The Experts below are selected from a list of 270 Experts worldwide ranked by ideXlab platform
Sakti Pramanik - One of the best experts on this subject based on the ideXlab platform.
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an efficient path Computation model for hierarchically structured topographical road maps
IEEE Transactions on Knowledge and Data Engineering, 2002Co-Authors: Sungwon Jung, Sakti PramanikAbstract:In this paper, we have developed a HiTi (Hierarchical MulTi) graph model for structuring large topographical road maps to speed up the minimum cost Route Computation. The HiTi graph model provides a novel approach to abstracting and structuring a topographical road map in a hierarchical fashion. We propose a new shortest path algorithm named SPAH, which utilizes HiTi graph model of a topographical road map for its Computation. We give the proof for the optimality of SPAH. Our performance analysis of SPAH on grid graphs showed that it significantly reduces the search space over existing methods. We also present an in-depth experimental analysis of HiTi graph method by comparing it with other similar works on grid graphs. Within the HiTi graph framework, we also propose a parallel shortest path algorithm named ISPAH. Experimental results show that inter query shortest path problem provides more opportunity for scalable parallelism than the intra query shortest path problem.
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an efficient path Computation model for hierarchically structured topographical road maps
IEEE Transactions on Knowledge and Data Engineering, 2002Co-Authors: Sungwon Jung, Sakti PramanikAbstract:In this paper, we have developed a HiTi (Hierarchical MulTi) graph model for structuring large topographical road maps to speed up the minimum cost Route Computation. The HiTi graph model provides a novel approach to abstracting and structuring a topographical road map in a hierarchical fashion. We propose a new shortest path algorithm named SPAH, which utilizes HiTi graph model of a topographical road map for its Computation. We give the proof for the optimality of SPAH. Our performance analysis of SPAH on grid graphs showed that it significantly reduces the search space over existing methods. We also present an in-depth experimental analysis of HiTi graph method by comparing it with other similar works on grid graphs. Within the HiTi graph framework, we also propose a parallel shortest path algorithm named ISPAH. Experimental results show that inter query shortest path problem provides more opportunity for scalable parallelism than the intra query shortest path problem.
Lilian S.c. Pun-cheng - One of the best experts on this subject based on the ideXlab platform.
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Optimal Route Computation for circular public transport Routes with differential fare structure
Travel Behaviour and Society, 2016Co-Authors: Lilian S.c. Pun-cheng, Albert W.f. ChanAbstract:In many public transport information systems, Route searching for pre-trip journey planning is an essential and important function. While different types of Route query and path finding algorithms have been proposed to solve the problem of optimum Route or path searching, there remains no single answer to the best solution for all public transportation networks in the world. As a result, customization of the optimum Route Computation is needed. In this paper, a structural analysis of public transport Routes in terms of fare and operation patterns has been conducted. An enhanced Route Computation algorithm has been proposed in order to provide more reasonable and logical results for different structures. The development and implementation of the programming logic, together with the validation of the enhanced algorithm are also presented. It is found that the traditional approach of selecting closest stops to origin, destination or interchange stops may not satisfy all patterns, especially for cities with a very dense network of public transport stops and for circular Routes. To cater for a lot of these special cases, the new approach of stop selection adopts a comparison of the stop sequence within a Route with a threshold of commuting behaviour. Real cases from a governmental public transportation enquiry system in Hong Kong are extracted for implementation and evaluation; results from which have been proved satisfactory to both system planners and users.
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An Interactive Web-Based Public Transport Enquiry System With Real-Time Optimal Route Computation
IEEE Transactions on Intelligent Transportation Systems, 2012Co-Authors: Lilian S.c. Pun-chengAbstract:A comprehensive and presentable public transport information system is deemed invaluable for local residents and tourists all over the world. This is particularly necessary in view of the complex city structure and transportation system in Hong Kong. There are more than ten public transportation modes available, all with different operation schedules, fare structures, and routing characteristics. To assist commuters in making better use of public transport, the system needs to be not only user friendly and informative but intelligent enough to provide optimal Route choices in terms of users' travelling behavior or preference as well. The web-map public transport enquiry system, as described in this paper, gives a good example of providing bilingual (English and Chinese) information on all public transports run in Hong Kong in the form of interactive maps and texts, as well as real-time derivation of optimal travelling Routes for users in terms of multiple criteria, i.e., preferred mode, least changes, shortest travelling time, or lowest fare.
Sungwon Jung - One of the best experts on this subject based on the ideXlab platform.
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an efficient path Computation model for hierarchically structured topographical road maps
IEEE Transactions on Knowledge and Data Engineering, 2002Co-Authors: Sungwon Jung, Sakti PramanikAbstract:In this paper, we have developed a HiTi (Hierarchical MulTi) graph model for structuring large topographical road maps to speed up the minimum cost Route Computation. The HiTi graph model provides a novel approach to abstracting and structuring a topographical road map in a hierarchical fashion. We propose a new shortest path algorithm named SPAH, which utilizes HiTi graph model of a topographical road map for its Computation. We give the proof for the optimality of SPAH. Our performance analysis of SPAH on grid graphs showed that it significantly reduces the search space over existing methods. We also present an in-depth experimental analysis of HiTi graph method by comparing it with other similar works on grid graphs. Within the HiTi graph framework, we also propose a parallel shortest path algorithm named ISPAH. Experimental results show that inter query shortest path problem provides more opportunity for scalable parallelism than the intra query shortest path problem.
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an efficient path Computation model for hierarchically structured topographical road maps
IEEE Transactions on Knowledge and Data Engineering, 2002Co-Authors: Sungwon Jung, Sakti PramanikAbstract:In this paper, we have developed a HiTi (Hierarchical MulTi) graph model for structuring large topographical road maps to speed up the minimum cost Route Computation. The HiTi graph model provides a novel approach to abstracting and structuring a topographical road map in a hierarchical fashion. We propose a new shortest path algorithm named SPAH, which utilizes HiTi graph model of a topographical road map for its Computation. We give the proof for the optimality of SPAH. Our performance analysis of SPAH on grid graphs showed that it significantly reduces the search space over existing methods. We also present an in-depth experimental analysis of HiTi graph method by comparing it with other similar works on grid graphs. Within the HiTi graph framework, we also propose a parallel shortest path algorithm named ISPAH. Experimental results show that inter query shortest path problem provides more opportunity for scalable parallelism than the intra query shortest path problem.
S C Punchenglilian - One of the best experts on this subject based on the ideXlab platform.
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an interactive web based public transport enquiry system with real time optimal Route Computation
IEEE Transactions on Intelligent Transportation Systems, 2012Co-Authors: S C PunchenglilianAbstract:A comprehensive and presentable public transport information system is deemed invaluable for local residents and tourists all over the world. This is particularly necessary in view of the complex c...
Albert W.f. Chan - One of the best experts on this subject based on the ideXlab platform.
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Optimal Route Computation for circular public transport Routes with differential fare structure
Travel Behaviour and Society, 2016Co-Authors: Lilian S.c. Pun-cheng, Albert W.f. ChanAbstract:In many public transport information systems, Route searching for pre-trip journey planning is an essential and important function. While different types of Route query and path finding algorithms have been proposed to solve the problem of optimum Route or path searching, there remains no single answer to the best solution for all public transportation networks in the world. As a result, customization of the optimum Route Computation is needed. In this paper, a structural analysis of public transport Routes in terms of fare and operation patterns has been conducted. An enhanced Route Computation algorithm has been proposed in order to provide more reasonable and logical results for different structures. The development and implementation of the programming logic, together with the validation of the enhanced algorithm are also presented. It is found that the traditional approach of selecting closest stops to origin, destination or interchange stops may not satisfy all patterns, especially for cities with a very dense network of public transport stops and for circular Routes. To cater for a lot of these special cases, the new approach of stop selection adopts a comparison of the stop sequence within a Route with a threshold of commuting behaviour. Real cases from a governmental public transportation enquiry system in Hong Kong are extracted for implementation and evaluation; results from which have been proved satisfactory to both system planners and users.
