• Proceedings of the Korea Information Processing Society Conference
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• 2005.11a
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• pp.51-54
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• 2005

최근 도로 네트워크 환경에서 날로 증가하는 교통 수요를 충족시키고 각종 교통 문제를 해결하기 위해서 지능형교통시스템(ITS, Intelligent Transportation System)을 적용하고 있다. 특히, 첨단교통정보 시스템(ATIS, Advanced Traveler Information System)은 개별 차량의 주행을 최적화시키는 시스템으로서 운전자에게 출발지에서 목적지까지 빠르고 쾌적한 주행경로를 제공하는 차량 경로계획 수립을 제공한다. 하지만 이러한 시스템은 도로 구간의 비용으로 정적인 값을 이용하므로 동적으로 변화하는 구간 비용을 가지고 도로 네트워크에서 최단 경로를 제공하기는 어렵다. 따라서, 이 논문에서는 교통 혼잡을 고려한 최단 경로 탐색 연산자를 제안한다. 제안된 연산자는 현재 시간 비용과 과거의 시간 비용 변화 량을 더하여 출발지에서 목적지까지 경로를 탐색하는데 이용한다. 이러한 방법은 시간에 따라 변화하는 도로의 상황을 반영하며 출발지에서 목적지까지의 최단 경로뿐만 아니라 예상 도착 시간을 추정할 수 있다. 또한 제안된 연산자는 효율적인 도로 이용, 물류비용 감소, 응급 상황 대체, 연료 절약 및 환경 오염 감소 등의 장점을 가지며 첨단교통정보시스템에서 응용 될 수 있다.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.3
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• pp.160-173
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• 2013

In this paper, we propose a new visual odometry technique by combining a forward-looking stereo camera and a backward-looking monocular camera. The main goal of the proposed technique is to identify the location of a moving vehicle which travels long distance and comes back to the initial position in urban road environments. While the vehicle is moving to the destination, a global 3D map is updated continuously by a stereo visual odometry technique using a graph theorem. Once the vehicle reaches the destination and begins to come back to the initial position, a map-based monocular visual odometry technqieu is used. To estimate the position of the returning vehicle accurately, 2D features in the backward-looking camera image and the global map are matched. In addition, we utilize the previous matching nodes to limit the search ranges of the next vehicle position in the global map. Through two navigation paths, we analyze the accuracy of the proposed method.

• Journal of the Korea Computer Graphics Society
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• v.23 no.5
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• pp.57-66
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• 2017

In this paper, we suggest a novel physics-based real-time animation technique for vehicles, and introduce an easy and intuitive animation authoring tool which uses our proposed technique. After a user specifies a trajectory of a virtual car as input, our system produces a more accurate simulation faster than a previous research result. This is achieved by a trajectory splitting method based on directional features and a trajectory library. As a result, the user can create not only a car animation including lane changing and passing, but also a crash animation which is a rarely researched topic. Also, we propose a virtual car structure that approximates a real car's structure for real-time simulation, the resulting animation shows high plausibility such as a small vibration which occurs when the virtual car breaks and a deformation of when a car accident happens.

• The Journal of the Korea Contents Association
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• v.6 no.1
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• pp.114-125
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• 2006

Since wireless Internet services and small mobile communication devices come into wide use as well as the use of GPS is rapidly growing, researches on moving object, whose location information shifts sequently in accordance with time interval, are being carried out actively. Especially, the researches on vehicle moving object are applied to Advanced traveler information system, vehicle tracking system, and distribution transport system. These systems are very useful in searching previous positions, predicted future positions, the optimum course, and the shortest course of a vehicle by managing historical data of the vehicle movement. In addition, vehicle historical data are used for distribution transport plan and vehicle allocation. Vehicle historical data are stored at regular intervals, which can have a pattern. For example, a vehicle going repeatedly around a specific section follows a route very similar to another. If historical data of the vehicle with a repeated route course are stored at regular intervals, many redundant data occur, which result in much waste of storage. Therefore this thesis suggest a vehicle historical data store scheme for vehicles with a repeated route course using similar trajectory which efficiently store vehicle historical data.

• Journal of the Korea Society for Simulation
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• v.16 no.3
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• pp.1-9
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• 2007

Travel time between two points depends upon whether it is a rush hour or not in metropolitan area. It is true that there is big differences on the time required to get through the area whether going in busy morning or near noon. Another issue is that there exist many delivery points which closely located each other; so no need to consider traveling hours among these points. We designed an efficient procedure to reduce the complexity by considering closely located delivery points as one big delivery point. A computer simulation model is constructed for comparison purposes of the developed heuristic with the optimum solution.

• Journal of Intelligence and Information Systems
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• v.15 no.1
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• pp.1-14
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• 2009

The Capacitated Vehicle Routing Problem (CVRP) is the problem that the vehicles stationed at central depot are to be optimally routed to supply customers with demands, satisfying vehicle capacity constraints. The CVRP is the NP-hard as it is a natural generalization of the Traveling Salesman Problem (TSP). In this article, we propose the heuristic algorithm, called the bisection seed detection method, to solve the CVRP. The algorithm is composed of 3-phases. In the first phase, we work out the initial cluster using the improved sweep algorithm. In the next phase, we choose a seed node in each initial cluster by using the bisection seed detection method, and we compose the rout with the nearest node from each seed. At this phase, we compute the regret value to decide the list of priorities for the node assignment. In the final phase, we improve the route result by using the tabu search and exchange algorithm. We compared our heuristic with different heuristics such as the Clark-Wright heuristic and the genetic algorithm. The result of proposed heuristic show that our algorithm can get the nearest optimal value within the shortest execution time comparatively.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.2
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• pp.454-461
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• 2005

Car navigation system which is killer application fuses map management techniques into CPS techniques. Even if the existing navigation systems are designed for the shortest path, they are not able to cope efficiently with the change of the traffic flow and the bottleneck point of road. Therefore, it is necessary to find out shortest path algorithm based on time instead of distance which takes traffic information into consideration. In this paper, we propose a optimal path search algorithm based on the traffic information. More precisely. we introduce the system architecture for finding out optimal paths, and the limitations of the existing shortest path search algorithm are also analyzed. And then, we propose a new algorithm for finding out optimal path to make good use of the orientation of the collected traffic information.

• Journal of Internet Computing and Services
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• v.3 no.6
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• pp.35-41
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• 2002

The Car Navigation System(CNS) requires lots of memory and calculating time because it works on the large and complex digital map. And the traffic circumstances vary time by time, so the traffic informations should be processed if we want to get mere realistic result. This paper proposes an effective path searching algorithm which uses less memories and calculating time by applying directional information between the starting place and destination place and by using realtime traffic informations.

• Proceedings of the Korea Information Processing Society Conference
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• 2016.04a
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• pp.733-734
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• 2016

무인 차량의 자율 주행을 위해 장애물 회피, 주행 가능 도로 판단 등의 기술이 연구되고 있다. 이러한 연구를 실제 환경에서의 자율 주행에 활용하기 위해서는 주변 환경에 동적으로 움직이는 장애물의 위치를 고려할 필요가 있다. 본 연구는 차량에 탑재된 LIDAR로부터 획득한 포인트의 분포 변화를 이용하여 차량 주변에 동적 장애물이 존재하는 지역을 검출하는 방법을 제안한다. 해당 방법은 포인트에 대한 통계치를 활용하여 동적 객체가 존재하는 영역을 추정함으로써 동적 객체 영역을 고속으로 탐색할 수 있다.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1949-1951
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• 2003

본 논문에서는 수신 측에서 Digital Beam Forming 기술을 응용한 새로운 개념의 차량 충돌 방지용 레이더를 소개한다. 이는 기존의 기술보다 더 넓은 범위에서 차량 탐색이 가능하고, 고해상도를 가지면서, 한 측정 단위 셀 내에서 여러 개의 물체를 찾아낼 수 있다. 제안된 방법은 기존 차량충돌 방지용 레이더의 송수신 안테나에 있어서의 많은 제약을 극복할 수 있는 방법이다.