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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.
701

An Experimental Investigation in the Mitigation of Flutter Oscillation Using Shape Memory Alloys

McHugh, Garrett R. January 2016 (has links)
No description available.
702

Applying project risk management principles to manage business start-up risk : a proposed training tool / Ratoeba Piet Ntema

Ntema, Ratoeba Piet January 2014 (has links)
Generally, it is accepted that small businesses are becoming increasingly important in terms of employment, wealth creation, and the development of innovation in the global economy. Unfortunately, many small businesses fail before reaching maturity, mainly due to inadequate entrepreneurial skills to establish and grow their businesses. It is, therefore, vital to understand the management abilities that are required to enable start-up businesses to survive. This study's main aim is to propose a risk management training tool to assist business start-ups to mitigate their risks. This is expected to allow for increased business start-up success rates. The aim of the proposed risk mitigation tool will be to provide training to allow small business owners to deal with challenges they face. The tool should assist with minimising the risk of failure and therefore support increased growth and survival of small businesses. The research questions aimed at achieving the primary objective deal with: *The typical risks per start-up phase for small businesses *How to mitigate the risk per business start-up phase *How best to teach entrepreneurs to identify and manage business start-up risk per phase. The research was conducted by means of a literature and empirical study. The literature study reviewed business start-up phases, challenges facing start-up businesses, project life cycle phases, critical factors leading to project failure, project risk management, and principles of serious games design. The challenges facing start-up businesses were tested empirically in practice by means of a measurement instrument, and subsequently evaluated. The size of the sample used was 58 entrepreneurs from start-up businesses. The results from this study show a need for improvements in the following skills for start-up owners/managers: risk management skills, entrepreneurial skills, people management skill, business management skill, and financial management skill. This study proposed a tool to teach entrepreneurs to identify and manage start-up risks per phase. The tool is proposed to be a blended model tool. Thus, the tool consists of the workshop part; whereby, the facilitator is face-to-face with the trainee, and post-training application-based support. / MSc (Computer Science), North-West University, Vaal Triangle Campus, 2014
703

A critical evaluation of the environmental law framework applicable to carbon capture and storage in South Africa / Edward Arthur Rea

Rea, Edward Arthur January 2013 (has links)
The objective of this study is to conduct a critical evaluation of the environmental law framework applicable to carbon capture and storage (hereafter CCS) in South Africa. The discussion begins by confirming that CCS has a place in environmental law as a mitigation measure. The inclusion of CCS in the clean development mechanism could incentivise the development of environmental law frameworks for CCS in South Africa. Implementation of CCS is gradual, with only eight large scale integrated CCS projects having been established around the world. An appreciation of key scientific concepts is helpful for an understanding of the CCS process. The CCS project life cycle and related impacts on the environment provide a context for discussion of the legal requirements accompanying the CCS life cycle. The Constitution of the Republic of South Africa, 1996 and the National Environmental Management Act 107 of 1998 constitute appropriate framework legislation for CCS. Decision 3/CMP.1, Modalities and procedures for a clean development mechanism as defined in Article 12 of the Kyoto Protocol adopted by the Conference of the Parties serving as the Meeting of the Parties to the Kyoto Protocol held at Montreal from 28 November to 10 December 2001 March 2006 provides international legal requirements accompanying the project life cycle against which the South African legal framework is examined. Some provisions of additional South African laws and policies will be applicable to CCS depending on the nature of the specific CCS project, but specific regulations may have to be developed for South Africa. Policy documents have been gradually bringing clarity to the way forward in arriving at a legal framework for CCS, and by reference to existing local legislation and international guidance, an environmental law framework for CCS can be developed for South Africa. / LLM (Environmental Law and Governance), North-West University, Potchefstroom Campus, 2014
704

Applying project risk management principles to manage business start-up risk : a proposed training tool / Ratoeba Piet Ntema

Ntema, Ratoeba Piet January 2014 (has links)
Generally, it is accepted that small businesses are becoming increasingly important in terms of employment, wealth creation, and the development of innovation in the global economy. Unfortunately, many small businesses fail before reaching maturity, mainly due to inadequate entrepreneurial skills to establish and grow their businesses. It is, therefore, vital to understand the management abilities that are required to enable start-up businesses to survive. This study's main aim is to propose a risk management training tool to assist business start-ups to mitigate their risks. This is expected to allow for increased business start-up success rates. The aim of the proposed risk mitigation tool will be to provide training to allow small business owners to deal with challenges they face. The tool should assist with minimising the risk of failure and therefore support increased growth and survival of small businesses. The research questions aimed at achieving the primary objective deal with: *The typical risks per start-up phase for small businesses *How to mitigate the risk per business start-up phase *How best to teach entrepreneurs to identify and manage business start-up risk per phase. The research was conducted by means of a literature and empirical study. The literature study reviewed business start-up phases, challenges facing start-up businesses, project life cycle phases, critical factors leading to project failure, project risk management, and principles of serious games design. The challenges facing start-up businesses were tested empirically in practice by means of a measurement instrument, and subsequently evaluated. The size of the sample used was 58 entrepreneurs from start-up businesses. The results from this study show a need for improvements in the following skills for start-up owners/managers: risk management skills, entrepreneurial skills, people management skill, business management skill, and financial management skill. This study proposed a tool to teach entrepreneurs to identify and manage start-up risks per phase. The tool is proposed to be a blended model tool. Thus, the tool consists of the workshop part; whereby, the facilitator is face-to-face with the trainee, and post-training application-based support. / MSc (Computer Science), North-West University, Vaal Triangle Campus, 2014
705

A critical evaluation of the environmental law framework applicable to carbon capture and storage in South Africa / Edward Arthur Rea

Rea, Edward Arthur January 2013 (has links)
The objective of this study is to conduct a critical evaluation of the environmental law framework applicable to carbon capture and storage (hereafter CCS) in South Africa. The discussion begins by confirming that CCS has a place in environmental law as a mitigation measure. The inclusion of CCS in the clean development mechanism could incentivise the development of environmental law frameworks for CCS in South Africa. Implementation of CCS is gradual, with only eight large scale integrated CCS projects having been established around the world. An appreciation of key scientific concepts is helpful for an understanding of the CCS process. The CCS project life cycle and related impacts on the environment provide a context for discussion of the legal requirements accompanying the CCS life cycle. The Constitution of the Republic of South Africa, 1996 and the National Environmental Management Act 107 of 1998 constitute appropriate framework legislation for CCS. Decision 3/CMP.1, Modalities and procedures for a clean development mechanism as defined in Article 12 of the Kyoto Protocol adopted by the Conference of the Parties serving as the Meeting of the Parties to the Kyoto Protocol held at Montreal from 28 November to 10 December 2001 March 2006 provides international legal requirements accompanying the project life cycle against which the South African legal framework is examined. Some provisions of additional South African laws and policies will be applicable to CCS depending on the nature of the specific CCS project, but specific regulations may have to be developed for South Africa. Policy documents have been gradually bringing clarity to the way forward in arriving at a legal framework for CCS, and by reference to existing local legislation and international guidance, an environmental law framework for CCS can be developed for South Africa. / LLM (Environmental Law and Governance), North-West University, Potchefstroom Campus, 2014
706

An investigation into the factors that nurses working in critical care units perceive as leading to burnout

Mbuthia, Nickcy Nyaruai 01 February 2010 (has links)
Burnout is reflected in pathological emotional depletion and maladaptive detachment that is a secondary result of exposure prolonged occupational stress. It is comprised of three dimensions, namely, emotional exhaustion, depersonalization and reduced personal accomplishment. It is becoming increasingly recognized as one of the most serious occupational hazards for nurses who work in critical care units. The objectives of this study are to assess the prevalence of burnout among a sample of nurses who worked in the critical care units in a particular hospital in Kenya, to analyze factors that contributed to the development of burnout and to identify measures for the mitigation of burnout. For this study, the researcher utilized a mixed methods research design in two phases. Phase one assessed the prevalence of burnout in nurses working in the critical care units by making use of the Maslach Burnout Inventory – Human Services Survey. Focus groups discussions were then held in Phase two to investigate the factors that the nurses perceived as the main causes of burnout and to solicit their ideas about it could be mitigated. Convenience sampling and purposive sampling were used in the two phases of the study respectively. / Health Studies / M.A. (Health Studies)
707

Establishing a pilot plant facility for post combustion carbon dioxide capture studies

Kritzinger, Liaan Rudolf 03 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Carbon dioxide (CO2) is seen as one of the main contributors to global warming. The use of fossil fuels for power production leads to large quantities of carbon dioxide being released into the atmosphere. The released CO2 can, however, be captured by retrofitting capture units downstream from the power plant called Post Combustion Carbon Dioxide Capturing. Post combustion CO2 capture can involve the reactive absorption of CO2 from the power plant flue gas steam. Reactive solvents, such as monoethanolamine (MEA), are used for capturing the CO2 and the solvent is regenerated in a desorber unit where the addition of heat drives the reverse reaction, releasing the captured CO2. However, the large energy requirement for solvent regeneration reduces the viability of employing CO2 capture on an industrial scale. This study focused on establishing a facility for CO2 capture studies – the main aim being the construction and validation of the results produced by the pilot plant facility. A secondary aim of this study was developing an Aspen Plus® Simulation method that would simplify simulating the complex CO2 capture process. Results from the simulation were to be compared to that of the pilot plant experiments. A pilot plant facility with a closed gas system, allowing gas recycling from both the absorber and the stripping columns, was set up. The absorber column (internal diameter = 0.2 m) was set up to allow one to obtain information regarding gas- and liquid temperatures and compositions at various column heights. Online gas analysers are used for analysing the gas composition at various locations in the absorber column. The pilot plant was initially commissioned with 20 weight % MEA in aqueous solution; however the main validation experiments were conducted with 30 weight % MEA in aqueous solution. 30 weight % MEA (aq) is generally used as the reference solvent for pilot plant studies. Pilot plant results with regards to the carbon dioxide concentration profiles for the absorber column as well as the regeneration energy requirement and capture rates compared well to literature data. The Aspen Plus® simulation was also set up and validated using published pilot plant data. The comparison of the pilot plant results from this study, to the results from the Aspen Plus® Simulation, showed good agreement between the two. The Aspen Plus® Simulation could further be used to validate pilot plant data that has been gathered outside the range of reported CO2 capture efficiencies. The Aspen Plus®model was evaluated at liquid-to-gas ratios of 1.7 and regeneration energies matching the pilot plant results. It was found that the model under predicts the capture efficiency of CO2 with an average of 4.0%. The model was corrected for this error at liquid-to-gas ratios of 2 and the fit of the model to pilot plant results improved considerably (R2-value = 0.965). Pilot plant repeatability was investigated with both 20 weight %- and 30 weight % MEA in aqueous solution. Temperature- and gas concentration profiles from the absorber column showed good repeatability. The maximum deviation of the regeneration energy and the capture efficiency from the calculation means were ±0.72% and ±1.40% respectively. The aims of this study have been met by establishing, and validating the results of a pilot plant facility for carbon dioxide capture studies. It has been shown that the pilot plant produces repeatable results. Results from the Aspen Plus® Simulation were validated and also match results from the established pilot plant setup. The simulation may prove to provide valuable information regarding the optimal operating conditions for the pilot plant and may aid in performing a full parametric study on the CO2 capture process. / AFRIKAANSE OPSOMMING: Koolstofdioksied (CO2) word geklassifiseer as een van die bekendste kweekhuisgasse wat ʼn groot bydra lewer tot aardverwarming. Die gebruik van fossielbrandstowwe om na die energiebehoeftes van die mens om te sien lei daartoe dat groot hoeveelhede koolstofdioksied, hoofsaaklik vanaf kragstasies, vrygestel word in die atmosfeer. Daar is verskeie maniere hoe die CO2 uit die uitlaatgas van kragstasies verwyder kan word – die vernaamste hiervan is bekend as die Na-verbranding opvangs metode. Die opvangs van CO2 na verbranding van fossielbrandstowwe vir kragproduksie kan vermag word deur van reaktiewe absorpsie tegnieke gebruik te maak. Mono-etanol-amien (MEA) kan vir hierdie doeleindes aangewend word deur dit, in ʼn absorpsiekolom, in kontak te bring met die CO2. Die gereageerde oplosmiddel word geregenereer deur die oplosmiddel te verhit in ʼn stropingskolom. ʼn Bykans suiwer CO2 stroom word vrygestel. Die implementering van hierdie opvangtegniek op industriële skaal lei egter tot groot energieverliese vir die kragstasies. Die hoofrede hiervoor is die hoeveelheid energie wat benodig word om die oplosmiddel te regenereer vir hergebruik. Die hoofdoel van hierdie studie was gemik op die oprigting en inwerkstelling van 'n navorsingsfasiliteit vir studies aangaande die na-verbranding opvangs van CO2. Dit het behels die ontwerp, konstruksie en stawing van gelewerde resultate met resultate in die literatuur. 'n Sekondêre doel van hierdie studie was die metode-ontwikkeling vir die opstel van 'n Aspen Plus® Model wat die simulasie van die CO2 opvangsproses met ʼn reaktiewe oplosmiddel, MEA, vereenvoudig. Gesimuleerde resultate is vergelyk met resultate uit die literatuur. Die toetsaanleg, met 'n geslote gas stelsel, maak voorsiening vir die hersirkulering van gas wat vir eksperimentele doeleindes gebruik word. Die absorpsie kolom (interne diameter van 0,2 m) is opgestel sodat informasie aangaande die gas- en vloeistof temperature, sowel as gas- en vloeistof komposisies vanaf verskillende kolomhoogtes, bekom kan word. ʼn Aanlyn CO2 analiseerder word gebruik om vir CO2 in die prosesgas te analiseer. Die toetsaanleg is aanvanklik in bedryf gestel met ʼn 20 massa % MEA in waterige oplossing; die hoof eksperimente is egter uitgevoer deur van 30 massa % MEA in waterige oplossing gebruik te maak. Die laasgenoemde oplosmiddel word algemeen gebruik in die CO2 opvangs verwante navorsingsveld. Die resultate van die toetsaanleg, vergelyk goed met resultate in die literatuur. Die gesimuleerde Aspen Plus® resultate is ook vergelyk met resultate in die literatuur en die gevolgtrekking is gemaak dat die simulasie gebruik kan word om redelike akkurate voorspellings van die werklike prosesresultate te gee. Die simulasie is verder ook gebruik om resultate, verkry vanaf die opgerigte toetsaanleg, te verifieer en ʼn goeie ooreenstemming tussen die gesimuleerde en die eksperimentele resultate is waargeneem. ʼn Verder gevolgtrekking aangaan die Aspen Plus® simulasie metode was dat dit in die toekoms ʼn groot doel kan dien in die optimeringsproses van toetsaanlegte waar navorsing aangaande die na-verbranding opvang van CO2 gedoen word. Die Aspen Plus® model is geëvalueer by ‘n vloeistof-tot-gas-verhouding van 1,7 en ooreenstemmende toetsaanleg resultate, aangaande die hoeveelheid energie wat ingesit is vir die regenerasie van die oplosmiddel. Die onakkuraathede in die model, met betrekking tot die voorspelling van die hoeveelheid CO2 wat vasgevang sal word, is hierdeur bepaal en die model is daarvoor aangepas. Resultate van die verbeterde model vergelyk baie goed met die toetsaanleg resultate – ʼn R2-waarde van 0.965. Die herhaalbaarheid van die toetsaanleg resultate is ondersoek en ʼn goeie herhaalbaarheid van die temperatuur- en CO2 konsentrasieprofiele is verkry. Die toetsaanleg dui ook goeie herhaalbaarheid met betrekking tot die effektiwiteit waarmee die CO2 uit ʼn gasstroom verwyder word (± 1,40%), sowel as die hoeveelheid energie wat benodig word vir regenerering van die oplosmiddel (± 0,72%). Die doelwitte van hierdie studie is bereik deur die oprigting en verifiëring van resultate gelewer deur 'n toetsaanleg vir studies aangaande die na-verbrandingsopvang van CO2. Die herhaalbaarheid van toetaanleg resultate is bewys. Resultate van die Aspen Plus® simulasie stem ooreen met resultate in die literatuur sowel as resultate van die toetsaanleg wat opgerig is in hierdie studie.
708

The (un)sustainability of  hotel breakfast buffets : Food and its potential to mitigate greenhouse gas emissions in the context of tourism

Gube, Marlene January 2016 (has links)
Tourism and food are two sectors that have major impact on the environment, including the amount of global greenhouse gases (GHGs) they emit. The potential of the tourism sector to mitigate greenhouse gases through adaptation strategies of food supply and consumption at breakfast buffets in hotels is the major field of investigation in the current study.   This thesis contributes an empirical analysis that uses knowledge from fieldwork in a touristic area in Sweden. The empirical work of this study consists of two steps. First, measuring the (un)sustainability of breakfast buffets in hotels, using the FOODSCALE method, determining potential pathways toward a less greenhouse gas emission intensive food supply and second, to distinguish tourist interest to adopt toward a more climate friendly diet away from home. As food consumption patterns of tourists are considered as critical contributors to greenhouse gas emissions, changes toward a more environmental friendly diet are urgently needed helping substantially in mitigating emissions of GHGs. However, this field has been sparsely explored which made it an interesting and important area for current research in tourism studies.  The results and analysis showed that sustainable food consumption patterns of tourists can be encouraged through breakfast buffets. However, this is depending on a couple of determinants which have to be applied and fulfilled by breakfast buffets in hotels. Tourists interest to adapt toward a more climate friendly diet while being on holidays is depending on their eating habits and their interest in environmental sustainability issues. With the help of the 3 identified guest groups it can be determined that the majority of tourists' is willing to give up carbon-intensive eating habits and change their behavior when being on holidays. Hotels can act as role models, promoting more sustainable behaviour through sustainable food offers at breakfast buffets. The idea of hotels acting as role models focuses on encouraging beneficial decision-making, such as adopting food consumption patterns toward a carbon-neutral diet.
709

Climate Transition in Municipalities : Identifying ways to assess transition processes through indicators

Ackerfors, Linnea, Hederén, Amanda January 2016 (has links)
Climate change has been recognised as one of the biggest challenges of our time. To prevent further climate change impacts, nations at COP21 further stressed the need to mitigate their greenhouse gas emissions enough to prevent dangerous temperature rise and to adapt societies to become more resilient. Municipals have been found important actors in this transition due to their power to inflict change on a local level. However, there is a lack of methods to assess how transition is made due to the fact that transition is a fairly new approach to managing climate change combined with a lack of completed transitions in municipalities. The purpose of this study is to explore the use of indicators as a method to assess municipal transition processes. Focusing on two Swedish municipalities that have been deemed vulnerable but at the same time apt to combat climate change, this study uses a triangulation of methods that are divided into two phases. The first phase uses a literature review in order to create a scientifically based list of transition indicators. The second phase uses document analyses and interviews in order to test the indicators and analyse transition process on a local level. The study revealed that there are multiple barriers and triggers for transition such as conflicting interests, economic factors, political steering, knowledge building- and awareness and long term perspectives, but that there also exist important tools for municipal transition in the form of networks through multi-level collaborations and plans/objectives. The findings in this study also suggests that the use of indicators as a method to assess transition could be viable, but that it is limited due to its contextual nature and lack of successful transitions to compare with. / Klimatförändringar har ansetts vara en av de viktigaste utmaningarna i vår tid. För att förhindra att vidare skador av klimatförändringarna kom nationer som deltog i COP21 överens om att minska sina växthusgaser tillräckligt mycket för att förhindra farliga temperaturförhöjningar och att anpassa sina samhällen till resilienta enheter. Kommuner anses vara viktiga aktörer i denna omställning då de har makt att påverka förändringar på en lokal nivå. Dock saknas metoder för att bedöma hur omställning utförs då omställning är ett nytt angreppssätt kombinerat med en brist på genomförda omställningar. Syftet med denna uppsats är att utforska användningen av indikatorer som metod för att bedöma omställningsprocesser. Genom att använda en triangulering av metoder som delats upp i två faser fokuserar studien på två svenska kommuner som har fastställts som känsliga inför klimatförändringarna men även att ha förmågan att hantera dem. Den första fasen består av en litteraturstudie som skapade en vetenskaplig grund som berörde en global och nationell nivå. Den andra fasen bestod av en dokumentsanalys och intervjuer för att utforska omställningsprocesser på en lokal nivå. Studien visar på att det finns flera barriärer och drivkrafter för omställning som konkurrerande intressen, ekonomiska faktorer, politisk styrning, kunskaps byggande- och medvetenhet och långsiktighet men även att det fanns verktyg som var viktiga för kommunal omställning som nätverk genom samarbeten på olika nivåer och planer/mål. Slutligen visar även studien på att användningen av indikatorer som metod för att bedömma omställning skulle kunna vara möjligt men att begränsningar finns då metoden dels är kontextberoende men även att det är svårt att göra jämförelser då ingen fullförd omställning har skett.
710

Promoting lower-carbon lifestyles : the role of personal values, climate change communications and carbon allowances in processes of change

Howell, Rachel Angharad January 2013 (has links)
Climate change is a pressing problem and substantial reductions in the greenhouse gas emissions that cause it are necessary to avert the worst impacts predicted. The UK has targeted an 80% reduction from 1990 emissions levels by 2050. This thesis investigates how to promote behavioural changes that will reduce emissions associated with individuals’ lifestyles, which comprise a significant proportion of the UK total. The thesis begins by appraising whether and how climate change communications, specifically films, can succeed in changing attitudes and behaviour. The impacts on viewers of the film The Age of Stupid were assessed using a fourstage panel survey. Increased concern, motivation to act, and sense of agency felt immediately after seeing the film did not persist, but respondents reported some behavioural changes. The longer-term follow-up suggests that behavioural intentions do not necessarily translate into action, but also revealed issues concerning the reliability of participants’ causal attributions of their behaviour. These and other challenges of conducting longitudinal studies of behavioural change related to climate change communications are discussed. The thesis then uses a model of behavioural change transposed from health psychology to analyse the processes of change employed or depicted by four climate change films, in order to identify more generally the strengths and limitations of films as means to promote mitigation action, and to demonstrate the potential utility of the model in the field of proenvironmental behaviour change. The issue is then considered from the opposite angle, with an examination of what has motivated individuals who have already adopted lower-carbon lifestyles. Qualitative research reveals that protecting ‘the environment’ per se is not the primary value stimulating most interviewees’ action; typically they were more concerned about the impacts of climate change on people in developing countries. Although analysis of a survey instrument showed that biospheric values are important to the participants, they tended to score altruistic values significantly higher. Thus it may not be necessary to promote biospheric values to encourage lower-carbon lifestyles. The final element of the work involved researching the opinions of members of Carbon Rationing Action Groups, seeking to understand what can be learned from their experiences of living with a carbon allowance, and the implications that the findings may have for potential government policies, especially personal carbon trading. The thesis concludes that, given the scale of action required, the difficulties individuals face when considering whether and how to adopt lower-carbon behaviours, and the limited impact of initiatives such as Carbon Rationing Action Groups and The Age of Stupid beyond a relatively small circle of people who tend to exhibit particular traits (such as a preference for frugality), significant UK emissions reductions will necessitate far-reaching legislation that will impact on everyday practices and behaviour.

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