Fractional microneedling radiofrequency 치료의 안면 주사에 대한 임상적 및 조직학적 효과 연구

학위논문 (석사)-- 서울대학교 대학원 : 임상의과학과, 2016. 2. 서대헌.Introduction: Fractional microneedling radiofrequency (FMR) is an emerging treatment modality, but its effect on rosacea has not been studied.We sought to investigate the potential impact of FMR treatment on clinical improvement and histological changes in rosacea patients. Methods: A 12-week, prospective, randomized, split-face clinical trial was conducted. Two sessions of FMR were performed on one side of the face witha 4-week interval between treatment sessions, and the other side of the face remained untreated. Clinical evaluation and photometricmeasurement of erythema and histologic analysis of skin samples werecarried out. Results: Clinical evaluation and photometric measurement revealed reduction of redness on the treated side compared with the untreated side and baseline. The erythema index decreased 13.6% and the a* value decreased 6.8% at week 12 compared with baseline. Reduced expression of markers related to inflammation, innate immunity, and angiogenesis was observed in the immunohistochemical staining of tissue obtained after FMR treatment. Conclusions: FMR can result in clinical and histological improvement of rosacea, and it can be used as an alternative or in combination with other treatment methods.LIST OF ABBREVIATIONS 1 INTRODUCTION 2 MATERIALS AND METHODS 4 1. Study design and subjects 4 2. Devices and laser treatment 4 3. Clinical outcome assessment 5 4. Histopathology and immunohistochemistry 6 5. Statistical analyses 7 RESULTS 9 Clinical improvement and safety 9 Patients subjective assessment 13 Histologic findings 14 DISCUSSION 18 REFERENCES 23 국문 초록 28Maste

(A)Didactical analysis on the mathematical induction

학위논문(박사)--서울대학교 대학원 :수학교육과,2008.2.Docto

방위산업체의 활동기준원가 도입 활용에 관한 연구

학위논문(석사)--서울대학교 대학원 :협동과정 기술정책전공,2006.Maste

교차오염 냉매 분리를 위한 증류 컬럼 설계

Master본 연구에서는 다양한 교차오염 냉매 분리를 위한 컬럼을 설계하였다. 본 연구를 통해, 단일컬럼으로 R134a(80wt%)/R12(20wt%), R134a(90wt%)/ R12(10wt%), R410a(80wt%)/R22(20wt%), R410a(90wt%)/R22(10wt%) 총 4가지 경우의 교차오염 냉매 분리가 가능하도록 설계 및 제작완료 하였다. 실질적으로 시뮬레이션 결과를 바탕으로 조업한 결과 고순도 냉매 분리 순도 99.5wt% 이상 완료 하였다. T-xy digram을 통해 교차오염 냉매의 분리 정도를 사전에 확인하였지만, 정확한 연속식 컬럼 설계를 위해 회분식 컬럼을 이용하여 우선적으로 다수의 교차오염 냉매 분리 실험을 완료하였다. 실험을 통해 얻은 결과를 바탕으로 연속식 컬럼 설계 시뮬레이션에 반영하였다. 또한, 정확한 열역학 모델 선정을 위하여 각 냉매에 대한 상평형 데이터 구축을 위해 직접 실험을 하였다. 또한, 교차오염 냉매의 총 4가지 경우에 대한 컬럼 시뮬레이션 결과 및 Hydraulic 분석을 통해 컬럼에 대한 전반적인 부분을 설계할 수 있었으며, 이를 통해 컬럼내 설치되는 충진재 선정도 하였다. 다양한 시뮬레이션과 실험을 바탕으로 Random Packing(HETP:296mm), Feed Stage 28, Column Stage 49, Column Diameter 0.25m 컬럼 설계완료 및 제작하였다. 향후에는, 차량용 냉매로 사용되는 R134a/R12 교차오염냉매보다는 R134a/R1234yf 교차오염냉매 발생이 예상된다. 현재 분별증류 기술로는 R134a/R12 교차오염 냉매와는 달리 R134a/R1234yf 교차오염 냉매는 분리할 수 없다. 따라서, 추후에 하이드레이트 공법을 적용하여 R134a/R1234yf 교차오염 냉매를 분리하고자 한다.In this study, a column was designed for the separation of various cross-contaminated refrigerants. Through this study, a total of four cases of cross-contamination can be designed and prepared for the manufacture and completion of intercooling of R134a(80wt%)/R12(20wt%), R134a(90wt%)/R12(10wt%), R410a(80wt%)/R22(10wt%) in a single column. The results of operation based on the simulation results show that the purity of separation of high purity refrigerant is greater than 99.5wt%. Although the degree of separation of cross-contaminated refrigerant was verified in advance through T-xy digram, a number of cross-contaminated refrigerant separation experiments were first completed using the diffraction column for accurate continuous column design. Based on the results obtained from the experiment, it was reflected in the continuous column design simulation. In addition, the experiment was conducted directly for the establishment of the top-level data for each refrigerant to select an accurate thermodynamic model. The column simulation results and the hydrological analysis of the total four cases of cross-contaminated refrigerant allowed the overall part of the column to be designed and the filling materials installed in the column were selected. Based on various simulations and experiments, Random Packing (HETP:296mm), Feed Stage 28, Column Stage 49, Column Diameter 0.25m Column Design was completed and built. In the future, it is expected that R134a/R1234yf cross-contaminated refrigerant will occur rather than R134a/R12 cross-contaminated refrigerant used as a vehicle refrigerant. Unlike R134a/R12 cross-contaminated refrigerant, R134a/R1234yf cross-contaminated refrigerant cannot be separated with the current sensible distillation technology. Therefore, it is recommended to separate the R134a/R1234yf cross-contaminated refrigerant by applying the hydrate technique at a later date