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Public Transit Equity Analysis At Metropolitan And Local Scales: A Focus On Nine Large Cities In The Us, Greg P. Griffin, Ipek N. Sener 2016 Texas A&M Transportation Institute

Public Transit Equity Analysis At Metropolitan And Local Scales: A Focus On Nine Large Cities In The Us, Greg P. Griffin, Ipek N. Sener

Journal of Public Transportation

Recent studies on transit service through an equity lens have captured broad trends from the literature and national-level data or analyzed disaggregate data at the local level. This study integrates these methods by employing a geostatistical analysis of new transit access and income data compilations from the Environmental Protection Agency. By using a national data set, this study demonstrates a method for income-based transit equity analysis and provides results spanning nine large auto-oriented cities in the US. Results demonstrate variability among cities’ transit services to low-income populations, with differing results when viewed at the regional and local levels. Regional-level analysis ...


Topic Modeling And The Historical Geography Of Scotland, Michael Gavin, Eric Gidal 2016 University of South Carolina

Topic Modeling And The Historical Geography Of Scotland, Michael Gavin, Eric Gidal

Studies in Scottish Literature

Presents selected findings from a larger project using topic modeling for clusters of keywords from a defined corpus of 18th and 19th century Scottish topographical sources (including the Old and New Statistical Surveys), linked to GIS mapping, to explore such topics as Scottish industry, transport, antiquities, print culture, and religion, with 10 maps included in the article text.


Gogeomatics And Its New London Ontario Group, Chunhua Liao, Hongyu Zhang, Peter Crawford 2016 Western University

Gogeomatics And Its New London Ontario Group, Chunhua Liao, Hongyu Zhang, Peter Crawford

GIS Day

GoGeomatics Canada is an online career network for the Canadian geomatics community. Founded in 2005, the website provides job postings, events listings, magazine articles and newsletter services for geomatics professionals. Informal and free monthly networking events at pubs across Canada are happening in more than ten regions including Ottawa, Toronto, Niagara, Calgary, Vancouver, and Edmonton. In October 2016, a new GoGeomatics London chapter was founded by a group of graduate students from the Department of Geography at Western University to bring social and career development events to the local geospatial community. The first event was held on Oct. 25 at ...


Use Of Drones And Gis To Identify Geoglyphs In The Sihuas Valley, Peru, Felipe Gonzalez-Macqueen 2016 Western University

Use Of Drones And Gis To Identify Geoglyphs In The Sihuas Valley, Peru, Felipe Gonzalez-Macqueen

GIS Day

Geoglyphs are anthropogenic features built onto the landscape by either removing a layer from the ground to expose the soil underneath or adding layers on top to create a relief. The most well-known examples of this are in the Nazca Valley, Peru where features can measure up to 400m long and have a variety of shapes. However not all geoglyphs are as big and complex as these, as is the case of the Sihuas Valley, Peru where geoglyphs are smaller and less elaborate in comparison. To identify and map these geoglyphs and other features, we used a combination of satellite ...


Examining The Community Food Environments For Elementary School-Aged Children In The City Of London And Middlesex County, Ontario, Catherine DuBreck 2016 Western University

Examining The Community Food Environments For Elementary School-Aged Children In The City Of London And Middlesex County, Ontario, Catherine Dubreck

GIS Day

Childhood obesity is a growing public health issue of global importance. In Canada, one in four children and youth are overweight or obese. Research suggests diet plays a crucial role in childhood obesity, and that prevalence rates of overweight or obesity among children in a neighborhood may relate to area socioeconomic characteristics and other environmental factors. The community nutrition environment (e.g., the type, location, and accessibility of food outlets) and the consumer nutrition environment (e.g., the price, promotion, placement, and availability of healthy options and nutrition information) can influence dietary habits, including the specific meal a child orders ...


A Gis Analysis Of Waulsortian-Like Mounds In The Mississippian Of Kentucky And Tennessee, Philip Roberson 2016 Murray State University

A Gis Analysis Of Waulsortian-Like Mounds In The Mississippian Of Kentucky And Tennessee, Philip Roberson

Scholars Week

Following a mass extinction nearly 365 million years ago, bryozoans and crinoids replaced corals and stromatoporoids as the dominant framework organisms in reefs and, during the very earliest part of the Carboniferous period, they built reef-like structures that are known from Europe, North America and Africa. They are characterized by large size, a matrix of carbonate mud, and their major framework organisms.

Waulsortian-like mounds occur in geographically isolated patches in outcrop and in the subsurface of central Tennessee and Kentucky where they are associated with hydrocarbon production. These mounds have the same characteristic organisms as the European mounds and do ...


Adoption Statistics Analysis Using Geographic Information Systems, Ashtan H. Williams 2016 Murray State University

Adoption Statistics Analysis Using Geographic Information Systems, Ashtan H. Williams

Scholars Week

This project highlights the use of Geographic Information Systems (GIS) for non-locational data by displaying adoption statistics. All topics displayed according to a political boundary (state or country) to include percentage of population awaiting adoption, time from termination of parental rights to finalization of adoption. A GIS-based analysis conducted for this project compares the cost of adoption from within the United States international. There is a focus on types of adoptions like special needs and race specific to provide an overall understanding of adoption in hopes to raise awareness.


Agbufferbuilder: A Geographic Information System (Gis) Tool For Precision Design And Performance Assessment Of Filter Strips, Mike G. Dosskey, Surendran Neelakantan, Tom G. Mueller, Todd Kellerman, Matt J. Helmers, Eduardo Rienzi 2016 United States Forest Service

Agbufferbuilder: A Geographic Information System (Gis) Tool For Precision Design And Performance Assessment Of Filter Strips, Mike G. Dosskey, Surendran Neelakantan, Tom G. Mueller, Todd Kellerman, Matt J. Helmers, Eduardo Rienzi

Matthew J. Helmers

Spatially nonuniform runoff reduces the water quality performance of constant-width filter strips. A geographic information system (GIS)-based tool was developed and tested that employs terrain analysis to account for spatially nonuniform runoff and produce more effective filter strip designs. The computer program, AgBufferBuilder, runs with ArcGIS versions 10.0 and 10.1 (Esri, Redlands, California) and uses digital elevation models to identify detailed spatial patterns of overland runoff to field margins. The tool then sizes filter dimensions according to those patterns using buffer area ratio relationships. The resulting design is larger along segments where more runoff flows and smaller ...


Open Access Geospatial Data, Hannah Hamalainen 2016 University of New Hampshire - Main Campus

Open Access Geospatial Data, Hannah Hamalainen

Open Access Week

The landscape of open-access geospatial data is vastly growing with an abundance of open source software, websites, and datasets available to the public. How do we find and access these resources? Find out from the Geospatial Services Center.


Spatial And Seasonal Responses Of Precipitation In The Ganges And Brahmaputra River Basins To Enso And Indian Ocean Dipole Modes: Implications For Flooding And Drought, M. S. Pervez, G. M. Henebry 2016 South Dakota State University

Spatial And Seasonal Responses Of Precipitation In The Ganges And Brahmaputra River Basins To Enso And Indian Ocean Dipole Modes: Implications For Flooding And Drought, M. S. Pervez, G. M. Henebry

Geoffrey Henebry

We evaluated the spatial and seasonal responses of precipitation in the Ganges and Brahmaputra basins as modulated by the El Niño Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) modes using Global Precipitation Climatology Centre (GPCC) full data reanalysis of monthly global land-surface precipitation data from 1901 to 2010 with a spatial resolution of 0.5° × 0.5°. The GPCC monthly total precipitation climatology targeting the period 1951–2000 was used to compute gridded monthly anomalies for the entire time period. The gridded monthly anomalies were averaged for the years influenced by combinations of climate modes. Occurrences of El Niño ...


Evapotranspiration In The Nile Basin: Identifying Dynamics, Trends, And Drivers 2002-2011, H. Alemu, A. T. Kaptué, G. B. Senay, M. C. Wimberly, Geoffrey Henebry 2016 South Dakota State University

Evapotranspiration In The Nile Basin: Identifying Dynamics, Trends, And Drivers 2002-2011, H. Alemu, A. T. Kaptué, G. B. Senay, M. C. Wimberly, Geoffrey Henebry

Geoffrey Henebry

Analysis of the relationship between evapotranspiration (ET) and its natural and anthropogenic drivers is critical in water-limited basins such as the Nile. The spatiotemporal relationships of ET with rainfall and vegetation dynamics in the Nile Basin during 2002–2011 were analyzed using satellite-derived data. Non-parametric statistics were used to quantify ET-rainfall interactions and trends across land cover types and subbasins. We found that 65% of the study area (2.5 million km2) showed significant (p < 0.05) positive correlations between monthly ET and rainfall, whereas 7% showed significant negative correlations. As expected, positive ET-rainfall correlations were observed over natural vegetation, mixed croplands/natural vegetation, and croplands, with a few subbasin-specific exceptions. In particular, irrigated croplands, wetlands and some forests exhibited negative correlations. Trend tests revealed spatial clusters of statistically significant trends in ET (6% of study area was negative; 12% positive), vegetation greenness (24% negative; 12% positive) and rainfall (11% negative; 1% positive) during 2002–2011. The Nile Delta, Ethiopian highlands and central Uganda regions showed decline in ET while central parts of Sudan, South Sudan, southwestern Ethiopia and northeastern Uganda showed increases. Except for a decline in ET in central Uganda, the detected changes in ET (both positive and negative) were not associated with corresponding changes in rainfall. Detected declines in ET in the Nile delta and Ethiopian highlands were found to be attributable to anthropogenic land degradation, while the ET decline in central Uganda is likely caused by rainfall reduction.


Alternative Methods To Predict Actual Evapotranspiration Illustrate The Importance Of Accounting For Phenology: The Event Driven Phenology Model Part Ii, V. Kovalskyy, G. M. Henebry 2016 South Dakota State University

Alternative Methods To Predict Actual Evapotranspiration Illustrate The Importance Of Accounting For Phenology: The Event Driven Phenology Model Part Ii, V. Kovalskyy, G. M. Henebry

Geoffrey Henebry

Evapotranspiration (ET) flux constitutes a major component of both the water and energy balances at the land surface. Among the many factors that control evapotranspiration, phenology poses a major source of uncertainty in attempts to predict ET. Contemporary approaches to ET modeling and monitoring frequently summarize the complexity of the seasonal development of vegetation cover into static phenological trajectories (or climatologies) that lack sensitivity to changing environmental conditions. The Event Driven Phenology Model (EDPM) offers an alternative, interactive approach to representing phenology. This study presents the results of an experiment designed to illustrate the differences in ET arising from various ...


An Automated Framework To Identify Lost And Restorable Wetlands In The Prairie Pothole Region, Ann Waz 2016 The University of Western Ontario

An Automated Framework To Identify Lost And Restorable Wetlands In The Prairie Pothole Region, Ann Waz

Electronic Thesis and Dissertation Repository

Abstract

While progress has been made in automating wetland identification, identifying lost and restorable wetlands remains a challenge. A suite of automated methods was developed and applied to the Nose Creek watershed near Calgary, Alberta to establish a historical wetland inventory and the proportion of permanently versus temporarily lost wetlands. A power-law function of wetland area vs. wetland frequency using wetlands derived from the fusion of a high resolution digital elevation model and near-infrared data identified permanent loss of 11.0% by number and 0.6% by area. The difference between historical and existing wetlands was used to estimate a ...


Estimation Of Crop Gross Primary Production (Gpp): Ii. Do Scaled Modis Vegetation Indices Improve Performance?, Qingyuan Zhang, Yen-Ben Cheng, Alexei I. Lyapustin, Yujie Wang, Xiaoyang Zhang, Andrew Suyker, Shashi Verma, Yanmin Shuai, Elizabeth M. Middleton 2016 Universities Space Research Association

Estimation Of Crop Gross Primary Production (Gpp): Ii. Do Scaled Modis Vegetation Indices Improve Performance?, Qingyuan Zhang, Yen-Ben Cheng, Alexei I. Lyapustin, Yujie Wang, Xiaoyang Zhang, Andrew Suyker, Shashi Verma, Yanmin Shuai, Elizabeth M. Middleton

Xiaoyang Zhang

Satellite remote sensing estimates of gross primary production (GPP) have routinely been made using spectral vegetation indices (VIs) over the past two decades. The Normalized Difference Vegetation Index (NDVI), the Enhanced Vegetation Index (EVI), the green band Wide Dynamic Range Vegetation Index (WDRVIgreen), and the green band Chlorophyll Index (CIgreen) have been employed to estimate GPP under the assumption that GPP is proportional to the product of VI and photosynthetically active radiation (PAR) (where VI is one of four VIs: NDVI, EVI, WDRVIgreen, or CIgreen). However, the empirical regressions between VI*PAR and GPP measured locally ...


A Comparison Of Tropical Rainforest Phenology Retrieved From Geostationary (Seviri) And Polar-Orbiting (Modis) Sensors Across The Congo Basin, Dong Yan, Xiaoyang Zhang, Yunyue Yu, Wei Guo 2016 South Dakota State University

A Comparison Of Tropical Rainforest Phenology Retrieved From Geostationary (Seviri) And Polar-Orbiting (Modis) Sensors Across The Congo Basin, Dong Yan, Xiaoyang Zhang, Yunyue Yu, Wei Guo

Xiaoyang Zhang

The seasonal and interannual dynamics of tropical rainforests play a critical role in the global carbon cycle and climate change. This paper retrieved and compared land surface phenology from observations acquired by the Spinning Enhanced Visible and Infrared Imager (SEVIRI) onboard geostationary satellites and the Moderate Resolution Imaging Spectroradiometer (MODIS) on polar-orbiting satellites over the Congo Basin. To achieve this,we first retrieved canopy greenness cycles (CGCs) and their transition timing from two-band enhanced vegetation index (EVI2) derived from SEVIRI and MODIS data between 2006 and 2013.We then assessed the influences of SEVIRI and MODIS data quality on the ...


Urban Walkability Measures: Data Quality, Cautions, And Associations With Active And Public Transportation Across Canada, Thomas C. Thayer 2016 The University of Western Ontario

Urban Walkability Measures: Data Quality, Cautions, And Associations With Active And Public Transportation Across Canada, Thomas C. Thayer

Electronic Thesis and Dissertation Repository

Geographical Information Systems (GIS) has emerged as a primary tool to study the built environment (BE) and its correlates. Accurate results employing GIS-based methods, however, depend on high-quality data sets and agreement on the appropriate nature and scale of areal units. Exploratory groundtruthing exercises illuminated possible issues of data accuracy. GIS-derived walkability measures for intersection density and land use mix were calculated for 2011 using Census of Canada data to determine whether commercially- or municipally-sourced urban data sets were better suited for BE studies. Road network data were ‘cleaned’ to remove unwalkable sections of road and to repair instances of ...


Sensitivity Of Mesoscale Modeling Of Smoke Direct Radiative Effect To The Emission Inventory: A Case Study In Northern Sub-Saharan African Region, Feng Zhang, Jun Wang, Charles Ichoku, Edward J. Hyer, Zhifeng Yang, Cui Ge, Shenjian Su, Xiaoyang Zhang, Shobha Kondragunta, Christine Wiedinmyer, Johannes W. Kaiser, Arlindo da Silva 2016 University of Nebraska - Lincoln

Sensitivity Of Mesoscale Modeling Of Smoke Direct Radiative Effect To The Emission Inventory: A Case Study In Northern Sub-Saharan African Region, Feng Zhang, Jun Wang, Charles Ichoku, Edward J. Hyer, Zhifeng Yang, Cui Ge, Shenjian Su, Xiaoyang Zhang, Shobha Kondragunta, Christine Wiedinmyer, Johannes W. Kaiser, Arlindo Da Silva

Xiaoyang Zhang

An ensemble approach is used to examine the sensitivity of smoke loading and smoke direct radiative effect in the atmosphere to uncertainties in smoke emission estimates. Seven different fire emission inventories are applied independently to WRF-Chem model (v3.5) with the same model configuration (excluding dust and other emission sources) over the northern sub-Saharan African (NSSA) biomass-burning region. Results for November and February 2010 are analyzed, respectively representing the start and end of the biomass burning season in the study region. For February 2010, estimates of total smoke emission vary by a factor of 12, but only differences by factors ...


Interannual Variation In Biomass Burning And Fire Seasonality Derived From Geostationary Satellite Data Across The Contiguous United States From 1995 To 2011, Xiaoyang Zhang, Shobha Kondragunta, David Roy 2016 South Dakota State University

Interannual Variation In Biomass Burning And Fire Seasonality Derived From Geostationary Satellite Data Across The Contiguous United States From 1995 To 2011, Xiaoyang Zhang, Shobha Kondragunta, David Roy

Xiaoyang Zhang

Wildfires exhibit a strong seasonality that is driven by climatic factors and human activities. Although the fire seasonality is commonly determined using burned area and fire frequency, it could also be quantified using biomass consumption estimates that directly represent biomass loss (a combination of the area burned and the fuel loading). Therefore, in this study a data set of long-term biomass consumed was derived from geostationary satellite data to explore the interannual variation in the fire seasonality and the possible impacts of climate change and land management practices across the Contiguous United States (CONUS). Specifically, daily biomass consumed data were ...


Improving The Performance Of Ice Sheet Modeling Through Embedded Simulation, Christopher G. Dufour 2016 University of Maine

Improving The Performance Of Ice Sheet Modeling Through Embedded Simulation, Christopher G. Dufour

Electronic Theses and Dissertations

Understanding the impact of global climate change is a critical concern for society at large. One important piece of the climate puzzle is how large-scale ice sheets, such as those covering Greenland and Antarctica, respond to a warming climate. Given such ice sheets are under constant change, developing models that can accurately capture their dynamics represents a significant challenge to researchers. The problem, however, is properly capturing the dynamics of an ice sheet model requires a high model resolution and simulating these models is intractable even for state-of-the-art supercomputers.

This thesis presents a revolutionary approach to accurately capture ice sheet ...


Habitat Suitability Modeling For The Mississippi Sandhill Crane, Grus Canadensis Pulla, Linda C. Salande 2016 University of New Orleans

Habitat Suitability Modeling For The Mississippi Sandhill Crane, Grus Canadensis Pulla, Linda C. Salande

University of New Orleans Theses and Dissertations

In this study, I modeled the suitability of habitat on the Mississippi Sandhill Crane National Wildlife Refuge for the federally endangered Mississippi Sandhill Crane (Grus Canadensis pulla). Habitat type and suitability changed over time due to seasonality of vegetation and succession in the absence of burning. Cranes used highly suitable habitat more in the non-growing than in the growing season, and may have been more constrained by resource availability during winter months. Cranes used some less-suitable areas including cypress drains, which provide roosting sites, and supplemental food plots. The mismatch between predicted quality and crane use suggests that no single ...


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