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This thesis examines factors that influence the daily number of trip departures and arrivals at over 100 hubs comprising Hamilton, Ontario’s (Canada) bike share program – SoBi (Social Bicycles) Hamilton. SoBi operates all year, and during its first year of operation (April 1, 2015 to March 31, 2016), over 200,000 trips were generated on SoBi bikes. The study utilizes data from SoBi Hamilton, the 2011 Canadian Census, the 2011 Transportation Tomorrow Survey, Environment Canada, and Hamilton’s Open Source Data initiative. From these master files, daily trips, meteorological data, temporal variables, socio-demographic and built environment attributes were obtained to generate a comprehensive suite of explanatory variables to explain the daily trips at each hub. A multilevel regression approach was used to understand the associations between bike share usage at each hub and each suite of explanatory variables at two temporal scales: total daily trips at hubs and total daily trips across four time periods of the day. Findings demonstrate that weather and temporal attributes play a significant role in trip departures and arrivals. In addition, hub attributes vary in significance throughout different times of the day for trip departures and arrivals. Overall, the methodology and findings allow us to identify factors that increase SoBi usage, which can also benefit city planners and engineers who are implementing a bike share system with the goal of maximizing bike share activity in urban centers. / Thesis / Master of Science (MSc)

This study is concerned with the problem of locating p capacitated facilities on a chain graph, and simultaneously determining the allocation of their supplies in order to satisfy a continuum of demand which is characterized by some weighted probability density function defined on the chain graph. The objective is to minimize the total (expected) transportation cost. This location-allocation problem is also referred to as the capacitated p-median problem on a chain graph. Two unbalanced cases of this problem are considered, namely, the over-capacitated case when total supply exceeds total demand, and the deficit capacity case when total supply is less than total demand. Both these problems are nonconvex, and are shown to be NP-hard even if the demand density function is piecewise uniform and positive. We provide a first-order characterization of optimality for these two problems, and prescribe an enumerative algorithm based on a partitioning of the dual space in order to optimally solve them. An extension of these algorithms for solving the capacitated, unbalanced 2-median problem on a tree graph is also given. / M.S.

Thesis advisor: Michael Grubb / Thesis advisor: Charles Murry / This dissertation consists of two self-contained papers that explore the Industrial Organization of the UK television broadcasting market and broadband procurement by US K-12 schools Chapter 1: Welfare Effects of Competition in the UK Television Broadcasting Market In this chapter, I study the consumer welfare effects of a regulation that ended the exclusivity of telecast rights of live English Premier League games and induced entry into the UK television broadcasting market. Historically rights were owned by a single broadcaster. The regulation divided the games into mutually exclusive bundles and stipulated that a single broadcaster cannot own rights to all of them. This resulted in a new channel entering the market and showing some games. I estimate a model of household viewing preferences, channel subscription demand, and pricing using proprietary viewing and subscription choice data. Simulations show a 6.4\% (\pounds 10m per season) decline in consumer surplus driven by the higher prices consumers had to pay to view all the live games. This offset increased surplus from new content on the entrant channel. I propose an alternate regulation that breaks the exclusivity of games telecast on a channel and show that the estimated surplus could have been 29\% higher. Chapter 2: Bundling Demand in K-12 Broadband Procurement In this chapter coauthored with Gaurab Aryal, Charles Murry and Pallavi Pal, we evaluate the effects of bundling demand for broadband internet by K-12 schools. In 2014, New Jersey switched from decentralized procurements to a new procurement system that bundled schools into four regional groups. Using an event study approach, we find that, on average, prices for participants decreased by one-third, and broadband speed purchased increased sixfold. We bound the change in school expenditures due to the program and find that participants saved at least as much as their total ``E-rate" subsidy from the federal government. Under weak assumptions on demand, we show that participating schools experienced large welfare gains. Using an informal model and simulations, we analyze the main mechanisms that could lead to lower prices in the regional auctions. / Thesis (PhD) — Boston College, 2024. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Economics.

The dominant ideology within the illegal immigration discourse in the US primarily faults illegal workers for the problem by highlighting the act of illegally entering the US as the origin of the problem. As the dominant ideology goes, illegal immigrants evade law enforcement at the border; they deceive employers to secure work. They disrupt labor markets by lowering wages which displaces lower class US workers. The illegal immigrants and their families abuse social services that they do not pay into at the US taxpayers expense. They form ethnic enclaves, and those who remain in the US resist assimilation into US culture. So the story goes. This thesis challenges this dominant ideology, a subset of the illegal immigration discourse, by documenting decades of immigration law in the US created to serve US employers' demand for labor, and alternately, closing the immigrant worker pipeline when it suited the government's political objectives or the special interests of employers. Loopholes in the immigration laws have tended to insulate employers from prosecution. Meanwhile, undocumented workers have faced lower wages and increased risk. This thesis examines what constitutes the dominant ideology of the illegal immigration discourse. It also includes a discourse analysis of illegal immigration by reviewing national, regional, and local media coverage of the simultaneous raids in December 2006 of six Midwest meat processing plants operated by Swift & Company. The discourse analysis explores media coverage of the raids conducted by the Department of Homeland Security's Bureau of Immigration and Customs Enforcement (ICE). The raids led to the arrest of 1,282 suspected illegal immigrants, and the analysis will attempt to understand to what extent media coverage supports or challenges the dominant ideology of the illegal immigration discourse. / Master of Arts

The Available Bit Rate (ABR) service class for the Asynchronous Transfer Mode (ATM) protocol was originally designed to manage data traffic. ABR flow control makes no guarantees concerning cell transfer delay or cell delay variation. A closed-loop feedback mechanism is used for traffic management. To use this class of service for video transport, the video source will accept feedback from the network and adapt its source rate based on this status information. The objective of this research is to assess the ability of the ATM ABR service class to deliver Moving Picture Experts Group version 1 (MPEG-1) video. Three approaches to source-level control are compared: (i) arbitrary loss or no control method, (ii) selective discard of MPEG B-pictures, and (iii) selective discard of MPEG B- and P-pictures. Performance is evaluated based on end-to-end delay, congested queue occupancy levels, network utilization, and jitter. A description of the investigation, assumptions, limitations, and results of the simulation study are included. / Master of Science

Population growth and climate change have strained existing water supplies requiring municipalities to shift towards demand management strategies to ensure reliable water provisions. Particularly in the residential sector, water conservation measures and incentives have been utilized to reduce demand during short-term shortages. As water conservation programs are now being commonly utilized as a way to ensure enough water will be available for continued growth, the impacts on a basin-wide scale have yet to be established. By changing the relative water demand for indoor and outdoor uses within a municipality, the amount of water being consumed can thereby reduce the effluent available for downstream communities. This research investigates how the timing of water conservation, water conservation strategy, and population growth impact water availability in a shared basin. A generalized system dynamics model reflecting typical residential water use and availability patterns similar to the southwest United States was utilized. We found that when upstream municipalities focus their initial reductions on non-consumptive demands, downstream municipalities reliant on upstream return flow have to increase their conservation rate to meet demands and maintain population growth. When most of the basin's population is in upstream municipalities, the more influence their change in water use has on downstream water availability. Therefore, consumptive conservation should be the priority of basin-wide conservation programs to ensure return flow is sufficient to satisfy the demands of downstream municipalities. / Master of Science / Population growth and climate change have reduced water supplies for many cities across the United States. This has led to increased water conservation at the household level to reduce the amount of water needed for everyday uses. Efforts like reduced lawn watering and shorter showers have been helpful during short-term dry spells but more cities are using long-term strategies like high efficiency appliances and the removal of green lawns to "free up" enough water for population growth. However, these changes in water use can impact how much water returns to the river and goes downstream for the next city to use. This research looks at how changes in the speed of water conservation, water conservation strategy, and population impacts water availability in a shared basin. Our stylized model reflects typical residential water use and availability patterns similar to the southwest United States. We found that the faster cities within a basin reduce their indoor water use, the greater downstream cities have to reduce their water use in order to have enough available water to meet demands. Also, when most of the basin's population is in upstream cities, the harder it is for the downstream city to have enough water to maintain target population growth. However, reducing outdoor water use first is the best way for every city that shares the same river to stay satisfied.

The problem of this study is to determine what are the factors associated with teacher supply and demand in Texas, to analyze and interpret these factors, and to offer recommendations regarding the problem.

The research presented in this report is in two sections. Section I involved the performance of a moving bed biofilm reactor (MBBR) versus a biological aerated filtration (BAF) and Section II involved study on causes of deposition in anaerobic digester gas piping. The first section evaluated and compared the performance of a laboratory-scale MBBR and BAF for organic carbon and suspended solids removal. A kinetic study was also performed on the MBBR to evaluate the system performance. The purpose was to recommend one of the systems for the Force Provider project, which provides a containerized "city" for the U.S. Army. The effluent criteria against which the systems were evaluated were total 5-day biochemical oxygen demand (TBOD5) and total suspended solids (TSS) of 30 mg/L each. The report is based on a 5-month laboratory -scale study of the two reactors. The MBBR performance depended on the percent of media provided in the reactor and the organic loading. At a media volume, which displaced the reactor volume by 40 % (heretofore called 40 % media volume), and surface area loading rate (SALR) of 20 g BOD5/m2-d, the system performance deteriorated with time. At 40 % media volume and SALR below 15 g BOD5/m2-d, the system performance improved but still did not meet effluent criteria or average. TBOD5 reduction was generally poor (approximately 50 %). Soluble BOD5 (SBOD5) concentrations were frequently below 30 mg/L and TSS concentrations were often higher than influent TSS. Overall, TSS wastage from the system (both effluent TSS and intentional wastage) averaged 0.032 kg/d. BAF system performance was excellent for TBOD5, CBOD5, SBOD5 and TSS removal, and were consistently less that 30 mg/L. Overall TSS wastage from the BAF (both via effluent and backwash) average 0.027 kg/d and was 16 % less than for the MBBR. Based on demonstrated performance, the BAF was the only viable reactor for the project. Section II of the report focused on possible causes of deposition in an anaerobic digester gas piping at a local wastewater treatment facility (Peppers ferry regional wastewater treatment facility). Industrial waste input to the treatment facility has increased lately and accounts for 40 % of the plant's wastewater inflow. An industry in Pulaski, VA, Magnox Inc. generates and disposes highly concentrated sodium sulfate, (70,000 mg/L) which is a by-product of its activities, to PFRWTF wastewater influent stream. As a result of Magnox industrial waste input, a pilot study was carried out to determine the effect of its waste on the activated sludge treatment units. Results indicated that Magnox industrial waste input would not have adverse effect on the aeration basins. However production of H2S, which can have effect on the anaerobic digester was reported (Olver Inc., 1995). Field analysis of data reported by Olver Inc. (2000) showed that H2S concentration in PFRWTF anaerobic digester gas was rising. X-ray photoelectron spectroscopy analysis of deposits found in the digester pipe together with results obtained from the laboratory-scale study revealed that iron and sulfur played a role in the deposition in the digester gas pipe. The laboratory scale study revealed that ferrous ion in the digester feed possibly precipitated over 90 % of the hydrogen sulfide gas produced in the digester, thus protecting the digester from adverse effects caused by hydrogen sulfide. / Master of Science