• 천문학논총
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• 제27권4호
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• pp.153-159
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• 2012

We constructed an unbiased asteroid catalog from the mid-infrared part of the All-Sky Survey with the Infrared Camera (IRC) on board AKARI. About 20% of the point source events recorded in the IRC All-Sky Survey observations were not used for the IRC Point Source Catalog in its production process because of a lack of multiple detection by position. Asteroids, which are moving objects on the celestial sphere, are included in these "residual events" We identified asteroids out of the residual events by matching them with the positions of known asteroids. For the identified asteroids, we calculated the size and albedo based on the Standard Thermal Model. Finally we had a new brand of asteroid catalog, which contains 5,120 objects, about twice as many as the IRAS asteroid catalog.

• 인터넷정보학회논문지
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• 제4권6호
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• pp.13-24
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• 2003

그리드 기술은 지리적으로 분산된 컴퓨팅 자원을 활용하기에 다양한 자원에 대한 정보를 관리하는 기술이 필요하며, 이는 자원 관리 시스템에서 자원을 모니터링하여 이루어진다. 자원 상태 정보가 실시간으로 변하여 주기적으로 모니터링을 해야 하므로 이에 따른 오버헤드가 예상된다. 본 논문에서는 CPU상태 변화 정도를 관찰하여 시스템 상태를 파악하고 이를 모니터링 주기에 적용시키고자 한다. 즉 그리드 환경의 중요한 요소인 자원의 상태를 고려하여 자율적으로 자원의 상태에 따른 모니터링 주기를 조절하는 시스템을 모델링 하였다. 자원의 CPU 상태를 관찰해 CPU의 상태 변화율에 따라 자원의 상태 변화를 파악하여 모니터링 주기를 조절함으로써 모니터링에 의한 오버헤드가 감소하였음을 실험을 통해 증명하였다.

• Industrial Engineering and Management Systems
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• 제8권1호
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• pp.37-46
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• 2009

Patient safety has become a growing concern in health care. The U.S. Institute of Medicine (IOM) report "To Err Is Human: Building a Safer Health System" in 1999 included estimations that medical error is the eighth leading cause of death in the United States and results in up to 100,000 deaths annually. However, many adverse events and errors occur in surgical practice. Within all kinds of surgical adverse events, wrong-side/wrong-site, wrong-procedure, and wrong-patient adverse events are the most devastating, unacceptable, and often result in litigation. Much literature claims that systems must be put in place to render it essentially impossible or at least extremely difficult for human error to cause harm to patients. Hence, this research aims to develop a prototype system based on active RFID that detects and prevents errors in the OR. To fully comprehend the operating room (OR) process, multiple rounds of on site discussions were conducted. IDEF0 models were subsequently constructed for identifying the opportunity of improvement and performing before-after analysis. Based on the analysis, the architecture of the proposed RFID-based OR system was developed. An on-site survey conducted subsequently for better understanding the hardware requirement will then be illustrated. Finally, an RFID-enhanced system based on both the proposed architecture and test results was developed for gaining better control and improving the safety level of the surgical operations.

• 간호행정학회지
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• 제19권3호
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• pp.340-350
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• 2013

Purpose: This study was done to identify relationships among post-traumatic stress (PTS), job stress and turnover intention in emergency department (ED) nurses. Methods: Participants were 250 ED nurses who had worked for one month or longer in the ED one of three university hospitals or seven general hospitals in Daegu City or Gyeong Buk Province in Korea. Structured questionnaires were used to measure PTS, job stress, and turnover intention of participants. Data were analyzed using descriptive statistics, one-way ANOVA, path analysis, and stepwise multiple regression with the SPSS program. Results: There were significant relationships between PTS, job stress and turnover intention. PTS influenced turnover intention directly and was indirectly mediated by job stress. The experience of traumatic events influenced PTS, job stress, and turnover intention. Indirect experience of traumatic events in the ED was an important predictor, explaining 20.1% of PTS in high-risk post-traumatic participants. Conclusion: PTS can be an important factor for job stress and turnover intention. The direct and indirect experience of traumatic events can influence PTS, job stress, and turnover intention in ED nurses. Based on these results, strategies for managing PTS and relating job stress are recommended to reduce turnover intention in ED nurses.

• 대한가정학회지
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• 제34권3호
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• pp.305-325
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• 1996

This study was designed to compare mothers' beliefs of literacy development and home literacy environment and to explore how the children interacted with their mother during literacy activities and how they used the strategies to develop knowledge of literacy. The qualitative data was collected from multiple sources of naturalistic information and analyzed through triangulation of diverse methods including participant observations in the home, parental during literacy events, written logs kept by the mothers, the children's writing products, three emergent assessment forms, and photographs. The three preschoolers and their mothers provided different literacy experiences to support their children's emerging conventional literacy development. Child 1's mother highly valued the rich home literacy environment and the child 1's initiative interactions during literacy events. Child 3's home literacy context was very similar to her Montessori classroom's phonic approach and writing skills. Child 2 was provided with an inappropriate literacy environment at home through direct instruction and an emphasis on correct writing. All of the children were interested and attended to story. Child 1 interacted with her mother in expanded cycles as child's initiation, mother's clarification, and child's evaluation, compared with the child 2's simple cycle and the child 3's classroom-like cycle as mother's initiation, child's response, and mother's evaluation. The children and their mothers employed a number of diverse strategies to understand knowledge of literacy. Importantly parent education needs to emphasize the importance of playful one to one mother-child interaction, a functional holistic literacy environment., and strategies for expanding child's knowledge with parent as mediator.

• 여성건강간호학회지
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• 제20권1호
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• pp.38-47
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• 2014

Purpose: This study aimed to identify related factors of prenatal depression by stress-vulnerability and stress-coping models for pregnant women. Methods: A cross-sectional survey design with a convenience sampling was used. A total of 107 pregnant women who visited a general hospital in a metropolitan city were recruited from August to October, 2013. A structured questionnaire included the Korean version of Beck Depression Inventory II, and the instruments measuring Self-Esteem, Marital Satisfaction, Pregnancy Stress, Stressful Life Events, and Coping. The data were analyzed using descriptive statistics, t-test, Parson's correlation analysis, and stepwise multiple regression. Results: The mean score of prenatal depression was $11.95{\pm}6.2$, then showing 19.6% with mild depression, 15.0% with moderate depression, and 0.9% with severe depression on BDI II scale. Prenatal depression had positive correlation with pregnancy stress (r=.55, p<.01), stressful life events (r=.26, p<.01) and negative correlation with self- esteem (r=-.38, p<.01), marital satisfaction (r=-.40, p<.01), and coping (r=-.21, p<.05). Factors of pregnancy stress, self-esteem, stressful life events, and planned pregnancy explained 38% of the total variance of prenatal depression. Conclusion: These findings show that health providers need to assess prenatal depression and to control the influencing factors.

• 대한조선학회논문집
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• 제59권3호
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• pp.164-172
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• 2022

A HAZID is a brainstorming workshop to identify hazards in an early phase of a project. It should be flexible to capture all probable accidents allowing experienced participants to exploit their expertise and experiences. A bowtie analysis is a graphical representation of major accident hazards elaborating safety measures i.e. barriers. The result of these workshops should be documented in an organized manner to share as good as possible details of the discussion through the lifetime of the project. Currently results are documented using a three-step representation of an accident; causes, top event and consequences, which cannot capture correctly sequence of events leading to various accidents and roles of barrier between two events. Another problem is that barriers would be shown repeatedly leading to a misunderstanding that there are an enough number of safety measures. A new bowtie analysis method is proposed to describe an accident in multiple steps showing relations among causes or consequences. With causes and consequences shown in a format of a tree, the frequencies of having the top event (Fault tree analysis) and various consequences (Event tree analysis) are evaluated automatically based on the frequency of initiating causes and the probabilities of failure of barriers. It will provide a good description of the accident scenario and help the risk to be assessed transparently.

• Wind and Structures
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• 제38권3호
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• pp.171-191
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• 2024

Wind Driven Rain (WDR) poses a significant threat to the building environment, especially in hurricane prone regions by causing interior and content damage during tropical storms and hurricanes. The damage due to rain intrusion depends on the total amount of water that enters the building; however, owing to the use of inadequate empirical methods, the amount of water intrusion is difficult to estimate accurately. Hence, the need to achieve full-scale testing capable of realistically simulating rain intrusion is widely recognized. This paper presents results of a full-scale experimental simulation at the NHERI Wall of Wind Experimental Facility (WOW EF) aimed at obtaining realistic rain characteristics as experienced by structures during tropical storms and hurricanes. A full-scale simulation of rain in strong winds would allow testing WDR intrusion through typical building components. A study of rain intrusion through a sliding glass door is presented, which accounted for the effects of multiple wind directions, test durations and wind speeds; configurations with and without shuttering systems were also considered. The study showed that significant levels of water intrusion can occur during conditions well below current design levels. The knowledge gained through this work may enhance risk modeling pertaining to loss estimates due to WDR intrusion in buildings, and it may help quantify the potential reduction of losses due to the additional protection from shuttering systems on sliding glass doors during winds.

• 한국지능시스템학회논문지
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• 제16권3호
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• pp.291-296
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• 2006

상황은 단일 사건에 의해 결정되는 경우도 있지만, 많은 경우 일련의 사건이 특정 시간 제약을 만족하면서 발생할 때 상황이 결정된다. 따라서 상황에 대한 추론은 시간 제약 조건 만족 여부와 함께 사건의 발생을 순서를 확인하는 방법으로 수행될 수 있다. 한편, 어떤 상황은 분명하게 정의되는 것이 아니라 애매한 개념을 사용하여 기술되기 때문에, 퍼지 개념을 이용한 상황 기술과 이에 대한 추론이 필요하다. 한편, 유비쿼터스 환경에서와 같이 여러 대상에 대한 상황을 유추하여 서비스를 제공해야 하는 경우에, 대상 간에 동일한 상황이 발생할 수 있기 때문에 이에 대한 고려가 필요하다. 이러한 상황 추론을 위해서 이 논문에서는 Fuzzy Colored Timed Petri net 모델이라는 상황 추론 모델에 대해서 제안한다. 제안한 모델은 Timed Petri net 성질을 이용하여 일련의 사건 발생을 모델링하고, Colored Petri net의 성질을 이용하여 다수 대상에 대한 상황 추론을 허용하며, fuzzy 토큰 개념을 이용하여 애매한 개념을 사용하여 정의된 상환에 대한 추론을 가능하게 한다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.544-544
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• 2014

Energy harvesting technology, which scavenges electric power from ambient, otherwise wasted, energy sources, has been explored to develop self-powered wireless sensors and possibly eliminate the battery replacement cost for wireless sensors. Among ambient energy sources, vibration energy can be converted into electric power through a piezoelectric energy harvester. For the last decade, although tremendous advances have been made in design methodology to maximize harvestable electric power under a given vibration condition, the research in reliability assessment to ensure durability has been stagnant due to the complicated nature of the multiple failure modes of a piezoelectric energy harvester, such as the interfacial delamination, fatigue failure, and dynamic fracture. Therefore, this study presents the first-ever system reliability analysis for multiple failure modes of a piezoelectric energy harvester using the Generalized Complementary Intersection Method (GCIM), while accounts for the energy conversion performance. The GCIM enables to decompose the probabilities of high-order joint failure events into probabilities of complementary intersection events. The electromechanically-coupled analytical model is implemented based on the Kirchhoff plate theory to analyze its output performances of a piezoelectric energy harvester. Since a durable as well as efficient design of a piezoelectric energy harvester is significantly important in sustainably utilizing self-powered electronics, we believe that technical development on system reliability analysis will have an immediate and major impact on piezoelectric energy harvesting technology.