• Smart Structures and Systems
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• 제29권4호
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• pp.589-598
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• 2022

Timber structures are susceptible to structural damages caused by variations in moisture content (MC), inducing severe durability deterioration and safety issues. Therefore, it is of great significance to detect MC levels in timber structures. Compared to current methods for timber MC detection, which are time-consuming and require bulky equipment deployment, Lead Zirconate Titanate (PZT)-enabled stress wave sensing combined with statistic machine learning classification proposed in this paper show the advantage of the portable device and ease of operation. First, stress wave signals from different MC cases are excited and received by PZT sensors through active sensing. Subsequently, two non-baseline features are extracted from these stress wave signals. Finally, these features are fed to a statistic machine learning classifier (i.e., naïve Bayesian classification) to achieve MC detection of timber structures. Numerical simulations validate the feasibility of PZT-enabled sensing to perceive MC variations. Tests referring to five MC cases are conducted to verify the effectiveness of the proposed method. Results present high accuracy for timber MC detection, showing a great potential to conduct rapid and long-term monitoring of the MC level of timber structures in future field applications.

• 대한안전경영과학회지
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• 제25권2호
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• pp.9-15
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• 2023

The Severe Disaster Punishment Act had recently been established in order to promote safety and health (OSH) management system for severe accident prevention. OSH management system is primarily designed based on risk assessments; however, companies in industries have been experiencing difficulties in hazard identification and selecting proper measures for risk assessments and accident prevention. This study intended to introduce an accident analysis method based on epidemiological model in finding hazard and preventive measures. The accident analysis method employed in this study was proposed by the U.S. Department of Energy. To demonstrate the effectiveness of the accident analysis method, this study applied it to two accident cases occurred in construction and manufacturing industries. The application process and results of this study can be utilized in improving OSH management system and preventing severe accidents.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2007년도 정기학술발표대회 논문집
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• pp.450-454
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• 2007

최근 건설업의 대형화, 복잡화됨에 따라 안전사고가 증가하고 있다. 특히, 건설장비에 의한 사고 발생수가 증가하고 있다. 이런 사고의 예방을 위해서는 발생원인을 분석할 필요가 있다. 본 논문은 한국산업안전공단의 건설재해사례를 통해 안전사고 원인을 분석한다. 연구의 범위는 굴삭기 장비로 한정하였다. 본 연구의 결과를 요약하면 다음과 같다. 1) 굴삭기 재해 발생 형태는 협착${\cdot}$감김, 낙하${\cdot}$비래, 충돌${\cdot}$접촉 순으로 분석되었따. 2) 재해원인은 작업반경 내에 근로자출입, 주용도 이외의 용도로 사용함, 작업시작 전 저멈불량${\cdot}$ 작업방법불량 순으로 분석되었다. 이 연구결과는 차후 연구의 기초를 정립하고, 안전사고를 줄이는 기대효과를 가질 것이다.

• 한국안전학회지
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• 제35권5호
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• pp.106-114
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• 2020

The two major trends that have emerged in recent years in relation to disaster recovery and recovery are 'regional infrastructure', 'regional leadership' and 'community recovery'. In the former case, it is to avoid disaster recovery and recovery by using external personnel and resources, and to maximize the resources in the area under the initiative of the residents of the affected area. And through this process, it is to prepare a new growth engine for disaster-affected areas. In addition, the latter expands disaster recovery targets to the general population living in affected areas and is not limited to victims. Through this, we can expect to recover the 'community' beyond the individual's recovery. In the Ansan of Gyeonggi-do, where many families of 'Sewolho' live, and in the Heunghae-eup of Pohang, Gyeongbuk-do, where the damage was severe, projects are underway to restore communities. And In these areas local activists and civic groups are actively utilized to efforts are being made to increase efficiency. Nevertheless, in the case of the community recovery program being promoted in Korea, there are limitations that it can be promoted only on the basis of special laws and that participation of various actors is necessary. This study intends to propose the limitations of current projects and ways to solve them by analyzing domestic and foreign cases related to the community recovery program for disaster-affected communities using local resources. we suggest two way. One is the relaxation of the national dependence of the community recovery program, and the other is to expand the area of disaster relief through.

• Nuclear Engineering and Technology
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• 제55권8호
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• pp.3102-3113
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• 2023

Following the Fukushima nuclear disaster, the simulation of accidents in the spent fuel pool has become more noticeable. Despite the low amount of decay heat power, the consequences of the accidents in a spent fuel pool (SFP) can be severe due to the high content of long-lived radionuclides and lack of protection by the pressure vessel. In this study, the loss-of-cooling accident (LOFA) for the VVER-1000/V446 spent fuel pool is simulated by employing RELAP5 and MELCOR 1.8.6 as the best estimate and severe accident analysis codes, respectively. For two cases with different total power levels, decay heat of spent fuels is calculated by ORIGEN-II code. For modeling SFP of a VVER-1000, a qualified nodalizations are considered in both codes. During LOFA in SFP, the key sequences such as heating up of the pool water, boiling and reducing the water level, uncovering the spent fuels, increasing the temperature of the spent fuels, starting oxidation process (generating Hydrogen and extra power), the onset of fuel melting, and finally releasing radionuclides are studied for both cases. The obtained results show a reasonable consistency between the RELAP5 and MELCOR codes, especially before starting the oxidation process.

• 한국건축시공학회지
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• 제8권3호
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• pp.127-133
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• 2008

Safety accident resulting from construction projects getting larger and complex day by day has occurred more often than ever. Particularly, the accident caused by construction equipment, among others, has been on the rise. To prevent such accidents, it's necessary to come up with the measures for reducing the accident. In this study, the cause of safety accidents was analyzed, reviewing the cases of safety accident maintained by Korea Occupational Safety & Health Agency, and the measures for reducing the accident was suggested with computerized safety checklist. The scope of study was limited to excavator, and the result is summarized as below. 1) Investigation was conducted to identify the cases of accident by excavator with the primary causes. 2) Reduction measures were suggested by category of cause of excavator-caused accident. 3) Checklist to prevent the safety accident, which was based on primary causes, was suggested. 4) The measures to stir up safety consciousness and monitor the safety were suggested, making use of computerized system. This study is expected to lay the foundation for further study in future as well as make a great commitment to reducing the safety accident.

• 대한지리학회지
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• 제43권6호
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• pp.858-872
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• 2008

본 연구는 사료를 기초로 조선시대 제주도의 기상재해에 대하여 살펴보고, 정부와 제주민들은 이에 어떻게 대응했는지를 분석하였다. 조선시대 제주도의 기상 특이일 기록 건수는 17세기가 가장 많았고, 18세기, 16세기, 15세기, 19세기 순으로 나타났다. 기상재해의 유형별로는 풍해가 가장 많았고, 수해, 한해(旱害), 설동해 순으로 나타났다. 지역별로는 제주목이 풍해와 수해가 많았고, 대정현은 한해가 많았다. 기상재해가 발생하면 기근으로 이어지는 것이 상례였다. 정부에서는 한반도의 곡식을 제주도로 이전하여 백성을 구제하였으며, 이를 위해 갈두진창, 나리포창, 제민창을 설치하였다. 또한 제주도 백성을 평안도 등 한반도로 이주시켜 만성적인 기근을 해결하고자 했다. 이상 기후에 대응하여 제주도 농민들은 답전, 바령, 복토, 방풍 등의 농법을 행하였고, 해민들은 환전, 석력 선적 등의 항해술을 행하였다.

• 한국방재안전학회논문집
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• 제15권3호
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• pp.57-66
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• 2022

고용노동부 공문(최근 건설업 사망사고 발생 현황 안내 및 안전관리 철저 당부, 2022.4.4.)에 따르면, 중대재해처벌법 시행(2022.1.27.) 이후 2022.3.31.까지 공사금액 50억원 이상 건설공사에서 17건의 사망사고가 발생하여 18명이 사망했다. 공사규모로 보면 50억~120억원 7건, 120억~800억원 5건, 800억원이상 5건이 발생했다. 사망사고 발생원인은 떨어짐 9건(50%), 맞음 5건(28%), 무너짐 2건(11%), 끼임 1건(5%), 익사 1건(5%)으로 조사됐다. 사망사고의 대부분을 차지하는 떨어짐과 맞음으로 인한 사망사고를 줄이기 위해서는 안전시설물을 강화할 필요가 있으며, 추락방지망·개구부·안전난간이 완벽하게 설치되면 대부분의 떨어짐과 맞음 사고는 예방 할 수 있다. 따라서 본 고에서는 소규모 공동주택인 도시형생활주택신축현장의 떨어짐과 맞음 사고를 예방하기 위해서 안전시설물 개선을 통한 특허기술 개발과 활용 사례를 제시하고자 한다.

• 생태와환경
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• 제41권4호
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• pp.423-430
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• 2008

As of September 2008,45 Automatic Water Quality Monitoring Systems (AWQMS) have been installed at different sites on the 4 rivers to detect early the presence of pollutants in water and to issue an alarm. We count the number of issuing alarms by AWQMS, however, we will find the alarm has hardly been issued. The reasons for the scarcity of alarm issue are extensively being examined. The National Institute of Environmental Research attributes wrong alarm criteria for each AWQMS station to one the reasons. In this study, a suggestion has been made to modify the current alarm criteria to correspond with characteristics of river water quality. The current system with only two criteria (low and high) should be replaced as four-criteria systems (low, medium, high, and severe) based on cases of other advanced countries and stream conditions of Korea. The highest value of data collected for 5 years was suggested as the alarm criteria for each parameter. Meanwhile the alarm criteria for VOCs, phenol and heavy metals were established as same as drinking water quality criteria.

• Environmental Analysis Health and Toxicology
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• 제31권
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• pp.25.1-25.9
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• 2016

Objectives After the initial investigations by the Korea Centers for Disease Control in 2011, over 1000 suspicious cases of humidifier disinfectant (HD) victims were subsequently reported by 2015, and numbers are still increasing dramatically in 2016 in the midst of the prosecutors' office investigation. This study attempts to summarize the current understandings of the related health effects of HD based upon a systemic review of published epidemiologic studies and toxicology investigations. Methods Published studies of HDs were searched through PubMed and TOXLINE under the search words 'humidifier disinfectant,' and related reports were identified from the references and published report list of regulatory agencies including the Korean National Institute of Environmental Research, US Environmental Protection Agency, and EU European Chemicals Agency. Results Case reports and epidemiologic studies have reported the clinical features of severe forms of HD lung damage, together with epidemiologic findings of seasonal occurrence and demographic variations, including the heightened susceptibility of young children. Toxicological studies have reported inhalation toxicities together with positive findings of in vitro genotoxicity studies. Conclusions This study examined unsolved issues based on cases of upper respiratory diseases and diseases of other organs, including cancers, among suspected victims of HDs. These issues should be clarified in future research for the management and prevention of health effects from HDs and chemicals of other related household products.