• 한국수자원학회논문집
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• 제48권12호
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• pp.969-979
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• 2015

본 연구에서는 가뭄의 특성분석에 유리하며, 확률론적 접근이 가능한 은닉 마코프 모델(HMM) 기반의 가뭄 분석 기법을 적용하였다. HMM 기반의 가뭄의 심도뿐만 아니라 지속시간을 동시에 평가할 수 있도록 코플라 함수 기반의 이변량 가뭄빈도해석 기법을 도입하여 우리나라의 2015년 가뭄 빈도를 평가하였다. 가뭄빈도분석 결과 최근 40년 자료를 기준으로 영동지방에 비해 영서지방이 전체적으로 가뭄이 발생할 경우 가뭄의 심도가 큰 것으로 평가되었다. 심한가뭄의 발생 비율의 경우에 철원의 경우 10%를 상회하는 등 임진강 유역에서 상대적으로 심한가뭄의 발생비율이 크다는 것을 확인할 수 있었다. 한강유역 일부지점에서는 2014/2015년의 가뭄 지속기간 및 심도의 결합재현기간이 1,000년이 넘는 가뭄이 발생하고 있는 것으로 평가되었다. 특히 북한강 및 임진강 유역에 심한 가뭄이 발생하고 있으며 전반적으로 100년 이상의 기왕최대가뭄을 나타내고 있는 것으로 판단되었다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제41권2호
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• pp.102-108
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• 2015

In surgery for facial asymmetry, mandibles can be classified into two types, rotational and translational, according to the required mandibular movements for surgery. During surgery for rotational mandibular asymmetry, a bilateral sagittal split ramus osteotomy (BSSRO) may cause a large bone gap between the proximal and distal segments as well as condylar displacement, resulting in a relapse of the temporomandibular joint disorder, especially in severe cases. The intraoral vertical ramus osteotomy has an advantage, in this respect, because it causes less rotational displacement of the proximal segment on the deviated side and even displaced or rotated condylar segments may return to their original physiologic position. Unilateral intraoral vertical ramus osteotomy (UIVRO) on the short side combined with contralateral SSRO was devised as an alternative technique to resolve the spatial problems caused by conventional SSRO in cases of severe rotational asymmetry. A series of three cases were treated with the previously suggested protocol and the follow-up period was analyzed. In serial cases, UIVRO combined with contralateral SSRO may avoid mediolateral flaring of the bone segments and condylar dislocation, and result in improved condition of the temporomandibular joint. UIVRO combined with contralateral SSRO is expected to be a useful technique for the treatment of rotational mandibular asymmetry.

• 아태비즈니스연구
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• 제14권4호
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• pp.431-444
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• 2023

Purpose - This study applies the traditional Structure-Conduct-Performance (SCP) model from industrial organization theory to investigate the relationship between market structure and performance in China's banking industry. Design/methodology/approach - For analysis, financial data from the People's Bank of China's "China Financial Stability Report" and financial reports of 6 state-owned banks and 11 joint-stock banks for the period 2010 to 2021 were collected to create a balanced panel dataset. The study employs panel fixed-effects regression analysis to assess the impact of changes in market structure and ownership structure on performance variables including return on asset, profitability, costs, and non-performing loan ratios. Findings - Empirical findings highlight significant differences in the effects of market structure between state-owned and joint-stock banks. Notably, increased market competition positively correlates with higher profits for state-owned banks and with lower costs for joint-stock banks. Research implications or Originality - State-owned banks demonstrate larger scale and stability, yet they struggle to respond effectively to market shifts. Conversely, joint-stock banks face challenges in raising profitability against competitive pressures. Additionally, the study emphasizes the importance for Chinese banks to strengthen risk management due to the increase of non-performing loans with competition. The results provide insights into reform policies for Chinese banks regarding the involvement of private sector in the context of market liberalization process in China.

• Archives of Reconstructive Microsurgery
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• 제7권2호
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• pp.95-101
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• 1998

From march 1993 to march 1998, twenty consecutive transmetacarpal replantations and revascularizations were reviewed retrospectively. Nine patients sustained severe and diffuse crush injuries, four patients had local crush injuries, and seven suffered guillotine type amputation. Six replantations and fourteen revascularizations were performed. 76 of 81 replantable digits(93%) were salvaged. 15 patients required secondary surgery, 10 patients for tendon and joint scarring and 5 for nonunions or malunions. Intrinsic muscle function and pinch and grip strengths were weak or absent. According to Chen's grading system of functional return, 2(10%) were grade I, 6(30%) were grade II, 10(50%) were grade III, and 2(10%) grade IV. The follow-up period ranged from 6months to 46 months. Only 3 patients resumed his prior occupation(one as a supervisor); 2 were permanently disabled, 4 pursued new occupations as a manual worker, 1 were still in therapy. Only two of the manual laborers were able to return to their preinjury occupation. Despite these unacceptable functional results, all patients were satisfied with the surgery.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2019년도 학술발표회
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• pp.151-151
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• 2019

Because drought is a complex and stochastic phenomenon in nature, statistical approaches for drought assessment receive great attention for water resource planning and management. Generally drought characteristics such as severity, duration and intensity are modelled separately. This study aims to develop a relationship between drought characteristics using a bivariate copula model. To achieve the objective, we calculated the Standardized Precipitation Index (SPI) using rainfall data at 6 rain gauge stations for the period of 1961-1999 in Jehlum River Basin, Pakistan, and investigated the drought characteristics. Since there is a significant correlation between drought severity and duration, they are usually modeled using different marginal distributions and joint distribution function. Using exponential distribution for drought severity and log-logistic distribution for drought duration, the Galambos copula was recognized as best copula to model joint distribution of drought severity and duration based on the KS-statistic. Various return periods of drought were calculated to identify time interval of repeated drought events. The result of this study can provide useful information for effective water resource management and shows superiority against univariate drought analysis.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2022년도 학술발표회
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• pp.158-158
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• 2022

Ecological drought consequences have received a lot of attention in recent years. Thus, ecological drought was proposed as a new drought category to characterize the impact of drought on ecosystems. The current study used a unique drought index, the standardized supply-demand water index (SSDI), and a run theory to detect ecological drought occurrences and characteristics such as drought-affected area, drought severity, drought duration, drought frequency, and drought orientation in the Hwang River, an environmentally valuable region. Hence, to assess drought-prone areas, the bivariate probability and return period will be calculated using a two-dimensional joint copula. The core results show that (a) the Spatio-temporal characteristics of ecological drought were successfully recognized using the spatial and temporal identification approach; (b) in comparison to the SPEI meteorological drought index, the SSDI is more credible and can more readily and effectively capture the entire properties of ecological drought information; (c) the Hwang river had seen the most severe drought occurrences between the late 1990s and the mid-2020s, with 48.3 percent occurring before the twenty-first century; (d) Severe ecological drought occurrences occurred more frequently in most areas of the Hwang River (e) Only the drought duration and severity in the Hwang area were more responsive to temperature when temperatures rise around 1.1℃, the average drought duration and severity rise around 16 % and 26 %, respectively. This suggested that the Hwang River has been exposed to more severe heat stress in the twenty-first century. Thereupon droughts in the twenty-first century occurred with bigger affected regions, longer durations, higher frequency, and more intensity.

• Archives of Reconstructive Microsurgery
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• 제11권2호
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• pp.167-172
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• 2002

The only treatment method for crushed soft tissue injuries in the proximal leg involving the knee joint is the microsurgical free flap transplantation, especially latissimus dorsi myocutaneous free flap is useful to cover the extensive soft tissue defects, therefore prevents iatrogenic below knee amputation and facilitates early wound healing, early ambulation and shortens hospital stay. Authors have treated the open amputation with crushed soft tissue and bone injuries in the proximal leg, and the repeated abrasion and infectious wound with traumatic neuroma in the below knee with myocutaneous free flap and succeeded to wear below knee amputation prosthesis and return to normal activities of the daily living in the relatively shorter period than usual.

• 한국조경학회지
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• 제36권4호
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• pp.111-119
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• 2008

합리식은 배수시설을 설계하기 위한 기본방정식으로 이용되고 있으며, 유출계수, 강우강도와 유역면적의 함수이다. 본 연구에서는 조경공간의 배수시설설계에 이용되는 합리식의 유출계수를 블록포장지역을 대상으로 지역적 강우분포를 고려하여 산정하였다. 합리식의 유출계수는 강우강도와 유출량의 비로 나타낼 수 있다. 강우강도는 재현기간과 강우지속기간의 함수로, 강우의 특성상 지역에 따라 변한다. 따라서 합리식의 유출계수는 동일한 재현기간과 강우지속기간일지라도 지역에 따라 강우강도가 변하므로 지역에 따라 변한다. 또한, 강우강도와 유출량의 비는 강우량에 대한 손실량에 따라 결정되므로, 손실량을 산정하기 위하여 본 연구에서는 Horton의 침투법칙 중 종기침투능을 이용하였다. 블록포장지역의 침투는 줄눈을 통하여 발생하며, 줄눈은 시간이 지남에 따라 황사, 오염물질, 꽃가루 등에 의하여 공극이 메워지고, 답압 등에 의하여 다져질 것이므로, 침투능은 감소할 것이다. 시공연한이 다른 6개 지역의 블록포장지역을 대상으로 Horton의 종기침투능을 산정하여 시간이 지남에 따라 침투능이 감소하는 것을 확인하였고, 지역별 재현기간 10년에 대한 강우지속기간 10, 20 및 30분에 해당하는 강우강도를 선정하여, 합리식의 유출계수를 산정하였다. 본 연구의 결과로, 산정 된 블록포장지 역의 유출계수 범위는 재현기간 10년, 강우지속기간 10분의 경우 지역에 따라 $0.94{\sim}0.84$의 범위를 가진다.

• 천문학회보
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• 제35권1호
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• pp.87.2-87.2
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• 2010

Near-Earth asteroid-comet transition object 4015 Wilson-Harrington is a possible target of the joint European Space Agency (ESA) and Japanese Aerospace Exploration Agency (JAXA) Marco Polo sample return mission. 4015 W-H was discovered showing cometary activity by Albert G. Wilson and Robert G. Harrington at Palomar Observatory in 1949. After recovered in 1979, 4015 W-H has been observed at every apparition, it always was seen as a point source. We made time series observations for 4015 W-H using the 1.8m telescope with 2K CCD at Bohyunsan Observatory, on the nights of 2009 November 17-19. The geocentric distance of 4015 H-W was about 0.38 AU at that time. No trace of cometary activity is seen from our images. From the light curve analysis, we find a double-peaked rotational period of 2.2 hours with amplitude of 0.4 magnitude. Our result is much shorter than previous measurements of 3.6 hours (Harris & Young 1983) and 6.1 hours (Osip et al 1995). We will discuss possible origin of the period variations.

• 콘크리트학회논문집
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• 제24권6호
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• pp.633-641
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• 2012

이 논문에서는 비탄성 시간이력해석을 통해 보-기둥 접합부 비탄성 전단거동이 구조물 거동에 미치는 영향을 알아보기 위해 지반조건 $S_B$ 내진설계범주 C에 대해서 5층 철근콘크리트 보통모멘트골조를 KBC2009에 맞게 구조설계 하였다. 보 및 기둥 부재의 휨모멘트-곡률 관계는 fiber model로 확인하였으며 보-기둥 접합부 모멘트-회전각 관계는 simple and unified joint shear behavior model과 보-기둥 접합부 모멘트 평형관계를 이용하여 확인하였다. 이력거동은 IDARC 프로그램의 three-parameter model을 활용하여 나타내었다. 2400년 재현주기 수준의 최대지반가속도에 대한 비탄성 시간이력해석 결과 비탄성 보-기둥 접합부를 고려하는 경우 최대밑면전단력은 감소하나 최대지붕층변위, 최대층간변위는 차이가 없었으며 발생한 최대층간변위도 KBC2009의 허용층간변위를 만족하여 구조설계 과정에서 보-기둥 접합부의 비탄성 전단거동을 고려하지 않아도 문제가 없을 것으로 판단된다.