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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.
1

Modeling the Effects of Local Air Pollution Control Measures on Air Quality in the Shenandoah Valley

Bansal, Gaurav 28 August 2008 (has links)
Air quality in the Shenandoah Valley has deteriorated in recent years. The valley exceeds the National Ambient Air Quality Standards for ozone (O3) a few days each year, and with stricter fine particulate matter (PM2.5) standards coming into effect, the valley risks exceeding those as well. Visibility is poor in the valley region, and the haze obscures the spectacular vistas from the Shenandoah National Park. To solve the growing problem local governments in the valley joined forces to find economically and politically feasible ways to reduce air pollution. In this study we aim to provide the scientific basis for air quality management strategies through modeling the sensitivity of various pollutants to changes in emissions. We distinguish between locally generated versus regionally transported air pollution as well as assess the impacts of proposed local air pollution control measures on ambient air quality in the valley. The first part of this thesis assesses air pollutant emissions in the Shenandoah Valley. Emissions were assigned to one of 14 source categories and allocated by county or city. Biogenic sources were responsible for 56% of the volatile organic compounds (VOCs) emitted in the valley. VOCs are important because they, together with nitrogen oxides (NOx) react to form O3 in the presence of sunlight. On-road and off-road mobile sources were the largest anthropogenic sources of VOCs as well as 63% of the NOx. PM2.5 emissions were not dominated by any single source, but fuel combustion, dust, and agriculture were important contributors. The second part of this thesis focuses on modeling ambient air pollution concentrations in the Shenandoah Valley based on the emissions generated in the first portion. We developed a set of three alternative emissions scenarios for comparison to the base case. We first zeroed anthropogenic emissions in the valley, allowing us to determine how much pollution was produced by local sources versus transported into the valley from upwind areas. We then developed a scenario that contained nine different pollution reduction strategies being considered by local governments. Finally we modeled a similar scenario in which we predicted the impact of ten proposed greenhouse gas reduction strategies on concentrations of O3 and PM2.5. We found that PM2.5 concentrations fell when emissions in the valley were reduced, but O3 did not. PM2.5 concentrations fell by 26-57% for the Zero Case and by 10-27% for the other two cases, depending on the time of year and location. Conversely for O3 there was either no change in most seasons or a small increase in concentrations in the fall. These results suggest that PM2.5 in the valley can be controlled with local measures but O3 is a more geographically wide problem. / Master of Science
2

Kartläggning & optimering av externa flöden ur ett hållbarhetsperspektiv : En fallstudie på Gestamp HardTech

Norgren, Malin, Lindberg, Elin January 2023 (has links)
In the pursuit of sustainable development, the transportation sector plays a crucial role by significantly contributing to greenhouse gas emissions. The purpose of this study is to examine how companies utilizing third-party logistics can compile and reduce transport-related emissions, more specifically investigating short- and long-term opportunities for the external flow of Gestamp HardTech in Luleå. Through a comprehensive analysis of available data, utilization of calculation models, and examination of short- and long-term opportunities, this research provides valuable insights and recommendations for companies seeking to promote sustainable transport solutions.  The findings underscore the importance of transparency, consistency, and leveraging available data as a reliable foundation for informed decision-making. Additionally, the study highlights the significance of selecting transportation companies that prioritize data utilization and offer green transportation alternatives. Additionally, staying updated on innovations within the field is vital, considering the dynamic nature of the transport industry and the potential for emerging technologies to reshape emission reduction strategies. It is important to note that while short- and long-term recommendations are provided, the ever-evolving landscape necessitates flexibility and continuous adaptation.

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