초음파 백내장쪼개기와 작은 백내장쪼개기에 의한 백내장 수술의 비교

김덕수,김명준,김재용,차흥원,Deok-Soo Kim,Myoung-Joon Kim,Jae-Yong Kim,Hung-Won Tchah 대한안과학회 2005 대한안과학회지 Vol.46 No.11

Purpose: To compare effective phacoemulsification time (EPT), the severity of corneal swelling and corneal endothelial cell density after cataract surgery between the phaco chop method and the mini chop method. Methods: Cataract surgery was performed by phaco chop (15 eyes) or by mini chop (13 eyes) method in 28 eyes of 27 patients. The nuclear opacity of cataract grade was more than 5 on LOCS (Lens opacities classification system) III. EPT and the amount of irrigated BSS solution were measured during the operation. Corneal thickness (preoperative, immediate postoperative, postoperative 1 day, 1 week, 1 month, and 3 months) and corneal endothelial cell density (preoperative, postoperative 1month and 3 months) were measured. Results: The EPT of phaco chop group was 5.2 sec and that of mini chop was 1.0 sec (p=0.000). The amount of irrigated BSS was 193.7 ml and 170.4 ml in the phaco chop group and the mini chop group, respectively. The increase in corneal thickness was 3.2% and 0.9% at immediately after surgery (p=0.128), 19.0% and 10.5% at postoperative 1 day (p=0.088), 5.7% and 1.5% at postoperative 1 week (p=0.080), 0% and -1.3% at postoperative 1 month (p=0.717), and -0.4% and -0.6% at postoperative 3 months (p=0.890) in the phaco chop group and the mini chop group, respectively. Corneal endothelial cell density decreased 23.0% in the phaco chop group and 9.4% in the mini chop group at postoperative 1 month (p=0.005) and 22.9%, 12.6%, at 3 months respectively (p=0.036). Conclusions: The mini chop technique reduced permanent endothelial cell damage in comparison with the phaco chop method and might be more effective in decreasing corneal swelling during the early postoperative period than the phaco chop method.

내관(PC-6) 및 위유(BL-21)의 자침 및 수침이 xylazine을 투여한 개에 미치는 구토 억제효과

김덕수,유건주,이정연,김명철,신상태,김덕환,Kim, Duck-Soo,Liu, Jianzhu,Lee, Jung-Yeon,Kim, Myung-Cheol,Shin, Sang-Tae,Kim, Duck-Hwan 대한수의학회 2005 大韓獸醫學會誌 Vol.45 No.3

This study was performed to elucidate the effect of acupuncture and aqua-acupuncture in dogs. Each group was divided into control (18 dogs), PC-6 (6 dogs) and BL-21 (6 dogs) group for the antiemetic effect of acupuncture, respectively. And, the animals were divided into control (18 dogs), PC-6 (18 dogs) and BL-21 (18 dogs) group for the antiemetic effect of aqua-acupuncture with metoclopramide, respectively. 2% xylazine was injected to the all dogs to induce the emesis, and acupuncture and aqua-acupuncture treatment (0.5% metoclopramide) were applied to animals for 20 min. before xylazine injection, respectively. Emetic rates in PC-6 (33.3%) and BL-21 (16.7%) were lower than that of control group (44.4%) in acupuncture groups, respectively. Emetic rates in PC-6 (16.7%) and BL-21 (0.0%) were lower than that of control group (38.9%) in aqua-acupuncture groups, respectively. Based on these findings, it was considered that the antiemetic effects of acupuncture and aqua-puncture at BL-21 were more effective than those of PC-6 groups, and aqua-acupuncture with metoclopramide at BL-21 was the most effective among them.

EMBR을 이용한 연주공정에서의 난류유동 및 응고에 대한 연구

김덕수,김우승,Kim, Deok-Soo,Kim, Woo-Seung 대한기계학회 1999 大韓機械學會論文集B Vol.23 No.3

Two-dimensional turbulent fluid flow and solidification were investigated in a continuous casting process of a steel slab with electromagnetic field. The electromagnetic field was described by the Maxwell equations. The enthalpy-porosity relation was employed to suppress the velocity within a mushy region. A revised low-Reynolds number $k-{\varepsilon}$ turbulence model was used to consider the turbulent effects. It is shown that the temperature gradient in the casting direction in the case with EMBR becomes very weak compared to that of the case without EMBR. The results also show that the velocity profiles of the case with solidification are quite different from those of the case without solidification.

볼류트 형상이 원심 펌프의 성능에 미치는 영향에 대한 수치 해석적 연구

김덕수,전상규,윤준용,최영석,Kim, Deok-Su,Jeon, Sang-Gyu,Yoon, Joon-Yong,Choi, Young-Seok 한국유체기계학회 2006 한국유체기계학회 논문집 Vol.9 No.2

In this study, the effects of volute area distribution on the performance of a centrifugal pump were numerically studied using a commercial CFD code. To reduce the shutoff head, maintaining head and efficiency at a design flow rate, the flat head-capacity characteristic curves in which the head varies only slightly with capacity from shutoff to design capacity are frequently required. In order to control the shutoff head of a pump, several volute cross-sectional area distributions were proposed as a main parameter with the same impeller geometry The calculation results show that the slope of the performance characteristic curve of the centrifugal pump can be controlled by modifying the area distribution from volute tongue to volute outlet with fixed volute outlet area and also varied volute outlet area.

쌍롤식 연속주조공정에서의 난류유동 및 거시적응고 해석

김덕수,김우승,조기현,Kim, Deok-Su,Kim, U-Seung,Jo, Gi-Hyeon 대한기계학회 2001 大韓機械學會論文集B Vol.25 No.3

The transport phenomena in a wedge-shaped pool of twin-roll continuous caster are affected by the various operating parameters such as the melt-feed pattern, roll-gap thickness, melt-superheat, and casting speed. A computer program has been developed for analyzing the two-dimensional, steady conservation equations for transport phenomena during twin-roll continuous casting process in order to estimate the turbulent melt-flow, temperature fields, and solidification in the wedge-shaped pool. The turbulent characteristics of the melt-flow were considered using a low-Reynolds-number K-$\xi$ turbulence model. Based on the computer program, the effects of the different melt-feed patterns, roll-gap thicknesses, and superheats of melt on the variations of the velocity and temperature distributions, and the mushy solidification were examined. The results show that the liquidus line is located considerably at the upstream region, and in the lower region appear the well-mixed melt-flow and most widely developed mushy zone. Besides, the variation of melt-flow due to varying melt-feed patterns, affects mainly the liquidus line, and scarcely has effects on the solidus line in the outlet region.

Voronoi diagram as an analysis tool for spatial properties for ceramics

김덕수,정용재,JayJ.Kim,김동욱,윤광석 한양대학교 세라믹연구소 2002 Journal of Ceramic Processing Research Vol.3 No.3

While research in ceramics has focused on physical experiments, the need for computational aids is increasing more and more. Among several computer simulation tools for the design and analysis of various aspects of ceramics, the Voronoi diagram is introduced in this paper. The Voronoi diagram is a powerful tool in computational geometry which provides all spatial information among geometric objects in a system with an efficient data structure. In this paper, we present the properties of Voronoi diagrams and introduce various applications appropriate for research in ceramics.

코눈물관 부분폐쇄 치료시 마이토마이신 관류 여부에 따른 실리콘관 삽입술의 효과

김덕수,이용재.Deok Soo Kim. M.D.. Yong Jae Lee. M.D. 대한안과학회 2006 대한안과학회지 Vol.47 No.2

Purpose: To investigate the efficacy and safety of adjunctive Mitomycin C (MMC) during silicone intubation (SI) for treatment of acquired incomplete nasolacrimal duct obstruction (NLDO). Methods: Nineteen eyes with incomplete NLDO underwent SI only (group I). 20 different eyes were administered adjunctive 0.4 mg/ml MMC for 4 minutes (group II). Diagnosis of incomplete NLDO was based upon subjective complaints of tearing, dye disappearance testing, clinical evidence of epiphora, and nasolacrimal duct irrigation. Follow-up examination was conducted at 1, 3, and 6 months. Results: Follow-up ranged from 3 to 15 months (mean, 6.1 months). Twelve (63.1%) eyes in group I and 14 (70.0%) eyes in group II had a successful outcome and remained symptom-free. Four (21.1%) eyes in group I and three (15.0%) eyes in group II showed improvement but still experienced periodic epiphora. The difference was not statistically significant (p=0.873). Conclusions: SI as a treatment for incomplete NLDO provides complete relief or substantial improvement in a significant percentage of patients but MMC application during SI did not benefit outcome.

해외동향분석-일본 기술력의 근원과 일본 기술의 특성

김덕수,Kim, Deok-Su 과학기술정책연구원 1995 과학기술정책 Vol.- No.78

FTES/$O_2$-PECVD 방법에 의한 SiOF 박막형성

김덕수,이지혁,이광만,강동식,최치규,Kim, Duk-Soo,Lee, Ji-Hyeok,Lee, Kwang-Man,Gang, Dong-Sik,Choe, Chi-Kyu 한국재료학회 1999 한국재료학회지 Vol.9 No.8

FTES/$O_2$-PECVD 방법에 의하여 증착된 SiOF 박막의 특성을 FT-IR, SPS, 그리고 ellipsometry로 분석하였다. 유전상수, breakdown field와 누설전류 밀도는 MIS(Au/SiOF/p-Si) 구조로 형성하여 C-V와 I-V특성곡선으로부터 측정하였다. SiOF박막의 step-coverage는 SEM 단면사진으로 조사하였다. FTES와 $O_2$의 유량을 각각 300sccm으로 반응로에 주입하였을 때 양질의 SiOF 박막이 형성되었다. 형성된 박막의 유전상수는 3.1로서 다른 산화막보다 더 낮은 값으로 나타났다. breakdown field와 누설전류밀도는 약 10MV/cm와 $8{\times}10^{9}A/\textrm{cm}^2$로 측정되었다. $0.3{\mu}{\textrm}{m}$ 금속 패턴에 $2500{\AA}$의 두께로 증착된 SiOF 박막은 전극간에 void가 없이 우수한 덮힘을 보였다. Characteristics of SiOF films deposited by a FTES/$O_2$-plasma enhanced chemical vapor deposition method have been investigated using Fourier transform infrared spectroscopy, X-ray photoelectro spectroscopy, and ellipsometry. Electrical properties such as dielectric constant, dielectric breakdown and leakage current density are investigated using C-V and I-V measurements with MIS(Au/SiOF/p-Si) capacitor structure. Stepcoverage of the films have been also characterized using scanning electron microscopy and ellipsometry. A high quality SiOF film was formed on that the flow rates of FTES and $O_2$were 300sccm, respectively. The dielectric constant of the deposited SiOF film was about 3.1. This value is lower than that of the oxide films obtained using other method. The dielectric breakdown field and leakage current are more than 10MV/cm and about $8[\times}10^{9}A/\textrm{cm}^2$, respectively. The deposited SiOF film with thickness as $2500{\AA}$ on the $0.3{\mu}{\textrm}{m}$ metal pattern shows a high step-coverage without a void.

칼슘 및 탈륨 이온으로 치환된 제올라이트 A, $Ca_xTl_{12-2x}-A$ (x = 1.4 및 5.6)를 탈수한 결정구조

김덕수,송승환,김양,Kim Duk Soo,Song Seong Hwan,Kim, Yang Korean Chemical Society 1993 대한화학회지 Vol.37 No.1

Two crystal structures of fully dehydrated Ca(II) and Tl(I) exchanged zeolite A, $Ca_{5.6}Tl_{0.8}-A (a = 12.242(2){\AA})\;and\;Ca_{1.4}Tl_{9.2}-A (a = 12.191(1){\AA})$, have been determined by single-crystal X-ray diffraction methods in the cubic space group Pm3m at 21(1)$^{\circ}C$. All crystals were ion exchanged in flowing streams of mixed $Ca(NO_3)_2\;and\;TINO_3$ aqueous solution with total concentration of 0.05M. All crystals were dehydrated at 360$^{\circ}C$ under $2{\times}10^{-6}\;torr$ for two days. The structures of the dehydrated $Ca_{5.6}Tl_{0.8}-A$ and $Ca_{1.4}Tl_{9.2}-A$ were refined to the final error indicies, $R_1$ = 0.072 and $R_2$ = 0.076 with 179 reflections for I > 3$\sigma$(I), and $R_1$ = 0.048 and $R_2$ = 0.043 with 226 reflections for I > 3$\sigma$(I), respectively. In each structure, Ca(II) ions are located on threefold axes associated with three 6-ring oxygens. $Ca^{2+}$ ions prefer to 6-ring sites and $Tl^+$ ions prefer to 8-ring sites when total number of exchanged cations per unit cell is more than 8. Ca(II) 와 Tl(I)으로 교환되고 완전히 진공 탈수된 2개의 제올라이트 A 결정 즉, $Ca_{5.6}Tl_{0.8}-A (a = 12.242(2){\AA})\;와\;Ca_{1.4}Tl_{9.2}-A (a = 12.191(1){\AA})$의 구조를 21(1)$^{\circ}C$에서 입방공간군 Pm3m을 사용하여 X-선 단결정 회절법으로 해석하였다. 이들 두 결정은 총농도를 0.05M로 한 $Ca(NO_3)_2$ 와 $$TINO_3$ 혼합용액을 사용하여 흐름법으로 이온교환하여 만들었고 탈수는 360$^{\circ}C$ 및 $2{\times}10^{-6}\;torr$에서 2일간 행하였다. $Ca_{5.6}Tl_{0.8}-A$ 구조에서는 I > 3$\sigma$(I)인 회절점 179개를 사용하여 $R_1$ = 0.072 와 $R_2$ = 0.076까지, $Ca_{1.4}Tl_{9.2}-A$구조에서는 I > 3$\sigma$(I)인 회절점 226개를 사용하여 $R_1$ = 0.048 and $R_2$ = 0.043까지 정밀화시켰다. 두 구조에서 Ca(II) 이온은 3개의 6-링 산소와 결합하면서 3회 회전축 상에 위치하였다. 단위세포당 교한된 양이온의 총수가 8개 이상이면 $Ca^{2+}$ 이온은 6-링 자리에, $Tl^+$ 이온은 8-링 자리에 우선적으로 위치한다.