• 동력기계공학회지
• /
• 제10권1호
• /
• pp.90-95
• /
• 2006

Pneumatic control systems have been mainly used as a high speed operating system. Therefore, state change of air in a control volume was assumed to be adiabatic change and, pneumatic control systems have been analyzed by using this assumption. Especially, when absolute value of pressure change in the control volume is small, there is a tendency to neglect effect of temperature change on pneumatic control system because temperature change owing to pressure change is small. In this study, an effect of temperature change of air on the decompression control process was analyzed by considering change of mass flow rate, and heat transfer characteristics between air in the chamber and the chamber wall. As a result, this study could confirm that a slight temperature change of the air in the pneumatic pressure control system can influence on the dynamic characteristics of pressure response, and pressure control performance.

• 건축역사연구
• /
• 제32권3호
• /
• pp.39-51
• /
• 2023

This study aims to develop a cultural heritage curriculum for climate change and present educational directions for cultural heritage and climate change impact in the future. In this study, the role and necessity of cultural heritage education for climate change were first discussed based on previous studies on climate change and cultural heritage. Next, the current status analysis of educational cases related to climate change and cultural heritage was conducted based on educational manuals, curriculum, and heritage competency systems associated with climate change. Finally, we propose a plan to develop a curriculum to cope with climate change and cultural heritage for graduate students in higher education institutions based on the four components of developing a curriculum. In future studies, we intend to propose guidelines for designing educational manuals and specific curricula for each educational target to cope with the climate change of cultural heritage presented in this study.

• 한국환경교육학회지:환경교육
• /
• 제22권2호
• /
• pp.1-22
• /
• 2009

Even though climate change is visibly proceeding and public concern about climate change is increasing both nationally and internationally, teenagers' and students' perception of climate change is relatively low in Korea. Since climate change is a problem with long-term effects, it is young people including children and juveniles of the current generation and future generations who are more affected by climate change. They are the most interested party who should know why climate change happens, what kind of impacts will be given, and how to respond to the problem. Based on the aforementioned concern, this study aims to explore the extent and contents of school education with regard to climate change in Korea as well as in other advanced countries and to provide policy suggestions. This study finds that school climate change education requires consideration of multiple aspects including reorganization of school curriculum, revitalization of related programs by school, expansion of teachers' training chances, in which multiple institutions such as the Ministry of Environment, the Ministry of Education, Science and Technology, Offices of Education are related and, consequently, the activation of climate change education program is by no means simple. Therefore, for effective climate change education in schools, cooperation and coordination of related institutions are essential, along with development of diverse school education curriculums and programs and training programs for teachers.

• 응용통계연구
• /
• 제17권2호
• /
• pp.281-301
• /
• 2004

본 논문에서는 일변량 정규분포를 따르는 확률변수의 관측치열에 대한 변화점 문제(change point problem)를 고찰한다. 변화점의 존재유무, 그리고 만일 변화점이 존재한다면 어떠한 유형으로 발생했는지 즉, 변화점 발생 이후로 평균만 변화, 분산만 변화, 또는 평균과 분산 모두가 변화했는지를 밝힌다. 가능한 여러 유형의 변화모형들 가운데 최적의 모형을 선택하기 위해 베이지안 모형선택 기법을 이용하고, 선택된 모형에 내재된 모수를 추정 하기 위해 메트로폴리스-혜스팅스 알고리 즘을 포함한 깁스샘플링 을 이용한다. 이러한 방법론은 모의실험을 통해 검토되고, 또한 서울지역의 겨울철 평균기온 자료에 적용된다.

• 한국환경복원기술학회지
• /
• 제24권6호
• /
• pp.97-107
• /
• 2021

Abnormal climate caused by climate change causes enormous social and economic damage. And such damage and its impact may vary depending on the location and regional characteristics of the region and the social and economic conditions of local residents. Therefore, it is necessary to continuously monitor whether there are indicators that are weaker than other regions among the detailed indicators that constitute the risk, exposure and vulnerability of climate change risk. In this study, the concept of climate change risk was used for heatwave to determine regional inequality of climate change risk. In other words, it was judged that inequality in climate change risk occurred in regions with high risk but high exposure and low vulnerability compared to other regions. As a result of the analysis, it was found that 13 local governments in Korea experienced regional inequality in climate change risk. In order to resolve regional inequality in climate change risks, the current status of regional inequality in climate change should be checked based on the analysis proposed in this study, there is a need for an evaluation and monitoring system that can provide appropriate feedback on areas where inequality has occurred. This continuous evaluation and monitoring-based feedback system is expected to be of great help in resolving regional inequality in climate change risks.

• 국제학술발표논문집
• /
• The 3th International Conference on Construction Engineering and Project Management
• /
• pp.1283-1287
• /
• 2009

The Korean government implemented 259 road projects from 2004 to 2007, valued at $18.4 billion. Change orders of these road projects occurred 8,973 times and, subsequently, caused significant increases in the cost of the projects, approximately up to $4.2 billion (22.8% of the initial budget). These significant problems of huge change orders require a more workable control system for budget management whereas the effectiveness of the government's control is still not satisfied. However, previous approaches and studies mostly limited their analyses to simply classifying the causes of the change orders. This paper investigates the real frequency and cost impacts incurred by each cause of a change order, primarily based on 218 road projects in Korea. The paper then identifies the attributes of change orders through a survey of 204 project participants in that those sources were inevitable or avoided if properly managed. The causes of the change orders are further analyzed with analysis of variance (ANOVA) in connection with contract volume, bid award rate, the contractor's capacity to perform, and the design company's capacity. This study found that if the contract volume is smaller, then the possibility of change orders is higher. Interestingly, if the bid award rate is less than 67.5%, it signifies the highest rate of change orders. In addition, the contractors whose construction ability is assessed as the top-ranked group showed the lowest change order rates. With these results, this paper provides the preventive guidelines for reducing the likelihood of change orders.

• 성인간호학회지
• /
• 제18권3호
• /
• pp.345-356
• /
• 2006

Purpose: This study was conducted to compare the process of change, decisional balance, and self-efficacy according to the stages of change of exercise on the basis of the Transtheoretical Model in order to investigate factors associated with the change of exercise in adult diabetic patients. Method: Data were collected from January to April 2005. The subjects were 160 patients in the G university hospital and public health center in J city. Results: The entire process of change showed the significant difference depending on the stage of change(F=20.007, p=.000). For each process of change, the Consciousness Raising(F=14.602, p=.000), Dramatic Relief(F=7.751, p=.000), Environmental Re-evaluation(F=11.843, p=.000), Self Re-evaluation(F=16.035, p=.000), Social Liberation(F=10.968, p=.000), Counter-conditioning (F=24.090, p=.000), Helping Relationships(F= 7.625, p=.000), Reinforcement Management(F= 16.693, p=.000), Self Liberation(F=11.990, p= .000) and Stimulus Control(F=4.020, p=.002) demonstrated significant differences depending on the stages of change of exercise. For the decisional balance, the Pros showed the significant difference depending on the stage of change(F=14.121, p=.000). For the self efficacy showed significant difference depending on the stage of change(F=17.137, p=.000). Conclusion: In order to proceed the stage of change of exercise in patients with Diabetes Mellitus, intensive use of a specific process of change, a stage of change matching is needed.

• 한국전자거래학회지
• /
• 제12권3호
• /
• pp.33-47
• /
• 2007

소프트웨어 개발 초기에 모든 요구사항을 정의하는 것은 불가능하기 때문에 요구사항은 소프트웨어 개발이 진행되는 동안에 지속적으로 변경된다. 이러한 요구사항 변경은 개발자가 소프트웨어 구조나 행위를 완벽하게 이해하지 못하거나 변경에 따라 영향을 받는 모든 부분을 식별할 수 없을 경우 많은 오류를 야기 시킨다. 그러므로, 조직의 비즈니스에 공헌하면서 비용 효과적으로 적절히 처리되기 위하여 요구사항은 관리되고 평가되어야한다. 본 논문은 가치분석을 통하여 생성된 휘처 기반의 요구사항추적 링크를 근간으로 하는 요구사항변경 관리 기법을 제안한다. 이는 사용자 요구사항과 산출물간의 연결을 분석하기 위하여 휘처를 중간 매개체로 활용한 추적 링크를 이용한다. 그리고, 요구사항 변경 요청을 휘처 단위로 상세화하기 위한 변경 트리 모델을 정의하고 변경 관리가 수행되는 전체적인 프로세스를 제시한다. 또한, 요구사항 변경 관리 기법을 자산관리포탈시스템에 적용한 사례의 결과를 기술한다.

• 정보처리학회논문지:소프트웨어 및 데이터공학
• /
• 제3권2호
• /
• pp.65-72
• /
• 2014

변경 결합도는 두 요소들 사이의 향후 변경 연관성을 알려준다. 만약, 소스 파일들이 자주 함께 변경된다면, 그 소스 파일들의 변경 결합도는 높다고 볼 수 있으며, 나중에 다시 함께 변경될 확률이 높다. 일반적으로 소스 파일들 사이의 변경 결합도는 공통 변경 횟수에 기반하여 정의되었다. 그런데 연관성이 낮은 변경들이 일괄적으로 함께 커밋되는 경우, 즉 뒤얽힌 변경(tangled change)과 같은 경우들이 빈번히 발생한다. 따라서 함께 변경된 횟수만으로 소스 파일의 변경 결합도를 결정하는 것은 한계가 있다. 본 논문에서는 기존의 방법을 보완하기 위해, 소스 파일의 변경 시간뿐 아니라 소스 코드 변경 유형의 유사성을 함께 고려하는 것을 제안하였다. 이를 위하여, 우선 추출된 변경 유형 정보를 이용하여 변경 유형 빈도 벡터를 정의하고, 다음에 코사인 유사도 측정을 통해서 각 소스 파일 버전에서 적용된 코드 변경 유사성을 계산한다. 이후 Eclipse 프로젝트인 JDT와 CDT에 대한 사례 연구를 통해 제안된 방법의 효용성을 보였다.

• Journal of applied mathematics & informatics
• /
• 제7권2호
• /
• pp.653-664
• /
• 2000

The problem of inference about the unknown change-point with a change in mean is considered. We suggest a nonparametric change-point estimator using window and prove its consistency when the errors are from the distribution with the mean zero and the common variance. a comparison study is done by simulation on the mean, the variance, and the proportion of matching the true change-points.