembly design process in an integrated manner. A case assembly design shows that the intelligent modeling and design system is feasible.     

On the modeling and generation of service-oriented tool chains

Tool chains have grown from ad-hoc solutions to complex software systems, which often have a service-oriented architecture. With service-oriented tool integration, development tools are made available as services, which can be orchestrated to form tool chains. Due to the increasing sophistication and size of tool chains, there is a need for a systematic development approach for service-oriented tool chains. We propose a domain-specific modeling language (DSML) that allows us to describe the tool chain on an appropriate level of abstraction. We present how this language supports three activities when developing service-oriented tool chains: communication, design and realization. A generative approach supports the realization of the tool chain using the service component architecture. We present experiences from an industrial case study, which applies the DSML to support the creation of a service-oriented tool chain. We evaluate the approach both qualitatively and quantitatively by comparing it with a traditional development approach.     

Development of a computer-aided concurrent net shape product and process development environment

This paper presents a systematic approach to developing a collaborative environment for computer-aided concurrent net shape product and process development. This approach includes the steps of (1) conventional development process analysis, (2) development process re-engineering, (3) computer-based system functional requirements analysis, (4) system framework design, and (5) system modeling, integration and implementation. This environment can support concurrent net shape product and process development by providing and integrating functions of product data management, process management and development advisory tools. The results of this research will facilitate the rationalization and automation of net shape product and process development and thus improve the efficiency and quality, and reduce the cost of net shape product development.

IDEF structural analysis methodology was employed to capture the characteristics of net shape product and process development process. The concept of concurrent engineering was used to re-engineer the development process. The technology of system engineering was used to design the computer-aided system framework. Object-oriented analysis, modeling and design methodology, knowledge engineering and data engineering techniques were employed for system modeling and implementation.     

A meta-process model for the planned development of integrated systems

Maturity of technologies from one side and customers' demands from the other side have led to the need to develop increasingly large and complex systems. The problem we face is to structure the development of these types of systems and the systems themselves in a useful way and to support the development process from its conceptual foundation to its tool aspect.We believe that we must take one step beyond the current software engineering methodology to be able to cope with this task. What we propose is a framework, a meta-process model, that allows one to develop in a flexible but integrated manner a distributed, open, and integrated system with a planned approach. Based on the premise that the main factor is to build a common culture of understanding and conceptual thinking in an application domain, we suggest an additional level of coordination and modeling above the various development projects. In analyzing this two-leveled process model, we identify the major processes and models involved. While we focus on the process model itself, we discuss also in some more depth the two major concepts of domain analysis and integration architecture design as they relate to our approach. A strategy for realizing the meta-process model based on the notion of Application Machines is described.