• 한국화재소방학회논문지
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• 제21권2호
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• pp.54-63
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• 2007

콘크리트는 일반적으로 내화성능이 내재되어 있다고 여겨지나, 이것은 화재시 콘크리트의 낮은 열전달 특성으로 인해 폭렬이 일어나지 않는다는 것을 전제한 것이다. 그러나, 최근의 화재사고사례를 분석한 결과 콘크리트 폭렬이 구조물에 미치는 영향은 심대한 것을 알 수 있다. 따라서, 본 연구는 콘크리트 폭렬에 관한 선진 연구 성과의 이론적 고찰 및 실험결과의 분석 검토를 토대로 국내에 상대적으로 미흡한 화재시 콘크리트의 거동특성 및 폭렬현상을 체계적으로 규명하였다. 또한, 본 연구를 통해 화재조건에서의 성능 설계법을 제시할 수 있는 콘크리트 폭렬 기초연구자료를 제시하고자 한다. 폭발성 폭렬현상은 고온 영역 하에서 공극압력이 상승하게 되어 단면을 감싸는 인장응력보다 박리되고자 하는 압력이 커지게 되어 $200^{\circ}C{\sim}400^{\circ}C$에서 발생하게 된다. 폭렬에 직접적인 원인이 되는 요소는 수분함유량, 공극(수증기에 의한) 압력, 변형에 의한 응력변화(하중비), 가열비(화재강도) 등으로 할 수 있다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제11권2호
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• pp.782-795
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• 2019

Safety is always acritical focus of exploration of ocean resources, and it is well recognized that human factor is one of the major causes of accidents and breakdowns. Our research developed a dynamic human reliability assessment approach, Predicted Mean Vote-Cognitive Reliability and Error Analysis Method (PMV-CREAM), that is applicable to monitoring the cognitive reliability of oceanauts during deep-sea missions. Taking into account the difficult and variable operating environment of manned submersibles, this paper analyzed the cognitive actions of oceanauts during the various procedures required by deep-sea missions, and calculated the PMV index using human factors and dynamic environmental data. The Cognitive Failure Probabilities (CFP) were calculated using the extended CREAM approach. Finally, the CFP were corrected using the PMV index. This PMV-CREAM hybrid model can be utilized to avoid human error in deep-sea research, thereby preventing injury and loss of life during undersea work. This paper verified the method with "Jiaolong" manned submersible 7,000 m dive test. The"Jiaolong" oceanauts CR(Corrected CFP) is dynamic from 3.0615E-3 to 4.2948E-3, the CR caused by the environment is 1.2333E-3. The result shown the PMV-CREAM method could describe the dynamic human reliability of manned submersible caused by thermal environment.

• Nuclear Engineering and Technology
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• 제47권1호
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• pp.74-84
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• 2015

If a transient occurs in a nuclear power plant (NPP), operators will try to protect the NPP by estimating the kind of abnormality and mitigating it based on recommended procedures. Similarly, operators take actions based on severe accident management guidelines when there is the possibility of a severe accident occurrence in an NPP. In any such situation, information about the occurrence time of severe accident-related events can be very important to operators to set up severe accident management strategies. Therefore, support systems that can quickly provide this kind of information will be very useful when operators try to manage severe accidents. In this research, the occurrence times of several events that could happen during a severe accident were predicted using support vector machines with short time variations of plant status variables inputs. For the preliminary step, the break location and size of a loss of coolant accident (LOCA) were identified. Training and testing data sets were obtained using the MAAP5 code. The results show that the proposed algorithm can correctly classify the break location of the LOCA and can estimate the break size of the LOCA very accurately. In addition, the occurrence times of severe accident major events were predicted under various severe accident paths, with reasonable error. With these results, it is expected that it will be possible to apply the proposed algorithm to real NPPs because the algorithm uses only the early phase data after the reactor SCRAM, which can be obtained accurately for accident simulations.

• 서비스연구
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• 제1권1호
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• pp.103-111
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• 2011

모바일 컴퓨팅의 르네상스 시대를 이끌어가고 있는 스마트폰은 조만간 전 세계의 휴대폰 시장을 점령할 것으로 예상되고 있으며, 특히 안드로이드 플랫폼 기반 스마트폰에 대한 수요가 급격히 상승하고 있다. 이에 따라 스마트폰 사용자를 위한 다양한 애플리케이션 서비스 모듈이 개발되고 있으며, 이들이 서비스 혁신에 기여하고 있다. 한편 모바일 기능을 지원하는 LBS(즉 Location Based Service) 시스템에 대한 기술 지원 및 기술의 개방으로 이와 관련한 많은 애플리케이션이 등장하는 추세이다. 우리는 이 LBS 시스템으로 운전자에 대한 교통사고 발생시 위치 정보 전송을 중점적으로 활용하고, 또한 운전자에게 여러 편리성을 제공하기 위하여 Driver Manger 서비스 모듈을 연구하였다.

• 농촌의학ㆍ지역보건
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• 제23권2호
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• pp.215-227
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• 1998

To find health problems of Pohang city and to plan the activities to solve them in the situation of localization, the mortalities of the citizens in recent three years from 1994 to 1996 were analyzed from the notices and the certificates of death. The ratios of the notices with the certificates of death In the rural area of Pohang city were higher than those of whole country, the ratios of the urban area were lower than the respective ones, and the ratio differences between the rural and urban area were increasing. It may be that medical facilities are not within easy access of the rural inhabitants. especially in the rural south district with high population density. The proportional mortality indicators(PMI) were lower them those of whole country, much lower in male. So the health status of young aged males is relatively unsatisfactory. The urban inhabitants died in hospitals about two times more than the rural inhabitants and the differences were increasing. It may be that living and housing conditions and socio-cultural differences affected on the places of death. Because it is thought that death in hospitals will be growing at high speed, it is necessary to enlarge facilities fur funeral services. The age standardized mortalities were lower than those of whole country and age grouped mortalities were also the same. There were not any consistent and meaningful findings in the sex ratios of mortality according to the age groups or the calendar years. The mortalities by neoplasms and cardiovascular diseases according to the twenty one major causes of death were rapidly increased from the middle ages in both male and female. So it is important to plan the activities for early detection and health maintenance or promotion by behavior modifications. The leading causes of death were cardiovascular diseases, hypertensive diseases, and traffic accidents. And accidental drowning because of coastal area, liver diseases in male, and low respiratory tract diseases in female were the leading causes of death in part of age groups.

• 한국초등과학교육학회지:초등과학교육
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• 제27권2호
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• pp.117-133
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• 2008

The purpose of this study was to investigate the elementary students' views about lab-based science learning. For the purpose of this study, semi-structured interviews were conducted with thirty sixth grade students in 12 classes from two elementary schools located in Daegu City. The interview contents consisted of three major categories. The first category was related to attitude toward science lab, the second was related to lab-based science learning which had four sub-categories; recognizing lesson object, planning experiment, performing experiment, drawing conclusion in lab-based science learning in which the students had ordinary have views and expectations, and the last category was related to students' difficulties and something need to be improved in lab-based science learning. In-depth interviews were performed individually and the interviews were recorded. From the interviews, we found that students, in first category, do like lab-activities more than lectures or instruction-based activities in textbook. Students, in second category, wanted generally more discussion for their own activities rather than teacher's instruction and they wanted teacher' mediation conflicts within small groups and comments for students' experiment results. In the last, most of students had fears for some dangerous reagents and accidents. Based on the results, the study suggested that teacher need to give their students to autonomous discussion opportunities to design and interpret data through teacher' guided questions in inquiry steps, to produce some intimate atmosphere for active interaction in small groups, and to teach the safety education on some dangerous reagents.

• 한국경제지리학회지
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• 제13권4호
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• pp.681-696
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• 2010

본 연구는 부동산 개발사업 각 단계별로 발생 가능한 위험요인의 중요도를 평가하고, 이에 대한 관리방안을 제시하는데 목적이 있다. 이를 위해 부동산 개발사업에 영향을 미칠 것으로 예상되는 단계별 위험요인을 선행연구를 통해 사전적으로 도출한 다음, 부동산 개발사업 전문가들을 대상으로 설문조사를 실시하여, 단계별 위험요인들의 중요도를 AHP 기법을 이용하여 평가했다. 본 연구결과를 요약하면 다음과 같다. 첫째, 부동산 개발사업의 대분류별 위험요인을 분석한 결과, 개발 전 단계에서는 기획 위험, 개발준비 단계에서는 개발사업 인허가 위험, 개발 단계에서는 현금흐름 위험이 가장 중요한 것으로 평가되었다. 둘째, 부동산 개발사업의 소분류별 위험요인을 분석한 결과, 개발 전 단계에서는 소비자 선호도의 변화, 개발준비 단계에서는 계약 및 인허가 관련업무, 개발 단계에서는 시행사 및 건설사의 부도, 관리 및 운영 단계에서는 사고 및 재해의 발생에 의한 시설보상이 가장 중요한 위험요인으로 평가되었다. 셋째, 이러한 위험요인의 중요도 평가결과에 따라 단계별 위험관리 방안을 제시했다.

• Advances in pediatric surgery
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• 제16권1호
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• pp.25-31
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• 2010

Hickman catheters are tunneled central venous catheters used for long-term venous access in children with malignancies. The appropriate management for various kinds of catheter related complications has become a major issue. We retrospectively analyzed the clinical, demographic, and surgical characteristics in 154 pediatric hemato-oncology patients who underwent Hickman catheter insertion between January 2005 and December 2009. There were 92 boys and 62 girls. The mean age at surgery was $7.6{\pm}5.1$ years old. The mean operation time was $67.4{\pm}21.3$ minutes and C-arm fluoroscopy was used in 47(30.5 %). The causes of Hickman catheter removal were termination of use in 82 (57.3 %), catheter related bloodstream infection in 44(30.8 %), mechanical malfunction in 11(7.7 %), and accidents in 6(4.2 %). Univariate and multivariate analysis for associated factors with catheter related bloodstream infection showed that there were no statistically significant associated factors with catheter related infection complications. All cases except two showed clinical improvement with catheter removal and relevant antibiotics treatment. The mean catheter maintenance period in patients of catheter removal without complications was $214.9{\pm}140.2$ days. And, The mean catheter maintenance period in patients of late catheter related bloodstream infection was $198.0{\pm}116.0$ days. These data suggest that it is important to remove Hickman catheter as soon as possible after the termination of use. When symptoms and signs of complications were noticed, prompt diagnostic approach and management can lead to clinical improvements.

• 융합보안논문지
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• 제15권7호
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• pp.39-45
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• 2015

최근 기업이 보유한 산업기밀은 영업비밀보호법, 산업기술유출방지법 등 다양한 산업보안 관련 법률에 의해 보호 받고 있다. 그러나 그러한 보호에도 불구하고 산업기밀의 침해 및 유출사고는 해마다 증가하고 있다. 한국산업기술보호협회의 조사에 따르면 산업기밀 유출 예상 피해액은 연평균 "50조 원"으로 추정되며 이는 중소기업 4,700여 개의 연 매출액과 맞먹는 금액이다. 이처럼 산업기밀 유출은 국가와 기업의 경쟁력은 물론이고 경제적으로도 심각한 피해를 초래한다. 하지만 산업기밀 유출범죄에 대한 투자와 노력은 피해규모에 비해 한 없이 부족한 수준이며 일부 대기업을 제외한 대부분의 기업들이 산업기밀 유출보안을 위한 별도의 조직, 인력, 예산이 없어 산업기밀 유출에 대한 대응체계가 부족한 것이 현실이다. 본 논문은 국내외 산업기밀 유출범죄 분석을 통하여 산업기밀 유출에 따른 피해실태를 파악하고 발생원인, 유출경로 등 다양한 분류체계를 통하여 산업기밀 유출범죄에 대한 전반적인 흐름을 파악하여 관련 연구에 대한 기초자료가 될 것으로 기대한다.

• 한국정보통신학회논문지
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• 제18권6호
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• pp.1429-1434
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• 2014

현재 자동차 급발진 사고가 급증하고 있다. 아직도 정확한 자동차 급발진 원인을 찾지 못해 아무것도 모르는 운전자가 급발진 사고에 대한 아픔을 가지고 모든 책임을 감당하고 있다. 사용자가 이런 문제를 제조사에 제기할 경우 자동차에 설치된 EDR(Event Data Recorder)을 회수해서 제조사 자체적으로 분석해서 알려주지만, 대부분 자동차에서는 문제가 없다고 일축한다. 이런 상황에서 급발진 사고에서 운전자의 신변을 보호를 위한 기술이 개발이 필요하다. 본 논문에서는 자동차 급발진 사고의 여러 원인 중 유력하게 추정되는 스로틀밸브의 문제에서 운전자의 신변을 보호하기 위해 관련 데이터를 추가적으로 수집하는 블랙박스 시스템을 개발하였다.