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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.
211

Effect of high occupancy toll (HOT) lanes on mass vehicle emissions: an application to I-85 in Atlanta

Kall, David 10 July 2008 (has links)
High Occupancy Toll (HOT) lanes were recently proposed for I-85 in Atlanta as a way to relieve congestion and provide a reliable commute time for single occupant drivers that are willing to pay a toll. It is important to evaluate the air quality impacts of such a proposal to meet environmental regulations, such as the National Environmental Policy Act (NEPA) and Transportation Conformity Regulations. The goal of this study is to understand how vehicle mass emissions change as a result of implementing HOT lanes on I-85 in Atlanta . This is done by considering a number of factors affect mass vehicle emissions, such as vehicle activity, vehicle speeds, vehicle age distributions, and vehicle class distributions. These factors are incorporated into a base scenario, which models the current condition on I-85 with HOV lanes, and a future scenario, which models the implementation of HOT lanes on this corridor. The base scenario mainly uses data from a data collection effort by Georgia Tech during the summer of 2007 on the I-85 corridor, while the future scenario makes alterations to these data using information from other cities that have already implemented HOT lanes. The MOBILE-Matrix modeling tool, which was recently developed by Georgia Tech [16], was used to run the emissions analysis using the input factors from these data sources. This tool calculated mass emissions for five pollutants: HC, NOx, CO, PM2.5, and PM10. The results show very small increases in mass emissions for NOx, CO, PM2.5, and PM10, and very small decreases in mass emissions for HC. Therefore, the implementation of HOT lanes on I-85 in Atlanta is unlikely to violate the Transportation Conformity Rule. For NEPA purposes, this analysis could be used to make the case that air quality impacts are not significant, and therefore further detailed analyses are not required.
212

BMI changes, dietary intake and physical activity of immigrants in the USA : an investigation of a South African population in the greater Atlanta area

Viljoen, Ida 12 1900 (has links)
Thesis (Mnutr)--Stellenbosch Univresity, 2004. / ENGLISH ABSTRACT: INTRODUCTION: The aim of this study was to investigate post-immigration BMI changes in a South African immigrant population and how dietary intake and habitual physical activity reflect these changes. The study was designed as a cross-sectional, observational survey. Thirty-six volunteers aged 20 - 50 years were included in the sample. Volunteers were South African immigrants in the Atlanta area, USA, who have lived in the USA for more than 6 months but less than 5 years. METHOD: Subjects were required to complete four questionnaires including a selfadministered socia-demographic, physical activity and food frequency questionnaire. The weight history questionnaire containing measurements including height, weight and waist circumference was completed by the investigator. RESULTS: A significant increase in BMI was indicated for both male (p=0.036) and female (p=0.0009) subjects. The increase in BMI for two age categories, 20-29 years (p = 0.018) and 30-39 years (p = 0.006), was also significant. Forty five percent of females reported an energy intake above the Estimated Energy Requirement (EER) for active individuals. Reported saturated fatty acid intake (13% of TE) exceeded the Acceptable Macronutrient Distribution Range (AMOR). The prevalence of inadequate n-3 and n-6 PUFA as well as fibre intake was high, especially in men. Sixty four percent of the population had a 'low active' physical activity level (PAL). CONCLUSION: The observed increase in post-immigration BMI implies that the South African immigrant population, similar to other immigrant populations, has adopted to some extent, the lifestyle and dietary habits of the general US population. As a result, the South African immigrant population may also be subject to increased chronic disease risk. / AFRIKAANSE OPSOMMING: INLEIDING: Die doel van hierdie studie was om die veranderinge in liggaamsmassa index (LMI) wat met immigrasie gepaard gaan in In Suid-Afrikaanse immigrant populasie te ondersoek, asook hoe die populasie se dieet en fisieke aktiwiteit hierdie veranderinge reflekteer. Die studie was In dwarssnit, observasie opname. Die steekproef het bestaan uit 36 vrywilligers (20 - 50 jaar oud). Respondente was deel van In Suid-Afrikaanse immigrant populasie in die Atlanta area, VSA, wat vir langer as 6 maande en korter as 5 jaar in die VSA woonagtig was. METODE: Respondente is versoek om vier vraelyste te voltooi insluitende In sosiodemografiese, fisieke aktiwiteit, -en voedsel frekwensie vraelys. Antropometriese metings, insluitende massa, lengte en middelomtrek is deur die navorser op die massa geskiedenis vraelys aangeteken. RESULTATE: In Betekenisvolle toename in LMI vir beide mans (p=0.036) en vroue (p=0.0009) is gevind. Die toename in LMI vir respondente 20-29 jaar (p = 0.018) en 30- 39 jaar (p = 0.006) was ook betekenisvol. Vyf-en-veertig persent vroue se energie inname was hoër as die aanbevole daaglikse inname vir aktiewe individue. Die populasie se versadigde vetsuur inname (13% van totale energie) was hoër as die aanvaarbare makronutriënt verspreiding. Die prevalensie vir onvoldoende innname van n-3 en n-6 poli-onversadigde vetsure, asook vesel inname was hoog, veralonder mans. Vier-en-sestig persent van die populasie se fisieke aktiwiteit vlak is geklassifiseer as 'lae aktiwiteit' . GEVOLGTREKKING: Die waargenome toename in LMI impliseer dat die studie populasie, soortgelyk aan ander immigrant populasies, die lewensstyl en dieet gewoontes van die algemene Amerikaanse populasie tot In sekere mate aangeneem het en is dus ook onderhewig aan die gevolglike toename in risiko vir kroniese siekte van lewensstyl.
213

Three essays in program evaluation: the case of Atlanta inspection and maintenance program

Supnithadnaporn, Anupit 17 June 2009 (has links)
The Atlanta Inspection and Maintenance program ultimately aims to reduce on-road vehicular emission, a major source of air pollution. The program enforces eligible vehicles to be inspected and repaired, if necessary, before the annual registration renewal. However, various factors can influence the program implementation with respect to the motorists, inspectors, and testing technology. This research explores some of these factors by using empirical data from the Continuous Atlanta Fleet Evaluation project, the inspection transaction records, the Atlanta Household Travel Survey, and the U.S. Census Bureau. The study discusses policy implications of findings from the three essays and offers related recommendations. The first essay examines whether the higher income of a vehicle owner decreases the odds of the vehicle failing the first inspection. Findings show that vehicles owned by low-income households are more likely to fail the first inspection of the annual test cycle. However, after controlling for the vehicle characteristics, the odds of failing the first inspection are similar across households. This suggests that the maintenance behaviors are approximately the same for high- and low-income households. The second essay explains the motorists' decisions in selecting their inspection stations using a random utility model. The study finds that motorists are likely to choose the inspection stations that are located near their houses, charge lower fees, and can serve a large number of customers. Motorists are less likely to choose the stations with a relatively high failure ratio especially in an area of low station density. Moreover, motorists do not travel an extra mile to the stations with lower failure ratio. Understanding choices of vehicle owners can shed some light on the performance of inspection stations. The third essay investigates the validity and reliability of the on-board diagnostic generation II (OBD II) test, a new testing technology required for 1966 and newer model year vehicles. The study compares the inspection results with the observed on-road emission using the remote sensing device (RSD) of the same vehicles. This research finds that the agreement between the RSD measurement and the OBD II test is lower for the relatively older or higher use vehicle fleets
214

A profile of changes in vehicle characteristics following the I-85 HOV-to-HOT conversion

Duarte, David 15 April 2013 (has links)
A 15.5-mile portion of the I-85 high-occupancy vehicle (HOV) lane in the metropolitan area of Atlanta, GA was converted to a high-occupancy toll (HOT) lane as part of a federal demonstration project designed to provide a reliable travel option through this congested corridor. Results from the I-85 demonstration project provided insight into the results that may follow the Georgia Department of Transportation's planned implementation of a $16 billion HOT lane network along metropolitan Atlanta's other major roadways [2]. To evaluate the impacts of the conversion, it was necessary to measure changes in corridor travel speed, reliability, vehicle throughput, passenger throughput, lane weaving, and user demographics. To measure such performance, a monitoring project, led by the Georgia Institute of Technology collected various forms of data through on-site field deployments, GDOT video, and cooperation from the State Road and Toll Authority (SRTA). Changes in the HOT lane's speed, reliability or other performance measure can affect the demographic and vehicle characteristics of those who utilize the corridor. The purpose of this particular study was to analyze the changes to the vehicle characteristics by comparing vehicle occupancy, vehicle classifications, and vehicle registration data to their counterparts from before the HOV-to-HOT conversion. As part of the monitoring project, the Georgia Tech research team organized a two-year deployment effort to collect data along the corridor during morning and afternoon peak hours. One year of data collection occurred before the conversion date to establish a control and a basis from which to compare any changes. The second year of data collection occurred after the conversion to track those changes and observe the progress of the lane's performance. While on-site, researchers collected data elements including visually-observed vehicle occupancy, license plate numbers, and vehicle classification [25]. The research team obtained vehicle records by submitting the license plate tag entries to a registration database [26]. In previous work, vehicle occupancy data were collected independently of license plate records used to establish the commuter shed. For the analyses reported in this thesis, license plate data and occupancy data were collected concurrently, providing a link between occupancy records of specific vehicles and relevant demographic characteristics based upon census data. The vehicle records also provided characteristics of the users' vehicles (light-duty vehicle vs. sport utility vehicle, model year, etc.) that the researchers aggregated to identify general trends in fleet characteristics. The analysis reported in this thesis focuses on identifying changes in vehicle characteristics that resulted from the HOV-to-HOT conversion. The data collected from post-conversion are compared to pre-conversion data, revealing changes in vehicle characteristics and occupancy distributions that most likely resulted from the implementation of the HOT lane. Plausible reasons affecting the vehicle characteristics alterations will be identified and further demographic research will enhance the data currently available to better pinpoint the cause and effect relationship between implementation and the current status of the I-85 corridor. Preliminary data collection outliers were identified by using vehicle occupancy data. However, future analysis will reveal the degree of their impact on the project as a whole. Matched occupancy and license plate data revealed vehicle characteristics for HOT lane users as well as indications that the tested data collectors are predominantly synchronized when concurrently collecting data, resulting in an argument to uphold the validity of the data collection methods. Chapter two provides reasons for why HOT lanes were sought out to replace I-85's HOV lanes. Chapter two will also provide many details regarding how the HOT lanes function and it will describe the role the Georgia Institute of Technology played in the assessment the HOV-to-HOT conversion. Chapter three includes the methodologies used to complete this document while chapter four provides results and analysis for the one year period before the conversion and the one year period after the conversion.
215

Living outside the box: sustaining the lifelong community through universal design

Ricks, Joi Elizabeth 08 July 2010 (has links)
We all want to live in a healthy community. Each of us has his or her own image of what such a community should look like. That image is shaped, in part, by our reaction to the communities in which we now live or used to live. However we often take for granted the elements of communities that enable and sometimes disable many of us to remain active in a community for a lifetime. For older residents, a lifelong community would include elements that help them to maintain independence and quality of life. The physical characteristics of a community often play a major role in facilitating our personal independence. In order to combat the growing challenges and health concerns facing the American lifestyle this research proposes a set of design guidelines that promote sustainable lifelong communities that are universally designed for people of all ages and levels of physical ability. The purpose of developing a set of universal design guidelines for lifelong communities is to alleviate many of the physical barriers and challenges that prevent some Americans from active involvement in the community. The methods employed to develop these guidelines were based on literature review and analysis. This research was incorporated into a new body of practical standards that was tested against a real life community in Decatur, Georgia. These standards were edited and revised to appropriately accommodate the necessary adaptations that were discovered during the evaluation phase. The resultant guidelines are presented with the intention of becoming a usable guide for planning agencies such as the Atlanta Regional Commission and other local and national community design facilitators.
216

Assessing the marginal cost of freeway congestion for vehicle fleets using passive GPS speed data

Wood, Nicholas Stephen 08 July 2010 (has links)
This thesis examines the marginal cost of congested travel to a variety of businesses by observing time spent in congestion and estimating excess labor costs based upon the relevant value of time. The fleets in the scoping study represented commercial deliveries of goods and services, government agencies, and transit systems. Observations on limited-access expressways within the 13-county Atlanta metropolitan region were used in the analysis. Vehicles were monitored by using a passive GPS assembly that transmitted speed and location data in real-time to an off-site location. Installation and operation during the observation period required no interaction from the driver. Over 217 hours of good freeway movement during 354 vehicle-days was recorded. Rates of delay, expressed as a unit of lost minutes per mile traveled, were calculated by taking the difference in speeds observed during congestion from an optimal free-flow speed of 45 mph and dividing that by the distance traveled per segment. The difference between the 50th and 95th percentile delay rates was used as the measure for travel unreliability. Daily average values of extra time needed per fleet vehicle to ensure on-time arrivals were derived, and the median buffer across all fleets was 1.65 hours of added time per vehicle. Weekly marginal costs per fleet vehicle were estimated by factoring in the corresponding driver wages or hourly operation costs (for transit fleets). Equivalent toll rates were calculated by multiplying the 95th percentile delay rate by the hourly costs. The equivalent toll per mile traveled was representative of an equal relationship between the marginal costs of congestion experienced and a hypothetical state of free-flow travel (under first-best rules of marginal cost pricing). The median equivalent toll rates across all fleets was $0.43 per mile for weekday mornings, $0.13 per mile for midday weekdays, $0.53 per mile for afternoon weekdays and $0.01 per mile for weekday nights and weekends.
217

Rethinking downtown highways

LaRoche, Lealan Dorothy Marie 21 December 2010 (has links)
Freeways have had a strong influence not only on the urban transportation but also on downtown areas both physically and socially. Certainly, they have extended the commuting limits of the city and made lower land costs more accessible. However, many of the mid-century freeways, once championed by planners as tools for urban renewal, have created swaths of blight through city neighborhoods. Their negative impacts on the larger urban framework requires new ideas for healthier alternatives to aid in preserving and building sustainable cities. Removal of any downtown highway requires careful thought— even more consideration than when it was built. Quick solutions are what resulted in the problems that downtown highways of the Interstate-Era have today. If it is the simple interactions between people and place are that make up the positive aspects an urban environment, then what are the possibilities and strategies for removing urban highway, which are one of the primary impediments separating people in place in contemporary cities? This question is the focus of this thesis. At its core, the removal of freeways represents a trade-off between mobility objectives and economic development objectives. Evidence from other cities’ decisions to redesign or remove their downtown highways suggests multiple benefits. Making design changes, such as to replace a downtown highway with a well-designed surface boulevard, can stimulate economic activities without necessarily causing traffic chaos. Solutions come in different shapes and sizes. The selected case studies in this thesis reflect a diversity of approaches – suggesting no single strategy exists for addressing downtown highway issues. This reflects the fact that multiple alternatives must be considered in every situation because each approach varies in costs and opportunities. A typology of highway alternations derived from the case studies includes seven different techniques: burying, demolishing, taming, capping or bridging, elevating, retaining, and relocating. The final chapter applies the conclusions from the case studies to the Downtown Connector– Interstate 75/85– in Downtown Atlanta, Georgia. Urban design and transportation planning has an emerging new set of values. Transportation planning is seeking to promote alternate modes of transportation to the private vehicle, like transit, by foot, or by bicycle. We now understand that connectivity is not served only by highways but also by urban street networks that invite modes other than just automobiles. An important role for urban design will be to shape the way these interactions are made to benefit the citizens, its urban spaces, and the economy.
218

Reconfiguring Memories of Honor: William Raoul's Manipulation of Masculinities in the New South, 1872-1918

Blankenship, Steve Ray 24 April 2007 (has links)
This dissertation examines how honor was fashioned in the New South by examining the masculine roles performed by William Greene Raoul, Jr. Raoul wrote his autobiography in the mid-1930s and in it he reflected on his life on the New South's frontier at the turn of the century as change came to the region in all aspects of life: politically, economically, socially, sexually, and racially. Raoul was an elite son of the New South whose memoirs, "The Proletarian Aristocrat," reveals a man of multiple masculinities, each with particular ways of retrieving his past(s). The paradox of his title suggests the parallel organization of Raoul's recollections. The "aristocrat" framed the events of a lifetime through a lens of honor, sustained by southern gentlemen who restrained masculine impulses on the one hand and avoided dependency on the other. Raoul the "proletarian" cast honor through an ideological retrospective whereby traumatic memories of disappointment and failure were re-fashioned through a distinctly politicized view constructed rather than recalled. Raoul's business failures led him to re-conceptualize masculine honor as a quality possessed more by the emerging working class than the rising commercial class. Memory operates in this project as more than mere methodology as assumptions about access to the past through memory are subordinated to an examination of the meaning of the memories rehearsed by Raoul. Raoul wrote his autobiography at a bittersweet moment in his life. While his personal fortune had been nearly wiped out by the stock market crash of October 1929, he clearly looked back on his career in the New South as a committed radical with delight as the Great Depression called into question the legitimacy of the capitalist system that he had long held responsible for his own professional failures in a variety of endeavors, from the cotton-mill industry to box-car building and from saw manufacturing to a practicing accountant. Raoul converted to Socialism in part to join what he regarded as society's most progressive and virile force. It is these two voices, the proletarian and the aristocrat, that are under examination here.
219

Strike Fever: Labor Unrest, Civil Rights and the Left in Atlanta, 1972

Waugh-Benton, Monica 03 August 2006 (has links)
This thesis aims to provide a history of African American working class and Leftist activism in Atlanta, Georgia during the early 1970s. It places a series of wildcat strikes within the context of political and social transition, and charges unequal economic conditions and a racially charged discriminatory environment as primary causes. The legacies of both the Civil Rights Movement and the New Left are identified as key contributing factors to this wave of labor unrest. One path taken by former Civil Right activists was to focus on poor peoples’ movements, and one course taken by the 1960s-era New Left activists was to join forces with the working class in an attempt to build a New Communist movement. In Atlanta, these two forces converged and generated a notable force against some of city’s most prominent employers.
220

Real-time measurement of on-road fine particulate matter in Atlanta

Papier, Mark Elliot 01 April 2008 (has links)
Particulate matter is increasingly linked to health effects not only for what was previously thought to be just a respiratory problem, but also for the cardiovascular system. Literature not only supports that high particulate matter over long periods of time is correlated to morbidity and mortality due to both cardiovascular and respiratory means, but that high levels of particulate matter, even in short bursts of high concentrations, may be the triggering mechanism for the onset of such problems. Due to automobiles being a prime source of particulate matter, roadway concentrations are often higher than those measured at off-road measurement sites run by various parts of the United States Government. Furthermore, the government run sites are averaged over timescales at a minimum of an hour and at a maximum of a running three-day twenty-four hour length. These are both so long that mesoscale information about the particulate matter, such as short duration high intensity bursts, would be completely removed from the dataset. This study utilizes a real-time portable instrumentation package, which can effectively measure particulate matter concentrations on the roadways of metro Atlanta. Measurements are taken both inside the cabin of a vehicle, which does have an in-cabin filtration system, and on a bicycle ridden along the streets without any form of filtration. These instruments, specifically calibrated handheld particle counters, did indeed find some spikes of particulates above the government s one-hour averages inside the cabin of a vehicle. Arguably more importantly, while riding a bicycle these handheld particle counters also found spikes of particulates approaching six times the amount monitored by the government sites, and several roadway averages that were higher than the off-road averages for the same time.

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