Objective Assessment of Surgical Restaging after Concurrent Chemoradiation for Locally Advanced Pancreatic Cancer

백우현,이상협,김용태,박진명,송병진,류지곤 대한의학회 2015 Journal of Korean medical science Vol.30 No.7

The role of neoadjuvant chemoradiation therapy in locally advanced pancreatic cancer (LAPC) is still controversial. The aim of this study was to evaluate surgical downstaging after concurrent chemoradiation therapy (CCRT) for LAPC by measuring the objective changes after treatment. From January 2003 through July 2011, 54 patients with LAPC underwent neoadjuvant CCRT. Computed tomography findings of the tumor size, including major vessel invasion, were analyzed before and after CCRT. Among the total recruited patients, 14 had borderline resectable malignancy and another 40 were unresectable before CCRT. After CCRT, a partial response was achieved in four patients. Stable disease and further disease progression were achieved in 36 and 14 patients, respectively. Tumor size showed no significant difference before and after CCRT (3.6 ± 1.1 vs. 3.6 ± 1.0 cm, P = 0.61). Vessel invasion showed improvement in two patients, while 13 other patients showed further tumor progression. Thirty-nine patients with unresectable malignancy and 11 patients with borderline resectable malignancy at time of initial diagnosis remained unchanged after CCRT. Four patients with borderline pancreatic malignancy progressed to an unresectable stage, whereas one unresectable pancreatic malignancy improved to a borderline resectable stage. Only one patient with borderline resectable disease underwent operation after CCRT; however, curative resection failed due to celiac artery invasion and peritoneal seeding. The adverse events associated with CCRT were tolerable. In conclusion, preoperative CCRT in LAPC rarely leads to surgical downstaging, and it could lower resectability rates.

Double Injection Diode 의 부성저항기구(負性抵抗機構)에 대한 해석

백우현,성영권,김성진,함윤석 고려대학교 공학기술연구소 1984 고려대학교 생산기술연구소 생기연논문집 Vol.20 No.1

A Simple analysis of current-voltage characteristics of double injection diodes heavily doped and compensated with gold impurities is described by using the Regional Approximation Method, which was confined by the experiments compared with the exact numerical calculation. And the threshold voltage and criterion of negative resistance is also given through an approximation scheme which emphasizes the underlying physics of each regime.

황토의 재발견

백우현,Baek, U-Hyeon (사)한국원적외선협회 1998 한국원적외선협회보 Vol.1 No.-

Surface Tension of Molten Salts and Strong Electrolyte Solutions

백우현,성용길,전무식,Paek, Woo-Hyun,Sung, Yong-Kil,Jhon, Mu-Shik Korean Chemical Society 1970 대한화학회지 Vol.14 No.3

A theory of surface tension developed by using the approximation that the surface of liquids consists of a monomolecular layer has been applied to the molten salts (NaCl, KCl, NaBr, KBr) and the strong electrolyte solutions. By considering that the ionic forces are the long-range forces and with the use of the partition functions developed, the surface tension of molten salts and strong electrolyte solutions has been calculated. The results show good agreement between theory and experiment at various temperatures and over a wide concentration ranges (0.1-4.0m)

황토로 만든 기능성 종이 포장재 개발

백우현,Baek, U-Hyeon (사)한국포장협회 2006 包裝界 Vol.158 No.-

주거환경 개선을 위한 원적외선 복사체

백우현,Baek, U-Hyeon (사)한국원적외선협회 1998 한국원적외선협회보 Vol.2 No.-

생약제제의 GMP 현황

백우현 한국생약학회 1995 생약학회지 Vol.26 No.3

원적외선 방사체의 분광학적 특성에 관한 연구

白禹鉉 慶尙大學校 기초과학연구소 1990 基礎科學硏究所報 Vol.6 No.-

Hign efficiency far-infrared radiants similar to far-infrared radiation of black body were developed by ceramics made from mixtrue of several kinds of materials fired at 1150℃. Good results as high efficiency far-infrared radiants were obtained using natural stone as main materials and addition of transitional element oxide and clay ingredients as adjunct materials. Optical character of the ceramics powder was emissivity(ε) above 0.904 and emission wavelength about 10㎛.

액상화 재해지도를 이용한 수도권 전력구 매설지반의 지진시 위험도 평가

백우현,최재순,Baek, Woohyun,Choi, Jaesoon 한국방재안전학회 2019 한국방재안전학회 논문집 Vol.12 No.1

본 연구는 수도권 지역의 전력구 매설지반을 대상으로 지진 재현주기 1,000년을 고려한 최대기반암가속도 0.154g로 설정하여 지진시 위험을 평가하였다. 이때, 지진시 위험도 평가는 총 3단계로 진행하였으며 1단계는 대상지역의 지반조사 정보를 기초로 지반분류를 우선 실시한 후, 액상화 발생가능성을 파악할 수 있는 Macro영역 기법인 지반증폭계수를 이용한 액상화 발생가능지수(LPI, Liquefaction Potential Index) 재해지도를 이용하여 후보지를 선정한다. 2단계 위험도 평가는 1단계 평가에서 액상화 발생가능성이 매우 높게 판정된 전력구 주변의 시추주상도를 바탕으로 부지특성을 반영한 지진응답해석을 수행하고 이를 토대로 액상화 발생가능성 지수를 재산정하여 지진시 액상화 위험도를 상세평가 하였다. 3단계는 시추공자료를 기반으로 하는 한계성을 보완하기 위하여 2단계에서 액상화 발생가능성이 높게 평가된 대상 전력구의 현장조사를 실시하여 건설시 보강공법적용, 내진설계적용 및 현장상태 등을 고려하여 최종적으로 액상화 위험도를 평가하였다. In this study, the seismic risk has been evaluated by setting the bedrock acceleration to 0.154g which, was taking into consideration that the earthquake return period for the buried electric power tunnels in the metropolitan area to be 1,000 years. In this case, the risk assessment during the earthquake was carried out in three stages. In the first stage, the site classification was performed based on the site investigation data of the target area. Then, the LPI(Liquefaction Potential Index) was applied using the site amplification factor. After, candidates were selected using a hazard map. In the second stage, risk assessment analysis of seismic response are evaluated thoroughly after the recalculation of the LPI based on the site characteristics from the boring logs around the electric power area that are highly probable to be liquefied in the first stage. The third Stage visited the electric power tunnels that are highly probable of liquefaction in the second stage to compensate for the limitations based on the borehole data. At this time, the risk of liquefaction was finally evaluated based off of the reinforcement method used at the time of construction, the application of seismic design, and the condition of the site.

서울, 경기지역의 시나리오별 액상화 위험지도 작성을 위한 지진가속도와 LPI 상관관계 분석

백우현,최재순 한국지반환경공학회 2019 한국지반환경공학회논문집 Vol.20 No.5

On November 15, 2017, a unpredictable liquefaction damage was occurred at the ML = 5.4 Pohang earthquake and after, many researches have been conducted in Korea. In Korea, where there were no cases of earthquake damage, it has been extremely neglectable in preparing earthquake risk maps and building earthquake systems that corresponded to prevention and preparation. Since it is almost impossible to observe signs and symptoms of drought, floods, and typhoons in advance, it is very effective to predict the impacts and magnitudes of seismic events. In this study, 14,040 borehole data were collected in the metropolitan area and liquefaction evaluation was performed using the amplification factor. Based on this data, liquefaction hazard maps were prepared for ground accelerations of 0.06 g, 0.14 g, 0.22 g, and 0.30 g, including 200years return period to 4,800years return period. Also, the correlation analysis between the earthquake acceleration and LPI was carried out to draw a real-time predictable liquefaction hazard map. As a result, 707 correlation equations in every cells in GIS map were proposed. Finally, the simulation for liquefaction risk mapping against artificial earthquake was performed in the metropolitan area using the proposed correlation equations. 2017년 11월 15일 발생한 ML = 5.4의 포항지진으로 액상화 피해사례가 접수되었으며 이에 대한 많은 연구가 수행 중에 있다. 지진에 의한 피해사례가 전무하였던 우리나라의 경우, 예방 및 대비에 해당하는 지진위험지도 작성과 지진 및 지진해일 관측시스템의 구축에 매우 소극적이었다. 지진은 가뭄, 홍수나 태풍 등과 달리, 발생 징후를 관찰하고 그 영향 및 규모를 미리 예측하기란 거의 불가능에 가깝기 때문에 예방 및 대비차원의 액상화 위험지도와 같은 지진재해지도 구축은 매우 효과적일 수 있다. 본 연구는 수도권지역 14,040개의 시추공 데이터를 수집하여 지반증폭계수를 이용한 액상화 평가를 우선적으로 실시하고 최대기반암가속도는 재현주기 200년부터 4,800년을 포함하는 최대기반암가속도 0.06g, 0.14g, 0.22g, 0.30g에 대한 액상화 위험지도를 작성하였다. 또한, 실시간 예측 가능한 액상화 위험지도 작성을 위해 지진가속도와 상관관계 분석을 실시하였으며 그 결과로 수치지도의 모든 셀에 해당하는 상관식이 제안되었다. 최종적으로 제안된 상관식을 이용하여 가상의 지진에 대한 액상화 위험지도를 작성하였다.