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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.
281

To Be or Not to Be: The Impact of Depression on Adolescents

Schreiner, Terri 09 February 2008 (has links)
No description available.
282

Documentation of Biodiversity Impacts (Including Cumulative Biodiversity Impacts) in Environmental Impact Statements

Bhatia, Sarika 08 1900 (has links)
In the United States, biodiversity impact assessment has historically received little attention. Responding in 1993, the Council on Environmental Quality (CEQ) released guidelines on incorporating biodiversity into environmental impact assessment under the National Environmental Policy Act of 1969. The objectives of the study here were to identify the level of documentation of biodiversity impact assessment in sample Environmental Impact Statements (EISs); identify whether in the years following the release of 1993 CEQ guidelines any significant changes have taken place in assessment of biodiversity; identify deficiencies, and if the need exists, formulate appropriate recommendations and approaches for addressing biodiversity in EISs. The study involved a systematic review of 30 EISs published since the release of CEQ guidelines, and five EISs published prior to it. The review involved answering a series of standard questions, which attempted to ascertain the level of biodiversity impacts included in each impact statement. Trends in approaches to biodiversity impact assessment were investigated and deficiencies summarized. The analysis resulted in a series of recommendations for improving the manner in which biodiversity impact assessment can be approached.
283

One-Year Test-Retest Reliability of the Online Version of ImPACT in High School Athletes

Elbin, R. J., Schatz, Philip, Covassin, Tracey 01 November 2011 (has links)
Background: The ImPACT (Immediate Post-Concussion Assessment and Cognitive Testing) neurocognitive testing battery is a popular assessment tool used for concussion management. The stability of the baseline neurocognitive assessment is important for accurate comparisons between postconcussion and baseline neurocognitive performance. Psychometric properties of the recently released online version of ImPACT have yet to be established; therefore, research evaluating the reliability of this measure is warranted.Purpose: The authors investigated the 1-year test-retest reliability of the ImPACT online version in a sample of high school athletes.Study Design: Case series; Level of evidence, 4Methods: A total of 369 varsity high school athletes completed 2 mandatory preseason baseline cognitive assessments approximately 1 year apart as required by their respective athletics program. No diagnosed concussion occurred between assessments.Results: Intraclass correlation coefficients (ICCs) for ImPACT online indicated that motor processing speed (.85) was the most stable composite score, followed by reaction time (.76), visual memory (.70), and verbal memory (.62). Unbiased estimates of reliability were consistent with ICCs: motor processing speed (.85), reaction time (.76), visual memory (.71), and verbal memory (.62).Conclusion: The online ImPACT baseline is a stable measure of neurocognitive performance across a 1-year time period for high school athletes. These reliability data for online ImPACT are higher than the 2-year ICCs previously reported from the desktop version.Clinical Relevance: It is recommended that the ImPACT baseline assessment (both desktop and online) continue to be updated every 2 years. The online version of ImPACT appears to be a stable measure of neurocognitive performance over a 1-year period, and systematic evaluation of its stability over a 2-year period is warranted.
284

A socio-economic impact assessment of the future closure of a diamond mine in Namaqualand, South Africa : planning for mine closure a decade in advance

Mackenzie, Andrew G January 1992 (has links)
Bibliography: pages 56-7. / De Beers Namaqualand Mines (DBNM) have appointed the Environmental Evaluation Unit to undertake an impact assessment of mine closure. According to recent estimates DBNM anticipate that their diamond mining operations in Namaqualand will have to be closed in approximately ten years time. DBNM requested that the study focus on the socio-economic implications of mine closure within the regional context of Namaqualand and not the broader context of South Africa. It is anticipated that the results and recommendations of the study will be used by DBNM in planning for mine closure. The aims and objectives of the study are: 1) To assess the socio-economic consequences of future mine closure. 2) To recommend actions that will mitigate the impacts of mine closure. The aims and objectives of this report are to: 1) Fulfil the academic requirements of the degree. 2) Assess and evaluate information collected during the data collection phase of this project (contained in the Baseline Information Report) and to present these findings clearly and concisely, highlighting significant impacts and options for mitigation. 3) To communicate these findings in a way as would make them useful to both the client as the decision-maker and the interested and affected parties.
285

Socio-economic impact assessment of the proposed closure of De Beers Namaqualand diamond mines by the year 2005 : main report

Greeff, Karen Liane January 1993 (has links)
Bibliography: pages 65-67. / In 1991 the Environmental Evaluation Unit (EEU) of the University of Cape Town was appointed by DBNM to undertake a socio-economic impact assessment of the proposed closure of DBNM by the year 2005. According to De Beers, the source of viable diamond ore is finite and unless technological advances or market fluctuations make the reserves economically viable, the mine has no option but to shut down its operations. This is anticipated to have major social and economic impacts on the region and DBNM. The emphasis is on regional impacts i.e. the Namaqualand Magisterial District. However, due to the concentration of employees originating from the Herschel District in the Transkei, special cognisance is taken of impacts likely to occur there. Therefore, the two main purposes of this report are to: * identify and evaluate the potential major socio-economic impacts arising out of the closure of De Beers Namaqualand Mines (DBNM), * determine mitigatory action which will reduce negative impacts and optimize positive impacts.
286

An environmental evaluation system in the planning process of quarries in South Africa

Hoogervorst, Arend January 1985 (has links)
The historical framework and background to the process of approving quarries for construction materials in South Africa is examined in depth. In order to produce a proposed Environmental Evaluation System for the assessment of quarries in South Africa, the interrelationships of Quarries and the Environment are briefly examined philosophically. Environmental Impact terminology and Environmental Impact Assessment methodologies, techniques and procedures are also discussed.
287

Ultimate Cavity Dynamics of Hydrophobic Spheres Impacting on Free Water Surfaces

Mansoor, Mohammad M. 12 1900 (has links)
Cavity formation resulting from the water-entry of solid objects has been the subject of extensive research owing to its practical relevance in naval, military, industrial, sports and biological applications. The cavity formed by an impacting hydrophobic sphere normally seals at two places, one below (deep seal) and the other above the water surface (surface seal). For Froude numbers , the air flow into the resulting cavity is strong enough to suck the splash crown above the surface and disrupt the cavity dynamics before it deep seals. In this research work we eliminate surface seals by means of a novel practice of using cone splash-guards and examine the undisturbed transient cavity dynamics by impact of hydrophobic spheres for Froude numbers ranging . This enabled the measurement of extremely accurate pinch-off heights, pinch-off times, radial cavity collapse rates, and jet speeds in an extended range of Froude numbers compared to the previous work of Duclaux et al. (2007). Results in the extended regime were in remarkable agreement with the theoretical prediction of scaled pinch-off depth, and experimentally derived pinch-off time for . Furthermore, we investigated the influence of confinement on cavity formation by varying the cross-sectional area of the tank of liquid. In conjunction with surface seal elimination we observed the formation of multiple pinch-off points where a maximum of four deep seals were obtained in a sequential order for the Froude number range investigated. The presence of an elongated cavity beneath the first pinch-off point 5 resulted in evident "kinks" primarily related to the greatly diminished air pressure at the necking region caused by supersonic air flows (Gekle et al. 2010). Such flows passing through second pinch-offs were also found to choke the cavities beneath the first pinch- off depths causing radial expansion and hence disappearance of downward jets.
288

The practical application of theoretical concepts of integrated environmental management (IEM) : a case study of a proposed rock quarry in a peri-urban area

Larsen, J January 1993 (has links)
Bibliography: pages 105-107. / This dissertation forms part of the requirements for the degree of MSc in Environmental Science and was supervised by Professor R Fuggle, Head of Department of the Department of Environmental and Geographical Science. The dissertation describes and examines the practical application of integrated environmental management (IEM) by analyzing a case study. IEM is a methodology developed in South Africa under the direction of the Council for the Environment, the purpose of which is to incorporate environmental considerations into all aspects of planning and development. A guideline document on the implementation of IEM was published in 1989 (Council for the Environment, 1989(A)), and later updated and a set of six guideline documents was published in 1992 (Department of Environment Affairs, 1992 (A) to (F)). The case study is the proposed development of a rock quarry in a peri-urban area near Johannesburg, South Africa. It was implemented in accordance with the original version of lEM. The availability of the updated guidelines and the experience gained in the case study provided potential for comparison between the original and updated procedures. Other points of relevance regarding the case study are that the site is situated in a rapidly developing area, and could therefore cause significant social impacts; the study was conducted at the most detailed level of the original IEM procedure (Class 1 ); and involved public participation, which has been emphasised in the updated IEM procedure.
289

Sputnik Planitia as a probe for Pluto’s internal evolution.

Camille Adeene Denton (14216183) 06 December 2022 (has links)
<p>  </p> <p>Though we cannot directly characterize the internal structure of Pluto, its interior can be probed remotely by observing its response to impact-induced deformation. The formation and evolution of giant impact basins like Sputnik Planitia, Pluto’s massive 1200 x 1400-km-diameter impact basin, is a unique geologic process that links the dwarf planet’s interior structure to the basin’s morphology and overall longevity. Its large size, location, and relationship to tectonic features has led researchers to suggest that Sputnik Planitia preserves evidence of a large subsurface ocean, while possible antipodal features observed on Pluto’s far side raise questions of how stress waves from impact may have traveled through Pluto’s interior, which remains somewhat unconstrained. In this dissertation, I strive to understand the relationship between the formation and evolution of Sputnik Planitia and the thermal and mechanical structure of Pluto at a variety of scales. The years following New Horizons’ flyby of the Pluto system in 2015 have yielded more questions than answers about the state of Pluto’s interior, including the thickness and thermal structure of its ice shell, the possible presence of a liquid water ocean, and the composition of its rocky core. I use impact simulations to reproduce the unique physics associated with impact cratering and further investigate which internal structures are consistent with the cratering record, as well as finite element models to explore the postimpact evolution of Pluto’s largest impact basin and probe the mechanical and thermal structure of the ice shell in more detail. With these tools, I show that the formation and evolution of Sputnik Planitia is consistent with the presence of a hydrated core and thick subsurface ocean in Pluto’s interior. The results of this dissertation contribute to understanding the origin, evolution, and interior of Pluto as well as other icy moons, ocean worlds, and large Kuiper Belt Objects in our solar system, and has direct implications for future exploration of other such worlds in our solar system.</p>
290

Assessing the utility of environmental impact assessments as a strategy for global sustainable development

Akol, Doris January 2001 (has links)
No description available.

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