• Journal of Korea Society of Industrial Information Systems
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• v.15 no.2
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• pp.23-30
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• 2010

This paper presents implementation details of car communications system based on V2I2V model over broadband wireless networks including WCDMA, HSDPA and WiBro. Also, we measures the major performance metrics such as Round Trip Time, end-to-end latency and others between in-vehicle client and location management system by driving across urban areas in Daegu city. Analysis of experimental results would be helpful to consider the applicability of traffic safety services using V2I2V-based car communications over various broadband wireless networks.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.49 no.4
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• pp.53-58
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• 2012

The roadside unit (RSU) collects vehicle information from vehicles in the intelligent transportation system (ITS). The vehicle density on the road within the communication range of a RSU is a time varying parameter. The higher the vehicle density, the more vehicle information can be collected. Therefore, the probability of packet collision will be raised. In this paper, an adaptive transmission scheme is proposed to improve the probability of packet reception rate by changing the data rate and transmission period according to the vehicle density. The performance of IEEE 802.11p MAC protocol that is a standard for vehicular communications is evaulated in terms of the vehicle density with the ns-2,33 simulator.

• Journal of Korean Society of Transportation
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• v.20 no.4
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• pp.177-185
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• 2002

본 논문의 목적은 링크통행시간 자료를 수집하는 시스템에서 소요 프로브차량대수에 영향을 주는 요소들을 규명하고. 최적의 소요 프로브차량대수를 결정하는 모형을 개발하는데 있다. 자가용승용차, 택시, 버스, 택배차량 등 여러 종류의 차량들이 프로브차량으로 사용될 수 있다. 그러나 일정한 정확도 이상의 교통정보를 수집하기 위해서 얼마나 많은 프로브차량이 필요한지에 대한 연구는 그다지 깊이 있게 이루어지지 않았다. 적정 소요 프로브차량대수는 링크통행시간 자료수집 기술 수집대상 링크의 공간적 범위, 프로브차량의 종류 및 운행 특성, 자료수집 시스템의 신뢰도, 수집되는 자료의 정확도 등에 영향을 받게 된다. 소요 프로브차량대수를 결정하는 링크당 평균 통행시간 자료수, 프로브차량 밀도의 최소 확률, 그리고 자료 미수집링크의 허용비율의 3가지 결정기준이 정의되었다. 또한 이러한 결정기준에 대해 소요 프로브차량대수를 산출하는 모형이 개발되었다. 일반적으로 주기당, 링크당 평균 필요 통행시간 자료수$(d_R)$, 단위길이당 프로브차량의 대수 또는 밀도$(n_{min} or {\alpha})$, 일정 프로브차량밀도 이상의 확률($\beta$), 그리고 자료 미수집링크의 비율($\gamma$)이 클수록 소요 프로브차량대수는 증가한다. 민간 교통정보회사의 통행시간 수집시스템에서 소요 프로브차량대수를 산정하는 사례연구가 수행되었으며, 여러가지 조건에서 소요 프로브차량대수가 산출되었다.

• Proceedings of the Korean Information Science Society Conference
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• 2001.04b
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• pp.511-513
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• 2001

지능형 교통 시스템(ITS)은 1) 도로의 상황 분석과 2) 위반 차량의 검지를 자동으로 수행하여 원활한 교통 제어를 제공하는 목적을 가지고 있다. 본 논문에서는 교차로에서 위반 차량을 검지하기 위하여 도로위의 차량 검지하고 차량의 진행 경로를 추적하는 기법으로 주간에는 배경 영상을 사용하지 않고 프레임간의 차를 이용하여 차량의 움직임 정보를 추출하고 야간에는 전조등을 검출하여 차량을 추적하는 기법으로 주간의 겨우 차량의 움직임만을 감지하므로 칼만 필터(Kalman Filter) 등에 의한 예측이 불가능하므로 현재 위치와 진행방향으로 움직임 정보를 추적하는 기법을 제안한다. 제안하는 기법은 주간 그림자의 영향과 야간의 난반사의 영향을 제거할 수 있고 입력 영상을 320x240으로 축소하여 초당 10프레임이상으로 처리하므로 정확한 차량의 움직임을 추적할 수 있다.

• Journal of Korea Society of Industrial Information Systems
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• v.14 no.2
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• pp.51-58
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• 2009

In this paper, a system which uses Bluetooth and Zigbee wireless communication and mobile device is designed. The temperature within vehicle and the distance betweeen the vehicle and the obstacle is measured by ultrasonic sensor system. The measured data is sent to the mobile PDA and displayed to assist safe driving.

• Journal of KIISE:Information Networking
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• v.34 no.5
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• pp.340-347
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• 2007

Vehicle safety service can be effectively achieved with inter-vehicle communication technologies, in which moving vehicles transmit a safety related urgency information such as traffic accidents, sudden stops, obstacle appearance etc. They usually utilize a broadcast of message propagation method because the communicating vehicles are not known each other. The pure broadcasting scheme does not satisfy the requirements of vehicle safety communication service due to the transmission delay with frequent message collisions. To resolve this problem, this paper presents a group based propagation method for the multi-hop transmission, in order to deliver an urgency message to the reasonable size of vehicle troop. A group header is elected in considering of the position information of vehicles and radio transmission range. And a vehicle equivalent group is formed with the header. With benefits of the group based transmission, it is possible to minimize the unnecessary transmission and the possibility of message collisions. Simulation results show that the message propagation performance is so stable regardless of vehicle's congestion degree.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.11
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• pp.2471-2477
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• 2010

lately, vehicle blackbox increasing importance and usability Is needed accuracy and variety of information. because, blackbox help to analyze the exact cause of the accident and use as objective evidence in vehicle-related crime. In the paper, to overcome the limitations of the existing black box, use various sensors and vehicle information blackbox store current state of the vehicle with OBD-II protocol using vehicle state information and store exact current location and direction information of the vehicle with Gyro sensor and GPS and use global time of GPS for synchronization of information. In addition, blackbox back the information up with wifi. because, when blackbox damaged, dirvers were able to verify the information.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.14 no.3
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• pp.223-230
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• 2021

Currently, self-driving vehicles are on the verge of commercialization after testing. However, even though autonomous vehicles have not been fully commercialized, 81 accidents have occurred, and the driving method of vehicles to avoid accidents relies heavily on LiDAR. In order for the currently commercialized 3-level autonomous vehicle to develop into a 4-level autonomous vehicle, more information must be collected than previously collected information. Therefore, this paper proposes a Driving Situation Judgment System (DSJS) that accurately calculates the crisis situation the vehicle is in by useing the roughness of the road and the state of the passengers of surrounding vehicles including road information and weather information collected from existing autonomous vehicles. As a result of DSJS's PDM experiment, PDM was able to classify passengers 15.52% more accurately on average than the existing vehicle's passenger recognition system. This study can be a basic research to achieve the 4th level autonomous vehicle by collecting more various types than the data collected by the existing 3rd level autonomous vehicle.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.9
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• pp.1539-1546
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• 2008

In the present age, a vehicle works important part in our lives and economical domain that transport people, freights, and everything. And both of its number and value are increasing more and more. But user's convenience, control system could not be archived improvement than technological success. In this paper, we suggest some kinds of administrative agendas; simplifying executive processes, designing vehicle information system using by RFID which includes Ubiquitous skill and optical communication network. Especially, this paper suggests public vehicle control model which ran simplify every executive processes of vehicle's life in the newest method. There are many kinds of RFID applicative products about transportation. And a dual invest should be interrupted for economical purpose. So we also proposes some way for problems of these types.

• Proceedings of the Korea Information Processing Society Conference
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• 2022.11a
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• pp.156-158
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• 2022

차량이 사용자에게 다양한 서비스를 제공하기 위해서 차량의 위치 정보를 요구하는 환경에서 차량의 위치를 예측해 미리 알 수 있다면 높은 품질의 서비스를 만드는 것에 도움이 된다. 차량은 도시 환경에서 비교적 느린 속도를 갖는다는 특징이 있고 차량의 위치를 표시하는 방법도 여러 가지다. 본 논문은 Long Short-Term Memory(LSTM)을 사용해 차량의 이동 경로를 예측하는 과정에서 이동 속도와 위치 표현 방법이 미치는 영향을 분석하였다. 실험 결과 차량의 속도가 증가할수록, 차량의 이동 표현 방법이 세밀할수록 차량 이동 경로 예측이 어렵다는 것을 확인하였다.