• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
• /
• pp.1356-1359
• /
• 1996

The paper studies design of a decentralized supervisory controller with 2-level hierarchical structure for complex discrete event systems. Hierarchical structure with strict output-control-consistency(SOCC) gives a more abstract model for high-level control. The decentralized controller for a simple and abstract high-level system is designed more easily if the decentralized supervisory control problem in 2-level hierarchical structure systems(DSCP2) is solvable.

• Nuclear Engineering and Technology
• /
• 제53권2호
• /
• pp.498-508
• /
• 2021

Micro reactors are increasingly being considered for utilization as distributed power sources. Hence, the probabilistic safety assessment (PSA) of a direct supercritical-CO₂-cooled fast reactor, called micro modular reactor (MMR), was performed in this study; this reactor was developed using innovative design concepts. It adopted a modular design and passive safety systems to minimize site constraints. As the MMR is in its conceptual design phase, design weaknesses and valuable safety insights could be identified during PSA. Level 1 internal event PSA was carried out involving literature survey, system characterization, identification of initiating events, transient analyses, development of event trees and fault trees, and quantification. The initiating events and scenarios significantly contributing to core damage frequency (CDF) were determined to identify design weaknesses in MMR. The most significant initiating event category contributing to CDF was the transients with the power conversion system initially available category, owing to its relatively high occurrence frequency. Further, an importance analysis revealed that the safety of MMR can be significantly improved by improving the reliability of reactor trip and passive decay heat removal system operation. The findings presented in this paper are expected to contribute toward future applications of PSA for assessing unconventional nuclear reactors in their conceptual design phases.

• Nuclear Engineering and Technology
• /
• 제55권11호
• /
• pp.4083-4095
• /
• 2023

Currently, various research institutes in Korea are conducting research to develop a safety case for deep geological repository for high-level radioactive waste (HLW). In the past, low and intermediate-level waste (LILW) was approved by a regulatory body by performing a post-closure safety assessment, but HLW has different disposal characteristics and safety objectives are different. Therefore, in the case of HLW, safety assessment should be performed based on these changed conditions, and specific procedures are also under development. In this paper, the regulatory status of prior research institutes, feature, event and process (FEP) and scenario development cases were investigated for well-organized FEP and scenario development methodologies. In addition, through the results of these surveys, the requirements and procedures necessary for the FEP and scenario development stage during the safety assessment of repository for HLW were presented. These review results are expected to be used to identify the overall status of previous studies in conducting post-closure risk assessment for HLW repository, starting with identifying regulatory requirements, the most basic element.

• International Journal of Advanced Culture Technology
• /
• 제11권2호
• /
• pp.191-195
• /
• 2023

An X-event is an event that is difficult to predict and unlikely to occur, but if it occurs, it has a very large ripple effect, such as loss of life, property, territory, and emotional turmoil. Extreme events are unlikely to occur, but they can happen someday, and if they do, they have a great impact on society as a whole, so they must be prepared to minimize the impact and impact. For this purpose, we collected opinions from low-level experts at the Korea Army Research Center for Future & Innovation and the Army College on extreme events that can trigger the near future (10 years) in the field of high-tech science and technology, which is currently developing rapidly after the 4th Industrial Revolution. The researchers intend to synthesize and analyze this data to derive implications and provide a response direction to alleviate the ultra-uncertainty of extreme events and provide a cornerstone for crisis management strategies for the occurrence of serial and simultaneous extreme events.

• International Journal of Naval Architecture and Ocean Engineering
• /
• 제4권3호
• /
• pp.211-227
• /
• 2012

To implement a combined discrete event and discrete time simulation such as submarine diving simulation in a distributed environment, e.g., in the High Level Architecture (HLA)/Run-Time Infrastructure (RTI), a HLA interface, which can easily connect combined models with the HLA/RTI, was developed in this study. To verify the function and performance of the HLA interface, it was applied to the submarine dive scenario in a distributed environment, and the distributed simulation shows the same results as the stand-alone simulation. Finally, by adding a visualization model to the simulation and by editing this model, we can confirm that the HLA interface can provide user-friendly functions such as adding new model and editing a model.

• 한국군사과학기술학회지
• /
• 제9권3호
• /
• pp.25-32
• /
• 2006

Weapon systems composed of several subsystems execute various engagement missions in distributed combat environments in cooperation with a large number of subordinate/adjacent weapon systems as well as higher echelons through tactical data links. Such distributed weapon systems require distributed real-time simulation test beds to integrate and test their operational software, analyze their performance and effects of cooperated engagement, and validate their requirement specifications. These demands present significant challenges in terms of real-time constraints, time synchronization, complexity and development cost of an engagement simulation test bed, thus necessitate the use of high-performance distributed real-time simulation architectures, and modeling and simulation techniques. In this paper, in order to meet these demands, we presented a distributed real-time simulation system based on High Level Architecture(HLA) and Discrete Event System Specification(DEVS). We validated its performance by using it as a test bed for developing the Engagement Control System(ECS) of a surface-to-air missile system. The proposed technique can be employed to design a prototype or model of engagement-level distributed real-time simulation systems.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2004년도 춘계종합학술대회
• /
• pp.651-654
• /
• 2004

본 연구에서는 HDL에서 블록 사이, 프로세스문장, 또는 일을 할당하는 순서를 조절하는 상위레벨 사건을 하위레벨 사건과 비교하여 정의하며, 상위레벨 사건은 자원충돌과 프로토콜 또는 사양의존 충돌로 구성된다는 것을 보여준다. 그리고 상위레벨 사건을 검출하기 위하여 2가지 검출방법이 제안된다.

• 한국심리학회지 : 문화 및 사회문제
• /
• 제19권3호
• /
• pp.319-341
• /
• 2013

본 연구는 외상 유형이 외상후성장 및 지혜에 영향을 미치는 경로모형에서 사회적 지지와 대처의 매개효과를 검증하였다. 이를 위해 247명의 성인자료를 대상으로 외상경험질문지, 스트레스 대처 반응 검사, 사회적 지지척도, 외상후성장 척도, 초월적 지혜척도를 실시하였다. 먼저, 두 외상 유형 집단인 대인외상 집단과 비대인외상 집단을 비교하여 외상후성장과 외상 정도, 사회적 지지, 대처, 지혜의 차이가 나타나는지 확인하였다. 그 결과, 비대인외상집단의 사회적 지지, 긍정적 대처, 외상후성장 및 지혜가 더 높게 나타났으며, 대인외상집단의 외상 정도, 회피적 대처가 더 높게 나타났다. 둘째, 외상 유형이 외상후성장 및 지혜에 영향을 미치는 모형을 경로분석으로 검증하였다. 그 결과, 외상 유형이 사회적 지지, 긍정적 대처, 외상후성장을 매개로 지혜에 영향을 주었고, 이 과정에서 사회적 지지, 긍정적 대처, 외상후성장의 매개효과가 검증되었다. 그러나 외상 유형에서 긍정적 대처로 가는 경로와 사회적 지지에서 회피적 대처로 가는 경로는 유의하지 않았다. 또한 회피적 대처의 매개효과는 검증되지 않았다. 결과를 종합하면, 비대인외상 유형이며, 사회적 지지가 높고, 긍정적 대처를 사용할수록 외상후성장이 높고 지혜가 발달한다는 것을 의미한다. 마지막으로 연구의 의의 및 외상에 대한 개입방안, 본 연구의 제한점 및 후속연구에 대해 논의하였다.

• 대한토목학회논문집
• /
• 제31권3B호
• /
• pp.265-276
• /
• 2011

한반도와 제주를 포함한 전국의 강우 자료와 국가지하수위 관측소에 관측된 지하수위 관측 자료를 수집하였다. 강우와 지하수위의 관계를 분석한 후 강우자료를 이용하여 이동평균을 취한 후 지하수위와의 상관관계를 분석하였다. 또한 유역평균 일최대침투량인 한계침투량을 고려한 후, 강우이동평균과 지하수위간의 상관계수를 산정하였다. 한계침투량 고려시 상관계수가 0.6 이상인 곳을 최종적으로 선정하였고, 선정된 지역의 공통점과 지역 특성에 따른 차이점 등을 비교 분석하였다. 총 26개 지역이 선정되었고 행정구역별로 경기도가 4개소, 강원도가 4개소, 충청도가 5개소, 전라도가 3개소, 경상도가 9개소, 제주도가 1개소이다. 상관계수가 높을수록 강우사상 발생에 따른 지하수위 변동은 뚜렷하게 나타났으며, 강우와 상관없는 요인에 의한 지하수위의 변동이 거의 없는 것으로 나타났다. 본 연구를 토대로 강우 예측 시나리오를 활용한다면 상관계수가 높은 지역에서 지하수위 또한 예측이 가능할 것으로 기대된다.

• 한국응급구조학회지
• /
• 제12권3호
• /
• pp.5-15
• /
• 2008

Purpose : This study is a descriptive research to provide basic factors of posttraumatic stress in Firefighters. This study was carried out to develop the effective program for the fire fighters to cope with the posttraumatic stress following the disasters. Methods : The questionnaires were collected among fire fighters who serviced in K and I community from April 1 to June 30 in 2008. Total 304 questionnaires were analyzed by SPSS WIN program for descriptive statistics, Pearson's correlation coefficient and t-test. Results : 1. 48.0% of 300 fire fighters were at the age of 31-40, and 42.3% were under 30. 2. Work burden had a significant difference of 2.30 in low-risk group, 2.60 in high-risk group(t-value=-3.85, p=0.00). However, life event had no significant difference 0.79 event in low-risk group, 1.41 event in high-risk group(t-value=-2.27, p=0.24). 3. Concerning posttraumatic stress factors, there was positive correlation between mobilization impact level r=0.38(P<0.01), work burden r=0.38(p<0.01), and life event r=0.27(p<0.01). 4. According to the Symptom Check List-Revised(SCL-90-R), somatization had a significant differences(t-value=5.46, p=0.00), obsessive-compulsive(t-value=7.16, p=0.00), interpersonal sensitivity(t-value=6.15, p=0.00), depression(t-value=6.62, p=0.00), anxiety (t-value=7.33, p=0.00), hostility(t-value=5.94, p=0.00), phobia anxiety(t-value=6.85, p=0.00), paranoid ideation(t-value=5.55, p=0.00), psychotism(t-value=6.52, p=0.00) in low-risk and high-risk group. Conclusion : As a consequence, mobilization impact, work burden, and life event were the influential factors on posttraumatic stress. Also, high-risk group revealed significantly higher score on all 9 scales. The information obtained from surveys made recommendation to develop the intervention of stress management to control mobilization impact and posttraumatic stress.