Single Stage Integer Programming Model for Long Term Transit Fleet Resource Allocation
Authors: Sabyasachee Mishra, Tom V. Mathew, and Snehamay Khasnabis (2010)
Report
Synopsis: The authors present a procedure for resource allocation among transit agencies for transit fleet management, specifically focusing on the purchase of new buses and rebuilding of existing buses. The model is formulated as a non-linear optimization problem of maximizing the total weighted average remaining life of the fleet subject to budgetary, policy and other constraints. The problem is solved using Integer Programming (IP) and its application is demonstrated through a case study utilizing actual transit fleet data from the Michigan Department of Transportation.
Authors: Sabyasachee Mishra and Snehamay Khasnabis (2012)
Report
Synopsis: The authors present a procedure for allocating resources for implementing safety improvement alternatives at urban intersections over a multi-year planning horizon. The procedure, based upon optimization techniques, attempts to maximize benefits-measured in dollars saved by reducing crashes of different severity categories, subject to budgetary and other constraints. It is presented in two parts (1) a Base case including the objective function and a set of mandatory constraints, and (2) additional policy constraints / special features that can be separately incorporated to the Base case.
Authors: Snehamay Khasnabis, Sunder Lall Dhingra, Sabyasachee Mishra, and Chirag Safi (2010)
Report
Synopsis: In this paper, the authors examine different investment mechanisms for transportation infrastructure projects involving the private enterprise in developing countries. Roles identified vary from those of a financier to an operator for successful public-private ventures. A case study involving such a joint venture in India, the Mumbai Pune Expressway/National Highway 4 (MPEW/NH4) is presented, and fiscal implications of the program, both from the perspective of the public and the private enterprise are examined. The study concludes that if properly planned, joint ventures can be mutually beneficial. A joint public-private program may enable the public sector to use the resources saved for other public projects. It also provides the private agency an opportunity to invest monies in a profitable enterprise that yields social benefits, (e.g. improving mobility, promoting economic development, etc.). Careful analysis must be conducted before the project is undertaken to assess the financial and economic implications of the project from each participant’s viewpoint, with due regard to risks and uncertainties associated with such long term investments.
Authors: Snehamay Khasnabis, Sabyasachee Mishra, and Chirag Safi (2012)
Report
Synopsis: The purpose of evaluating mutually exclusive alternatives is to select the one with the highest benefits for implementation. A number of analytic techniques are available for such evaluation purposes. Four such techniques: Cost Effectiveness (C/E), Benefit Cost Ratio (B/C), Internal Rate of Return (IRR), and Pay-off Period (PP) are discussed in this paper, including their theoretical foundation and data requirements, Also discussed are the measures of effectiveness (MOE) associated with each of these techniques, and how these are to be interpreted.
Authors: Sabyasachee Mishra, Snehamay Khasnabis, and Sunder Lall Dhingra (2012)
Report
Synopsis: Traditional economic analysis techniques used in the assessment of Public Private Partnership (PPP) projects are based upon the assumption that future cash flows are fully deterministic in nature and are not designed to account for risks involved in the assessment of future returns. In reality, many of these infrastructure projects are associated with significant risks stemming from the lack of knowledge about future cost and benefit streams. The fundamental premise of the PPP concept is to efficiently allocate risks between the public and the private partner. The return based on deterministic analysis may not depict a true picture of future economic outcomes of a PPP project for the multiple agencies involved. This deficiency underscores the importance of risk-based economic analysis for such projects. In this paper, the authors present the concept of Value-at-Risk (VaR) as a measure of effectiveness (MOE) to assess the risk share for the public and private entity in a PPP project. Bootstrap simulation is used to generate the risk profile savings in vehicle operating cost, and in travel time resulting from demand-responsive traffic. The VaR for Internal Rate of Return (IRR) is determined for public and private entity. The methodology is applied to a case study involving such a joint venture in India, the Mumbai Pune
Authors: Tom V. Mathewa, Snehamay Khasnabisb, and Sabyasachee Mishra (2010)
Report
Synopsis: Most transit agencies require government support for the replacement of their aging fleet. A procedure for equitable resource allocation among competing transit agencies for the purpose of transit fleet management is presented in this study. The proposed procedure is a 3-dimensional model that includes the choice of a fleet improvement program, agencies that may receive them, and the timing of investments. Earlier efforts to solve this problem involved the application of one or 2-dimensional models for each year of the planning period. These may have resulted in suboptimal solution as the models are blind to the impact of the fleet management program of the subsequent years. Therefore, a new model to address a long-term planning horizon is proposed. The model is formulated as a non-linear optimization problem of maximizing the total weighted average remaining life of the fleet subjected to improvement program and budgetary constraints. Two variants of the problem, one with an annual budget constraint and the other with a single budget constraint for the entire planning period, are formulated. Two independent approaches, namely, branch and bound algorithm and genetic algorithm are used to obtain the solution. An example problem is solved and results are discussed in details. Finally, the model is applied to a large scale real-world problem and a detailed analysis of the results is presented.
Authors: Sabyasachee Mishra, Tom V. Mathew, and Snehamay Khasnabis (2010)
Report
Synopsis: The authors present a procedure for resource allocation among transit agencies for transit fleet management, specifically focusing on the purchase of new buses and rebuilding of existing buses. The model is formulated as a non-linear optimization problem of maximizing the total weighted average remaining life of the fleet subject to budgetary, policy and other constraints. The problem is solved using Integer Programming (IP) and its application is demonstrated through a case study utilizing actual transit fleet data from the Michigan Department of Transportation.
An Optimization Model for Allocating Resources for Highway Safety Improvement at Urban Intersections
Authors: Sabyasachee Mishra and Snehamay Khasnabis (2012)
Report
Synopsis: The authors present a procedure for allocating resources for implementing safety improvement alternatives at urban intersections over a multi-year planning horizon. The procedure, based upon optimization techniques, attempts to maximize benefits-measured in dollars saved by reducing crashes of different severity categories, subject to budgetary and other constraints. It is presented in two parts (1) a Base case including the objective function and a set of mandatory constraints, and (2) additional policy constraints / special features that can be separately incorporated to the Base case.
Mechanisms for Transportation Infrastructure Investment in Developing Countries
Authors: Snehamay Khasnabis, Sunder Lall Dhingra, Sabyasachee Mishra, and Chirag Safi (2010)
Report
Synopsis: In this paper, the authors examine different investment mechanisms for transportation infrastructure projects involving the private enterprise in developing countries. Roles identified vary from those of a financier to an operator for successful public-private ventures. A case study involving such a joint venture in India, the Mumbai Pune Expressway/National Highway 4 (MPEW/NH4) is presented, and fiscal implications of the program, both from the perspective of the public and the private enterprise are examined. The study concludes that if properly planned, joint ventures can be mutually beneficial. A joint public-private program may enable the public sector to use the resources saved for other public projects. It also provides the private agency an opportunity to invest monies in a profitable enterprise that yields social benefits, (e.g. improving mobility, promoting economic development, etc.). Careful analysis must be conducted before the project is undertaken to assess the financial and economic implications of the project from each participant’s viewpoint, with due regard to risks and uncertainties associated with such long term investments.
An Evaluation Procedure for Mutually Exclusive Highway Safety Alternatives under Different Program Missions
Authors: Snehamay Khasnabis, Sabyasachee Mishra, and Chirag Safi (2012)
Report
Synopsis: The purpose of evaluating mutually exclusive alternatives is to select the one with the highest benefits for implementation. A number of analytic techniques are available for such evaluation purposes. Four such techniques: Cost Effectiveness (C/E), Benefit Cost Ratio (B/C), Internal Rate of Return (IRR), and Pay-off Period (PP) are discussed in this paper, including their theoretical foundation and data requirements, Also discussed are the measures of effectiveness (MOE) associated with each of these techniques, and how these are to be interpreted.
A Simulation Approach for Modeling Risk in Transportation Infrastructure Investment Decision Making
Authors: Sabyasachee Mishra, Snehamay Khasnabis, and Sunder Lall Dhingra (2012)
Report
Synopsis: Traditional economic analysis techniques used in the assessment of Public Private Partnership (PPP) projects are based upon the assumption that future cash flows are fully deterministic in nature and are not designed to account for risks involved in the assessment of future returns. In reality, many of these infrastructure projects are associated with significant risks stemming from the lack of knowledge about future cost and benefit streams. The fundamental premise of the PPP concept is to efficiently allocate risks between the public and the private partner. The return based on deterministic analysis may not depict a true picture of future economic outcomes of a PPP project for the multiple agencies involved. This deficiency underscores the importance of risk-based economic analysis for such projects. In this paper, the authors present the concept of Value-at-Risk (VaR) as a measure of effectiveness (MOE) to assess the risk share for the public and private entity in a PPP project. Bootstrap simulation is used to generate the risk profile savings in vehicle operating cost, and in travel time resulting from demand-responsive traffic. The VaR for Internal Rate of Return (IRR) is determined for public and private entity. The methodology is applied to a case study involving such a joint venture in India, the Mumbai Pune
Optimal Resource Allocation Among Transit Agencies for Fleet Management
Authors: Tom V. Mathewa, Snehamay Khasnabisb, and Sabyasachee Mishra (2010)
Report
Synopsis: Most transit agencies require government support for the replacement of their aging fleet. A procedure for equitable resource allocation among competing transit agencies for the purpose of transit fleet management is presented in this study. The proposed procedure is a 3-dimensional model that includes the choice of a fleet improvement program, agencies that may receive them, and the timing of investments. Earlier efforts to solve this problem involved the application of one or 2-dimensional models for each year of the planning period. These may have resulted in suboptimal solution as the models are blind to the impact of the fleet management program of the subsequent years. Therefore, a new model to address a long-term planning horizon is proposed. The model is formulated as a non-linear optimization problem of maximizing the total weighted average remaining life of the fleet subjected to improvement program and budgetary constraints. Two variants of the problem, one with an annual budget constraint and the other with a single budget constraint for the entire planning period, are formulated. Two independent approaches, namely, branch and bound algorithm and genetic algorithm are used to obtain the solution. An example problem is solved and results are discussed in details. Finally, the model is applied to a large scale real-world problem and a detailed analysis of the results is presented.