Using Intersection Conflict Index in Urban Traffic Risk Evaluation

AbstractThis paper presents part of the research on traffic risk estimation for Bucharest City area. The aim of our research is to develop complex models as tools of urban traffic risk assessment in planning phase. In this way, several urban planning alternatives could be analysed and evaluate before important transport infrastructure investment are made. The first part of the paper analyses the state of road accidents recorded in Bucharest. The second part of the paper demonstrates how the intersection conflict index can be used in traffic micro-simulation models to assess measures of traffic risk reducing

Including negative externalities during transport infrastructure construction in assessment of investment projects

The paper presents a method for optimizing the financing option for transport infrastructure project. The execution time for large project is substantial and the social costs generated during the construction phase are insufficient included in the assessment models. These are the main reasons for starting the research to extend the project evaluation methods with procedures that consider also social costs during the implementation of the project, besides the social costs after work completion. The proposed method aims to enhance the solution given by the current applied methods for investment assessment. Starting from the results of the present procedures of transport investment assessment, two approaches are presented. The first one assumes that the work starts at the reference year and different construction schemes can be applied. The optimal time of project implementation is determined considering the social costs during construction and after project implementation. In the second approach, the purpose is to determine the moments of the starting and the completion of the works for minimum of the losses caused by the social costs before and during the project implementation. The paper emphasizes that social cost during transport infrastructure work must be considered in investment timing. In this regard, supplementary procedures can be added to the current method used for ranking of the transport infrastructure investments. For an investment measure identified as opportune, the proposed method aim to minimize the total social cost. Document type: Articl

Traffic Risk Generated by Large Urban Commercial Centers

AbstractAs a consequence of development policies urban areas are substantially different in terms of road traffic risk. The shape, size and configuration of urban areas, the transport supply to meet people and goods mobility needs, as well as human behavior have huge influence on the road traffic volume and pattern and, hence, on the associated road crash risk. In this context, the paper reveals the effects of locating large shopping centers in the central areas of the city on the already over-congested road network. We use specific spatial analysis models in order to estimate vehicle and customers flows, attracted by one of the largest shopping malls in Bucharest. This approach gives theoretical and practical added value to the study: providing analysis tools to local decision makers for the ex-ante assessment of the consequences of locating large malls, in terms of traffic flow and associated crash risk

On the Evaluation of Urban Logistics Intermodal Terminal Projects

This paper is looking to incorporate uncertainty and risk in the financial assessment of an urban logistics investment project - a ""rail-road" intermodal terminal performing urban logistic distribution functions. A "cost benefit analysis" (CBA) is performed for four decision scenarios (with different destinations and technologies). The variables included in the CBA are treated as random variables with different distribution functions (uniform, binomial, normal). The net present value (NPV) used to rank the different decision scenarios is based on results from a Monte Carlo simulation. NPV obtained as a discrete variable has been used to evaluate risk (expressed with specific indicators) and for the comparison with a NPV of a similar project in operation. A comparison with CBA that expresses NPV deterministically and the "states of nature" with known probabilities is made. Under uncertainty conditions (the "states of nature" completely unknown) the preferences of the decision maker are analysed for a certain scenario depending on his/her attitude towards risk (cautious, optimistic, pessimistic). The CBA is complemented by a "cost-efficacy analysis" (CEA) which reflects the manner in which the non-financial, social consequences of the project can be used to rank the decision scenarios. In conclusion, the paper pleads for the professionalism required by CBA and CEA, when risk and uncertainty cannot be ignored, this being the case of most infrastructure investments with social implications difficult to estimate financially. Refereed/Peer-reviewe

About the high capacity public transport networks territory functions

transit system’s infrastructure (tramways, underground or light rails) plays a major role in satisfying people’s need for mobility – by size and the stability of their operation, and also by the independence of their quality performance compared to cars facing traffic congestion, because of their dedicated operation. The authors analyzed the potential transport capacity of the transit network infrastructures in order to define their territory functions, through urban people and poles to determine daily urban mobility preferences (for work, study, business purposes) and occasional mobility (for sports, tourism, culture, health caring purposes). In a structured space (Bucharest city), using a GIS map and TranCAD software, the authors defined the cover/serve index for the 72 study areas. (quasi-homogenous areas regarding their social-economic activities). The authors determined a hierarchy of those areas which help to establish directions to adapt transit infrastructure topology to the fast growing rate of the urban development. The territory functions characterization of the transit networks is used also to determine the hierarchy of the most highly attractive centroids (using an index that takes also into account both people density of the different areas and the distance to the popular centroids). The results of the study emphasize the disparities in urban territory served by the transit transport infrastructure; they can represent a useful tool in transit networks development strategies

Including negative externalities during transport infrastructure construction in assessment of investment projects

Abstract The paper presents a method for optimizing the financing option for transport infrastructure project. The execution time for large project is substantial and the social costs generated during the construction phase are insufficient included in the assessment models. These are the main reasons for starting the research to extend the project evaluation methods with procedures that consider also social costs during the implementation of the project, besides the social costs after work completion. The proposed method aims to enhance the solution given by the current applied methods for investment assessment. Starting from the results of the present procedures of transport investment assessment, two approaches are presented. The first one assumes that the work starts at the reference year and different construction schemes can be applied. The optimal time of project implementation is determined considering the social costs during construction and after project implementation. In the second approach, the purpose is to determine the moments of the starting and the completion of the works for minimum of the losses caused by the social costs before and during the project implementation. The paper emphasizes that social cost during transport infrastructure work must be considered in investment timing. In this regard, supplementary procedures can be added to the current method used for ranking of the transport infrastructure investments. For an investment measure identified as opportune, the proposed method aim to minimize the total social cost