Yuh-Min Chen

Design and implementation of a collaborative engineering information system for allied concurrent engineering

Allied concurrent engineering is defined by unifying the concepts of virtual enterprise and concurrent engineering in the engineering processes. It aims to integrate the engineering activities and resources from different enterprises through enterprise alliances to respond to customer expectations quickly. The integration, management and sharing of engineering information is the basis for allied concurrent engineering. This paper presents a systematic approach, from domain investigation and functional requirement analysis, through system design and modelling to implementation of an engineering information system that makes use of various modelling techniques. The system aims at quickly providing the right information to the right place at the right time in the right formats throughout the inter-enterprise concurrent engineering processes to facilitate communication, coordination, control and integration of multi-enterprise concurrent product and process development. The result of this research will enable the practice of allied concurrent engineering and consequently help increase product development capability and quality, reduce development cycle time and cost, and hence increase product marketability.

Enabling collaborative product design through distributed engineering knowledge management

Collaborative product design (CPD) is a knowledge-intensive process that encompasses conceptual design, detailed design, engineering analysis, assembly design, process design, and performance evaluation. Each task involves various areas of knowledge and experience. However, successful collaborative product design depends on the ability to effectively manage and share engineering knowledge and experience throughout the entire development process. Consequently, the realization of distributed engineering knowledge management, which not only supports collaborative product design but also accumulates and utilizes corporate memory situated at various locations, has become one of the key tasks managed by industries. This paper presents a distributed engineering knowledge management approach for the practice of collaborative product design. In developing the proposed approach, a CPD-based engineering knowledge management methodology is first proposed under the concepts of knowledge management and collaboration. This methodology includes a knowledge management-oriented engineering management work model, a distributed engineering knowledge management framework, and rules and methods for managing engineering knowledge. The CPD-based engineering knowledge management system framework is designed, on the basis of this proposed methodology. Finally, a CPD-based engineering knowledge management system is developed using unified modeling language (UML) modeling techniques.

Development of a mechanism for ontology-based product lifecycle knowledge integration

Compared with relying on the efforts of various enterprises collaborating on product lifecycle activities, such as coordination, communication and control, the ability to effectively share product information and knowledge is more important. Therefore, how to best integrate such heterogeneous product knowledge distributed among various cooperating enterprises has become an extremely important knowledge management subjects associated with collaborative product lifecycle. This study develops a novel mechanism for integrating ontology-based product lifecycle knowledge to effectively integrate the heterogeneous product knowledge distributed among different enterprises during a products lifecycle, thereby facilitating sharing of this product knowledge. This study: (i) designed an integration and sharing process for collaborative product lifecycle knowledge, (ii) developed techniques associated with integration of ontology-based product lifecycle knowledge, and (iii) implemented an integration and sharing mechanism for ontology-based product lifecycle knowledge. In developing techniques associated with integration of ontology-based product lifecycle knowledge, which involves establishing a product lifecycle ontology, designing local ontology schema, designing an integration algorithm for ontology-based product lifecycle knowledge, and designing a searching method for ontology-based product lifecycle knowledge.

Computer-aided feature-based design for net shape manufacturing

Abstract Contemporary computer-based design tools are not suitable for concurrent engineering oriented product design due to (a) their particular and stand-alone functionality, (b) the lack of a capability to support interactive decision-making, and (c) the heavy involvement of designer expertise and experience. This paper presents a feature-based design for a manufacturing framework which is able to support the practice of concurrent engineering by providing functions designed specifically for net shape product design and on-line design guidance. Knowledge-based and object-oriented modeling technologies are employed to develop design evaluation facilities. An object-oriented product model, embedded with product design and process knowledge, is constructed and used for design evaluation. Geometric reasoning is performed on features, feature interactions, and overall shape to identify areas that may conflict with design principles. This paper concentrates on design for net shape manufacturing with an emphasis on die casting and injection molding processes. However, the proposed framework is general enough for other net shape processes by customizing process specific features and encoding process design rules.

Developing a trust evaluation method between co-workers in virtual project team for enabling resource sharing and collaboration

An increasing number of companies, especially those with knowledge-intensive RD such collaboration relies on efficient management of distributed resources, safe and timely resource sharing, and reliable trust evaluation mechanisms that facilitate the greatest degree of information sharing and minimize information transfer delays. This study first identifies VPT characteristics and the particular requirements of effective resource management and sharing. A VPT model is then presented. By applying this model, this study presents a trust evaluation method that assists VPT members in determining whether resource holders have made appropriate decisions to share resources with other VPT members. The proposed evaluation method comprises a trust evaluation between two VPT workers and a reliability evaluation of worker. Each resource can have a threshold that is a benchmark for resource sharing. The trust evaluation method for the proposed VPT model enables secure resource sharing across team and enterprise boundaries, facilitates collaboration, and enhances information transparency among team members.

Development of a concurrent mold design system: a knowledge-based approach

Abstract This paper presents research that establishes a systematic methodology and knowledge base for an injection-molding mold design in a concurrent engineering environment. This methodology is, in general, analogous to the methods of design for manufacturing, and is, however, in collaboration with activities of molding product design and mold manufacturing process planning. The practical goal of this research is twofold: to develop a mold-development process that facilitates concurrent engineering-based practice and to develop a knowledge-based design aid for injection-molding mold design that accommodates manufacturability concerns, as well as requirements of products. The research approach includes (i) process modeling and reengineering for concurrent mold design, (ii) identification of functional requirements with a computer-based system, (iii) system framework design, and (iv) system modeling and implementation. The framework supports concurrent engineering based mold design by providing advisory tools that are able to resolve relevant issues at the early stages of mold design. The results of this research will facilitate the rationalization and automation of the mold development process, thus improving the efficiency and quality of, and reducing the cost of, mold development.

Developing a semantic-enable information retrieval mechanism

The existing information retrieval systems are mostly keyword-based and retrieve relevant documents or information by matching keywords. Keyword-based search, in spite of its merits of expedient query for information and ease-of-use, has failed to represent the complete semantics contained in the content and has let to the retrieval failure. In a textual content, the authors intention is represented in a semantic format of various combinations of word-word relations that are comprehensible to human beings. Query constructed by descriptions in natural language best reflects querists intention. This study developed a semantic-enable information retrieval mechanism that handles the processing, recognition, extraction, extensions and matching of content semantics to achieve the following objectives: (1) to analyze and determine the semantic features of content, to develop a semantic pattern that represents semantic features of the content, and to structuralize and materialize semantic features; (2) to analyze users query and extend its implied semantics through semantic extension so as to identify more semantic features for matching; and (3) to generate contents with approximate semantics by matching against the extended query to provide correct contents to the querist. This mechanism is capable of improving the traditional problem of keyword search and enables the user to perform a semantic-based query and search for the required information, thereby improving the reusing and sharing of information.

A semantic-based approach to content abstraction and annotation for content management

In recent years, knowledge becomes the most important asset of individuals as well organizations, and determines the competitiveness of an enterprise. Content is a knowledge container that implies what human beings transform their knowledge in when they want to communicate with other people. Therefore, effective content management can achieve the goal and value of knowledge management. Content management activities are depending on meta-content which represents the content feature and are generated through the procedures of content abstraction and annotation. In general, the content creator utilizes words and logical combinations to express his intentions and concepts in semantic formats that are comprehensible to human beings. Accordingly, managing content from a semantic approach can effectively improve transparency and visibility of the content, and guides both the content creator and the user to engage in seamless, semantic-based communications and interactions. This study proposes a semantic-based content abstraction and annotation approach and a semantic pattern for bridging the semantic gaps of content management. Based on this approach, a semantic-driven content management environment that features a high interoperability of content can be constructed to accomplish the following goals and benefits: (1) effectively bridging semantic gaps in the existing content management systems; (2) delivering the right content to the right user at the right time; (3) bridging the semantic gaps for the content author and the customer to increase the efficiency of content management; and (4) realizing the acquisition, analysis, access, management, diffusion, interpretation, and innovation of knowledge.

Development of an access control model, system architecture and approaches for resource sharing in virtual enterprise

Secure information sharing is one of key factors for success of virtual enterprise (VE). The study identifies the characteristics of a VE and analyzes the requirements of a VE access control. A Virtual Enterprise Access Control (VEAC) model is proposed to handle resource management and sharing across each participating enterprise, which consists of a Project-based Access Control (PBAC) sub-model to manage public resources and a Role-based Access Control (RBAC) sub-model to manage private resources. The architecture of a VEAC model-based system is developed and consists of three core mechanisms including the Virtual Enterprise Access Control Center (VEACC), Security Gatekeeper (SG) and Global Certificate Authority Center (GCAC). Based on the system architecture, the study proposes certificate authentication, user authority and access control approaches to identify users identity on-line, update and search user authority lists, and access private and public resources. The results of this study will facilitate more secure resource sharing, and overcome cooperation barrier from trust among participating enterprises in VE.

Guidelines for developing effective Estimation of Distribution Algorithms in solving single machine scheduling problems

The goal of this research is to deduce important guidelines for designing effective Estimation of Distribution Algorithms (EDAs). These guidelines will enhance the designed algorithms in balancing the intensification and diversification effects of EDAs. Most EDAs have the advantage of incorporating probabilistic models which can generate chromosomes with the non-disruption of salient genes. This advantage, however, may cause the problem of the premature convergence of EDAs resulted in the probabilistic models no longer generating diversified solutions. In addition, due to overfitting of the search space, probabilistic models cannot really represent the general information of the population. Therefore, this research will deduce important guidelines through the convergency speed analysis of EDAs under different computational times for designing effective EDA algorithms. The major idea is to increase the population diversity gradually by hybridizing EDAs with other meta-heuristics and replacing the procedures of sampling new solutions. According to that, this research further proposes an Adaptive EA/G to improve the performance of EA/G. The proposed algorithm solves the single machine scheduling problems with earliness/tardiness cost in a just-in-time scheduling environment. The experimental results indicated that the Adaptive EA/G outperforms ACGA and EA/G statistically significant in different stopping criteria. This paper, hence, is of importance in the field of EDAs as well as for the researchers in studying the scheduling problems.