- Solvang, CA
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Queue formation and dissipation have been extensively studied in relation to traffic signalization, work zone operation, incident occurrence, and ramp metering. This study is an attempt to estimate the effect of vehicle mix, commute time,... more
Queue formation and dissipation have been extensively studied in relation to traffic signalization, work zone operation, incident occurrence, and ramp metering. This study is an attempt to estimate the effect of vehicle mix, commute time, traffic direction, and road upgrade on queue dissipation speed (time). The data were collected at several intersections in Davis, California, U.S. and analyzed using regression models. The models were determined regressing several functional forms and considering the statistical significance and ease of interpretation of the included variables. The main findings are: 1) dissipation speed does not vary purely by location; 2) a heavy vehicle is faster to discharge than its passenger car sizeequivalent is; 3) the queue in a left-turn lane discharges faster than that in a through lane; 4) an upgrade slope increases the queue dissipation time due to more rolling resistance to vehicle start-up and larger vehicle gaps for safety ; 5) morning queues genera...
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Network design problem has been, and is, an important problem in transportation. Following an earlier effort in designing a meta-heuristic search technique by an ant system, this paper attempts to hybridize this concept with other... more
Network design problem has been, and is, an important problem in transportation. Following an earlier effort in designing a meta-heuristic search technique by an ant system, this paper attempts to hybridize this concept with other meta-heuristic concepts such as genetic algorithm, simulated annealing, and tabu search. Seven hybrids have been devised and tested on the network of Sioux Falls. It has been observed that the hybrids are more effective to solve the network design problem than the base ant system. Application of the hybrid containing all four concepts on a real network of a city with over 2 million population has also proved to be more effective than the base network, in the sense of finding better solutions sooner.
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Research Interests: Engineering, Environmental Engineering, Civil Engineering, Environmental Science, Computer Science, and 15 moreEconomics, Development Economics, Climate Change, Asset Pricing, Environmental Studies, Climate change policy, Environmental Management, Consumer Behavior, Ecology, Congestion Pricing, England, Economia, Cost Benefit Analysis, Civil and Environmental Engineering, and Electronic Road Pricing
Abstract Two major extreme-weather events occurred in New York State between 2011 and 2012. Each with the odds of a 100-year occurrence suggesting that such extreme events are the region’s “new normal.” City and state policy-makers, in... more
Abstract Two major extreme-weather events occurred in New York State between 2011 and 2012. Each with the odds of a 100-year occurrence suggesting that such extreme events are the region’s “new normal.” City and state policy-makers, in response, are studying how to develop a network of robust, resilient critical infrastructure facilities. These studies, however, typically fail to address interdependencies among critical infrastructures and lack a quantitative tool to investigate the maximum resilience possessed by a given infrastructure facility in the face of climate-change-induced hazards. We propose a multi-stage stochastic mathematical program to maximize network resilience given: i ) random arrival of extreme events; ii ) the network’s inherent capacity to withstand and cope with the aftermath of exogenous shocks; iii ) pre-, during-, and post-event strategies available to enhance system operability; and iv ) budgeting and technological restrictions facing policy-makers. Our approach allows both qualitative and quantitative paradigms to interact. Our model thus clarifies how to allocate resources proactively and how the network’s absorptive, adaptive, and restorative capacities can be coordinated to enhance overall system resilience. Our findings suggest that an integrated planning approach combined with smart allocation of resources across a network’s main elements creates a greater degree of resilience while utilizing less costly resilience-enhancing strategies.
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Sustainable transport commonly considers either the interaction between built and natural environments or the interface between transportation and interdependent critical infrastructure. Although considering each of these key dimensions... more
Sustainable transport commonly considers either the interaction between built and natural environments or the interface between transportation and interdependent critical infrastructure. Although considering each of these key dimensions is a crucial task for achieving sustainable transport, the dimensions are infrequently considered together. When an integrated network design framework is proposed, two important issues are taken into account: (a) the aftermath of potential severe weather episodes on metropolitan-area infrastructure and (b) the existing interdependencies across transportation and fuel supply chain networks. Then the response of infrastructure in the face of flooding hazards is investigated. Framed within a multistage linear stochastic program, the proposed model seeks to find fueling station deployment that provides the transportation network with optimum random functionality when the network is stressed or under attack. A set of numerical experiments illustrates how changes to enhancement strategies at different stages of government affect the optimal investments in resilient design.
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Research Interests: Management, Finance, Engineering, Civil Engineering, Transportation Engineering, and 15 moreEconomics, Public Administration, Social Sciences, Research Methodology, Project Management, Political Science, Sustainable Development, Strategic Management, Consumer Behavior, Modeling and Simulation, Public Private Partnerships, Social Welfare, Privatization, HIGHWAY ROADS AND BRIDGES, and Public Policy
ABSTRACT Public–private partnerships (P3s) are likely to impact entire transportation systems in fundamental ways. However, few studies have examined the potential impact of P3s on large-scale transportation networks. These studies have... more
ABSTRACT Public–private partnerships (P3s) are likely to impact entire transportation systems in fundamental ways. However, few studies have examined the potential impact of P3s on large-scale transportation networks. These studies have focused on modeling rather than on policy analysis. The literature thus does not offer guidance for designing and administering P3s to improve transportation system performance while maintaining profitability. Using Fresno, California's transportation network as a laboratory, we consider the effects of alternative P3 tolling approaches on profit maximization and system performance optimization at full urban transportation network scale. Based on system modeling results, we offer the following recommendations for policy makers to design and promote successful P3s in urban settings: (i) to promote a profitable and a socially beneficial system, toll rates should be set examining both profit-maximizing and system-optimal rates; (ii) even though tolls (i.e., higher travel costs) on a few roads help reduce travel demand they may, counter-intuitively, lead to higher total travel cost for the overall transportation system because of users’ decision to travel longer distances to avoid tolls, especially when high toll rates are applied; (iii) lower limit(s) on tolls (in addition to upper limits) may be required to enforce system-optimal tolling and avoid undercutting by private owners; (iv) a variable tolling approach (i.e., temporally- and spatially-varying tolls) significantly reduces congestion and increases profits relative to flat tolls; and (v) public officials should provide a comprehensive plan regarding past, current, and future P3 projects along with a detailed system-wide impact analysis to promote a more sustainable transportation system.
Research Interests: Business, Management, Finance, Engineering, Civil Engineering, and 15 moreTransportation Engineering, Economics, Political Economy, Social Sciences, Project Management, Operations Research, Political Science, Network Analysis, Modeling and Simulation, Behavioral Economics, Congestion Pricing, Public Private Partnerships, Privatization, System performance, and Public Policy
Fundamental changes in road ownership and pricing have been viewed as possible remedies for the road usage and funding challenges in the transportation sector. To fill the gaps in our knowledge about the choice among different ownership... more
Fundamental changes in road ownership and pricing have been viewed as possible remedies for the road usage and funding challenges in the transportation sector. To fill the gaps in our knowledge about the choice among different ownership structures, we develop a multi-level programming model that integrates system performance and profit maximization, game theory, and modified traffic assignment sub-models. Using this model, we provide a set of policy insights for policy makers. First, toll roads are interdependent in a complex manner since some pairs of roads are substitutes and others are complements, and because such cross effects can be reversed in different time periods and under different own and cross toll rates. Second, each toll road’s profit generally increases when more roads are tolled since roads commonly act as substitutes to each other. With such an insight, policy makers can ensure higher (and/or less risky) profits from toll roads and better deals with private operators of toll roads. Third, a mixture of private and public toll roads could generate significant profits while reducing transportation costs dramatically, thus contributing to sustainability. Finally, a comprehensive long-run transportation plan must investigate various road ownership schemes and examine their impacts on the profitability and the performance of the transportation system as a whole.
Research Interests: Management, Finance, Engineering, Civil Engineering, Transportation Engineering, and 15 moreMathematics, Applied Mathematics, Economics, Transport Economics, Social Sciences, Research Methodology, Operations Research, Transportation Studies, Strategic Management, Networks, Transportation, Economic Development, Privatization, HIGHWAY ROADS AND BRIDGES, and Public Policy
Research Interests: Management, Transportation Engineering, Economics, Political Economy, Social Sciences, and 11 moreAsset Pricing, Political Science, Sustainable Development, Transport Planning, Modeling and Simulation, Qualitative Research, Public Policy - Social Welfare Policy, Social Welfare, Road Pricing, Sustainability, and Public Policy
Studies examining the social cost of driving usually ignore the opportunity cost of having roads in place: the associated land rents. Especially for geographic regions where land is valuable, including the rent costs may even lead... more
Studies examining the social cost of driving usually ignore the opportunity cost of having roads in place: the associated land rents. Especially for geographic regions where land is valuable, including the rent costs may even lead governments to close some roads. By using the London congestion charging zone case, a more general long-run social cost curve is calculated with the addition of the rents. Based on the optimal road usage concept, this study found that including the rents in the cost/ benefit analysis significantly affects the results and can increase the social cost by up to 200% and decrease the optimal road usage by 40%.
The Clean Development Mechanism (CDM) is a program under the Kyoto Protocol designed to help developing countries reduce their greenhouse gas (GHG) emissions. The program was originally adopted to reduce the cost of compliance for Annex I... more
The Clean Development Mechanism (CDM) is a program under the Kyoto Protocol designed to help developing countries reduce their greenhouse gas (GHG) emissions. The program was originally adopted to reduce the cost of compliance for Annex I countries and, as a result, has failed to foster renewable, transportation-related, or small projects. The fundamental question is whether or not the CDM can incentivize sustainable development, especially in terms of GHG reductions, in the ever-growing transportation sector of the developing world. Among the various transportation projects, fuel switch and mode switch projects are the most common options in the CDM, mainly because travel activity, vehicle efficiency and occupancy, and infrastructure investments are too broad for a project-based approach. A sectoral approach or Nationally Appropriate Mitigation Actions (NAMAs) could provide a better fit for transportation policies; however, probably due to its more complex structure, no sectoral transportation option has been approved in the CDM. This paper reviews and critiques the CDM, and considers modifications to improve the program in these contexts.
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The authors examine the effects of New York’s Labor Law 240, known as the Scaffold Law, on worker safety. This law is important because it generates much litigation and significantly increases the cost of infrastructure projects in the... more
The authors examine the effects of New York’s Labor Law 240, known as the Scaffold Law, on worker safety. This law is important because it generates much litigation and significantly increases the cost of infrastructure projects in the state, especially through insurance. Supporters of the 19th century law argue that it enhances worker safety. Critics suggest that it creates moral hazard, or reduced investment in precaution, on the part of workers. The authors assemble the first-ever panel data set across states, time, and economic activities to empirically examine those competing claims. The authors' data set includes 3,382 observations from 2000 to 2010 across 42 states and a variety of commercial activities. Using standard panel data techniques such as year-fixed effects, state-fixed effects, and robust standard errors, the authors found that New York’s Scaffold Law increases both fatal and nonfatal construction accidents. This effect is significant in magnitude, and is consistent with the predictions of standard models of liability rules. The authors conclude their study by examining the effect of Labor Law 240 on insurance loss costs in the state, finding that it significantly increases the cost of infrastructure construction through higher insurance costs, which is also consistent with reduced worker safety. The authors' analysis questions the ongoing efficacy of the law.
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ABSTRACT Almost all road infrastructure is treated as a public good and seen as a governmental obligation. But roads differ from other public goods such as national defense in both non-rivalry and nonexclusiveness features. Moreover,... more
ABSTRACT Almost all road infrastructure is treated as a public good and seen as a governmental obligation. But roads differ from other public goods such as national defense in both non-rivalry and nonexclusiveness features. Moreover, Financing construction and maintenance of road infrastructure is challenging because in most countries, government revenues for road construction and maintenance are insufficient. Here, the idea of road privatization is introduced as a possible alternative. Although there are many political and societal hindrances in implementing this idea, its potential to solve problems in transportation is indisputable. The road owner pays the government for the externalities produced from his property (pollutions or accidents) but can make money by charging users (passing the externalities burden to users, while easing congestion and free rider problems) and because the road is privately constructed and owned, the opportunity cost of the road construction and maintenance is better accounted for. By assigning the road’s property to private sectors, the supply side might become more efficient based on the transformation from a publicly subsidized market to an open market framework. The equity problem of the new pricing scheme can be partially solved with a rebate policy similar to creditbased congestion pricing (CBCP).
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Research Interests: Management, Engineering, Environmental Science, Economics, Energy Economics, and 15 moreSocial Sciences, Climate Change, Renewable Energy, Energy Policy, Geothermal, Modeling and Simulation, Public Health, Renewable energy resources, Environmental Sustainability, Energy efficiency, Electricity, California, Energy Efficiency, Renewable Portfolio Standards, and Public Policy
Abstract Two decades after the collapse of the Soviet Union, Caspian Sea-the largest inland body of water on earth-continues to be the subject of one of the world's most insurmountable disputes, involving Iran, Russia, and... more
Abstract Two decades after the collapse of the Soviet Union, Caspian Sea-the largest inland body of water on earth-continues to be the subject of one of the world's most insurmountable disputes, involving Iran, Russia, and the new sovereign states of Azerbaijan, Kazakhstan, and Turkmenistan. The conflict is over the legal status of this multinational water body, which supplies almost all of the world's black caviar, and holds about 10% and 4% of the world's oil and gas reserves, respectively. Typically, proposed division methods for sharing the ...
In this paper, I briefly review the key methods to evaluate transportation projects. These methods are: Financial analysis; Cost benefit (economic analysis); Multi-criteria analysis; Cost-effectiveness analysis; Social welfare analysis;... more
In this paper, I briefly review the key methods to evaluate transportation projects. These methods are: Financial analysis; Cost benefit (economic analysis); Multi-criteria analysis; Cost-effectiveness analysis; Social welfare analysis; and Risk analysis (Monte Carlo simulation). The importance of understanding these methods lies in the fact that transportation projects offer huge social benefits and costs; some are impossible or very complex to measure in monetary terms.
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AbstractManaged lanes (MLs) offer public infrastructure owners a key policy lever for reducing the financial burden of road expansion while managing induced travel demand. ML’s impact varies depend...
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In this article, I will examine the social welfare effects of implementing High Occupancy Toll (HOT) lanes, and Managed Lanes in general. HOT lanes, in contrast to existing general purpose (GP) lanes, allow motorists to use these express... more
In this article, I will examine the social welfare effects of implementing High Occupancy Toll (HOT) lanes, and Managed Lanes in general. HOT lanes, in contrast to existing general purpose (GP) lanes, allow motorists to use these express lanes if they either pay a toll or have a certain minimum number of occupants in their vehicle. HOT lanes are often implemented by either converting existing High Occupancy Vehicle (HOV) lanes to HOT lanes or by constructing new managed lanes (MLs) in the median strip of an existing highway. They offer two major benefits over HOV lanes: (i) mitigating inefficiencies arising from the underutilization of HOV and GP lanes; and (ii) generating new revenue while preserving user satisfaction. Despite such potential benefits from HOT lane conversions and ML adoption, a comprehensive study rigorously estimating social welfare benefits and costs has not yet been undertaken. This paper reviews and provides a guideline for HOV to HOT lane conversions, form the...
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The low price elasticity of gasoline demand has been shown in different studies. People‟s weak perception about how much they spend on fuel is considered as an important reason. The purpose of this study is to show how information about... more
The low price elasticity of gasoline demand has been shown in different studies. People‟s weak perception about how much they spend on fuel is considered as an important reason. The purpose of this study is to show how information about gas consumption may change people‟s behavior. Congestion pricing has been successful in terms of reducing demand and even changing people‟s decisions. People perceive this pricing as out of pocket cost and take that into account while making decisions. A similar procedure can be implemented for fuel costs. On-line information from transportation networks can be used to estimate the gas consumption cost for each route, using on-road banners or GPS devices. The idea is that as a result of becoming informed about their gas consumption increase when entering traffic congestion, people may take an alternative route or decide not to travel at all. Although it is not possible to estimate the exact change in the price elasticity of gas by introducing this me...
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Congestion is a growing challenge in major urban areas worldwide; a challenge that imposes enormous social and private costs to society. Despite these substantial costs, our knowledge is limited about how transportation users value... more
Congestion is a growing challenge in major urban areas worldwide; a challenge that imposes enormous social and private costs to society. Despite these substantial costs, our knowledge is limited about how transportation users value choices that can reduce fuel consumption, greenhouse gas (GHG), and criteria pollutant emissions (PM2.5, NOx, CO, etc.). In this regard, I proposed the advanced traveler general information system (ATGIS), a scheme that can estimate/provide travelers with travel cost data that they currently do not have. In this paper, I explain the steps required to test, examine, and develop such a scheme for a metropolitan area.
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The major risk associated with the provision of toll facilities results from uncertain future demand/revenue generated from the facilities. In this paper, I examine various options for mitigating toll revenue risk and provide a set of... more
The major risk associated with the provision of toll facilities results from uncertain future demand/revenue generated from the facilities. In this paper, I examine various options for mitigating toll revenue risk and provide a set of recommendations as to how revenue risk mitigation should be pursued. In addition to conducting more careful traffic revenue studies and risk analyses, policy makers can provide more flexible tolling schedules, adopt advanced toll collection technology, and limit the non-compete clause included in many toll road deals with private operators.
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Public Private Partnership (P3) projects are likely to fundamentally impact entire transportation systems. However, most studies are focused on system modeling rather than policy analysis, and few studies have examined the impacts of P3s... more
Public Private Partnership (P3) projects are likely to fundamentally impact entire transportation systems. However, most studies are focused on system modeling rather than policy analysis, and few studies have examined the impacts of P3s on real-size transportation networks. Policy guidance for devising and administering P3 contracts to improve transportation system performance while maintaining profitability is lacking. Using the transportation network of Fresno, a middle-sized city in California as an example, this study considers alternative P3 approaches for profit maximization and system cost minimization at full urban transportation network scales. Based on system modeling results, the authors offer the following recommendations for policy makers to design and promote successful P3 projects in urban environments: (1) to promote a profitable and a socially beneficial system, toll rates should be set between profit-maximizing and system-optimal rates; (2) even though tolls (i.e....
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This paper provides a brief overview of the concept of value of time (VOT), in the context of toll road schemes. VOT analysis determines the tradeoffs travelers make between time and tolls. The analysis is very important when considering... more
This paper provides a brief overview of the concept of value of time (VOT), in the context of toll road schemes. VOT analysis determines the tradeoffs travelers make between time and tolls. The analysis is very important when considering the choice between tolled and un-tolled alternatives. Using travel demand model of Fresno, CA, I provide a sensitivity analysis showing how the outcomes of tolling schemes can change with varying VOT levels.
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Policy makers often evaluate public-private partnerships (P3) projects using Value for Money (VfM) analysis. However, a P3 project’s impact on overall social welfare provides a more comprehensive evaluation criterion. Apart from several... more
Policy makers often evaluate public-private partnerships (P3) projects using Value for Money (VfM) analysis. However, a P3 project’s impact on overall social welfare provides a more comprehensive evaluation criterion. Apart from several theoretical studies, a detailed social welfare analysis that includes all major P3 project stakeholders (residents, users, government, and the private sector) is lacking in the transportation literature. We offer a framework estimating the benefits and costs of using alternative Investment P3 (IP3) approaches. An IP3 returns a significant portion of the value created by road pricing back to the citizen-owners of a newly priced transportation facility in an urban transportation system. A major policy insight from our study is that system-optimal tolling scenarios favor average users, but government – and consequently taxpayers – should pay for costly tolling systems. In contrast, scenarios allowing unlimited profit maximization raise substantial profi...
AbstractThis study formulates three fundamental extensions of the standard optimal road use analysis: (1) considering fuel and emissions as variable costs, (2) maximizing the social welfare inside ...
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Abstract This study provides the overall social welfare implications of key road-capacity expansion options considering free capacity, high occupancy vehicle – HOV, high occupancy toll – HOT, and toll lanes. The broad welfare impacts are... more
Abstract This study provides the overall social welfare implications of key road-capacity expansion options considering free capacity, high occupancy vehicle – HOV, high occupancy toll – HOT, and toll lanes. The broad welfare impacts are estimated in terms of transport users, residents, the regional economy, and private-sector’s welfare. The study uses Dallas County and Tarrant County, Texas, as a case-study region. The study result shows that the HOT option outperforms all other options. It results in an overall increase in social welfare in net present value of $6.7 billion. Apart from that, estimation results do not clearly suggest a preferred option, but instead, depend on the criterion used. The best option in each criterion is: “Do nothing” for investment costs, “HOT” for regional economic impact, “All-tolled” for corridor travel time, “HOT” for network-wide travel time, “Free capacity” for users’ travel costs, “All-tolled” for energy and environmental costs, and “All-tolled” for revenue. The proposed social welfare analysis integrates these conflicting criteria by offering a unified index, and provides the best road-investment option for society.
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Providing travel-related fuel and environmental information to transport users is becoming increasingly relevant. However, the impact of providing such information on users’ travel behavior is yet to be determined. This research examined... more
Providing travel-related fuel and environmental information to transport users is becoming increasingly relevant. However, the impact of providing such information on users’ travel behavior is yet to be determined. This research examined the perceptions and preferences related to the fuel consumption costs, greenhouse gas (GHG) social costs, and health-related air pollution costs, and the influence such information could have on travel behavior. Examining the case of Montreal transport users, the authors conducted a survey in which the respondents were asked general and stated preference questions. The respondents were found to be unaware of the energy and environmental footprints of their travel. Approximately 85% of the respondents were not able to estimate GHG social costs and health-related air pollution costs across different modes. The respondents generally overestimated these costs and they interestingly reported higher environmental costs for public transport (metro) compare...
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This study provides a literature review of the simulation-based connected and automated intelligent-vehicle studies. Media and car-manufacturing companies predict that connected and automated vehicles (CAVs) would be available in the near... more
This study provides a literature review of the simulation-based connected and automated intelligent-vehicle studies. Media and car-manufacturing companies predict that connected and automated vehicles (CAVs) would be available in the near future. However, society and transportation systems might not be completely ready for their implementation in various aspects, e.g., public acceptance, technology, infrastructure, and/or policy. Since the empirical field data for CAVs are not available at present, many researchers develop micro or macro simulation models to evaluate the CAV impacts. This study classifies the most commonly used intelligent-vehicle types into four categories (i.e., adaptive cruise control, ACC; cooperative adaptive cruise control, CACC; automated vehicle, AV; CAV) and summarizes the intelligent-vehicle car-following models (i.e., Intelligent Driver Model, IDM; MICroscopic Model for Simulation of Intelligent Cruise Control, MIXIC). The review results offer new insight...
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Abstract We review major revenue risk-sharing approaches developed world-wide that are designed to mitigate concessionaire risk and thus encourage private participation in public-private partnership (P3) arrangements. We examine variable... more
Abstract We review major revenue risk-sharing approaches developed world-wide that are designed to mitigate concessionaire risk and thus encourage private participation in public-private partnership (P3) arrangements. We examine variable availability payments, minimum revenue guarantees (MRG), variable-term contracts, financial re-balancing, and dynamic revenue insurance approaches. The preferred choice among these approaches depends on the level of demand risk, the risk-taking preferences of both partners, and the nature of the project, among others. For instance, highly-flexible tolling regulations help mitigate revenue risk since the private partner can adjust tolls to cope with varying demand, and as a result, riskier approaches such as Least Present Value Revenue (LPVR) or even full revenue risk may become acceptable to the private sector. In addition to these case-specific factors, we recommend public agencies follow several general guidelines, including: (i) for MRGs, a collar option (high and low thresholds) performs best since it can preserve the private incentive to increase revenue and performance; (ii) institutional stability can play an important role in the level of guarantees, e.g., Chile could employ P3s with fewer guarantees as a result of stable and well-established P3 programs/legislations; and (iii) P3 partners should also explore alternative options to mitigate revenue risks such as providing flexible pricing, controlling non-compete clauses, and allowing new technology adaption.
ABSTRACT There has been increasing scholarly interest in public-private partnerships (PPPs) and innovative financing approaches to deliver transportation infrastructure. Researchers have examined such issues as the effect of PPPs on... more
ABSTRACT There has been increasing scholarly interest in public-private partnerships (PPPs) and innovative financing approaches to deliver transportation infrastructure. Researchers have examined such issues as the effect of PPPs on delivery times, on cost efficiency, and on the cost of capital. There has, however, been relatively little empirical study of the effects of private participation in road management on road safety. We contribute to the literature on PPPs by conducting an empirical study of the effects of alternative types of toll road management, including private, on road safety in Mexico. We utilize an extensive data set examining accidents at the municipal level from 1997 to 2009, resulting in 10,772 observations. We consider several safety measures, including the overall number of accidents, the number of fatal accidents, the number of car collisions, and the number of fixed-object collisions. We control for a number of independent variables in addition to the type of road manager. We find little evidence that private management of Mexican toll roads has a statistically discernible effect on road safety, either positive or negative. Our findings may help to allay fears that private participants will sacrifice road safety in the interest of greater profits.
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ABSTRACT People's poor perception of the amount they spend on fuel is considered to be an important reason for the low price elasticity of gasoline demand. Users' travel demand can be changed by making them more aware of... more
ABSTRACT People's poor perception of the amount they spend on fuel is considered to be an important reason for the low price elasticity of gasoline demand. Users' travel demand can be changed by making them more aware of the fuel costs of different routes. As a result of becoming informed about their petrol consumption cost prior to entering traffic congestion, users may take an alternative route, change their travel schedule, or decide not to travel at all. Without considering the change in the price elasticity of gasoline demand, this study estimates the effects of providing gasoline consumption information (GCI) on people's route choice behaviour, the influence of fuel price on the effectiveness of the GCI in changing users' route choice behaviour, and the comparative effectiveness of providing GCI and using congestion pricing schemes. The results from a small network show that providing this information can improve people's behaviour in terms of route choice and that the results are comparable to those of congestion pricing schemes in terms of total travel time saved, especially for high travel demand and moderate fuel price conditions. The social benefits of providing the GCI are significantly and nonlinearly affected by the pre-policy proportion of uninformed users.
Research Interests: Civil Engineering, Transportation Engineering, Economics, Environmental Economics, Public Administration, and 15 morePublishing, Sustainable Transportation, Transportation Economics, Road Transport, Congestion Control, Consumer Behavior, Intelligent Transportation Systems, Transportation, Behavioral Economics, Academic research, Commissioning, Advanced Traffic Information Systems, Fuel Consumption, Gasoline, and Public Policy
Sustainable transport commonly considers either the interaction between built and natural environments or the interface between transportation and interdependent critical infrastructure. Although considering each of these key dimensions... more
Sustainable transport commonly considers either the interaction between built and natural environments or the interface between transportation and interdependent critical infrastructure. Although considering each of these key dimensions is a crucial task for achieving sustainable transport, the dimensions are infrequently considered together. When an integrated network design framework is proposed, two important issues are taken into account: (a) the aftermath of potential severe weather episodes on metropolitan-area infrastructure and (b) the existing interdependencies across transportation and fuel supply chain networks. Then the response of infrastructure in the face of flooding hazards is investigated. Framed within a multistage linear stochastic program, the proposed model seeks to find fueling station deployment that provides the transportation network with optimum random functionality when the network is stressed or under attack. A set of numerical experiments illustrates how changes to enhancement strategies at different stages of government affect the optimal investments in resilient design.
Research Interests:
A B S T R A C T Two major extreme-weather events occurred in New York State between 2011 and 2012. Each with the odds of a 100-year occurrence suggesting that such extreme events are the region's " new normal. "... more
A B S T R A C T Two major extreme-weather events occurred in New York State between 2011 and 2012. Each with the odds of a 100-year occurrence suggesting that such extreme events are the region's " new normal. " City and state policy-makers, in response, are studying how to develop a network of robust, resilient critical infrastructure facilities. These studies, however, typically fail to address interdependencies among critical infrastructures and lack a quantitative tool to investigate the maximum resilience possessed by a given infrastructure facility in the face of climate-change-induced hazards. We propose a multi-stage stochastic mathematical program to maximize network resilience given: i) random arrival of extreme events; ii) the network's inherent capacity to withstand and cope with the aftermath of exogenous shocks; iii) pre-, during-, and post-event strategies available to enhance system operability; and iv) budgeting and technological restrictions facing policy-makers. Our approach allows both qualitative and quantitative paradigms to interact. Our model thus clarifies how to allocate resources proactively and how the network's absorptive, adaptive, and restorative capacities can be coordinated to enhance overall system resilience. Our findings suggest that an integrated planning approach combined with smart allocation of resources across a network's main elements creates a greater degree of resilience while utilizing less costly resilience-enhancing strategies.
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ABSTRACT This report provides a detailed explanation of the “Randomizer” program. The “Randomizer” program calculates the benefits of Electric Program Investment Charge (EPIC) research projects by estimating the effects of the projects on... more
ABSTRACT This report provides a detailed explanation of the “Randomizer” program. The “Randomizer” program calculates the benefits of Electric Program Investment Charge (EPIC) research projects by estimating the effects of the projects on some of the parameters incorporated in the RPS Calculator. The “Randomizer” program is written in the VB environment inside an Excel spreadsheet. The program determines the random effects of EPIC projects on the model’s parameters. Values for the effects on the parameters are drawn repeatedly from one of the few statistical or empirical distributions. Once a set of values are drawn for all the involved parameters, the modified RPS Calculator is run. The main modification is related to the demand responsiveness to electricity prices. Finally, changes in electricity prices, carbon emissions, and renewable portfolios from the base case (without EPIC projects) are reported as the outputs of the program.
This paper offers a broad overview of road pricing from a social welfare perspective. I first examine two common objectives of road pricing: congestion management and profit making. My goal is to provide a guideline explaining how to... more
This paper offers a broad overview of road pricing from a social welfare perspective. I first examine two common objectives of road pricing: congestion management and profit making. My goal is to provide a guideline explaining how to promote a social-welfare-enhancing road pricing scheme. To this end, we should: (i) consider and improve public transportation systems by providing more environment-friendly transport options; (ii) include tolling profits in our welfare analysis (as opposed to what economists suggest) since residents are the real owners of roads not users, and since some users are from outside the region and so might not be excluded from analysis; and (iii) search for a holistic approach that takes into account system-wide impacts, disutility to users who change their travel behavior (i.e., switch to public transportation, shift their travel, or do not travel at all), and the impacts on land use, employment, and residents.
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Research Interests: Civil Engineering, Transportation Engineering, Economics, Transport Economics, Public Administration, and 18 moreSustainable Transportation, Asset Pricing, Transportation Studies, Public Transport, Transportation Economics, Transport Planning, Project Finance, Transport Modeling, Transportation, Urban And Regional Planning, Public Private Partnerships, Privatization, Transportation modelling, Transportation Network Analysis, Travel Demand Modeling, Tranport Planning, Private Investment In Public Equity (PIPE), and Public Policy
Research Interests:
Renewable portfolio standards (RPSs') require a certain fraction of the electricity generated for a given region be produced from renewable resources. California's RPS mandates that by 2020, 33% of the electricity sold in the state must... more
Renewable portfolio standards (RPSs') require a certain fraction of the electricity generated for a given region be produced from renewable resources. California's RPS mandates that by 2020, 33% of the electricity sold in the state must be generated from renewables. Such mandates have important implications for the electricity sector as well as for the whole society. In this paper, we estimate the costs and benefits of varying 2020 California RPS targets on electricity prices, greenhouse gas (GHG) emissions, criteria pollutant emissions, the electricity generation mix, the labor market, renewable investment decisions, and social welfare. We have extended the RPS Calculator model, developed by Energy and Environmental Economics (E3) Inc., to account for distributions of fuel and generation costs, to incorporate demand functions, and to estimate the effects of RPS targets on GHG emissions, criteria pollutant emissions, and employment. The results of our modeling provide the following policy insights: (1) the average 2020 electricity price increases as the RPS target rises, with values ranging between $0.152 and $0.175/kW h (2008 dollars) for the 20% RPS to 50% RPS, respectively; (2) the 33% and 50% RPS targets decrease the GHG emissions by about 17.6 and 35.8 million metric tons of carbon dioxide equivalent (MMTCO 2 e) relative to the 20% RPS; (3) the GHG emission reduction costs of the RPS options are high ($71–$94 per ton) relative to results from policy options other than RPS or prices that are common in the carbon markets; and (4) a lower target (e.g., a 27% RPS) provides higher social welfare than the 33% RPS (mandate) under low and moderate CO 2 social costs (lower than $35/ton); while a higher RPS target (e.g., 50%) is more beneficial when using high CO 2 social costs or rapid renewable technology diffusion. However, under all studied scenarios, the mandated 33% RPS for California would not provide the best cost/benefit values among the possible targets and would not maximize the net social benefit objective.
Research Interests: Management, Engineering, Environmental Science, Economics, Energy Economics, and 16 moreSocial Sciences, Climate Change, Renewable Energy, Wind Energy, Sustainable Development, Energy Policy, Geothermal, Modeling and Simulation, Public Health, Renewable energy resources, Environmental Sustainability, Energy efficiency, Electricity, California, Renewable Portfolio Standards, and Public Policy
I passed the October-2021 PE-Civil-Paper exam and decided to share my experience. In this book, you can find the closest tests to what was in the exam. The book includes three sections: (1) brief bullet points regarding the best... more
I passed the October-2021 PE-Civil-Paper exam and decided to share my experience. In this book, you can find the closest tests to what was in the exam. The book includes three sections: (1) brief bullet points regarding the best strategies to take the exam, (2) one practice exam (AM), and (3) the exam solution.
Research Interests:
I passed the October-2021 PE-Civil-Paper exam and decided to share my experience. In this book, you can find the closest tests to what was in the exam. The book includes three sections: (1) brief bullet points regarding the best... more
I passed the October-2021 PE-Civil-Paper exam and decided to share my experience. In this book, you can find the closest tests to what was in the exam. The book includes three sections: (1) brief bullet points regarding the best strategies to take the exam, (2) one practice exam (Transportation PM), and (3) the exam solution.