published_or_final_version / Business Administration / Master / Master of Business Administration

Recent advancements in sensory devices are presenting various opportunities for widespread applications of wireless sensor networks (WSNs). The most distinguishing characteristic of a WSN is the fact that its sensors have nite and non-renewable energy resources. Many research e orts aim at developing energy e cient network topology and routing schemes for prolonging the network lifetime. However, we notice that, in the majority of the literature, topology control and routing problems are handled separately, thus overlooking the interrelationships among them. In this dissertation, we consider an integrated topology control and routing problem in WSNs which are unique type of data gathering networks characterized by limited energy resources at the sensor nodes distributed over the network. We suggest an underlying hierarchical topology and routing structure that aims to achieve the most prolonged network lifetime via e cient use of limited energy resources and addressing operational speci cities of WSNs such as communication-computation trade-o , data aggregation, and multi-hop data transfer for better energy e ciency. We develop and examine three di erent objectives and their associated mathematical models that de- ne alternative policies to be employed in each period of a deployment cycle for the purpose of maximizing the number of periods so that the network lifetime is prolonged. On the methodology side, we develop e ective solution approaches that are based on decomposition techniques, heuristics and parallel heuristic algorithms. Furthermore, we devise visualization tools to support our optimization e orts and demonstrate that visualization can be very helpful in solving larger and realistic problems with dynamic nature. This dissertation research provides novel analytical models and solution methodologies for important practical problems in WSNs. The solution algorithms developed herein will also contribute to the generalized mixed-discrete optimization problem, especially for the problems with similar characteristics.

This dissertation in practice utilized a sequential mixed methods research design to investigate the performance or exclusion of instructional design activities commonly prescribed by instructional design models during a typical instructional design project. The purpose of this study was to compare the performance of instructional design activities by practicing instructional designers with the performance of an experienced instructional designer to determine if instructional design models are being used to guide the practice of instructional design. In this study, quantitative data was collected from a sample of 224 instructional designers to determine the activities routinely performed and excluded from typical projects. Qualitative data was collected from a single case study of an instructional design project to assess whether or not the performance or exclusion of the same instructional design activities were identified in the work of an experienced instructional designer. Analysis of the data revealed the activities that are not routinely performed by instructional designers, reasons for the exclusion of activities, and possible factors for the decisions to exclude activities. The findings of this study indicate instructional designers may be sacrificing the quality and effectiveness of instruction in an attempt to increase the pace and reduce the cost of the instructional design process. The study concluded that instructional designers are not following the prescriptions of instructional design models during the practice of instructional design by routinely eliminating the fundamental activities involving the development of learner assessments, the performance of formative evaluations during the instructional design process, and summative evaluations after the implementation of the instruction.

no / Demand for more sophisticated models to meet big data expectations require significant data repository obligations, operating concurrently in higher-level applications. Current models provide only disjointed modelling paradigms. The proposed framework addresses the need for higher-level abstraction, using low-level logic in the form of axioms, from which higher-level functionality is logically derived. The framework facilitates definition and usage of subjective structures across the cyber-physical system domain, and is intended to converge the range of heterogeneous data-driven objects.

Product success is a major goal of designing and design research. Designing involves developing systems. A system interacts with its environment to satisfy its requirements. Therefore, designing should involve developing the concept of both the system and its surrounding. Depending on how the concept of the system changes will impinge on the concept of the environment, and vice-versa; design must co-evolve the concepts of both the system and its environment to adapt them to each other. A comprehensive review of literature on designing to explore the use of system-environment view in designing revealed that while the concept of systems is used by many design models, implicitly or explicitly, the concept of environment is rarely used as an evolvable construct in designing. Activities, outcomes, requirement-solution and system-environment views play a significant role in product success. Thus, it is important to explicitly address these views in designing. Further, integration of these views is important for explaining various complex characteristics of designing such as requirement-solution co-evolution and system-environment co-evolution. Integration of views is important also for mapping the steps in design models using these views, so as to be able to characterize design models, or benchmark one design model against another. Literature has been reviewed to identify the constructs in these views that are essential for representing the design process. Srinivasan and Chakrabarti [2010] had earlier developed a model of designing by integrating three of these views: activities, outcomes, and requirement-solution. However, this model did not incorporate the system-environment view. In this thesis, a system-environment view is developed, with both the system and environment as explicit and evolvable constructs in designing. The thesis then proposed an extended, integrated model of designing which combines the constructs of the identified views of activities, outcomes, requirement-solution and system-environment. The proposed model is empirically validated using protocols from six design sessions; the sesessions had been undertaken well before the proposed model was developed.Validation involved checking whether or not instances of all the constructs in the model are naturally present in these design sessions, and whether or not every event in these design sessions could be described using the constructs of the proposed model. Further, the explanatory power of the proposed model is illustrated by explaining how system-environment co-evolution and requirement-solution co-evolution occur during the design sessions captured in the protocols. Also, a standard prescriptive approach to designing –Pahl and Beitz approach – is used to demonstrate how a design model can be mapped using the constructs of the proposed model–the first step to characterizing or benchmarking design models.

Doctor of Philosophy / Department of Computing and Information Sciences / Scott A. DeLoach / Organization-based Multiagent Systems (OMAS) have been viewed as an effective paradigm for addressing the design challenges posed by today’s complex systems. In those systems, the organizational perspective is the main abstraction, which provides a clear separation between agents and systems, allowing a reduction in the complexity of the overall system. To ease the development of OMAS, several methodologies have been proposed. Unfortunately, those methodologies typically require the designer to handle system complexity alone, which tends to lead to ad-hoc designs that are not scalable and are difficult to maintain. Moreover, designing organizations for large multiagent systems is a complex and time-consuming task; design models quickly become unwieldy and thus hard to develop. To cope with theses issues, a framework for organization-based multiagent system designs based on separation of concerns and composition principles is proposed. The framework uses category theory tools to construct a formal composition framework using core models from the Organization-based Multiagent Software Engineering (O-MASE) framework. I propose a formalization of these models that are then used to establish a reusable design approach for OMAS. This approach allows designers to design large multiagent organizations by reusing smaller composable organizations that are developed separately, thus providing them with a scalable approach for designing large and complex OMAS. In this dissertation, the process of formalizing and composing multiagent organizations is discussed. In addition, I propose a service-oriented approach for building autonomous, adaptive multiagent systems. Finally, as a proof of concept, I develop two real world examples from the domain of cooperative robotics and wireless sensor networks.

Improvement of performance has become ever more critical to construction project success and has been subject to a considerable amount of research and attention over the past two decades. In this regard, the Saudi Ministry of Interior (SMoI) has adopted a new approach - Standard Design Model (SDM) - for the development of its construction programme to successfully manage its complex project portfolio and improve project performance. The SMoI-SDM approach is based on the standardisation of design, material specifications, contract documents and processes. It is anticipated that many lessons will be learnt due to the re-use of SDMs for future projects as well as sharing learning between on-going projects, thus leading to continuous project performance improvement. The aim of this research is to develop a framework for improving the performance of SDMs in SMoI projects. A qualitative case study approach was adopted to provide an in-depth insight into the current performance of SDM projects and identify critical success factors (CSFs) affecting the process of improvement of SDMs project performance. Four case studies were selected involving two on-going and two completed projects. Three key themes were identified from the case studies analysis; these are: adaptability of SDMs to context; contract management; and construction management. Consequently, a framework was developed to improve SDM projects performance as well as the expected performance improvement curve that results from the cumulative learning and experience. The framework validation was conducted through a workshop involving the same stakeholders who participated in the case studies, in which the feedback on possible improvements to the framework was obtained. The framework demonstrated its practicality, clarity and appropriateness for use across the SDM projects.Significantly, this research has the potential to direct standardisation of design and process in construction projects in particular in the public sector and could help achieve a sustained project performance improvement in the Saudi construction industry.

As pontes de madeira com tabuleiro multicelular protendido são uma das mais recentes tecnologias usadas na construção das modernas pontes de madeira. Nesta tese é realizado o estudo teórico e experimental do comportamento estrutural destas pontes. Os principais métodos de cálculo são apresentados e discutidos. A investigação experimental foi realizada em dois modelos reduzidos em escala 1:3 com as mesmas dimensões externas mas diferente quantidade de nervuras. Os modelos foram ensaiados com diferentes posições de carregamento enquanto os deslocamentos, deformações e forças nas barras, eram monitorados. Os resultados obtidos demonstraram que os modelos de Placa Ortotrópica Equivalente e Elementos Finitos podem ser empregados para o dimensionamento das pontes de madeira com tabuleiro multicelular protendido. O método de Viga Equivalente pode ser empregado desde que utilizado o correto Fator de Distribuição de Carga. Os estudos realizados neste trabalho, indicam a viabilidade da utilização deste sistema estrutural para pontes com vãos de 12 a 25 m / Timber bridges with multicellular prestressed decks is one of the most recent technology for modern timber bridges construction. In this thesis the theoretical and experimental study of the structural behavior of these bridges is accomplished. The main calculation methods are introduced and discussed. Two reduced models on scale 1:3, with the same external dimensions but different number of webs, were used for the experimental investigation. The models were tested with different load positions meanwhile displacements, strains and bar forces were measured. The obtained results have show that either model of Equivalent Orthotropic Plate or Finite Elements can be used for the design of this type of bridge. The Equivalent Beam model can also be employed as long as the correct Load Distribution Factor is chosen. The accomplished studies demostrate that this structural system is viable for bridges with span from 12 to 25 m

Thesis (Ph.D.)--Pardee Rand Graduate School, 2009. / Title from PDF t.p. Includes bibliographical references.

Made available in DSpace on 2014-12-02T11:16:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-06-02Bitstream added on 2014-12-02T11:21:01Z : No. of bitstreams: 1 000797407.pdf: 25465836 bytes, checksum: 24d2d3f2b43664ad300e270ae84dae95 (MD5) / Nas metodologias de design observamos a importância dos protótipos. Porém, constatamos que a sua utilização é deixada para as fases finais do projeto, o que limita a avaliação do design. O termo protótipo tem sido usado para designar uma versão final do projeto. Contudo, podemos tratá-los de uma forma mais ampla como: uma aproximação do produto, dos sistema ou de seus componentes, o que permite classificá-los em baixa, média e alta fidelidade. Ao considerarmos os protótipos como artefatos mediadores de informação e comunicação, poderemso utilizá-lo como ferramenta de gestão de design. O gerenciamento e comparação das informações sobre a funcionalidade, usabilidade e estética das alternativas permitem realizar uma seleção mais precisa. O propósito do protótipo, os estágios de utilização e a emergência de novas tecnologias de prototipagem e manufatura virtual e rápida, favorecem sua maior utilização e permitiram a criação de uma nova metodologia de design. Essa auxiliará os designers no desenvolvimento dos projetos, através da escolha do protótipo mais adequado a cada área, fase, estágio e propósito de design. Nesse sentido, nessa pesquisa, construímos e validamos uma metodologia denominada: Metodologia de Design Mediada por protótipos. Metodologia essa que coloca o protótipo no centro do processo de Design criando um processo de design centrado nos protótipos / We have observed in the methodologies of the importance of design prototypes. However, we not that its use is left to the final stages of the project, which limit the design evaluation. The term prototype has been used to designate a final version of the project. However, we can treat them more widely as an approximation of the product, system or its components, which can be classified as low, medium and high fidelity. When we consider the prototype artifacts as mediators of information and communication, we use it as a design management tool. The management and comparison of information on the functionality, usability and aesthetcs of alternative perfom a more precise selection. The purpose of the prototype stages of use and the emergence of new technologies and virtual prototyping and rapid manufacturing, encourage their greater use and allowed the creation of a new design methodology. This will assist designers in the development of projects by choosing the most appropriate to each area, stage, stage design and purpose of the prototype. Accordingly, in this research, we constructed and validated a methodology called Design Methodology Mediated prototypes. methodology that puts this prototype in the center of the design process by creating a process-centered design in the prototypes