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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

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.
32

Meeting the ageing aircraft challenge

Crowley, Christopher Keith, Aerospace, Civil & Mechanical Engineering, Australian Defence Force Academy, UNSW January 2004 (has links)
&quotMeeting the ageing aircraft challenge&quot is not just about safety, not just about effectiveness, and not just about economy of support. It is about proactive and reactive optimization of all three service goals throughout long life cycles that span 20 or 30 years, or more, and typically, beyond the originally intended design life. It is therefore about organizational attitudes towards ongoing trend analysis and condition monitoring, and pervading cost benefit assessments of all forms of human innovation across what the author describes as 'the eight sustaining disciplines for long aerospace life cycles', including scientific and technological developments, and opportunities for reliability growth or 'refresh'. Complacency is the root cause of all problems with the design, maintenance and support of all modern infrastructure, and therefore life cycle planners and minders are required to be an enthusiastic but nervous lot - always hoping for the best, but planning for the worst impact of 'Mr Murphy'. Murphy thrives on complacency, is in bed with uncertainty, and never forgets (as we do often) that imperfection (no matter how small) breeds unreliability traps that patiently wait to surprise at some stage along the life cycle journey. He has the upper hand. ...Our best weapons against Murphy are continual, total picture and longer-term situational awareness; caution, vigilance, innovation and collaboration. This research study and thesis is intended as a broad and comprehensive management philosophy, a guide and checklist - a broad scrape of everything 'so deep', rather than coverage of any one-niche aspect of the ageing aircraft challenge in great depth. It includes a brief and simple strategic setting for Australian Military Aerospace requirements, and spans a three axes management philosophy: 1. a toolbox of eight sustaining disciplines, 2. trend analysis and 3. time-cost-benefit assessment. Along with complacency, the prime ageing aircraft 'killers' are identified, as are the key ageing aircraft 'age multipliers'. The eight sustaining disciplines are explained in varying depth, according to their broad significance to the ageing aircraft condition and life cycle. The ever-ubiquitous bathtub reliability curve - the key to understanding, predicting and controlling life cycle behaviour (including costs) - is emphasized. Engineering life cycle minding and capability management are broad focus areas. The eight areas of attention identified for this broad study are: 1. Aerospace design requirements and trends, 2. Science and technology opportunities, 3. Airworthiness, engineering and maintenance philosophy, 4. Reliability behaviour, 5. Operational use and abuse patterns, 6. Logistics support and managing obsolescence, 7. Technical workforce and organizational attitudes (requirements and outlook), and 8. Life cycle costing and budgeting. This thesis primarily draws attention to the fundamental driver of life cycle behaviour - reliability. The critical dependency that life cycle control and prediction has on consistent and high quality trend data collection and analysis is emphasized throughout, and the now pressing need for better identification of ageing aircraft cost growth drivers, and their containment, is linked to reliability trend awareness, manipulation and intervention. The human dimension is included - including coverage of organizational attitudes and what it takes to be a 'high reliability organization'. There are no magic or easy answers to the ageing aircraft condition and challenge. Trend analysis has to be done from the bottom up, system by system, for each fleet type. But over time, with consistent trend data collection, patterns emerge within the sophisticated and stochastic systems behaviour that that ageing aircraft play out. These patterns enable ongoing management of the long life cycle to be more confidently predicted, more assured and with best possible cost growth containment. The best, perhaps only, path to least surprises and best cost containment is now being re-identified in some military aviation organizations as a mature and evolving RAM engineering and RCM framework. RAM-RCM may well be the only recovery from what some admit is a death spiral of ageing aircraft cost growth.
33

Optimal spatial sampling of infrastructure condition a life-cycle-based approach under uncertainty /

Gong, Liying. January 2006 (has links)
Thesis (Ph. D.)--Ohio State University, 2006. / Available online via OhioLINK's ETD Center; full text release delayed at author's request until 2011 Aug 11
34

A service life analysis of U.S. Coast Guard C-130 aircraft

Duff, Jonathan B. January 2003 (has links)
Thesis (M.S.)--Air Force Institute of Technology, 2003. / Title from title screen (viewed May 10, 2004). "March 2003." Vita. "AFIT/GAQ/ENS/03-02." "ADA413132"--URL. Includes bibliographical references (leaves 132-135). Also issued in paper format.
35

Life cycle cost analysis of pavements : state-of-the-practive /

Guven, Zeynep. January 2006 (has links)
Thesis (M.S.)--Clemson University, 2006. / Includes bibliographical references (p. 133-136). Also available online.
36

Comparative analysis of the VRF system and conventional HVAC systems, focused on life-cycle cost

Park, Jaesuk 13 January 2014 (has links)
As concern for the environment has been dramatically raised over the recent decade, all fields have increased their efforts to reduce impact on environment. The field of construction has responded and started to develop the building performance strategies as well as regulations to reduce the impact on the environment. HVAC systems are obviously one of the key factors of building energy consumption. This study investigates the system performance and economic value of variable refrigerant flow (VRF) systems relative to conventional HVAC systems by comparing life-cycle cost of VRF systems to that of conventional HVAC systems. VRF systems consist mainly of one outdoor unit and several indoor units. The outdoor unit provides all indoor units with cooled or heated refrigerant; with these refrigerants, each indoor unit serves one zone, delivering either heating or cooling. Due to its special configuration, the VRF system can cool some zones and heat other zones simultaneously. This comparative analysis covers six building types—medium office, standalone retail, primary school, hotel, hospital, and apartment—in a eleven climate zones—1A Miami, 2A Houston, 2B Phoenix, 3A Atlanta, 3B Las Vegas, 3C San Francisco, 4A Baltimore, 4B Albuquerque, 4C Seattle, 5A Chicago, and 5B Boulder. Energy simulations conducted by EnergyPlus are done for each building type in each climate zone. Base cases for each simulation are the reference models that U.S. Department of Energy has developed, whereas the alternative case is the same building in the same location with a VRF system. The life-cycle cost analysis provides Net Savings, Savingto- Investment ratio, and payback years. The major findings are that the VRF system has an average of thirty-nine percent HVAC energy consumption savings. As for the results of the life-cycle cost analysis, the average of simple payback period is twelve years.
37

Meeting the ageing aircraft challenge

Crowley, Christopher Keith, Aerospace, Civil & Mechanical Engineering, Australian Defence Force Academy, UNSW January 2004 (has links)
&quotMeeting the ageing aircraft challenge&quot is not just about safety, not just about effectiveness, and not just about economy of support. It is about proactive and reactive optimization of all three service goals throughout long life cycles that span 20 or 30 years, or more, and typically, beyond the originally intended design life. It is therefore about organizational attitudes towards ongoing trend analysis and condition monitoring, and pervading cost benefit assessments of all forms of human innovation across what the author describes as 'the eight sustaining disciplines for long aerospace life cycles', including scientific and technological developments, and opportunities for reliability growth or 'refresh'. Complacency is the root cause of all problems with the design, maintenance and support of all modern infrastructure, and therefore life cycle planners and minders are required to be an enthusiastic but nervous lot - always hoping for the best, but planning for the worst impact of 'Mr Murphy'. Murphy thrives on complacency, is in bed with uncertainty, and never forgets (as we do often) that imperfection (no matter how small) breeds unreliability traps that patiently wait to surprise at some stage along the life cycle journey. He has the upper hand. ...Our best weapons against Murphy are continual, total picture and longer-term situational awareness; caution, vigilance, innovation and collaboration. This research study and thesis is intended as a broad and comprehensive management philosophy, a guide and checklist - a broad scrape of everything 'so deep', rather than coverage of any one-niche aspect of the ageing aircraft challenge in great depth. It includes a brief and simple strategic setting for Australian Military Aerospace requirements, and spans a three axes management philosophy: 1. a toolbox of eight sustaining disciplines, 2. trend analysis and 3. time-cost-benefit assessment. Along with complacency, the prime ageing aircraft 'killers' are identified, as are the key ageing aircraft 'age multipliers'. The eight sustaining disciplines are explained in varying depth, according to their broad significance to the ageing aircraft condition and life cycle. The ever-ubiquitous bathtub reliability curve - the key to understanding, predicting and controlling life cycle behaviour (including costs) - is emphasized. Engineering life cycle minding and capability management are broad focus areas. The eight areas of attention identified for this broad study are: 1. Aerospace design requirements and trends, 2. Science and technology opportunities, 3. Airworthiness, engineering and maintenance philosophy, 4. Reliability behaviour, 5. Operational use and abuse patterns, 6. Logistics support and managing obsolescence, 7. Technical workforce and organizational attitudes (requirements and outlook), and 8. Life cycle costing and budgeting. This thesis primarily draws attention to the fundamental driver of life cycle behaviour - reliability. The critical dependency that life cycle control and prediction has on consistent and high quality trend data collection and analysis is emphasized throughout, and the now pressing need for better identification of ageing aircraft cost growth drivers, and their containment, is linked to reliability trend awareness, manipulation and intervention. The human dimension is included - including coverage of organizational attitudes and what it takes to be a 'high reliability organization'. There are no magic or easy answers to the ageing aircraft condition and challenge. Trend analysis has to be done from the bottom up, system by system, for each fleet type. But over time, with consistent trend data collection, patterns emerge within the sophisticated and stochastic systems behaviour that that ageing aircraft play out. These patterns enable ongoing management of the long life cycle to be more confidently predicted, more assured and with best possible cost growth containment. The best, perhaps only, path to least surprises and best cost containment is now being re-identified in some military aviation organizations as a mature and evolving RAM engineering and RCM framework. RAM-RCM may well be the only recovery from what some admit is a death spiral of ageing aircraft cost growth.
38

Meeting the ageing aircraft challenge

Crowley, Christopher Keith, Aerospace, Civil & Mechanical Engineering, Australian Defence Force Academy, UNSW January 2004 (has links)
&quotMeeting the ageing aircraft challenge&quot is not just about safety, not just about effectiveness, and not just about economy of support. It is about proactive and reactive optimization of all three service goals throughout long life cycles that span 20 or 30 years, or more, and typically, beyond the originally intended design life. It is therefore about organizational attitudes towards ongoing trend analysis and condition monitoring, and pervading cost benefit assessments of all forms of human innovation across what the author describes as 'the eight sustaining disciplines for long aerospace life cycles', including scientific and technological developments, and opportunities for reliability growth or 'refresh'. Complacency is the root cause of all problems with the design, maintenance and support of all modern infrastructure, and therefore life cycle planners and minders are required to be an enthusiastic but nervous lot - always hoping for the best, but planning for the worst impact of 'Mr Murphy'. Murphy thrives on complacency, is in bed with uncertainty, and never forgets (as we do often) that imperfection (no matter how small) breeds unreliability traps that patiently wait to surprise at some stage along the life cycle journey. He has the upper hand. ...Our best weapons against Murphy are continual, total picture and longer-term situational awareness; caution, vigilance, innovation and collaboration. This research study and thesis is intended as a broad and comprehensive management philosophy, a guide and checklist - a broad scrape of everything 'so deep', rather than coverage of any one-niche aspect of the ageing aircraft challenge in great depth. It includes a brief and simple strategic setting for Australian Military Aerospace requirements, and spans a three axes management philosophy: 1. a toolbox of eight sustaining disciplines, 2. trend analysis and 3. time-cost-benefit assessment. Along with complacency, the prime ageing aircraft 'killers' are identified, as are the key ageing aircraft 'age multipliers'. The eight sustaining disciplines are explained in varying depth, according to their broad significance to the ageing aircraft condition and life cycle. The ever-ubiquitous bathtub reliability curve - the key to understanding, predicting and controlling life cycle behaviour (including costs) - is emphasized. Engineering life cycle minding and capability management are broad focus areas. The eight areas of attention identified for this broad study are: 1. Aerospace design requirements and trends, 2. Science and technology opportunities, 3. Airworthiness, engineering and maintenance philosophy, 4. Reliability behaviour, 5. Operational use and abuse patterns, 6. Logistics support and managing obsolescence, 7. Technical workforce and organizational attitudes (requirements and outlook), and 8. Life cycle costing and budgeting. This thesis primarily draws attention to the fundamental driver of life cycle behaviour - reliability. The critical dependency that life cycle control and prediction has on consistent and high quality trend data collection and analysis is emphasized throughout, and the now pressing need for better identification of ageing aircraft cost growth drivers, and their containment, is linked to reliability trend awareness, manipulation and intervention. The human dimension is included - including coverage of organizational attitudes and what it takes to be a 'high reliability organization'. There are no magic or easy answers to the ageing aircraft condition and challenge. Trend analysis has to be done from the bottom up, system by system, for each fleet type. But over time, with consistent trend data collection, patterns emerge within the sophisticated and stochastic systems behaviour that that ageing aircraft play out. These patterns enable ongoing management of the long life cycle to be more confidently predicted, more assured and with best possible cost growth containment. The best, perhaps only, path to least surprises and best cost containment is now being re-identified in some military aviation organizations as a mature and evolving RAM engineering and RCM framework. RAM-RCM may well be the only recovery from what some admit is a death spiral of ageing aircraft cost growth.
39

Reliability allocation and apportionment : addressing redundancy and life-cycle cost /

Nowicki, David R. January 1993 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 33-38). Also available via the Internet.
40

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.

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