• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제27권5호
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• pp.435-441
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• 2001

Orthognathic surgery for the correction of dentofacial deformities is a common elective procedure. That has proven over the years to be a safe operation with minimal long-term morbidity. But, there are many surgical complication including mal-union of the bone, TMJ problem, excessive bleeding, and permanent damage of inferior alveolar nerve. Among them excessive bleeding which focus is not clear is one of the serious complication because that is fatal and so a transfusion is performing for the prevention and management of that. Until the end of the 1980's, homologous blood transfusions were routinely necessary because of the large amounts of blood lost during surgery. Recently several blood-saving measures can be undertaken for orthognathic surgery patients before, during, and after the operation. We made a comparative study of an amount of blood loss, hematologic change and transfusion requirements based on a series of 40 consecutive patients undergoing single-jaw and double-jaw surgery. The purpose of this investigation was to make a comparative analysis of an amount of blood loss, post-operative hematologic change and duration of the procedure under induced hypotensive anesthesia in healthy orthognathic patients.

• Animal cells and systems
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• 제14권4호
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• pp.237-244
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• 2010

Stress urinary incontinence (SUI) is a common condition that primarily affects women. Here, we investigate the effects of human adipose-derived stem cells (ADSCs) in a rodent model of SUI. Female Sprague-Dawley rats at 7 weeks of age were randomly divided into three groups (n=8 per group): sham-operation, SUI-induction by transabdominal urethrolysis, and SUI-induction followed by transplantation of human ADSCs into the urethra. The abdominal leak point pressure at 8 weeks after the operation was markedly decreased by transabdominal urethrolysis, confirming successful induction of SUI. Interestingly, transplantation of human ADSCs into the urethra significantly blunted the decrease of abdominal leak point pressure in SUI-induced rats. Accordingly, we observed expression of ${\alpha}$-smooth muscle actin in a significant proportion of transplanted ADSCs, indicating differentiation of ADSCs into smooth muscle cells in the urethra. Moreover, the SUI-induced elevations of c-Fos immunoreactivities in the pontine micturition center (PMC) and in the ventrolateral periaqueductal gray (vlPAG) were clearly suppressed by transplantation of human ADSCs. These results imply that human ADSCs can be an effective therapeutic modality to ameliorate the symptoms of SUI.

• 대한전기학회논문지:전력기술부문A
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• 제54권5호
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• pp.217-225
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• 2005

In a power system, an out-of-step condition causes a variety of risk such as serious damage to system elements, tripping of loads and generators, mal-operation of relays, etc. Therefore, it is very important to detect the out-of-step condition and take a proper measure. Several out-of-step detection methods have been employed in relays until now. Most common method used for an out-of-step detection is based on the transition time through the blocking impedance area in R-X diagram. Also, the R-R dot out-of-step relay, the out-of-step prediction method and the adaptive out-of-step relay using the equal area criterion (EAC) and Global Positioning Satellite (GPS) technology have been developed. This paper presents the out-of-step detection algorithm using the time variation of the complex power. The complex power is calculated and the mechanical power of the generator is estimated by using the electrical power, and then the out-of-step detection algorithm which is based on the complex power and the estimated mechanical power, is presented. This algorithm may detect the instant when the generator angle passes the Unstable Equilibrium Point (UEP). The proposed out-of-step algorithm is verified and tested by using Alternative Transient Program/Electromagnetic Transient Program (ATP/EMTP) MODELS.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.313-315
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• 2005

In a power system, an out-of-step condition causes a variety of risk such as serious damage to system elements, tripping of loads and generators, mal-operation of relays, etc. Therefore, it is very important to detect the out-of-step condition and take a proper measure. Several out-of-step detection methods have been employed in relays until now Mo,;t common method used for an out-of-step detection is based on the transition time through the blocking impedance area in R-X diagram. Also, the R-R dot out-of- step relay, the out-of-step prediction method and the adaptive out-of-step relay using the equal area criterion (EAC) and Global Positioning Satellite (GPS) technology have been developed. This paper presents the out-of-step detection algorithm using the time variation of the complex power. The complex power is calculated and the mechanical power of the generator is estimated by using the electrical power, and then the out-of-step detection algorithm, which is based on the complex Power and the estimated mechanical power, is presented. This algorithm, may detect the instant when the generator angle passes the Unstable Equilibrium Point (UEP). The proposed out-of-step algorithm is verified and tested by using Alternative Transient Program/Electromagnetic Transient Program (ATP/EMTP) MODELS.

• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2008년도 학술대회 2부
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• pp.7-12
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• 2008

본 연구는 디지털기기 사용성향을 구성하는 요인들을 밝히고, 세대를 구분하는 것에 연구목적이 있다. 이를 위해 51개 문항으로 구성된 설문을 이용하여, 15세에서 49세에 이르는 우리나라 일반 사용자들로부터 639부의 데이터를 수거하여 요인분석, 군집분석 등의 분석을 실시하였다. 그 결과, 디지털기기 사용성향을 구성하는 11개의 요인을 추출하고, 각각 관심, 오락성, 단순성, 조작불안감, 실용성, 개성, 조작일관성, 기능의 다양성, 조작법 습득, 고장의 책임성, 대여도로 명명하였다. 이어서, 요인점수를 변수로 하는 군집분석을 실시, 전체 조사대상자를 적극적 수용자형, 소극적 추종자형, 보수적 무관심형으로 명명된 3개 군집으로 분류하였다. 그리고 연령을 변인으로 하는 교차분석을 반복적으로 실시한 후, 그 결과들을 종합함으로서, 연령이 군집출현에 강한 영향을 준다는 것을 확인하였고, 이를 바탕으로 1727세대, 2834세대, 3538세대, 3949세대의 4개가지로 세대구분하였다. 세대 외에 성별, 소득, 학력, 직업 등의 인구통계화적 변인들은 사용성향에 큰 영향을 주는 변인이 아님을 확인하였다. 이어, 이러한 세대구분 연구결과를 제품사용경험에 대한 코호트맵 선행연구결과와 비교함으로서, 3538 세대가 분기점 역할을 하는 원인에 대해 고찰하였다.

• 중소기업융합학회논문지
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• 제6권1호
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• pp.7-15
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• 2016

현대 사회에서 자동차, 철도, 항공우주, 원자력, 국방 등의 다양한 분야에서 대부분의 장치들이 소프트웨어를 내장하고, 제어용 소프트웨어 시스템이 탑재됨에 따라 소프트웨어의 안전성에 대한 중요도가 높아지고 있다. 다양한 산업 분야에서 소프트웨어가 사용되면서 소프트웨어에 의한 사고의 위협도 높아지기 때문에 소프트웨어 오동작에 의한 안전성 위협이 큰 이슈로 떠오르게 되었다. 소프트웨어의 사고는 사용자의 오조작에 의해서 발생할 수 도 있지만 가장 근본적으로는 설계 과정에서의 안전성에 대한 검증이 제대로 이루어지지 않아서 발생하게 된다. 따라서 본 논문에서는 소프트웨어 개발 프로세스에서 소프트웨어 안전성 분석 및 관리 활동이 어떻게 이루어져야 하는 가를 제시한다. 특별히 프로토타입이나 점진적 개발 프로세스에서의 안전성 분석 및 관리 활동의 적용 방안에 대하여 제시한다.

• 한국시뮬레이션학회논문지
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• 제22권1호
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• pp.1-8
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• 2013

신재생에너지원의 확대 보급 정책과 신재생에너지 공급 의무화 제도(RPS)의 도입으로 배전계통에 연계되는 분산전원이 증가되고 있다. 분산전원이 연계된 배전계통에서는 고장전류의 크기와 방향이 변화하게 되며, 이러한 고장전류의 변화는 기존 보호협조 체계에 대한 재검토를 요구한다. 전력연구원에서는 이러한 고장전류의 변화를 고려할 수 있는 보호협조 정정 알고리즘을 탑재한 시뮬레이션 프로그램을 개발하였다. 본 논문에서는 분산전원 연계 전, 후의 고장전류 변화를 분석하고, 시뮬레이션 프로그램을 이용하여 샘플 계통에 대한 보호협조 정정을 수행하였으며, 분산전원이 배전계통의 보호협조에 미치는 영향에 대하여 고찰하고 그 대책에 대하여 논하고자 한다.

• 한국가금학회지
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• 제10권1호
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• pp.1-22
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• 1983

The Purpose of this study is to examine both supply and demand side of broiler chicken in Korea. Especially the paper aims to investigate the broiler chicken production Dressing and marketing pattern which may affect the demand for it. It is generally understood that broiler chicken production becomes unstable because of frequent market price fluctuation mainly due to disequilibrium of quantities demanded ana supplied It is important to point out that marketing in the form dressed chicken has been enforced by the regulation in Seoul area since March 1st, 1983, though live birds have been customarily marketed for year. It is assumed that the subsituation of chicken meat for beef would save foreign exchanges, because increasingly large amount of beef is imported mainly thanked to a chronical shortage in local production. Main findings of this study may be summarized as follows: 1) Broiler chicker production has been rapidly increased recently, estimating 180-200 million head per year with the trend of contineous increase year after year. Price fluctuation during the year is found, especially summer and winter mainly due to seasonal demand change. It is known that mal-funconing of broiler chicken market may be one of the causes for a large Price fluctuation. Accordingly the increase of marketing efficiency may reduce the price fluctuation and also positively impact on creating demand for the chicken consumption. 2) It is also interesting to note that 90 percent of broilers are grown on the floor and almost 86 percent of total broilers composed of so called high-bros, weighing on an average more than 1.6kg per head Approximately 8 weeks are required for of around marketing birds at the feed efficiency of around 2.3-2.5 Average broiler farm raises between 1,000 and 2,000 head, showing a quite small scale of operation. Only a few sampled farmers follow an all-in and all-out method in broiler production.

• 정보관리연구
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• 제34권3호
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• pp.69-85
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• 2003

본 연구는 정부출연연구소인 한국과학기술연구원의 사례를 통해 전자 학술지가 전문도서관 운영 전반 즉, 예산, 정보 이용, 업무, 시설, 공간에 미치는 영향에 대해 조사 분석하였다. 이러한 분석을 통해 전문도서관 운영 측면에서 고려해야 할 요소들을 다음과 같이 제안하고 있다. 첫째, 전자 학술지 도입은 전문도서관 운영 전반에 영향을 미치기 때문에 직무별로 접근하지 말고 큰 틀에서 접근하여야 한다. 둘째, 현재 전자 학술지는 대부분 콘소시엄을 통해 구독하는 경우가 대부분이지만, 정보 제공 기관들과 정보 공유를 위한 협력망 구축 및 구독 방법을 다양화하여야 한다. 셋째, 전자 정보 운영 환경에 맞게 직무 분석을 통해 업무가 재설계되어야 한다. 넷째, 물리적 규모가 아닌 원하는 전자 정보를 이용할 수 있도록 서고 및 장비를 재구성 할 필요가 있다. 마지막으로, 전문도서관처럼 자료의 보존 보다는 시의 적절한 정보 활용을 중요시 하는 기관의 요구에 따른 사고의 전환이 필요하다.

• 운동영양학회지
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• 제13권2호
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• pp.147-153
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• 2009

Effect of whole body vibration exercise on intracerebral hemorrhage in rats. Intracerebral hemorrhage is one of the most devastating types of stroke. This disease is known to cause severe neurological damage and also has a very high mortality rate. In the present study, the effects of whole body vibration exercise on memory capability and apoptotic neuronal cell death in the hippocampal CA1 region following intracerebral hemorrhage in rats were investigated. Intracerebral hemorrhage was induced by injection of collagenase into the hippocampal CA1 region using a stereotaxic instrument. The rats were divided into 5 groups: the sham-operation group, the hemorrhage-induction group, the hemorrhage-induction and 8 Hz vibration exercise group, the hemorrhage-induction and 16 Hz vibration exercise group, and the hemorrhage-induction and 24 Hz vibration exercise group. The animals in the whole body vibration exercise groups received whole body vibration at 8 Hz, 16 Hz, and 24 Hz, respectively for 30 min once a day during 14 consecutive days. In the present results, the apoptotic neuronal cell death in the hippocampal CA1 region was significantly increased following induction of intracerebral hemorrhage, resulting in memory impairment. Whole body vibration exercise suppressed hemorrhage-induced apoptosis in the hippocampal CA1 region. This suppressive effect of whole body vibration exercise also alleviated hemorrhage-induced memory impairment. Here in this study, we have shown that whole body vibration exercise inhibited intracerebral hemorrhage-induced apoptotic neuronal cell death and thus facilitated recovery of brain function following intracerebral hemorrhage.