• Journal of Korean Society of Transportation
• /
• v.35 no.1
• /
• pp.50-62
• /
• 2017

As the use of private cars increases along with the technological advancement in the automobile industries and their capabilities to supply, a wide range of issues are followed including the increase in traffic congestion costs, pavement damages and more. In spite of consistent effort to resolve such urban traffic problems, the modal share rate of private cars continuously increases, thus it is becoming more important to explore the ways to enable drivers to take reasonable measures, in self-motivated manner, by taking part of the transportation demand management policy rather than to rely on the strict enforcement of control policy. Considering that the urban transportation infrastructures are in much better shape than before, it is necessary to implement Mobility Management (MM) that induces reasonable usage of private cars by promoting the change in one's consciousness and behavior through communication. Hence, the research studies the factors that influence the mobility through the survey targeting the citizens of Busan on their awareness on the former transportation demand management policy, to explore the ways to motivate the citizens' involvement in reducing the use of private cars as a measure of Mobility Management.

• Land and Housing Review
• /
• v.2 no.3
• /
• pp.217-226
• /
• 2011

The Seoul Metropolitan Government is striving to minimize the amount of traffic according to the supply of apartment houses along with the solution of housing shortage for the low income people through high density development near the subway area. Therefore, a stronger policy is necessary to control the traffic of the passenger cars in a subway area for the successful high density development focusing on public transportation, and especially, the estimation of the demand of cars with high reliability is necessary to control the demand of parking such as the limited supply of parking lot. Accordingly, this study developed car ownership forecasting model using Look-up Table among category analyses which are easy to be applied and have high reliability. The estimation method using Look-up-Table is possible to be applied to both measurable and immeasurable types, easy to accumulate data, and features the flexible responding depending on the changes of conditions. This study established Look-up-Table model through the survey of geographical location, the scale of housing, the accessible distance to a subway station and to a bus station, the number of bus routes, and the number of car owned with data regarding 242 blocks in Seoul City as subjects.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.13 no.6
• /
• pp.2964-2985
• /
• 2019

Global data center IP traffic is expected to reach 20.6 zettabytes (ZB) by the end of 2021. Intra-data center networks (Intra-DCN) will account for 71.5% of the data center traffic flow and will be the largest portion of the traffic. The understanding of traffic distribution in IntraDCN is still sketchy. It causes significant amount of bandwidth to go unutilized, and creates avoidable choke points. Conventional transport protocols such as Optical Packet Switching (OPS) and Optical Burst Switching (OBS) allow a one-sided view of the traffic flow in the network. This therefore causes disjointed and uncoordinated decision-making at each node. For effective resource planning, there is the need to consider joining the distributed with centralized management which anticipates the system's needs and regulates the entire network. Methods derived from Kalman filters have proved effective in planning road networks. Considering the network available bandwidth as data transport highways, we propose an intelligent enhanced SDN concept applied to OBS architecture. A management plane (MP) is added to conventional control (CP) and data planes (DP). The MP assembles the traffic spatio-temporal parameters from ingress nodes, uses Kalman filtering prediction-based algorithm to estimate traffic demand. Prior to packets arrival at edges nodes, it regularly forwards updates of resources allocation to CPs. Simulations were done on a hybrid scheme (1+1) and on the centralized OBS. The results demonstrated that the proposition decreases the packet loss ratio. It also improves network latency and throughput-up to 84 and 51%, respectively, versus the traditional scheme.

• Journal of the Korea Society of Computer and Information
• /
• v.14 no.12
• /
• pp.41-53
• /
• 2009

In this paper, we propose the system structure and technologies to implement a business model for an intelligent traffic facility management system based on ubiquitous technology. The business model includes the service functions, service structure, business process, and demand and supply relationship among the participants in this model. We also propose an approach to implementing the model. This includes the network, infrastructure and platform to be used for system composition. We then present the results from an analysis by comparison of different technologies and an adequate technology structure. Finally, this paper may present guidelines to managing traffic facilities.

• Journal of Korea Multimedia Society
• /
• v.18 no.2
• /
• pp.189-198
• /
• 2015

Despite the fact that traffic engineering techniques have been comprehensively utilized in the past to enhance the performance of communication networks, the distinctive characteristics of Software Defined Networking (SDN) demand new traffic engineering techniques for better traffic control and management. Considering the behavior of traffic, large flows normally carry out transfers of large blocks of data and are naturally packet latency insensitive. However, small flows are often latency-sensitive. Without intelligent traffic engineering, these small flows may be blocked in the same queue behind megabytes of file transfer traffic. So it is very important to identify large flows for different applications. In the scope of this paper, we present an approach to detect large flows in real-time without even a short delay. After the detection of large flows, the next problem is how to control these large flows effectively and prevent network jam. In order to address this issue, we propose an approach in which when the controller is enabled, the large flow is mitigated the moment it hits the predefined threshold value in the control application. This real-time detection, marking, and controlling of large flows will assure an optimize usage of an overall network.

• Journal of Korean Society of Transportation
• /
• v.23 no.4 s.82
• /
• pp.57-69
• /
• 2005

The goal of this paper is to develop freeway Origin-Destination (OD) demand estimation model using real-time traffic data collected from Freeway Traffic Management System (FTMS). In existing research, the micro-simulation models had been used to get a link distribution proportion by time process. Because of hi-level problem between the traffic flow model and the optimal OD solution algorithm, it is difficult for the existing models to be loaded at FTMS. The formulation of methodology proposed in this paper includes traffic flow technique to be able to remove the bi-level problem and optimal solution algorithm using a genetic algorithm. The proposed methodology is evaluated by using the real-time data of SOHAEAN freeway, South Korea.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.30 no.1
• /
• pp.1-15
• /
• 2005

In this paper, we deal with a mesh network design problem arising from the deployment of WDM for the optical internet. The mesh network consists of mesh topology for satisfying traffic demand while minimizing the cost of WDM, OXC, and fiber cables. The problem seeks to find an optimal routing of traffic demands in the network such that the total cost is minimized. We formulate the problem as a mixed-integer programming model and devise a tabu search heuristic procedure. Also we develop an optical internet design system that implements the proposed tabu search heuristic procedure. We demonstrate the computational efficacy of the proposed algorithm, compared with CPLEX 8.0.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2002.05a
• /
• pp.426-433
• /
• 2002

This paper deals with an offline routing problem, which can be used as an explicit routing procedure in MPLS(Multiprotocol Label Switching) network, for traffic engineering. This problem is formulated as an MIP(Mixed Integer Programming) with the objective function which is to minimize the sum of the maximum link utilization for load balancing (link utilization) and the routing cost. Constraints arc composed of link capacity restriction and demand requirement that has origin-destination pair, bandwidth requirement and hop restriction. The problem is proved to be NP-hard so that the Lagrangean relaxation method is applied to propose a Lagrangean heuristic. To test the effectiveness & efficiency of the proposed algorithm, computational experiments are performed with numerical instances. The experiment results show that the proposed algorithm solves the problem within a reasonable time.

• The Transactions of the Korea Information Processing Society
• /
• v.6 no.3
• /
• pp.681-691
• /
• 1999

It was already proved that ATM stability and flexibility of service application, but because of the various characteristics of traffics and the QoS on user demand caused by them, there are a lot of researches for traffic management method. However, there are a few of researches for ATM routing method acting on traffic management practically. In this paper, we focus on multi-path routing method transporting cells with multiple paths and compare this method with existing single path routing method and analyze multi-path routing method into three elements with simple formula and propose anew methods improving the performance of ATM routing and simulate these methods.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.915-923
• /
• 2011

Our country is promoting the introduction of new means of transportation due to insufficient supply according to the existing demand of road traffic. Among them, manless light railroad transit is settled down as the most definite alternative. However, new traffic systems such as manless light railroad have certain difference between characteristics of hardware and software and subway system. Therefore, there will be many differences compared to the existing contingency system when accidents occur. Railway management organization has to establish railway contingency plan and acquire permission from the minister of the Ministry of Land, Transport, and Maritime Affairs. However, as commercial transportation is available, a new traffic system also should establish contingency plan. Therefore, the establishment of systematic contingency plan is suggested in order to analyze characteristics of manless light railroad in the beginning of introduction and to make contingency response available.