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This research has examined the application of machine learning and statistical methods for developing roadside particle (number/mass concentrations) prediction models that can be used for air quality management. Data collected from continuous monitoring stations including pollutants, traffic and meteorological variables were used for training the models. A hybrid feature selection method involving Genetic Algorithms and Random Forests was successfully used in selecting the most relevant predictor variables for the models from the variables selected based on their correlation with the PM\(_+\), PM\(_{2.5}\) and PNC concentrations. The study found that the hybrid feature selection can be used with both statistical and machine learning methods to produce less expensive and more efficient air quality prediction models. Among the machine learning models studied the Boosted Regression Trees (BRT), Random Forests (RF), Extreme Learning Machines (ELM) and Deep Learning Algorithms were found to be the most suitable for the predictions of roadside PM\(_+\), PM\(_{2.5}\), and PNC concentrations. The machine learning models performed better than the ADMS-road model in spatiotemporal predictions involving monitoring sites locations. Moreover, they performed much better in predicting the concentrations in street Canyons. The ANN and BRT were found to be suitable for air quality management applications involving traffic management scenarios.

A possible way to continuously monitor the whole water distribution system is to equip pipes with many microsensors. If these sensors are to be integrated within the pipe walls, it is important to assess their impact on the structural integrity of the pipes. In order to test a large number of samples, small polyethylene samples were produced using compression moulding and tested in different stress modes such as tension, bending, Charpy impact and flexural creep, with respect to different chip sizes (4 and 16mm\(^²\)), shapes (circle and square), numbers (one and two), orientations and position as well as sample dimensions and chip-polyethylene interface. It was discovered that the square chip contributes to the highest increase in the polymer stiffness, but significantly reduces its ductility. The 4mm\(^²\) circle causes the smallest disruption in the polymer integrity, especially when including multiple chips and when there is no adhesion. It significantly improves the impact resistance, while its effect in the short and long term bending stress modes is insignificant. The 16mm\(^²\) circle perpendicular to the load direction failed in bending at large strains. The optimal chip orientation for improving the impact strength and reducing the embrittlement effect in tension is parallel to the applied load.

In roadway projects, design exceptions are implemented when the project site consists of one or more substandard design elements. The objective of this thesis is to conduct an initial investigation for a monitoring program for the safety performance of design exceptions in Georgia. A total of 467 projects containing design exceptions were reported in Georgia from 1995 to 2011, and from this crash data for 179 projects from 2003 to 2008 were sampled. The crash data collected in this research pertains to all roadway segments within the projects and is not necessarily related to the design exceptions. Future efforts will be required to explore potential connections between the crash rates and design exceptions. The annual crash results generally revealed a high variability and randomness in the data. For this reason, the average 3-year crash frequencies before design exception approval date and after it were calculated to determine the safety performance for projects containing design exceptions. A method for determining expected results using the Highway Safety Manual (HSM) predictive method is also discussed. The findings will be used to guide future research on design exceptions and mitigation measures to improve roadway safety.

Transportation planners are often faced with the problem of estimating passenger and freight flows between regions. In the literature there are many models for passenger flows. However, models about freight flows are more limited. Modeling freight flow is also more complex than modeling passenger flow and there are many agents related with freight flows. In addition, data availability is a critical factor. In this research, freight flows between provinces in T&uuml / rkiye are forecasted by demand analysis. Transportation is one of the important activities of human beings and plays an important role for spatial interactions in economic growth. In other words, there is a very strong linkage between economic growth and the freight flow, thus transportation demand. Regional trade as spatial flow appears on transportation systems as freight flows. In this study, using the existing limited data and surveys in T&uuml / rkiye, nationwide origin-destination (O-D) matrix of freight flows between provinces is obtained. Using this empirical matrix, the generation of freight flows of provinces is formulated depending on the socioeconomic and demographic variables by means of multiple linear regression analysis. In addition, interactions of freight flows between provinces and economic growth of regions are investigated. The generations and attractions of provinces as freight flow are distributed between provinces with traditional gravity model. By comparing observed O-D matrix and simulated O-D matrix, gravity model is calibrated. Calibration is also performed by freight trip length distribution. In this research, two steps of traditional &ldquo / four-step analysis&rdquo / , &ldquo / trip generation&rdquo / and &ldquo / trip distribution&rdquo / , are applied to develop nationwide freight demand model between the provinces in T&uuml / rkiye. The developed model is single-mode, single commodity and nationwide.

published_or_final_version / abstract / toc / Transport Policy and Planning / Master / Master of Arts in Transport Policy and Planning

The economy of Oman, was traditional in character before the development of the oil sector which set in motion the present structural transformation. Economic prosperity gave the opportunity to the public to possess their own private means of transport, thus resulting in a rapid increase in the number of vehicles in the country, particularly in the Muscat Area the capital city of the country. Free essential services such as health and education, and no taxes and duties have led to high disposable household income. Therefore, Muscat is witnessing rapid and successive land-use changes, expansion of the urban area and multi-car owning households. In the last two decades the population of Muscat increased considerably. This population growth was accompanied by a substantial expansion of Muscat's boundaries to provide homes, work places and other facilities. The topographical nature of the area limited the flat land available for housing, shops, schools, and other elements of the infrastructure. The resulting competition for space had as one of its consequences that insufficient land was allocated for car parking in the major activity centres, and the result was an acute shortage of parking spaces in these areas. The expansion of the Muscat Area was accompanied by changes in the employment and residential pattern. This resulted in a significant increase in number of vehicles, trips and commuting, and so the need for effective transport services and facilities became greater than ever before. The topographical features made it more difficult to provide sufficient transportation facilities. Development planning neglected the importance of arranging urban activities in such a way that the need for vehicle movements would be greatly reduced. It also resulted in low density population areas with street patterns mostly not designed for public transport services. This study sets out to discuss the problems of urban transportation in the Muscat Area and seeks to answer the following questions: What are the trip characteristics? How far do the natural topographical features inhibit the development of the Muscat road network? How does the existing network serve the needs of the area? How far can it cope with the traffic movement? Will the proposed major roads solve the present problems of traffic congestion and alleviate future ones? What are the main causes for traffic accidents? To what extent are car parking facilities adequate at the major activity centres? What is the role of Oman National Transport Company buses within the public transport system? The Muscat Area faces problems of traffic congestion and accidents, high demand on parking facilities and inadequate public transport. The situation is liable to deteriorate sharply in the next few years, unless effective action is taken. There is a need for a study that can provide immediate practical solutions and propose guidelines for future policy to ensure that the transport system is expanded and improved to cope with the needs arising from future growth. This study identifies factors contributing to the existing traffic problems with the intention of providing useful information which can help traffic planners and decision makers in understanding the nature of the problems, and finding solutions and guidelines for future policy. As far as methodology is concerned, a literature review is supported by fieldwork involving questionnaires and contacts with relevant authorities. Four types of surveys were conducted in order to collect information that can identify some of the factors that are contributory to the present problems. On the basis of the analysis of the data collected, urban transport problems are identified and discussed together with some possible solutions and recommendations.

Gravel filters are potentially a low cost, low maintenance water treatment solution. They require no mechanical or electrical parts and can operate without the addition of chemicals or the need for close supervision. As such, they are an appropriate technology for treating road runoff as a component of Sustainable urban Drainage Systems (SuDS) and as an initial stage of drinking water treatment in rural areas. However, the processes by which pollutant particles are removed in gravel filters are poorly understood and practical experience shows that many filters fail long before their expected design life is reached. For this reason gravel filters are little used for drinking water treatment and, when they are incorporated into SuDS, their removal efficiency and maintenance requirements are unpredictable. The aim of this thesis was to better understand particle removal processes and the implications for gravel filter design. This was achieved through a combination of lab-based experiments and numerical modelling. • The change in conservative tracer transport characteristics with pollutant particle accumulation was assessed through column experiments. • The spatial heterogeneity of particle accumulation was measured by collecting 3D data with magnetic resonance imaging (MRI). Multiple scans of filters allowed the temporal evolution of particle accumulation to be assessed. A method for processing the raw MRI data to yield the change in 3D pore geometry was developed, assessed and applied. • A simple method for extracting and comparing pore network characteristics at different stages of particle accumulation was applied to the MRI derived geometry. • Direct modelling of the 3D MRI pore geometry with the open source software OpenFOAM allowed correlation of flow velocities with particle accumulation at each point in the pore network. Lagrangian particle tracking was used to simulate the transport of a conservative tracer through the filter. Key findings were that spatial heterogeneity in particle accumulation was influenced by both initial pore geometry and the temporal evolution of the pore network with accumulation. This was attributed to the formation of high velocity preferential flow paths that were evident in both the 3D MRI data and the numerical model of that data. Pore networks exhibited a decrease in connectivity with accumulation and this was mirrored by a decrease in the volume of the filter that was accessible to a conservative tracer. Conclusions of this thesis are that MRI is a useful tool for non-invasively assessing the spatial variability of clogging in gravel filters and, when combined with numerical modelling of the pore geometry, for establishing the link between pore velocity and particle removal. The formation of preferential flow paths is detrimental to the pollutant removal efficiency of a filter and could explain why many filters fail to produce good quality effluent well before their physical pollutant storage capacity is reached.

Today, the information (signal timings, detector extension, phase sequence, etc.) to install traffic lights on the street are obtained from traffic software simulations platforms, meaning that information from simulation is not tested on the field (intersection where it will be installed) before the installation. Many installed controllers on the street use time of day (TOD) patterns due to cheaper cost than adaptive traffic control systems, but that is not the best solution for traffic volume changes that can occur during the day or even a month. To improve traffic signal operation most of the traffic signal controllers in the same corridor or zone operate in coordination mode. Furthermore, phases need to be in coordination to achieve “green wave”. Green wave is term used when in corridor traffic lights allow continues flow of traffic through intersections that are coordinated. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection

劉淳. / Thesis (doctoral)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (p. 214-228). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in Chinese and English. / Liu Chun.