• International Journal of Fluid Machinery and Systems
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• 제10권3호
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• pp.296-306
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• 2017

Hydropower is now changing its role from the energy generator into the most powerful and reliable tool for stabilizing the electrical network, especially under the increase of intermittent power sources like wind-power and solar-power. Although the hydropower plants are the most robust generating facilities, they are not immune from unexpected severe incidents having long downtime, considerable restoration cost and sometimes fatalities. The present paper provides some study results about severe incidents in the conventional hydropower plants, mainly about the flood, fire and electro-mechanical troubles, except for the incidents of civil facilities. It also provides some possible scenarios which may lead some measures how to avoid such incidents. Finally, it provides some comprehensible recommendations to avoid severe incidents based on experiences.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2009년도 춘계학술발표회 논문집
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• pp.65-73
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• 2009

The terrestrial laser scanner measures the signal delay time of electronic circuit in EDM(Electronic Distance Measurement) Module for distance measurement. To measure signal delay time precisely, transmitting laser beam of terrestrial laser scanner is divided optically. Therefore, 10% of the laser beam power is entered into the electronic circuit and the others go out through lens. But, measure of delay time is severe in the laser scanner system that the laser beam power is changed dynamically by reflectance of a object, because characters like gain of electronic circuit involving APD(Avalanche Photo Diode) and so on are changed by incident laser beam. Therefore, we adapt ND(Neutral Density) filter that has grid pattern to the laser scanner system to keep constant the incident laser beam power. In this paper, we propose the simulation program for efficient design of ND filter pattern. Finally, to affirm simulation program, we conduct the experimental test of simulated ND filter that has linearly transmittance change, and we consider the experiment result.

• Environmental Analysis Health and Toxicology
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• 제31권
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• pp.15.1-15.6
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• 2016

A number of absurdities surrounding the humidifier disinfectant (HD) incident may have occurred because 1) a judicial system operates on the underlying false assumption that the involved parties are equals in knowledge, information and resource mobilization capabilities, regardless of respective real status as company or individual; 2) there is a lack of a system that mandates a company to prevent and actively manage possible catastrophes; 3) the regulatory scheme makes companies believe that as long as they are complying with the existing regulations, they have satisfied all of their responsibilities. I believe that this issue is an opportunity to bring about changes in the judicial redress system, the system of internal management of manufacturers, and the regulatory system of the government. The following regulation amendments are needed to move towards the changes stated above. First, legislation relating to victim relief that is applicable to the HD incident must be established. Second, a risk management system must be formed within the manufacturing company and to this end an institutional environment for the system must be established within regulatory framework. Furthermore, legislation must be passed that could punish companies themselves that have caused severe damage to individuals because they had failed to take necessary actions to avoid foreseeable harm. Finally, the framework of regulation must be changed so that the company, who has the necessary information regarding the product and the component chemicals used in the product, must self-directed experiment and assessment of the safety of their own products.

• 디지털융복합연구
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• 제10권6호
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• pp.205-211
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• 2012

허베이스피리트호 사고로 인해 원유 $12,547k{\ell}$가 해상에 유출되어 총 4만여 가구의 주민들이 피해를 입었으며, 태안군을 포함한 11개 시 군이 특별재난구역으로 선포되었다. 이러한 대형 유류오염사고는 자연환경파괴 뿐만 아니라 지역의 주변환경 변화에 중대한 영향을 주게 된다. 본 연구에서는 허베이스피리트호 유류오염사고 피해가 가장 큰 지역인 태안을 중심으로 유류오염사고가 피해지역 주변환경에 미치는 영향을 조사 분석하였다. 조사항목은 크게 인구변화, 지역경제변화, 주민건강영향, 지역사회갈등 등으로 구분하여 수행하였다. 이러한 분석결과는 향후 유류사고 발생시 피해지역에 미치는 직 간접적인 영향을 예측하고 정부의 효율적인 정책방안을 수립하는데 매우 중요한 요소로 활용될 수 있을 것이다.

• 대한기계학회논문집
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• 제11권1호
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• pp.118-123
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• 1987

본 연구에서는 새로 고안된 연료주입기(air injector)바로 뒤에 입사압축파를 반사시키기 위한 벽을 설치하므로써 고체입자의 입사압축파에 대한 노출을 최대한 줄 였고 또한 새로운 연료주입기에 의해 매우 잘 분포된 입자분포를 얻을 수 있었다. 반사압축파에 의해 생성된 고온 고압의 산소중에서의 고체입자의 점화지연시간을 측정 하므로써 기체유동이 존재하는 입사압축파실험에서의 점화지연시간과 비교하여 기체유 동이 고체 미립자의 점화에 미치는 영향을 알아볼 수 있었고 반사압축파에 의한 점화 상태 조건하에서도 표면 점화모델이 성립하는지를 고찰해 보았다.

• 한국산업보건학회지
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• 제29권4호
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• pp.590-602
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• 2019

Objectives: This study was conducted to prevent asphyxiation of firefighters during confined space rescue. The specific purpose was to identify the magnitude of the problem, identify the cause of the accidents, and suggest measures to ensure safety of confined space rescues. Methods: We collected data from National Fallen Firefighters Memorial, press releases, and other sources In order to identify the current situation of asphyxiation incidents among firefighters from 1945 to 2019. In addition, an incident investigation was conducted for each case, and the processes, causes, and control measures of the incidents were described as a narrative data entry. Results: Over the past 73 years, eight incidents involving firefighter in Korea have occurred. In these incidents, five firefighters were killed, and eight were injured. The confined spaces incidents occurred were water supply tanks, wastewater treatment tanks, pickling pits, septic tanks, and more. The causes were three cases of hydrogen sulfide poisoning, one of oxygen deficiency, one of carbon monoxide poisoning, and three unclassifiable asphyxiations. The people in need were all workers in various industries. Conclusions: The number of firefighters' deaths and injuries during rescues in confined spaces was severe and the risks have not been completely eliminated. By establishing and implementing a precise incident investigation system, according control measures should be initiatedin order to prevent a recurrence of the same type of disaster and reflected in the SOP. In particular, due to the high risk of occurrence at workplaces, cooperation between fire and rescue authority and relevant agencies such as the Ministry of Employment and Labor and the KOSHA should be strengthened.

• 한국해양공학회지
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• 제14권3호
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• pp.1-10
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• 2000

In order to effective manage the construction, disaster prevention plan and the harbor tranquility control, meteorological and sea-state characteristics around Cheju Island have been analyzed. Using results and damage examples of the port facilities under severe sea conditions, a reasonable construction control plan considering the regional characteristics of the sea-state and winds was proposed. That is, in northern part of Cheju Island, the construction work is affected mainly by the winter storms, while the typhoon mainly affects the southern part port facilities during summer to Autumn. Considering their typical characteristics, it is strongly suggested that the main construction work should be carried out during April to July in the northern part, and it should be made during October to next July in the southern part of the island. A permeable TTP mounded breakwater was constructed to protect severe waves as a temporal structure under the long-term development plan in Sogipo port. The transmission characteristics of the structure was discussed using the experimental results. The results show that the transmission coefficient $K_{t}$ is over 20% of incident waves, which cause many problems in the cargo handling in relation to harbor tranquility. In conclusion, this kind of permeable structure can be used only as a temporal structure for the disaster prevention under the construction process. It causes many problems in harbor tranquility if it is used as a permanent harbor structures.s.

• Journal of Trauma and Injury
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• 제25권4호
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• pp.278-282
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• 2012

An esophageal perforation following anterior cervical fusion is rare. Early development of an esophageal perforation after anterior cervical fusion is usually due to iatrogenic injury from retraction, injury associated with the original traumatic incident, improperly placed instruments or a bone graft. A 31-year-old man had a cervical dislocation and spinal cord injury because of severe cervical trauma after a traffic accident. He was quadriplegic and had no feeling below T4 dermatome. Anterior decompression of the cervical spine and anterior fusion with mesh with autobone were performed. An esophagocutaneous fistula occurred 7 days after anterior cervical surgery. A second anterior surgery was done because of pus drainage. The mesh was changed with an iliac bone graft, and the esophagocutaneous fistula site was primary repaired, but pus continued to drain. Conservative treatment, which consisted of wound drainage and intravenous administration of antibiotics, was tried, but was unsuccessful. After all, we removed the plate and screws, but did not removed the iliac bone graft, We closed the esophageal fistula, and transposed the sternocleidomastoid muscle flap to the interspace between the esophagus and the cervical spine. The wound to the esophagus was well repaired. In conclusion, precautionary measures are needed to avoid the complication, and adequate treatment is necessary to resolve those complications when they occur.

• 동의신경정신과학회지
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• 제14권2호
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• pp.191-198
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• 2003

Dissociative amnesia is a psychiatric disorder charicterized by a sudden loss of memory, but which has no organic disease or explanation, It usually occurs after severe psychosocial stress or traumatic experience. As for medical treatment, medicine, psychotherapy and hypnosis are used. This case describes a 35-years-old woman who developed amnesia and depression following severe troublesome events. So she suited without expression and appealed against headache, dizziness, chest discomfort and weakness. Psychoanalytic psychotherapy was enforced for three days with hypnosis. She expressed the felling over the incident which she dose not like, and canceled in the past. She became reconciled with the family and left the husband by the heart. Then she recovered memory completely and body condition also improved. Recovery and growth of self were helped using supportive expression in order to prevent a recurrence. The prognosis is good with complete recovery, and there was no relapse.

• Geomechanics and Engineering
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• 제16권2호
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• pp.177-185
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• 2018

The subsidence mechanism of ground surface is a complex phenomenon when multiple seam coal mining operations are carried out. Particularly, the coal mining beneath karstic formations causes a very special form of subsidence. The subsidence causes elasto-plastic deformation of the karstic layers and the collapse of cavities leads to dolinization and/or sinkhole formation. In this study, a sinkhole with a depth of 90 m and a width of 25 m formed in Gelik district within the coal-basin of Zonguldak (NW, Turkey) induced by multiple seam coal mining operations in the past has been presented as a case-history together with two-dimensional numerical simulations and InSAR monitoring. The computational results proved that the sinkhole was formed as a result of severe yielding in the close vicinity of the faults in contact with karstic formation due to multiple seam longwall mining at different levels.