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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.
141

Sustainability Oriented Feasibility Model for Construction Decision Making: Water Recycling Cases in Buildings

Zhang, Yue 18 February 2010 (has links)
Traditionally, feasibility analysis in the construction sector is limited to financial considerations. As the concept of sustainability becomes increasingly important, the methods used in a feasibility analysis have to be reconfigured in a way that incorporates elements of sustainability. This research uses water recycling systems (within the built environment) as an example to demonstrate how sustainability factors can be integrated quantitatively in feasibility studies. The model is structured in a triple-bottom-line framework, which consists of economic, environmental, and social aspects. Each aspect is measured by a spectrum of parameters, which evaluate three project outcomes of water recycling systems—water savings, project requirements, and positive image. Based on the quantified parameters, Green Factor, a decision making method, is formulated to assist in sustainability oriented feasibility analysis for construction projects.
142

Supported Student Success| Communities of Practice in Higher Education

deChambeau, Aimee Lynn 18 September 2014 (has links)
<p> This research tells a story about how students form communities of practice that help them succeed in graduate school. Told within the context of individual and collective experiences, it holds valuable lessons for how student success can be supported across the higher education landscape. Communities of practice can develop spontaneously when individuals involved in a common activity or with a sense of shared identity come together to deal with organizational complexities or establish a forum for continued learning. The practice of becoming an accomplished and successful student who is able to develop scholarly abilities and deepen disciplinary understanding, experience personal growth and achievement, while at the same time maintaining a healthy school-work-life balance is a non-trivial exercise. Membership in a community of practice can help students achieve success as part of the process of navigating this complex journey. Generously informed by the experiences of Prescott College sustainability education doctoral students, this research used survey responses, anecdote circles, interviews, and grounded theory methods to determine how communities of practice develop among graduate students in support of their success. This presentation asks and answers questions about what communities of practice are, how and why they develop, and what value they can bring to higher education. </p><p> <i>Keywords</i>: student success, community of practice, graduate education, sustainability education, sustainable education, higher education </p>
143

The water footprint of urban energy systems| Concepts, methods and applications for assessing electricity supply risk factors

Cohen, Elliot J. 26 July 2014 (has links)
<p> This dissertation adds to the body of knowledge of the <i>water-energy nexus</i> in four measurable ways. First, a water withdrawal footprint of energy supply (WWFES) to cities was developed, and placed it in the context of other water footprints defined in the literature. The WWFES provides a novel way to quantify direct and indirect water requirements to satisfy urban energy demand. The magnitude of the WWFES for Denver, Colorado was found to be 381 liters/person/day and 66% as large as all direct water uses in the city combined (mean estimate). This finding is relevant to urban sustainability planning as it shows significant water conservation may be achieved through energy efficiency and energy conservation. </p><p> Next, we demonstrate the robustness of the WWFES method for a rapidly developing city (Delhi) with unique energy requirements, energy infrastructure and data availability compared to the initial test case (Denver). Data collected for the Indian power sector enabled exploration of spatial- and temporal-variability of electricity supply to cities and the associated dynamic WWFES. Integrating over both space and time for one year, we estimate the water requirements of electricity production alone to be 36% as large as municipal water supply for Delhi, compared to 16% for Denver. In both cases, this highlights that electricity supply, like municipal supply, can be at risk during drought or other hydrological extremes, corroborated by interviews with industry experts. </p><p> The third and fourth contributions of this dissertation are to place water-related constraints to power generation in the context of other system risks using both social science methods and data-driven statistical analysis. For the former, a survey was administered to electricity infrastructure operators serving Delhi with three objectives: (1) identify and rank system risks to power supply reliability based on industry perceptions of risk; (2) identify and rank current and future service provision priorities; and (3) collect social network data regarding interaction between infrastructure operators. For the latter, an empirical study of electricity supply reliability in Northern India was conducted in a hierarchical modeling framework to assess the contribution of structural, environmental and supply-chain constraints to grid reliability. Model results indicate the WWFES is a statistically significant predictor of power supply reliability in Northern India when we control for structural, climate and supply-chain covariates. These results highlight the importance of the WWFES when evaluating risks to, and reliability of, trans-boundary energy systems.</p>
144

Transformative Experiences with Nature| A Phenomenological Exploration

Caston, Daniel W. 08 August 2014 (has links)
<p> This dissertation presents findings from an exploratory, phenomenological study that examined the dynamics of transformative experiences with nature through three lenses: the state of being of a person in a state of deep play, the human affinity for nature, and the human capacity to experience transformation. Stories were collected from fifteen people via semi-structured interviews. Findings indicate that transformative experiences are comprised of five qualities that emerge as the moment unfolds. They are novelty, engagement, immersion, openness, and attunement. Our affinity for nature and our capacity for deep play foster the feelings and thoughts associated with each of these qualities. Other findings indicate that an experience does not occur in isolation but rather occurs in concert with other aspects of a person's life. Antecedents such as education, beliefs, and previous experiences influence how a person perceives of and interacts with an experience. The substantiation process influences how a person makes meaning of and integrates an event into her/his life. Significant moments with nature may influence a person's life in significant ways prompting changes in interests, careers, worldviews, and her/his relationship with nature. Findings demonstrate that the transformative experiences of the study participants shifted their engagement with nature toward a more nature oriented lifestyle. The findings of this study inform adventure education, outdoor and environmental education, transformational learning, and adult education. These finding also inform land development and management fields such as forestry, natural resource management, and urban planning and development.</p>
145

Development of Energy Models for Production Systems and Processes to Inform Environmentally Benign Decision-Making

Diaz-Elsayed, Nancy 08 August 2014 (has links)
<p> Between 2008 and 2035 global energy demand is expected to grow by 53%. While most industry-level analyses of manufacturing in the United States (U.S.) have traditionally focused on high energy consumers such as the petroleum, chemical, paper, primary metal, and food sectors, the remaining sectors account for the majority of establishments in the U.S. Specifically, of the establishments participating in the Energy Information Administration's Manufacturing Energy Consumption Survey in 2006, the non-energy intensive" sectors still consumed 4*10<sup>9</sup> GJ of energy, i.e., one-quarter of the energy consumed by the manufacturing sectors, which is enough to power 98 million homes for a year. The increasing use of renewable energy sources and the introduction of energy-efficient technologies in manufacturing operations support the advancement towards a cleaner future, but having a good understanding of how the systems and processes function can reduce the environmental burden even further. To facilitate this, methods are developed to model the energy of manufacturing across three hierarchical levels: production equipment, factory operations, and industry; these methods are used to accurately assess the current state and provide effective recommendations to further reduce energy consumption. </p><p> First, the energy consumption of production equipment is characterized to provide machine operators and product designers with viable methods to estimate the environmental impact of the manufacturing phase of a product. The energy model of production equipment is tested and found to have an average accuracy of 97% for a product requiring machining with a variable material removal rate profile. However, changing the use of production equipment alone will not result in an optimal solution since machines are part of a larger system. Which machines to use, how to schedule production runs while accounting for idle time, the design of the factory layout to facilitate production, and even the machining parameters &mdash; these decisions affect how much energy is utilized during production. Therefore, at the facility level a methodology is presented for implementing priority queuing while accounting for a high product mix in a discrete event simulation environment. A baseline case is presented and alternative factory designs are suggested, which lead to energy savings of approximately 9%. </p><p> At the industry level, the majority of energy consumption for manufacturing facilities is utilized for machine drive, process heating, and HVAC. Numerous studies have characterized the energy of manufacturing processes and HVAC equipment, but energy data is often limited for a facility in its entirety since manufacturing companies often lack the appropriate sensors to track it and are hesitant to release this information for confidentiality purposes. Without detailed information about the use of energy in manufacturing sites, the scope of factory studies cannot be adequately defined. Therefore, the breakdown of energy consumption of sectors with discrete production is presented, as well as a case study assessing the electrical energy consumption, greenhouse gas emissions, their associated costs, and labor costs for selected sites in the United States, Japan, Germany, China, and India. </p><p> By presenting energy models and assessments of production equipment, factory operations, and industry, this dissertation provides a comprehensive assessment of energy trends in manufacturing and recommends methods that can be used beyond these case studies and industries to reduce consumption and contribute to an energy-efficient future.</p>
146

Community gardening and nutritional health program for low-income youth affected by food scarcity| A grant proposal

Dosen, Melanie K. 13 August 2014 (has links)
<p> The purpose of this project was to locate a potential funding source and write a grant to fund a community garden and nutritional program for the Boys &amp; Girls Club of the Foothills in Monrovia, California. This program will provide gardening, nutrition, and cooking classes for at-risk youth who are from low income or ethnic minority neighborhoods. The program will also include community engagement projects in which program participants engage their community regarding healthy and food security issues. The proposed program is expected to have positive health and educational outcomes for at-risk youth, as well as raise awareness of food security issues in the community.</p><p> A search for potential funders was done using the Internet. The Opal<sup> &reg;</sup> apple Youth Make a Difference Initiative was identified as the best fit for the program. Actual submission of this grant was not requirement for successful completion of this project.</p>
147

The impact of moral values on ethical practices in environmental management

Younis, Khalid M. 12 August 2014 (has links)
<p> The Harbormaster Command and Control Center (HCCC) project provides mobile platforms intended to control harbor operations. The main component of the HCCC is a double-expandable shelter mounted on a 5 ton military flatbed truck. Kentucky Trailer Corporation manufactured a baseline shelter using standard materials (aluminum, steel, plywood, etc.) and also considered alternate designs using composite materials (carbon fiber laminates, glass fiber laminates, composite sandwich configurations, etc.).</p><p> Two faculty members and several graduate students in the Department of Mechanical Engineering at the University of Louisville participated in this effort, primarily in terms of material selection, structural analysis, and design approaches. This thesis presents one portion of that work. This consists of a finite element model (FEM) of the HCCC using standard materials. This model was constructed to match the design proposed and later built and delivered by Kentucky Trailer. The thesis also presents two structural analysis simulations performed using the HCCC FEM.</p><p> The HCCC FEM was built using ANSY Mechanical APDL. This software utilizes text-based &ldquo;input files&rdquo; to build, analyze and post-process the HCCC FEM entirely without user assistance. The author generated these input files to create the HCCC FEM structure using 3D beam elements, layered shell elements, and point mass elements. This approach represented a simplification to eliminate the need for more computationally intensive 3D solid elements; it also provides a simpler approach for changing the model as design changes occur. For example, the thickness of an aluminum plate in the HCCC FEM model is represented as a number that can be easily changed; for a 3D solid element model, revisions would involve changing solid model entities such as volumes and areas followed by remeshing. This is feasible in a small model but impractical in a large complex model such as the HCCC FEM.</p><p> The HCCC FEM is constructed in a modular manner, with different models representing the roof, sides, rear and front, floor and both expandable sections. These various submodels are joined together using constraint equations to cause identical displacements and rotations along common boundaries between models. This also permitted scenarios such as analysis with the expandables retracted or expanded. Contact elements are used to simulate support of the HCCC FEM along is bottom by a rigid boundary simulating the truck bed carrying the HCCC. The HCCC FEM is a nonlinear model due to both the contact elements and the ability to solve in cases of arbitrarily large displacement needed for dynamic analysis.</p><p> Two analyses using the HCCC FEM are presented. The first is a static analysis under various constant inertial (acceleration) loads to demonstrate that the structure is worthy for air transport using a C-17 aircraft. The second is a dynamic analysis simulating the structural response during a rail impact; this occurs when the HCCC is mounted on a rail car which then collides with another rail car. Both analyses were beneficial in demonstrating that the HCCC design performs sufficiently well in service.</p>
148

Transforming relationships| A qualitative analysis of westerners' experience of reciprocity with the natural world

Duphily, Monique 28 June 2014 (has links)
<p> This study responds to the call in the ecological literature (Berry 1988, 1999; Macy &amp; Brown, 1998; Spretnak, 2011) for cognitive, spiritual, and relational shifts in humanity's perception and experience of the natural world. It examines the lived experience of a diverse group of Western adults who were initiated into an eco-spiritual Andean indigenous tradition centered upon reciprocity. Andean reciprocity, or <i>ayni </i>, involves maintaining a relationship of mutual exchange with the natural world and implies a paradigm shift, from the dominant Western paradigm to one that views the Earth as animate and able to reciprocate. In this study, reciprocity is explored as a potential means for Westerners to facilitate living in harmony with the natural world. </p><p> This basic qualitative analysis used semi-structured interviews with 8 U.S. residents who were initiated into an eco-spiritual Andean indigenous tradition and report that they actively maintain reciprocity with the natural world three or more years after their initiation. Interviews solicited stories from participants and, in the process, honored the oral culture of the Q'ero, into which the coresearchers were initiated. Data analysis was an inductive process that extracted salient themes from all stories to construct a process of sacred reciprocity for Westerners. </p><p> This study can inform Westerners who are interested in deepening relationship and learning practical ways of being in harmony with the natural world. It can also inform anyone interested in developing skillful means to utilize ancestral teachings in a contemporary context. For Westerners and industrialized societies, these practices and tools could help facilitate ecological citizenry and cultural transformation.</p>
149

Integration of Axiomatic Design with Quality Function Deployment for Sustainable Modular Product Design

Hosseinpour, Arash 14 January 2014 (has links)
Design is one of the most important stages in product development. Product design has experienced significant changes from concentrating on cost and performance to combining economic, environmental and societal considerations in design process. Sustainability is a new concept to balance economic, social and environmental aspects in product design. This research focuses on sustainable product design. The main challenging problem in the sustainable design is how the sustainable criteria can be used as quantitative metrics to evaluate products. This research integrates Axiomatic Design and Quality Function Deployment (QFD) concepts with Eco-design tools, such as Life cycle Assessment (LCA), to establish the quantitative metrics for sustainable product design. A novel wheelchair is designed as a case study in this research. Modularity is conducted to improve the wheelchair for the end of life cycle management
150

An automated solution to facilitate sustainable DSM in the mining environment / J.P. Steyl

Steyl, Jacob Petrus January 2008 (has links)
South Africa is experiencing a serious electricity supply problem. This problem is expected to persist until at least 2012. During the winter of 2006 load shedding and electricity supply-cuts started occurring in the Western Cape. These spread to the rest of the country during the summer of 2007. By January 2008 daily load shedding was a common occurrence across South Africa. In the 1990s the Department of Minerals and Energy (DME), the National Energy Regulator of South Africa (NERSA) and Eskom started a national demand side management (DSM) programme with the help of energy services companies (ESCOs). The aim is to reduce demand peaks and to promote the efficient use of electricity. These projects can be implemented much faster than building new power stations and are also more cost-effective. In 2008 an accelerated DSM program was launched to address the electricity shortage in South Africa. Unfortunately, South African DSM projects experience the same sustainability problems as their counterparts overseas. These projects have been shown to be unsustainable over the five year projected life-span. There are various reasons for this, including client mismanagement and maintenance problems. An automated and rapid feedback system was identified as the best solution to address this problem. If plant personnel could be informed as soon as a DSM project's performance starts to decline, they would be able to respond much faster to rectify the problem. Reporting on DSM performance is difficult to achieve as these reports and the processing of measured data are time-consuming and presently no system exists to automate the process. A new feedback solution was developed to fully automate the process of data gathering, processing and reporting. The implemented solution reduced the number of man-hours spent by ESCOs' project engineers dramatically. In addition, project performance increased by 13% and showed an increase in over-performance of 12.8%, while financial savings for clients improved by an average of 12%. The feedback solution also provides the client with an accurate maintenance reporting system. This system can be implemented on all DSM projects, maximising Eskom's DSM investment. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2009.

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