The Experts below are selected from a list of 141 Experts worldwide ranked by ideXlab platform

Bin Ran - One of the best experts on this subject based on the ideXlab platform.

  • BILEVEL FORMULATION FOR OPTIMAL TRAFFIC-Information DISSEMINATION
    Transportation Research Record, 2003
    Co-Authors: Fan Yang, Henry X. Liu, Xuegang Ban, Bin Ran
    Abstract:

    With the fast-growing telematics market and maturing traffic-Information services, telematics devices provide a feasible means with which to manage traffic more efficiently. The provision of traffic Information to travelers usually involves different parties that have distinctive objectives: travelers are concerned with benefits of travel-time savings at an affordable service charge, private Information service providers (ISPs) seek to provide marketable Information services from which they can derive a profit, and traffic management centers (TMCs) have the responsibility to maintain and improve system performance, especially to minimize the total system travel time. How transportation system managers can analyze the trade-offs among these objectives and adjust this new traffic-Information Flow Diagram to improve system performance remains an open question. The trade-offs needed among the conflicting multiple objectives of different parties are studied, and traffic system performance is analyzed. The complex traffic network is formulated as a bilevel program. The upper level can be formulated by using various objective functions, such as the objectives for ISP and TMC. The lower level is a multiclass dynamic traffic-assignment model, which determines dynamic traffic Flows in the network by considering the Information dissemination strategies provided by the upper-level model. Numerical results of a small network are provided to illustrate the behavior of this model, and they prove that when there is congestion in the dynamic transportation network, appropriate subscribed rates benefit both all travelers and system performance, while the ISPs' Information influences little without congestion in the transportation network.

  • Bi-Level Formulation for Optimal Traffic Information Dissemination
    2002
    Co-Authors: Fan Yang, Henry X. Liu, Xuegang Ban, Bin Ran
    Abstract:

    With the fast-growing telematics market and maturing traffic Information services, the pervasive use of telematics devices provides a feasible means of more efficiently managing traffic. Providing traffic Information to travelers usually involves different parties that have distinctive objectives: travelers are concerned with the benefits of travel time savings, private Information service providers (ISPs) aim to provide marketable Information services from which they can derive a profit, and traffic management centers (TMCs) are responsible for maintaining and improving performance, i.e. minimizing total system travel time. The question is how transportation system managers can leverage this new traffic Information Flow Diagram to improve system performance while considering the tradeoffs among these objectives. The goal of this paper is to study the tradeoffs among the conflicting objectives of different parties and the resulting traffic system performance. We formulate a bi-level model of a complex traffic network. The upper level can be formulated using various objective functions such as the objectives for ISP and TMC. The lower level is a multi-class dynamic traffic assignment (DTA) model that determines dynamic traffic Flows in the network by considering the Information dissemination strategies provided by the upper level model. Numerical results of a small network are provided to illustrate the behavior of this model.

Fan Yang - One of the best experts on this subject based on the ideXlab platform.

  • BILEVEL FORMULATION FOR OPTIMAL TRAFFIC-Information DISSEMINATION
    Transportation Research Record, 2003
    Co-Authors: Fan Yang, Henry X. Liu, Xuegang Ban, Bin Ran
    Abstract:

    With the fast-growing telematics market and maturing traffic-Information services, telematics devices provide a feasible means with which to manage traffic more efficiently. The provision of traffic Information to travelers usually involves different parties that have distinctive objectives: travelers are concerned with benefits of travel-time savings at an affordable service charge, private Information service providers (ISPs) seek to provide marketable Information services from which they can derive a profit, and traffic management centers (TMCs) have the responsibility to maintain and improve system performance, especially to minimize the total system travel time. How transportation system managers can analyze the trade-offs among these objectives and adjust this new traffic-Information Flow Diagram to improve system performance remains an open question. The trade-offs needed among the conflicting multiple objectives of different parties are studied, and traffic system performance is analyzed. The complex traffic network is formulated as a bilevel program. The upper level can be formulated by using various objective functions, such as the objectives for ISP and TMC. The lower level is a multiclass dynamic traffic-assignment model, which determines dynamic traffic Flows in the network by considering the Information dissemination strategies provided by the upper-level model. Numerical results of a small network are provided to illustrate the behavior of this model, and they prove that when there is congestion in the dynamic transportation network, appropriate subscribed rates benefit both all travelers and system performance, while the ISPs' Information influences little without congestion in the transportation network.

  • Bi-Level Formulation for Optimal Traffic Information Dissemination
    2002
    Co-Authors: Fan Yang, Henry X. Liu, Xuegang Ban, Bin Ran
    Abstract:

    With the fast-growing telematics market and maturing traffic Information services, the pervasive use of telematics devices provides a feasible means of more efficiently managing traffic. Providing traffic Information to travelers usually involves different parties that have distinctive objectives: travelers are concerned with the benefits of travel time savings, private Information service providers (ISPs) aim to provide marketable Information services from which they can derive a profit, and traffic management centers (TMCs) are responsible for maintaining and improving performance, i.e. minimizing total system travel time. The question is how transportation system managers can leverage this new traffic Information Flow Diagram to improve system performance while considering the tradeoffs among these objectives. The goal of this paper is to study the tradeoffs among the conflicting objectives of different parties and the resulting traffic system performance. We formulate a bi-level model of a complex traffic network. The upper level can be formulated using various objective functions such as the objectives for ISP and TMC. The lower level is a multi-class dynamic traffic assignment (DTA) model that determines dynamic traffic Flows in the network by considering the Information dissemination strategies provided by the upper level model. Numerical results of a small network are provided to illustrate the behavior of this model.

Xuegang Ban - One of the best experts on this subject based on the ideXlab platform.

  • BILEVEL FORMULATION FOR OPTIMAL TRAFFIC-Information DISSEMINATION
    Transportation Research Record, 2003
    Co-Authors: Fan Yang, Henry X. Liu, Xuegang Ban, Bin Ran
    Abstract:

    With the fast-growing telematics market and maturing traffic-Information services, telematics devices provide a feasible means with which to manage traffic more efficiently. The provision of traffic Information to travelers usually involves different parties that have distinctive objectives: travelers are concerned with benefits of travel-time savings at an affordable service charge, private Information service providers (ISPs) seek to provide marketable Information services from which they can derive a profit, and traffic management centers (TMCs) have the responsibility to maintain and improve system performance, especially to minimize the total system travel time. How transportation system managers can analyze the trade-offs among these objectives and adjust this new traffic-Information Flow Diagram to improve system performance remains an open question. The trade-offs needed among the conflicting multiple objectives of different parties are studied, and traffic system performance is analyzed. The complex traffic network is formulated as a bilevel program. The upper level can be formulated by using various objective functions, such as the objectives for ISP and TMC. The lower level is a multiclass dynamic traffic-assignment model, which determines dynamic traffic Flows in the network by considering the Information dissemination strategies provided by the upper-level model. Numerical results of a small network are provided to illustrate the behavior of this model, and they prove that when there is congestion in the dynamic transportation network, appropriate subscribed rates benefit both all travelers and system performance, while the ISPs' Information influences little without congestion in the transportation network.

  • Bi-Level Formulation for Optimal Traffic Information Dissemination
    2002
    Co-Authors: Fan Yang, Henry X. Liu, Xuegang Ban, Bin Ran
    Abstract:

    With the fast-growing telematics market and maturing traffic Information services, the pervasive use of telematics devices provides a feasible means of more efficiently managing traffic. Providing traffic Information to travelers usually involves different parties that have distinctive objectives: travelers are concerned with the benefits of travel time savings, private Information service providers (ISPs) aim to provide marketable Information services from which they can derive a profit, and traffic management centers (TMCs) are responsible for maintaining and improving performance, i.e. minimizing total system travel time. The question is how transportation system managers can leverage this new traffic Information Flow Diagram to improve system performance while considering the tradeoffs among these objectives. The goal of this paper is to study the tradeoffs among the conflicting objectives of different parties and the resulting traffic system performance. We formulate a bi-level model of a complex traffic network. The upper level can be formulated using various objective functions such as the objectives for ISP and TMC. The lower level is a multi-class dynamic traffic assignment (DTA) model that determines dynamic traffic Flows in the network by considering the Information dissemination strategies provided by the upper level model. Numerical results of a small network are provided to illustrate the behavior of this model.

Henry X. Liu - One of the best experts on this subject based on the ideXlab platform.

  • BILEVEL FORMULATION FOR OPTIMAL TRAFFIC-Information DISSEMINATION
    Transportation Research Record, 2003
    Co-Authors: Fan Yang, Henry X. Liu, Xuegang Ban, Bin Ran
    Abstract:

    With the fast-growing telematics market and maturing traffic-Information services, telematics devices provide a feasible means with which to manage traffic more efficiently. The provision of traffic Information to travelers usually involves different parties that have distinctive objectives: travelers are concerned with benefits of travel-time savings at an affordable service charge, private Information service providers (ISPs) seek to provide marketable Information services from which they can derive a profit, and traffic management centers (TMCs) have the responsibility to maintain and improve system performance, especially to minimize the total system travel time. How transportation system managers can analyze the trade-offs among these objectives and adjust this new traffic-Information Flow Diagram to improve system performance remains an open question. The trade-offs needed among the conflicting multiple objectives of different parties are studied, and traffic system performance is analyzed. The complex traffic network is formulated as a bilevel program. The upper level can be formulated by using various objective functions, such as the objectives for ISP and TMC. The lower level is a multiclass dynamic traffic-assignment model, which determines dynamic traffic Flows in the network by considering the Information dissemination strategies provided by the upper-level model. Numerical results of a small network are provided to illustrate the behavior of this model, and they prove that when there is congestion in the dynamic transportation network, appropriate subscribed rates benefit both all travelers and system performance, while the ISPs' Information influences little without congestion in the transportation network.

  • Bi-Level Formulation for Optimal Traffic Information Dissemination
    2002
    Co-Authors: Fan Yang, Henry X. Liu, Xuegang Ban, Bin Ran
    Abstract:

    With the fast-growing telematics market and maturing traffic Information services, the pervasive use of telematics devices provides a feasible means of more efficiently managing traffic. Providing traffic Information to travelers usually involves different parties that have distinctive objectives: travelers are concerned with the benefits of travel time savings, private Information service providers (ISPs) aim to provide marketable Information services from which they can derive a profit, and traffic management centers (TMCs) are responsible for maintaining and improving performance, i.e. minimizing total system travel time. The question is how transportation system managers can leverage this new traffic Information Flow Diagram to improve system performance while considering the tradeoffs among these objectives. The goal of this paper is to study the tradeoffs among the conflicting objectives of different parties and the resulting traffic system performance. We formulate a bi-level model of a complex traffic network. The upper level can be formulated using various objective functions such as the objectives for ISP and TMC. The lower level is a multi-class dynamic traffic assignment (DTA) model that determines dynamic traffic Flows in the network by considering the Information dissemination strategies provided by the upper level model. Numerical results of a small network are provided to illustrate the behavior of this model.

Takako Nakatani - One of the best experts on this subject based on the ideXlab platform.

  • JCKBSE - A Conceptual Model for Analysis Method of Extracting Unexpected Obstacles of Embedded Systems
    2008
    Co-Authors: Keiichi Katamine, Yasufumi Shinyashiki, Toshiro Mise, Masaaki Hashimoto, Naoyasu Ubayashi, Takako Nakatani
    Abstract:

    This paper proposes a conceptual model for analysis method of extracting unexpected obstacles in order to improve the quality of embedded systems. Although embedded software has become increasingly large in scale and complexity, companies are requiring the software to be developed with in shorter periods of time. This trend in the industry has resulted in the oversight of unexpected obstacles and consequently has affected the quality of embedded software. In order to prevent the oversight of unexpected obstacles, we have already proposed two methods for requirements analysis: the Embedded Systems Improving Method (ESIM) using an Analysis Matrix, and a method that uses an Information Flow Diagram (IFD). However, these analysis methods have been developed separately. This paper proposes the conceptual model including both methods, and clarifies abstraction mechanisms of expert engineers for extracting unexpected obstacles of embedded systems. It also describes a case study and discussion of the domain model.

  • enhancing the esim embedded systems improving method by combining Information Flow Diagram with analysis matrix for efficient analysis of unexpected obstacles in embedded software
    Asia-Pacific Software Engineering Conference, 2007
    Co-Authors: Yasufumi Shinyashiki, Toshiro Mise, Masaaki Hashimoto, Naoyasu Ubayashi, Keiichi Katamine, Takako Nakatani
    Abstract:

    In order to improve the quality of embedded software, this paper proposes an enhancement to the ESIM (embedded systems improving method) by combining an IFD (Information Flow Diagram) with an Analysis Matrix to analyze unexpected obstacles in the software. These obstacles are difficult to predict in the software specification. Recently, embedded systems have become larger and more complicated. Theoretically therefore, the development cycle of these systems should be longer. On the contrary, in practice the cycle has been shortened. This trend in industry has resulted in the oversight of unexpected obstacles, and consequently affected the quality of embedded software. In order to prevent the oversight of unexpected obstacles, we have already proposed two methods for requirements analysis: the ESIM using an Analysis Matrix and a method that uses an IFD. In order to improve the efficiency of unexpected obstacle analysis at reasonable cost, we now enhance the ESIM by combining an IFD with an Analysis Matrix. The enhancement is studied from the following three viewpoints. First, a conceptual model comprising both the Analysis Matrix and IFD is defined. Then, a requirements analysis procedure is proposed, that uses both the Analysis Matrix and IFD, and assigns each specific role to either an expert or non-expert engineer. Finally, to confirm the effectiveness of this enhancement, we carry out a description experiment using an IFD.

  • APSEC - Enhancing the ESIM (Embedded Systems Improving Method) by Combining Information Flow Diagram with Analysis Matrix for Efficient Analysis of Unexpected Obstacles in Embedded Software
    14th Asia-Pacific Software Engineering Conference (APSEC'07), 2007
    Co-Authors: Yasufumi Shinyashiki, Toshiro Mise, Masaaki Hashimoto, Naoyasu Ubayashi, Keiichi Katamine, Takako Nakatani
    Abstract:

    In order to improve the quality of embedded software, this paper proposes an enhancement to the ESIM (embedded systems improving method) by combining an IFD (Information Flow Diagram) with an Analysis Matrix to analyze unexpected obstacles in the software. These obstacles are difficult to predict in the software specification. Recently, embedded systems have become larger and more complicated. Theoretically therefore, the development cycle of these systems should be longer. On the contrary, in practice the cycle has been shortened. This trend in industry has resulted in the oversight of unexpected obstacles, and consequently affected the quality of embedded software. In order to prevent the oversight of unexpected obstacles, we have already proposed two methods for requirements analysis: the ESIM using an Analysis Matrix and a method that uses an IFD. In order to improve the efficiency of unexpected obstacle analysis at reasonable cost, we now enhance the ESIM by combining an IFD with an Analysis Matrix. The enhancement is studied from the following three viewpoints. First, a conceptual model comprising both the Analysis Matrix and IFD is defined. Then, a requirements analysis procedure is proposed, that uses both the Analysis Matrix and IFD, and assigns each specific role to either an expert or non-expert engineer. Finally, to confirm the effectiveness of this enhancement, we carry out a description experiment using an IFD.

  • Enhancing the ESIM (Embedded Systems Improving Method) by Combining Information Flow Diagram with Analysis Matrix for Efficient Analysis of Unexpected Obstacles in Embedded Software
    14th Asia-Pacific Software Engineering Conference (APSEC'07), 2007
    Co-Authors: Yasufumi Shinyashiki, Toshiro Mise, Masaaki Hashimoto, Keiichi Katamine, Naoyasu Ubay, Takako Nakatani
    Abstract:

    In order to improve the quality of embedded software, this paper proposes an enhancement to the ESIM (Embedded Systems Improving Method) by combining an IFD (Information Flow Diagram) with an Analysis Matrix to analyze unexpected obstacles in the software. These obstacles are difficult to predict in the software specification. Recently, embedded systems have become larger and more complicated. Theoretically therefore, the development cycle of these systems should be longer. On the contrary, in practice the cycle has been shortened. This trend in industry has resulted in the oversight of unexpected obstacles, and consequently affected the quality of embedded software. In order to prevent the oversight of unexpected obstacles, we have already proposed two methods for requirements analysis: the ESIM using an Analysis Matrix and a method that uses an IFD. In order to improve the efficiency of unexpected obstacle analysis at reasonable cost, we now enhance the ESIM by combining an IFD with an Analysis Matrix. The enhancement is studied from the following three viewpoints. First, a conceptual model comprising both the Analysis Matrix and IFD is defined. Then, a requirements analysis procedure is proposed, that uses both the Analysis Matrix and IFD, and assigns each specific role to either an expert or non-expert engineer. Finally, to confirm the effectiveness of this enhancement, we carry out a description experiment using an IFD.14th Asia-Pacific Software Engineering Conference (APSEC\u2707), 4-7 Dec. 2007, Aichi, Japa

  • HCI (8) - A suggestion for analysis of unexpected obstacles in embedded system
    Human Interface and the Management of Information. Methods Techniques and Tools in Information Design, 2007
    Co-Authors: Yasufumi Shinyashiki, Toshiro Mise, Masaaki Hashimoto, Naoyasu Ubayashi, Keiichi Katamine, Takako Nakatani
    Abstract:

    In order to improve the quality of embedded software by finding obstacles unanticipated by software specifications, this paper describes a requirement analysis method based on an Information Flow Diagram and experiments using this method, with discussion. Recently, embedded software has become more large-scale and complicated while the development cycle of the software has typically been shortened. This industry trend compromises the quality of embedded software. In order to improve the quality of the software, unexpected obstacles must be carefully analyzed in the specification and design phases. We propose a Diagram-based analysis method to answer this need, and have performed an experiment using the analysis method with an actual product. The results of the experiment made it clear that 1) Novice engineers can construct an Information Flow Diagram under the lead of expert engineers; and 2) The methods by which experts lead novice engineers in the analysis of unexpected obstacles require further refinement.