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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

Optimizing The Level Of Customization For Products In Mass Customization Systems

Spahi, Sami 01 January 2008 (has links)
Mass customization (MC) was developed to capitalize on the combined benefits of economies of scale and economies of scope. Balancing the tradeoffs involved in an MC system warrants the determination of the degree or the extent of customization. Most of the literature views the degree of customization as how early or how far the customer is integrated in the production cycle, which is defined as the order decoupling point. In this study we are addressing the degree of customization from a product structural perspective. There are two objectives in this research. The first is to develop a unit of measurement for the degree of customization of a product in an MC system. The second is to construct an optimization model to determine the level of customization that would best satisfy the organizational goals. The term "Magnitude of Customization" (MOC) has been introduced as a measuring unit for the degree of customization on a customization scale (CS). The MOC is based on the number of module options or the extent of customizable features per component in a product. To satisfy the second objective, an analytical model based on preemptive goal programming was developed. The model optimizes the solution as to how far an organization should customize a product to best satisfy its strategic goals. The model considers goals such as increasing the market share, and attaining a higher level of customer satisfaction, while keeping the risk or budget below a certain amount. A step-by-step algorithm is developed for the model application. A case study of an aluminum windows and doors company is used to verify and validate the model. A double panel sliding window is selected as the subject of our study. Information related to company goals and objectives vis-a-vis customization is gathered, through interviews and questionnaires, from the upper management including Operations, Marketing, and Finance Departments. The Window design and technical information are collected from the Manufacturing Department. The model and its solution provided specific recommendations on what to customize and to what degree to best satisfy primary strategic goals for the organization. Results from the model application shows that the company is able to meet the five goals that they had identified with two goals having a deviation of 4.7% and 6.6% from the targets. To achieve the stated goals, the model recommends an overall degree of customization of approximately 32.23% and delineates that to the component and feature levels. For validation, the model results are compared to the actual status of the company and the manufacturer's recommendation without prior information about the model outcome. The average difference, for attaining the same goals, is found to be 6.05%, at a standard deviation of 6.02% and variance of 36.29%, which is considered adequately close. The proposed model presents a framework that combines various research efforts into a flexible but encompassing method that can provide decision-makers with essential production planning guidelines in an MC setup. Finally, suggestions are provided as to how the model can be expanded and refined to include goal formulations that accommodate potential MC systems and technology advances. To the best of our knowledge, this research is a pioneer in quantifying customization in an MC environment and relating it to the organizational goals through modeling and optimization.
232

Design and Packaging of All-in-One Axle / Design och förpackning av allt-i-ett axeln

Talib, Alafiya, Singhal, Lakshay January 2023 (has links)
The aim of this thesis work is to design an electric axle that contains all the operational components, like the powertrain, suspension, brakes, and steering system. One of the requirements of this design work is to package all the axle components compactly in one single unit. This work is also carried out to assess the viability of assisting in the overall modularity of the chassis as modularity in commercial vehicles has become a popular trend in recent years due to the increasing market competition as well as the need for more sustainable products. The work has been carried out in three phases - research, conceptualization, and analysis. The research phase consisted of both market research on the existing products available commercially and a literature review of the various components of an axle to find feasible alternatives to the components currently being used in electric axles. In the conceptualization phase, the various e-axle concepts were compared using methods like PUGH’s matrix to eliminate concepts that did not seem feasible for the detailed design. Preliminary CAD models were designed for the One-motor solution and the In-wheel motor solution. The In-wheel motor solution was eliminated due to some critical limitations and the One-motor solution was chosen for the next sub-phase of detailed CAD modeling. This concept was then analysed using Finite Element analysis as well as kinematic analysis to get insights into the axle performance as well as to observe the load distribution on the axle during operation. / Målet med detta examensarbete är att designa en elektrisk axel som innehåller alla driftskomponenter, såsom kraftöverföring, fjädring, bromsar och styrning. Ett av kraven för denna design är att kompakt packa alla axelkomponenter i en enda enhet. Arbetet utförs också för att bedöma genomförbarheten av att bidra till den övergripande modulariteten hos chassit, eftersom modularitet inom kommersiella fordon har blivit en populär trend de senaste åren på grund av ökad marknadskonkurrens samt behovet av mer hållbara produkter. Arbetet har genomförts i tre faser - forskning, konceptualisering och analys. Forskningsfasen bestod av både marknadsundersökningar av befintliga produkter som finns kommersiellt tillgängliga och en litteraturgenomgång av olika delkomponenter i en axel för att hitta genomförbara alternativ till de komponenter som för närvarande används i elektriska axlar. I konceptualiseringsfasen jämfördes olika e-axelkoncept med hjälp av metoder som PUGH-matrisen för att eliminera koncept som inte verkade genomförbara för den detaljerade designen. Preliminära CAD-modeller designades för enmotorslösningen och in-wheel- motorlösningen. In-wheel-motorlösningen eliminerades på grund av vissa begränsningar, och enmotorslösningen valdes för nästa underfas av detaljerad CAD-modellering. Detta koncept analyserades sedan med hjälp av elementanalys samt kinematisk analys för att få insikter i axelns prestanda och observera belastningsfördelningen på axeln under drift.
233

DISCOVERY AND PRIORITIZATION OF BIOLOGICAL ENTITIES UNDERLYING COMPLEX DISORDERS BY PHENOME-GENOME NETWORK INTEGRATION

GUDIVADA, RANGA CHANDRA January 2007 (has links)
No description available.
234

On the Modularity of a System

Johansson, Per, Holmberg, Henric January 2010 (has links)
Den här uppsatsen behandlar skapandet och designen av en arkitektur över ett system för behandling av depression och andra psykiska sjukdomar via internet, kallat Melencolia. Ett av kraven för detta projekt är att skapa ett system som kan utökas i framtiden. Vi har härlett detta krav till begreppet modularitet och för att skapa en modulär arkitektur för Melencolia har vi undersökt vad begreppet innebär och härlett det till att vara ett kvalitetsdrag hos flera kvalitetsattribut däribland ”maintainability” och ”reusability”. Med hjälp av ”Attribute Driven Design” kan en arkitektur skapas som fokuserar kring en viss typ av kvalitetsattribut. Eftersom modularitet inte är ett kvalitetsattribut utan en kvalitetsegenskap har vi varit tvungna att ändra indata till denna metod, från kvalitetsattribut till kvalitetsegenskap. Vidare har vi härlett och lagt fram en ny metod för att mäta kvalitetsegenskaper i en mjukvaruarkikektur.Slutligen har vi använt vår metod för att mäta graden av modularitet i Melencolias arkitektur. / This thesis considers the problem of creating and designing an architecture for a software project that will result in a system for treatment of depression on the Internet. One of the requirements for this project, named by Melencolia, is to create a system which can be extended in the future. From this requirement we have derived the concept of modularity. In order to create a modular architecture we have concluded that modularity is a quality characteristic of multiple quality attributes such as "maintainability" and "reusability".We deploy Attribute-Driven Design (ADD) in this Melencolia project. By doing this, an architecture that is focused around modularity can be created. Since modularity is not a quality attribute, but rather a quality characteristic, we had to change the input to ADD from a quality attribute to a quality characteristic.Furthermore, we derive and propose a new method for quality characteristic evaluation of software architectures.Finally we apply our aforementioned method on the architecture of Melencolia and by doing this we get an indication on how well our proposed architecture satisfies modularity.
235

EFFICIENT INFERENCE AND DOMINANT-SET BASED CLUSTERING FOR FUNCTIONAL DATA

Xiang Wang (18396603) 03 June 2024 (has links)
<p dir="ltr">This dissertation addresses three progressively fundamental problems for functional data analysis: (1) To do efficient inference for the functional mean model accounting for within-subject correlation, we propose the refined and bias-corrected empirical likelihood method. (2) To identify functional subjects potentially from different populations, we propose the dominant-set based unsupervised clustering method using the similarity matrix. (3) To learn the similarity matrix from various similarity metrics for functional data clustering, we propose the modularity guided and dominant-set based semi-supervised clustering method.</p><p dir="ltr">In the first problem, the empirical likelihood method is utilized to do inference for the mean function of functional data by constructing the refined and bias-corrected estimating equation. The proposed estimating equation not only improves efficiency but also enables practically feasible empirical likelihood inference by properly incorporating within-subject correlation, which has not been achieved by previous studies.</p><p dir="ltr">In the second problem, the dominant-set based unsupervised clustering method is proposed to maximize the within-cluster similarity and applied to functional data with a flexible choice of similarity measures between curves. The proposed unsupervised clustering method is a hierarchical bipartition procedure under the penalized optimization framework with the tuning parameter selected by maximizing the clustering criterion called modularity of the resulting two clusters, which is inspired by the concept of dominant set in graph theory and solved by replicator dynamics in game theory. The advantage offered by this approach is not only robust to imbalanced sizes of groups but also to outliers, which overcomes the limitation of many existing clustering methods.</p><p dir="ltr">In the third problem, the metric-based semi-supervised clustering method is proposed with similarity metric learned by modularity maximization and followed by the above proposed dominant-set based clustering procedure. Under semi-supervised setting where some clustering memberships are known, the goal is to determine the best linear combination of candidate similarity metrics as the final metric to enhance the clustering performance. Besides the global metric-based algorithm, another algorithm is also proposed to learn individual metrics for each cluster, which permits overlapping membership for the clustering. This is innovatively different from many existing methods. This method is superiorly applicable to functional data with various similarity metrics between functional curves, while also exhibiting robustness to imbalanced sizes of groups, which are intrinsic to the dominant-set based clustering approach.</p><p dir="ltr">In all three problems, the advantages of the proposed methods are demonstrated through extensive empirical investigations using simulations as well as real data applications.</p>
236

A HIGH-DEMAND TELEMETRY SYSTEM THAT MAXIMISES FUTURE EXPANSION AT MINIMUM LIFE-CYCLE COST

Crouch, Viv, Goldstein, Anna 10 1900 (has links)
International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California / The Aircraft Research and Development Unit (ARDU) of the Royal Australian Air Force (RAAF) is the only agency in Australia that performs the full spectrum of military flight testing and is the new custodian of the instrumented weapons range at Woomera. Receiving early attention will be the upgrade and integration of ARDU's telemetry systems with the meteorological and tracking data acquisition capabilities at Woomera to minimize overhead and data turnaround time. To achieve these goals, maximum modularity, extensibility, and product interoperability is being sought in the proposed architecture of all the systems that will need to cooperate on the forecast test programmes. These goals are also driven by the need to be responsive to a wide variety of tasks which presently include structural flight testing of fighter and training aircraft, weapons systems performance evaluation on a variety of combatant aircraft, and a host of other tasks associated with all fixed and rotary wing aircraft in the Army and Air Force inventory. Of all these tasks however, ARDU sees that responsiveness to future testing of F-111Cs fitted with unique Digital Flight Control Systems along with USAF standard F-111Gs may place the most significant demands on data handling —particularly in regard to providing an avionics bus diagnostic capability when performing Operational Flight Programme (OFP) changes to the mission computers. With the timely assistance and advice of Loral Test & Information Systems, who has long-term experience in supporting USAF F-111 test programmes, ARDU is confident of making wise design decisions that will provide the desired flexibility and, at the same time, minimize life-cycle costs by ensuring compliance with the appropriate telemetry and open systems standards. As well, via cooperative agreements with the USAF, the potential exists to acquire proven software products without needing to fund the development costs already absorbed by the USAF. This paper presents ARDU's perception of future needs, a view by LTIS of how best to meet those needs, and, based on ARDU data, a view of how LTIS' proposal will satisfy the requirement to provide maximum extensibility with minimum life-cycle costs.
237

Evolvability : a formal approach

Gallagher, Alexis January 2009 (has links)
This dissertation clarifies the concept of evolvability, the increased capacity of some organisms or systems to support evolution, especially the evolution of life-like complexity. I survey the literature, which is spread over the fields of population genetics, developmental biology, artificial life, and microbial and molecular evolution. Finding that researchers have often used the term vaguely and incompatibly I identify five distinct kinds or senses of evolvability. I also identify five key constituent ideas, which I discuss in the context of organismic evolvability, a sense of evolvability with deep roots in the traditional fields of animal development and macroevolution. In these fields research into evolvability has historically been hampered by an insufficiently detailed knowledge of development. Research in molecular evolution has produced a thorough knowledge of the folding of RNA into secondary structure, which can be regarded as a model of development. This has motivated new approaches to evolvability based on representing development via a single genotype-phenotype mapping function. I build on these approaches to invent new mathematical methods to formalise the traditional ideas. I create an exact model illustrating a classic example of evolvability, the capacity for repeated segmentation and simple modularity. I analyse this with two new formal approaches. First is the genospace algebra, a propositional calculus based on graph theory. It is a formal language for describing genotype-phenotype maps. It provides a system for making calculations, proofs, and diagrams about mutational structures in genotype space, and it is flexible enough to allow description at arbitrary degrees of resolution. Second is a pair of concepts, the genetic leverage and the genetic fulcrum. The leverage provides a crude numerical measure of evolvability, and the fulcrum provides a heuristic for identifying the genomic and developmental causes of evolvability. Besides its specific relevance to diversification and development, evolvability is also crucial to the fundamental question of how evolution produces ordinary biological life. Simulation systems that implement only a conventional textbook model of evolution -– systems possessing only variation, inheritance, and selection –- fail to evolve anything resembling the complexity of the biological world. Research into evolvability is our best bet to illuminate the "missing ingredient" for life-like evolution.
238

Sobre o uso da gramática de dependência extensível na geração de língua natural: questões de generalidade, instanciabilidade e complexidade / On the application of extensible dependency grammar to natural language generation: generality, instantiability and complexity issues

Pelizzoni, Jorge Marques 29 August 2008 (has links)
A Geração de Língua Natural (GLN) ocupa-se de atribuir forma lingüística a dados em representação não-lingüística (Reiter & Dale, 2000); a Realização Lingüística (RL), por sua vez, reúne as subtarefas da GLN estritamente dependentes das especificidades da língua-alvo. Este trabalho objetiva a investigação em RL, uma de cujas aplicações mais proeminentes é a construção de módulos geradores de língua-alvo na tradução automática baseada em transferência semântica. Partimos da identificação de três requisitos fundamentais para modelos de RL quais sejam generalidade, instanciabilidade e complexidade e da tensão entre esses requisitos no estado da arte. Argumentamos pela relevância da avaliação formal dos modelos da literatura contra esses critérios e focalizamos em modelos baseados em restrições (Schulte, 2002) como promissores para reconciliar os três requisitos. Nesta classe de modelos, identificamos o recente modelo de Debusmann (2006) Extensible Dependency Grammar (XDG) e sua implementação - o XDG Development Toolkit (XDK) - como uma plataforma especialmente promissora para o desenvolvimento em RL, apesar de jamais utilizada para tal. Nossas contribuições práticas se resumem ao esforço de tornar o XDK mais eficiente e uma formulação da disjunção inerente à lexicalização adequada à XDG, demonstrando suas potenciais vantagens numa sistema de GLN mais completo / Natural Language Generation (NLG) concerns assigning linguistic form to data in nonlinguistic representation (Reiter & Dale, 2000); Linguistic Realization (LR), in turn, comprises all strictly target language-dependent NLG tasks. This work looks into RL systems from the perspective of three fundamental requirements - namely generality, instantiability, and complexity and the tension between them in the state of the art. We argue for the formal evaluation of models against these criteria and focus on constraint-based models (Schulte, 2002) as tools to reconcile them. In this class of models we identify the recent development of Debusmann (2006) - Extensible Dependency Grammar (XDG) - and its implementation - the XDG Development Toolkit (XDK) - as an especially promising platform for RL work, in spite of never having been used as such. Our practical contributions comprehend a successful effort to make the XDK more efficient and a formulation of lexicalization disjunction suitable to XDG, illustrating its potential advantages in a full-fledged NLG system
239

Preuves par raffinement de programmes avec pointeurs / Proofs by refinement of programs with pointers

Tafat, Asma 06 September 2013 (has links)
Le but de cette thèse est de spécifier et prouver des programmes avec pointeurs, tels que des programmes C, en utilisant des techniques de raffinement. L’approche proposée permet de faire un compromis entre les techniques complexes qui existent dans la littérature et ce qui est utilisable dans l’industrie, en conciliant légèreté des annotations et restrictions sur les alias. Nous définissons, dans un premier temps, un langage d’étude, qui s’inspire du langage C, et dans lequel le seul type de données mutable possible est le type des structures, auquel on accède uniquement à travers des pointeurs. Afin de structurer nos programmes, nous munissons notre langage d’une notion de module et des concepts issus de la théorie du raffinement tels que les variables abstraites que nous formalisons par des champs modèle, et les invariants de collage. Ceci nous permet d’écrire des programmes structurés en composants. L’introduction des invariants de données dans notre langage soulève des problématiques liées au partage de pointeurs. En effet, en cas d’alias, on risque de ne plus pouvoir garantir la validité de l’invariant de données d’une structure. Nous interdisons, alors l’aliasing (le partage de référence) dans notre langage. Pour contrôler les accès à la mémoire, nous définissons un système de type, basé sur la notion de régions. Cette contribution s’inspire de la théorie du raffinement et a pour but, de rendre les programmes les plus modulaires possible et leurs preuves les plus automatiques possible. Nous définissons, sur ce langage, un mécanisme de génération d’obligations de preuve en proposant un calcul de plus faible précondition incorporant du raffinement. Nous prouvons ensuite, la correction de ce mécanisme de génération d’obligations de preuve par une méthode originale, fondée sur la notion de sémantique bloquante, qui s’apparente à une preuve de type soundness et qui consiste donc, à prouver la préservation puis le progrès de ce calcul. Nous étendons, dans un deuxième temps, notre langage en levant partiellement la restriction liée au partage de références. Nous permettons, notamment, le partage de références lorsqu’aucun invariant de données n’est associé au type structure référencé. De plus, nous introduisons le type des tableaux, ainsi que les variables globales et l’affectation qui ne font pas partie du langage noyau. Pour chacune des extensions citées ci-dessus, nous étendons la définition et la preuve de correction du calcul de plus faible précondition en conséquence. Nous proposons enfin, une implantation de cette approche sous forme d’un greffon de Frama-C (http://frama-c.com/). Nous expérimentons notre implantation sur des exemples de modules implantant des structures de données complexes, en particulier des défis issus du challenge VACID0 (http://vacid. codeplex.com/), à savoir les tableaux creux (Sparse Array) et les tas binaires. / The purpose of this thesis is to specify and prove programs with pointers, such as C programs, using refinement techniques. The proposed approach allows a compromise between the complexe methods that exist in the literature and what is used in industry, reconciling lightness annotations and restrictions on the alias. We define, firstly, a language study, based on the C language, in which the only type of mutable data allowed is the type of structures, which can be accessed only through pointers. In order to structure our programs, we bring our language with a module notion and concepts issue from a refinement theory such as abstract variables that we formalize by model fields and gluing invariants. This allows us to write programs structured by components. Introducing invariants in our language raises issues related to aliasing. Indeed, in presence of alias, we might not be able to guarantee the validity of the invariant data structure. We forbid then the aliasing in our language. To control memory access, we define a type system based on the concept of regions. This contribution is based on the theory and refinement. It aims to make programs as modular as possible and proofs as automatic as possible. We define on this language, a mechanism for generation of proof obligations by proposing a weakest precondition calculus incorporating refinement. Next we prove the correction of this proof obligations generation mechnaism by an original method based on the concept of blocking semantic, which is similar to a proof of type soundness, and consists therefore, to proove the preservation and the progress of the defined calculus. Secondly, we extend our language by, partially, lifting the restrictions related to aliasing. We allow, in particular, sharing when no invariant is associated to the referenced data structure. In addition, we introduce the type of arrays, global variables, and assignment that are not part of the core language. For each of the extensions mentioned above, we extend the definition and correctness proof of the weakest precondition calculus accordingly. Finally, we propose an implementation of this approach as a Frama-C plugin(http ://frama-c.com/). We experimente our implantation on examples of modules implementing complex data structures, especially the challenges from the challenge VACID0 (http ://vacid. Codeplex.com /), namely sparse srrays and binary heaps.
240

工業用電腦主機板的快速客製化服務之研究-以研華科技為例 / To Study The Fast Customization Service of Industrial PC Maker - A Case Study for Advantech Co., Ltd

廖漢雄, Barry Liaw Unknown Date (has links)
本研究針對工業電腦產業,探索其創新產品服務:快速客製化(半客製化)服務的兩大產品服務模組化系統SOM(System On Module)及接單設計服務DTOS(Design To Order Service)-客製底板CSB的客製化服務之間的關聯影響,及對快速客製化(半客製化)服務的影響及關聯性。本研究以個案訪談法,以研華科技為研究對象;加上部份的問卷調查,為主要的研究方法。   本研究歸納分析研究發現如下:   【研究發現1】共通性模組的共通性程度會影響快速客製化服務績效   【研究發現2】變異性模組的變異性程度會影響快速客製化服務績效   【研究發現3】模組的介面標準化程度會影響快速客製化服務績效   【研究發現4】設計延遲會影響快速客製化服務績效   【研究發現5】最佳資源統治形式會影響快速客製化服務績效   【研究發現6】接單後生產機制會影響快速客製化服務績效   【研究發現7】共通性模組的共通性程度會影響設計延遲   【研究發現8】變異性模組的變異性程度會影響最佳資源統治形式   【研究發現9】模組化是接單後生產機制的必備條件   研究結果發現:快速客製化服務是結合「快速設計客製化」及「大量客製化」的新興事業模式;並發現模組化及設計延遲理論對快速客製化服務的重大影響。   因此本研究建議:廠商應該致力於推動模組化系統SOM的產業標準化,運用延遲理論於接單設計DTOS及接單生產BTO服務,及運用交易成本理論於最佳資源統治形式來提高客製底板CSB快速客製化服務的績效。 / This research focused on studying the new business model for Fast Customization Service which is the combination of Fast Design Customization Service and Mass Customization Service.   The research result shows that Fast Customization Service is significantly influenced by “Modularity” and “Design Postponement” .   The Author suggests that the IPC makers should endeavor for promoting the industrial standardization of SOM (System On Module) , implementing Postponement theory into DTOS (Design To Order Service) and BTO (Build To Order) , and implementing Transaction-Cost Theory into the best Governance Structure .

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