http://hdl.handle.net/10397/946 Search the Channel search http://repository.lib.polyu.edu.hk/jspui/simple-search http://hdl.handle.net/10397/5710 Title: A semantically annotated multi-faceted ontology modeling for supporting product family design<br/><br/>Authors: Lim, Soon Chong Johnson<br/><br/>Abstract: Product family design is one of the prevailing approaches for product realization in mass customization paradigm. With the ever-increasing product offerings in consumer market, a good product family modeling scheme is a basic requirement for further complex decision making where the incorporation of various design aspects, e.g. product function, marketing and manufacturing wise, for product family analysis are deemed important but challenging. Specifically, the issue of information management in product family design, that is related to an efficient and effective storage, sharing and timely retrieval of design information, has become more complicated. Product family modeling schema reported in the literature generally stress the component aspects of a product family and its analysis, with limited capability to model complex multiple inter-relationships and semantic annotations amongst physical components under various design facets. Due to this limitation, existing schemes are constrained to support intelligent PFD tasks, e.g. faceted component analysis based on vague, contextual design requirements like customer voices. In order to cope with these issues, ontology-based representation is identified as a promising solution especially in a semantically rich environment. Nevertheless, ontology development in design engineering demands a great deal of time commitment and human effort to digest complex design information. When a large variety of products are available, particularly in the consumer market, a more efficient method for building a product family ontology with the incorporation of multi-faceted semantic information is highly desirable. This thesis proposes a multi-faceted semantic tagging approach that is able to automatically suggest semantically related annotations based on design and manufacturing corpus. Technically, a semantic relatedness based ranking approach, FacetRank, is introduced in this thesis. Evaluation results using an annotated dataset indicate that FacetRank is capable of extracting salient terms from a collection of documents. Based on a faceted modeling approach, dictionary-like semantic descriptions can be generated for an input term where faceted semantic descriptors, e.g. faceted indicators and semantically similar key terms can be suggested. Using such an annotation approach, this thesis suggests a semi-automatic methodology of developing a semantically annotated multi-faceted product family ontology (MFPFO). The detailed steps of building such ontology are discussed with the feasibility of such a methodology exemplified using a family of laptop computers.; Utilizing the aforementioned ontology, this thesis also presents a new perspective towards ontology-based product family design. Specifically, a faceted information search and retrieval framework based on a semantically annotated MFPFO is proposed. Faceted concept ranking (FCR) approach for ontology-based faceted component search is suggested to generate rank values for component search results corresponding to complex design requirements. From the component ranking results, a platform selection approach is proposed to evaluate the suitability of platform choices and platform change assessment under multi-faceted design considerations. Utilizing the search ranking results and new commonality metrics, optimal selection of components via a multi-objective design optimization is presented. A case study of three laptop computer design that involves four laptop computer families is demonstrated with promising outcomes. Finally, the advantages, issues and future works possible are also critically discussed in this thesis.<br/><br/>Description: xiv, 207 leaves : col. ill. ; 30 cm.; PolyU Library Call No.: [THS] LG51 .H577P ISE 2012 Lim Sun, 01 Jan 2012 00:00:00 GMT http://hdl.handle.net/10397/5709 Title: A study of the relationship between intellectual capital and innovation performance based on complexity theory<br/><br/>Authors: Fan Ng, Irene Yuen Han<br/><br/>Abstract: Systemic innovation capability is the key driver of sustainable growth and competitive advantage in enterprises. However, imitating other innovative organization and best practices does not guarantee success. Business organization can be described as a complex system in a competitive business environment that constantly changes. Each organization can be analogically viewed as striving to reach higher performance on its own rugged landscape. Nevertheless, each unique landscape is formed by the characteristics of an organization that are intangible, difficult to uncover and measure, and cannot be altered in a simple mechanical way. Organizational DNA has been used to describe such complex and organic nature of an organization in equivalent to living organisms. Organizational DNA is particularly crucial for innovation. Intellectual capital is defined as all intangible resources of an organization that, when combined, will produce future benefits. Research studies have shown that there is a tight relationship between intellectual capital and innovation performance. It is appropriate to use intellectual capital as the organizational DNA for innovation studies. The aim of the study is to construct an innovation assessment model based on Kauffman's biological model. Strategies utilizing intellectual capital for better innovation performance can be simulated, analyzed and implemented.; This study adopted the design science research methodology with cycles of empirical research and model validation. Combinations of quantitative and qualitative research approaches were applied. Three studies were carried out in the Information and Communication Technology industry in different geographical locations. Each study comprised a survey, statistical analysis and model simulation. Survey questionnaires were designed based on literature review and prior studies in intellectual capital and innovation. Partial Least Square regression was used with its capability of multicollinearity identification, nonlinear path estimation and the relaxed requirement of sample data size. Six main intellectual capital components were proposed and confirmed: self-efficacy of knowledge workers, transformational leadership, innovative culture, systems and processes, internal and external social networks. Their nonlinear relationships among one another and with innovation performance were verified. The findings were validated through interviews. These statistical findings were then input into a simulation model built based on the Kauffman's NK model. The NK model was an evolutionary biology model for stochastic combinatorial optimization. The original model described the interactions between genes as Boolean relationships. It was not sufficient to describe the interrelationships in organizational studies. The model was extended by using the correlation matrix from the statistical analysis as the interaction matrix of the NK model. A comparative study of two groups within the same organization was carried out and demonstrated that their organizational DNA fingerprints were unique, and different innovation strategies were needed. This study is significant as it offers a systemic approach to the interdisciplinary study of organizational DNA and innovation with a pioneering use of an intellectual capital framework. It contributes to the field of innovation management with a new attempt of its kind to integrate management research and mathematical simulation model to cover both the qualitative and quantitative aspects. In practice, it enables organizations to formulate effective management strategies for innovation performance.<br/><br/>Description: xi, 234 p. : ill. ; 30 cm.; PolyU Library Call No.: [THS] LG51 .H577P ISE 2012 Fan Ng Sun, 01 Jan 2012 00:00:00 GMT http://hdl.handle.net/10397/5535 Title: A methodology for integrating supplier selection with product line design<br/><br/>Authors: Deng, Shuofeng Brian<br/><br/>Abstract: Product line design involves design of various product variants under a product line which aims to satisfy the needs of various market segments. In the development of product lines, it is quite common for companies to adopt sourcing strategy nowadays for reducing product cost and development time, and improving product quality. One major issue of the sourcing is supplier selection. Previous studies have shown that companies commonly spent 60% of product cost on sourcing. Conventionally, product design and supplier selection are dealt with separately. Product design is first performed and then suppliers are selected to provide the required components or product modules. Various studies have been conducted in the areas of product line design and supply chain issues. However, only few studies found so far have investigated the optimal product line design together with supplier selection consideration. This project aims to investigate the integration of product line design with supplier selection issue. In this research, a methodology for integrating supplier selection with product line design is proposed. The proposed methodology is able to make up the deficiencies of the previously related studies, which include (1) prices of product variants are pre-defined; (2) only single objective is considered in the integrated problem; and (3) being unable to determine market positions of product variants. The proposed methodology involves the following steps. In the methodology, the customer preferences and their perceptions of competitive products are collected first through a market survey. Then, a joint-space map is constructed, and market share models, cost models, and quality and performance models are developed. The next step is to formulate an optimization model for determining the specifications of product variants of the product line such that the profit, quality and performance of the product line can be maximized. Finally, the optimization problem is solved using a multi-objective genetic algorithm. A case study of the product line design of portable computers was conducted to illustrate the effectiveness of the proposed methodology. The results have shown that optimal product line design with a consideration of supplier selection can be determined, and the specifications of the product variants can be generated. On the other hand, suppliers of components and modules can be selected with the considerations of minimum sourcing cost and maximum performance and quality of products. Price and position of the product variants can also be estimated. The methodology used in the study enables the effective joint decision making of product line design and supplier selection.<br/><br/>Description: xv, 149 leaves : ill. ; 30 cm.; PolyU Library Call No.: [THS] LG51 .H577M ISE 2012 Deng Sun, 01 Jan 2012 00:00:00 GMT http://hdl.handle.net/10397/5534 Title: Failure prediction of dental restoration using a CT-based finite element and damage mechanics approach<br/><br/>Authors: Chan, Yiu Pong<br/><br/>Abstract: To perform dental research on living subjects is expensive and needs to take ethical issues into account. Usage of computer simulation offers a better alternative with the capability of detailed stress analysis. In this study, a computational approach has been developed for failure prediction of dental restoration so that experimental effort can be minimized. The unit cell modeling method has been applied to predict the constitutive relations of dental composites, enamel and dentin. For most dental composites, particles have high loading and are non-spherical in shape, so a CAD-based modeling technique has been utilized to assist in the preparation of the unit cell models. Through employing the inter-part parametric assembly modeling characteristics of CAD tools, modeling of 3D triphasic unit cells with various particle morphologies and particle volume fractions can be achieved effectively and efficiently. The particles are packed using body centered cubic (BCC) or face centered cubic (FCC) packing architectures instead of traditional simple cubic (SC) architecture which has a low packing efficiency. The effect of interfacial debonding damage on the mechanical behavior of a dental composite has been predicted with the application of FE analysis. The mechanical behavior includes elastic modulus, tensile strength, and stress-strain relations for different particle morphologies and volume fraction cases. In addition, the stress concentration, stress distribution, and damage mechanism of the composite at the micro-scale have been predicted. In view of the hierarchical structure of enamel and dentin, columnar unit cell models have been designed to determine the anisotropic mechanical behavior. The model for enamel consists of rod and interrod constituents, peritubular and intertubular constituents are used for dentin. In this project, a new method, which integrates nanoindentation, finite element modeling, and artificial neural network techniques, is proposed to determine the elastoplastic stress-strain relations of the four constituents. Thus, the resulting mechanical properties of enamel and dentin in multi-scale include their anisotropic elastoplastic mechanical description parameters and the isotropic elastoplastic stress-strain relations of their four constituents.; To build up a solid computational model of a tooth and its corresponding mandible, a method has been proposed to construct 3D models from 2D scanned images. The models established using the proposed method are characterized by the ease of performing modifications. Facilitated by the CAD tools, the 3D tooth model has been virtually restored with a Class II mesio-occlusal (MO) restoration. This is done through five procedures, i.e. data point extraction, tissue surfaces construction, NURBS object modeling, assembly modeling, and FE model construction. The generated mandible assists in defining the boundary conditions of the tooth model. The tooth model is triphasic, including the enamel, dentin, and pulp phases. The determined anisotropic elastoplastic mechanical properties of enamel and dentin have also been incorporated into the model. Concerning the radial variation structure of the enamel and dentin, the tooth model has been partitioned into 18 regions, with a specific local coordinate system for each region. Stress analysis and failure prediction of the restoration have then been conducted using the established 3D assembly FE model. The simulation result showing the interfacial debonding occurred once the mastication loading exceeded a critical value of 140N is in a good agreement with the experimental findings. The deliverables of the proposed method in modeling mechanical properties using unit cell models can facilitate the design of dental composites and other particulate reinforced composites systematically rather than performing development experimentally by means of trial-and-error. Regarding the method used to determine the mechanical properties of the micro-scale constituents of enamel and dentin, it can also benefit other applications involving the determination of the elastoplastic mechanical properties of isotropic materials having small volume. For the established 3D assembly FE model, it also can be applied to other research studies where a tooth model is required. The application of the new method in constructing 3D FE models from 2D scanned images is not limited to the dental industry but also to other medical applications. It can be applied in creating patient-specific models of any body tissue part using CT scanning images.<br/><br/>Description: xvi, 174 leaves : ill. ; 30 cm.; PolyU Library Call No.: [THS] LG51 .H577P ISE 2012 Chan Sun, 01 Jan 2012 00:00:00 GMT