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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

The development, implementation and performance evaluation of an innovative residential load management system / Abraham Zacharias Dalgleish

Dalgleish, Abraham Zacharias January 2009 (has links)
The power utility of South Africa, Eskom, expected a supply shortfall of approximately 400MW between February and August 2006 in the Western Cape. The peak of the crisis was in mid-winter (June to August). This shortfall was firstly caused when Eskom experienced a breakdown on the one of the two nuclear supply units. Secondly the remaining of the Koeberg units was due for refuelling which necessitated the shut-down of the reactor. No electricity was therefore generated by both units. It was clear that if electricity demand was not effectively curbed, extensive power outages would be experienced; which was the case. Various demand side management (DSM) programmes were rolled-out to address lighting, switching from electricity to gas for cooking, compensating customers that could generate own electricity, energy efficiency and load curtailment in the education, commercial, and industrial sectors, as well as an extensive energy efficiency campaign. It is shown in this study that the most constrained periods were expected during the evening peak and was a consequence of electricity consumption in the residential sector. The residential evening peak is very prominent and primarily caused by water heating, cooking, space heating, lighting, and appliances. None of the mentioned programmes focused on the residential evening peak. Traditional residential DSM technologies were almost impossible to implement in the short timeframe because there are more than 625,000 residences in the Western Cape. A solution was looked for that could be implemented in a relatively short period to address the residential evening peak. This study focuses on the development, implementation, and performance evaluation of Power Alert – An innovative residential load management system. The need for such a system was identified and the expected impact was determined through a feasibility study. Power Alert was designed to be a link between Eskom and the public through the national television broadcaster. It was operational during the whole Western Cape winter. A methodology to determine the impact of Power Alert was also developed to demonstrate the actual load reductions. The methodology was applied and Power Alert demonstrated that it was a valuable residential load management tool that could be designed and implemented in a much shorter time than conventional residential DSM measures. / Thesis (Ph.D. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2010.
32

The development, implementation and performance evaluation of an innovative residential load management system / Abraham Zacharias Dalgleish

Dalgleish, Abraham Zacharias January 2009 (has links)
The power utility of South Africa, Eskom, expected a supply shortfall of approximately 400MW between February and August 2006 in the Western Cape. The peak of the crisis was in mid-winter (June to August). This shortfall was firstly caused when Eskom experienced a breakdown on the one of the two nuclear supply units. Secondly the remaining of the Koeberg units was due for refuelling which necessitated the shut-down of the reactor. No electricity was therefore generated by both units. It was clear that if electricity demand was not effectively curbed, extensive power outages would be experienced; which was the case. Various demand side management (DSM) programmes were rolled-out to address lighting, switching from electricity to gas for cooking, compensating customers that could generate own electricity, energy efficiency and load curtailment in the education, commercial, and industrial sectors, as well as an extensive energy efficiency campaign. It is shown in this study that the most constrained periods were expected during the evening peak and was a consequence of electricity consumption in the residential sector. The residential evening peak is very prominent and primarily caused by water heating, cooking, space heating, lighting, and appliances. None of the mentioned programmes focused on the residential evening peak. Traditional residential DSM technologies were almost impossible to implement in the short timeframe because there are more than 625,000 residences in the Western Cape. A solution was looked for that could be implemented in a relatively short period to address the residential evening peak. This study focuses on the development, implementation, and performance evaluation of Power Alert – An innovative residential load management system. The need for such a system was identified and the expected impact was determined through a feasibility study. Power Alert was designed to be a link between Eskom and the public through the national television broadcaster. It was operational during the whole Western Cape winter. A methodology to determine the impact of Power Alert was also developed to demonstrate the actual load reductions. The methodology was applied and Power Alert demonstrated that it was a valuable residential load management tool that could be designed and implemented in a much shorter time than conventional residential DSM measures. / Thesis (Ph.D. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2010.
33

The benefits of viewing sacred versus preferred landscapes

Burger, Donald Allen 05 1900 (has links)
Restoration landscape theories propound the observation that landscape mitigates human emotion, mental functioning, and behaviour. Those environments that positively affect these spheres are called "restorative". In recent years, many attempts have been made to quantify restorative landscapes, so that landscape architects and others can replicate them in the manipulated environment. An understanding of how certain combinations of landscape attributes affect humans is important in knowing the ramifications of certain designs. A major finding in recent years is that preferred landscapes—or those high in scenic beauty—are generally more restorative than less-attractive environments. One realm of the environment not dealt with, however, is the sacred landscape. One reason for this is the relative difficulty in narrowing down the term “sacred” to something measurable. The purpose of this thesis is to investigate the nature of sacred landscapes, and then to test sacred landscapes against preferred landscapes to measure their restorative potential. This testing involved subjecting participants to a psychological stressor, and then exposing them to slides rated highly in either sacredness or preference. A control group was also tested, but viewed a blank screen rather than images. Implications of this research impact both researchers and practitioners in the fields of landscape architecture, environmental psychology, public land management, and visual resource management. This study found that sacred landscapes are very restorative, although not quite as restorative as environments that rate highly in scenic beauty. This confirms previous research efforts, and opens the study of restorative environments to other landscape typologies as well.
34

All in Good Time: Exploring Change in Neanderthal Behavioural Complexity

Langley, Michelle Unknown Date (has links)
Since their discovery 150 years ago, Neanderthals have been considered incapable of behavioural change and innovation. Traditional synchronic approaches to the study of Neanderthal behaviour have perpetuated this view and shaped our understanding of their lifeways and eventual extinction. In this thesis I implement an innovative diachronic approach to the analysis of Neanderthal faunal extraction, technology and symbolic behaviour as contained in the archaeological record of the critical period between 80,000 and 30,000 years BP. The thesis demonstrates patterns of change in Neanderthal behaviour which are at odds with traditional perspectives and which are consistent with an interpretation of increasing behavioural complexity over time, an idea that has been suggested but never thoroughly explored in Neanderthal archaeology. Demonstrating an increase in behavioural complexity in Neanderthals provides much needed new data with which to fuel the debate over the behavioural capacities of Neanderthals and the first appearance of Modern Human Behaviour in Europe. It supports the notion that Neanderthal populations were active agents of behavioural innovation prior to the arrival of Anatomically Modern Humans in Europe and, ultimately, that they produced an early Upper Palaeolithic cultural assemblage (the Châtelperronian) independent of modern humans. Overall, this thesis provides an initial step towards the development of a quantitative approach to measuring behavioural complexity which provides fresh insights into the cognitive and behavioural capabilities of Neanderthals.
35

Negotiating fences : interaction in advisory encounters for nature conservation /

Bergeå, Hanna Ljunggren, January 2007 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 4 uppsatser.
36

"Där man bor tycker man det är bra" : barns geografier i en segregerad stadsmiljö /

van der Burgt, Danielle, January 2006 (has links)
Diss. Uppsala : Uppsala universitet, 2007.
37

Environmental policy and the properties of Environmental damages : applications to economic growth and international environmental problems /

Zehaie, Ficre, January 2005 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2005. / Härtill 5 uppsatser.
38

Aspects of precommercial thinning : private forest owners' attitudes and alternative practices /

Fällman, Karin, January 2005 (has links) (PDF)
Diss. (sammanfattning). Umeå : Sveriges lantbruksUniversity. / Härtill 4 uppsatser.
39

Collaborative learning for sustainable development of agri-food systems /

Ljung, Magnus, January 2001 (has links) (PDF)
Diss. Uppsala : Sveriges lantbruksuniv., 2001.
40

Kyrkogården i framtiden : ur ungdomars perspektiv /

Sörensen, Ann-Britt, January 2003 (has links) (PDF)
Lic.-avh. Uppsala : Sveriges lantbruksuniv.

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