• IEMEK Journal of Embedded Systems and Applications
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• v.19 no.4
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• pp.175-184
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• 2024

This research addresses the problem of robot localization in corridor environments using LiDAR (Light Detection and Ranging). Due to the rank deficiency problem in scan matching with LiDAR alone, the accuracy of robot localization may degenerate seriously. This paper proposes an adaptive sampling-based particle filtering method using depth sensors to overcome the rank deficiency problem. The increase in the sample size in particle filters can be considered to solve the problem. But, it may cause much computation cost. In the proposed method, the sample size of the particle set in the proposed method is adjusted adaptively to the confidence of depth sensor data. The performance of the proposed method was test by real experiments in various environments. The experimental results showed that the proposed method was capable of reducing the estimation errors and more accurate than the conventional method.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.169-172
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• 1998

A 3D-ray tracing using triangular ray tubes for predicting propagation in indoor environments is presented. Employed ray tracing scheme needs no reception sphere often suffered from how to assign the correct radius as a touching ray on the receiver. To verify the developed codes path loss for a rectangular corridor has been computed, measured, and compared with those by image methods, all shows good agreement to each other. Discussions are made on the path loss fluctuations along the distance in a rectangular corridor having a conducting knife.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.461-471
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• 2004

The primary objective of this paper is to investigate the corridor of Eurasia High-Speed Railway Network from the governmental view of the Republic of Korea, whose High-Speed Train has been recently operated. The country is also expected to figure out the changes of Eurasia infrastructure system under the assumption that Trans-Korean Railway is connected to the Continent. As a result of research, the corridor connecting the TKR to TSR seems to be more attractive to the Republic of Korea than that of the TKR-TCR under the current economic and operational environments. However, even in a case, the railway linkage through the TSR between Europe and Asia should remain a supplementary means of the sea transportation route. Lastly, TSR may need a program of structural reforms, in order to continuously provide preferable services like the Pan-European Transport Network (PETN) which is currently initiated by the European Union, such as to improve outdated infrastructure (railway, bridges, signal systems, etc.), to simplify and to standardize the process of custom clearance and internal tariffs, and ultimately to construct a uniform management system for the corridor linking the TKR to TSR.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.758-761
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• 2003

This paper introduces a method that can detect obstacles and corridor environments from the images captured by a CCD camera in an automobile or mobile robot is proposed. Processing the input dynamic images in real time requires high performance hardware as well as efficient software. In order to relieve these requirements for detecting the useful information from the images in real time, a "Moving Window" scheme is proposed. Therefore, detecting the useful information, it becomes possible to search the obstacles within the driving corridor of an automobile or mobile robot. The feasibility of the proposed algorithm is demonstrated through the simulated experiments of the corridor driving.

• Journal of Korea Society of Industrial Information Systems
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• v.26 no.4
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• pp.11-18
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• 2021

We propose a method that combines learning in a virtual environment and a real environment for indoor autonomous driving through reinforcement learning. In case of learning only in the real environment, it takes about 80 hours, but in case of learning in both the real and virtual environments, it takes 40 hours. There is an advantage in that it is possible to obtain optimized parameters through various experiments through fast learning while learning in a virtual environment and a real environment in parallel. After configuring a virtual environment using indoor hallway images, prior learning was carried out on the desktop, and learning in the real environment was conducted by connecting various sensors based on Jetson Xavier. In addition, in order to solve the accuracy problem according to the repeated texture of the indoor corridor environment, it was possible to determine the corridor wall object and increase the accuracy by learning the feature point detection that emphasizes the lower line of the corridor wall. As the learning progresses, the experimental vehicle drives based on the center of the corridor in an indoor corridor environment and moves through an average of 70 steering commands.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.1 no.1
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• pp.35-39
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• 2008

In this paper, we have developed a propagation loss prediction software with GUI (Graphic User Interface) functions, based on the geometrical ray optics model, which can predict radio parameters for the deployment of wireless indoor network. The program has two numerical modules consisted with electrical image and ray launching methods to implement UTD theory. The simulated results are compared with reported data measured in the foreign building environments for office and '一' type corridor, and measured and simulated results for the propagation loss agree with each other quite well. Simulation results for '一' type corridor and 'T' type corridor propagation environment are shown for reference.

• Journal of Biomedical Engineering Research
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• v.15 no.1
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• pp.27-34
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• 1994

In this paper. a way to analysis a corridor scene for a vehicle's automatic locomotion is presented In general, it's necessary for a vision system of vehicles to identify its positions in given environments. The suggested algorithm is to decide base lines of a corridor image using the vanishing point finding. Feature points are extracted on the base line using a base line extraction tree. This algorithm is suitable for a motorized wheelchair's self locomotion in a building.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1544-1549
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• 2004

A new collision avoidance algorithm is presented for two mobile robots in narrow corridor environments. When two robots meet each other in a narrow corridor, one should yield the way to the other robot. To solve the problem arising in this situation, they exchange their path to get information about crossing-points to check avoidance conditions, which are necessary for choosing the robot to yield. The conditions are summarized as follows. 1) If one robot blocks the path to the closest crossing-point in front of the other robot. 2) If the closest crossing-point of each robot is the same point. 3) Which robot is closer to the closest crossing-point. In this paper, we propose a path planning algorithm for the robot which yield the way. Simulation results are presented to verify the feasibility of the proposed collision avoidance algorithm.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.34S no.11
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• pp.1-8
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• 1997

A prediction model is proposed to describe the path loss in propagation environment of indoor microcell. This model includes the lineal corridor for line--of-sight(LOS) and T-shaped corridor for non-line-of-sight(NLOS). In computation of receiving power the ray tracing technique based on image method is utilized and also reflected waves bounced on the walls and ceilings are considered. To check validity of the computed resuls cross checks between the predicted and measured are being made, which shows a close agreement for LOS case whereas somewhat disagreement for NLOS case. UTD technique is incorporated with propagation path determination algorithm in the treatment of NLOS case.

• Korean Institute of Interior Design Journal
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• v.15 no.5 s.58
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• pp.221-229
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• 2006

The purpose of this study is to analyze the characteristics of healing environments of the wards in women's hospitals. A evaluation checklist of the healing environment was applied to seven women's hospitals that have constructed or remodeled since 2000. The findings indicate that the comfort was well considered in most spaces, while the privacy and the nature-friendliness were insufficient. The lacks of balconies, terraces, landscapes, and water spaces for the nature-friendliness were also problematic. Among the patients' room, corridor, and patients' lounge, the lounge was the most negative in terms of healing environments. In order to improve the patients' privacy, soundproofing materials and buffer zones in the lounge should be considered. The future study needs to develop advanced survey and interview methodologies in order to support the relevant results.