19 research outputs found

    Contribution of the Personal Rapid Transit (PRT) systems to the road safety: A scenario-based comparative evaluation

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    17th International Conference of Hong Kong Society for Transportation Studies: Transportation and Logistics Management, HKSTS 2012; Kowloon; Hong Kong; 15 December 2012 through 17 December 2012Though the number of "real ground" PRT projects are few, it can be possible to deduce some hypothetical safety conclusions. For the very optimist assumption that the control algorithms will only "allow" them to operate in non-collision mode on the network, the safety figures are re-evaluated for two urban settings: First (1) is the case where the urban design was fully recreated based on PRT system. The other (2) is the hypothetical PRT system would be embedded into the existing transportation system. The two cases of the safety measures and cost figures are compared to evaluate the opportunities and pitfalls by the application of a PRT system via the scenario analysis. By doing so, after description of the present situation, there comes the construction of possible alternative futures to compare with the present one. It can be deduced that, even if the safety figures of PRT system are hypothetical, PRT-based urban environments promise a lot in terms of safety levels (as far as 80 per cent) with, however, the expense of financial burden for the local government. Yet, for low-cost solution, PRT-embedded urban environments also provide promising results compared to "doing nothing" as far as 30 per cent reductions, in accidents in total and 44 per cent in deaths

    The method of policy capturing for the transportation disadvantaged: Simulation results

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    Ninth International Conference on Urban Transport and the Environment for the 21st Century, URBAN TRANSPORT IX; Crete; Greece; 10 March 2003 through 12 March 2003In the previous study called "A Modelling Approach for the Transportation Disadvantaged", which was an experimental one calibrated in a small town in Turkey, it was observed that an integrated TPM for the disadvantaged category was probable, and the findings were observable at all stages of the sequential modelling, however, with slight differences compared to the Normal model's results. Following the previous one, this study shows the method of how "policy capturing" could be possible on the basis of these differences, which aims to help improve the adverse conditions of the disadvantaged. The method is sort of category analysis based on the cluster analysis results, since it is clearly verified that the "disadvantage indices" identified as the single-disadvantage groups match with the values of cluster centres. Using TRANUS software, three simulations are run for three dimensions of disadvantage: socio-economic (categorical), spatial and the positional. The simulation results, evaluated from different criteria, showed that socio-economic dimension was the most fruitful area for policy capturing

    Impacts of transportation projects on urban trends in İzmir

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    The effects of major transportation projects on urban trends in Izmir were analyzed using the Delphi method. Once convergence was maintained in expert opinions, the Delphi results were re-evaluated according to the suggested method of total evaluation for obtaining much concise and general results. Accordingly, Absolute Total Impacts (ATI), Net Total Impacts (NTI) and the impact levels in broader terms were defined. The most effective projects were found to be: Integrated Rail Transportation System, Enhancement of Existing İzmir Port. The most impacted trends were: Development in Tourism Sector, Economic Development, Air Pollution and the Ratio of Private Car Ownership

    Making accident data compatible with ITS-based traffic management: Turkish case

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    One of the most important reasons of the high rate of accidents would largely lend itself to ineffective data collection and evaluation process since the necessary information cannot be obtained effectively from the traffic accidents reports (TAR). The discord and dealing with non-relevant data may appear at four levels: (1) Country and Cultural, (2) Institutional and organizational, (3) Data collection, (4) Data analysis and Evaluation. The case findings are consistent with this knowledge put forward in the literature; there is a transparency problem in coordination between the institutions as well as the inefficient TAR data, which is open to manipulation; the problem of under-reporting and inappropriate data storage prevails before the false statistical evaluation methods. The old-fashioned data management structure causes incompatibility with the novel technologies, avoiding timely interventions in reducing accidents and alleviating the fatalities. Transmission of the data to the interest agencies for evaluation and effective operation of the ITS-based systems should be considered. The problem areas were explored through diagnoses at institutional, data collection, and evaluation steps and the solutions were determined accordingly for the case city of Izmir.The Turkish Scientific and Technical Research Institut

    The effects of transportation projects on urban trends in İzmir

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    İzmir’deki önemli ulaştırma projelerinin kentsel eğilimlere olan etkileri Delphi yöntemi sonuçları temel alınarak analiz edilmiştir. Delphi yöntemine göre yakınsama sağlanmış etkiler, sonrasında daha anlamlı ve özet sonuçlar elde etmek amacıyla toplamdaki etkiler yöntemiyle yeniden değerlendirilmiştir. Yönteme göre, mutlak toplam etkilere (MED), net toplam etkilere (NED) ve en genel anlamda etki yeterlik düzeylerine bakılarak genel sonuçlara ulaşılmıştır. En etkili (olumlu/olumsuz yönde) projeler, bütünleştirilmiş raylı toplu taşıma sistemi, mevcut İzmir limanının geliştirilmesi; en fazla etkilenen sosyoekonomik eğilimler ise turizm sektöründeki gelişim, ekonomik gelişme, hava kirliliği ve özel araç kullanım oranı olarak çıkmıştır.The effects of major transportation projects on the urban trends in İzmir were analyzed using the Delphi method. Once the convergence was maintained in the expert opinions, the Delphi results were re-evaluated according to suggested method of total evaluation for obtaining much concise and general results. Accordingly, Absolute Total Impacts (MED), Net Total Impacts (NED) and the impact levels in broader terms were defined. The most effective projects were found to be: Integrated Rail Transportation System, Enhancement of Existing İzmir’s Port. The most impacted trends were: Development in Tourism Sector, Economic Development, Air Pollution and the Rate of Private Car Ownership

    A specaial transportation modelling approach for the disadvantaged groups in urban traffic

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    Thesis (Doctoral)--Izmir Institute of Technology, City and Regional Planning, Izmir, 2000Includes bibliographical references (leaves: 294-301)Text in English; Abstract: Turkish and Englishxx, 400 leavesIt has been known that conventional transportation models and studies have been inadequate to solve the acute transportation problems in the urban areas to date that overwhelmingly those disadvantaged groups face. The major reason is probably that the qualitative and social parameters that could be the real factors in the explanation of the "disadvantagedness" have not been efficiently considered in the modelling because of the uncertainty, and non-normative nature of the models.This thesis study as a normative one offers basically two methodological approach that can be integrated to the normal models: First, the clear-cut defInition of so-called disadvantaged by the cluster analysis method, and second, application of the modelling procedures both for normal case and for the disadvantaged simulatenously by which the determination of policy packages (policy capturing) is probable on the basis ofthe differences between the two models. The improvement of disadvantaged means getting closer to the normality in transportation conditions. With this, it is meant that policy-making to improve the disadvantaged can even start from the modelling stages.As an innovative approach, vanous correlated variables are grouped into "Major" variables in the form of function formulations, which are thought best represent the social/qualitative parameters.In the model runs, latest version of TRANUS (6.0) was used to speed up the modelling process (especially the Trip Assignments). With TRANUS., categorical handling is possible. It is found that there appears a remarkable discrepancy between the two models at the level of Trip Generations (productions), and some different variables could be used in the model for disadvantaged.Finally, in the Correspondence Module (or, category analysis), as of the adopted equity principles, the association of those disadvantaged categories (as transportation categories) with the "disadvantagedness" levels is maintained. This matching process also provided a gauge with which the policies could be produced for the matching transportation (disadvantaged) categories. To see the effectiveness of the method, three simulations are run based on the three policy scenarios where any move towards betterment in the condition of disadvantaged is welcome.As the result of this study, though less than expected, an improvement was observed in the travel conditions of the disadvantaged. It is observed not surprisingly that policy formulations playing around the income related and vehicle ownership variables can be more successful in obtaining better results. More frequent trials with better scenario formulations as well would have ended with better results.Key Words: Transportation Planning, Equity, Transportation Disadvantaged, Cluster Analysis, Category (Correspondence) Analysis, Transportation Ethics, Modelling-, Fuzzy Sets Analysis, Sensitivity Analysis, Simulation-, Gini Index

    The function of boundary determination:A case study of primary schoools in Keçiören.

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    A specaial transportation modelling approach for the disadvantaged groups in urban traffic

    No full text
    Thesis (Doctoral)--Izmir Institute of Technology, City and Regional Planning, Izmir, 2000Includes bibliographical references (leaves: 294-301)Text in English; Abstract: Turkish and Englishxx, 400 leavesIt has been known that conventional transportation models and studies have been inadequate to solve the acute transportation problems in the urban areas to date that overwhelmingly those disadvantaged groups face. The major reason is probably that the qualitative and social parameters that could be the real factors in the explanation of the "disadvantagedness" have not been efficiently considered in the modelling because of the uncertainty, and non-normative nature of the models.This thesis study as a normative one offers basically two methodological approach that can be integrated to the normal models: First, the clear-cut defInition of so-called disadvantaged by the cluster analysis method, and second, application of the modelling procedures both for normal case and for the disadvantaged simulatenously by which the determination of policy packages (policy capturing) is probable on the basis ofthe differences between the two models. The improvement of disadvantaged means getting closer to the normality in transportation conditions. With this, it is meant that policy-making to improve the disadvantaged can even start from the modelling stages.As an innovative approach, vanous correlated variables are grouped into "Major" variables in the form of function formulations, which are thought best represent the social/qualitative parameters.In the model runs, latest version of TRANUS (6.0) was used to speed up the modelling process (especially the Trip Assignments). With TRANUS., categorical handling is possible. It is found that there appears a remarkable discrepancy between the two models at the level of Trip Generations (productions), and some different variables could be used in the model for disadvantaged.Finally, in the Correspondence Module (or, category analysis), as of the adopted equity principles, the association of those disadvantaged categories (as transportation categories) with the "disadvantagedness" levels is maintained. This matching process also provided a gauge with which the policies could be produced for the matching transportation (disadvantaged) categories. To see the effectiveness of the method, three simulations are run based on the three policy scenarios where any move towards betterment in the condition of disadvantaged is welcome.As the result of this study, though less than expected, an improvement was observed in the travel conditions of the disadvantaged. It is observed not surprisingly that policy formulations playing around the income related and vehicle ownership variables can be more successful in obtaining better results. More frequent trials with better scenario formulations as well would have ended with better results.Key Words: Transportation Planning, Equity, Transportation Disadvantaged, Cluster Analysis, Category (Correspondence) Analysis, Transportation Ethics, Modelling-, Fuzzy Sets Analysis, Sensitivity Analysis, Simulation-, Gini Index

    Can Tube Tunnel Crossings Relieve Urban Congestion Problems? Izmir Tube Tunnel Project Proposal Under Scrutiny

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    Building underwater tube tunnel crossings to ease the urban congestion problems has become a popular approach for many cities across the globe. London, New York, Istanbul, Hamburg, Sydney and Brisbane are among these cities. However, the effectiveness and externalities of these expensive mega urban infrastructures have also been questioned widely among urban, transport and environmental planning scholars. Given the international popularity of the topic, this study places a new tube tunnel crossings project from Izmir, Turkey under the microscope. In this heuristic simulation study, policy-on scenarios were tested to determine possible impacts of the underwater tube tunnel-crossing project. The traffic impacts are discussed using simulations assigning the initial origin–destination data. The results of the study revealed that, given the two locations, outer and inner locations over the dagger-shape bay, the capacity increments on the bridge links and the links around the periphery highway did not bring any effective solutions beyond some minor improvements. The findings disclosed that the ineffectiveness of the tube tunnel crossing might be due to the excessive congestion happening all over the downtown area, which clogs the passageways to the bridge. The paper highlights the limitations of the tube tunnel-crossing project, emphasises the need for comprehensive investigations before committing to the project and advocates the emphasis to be actually given for sustainable mobility

    The method of policy capturing for the transportation disadvantaged: Simulation results

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    Ninth International Conference on Urban Transport and the Environment for the 21st Century, URBAN TRANSPORT IX; Crete; Greece; 10 March 2003 through 12 March 2003In the previous study called "A Modelling Approach for the Transportation Disadvantaged", which was an experimental one calibrated in a small town in Turkey, it was observed that an integrated TPM for the disadvantaged category was probable, and the findings were observable at all stages of the sequential modelling, however, with slight differences compared to the Normal model's results. Following the previous one, this study shows the method of how "policy capturing" could be possible on the basis of these differences, which aims to help improve the adverse conditions of the disadvantaged. The method is sort of category analysis based on the cluster analysis results, since it is clearly verified that the "disadvantage indices" identified as the single-disadvantage groups match with the values of cluster centres. Using TRANUS software, three simulations are run for three dimensions of disadvantage: socio-economic (categorical), spatial and the positional. The simulation results, evaluated from different criteria, showed that socio-economic dimension was the most fruitful area for policy capturing
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