机械产品概念设计中的知识表示

研究了计算机辅助概念设计中的关键技术——知识表示．将行为域引入公理化设计作为功能域和载体域之间的转换桥梁，针对该域结构定义扩展“之”字映射，建立了不同层次功能、行为和载体之间的映射关系；构造了概念设计方案的知识表示模型——域结构模板；针对一类产品的知识表示模型——概念空间，给出了基于概念空间的概念设计方案生成过程．最后以工业平缝机为例对所述模型和方法加以说明。     

Function and process modeling for integrated product and manufacturing system platforms

Manufacturing companies face increasingly tougher individual customer requirements that force them to revise conceptual solutions for the redesigning of products. This situation limits the reuse of ready-made components and requires physical changes to the manufacturing system. In these settings, platforms must be prepared with greater flexibility to allow development over time. The corresponding platform models need to include conceptual considerations for products and manufacturing systems. The literature advocates functional modeling to capture these considerations but applies it separately to either the product domain or to the manufacturing domain. Further, its relationship to manufacturing processes is not expounded. Thus, functional modeling falls short of its potential to facilitate the integrated development of products and manufacturing systems.This paper puts forth an integrated platform model using functional modeling to capture the conceptual considerations for products and manufacturing systems together with the manufacturing processes. The model is tested for consistency and then illustrated by studying a real case example from the automotive industry modeled according to the approach suggested. The example shows that the model facilitates an understanding of the design of products and their manufacturing systems, including functions shared across domains and across lifecycle phases. Thus, the model is proposed for the conceptual phase of designing, aimed at reusing and redesigning components, machinery, manufacturing processes and design solutions.     

Development of the science base for the manufacturing field through the axiomatic approach

The field of design needs a science base or absolute principles and axioms that can properly guide human endeavor for better creation, i.e., better design that leads to more economical use of natural resources and that which serves those human aspirations more effectively without accompanying undesirable side effects. The purpose of this paper is to describe the axiomatic approach to design. The design axioms and their corollaries are given and their use is explained both qualitatively and quantitatively. The metrics for the axiomatic statements are defined and their meanings explained through graphical representations. To further the understanding of the significance of the axioms, many examples are given, including product and process designs.     

Generation and evaluation of product concepts by integrating extended axiomatic design,quality function deployment and design structure matrix

Existing product concept generation and evaluation methods are mainly based on designers' experience to determine design schemes in the process of product development, which is time-consuming and ineffective. This paper proposes an approach to generate and evaluate design concepts by integrating the extended axiomatic design, quality function deployment and design structure matrix. Different design domains are mapped for matrix operations to generate feasible concepts based on design criteria. A domain mapping matrix is built to determine technical measures, functional requirements and design parameters based on customer requirements. The proposed approach provides a structured method to quantify, validate and qualify design concepts. A case study of the design of a hand rehabilitation device demonstrates the effectiveness of the proposed method.     

Development of holonic manufacturing execution systems

Rapid changes of market demands and pressures of competition require manufacturers to maintain highly flexible manufacturing systems to cope with a complex manufacturing environment. To meet these requirements, this work adopts the concepts of holon and holarchy to design manufacturing systems. Holon and holarchy are derived from the studies of social organizations and living organisms and possess the properties of intelligence, autonomy, cooperation, reconfigurability, and extensibility. Moreover, advanced manufacturing systems also require the properties of security certification and failure recovery. Based on the requirements of these properties, a systematic approach is proposed to develop a holonic manufacturing execution system (HMES) for the semiconductor industry. This systematic approach starts with a system analysis by collecting domain requirements and analyzing domain knowledge. The HMES Holarchy is designed by the procedure of constructing an abstract object model based on domain knowledge, partitioning application domain into functional holons, identifying generic parts among functional holons, developing the Generic Holon, defining holarchy messages and the holarchy framework of HMES, and finally designing functional holons based on the Generic Holon. It is believed that this proposed systematic approach provides a novel and efficient way to design HMES.     

Formal foundations for object-oriented data modeling

Class dictionary graphs, axiomatic definitions of basic structures used by object-oriented designers and programmers during the software development process, are discussed. An axiomatic foundation for object-oriented data modeling and efficient algorithms for checking whether a given data model satisfies the axioms are presented. The data model is the foundation for a number of techniques for developing object-oriented systems, including adaptive software, schema abstraction from object examples, schema optimization, planning techniques for system development, and the Law of Demeter, among others     

多旋翼飞控推进子系统的Coq形式化验证

飞行器需要高可靠的飞行控制系统软件(飞控)来控制其运行.在传统开发模式下,先由人工将领域知识描述为自然语言形式的模型,再根据模型手动编写代码,然后使用软件测试技术来排除软件错误,这种模式由于人工易出错、自然语言存在二义性、测试技术的不完备性,导致难以构建出高可靠的飞控软件.基于形式验证技术的新型软件开发方法可从多方面提高飞控系统的可靠性.使用Coq定理证明器对全权提出的多旋翼飞控推进子系统进行了完整的形式验证,生成了一个可用的高可靠函数式软件库.主要工作有:首先将领域知识整理为具有层次结构以适合进行形式验证的文档,分离了基本函数和复合函数,并提出最简形式函数概念;再根据该文档进行形式化描述,定义常量、变量、基本函数、复合函数、最简形式函数和公理等;其次对各类导出函数的推导正确性建立为引理并予以证明;再次对多旋翼最长悬停时间等实际问题给出了求解算法;最后利用Coq程序抽取功能生成了OCaml语言的函数式软件库.后续将对飞控更多子系统进行基于形式验证的开发,并最终建立完整的经形式化验证的高可靠飞控系统.     

An algebraic description of system behaviours

The paper is an attempt of characterizing algebraically the sets of processes generated by systems. A characterization is given for discrete systems which are equivalent to the condition- event systems in the sense of Petri. The stress is put on the existing concurrency of processes. Main feature of the approach is that processes are regarded as primitives which need not to be defined. Only relationships between processes are described and this is done in terms of two partial operations of composing processes: sequentially and in parallel. Natural axioms are imposed on these operations such that the resulting structure of processes of a system can be represented as a partial algebra of labelled partially ordered sets of a sort with suitable compositions. In particular, from the axiomatic characterization of behaviour a process concept and other related concepts can be derived.     

A tutorial and review of object-oriented design of manufacturing software systems

Object-oriented design represents a relatively new method of software system design that provides a means for the development of robust software systems. This approach is what software developers need to deal with the dynamic nature of the manufacturing organization and the processes contained within. This paper presents a tutorial which focuses on the application of object-oriented design and programming to manufacturing software development. This essay begins with an examination of object-oriented software design (OOD) and how it compares with traditional algorithmic design. The discussion reviews the major elements of an object-oriented system and discusses how these elements support the development of complex software systems using examples from manufacturing as support. This is followed by a discussion of the steps to use as one approach to object-oriented design. The paper concludes with a review of object-oriented manufacturing systems reported in the literature.     

Fuzzy multi-attribute selection among transportation companies using axiomatic design and analytic hierarchy process

The basic concept in axiomatic design (AD) is the existence of design axioms. First of these axioms is the independence axiom and the second one is the information axiom. Information axiom proposes the selection of the best alternative that has minimum information. Analytic hierarchy process (AHP) is another multi-attribute method which is a decision-making method for selecting the best among a set of alternatives, given some criteria. The method has been extensively applied, especially in large-scale problems where many criteria must be considered and where the evaluation of alternatives is mostly subjective. Multi-attribute transportation company selection is a very important activity for effective supply chain. Selection of the best company under determined criteria (such as cost, time, damage/loss, flexibility and documentation ability) using both multi-attribute AD and AHP will be realized in this study. The fuzzy multi-attribute AD approach is also developed and it is compared by one of fuzzy AHP methods in the literature. The selection process has been accomplished by aiding a software that includes crisp AD and fuzzy AD.     

Using security robustness analysis for early-stage validation of functional security requirements

Security is nowadays an indispensable requirement in software systems. Traditional software engineering processes focus primarily on business requirements, leaving security as an afterthought to be addressed via generic “patched-on” defensive mechanisms. This approach is insufficient, and software systems need to have security functionality engineered within in a similar fashion as ordinary business functional requirements. Functional security requirements need to be elicited, analyzed, specified and validated at the early stages of the development life cycle. If the functional security requirements were not properly validated, then there is a risk of developing a system that is insecure, deeming it unusable. Acceptance testing is an effective technique to validate requirements. However, an ad hoc approach to develop acceptance tests will suffer the omission of important tests. This paper presents a systematic approach to develop executable acceptance tests that is specifically geared for model-based secure software engineering processes. The approach utilizes early-stage artifacts, namely misuse case and domain models, and robustness diagrams. The feasibility of the proposed approach is demonstrated by applying it to a real-world system. The results show that a comprehensive set of security acceptance tests can be developed based upon misuse case models for early-stage validation of functional security requirements.     

公理化设计框架下产品设计知识重用的关键技术

针对具有层次性、多属性特点的复杂产品设计过程,对公理化设计框架下的产品设计重用技术进行了研究。通过建立公理化设计框架将复杂产品设计过程进行分解,形成产品设计的需求域、功能域、结构域与工艺域的Z形映射关系,提出一种基于实例的综合考虑设计域间和域内设计信息的知识重用方法,采用基于相似度的知识重用检索算法,获得符合设计要求的最佳重用对象,并以实例进行了验证。     

An axiomatic theory of engineering design information

Recent research in design theory has sought to formalize the engineering design process without particular concern for the paradigm used to model design information. The authors propose that no correct formalization of the design process can be achieved without first formalizing the semantics of the information used in the process. To this end, the authors present a new formal theory of design information. The theory, called the hybrid model (HM), is an extended form of axiomatic set theory, and relies on it for consistency and logical rigor. The theory is stated as a collection of axioms, using a standard logic notation. Design entities are modeled by formal units calledobjects. Generalized functions and relations are used to formalize important ordering schemes and abstraction mechanisms relevant to design, including classification by structure and by function, aggregation, specialization, and generalization. The hybrid model is meant not only to aid in the study of the design process itself, but also to improve communications between designers, assist standardization of design specifications, and develop new, powerful software tools to aid the designer in his work.     

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.     

Set based robust design of mechanical systems using the quantifier constraint satisfaction algorithm

Embodiment design is an important phase of the design process where the initial design parameters and their feasible solution spaces with design configurations are decided for the design problem. This article presents a new approach of embodiment design space exploration of the product based on set based design with integration of robustness for the mechanical systems. The approach presented addresses the initial design phase of the mechanical systems design and provides a three step approach based on a formal expression syntax, transformation and evaluation engine and a computational algorithm for performing a domain search for sets of robust solutions for the product designs by taking into the account the variations and uncertainties related to the manufacturing process and material. The approach is based on the design domain exploration and reduction techniques. This is achieved by the utilization and integration of existential and universal quantifiers from the quantifier constraint satisfaction problem (QCSP) for the expression of the parameters and variables related to the product design and robustness. The quantifier notion has been used to develop the consistency check for the existence of a design solution and existence of a robust design solution. In order to compute the developed quantifier approach, an algorithm based on the transformation of the quantifier with interval arithmetic has also been developed. In order to demonstrate the capability of the developed approach, this article includes three examples of mechanical systems from earlier research works that apply the quantifier model and the resolution algorithm to successfully explore the design domain for robust solutions while taking into account different types of variations such as variations in mechanical/material properties, manufacturing variations or variations in geometric dimensions which may be of continuous or discrete type.     

对逻辑覆盖软件测试准则的公理化评估

由于形式规格说明采用一种精确、一致、容易被机器自动处理的符号系统来描述软件需求,因而形式规格说明为测试用例的自动生成和软件功能的验证提供了基础.在基于形式规格说明的测试过程中逻辑覆盖测试准则是一组常用的测试准则,如何选择和使用其中的每个测试准则是应用这组测试准则时面临的主要问题.因此分析和比较这组测试准则中每个测试准则的性质将为测试工程师选择测试准则提供指导和帮助.对测试充分性准则的公理化评估是一种比较测试准则的方式,这种方式将对理想的测试准则的直觉需求定义为一组公理,然后通过检查测试准则是否满足该组公理来分析和比较相应的测试准则.描述了一组理想的逻辑覆盖测试准则应该具有的性质和用来确定一个测试充分性准则是否完全的生成算法.这组性质被形式化地定义为一组公理.利用这种形式化的定义,用定理的形式精确地给出了这些性质之间的关系.最后通过这组公理系统来评估现有的逻辑覆盖测试准则.评估的结果为测试人员在实际过程中选择逻辑覆盖测试准则提供了指导.     

Computationally efficient ontology selection in software requirement planning

Understanding the needs of stakeholders and prioritizing requirements are the vital steps in the development of any software application. Enabling tools to support these steps have a critical role in the success of the corresponding software application. Based on such a critical role, this paper presents a computationally efficient ontology selection in software requirement planning. The key point guiding the underlying design is that, once gathered, requirements need to be processed by decomposition towards the generation of a specified systems design. A representational framework allows for the expression of high level abstract conceptions under a single schema, which may then be made explicit in terms of axiomatic relations and expressed in a suitable ontology. The initial experimental results indicate that our framework for filtered selection of a suitable ontology operates in a computationally efficient manner.     

How to achieve consistency for 3D city models

Consistency is a crucial prerequisite for a large number of relevant applications of 3D city models, which have become more and more important in GIS. Users need efficient and reliable consistency checking tools in order to be able to assess the suitability of spatial data for their applications. In this paper we provide the theoretical foundations for such tools by defining an axiomatic characterization of 3D city models. These axioms are effective and efficiently supported by recent spatial database management systems and methods of Computational Geometry or Computer Graphics. They are equivalent to the topological concept of the 3D city model presented in this paper, thereby guaranteeing the reliability of the method. Hence, each error is detected by the axioms, and each violation of the axioms is in fact an error. This property, which is proven formally, is not guaranteed by existing approaches. The efficiency of the method stems from its locality: in most cases, consistency checks can safely be restricted to single components, which are defined topologically. We show how a 3D city model can be decomposed into such components which are either topologically equivalent to a disk, a sphere, or a torus, enabling the modeling of the terrain, of buildings and other constructions, and of bridges and tunnels, which are handles from a mathematical point of view. This enables a modular design of the axioms by defining axioms for each topological component and for the aggregation of the components. Finally, a sound, consistent concept for aggregating features, i.e. semantical objects like buildings or rooms, to complex features is presented.     

Higher Order Software—A Methodology for Defining Software

The key to software reliability is to design, develop, and manage software with a formalized methodology which can be used by computer scientists and applications engineers to describe and communicate interfaces between systems. These interfaces include: software to software; software to other systems; software to management; as well as discipline to discipline within the complete software development process. The formal methodology of Higher Order Software (HOS), specifically aimed toward large-scale multiprogrammed/multiprocessor systems, is dedicated to systems reliability. With six axioms as the basis, a given system and all of its interfaces is defined as if it were one complete and consistent computable system. Some of the derived theorems provide for: reconfiguration of real-time multiprogrammed processes, communication between functions, and prevention of data and timing conflicts.     

层次结构MAS模型的设计与实现

Agent技术被越来越多地用于在不同领域开发软件系统,多Agent模型的研究已经成为热点。本文提出层次结构多Agent模型概念,结合一个实例,论述了层次结构MAS模型的基本思想和结构框架,研究了层次结构MAS模型的设计与实现过程。