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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.
31

Development of a conceptual model for ash dump system using hydraulic and tracer test techniques

October, Adolf Gerswin January 2011 (has links)
<p>Coal provides for 77% of South Africa&rsquo / s primary energy needs and is therefore a major resource that supports the socio-economic needs of South African citizens. Power stations are the major consumers of coal in South Africa and produces electricity from burned coal. The burning of coal produces a large volume of ash that is disposed in the form of ash dump systems. The ash&nbsp / dump system is treated with high salinity process water from the power station for dust suppression. The process water contains salts due to evaporation processes from the recirculation&nbsp / &nbsp / of&nbsp / water in the cooling water system. Various studies to evaluate the sustainability of the ash dump system as a sustainable salt sink were therefore conducted. This study aimed to develop a conceptual model for the ash dump system by evaluating the movement of the process water trough the ash dump and the impacts it might have on the underlying weathered dolerite aquifer. This was achieved by evaluating the hydraulic and transport properties of the ash dump system. An initial site conceptual model was first established prior to the application of the hydraulic&nbsp / and transport methods. The initial conceptual model was based on the literature, previous reports and an initial site walk over. Known and tested hydraulic and transport methods were applied&nbsp / n bo.th field and laboratory scale for the saturated part of the ash dump system. The laboratory experiments comprised of column and core experiments. These methods assisted in&nbsp / parameter estimation of hydraulic and transport properties and also assisted in the planning of the field experiments. The field experiments were conducted in the form of slug tests, tracer&nbsp / dilution and natural gradient divergent tracer test experiments. The combined laboratory and field experiments provided statistically significant values that were then used as inputs into the&nbsp / conceptual model. Field experiments were also applied to a surrogate aquifer that represented the underlying shallow weathered dolerite aquifer of the ash dump system. The components of&nbsp / the updated conceptual model identified and investigated include the physical environment, the calculated hydraulic and transport properties.The ash dump can be conceptualized as a 20 to&nbsp / &nbsp / 30 meter high heap of consolidated clay size ash&nbsp / particles built on top of an underlying shallow weathered dolerite aquifer. The ash dup is directly connected to the underlying weathered&nbsp / dolerite aquifer. The saline water within the saturated zone has the ability to move through the ash dump system with hydraulic conductivities ranging between 10-1-10- 2 m/day, with flow&nbsp / velocities of 7-8m/day and effective porosities of 1%-2%. The hydraulic properties of the ash dump are, amongst others, controlled by the ash geology, contact time of the process water with the&nbsp / sh and show a significant reduction in hydraulic conductivity over time, before reaching a steady state. The transport properties are controlled by advection and spreading in available&nbsp / pathways. Results for the surrogate underlying fractured rock aquifer show flow velocities of 31m/day and an effective porosity of 1%.This suggests that the underlying weathered dolerite&nbsp / aquifer is vulnerable to process water contamination from the ash dump system. The study illustrates the importance of a site conceptual model before the application of investigative&nbsp / methods. Hence having a site conceptual model provides an excellent platform for hydraulic and transport estimation. The development of a site conceptual model enhanced the&nbsp / understanding of flow and transport movement of the processed&nbsp / water trough the ash dump, it also assisted as a beneficial tool to enhance ash dump management.</p>
32

Katalogen som tolkningsredskap : Bibliografiska relationer i Resource Description and Access (RDA), med särskild hänsyn till operationaliseringsproblem / The Catalog as Interpretative Tool : Bibliographic Relationships in Resource Description and Access (RDA), with Special Regard to Problems of Operationalization

Wallheim, Henrik January 2013 (has links)
The new cataloging code Resource Description and Access (RDA) provides a system of instructions for recording relationships between related resources by means of a controlled vocabulary of relationship designators. The purpose of this two years master’s thesis in Archive, Library and Museum studies is to examine the construction of this system, as well as its theoretical foundation. One theoretical point of departure is the necessity of operational definitions for consistent identification of bibliographic relationships. Another such point of departure is that the theoretical model on which RDA is based (the FRBR model) is not a complete description of the biblio­graphic universe, but merely a limited representation of a set of assumptions about that universe. The thesis first examines Barbara B. Tillett's and Richard P. Smiraglia's theories and taxonomies of bibliographic relationships. The analysis shows that, in spite of their claims to provide a theoretical basis for consistent treatment of bibliographic relationships, neither Tillett nor Smiraglia offers operationally applicable definitions. The thesis then turns to RDA in order to examine the instructions and the list of relationship designators. After an introductory survey of RDA chapters 24 to 28, the possibility to record relationship designators at different entity levels is discussed. Remarkably, RDA neither provides instructions for how to choose between the entity levels, nor does it point out what this choice signifies. Finally, a selection of relationship designators representing content relationships is examined. The selected designators are analysed and compared to corresponding categories in literary theorist Gérard Genette's attempt to classify intertextual relationships. The analysis shows that though some of the selected designators are satisfactorily operationalized, most are not.
33

A Study on the Service Quality on the Blockbuster, Jointly Held by the Taiwan Print Media and Museum -A Case-study of Da Vinci Travelling Exhibition

Chang, Kai-yao 16 August 2010 (has links)
Taiwan public museums and print medias hold many ¡§blockbusters¡¨ one after another since 1990. This trend started from US then spread to all over the world. The considerable amount of visitors not only solved the financial problem, but also built the field for print media chasing the cultural capital and developing new business model. We can generalize this trend to three concepts, first, Issues of the Administrative Corporation of National Museum, second, the trend of museum marketing, third, new museology. Those concepts break the ossified museum organization system and the icy impression. However, a stream of people and money will bring some doubts, such like exhibition quality goes down, over commercialize, and unprofessional. Most of exhibition assessments about museum are overall assessments which include a wide range. But it's not applicable to blockbuster that happens only once, tours around, and needs inter-organizational cooperation. This study is a case study of ¡§Da Vinci Travelling Exhibition¡¨ which is held by United Daily News Group, National Chiang Kai-shek Memorial Hall, and National Science and Technology Museum. The research design in this study is based on ¡§Conceptual Model of Service Quality¡¨ and ¡§Extended Model of Service Quality¡¨ which was brought out by Parasuraman, Zeithmal, & Berry. This study counts out the coefficients which existed in the service quality gap theory, then, establish regression. With the regression, we can judge which service gap character will effect customer¡¦s satisfaction of service quality. So that we can point out the way how to improve blockbuster's service quality and build an exhibition assessment driving from customer. This study also investigated the relation among demographic variables and customer¡¦s satisfaction of exhibition service quality. Three findings are revealed. First, demographic variables have significant effect on customer¡¦s attitude toward blockbuster service quality. Second, except for gap character 1(managerial perception), gap character 2(managerial standard)¡Bgap character 3(service performance) and gap character 4(external communication) has a function relationship to the gap 5 was confirmed. Third, Use service gap theory to establish an exhibition service quality assessment is possible.
34

A Verification Approach For Dynamics Of Metamodel Based Conceptual Models Of The Mission Space

Eryilmaz, Utkan 01 June 2011 (has links) (PDF)
Conceptual models were introduced in the simulation world in order to describe the problem domain in detail before any implementation is attempted. One of the recent approaches for conceptual modeling of the military mission space is the KAMA approach which provides a process description, a UML based notation, and a supporting tool for developing conceptual models. The prominence of the approach stems from availability of guidance and applications in real life case studies. Although the credibility of a conceptual model can be leveraged through use of a structured notation and tools, the verification and validation activities must be performed to arrive at more credible conceptual models. A conceptual model includes two categories of information: static and dynamic. The dynamic information describes the changes that occur over time. In this study, the dynamic characteristics of the conceptual models described in KAMA notation are explored and a verification approach based on these is proposed. The dynamical aspects of KAMA notation and example conceptual models provide the necessary information for characterization of the dynamical properties of conceptual models. Using these characteristics as a basis, an approach is formulated that consists of formal and semiformal techniques as well as supporting tools. For description of additional properties for dynamic verification, an extended form of KAMA is developed, called the KAMA-DV notation. The approach is applied on two different real-life case studies and its effectiveness is compared with earlier verification studies.
35

Transforming Conceptual Models Of The Mission Space Into Simulation Space Models

Kucukyavuz, Fatih 01 April 2011 (has links) (PDF)
Helping to abstract a valid model from real system, conceptual modeling is an essential phase in simulation development lifecycle. With the development of the KAMA framework, a new methodology was presented to develop mission space conceptual model for simulation systems. It provides metamodel elements represented by graphical diagrams to develop conceptual models of mission space. BOM (Base Object Model), developed by SISO (Simulation Interoperability Standards Organization), is another conceptual modeling concept serving for simulation space. KAMA models are very close to problem domain and intend to model real world concepts in requirement analysis and development phase. Whereas, being vital inputs for the simulation design phase, BOM models are closer to solution domain. Hence there is no defined way of using the captured mission space knowledge in simulation space, problem arises when moving from requirement analysis to design phase. In this study, to solve this problem, we propose a method for transforming mission space conceptual models in simulation space. Our solution approach will be mapping the KAMA mission space models to BOM simulation space models for automatically transport real world analysis results to simulation designers.
36

Understanding the Designing of Knowledge Work Support Tools as a Situated Practice / Erfarenhetsbaserat lärande perspektiv på design av IT-stöd för kunskapsarbete

Eberhagen, Niclas January 2011 (has links)
The aim of the thesis is twofold. First, a need is exposed for adopting a situated design perspective in designing computer-based tools that support knowledge work. Second, an examination is made of what this perspective may reveal concerning the nature of processes and relations within the design situation. This is done to understand better what it means for users and developers, as well as other stakeholders, to approach and capture the tacit knowing within the work context. The argument for adopting a situated design perspective is based on experience drawn from development projects, as well as literature reviews. In these projects, the design situations encountered are best characterized as explorative and iteratively interpreted. Here, approaching and understanding the work context, together with the users, has at best been a pursuit of the vision of the future system guided by local circumstances, and where the users had difficulties in expressing and understanding what it is they want and how they want it. This implies that formal engineering methods, where the development work is reduced to an engineering endeavor based on a rationalistic perspective, are not sufficient. The situated design perspective is presented in this thesis as a conceptual model of the design practice, highlighting its constituent worlds, processes, and relations. The model depicts designing as an explorative and sense-making process, navigating between what is wanted or envisioned and what may be negotiated and discovered. It emphasizes the importance of the artifact being designed as a means to capture, communicate, and discover what is possible in the work context. The model makes clear that the design process is highly situated, and that it cannot take place outside the work context because of interdependent relationships. It is designing within the living work context, not design for an objectified one. Thus, it cannot be planned as a pure engineering endeavor, but needs to be viewed as a situated practice.
37

Groundwater recharge, flow and discharge in a large crystalline watershed

GLEESON, THOMAS 14 July 2009 (has links)
The objective of this thesis is to constrain the fundamental hydrogeological processes of a large crystalline fractured rock watershed in the Canadian Shield. The fundamental hydrogeological processes of groundwater recharge, flow and discharge are examined individually as well as holistically using a revised conceptual model. The study area is the topographically-subdued Tay River watershed in eastern Ontario where a thin veneer of soil overlies Precambrian crystalline rocks and Paleozoic sediments. Spatial scales from local-scale (100s m2 to 1 km2) to watershed-scale (>100 km2) are examined. Recharge processes are defined using hydrogeological characterization, numerical simulation and isotopic, thermal and hydraulic responses to a snowmelt event. Soil thickness and bedrock transmissivity are highly heterogeneous at the local scale. Cold, 2H depleted snowmelt locally recharged the bedrock aquifer to depths of at least 20 m within two days. This rapid recharge process is localized to areas where the soil is very thin whereas slow recharge is likely widespread. The impact of lineaments on groundwater flow at the watershed-scale is examined using geomatic analysis, hydrogeological characterization, numerical simulation and fracture mapping. Lineaments are interpreted as structural features because the two principal lineament sets are oriented parallel to fracture and fault orientations. The fractured bedrock underlying lineaments generally consists of poorly connected zones of reduced permeability suggesting lineament can be barriers to recharge and flow in this setting. Natural conservative, radioactive, and thermal tracers are integrated with streamflow measurements and a steady-state advective model to delimit the discharge locations and quantify the discharge flux to lakes, wetlands, creeks and the Tay River. The groundwater discharge rate to most surface water bodies is low. Groundwater discharge is distributed across the watershed rather than localized around lineaments or zones of exposed brittle fractures. In the revised conceptual model, recharge is considered two separate processes, groundwater flow is compartmentalized and the discharge flux is considerably lower than porous media watersheds. This thesis provides a better understanding of fundamental hydrogeological processes in a large crystalline fractured rock watershed which impacts the sustainability of water resources and ecology. / Thesis (Ph.D, Civil Engineering) -- Queen's University, 2009-07-13 14:51:25.244
38

Development of a conceptual model for ash dump system using hydraulic and tracer test techniques

October, Adolf Gerswin January 2011 (has links)
<p>Coal provides for 77% of South Africa&rsquo / s primary energy needs and is therefore a major resource that supports the socio-economic needs of South African citizens. Power stations are the major consumers of coal in South Africa and produces electricity from burned coal. The burning of coal produces a large volume of ash that is disposed in the form of ash dump systems. The ash&nbsp / dump system is treated with high salinity process water from the power station for dust suppression. The process water contains salts due to evaporation processes from the recirculation&nbsp / &nbsp / of&nbsp / water in the cooling water system. Various studies to evaluate the sustainability of the ash dump system as a sustainable salt sink were therefore conducted. This study aimed to develop a conceptual model for the ash dump system by evaluating the movement of the process water trough the ash dump and the impacts it might have on the underlying weathered dolerite aquifer. This was achieved by evaluating the hydraulic and transport properties of the ash dump system. An initial site conceptual model was first established prior to the application of the hydraulic&nbsp / and transport methods. The initial conceptual model was based on the literature, previous reports and an initial site walk over. Known and tested hydraulic and transport methods were applied&nbsp / n bo.th field and laboratory scale for the saturated part of the ash dump system. The laboratory experiments comprised of column and core experiments. These methods assisted in&nbsp / parameter estimation of hydraulic and transport properties and also assisted in the planning of the field experiments. The field experiments were conducted in the form of slug tests, tracer&nbsp / dilution and natural gradient divergent tracer test experiments. The combined laboratory and field experiments provided statistically significant values that were then used as inputs into the&nbsp / conceptual model. Field experiments were also applied to a surrogate aquifer that represented the underlying shallow weathered dolerite aquifer of the ash dump system. The components of&nbsp / the updated conceptual model identified and investigated include the physical environment, the calculated hydraulic and transport properties.The ash dump can be conceptualized as a 20 to&nbsp / &nbsp / 30 meter high heap of consolidated clay size ash&nbsp / particles built on top of an underlying shallow weathered dolerite aquifer. The ash dup is directly connected to the underlying weathered&nbsp / dolerite aquifer. The saline water within the saturated zone has the ability to move through the ash dump system with hydraulic conductivities ranging between 10-1-10- 2 m/day, with flow&nbsp / velocities of 7-8m/day and effective porosities of 1%-2%. The hydraulic properties of the ash dump are, amongst others, controlled by the ash geology, contact time of the process water with the&nbsp / sh and show a significant reduction in hydraulic conductivity over time, before reaching a steady state. The transport properties are controlled by advection and spreading in available&nbsp / pathways. Results for the surrogate underlying fractured rock aquifer show flow velocities of 31m/day and an effective porosity of 1%.This suggests that the underlying weathered dolerite&nbsp / aquifer is vulnerable to process water contamination from the ash dump system. The study illustrates the importance of a site conceptual model before the application of investigative&nbsp / methods. Hence having a site conceptual model provides an excellent platform for hydraulic and transport estimation. The development of a site conceptual model enhanced the&nbsp / understanding of flow and transport movement of the processed&nbsp / water trough the ash dump, it also assisted as a beneficial tool to enhance ash dump management.</p>
39

New conceptual model for design development of smart clothing

Ariyatum, Busayawan January 2005 (has links)
Smart Clothing, the convergent future of the electronics and clothing industries, struggles to reach its true potential and enter the mass market because of 1) imbalanced contributions from the electronics and clothing sectors, 2) the lack of an integrated approach to optimise the input from the different areas, and 3) the unclear direction of the products. There is a need for an NPD process that balances all contributions and addresses new values based on user requirements. Moreover, a strategic approach, that challenges the development teams to go beyond their existing creative boundary and reconciles their differences, is required. According to the research, Smart Clothes should take the design approach of functional clothing and focus on the area of sportswear, personal healthcare and physical monitoring, as they fit the users’ lifestyle and requirements. Since social acceptance is an important factor, Smart Clothes must also have a good design and whilst, at the same time, perform all the basic functions that ordinary garments do. They should allow the user to personalise the styles and functions according to the benefits, with respect to product lifecycle and disassembly. A conceptual model of the NPD process was developed and tested with experts in this field. The proposed model provides the basis for a computer software to plan and manage product development teams and activities at the front-end of the NPD process. It offers several advantages: 1. Combining the NPD models and those of collaborative development 2. Providing a holistic view of Smart Clothing development 3. Clarifying of the roles of all participants within the collaborative development teams 4. Describing the responsibilities and expected contributions of all participants 5. Explaining working relationships and overlapping roles and responsibilities 6. Offering the directions for the creative boundary extension
40

Hidrogeologia e hidroquímica do Sistema Aqüífero Guarani na porção ocidental da bacia sedimentar do Paraná /

Gastmans, Didier. January 2007 (has links)
Resumo: O fluxo das águas subterrâneas no SAG, em sua porção ocidental, é caracterizado pela existência de três áreas de recarga regional, localizadas em Mato Grosso do Sul e Goiás. A partir destas áreas de recarga o fluxo regional é radial direcionado para o centro da Bacia do Paraná. Em algumas porções das zonas de aforamento ocorrem fluxos localizados de descarga. As águas apresentam características químicas que permitem sua classificação em: bicarbonatadas cálcicas ou calco-magnesianas, bicarbonatadas sódicas e bicarbonatadas cloretadas/sulfatadas sódicas, representando, nesta ordem, a sua evolução hidroquímica. Os mecanismos envolvidos nesta evolução são: dissolução de feldspatos e remoção do cimento carbonático do arcabouço mineral dos arenitos, seguido por troca iônica, responsável pelo aumento nas concentrações de sódio e diminuição nas concentrações de cálcio e, finalmente, o enriquecimento em cloreto e sulfato, oriundos dos aqüíferos sotopostos ao SAG. Foram reconhecidas três unidades hidroestratigráficas distintas no SAG: superior, representada pelos arenitos eólicos limpos, da Formação Botucatu, intenuediária, representada por arenitos finos e argilosos, e inferior, por arenitos finos, pouco argilosos, estas duas últimas unidades pertencentes à Formação Pirambóia. / The groundwater flow pattern in the occidental portion of SAG (Guarani Aquifer System) is characterized by the existence of three regional recharge areas located in Mato Grosso do Sul and Goiás states. From these areas ofrecharge the regional flow is radial and directed toward the center of Paraná Sedimentary Basin. Local discharge flows occurs in portions of outcrop regions. The groundwater can be classified as calcium or calcium-magnesium bicarbonate type, sodium bicarbonate type and sodium bicarbonate/chloride/sulphate type, representing in this sequence its hydrochemical evolution. The mechanisms responsible for this evolution are dissolution of feldspars and remova! of the carbonate cement of the sandstones mineral framework, followed by ionic exchange, responsible for the increase in the sodium concentration and decrease of calcium, and, finally, the enrichment in chloride and sulphate derived from underlying aquifers units. Three distinct hydrostratigraphics units in the SAG have been recognized: the upper unit is represented by aeolian sandstones from Botucatu Formation, the intermediate, represented by the fine and argillaceous sandstones, and the lower unit is constituted by fine sandstones with low content in clays, these last two units belong to the Pirambóia formation. / Orientador: Chang Hung Kiang / Coorientador: Ian Hutcheon / Banca: Osmar Sineli / Banca: Ricardo César Aoki Hirata / Banca: Alexandre Campane Vidal / Banca: Ernani Francisco da Rosa Filho / Doutor

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