• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.4
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• pp.10-18
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• 2012

This paper develops a decentralized advanced traveler information system (ATIS) under the connected vehicle environment, recently regarded as one of most promising tools in Intelligent Transportation Systems (ITS). The performance of the proposed ATIS is reinforced by introducing autonomous automatic incident detection (AAID) function. The proposed ATIS is implemented and tested using an off-the-shelf microscopic simulation model (VISSIM) on a simple traffic network under idealized communication conditions. A key attribute of this experiment is the inclusion of a non-recurrent traffic state (i.e., traffic incident). Simulation results indicate that the ATIS using V2V communication is efficient in saving drivers' travel time and AAID plays an important role in improving the effectiveness of the system.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.1683-1687
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• 2009

USN(Ubiquitous Sensor Network)은 어디든지 부착 가능한 센서와의 자동 교류를 통해 대상의 환경적 정보를 습득, 저장, 처리하여 지식, 정보 서비스를 언제, 어디서나, 누구에게나 제공하는 최신 네트워크이다. USN은 교통, 기상 그리고 환경 등의 공동 정보를 제공할 수 있는 차세대 국가적인 인프라로 개발될 것이다. 기존에 연구되고 있는 무선 네트워크가 높은 데이터 전송률 및 처리성능을 기본으로 하는 컴퓨팅에 초점을 둔 반면에, 센서 네트워크는 강우량 감지와 같은 애플리케이션에서 대부분 짧은 시간동안 적은 양의 전송만 수행하게 된다. 센서 네트워크는 유비쿼터스 컴퓨팅 기술을 실현하기 위한 핵심 기술적 인프라라고 할 수 있다. 본 연구에서는 USN의 정의와 기초 기술에 대한 내용을 기술하고, 센서 네트워크를 위한 통신기술, 고속 데이터 전송을 위한 광대역 통합망, 상황 인식 및 실시간 데이터 처리를 위한 미들웨어 등 USN 기반기술에 대하여 기술하였다. 또한 최근 서비스 및 기술의 개발, 표준화 동향을 분석함으로써 USN을 수문 정보 분야에 적용시킬 수 있는 방법들을 검토하였다. 더 나아가, 현존하는 USN 모델 사업 분석을 바탕으로 수자원분야에서의 기술적인 적용 가능성에 대해 검토해본다.

• Journal of Korean Society of Transportation
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• v.28 no.6
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• pp.75-84
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• 2010

Controlled traffic intersection is critical point in terms of transportation network performance, where the most of traffic congestion arises. One of the most important and favorable measure of effectiveness in the signal controlled intersection is approach delay. Although lots of efforts to develop traffic delay estimation models have been made throughout the years, most of them were focusing on homogeneous traffic flow. The purpose of this research is to develop a traffic delay estimation model for traffic flow mixed with bus based on the horizontal shockwave theory. Traffic simulation is performed to test the adaptation level of the model in generic environment. The result shows that the delay increases with increasing bus traffic. Overall model accuracy comparing simulation result is acceptable, that shows the error range around 10 percent.

• Journal of Korean Society of Transportation
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• v.25 no.3
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• pp.87-97
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• 2007

This paper proposes drivers' rational belief formation under a bounded traffic environment. This is to escape the criticism that excessive rationality (e.g., a driver's calculating ability and memory capacity) is required of drivers. Under bounded traffic environments. drivers do not have structural knowledge of traffic conditions and others' decisions. Simulations are carried out using a program coded in C. Consequently, the author found the learning process of drivers and the value of information can be differentiated by route conditions and the characteristics of driver groups. Also, it was found that rational drivers form different beliefs about traffic conditions even though they have the same traffic environment in a bounded traffic environment.

• Journal of the Economic Geographical Society of Korea
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• v.12 no.4
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• pp.540-556
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• 2009

The hub and spoke network is a critical network-based infrastructure that is widely applied in current transportation and telecommunications systems, including Internets, air transportation networks and highway systems. This main idea of hub location models is to construct a network system which achieves the economy of scale of flows. The main purpose of this study is to introduce new hub location problems that take into account network reliability. Two standard models based on assignment schemes are proposed, and a minimum threshold model is provided as an extension in terms of hub network design. The reliability and interaction potentials of 15 nodes in the U.S. are used to examine model behaviors. According to the type of models and reliability, hubs, and minimum threshold levels, relationships among the flow economy of scale, network costs, and network resiliency are analyzed.

• Spatial Information Research
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• v.14 no.2 s.37
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• pp.245-260
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• 2006

A practical use of the location information and user requirement are increased in a mobile environment which supports the portability. And Various service which GIS is related with a Spatial DB have been processed. Generally, logical relation of a traffic network which organizes the Road DB uses a basic node-link structure. In this way, Designed structure can not be flexible at various model apply and are not efficient with a database retrieval in a maintenance management side. In this research, We supplement with the problem of a existing network model and the limitation of the building through the design of a network model which uses dynamic segmentation. And we tried to implement efficient hierarchy model at the retrieval of the network and presentation. Designed model supports a stage presentation of various level and a hierarchy entity relation and We are expected to supplement a network spatial modelling function which the GIS has.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2009.04a
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• pp.273-274
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• 2009

도로네트워크 데이터는 교통 정보, 경로 안내서비스 등 실시간 정보제공을 위해 차량 항법용 데이터에서 가장 핵심적인 영역에 해당하며 효율적인 관리와 유지가 필수적이다. 기존 파일 기반 시스템인 미디어 포맷(KIWI, GDF 등)에서는 콤팩트한 데이터 구성으로 읽기 위주의 빠른 매체 접근 등에 좋은 이점이 있지만, 최근 모바일 시스템 환경에 DBMS를 활용한 위치 기반 서비스(LBS)에 대한 관심이 증가 하고 있다. 이에 본 연구에서는 임베디드 DBMS를 이용하여 네트워크의 계층성을 지원하는 데이터 모델과 이를 활용한 탐색 알고리듬을 설계하고 프로토타입 시스템을 구현하였다. 특히 대규모 도로망의 원거리 탐색을 대상으로 메모리 구성과 탐색 시간 측면에서 일반 영역 탐색방법과 계층 탐색방법의 검색 결과를 비교하여 계층 탐색 방법의 효율성을 검증하였다.

• Journal of the Korean Geographical Society
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• v.39 no.4
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• pp.585-601
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• 2004

The purpose of this paper is to examine the change of Korean land transportation system and pattern during 1905-1911 concentrated on road construction so-caued ‘Sinjak-ro’. As conclusions, modem road or ‘Sinjak-ro’ started from modem port to inner hinterland where economic resource or regional center located. A trunk railroad running through Korea Peninsula from Busan to Sinuiju(border between China) is opened its complete operation in 1906 by Japanese investment, when no ‘Sinjak-ro’ road construction begun. Thus from the beginning, railroad station also became important starting point of ‘Sinjak-ro’ as seaports. Before the Japanese annexation of Korea, the ‘Sinjak-ro’ road was constructed mainly between seaport or station, where Japanese commercial settlement located, and hinterlands to help their economic invasion. This study could not deal with other modem transportation systems such as railroads and waterways. It is necessary to examine whole changes of modern transportation systems in this age so that we would comprehend modernization feature of Korea from the viewpoint of transportation history.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.1
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• pp.122-127
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• 2009

In this paper, it is reviewed security architecture and proposed security model about secure aeronautical system, which is considering in the cynical research topics out of aeronautical traffic system. The reviewed contents is treated about security model fur domestic aeronautical system with international security technology trends in the basis of security technology related aeronautical services. In the security framework of aeronautical communication network, it is analyzed data link security technology between air and ground communication, and security architecture in according to aeronautical system, and presented security architecture of U information HUB model. The security architecture of U-information HUB includes the internetworking scope of airline, airport network, airplane network, and related government agency, etc.

• Journal of Korean Society of Transportation
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• v.33 no.2
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• pp.145-158
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• 2015

A network connectivity has been regarded as a key element to strengthen a business competitive power in the aviation industry, so many airport authorities try to attract the new airlines and scheme out new air routes. With this trend, a study for an induced travel demand estimation methodology is needed. This study introduces a demand estimation method, especially for a new air route to a promising destination. With the results of previous studies, the derived demand is classified into four types - Local, Beyond, Behind and Bridge. The explanatory variables are established for each type of demand and the main independent variables are composed of distance, ratio of detour, and relative capacity compared with other airports. The equations using such variables and statistically significant coefficients are suggested as the model to make an estimation of derived demand for a new route. Therefore this study will be expected to take an initial step for all related parties to be involved more deeply into developing new air routes to enhance network connectivity.