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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.
91

Resource scarcity and social identity in the political conflicts in Burundi

Jengo, Elisabeth Naito 03 1900 (has links)
Thesis (MA)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Since Burundi gained independence in 1962, this country has experienced periods of mass communal violence. Extensive scholarly research has focused on exploring the factors behind, and the nature of, the conflicts in Burundi from a socio-ethnic perspective. There has, however, been a persistent lack of attention paid to the inextricable relationship between environmental factors; particularly the scarcity of resources, coupled with rapid population growth; and Burundi‘s recent history of internal conflict. Noteworthy explanatory factors, which are often ignored in literature on the environment and conflict, have thus motivated this study. Burundi is an example of this reality because of a highly dependent agricultural economy and a constant growing population. This study used a descriptive analysis, as methodological tool; in order to gain an understanding of Burundi‘s land question - that is, how limited access to land and the constantly increasing population have led to environmental degradation, that served as motivational trigger factors for the violent political conflicts that occurred at various periods between 1965 and 1993 in this country. This study addresses this epistemological gap. In order to explore the nexus between environmental factors, land access, population growth and the political conflicts in Burundi, this study draws and builds upon Jared Diamond‘s (2005) five point framework of potential trigger factors to environmental collapse. Moreover, Diamond‘s (2005) ecocide theory argues that there are eight specific indicators to demonstrate how societies undermine themselves by damaging their own environment; thus resulting in an ecocide. This theory was applied to the two main environmental variables examined in this study. More specifically, this theoretical perspective provided a base for exploring how land issues, population growth, environmental degradation and political change can be understood as important precursors to the violent conflicts in Burundi. What may be surmised by this study; is that there is indeed a positive correlation between these forces, where the values of the independent variables (land access and population growth) are associated with the values of the dependent variable (violent conflict). This correlation, therefore, calls for an acknowledgement of the complexity of the Burundian conflicts and that ethnicity which has dominated contemporary conflict analysis is but one of several social rifts. / AFRIKAANSE OPSOMMING: Sedert Burundi in 1962 onafhanklikheid verkry het, het hierdie land periodes van massa gewelddadige politieke konflik ervaar. Uitgebreide wetenskaplike navorsing het daarop gefokus om die faktore agter die gebeure, sowel as die aard van die konflik in Burundi vanuit ‘n sosio-etniese perspektief, te ondersoek. Tog word daar steeds gebrekkige aandag geskenk aan die onlosmaaklike verhouding tussen omgewingsfaktore, veral gebrek aan hulpbronne, gepaardgaande met die voortgesette bevolkingsaanwas; asook Burundi se onlangse geskiedenis van interne konflik. Noemenswaardige gapings, wat dikwels in die verklarende literatuur geïgnoreer word, het dus hierdie studie gemotiveer. Burundi is ‘n voorbeeld van hierdie werklikheid omdat die land baie afhanklik van landbou is; as gevolg van die kontstante bevolkingsaanwas in die land. Hierdie navorsing het beskrywende analise as ‘n metodologiese instrument gebruik om insig te kry oor Burundi se grondkwessie – met ander woorde hoe die beperkte toegang tot grond en ‘n toenemende bevolkingsaanwas gelei het tot die agteruitgang van die omgewing. Bostaande faktore het as motiverende sneller faktore gedien, wat aanleiding gegee het tot die gewelddadige politieke konflik, wat gedurende verskillende periodes tussen 1965 en 1993 in hierdie land ontstaan het. Hierdie studie poog dus om hierdie epistomologiese gaping aan te spreek. Ten einde die verband (nexus) tussen omgewingsfaktore, grondbesit, bevolkingsaanwas en die politieke konflikte in Burundi te ondersoek, steun en bou hierdie studie voort op Jared Diamond (2005) se vyfpunt raamwerk van potensiële sneller faktore, wat lei tot omgewings ineenstorting. Verder beweer Diamond (2005) se omgewings uitwissing (ecocide) teorie dat daar agt spesifieke aanduidings is om te demonstreer hoe gemeenskappe hulself ondermyn deur hul eie omgewing te beskadig/vernietig: wat uitloop op omgewings uitwissing (ecocide). Hierdie teorie is aangewend in die twee hoof omgewings veranderlikes, wat in die studie/ navorsing ondersoek is. Hierdie teoretiese perspektief het ook spesifiek ‘n basis voorsien om te ondersoek hoe grondkwessies, bevolkingsaanwas, omgewings agteruitgang en politieke verandering verstaan kan word as belangrike aanwysers van die geweldadige konflik in Burundi. Deur middel van hierdie studie kan ‘n duidelike opsomming gemaak word dat daar inderdaad ‘n positiewe korrelasie tussen hierdie magte voorkom, waar die waardes van die onafhanklike veranderlike (toegang tot grond en bevolkingsgroei) geassosieer word met die waardes van die afhanklike veranderlike (geweldadige konflik). Hierdie korrelasie verg dus ‘n beroep om erkenning te gee aan die kompleksiteit van konflik in Burundi. Hierdie etniese debat, wat tans die oorheersende konflik aanvuur, is maar net een van die verskeie interpretasies van sosiale breekpunte in Burundi is.
92

Estimated Extent and Fate of Chlorinated Solvent Contamination in the Soil of the Naval Air Station, Dallas, Texas

Trescott, Jill V. (Jill Virginia) 08 1900 (has links)
This thesis estimates the spatial extent of chlorinated solvent contamination of the soil at the Naval Air Station, Dallas, then estimates the fate and transport of these contaminants, over time, using the Soil Transport and Fate database and the Vadose-Zone Interactive Processes (VIP) modeling software. Geostatistical analysis identifies two areas with serious chlorinated solvent contamination. Fate and transport modeling estimates that this contamination will degrade and disperse from the soil phase to below regulatory limits within one year, although there is a risk of groundwater contamination. Contaminants are estimated to persist in the water and air phases of the soil. Further sampling is recommended to confirm the results of this study.
93

Identifying Cultural and Non-cultural Factors Affecting Litter Patterns in Hickory Creek, Texas

Carpenter, Evan S. 08 1900 (has links)
Plastic deposition in hydrological systems is a pervasive problem at all geographic scales from loci of pollution to global ocean circulation. Much attention has been devoted to plastic deposition in marine contexts, but little is known about inputs of plastics into local hydrological systems, such as streams. Any attempt to prevent plastic litter must confront people’s behaviors, so archaeological concepts are used to distinguish between various cultural inputs (e.g., littering) and non-cultural forces (e.g., stream transport) that affect litter patterns on the landscape. Litter surveys along Hickory Creek in Denton, TX, are used to assess these factors.
94

Spatial Analysis of Atrazine in the Elm Fork Watershed

Ochandio, Mario Roberto 05 1900 (has links)
This study assessed the water quality of the Elm Fork Watershed with regards to the herbicide Atrazine. Atrazine is a potential environmental endocrine disruptor and carcinogen. Overall, concentrations were lower than the four-quarter drinking water average of 3 µg/Lthe Maximum Contaminant Level set by the USEPA. However, three creek stations had four-quarter average concentrations greater than 3 µg/L, and virtually all samples exceeded the 0.1 µg/L standard set in Europe [1,2]. Statistically significant differences in concentrations were detected between the 27 sampling stations and areas of high concentrations were identified. However correlations between Atrazine concentrations and land-use and precipitation were not statistically significant. Further analysis with more detailed data should be conducted before any relationships are discarded.
95

Integration of field-based analysis of plant community dynamics with quantitative analysis of landscape change in the Ray Roberts Lake area, 1987—1997

McDonough, Theresa J. 05 1900 (has links)
This study focused on the effectiveness of integrating traditional plant community analyses with landscape ecological analyses based on remotely sensed data. A temporal analysis of plant community diversity was conducted for major plant communities of the Ray Roberts Lake area using transect monitoring data collected between 1987 and 1997. Landscape analyses were performed with FRAGSTATS*ARC using classified SPOT satellite imagery for 1987 and 1997. Although the methodology developed in this work was exploratory, it was found that characterizing the dynamics of major plant communities in the study area produced a more effective and insightful analysis of Ray Roberts Lake area landscape dynamics.
96

Avaliação da susceptibilidade térmica e do efeito das condições ambientais no enrijecimento de misturas asfálticas densas à luz de seus comportamentos resilientes / Evaluation of the thermal susceptibility and the effect of the environmental conditions in the hardening of dense-graded hot-mix asphalt to the light of their resilient behavior

Gigante, Antonio Carlos 24 August 2007 (has links)
Este trabalho teve como objetivo avaliar o módulo de resiliência de misturas asfálticas densas sob duas condições. A primeira foi o estudo dos efeitos do enrijecimento de misturas asfálticas densas em condições ambientais diferentes (cinco condições) que são: AAAL (ao ar e à luz), AASL (ao ar e sem luz), AVAL (baixa pressão atmosférica e à luz), AVSL (baixa pressão atmosférica e sem luz) e CLIMA (ao clima e intempéries), tendo sido utilizados para este experimento CAP 20, centro da faixa C do DNER como distribuição granulométrica e preparados segundo a AASHTO PP2. Neste estudo concluiu-se que não houve efeito significativo da exposição da luz artificial nas condições AL e SL, assim como não houve, também, efeito significativo na variação do módulo de resiliência nas condições de exposição ou não ao ar (AV e AA); nas demais condições houve melhora significativa nos resultados. Na segunda parte foram avaliados os efeitos de alguns fatores na susceptibilidade térmica de misturas asfálticas densas: tipo de agregado (basalto, gabro e granito), tipo de asfalto (CAP 20 e CAP 40), teor de asfalto (5%, 5,5% e 6%), presença de aditivo (com e sem cal) e temperaturas de ensaio (10ºC, 25ºC e 40ºC). Todos os corpos-de-prova foram preparados segundo procedimento da AASHTO PP2. Na segunda parte do experimento, concluiu-se que o CAP 40 produziu valores médios de Vv superiores aos do CAP 20, as misturas com teor de 5,5% apresentaram maior resistência à tração a 25°C, o módulo de resiliência e a relação MR/RT diminuem com o aumento do teor de CAP. / This work intended to evaluate the resilient modulus of dense-graded hot-mix asphalt under two conditions. The first condition comprehends a study of the hardening effects of densegraded hot mix asphalt submitted to five environmental conditions: AAAL (air and artificial light), AASL (air and no artificial light), AVAL (low atmospheric pressure and artificial light), AVSL (low atmospheric pressure and no artificial light) and CLIMA (exposition to intemperism). In this phase, it was used an AC-20 asphalt binder and DNER middle band \"C\" as aggregate\'s particles size distribution. Specimens were prepared according to AASHTO PP2. Based on the results of the first part of the experiment, it was concluded that there was no significant effect of the artificial light exposition on AL and SL conditions, as well as on the variation of resilient modulus under air conditions (AV and AA). The other conditions presented better performance results. The second part of the experiment aimed to evaluating the effect of some factors in the thermal susceptibility of dense-graded HMA, that are: aggregate type (basalt, gabbro, granite), asphalt type (AC-20 and AC-40), binder content (5,0%, 5,5% and 6,0%), presence of additive (with or without lime) and test temperature (10ºC, 25ºC and 40ºC). As in the first part of the experiment, all specimens were prepared according to AASHTO PP2. Results of the second part of the experiment led to the following conclusions: mixtures using AC-40 showed average air voids higher than mixtures using AC-20, mixtures with a binder content of 5,5% showed the highest values of tensile strength, at 25°C, the resilient modulus and the MR/RT ratio reduce when binder content increases.
97

Post-fire Succession and Carbon Storage in the Northern Everglades

Unknown Date (has links)
Fire plays a key role in the ecology of the Everglades and is a ubiquitous tool for managing the structure, function, and ecosystem services of the Greater Everglades watershed. Decades of hydrologic modifications have led to the alteration of plant community composition and fire regime in much of the Everglades. To create a better understanding of post-fire recovery in sawgrass (Cladium jamaicense) communities, sawgrass marshes in the northern Everglades were studied along a chronosequence of time since fire and along a nutrient gradient. Areas closer to a water nutrient source and with fewer mean days dry contained greater total and dead aboveground graminoid biomass whereas live graminoid biomass was greater in areas with less time since fire and with fewer days dry. Post-fire characteristics of sawgrass marshes can provide insight on the effectiveness of fire management practices in the maintenance and restoration of quality habitat in the northern Everglades. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection
98

Examination of the Use of Floating Individuals of Halodule wrightii (Ascherson, 1868) for Restoration

Unknown Date (has links)
The goal of this study was to develop an alternative approach to typical seagrass transplantation techniques that damage the donor bed. Floating individuals of Halodule wrightii were collected in the Indian River Lagoon (IRL), Florida, during fall of 2013 and spring of 2014, with the fall collection planted in outdoor tanks. Only 25% of individuals collected in the fall survived the winter in the tanks. Individuals from both collections were deployed onto biodegradable mats in a capped dredge hole in the IRL in March, 2014. Approximately 66% of the mats survived the six-month experiment, and the area covered by seagrass quadrupled. Growth in shoot count, average height, horizontal spread, and biomass was similar for both fall and spring treatments. Thus, time and effort of overwintering had no benefit over spring harvesting. The use of floating individuals can provide a more practical, environmentally friendly alternative to traditional transplanting for seagrass re storation. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection
99

Integration of satellite images and census data for quality of life assessment in Hong Kong.

January 2002 (has links)
Ip Oi-ching. / Thesis submitted in: October 2001. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 142-152). / Abstracts in English and Chinese. / LIST OF ABBREVIATIONS --- p.ix / LIST OF TABLES --- p.xiv / LIST OF FIGURES --- p.xviii / LIST OF APPENDICES --- p.xxii / Chapter CHAPTER ONE --- INTRODUCTION / Chapter 1.1 --- Conceptual Framework --- p.1 / Chapter 1.2 --- Objectives --- p.4 / Chapter 1.3 --- Significance --- p.5 / Chapter 1.4 --- Study Area --- p.6 / Chapter 1.5 --- Organization Of Thesis --- p.8 / Chapter CHAPTER TWO --- LITERATURE REVIEW / Chapter 2.1 --- Quality of Life and Indicators --- p.9 / Chapter 2.1.1 --- Scope of study for quality of life --- p.9 / Chapter 2.1.2 --- Development and evolution of quality of life studies --- p.13 / Chapter 2.1.3 --- Quality of life indicators --- p.14 / Chapter 2.2 --- Quality of Life Studies using Remote Sensing data --- p.17 / Chapter 2.2.1 --- Attributes derived from remote sensing --- p.17 / Chapter 2.2.2 --- Environmental changes and landuse change --- p.17 / Chapter 2.2.3 --- Housing quality --- p.18 / Chapter 2.2.4 --- Integration of remote sensing data and census data --- p.19 / Chapter 2.3 --- Quality of Life Study and Application of Remote Sensing in Hong Kong --- p.20 / Chapter 2.4 --- Summary --- p.22 / Chapter CHAPTER THREE --- METHODOLOGY / Chapter 3.1 --- Data Description --- p.24 / Chapter 3.1.1 --- Biophysical data --- p.24 / Chapter 3.1.2 --- Socioeconomic indices --- p.28 / Chapter 3.1.3 --- Data extracted at Tertiary Planning Unit --- p.30 / Chapter 3.2 --- Satellite Data Preprocessing --- p.32 / Chapter 3.2.1 --- Radiometric and atmospheric correction --- p.38 / Chapter 3.2.2 --- Image normalization --- p.43 / Chapter 3.2.3 --- Geometric correction --- p.44 / Chapter 3.3 --- Landuse and Land-cover Classification --- p.45 / Chapter 3.4 --- Spectral Data Extraction and Transformation --- p.47 / Chapter 3.5 --- Integration of Spectral and Census Data for Quality of Life Modeling --- p.49 / Chapter 3.5.1 --- Inter-relationship between biophysical data and socioeconomic data --- p.50 / Chapter 3.5.2 --- Integrated quality of life modeling --- p.50 / Chapter 3.6 --- Summary --- p.51 / Chapter CHAPTER FOUR --- DATA DESCRIPTION / Chapter 4.1 --- Socioeconomic Data --- p.53 / Chapter 4.2 --- Spectral Data --- p.62 / Chapter 4.2.1 --- Raw data --- p.62 / Chapter 4.2.2 --- Landuse and land cover --- p.63 / Chapter 4.2.3 --- Vegetation indices --- p.66 / Chapter 4.2.4 --- Tasseled cap components --- p.67 / Chapter 4.2.5 --- Surface temperature --- p.69 / Chapter 4.2.6 --- Principal components extracted from biophysical variables --- p.70 / Chapter 4.3 --- Summary --- p.79 / Chapter CHAPTER FIVE --- INTERRELATIONSHIP BETWEEN SPECTRAL VARIABLES AND SOCIOECONOMIC VARIABLES / Chapter 5.1 --- Framework of Analysis --- p.82 / Chapter 5.2 --- Correlation among Socioeconomic and Biophysical data --- p.84 / Chapter 5.3 --- Stepwise Multiple Linear Regression Models --- p.91 / Chapter 5.3.1 --- Biophysical data as dependent variable --- p.91 / Chapter 5.3.1.1 --- NDVI as dependent variable --- p.95 / Chapter 5.3.1.2 --- URBANM as dependent variable --- p.98 / Chapter 5.3.2 --- Socioeconomic data as dependent variable --- p.101 / Chapter 5.3.2.1 --- POP´ؤDEN as dependent variable --- p.101 / Chapter 5.4 --- Summary and Discussion --- p.103 / Chapter CHAPTER SIX --- QUALITY OF LIFE ANALYSIS / Chapter 6.1 --- Indictors for Quality of Life Study --- p.105 / Chapter 6.2 --- QOL Indicators --- p.110 / Chapter 6.3 --- Spatial Variation of QOL --- p.114 / Chapter 6.4 --- Temporal Variation of QOL --- p.125 / Chapter 6.5 --- Summary and discussion --- p.131 / Chapter CHAPTER SEVEN --- CONCLUSION / Chapter 7.1 --- Summary of Findings --- p.134 / Chapter 7.1.1 --- Inter-relationship between socioeconomic and biophysical variables --- p.135 / Chapter 7.1.2 --- Quality of life indicators --- p.135 / Chapter 7.2 --- Limitations of the Study --- p.13 8 / Chapter 7.3 --- Recommendations for Further Studies --- p.140 / REFERENCES --- p.142 / APPENDIX A --- p.153 / APPENDIX B --- p.157 / APPENDIX C --- p.167
100

Framework for vacant land policy in shrinking cities

Culbertson, Kurt Douglas January 2018 (has links)
This thesis provides a theoretical framework for evaluating the causes of vacant land in shrinking cities. The focus of this thesis was New Orleans and St. Louis; these two cities were selected as the case studies because they are roughly of similar age, possess a common cultural and economic heritage, and have a geographic footprint which encompasses different environmental conditions. This thesis evaluated factors that contribute to patterns of land vacancy within these two cities. Factors included in this evaluation include employment and other economic and cultural opportunities, environmental and ecological conditions, social dynamics and conditions, governmental management decisions, and 'quality of life' stressors, such as proximity to major infrastructure and industrial development. The theoretical framework described in this thesis is intended to apply to other shrinking cities beyond the case studies. A geographic information system database using historical maps and population census data were created for each city and utilized to examine temporal patterns in the relationship between land vacancy and a variety of environmental, economic, and social factors. Maps from the time of the founding of each city were geo-referenced to create a depiction of the ecological conditions prior to European settlement at the sites of New Orleans in 1718 and St. Louis in 1764, respectively. Time-series data gathered from the United States population censuses were utilized to document spatial change of the two cities as they evolved. Homo sapiens like other species compete for habitat. Access to high quality habitat within the urban ecosystem is determined by contestation between individuals and social groups, through market mechanisms and through management decisions, both utilitarian and ideological. Corruption and violence may also be factors. Individual agency is a factor in this contestation but social and cultural structures can also work to limit individual choices, particularly for minorities and low income residents, and relegate many residents to suboptimum or marginal habitat. A data analysis of both New Orleans and St. Louis showed that the quantity and location of vacant land is primarily influenced by proximity to opportunities and by proximity to major risks which impact the quality of Homo sapiens habitat. The first of these is proximity to opportunities such as employment, education, and cultural resources. The second is the presence of natural hazards, such as flooding and geological hazards, as revealed by the analysis of the historical ecology of the city. The third is the impact of local government management decisions and social planning which has spatial implications, including racially-based zoning, racial covenants, redlining, and isolation from public services and facilities such as the segregation of public schools. These decisions are often the reflection of ideology and power relationships. A fourth driver of land vacancy is proximity to risks, notably industrial lands, but also the intrusion of major infrastructure projects such as the development of the railyards and rail corridor of St. Louis, the construction of the Industrial Canal in New Orleans, and the construction of Interstate highways through both cities. In some circumstances, such drivers that include the unintended consequences of utilitarian decisions. The fifth driver include socio-economic factors and the neighborhood effects of crime, and poor education. These five drivers act in different proportions in each city to influence land values which, in turn, drive levels of vacancy. This comparative investigation revealed that the impact of geophysical factors on land vacancy varies greatly between New Orleans and St. Louis. While much of New Orleans lies below sea level and is often subject to flooding and hurricanes, little of the vacant lands of St. Louis are impacted by geophysical factors. In contrast, management decisions and social planning have contributed significantly to the concentration of poverty and, in turn, land vacancy in both cities. While some of these management decisions are utilitarian in nature and intended to provide the greatest benefits for the most number of people, others are ideologically driven or reflect power relationships and in the case of both New Orleans and St. Louis, racism. Proximity to risks, such as active railroad tracks, major highways, and industrial development, also has a strong relationship to land vacancy in both cities. Land vacancy also has a strong spatial relationship with areas of low income, poor education, and crime and neighborhood effects. While an understanding of environmental history can provide a useful guide to vacant land policy, efforts to address the challenge of vacant lands must consider not only the symptoms but the underlying causes of vacancy, particularly economic and social factors. This thesis is addressed to planners, architects, urban designers, landscape architects, and elected and appointed government officials who work to address the challenges of shrinking cities. Though this thesis examined the causes of vacant land in two shrinking cities, future research should examine the application of the theoretical framework presented here to cities experiencing growth as well.

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