• 제목/요약/키워드: risk of collision

검색결과 370건 처리시간 0.029초

Agricultural Accidents in Farm Workers (일 지역 농업인의 농작업 재해사고)

  • Kim, Hann-Sook;Choi, Yeon-Hee
    • Research in Community and Public Health Nursing
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    • 제18권4호
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    • pp.643-650
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    • 2007
  • Purpose: This study was to obtain information regarding to agricultural accidents in farm workers in the Kyungpook area. Methods: A questionnaire survey was carried out for 528 workers from the 1st to 31st of March, 2007. Frequency, percentage, mean and chi-square test with the SPSS program were used to analyze the data. Results: The causes of agricultural accidents include falling(29.0%), overseeing(18.9%), traffic accident(17.4%), putting between machinery(11.7%), crashing(5.3%), fire (0.6%) in the order of frequency. Injuries from agricultural accidents include fracture(44.7%) cerebral bleeding (10.4%), amputation(7.0%), airway obstruction (2.3%) burn(1.9%), drug addiction(1.9%) in the order of frequency. The largest proportion of the subjects of hospital treatment were in their 50s and belonged to the group of high-level economic state. Agricultural machinery collision was the most frequent cause among the subjects of hospital treatment. Conclusion: These results suggest that carelessness can be a potential risk factor for agricultural accidents in farm workers. These findings may give useful information for developing agricultural accident prevention programs for farm workers.

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A Study on the Improvement of Marine Traffic System in the Ulsan Approaching Waters (울산항 접근수역의 항로지정에 관한 연구)

  • Jeong, Jae-Yong;Yoon, Dae-Gwun;Kim, Cheol-Seung
    • Journal of the Korean Society of Marine Environment & Safety
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    • 제16권2호
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    • pp.209-214
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    • 2010
  • This study examined environmental condition, marine accidental data, marine traffic capacity and traffic flow, and fisheries zone status near Ulsan approaching water area. A questionnaire survey of marine traffic system was conducted on experts and users, and new plan was proposed. On the basis of the responses of experts and users to questionnaire, the essential factor of navigation danger and the essential factor of collision risk as well as the improvement plans were proposed. More efficient navigational fairway was set up through this study.

A Study on the Analysis of TEB Local Planner Parameters to Improve the Target Reach Time of Autonomous Mobile Robot (자율주행 이동로봇의 목표 도달 시간을 개선하기 위한 TEB Local Planner 파라미터의 분석에 관한 연구)

  • Roh, Hyeong-Seok;Jung, Ui;Han, Jung-Min;Jeon, Jung-Hyeon;Jeon, Ho-Nam
    • Journal of the Korean Society of Industry Convergence
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    • 제25권5호
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    • pp.853-859
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    • 2022
  • In this study, we analyzed the instantaneous trajectory generation capability and target arrival rate of a mobile robot by changing the parameter of the TEB (Timed Elastic Band) Local Planner among local planners that affect the instantaneous obstacle avoidance ability of the mobile robot using ROS (Robot Operating System) simulation and real experience. As a result, we can expect a decrease in the target arrival time of the mobile robot through a decrease in the parameter values of the TEB Local Planner's min_obstacle_dist, inflation_dist, and penalty_epsilon. However, if this parameter is reduced too much, the risk of obstacle collision of the moving robot is increases, so it is important to combine the appropriate values to construct the parameter.

Legal Issues on the Diving Apparatus Fishery: The case of contract responsibility and accountability at the time of ship collision (잠수기 어업과 관련한 법률상의 쟁점 -약정책임과 선박충돌시의 법정책임을 중심으로-)

  • Heo, Gyeom;Shin, Hyeon-Ok;Lim, Seok-Won
    • Journal of Fisheries and Marine Sciences Education
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    • 제26권3호
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    • pp.647-655
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    • 2014
  • In this research, unlike other fishing, the diving apparatus fishery is that the diver is engaged in fishing for profits. Because it is unique fishery, conflicts can be occurred in members. So, the purpose of this research is to define the contractual relationship between the parties of the diving apparatus fishery. For example, the relationship between the owner and diver and the owner and fishing ship crew. In addition, civil liability of default on the obligation was reviewed. Also, because the trouble was occurred by illegal fishing, criminal liability of ship crash caused by illegal diving apparatus fishery was considered. As a result, It is important to notifying the necessity of some method for the status of diver and fishing ship crew in diving apparatus fishery. moreover, It is need to educate the risk of illegal fishery for the parties of diving apparatus fishery.

Image-based ship detection using deep learning

  • Lee, Sung-Jun;Roh, Myung-Il;Oh, Min-Jae
    • Ocean Systems Engineering
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    • 제10권4호
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    • pp.415-434
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    • 2020
  • Detecting objects is important for the safe operation of ships, and enables collision avoidance, risk detection, and autonomous sailing. This study proposes a ship detection method from images and videos taken at sea using one of the state-of-the-art deep neural network-based object detection algorithms. A deep learning model is trained using a public maritime dataset, and results show it can detect all types of floating objects and classify them into ten specific classes that include a ship, speedboat, and buoy. The proposed deep learning model is compared to a universal trained model that detects and classifies objects into general classes, such as a person, dog, car, and boat, and results show that the proposed model outperforms the other in the detection of maritime objects. Different deep neural network structures are then compared to obtain the best detection performance. The proposed model also shows a real-time detection speed of approximately 30 frames per second. Hence, it is expected that the proposed model can be used to detect maritime objects and reduce risks while at sea.

Empirical Study of Smart Safety System to Increase Construction Disaster Prevention Effect - Centered on Construction Machinery (건설 재해 예방효과 증대를 위한 스마트 안전 시스템 실증연구 - 건설기계 중심)

  • Seung-Yong Choi
    • Journal of the Society of Disaster Information
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    • 제19권2호
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    • pp.421-431
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    • 2023
  • Purpose: The purpose of this study is to analyze the safety and disaster prevention effects of the Smart Safety System used to prevent safety accidents in construction machinery and demonstrate its safety. Method: Among construction machines, the behavioral patterns of workers according to the presence or absence of a smart safety system were analyzed for excavators with high risk and frequent accidents. Result: When the smart safety system was installed in the construction machine, the safety of workers from accidents caused by constriction and collision with the construction machine was secured. Conclusion: It is judged that the smart safety system installed in construction machinery can increase the effectiveness of disaster reduction and major disaster prevention related to construction machinery.

Station Collocation of Geostationary Spacecraft Via Direct Control of Relative Position (상대위치 직접 제어를 통한 정지궤도 위성의 Collocation에 관한 연구)

  • Lee, Jae-Gyu;No, Tae-Su
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • 제34권5호
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    • pp.56-64
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    • 2006
  • Station collocation of closely placed multiple GEO spacecraft is required to avoid the problem of collision risk, attitude sensor interference and/or occultation. This paper presents the method of obtaining the orbit correction scheme for collocating two GEO spacecraft within a small station-keeping box. The relative motion of each spacecraft with respect to the virtual geostationary satellite is precisely expressed in terms of power and trigonometry functions. This closed-form orbit propagator is used to define the constraint conditions which meet the requirements for the station collocation. Finally, the technique of constrained optimization is used to find the orbit maneuver sequence. Nonlinear simulations are performed and their results are compared with those of the classical method.

Local Path Planning for Mobile Robot Using Artificial Neural Network - Potential Field Algorithm (뉴럴 포텐셜 필드 알고리즘을 이용한 이동 로봇의 지역 경로계획)

  • Park, Jong-Hun;Huh, Uk-Youl
    • The Transactions of The Korean Institute of Electrical Engineers
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    • 제64권10호
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    • pp.1479-1485
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    • 2015
  • Robot's technology was very simple and repetitive in the past. Nowadays, robots are required to perform intelligent operation. So, path planning has been studied extensively to create a path from start position to the goal position. In this paper, potential field algorithm was used for path planning in dynamic environments. It is used for a path plan of mobile robot because it is elegant mathematical analysis and simplicity. However, there are some problems. The problems are collision risk, avoidance path, time attrition. In order to resolve path problems, we amalgamated potential field algorithm with the artificial neural network system. The input of the neural network system is set using relative velocity and location between the robot and the obstacle. The output of the neural network system is used for the weighting factor of the repulsive potential function. The potential field algorithm problem of mobile robot's path planning can be improved by using artificial neural network system. The suggested algorithm was verified by simulations in various dynamic environments.

Numerical Investigation of Large-capacity Wind Turbine Wake Impact on Drone system during Maintenance (수치해석 활용 대용량 풍력발전시스템 유지보수 시 타워 및 블레이드 후류에 따른 드론 블레이드 간섭 연구)

  • Jun-Young Lee;Hyun-Choi Jung;Jae-ho Jeong
    • Journal of Wind Energy
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    • 제14권3호
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    • pp.100-108
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    • 2023
  • The aim of this study is to develop guidelines for predicting interference between drones and wakes during non-destructive blade inspections in wind power systems. The wake generated by wind towers and blades can affect the stability of drone flights, necessitating the establishment of guidelines to ensure safe and efficient inspections. In order to predict the interference between drones and blades, environmental variables must be considered, including quantification of turbulence intensity in the wake generated by the tower and blades, as well as determining the appropriate distance between the drone and the tower/blades for flight stability. To achieve this, computational fluid dynamics (CFD) analysis was performed using cross-sectional geometries corresponding to the main wind turbine blade and tower span locations. Based on the CFD analysis results, a safe flight path for drones is proposed, which minimizes the risk of collision and interference with towers and blades during maintenance operations of wind power systems. Implementation of the proposed guidelines is expected to enhance the safety and efficiency of maintenance work.

Coupled foot-shoe-ground interaction model to assess landing impact transfer characteristics to ground condition

  • Kim, S.H.;Cho, J.R.;Choi, J.H.;Ryu, S.H.;Jeong, W.B.
    • Interaction and multiscale mechanics
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    • 제5권1호
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    • pp.75-90
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    • 2012
  • This paper investigates the effects of sports ground materials on the transfer characteristics of the landing impact force using a coupled foot-shoe-ground interaction model. The impact force resulting from the collision between the sports shoe and the ground is partially dissipated, but the remaining portion transfers to the human body via the lower extremity. However, since the landing impact force is strongly influenced by the sports ground material we consider four different sports grounds, asphalt, urethane, clay and wood. We use a fully coupled 3-D foot-shoe-ground interaction model and we construct the multi-layered composite ground models. Through the numerical simulation, the landing impact characteristics such as the ground reaction force (GRF), the acceleration transfer and the frequency response characteristics are investigated for four different sports grounds. It was found that the risk of injury, associated with the landing impact, was reduced as the ground material changes from asphalt to wood, from the fact that both the peak vertical acceleration and the central frequency monotonically decrease from asphalt to wood. As well, it was found that most of the impact acceleration and frequency was dissipated at the heel, then not much changed from the ankle to the knee.