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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.
101

The Influence of Child Sexual Abuse on Later Parenting Outcomes

Unknown Date (has links)
The purpose of this study was to investigate the relationship between child sexual abuse and high-risk maternal parenting indicators and the extent to which maternal depression and self-perceived parenting competence influence that relationship. Symbolic interactionism was the theoretical framework guiding this study from the Parenting Among Women Sexually Abused in Childhood dataset (1998). Path Analysis using AMOS (Arbukle, 1997) software was used to examine the hypotheses. Results indicate no direct relationship between CSA and parenting outcomes, parenting stress, or maltreatment behavior. Yet, the mediation variables, maternal depression and parenting sense of competence, were significantly associated with both CSA and the outcome variables. Post hoc analysis indicated that CSA was significantly associated with decreased parenting sense of competence, controlling for level of depression. These results highlight that the pathways for increased risk in parenting outcomes for CSA survivors are indirect and associated with beliefs of survivors' sense of competence and beliefs associated with depression, as opposed to any direct association with the sexual abuse itself. Implications for researchers and practitioners are discussed. / A Dissertation submitted to the Department of Family and Child Sciences in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Summer Semester, 2010. / May 10, 2010. / Child Sexual Abuse, Sexual Abuse, Parenting, Maltreatment / Includes bibliographical references. / Lenore McWey, Professor Directing Dissertation; Joyce Carbonell, University Representative; Tom Cornille, Committee Member; Ann Mullis, Committee Member.
102

Racial Discrimination and Alcohol Outcomes in Black Youth: A Person-Centered Approach

Unknown Date (has links)
Stress predicts alcohol use but less is known about the role of racial discrimination, a chronic and ubiquitous stressor, as a risk factor for underage drinking among Black youth. While most studies examine race/ethnic differences when exploring underage drinking outcomes, there is a need to understand within-group differences on the stress-alcohol use link in order to focus alcohol prevention and intervention efforts. Thus, this study sought to identify homogeneous subgroups of Black youth based on their experiences of racial discrimination by their teachers and peers in middle and high-school and assess whether these subgroups differed on alcohol-related outcomes in emerging adulthood. Latent transition analyses (LTA) was performed on racial discrimination indicators derived while youth were in the 8th and 11th grade. Findings demonstrated 3 distinct subgroups of youth. Youth in the Teacher-Peer Perceived Racial Discrimination (PRD) group were characterized as having high probabilities of experiencing racial discrimination from both teachers and peers. Those in the Teacher PRD group had high probabilities of experiencing racial discrimination from teachers and a low probability of experiencing racial discrimination from their peers. Finally, youth in the No PRD group had low probabilities across all racial discrimination indicators. Males were more likely to be in the Teacher-Peer and Teacher PRD groups compared to females. Youth in the Teacher-Peer PRD group consumed significantly more alcohol than the other groups, whereas, the Teacher PRD group experienced significantly more alcohol-related consequences. Parents' strategies on how to deal with racial discrimination were not significant protective factors for youth within any group. Implications of the study suggest the need to reduce race-based stress within the school context as a form of intervention and prevention of underage drinking among Blacks. / A Dissertation submitted to the Department of Family and Child Sciences in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Summer Semester, 2014. / June 20, 2014. / African American/Black, Alcohol, Latent Transition Analyses, Racial Discrimination / Includes bibliographical references. / Frank Fincham, Professor Directing Dissertation; John Taylor, University Representative; Kendal Holtrop, Committee Member; Ming Cui, Committee Member.
103

Life Cycle Thinking in Environmentally Preferable Procurement

Hochschorner, Elisabeth January 2008 (has links)
Products generate environmental impacts during their life cycle by consuming raw materials and energy, releasing emissions and producing waste. A procurement organisation can be a considerable driving force for more environmentally friendly products e.g. by requiring that products meet certain environmental criteria. The scope for environmental consideration when procuring materiel can be limited by lack of reliable information about the environmental characteristics of the product or service. Different types of tools (e.g. eco-labels, guidelines, checklists and tools for environmental assessment) can contribute some knowledge and help identify environmentally preferable products. This thesis focuses on use of tools for environmental consideration in Swedish defence acquisition but the results are also relevant for other organisations, since the procurement process analysed is rather general and the legal requirements are similar for other public organisations in Europe. A Swedish government decision in 1998 requires the Swedish Armed Forces (SAF) and Defence Materiel Administration (FMV) to take environmental consideration in all phases of the acquisition process. The importance of a life cycle perspective is stressed in several SAF and FMV environmental documents. The starting point of this thesis was that environmental consideration should be taken in the Swedish acquisition of defence materiel, considering the whole life cycle of products, with the aim of formulating proposals on environmentally friendly procurement. Some Ecodesign tools were reviewed and evaluated, two methods for simplified Life Cycle Assessment (LCA) were compared, tools and methodology were recommended, and used to study military materiel, and environmental Life Cycle Costing (LCC) was examined. In environmental work lacking a life cycle perspective, the most significant aspects risk being overlooked. Use of quantitative and/or simplified LCAs and inclusion of environmental costs in LCC are therefore recommended. LCA proved an appropriate tool for involving environmental consideration in the acquisition process, since it focuses on products and their life cycle. The MECO method proved best for simplified LCA. These suggested methods were evaluated by interviews with actors in the acquisition process. Four areas for LCA use in acquisition were identified: learning about environmental aspects of products; fulfilling customer requirements; setting environmental requirements; and choosing between alternatives. The interviewees were interested in using LCA, but there is a need for an initiative by one or several actors if the method is to be used regularly and the results must be communicated within the organisations involved in procurement. Environmental consideration should be taken early in the acquisition process and environmental matters integrated into other activities of the organisations involved. Environmental costs are not explicitly considered in the LCCs used by the interviewees today, but internal environmental costs should be included. Costs likely to be internal can also be included. / QC 20100616
104

Life cycle sustainability assessment of alternative green roofs – A systematic literature review

Tighnavard Balasbaneh, A., Sher, W., Madun, A., Ashour, Ashraf 21 November 2023 (has links)
Yes / There is general agreement on the importance of green roofs as ways of reducing GHG emissions, reducing overall costs and improving sustainability in urban areas. This systematic literature review highlights life cycle sustainability assessment as an essential criterion to evaluate green roofs. A bibliometric analysis was used to quantitatively review relevant literature. The Scopus database was chosen as a bibliographic database of academic publications. Thes period of search started from 2003 and final search was conducted on February 15, 2023. Based on further in-depth reading, 88 publication records which met the selection criteria, including 74 papers and 14 conference papers. Researchers from the United States contributed almost 31 % of the documents. We evaluated leading studies in this field and discussed assessment method, system boundaries and research gaps through a critical literature review and a systematic search review. Finally, we propose a framework and identify a gap and future research. The environmental aspect of green roofs have received more attention than economic issues. We found that most economic evaluations of green roofs are limited to their construction stage. As yet there is no comprehensive social study on green roofs. We considered a unified study of the economic, environmental impact and social evaluation of green roofs to be warranted. Additionally, various measurement methods should be used to assess the economic profitability of green roofs over the long term. In summary, this study provides a deeper understanding of the environmental, social, and economic performance of green roofs and identifies research gaps as well as future research directions.
105

Life cycle sustainability assessment of alternative green roofs – A systematic literature review

Balasbaneh, A.T., Sher, W., Madun, A., Ashour, Ashraf 21 November 2023 (has links)
Yes / There is general agreement on the importance of green roofs as ways of reducing GHG emissions, reducing overall costs and improving sustainability in urban areas. This systematic literature review highlights life cycle sustainability assessment as an essential criterion to evaluate green roofs. A bibliometric analysis was used to quantitatively review relevant literature. The Scopus database was chosen as a bibliographic database of academic publications. Thes period of search started from 2003 and final search was conducted on February 15, 2023. Based on further in-depth reading, 88 publication records which met the selection criteria, including 74 papers and 14 conference papers. Researchers from the United States contributed almost 31 % of the documents. We evaluated leading studies in this field and discussed assessment method, system boundaries and research gaps through a critical literature review and a systematic search review. Finally, we propose a framework and identify a gap and future research. The environmental aspect of green roofs have received more attention than economic issues. We found that most economic evaluations of green roofs are limited to their construction stage. As yet there is no comprehensive social study on green roofs. We considered a unified study of the economic, environmental impact and social evaluation of green roofs to be warranted. Additionally, various measurement methods should be used to assess the economic profitability of green roofs over the long term. In summary, this study provides a deeper understanding of the environmental, social, and economic performance of green roofs and identifies research gaps as well as future research directions.
106

Framework for sustainability assessment of industrial processes with multi-scale technology at design level: microcapsules production process

Navarro Rosa, Jennifer 28 May 2009 (has links)
In a world with limited resources and serious environmental, social and economical impacts, a more sustainable life style is everyday more important. Therefore, the general objective of this work is to develop a methodological procedure for eco-efficiency and sustainability assessment of industrial processes with multi-scale technology at design level. The methodology developed follows the ISO 14040 series for environmental LCA standard. To integrate the three pillars of sustainability the analytical hierarchical process was used. The results are represented in a triple bottom line framework. The methodology was applied to the case study "production of perfume-containing microcapsules" and different scenarios were assessed and compared. Several sustainability indicators were chosen to analyze the impacts. The results showed that this methodology can be used as a decision making tool for sustainability reporting. It can be applied to any process choosing in each case the corresponding set of inventory data and sustainability impact indicators. / En un mundo con recursos limitados y graves impactos ambientales, sociales y económicos, un estilo de vida más sostenible es cada día más importante. Debido a esto, el objetivo general de este trabajo es desarrollar un procedimiento metodológico para evaluar eco-eficiencia y sostenibilidad de procesos industriales con tecnología multi-escala a nivel de diseño. La metodología desarrollada sigue la serie ISO 14040 para el medio ambiente. Se utilizó el proceso analítico jerárquico para integrar los tres pilares de sostenibilidad. Los resultados se presentan en un balance triple. La metodología se aplicó al caso de estudio "producción de micro-cápsulas que contienen perfume" y se analizaron y compararon diferentes escenarios. Se seleccionaron diversos indicadores de sostenibilidad para analizar los impactos. Los resultados demostraron que esta metodología puede ser utilizada como herramienta de toma de decisiones y que puede aplicarse a cualquier proceso seleccionando, en cada caso, los datos del inventario y los indicadores.
107

Environmental Life Cycle Costing (ELCC) für Produkte der Solarenergie

Krause, Marcus 17 April 2013 (has links) (PDF)
Vor dem Hintergrund der zukünftigen Notwendigkeit einer nachhaltigen Energieversorgung beschäftigt sich die vorliegende Arbeit mit Technologien der regenerativen Energiequelle Solarenergie, insbesondere Photovoltaik (PV). Systeme zur Nutzung der unerschöpflich verfügbaren, sauberen und im Prinzip “frei Haus” gelieferten Energie der Sonne können eine bedeutsame Rolle in einer umweltverträglicheren Zukunft spielen. Allerdings ist die Herstellung der erforderlichen Komponenten heute i.d.R. noch energie- und kostenintensiv, weshalb für eine korrekte Bewertung dieser Technologien der gesamte Lebenszyklus betrachtet werden muss. Zur tieferen Analyse der PV wird die Methodik des Environmental Life Cycle Costing (ELCC) auf der Grundlage von drei Grundideen eingeführt. Konkret sind dies die Ausgangspunkte: Nachhaltigkeit, Lebenszyklusdenken und die Drei-Dimensionalität dieses Instrumentes durch die gemeinsame Betrachtung ökologischer, ökonomischer und technischer Aspekte in ihrem Zusammenspiel. Ausgehend von theoretischen Elementen der Ökobilanzierung (Life Cycle Assessment) und des Life Cycle Costings, verbunden mit den technischen Eigenschaften der Photovoltaik werden wichtigste Anforderungen und Schritte für die Durchführung eines ELCC für PV beschrieben. Mittels einer softwaregestützten Inhaltsanalyse wird im Anschluss der definierte Rahmen für ein ELCC für PV getestet (und modifiziert) gegen eine Auswahl von 135 bereits existierender Studien, die sich mit dem Lebenszyklus von PV-Technologien aus ökologischer und ökonomischer Sicht beschäftigen. Im Ergebnis hieraus können die wichtigsten Elemente eines ELCC für PV, wie beispielsweise ökologische Wirkungskategorien oder ökonomische Indikatoren, identifiziert werden (methodisches Feedback). In einem nächsten Schritt werden die Studien hinsichtlich ihrer “Qualität” bezogen auf ökologische, ökonomische und übergreifende Inhalte eines ELCC für PV bewertet. Auf diese Weise kann ein Inventar von Lebenszyklusanalysen für PV erstellt werden, das nach den Technologien und der inhaltlichen Qualität bezüglich eines ELCC strukturiert ist und für weitere Analysen als Grundlage dienen kann. Aus den bisherigen Ergebissen kann eine erste Einschätzung zum aktuellen Stand des ELCC für PV in der Literatur vorgenommen werden: Es existiert bereits ein großer Pool von Studien, die sich mit dem Lebenszyklus der PV beschäftigen. Mit Blick auf die Anforderungen eines ELCC für PV besteht jedoch Nachholbedarf in der Verbindung und gemeinsamen Betrachtung von hot spots und trade offs aus ökologischer und ökonomischer Perspektive. Der definierte theoretische Rahmen für ein ELCC für PV, die kodierten Studien sowie das erstellte Inventar von Lebenszyklusanalysen der PV können nun als Grundlage für weitere Analysen dienen. Insbesondere eine inhaltliche Auswertung der konkreten Ergebnisse von Studien kann so einen Benchmark und Orientierung für neue Lebenszyklusanalysen für PV-Technologien liefern. / The special need of a sustainable energy supply in mind the technologies of the renewable source solar energy, especially photovoltaics (PV) is main subject of the present thesis. Using the inexhaustible, clean and “freely delievered” power from the sun solar devices may play a major role in a cleaner future, but, on the other hand, they are still energy consuming and expensive in their production which consequently demands a whole life cycle perspective when assessing this technology. For a closer look at PV the methodology of Environmental Life Cycle Costing (ELCC) is introduced by following three theoretical points of view. Namely these are sustainability, life cycle thinking and the three dimensional nature of this tool by regarding environmental, economic and technical aspects in their interaction. Based on theoretical elements of Life Cycle Assessment and Life Cycle Costing in combination with the technical background of photovoltaics main requirements and steps for performing an ELCC for PV are described. By executing software based content analysis the defined framework is checked (and modified) against a choice of 135 existing studies analyzing the life cycle of PV technologies from an environmental or economic perspective. As a result the main elements of an ELCC for PV, e.g. environmental impact categories and economic indicators, are identified (methodological feedback). Within the next step the existing studies are rated by their “quality” regarding the environmental, economic and more general parts of an ELCC for PV in order to create an inventory of life cycle studies for PV. This inventory is structured by technologies as well as quality of content respecting ELCC and might be used for further analyses. At this stage the results propose the possibility of a first estimate of the present status of ELCC for PV: until now there is a good pool of existing analyses of the life cycle of PV systems. But from an ELCC perspective the examination of common hot spots and trade offs between economic and environmental aspects should be expanded. The theoretical framework of ELCC for PV, the encoded studies and the inventory of life cycle analyses for PV are now the starting point for further analyses, especially of the individual outcome within studies, which will then pose a benchmark for new life cycle studies of PV technology.
108

Environmental Life Cycle Costing (ELCC) für Produkte der Solarenergie: Die Verbindung von Life Cycle Assessment (LCA) und Life Cycle Costing (LCC) - from Cradle to Grave - angewandt auf die Photovoltaik. Anforderungen bei der Durchführung und aktueller Stand in der Praxis

Krause, Marcus January 2011 (has links)
Vor dem Hintergrund der zukünftigen Notwendigkeit einer nachhaltigen Energieversorgung beschäftigt sich die vorliegende Arbeit mit Technologien der regenerativen Energiequelle Solarenergie, insbesondere Photovoltaik (PV). Systeme zur Nutzung der unerschöpflich verfügbaren, sauberen und im Prinzip “frei Haus” gelieferten Energie der Sonne können eine bedeutsame Rolle in einer umweltverträglicheren Zukunft spielen. Allerdings ist die Herstellung der erforderlichen Komponenten heute i.d.R. noch energie- und kostenintensiv, weshalb für eine korrekte Bewertung dieser Technologien der gesamte Lebenszyklus betrachtet werden muss. Zur tieferen Analyse der PV wird die Methodik des Environmental Life Cycle Costing (ELCC) auf der Grundlage von drei Grundideen eingeführt. Konkret sind dies die Ausgangspunkte: Nachhaltigkeit, Lebenszyklusdenken und die Drei-Dimensionalität dieses Instrumentes durch die gemeinsame Betrachtung ökologischer, ökonomischer und technischer Aspekte in ihrem Zusammenspiel. Ausgehend von theoretischen Elementen der Ökobilanzierung (Life Cycle Assessment) und des Life Cycle Costings, verbunden mit den technischen Eigenschaften der Photovoltaik werden wichtigste Anforderungen und Schritte für die Durchführung eines ELCC für PV beschrieben. Mittels einer softwaregestützten Inhaltsanalyse wird im Anschluss der definierte Rahmen für ein ELCC für PV getestet (und modifiziert) gegen eine Auswahl von 135 bereits existierender Studien, die sich mit dem Lebenszyklus von PV-Technologien aus ökologischer und ökonomischer Sicht beschäftigen. Im Ergebnis hieraus können die wichtigsten Elemente eines ELCC für PV, wie beispielsweise ökologische Wirkungskategorien oder ökonomische Indikatoren, identifiziert werden (methodisches Feedback). In einem nächsten Schritt werden die Studien hinsichtlich ihrer “Qualität” bezogen auf ökologische, ökonomische und übergreifende Inhalte eines ELCC für PV bewertet. Auf diese Weise kann ein Inventar von Lebenszyklusanalysen für PV erstellt werden, das nach den Technologien und der inhaltlichen Qualität bezüglich eines ELCC strukturiert ist und für weitere Analysen als Grundlage dienen kann. Aus den bisherigen Ergebissen kann eine erste Einschätzung zum aktuellen Stand des ELCC für PV in der Literatur vorgenommen werden: Es existiert bereits ein großer Pool von Studien, die sich mit dem Lebenszyklus der PV beschäftigen. Mit Blick auf die Anforderungen eines ELCC für PV besteht jedoch Nachholbedarf in der Verbindung und gemeinsamen Betrachtung von hot spots und trade offs aus ökologischer und ökonomischer Perspektive. Der definierte theoretische Rahmen für ein ELCC für PV, die kodierten Studien sowie das erstellte Inventar von Lebenszyklusanalysen der PV können nun als Grundlage für weitere Analysen dienen. Insbesondere eine inhaltliche Auswertung der konkreten Ergebnisse von Studien kann so einen Benchmark und Orientierung für neue Lebenszyklusanalysen für PV-Technologien liefern. / The special need of a sustainable energy supply in mind the technologies of the renewable source solar energy, especially photovoltaics (PV) is main subject of the present thesis. Using the inexhaustible, clean and “freely delievered” power from the sun solar devices may play a major role in a cleaner future, but, on the other hand, they are still energy consuming and expensive in their production which consequently demands a whole life cycle perspective when assessing this technology. For a closer look at PV the methodology of Environmental Life Cycle Costing (ELCC) is introduced by following three theoretical points of view. Namely these are sustainability, life cycle thinking and the three dimensional nature of this tool by regarding environmental, economic and technical aspects in their interaction. Based on theoretical elements of Life Cycle Assessment and Life Cycle Costing in combination with the technical background of photovoltaics main requirements and steps for performing an ELCC for PV are described. By executing software based content analysis the defined framework is checked (and modified) against a choice of 135 existing studies analyzing the life cycle of PV technologies from an environmental or economic perspective. As a result the main elements of an ELCC for PV, e.g. environmental impact categories and economic indicators, are identified (methodological feedback). Within the next step the existing studies are rated by their “quality” regarding the environmental, economic and more general parts of an ELCC for PV in order to create an inventory of life cycle studies for PV. This inventory is structured by technologies as well as quality of content respecting ELCC and might be used for further analyses. At this stage the results propose the possibility of a first estimate of the present status of ELCC for PV: until now there is a good pool of existing analyses of the life cycle of PV systems. But from an ELCC perspective the examination of common hot spots and trade offs between economic and environmental aspects should be expanded. The theoretical framework of ELCC for PV, the encoded studies and the inventory of life cycle analyses for PV are now the starting point for further analyses, especially of the individual outcome within studies, which will then pose a benchmark for new life cycle studies of PV technology.
109

Assessment of the sustainability of bioenergy production from algal feedstock

Aitken, Douglas January 2014 (has links)
Growing concerns regarding the impact of fossil fuel use upon the environment and the cost of production have led to a growth in the interest of obtaining energy from biomass. 1st and 2nd generation biomass types, however, are often criticised for their high energy requirements and environmental impacts. Algal biomass is considered a 3rd generation biomass which does not require arable land for cultivation, typically has a high productivity and can be converted to a wide variety of energy carriers. Despite research on the concept of producing energy from algal biomass dating back to the 1960s there has been limited commercial development and the environmental advantages are still in doubt. This thesis investigated the potential of algal biomass as a source of bioenergy feedstock by considering the cultivation and processing of localised species of algae and applying life cycle assessment (LCA) methodology to algal biofuel production systems. Experiments were conducted to examine the productivity of a wild algal species in wastewater and the potential recoverable bioenergy yields. The LCA studies drew together data from external studies, commercial databases, industrial reports and experimental work to assess the environmental impacts and the energy balance for each system considered. The thesis investigated the generation of biofuel from both freshwater algal biomass and marine algal biomass. For both cases, the current state of research was examined and the gaps determined. Existing studies suggest the high intensity of microalgal biomass production (fertiliser requirements, high energy harvesting) greatly reduces the overall sustainability. Part of this thesis therefore investigated the possibility of a low input system of microalgal cultivation. A recommended approach was suggested using local species cultivated in wastewater as the nutrient source and a conversion strategy based on the characteristics of the dominant species. The practicality and effectiveness of cultivating and processing locally grown algal biomass under low input conditions was determined by experiments that were conducted in the laboratory. Algal biomass was collected locally and cultivated in the laboratory using agricultural effluent as the nutrient source. The productivity of the algae was monitored alongside the uptake of nutrients. The effluent provided a good media for the cultivation of the wild algae and the nitrogen and phosphorous loading of the effluent was reduced by as much as 98% for NH4+ and 90% for PO4³-. The algal biomass was also tested for its potential as a feedstock for bioethanol production as well as biochar alongside pyrolysis oils and gases. Compared to alternative biomass types tested, the algal biomass appeared to be a good candidate for bioethanol production providing a 38% recovery of bioethanol. The biomass appeared a less favourable substrate for energy recovery from pyrolysis but this process could be considered for carbon biofixation. The sustainability of incorporating microalgal cultivation in wastewater treatment was tested by conducting a life cycle assessment of a large scale system. The life cycle assessment used Haifa wastewater treatment plant in Israel as a case study. The study compared algal cultivation with energy recovery to conventional nutrient removal (A2O process) for enhanced nutrient removal within the wastewater treatment plant. It was found that the use of algal ponds for nutrient removal compared favourably to conventional treatment under specific conditions. These conditions were: the algal biomass is converted to both biodiesel and biogas and the algal biomass is converted to biodiesel, bioethanol and biogas. In these cases the energy balance was greater and the global warming potential and eutrophication potential were less. The conventional nutrient removal was, however, found to be the better method in terms of the acidification potential. Despite being the favourable method of nutrient removal the cultivation and processing of algae relies upon several key assumptions: high year round growth of algae, no contamination and access to a high land area for the cultivation ponds. The sustainability of recovering bioenergy from the cultivation of macroalgae was also tested. A life cycle assessment was conducted investigating the energy return on investment and six environmental impacts for three cultivation methods and three process streams to convert the biomass to bioenergy. Cultivation and processing in Chile was used as a case study due to the depth of knowledge and availability of data. The cultivation scenarios were: bottom cultivation of Gracilaria chilensis, the long line cultivation of Gracilaria chilensis and the long line cultivation of Macrocystis pyrifera. The processing streams were: bioethanol, biogas and both bioethanol and biogas. Most of the data used in the life cycle assessment was obtained from studies conducted in Chile and from communication with local fisherman. It was found that the bottom cultivation of Gracilaria chilensis and conversion to bioethanol and biogas produced the best energy return on investment (2.95) and was most beneficial in terms of the environmental impacts considered. Alternative circumstances were also considered which included new research (untested on a large scale) related to the value used for productivity and conversion of the biomass. This analysis indicated that an EROI of 10.3 could be achieved for the long-line cultivation of Macrocystis pyrifera and conversion to bioethanol and biogas alongside very limited environmental impacts. This result relies, however, upon favourable assumptions that have not yet been proven on a large scale. The work conducted in this thesis highlights the potential of recovering energy from algal biomass. The experimental work and life cycle analysis of freshwater algal cultivation demonstrates the importance of using wastewater treatment as added value to the system. Maximising energy recovery by using a combination of conversion techniques was also shown to be key in providing the most sustainable solution. The sustainability of energy produced from macroalgae was established as being preferable to several conventional energy sources. Innovative methods to improve the system were also shown to greatly enhance the concept.
110

An examination of the acceptance, adoption, and diffusion of smartphone devices with senior citizens.

Reneau, James M. 01 January 2013 (has links)
This research looked at the process of the diffusion of an innovation in the context of smartphones with American senior citizens. The subject of diffusion, or spread of a technology, is a rich and varied topic with more than 60 years of research. Much of this diffusion research does not go beyond the study of the original acceptance of a new idea. An on-line and face-to-face questionnaire was used to collect data from 155 seniors on the entire process of diffusion. The questionnaire was adaptive in nature, focusing questions directly at participants based on where they were in the diffusion process. The scope of the study was limited to two areas: 1) to verify or refute the findings of the Senior Technology Acceptance & Adoption Model (STAM) in the setting of a more diverse population of seniors and the different technology of modern smartphones than the original small population of South African seniors using mobile-phones and 2) to look at the phenomenon of discontinuance of use after adoption. The results show that seniors exhibit a much broader range of influences, behaviors, and motivations than the STAM model showed. Confirmed usefulness, ease of use, and other facilitating conditions play a significant role in how a technology moved from mere use to either being fully accepted or finally rejected. This research adds to the body of knowledge regarding the diffusion of technology, specifically adoption in seniors. Many existing models did not include the complete process by shortening the initial exploration and ignoring the discontinuance. These issues have been specifically addressed in a newly proposed model, the Senior Innovation Domestication and Life-cycle Model (SIDLM).

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