• Journal of the Korean Society of Safety
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• v.27 no.5
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• pp.16-21
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• 2012

The purpose of this study is to try to find the risk of roller(mixing mill) in working site. In order to achieve the purpose, accident analysis and survey was carried out. This analysis revealed that average of loss days is 334.3 by roller jamming accident and 229.2 by other causes. It means jamming accident entails serious bodily harm. According to our research, we realize that most of rollers have some risk of the jamming accidents. It is simply because the roll gap in the roller is not more than 10cm. It also does not meet minimum distance so as to avoid the risk for jamming accident by KS. Furthermore, 28% of rollers have only one switch and 40% of rollers have two switches operating emergence stop equipment so as to reduce the risk of jamming accidents. Therefore, we presume that it is very difficult to turn on the switch of emergence stop equipment when they confront the accident because most of engineers are working alone.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.2
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• pp.79-94
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• 2021

A GNSS receiver installed in autonomous vehicles is the most essential device for its navigation. However, if an intentional jamming signal is generated, there is a risk of exposure to an accident risk due to deterioration of the GNSS sensor's performance. Research is required to prevent this, and accordingly, a jamming generating device must be provided. However, according to the provisions of the law related to jamming, this is illegal. In this paper, we implement an in-vehicle jamming device that complies with the provisions of the law and does not affect the surrounding GNSS sensors. Driving simulation is used to evaluate the performance of the GNSS algorithm, and the malfunction of autonomous vehicles occurring in the interference environment and data errors output from the GNSS sensor are analyzed.

• Journal of the Society of Naval Architects of Korea
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• v.54 no.4
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• pp.301-311
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• 2017

Safety operational envelope (SOE) is the area which guarantees the safety of a submarine from the accident such as jamming and flooding. The maximum safe depth is set to prevent the damage to the hull from increasing water pressure with depth. A minimum safety depth is set to prevent a submarine from the exposure above the free surface and collision against surface ship. The prediction method for the SOE in the design phase is needed to operate the submarine safely. In this paper, the modeling and calculation methods of the SOE are introduced. Main ballast tank blowing modeling and propeller force modeling are conducted to simulate the accidents and the recovery process. The SOEs are established based on the crash stop and emergency rising maneuver simulation. From the simulation results, it can be known that the emergency rising maneuver is more effective recovery action than the crash stop.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.11a
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• pp.490-493
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• 2011

공연과 스포츠 문화의 발전으로 한정된 구역에 불특정 다수의 사람들이 모이는 일이 빈번하게 일어나고 있다. 이에 비례하여 불특정 다수의 압사사고 역시 자주 일어나고 있다. 이러한 압사사고는 인도, 일본, 독일 등 세계 곳곳에서 일어나며, 국내에서도 자주 발생하는 압사사고는 단순히 안전불감증 문제로만 치부되어 특별한 과학적 해석이 행해지지 않는 문제점을 가지고 있다. 이러한 압사사고는 보행자의 심리와 물리적 충돌에 의한 힘에 의하여 일어나는 특징을 가지고 있다. 따라서 본 연구에서는 집합행동심리를 고려한 이산요소법을 활용하여 과밀상태하의 병목구간에서의 보행자 피난 유동 해석 연구를 진행한다. 연구의 변수로는 출구의 폭, 출구 각도 그리고 보행자의 혼란정도를 나타내는 Panic Factor가 선택되었다.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.5
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• pp.35-42
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• 2018

In order to seek out methods to reduce safety accidents caused by construction machinery and equipment, this study collects data about safety accidents and draws main risk factors by construction from the data, through SNA. It aimed to suggest safety management points to be used in future construction fields, by analyzing risk index of such factors. The finding can be summarized: First, Backhoe Bucket is the risk factor for crash accidents of average workers in earth works; boring machines-maintenance is the risk factor for fall accidents of construction machinery operators in foundation works; bending machine-reinforcing rod processing is the risk factor for jamming accidents of reinforcing rod engineers in frame works; and mobile crane-hook is the risk factor for crash accidents of average workers in lifting works. Second, works can be arranged in turn, according to the risk index: earth, lifting, frame and foundation works. Risk factors can be also arranged according to the risk index: Backhoe in earth works, pile drivers in foundation works, bending machines in frame works and mobile cranes in lifting works. This study has some limits, in that it only analyzed main machinery/equipment, among various kinds of them, for earth, foundation, frame and temporary works (lifting works) and used data collected over three years. Therefore, it is necessary to conduct an analysis using big data, by collecting additional data about a lot of machinery/equipment in future construction fields.

• Journal of the Korea Construction Safety Engineering Association
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• s.45
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• pp.60-70
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• 2008

Mechanized tunnelling by TBMs has been extensively adopted for last two decades. Nevertheless, only few case histories have been reported. Unlike NATM tunnels, the case histories of the weak zone have been seldom reported for the mechanized tunnelling, even in the other countries. In this study, a collapse of TBM tunnel occurred in the severely altered weak rock zones between volcaniclastic rocks and granitic rocks was briefly described. A systematic geotechnical investigation, which was performed to examine the cause of the collapse, was carried out at the site and then characteristics of the rocks in the zones were evaluated. Moreover, This study propose a guide line of estimateing the possibility of collapse in TBM tunnels through comparing experimental results with surveying results of general rocks.

• Journal of Satellite, Information and Communications
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• v.12 no.2
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• pp.99-103
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• 2017

Recently, acccording to price decline and miniaturization of drone, it is increased dramatically that drone usage in various category including military and private sectors. In accordance with popular usage, There is a increasing risk of safety accident, national security and public privacy problem. Hence there is a high demand for study and analysis applicable to the related technology and anti-drone method including drone detection and jamming. In general, it is extremely difficult to detect and recognize drones using conventional sensors. In this paper, we classify drone detection technology and Drone detection experiments are performed using CW RADAR to obtain and analyze micro-doppler pattern. This preliminary study aims to provide fundamental theory on radar drone detection and experimental test results such that in-depth anti-drone technology can be established in future.

• Journal of the Korea Institute of Building Construction
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• v.23 no.1
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• pp.81-92
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• 2023

According to the 2020 industrial accident reports of the Ministry of Employment and Labor, the number of fatal accidents in the construction industry over the past 5 years has been higher than in other industries. Of these more than 50% of fatal accidents are initially caused by fall accidents. The central government is intensively managing falling/jamming protection device and the use of personal protective equipment to eradicate the inappropriate factors disrupting safety at construction sites. In addition, although efforts have been made to prevent safety accidents with the proposal of the Special Act on Construction Safety, fatalities on construction sites are constantly occurring. Therefore, this study developed a model that automatically detects the wearing state of the worker's safety helmet and belt using computer vision technology. In considerations of conditions occurring at construction sites, we suggest an optimization method, which has been verified in terms of the accuracy and operation speed of the proposed model. As a result, it is possible to improve the efficiency of inspection and patrol by construction site managers, which is expected to contribute to reinforcing competency of safety management.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.454-461
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• 2017

The purpose of this study is to investigate the types of domestic safety accidents involving children and to verify the difference of safety knowledge according to variables of parents. Subjects include 226 parents who have 3-5 year old infants enrolled in kindergartens and day care centers in I-city, Jeollabuk-do. The study tools are modified and complemented questionnaire for the study purpose referred to the preceding research data and the literature. For the processing of collected data, frequency analysis, descriptive statistics, one-way ANOVA, and the Duncan post-test were utilized using the SPSS program. The results of this study are as follows: First, safety accidents occurred at the majority of homes which have infant children. On average, the occurrence frequency was 1.78 times per six months. The accidents involving infants occurred in the order of drop or slip, crash or impact, stricture or jamming, fall, stab or cut, burn, swallow or inhalation. Second, both parents had an average level of safety knowledge. There was a distinction in the areas of 'fall' and 'first aid' according the mother's age. In addition, stay-at-home mothers had the higher level of safety knowledge compared with working mothers in the areas of 'general safety knowledge' and 'fire'. There was a distinction in the area of 'fire' according to the father's age. Given these findings, safety training programs for parents to improve safety knowledge needs to be developed.