摩托车智能设计系统的研究与开发

人工智能技术应用到摩托车设计中.根据摩托车设计知识的特点和分类,为了保证技术经验、专业知识不流失,应用面向对象的方法实现了实例知识的表示并构建了层次实例库,采用CLIPS语言实现规则知识的表示并创建了规则库,建立了实例推理和规则推理的集成推理机制.运用面向对象语言对推理结果(即设计对象)进行封装,封装的设计对象通过在方法中调用三维设计平台的二次开发函数实现参数化建模.根据上述方法开发的摩托车智能设计系统,可帮助开发人员快速地进行产品的创新设计与发展.     

面向对象基本概念与语言

面向对象技术已经成为计算机技术的不可分割部分。采用这个技术,在软、硬件开发和人工智能研究中都显现出巨大的优越性。但同时各种流派的面向对象设计的出现使人眼花潦乱。本文试图讨论面向对象程序设计的基本概念并介绍面向对象程序设计语言或系统的发展概况。对象、类、消息的程序设计模式其基本点在于对象的封装和继承性。封装使对象外界面和对象实现分离。要继承就得将对象管理起来并建立类体系。以及由此带来晚聚束和实体的多态性构成面向对象基本特征。文中论述这些特征有利于当前软件技术所追求的模块性、数据隐藏、数据抽象,可修改,易维护,并适宜于早期原型开发等目标。文中从模仿 Smalltalk、采用面向对象思想、可作面向对象设计三个方面简述了20余种基于对象的语言。     

面向对象的思想在虚拟仪器开发中的应用

按照模块化设计原则,将面向对象的思想应用于虚拟仪器的开发。通过将测试对象或者其操作抽象为相应类的实例,进而完成对表征这些客观对象的属性和操作的封装设计。应用这种思想,完成基于数据采集卡的硬件平台在Windows环境下利用Visual C＋＋6．0进行钻井液参数虚拟测试系统的开发,其中包括采集模块、被测对象、测试数据以及各种辅助模块的封装设计。工程实践证明,面向对象的思想能简化设计过程,开放仪器构架,便于系统的分析和移植。     

用C语言实现类封装的研究

多年以来,C语言在嵌入式软件开发中被广泛使用,但由于开发人员和应用场景等原因,面向对象、设计模式等优秀的软件开发方法始终没有很好地运用起来。时至今日,物联网等应用的兴起,给嵌入式软件开发带来新的挑战,而传统的面向过程开发已经难以支撑这些复杂的应用。因此,有必要在嵌入式软件开发中引入面向对象、设计模式等优秀的软件开发方法。面向对象是现代软件方法的根基,面向对象体现在类上,而封装为类的第一大特性。文章以类的封装特性为切入点,结合C语言的特性,讨论了C语言实现类封装的方法,并给出了实例。     

铁路信号与列车控制系统的面向对象仿真

该文叙述了面向对象技术（OOT）应用于铁路信号与列控系统建模的方法 ，利用面向对象分析（OOA）和面向对象设计（OOD），把信号系统组成实体的属性和操作封装成对象存贮在软件库中，并可利用这些对象评估铁路信号与列控系统。由于OOT的高可复用性、可扩展性和高开发效率，使得仿真系统的开发时间和费用大大节省。     

对象演算Ⅰ

对象演算是一个面向对象的逻辑演算系统,它建立在描述具有内部状态的动态演变实体的Trace演算之上.对象比一般意义下的动态实体具有更多和更好的特性,特别是封装性.为此,文章引入有效动作的概念,通过对象的有效动作来刻画对象的封装性,即只有对象的有效动作才能访问或修改对象的属性值,从而对Trace演算的语义模型加以限制,得到对象语义解释模型.作为逻辑系统,文章还讨论了对象演算的公理化,它是Trace演算公理系统的扩充.作为应用,文章结合实例给出了对象语义的描述及特性推理.     

OO技术在多层分布式系统中的应用

在多层分布式系统中,利用OO（Object Oriented面向对象）分析和OO设计才能开发出可以重复使用的企业对象,本文结合实例,在对象,继承,封装等概念的基础上,阐述了OO技术在分布式系统的分析、设计以及实现中的应用。     

基于实例的产品设计知识获取方法及实现

现代产品设计是面向市场、功能驱动以及基于新知识的设计，而知识获取是关键步骤。采用设计实例的形式对已有设计进行封装和组织，通过产品设计实例面向对象表达模型，将设计需求（包括性能需求、环境约束和成本约束）、设计任务、设计过程和设计方案封装在一个设计实例中，体现了功能驱动、面向市场的现代设计特征。在此基础上，利用Sybase公司的PowerDesigner8.0建模工具，进一步提出产品设计实例的获取模型，并对实例获取的关键技术进行了讨论。以滑动轴承设计为工程应用背景，选择应用于涡轮机的四油叶径向滑动轴承为设计实例，详细描述了集成于SolidWorks2000的滑动轴承设计实例获取模块的应用过程，验证了上述模型的正确性和可行性。通过对设计实例进行表达、获取和存储，为后续的基于实例推理的产品设计方法打下基础，同时以对外提供功能的形式对并行设计环境下的功能检索提供支持，推动现代产品概念设计自动化进程。     

专家系统中的面向对象技术

面向对象程序的核心特征是封装、继承、多态、层次。面向对象的程序设计是一种结构化技术，它基于类型层次，匿名对象通过为它设计的普通协议进行相互通信。在专家系统中使用面向对象的程序设计方法有很多优点。本文介绍在推理机与知识表示的实现方案中面向对象方法的应用。     

面向对象数据库系统中的DS-粗糙集及其应用

在面向对象数据库中,将属性和方法封装在一起形成类,类的实例构成对象。对象在方法的作用下,其属性值不断地发生变化,使得对象迁入或迁出集合,则研究的对象集合成为双向DS-集合。分析类与对象中的S-粗集特征,定义了基于动态特征的面向对象DS-粗集。DS-粗集具有类的封装性和隐蔽性特征,DS-粗集是S-粗集和粗集的一般形式,是S-粗集和粗集的进一步推广。最后通过一个简单实例说明了DS-粗集在面向对象数据库系统中的应用基础。     

以网络为中心的协同特征造型

在网络化同步协同设计环境中,如何实现CAD系统之间的实时数据交换和模型同步,成为协同几何造型的关键问题。文中提出了一种新的复制式协同特征造型方法,该方法将现有的特征造型技术与分布计算、网络通信技术相结合,通过简单的造型消息交换来实现增量式协同造型,可以较好地满足几何模型实时同步的需要,而且也部分地解决了异构CAD软件之间的数据交换问题;并详细地介绍了协同造型通信协议、对象引用机制、以及分布式协同造型系统。     

Multi-volume CAD modeling for heterogeneous object design and fabrication

The current computer-aided technologies in disign and product development,the evolution of CAD modeling,and a framework of multi-volume CAD modeling system for heterogeneous object design and fabrication are presented in this paper.The multi-volume CAD modeling system is presented based on nonmanifold topological elements.Material identifications are defined as design attributes introduced along with geometric and topological information at the design stage.Extended Euler operation and reasoning Boolean operations for merging and extraction are executed according to the associated material identifications in the developed multi-volume modeling system for heterogeneous object.An application example and a pseudo-processing algorithm for prototyping of heterogeneous structure through solid free-form fabrication are also described.     

Perspectives on hierarchical modeling in mechatronic design

Hierarchical modeling helps to describe product models and data from different viewpoints that, representing the different disciplines involved in the design process of mechatronic systems. This paper gives an overview of hierarchical modeling techniques. This includes the investigation of systems, which requires handling different issues that address very specific views of the system (system aspects) and come from various disciplines. Also the model granularity which describes the extent to which an object or model is broken down into smaller elements it an important aspect. The different phases of the product life cycle require models with different objectives and levels of detail. Some models are needed mainly in specific phases of the product life cycle, which are discussed in detail in the paper. Especially in the conceptual design phase some design-characteristic aspects such as hierarchy of parameters, modularity of the design should be analyzed, because in this phase the largest part of the later resulting product costs is predetermined or even fixed. As a consequence, the scope for design is limited to merely small changes in the subsequent design phases. Therefore the interaction between the design phases and the related models plays an important role the development process of mechatronic systems.     

An object-oriented database management system for computer-aided design of tall buildings

An effective database and database management system is the key to the success of an integrated approach to software engineering applications in general, and Computer-Aided Design (CAD) for structural applications in particular. Due to the inherent nature of CAD data such as dynamic modeling, a wide range of data types, large data volume, etc., the traditional database models, such as hierarchical, network and relational models, are unable to handle the aforementioned applications satisfactorily. An object-oriented data modeling is known to be the most effective approach. However, many of the commercial object-oriented databases are designed for information management, and they are inadequate for CAD application due to the different features of the object-hierarchy and varying data management objectives during the design cycles. This paper presents a hierarchical index-based object-oriented database management model for CAD applications. To deal with the object hierarchy encountered in CAD for the design of tall buildings, the proposed database consists of several salient features: a hierarchical object model, its related storage structure, a data dictionary, a class factory and an index system. The proposed database management model has been implemented into an integrated CAD system for design application of tall buildings.     

面向并行设计的虚拟原型技术研究

虚拟原型技术是在虚拟的逼真环境下,对产品设计信息进行协同仿真验证的有效手段,它可有效支持并行设计,缩短产品开发周期,在分析了虚拟原型与并行的关系后,提出了基于域对象的虚拟原型建模与仿真方法,并阐述了支持虚拟原型的集成框架的关键技术。     

Performance evaluation of collaboration in the design process: Using interoperability measurement

A design process, whether for a product or for a service, is composed of a large number of activities connected by data and information exchanges. The quality of these exchanges, called in this paper collaboration, requires the ability to exchange useful, understandable and unambiguous data and information to the different designers involved. In this paper, a global framework is first set for process/product performance management. Then, the research question focuses on the definition and evaluation of the performance of collaborations, and by extension, of the design process in its entirety. This performance evaluation requires the definition of several key elements such as object to evaluate, the performance criteria, indicators and action variables. In order to define the object of evaluation, this paper relies on a literature study on collaboration resulting in an ECORE meta-model of collaborative processes. The collaboration performance measurement is for its part based on the concept of interoperability. This measure estimates the technical and conceptual interoperability of the different pairwise collaborations. The paper is concluded by proposing a tooled methodology for collaborations’ performance evaluation including two main phases: process modeling and interoperability measurement. Tooling is provided through the Eclipse Modeling Framework (EMF) using its (meta-) model edition, constraint validation and model comparison features. The applicability of the methodology is also illustrated using a case study in design.     

A PDES/STEP-based model and system for concurrent integrated design and assembly planning

Product data exchange and interfacing between different CAD/CAM systems are of great importance to the development of concurrent integrated design environments and computer integrated manufacturing systems. This paper presents a STEP-based method and system for concurrent integrated design and assembly planning. An integrated object model for mechanical systems and assemblies is first defined by a hierarchy of structure, geometry and feature. The structure is represented as a component-connector or joint multi-level graph with both hierarchical functional and assembly relations. These hierarchical relation models are then used for uniformly describing their causal relations both for assembly level and feature based single part level. The generic product assembly model is organized according to STEP, using mostly the entities of integrated resources and partly self-defined entities, which are necessary for design and assembly planning. Based on the generic product assembly model, STEP-based strategies and agent concepts are used for agent-based concurrent integration of design and assembly planning. A prototype system, consisting of a CAD system, a product modeling system, an assembly planning system, and an assembly evaluation system is developed, in which product data can be exchanged between these subsystems. Details about the implementation of the system are addressed. The integrated design and assembly planning system can support the introduction of a new product. The results of assembly planning are feedback to the stage of assembly design to improve on the design. A case study is carried out for assembly-oriented design of a gearbox, to illustrate the proposed approach and to validate the developed system.     

A procedure for building product models

The application of product modeling in manufacturing companies raises the important question of how to model product knowledge in a comprehensible and efficient way. An important challenge is to qualify engineers to model and specify IT-systems (product models) to support their specification activities. A basic assumption is that engineers have to take the responsibility for building product models to be used in their domain. To do that they must be able to carry out the modeling task on their own without any need for support from computer science experts. This paper presents a set of simple, easily adaptable concepts and methods for modeling product knowledge. The concepts and methods are based on well-defined concepts and methods from data modeling (object oriented analysis) and domain modeling (product modeling). The concepts are general and can be used for modeling all types of specifications in the different phases in the product life cycle. The modeling techniques presented have been tested in different companies and have proved to work.     

面向产品设计改进的在线评论挖掘

以竞争市场环境中的产品在线评论数据为研究对象,基于支持产品设计改进的视角,采用数据挖掘的方法与工具,开展面向产品设计改进的在线评论大数据分析研究。重点开展在线评论数据挖掘过程模型中的有用性建模和特征评价值情感分析。以某智能手机产品的在线评论数据为对象进行了实验,得到该产品各个属性的评价值,与更新换代后的产品属性进行比较,验证了此方法的有效性。