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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.
101

Flood Risk Perception in Tanzania : A Case of Flood Affected Arean in Dar es Salaam

Fintling, Carolina January 2006 (has links)
The main objective of this study is to understand and asses flood risk perception among people living in Msimbazi Valley in Das es Salaam, Tanzania. Many of the people I have interviewed are experiencing flooding every year but it is rarely considered disastrous. Looked at individually they may not be disasters but cumulatively they may be. The rapid urbanisation, in this part of the world, forces people to live on hazardous but central land because of the livelihood opportunities available there. The government and the local communities are well aware of the risk of floods in the area and are considered as a serious threat to the families. People are still living in these areas because they find the benefits big enough to make up the risks.
102

Comparing Vegetation Cover in the Santee Experimental Forest, South Carolina (USA), Before and After Hurricane Hugo: 1989-2011

Cosentino, Giovanni R 03 May 2013 (has links)
Hurricane Hugo struck the coast of South Carolina on September 21, 1989 as a category 4 hurricane on the Saffir-Simpson Scale. Landsat Thematic mapper was utilized to determine the extent of damage experienced at the Santee Experimental Forest (SEF) (a part of Francis Marion National Forest) in South Carolina. Normalized Difference Vegetation Index (NDVI) and the change detection techniques were used to determine initial forest damage and to monitor the recovery over a 22-year period following Hurricane Hugo. According to the results from the NDVI analysis the SEF made a full recovery after a 10-year period. The remote sensing techniques used were effective in identifying the damage as well as the recovery.
103

Influence of lakes and peatlands on groundwater contribution to Boreal streamflow

2013 March 1900 (has links)
How much groundwater flows to boreal streams depends on the relative contributions from each landscape unit (forested uplands, lakes, and peatlands) within a catchment along with its hydrogeologic setting. Although there is an understanding of the hydrologic processes that regulate groundwater outputs from individual landscape units to their underlying aquifers (both coarse- and fine-textured) in the boreal forest, less understood is how the topography, typology, and topology (i.e. hydrologic connectivity) of the landscape units regulates groundwater flow to streams. Improved understanding of groundwater-stream interactions in the Boreal Plain of Alberta and Saskatchewan is critical as this region is undergoing substantial environmental change from land cover disturbances for energy and forestry industries and climate change. This thesis determines groundwater-stream interactions during the autumn low-flow period in a 97 km2 glacial outwash sub-catchment of White Gull Creek Research Basin, Boreal Ecosystem Research and Modelling Site, Saskatchewan. The catchment (Pine Fen Creek) is comprised of a large (30 km2) valley-bottom peatland, two lakes, and jack pine (Pinus banksiana) uplands. The pine uplands are important areas of annual groundwater recharge for the catchment. Vertical hydraulic gradients (VHGs) show frequent flow reversals between the lakes and sand aquifer, and spatially diverse VHGs between the peatland and sand aquifer. Groundwater flow nets and lateral hydraulic gradients indicate the stream receives groundwater along its length. Isotopic samples of end members corroborate the hydrometric data. Catchment streamflow response during the 2011 low flow period was not simply the addition of net groundwater inputs from each landscape unit. Instead, the large size, valley-bottom position, and short water ‘memory’ of the peatland were the critical factors in regulation of catchment streamflow during low flow periods. Peatland hydrologic function alternated between a source and sink of runoff (surface and subsurface) to the stream, dependent on the position of the water table; a value of 0.15 m below peat surface was the critical functional tipping point. Given the high percentage of peatlands (21%) within the Boreal Plain, incorporating their runoff threshold is required in parameterizing runoff generation in hydrological models, and thus predicting impacts of peatland degradation and forest clearing on streamflow.
104

Enhancing Dependency Pair Method using Strong Computability in Simply-Typed Term Rewriting

草刈, 圭一朗, Kusakari, Keiichirou, 酒井, 正彦, Sakai, Masahiko January 2007 (has links)
No description available.
105

Population Dynamics of Plain Chachalacas in the Lower Rio Grande Valley

Gandaria, Adan G. 2009 December 1900 (has links)
The Lower Rio Grande Valley (LRGV) of Texas is an ecologically diverse region in the United States and marks the northernmost extension for many tropical species of plants and animals. Since the early 1900s, 95% of the native Tamaulipan brushlands have been cleared due to agricultural practices and urban development. The plain chachalaca (Ortalis vetula) is a medium sized bird endemic to the native brushlands of the LRGV. In 2003, I trapped and radio-tagged 29 birds (16 males, 13 females) to evaluate the effects of fragmentation on the population dynamics (i.e., survival, mortality, and movements) of this brushland species. My study objectives were to estimate (1) seasonal survival of chachalacas by sex, and (2) ranges, core areas, and movements using radio telemetry. Mammalian predation (43%, n = 6) and unknown (43%, n = 6) deaths accounted for the majority of mortality observed. I found no difference (P > 0.05) in estimated 8-month survival (December 2003-July 2004) between males (S = 0.364, SE = 0.132) and females (S = 0.405, SE = 0.153). In comparing seasonal survival for all birds (males and females combined), I observed a difference (P < 0.05) in survival between the nesting (S = 0.414, SE = 0.103) and breeding seasons (S = 0.917, SE = 0.079). Female ranges (x‾ = 117 ha, range = 42–177 ha) and core areas (x‾ = 23 ha, range = 5–46 ha) during the nesting season were larger than male ranges (x‾ = 41 ha, range = 31–46 ha) and core areas (x‾ =10 ha, range = 7–14 ha) during the same period. During the breeding season, female ranges (x‾ = 59 ha, range = 10–188 ha) and core areas (x‾ = 9 ha, range = 2–33 ha) were similar to male ranges (x‾ = 48 ha, range = 4–130 ha) and core areas (x‾ = 9 ha, range = 1–23 ha). Mean distances between seasons were similar for both sexes (females, nesting, x‾ = 486, breeding, x‾ = 345; males, nesting, x‾ = 184, breeding, x‾ = 292), though females distances generally were greater. Dispersal defined as movement off the Santa Ana National Wildlife Refuge was observed for 3 birds. In 2 cases, a radio-tagged female and male were observed crossing the Rio Grande River (approximately 100-m wide) to habitat in Mexico. Study results suggested mammalian predation may limit the growth of chachalaca populations. Though land use changes such as agricultural uses may not directly limit chachalaca populations in providing cover and food, concentration of populations in remnant native brushlands may serve as ecological “sinks” to the species. Greater range and movement data observed in my study may be attributed to suboptimal habitat (i.e., increased fragmentation) for plain chachalacas.
106

The Ethnobotany Of Wild Food Plant Use In The Konya Basin: A Quantitative And Ethnoarchaeological Approach

Erkal Tsetsekos, Aylan 01 September 2006 (has links) (PDF)
In this ethnobotanical study, an ethnoarchaeological approach was adopted for the archaeological implications of the importance of wild food plants and their dietary uses in the Neolithic and Chalcolithic Periods in Central Anatolia by exploring the dietary uses of these plants by the modern villagers of Konya Basin. The study was based on the indigenous knowledge of the modern villagers of Konya of managing wild food plant resource in their surroundings for the dietary uses. This knowledge was explored through ethnobotanical research strategies. The study was limited by both the research subject and the area for a better focus on the research. The geographical borders were limited to Central Anatolia as it included Neolithic and Chalcolithic sites with detailed archaeological investigations and it made a comparison available between different geographical zones. Because it was possible to study similar environments today in the Konya Basin, nine modern villages to collect ethnobotanical data were chosen from three different environmental zones in this area, which included wetland, forest and steppe zones. The wild fruit, nut and tuber species recovered from the archaeological excavations were selected for study in their current natural environments. The different strategies of harvesting, processing and storage local people used for the consumption of each plant species provided useful implications to archaeological recoveries.
107

Groundwater Vulnerability Assessment With Drastic Method:a Case-study On Kirikkale Plain, Turkey

Buyukdemirci, Hakan Ahmet 01 May 2012 (has links) (PDF)
The objective of this study is to achieve vulnerability assessment of the groundwater by using DRASTIC Method which is developed by United States Environmental Protection Agency (USEPA). It is most commonly used overlay and index method all over the world. Evaluation of groundwater vulnerability would be performed by using computer programs which are based on Geographical Information System (GIS) in order to facilitate data management and spatial analysis. The term vulnerability, that is used in this study, could be defined as a degree of capacity of the geological settings which are above water table, cause as joining of contaminants to groundwater where imposed by environmental factors. All the groundwater has some degree of protection under natural condition. It is an important initial step to identify degree of vulnerability by an index which is provided by superimposition of the environmental and geological properties that are explained in DRASTIC Method. v At the end of the study by using a computer program together with DRASTIC Method a vulnerability map will be obtained. The vulnerability map is an informative tool from different aspects such as it is an initial step for taking an attention of risk of groundwater could be getting polluted in some areas. In addition, surface activities could be limited by focusing on groundwater protection strategies which are considering degree of vulnerability of areas that are delineated by DRASTIC vulnerability index. With the purpose of groundwater vulnerability assessment Kirikkale Plain is selected for a study area. Because of inappropriate management of the industrial and domestic wastes, lack of waste water treatment plants and uncontrolled agricultural activities cause this region proned to groundwater pollution. At the end of this study a groundwater vulnerability map of the Kirikkale Plain is obtained and attention is drawn to the places which are more vulnerable are pointed out.
108

FUNDAMENTAL AND CLINICAL EVALUATION OF CHEST COMPUTED TOMOGRAPHY IMAGING IN DETECTABILITY OF PULMONARY NODULE

ISHIGAKI, TAKEO, HIROSE, MITSUHIKO, NAKAMURA, KIYOKO, IKEDA, MITSURU, ITO, KENGO, MILLA, NICOLAS 26 December 1994 (has links)
No description available.
109

The Study of a Novel Structure of Woven Continuous Carbon Fiber with High Electromagnetic Shieling

Hung, Wen-Chi 27 June 2003 (has links)
We study a novel structure employing the woven continuous carbon fiber (CCF) epoxy composite with high electromagnetic (EM) shielding. The influences of wove type, number and angle of overlapped plates upon the shielding effectiveness (SE) of wove CCF epoxy composite are investigated. The minimum SE of the single, double, and triple plain or balanced twill woven CCF composite plates were measured to be as high as 50 dB, 60 dB, and 70 dB, respectively. More than 100 dB of SE was obtained for the triple overlapped plain wove CCF composite at frequency of 0.9 GHz. The weight percentage of single CCF composite plate required for electronic application was 4.8% only, which was less than one quarter of the carbon fiber (CF) content and the performance of SE was 10 dB higher in comparison with long CF filled liquid crystal polymer composites. The SE calculated theoretically is consistent with that measured by the experiment. We have demonstrated a new woven CCF epoxy composite with high EM shielding. This work may lead to the development of effective shielding for plastic optical transceiver modules to prevent electromagnetic interference (EMI) for use in low cost and lightwave communication systems.
110

The archaeology and mobility at 10-CN-05, an archaeological site, Middle Snake River, Idaho /

Jacobs, Tedd D. January 2009 (has links)
Thesis (M.A.)--Boise State University, 2009. / Includes abstract. Includes bibliographical references (leaves 57-60).

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