사이클로이드 블레이드 시스템을 장착한 무인 수직이착륙 비행체 사이클로콥터

윤철용,박일경,김승조 한국항공우주학회 2004 한국항공우주학회 학술발표회 논문집 Vol.- No.-

전이 전립선암의 호르몬치료에 있어서 유리 전립선특이항원 추적관찰의 임상적 의의

윤철용 대한비뇨의학회 2006 Investigative and Clinical Urology Vol.47 No.4

무베어링 헬리콥터 주로터의 공력탄성학적 안정성 해석

윤철용,김태주,기영중,김덕관,김승호 한국항공우주학회 2011 한국항공우주학회 학술발표회 논문집 Vol.2011 No.11

본 논문에서는 무베어링 주로터에 대해 공력탄성학정 안정성 관점에서 현상을 분석하였다. 기본 로터 형상을 정의하고, 그 형상에 대해 모달 해석을 수행하여, 동특성을 확인하였다. 또한, 피치링크 장착방식에 따른 기하학적 피치-래그 연계가 공탄성 안정성에 미치는 영향성을 해석하였으며, 피치링크 강성이 피치 모드에 미치는 영향과 댐퍼 위치에 따른 면내 댐핑을 살펴보았다. 피치링크는 블레이드 시위방향으로 뒤전에서 토크듀브와 연결되었을 때 로터는 안정성이 확보되었으며, 음의 경사각을 갖도록 장착되면 고피치에서 면내 댐핑이 상당히 증대된다. 댐퍼는 유연보에 있는 유효 래그 힌지와 멀어지는 허브 중앙에 가까이 장착되면 댐퍼의 효과가 증대되어 안정성이 증가한다. This paper describes an aeroelastic stability of bearingless helicopter main rotor. Baseline rotor configuration is defined and modal analysis for the configuration is taken to verify the dynamic characteristics. The kinematic pitch-lag couplings through ways of pitch link installation are analyzed to know effects on aeroelastic stability. The effects of pitch link stiffness and damper positions on inplane damping are examined. Pitch link at trailing edge location in chordwise direction has influence on aeroelastic stability of the blades. Also, the pitch link with negative inclination makes inplane damping to increase at high pitch. It is good for damper to be located near the hub center.

압전 수동 댐퍼를 이용한 판의 진동 억제

윤철용,김승조 한국항공우주학회 2000 한국항공우주학회 학술발표회 논문집 Vol.- No.-

Sunitinib Malate Synergistically Potentiates Anti-Tumor Effect of Gemcitabine in Human Bladder Cancer Cells

윤철용,이정선,김보선,정성진,홍성규,변석수,이상은 대한비뇨의학회 2011 Investigative and Clinical Urology Vol.52 No.1

Purpose: Sunitinib malate (Sutent; Pfizer, New York, NY, USA) is a highly selective multi-targeted agent and has been reported to have potent anti-tumor effects against various tumors, including renal cell carcinoma and gastrointestinal stromal tumors. In this study, we explored in vitro the anti-tumor effect and related molecular mechanisms of sunitinib malate against human bladder cancer cell lines. We also determined the synergistic anti-tumor effect between sunitinib and conventional cytotoxic drugs, cisplatin and gemcitabine, in bladder cancer cells. Materials and Methods: Six human cancer cell lines (HTB5, HTB9, T24, UMUC14, SW1710, and J82) were exposed to an escalating dose of sunitinib alone or in combination with cisplatin/gemcitabine, and the cytotoxic effect of the drugs was examined by CCK-8 assay. The synergistic effect between sunitinib and cisplatin/gemcitabine was determined by the combination index (CI) and clonogenic assay. Alterations in cell cycle (cyclin D, B1), survival (p-Akt, t-Akt), and apoptosis (Bax, Bad) regulator expression were analyzed by Western blotting. Results: Like cisplatin and gemcitabine, sunitinib exerted a dose- and time-dependent anti-tumor effect in bladder cancer cells. However, sunitinib exhibited entirely different sensitivity profiles from cisplatin and gemcitabine. Sunitinib suppressed the expression of cyclin B1, p-Akt, and t-Akt while augmenting the expression of cyclin D and pro-apoptotic Bax and Bad in HTB5 cells. Analysis of the drug combination by the isobolic method and clonogenic assay revealed that sunitinib acts in synergy with gemcitabine in HTB5 cells. Conclusions: These results indicate that sunitinib malate has a potent anti-tumor effect and may synergistically enhance the anti-tumor effect of gemcitabine in human bladder cancer cells. Purpose: Sunitinib malate (Sutent; Pfizer, New York, NY, USA) is a highly selective multi-targeted agent and has been reported to have potent anti-tumor effects against various tumors, including renal cell carcinoma and gastrointestinal stromal tumors. In this study, we explored in vitro the anti-tumor effect and related molecular mechanisms of sunitinib malate against human bladder cancer cell lines. We also determined the synergistic anti-tumor effect between sunitinib and conventional cytotoxic drugs, cisplatin and gemcitabine, in bladder cancer cells. Materials and Methods: Six human cancer cell lines (HTB5, HTB9, T24, UMUC14, SW1710, and J82) were exposed to an escalating dose of sunitinib alone or in combination with cisplatin/gemcitabine, and the cytotoxic effect of the drugs was examined by CCK-8 assay. The synergistic effect between sunitinib and cisplatin/gemcitabine was determined by the combination index (CI) and clonogenic assay. Alterations in cell cycle (cyclin D, B1), survival (p-Akt, t-Akt), and apoptosis (Bax, Bad) regulator expression were analyzed by Western blotting. Results: Like cisplatin and gemcitabine, sunitinib exerted a dose- and time-dependent anti-tumor effect in bladder cancer cells. However, sunitinib exhibited entirely different sensitivity profiles from cisplatin and gemcitabine. Sunitinib suppressed the expression of cyclin B1, p-Akt, and t-Akt while augmenting the expression of cyclin D and pro-apoptotic Bax and Bad in HTB5 cells. Analysis of the drug combination by the isobolic method and clonogenic assay revealed that sunitinib acts in synergy with gemcitabine in HTB5 cells. Conclusions: These results indicate that sunitinib malate has a potent anti-tumor effect and may synergistically enhance the anti-tumor effect of gemcitabine in human bladder cancer cells.

전립선암의 예후인자로서 Gleason score와 호르몬 치료 후 전립선 특이 항원치의 변화에 대한 연구

윤철용,조재흥 大韓泌尿器科學會 1998 Korean Journal of Urology Vol.39 No.5

BO-105 블레이드를 장착한 무베어링 주 로터의 훨타워 시험

윤철용,기영중,송근웅,김승범,김덕관,백승길 한국항공우주학회 2014 한국항공우주학회 학술발표회 논문집 Vol.2014 No.4

본 논문은 회전반경 5.82m, 4개의 BO-105 블레이드를 가지는 무베어링 로터의 정지비행 훨타워 회전시험에 관해 기술하였다. 유연보, 토크튜브와 스너버로 구성된 무베어링 로터 허브를 제작하여 조립하였고, 회전시험을 수행하기전 기본물리량 시험, 구조시험, 피로시험등 지상시험을 수행하였다. 회전시험을 위한 무베어링 로터의 회전면 높이는 9.65m이며, 하중 및 동특성 측정을 위해 스트레인 게이지를 부착하였고, 추력 및 파워는 3축 하중 밸런서를 이용하여 측정하였다. 훨타워 회전시험을 통해 무베어링 로터의 정지비행 성능, 회전 고유진동수 및 감쇠, 블레이드 단면의 구조 하중을 측정하였으며, 그 측정 결과를 해석 결과와 비교하였다. This paper describes the whirl tower rotation test of 4 BO-105 bladed bearingless main rotor with 5.82m rotor radius in hover. The bearingless rotor hub composed of flexbeam, torque tube and snubber is manufactured and assembled and the ground test such as basic properties test, structural test, and fatigue test was conducted before the whirl tower test. The height of test rotor rotation plane from the ground is 9.65m. The strain gages are used to measure the structural loads and stability, and the rotor thrust and power are measured by using 3-axis load balancer. The measurement values for hover performance, rotation frequency, damping, and loads are compared to analysis results. The test results agree well with analysis results.

특집/전립샘암의 병인

윤철용,변석수 대한의사협회 2010 대한의사협회지 Vol.53 No.2

Prostate cancer is one of the most frequent cancers in Western countries and has been also one of the most rapidly increasing malignant diseases in Korean men. This disease shows diverse features in clinical course ranging from an indolent disease to a lethal one. Accordingly,underlying molecular mechanisms and genetic changes involved in the development and progression of various types of prostate cancer are very heterogeneous. Thus, investigation of pathogenesis of prostate cancer is very challenging, and, at this point of time, only a handful of molecular and genetic factors were identified as pathogenic factors for prostate cancer. Plenty of data support the strong relationship between age, race and family history and the development of prostate cancer. In addition, androgen related factors such as androgen metabolism and receptor signaling are highly correlated with tumor development and progression. Numerous genetic or epigenetic changes including gene mutation and methylation contribute to the development and progression of prostate cancer. In this article, we summarize the current understanding of the pathogenesis of prostate cancer, with a special focus on underlying genetic and epigenetic alterations.

Sulfated Glycoprotein-2 (Clusterin)가 전립선암의 세포고사에 미치는 영향

윤철용,조재흥,원남희 大韓泌尿器科學會 2001 Korean Journal of Urology Vol.42 No.7

평활근에 대한 Tiropramide 및Propiverine HCI (BUP-4)의 수축 억제 효과: 흰쥐의 방광근육절편을 이용한 실험

윤철용,이동수,이정구 大韓泌尿器科學會 1997 Korean Journal of Urology Vol.38 No.5