ISSN:0883-9514    

DOI:10.1080/08839519408945437

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

I review research in the last decade in the framework called functional representation (FR). FR is a language for describing the function of a device, its structure, and the causal processes in the device that culminate in the achievement of the function. The causal transitions are annotated in specific ways that explain the role of the functions of the components and domain laws in the achievement of various states and, hence, the function of the device. I describe the uses of FR for simulation, diagnosis, and design, among other tasks.

ISSN:0883-9514    

DOI:10.1080/08839519408945438

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

There seems to be confusion in the literature to date regarding the concepts of intent, purpose, function, behavior, and structure in design. This paper is meant to provide a focus for discussion on the disambiguation of such concepts. The paper argues for the integration of concepts relating to both the human sociocultural environment and the physical environment in arriving at definitions meaningful to designers from different disciplines. Issues such as decomposition and specialization are addressed, and finally, a means of representation with the expressive power and flexibility required is presented.

ISSN:0883-9514    

DOI:10.1080/08839519408945439

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

We analyze Junctional models in the wide spectrum of model types. Our premise is that, in order to identify the merits of model types, their perceptions of reality are important. We classify modeling approaches into two categories, the kernel and the interpretative. The kernel approach, which assumes that the world can be modeled by a composition of predefined primitives, suffers from important drawbacks. The interpretative approach, to which the functional models belong, assumes that we know how things work. We investigate the characteristics of this approach from a diagnostic point of view and show that, although it provides a powerful tool for describing devices, it is hindered by serious disadvantages when used in isolation. We advertise the use of multiple models as a solution and provide an ontological semantic network as a framework for the integration of multiple model types.

ISSN:0883-9514    

DOI:10.1080/08839519408945440

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

In this paper we focus on the concept and representation of function in the context of the multi-modeling approach. The main contribution of the paper is to discuss the nature of functional knowledge and to disambiguate this type of knowledge from other types, such as teleology, behavior, and structure. Moreover, a general and theoretically sound framework for integration of these types of knowledge into a coherent system is proposed. Existing approaches to the definition and the representation of function are compared and their major limitations are highlighted. The concept of function and its representation in the multimodeling approach are illustrated. An example of functional representation concerning a household electric buzzer is discussed and the relations between functional knowledge and teleological, behavioral and structural knowledge are presented. The main contributions of our approach in the domain of diagnostic reasoning are summarized, and the paper concludes by mentioning current research work.

ISSN:0883-9514    

DOI:10.1080/08839519408945441

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The purpose of this paper is to describe a modeling methodology called multilevel flow modeling (MFM), which the author has developed for the representation of goals and functions of complex industrial plants. The idea of the methodology is to apply functional concepts to represent a plant at multiple interrelated levels of abstraction. MFM is currently used in supervisory control applications for aiding the operator in diagnosis and planning. It is also used in the conceptual analysis and synthesis of control systems. The paper provides an introduction to the basic concepts of MFM, details two modeling examples, and describes the object-oriented tool Abstractions used for the implementation of MFM models and for diagnosis and planning applications. Finally, the paper presents a review of the use of MFM in previous and ongoing international projects.

ISSN:0883-9514    

DOI:10.1080/08839519408945442

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

This report describes an ongoing effort to apply the functional modeling (FM) approach to the representation of and reasoning about engineered artifacts. The application domain is the external active thermal control system (EATCS) of space station Freedom. The intuitions behind FM are threefold. First, knowing the purposes of a device allows organization of the causal understanding of how a device works. Second, causality may be represented in modular chunks, which are indexed by the purposes of the device and its interrelated subsystems. Finally, the global behavior of a device in a given situation can be understood by composition of the relevant causal net fragments. These starting intuitions provide a framework for organizing calculations about a device and for performing a limited type of simulation with the organized ensemble. Parallel to the FM modeling effort for EATCS is the development of a methodology that generates diagnostic knowledge for a device directly from its FM representation. This knowledge compilation strategy takes the FM representation of the target device and compiles organized knowledge structures for troubleshooting. The knowledge structures are utilized in two ways for diagnosis: (1) efficient hypothesis generation and (2) hypothesis evaluation. The central result of the research reported here is that an FM representation of a device can be used to generate knowledge for diagnostic troubleshooting.

ISSN:0883-9514    

DOI:10.1080/08839519408945443

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

ISSN:0883-9514    

DOI:10.1080/08839519408945444

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor