• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1999.07a
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• pp.177-182
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• 1999

시설농업의 정치식 자동화장치들을 비롯하여 노지 재배를 위한 자율주행형 로봇에 이르기까지 무인화를 위한 노력이 농업의 전반에 확대되고 있으며 원격제어와 무선통신은 이를 실현하기 위한 중요한 기술수단으로 인식되고 있다. 일반적인 무선제어 장치의 발전과정을 보면 보다 많은 제어채널에 대한 정보전송, 확실하고 오류 없는 신호의 전송을 위한 전파방해 대책, 소형 경량화라는 3가지의 기술적 실현과정으로 집약할 수 있다. (중략)

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.3
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• pp.220-227
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• 2014

This paper presents about multi-rate sensors' synchronization and filter fusion via a sigmoid function of the Kalman filter. To synchronize multi-rate sensors, the estimation states of the Kalman filter is modified. A specific matrix that makes the filter choose sensor values only updated is multiplied to measurement matrix. For the filter that has weak points on some criteria, filter fusion is suggested by using sigmoid function. Modified kalman filter is tested with practical case. A sigmoid function was designed for the test and the performance of the modified function is estimated with respect to conventional Kalman filter. Unscented Kalman filter is used to the base filter of the suggested filter because of its stability.

• Journal of Advanced Navigation Technology
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• v.23 no.6
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• pp.542-547
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• 2019

Autonomous train is investigated to increase the capacity of railroad, and the reliability of wireless communication plays a critical role in terms of decreasing the inter-train distance. In this paper, we propose a transmission scheme for autonomous train communication in highly congested environment. The proposed scheme, namely distributed uplink orthogonal frequency division multiple access (OFDMA) random access (UORA), applies the triggered uplink access (TUA) and the UORA, introduced in the sixth generation WLAN standard, IEEE 802.11ax, for communication devices on vehicle and platform in a distributed manner. The simulation results show that the proposed scheme efficiently improves the packet transmission success rate in highly congested channel conditions compared to the conventional enhanced distributed channel access (EDCA) transmission scheme.

• Journal of Auto-vehicle Safety Association
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• v.13 no.4
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• pp.106-113
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• 2021

In this study, The behavior of an autonomous vehicle in an intersection accident situation is predicted. Based on a representative intersection accident situation from actual intersection accident database, simulation was performed by applying the automatic emergency braking algorithm used in the autonomous driving system. Accident reconstruction was performed based on the accident report of the representative accident situation. After applying the autonomous driving system to the accident-related vehicle, the tendency of intersection accidents that may occur in autonomous vehicles was identified and analyzed.

• Proceedings of the Korea Information Processing Society Conference
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• 2023.11a
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• pp.1119-1120
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• 2023

본 논문에서는 LiDAR 만을 이용한 자율주차 시스템을 제안한다. 목표하는 주차공간 양측에 위치한 차량을 감지하여 주차공간의 앞까지 이동한 후 조향장치를 제어하여 주차를 수행하는 알고리즘을 제시하였다. 또한 2023년도 제1회 성균관대학교 자율주행 SW 경진대회를 수행함으로써 해당 알고리즘의 유효성을 검증하였다.

• Journal of Digital Convergence
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• v.13 no.1
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• pp.297-304
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• 2015

Recently, the demand for a PRT(Personal Rapid Transit) system based on autonomous navigation is increasing. Accordingly, the applicability investigations of the PRT system on rail tracks or roadways have been widely studied. In the case of unmanned vehicle operations without physical guideways on roadways, to monitor the position of the vehicle in real time is very important for stable, robust and reliable guidance of an autonomous vehicle. The Global Positioning System (GPS) has been commercially used for vehicle positioning. However, it cannot be applied in environments as tunnels or interiors of buildings. The PRT navigation system based on magnetic markers reference sensing that can overcome these environmental restrictions and the vehicle dynamics model for its H/W configuration are presented in this study. In addition, the design of a control S/W dedicated for unmanned operation of a PRT vehicle and its prototype implementation for experimental validation on a pilot network were successfully achieved.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.1-9
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• 2016

Train control systems have changed from wayside electricity-centric to onboard communications-centric. The latest train control system, the CBTC system, has high efficiency for interval control based on two-way radio communications between the onboard and wayside systems. However, since the wayside system is the center of control, the number of input trains to allow a wayside system is limited, and due to the cyclic-path control flows between onboard and wayside systems, headway improvement is limited. In this paper, we propose a train interval-control and train-centric distributed interlocking algorithm for an autonomous train-driving control system. Because an autonomous train-driving control system performs interval and branch control onboard, both tracks and switches are shared resources as well as semaphore elements. The proposed autonomous train-driving control performs train interval control via direct communication between trains or between trains and track-side apparatus, instead of relying on control commands from ground control systems. The proposed interlocking algorithm newly defines the semaphore scheme using a unique key for the shared resource, and a switch that is not accessed at the same time by the interlocking system within each train. The simulated results show the proposed autonomous train-driving control system improves interval control performance, and safe train control is possible with a simplified interlocking algorithm by comparing the proposed train-centric distributed interlocking algorithm and various types of interlock logic performed in existing interlocking systems.

• The Journal of the Korea Contents Association
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• v.19 no.11
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• pp.474-481
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• 2019

Korea entered the aged society in 2018 with the elderly population accounting for 14.4% of the total population, and it is expected to enter the super-aged society in 2026. In particular, it is predicted that by 2050, the elderly population will be 38% of the total population, making it one of the countries with the highest number of elderly people in the world. The increase in the elderly population is naturally leading to an increase in the number of traffic accidents among elderly drivers, in 2017, there were 26,713 elderly driver accidents over 65 years of age, with 848 people dying and 38,627 injured. Compared with 2011, the number of accidents and injuries has doubled and the number of deaths has increased 1.4 times. This study determined that the main factors of the increase in traffic accidents were the characteristics of elderly drivers, such as a decrease in visual/hearing ability, cognitive and information processing ability, and muscle strength. Therefore, it raised the necessity of autonomous vehicle(level 2) for elderly driver who can minimize the burden of driving and aimed to study the function of autonomous vehicle for elderly driver who is not familiar with new technology. Based on this, four functions of autonomous vehicles for elderly drivers were derived, such as providing clear information according to the road environment, considering physical characteristics of drivers, simplifying interface, and reinforcing in-vehicle safety devices.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2022.11a
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• pp.183-186
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• 2022

최근 인공지능 기반 객체 탐지 기술이 발전함에 따라 영상 감시, 얼굴 인식, 로봇 제어, IoT, 자율주행, 제조업, 보안 등 다양한 분야에 활용되고 있다. 이에 본 논문은 발전된 객체 탐지 알고리즘을 이용하여 비전문가에겐 생소한 컴퓨터나 전기 장치 등의 '단자(terminal)' 모양을 구별하는 방법을 제안한다. 이를 위해 객체 탐지 프로그램인 You Only Look Once (YOLO) 알고리즘을 이용하여 입력한 단자들의 모양을 검출하는 알고리즘을 구성하였다. 일상에서 쉽게 볼 수 있는 단자들의 이미지(VGA, DVI, HDMI, DP, USB-A, USB-C)를 라벨링하여 데이터셋을 구축하였고, YOLOv4와 YOLOv5 두 버전의 알고리즘을 사용하여 성능을 검증하였다. 실험 결과 mean Average Precision(mAP) 기준 최대 92.9%의 정확도를 얻을 수 있었다. 전기 장치에 따라 단자의 모양이 다양하고, 그 종류 또한 많기 때문에 본 연구가 방송 기술 등의 여러 분야에 응용될 것으로 기대된다.

• Proceedings of the Korea Information Processing Society Conference
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• 2021.11a
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• pp.276-279
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• 2021

캔 통신은 차량 내부의 전자장치 간 데이터 송수신 시에 사용되는 통신 방식이다. 차량 기술이 발전함에 따라 내부에 탑재되는 전자장치가 늘어나고 있고 이는 해킹의 위험성이 높아지고 있음을 의미한다. 이는 다가오는 4차 산업 혁명에서 자율주행 차량 기술의 치명적인 문제로 작용할 수 있다. 본 논문에서는 CAN Bus 통신에서의 위협 대응 방안과 안정성 향상에 대한 연구들의 동향을 살펴본다.