• Title/Summary/Keyword: school safety accident

Search Result 667, Processing Time 0.027 seconds

The Arms Race on the Road: Exploring Factors of SUVs' Popularity by LDA Topic Model (도로 위의 군비경쟁: LDA 토픽모델을 활용한 SUV의 인기 요인 탐구)

  • Jeon, Seung-Bong;Goh, Taekyeong
    • Journal of Digital Convergence
    • /
    • v.18 no.10
    • /
    • pp.239-252
    • /
    • 2020
  • By using text mining, we explore the factors responsible for an increase in SUV preference. We collected 32,679 posts related to SUVs from "Bobaedream," the largest online automobile community in South Korea, and applied the LDA topic model. While previous studies have explained the SUV boom as an individual's risk aversion strategy from crime, the result shows that the topic of 'Safety' appears to be an important factor in the SUV discourse in the context of a car accident and high-speed driving situation. To conclude, the consumption of SUVs in Korean society serves as a mean to prevent anxiety and danger to individuals when driving. We insist that decreasing social trust, caused by an increase in inequality, underlies the perception of risk on the road.

A Study on the Development of the Position Detection System of Small Vessels for Collision Avoidance (충돌 회피를 위한 소형 선박의 위치 검출 시스템 개발에 관한 연구)

  • Le, Dang-Khanh;Nam, Teak-Kun
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.20 no.2
    • /
    • pp.202-209
    • /
    • 2014
  • In this paper, a developed device for detecting target's location and avoiding collision is proposed. Velocity and acceleration model of target are derived to estimate target's information, i.e. position, velocity and acceleration considering process and measurement noise. Kalman filtering method applied to the estimation process and its results was confirmed by simulation. The distance measurements system using laser sensor for moving target system is also developed to confirm the effectiveness of the proposed scheme. Experiments to get information of moving target with velocity and acceleration model was executed. The data with filtering and without filtering was compared by experiments. Discontinuous measured data was changed to smooth and continuous data by Kalman filtering. It is confirmed that desired data was obtained by applying proposed scheme. UI for measuring and monitoring the target data is developed and visual and auditory alarm function is attached on the system Finally, position estimation system of moving target with good performance is achieved by low price equipments.

Methodology for Near-miss Identification between Earthwork Equipment and Workers using Image Analysis (영상분석기법을 활용한 토공 장비 및 작업자간 아차사고식별 방법론)

  • Lim, Tae-Kyung;Choi, Byoung-Yoon;Lee, Dong-Eun
    • Korean Journal of Construction Engineering and Management
    • /
    • v.20 no.4
    • /
    • pp.69-76
    • /
    • 2019
  • This paper presents a method that identifies the unsafe behaviors at the level of near-misses using image analysis. The method establishes potential collision hazardous area in earthmoving operation. It is implemented using a game engine to reproduce the dangerous events that have been accepted as major difficulty in utilizing computer vision technology to support construction safety management. The method keeps realistically track of the ever-changing hazardous area by reflecting the volatile field conditions. The method opens a way to distinguish unsafe conditions and unsafe behaviors that have been overlooked in previous studies, and reflects the causal relationship which causes an accident. The case study demonstrate how to identify the unsafe behavior of a worker exposed to an unsafe area created by dump trucks at the level of near-misses and to determine the hazardous areas.

Comparison of factors affecting residential and residential environment satisfaction by region using the CART algorithm (CART 알고리즘을 이용한 지역별 주택 및 주거환경 만족도 영향 요인의 비교)

  • Jung su eun
    • The Journal of the Convergence on Culture Technology
    • /
    • v.9 no.4
    • /
    • pp.707-715
    • /
    • 2023
  • This study utilized CART algorithm, a decision tree analysis method, to comparatively analyze factors affecting housing and residential environment satisfaction by region using data from Ministry of Land, Infrastructure and Transport's housing survey in 2020. First, in terms of residential environment satisfaction, accessibility to medical facilities and school district showed higher importance in metropolitan cities and areas compared to other regions, whereas safety from accident showed the opposite trait, showing difference between region. Second, housing characteristics were important in housing satisfaction, indoor environment level satisfaction and indoor safety and hygiene being important in almost all regions, while residential environment characteristics were more important in residential environment satisfaction and influencing factors were relatively evenly distributed. In order to generalize these regional characteristics, research using time series data needs to be conducted later.

Thermal-hydraulic phenomena and heat removal performance of a passive containment cooling system according to exit loss coefficient

  • Sun Taek Lim;Koung Moon Kim;Jun-young Kang;Taewan Kim;Dong-Wook Jerng;Ho Seon Ahn
    • Nuclear Engineering and Technology
    • /
    • v.56 no.10
    • /
    • pp.4077-4086
    • /
    • 2024
  • The natural circulation system has been widely studied for use in various applications because of its inherent advantage. However, it has a key weakness called flow instability that makes the system unstable. Through massive previous research, the mechanisms of flow instability were analyzed, but there was an ambiguous aspect related to the effect of experimental parameters on the phenomenon. Particularly, there has been no report on the heat transfer performance of the system when flow instability phenomena were present. In this study, thermal-hydraulic phenomena of a two-phase natural circulation system that functions as a passive containment cooling system (PCCS) was investigated according to experimental parameters, namely, the temperature boundary (120-158 ℃) and exit loss coefficient (0-34.5) under atmospheric pressure conditions. The experimental results showed five different flow types in the loop. The flow modes that occurred by the interaction between flashing and boiling were classified by referring to the mass flow rate, void fraction, and visualization data. The system was more unstable when the temperature boundary conditions increased, but it was more stable when the exit loss coefficient increased. These results have only been confirmed in our research. The reason for the results is that the flow conditions are located on the boundary between Density Wave Oscillation I and the stable flow region, and that boundary does not have clear criteria. In addition, comparing the heat transfer performance of a system by heat rate can confirm the effect of flow instability on the thermal performance of the passive cooling system. As a result, the high exit loss coefficient stabilizes the system better than the low case and has similar heat removal performance.

Assessment of the MELCOR 1.8.6 condensation heat transfer model under the presence of noncondensable gases (중대사고 해석코드 MELCOR 1.8.6의 비응축성기체 존재 시 응축열전달 모델 평가)

  • Yoo, Ji Min;Lee, Dong Hun;Yun, Byong Jo;Jeong, Jae Jun
    • Journal of Energy Engineering
    • /
    • v.25 no.2
    • /
    • pp.1-20
    • /
    • 2016
  • A condensation heat transfer model is very important for the safety analysis of nuclear power plants. Especially, condensation under the presence of noncondensable gases (NCGs) is an important issue in nuclear safety because the presence of even a small quantity of NCGs in the vapor largely reduces the condensation rate. In this study, the condensation heat transfer model of the severe accident analysis code MELCOR 1.8.6 has been assessed using a set of condensation experiments performed under the thermal-hydraulic conditions similar to those inside a containment during design-basis accidents or severe accidents. Experiment conditions are categorized into 4 types according to the shape of the condensation surface: vertical flat plates, outer surface of vertical pipes, inner surface of vertical pipes, the inner surface of horizontal pipes. The results of the calculations show that the MELCOR code generally under-predicts the condensation heat transfer except the condensation on inner surface of vertical pipes.

A Survey on the Knowledge and Attitude of Workers Concerning Occupational Health (근로자의 산업보건 지식과 태도에 관한 조사연구)

  • 박영식;조수열;남철현
    • Journal of Environmental Health Sciences
    • /
    • v.18 no.2
    • /
    • pp.3-18
    • /
    • 1992
  • This research was carried out on 1,017 production workers for four months from May to August, 1991, to search more effective management method of their health by grasping their knowledge and attitude on industrial health. The results of this study can be summarized as follows: 1. As for general characteristics, 74.2% were male and 25.8% were female among the 1,017 workers. The two largest age groups were 30~39, 38.7%. As for education level, graduation from high school was 58.6%, 61.2% were married, 35.9% owned their house, and workers who worked more than 1 year less than 5 years was 52.9%, workers who worked 8 hours a day was 46.7%, the largest group income level was 60~69 thousand won 21.2%, and the degree of satisfaction with work was ordinary, 45.6%. 2. The degree of recognition concerning occupational diseases was 92.5% at a very high rate. Causes of occupational diseases under the present work field were in order of noise, dust, heavy metal. The largest group of the counterplan for prevention was an improvement of working environment, 62.0%. 3. The major cause that threatens worker's health was poor working environment, 31.4%. As the best method for workers' health management, working environment management was pointed. 4. As for health examination result, the response that it is of use to health management was 53.8%. As for examination method and result, 42.7% responded that they are formal. The practice period was more than once every six months as the largest group, and the highest desire for improvement was that they wants an exact information of the result. 5. 49.3% of the respondents know about the measurement of working environment an the response that the measurement is necessary to improve working environment was 57.9%, and that the results from the measurement were reflected on improvement an management 57.5%. Appropriate period to take a measurement was more than once per six months, 40.2% and per three months, 29.1%. 6. As for safety and halth instruction, 34.5% were educated for both, 38.2% for only safety education and just 4.6% for only health education. 51.9% responded that they had never been educated out of work place. The period of its practice was more than once a month, 39.5% and every three months, 21.3%. 7. The importance of safety and health showed that the one is equal to the other, 59.8%, that the one is more important, 29.6%, and that other is more important, 7.6%. 67.7% said the necessity of a safety and health manager. 8. In spite of more or less health obstacle of work environment, 14.9% of the respondents wanted to overwork to gain an allowance for over-time work, 39.9% didn't, and 40.2% according to condition and state. 9. As the most important cause of industrial accident, 40.2% indicated unsafe behavior. As for the individual protective instrument, 66.1% of all the respondents said they have worn it to protect industrial diseases. 10. As for the degree of understanding of the contents in Industrial Safety and Health Law and Industrial Law of Accident Insurance, an affirmative response was respectively 49.3% and 50.8% and the sources of safety-health information were televisions and radios, 28.0%. Therefore, it is necessary that we do positive working environmental improvement, continuous management and health education's inforcement to increase their health and prevent occupational diseases.

  • PDF

Development of an IoT Smart Sensor for Detecting Gaseous Materials (사물인터넷 기술을 이용한 가스상 물질 측정용 스마트센서 개발과 향후과제)

  • Kim, Wook;Kim, Yongkyo;You, Yunsun;Jung, Kihyo;Choi, Won-Jun;Lee, Wanhyung;Kang, Seong-Kyu;Ham, Seunghon
    • Journal of Korean Society of Occupational and Environmental Hygiene
    • /
    • v.32 no.1
    • /
    • pp.78-88
    • /
    • 2022
  • Objectives: To develop the smart sensor to protect worker's health from chemical exposure by adopting ICT (Information and Communications Technology) technologies. Methods: To develope real-time chemical exposure monitoring system, IoT (Internet of Things) sensor technology and regulations were reviewed. We developed and produced smart sensor. A smart sensor is a system consisting of a sensor unit, a communication unit, and a platform. To verify the performance of smart sensors, each sensor has been certified by the Korea Laboratory Accreditation Scheme (KOLAS). Results: Chemicals (TVOC; Total Volatile Organic Compounds, Cl2: Chlorine, HF: Hydrogen fluoride and HCN: Hydrogen cyanide) were selected according to a priority logic (KOSHA Alert, acute poisoning statistics, literature review). Notifications were set according to OEL (occupational exposure limit). Sensors were selected based on OEL and the capabilities of the sensors. Communication is designed to use LTE (Long Term Evolution) and Wi-Fi at the same time for convenience. Electronic platform were applied to build this monitoring system. Conclusions: Real-time monitoring system for OEL of hazardous chemicals in workplace was developed. Smart sensor can detect chemicals to complement monitoring of traditional workplace environmental monitoring such as short term and peak exposure. Further research is needed to expand the scope of application, improve reliability, and systematically application.

A Fundamental Study on the Improvements of Speed Limit at the Ports and Fairways in Korea (항만과 수로의 제한속력 개선방안에 관한 기초 연구)

  • Kim, Deug-Bong;Yun, Byeong-Won;Jeong, Jae-Yong;Park, Jin-Soo;Park, Young-Soo
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.18 no.5
    • /
    • pp.423-430
    • /
    • 2012
  • The purpose of Speed limit at sea is to keep harbor calmness, to maintain efficient traffic flow and to prevent maritime accidents. The Korean Regional Maritime Affairs and Port Office(KRMAPO) specified and enforced the ship's speed limits at the 19 harbors around the Korean coasts. However, problems have been raised to the adequacy of speed limits. This paper made a research on the speed limit set standards, analyzed vessel traffic survey and the dilemma on the specified speed limits imposed by KRMAPO. The result of this study has shown an overall average of 48 % violation rate on speed limit with passenger ships and large vessels of more than 5,000 tons having higher violation rate. Average speed was higher than the limit speed in some harbors and deviation of 4.2 to 5.2 knots was investigated. Further, harbors having higher average speed also have higher deviation accident incidence. Therefore, this paper had confirmed that there is a need for institutional review and improvement of Korea's port and fairways speed traffic management.

A Study on the Sea-sickness Susceptibility of Seafarer at the Wheel House and Engine Room (조타실과 기관실 근무자의 뱃멀미 민감성에 대한 연구)

  • Kim, Deug-Bong;Kim, Bu-Gi;Rim, Geung-Su;Kim, Hong-Ryoel;Kim, Chang-Su
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.20 no.1
    • /
    • pp.42-48
    • /
    • 2014
  • Seasickness not only makes persons on board vessels to vomit but also causes vertigo, headache, sleepiness, fatigue, lethargy and other discomforts. This ailment leads to disturbance of biorhythm and decline of perception which would eventually cause reduction of situational awareness among ship's operators that leads to marine accident. This study is about the sensitivity of people onboard ships to seasickness and focused on deck or navigation officer cadets(apprentice officers) and engine officer cadets(apprentice engineers) who have no previous experiences on board. It is conducted by using motion sensor that can measure ship's X, Y, Z-axis motions and through the questionnaire survey, and evaluated each students' degree of seasickness symptoms. Through this study, in same circumstance, we have known that there are different degrees of motion sickness for wheel house worker and engine room worker, It also confirmed that seasickness have high relationship with degree of hull motion and also, with cycle of hull motion. In addition, we have confirmed that Z-axis hull movement has higher relationship with seasickness than X-axis and Y-axis hull movements. This study aims to initiate additional researches about X-axis and Y-axis of the ship's motion which it expects to greatly enhance safety of wheelhouse and engine room personnel, ship's livability and comfortable sailing.