• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2000년도 추계학술대회 논문집
• /
• pp.3-6
• /
• 2000

The magnetic bearing system are intrinsically unstable, and need the feedback control of electromagnetic forces with measured displacements. So the controller design plays an important role in constructing high performance magnetic bearing system. In case of magnetic bearing system, the order of identified model is high because of unknown dynamics included in closed loop systems - such as sensor dynamics, actuator dynamics - and non-linearity of magnetic bearings itself. In this paper the identification and robust control of flexible rotor supported by magnetic bearing are discussed. We measure and identify overall system that contains not only flexible rotor model but also magnetic bearing and time delay. The structured and unstructured uncertainties are modeled that cover variations of natural frequencies, uncertainties in sensor and actuator gains and unmodeled dynamics. And desired performances are specified with several weighting function. Using augmented system that includes identified model, uncertainties, and weighting functions, μ-synthesis is applied to flexible rotor supported with magnetic bearing. The flexible rotor was spin up over the first flexible critical speed.

• 보건의료산업학회지
• /
• 제5권1호
• /
• pp.133-145
• /
• 2011

The purpose of this study is to analyze the influence of external environment, organizational characteristics on informatization level in hospital settings, and to provide suggestions to improve the informatizaiton level of strategic information system of hospitals. In order to achieve study purpose, causal model was developed and empirically tested. Data were collected from 716 managers of 89 hospitals keeping information system in Busan and KyungNam Province using self-administered structured questionnaire. Major results of this study were as follows; First, among hospitals which had information training programs, informatization capacity was significantly higher. Moreover, informatization capacity was significantly varied by ownership type, institutional level, and number of beds of hospitals. Second, environmental uncertainty, intra-industry competition intensity, decision-making concentration, work standardization variables and perceived benefits were found to be significant affecting factors on informatization capacity as a result of path analysis. Third, support of top-management and perceived benefits were found to be significant affecting factors on informatization capability as a result of path analysis. Especially, informatization capability was positively affected by informatization capacity. Finally, perceived benefits was found to be significant affecting factors on informatization competency as a result of path analysis. Especially, informatization competency was positively affected by informatization capability.

• 대한안전경영과학회지
• /
• 제10권1호
• /
• pp.11-22
• /
• 2008

Humans are well-known for being adept at using intuition and expertise in many situations. However, human experts are still susceptible to errors in judgment or execution, and failure to recognize the limits of knowledge. This would happen especially in semi-structured situations, in multi-disciplinary settings, under time or other stress, under uncertainty, or when knowledge is outdated Human errors are caused by cognitive biases, attentional slips/memory lapses, cultural motivations, and missing knowledge. The purpose of this research is to study errors of human experts committed in judgment and the general idea of critiquing systems as corresponding plan. Compared to expert systems, critiquing systems are narrowly focused programs useful in limited situations for collaborating with and supporting experts in their task activities. It supports an expert by detecting the human's errors by deploying various strategies that stimulate humans to improve their performance. A variety of types of critiquing systems has spread through numerous application areas.

• Child Health Nursing Research
• /
• 제13권4호
• /
• pp.454-466
• /
• 2007

Purpose: To explore the experiences of parenting from the mothers of children with severe CHD and to develop a grounded theory about their experiences. Method: Grounded theory method guided the data collection and analysis. A purposeful sample of 16 mothers of children with severe CHD participated during the period 2003. The data were collected by semi-structured individual interviews. Results: "Raise with dignity" emerged as the core phenomenon. 'Powerlessness' came up as the central concept. The causal conditions working on powerlessness was 'living with a bomb in the heart': uncertainty and the context were 'confronting people's eyes', 'developing child's adaptability'. An intervening condition was 'forming a support system' and consequences for coping with powerlessness were 'overcome' or 'ambivalence' using the strategies for mother's positive personality, care role perception, accepting, acknowledgement, and managing the body and mind. Conclusions: In the results of this study, the mothers of children with severe CHD are continue to struggle with life during children's growth and repeated attacks of disease. They need to be provided with skills to cope with physical and mental problems in rearing the children with expertized information for the entire period of growth.

• 한국중재학회지:중재연구
• /
• 제26권3호
• /
• pp.3-26
• /
• 2016

The preferential Rules of Origin (RoO) govern tariff preferences that are given in accordance with the FTA. However, relatively few studies have been devoted to the procedures in settling disputes that are relevant to RoO under the FTA. This study is a first attempt at analyzing the applicability and the potential improvement in dispute settlement procedures in FTAs targeted at the preferential RoO. By exploring three dispute cases involving the preferential RoO, it is suggested that restrictiveness, complexity, and uncertainty that are inherent in the preferential RoO may trigger political tension and dispute. Forming a panel that is capable of mitigating political tension, facilitating participation and early cooperation of experts and stakeholders, and establishing a well-structured enforcement procedure are essential in dispute settlement procedures to resolve disputes involving cases on RoO. Furthermore, the current dispute settlement procedure that hinders the private sector's access should be changed to one that is more open to private sector entities, such as companies, to facilitate the enforcement of the decision. Given that more improved FTA dispute settlement procedure may guarantee the enforcement and application of the FTA preferential treatment in relation with more politically powerful states and foster genuine free trades, more in-depth studies must be conducted on this topic.

• 한국초등과학교육학회지:초등과학교육
• /
• 제24권4호
• /
• pp.426-434
• /
• 2005

In this study, elementary school students' responses toward a discrepant event about a float-or-sink problem were investigated through semi-structured interviews. Initial participants were 61 fifth-grade students from two elementary schools. After excluding the students who did not possess the target misconception from the results of a preconception test and who were not willing to participate in an interview, 31 students (14 males and 17 females) were finally interviewed by two teacher-interviewers. During the interviews, students were first provided with a hands-on experiment which was the same as the situation in the preconception test, and then they were asked about believability of the discrepant event, inconsistency between the discrepant event and their existing conceptions, and belief change after experiencing the discrepant event. Interviews were audio- and video-taped, and then were transcribed by two interviewers. After analyzing the interview transcriptions, we found four types of students' responses; rejection, uncertainty, peripheral belief change, and belief change. We also found that belief change response type should be classified into three distinctive subtypes; belief decrease, ad-hoc belief change, and analytical-abductive belief change.

• The Journal of Asian Finance, Economics and Business
• /
• 제8권5호
• /
• pp.851-861
• /
• 2021

This study aims to explore the specific risks in family small-medium enterprises (SMEs) and explain how they manage these risks to sustain and expand. In Indonesia, family business composes around 95 percent of all businesses and contributes about 80 percent to the country's economy. SMEs contribute approximately 57.8 percent to the nation's gross domestic product. Risk management poses challenges to the family business's survival, as family members do not take actions on risk. The assessment of risk is difficult and family businesses lack the ability to determine risk management priorities, including risk management review processes to evaluate risk, thus leading to family business failures. Applying the case study approach, in-depth semi-structured interviews were conducted in seven family SMEs comprising fifteen informants. Additionally, a focus group discussion consisting of three experts is conducted to reaffirm the findings from the interviews, observations, and field notes. The research identified the specific risks and how the family owners strategize to safeguard against these risks such as cash flow deficiency, operations dysfunction, cultural frailty, disharmony, transgenerational entrepreneurship failure, political uncertainty, and unprofessionalism. Comprehending these risks and their strategic decisions elucidated in this research could enable the family owners and key non-family professionals to work hand-in-hand to thrive over the family business risks together. Further avenues of research regarding family business risk management are also suggested in this study.

• 한국수자원학회논문집
• /
• 제54권5호
• /
• pp.321-334
• /
• 2021

일반적으로 레이더 강수량 추정에 활용되는 Marshall-Palmer 관계식은 강수현상의 계절적 변동성을 고려하지 않고 선별된 강수사상에 대하여 시공간적으로 고정된 매개변수를 적용하여 레이더 강수량을 추정하므로 실제 강수량과 추정된 레이더 강수량은 정량적인 오차가 발생할 수 있다. 이러한 제약성을 극복하고자 본 연구는 장기간 레이더 반사도 인자를 가용하여 레이더 반사도-강수량 관계식 매개변수를 Bayesian 추론기법으로 보정하고 불확실성을 정량화하여 레이더 강수량의 편의 보정을 수행하였다. Bayesian 추론기법 기반으로 추정된 레이더 반사도-강수량 관계식의 보정 매개변수는 계절성이 규명되었으며 지역적 특성이 존재하였다. Bayesian 추론기법을 통하여 산정된 레이더 강수량은 Marshall-Palmer 관계식의 과소추정 문제를 극복하고 지상 강수특성을 정량적으로 현실성 있게 재현하였다. 본 연구결과는 집중호우 발생 시 능동적인 유역단위 수자원 해석 시스템을 구축하여 국가적 레이더 자원의 가치를 향상할 수 있을 것으로 판단된다.

• 재활간호학회지
• /
• 제2권2호
• /
• pp.243-256
• /
• 1999

The purpose of this study was to identify the degree of self-care activities of stroke patients, the family burden, and the educational needs of primary caregivers. A descriptive survey research was conducted in 97 stroke patients and their respective primary caregivers. Data were collected by the interviews using a structured questionnare from July 26th to August 5th, 1999. NIH stroke status was $12.15{\pm}8.40$, the degree of self-care activities of stroke patients was $26.85{\pm}9.39$. The score of objective burden of primary caregivers was $31.24{\pm}4.81$ and subjective burden was $24.30{\pm}6.99$. The score of the educational needs was $89.78{\pm}9.99$. We present several imformations about clients from these scores as follows: The patients were convalescent and their depentant level of self- care was middle range; The objective burden was higher than the subjective burden; And the educational needs of family caregivers were very high. The Elain Mattis Educational Wants of Family Caregivers of Disabled Adults Questionnaire was used to assess the educational needs of primary caregivers of stroke patients. The results of this research are offered to help nurses understand the feelings of uncertainty about the new and unexpected role that family caregivers face and to help nurses meet the needs of families preparing to care stroke survivors at home.

• 한국건설관리학회:학술대회논문집
• /
• 한국건설관리학회 2003년도 학술대회지
• /
• pp.485-490
• /
• 2003

최근 대내외적인 건설환경의 급격한 변화와 건설공사의 대형화${\cdot}$복잡화 추세는 내외부적으로 많은 리스크 요인을 증대시키고 있기 때문에, 이에 대한 합리적이고 효율적인 관리방안의 중요성이 크게 대두되고 있다. 본 연구에서는 이러한 리스크 관리방안의 하나로서, 사업추진과정에서의 공사비 증액이 매우 제한되어 있어 입찰단계에서 견적금액의 불확실성 요소(예비비)를 고려해야만 하는 턴키공사 등 대형 건설공사를 대상으로, 이에 내재된 리스크요인의 정량화를 통해 합리적이고 적절한 예비비를 산정할 수 있는 모델을 제시하고자 한다. 예비비 산정모델의 개발을 위하여 실제 수행된 프로젝트를 선정하여 각 공사의 예비비 집행현황, 공사비 현황 등의 자료를 토대로 공사비에 영향을 미치는 인자를 도출하였으며, 몬테칼로 시뮬레이션(Monte Carlo Simulation)과 영향도(Influence Diagram), 의사결정 수형도(Decision Tree)를 혼합한 CRM(Cost Risk Model)을 적용하여 이러한 리스크 인자의 영향을 구조화하였다. 또한 구축된 모델을 기 완료된 대형공사에 적용하여 그 타당성을 검증하고자 하였다.