• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.19 no.2
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• pp.99-105
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• 1983

In the Steering and Sailing Rules of International Regulations for Preventing Collicions at Sea, 1972, any relative distance between two vessels necessary for taking action to avoid collision in head-on situation is not referred. In this paper, the author analyzed the ship's collision avoiding actions from a viewpoint of ship motions and worked out mathematical formulas to calculate the relative distances necessary for collision avoiding actions. Figuring out the values of maneuvering indices through experiments of actual ships, the author applied these values to the calculationg formulas and calculated the minimum safe relative distances. On the assumption that two vessels same in size and condition are approaching each other in head-on situation, the minimum safe relative distance was calculated as 5.0 times, sufficient safe relative one as 10.0 times their own length.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.2
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• pp.202-209
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• 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.

• Journal of the Korean Institute of Gas
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• v.16 no.3
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• pp.29-34
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• 2012

Investigating safer ways to design and use to prevent a loss of life and property by failure of the structures are necessary and assessing total fatigue life with initiation and propagation of fatigue crack accurately through fatigue analysis is very important. The object of this study is to examine the initial life and propagation life when the fatigue crack is introduced from the root which is likely to appear in LOP(Lack of Penetration) cruciform fillet welded structure including bridges, ships and gas storage facilities which are impossible to be fully penetrated and to measure the rate of fatigue life until the final cleavage failure. As the result, each rate of fatigue life for fatigue failure is somewhat different in the range of 5% according to the thickness of material, however, the overall rate of initial life is in the range of 34~39% and propagation life showed the range of 61~66%.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2017.11a
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• pp.329-330
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• 2017

재난은 인류의 발전과 더불어 다양하게 발생되어왔다. 최근 21세기 들어 발생하는 재난은 그 현상이 더욱 다양하고 복잡하며 그 피해의 정도가 대규모로 진행되는 경우가 많아 졌다. 태풍, 집중호우, 강풍, 폭설, 지진, 황사 등의 자연재난은 지구온난화현상으로 국내뿐만 아니라 전 세계적으로 커다란 영향력을 미치고 있으며, 화재, 구축물의 붕괴, 지하철사고, 테러 및 감염병 등의 사회 재난도 더욱더 증가하고 있는 추세이다. 나아가 사스, 메르스, 지카 바이러스 및 대형 테러 등 전 세계적 차원의 사회 재난의 발생 또한 급증하고 있다. 이와 같이 현대사회에서 발생하는 재난는 개인이나 국가의 정책만으로 예방하고 관리할 수 없는 특성이 있다. 따라서, 자본주의 경제의 한축을 이루고 있는 기업의 재난을 관리하여 연속성을 확보하고 더나아가 리질리언스(Resilence)를 보장하기 위한 일환으로 2007년 7월 재해경감을 위한 기업의 자율 활동 지원에 관한 법률(이하, 기업재해경감법 이라함.)이 공포된 지 약 10여년이 경과하였다. 이는 법 제도화를 통하여 기업의 재해경감활동을 지원하기 취지에서 출발한 것 이다. 그 후 현재 까지 어느 정도의 발전이 있었지만 경과 년 수에 비해 아직 미흡한 실정이다. 이후 그 기업들이 좀 더 원활하게 재해경감활동을 위한 계획을 수립, 실행, 검토 및 유지하기 위한 지침으로서 기업재난관리표준을 2010년 4월 2일 제정하였고 이후 재해경감활동 수립계획을 제정하여 시행하기에 이르렀다. 또한, 기업재난관리표준은 제정된 이후 2013년 12월 9일 전면 개정작업을 통해 경영관리 프로세스 모델(Plan-Do-Check-Act)이 적용된 관리체계를 접목시키고 용어정의를 국제표준과 일치시켜 기업재해경감활동 상의 혼선을 방지하기 위한 노력을 하였다. 현 정부에서는 주무부처가 바뀌고 조직이 변화되어 행정안전부고시 제2017-1호(2017.07.26.일)로 개정되어 현재에 이르고 있다. 본 논문에서는 기업재난관리표준과 연관된 제반 법령 및 규정 등에 대한 법적성격 과 지위를 규명하고, 기업재난관리표준의 관련분야 적용 시 문제점 및 바람직한 제도개선 방향을 제시하고자 한다.

• Journal of the Korean Institute of Gas
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• v.13 no.6
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• pp.15-20
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• 2009

The number of compressed natural gas (CNG) vehicles have increased gradually by virtue of korea government's urban air quality improvement policy since 1998. Although the use of CNG as transportation fuel gives environmental benefits, there is a possibility of huge accidents from unexpected fire. Therefore, needs for the guarantee of safety are indispensible for the reliable operation of CNG vehicles. A check valve is a safety device which prevents leakage of the pressurized fuel charged in a fuel tank. Durability of this component should be guaranteed in spite of repeated operation. This research has performed durability tests of a CNG check valve regarding the repeated usage, extreme chattering, and the effect of compressor oil.Although a check valve used for CNG vehicle satisfies validation requirements in the test results, it has been found that problem in the function of leakage prevention in a check valve could take place in the case of prolonged exposure to compressor oil.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.11
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• pp.2119-2124
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• 2008

An information-oriented basis in today's society has been changing fast, and the desire for connectivity has caused an exponential growth in wireless communication and sensor network. Sensor networks using RFID, in particular, have led this trend due to the increasing exchange of data in Ubiquitous such as the home RF, access control system, U-Healthcare, and Logistics information Systems. Also, the RFID when it applies a technique, is able to raise the stability of shipping as controling the mobile course and an entrance and exit of the crews an well as previously preventing an accident from shipping. In this paper, we designed and implemented personnel control system using UHF-RFID in vessels which shows through host PC reading and writing tag.

• Tunnel and Underground Space
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• v.29 no.1
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• pp.30-37
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• 2019

Some leading countries in mining have a very quantitative guideline for underground mine opening design which is useful to minimize mine hazards such as rockfall and collapse. Those hazards sometimes can cause a huge damage on human life and property in the mines. Construction guidelines of underground mines in Korea consist of qualitative and general expressions although the workers' safety rules and guides are well provided. Recently, mining operations in Korea are going underground due to the environmental regulations and resource depletion at shallow depth, and therefore there is a growing demand on a specialized and systematic guideline for mine opening design securing the underground stability. In this paper, current status of mining industry, research trends, and mining guidelines in Korea and overseas have been reviewed to give an insight into developing a new Korean guideline for underground mine design.

• Journal of IKEEE
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• v.23 no.1
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• pp.107-111
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• 2019

In FPD WET equipment, heaters are used a lot. There are many electric accidents caused by short circuit and overheating due to the use of heater, so it is necessary to have a safe electric system and interlock. Therefore, in this paper, we propose an electrical schematic and interlock for FPD WET equipment. In this paper, a hardware interlock such as a level sensor, an overheat protector, and an SSR heater sink is inserted, and the electric system is composed of ELB - MC - SSR - EOCR - heater. When the interlock occurs, the magnetic contactor (MC) is turned off and the power of the heater is cut off.EOCR, an electric overcurrent protection device, has an interlock to shut down the MC when there is an abnormality in the heater while checking the overcurrent, undercurrent and disconnection. These circuit configurations and interlocks are likely to be useful not only for WET equipment but also for any equipment in which the heater is placed.

• Proceedings of the Korea Information Processing Society Conference
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• 2020.11a
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• pp.548-551
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• 2020

최근 의료시장에 상용화된 모바일 수술 중 CT(intra-operative computed tomography, iCT)는 수술실 내 이동이 자유로울 뿐만 아니라 수술 후 즉각적인 환자 모니터링이 실시간으로 이루어져 수술 후 환자의 예후 향상과 재수술 확률을 낮출 수 있다. 이동성을 갖춘 iCT 는 편의성과 유용성이 검증되었지만, 이동시 발생될 수 있는 충돌사고의 단점이 존재한다. 따라서, iCT 의 이동시 발생할 수 있는 위험을 최소화 할 수 있는 안전장치가 요구된다. 본 연구에서는 모바일 iCT 의 구동 제어의 편의성과 안전성을 확보 할 수 있는 CT 촬영을 제어하기 위한 리모트 컨트롤러, 이동시 전방 시야를 확보하기 위한 전방 모니터링 카메라 출력, 충돌 위험을 알릴 수 있는 초음파 센서를 통합하는 임베디드 컨트롤러를 개발하고자 한다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.10a
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• pp.262-265
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• 2021

The purpose of this development is to prevent accidents in the telephone poles caused by bird nests in advance. It is a sensor node installed on a telephone pole to recognize a bird's nest. This is to remove the bird before it builds a nest and lays eggs. It is in the system that recognizes the bird nest by the change of the distance when the sensor is first installed and the distance value measured thereafter. In this paper, we have designed and tested infrared rays with concrete, iron plate, wood, and plastic bag are targeted. This is an object that can be detected within a telephone pole was tested. The value of the spectrum detected by the spectral reflectance was obtained through a photodiode. Through the standard deviation graph of these values, it became possible to predict the target of the object and measure the distance. As a result of this experiment, target information (concrete, iron plate, wood, plastic bag) about dangerous substances in the telephone pole was acquired through the infrared sensor. Through this, it is expected that it will contribute to the establishment of a safe power grid and a coexistence environment with nature through power grid monitoring.