후두미세수술 후 음향지표의 변화와 환자의 만족도 비교

김범석,신지훈,김기용,이용섭,김경래,태경,Kim, Bum-Suk,Shin, Ji-Hun,Kim, Ki-Yong,Lee, Yong-Seop,Kim, Kyung-Rae,Tae, Kyung 대한후두음성언어의학회 2008 대한후두음성언어의학회지 Vol.19 No.2

Background and Object: The aim of this study is to evaluate the change of patient's subjective voice handicap index (VHI) and acoustic parameters before and after laryngeal microsurgery for benign vocal cord disease. Materials and Method: We analyzed 78 patients who received laryngeal microsurgery for benign vocal cord disease from January 2004 to February 2007 retrospectively. There were 28 vocal polyp, 40 vocal nodule, 5 intracordal cyst and 5 Reinke's edema. Jitter, shimmer, harmony to noise ratio (HNR) were analyzed before surgery and 2-3months after surgery using the Doctor's speech science program. The voice handicap index introduced by the Pittsburgh Voice Center was used to examine patient's subjective change of voice quality. Results: Acoustic parameters of jitter, shimmer and HNR were improved in patients with vocal polyp and vocal nodule after surgery. The acoustic parameters were not improved in patients with Reinke's edema, statistically. Only jitter was improved significantly in patients with intracordal cyst (p<0.05). The VHI was significantly improved after surgery. The change of jitter and shimmer was significantly correlated with the change of VHI after surgery. Conclusion: The acoustic parameters and VHI were significantly improved in patients with benign vocal disease after laryngeal microsurgery.

육안과 분광 측정기를 이용한 자연 치아의 색조비교분석

김범석,신수연,이종혁,Kim, Bum-Suk,Shin, Soo-Yeon,Lee, Jong-Hyuk 대한치과보철학회 2008 대한치과보철학회지 Vol.46 No.5

도재 수복물 제작을 위해 자연치아의 색조를 분석하는 방법으로는 색견본 (shade guide)을 이용하는 시각적인 방법과 기계를 이용하는 방법이 있다. 그중 통상적인 육안 관찰을 통해 색조를 선택하는 것은 임상에서 가장 많이 이용되고 있는 방법이기는 하나 주관적이며 일관되지 않은 결과로 신뢰성의 문제가 제기되었으며 자연치의 색조는 매우 다양하여 같은 치아라 할지라도 부위별로 다양한 색조를 가지기 때문에 단순히 shade tab을 이용한 색조 비교만으로는 정확한 치아의 색조 특성을 나타내는 것이 불가능한 것으로 알려져 있다. 한편 지속적인 기술발달로 computer color matching system, 치과용 비색계, 분광 측정기 등의 기계를 이용한 치아 색조 측정 방법이 이의 대안으로 제시되고 있다. 기계를 이용한 방법은 색조 선택에 있어 객관적이며, 재현성이 있는 정확한 정보를 술자에게 제공한다. 이에 본 연구에서는 광원, 개인, 술자의 숙련도에 따라 육안과 기계를 통한 관찰 시 치아 색조 선택의 정확성을 확인하기 위한 실험을 시행하였다. 첫 번째 실험에서는 치과대학병원 전공의인 1명의 검사자가 10명의 피검자를 오전, 정오, 오후 각 3번의 측정을 통해 시간대별 자연광하에 육안, 기계 측정의 색조 선택 정확성을 분석하였다. 두 번째 실험에서는 5명의 치과대학병원 전공의와 5명의 치과대 학생, 총 10명의 검사자가 10명의 피검자를 정오에 육안, 기계 관찰을 통해 개인차에 따른 정확성을 실험하였다. 세 번째 실험에서는 두 번째 실험의 결과를 5명의 치과대학 전공의, 5명의 치과대학생 군으로 나누어 숙련도에 따른 육안, 기계 색조 선택의 정확성을 분석하였다. 실험 결과, 첫 번째 실험에서는 기계 측정 결과가 육안 측정보다 통계적으로 유의한 차이를 보이며 (P < .05) 색조 선택의 정확성을 나타내었고, 두 번째 실험에서 역시 기계 측정시 개개인의 육안 측정에 의한 색조 선택 값에 비해 재현성 및 정확성이 높았으며 통계적으로 유의한 차이를 보였다 (P < .05). 세 번째 실험에서 이전 실험의 결과를 숙련자, 비숙련자 군으로 나누어 분석한 결과 군 내 기계 측정값이 육안 관찰값보다 숙련도에 상관없이 정확도가 높으며 통계적으로 유의한 차이를 보였다 (P < .05). 하지만 군 간 육안, 기계 측정값을 비교 시 통계적으로 유의한 차이를 보이지 않아 치아 색조를 육안, 기계 측정할 때 술자의 숙련도가 큰 영향을 미치지 않음을 알 수 있었다. 따라서 기계를 이용하는 치아 색조 측정 방법이 색견본을 이용하는 시각적인 방법에 비해 더 정확하기는 하지만 어느 정도의 측색 오류를 고려해야하며 수복물 제작 시 정확한 재현과 효과적인 정보 전달을 위해 시각적인 방법과의 병행이 필요할 것으로 사료된다. Statement of problem: A clinically successful color match is one of the important factor to get an esthetic dental restoration. Dental shade guides are commonly used to evaluate tooth color in restorative procedure. But numerous reports have indicated that common shade guides do not provide sufficient spectral coverage of the natural tooth colors. To address issues associated with the shade guide, distinct avenues have been pursued objective spectrophotometric / colorimetric assessment. Purpose: This study compared the accuracy of tooth color selection of spectrophotometer with that of human visual determination. Three main factors were investigated, namely, the effect of light, the individual variation and the experience of the observer. Material and methods: At the first experiment, on ten patients, one operator independently selected the best matching shade to the unrestored maxillary central incisor, using a Vita Classical Shade Guide in the morning, at noon and in the afternoon. The same teeth were measured by means of a reflectance spectrophotometer. At the second experiment, on ten patients, ten operators (5 experts, 5 novices) selected and measured by the same method above at noon. At the third experiment, the results of the second experiment were divided into two groups, expert and novice, and analyzed. Results: 1. There was significant difference between visual and spectrophotometric assessment (mean ${\Delta}E$ values) in experiment 1, 2, 3 (P < .05). 2. There was no significant difference between experts and novices group, when comparing with each visual and spectrophotometric assessment (mean ${\Delta}E$ values). Conclusion: Spectrophotometer could be used to analyze the shade of natural tooth objectively. Thereby, this method offers the potential tominimize considerably the need for corrections or even remakesafter intraoral try-in of restoration. Furthermore, to achieve its advantage, both the shade-matching environment and communication between dentist and technician should be optimized with use of visual and instrumental shade-matching systems.

BEMT에 의한 100kW 풍력터빈 블레이드 기본설계 및 출력 성능해석

김범석,김만응,이영호,Kim, Bum-Suk,Kim, Mann-Eung,Lee, Young-Ho 한국마린엔지니어링학회 2008 한국마린엔지니어링학회지 Vol.32 No.6

In this study, mathematical expressions based upon the conventional BEMT(blade element momentum theory) was applied to basic 100kW wind turbine blade configuration design. Power coefficient and related flow parameters, such as Prandtl's tip loss coefficient, tangential and axial flow induction factors of the wind turbine were analyzed systematically. X-FOIL was used to acquire lift and drag coefficients of the 2-D airfoils and Viterna-Corrigan formula was used o interpolate he aerodynamic characteristics in post-stall region. Also, aerodynamic characteristics, measured in a wind tunnel to calculate he power coefficient was applied. The comparative results such as axial and tangential flow factors, power coefficients were presented in this study. Power coefficient, calculated by in-house code was compared with the GH-Bladed result. The difference of the aerodynamic characteristics caused the difference of the performance characteristics as variation as TSR.

Branched - chain Fatty Acids 가 반추위 (反芻胃) 미생물의 성장과 소화율 및 VFA 생성에 미치는 영향

김범석,맹원재 ( Bum Suk Kim,Won Jae Maeng ) 한국낙농학회 1989 韓國酪農學會誌 Vol.11 No.1

역동성의 정치경제

김범석(Bum Suk Kim) 21세기정치학회 2012 21세기 정치학회보 Vol.22 No.1

The purpose of this study is to analyze the changing patterns of the South Korean developmental model based on the perspective of the historical institutionalism. After the East Asian financial crisis in 1997, this study examines the South Korean case by focusing on the financial sector, governmentbusiness relations, and information policy. It investigates what specific reform measures had taken, how financial system and corporate system had been changed, and the changed role of the state. The main argument of this study is that the historical legacy of the developmental state in South Korea remains strong although the overall direction is drifting toward the Anglo-American neo-liberal model.

동적 평형위치에 있는 다물체계의 모드특성에 미치는 공차의 영향 분석을 위한 해석적 방법

김범석(Kim, Bum-Suk),유홍희(Yoo, Hong-Hee) 한국소음진동공학회 2007 한국소음진동공학회 논문집 Vol.17 No.7

Analytical method to analyze the effect of tolerance on the modal characteristic of multi-body systems in dynamic equilibrium position is suggested in this paper. Monte-Carlo method is conventionally employed to perform the tolerance analysis. However, Monte-Carlo method spends too much time for analysis and has a greater or less accuracy depending on sample condition. To resolve these problems, an analytical method is suggested in this paper. Sensitivity equations for damped natural frequencies and the transfer function are derived at the dynamic equilibrium position. By employing the sensitivity information of mass, damping and stiffness matrices, the sensitivities of damped natural frequencies and the transfer function can be calculated.

동아시아 지역통합의 정치경제

김범석(Bum Suk Kim) 21세기정치학회 2007 21세기 정치학회보 Vol.17 No.2

This study attempts to examine the political impact on cross-strait relations of growing cross-strait economic interaction. Cross-strait economic interaction continues to deepen while political and security tensions are rising. The economic complementary provides strong incentives for deeper economic integration. This economic integration will not only raise the cost of military conflict, but also create interest groups that have a strong interest in stability of cross-strait relations. Taiwan independent movement will weaken as cross-strait economic exchanges expands. China also will relax its military posture against Taiwan as Taiwan independent movement weakens. Therefore, as the main sources of regional instability will fade, the new and cooperative cross-strait relations will be realized in the near future.

CFD 기법을 활용한 3㎿ 풍력터빈 블레이드 성능평가

김범석(Bum-Suk Kim),김우준(Woo-June Kim),김만응(Mann-Eung Kim) 한국유체기계학회 2009 유체기계 연구개발 발표회 논문집 Vol.2009 No.-

2 ㎿급 풍력터빈 블레이드 설계 및 단방향 유체-구조연성해석

김범석(Bum-suk Kim),이강수(Kang-su Lee),김만응(Mann-eung Kim) 대한기계학회 2009 大韓機械學會論文集B Vol.33 No.12

The purposes of this study are to evaluate the power performance through CFD analysis and structural integrity through uni-directional FSI analysis in aerodynamic design and structure design of wind turbine blade. The blade was designed to generate the power of 2㎿ under the rated wind speed of 11 ㎧, consisting of NACA 6 series, DU series and FFA series airfoil. The inside section of the blade was designed into D-spar structure and circular stiffener was placed to reinforce the structural strength in the part of hub. CFD analysis with the application of transitional turbulence model was performed to evaluate the power performance of blade according to the change of TSR and 2.024㎿ resulted under the condition of rated wind speed. TSR of 9 produced the maximum power coefficient and in this case, Cp was 0.494. This study applied uni-directional FSI analysis for more precise evaluation of structural integrity of blade, and the results of fiber failure, inter fiber failure and eigenvalue buckling analysis were evaluated, respectively. For the evaluation, Puck’s failure criteria was applied and the result showed that fiber failure and inter fiber failure did not occur under every possible condition of the analysis. As a result, power performance and structural integrity of 2 ㎿ blade designed in this study turned out to satisfy the initial design goals.

난류모델 변화에 따른 수평축 풍력터빈 유동해석 및 출력성능 예측

김범석(Bum-suk Kim),음학진(Hark-jin Eum),원종범(Jong-bum Won),김만응(Mann-eung Kim) 대한기계학회 2008 대한기계학회 춘추학술대회 Vol.2008 No.5

Despite of the laminar-turbulent transition region co-exist with fully turbulence region around the leading edge of an airfoil, still lots of researchers apply to fully turbulence models to predict aerodynamic characteristics. It is well known that fully turbulent model such as standard k-model couldn't predict the complex stall and the separation behavior on an airfoil accurately, it usually leads to over prediction of the aerodynamic characteristics such as lift and drag forces. So, we apply correlation based transition model to predict aerodynamic performance of the NREL (National Renewable Energy Laboratory) Phase Ⅳ wind turbine. And also, compare the computed results from transition model with experimental measurement and fully turbulence results. Results are presented for a range of wind speed, for a NREL Phase Ⅳ wind turbine rotor. Low speed shaft torque, power, root bending moment, aerodynamic coefficients of 2D airfoil and several flow field figures results included in this study. As a result, the low speed shaft torque predicted by transitional turbulence model is very good agree with the experimental measurement in whole operating conditions but fully turbulent model(k-ε) over predict the shaft torque after 7m/s. Root bending moment is also good agreement between the prediction and experiments for most of the operating conditions, especially with the transition model.