Browsing by Author "Carlos Munoz, Juan"

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    A multi-unit tender award process: The case of Transantiago
    (ELSEVIER, 2009) Carlos Munoz, Juan; Molina, Diego
    The Transantiago public transit services were grouped into five trunk service units and 10 feeder units, and were awarded to private operators through a simultaneous tender. To avoid problems of ownership concentration, limits were placed on the maximum number of units per operator. This paper describes the issues involved in Such Simultaneous multi-unit tenders where various actors bid for different business units to be awarded in a single tender process. The general problem is formulated as a minimum cost network flow problem (MCNFP). Tie-breaking criteria are discussed and modeled. The problem is then solved for the Transantiago case. There follows a discussion of the utility of handling this tender using the tool developed here. (C) 2008 Elsevier B.V. All rights reserved.
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    Alleviating a subway bottleneck through a platform gate
    (2018) Carlos Munoz, Juan; Soza Parra, Jaime Antonio; Didier, Arturo; Silva, Constanza; CEDEUS (Chile)
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    An equivalent optimization formulation for the traffic assignment problem with asymmetric linear costs
    (TAYLOR & FRANCIS LTD, 2009) de Grange, Louis; Carlos Munoz, Juan
    In this paper, we present a general formulation for the deterministic traffic assignment problem, using an equivalent optimization problem applicable to the case of asymmetric linear cost functions. We present a resolution approach for this problem in such a way that in equilibrium Wardrop's first principle or Nash equilibrium is satisfied. We conclude that many deterministic traffic assignment problems with asymmetric linear costs can be formulated as an optimization problem whose objective is defined by a line integral, and whose constraints correspond to non-negativity and flows conservation. By adequately defining the integration path, it is feasible to resolve the problem, obtaining Wardrop's equilibrium. This approach can be applied in other economic contexts, including microeconomic theory and consumer surplus analysis.
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    Choosing the Right Express Services for Bus Corridor with Capacity Restrictions
    (SAGE PUBLICATIONS INC, 2010) Larrain, Homero; Giesen, Ricardo; Carlos Munoz, Juan
    In public transit systems with high demand levels, the use of express bus services that serve only a subset of stops along certain routes appears to be a promising alternative given the benefits that they offer to both users and operators. In practice, express services in systems such as Transmilenio (Bogota, Colombia), Transantiago (Santiago, Chile), and Metro Rapid (Los Angeles, California) have proved highly appealing. To determine what types of express services would be attractive on a bus corridor given the characteristics of its demand, four parameters are defined for identifying corridor demand profiles: the base load profile shape, the scale of demand, the demand imbalance between the outbound and inbound directions, and the average trip length. A series of indicators was also defined to measure the potential benefits of express services in the scenarios studied. The results of the experimental simulations show that a crucial parameter for determining the potential benefits of express services is the average trip length along the corridor. The incorporation of express services is particularly attractive in corridors with demand profiles that increase or decrease monotonically. In addition, the results suggest that in other cases, the complexity of the demand shape could allow for more complex express service patterns.
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    Cost-Effective Measures for Reducing Road Fatalities in the Short Term
    (TAYLOR & FRANCIS LTD, 2011) Ignacio Rizzi, Luis; Cumsille, Sebastian; Fresard, Francisco; Gazmuri, Pedro; Carlos Munoz, Juan
    When traffic safety statistics in less developed countries (even those where enormous progress has been made in the last years) are compared with those of more advanced countries, it is evident that there is still a great deal to be done. Using Chile as a case study, we propose a set of measures to significantly reduce fatalities in the short term. A simple methodology is proposed to guide the process of selecting the most promising measures, taking into account their cost-effectiveness. Eight such measures are identified and their potential benefits and costs of implementation are estimated for our case study. Special care is taken in choosing measures aimed at protecting vulnerable road users who represent around 50% of road fatalities in Chile. The plan we propose has the potential to reduce 460 fatalities per year (i.e. 21%), as a conservative estimate. A discussion on the transferability of these results to other developing nations is offered.
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    Design of limited-stop services for an urban bus corridor with capacity constraints
    (PERGAMON-ELSEVIER SCIENCE LTD, 2010) Leiva, Carola; Carlos Munoz, Juan; Giesen, Ricardo; Larrain, Homero
    In high-demand bus networks, limited-stop services promise benefits for both users and operators, and have proven their attractiveness in systems such as Transmilenio (Bogota, Colombia) and Transantiago (Santiago, Chile). The design of these services involves defining their itinerary, frequency and vehicle size, yet despite the importance of these factors for the network's efficiency, no published works appear to provide the tools for designing high-frequency unscheduled services on an urban bus corridor, minimizing social costs.
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    On evasion behaviour in public transport: Dissatisfaction or contagion?
    (2019) Allen, Jaime; Carlos Munoz, Juan; Ortuzar Salas, Juan De Dios; CEDEUS (Chile)
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    The Role of Accessibility to Public Transport and Quality of Walking Environment on Urban Equity: The Case of Santiago de Chile
    (2018) Tiznado-Aitken, Ignacio; Carlos Munoz, Juan; Hurtubia González, Ricardo
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    Transantiago: The Fall and Rise of a Radical Public Transport Intervention
    (2009) Carlos Munoz, Juan; Ortuzar Salas, Juan De Dios; Gschwender, Antonio