• 한국항공우주학회지
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• 제38권4호
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• pp.376-381
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• 2010

일반적으로 기체 구조물 개발시 운용조건에서의 구조설계 해석 검증 및 구조강도확인을 위해서 구조강도시험이 수행된다. 본 논문에서는 구조시험 하중부가방법 중 응력집중에 의해 파손되기 쉬운 재료를 기체 지지구조로 사용하고자 할 때 구조물 표면에 공기압을 이용하여 국부적 응력집중을 피하면서 분포하중을 부가할 수 있는 새로운 외력부가장치의 개발에 대하여 기술하였다. 본 장치는 부드러운 재질의 하중전달용 매개체를 이용하여 구조물 표면에 손상을 주지 않고 외력을 전달할 수 있으며, 임의형상 구조물에 대하여 쉽게 응용이 가능하다. 본 장치를 이용하여 평판구조물과 곡면구조물에 대하여 외력부가구조강도시험을 성공적으로 수행함으로써 적용시험기법의 타당성을 입증하였다.

• 한국건설관리학회논문집
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• 제13권2호
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• pp.80-90
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• 2012

2011년을 기준으로 국내 건설시장은 민간 부문과 공공부문의 발주 감소로 전반적인 건설 경기 침체가 되고 있는 실정이며 해외 건설의 경우는 플랜트에 편중된 시장 점유로 인해 전체 건설업에 대해서는 중국 및 인도 등에 경쟁력을 잃어가고 있다. 또한 선진국에 비해 고부가가치 기술경쟁력이 열위에 있는 상황에서 국내 건설사들의 경쟁력 강화에 대한 연구들이 이루어지고 있는데, 최근 국내 외에서 Pre-construction Service(이하 Pre-con Service)의 중요성이 부각되어 대형 건축 및 플랜트 프로젝트 발주 시 이를 통한 발주가 늘어나는 추세이다. 그러나 국내 건설사들의 Pre-con 업무에 대한 일반적인 이해부족과 업무 체계 정립이 미흡하여 Pre-con Service에 대한 대응 전략은 부족한 상황이다. 이에 본 연구에서는 국내 건설사의 해외 건설 시장 진출을 위한 Pre-con Service의 핵심 업무를 규명하고 그 중요도와 현 역량 수준을 비교 분석하여 이에 따른 역량 향상의 방향을 제시하고자 한다.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제21권3호
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• pp.196-202
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• 2018

Purpose: Treatment of chronic constipation and fecal impaction is usually outpatient and requires high or frequent doses of laxatives. However, there are children who fail outpatient treatments, sometimes repeatedly, and are ultimately hospitalized. We sought to compare the characteristics of the children who failed outpatient treatment and needed inpatient treatment vs those who achieved success with outpatient treatment, in an effort to identify attributes that might be associated with a higher likelihood towards hospitalization. Methods: In this retrospective cohort study, we reviewed the medical records of all patients aged 0 to 21 years, with chronic functional constipation and fecal impaction seen in the pediatric gastroenterology clinic over a period of 2 years. Results: Total of 188 patients met inclusion criteria. While 69.2% were successfully treated outpatient (referred to as the outpatient group), 30.9% failed outpatient treatment and were hospitalized (referred to as the inpatient group). The characteristics of the inpatient group including age at onset of $3.6{\pm}3.6years$ (p=0.02); black ethnicity (odds ratio [OR] 4.31, 95% confidence interval [95% CI] 2.04-9.09); p<0.001); prematurity (OR 2.39, 95% CI 1.09-5.26; p=0.02]; developmental delay (OR 2.20, 95% CI 1.12-4.33; p=0.02); overflow incontinence (OR 2.26, 95% CI 1.12-4.53, p=0.02); picky eating habits (OR 2.02, 95% CI 1.00-4.08; p=0.04); number of ROME III criteria met: median 4, interquartile range 3-5 (p=0.04) and $13{\pm}13.7$ constipation related prior encounters (p=0.001), were significantly different from the outpatient group. Conclusion: Identification of these characteristics may be helpful in anticipating challenges and potential barriers to effective outpatient treatment.

• 한국컴퓨터산업학회논문지
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• 제5권2호
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• pp.227-233
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• 2004

복합 스케줄링 문제는 컴퓨터의 기획(planning), 스케줄링(scheduling), 제약만족문제(Constraint Satisfaction Problem, CSP), 객체지향개념(object-oriented concept), 에이전트 시스템(agent system) 등의 여러 분야와 관련이 있다. 사용자의 선호도를 고려한 기법은 제약만족문제와 객체지향개념을 스케줄링에 적용하여 복합 스케줄링 문제를 해결하고자 하였다. 본 논문은 사용자의 선호도를 고려한 기법을 예약 문제에 적용하여 예약 시에 일어날 수 있는 문제점들을 해결하고자 하였다 특히 고객들의 만족도를 놀이기 위해서 고객들의 선호도를 고려하여 스케줄링을 한다. 객체에 근거한 예약 스케줄링 기법은 객체 지향 개념을 기반으로 하여 라 객체들이 사건들을 가지고 있으며, 이 사건들을 주어진 제약들에 만족하도록 목표인 보드에 배정하는 기법이다 각 객체들은 전체적인 만족 도를 고려하면서 그 객체들의 우선순위에 따라서 자원을 배정하고, 자원에 대한 객체의 선호도 차이를 가질 수 있게 하였다. 예약 스케줄링을 할 때 제약은 전역 제약과 지 역 제약으로 구성된다. 보드에 대한 정의와 모든 사건들에 대한 정보를 전역 제약으로 사용하고, 각 객체가 가지는 보드의 슬롯들에 대한 선호도를 지역 제약으로 사용한다. 사건의 배정을 실패하지 않고 백크래킹을 최소화하도록 알을 보는(look-ahead) 백크래킹 기법을 사용하여 전체 객체들의 만족 도를 높였다.

• 자원ㆍ환경경제연구
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• 제21권1호
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• pp.3-25
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• 2012

일반적으로 정부규제를 포함한 여러 제약적 환경에 직먼한 기업은 생산요소 투입단계에서 요소간의 비효율적인 배분으로 인하여 적정 수준 대비 각 요소의 과잉 혹은 과소 사용이 초래된다. 본 논문에서는 국내 화력발전산업을 대상으로 적정 수준의 자본스톡 규모를 전제로 화석연료간의 효율적 배분 여부를 검증하고 각 연료별 과잉 과소 투입량을 산정한 다음 각 연료를 적정 수준으로 투입할 경우 확보할 수 있는 잠재적 $CO_2$ 감축량을 추정하였다. 1987~2008년 기간에 걸쳐 모든 화석연료에 대한 효율적 배분 조건이 기각됨에 따라 화력발전소는 주어진 연료의 시장가격으로 생산비용의 최소화를 달성하지 못하는 것으로 나타났다. 또한 두 연료간의 효율적 배분 여부를 검증한 결과 석탄과 석유 간, 석탄과 가스 간, 그리고 석유와 가스 간의 조건 모두 기각되었다. 평균적으로 석탄과 가스는 과잉 사용되었으며, 석유는 과소 투입된 것으로 나타났다. 연료간의 배분 효율화를 통하여 연간 평균적으로 1.000만 톤 이상의 $CO_2$ 감축이 가능한 것으로 추정되었다.

• Journal of Chest Surgery
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• 제50권1호
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• pp.36-40
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• 2017

Background: Surgical treatment of thoracic outlet syndrome (TOS) is necessary when non-surgical treatments fail. Complications of surgical procedures vary from short-term post-surgical pain to permanent disability. The outcome of TOS surgery is affected by the visibility during the operation. In this study, we have compared the complications arising during the supraclavicular and the transaxillary approaches to determine the appropriate approach for TOS surgery. Methods: In this study, 448 patients with symptoms of TOS were assessed. The male-to-female ratio was approximately 1:4, and the mean age was 34.5 years. Overall, 102 operations were performed, including unilateral, bilateral, and reoperations, and the patients were retrospectively evaluated. Of the 102 patients, 63 underwent the supraclavicular approach, 32 underwent the transaxillary approach, and 7 underwent the transaxillary approach followed by the supraclavicular approach. Complications were evaluated over 24 months. Results: The prevalence of pneumothorax, hemothorax, and vessel injuries in the transaxillary and the supraclavicular approaches was equal. We found more permanent and transient brachial plexus injuries in the case of the transaxillary approach than in the case of the supraclavicular approach, but the difference was not statistically significant. Persistent pain and symptoms were significantly more common in patients who underwent the transaxillary approach (p<0.05). Conclusion: The supraclavicular approach seems to be the more effective technique of the two because it offers the surgeon better access to the brachial plexus and a direct view. This approach for a TOS operation offers a better surgical outcome and lower reoperation rates than the transaxillary method. Our results showed the supraclavicular approach to be the preferred method for TOS operations.

• 한국화재소방학회논문지
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• 제30권4호
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• pp.20-26
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• 2016

원자력발전소의 화재방호 목적은 예방, 화재의 진압 및 영향을 완화하는 데 있으며, 화재가 발생하면 원자로를 안전하게 정지하여 유지하고 환경으로 방사성물질의 유출을 최소화하는 것이다. 미국의 원자력규제위원회는 10CFR50.48과 10CFR50 APP.R을 발행한 이래 지난 20여년간 화재방호와 관련하여 많은 일반 통신문(Generic Communications)을 발행하였으며, 미국원전 발전사업자(Nuclear Energy Institute)에서는 회로고장 해결을 위한 다중오동작과 관련된 결정론적 방법 등을 사용과 연계하여 위험도정보를 활용한 화재 안전정지분석 방법론을 개발하였다. 본 논문에서는 중수로원전의 주제어실 화재시 화재안전정지분석 방법론을 적용하여 안전정지용 한 계열의 안전관련 계통 및 기기가 손상되어도 원자로의 사고 후 안전정지를 달성하고 유지함을 확인하였다.

• 의학교육논단
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• 제12권1호
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• pp.9-22
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• 2010

It is the most important thing at present for physicians to posses the qualification of medical professionalism. A lot of medical schools have made all-out efforts to develop leaders of medicine, who will be able to meet the needs of medical professionalism in this complex medical environment. The purpose of this study is to review the cognitive base of medical professionalism leading the curriculum development of medical professionalism. The discussion of medical professionalism started in the 20th century. During the 1960s, there were attempts to reshape the concepts and attributes of medical professionalism. The government began to intervene in the autonomy of physician and the self regulation policy of medical society in 1970s. Physician may be asked to play as a healer and professional (what?) during their medical practice. The fundamental role of healer such as care, compassion, honesty, integrity, confidentiality, ethical behaviors, and respect with patients were nothing fresh to tell even though the age was changed. The attributes of professional which are physician's autonomy, self regulation, teamwork, and responsibility to society has been changed dramatically over the past five decades. In general, medical educators agreed that professionalism is demonstrated through a foundation of clinical competence, communication skills, and ethical and legal understanding, upon which is built application of the principles of professionalism: excellence, accountability, altruism, and humanism. If physicians fail to show professionalism in society, they will confront the crisis which can be under the government control. The only way to keep their autonomy is to practice medical professionalism. So far today, medical schools have laid more stress on competence than value standards in educational systems and it was restricted for medical students to learn the value standards for medical practice. To understand and practice the medical professionalism, it is the most realistic way to solve the complicated medical problems.

• 한국가구학회지
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• 제22권3호
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• pp.160-173
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• 2011

Increased internet use under a ubiquitous environment may be called as a great human information space revolution followed by Industrial Revolution. This revolution is exerting its significant influence over all the industry as a whole with speed faster than that of any other times. Along with this trend, if furniture design field that leads living culture should fail to jump on this main stream without noticing it, it may be reduced to a unpopular field some day without any sign of recovery. Under this background, this study is intended to recognize a goal aiming at understanding our rapidly changing living environment and leading our way positively. Currently, our surrounding living environment is immersed in computers here and there and Mark Weiser once defined a system that moves in advance before an action as ubiquitous computing and in this respect, I am going to observe a detailed transformation process of space. First nature of the space may be defined as atoms, a physical space equivalent to a spatial element and Bits space that is untouchable is usually called as 2nd space and a combination of atoms and Bits is an intelligent space - 3rd space - that can be intelligible without touching it and finally, this space is called as a ubiquitous space. This spatial transformation is developed by several changes of living environment and we may call it as living trend or interior design trend. Transformation in terms of social perspective, space structural perspective and digital technique perspective may be enumerated. These transformations were surveyed based on its contents being implemented at a future housing exhibition hosted by 5 construction companies along with fusion of information furniture and furniture depending on each housing space. In conclusion, it could be realized that most of the companies were decorating future space by implementing ubiquitous environment as a success factor of future housing market. It may be meaningful to note once again that under an interior environment, a fusion of furniture and information furniture is required considering interior trend elements.

• 한국자동차공학회논문집
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• 제23권4호
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• pp.444-453
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• 2015

In the previous study, several problems were observed in a NG conversion vehicle, which were fail of air-fuel ratio closed loop control, aggravated fuel economy, increased harmful emission and declined roadability. It was provisionally supposed that the mismatch of injection system with the engine caused these performance deterioration. In this context, the characteristics of fuel injection system of commercial conversion kit for NG were investigated experimentally varying the engine speed, fuel rail pressure and volume. The results are as follows; The injection quantity decreases as the engine speed increases due to the extremely small rail volume of the presenting system and flow rate of No. 2 injector are always lower than that of the other ones regardless of the speed under the dynamic operation condition. Furthermore the existing system does not meet the required fuel quantity for the normal engine operation over 3000 RPM. On the other hands, the large rail volume systems ease and/or eliminate the difference of injection quantity between the injectors according to the speed variation, however, these systems decrease injection flow rate and still cannot supply sufficient fuel. Finally, suitable combination of the higher rail pressure and the larger rail volume might be a solution about these problems.