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  Partner: UNT Libraries
 Department: Department of Geography
 Collection: UNT Theses and Dissertations
Automated Treetop Detection and Tree Crown Identification Using Discrete-return Lidar Data

Automated Treetop Detection and Tree Crown Identification Using Discrete-return Lidar Data

Date: May 2013
Creator: Liu, Haijian
Description: Accurate estimates of tree and forest biomass are essential for a wide range of applications. Automated treetop detection and tree crown discrimination using LiDAR data can greatly facilitate forest biomass estimation. Previous work has focused on homogenous or single-species forests, while few studies have focused on mixed forests. In this study, a new method for treetop detection is proposed in which the treetop is the cluster center of selected points rather than the highest point. Based on treetop detection, tree crowns are discriminated through comparison of three-dimensional shape signatures. The methods are first tested using simulated LiDAR point clouds for trees, and then applied to real LiDAR data from the Soquel Demonstration State Forest, California, USA. Results from both simulated and real LiDAR data show that the proposed method has great potential for effective detection of treetops and discrimination of tree crowns.
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Quantitative Comparison of Lidar Data and User-generated Three-dimensional Building Models From Google Building Maker

Quantitative Comparison of Lidar Data and User-generated Three-dimensional Building Models From Google Building Maker

Date: August 2012
Creator: Liu, Yang
Description: Volunteered geographic information (VGI) has received increased attention as a new paradigm for geographic information production, while light detection and ranging (LiDAR) data is widely applied to many fields. This study quantitatively compares LiDAR data and user-generated 3D building models created using Google Building Maker, and investigate the potential applications of the quantitative measures in support of rapid disaster damage assessment. User-generated 3D building models from Google Building Maker are compared with LiDAR-derived building models using 3D shape signatures. Eighteen 3D building models are created in Fremont, California using the Google Building Maker, and six shape functions (distance, angle, area, volume, slope, and aspect) are applied to the 18 LiDAR-derived building models and user-generated ones. A special case regarding the comparison between LiDAR data and building models with indented walls is also discussed. Based on the results, several conclusions are drawn, and limitations that require further study are also discussed.
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Shoreline Erosion at Mad Island Marsh Preserve, Matagorda County, Texas

Shoreline Erosion at Mad Island Marsh Preserve, Matagorda County, Texas

Date: August 2005
Creator: Mangham, Webster
Description: The Nature Conservancy of Texas (TNC) is concerned with the amount of shoreline erosion taking place at its Mad Island Marsh Preserve (MIMP), located in Matagorda Bay, Texas. The MIMP is a 7,100 acre nature preserve that borders the Gulf Intracoastal Waterway and is eroded by waves generated by barge traffic. TNC is concerned that erosion will shorten Mad Island Bayou which may increase the salinity of Mad Island Lake; with detrimental effects on lake and marsh habitats. This study uses GPS technology to map the current shoreline and GIS to determine ten year erosion rates (1995 - 2005). Results show that erosion is occurring at various rates along the shoreline as well as along the oxbow bend in Mad Island Bayou.
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Geology as a Georegional Influence on Quercus Fagaceae Distribution in Denton and Coke Counties of Central and North Central Texas and Choctaw County of Southeastern Oklahoma, Using GIS as an Analytical Tool.

Geology as a Georegional Influence on Quercus Fagaceae Distribution in Denton and Coke Counties of Central and North Central Texas and Choctaw County of Southeastern Oklahoma, Using GIS as an Analytical Tool.

Date: December 2007
Creator: Maxey, George F.
Description: This study elucidates the underlying relationships for the distribution of oak landcover on bedrock and soil orders in two counties in Texas and one in Oklahoma. ESRI's ArcGis and ArcMap was used to create surface maps for Denton and Coke Counties, Texas and Choctaw County, Oklahoma. Attribute tables generated in GIS were exported into a spreadsheet software program and frequency tables were created for every formation and soil order in the tri-county research area. The results were both a visual and numeric distribution of oaks in the transition area between the eastern hardwood forests and the Great Plains. Oak distributions are changing on this transition area of the South Central Plains. The sandy Woodbine and Antlers formations traditionally associated with the largest oak distribution are carrying oak coverage of approximately 31-32% in Choctaw and Denton Counties. The calcareous Blackland and Grand Prairies are traditionally associated with treeless grasslands, but are now carrying oak and other tree landcover up to 18.9%. Human intervention, including the establishment of artificial, political and social boundaries, urbanization, farming and fire control have altered the natural distribution of oaks and other landcover of this unique georegion.
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Water systems, water policy, and Karst terrain: An analysis of the complex relationships between geology, economy, public perceptions, and policy in southern Trelawny, Jamaica.

Water systems, water policy, and Karst terrain: An analysis of the complex relationships between geology, economy, public perceptions, and policy in southern Trelawny, Jamaica.

Access: Use of this item is restricted to the UNT Community.
Date: December 2005
Creator: McCall, Sarah
Description: Jamaica has an abundance of freshwater resources, however, a lack of infrastructure makes treated, piped water inaccessible in many areas. Through literature reviews and site visits, this thesis is an analysis of how the people and land, and money and policy, interact with one another in relation to Jamaica's freshwater resources and water infrastructure. Special attention is given to the island's type-example Cockpit karst geology; tourism, mining, and farming's relation to this karst; types of water delivery systems in rural southern Trelawny's Cockpit Country; southern Trelawny residents' perceptions of the water situation; and policy and development goals in the context of Jamaica and southern Trelawny. I hope to bring attention to the unique social, geologic, and developmental context of water in Jamaica, and more specifically to garner attention for major water infrastructure improvements in south Trelawny. A number of recommendations for improvements with policy and infrastructure are made.
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Gracias a La Nacionalización De Los Hidrocarburos: a Critical Analysis of Bolivia’s Transition to Compressed Natural Gas

Gracias a La Nacionalización De Los Hidrocarburos: a Critical Analysis of Bolivia’s Transition to Compressed Natural Gas

Date: May 2015
Creator: McCollum, Jerl Levi
Description: This paper critically analyzes the implementation of compressed natural gas and the ways in which it creates discourse in urban Bolivia. The rapidly developing nation is keen on making ubiquitous use of compressed natural gas a reality by issuing subsidies, citing increased mobility, savings, and environmental stewardship as the primary motives. Currently, eight out of every 10 public vehicles in Bolivia are powered by compressed natural gas. Through semi-structured interviews, questionnaires and secondary data collection, this paper elucidates the transitional process of building a natural gas-based transport network through discursive governance. This work draws on the critical discourse analysis literature to dissect disaggregated modal preference data, government documents, and news articles collected in Santa Cruz, Latin America's second fastest growing city. Moreover, this paper identifies and examines the ways in which the counter-discourse impacts the transformation of the country’s energy matrix. Results show that Bolivian automobile owners are reluctant to convert their automobiles, despite reduced transportation costs, stating that minimal compressed natural gas infrastructure exists outside of urban areas, and the conversion damages their vehicles’ motor. Additionally, the research reveals that automobile owners are currently the main beneficiaries, though respondents who do not posses an automobile speak more favorably of ...
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"A Tale of Two Weapons": Late Holocene Hunting Technology in North Central Texas

"A Tale of Two Weapons": Late Holocene Hunting Technology in North Central Texas

Date: May 2009
Creator: Miller, Mickey Joe
Description: This research is an investigation of the Late Holocene technological transition from the spearthrower and dart to the bow and arrow in north central Texas. It is conducted through a theoretical approach that utilizes ethnographic research, experimental archaeology and the archaeological record to elucidate differences in the behaviors and hunting strategies of Late Archaic and Late Prehistoric groups. It first confirms that there was a transition. Second, a lithic analysis demonstrates that there are fundamental differences in the sizes of the stone dart and arrow points that relate to the propulsive requirements of the weapon systems. Third, it is shown these size differences constrain maintenance potentials and that indeed dart and arrow points exhibit stark differences in their life histories in spite of being employed for the same task. And finally, the faunal record suggests that this transition was associated with an increase in foraging efficiency.
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Neural Tube Defect, Heart Defect, Oral Cleft and Their Geospatial Associations with Supermarket and Convenience Stores in the City of Dallas, Texas

Neural Tube Defect, Heart Defect, Oral Cleft and Their Geospatial Associations with Supermarket and Convenience Stores in the City of Dallas, Texas

Date: August 2013
Creator: Miyakado, Haruna
Description: Birth defects are the leading cause of infant death in the United States. Research has linked poor maternal micronutrient intake to birth defects including neural tube defects, heart defects, and oral clefts. After investigating spatial patterns of these birth defects in the City of Dallas and the neighborhood characteristics within clusters, geospatial access to supermarkets and convenience stores measured by proximity and concentrations are examined as environmental risk factors for nutrition-related birth defects. Spatial clusters of all three nutrition-related birth defects exist in the City of Dallas. Cluster for NTD occurs in vulnerable places with lower income and high minority population specifically Hispanics with no supermarkets. Cluster for heart defects mostly occurs in high income and predominantly white neighborhoods with many supermarkets. Clusters of oral clefts mostly occurs in middle-class income with relatively high minority populations with many convenience stores. For the entire study area, geographical access to supermarkets that include healthy foods are shown to be spatially reachable from most of mothers of infants with nutrition-related birth defects as well as convenience stores that typically include the majority of unhealthy processed foods with very few nutrients. Thus, not only easy geographical access to healthy food vendors but to convenience ...
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Gis, Modeling And Human Civilization: The Birth Of Geo-social Engineering

Gis, Modeling And Human Civilization: The Birth Of Geo-social Engineering

Date: December 2011
Creator: Morris, E. Scott
Description: Computer-based, mathematical models have significant value in describing the processes behind urban development and its inhabitants. The following research describes the theories and concepts behind modeling and offers insight into the potential future of the field. First, the research covers a brief history of applicable modeling strategies. This is followed by a summary of current popular approaches. The numerical background of geo-social engineering is developed through mathematical techniques. Geo-social engineering is the integration of modeling into the basic design human civilization. The mathematical models will be incorporated into a design of a computer program. From this, a possible geo-social model structure is presented and its architecture is described.
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An environmental justice assessment of the light rail expansion in Denton County, Texas.

An environmental justice assessment of the light rail expansion in Denton County, Texas.

Date: August 2007
Creator: Moynihan, Colleen T.
Description: This study analyzes the proposed passenger rail line expansion along US Interstate Highway 35 in Denton County, Texas. A multi-dimensional approach was used to investigate potential environmental justice (EJ) consequences from the expansion of the transportation corridor. This study used empirical and historical evidence to identify and prioritize sites for potential EJ concerns. Citizen participation in the decision making process was also evaluated. The findings of this research suggest that the southeast Denton community has the highest potential for environmental justice concerns. This study concludes by offering suggestions for an effective public participation process. These include the incorporation of a community's local history into an environmental justice assessment, and tailoring the public planning process to the demographics and culture of the residents.
Contributing Partner: UNT Libraries