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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.
351

The roles of building designers and operators in indoor air quality management

Leung, Kwok-wah., 梁國華. January 2000 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
352

A study of indoor air quality management in Hong Kong

Hui, Sum-wong., 許森煌. January 2003 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
353

Time variable parameter estimation on the wind speed air quality modelin Hong Kong

Tsang, Ho-on, Frederick., 曾可安. January 1995 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
354

To improve air quality through land use planning: a case study in Western District : urban planning in HongKong

Tsang, Fung-yee., 曾鳳儀. January 1996 (has links)
published_or_final_version / Urban Planning / Master / Master of Science in Urban Planning
355

Controlling vehicular emissions in an era of rapid motorization: a case study of Guangzhou

Lee, Ka-yin, Anna., 李家賢. January 2009 (has links)
published_or_final_version / Geography / Master / Master of Philosophy
356

Analysis of urbanization and air quality in Hong Kong

Chiu, Man-chun, 趙文進 January 2009 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
357

Applications of satellite remote sensing data for regional air quality modeling

Feldman, Michael S., 1979- 16 September 2010 (has links)
Photochemical grid models are used to evaluate air pollution control strategies by simulating the physical and chemical processes that influence pollutant concentrations. Their accuracy depends on the accuracy of input data used for anthropogenic and biogenic emissions, land surface characteristics, initial and boundary conditions and meteorological conditions. Evaluation of model performance requires sufficient ambient data. This work develops approaches for applying satellite data to allow more frequent and timely estimates of parameters required to estimate emissions and pollutant removal processes for regional air quality modeling. Land use and land cover (LULC) data prepared from remote sensing satellite data were evaluated for use as inputs to photochemical grid models for estimating dry deposition velocities and biogenic emissions. The results indicated that satellite-based data derived from the Moderate Resolution Imaging Spectroradiometer instrument can be used to provide periodic updates to LULC information used in photochemical models. The sensitivity of predicted ozone concentrations to LULC data used for biogenic emission estimates was examined by comparing the database currently used for modeling in southeastern Texas with a new database prepared from Landsat satellite imagery and field data. The satellite data and image classification techniques provide useful tools for mapping and monitoring changes in LULC. However, field validation is necessary to link species and biomass densities to the classification system needed for accurate biogenic emissions estimates, especially in areas that have dense concentrations of species that emit high levels of biogenic hydrocarbons. The application of NO2 measurements from the Ozone Monitoring Instrument (OMI) to validation of NOx emission estimates and identification of emission sources for regional air quality modeling for Texas was examined. OMI observations can be used to identify regions with changes in emissions over time or where estimates have large uncertainties and to evaluate the effectiveness of emission reduction strategies. For example, in the Dallas-Fort Worth area, observed NO2 column densities from OMI indicate that emission controls are less effective than anticipated due to increased area source emissions. The techniques developed in this work have broad applicability in the advancement of methods for including satellite remote sensing data in regional air quality modeling. / text
358

Assessing sheep’s wool as a filtration material for the removal of formaldehyde in the indoor environment

Wang, Jennifer, active 21st century 11 September 2014 (has links)
Formaldehyde is one of the most prevalent and toxic chemicals found indoors, where we spend ~90% of our lives. Chronic exposure to formaldehyde indoors, therefore, is of particular concern, especially for sensitive populations like children and infants. Unfortunately, no effective filtration control strategy exists for its removal. While research has shown that proteins in sheep's wool bind permanently to formaldehyde, the extent of wool's formaldehyde removal efficiency and effective removal capacity when applied in active filtration settings is unknown. In this research, wool capacity experiments were designed using a plug flow reactor and air cleaner unit to explore the capacity of wool to remove formaldehyde given different active filtration designs. Using the measured wool capacity, filter life and annual costs were modeled in a typical 50 m₃ room for a variety of theoretical filter operation lengths, air exchange rates, and source concentrations. For each case, annual filtration costs were compared to the monetary benefits derived from wool resale and from the reduction in cancer rates for different population types using the DALYs human exposure metric. Wool filtration was observed to drop formaldehyde concentrations between 60-80%, although the effective wool removal capacity was highly dependent on the fluid mechanics of the filtration unit. The air cleaner setup yielded approximately six times greater capacity than the small-scale PFR designed to mimic active filtration (670 [mu]g versus 110 [mu]g HCHO removed per g of wool, respectively). The outcomes of these experiments suggest that kinematic variations resulting from different wool packing densities, air flow rates, and degree of mixing in the units influence the filtration efficiency and effective capacity of wool. The results of the cost--benefit analysis show that for the higher wool capacity conditions, cost-effectiveness is achieved by the majority of room cases when sensitive populations like children and infants are present. However, for the average population scenarios, filtration was rarely worthwhile, showing that adults benefit less from reductions in chronic formaldehyde exposure. These results suggest that implementation of active filtration would be the most beneficial and cost-effective in settings like schools, nurseries, and hospitals that have a high percentage of sensitive populations. / text
359

The perception of changes in visibility at Class I Parks and Wilderness areas

Parsons, Russ, 1957- January 1987 (has links)
The language of regulations implementing the 1977 Clean Air Act Amendments distinguishes between humanly detectable visibility impairment in Class I Parks and Wilderness areas and the extent to which such impairment adversely affects a park visitor's visual experience. Two lines of environmental perception research have arisen from this distinction, one emphasizing the detectability of visibility impairment, and the other emphasizing a park visitor's experience. This study attempts to deal with issues relevant to both lines of research. Subjects were shown color slides depicting varying levels of visibility in Class I Parks and Wilderness areas under four treatment conditions. A sensitivity gradient emerged from these conditions: Subjects who rated repeated versions of selected vistas for visual air quality were most sensitive to changes in visibility, while subjects who rated a random series of scenes for scenic beauty were least sensitive. Other variables (i.e., scattering angle, and the particular vista being viewed) also proved to have substantial influence on perceptual ratings.
360

Beaktande av hälsorisker från luftföroreningar vid lokalisering av nya bostäder i Stockholm : En fallstudie av fem projekt intill Essingeleden

Karlsson, Josefine January 2014 (has links)
Andelen människor som flyttar till städer ökar, vilket gör att det blir allt mer konkurrens om markytan. För att skapa fler bostäder tas mark i anspråk som tidigare haft andra syften eller bestått av naturliga grönytor. När växtlighet prioriteras bort minskar ekosystemtjänster som har förmåga att rena stadsluften. Denna studie baseras på Stockholm, där den regionala översiktsplaneringen åsyftar att staden ska förtätas för att skapa mer centrala bostäder. Att stadsluften är förorenad är ett generellt problem som utsätter invånare för hälsorisker.  Detta är en fallstudie som granskar hur luftföroreningar uppmärksammas när nya bostadsprojekt är planerade att etableras. Fem fall har valts ut nära en hårt trafikerad Europaväg, för att undersöka hur luftkvaliteter beaktats i planprocesserna. Dokument har granskats och berörda aktörer har intervjuats. Riskerna med luftföroreningar omnämns ytterst lite i vissa fall, medan de anses som betydande miljöpåverkan i andra. Detta har lett till att miljökonsekvensbeskrivningar (MKB) krävts vid vissa bostadsprojekt men inte i andra, trots att liknande eller högre nivåer av luftföroreningar eller fordonsmängd uppmätts eller beräknats vid projekten som uppmärksammat aspekten minst. Resultaten i fallstudien belyser den varierande förekomsten av omnämnandet om luftföroreningar och därmed risker för människors hälsa i de olika bostadsprojekten. / The numbers of people that are living in cities are expanding. That means an arising competition of the ground surface. To create enough homes areas that earlier was filled with natural green spaces are sometimes becoming mobilized. Green space’s that seems to clean the air becomes rarer. This study is based on the city of Stockholm, that is planned to expand more towards the central parts of the city. The city air is as in many other cities polluted and citizens are exposed to health risks.  This is a case study that examines how air pollution is being noticed in new residential projects. Five projects located close to a heavy traffic road have been chosen. Documents have been surveyed and relevant stakeholders have been interviewed in reason to find out how air quality is being observed. The different concerns regarding air quality has lead to decisions that environmental impact assessment (EIA) has being required in some cases, but not in others. Thus the levels of air quality or traffic density have approximately been the same or sometimes even higher in the cases that mentioned air quality least. This case study highlights the varied mention about air pollution and thereby the risks for human health in the studied projects.

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