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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.
181

Application of the adaptive Kalman filter to estimation of ambient air quality as an enforcement tool for the federal nondegradation air quality standards.

Crawford, Melba M. January 1981 (has links)
No description available.
182

Impact of Road Proximity and other Determinants of Air Quality along Multi-Use Trails in the National Capital Region

Tushar, Md Shazalal 04 June 2024 (has links)
Active travel can provide short-term and long-term health benefits and has the ability to reduce the negative externalities of vehicular traffic, for example, congestion, land consumption, and air pollution. However, exposure to air pollution is higher for pedestrians and cyclists than other road users when considering inhalation rate and travel distance. Route choice for active travel is a potential strategy to reduce the adverse impact of exposure to air pollution. Multi-use trails could be an effective way to reduce health impacts as the pollutant concentration is typically lower on trails, however, proximity to nearby roadways can deteriorate the air quality in multi-use trails. The goal of this study is to investigate the air pollutant concentrations on multi-use trails adjacent to different roadway classification and identify the factors that influence air quality in multi-use trails. I collected pollutant concentrations of PM2.5, particle number, and black carbon using mobile monitoring on an e-bike. I identified five trail routes that run parallel to an interstate highway, principal arterial, and local roads for this study and collected pollutant concentrations during morning, afternoon, and weekend afternoon peak hours. The average concentration of PM2.5, particle number, and black carbon was 15.62 µg/m3, 9,857 pt/cc, and 595.36 ng/m3 respectively among all the trail routes used for this study. I observed higher pollutant concentrations during morning peak hours than afternoon peak hours. Also, concentrations were lower on weekends than weekdays. The pollutant concentrations were different among multi-use trails based on their proximity and characteristics of nearby roadways. The pollutant concentrations significantly declined when the trail segment was 50-100 meters away as compared to segments within 50 meters of nearby interstates, freeways, or collectors. Concentrations increased significantly for trail segments having a nearby road Annual Average Daily Travel (AADT) of more than 32,000. The regression models explain 65%, 59%, and 52% of variability in the PM2.5, particle number, and black carbon concentrations respectively. Nearby road AADT and road density were found to be significant for PM2.5, particle number, and black carbon concentrations. Cooking place (rest areas with barbeque grills) and construction sites were significant and positively associated with PM2.5 concentrations. Airport and construction sites near trails showed a positive relation to the particle number concentration. Parking spaces near trails increase the concentration of black carbon along trails. This study shows the impact of roadway proximity on the air quality of trails which should be considered by municipalities while planning for multi-use trail network to mitigate health risks of pedestrians and bicyclists on trails. / Master of Urban and Regional Planning / Traffic related pollutants such as PM2.5, particle number, and black carbon can cause short and long terms health impacts. Exposure to these pollutants varies by travel mode, duration, route selection, etc. People who bike or walk have higher exposure than other users when taking the inhalation rate and travel duration into account. Hence, route choice is important in active travel. Multi-use trails could be effective to reduce exposure as the pollutant concentrations are typically lower on multi-use trails. However, multi-use trails are often in close proximity to pollution sources (i.e. roadways). This study focuses on identifying the impacts of road proximity and other determinants of air quality along multi-use trails. I selected five multi-use trails based on the classification of adjacent roadway and collected air quality data. I found that air quality differs along trails based on the proximity of nearby roadway and the trail route along interstate highway had the highest concentration of pollutants. The concentrations of pollutants were higher during morning than afternoon and also, it was higher during the weekdays than weekends. Trail segments within 0-50m distance of a nearby interstate or freeway had the highest concentration which decreased as the distance from the interstate or freeway increased. Construction site, airport, and BBQ place along trails also worsened air quality on multi-use trails. This study demonstrates the importance of selecting trail locations when planning for the trail network to improve the air quality on multi-use trails that will further improve the benefits of active travel.
183

Monitoring urban air quality in Hong Kong: implications of an investigation of street-level concentrations ofrespirable suspended particulates (RSP) using a light scatteringmeasurement device

Ng, Chi-yun, Jeanne., 吳芷茵. January 2000 (has links)
published_or_final_version / Urban Planning and Environmental Management / Doctoral / Doctor of Philosophy
184

Breathe the air in Hong Kong air quality sustainability

鄧慶輝, Tang, Hing-fai. January 2002 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
185

Regional and urban evaluation of an air quality modelling system in the European and Spanish domains

Pay Pérez, Maria Teresa 22 November 2011 (has links)
El impacto de la contaminación del aire es un tema crítico para el medioambiente y el clima. Una mala calidad del aire es un tema de importancia para la salud pública, especialmente en ambientes urbanos. El material particulado (PM), el ozono (O3) y el dióxido de nitrógeno (NO2) son los contaminantes más problemáticos en Europa y España. La Comisión Europea ha mostrado una gran preocupación por desarrollar técnicas que permitan incrementar el conocimiento sobre la dinámica de los contaminantes atmosféricos para asegurar el cumplimiento de la legislación y para informar a la población acerca de sus niveles. Además, la directiva europea 2008/50/CE establece la posibilidad de usar técnicas de modelización para informar sobre calidad del aire. Esta tesis doctoral está desarrollada en el marco de dos proyectos: El proyecto CALIOPE y el proyecto CICYT CGL2006-08903, ambos basados en la necesidad de desarrollar un sistema de calidad del aire que permita informar y entender los niveles de contaminación en Europa y España, con el objetivo de obtener un preciso pronóstico de la calidad del aire. Con ese propósito, el sistema de modelización CALIOPE se ha desarrollado con alta resolución espacial y temporal sobre Europa (12 km x 12 km y 15 capas, 1 hora), dominio madre, y España (4 km x 4 km y 15 capas, 1 hora), dominio anidado. CALIOPE consiste en un conjunto de modelos que tienen en cuenta la contaminación tanto antropogénica como natural. La disponibilidad del supercomputador MareNostrum, alojado en el Barcelona Supercomputer Center- Centro Nacional de Supercomputación, ha permitido trabajar a tan alta resolución. El objetivo principal de esta tesis es aumentar la confianza científica en el sistema CALIOPE, identificando sus puntos fuertes y débiles con un nivel de detalle que contribuya a establecer necesidades de mejora en el proceso de modelización. Por tanto, el presente trabajo ha evaluado espacial y temporalmente las simulaciones de calidad del aire sobre Europa y España en términos de O3, NO2, SO2, PM2.5 y PM10 en superficie sobre el año completo 2004. Para identificar el origen de las incertidumbres en la modelización del PM, su composición química ha sido también evaluada en ambos dominios. Las evaluaciones han sido realizadas sobre más de 150 estaciones de calidad del aire (más de 2 millones de datos experimentales). Además, esta tesis ha usado el sistema CALIOPE para analizar los patrones de calidad del aire sobre 2004, identificando claramente las áreas de contaminación. Las ideas más importantes que se desprenden de esta tesis son tres. Primero, las condiciones de contorno químicas basadas en un modelo global, como el LMDz-INCA2, son esenciales para modelizar el O3 troposférico sobre los dominios de estudio. Segundo, para simular la concentración de PM en el sur de Europa, tanto a escala rural como urbana, la contribución de polvo procedente del desierto del Sahara deber ser considerada debido a la proximidad al continente africano. La contribución del polvo del desierto a través del modelo BSC-DREAM8b ayuda satisfactoriamente a modelizar los picos de PM10 observados. Tercero, para ser capaz de modelizar la calidad del aire a escala urbana sobre España es esencial (1) una alta resolución espacial y temporal que permita describir fenómenos mesoescalares en áreas de topografía compleja , (2) un modelo de emisiones altamente desagregado como HERMES; (3) unos modelos que representen el estado actual del conocimiento en meteorología y química atmosférica / The impact of air pollution is a critical topic in environment and climate. Poor air quality is an important public health issue, especially in urban environments. Particulate matter (PM), tropospheric ozone (O3) and nitrogen dioxide (NO2) are the main problematic pollutants in Europe and Spain. The European Commission has shown a great concern for developing actions that allow increasing the knowledge on dynamics of atmospheric pollutants to assure the accomplishment of legislation and to inform the population about their levels. The European directive 2008/50/EC establishes the possibility of using modelling techniques to assess air quality. This Ph.D. thesis is developed in the framework of two projects: the CALIOPE project and the CGL2006-08903 CICYT project, both based on the necessity to develop an air quality modelling system that allows assessing and understanding the air pollution levels in Europe and Spain, with the aim of obtaining a precise air quality forecast. For that purpose, the CALIOPE air quality modelling system has been developed with high spatial and temporal resolution over Europe (12 km x 12 km, 1 h), as a mother domain; and Spain (4 km x 4 km, 1 h), as the nested domain. The CALIOPE system consists in a set of models that take into account both anthropogenic and natural pollution. The availability of the MareNostrum supercomputer, held in Barcelona Supercomputing Center- Centro Nacional de Supercomputación, has allowed such configuration of the CALIOPE system. The main objective of the present Ph.D. thesis is to increase the scientific confidence on the CALIOPE system, identifying skills and weakness with a degree of detail that contributes to establish necessities of improvements in the modelling process. Therefore, the present work has spatially and temporally evaluated CALIOPE air quality simulations over Europe and Spain in terms of O3, NO2, SO2, PM2.5, PM10 concentrations over the full year 2004. In order to identify the origin of uncertainties in PM modelling, PM chemical composition has been also evaluated in both target domains. Evaluations have been performed across more than 150 air quality-monitoring stations and over more than 2 million of experimental data. Furthermore, this Ph.D. thesis has used the CALIOPE system to assess air quality pattern over the year 2004, identifying clearly the areas of air pollution. There are three major thrusts of the present Ph.D. thesis. First, chemical boundary condition based on a global model, such as LMDz-INCA2, becomes essential to model O3 background concentrations in the target domains. Second, to simulate PM concentration in southern Europe, both regional and urban scales, the contribution of dust from the Saharan desert should be taken into account, since that region is frequently affected by dust outbreaks due to its proximity to the African continent. The contribution of desert dust through the BSC-DREAM8b helps to satisfactory model the observed episodic PM10 concentration peaks. Even more, the contribution of sea-salt aerosol is especially important over coastal areas. Third, to be able to model the air quality in urban scale over Spain it is essential (1) a high spatial (4 km x 4 km and 15 layers) and temporal (1h) resolution that allows describing mesoscale phenomena in very complex terrains; (2) a high disaggregated emission model to describe the sources, such as HERMES; and (3) an state-of-the-science meteorological and chemical models. This Ph.D. thesis has demonstrated that CALIOPE system applied over Europe and Spain is a useful tool which may contribute to (1) forecast air pollution in urban/suburban areas with a pervasive influence of anthropogenic emissions on a local scale and over very complex terrains and meteorology patterns; (2) assess about air pollution, discriminating between anthropogenic and natural episodes; and (3) manage air pollution, by means of modification of urban strategies or requirements of the legislation.
186

Use of inverse modeling in air quality management

Akhtar, Farhan Hussain 21 August 2009 (has links)
Inverse modeling has been used in the past to constrain atmospheric model parameters, particularly emission estimates, based upon ambient measurements. Here, inverse modeling is applied to air quality planning by calculating how emissions should change to achieve desired reduction in air pollutants. Specifically, emissions of nitrogen oxides (NOx = NO + NO2) are adjusted to achieve reductions in tropospheric ozone, a respiratory irritant, during an historic episode of elevated concentrations in urban Atlanta, GA. Understanding how emissions should change in aggregate without specifying discrete abatement options is particularly applicable to long-term and regional air pollution management. Using a cost/benefit approach, desired reductions in ozone concentrations are found for a future population in Atlanta, GA. The inverse method is applied to find NOx emission adjustments to reach this desired reduction in air pollution. An example of how emissions adjustments may aid the planning process in two neighborhoods is demonstrated using urban form indicators from a land use and transportation database. Implications of this method on establishing regional and market-based air quality management systems in light of recent legal decisions are also discussed. Both ozone and secondary particulate matter with diameters of less than 2.5μm (PM2.5) are formed in the atmosphere from common precursor species. Recent assessments of air quality management policies have stressed the need for pollutant abatement strategies addressing these mutual sources. The relative contribution of several important precursor species (NOx, sulfur dioxide, ammonia, and anthropogenic volatile organic compounds) to the formation of ozone and secondary PM2.5 in Atlanta during May 2007 - April 2008 is simulated using CMAQ/DDM-3D. This sensitivity analysis is then used to find adjustments in emissions of precursor species to achieve goal reductions for both ozone and secondary PM2.5 during a summertime episode of elevated concentrations. A discussion of the implications of these controls on air pollutant concentrations during the remaining year follows.
187

Air pollution control and economic activities : the case of Hong Kong /

Tse, Chin-wan. January 1986 (has links)
Thesis (M. Soc. Sc.)--University of Hong Kong, 1987.
188

Air quality in the Houston Ship Channel region : an environmental and land use analysis

Nasser, Omar Maher 04 December 2013 (has links)
Despite federal, state, and local efforts to combat environmental injustices resulting from heavy industrial activity and high air pollution levels, there is a widespread tendency for hazardous industrial activities to locate near low-income, underrepresented ethnic populations in the United States. The Houston Ship Channel, a port containing the largest concentration of Petrochemical Facilities in the United States, evidences this tendency and provides a stellar example of the nexus between poverty, race, industrial location, and air pollution levels. As a result of the heavy industrial activities in the East Houston area adjacent to the Houston Ship Channel, the surrounding residential area’s air quality levels are significantly poor in relation to federal, state, and local standards. Not coincidentally, these neighborhoods are predominantly low-income and Hispanic in makeup. Unfortunately, there exist few or no federal or state accountability and enforcement mechanisms to resolve this serious problem. In addition, Houston’s lack of zoning and weak land use regulations provides little opportunity for the situation to improve. Although community organization efforts have succeeded in terms of mobilization, education, and consensus building, more effective local planning tools, supported by federal regulations and applied research, would serve to remove the roadblocks that have hindered the advancement of policies promoting enhanced air quality controls, and thus improve the quality of life of the residents of East Houston. / text
189

An assessment of local government capacity in KwaZulu-Natal to implement the National Environmental Management : Air Quality Act.

Naiker, Yegeshni. January 2007 (has links)
The radical shift in approach to the Air Quality Management (AQM) strategy that has been introduced recently, through the promulgation of the National Environmental Management: Air Quality Act (AQA), makes provision for a number of innovative measures in the control of air pollution in South Africa. These include the appointment of Air Quality Officers, the development of Air Quality Management Plans, the designation of priority areas, the provision for stricter enforcement conditions, and the broad implementation of monitoring. A significant change is in the form of delegating the greatest responsibility for implementation of measures to the local government tier, comprised of metropolitan areas, district and local municipalities. Local authorities are recognised as a sphere of government, however, they are impeded, inter alia, by matters of limited financial resources, lack of skills capacity, and the slow transformation of organisational culture and structure (Cloete, 2002). The implementation ofthe AQA by local government is framed by an understanding ofthe responsibilities of local government, as well as the principal components of AQM and their implementation. The selected areas for study are Uthungulu, Uthukela, and Ugu district municipalities in KwaZulu-Natal, representing administrative and geographical variation. Existing and potential air quality issues, and their plans to address these issues, were identified and assessed in the municipalities using the Integrated Development Plans. The capacity of municipalities to implement the AQA was assessed using interviews, focusing on the interpretation of the AQA, technical capabilities, and implementation of AQM. Awareness of municipal responsibilities under the AQA was limited, although advances in AQM implementation had been made by municipalities. Responsibilities reflecting technical measures or activities that were currently undertaken by the municipality, such as monitoring and enforcement, were well recognised. However, the related policy and management tools, of Air Quality Officer (AQO) appointment and Air Quality Management Plan (AQMP) development, were less emphasised by municipal respondents. Limited progress in implementation of the AQA was observed, with only AQO appointment and ambient monitoring being significantly applied. The greatest challenge facing municipalities is the securing of financial resources for personnel and equipment. Progress in technical fundamentals is noted, most notably in emission inventories and monitoring capabilities, although communication on air quality issues remains poor, with limited mechanisms in place for inter-governmental or public communication. There is a prevalence of the use of AQMPs as planning tools, as well as general concepts of town planning and zoning. However, in general, planning departments are not involved. A significant proportion of municipalities have a means of assessing progress, whether explicitly or not. A framework for implementing the AQA is produced to guide local government efforts, and provides a summation of the outcomes of the research. / Thesis (M.Sc.)-University of KwaZulu-Natal, 2007.
190

Oro kokybės valdymas Šiaulių aerobiologinės situacijos pavyzdžiu / Air quality management after example of aerobiological situation in Šiauliai

Kazlauskienė, Viktorija 16 August 2007 (has links)
Viktorija Kazlauskienė Oro kokybės valdymas Šiaulių aerobiologinės situacijos pavyzdžiu. Magistro darbas. Šiaulių miesto aerobiologinės situacijos įvertinimas atskleidė, kad beržo, žolių ir piktžolių žiedadulkių ribinės užterštumo vertės dažnai viršijamos dėl per didelio, nenatūralaus šių augalų paplitimo. Dabartiniai teisės aktai nereglamentuoja oro kokybės, apspręstos žiedadulkių, valdymo; visuomenei nėra žinoma nei kokia aerobiologinė situacija yra, nei kaip ji turėtų būti gerinama. Todėl magistro darbe susisteminti ir išanalizuoti bendrieji oro kokybės valdymą reglamentuojantys teisės aktai. Siekiant bent iš dalies užpildyti reglamentuose rastus trūkumus, pasiūlyti nepageidautinos situacijos gerinimo techniniai ir organizaciniai sprendimo būdai. Greta to, atlikta žmonių, sergančių polinozėmis nuomonės analizė. Šių duomenų pagrindu bei remiantis užsienio šalių patirtimi, pasiūlytas patogiausias visuomenės informavimo būdas. / Viktorija Kazlauskienė Air quality management after example of aerobiological situation in Šiauliai. Master‘s work. Estimation of aerobiological situation in Šiauliai revealed that marginal pollution values of birch, grasses and weeds pollen are often overstepped because of their wide, non-natural distribution. Contemporary law deeds doesn‘t regulates management of pollen-induced air quality hence public is not aware about aerobiological situation nor the ways of it‘s improvement. Therefore common law deeds were analyzed and systematized in this work. In order to fill although at least gaps found in these, technical and organizational means of improvement of this unpleasant situation were proposed. Jointly, the analysis of public opinion among allergic people was implemented. Based on this and according to foreign countries experience, the most convenient manner of information spread was proposed.

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