사회 : 죽음을 싣고 가는 서울지하철 정비실태

최정한 사회평론 1992 월간 사회평론 Vol.92 No.8

婦人服 原型의 比較硏究

崔貞閑 朝鮮大學校 師範大學 1974 師大論文集 Vol.5 No.-

저밀도 내피세포 환자의 백내장 수술 후 장기 임상결과

최정한,오한진,윤경철,Jung,Han,Choi,Han,Jin,Oh,Kyung,Chul,Yoon 대한안과학회 2013 대한안과학회지 Vol.54 No.4

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Purpose: To investigate the long-term results after cataract surgery in eyes with low endothelial cell density (ECD). Methods: A retrospective medical record review was performed of 19 patients with low ECD (lower than 1000 cells/mm2) who 31 patients with a normal ECD (higher than 1600 cells/mm2) underwent cataract surgery. Clinical parameters including visual acuity, intraocular pressure (IOP), spherical equivalent refraction, anterior chamber depth, axial length and central corneal thickness (CCT) were measured and specular microscopy was performed to analyze the ECD and its morphology. The follow-up periods were 1 week, and 1, 3, 6 and 12 months postoperatively. Results: Clinical parameters except ECD and CCT had no significant difference between the 2 groups until 12 months postoperatively. The decreasing rate of ECD and increase of CCT were significantly different between the 2 groups at 1 week and 1 month postoperatively. However, no significant difference was found after 3 months postoperatively. Only 1 eye in the low ECD group with 367 cells/mm2 developed bullous keratopathy. Conclusions: In the low ECD group, a significant decrease of ECD and increase of CCT were observed at 1 month after cataract surgery. However there were no significant differences compared with the control group after 3 months postoperatively. The results suggest that cataract surgery is safe postoperatively for a long-term for a patient with low ECD.

Magnetic Resonant Wireless Power Transfer with L-Shape Arranged Resonators for Laptop Computer

최정한,강석현,정창원 한국전자파학회 2017 Journal of Electromagnetic Engineering and Science Vol.17 No.3

In this study, we designed, measured, and analyzed a rearranged L-shape magnetic resonance coupling wireless power transfer (MRWPT) system for practical applications with laptops. The typical four resonator MR-WPT (Tx part: source loop and Tx coil; Rx part: Rx coil and load loop) is difficult to apply to small-sized stationary and mobile applications, such as laptop computers, tablet-PCs, and smartphones, owing to the large volume of the Rx part and the spatial restrictions of the Tx and Rx coils. Therefore, an L-shape structure, which is the orthogonal arrangement of the Tx and Rx parts, is proposed for indoor environment applications, such as at an Lshaped wall or desk. The relatively large Tx part and Rx coil can be installed in the wall and the desk, respectively, while the load loop is embedded in the small stationary or mobile devices. The transfer efficiency (TE) of the proposed system was measured according to the transfer distance (TD) and the misaligned locations of the load loop. In addition, we measured the TE in the active/non-active state and monitor-open/closed state of the laptop computer. The overall highest TE of the L-shape MR-WPT was 61.43% at 45 cm TD, and the TE decreased to 27.9% in the active and monitor-open state of the laptop computer. The conductive ground plane has a much higher impact on the performance when compared to the impact of the active/non-active states. We verified the characteristics and practical benefits of the proposed L-shape MR-WPT compared to the typical MR-WPT for applications to L-shaped corners.

안구돌출을 주소로 진단된 신세포암의 눈물샘 전이 1예

최정한,박인기,서경훈,신재호,Jeong,Han,Choi,In,Ki,Park,Kyung,Hoon,Seo,Jae,Ho,Shin 대한안과학회 2012 대한안과학회지 Vol.53 No.12

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Purpose: To report a very rare case of lacrimal gland metastasis of renal cell carcinoma presenting with proptosis. Case Summary: A 68-year-old man visited our clinic with a 3-month history of proptosis in the right eye. Corrected visual acuity was 0.8 in the right eye and 0.9 in the left eye and 11 mm proptosis of the right eye was observed. There were no specific findings except cataracts in both eyes. Orbital computed tomography (CT) demonstrated a solid lacrimal gland mass which was 24 × 36 × 29 mm in size and showed irregular enhancement. The CT scan also showed bone destruction around the orbital lateral wall and infiltration to the lateral rectus muscle. A metastatic tumor was suspected, thus a chest CT and abdominal CT were performed. The CT scan showed a large exophytic hypervascular mass with heterogeneous enhancement. The mass size was confirmed by the abdominal CT and malignant tumors were suspected. Regarding the left renal mass, a urology surgeon performed nephrectomy and adrenalectomy and regarding the lacrimal gland mass we performed an incisional biopsy via lid crease incision. Both masses were diagnosed as renal cell carcinoma based on the pathophysiologic findings. Conclusions: Lacrimal gland metastasis of renal cell carcinoma is very rare and extensive systemic evaluation for metastatic malignancy should be performed. In the present study, the authors report of a primary tumor found by chest CT a review of the literature.

녹내장 치료 시 점안약 치료 후 안부작용에 관한 연구

최정한,박정원,박상우,Jung,Han,Choi,Jung,Won,Park,Sang,Woo,Park 대한안과학회 2013 대한안과학회지 Vol.54 No.5

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Purpose: To investigate the influence of number and type of side effects as well as treatment period after the use of anti- glaucoma eye drops in patients with glaucoma. Methods: A survey was conducted regarding the severity of ocular side effects after the use of anti-glaucoma eye drops in 528 patients with glaucoma. Side effects after using the eye drops included irritability, blurred vision, foreign body sensation, hyperemia, pinpricking sensation, itching, discomfort, pain, tearing, dry eye, and pigmentation. We analyzed the results to investigate the influence of number and type of side effects as well as treatment period. Results: The side effects after the use of anti-glaucoma eye drops were more severe and frequent in the patient groups using more than 1 eye drop (p < 0.01) and in the patients with longer treatment period (p < 0.01). Among patients using 1 eye drops, side effects developed frequently in patients using Ocucarpine<sup>®. Conclusions: In patients with glaucoma, using more than 1 anti-glaucoma eye drop or having a longer treatment period resulted in more side effects. Similaryly, patients using only 1 eye drop of Ocu-carpine<sup>® induced more side effects.

임플랜트 지지 상부구조물에서 나사조임순서와 조임방법이 풀림토크값에 미치는 영향

최정한,김창회,임영준,김명주,이석형,Choi,,Jung-Han,Kim,,Chang-Whe,Lim,,Young-Jun,Kim,,Myung-Joo,Lee,,Seok-Hyung 대한치과보철학회 2007 대한치과보철학회지 Vol.45 No.5

Statement of problem: The screw detorque value is a measure of the preload remaining in the screw just before detorquing. Purpose: This study evaluated the effect of different screw tightening sequences and tightening methods on detorque values for a well-fitting implant superstructure. Material and method: An implant superstructure that connected directly to four implants (Astra Tech) was fabricated on a fully edentulous mandibular acrylic resin model. Six well-fitting dental stone casts were made with a pickup impression of the superstructure from the acrylic resin model. To evaluate the effect of three screw tightening sequences (1-2-3-4, 2-4-3-1, and 2-3-1-4) and two tightening methods (2-step and 1-step) on the stability of screw joint, the detorque values for a well-fitting implant superstructure were measured twice after screw tightening using 20 Ncm. Detorque values were analyzed using multi-way analysis of variance and two-way analysis of variance at a .05 level of significance. Results: 1. The mean detorque values for three screw tightening sequences were 12.3 Ncm, 12.6 Ncm, and 12.0 Ncm, respectively. 2. The mean detorque values for two screw tightening methods were 12.0 Ncm, and 12.2 Ncm, respectively. 3. The mean of mimimum detorque values for three screw tightening sequences and for two tightening methods were 10.6 Ncm, 11.1 Ncm, 10.5 Ncm, and 9.8 Ncm, respectively. 4. No statistically significant differences among the variables of screw tightening sequence and tightening method were found (p>.05) for detorque values and for mimimum detorque values. Conclusion: Within the limitations of this study, the screw tightening sequence and tightening method did not have a significant effect on the detorque values for a well-fitting implant superstructure.

내부연결 임플란트 상부구조물에서 나사조임술식이 풀림토크값에 미치는 영향

최정한,Choi,,Jung-Han 대한치과보철학회 2010 대한치과보철학회지 Vol.48 No.4

연구 목적: 본 연구는 잘 맞는 임플란트 상부구조물에서 서로 다른 나사조임순서와 조임방법이 나사의 풀림토크값에 미치는 영향을 평가하였다. 연구 재료 및 방법: 서로 수동적 적합 관계를 갖는 완전 무치악 하악 주모형과 네 개의 평행한 임플란트 (Astra Tech)에 직접 연결되는 금속구조물을 제작하였다. 금속구조물과 잘 맞는 실험모형을 위해 주모형에서 연결인상법을 이용하여 여섯 개의 경석고 모형을 얻었다. 20 Ncm로 조인 후 나사의 풀림토크값을 두 번 측정하였다. 세 가지 나사조임순서 (1-2-3-4, 2-4-3-1, 그리고 2-3-1-4)와 두 가지 나사조임방법 (two-step과 one-step)에 대한 나사의 풀림토크값과 최소풀림토크값을 유의수준 .05에서 각각 다원분산분석법 (multi-way ANOVA)과 이원분산분석법 (two-way ANOVA)을 이용하여 통계분석 하였다. 결과: 나사조임순서에 대한 나사의 평균 풀림토크값은 12.8 Ncm (2-4-3-1)에서 13.1 Ncm (2-3-1-4)의 값을 보였고, 나사조임방법에 대한 값은 13.1 Ncm (two-step)와 11.8 Ncm (one-step)였다. 나사조임순서에 대한 나사의 평균 최소풀림토크값은 11.1 Ncm (1-2-3-4)와 11.2 Ncm (2-4-3-1과 2-3-1-4)였고, 나사조임방법에 대한 값은 11.2 Ncm (two-step)와 9.9 Ncm (one-step)였다. 나사의 풀림토크값과 최소풀림토크값은 세 가지 나사조임순서 간에 통계학적으로 유의성 있는 차이가 없었다. 그러나 두 가지 나사조임방법 간에는 두 값 모두 통계학적으로 유의성 있는 차이가 있었다. 나사를 두 단계로 나누어 조이는 방법이 한 번에 조이는 방법보다 더 큰 풀림토크값 (P = .0003)과 더 큰 최소풀림토크 값 (P = .0035)을 보였다. 결론: 본 연구와 같은 조건하에서, 연결인상법으로 얻은 잘 맞는 임플란트 상부구조물에 있어서 나사조임순서는 나사의 풀림토크값에 영향을 미치는 중요한 요소는 아니었다. 그러나 나사를 두 단계로 나누어 조이는 방법은 한 번에 조이는 방법보다 더 큰 풀림토크값을 보였다. Purpose: This study evaluated the effect of different screw tightening sequences and methods on detorque values in a well-fitting implant superstructure. Materials and methods: A fully edentulous mandibular master model and a metal framework directly connected to four parallel implants (Astra Tech) with a passive fit to each other were fabricated. Six stone casts were made with a splinted impression technique to represent a 'well-fitting' situation with the metal framework. Detorque values were measured twice after screw tightening using 20 Ncm. Detorque values and minimum detorque values for three screw tightening sequences (1-2-3-4, 2-4-3-1, and 2-3-1-4) and for two tightening methods (two-step and one-step) were analyzed using multi-way analysis of variance and two-way analysis of variance, respectively, at a .05 level of significance. Results: The mean detorque values for screw tightening sequences ranged from 12.8 Ncm (2-4-3-1) to 13.1 Ncm (2-3-1-4), and for screw tightening methods were 13.1 Ncm (two-step) and 11.8 Ncm (one-step). The mean of mimimum detorque values for screw tightening sequences were 11.1 Ncm (1-2-3-4) and 11.2 Ncm (2-4-3-1 and 2-3-1-4), and for screw tightening methods were 11.2 Ncm (two-step) and 9.9 Ncm (one-step). No statistically significant differences among three screw tightening sequences were found for detorque values and for mimimum detorque values. But, statistically significant differences between two screw tightening methods were found for two values. Two-step screw tightening method showed higher detorque value (P = .0003) and higher minimum detorque value (P = .0035) than one-step method. Conclusion: Within the limitations of this study, the screw tightening sequence was not a critical factor for the detorque values in a well-fitting implant superstructure by the splinted impression technique. But, two-step screw tightening method showed greater detorque values than one-step method.

임상적 방법을 이용한 내부연결 임플랜트에서 고정체수준 인상법의 정확도 평가

최정한,Choi,Jung-Han 대한치과보철학회 2006 대한치과보철학회지 Vol.44 No.4

Statement of problem : Accurate impression is essential to success of implant prostheses. But there have been few studies about the accuracy of fixture-level impression technique in internal connection implant system. Purpose: This study evaluated the accuracy of splinted fixture-level impression technique using clinical methods and the effect of internal hex on fit of superstructure in internal connection implant system (Astra Tech). Material and method : Two metal master frameworks made from two abutments (Cast-to Abutment ST) each for parallel and divergent conditions and a corresponding. passively fitting, dental stone master cast with four future replicas (Fixture Replica ST) were fabricated. Ten dental stone casts were made with vinyl polysiloxane impressions from the master cast by acrylic resin splinted fixture-level impression technique. To evaluate the accuracy of impression technique, the fit of master frameworks for test models was evaluated using screw resistance test (SRT) and one-screw test. The results of SRT were recorded as SRT values from grade 1 to grade 5 by 1/4 turn. And to evaluate the effect of hex on fit of superstructure, the same tests were performed after removing hexes of master frameworks. Results: 1. There was only one case (2.5%) showing SRT value of test model below ade 2 in total before and after removing hexes of master frameworks. And, by removing hexes. SRT values decreased in only one test model (5%) and did not change in 17 test models (85%). 2. SRT values of the 1$^{st}$ screws were grade 2 in 80% of cases before, and grade 1 in 80% of cases after removing hexes. And, by removing hexes, SRT values decreased in 72.5% of cases. 3. SRT values of the 2$^{nd}$ screws were grade 3 in 85% of cases before, and grade 3 in 95% of cases after removing hexes. And, by removing hexes, SRT values did not change in 85% of cases. 4. There were only 2 cases regarded as acceptable fit by one-screw test, and SRT values of 2$^{nd}$ screws of both cases were grade 2. Conclusion. Within the limitations of this study, future-level impression of internal connection implant system is considered to obtain inaccurate working cast, even using acrylic resin splinted impression technique. And, it is considered to be unable improve the fit to remove the hexes of implant restoration.

이식편대숙주질환과 관련된 건성안 환자에서 사이클로스포린A과 제대혈청 병합치료의 효과

최정한,오한진,윤경철,Jung,Han,Choi,Han,Jin,Oh,Kyung,Chul,Yoon 대한안과학회 2013 대한안과학회지 Vol.54 No.4

'스콜라' 이용 시 소속기관이 구독 중이 아닌 경우, 오후 4시부터 익일 오전 7시까지 원문보기가 가능합니다.

Purpose: To investigate the efficacy of combined treatment with 0.05% cyclosporine A and 20% umbilical cord serum eye drops for severe dry eye associated with graft-versus-host disease (GVHD). Methods: Eighteen patients with severe dry eye associated with GVHD were treated with 0.05% cyclosporine A and 20% umbilical cord serum eye drops (group 1, n = 16), 0.05% cyclosporine A eye drops (group 2, n = 10) or artificial tears only (group 3, n = 10). Tear film break up time (BUT), Schirmer test, tear clearance rate (TCR), and keratoepithelio pathy score were measured before and 1, 3 and 6 months after treatment. Results: In group 1, significant improvement was observed in tear film BUT (from 3.25 ± 1.18 s to 6.63 ± 0.96 s, p < 0.01), TCR (from 2.38 ± 0.72 to 3.13 ± 0.72, p < 0.01) and keratoepithelio pathy score (from 6.31 ± 2.15 to 0.88 ± 0.89, p < 0.01) 6 months after treatment. Compared with group 2 and group 3, group 1 showed significant improvement in BUT (3 and 6 months after treatment) and keratoepitheliopathy score (1, 3 and 6 months after treatment). Conclusions: Combined treatment with 0.05% cyclosporine A and 20% umbilical cord serum eye drops is effective for severe dry eye associated with GVHD.