• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.8
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• pp.1503-1517
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• 1994

Intelligent Motion Planning System(IMPS) is presented for a robot to achieve an efficient path toward the given target point in two dimensional unknown environment is constructed with unrestricted obstacle shapes. IMPS consists of three components for making intelligent motion. These components are real-time motion planning algorithm based on a discontinous boundary method, fuzzy neural network decision system for heuristic knowledge representation, and world modeling with forgetting and reinforcing memory cells. First of all, in real-time motion planning algorithm, the behavior-based architectural method is used to generate subgoal. A behavior generates a subgoal independently by using the method of discontinuous boundary in sensed area. The discontinuous boundary method is a new proposed fast obstacle avoidance algorithm. The second component is fuzzy neural network decision system for accomplishing the subgoal. The heuristic rules are imbedded on the fuzzy neural network to make an intelligent decision. The last one is a forgetting, reinforcing memory technique for the construction of external world map. The activation values of all activated memory cells in grid space are decreased monotonically and after all they are burned out. Therefore, after sufficient journey, robot can have a stationary world map even if the dynaic obstacles exist. Using the IMPS, several simulations show the efficient achievement of target point in unknown enviroment with obstcles of various shapes.

• Proceedings of the Korean Information Science Society Conference
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• 1998.10c
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• pp.348-350
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• 1998

시뮬레이션 환경이나 실제 환경에서 이동 로봇의 제어에 관한 많은 연구가 진행되어 왔다. 이러한 연구 중에서 이동 로봇이 장애물을 피한다거나, 움직이는 물체를 잡는 등의 행동을 유전자 알고리즘 등의 진화 알고리즘으로 만들어내는 연구가 최근 활발하다. 이전의 연구에서는 셀룰라 오토마타 상에서 진화의 방법으로 신경망을 성장시키는 모델을 제시하고, 그 유용성을 입증하고자 이동로봇의 제어에 적용하여 나름대로 만족할 만한 결과를 얻을 수 있었다. 그러나 이러한 진화의 방법은 환경에 제한된 제어기를 만들어 내는 문제점이 있어 본 논문에서는 점증적인 진화의 방법을 이용하여 좀더 다양한 환경에 적응할 수 있는 제어기를 만들어 내고자 한다. 점증적 방법은 초기에 간단한 행동으로 해결할 수 있는 환경에 맞도록 제어기를 진화시킨 다음, 점차 복잡한 행동이 요구되는 환경에서 제어기를 점증적으로 진화시킨다. 실험 결과, 점증적 진화의 방법이 좀더 효율적으로 로봇을 진화시키고 환경의 변화에 보다 강한 것을 알 수 있었다.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.30 no.3
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• pp.59-92
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• 2019

The purpose of the study is to develop the indicator and scale for evaluating the service environments of archives and to assess the physical service environments of National Archives of Korea (NAK), and then to suggest the alternatives to improve the current service environments on the basis of the results of evaluation. To achieve the purpose, the study designed three research phases: first, to develop the indicator and scale to measure the current service environments by merging universal design indicators and various standards of NAK for establishing facilities and environments on the basis of the barrier-free authentication indicators; second, to evaluate the current service environments of NAK with the newly developed scale; finally to suggest alternatives to improve the current environments on the basis of the evaluation findings. The study found that current service environments of NAK have critical limits on the areas and facilities to provide direct archival information services to users such as reference service desks, showrooms, education rooms, seminar rooms, etc. On the basis of the results, the study suggested the alternatives and further studies for making barrier-free service environments of archives.

• Journal of the Korean Institute of Intelligent Systems
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• v.19 no.4
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• pp.451-456
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• 2009

In this paper, a virtual force is generated and fed back to the operator to make the teleoperation more reliable, which reflects the relationship between a slave robot and an uncertain remote environment as a form of an impedance. In general, for the teleoperation, the teleoperated mobile robot takes pictures of the remote environment and sends the visual information back to the operator over the Internet. Because of the limitations of communication bandwidth and narrow view-angles of camera, it is not possible to watch certain regions, for examples, the shadow and curved areas. To overcome this problem, a virtual force is generated according to both the distance between the obstacle and the robot and the approaching velocity of the obstacle w.r.t the collision vector based on the ultrasonic sensor data. This virtual force is transferred back to the master (two degrees of freedom joystick) over the Internet to enable a human operator to estimate the position of obstacle at the remote site. By holding this master, in spite of limited visual information, the operator can feel the spatial sense against the remote environment. It is demonstrated by experiments that this collision vector based haptic reflection improves the performance of teleoperated mobile robot significantly.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2008.04a
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• pp.46-49
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• 2008

본 논문은 이동 로봇의 이동 및 거리 센싱의 불확실성을 고려한 시뮬레이터 개발에 대해 소개한다. 이동 로봇은 구동기, 바닥의 불안정성, 바퀴 및 구동 기구의 불확실성, 그리고 기타 구조적으로 어려운 다양한 원인으로 동작 명령과 차이가 있게 이동한다. 또한 이동 로봇에 장착된 각종 센서는 센서 자체의 불안정성, 주변 환경의 불안정성등에 의하여 정확한 측정값을 출력하지 못한다. 이러한 이동 및 센서의 불안정성은 로봇의 자율 주행 알고리즘의 구현이 가장 큰 장애물이 되고 있다. 예측하기 어려운 불안정성을 고려하지 않은 알고리즘은 실제 환경에서 필연적으로 동작에 실패하여 크고 작은 사고를 일으킨다. 따라서 알고리즘의 검증을 위해 시뮬레이터가 각종 불확실성을 포함하여 로봇 동작이 실제에 유사하도록 하여야 한다. 본 연구에서는 이동 로봇의 이동과 센싱에 불확실성을 포함하도록한 시뮬레이터를 개발하였다. 다양한 센서들 중 이동 로봇의 위치 추정, 장애물 인식, 지도 작성등에 가장 기본적으로 사용되는 영역 센서를 대상으로 불확실성을 구현하였다. 개발된 시뮬레이터를 사용하여 알고리즘을 검증하는 경우와 불확실성을 고려하지 않은 시뮬레이터를 사용하여 알고리즘을 검증하는 경우를 비교하여, 제안된 시뮬레이터의 성능을 검증하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2016.04a
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• pp.975-976
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• 2016

Beacon 기술은 배터리 소모가 적고 간편하게 장치와의 거리를 측정할 수 있어 여러 분야에 사용되고 있지만 장애물의 간섭에 약하다는 문제점이 있다. 따라서 본 논문에서는 이러한 문제를 개선하고자 간섭에 강한 WiFi 환경과 오픈소스 Frameware인 OpenWrt를 이용해 Raspberry pi를 AP화 시켜 Beacon 장치를 탐지하여 수신한 데이터를 사설 네트워크 내 장치들에게 안정적으로 전달할 수 있는 장치를 제안한다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.13 no.2
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• pp.32-38
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• 1999

An autonomous mobile vehicle for transport system must plan optimal path in work envimnrent without human supervision and obstacle collision. This is to reach a destination without getting lost. In this paper, a genetic algorithm for globaI and local path planning and collision avoidance is proposed. The genetic algorithm searches for a path in the entire and continuous free space and unifies global path planning and local path planning. The sinmulation shows the proposed method is an efficient and effective method when compared with the traditional collision avoidance algorithms.rithms.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2007.11a
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• pp.328-332
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• 2007

본연구에서는 센서의 융합을 통하여 환경을 인식하며, 주변환경에 대한 지식을 갱신, 학습할수 있는 방법론을 연구하며, 동적인 장애물의 감지및 움직임 예측에 기반한 지능적 회피 알고리즘과 AHP를 이용한 Navigation Strategy수정과 이동 로봇 스스로 최적의 결과를 낼수 있게 개선 시키는 알고리즘을 구현한다. 그와 더불어 AHP를 이용하여 Navigation Performance를 최대로 높일 수 있는 방향을로 진화시키는 알고리즘을 구현한다. 또한 부여된 임무수행을 위한 목표물 추적을 위한 비전 시스템에서의 대상체 추출및 인식 알고리즘을 개발하며 인간뇌의 환경인식 체계와 유사한 방식의 Map building기법을 연구한다.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.8 no.3
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• pp.945-953
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• 2018

In this paper, we use 3-D LIDAR for obstacle detection and avoidance maneuver for autonomous unmanned operation. It is aimed to avoid obstacle avoidance in unmanned water under marine condition using only single sensor. 3D lidar uses Quanergy's M8 sensor to collect surrounding obstacle data and includes layer information and intensity information in obstacle information. The collected data is converted into a three-dimensional Cartesian coordinate system, which is then mapped to a two-dimensional coordinate system. The data including the obstacle information converted into the two-dimensional coordinate system includes noise data on the water surface. So, basically, the noise data generated regularly is defined by defining a hypothetical region of interest based on the assumption of unmanned water. The noise data generated thereafter are set to a threshold value in the histogram data calculated by the Vector Field Histogram, And the noise data is removed in proportion to the amount of noise. Using the removed data, the relative object was searched according to the unmanned averaging motion, and the density map of the data was made while keeping one cell on the virtual grid map. A polar histogram was generated for the generated obstacle map, and the avoidance direction was selected using the boundary value.

• Spatial Information Research
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• v.22 no.1
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• pp.75-84
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• 2014

Power lines are one of the main obstacles causing an aircraft crash and thus their realtime detection is significantly important during flight. To avoid such flight obstacles, the use of LIDAR has been recently increasing thanks to its advantages that it is less sensitive to weather conditions and can operate in day and night. In this study, we suggest a fast method to detect power lines from LIDAR data for flight obstacle avoidance. The proposed method first extracts non-ground points by eliminating the points reflected from ground surfaces using a filtering process. Second, we calculate the eigenvalues for the covariance matrix from the coordinates of the generated non-ground points and obtain the ratio of eigenvalues. Based on the ratio of eigenvalues, we can classify the points on a linear structure. Finally, among them, we select the points forming horizontally long straight as power-line points. To verify the algorithm, we used both real and simulated data as the input data. From the experimental results, it is shown that the average detection rate and time are 80% and 0.2 second, respectively. If we would improve the method based on the experiment results from the various flight scenario, it will be effectively utilized for a flight obstacle avoidance system.