백내장 수술 후 각막 지각의 변화와 각막신경 회복의 비교

김용민,김선웅,김태임,김응권,서경률,Yong Min Kim,Sun Woong Kim,Tae Im Kim,Eung Kwon Kim,Kyung Ryul Seo 대한안과학회 2007 대한안과학회지 Vol.48 No.1

Purpose: To compare corneal sensitivity and recovery of corneal innervations after a temporal clear corneal incision in cataract surgery. Methods: We measured changes to corneal sensitivity using Cochet-Bonnet esthesiometer in 25 eyes of 20 patients and analyzed corneal nerve density with confocal microscopy in 20 eyes of 20 patients who had undergone cataract surgery. The parameters were measured before, and at 1 week, 1 month, and 3 months after cataract surgery. Results: The mean preoperative corneal sensitivity was 56.40±3.39 mm at the temporal corneal incision site, and there was a significantly decreased sensitivity of 29.80±2.69 mm and 42.40±4.36 mm postoperatively at 1 week and 1 month, respectively. Nonetheless, by three months, corneal sensitivity had returned to 56.00±2.89 mm and was not significantly different from measurements prior to the cataract surgery. The mean preoperative subbasal nerve density was 5296±1642 ?m/mm2. After cataract surgery, the subbasal nerve density was significantly reduced to 4113±1421, 3555±1448, 4198±1239 ?m/mm2 at 1 week, 1 month, and 3 months, respectively. Conclusions: Corneal sensitivity after cataract surgery returned to near preoperative levels within 3 months before complete restoration of normal corneal innervations. Therefore, regeneration of subbasal nerve fibers (, as determined by confocal microscopy,) requires more time than the return of corneal sensation after cataract surgery.

만성 발목 관절 외측 불안정성의 진단에서 스트레스 방사선검사의 유용성

김용민,조병기,김동수,최의성,손현철,박경진,김동환,Kim, Yong-Min,Cho, Byung-Ki,Kim, Dong-Soo,Choi, Eui-Sung,Shon, Hyun-Chul,Park, Kyoung-Jin,Kim, Dong-Hwan 대한정형외과스포츠의학회 2011 대한정형외과스포츠의학회지 Vol.10 No.1

목적: 만성 발목 관절 외측 불안정성 환자에 대한 기계적 불안정성의 평가에서 스트레스 방사선검사의 진단적 유용성을 알아보고자 하였다. 대상 및 방법: 본원에서 변형 Brostrom 술식을 시행받은 환자들 중 수술 소견상 외측 측부인대(전 거비 인대)의 완전 파열이 확인되었던 42예를 대상으로 하였다. 대조군으로는 발목 관절 손상의 과거력이 없고 이학적 검사상 불안정성 소견을 보이지 않는 정상 한국인 성인 총 60명(120예)을 모집하였다. Telos 기구를 이용한 전방 전위 및 내반 스트레스 검사를 시행한 뒤, 거골 경사각과 거골 전방전위 정도를 계측하였다. 대조군에서 얻어진 정상범위를 기준으로 스트레스 방사선검사의 민감도, 특이도, 양성 예측도, 음성 예측도를 분석하였다. 결과: 스트레스 방사선검사 상 정상 한국인 성인에서의 거골 경사각은 평균 $4.2{\pm}2.1$도, 거골 전방전위는 평균 $3.9{\pm}1.9$ mm로 계측되었다. 95% 신뢰한계 분석을 이용한 정상 범위의 설정시 거골 경사각의 정상 범위는 8.3도 이하, 거골 전방전위는 7.6 mm 이하로 분석되었다. 이 수치를 기준값으로 하는 경우 발목 관절 스트레스 방사선검사 상 거골 경사각의 민감도는 57%, 특이도는 97%, 양성 예측도는 89%, 음성 예측도는 86% 였고, 거골 전방전위의 민감도는 69%, 특이도는 97%, 양성 예측도는 91%, 음성 예측도는 90% 였다. 결론: 만성 발목 관절 외측 불안정성 환자에 대한 기계적 불안정성의 평가에서 스트레스 방사선검사는 비교적 우수한 특이도 및 양성, 음성 예측도를 보였으나 민감도는 낮아, 유용하지만 정확성은 떨어지는 검사법인 것으로 분석되었다. 기계적 불안정성이 발목 관절 스트레스 방사선검사 상 실제보다 덜 반영된다고 생각되며, 스트레스 방사선검사 소견만으로 발목 관절 외측 불안정성을 배제해서는 안 될 것으로 생각한다. Purpose: This study was performed to evaluate the diagnostic usefulness of ankle stress radiograph for evaluation of chronic lateral ankle instability. Materials and Methods: Among patients undergoing the modified-Brostrom procedure, 42 cases with complete rupture of the anterior talofibular ligament were enrolled in this study. Sixty Korean adults (120 cases) were recruited as the control group. Radiologic measurement of talar tilt and anterior talar translation was performed through stress radiographs using Telos device. We obtained the normal range of Korean adults, and used as a standard value for judgment of mechanical instability. We analyzed the sensitivity, specificity, positive and negative prediction value of ankle stress radiograph. Results: On ankle stress radiograph, normal range of talar tilt angle and anterior talar translation was below $8.3^{\circ}$, below 7.6mm. Talar tilt angle on varus stress radiograph showed 57% of sensitivity, 97% of specificity, 89% of positive and 86% of negative prediction value. Anterior talar translation on anterior drawer stress radiograph showed 69% of sensitivity, 97% of specificity, 91% of positive and 90% of negative prediction value. Conclusion: Ankle stress radiograph had a good specificity, positive and negative prediction value for the evaluation of mechanical instability. However it underestimated the mechanical instability of ankle joint. It must be remembered that normal stress radiograph does not exclude ankle instability.

순서기반 비정상행위 탐지 센서의 임계치 결정 방법

김용민,김민수,김홍근,노봉남,Kim, Yong-Min,Kim, Min-Su,Kim, Hong-Geun,No, Bong-Nam 한국정보처리학회 2001 정보처리학회논문지 C : 정보통신,정보보안 Vol.8 No.5

본 논문은 SOM과 HMM을 이용하여 시스템 호출 수준에서 순서기반의 비정상행위 탐지 센서를 구현하였다. 그리고, 시스템 호출에서 중요한 정보가 무엇이고 임계값은 어떻게 설정해야하는 지를 분석하였다. 본 논문에서 사용한 SOM의 새로운 필터링 규칙과 축약 규칙은 HMM의 입력 크기를 줄일 수 있었다. 이러한 축약은 HMM기반 비정상행위 탐지의 실시간 처리능력을 보장해 준다. 또한, 비정상행위 수라는 개념을 도입하여 HMM의 탐지결과에 대한 민감성을 둔화시켜서, 사용자가 탐지결과를 쉽게 이해하고 false-positive를 줄이는 효과가 있었다. 그리고, 능동적으로 threshold 값을 조정하여 시스템 상황에 따라 탐지센서가 적응할 수 있도록 하였다. In this paper, we implement sequence-based anomaly detection sensor using SOM and HMM, and analyze what is important information in system call and how a threshold is decided. The new filtering and reduction rules of SOM reduces the input size of HMM. This gives real-time processing to HMM-based anomaly detection sensor. Also, we introduced an anomaly count into the sensor. Due to lessened sensibility, a user easily understand easily the detection information and false-positive was decreased. And the active coordination of the threshold value makes the detection sensor adapt according to the system condition.

Anti-Inflammatory Effects of Tongbi-san(通痺散) Extract on RAW264.7 Macrophages

김용민,김희택,김이화,Kim, Yong-Min,Kim, Hee-Taek,Kim, Ee-Hwa The Society of Korean Medicine Ophthalmology 2016 한방안이비인후피부과학회지 Vol.29 No.4

Objectives : This study is to investigate the anti-inflammatory and anti-oxidant effects of Tongbi-san extract (TS) on RAW264.7 macrophages using by cell cytotoxicity, Nitric Oxide (NO) and Prostaglandin $E_2$ ($PGE_2$) production and 1,1-diphenyl-2-picryl ghdrazyl (DPPH) free radical scavenging capability. Methods : Cell cytotoxicity was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The production of NO was measured by Griess assay. The production of $PGE_2$ was measured by immunoassay. And the anti-oxidant activity was measured by the DPPH method. Results : TS did not increased significantly compared to the TS untreated group in the cell cytotoxicity. TS inhibited NO and $PGE_2$ production in lipopolysaccharide-stimulated RAW 264.7 cells. TS had the DPPH free radical scavenging capability. Conclusion : The anti-inflammtory and anti-oxidant effects of TS may be use for a treatment of anti-inflammatory diseases.

습윤상태를 고려한 불포화 토사사면의 불안정성 해석

김용민,김재홍,Kim, Yong Min,Kim, Jaehong 대한토목학회 2013 대한토목학회논문집 Vol.33 No.4

본 연구에서는 불포화 사면에서 선행강우의 영향을 고려하고자 지반의 초기 포화도를 3가지(36, 51, 77%)로 설정하여 수리학적-역학적 동시 유한요소해석(monolithically coupled finite element analysis)을 수행하였다. 선행강우에 의한 불포화 사면의 불안정성은 사면 내 모관흡수력 분포와 사면표층의 변위를 통하여 확인할 수 있다. 또한 Drucker-Prager model의 항복경계기준(trial failure criterion)을 적용하여 강우 침투에 의한 불포화 사면의 탄성 및 소성거동을 파악하였다. 그 결과, 선행강우에 의한 지반의 초기 포화도가 클수록 강우에 의한 변위가 크게 발생하며 모관흡수력 또한 감소한다. 특히, 모관흡수력은 지반이 건조할수록 빠르게 감소하며, 초기에 동일한 모관흡수력을 갖는 사면표층에서 포화도가 작은 지반일수록 더 빠른 모관흡수력 감소를 보였다. 풍화토의 탄성과 소성거동을 구분하기 위해 사용된 Drucker-Prager model을 통해 사면 파괴가 시작되는 항복경계지점을 확인 할 수 있었다. The monolithically coupled finite element analysis for a deformable unsaturated soil slope is performed to investigate the effect of antecedent rainfall which is assumed by initial conditions varying degree of saturation (36, 51, 77%) in finite element analysis. The distributions of matric suction and deformation on slope surface obtained from numerical simulation show the instability of antecedent rainfall-induced unsaturated soil slope. Moreover, the numerical analysis using Drucker-Prager model can be checked if a soil slope has reached failure (trial failure criterion $f^{tr}$ >0, plastic behavior) or not (trial failure criterion $f^{tr}$ < 0, elastic behavior). It is found that displacement of slope surface layer increases and the matric suction on soil slope decreases with an increase of initial degree of saturation by antecedent rainfall. Especially, the matric suction of the soil slope in dry condition (S=36%) rapidly decreases rather than that in wet condition (S=51%) at the same rainfall duration. The results of the trial failure criterion ($f^{tr}$ > 0) show slope instability in the toe region and surface of the slopes.

견관절 전방 재발성 탈구 환자에서 발생한 이중 Hill-Sachs 병변 - 증례 보고 -

김용민,박경진,김동수,최의성,손현철,조병기,홍경호,Kim, Yong-Min,Park, Kyoung-Jin,Kim, Dong-Soo,Choi, Eui-Sung,Shon, Hyun-Chul,Cho, Byung-Ki,Hong, Kyung-Ho 대한관절경학회 2011 대한관절경학회지 Vol.15 No.2

Hill-Sachs 병변은 견관절 탈구 환자에서 가장 흔히 보이는 병변으로 상완골두의 후외방 골결손으로 지칭된다. 처음 탈구되는 환자에서도 관찰될 수 있으며, 탈구가 진행될 될수록 진행하여 탈구의 수와 Hill-Sachs 병변의 관찰정도는 비례관계가 있는 것으로 알려져 있다. Hill-Sachs 병변의 위치와 유무는 견관절 불안정성에 중요한 의미를 띄는 것으로 이해되고 있다. 저자들은 재발성 전방 견관절 탈구 환자에서 동반된 이중 Hill-Sachs 병변1례를 경험하였기에 문헌 고찰과 함께 보고하는 바이다. Hill-Sachs lesion is the most common lesion in shoulder dislocation patient and it represented by postero-lateral bony defect of humerus. The lesion could be found in patients who dislocate shoulder joint first time, and it is reported that Hill-Sachs lesion proportionally increases as dislocation does. The location and presence of Hill-Sachs lesion play significant roles in shoulder instability. Authors experienced a double Hill-Sachs lesion in a recurrent anterior shoulder dislocation patient, and thereby report the case with a review of the literature.

당뇨황반부종의 치료에서 유리체 절제술의 효과와 유리체강 내 트리암시놀론 주입술과의 비교

김용민,김성수,이성철,권오웅,고형준,Yong Min Kim,Sung Soo Kim,Sung Chul Lee,Oh Woong Kwon,Hyung Jun Koh 대한안과학회 2006 대한안과학회지 Vol.47 No.7

Purpose: The purpose of this study is to evaluate the benefit of pars plana vitrectomy (PPV) and removal of the internal limiting membrane (ILM) in diabetic macular edema, and to compare the effects of PPV and removal of ILM with intravitreal triamcinolone acetonide injection. Methods: Fifteen eyes of 14 patients on whom PPV and removal of the ILM (group A) were performed and 14 eyes of 14 patients who received single intravitreal triamcinolone acetonide injection (group B) for diabetic macular edema over six months were included in this study. The main outcome measures were macular thickness, as measured by optical coherence tomography and visual acuity at 1, 3, and 6 months postoperatively. Results: The mean preoperative visual acuity was 0.06±0.05 and macular thickness 516.01±120.29 ?m in group A. At 1 month postoperatively, this group showed no significant improvement of visual acuity. However, there was significant improvement at 3 and 6 months postoperatively. Macular thickness also decreased significantly at 1, 3, and 6 months postoperatively. In group B, the mean preoperative visual acuity was 0.10±0.08 and macular thickness was 548.82±116.44 ?m. At 1 and 3 months postoperatively, significant improvement of visual acuity was noted in this group. However, there was no significant difference at 6 months postoperatively. Macular thickness also decreased significantly at 1, 3, and 6 month postoperatively. Between two groups, visual acuity and macular thickness improved in Group B at 1 month postoperatively but at 6 months, visual acuity improved in Group A and there was no significant difference of macular thickness between the two groups. Conclusions: PPV and removal of the ILM are good therapeutic options for diabetic macular edema to improve visual acuity and macular thickness. These also offer more long term efficacy than intravitreal tiamcinolone acetonide injection.

기업이 바라는 공학교육 내용 - 기업 연구소의 입장에서 -

김용민,Kim Yong-Min 한국공학교육학회 1997 Ingenium(人材니움) Vol.4 No.4

전위성 관절내 종골 골절에서 최소 침습적 족근동 도달법 및 압박나사 내고정술을 이용한 수술적 치료

김용민,조병기,손현철,박지강,정호승,Kim, Yong-Min,Cho, Byung-Ki,Shon, Hyun-Chul,Park, Ji-Kang,Jeong, Ho-Seung 대한족부족관절학회 2012 대한족부족관절학회지 Vol.16 No.4

Purpose: This study was performed to evaluate the clinical outcomes of operative treatment using mini-open sinus tarsi approach for displaced intraarticular calcaneal fractures. Materials and Methods: We studied 18 cases (16 patients) of intraarticular calcaneal fractures who were treated with sinus tarsi approach by same surgeon. The mean age of patients was 44.8 years, and mean follow-up period was 17.2 months. The measurement of B$\ddot{o}$hler angle, Gissane angle, the degree of articular surface depression, and the period to union were performed through preoperative and postoperative radiographs. The clinical evaluation was performed according to hindfoot score of the American Orthopaedic Foot and Ankle Society (AOFAS) and scale of the Creighton-Nebraska health foundation (CNHF). Results: B$\ddot{o}$hler angle and Gissane angle had improved significantly from preoperative average $9.8^{\circ}$, $117.6^{\circ}$to average $22.4^{\circ}$, $113.4^{\circ}$ immediate postoperatively, and had maintained to average $21.8^{\circ}$and $114.2^{\circ}$ at the last follow-up. The degree of articular surface depression had improved significantly from preoperative average 5.2 mm to 1.2 mm at the last follow-up. All cases achieved bone union, and the period to union was average 10.5 weeks. AOFAS score was average 86.2 points at the last follow-up. There were 7 excellent, 9 good, and 2 fair results according to the CNHF scale. Therefore, 16 cases (88.8%) achieved satisfactory results. Conclusion: The minimally invasive sinus tarsi approach using headless compression screw seems to be an effective surgical method for displaced intraarticular calcaneal fractures, because of the possibility of accurate restoration of articular surface and the low risk of postoperative soft tissue complications.

JPEG 인코더를 위한 고성능 병렬 프로세서 하드웨어 설계 및 검증

김용민,김종면,Kim, Yong-Min,Kim, Jong-Myon 대한임베디드공학회 2011 대한임베디드공학회논문지 Vol.6 No.2

As the use of mobile multimedia devices is increasing in the recent year, the needs for high-performance multimedia processors are increasing. In this regard, we propose a SIMD (Single Instruction Multiple Data) based parallel processor that supports high-performance multimedia applications with low energy consumption. The proposed parallel processor consists of 16 processing elements(PEs) and operates on a 3-stage pipelining. Experimental results for the JPEG encoding algorithm indicate that the proposed parallel processor outperforms conventional parallel processors in terms of performance and energy efficiency. In addition, the proposed parallel processor architecture was developed and verified with verilog HDL and a FPGA prototype system.