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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.
201

Water Conservation for Domestic Users: With Special Reference to Warm Desert Climates

DeCook, K. James, Haney, Richard A., Stone, Mary Ann, Doran, Thomas E., Fangmeier, D. D., Fazio, Steve, Frobel, Ronald K., Halderman, Allan, Johnson, Gordon, Jones, Warren, Kneebone, William, Matlock, W. G., Phillips, Robert A., Sacamano, Charles, Welchert, W. T., Brooks, Frank, Brice, Robert, Graffius, Paul January 1977 (has links)
A Handbook Prepared by The University of Arizona for the City of Tucson.
202

A model residential energy efficiency program

Jeter, Teresa M. January 1995 (has links)
The opportunity for reducing energy expenditures in homes has never been greater nor has the need been more pressing. Based on the current analysis of weatherization programs, millions of houses do not receive energy efficiency measures and houses that are being weatherized are not receiving the kinds of measures that generate the greatest energy savings. Many of these problems are attributed to program policies, regulations and funding limitations. Given these critical issues. The creative project is a model residential energy efficiency program. Its purpose is to serve as a guide for planning, designing, developing and implementing the kinds of residential energy efficiency programs that will maximize services and benefits. More specifically, the model will assist in the design and implementation of programs that are effective, efficient and can deliver the “right” energy measures to “any” house that needs them. A community in a small Midwestern city was selected to help demonstrate the various components of the model program. / Department of Urban Planning
203

A comparison of heuristic and optimal reserve selection algorithms used in systematic conservation planning /

Vanderkam, Robert P. D. January 1900 (has links)
Thesis (M.A.) - Carleton University, 2005. / Includes bibliographical references (p. 126-136). Also available in electronic format on the Internet.
204

Landscape and architectural devices for energy-efficient South Africa suburban residential design

Bothma, Johan. January 2004 (has links)
Thesis (M.L. Arch.)--University of Pretoria, 2004. / Title from opening screen (viewed March 14, 2005). Summaries in Afrikaans and English. Includes bibliographical references.
205

Conservation of South African tortoises with emphasis on their apicomplexan haematozoans, as well as biological and metal-fingerprinting of captive individuals

Cook, Courtney Antonia 02 November 2012 (has links)
Ph.D. / South Africa has the highest biodiversity of tortoises in the world with possibly an equivalent diversity of apicomplexan haematozoans, which to date have not been adequately researched. Prior to this study, five apicomplexans had been recorded infecting southern African tortoises, including two haemogregarines, Haemogregarina fitzsimonsi and Haemogregarina parvula, and three haemoproteids, Haemoproteus testudinalis, Haemoproteus balazuci and Haemoproteus sp. A. The taxonomy of all of these species was questionable, and therefore one goal of this study was to examine at least some in great detail with the view to resolving taxonomic issues. This involved using a number of techniques such as light microscopy and image analysis, transmission electron microscopy, and molecular analysis. Outcomes were the transfer of one Haemogregarina species (Haemogregarina fitzsimonsi) to the genus Hepatozoon, the suggestion that the genus Hemolivia might be more appropriate for another haemogregarine (Haemogregarina parvula), the synonymisation of two known species of Haemoproteus (Haemoproteus balazuci with Haemoproteus testudinalis), and the naming of a third haemoproteid (Haemoproteus natalensis Cook, Smit and Davies, 2010). In addition, a likely new species of haemogregarine (Haemogregarina sp. A.) was described. To achieve all this, 367 tortoises were collected representing 62% of the species and all five genera, of South African tortoises. Tortoises were both wild (287) and captive (80), with these being both live (270) and dead (97) when taken. They were located in four different provinces, including Gauteng, KwaZulu-Natal, the Northern and the Western Cape, and in four different biomes (semi-arid grassland, Kalahari desert, subtropical thorn bushveld, and coastal endemic fynbos). Light photomicroscopy examination of Giemsa stained peripheral blood smears prepared from the subcarapacial vessels of live tortoises allowed for descriptions and comparisons of the observed haematozoans. Of the live tortoises, 14.8% had haemogregarines, including 13.3% with H. fitzsimonsi, 0.7% with H. parvula, and 0.7% with a previously unknown, intraleucocytic, Haemogregarina sp. A. A further 1.1% had haemoproteids, including 0.7% with Hp. testudinalis/Hp. balazuci and 0.4% with Haemoproteus sp. A. The host and locality records of previously described haematozoan species were increased and records for likely new species provided. Subtropical areas (KwaZulu-Natal) compared to arid regions (Northern Cape) presented with a higher diversity of apicomplexans, along with a higher prevalence of ticks, possible vectors of the tortoise blood parasites. Overall, male tortoises had the highest haematozoan and tick prevalences compared to females and juveniles,
206

Analysis and Ethical Conservation of a Roman Statue Head in the Scripps College Permanent Collection

Raskin, Shaina 01 January 2015 (has links)
Unprovenanced and undocumented antiquities play a large roll in the international trade of antiquities, a billion dollar sector of the art market. The removal of these antiquities from their source countries creates many problems for the academic community and the standards put in place to eliminate illegal activity. An analysis of an ancient Roman statue head of Livia was used to demonstrate the usefulness of such an legally acquired undocumented antiquity. A visual analysis was first conducted on the Scripps Livia residing within the Scripps Permanent collection by creating comparisons to other known portraits of Livia. A chemical analysis was then conducted to continue verifying authenticity. With the use of a Scanning Electron Microscope, four samples removed from the sculpture were analyzed for elemental composition. Based on the data gathered from these analyses recommendations for new acquisition policies were created for the purpose of ethically researching and displaying the Scripps Livia.
207

Effects of drought and grazing on land bird populations in South Texas

Lipschutz, Maia Lynn 30 August 2016 (has links)
<p> Breeding bird surveys were conducted on 7 properties belonging to 2 ranches in South Texas. Using these data I calculated temporal trends, and tested the effects of total May&ndash;April precipitation and cattle stocking rate on avian abundance. Trends were calculated for each ranch, the East Foundation and King Ranch, individually due to different range and wildlife management practices. Total avian abundance increased significantly on the 3 East Foundation properties between 2008 and 2015. During 39 breeding bird surveys, 16,441 individual birds of 88 species were recorded. Non-breeding bird surveys were also conducted on East Foundation properties, an increasing trend in total avian abundance was also calculated from these data. Total breeding bird abundance was stable on the 4 King Ranch properties between 2005 and 2013. A total of 19,162 individual birds of 87 species were recorded during 40 breeding bird surveys. The combined effect of livestock use and precipitation had a significant effect on total avian abundance on all King Ranch properties, and on the abundance of some individual species and groups. </p>
208

An analysis of the demography and habitat usage of Roatan's spiny-tailed iguana, Ctenosaura oedirhina

Campbell, Ashley B. 10 September 2016 (has links)
<p> The Roat&aacute;n Spiny-tailed Iguana (<i>Ctenosaura oedirhina </i>) is endemic to the 146-km<sup>2</sup> island of Roat&aacute;n, Honduras. Harvesting for consumption, fragmentation of habitat, and predation by domestic animals threaten this lizard. It is currently listed as Endangered by the International Union for Conservation of Nature (IUCN), as threatened by the Honduran government, and is on Appendix II of the Convention on International Trade in Endangered Species (CITES). This species has been geographically fragmented and genetically isolated into small subpopulations that are declining in density. With data gathered from use/availability surveys, resource selection functions were used to identify habitats and environmental variables associated with their presence. Results indicate that protection from harvesting is the most important factor in determining their distribution. These high-density populations are currently restricted to &sim;0.6 km<sup>2</sup>. Organisms living in small, isolated populations with very restricted ranges are at higher risk of extirpation due</p><p> to various direct and indirect forces. Mark-recapture-resight surveys and distance sampling have been used to monitor the populations since 2010 and 2012 respectively. The data show that the high-density populations are declining. The current population size is estimated to be 4130-4860 individuals in 2015. A population viability analysis (PVA) was conducted to identify the most pressing threats and specific life history traits that are affecting this decline. The analysis estimates that if current trends persist, the species will be extinct in the wild in less than ten years. Adult mortality is a main factor and female mortality specifically characterizes this decline. In order for this species to persist over the next fifty years, adult mortality needs to be reduced by more than 50%. A lack of enforcement of the current laws results in the persistence of the main threat, poaching for consumption, thus altering the species distribution and causing high adult mortality. This is complicated by social customs and a lack of post primary education. Management changes could mitigate this threat and slow the population decline. Recommendations include an education campaign on the island, increased enforcement of the current laws, and breeding of <i>C. oedirhina in situ</i> and <i> ex situ</i> for release into the wild.</p>
209

Design guidelines for habitat reintroduction within agricultural landscapes: A demonstration study

Grant, David B. 13 December 2016 (has links)
In southern Manitoba, there is a significant need to reintroduce diverse, ecologically sound environments to redress serious events of watershed habitat loss and accompanying landscape deterioration. Soil erosion, water pollution, and declining wildlife populations are the results of current agricultural practices and policy. The adoption of ecologically sound farming and water management practices compatible with the environmental requirements of native plant and animal communities will restore stability to the local ecosystem, diversity and interest to the landscape and a stronger sense of place for people of the region. This study describes the methods for effectively reintroducing habitat as part of a farms drainage network and the positive effect this has on soil and water conservation, both of which ultimately stimulate increased agricultural production.
210

Effectiveness of passive energy interventions in improving physical learning environments in South African schools

16 March 2010 (has links)
M.Sc. / South Africa is in the midst of an energy crisis. The national energy provider is unable to provide the capacity currently demanded in South Africa. Although the construction of new electricity plants is planned, it does not solve the immediate problem. A large amount of energy is used to provide thermally comfortable indoor environments using conventional methods such as air-conditioning units. Energy efficiency is an environmentally friendly solution for South Africans to reduce the demand for electricity. In the context of the current situation in South Africa, significance can be given to investigations that explore viable methods of reducing energy consumption in buildings, while maintaining or improving thermal performance through passive energy interventions. This study was conducted with the goal of quantifying and demonstrating technologies that simultaneously attempt to improve energy efficiency (through avoiding the use of energy intensive heating/cooling units) and improving the physical learning environment in prefabricated classrooms in South Africa, through the use of passive energy retrofits. This study forms one of the initial case studies conducted within the framework of the Enerkey Sustainable Megacities pilot programme. Reflective roof coatings and ceiling insulation were used to retrofit eight prefabricated classrooms at Garsfontein Primary School, Tshwane. Monitoring was performed of temperature conditions in two control and eight experimental classrooms. The resulting data were used to compare the thermal performance of the altered classrooms to the control classrooms. Empirical data sets included hourly average temperature readings in ten prefabricated classrooms and an externally located weather station. Average diurnal temperatures and temperature difference plots were created. A pre-retrofit questionnaire to determine occupants’ perceptions on the thermal indoor environments was distributed. Spot measurements of illumination levels in all ten classrooms were taken with a Lux meter. A cost-effectiveness analysis of the passive energy interventions was performed, using as a reference case an electrically powered air conditioning unit, specified to cool a 50 m2 classroom. Overall, the reflective roof coatings were not effective at reducing peak summer temperatures. A 50 mm thick plastic fibre insulation layer installed in the ceiling spaces consistently reduced peak indoor temperatures by ~2°C, while 50 mm thick expanded polystyrene ceiling boards were the most effective of the retrofits, consistently reducing peak indoor air temperatures by ~3°C. An analysis of the cost-effectiveness of passive interventions showed that, in comparison to the proposed alternative of installing electrically powered air-conditioning units, ceiling insulation is cost effective in varying extents, depending on the assumptions. However, in all cases considered, the cost advantage, expressed as Rand per degree Celsius comfort improvement, is considerable compared to the air conditioning unit. Light measurements indicated non-uniform illumination in the tested classrooms, from severe glare next to south facing windows, to dark areas well below minimum recommended levels. The overall illumination situation is unsatisfactory. Opportunities exist for improving illumination using passive and active energy efficient interventions. The hypothesis for this study was that passive energy interventions in prefabricated classrooms are energy- and cost-efficient means for improving the physical learning environment in South African schools. Ceiling insulation makes a valuable contribution towards improving indoor thermal environments in prefabricated classrooms. Ceiling insulation by itself, however, does not provide a comprehensive solution – the entire building envelope needs to be taken into consideration. A building energy digital simulation model could explore a range of interventions, to derive the overall most costeffective solution to improving indoor thermal environments in South African schools. Investigations of this nature will be conducted as part of the ongoing larger Enerkey project.

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