No description available.

With the increased prevalence of roundabouts in the United States, there is a need to evaluate the performance of roundabouts relative to other intersection control strategies. Few studies have compared roundabouts with other intersection control strategies in a systematic fashion. Consequently, this Thesis compares four types of intersection control strategies considering a single lane approach with a 58 km/hr speed limit and equal demand on all approaches. The study demonstrates that vehicle delay is minimized with the use of a roundabout intersection control for all demand levels below 500 veh/hr/approach. Above this point if the left turn percentage exceeds 70% traffic signal control is more efficient. The roundabout alternative also produces the fewest vehicle stops for low demand levels, low left turn demand and high right turn demand, however a TWSC alternative produces the least number of vehicle stops when the through and total demand is high. This study illustrates that fuel consumption and carbon dioxide, carbon monoxide, hydrocarbon and nitrogen oxide emissions can be improved with roundabout control over other intersection control strategies. The research presented here demonstrates that for low traffic demand levels roundabouts should be part of design alternatives considered for isolated intersection control. / Master of Science

From the 1960s to the 1980s, many schools throughout the country installed synthetic flooring in indoor gymnasiums that contained mercury which was used as a catalyst in the polyurethane formulation. Many of these floors now have been found to be releasing mercury vapors into the school gymnasiums, leading to a concern that these mercury concentrations might be elevated enough to cause harmful effects. This paper examines data that have been collected from 57 different school gymnasiums using portable devices, such as the Lumex RA-915+ Portable Mercury Vapor Analyzer, and aggregated for analyses, then compares this data to that obtained in chamber tests performed on samples obtained directly from a gymnasium with mercury-containing floors. The overall objective of this paper is to determine if the chamber tests can adequately emulate mercury emissions in school gymnasiums, and using the results of the laboratory experiments, successfully analyze the emissions curve to determine what factors drive the profile. The laboratory testing was successful in emulating the condition of a school gymnasium, as data collected from the laboratory setting was comparable to the measured field data. The average mercury concentration in the gymnasium yielded an emission rate 3.1E-05 ug/m2s, while the calculated laboratory emission rate was 3.2E-05 ug/m2s, a negligible difference. The overall objective was met, as it was determined that floor samples taken from a gymnasium could be measured in the laboratory with similar results to those screened in the actual gym with handheld devices. Additionally, using the data collected in the chamber experiments, the emissions profile was characterized. / Master of Science

ENGLISH ABSTRACT: This research report aims to determine whether an emissions trading scheme or carbon tax is the most suitable market-based emissions reduction mechanism for South Africa, given its multiple environmental, social and economic objectives. Key factors considered in this comparison include: environmental effectiveness; economic efficiency; social welfare impacts; public finance considerations; administrative complexity and costs; and, finally, the relationship to global greenhouse gas reduction mechanisms. These factors are compared in the short and long term to determine which mechanism is most likely to deliver South Africa’s emissions reduction targets within the given time frames. The comparison of these factors involves a non-empirical literature review, followed by a rating of the mechanisms in order to distil a best fit in terms of the various aspects of an effective emissions reduction mechanism, taking into account the specific needs and conditions of South Africa. The research found that, in the short term, a carbon tax was best suited to the South African context. This is because of the fiscal certainty inherent in this mechanism, which provides clear price signals and a stable public income. However, the reasons for these comparative advantages over an emissions trading scheme relate to the long lead times and structure of the latter mechanism, which requires years of implementation and favours environmental effectiveness over economic efficiency. Further reasons include a lack of understanding and buy-in in terms of market-based mechanisms, a situation that favours familiarity over effectiveness in some instances. Taking these issues into account, the research shows that an emissions trading scheme is better suited to the South African context in the long term. Once properly implemented, this mechanism provides superior results in terms of the above-mentioned factors, and specifically in terms of environmental effectiveness and the potential for benefit through international integration. This research report concludes that the South African government has failed to take a long-term view of the mechanisms available for emissions reduction, choosing instead to implement a carbon tax, which favours economic growth at the expense of the environment and future generations. A general lack of understanding of the structures and opportunity costs of the two mechanisms necessitates an investigation by government of the applicability and structure of an emissions trading scheme in the South African context before market-based mechanisms can play an effective part in the future development of the country’s environmental regulatory regime.

Indoor sources of air pollution generate a large fraction of overall human exposure to airborne pollutants. Materials used in buildings have been shown to be a major contributor to indoor air pollution, with green building agencies setting guidelines limiting their primary emissions. However, such guidelines neglect secondary emissions resulting from chemistry occurring in indoor spaces. Furthermore, limited knowledge exists regarding ozone reactions and green building materials. This study focuses on the primary aldehyde emissions, ozone deposition velocity, and secondary emissions from three green building materials: recycled carpet, sustainable ceiling tile, and low-VOC paint and primer on recycled drywall. Ozone reactions resulted in secondary aldehyde emissions ranging from no increased secondary emissions to 237 µg m-2 hr-1. Modeling results suggest that these emissions can cause concentration increases beyond odor thresholds. / text

This thesis characterizes the mass and chemical composition of the fine particle air pollution over several cities in South Asia and quantifies how major sources impact the observed levels by using Chemical Mass Balance modeling with organic compounds as tracers. During February 1999, as part of the INDOEX program, a study was conducted to measure the size distribution and chemical composition of the fine particles in a remote island in Maldives off the coast of India. We found that the fine particle concentrations were comparable to those found in major cities in the United States, and were surprisingly high for a background site. 10-day backwind trajectories pointed the source region towards the Indian subcontinent; other INDOEX studies confirmed the presence of a thick haze layer over the Indian Ocean and the subcontinent during the time of the experiment. Motivated by these findings, a detailed analysis of ambient PM2.5 was carried out in Delhi, Mumbai, Kolkata, and Chandigarhfour cities located upwind of the island in Maldives. Seasonality of the fine particle concentrations was observed in each of these cities with the highest concentrations occurring during the wintertime and the lowest concentrations during the summer. Size distribution and chemical composition of the fine particle emissions from five Bangladeshi biomass (rice straw, coconut leaves, dried cow dung, synthetic biomass log, and jackfruit wood) and three Asian coals (Bangladeshi, Indian, and Chinese) were characterized and important source signatures were identified. Finally, recently developed chemical tracer techniques were applied to the ambient samples from North India to differentiate between the contributions from the many different source types. The emission profiles and source signatures from the source tests conducted previously along with the ones conducted using the Indian Subcontinent fuels were used as inputs to the model. These results serve several purposes. First, they provide a description of the mass and detailed inorganic and organic chemical characteristics of fine particulate matter conducted for the first time ever in this region. Second, the source apportionment study will help to define the relative importance of those sources that should be included within an air quality control program. Chemical tracer techniques are particularly attractive for application in regions that have not been studied previously because they are able to yield rapid insights into the causes of a local air pollution problem before the completion of an accurate emissions inventory. Third, the source tests results will prove useful in constructing and evaluating regional emission inventory and assessing source impacts on air quality. Fourth, this work has been carried out with collaborations from Georgia Tech and several other Indian research institutions where pollution control personnel in India was trained in the operation of air sampling equipments that were left for continued monitoring, thus contributing to technology transfer and knowledge transfer from the US.

Deforestation contributes approximately 20 percent of global annual carbon dioxide (CO2) emissions. Increased CO2 is thought to contribute to increased global temperatures. Proposals have been brought forward to use carbon finance to compensate developing countries for reducing emissions from deforestation and degradation (REDD). International negotiations at the UN Climate Change Convention in Copenhagen in December 2009 will determine if REDD Offsets will be included in a post-Kyoto Protocol framework. At the time of writing, Canada proposes to achieve a 20 percent reduction in greenhouse emissions below 2006 levels by 2020 through an intensity based cap-and-trade scheme. International forestry-based offsets are specifically excluded from the proposed Canadian regulatory scheme. The international demand for REDD Offsets will likely grow with acceptance under the proposed US scheme, and others. With proper regulations, international REDD Offsets could be included in the proposed Canadian regulatory system providing benefit to regulated entities and the developing world.

This thesis handles the need for Volvo Logistics (VLC) to calculate their total carbon footprint of purchased transportations, i.e. the total carbon dioxide emissions by all vehicles employed by VLC to transport the goods of their customers. The purpose of the thesis is therefore to determine a method with which VLC can calculate the total carbon footprint. To be able to decide upon one method that can fulfil the purpose, the authors searched for various methods, both in the academia and within the transportation sector, with which the emissions can be determined. Simultaneously the available input at VLC was studied to determine what type of method would be best suited to the current state of the company. After gathering several methods and determine what input was available and what was not available at VLC, an analysis of the found methods was done. First matching them with the available input to see which were usable as is, and then a more thorough Analytical Hierarchical Process analysis using three main-criterions; credibility, comparability, and simplicity, each with several sub-criterions. The weighting of these criterions was done in a workshop together with VLC employees, particularly the Environmental Manager and an Environmental Analyst, but also with two employees at the Global Logistics Development department at VLC. Using the weighting and the author’s comparisons of the methods within each of the criterions it was possible to obtain the methods with which further analysis should be done. After further analysis was conducted, considering VLC’s situation and possible development, the final methods was decided upon, one for each mode of transport; air, rail, road, and sea. These had to be adapted to better suit VLC and the input that was available; the distances, the weight, and the transport mode, factors which are incorporated in the methods recommended by the authors. The adaptation was then done using expertise at VLC to be able to determine what input VLC could affect as to be able to work towards lowering the total carbon footprint once it was calculated the first time. This also led to a revaluation of the method for sea transportation, forcing a change from the previously chosen one to a more suited method. This meant that three of the four modes; air, road, and sea, was covered by the NTM method, while rail used the Green Cargo method. While adapting the methods; to make them ready to use for VLC, certain changes required to obtain all the input needed was encountered and forwarded to the environmental department, letting them include it in the annual supplier survey. The thesis was concluded by four sets of instructions to be used to calculate the carbon footprint, one two tiered set for each mode of transportation. The instructions are presented in a step by step fashion of how to perform the calculations. The first part; First time usage, depicts those changes needed before the calculations can be attempted, the second part; Annual usage, cover those steps which has to be gone through every time the total carbon footprint for a period is to be calculated.

Thesis (LL.M.)--University of Toronto (Canada), 2005. / Includes bibliographical references.

Les entreprises sont, de plus en plus, poussées à analyser leurs émissions de carbone. Notre recherche s’intéresse donc à celles-ci quand elles sont dues au transport et au stockage le long de la chaîne logistique. Pour ce faire, nous avons développé un modèle utilisant la simulation à événements discrets. L’outil proposé modélise une stratégie de réponse à la demande et coordonne les flux en Make To Stock. Trois paramètres variables sont pris en compte : la performance industrielle avec l’utilisation d’un taux de rendement synthétique, la localisation des entreprises et le type de produits fabriqués. Différents scénarii, à politique industrielle et localisation soit homogène soit dégradée soit quelconque et à type de produits différents sont simulés. L’objectif est de comparer les critères environnementaux (émissions de carbone) mais aussi financiers (niveau de stock, kilométrage) de ces configurations. Cette méthode est appliquée aux secteurs mécanique et plasturgique. Les principaux objectifs de l’étude sont les suivants : développer des références pour la simulation de chaîne logistique et conduire des expériences pertinentes afin d’optimiser les chaînes logistiques vertes. / Rendering the supply chain more eco-friendly is an innovative idea progressively adopted by industry. Our research focuses on the CO2 emissions along the supply chain due to freight energy use and storage. A supply chain approach by using a discrete event model was developed. Our proposed tool is able to model Re Order Point production management policy (ROP). Moreover, it can consider the main demand response strategy Make To Stock (MTS). Manufacturing capability is also taken into account using an Overall Equipment Effectiveness indicator (OEE). In addition, the location of the firms and their type of products are modeled. Simulations were conducted by varying the manufacturing capacity, the type of product and the firm location in MTS environment and a ROP planning policy. The purpose is to compare supply chain CO2 emissions and financial elements of different configurations. This method is applied to mechanical and plastic industries. The principle objectives of the study are twofold: develop a supply chain simulation benchmark and conduct pertinent experiments to improve green supply chains.