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The need for a product model which can support the modelling requirements of a broad range of applications leads to the application of a feature-based model. An important requirement in feature-based design and manufacture is that a single feature representation should be capable of supporting a number of different applications. The capability of representing products composed of assemblies is seen to be necessary to serve the information needs of those applications. To achieve this aim it is an essential prerequisite to develop a formal structure for the representation of assembly information in a feature-based design system. This research addresses two basic questions related to the lack of a unified definition for features and the problem of representing assemblies in a feature-based representation. The intention is to extend the concept of designing with features by incorporating assembly information in addition to the geometrical and topological details of component parts. This allows models to be assembled using the assembly information within the feature definitions. Features in this research are defined as machined volumes which are represented in a hierarchical taxonomy. The taxonomy includes several types and profiles of features which cover a general range of machined parts. A hierarchical assembly structure is also defined in which features form basic entities in the assembly. Each feature includes information needed to establish assembly relationships among features in the form of mating relationships. An analysis of typical assemblies shows that assembly interfaces occur at the face level of the mating features and between features themselves. Three mating relationships between pairs of features have been defined (against, fits and align) and are represented in the form of expressions that can be used for evaluations. Various sub-types of these major mating relationships can be identified (e.g. tight fit, clearance fit, etc.) and represented through the use of qualifying attributes. Component Relation Graphs, Feature Relation Graphs and Face Mating Graphs have been developed to represent each level of interaction in an assembly, and assembly relationships are combined with knowledge on process planning into a Component Connectivity Graph. These graphs are used as the basis for deriving an integrated data structure which is used for defining classes for each level in the assembly hierarchy. The implementation of a prototype system has been facilitated by use of an object-oriented programming technique which provides a natural method of adding functionality to the geometric reasoning process of features and the complex relationships between the parts that make up the assembly. The feature-based model is embedded in an object-oriented solid modeller kernel, ACIS®. The research demonstrates the possibilities for a single feature representation to support multiple activities within a computer integrated manufacturing environment. Such a representation can form the basis of design improvement techniques and manufacturing planning as well as be a model to support the life cycle of the product.

Thesis (PhD)--University of South Australia, 1996

Thesis (Ph. D.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains xii, 264 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 157-167).

Thesis (Ph.D.)--West Virginia University, 2007. / Adviser: B. Gopalakrishnan. Includes bibliographical references.

Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [86]-90).

A revision of the author's thesis, Göttingen. / Bibliography: p. [303]-318.

A revision of the author's thesis, Göttingen. / Bibliography: p. [303]-318.

Thesis (M.S.)--Montana State University--Bozeman, 2005. / Typescript. Chairperson, Graduate Committee: Shi-Jie (Gary) Chen. Includes bibliographical references (leaves 89-99).

Η γλώσσα προγραμματισμού Scratch είναι ιδανική για την εισαγωγή στον προγραμματισμό. Η νέα αυτή γλώσσα ανήκει στο παράδειγμα του ταυτόχρονου προγραμματισμού. Στην εργασία αυτή περιγράφεται η σχεδίαση και η αξιολόγηση ενός εξαμηνιαίου μαθήματος για την εκμάθηση της Scratch με σκοπό αφενός να μελετηθεί ο τρόπος με τον οποίο οι αρχάριοι προγραμματιστές προσεγγίζουν το θέμα του συγχρονισμού και αφετέρου να διατυπωθούν προτάσεις για τη βελτίωση του μαθήματος. Η μεθοδολογία που εφαρμόστηκε είναι βασισμένη σε σχεδιασμό ερευνητική μεθοδολογία. / Scratch programming language is ideal for introductory programming courses. This new language follows the concurrent programming paradigm. Ιn the thesis the design and evaluation of a course for learning programming with Scratch is described. The approach that beginners programmers use for the necessary synchronization is studied and a new proposal for the laboratory course is presented. The design based research methodology is followed.