• Title/Summary/Keyword: Operator safety

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SOME POWER UPRATE ISSUES IN NUCLEAR POWER PLANTS

  • Tipping, Philip
    • Nuclear Engineering and Technology
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    • v.40 no.4
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    • pp.251-254
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    • 2008
  • Issues and themes concerned with nuclear power plant uprating are examined. Attention is brought to the fact that many candidate nuclear power plants for uprating have anyway been operated below their rated power for a significant part of their operating life. The key issues remain safety and reliability in operation at all times, irrespective of the nuclear power plant's chronological or design age or power rating. The effects of power uprates are discussed in terms of material aspects and expected demands on the systems, structures and components. The impact on operation and maintenance methods is indicated in terms of changes to the ageing surveillance programmes. Attention is brought to the necessity checking or revising operator actions after power up-rating has been implemented.

A Study on the Establishment of a Standard for Road Projection Lighting Devices for School Buses (어린이 통학버스의 로드 프로젝션 등화장치 표준 제정에 관한 연구)

  • Panju Shin;Jaecheol Kim;Hyun Kim
    • Journal of Auto-vehicle Safety Association
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    • v.15 no.3
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    • pp.43-52
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    • 2023
  • When a children's school bus stops on the road, the operator enables an amber flashing light (indicating stopping or slowing) or a red flashing light (indicating that children are getting on and off). Drivers of vehicles passing by the stopped school bus, as well as vehicles in adjacent lanes to the school bus must stop temporarily. However, many drivers are not aware of the laws and do not comply with them, so children are exposed to an increased risk of being hit, especially at night as the color recognition of the vehicle is significantly lower than during the day. In our experiments, messages and shapes using light were projected to the front and rear of a parked school bus, in addition to its red lights flashing.

A Study on Memetic Algorithm-Based Scheduling for Minimizing Makespan in Unrelated Parallel Machines without Setup Time (작업준비시간이 없는 이종 병렬설비에서 총 소요 시간 최소화를 위한 미미틱 알고리즘 기반 일정계획에 관한 연구)

  • Tehie Lee;Woo-Sik Yoo
    • Journal of the Korea Safety Management & Science
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    • v.25 no.2
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    • pp.1-8
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    • 2023
  • This paper is proposing a novel machine scheduling model for the unrelated parallel machine scheduling problem without setup times to minimize the total completion time, also known as "makespan". This problem is a NP-complete problem, and to date, most approaches for real-life situations are based on the operator's experience or simple heuristics. The new model based on the Memetic Algorithm, which was proposed by P. Moscato in 1989, is a hybrid algorithm that includes genetic algorithm and local search optimization. The new model is tested on randomly generated datasets, and is compared to optimal solution, and four scheduling models; three rule-based heuristic algorithms, and a genetic algorithm based scheduling model from literature; the test results show that the new model performed better than scheduling models from literature.

Design and Implementation of OPC UA-based Collaborative Robot Guard System Using Sensor and Camera Vision (센서 및 카메라 비전을 활용한 OPC UA 기반 협동로봇 가드 시스템의 설계 및 구현)

  • Kim, Jeehyeong;Jeong, Jongpil
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.19 no.6
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    • pp.47-55
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    • 2019
  • The robot is the creation of new markets and various cooperation according to the manufacturing paradigm shift. Cooperative management easy for existing industrial robots, robots work on productivity, manpower to replace the robot in every industry cooperation for the purpose of and demand increases.to exist But the industrial robot at the scene of the cooperation working due to accidents are frequent, threatening the safety of the operator. Of industrial site is configured with a robot in an environment ensuring the safety of the operator to and confidence to communicate that can do the possibility of action.Robot guard system of the need for development cooperation. The robot's cooperation through the sensors and computer vision task within a radius of the double to prevent accidents and accidents should reduce the risk. International protocol for a variety of industrial production equipment and communications opc ua system based on ultrasonic sensors and cnn to (Convolution Neural Network) for video analytics. We suggest the cooperation with the robot guard system. Robots in a proposed system is unsafe situation of workers evaluating the possibility of control.

The Control Method of Rehabilitation Assistance Mobile Robot Using Force-Reflection Joystick (힘 반향 조이스틱을 이용한 재활보조용 이동 로보트의 제어 기법)

  • 이응혁;권오상;김병수;민홍기;장원석;홍승홍
    • Journal of Biomedical Engineering Research
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    • v.18 no.4
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    • pp.447-456
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    • 1997
  • When the disabled is operating a rehabilitation assisting system with a joystick by himself, unlike in the case of a normal person, tremor with joystick control or instant miscontrol can often occur. If these misoperations should be directly relayed to the system, shaking or malfunction of the mobile rehabilitation assisting system might be the result. The safety of the disabled is of prime concern. To solve this problem, that is, to prevent the miscontrol of the disabled operator and avoid crashes into his or her surroundings, we propose the force-reflection locomotion algorithm with the joystick. This method uses ultrasonic sensors to measure the distance between the object and mobile robot. Based on the reception of sensory data, the necessary torque is applied via the joystick to the attatched motor. To confirm the effectiveness of the proposed method, the subjects on the reflected force by the dynamic characteristics of the joystick and the reflected force by the distance information are tested Even though there are some differences in human dexterity, we confirmed the fact that the information from the obstacles was relayed to the operator via the joystick and resulted in an improved operational performance and safety level with regard to those obstacles.

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Motion Response Estimation of Fishing Boats Using Deep Neural Networks (심층신경망을 이용한 어선의 운동응답 추정)

  • TaeWon Park;Dong-Woo Park;JangHoon Seo
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.7
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    • pp.958-963
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    • 2023
  • Lately, there has been increasing research on the prediction of motion performance using artificial intelligence for the safe design and operation of ships. However, compared to conventional ships, research on small fishing boats is insufficient. In this paper, we propose a model that estimates the motion response essential for calculating the motion performance of small fishing boats using a deep neural network. Hydrodynamic analysis was conducted on 15 small fishing boats, and a database was established. Environmental conditions and main particulars were applied as input data, and the response amplitude operators were utilized as the output data. The motion response predicted by the trained deep neural network model showed similar trends to the hydrodynamic analysis results. The results showed that the high-frequency motion responses were predicted well with a low error. Based on this study, we plan to extend existing research by incorporating the hull shape characteristics of fishing boats into a deep neural network model.

Automatic identification of ARPA radar tracking vessels by CCTV camera system (CCTV 카메라 시스템에 의한 ARPA 레이더 추적선박의 자동식별)

  • Lee, Dae-Jae
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.45 no.3
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    • pp.177-187
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    • 2009
  • This paper describes a automatic video surveillance system(AVSS) with long range and 360$^{\circ}$ coverage that is automatically rotated in an elevation over azimuth mode in response to the TTM(tracked target message) signal of vessels tracked by ARPA(automatic radar plotting aids) radar. This AVSS that is a video security and tracking system supported by ARPA radar, CCTV(closed-circuit television) camera system and other sensors to automatically identify and track, detect the potential dangerous situations such as collision accidents at sea and berthing/deberthing accidents in harbor, can be used in monitoring the illegal fishing vessels in inshore and offshore fishing ground, and in more improving the security and safety of domestic fishing vessels in EEZ(exclusive economic zone) area. The movement of the target vessel chosen by the ARPA radar operator in the AVSS can be automatically tracked by a CCTV camera system interfaced to the ECDIS(electronic chart display and information system) with the special functions such as graphic presentation of CCTV image, camera position, camera azimuth and angle of view on the ENC, automatic and manual controls of pan and tilt angles for CCTV system, and the capability that can replay and record continuously all information of a selected target. The test results showed that the AVSS developed experimentally in this study can be used as an extra navigation aid for the operator on the bridge under the confusing traffic situations, to improve the detection efficiency of small targets in sea clutter, to enhance greatly an operator s ability to identify visually vessels tracked by ARPA radar and to provide a recorded history for reference or evidentiary purposes in EEZ area.

A Study on Occupational Stress of the VTS Operators (해상교통관제사의 스트레스 수준 측정에 관한 연구)

  • Kim, Yu-Sun;Park, Young-Soo;Jo, So-Hyun
    • Journal of Navigation and Port Research
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    • v.38 no.6
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    • pp.615-621
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    • 2014
  • VTS operators may suffer from acute, chronic, or traumatic stress caused by their workload and working environments associated with task or combination of task. This study intended to measure the level of VTS operator' stress and find out factors influencing it by understanding their characteristics during carrying out their task. For this purpose, analyzed the data collected through conducting survey on VTS operators as the Korea Occupational Stress(KOSS) and Psychological Well-being Index(PWI). As a result, VTS operators are experiencing higher level of psychological stress than the national average. And the factors to cause VTS operators' occupational stress can be summarized as follows; working environment factors, shift work especially night duty, workload, etc. This study provides the fundamental information for understanding human factors of VTS operator' occupational stress.

Automatic Recognition Algorithm of Unknown Ships on Radar (레이더 상 불특정 선박의 자동식별 알고리즘)

  • Jung, Hyun Chul;Yoon, Soung Woong;Lee, Sang Hoon
    • Journal of KIISE
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    • v.43 no.8
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    • pp.848-856
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    • 2016
  • Seeking and recognizing maritime targets are very important tasks for maritime safety. While searching for maritime targets using radar is possible, recognition is conducted without automatic identification system, radio communicator or visibility. If this recognition is not feasible, radar operator must tediously recognize maritime targets using movement features on radar base on know-how and experience. In this paper, to support the radar operator's mission of continuous observation, we propose an algorithm for automatic recognition of an unknown ship using movement features on radar and a method of detecting potential ship related accidents. We extract features from contact range, course and speed of four types of vessels and evaluate the recognition accuracy using SVM and suggest a method of detecting potential ship related accidents through the algorithm. Experimentally, the resulting recognition accuracy is found to be more than 90% and presents the possibility of detecting potential ship related accidents through the algorithm using information of MV Sewol. This method is an effective way to support operator's know-how and experience in various circumstances and assist in detecting potential ship related accidents.

Transient Diagnosis and Prognosis for Secondary System in Nuclear Power Plants

  • Park, Sangjun;Park, Jinkyun;Heo, Gyunyoung
    • Nuclear Engineering and Technology
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    • v.48 no.5
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    • pp.1184-1191
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    • 2016
  • This paper introduces the development of a transient monitoring system to detect the early stage of a transient, to identify the type of the transient scenario, and to inform an operator with the remaining time to turbine trip when there is no operator's relevant control. This study focused on the transients originating from a secondary system in nuclear power plants (NPPs), because the secondary system was recognized to be a more dominant factor to make unplanned turbine-generator trips which can ultimately result in reactor trips. In order to make the proposed methodology practical forward, all the transient scenarios registered in a simulator of a 1,000 MWe pressurized water reactor were archived in the transient pattern database. The transient patterns show plant behavior until turbine-generator trip when there is no operator's intervention. Meanwhile, the operating data periodically captured from a plant computer is compared with an individual transient pattern in the database and a highly matched section among the transient patterns enables isolation of the type of transient and prediction of the expected remaining time to trip. The transient pattern database consists of hundreds of variables, so it is difficult to speedily compare patterns and to draw a conclusion in a timely manner. The transient pattern database and the operating data are, therefore, converted into a smaller dimension using the principal component analysis (PCA). This paper describes the process of constructing the transient pattern database, dealing with principal components, and optimizing similarity measures.