• Journal of Korean Society of Transportation
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• v.21 no.3
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• pp.97-106
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• 2003

When a route choice is done under uncertainty, a driver has some expectation of traffic conditions that will occur according to the route chosen. This study tries to build a framework in which we can observe the learning behavior of the drivers' expectations of the travel time under nonstationary environment. In order to investigate how drivers have their subjective expectations on traffic conditions in response to public information, a numerical experiment is carried out. We found that rational expectations(RE) formation about the route travel time can be expressed by the adaptive expectation model when the travel time changes in accordance with the nonstationary process which consists of permanent shock and transient shock. Also, we found that the adaptive parameter of the model converges to the fixed value corresponding to the route conditions.

• Proceedings of the KAIS Fall Conference
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• 2008.05a
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• pp.326-328
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• 2008

본 논문에서는 지능형 유도시스템의 한계점에 대해 분석을 진행하였고 보완방법을 제안하였다. 지능형 유도시스템의 화재시 안전하고 효과적인 피난경로를 선택하는 방법에서 기존에는 비상출입구까지의 최단거리를 선택하였으나 본 연구에서는 경로의 특성을 고려하여 효용함수를 산출하여 경로를 선택하는 방법을 제안하였다.

• Journal of Korean Society of Transportation
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• v.26 no.1
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• pp.145-153
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• 2008

Existing shortest-path algorithms mainly consider a single attribute. But traveler actually chooses a route considering not single attribute but various attributes which are synthesized travel time, route length, personal preference, etc. Therefore, to search the optimal path, these attributes are considered synthetically. In this study route searching algorithm which selects the maximum utility route using discrete choice model has developed in order to consider various attributes. Six elements which affect route choice are chosen for the route choice model and parameters of the models are estimated using survey data. A multinomial logit models are developed to design the function of route choice model. As a result, the model which has route length, delay time, the number of turning as parameter is selected based on the significance test. We use existing shortest path algorithm, which can reflect urban transportation network such as u-turn or p-turn, and apply it to the real network.

• 한국HCI학회:학술대회논문집
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• 2008.02a
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• pp.298-303
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• 2008

User adaptive services have been important features in many applications. To provide such services, various techniques with various kinds of data are being used. In this paper, we propose a method to analyze user's past moving paths for predicting the goal position and the path to the goal by observing the user's current moving path. We develop a spatio-temporal similarity measure between paths. We choose a past path which is the most similar to the current path using the similarity. Based on the chosen path, user's spatio-temporal position is estimated. Through experiments we confirm this method is useful and effective.

• Journal of the Korean Institute of Intelligent Systems
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• v.16 no.5
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• pp.568-574
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• 2006

User adaptive services have been important features in many applications. To provide such services, various techniques with various kinds of data are being used. In this paper, we propose a method to analyze user's past moving paths and predict the goal position and the path to the goal by observing the user's current moving path. We develop a spatiotemporal similarity measure between paths. We choose a past path which is the most similar to the current path using the similarity. Based on the chosen path, user's spatiotemporal position is estimated. Through experiments we confirm this method is useful and effective.

• Proceedings of the Korean Information Science Society Conference
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• 2005.07b
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• pp.613-615
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• 2005

사용자와 관련한 환3 데이터로부터 유용한 정보를 만들어 내기 위하여 다양한 형태의 데이터를 이용한 다양한 방법이 연구되고 있다. 그 중 사용자의 이동 경로는 공간상의 이동 위치를 예측하고 유용한 서비스를 제공하는데 유용하게 사용될 수 있다. 본 논문에서는 사용자의 이동 경로에 대한 분석과 예측기술을 제안한다. 환경으로부터 발생한 사용자의 이동 경로를 수집하고 수집된 데이터는 이동 경로 선택(Path Selection) 방법을 이용하여 유사성이 가장 높은 경로를 선택하여 준다. 선택된 경로는 시간에 따른 공간 정보 표현 및 위치에 따른 시간 예측 서비스를 위하여 사용가능 하며, 실험을 통하여 유사성이 높은 이동 경로를 선택하는 모습을 확인하였다.

• Journal of Korean Society of Transportation
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• v.28 no.1
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• pp.77-86
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• 2010

The study developed physical distribution channel choice models reflecting decision making of the firms and studied how choice decision factors influence selection of distribution channel. The distribution channel survey data in Korea was used to do empirical study. As a choice set, distribution channels were classified into two main choice channels: direct and indirect channels. In addition, indirect channels were classified into other three channels according to the type of intermediate point: distribution center, wholesale store, and agency. This study developed choice models by applying both binary and multinomial logit model with various set of factors. The results showed that the developed logit models seemingly reflect distribution channel choice behaviors. The hypothesis tests on how each factor influences choice of distribution channel were performed and discussed as well.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.8A
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• pp.581-590
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• 2003

This paper proposes the routing path selection mechanism for source routing-based PtMP (Point-to-Multipoint) call in ATM switching system. Especially, it suggests PtMP routing path selection method that can share the maximum resource prior to the optimal path selection, guarantee the reduction of path calculation time and cycle prevention. The searching for the nearest branch point from destination node to make the maximum share of resource is the purpose of this algorithm. Therefore among neighbor nodes from destination node by back-tracking, this algorithm fixes the node crossing first the node on existing path having the same Call ID as branch node, constructs the optimal PtMP routing path. The optimal node to be selected by back-tracking is selected by the use of Dijkstra algorithm. That is to say, PtMP routing path selection performs the step of cross node selection among neighboring nodes by back-tracking and the step of optimal node selection(optimal path calculation) among neighboring nodes by back-tracking. This technique reduces the process of search of routing information table for path selection and path calculation, also solves the cycle prevention easily during path establishment.

• KSCI Review
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• v.15 no.1
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• pp.31-35
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• 2007

많은 센서 네트워크 응용 분야에서 센서 노드들은 무인 환경에서 배치되므로, 물리적인 공격들과 노드가 가진 암호 키들이 손상되기 쉬운 취약성을 가진다. 위조 보고서는 훼손된 노드를 통해서 잠입할 수 있고 이 위조보고서는 거짓 경보를 유발할 수 있을 뿐만 아니라, 네트워크의 제한된 에너지의 고갈을 야기한다. 이러한 문제점을 보안하기 위해 Ye 등은 통계적 여과 기법을 통해서 위조 보고서를 탐지하고 도중에 여과시키는 방안을 제시한다. 이 제안된 방안에서 각 노드는 검증을 위한 일정한 양의 정보를 가지며. 탐지 능력은 라우팅 경로의 선택에 의해 영향을 받는다. 본 논문에서는, 통계적 여과 기법의 위조 보고서 탐지 능력을 향상시키기 위한 경로선택 방법을 제안한다. 각 노드는 베이스 스테이션으로부터 정해지는 각 경로들의 위조 보고서 탐지 능력을 평가하고 위조 보고서 침투 공격에 대해 가장 안전한 경로를 선택한다.

• Journal of Navigation and Port Research
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• v.39 no.1
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• pp.29-35
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• 2015

As the numbers of users of domestic passenger ships increased up to 14.5 millions at 2012, the numbers of ships accidents also increased as 2 times than ever. It will be very important to develop technologies related with safety design for onboard passengers and disclose the potential problems. This study performed consciousness survey on ordinary peoples' way finding who have not got any regular anti-disaster training, to develop evacuation models for evacuation feasibility studies. Followings are the results answered by 83 participants for 33 way finding questions. Respondents selected right ways more than 6~18% for 2 ways like T type, U type, Y type passages. But when there are some walkers and/or runners, respondents preferred to select the way where walkers or runners are. And more over the ratio of the ways that runners are on is comparatively higher than walkers. On 'ㅏ'type, 'ㅓ'type and 3 way type passages, even though the walkers and/or runners are affected to answerers, straight way were most preferred. And it is clear that peoples like bright passages. On the other hands, peoples responded as they like right, downward and near stairs more than left, upward and far stairs, respectively. and very few selected escalator and elevator for as evacuation stairs.