• Title/Summary/Keyword: Safe

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Amber Information Design to Keep Safety-Driving Under Road Structure at Local-Scale Geographic (국지지역 도로 기반 시설에서 안전운전을 위한 경보 정보 설계)

  • Park, Jung-Chan;Hong, Gyu- Jang
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.58 no.1
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    • pp.48-55
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    • 2009
  • In order to keep safe driving conditions under road networks, there are several formations such as road structure, road surface condition, traffic occupancy and supplement of an accurate information of traffic status ahead To support safe-driving on each road formation, each formation is supplied with various information to help the driver. However, in some cases like rapid status change at local-scale geography, traffic information systems often displays insufficient information because of the lack of information correlation. In order to accurately aware the driver, all road formation must be in sync. It is important to supply accurate information to the driver because this information directly impacts the drivers on the road. This paper discusses the amber information to keep the least safety driving over road formations including tunnels and bridges. This paper also will propose the informations for safe-driving conditions, information linkage on the road and rule-base safety information, as ITS technology, being displayed for all drivers under the worst weather conditions.

Path Planning based on Ray-casting in Indoor Environments for Safe Navigation of a Mobile Robot (이동로봇의 안전한 주행을 위한 광선투사법 기반의 실내 경로계획)

  • Kim, Jong-Won;Song, Jae-Bok
    • The Journal of Korea Robotics Society
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    • v.5 no.4
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    • pp.302-308
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    • 2010
  • A gradient method can provide a global optimal path in indoor environments. However, the optimal path can be often generated in narrow areas despite a sufficient wide area which lead to safe navigation. This paper presents a novel approach to path planning for safe navigation of a mobile robot. The proposed algorithm extracts empty regions using a ray-casting method and then generates temporary waypoints in wider regions in order to reach the goal fast and safely. The experimental results show that the proposed method can generate paths in the wide regions in most cases and the robot can reach the goal safely at high speeds.

Polyhydroxyamic Acid from 3,3′ - Dihydroxybenzidine and Pyromellitic Dianhydride as a Fire-safe Polymer

  • Park, Seung Koo;Farris, Richard J.;Kantor, Simon W.
    • Fibers and Polymers
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    • v.5 no.2
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    • pp.83-88
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    • 2004
  • In order to assess the potential of the hydroxy-containing polyamic acid (PHAA) synthesized from 3,3'-dihydroxy benzidine and pyromellitic dianhydride for a fire-safe polymer, the cyclization pathway of PHAA has been investigated using a model compound prepared from 2-aminophenol and phthalic anhydride. The reaction was monitored. by $^1{H-nuclear}$ magnetic resonance. N-(2-hydroxyphenyl) phthalamic acid is converted to N-(2-hydroxyphenyl) phthalimide at ca. 175$^{\circ}C$, showing endothermic reaction. The imide structure is rearranged to the benzoxazole structure over ca. $400^{\circ}C$. These results are similar with that of PHAA. According to pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) data, water and carbon dioxide are released during the cyclization and rearrangement reaction. One DMAc molecule is complexed with one carboxyl acid group in PHAA, which accelerates the imidization process to release more easily the flame retardant, water.

A Study on the Minimum Safe Distance between Two Vessels in Confined Waters

  • Lee, Chun-Gi;Mun, Seong-Bae;Jeong, Tae-Gwon;Jeong, Yeon-Cheol;Gong, Gil-Yeong;Lee, Jun-Ho
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2013.10a
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    • pp.56-57
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    • 2013
  • This paper is mainly concerned with the interaction effects between two vessels and sidewall with a mound. Experimental study on hydrodynamic forces between ship and sidewall with a mound was already shown in the previous paper, measured by varying the distances between ship and sidewall. The ship maneuvering simulation was conducted to find out the minimum safe distance between vessels, which is needed to avoid sea accident in confined waters.

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A Study on Safety Assessment and Design of the Safe Task in Automated Man-Machine System (자동생산체계에서 인간-기계 시스템의 안전도측정과 안전작업설계에 관한 연구)

  • 오영진
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.13 no.22
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    • pp.71-78
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    • 1990
  • Some problems to assess the safety of automated man-machine system are studied in many ways. The difficulty occurred in this system is the vagueness of human behavior. Fuzzy set theory is used to assess the human behavior in safety analysis. The unsafe behavior listed top 10 in accident statistics would be explained as the factors of human vagueness. Three cases are considered, which consist of man-machine system as man-man, man-machine, machine-machine types. For the design of safe task, using characteristics of work performance, each motion cycle time is required to know the rate of learning. Approach of human behavior to the standard motion means more safe motion. It is important to design the works as to minimize the time performance to the standard motion's, which utilize the control of risk potential with easy. In that process, use of fuzzy set theory is appropriate to analyze the human behavior to identify its vagueness.

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A Study on the Minimum Safe Distance between Two Vessels in Confined Waters

  • Lee, Chun-Ki;Moon, Serng-Bae
    • Journal of Navigation and Port Research
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    • v.38 no.6
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    • pp.561-565
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    • 2014
  • This paper is mainly concerned with the interaction effects between two vessels and sidewall with a mound. Experimental study on hydrodynamic forces between ship and sidewall with a mound was already shown in the previous paper, measured by varying the distances between ship and sidewall. The ship maneuvering simulation was conducted to find out the minimum safe distance between vessels, which is needed to avoid sea accident in confined waters. From the inspection of this investigation, it indicates the following result. When and if one vessel passes the other vessel through the proximity of sidewall with a mound, the spacing between two vessels is needed for the velocity ratio of 1.2, compared to the case of 1.5. Also, for the case of ship-size estimation, the ship maneuvering motion is more affected by interaction effects for the overtaken small vessel, compared to the overtaking large vessel.

Hybrid Controller Design for a Safe Lane Change Maneuver in Automated Highway Systems (차량 자동주행 시스템의 안전한 차선변경을 위한 하이브리드 제어기 설계)

  • 최재원;최재원;김영호
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.17-17
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    • 2000
  • In this paper, we design a hybrid controller for a safe lane change maneuver in automated highway systems(AHS). The proposed hybrid controller consists of a supervisor which controls the behaviors of discrete-event dynamic systems, and a regulator which controls the operations of continuous-variable dynamic systems. The supervisor determines whether the system starts a maneuver or not, via a condition for a safety, and gives orders to the regulator for performing the maneuvers. And the regulator tracks the planned path generated in the supervisor. The conditions for a safe lane change maneuver are proposed using the velocity, the acceleration, and geometrical relationship of vehicles.

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Real-time Dangerous Driving Behavior Analysis Utilizing the Digital Tachograph and Smartphone

  • Kang, Joon-Gyu;Kim, Yoo-Won;Jun, Moon-Seog
    • Journal of the Korea Society of Computer and Information
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    • v.20 no.12
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    • pp.37-44
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    • 2015
  • In this paper, we propose the assistance method to enable safe driving through analysis of dangerous driving behavior using real-time alarm by vehicle speed, azimuth data and smartphone. For this method, smartphone is receiving driving data from digital tachograph using communication. Safe driving habit is a very important issue to commercial vehicle because that driver's long time driving than other vehicle type driver. Existing methods are very inefficient to improve immediately dangerous driving habits during driving because proceed driving behavior analysis after the vehicle operation. We propose the new safe driving assistance method that can prevent traffic accidents by real-time and improve the driver's wrong driving habits through real-time dangerous driving behavior analysis and notification the result to the driver. We have confirmed that the method in this paper will help to improve driving habits and can be applied through the proposed method implementation and simulation experiment.

A Study on Principles for Safe Driving of the Urban Railway Train (도시철도 열차의 안전 운전원칙에 관한 연구)

  • Jeon, Young-Seok;Ahn, Seung-Ho;Chung, Kwang-Woo;Kim, Jae-Moon;Kim, Chul-Su;Chung, Jong-Duk;Jeong, Rag-Gyo
    • Proceedings of the KSR Conference
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    • 2009.05a
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    • pp.628-635
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    • 2009
  • To assure the safety of urban railway train, it is necessary to observe the specified driving principles under an essential condition during running on tracks. These principles arises from a great deal of experience for a long time and include safe distance between trains, the railway signaling, block system, regular block of the highest priority and driving prohibition of simple railway vehicle in the main track, etc. Therefore, it is important to apply these principles to domestic urban railway driving regulations and railway vehicle driving regulations. However, domestic urban railway administrator established his own operation rules within the regulation. In this study, domestic urban railway administration's own rules are examined and the appropriate driving regulation on the safe driving principles is proposed.

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Planning of Safe and Efficient Local Path based on Path Prediction Using a RGB-D Sensor (RGB-D센서 기반의 경로 예측을 적용한 안전하고 효율적인 지역경로 계획)

  • Moon, Ji-Young;Chae, Hee-Won;Song, Jae-Bok
    • The Journal of Korea Robotics Society
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    • v.13 no.2
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    • pp.121-128
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    • 2018
  • Obstacle avoidance is one of the most important parts of autonomous mobile robot. In this study, we proposed safe and efficient local path planning of robot for obstacle avoidance. The proposed method detects and tracks obstacles using the 3D depth information of an RGB-D sensor for path prediction. Based on the tracked information of obstacles, the paths of the obstacles are predicted with probability circle-based spatial search (PCSS) method and Gaussian modeling is performed to reduce uncertainty and to create the cost function of caution. The possibility of collision with the robot is considered through the predicted path of the obstacles, and a local path is generated. This enables safe and efficient navigation of the robot. The results in various experiments show that the proposed method enables robots to navigate safely and effectively.