• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 가을 학술발표회 논문집
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• pp.138-141
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• 2003

최근 어패럴 캐드 시스템을 지원하기 위해 3차원 레이저 스캐너로부터 획득된 데이터를 해석적 곡면으로 재구성하는 연구가 활발히 진행되고 있다. 이를 위해 역공학(reverse engineering)을 이용하여 인체를 모델링 하는 시도는 패션, 의료 둥의 분야에서 그 수요가 증가하고 있지만, 그 대상이 되는 인체가 매우 불규칙하기 때문에 기하학, 해석학적으로 접근하기가 어렵고, 시도 또한 미비한 실정이다. (중략)

• 대한조선학회논문집
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• 제43권3호
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• pp.375-383
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• 2006

This paper presents NURBS skinning for the forebody of ship. NURBS skinning is guessed as a good method to generate the faired surface of ship forebody, but it is very problematic in real ship design to generate resonable surface of ship forbody using skinning, because there are lot of problem to apply skinning and to get reasonable surface. One of main problem is data arrangement with design data. Irregular serial contour data arise so serious compatibility problem of knot vector This paper suggests a whole process using skinning successfully in generating hull form of ship forebody This process includes how to make the data set for skinning and how to execute compatibility procedure.

• 대한족부족관절학회지
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• 제15권3호
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• pp.149-152
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• 2011

Purpose: The Akin osteotomy which is a closing wedge osteotomy of the proximal phalanx widely used for the correction of hallux valgus has several methods of fixation. we tried to report the effects of the fixation using an absorbable suture material during the Akin osteotomy for the hallux valgus. Materials and Methods: This study was based on 448 cases of 346 patients who were able for follow-up more than 12 months among the patients who had an Akin osteotomy together with the surgery of hallux valgus between March of 2006 and May of 2010. Absorbable suture material had been used in all cases. Radiologically displacement and union of osteotomy site were observed after the surgery, and clinically postoperative complication such as skin irritation, pain and satisfaction were investigated. Results: Radiologically all cases had showed complete union and no case had the loss of an correction due to loss of fixation. Also, any case had no skin irritation due to a knot. Three cases had a medial cortical breakage due to a strong knot, and the initial one case among them had additionally fixed the osteotomy site for four weeks using K-wire, and the remaining two cases had fixed a suture on an articular surface without any fixation of an additional wire. If a medial cortical bone was lost by carrying out an ostectomy due to proximal protrusion of proximal phalanx, three cases could show union through the fixation of suture on an articular surface. Conclusion: This study considers that the fixation of the osteotomy site using an absorbable suture material in an Akin osteotomy was effective method and the advantage of this procedure was unnecessity of the material removal and no skin irritation.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.979-982
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• 2001

In CNC machining, demands on precision machining of free formed surface model are increasing. Most of the CAD/CAM systems provide the NURBS(Non-Uniform Rational B-Spline) interpolator. NURBS is defined with NURBS parameter by control point, weight value and knot value. This paper shows the realtime NURBS interpolation algorithms and compared with each other. One is based on the equal length of curve segments rather than equal increment of the parameter Δu. The other is to limit the interpolation error to any desired level by adjusting the feedrate considering the curvature of the shape and sampling time.

• 한국해양학회지
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• 제19권2호
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• pp.118-124
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• 1984

黃海의 海上風에 의한 重力波의 波高와 週期를 SMB法을 使用하여 計算 하였다. 그리고 黃海에서 樹勢한 北西風과 南西風이 40knots에 달할 때의 波浪活動 에 의한 海底流速과 海底剪斷應力을 線形波浪理論과 Kajiura(1968)의 暖流振動境界層分析에 의해 구하였다. 計算 缺課를 보면 韓半島의 西海沿近海域 에서 가장 큰 海波와 剪斷應力의 分布를 보이며 이로 인하여 沿近海底面이 持續的인 影響를 받고 있음이 나타났다.

• Industrial Engineering and Management Systems
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• 제9권4호
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• pp.323-338
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• 2010

In this paper, we introduce the implied volatility from Black-Scholes model and suggest a model for constructing implied volatility surfaces by using the two-dimensional cubic (bi-cubic) spline. In order to utilize a spline method, we acquire grid (knot) points. To this end, we first extract implied volatility curves weighted by trading contracts from market option data and calculate grid points from the extracted curves. At this time, we consider several conditions to avoid arbitrage opportunity. Then, we establish an implied volatility surface, making use of the two-dimensional cubic spline method with previously estimated grid points. The method is shown to satisfy several properties of the implied volatility surface (smile, skew, and flattening) as well as avoid the arbitrage opportunity caused by simple match with market data. To show the merits of our proposed method, we conduct simulations on market data of S&P500 index European options with reasonable and acceptable results.

• 한국의상디자인학회지
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• 제10권2호
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• pp.125-138
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• 2008

For physical and hand property evaluation of fabrics, the knitted fabrics from 11 types of machines knitting fancy yarns, boucle (M1), knot (M2), snarl (M3), and slub (M4), tamtam (M5), tubular (M6), fur 1 (M7), bead (M8), fur 2 (M9), fur 3 (M10), and ladder (M11) yarns, were prepared with 7-10 G plain stitch. Washing test and pilling test had also been carried out. For hand properties by objective sensibility evaluation, 17 items of sir mechanical properties using KES-FB (Kawabata Evaluation System) had been measured. Then hand values of knitted fabrics were calculated with a calculation formula, namely KN-402-KT. Finally the total hand values were obtained through KN-301-WINTER. As a result of physical properties and objective evaluation for machines knitting fancy fabrics, most of them shrank in the direction of wale and course after the washing test, in which their shrinkage rate had a maximum of 3.5%. Therefore, the washing test indicated that the shrinkage ratio of knitted fabrics had a minor change. The results of the pilling test are mostly 4-5th grade, and all of the machines knitting fancy fabrics showed good results in the pilling resistance. In hand properties and objective sensibility evaluation, twisted fancy yarns, such as boucle (M1), knot (M2), snarl (M3), and slub (M4), were superior to bonding rigidity (B) and shear rigidity (G). The surface property between course and wale differs in all samples and course direction is tougher than wale direction. FUKURAMI (fullness and softness) of all samples have high values, besides NUMERI (smoothness) of tamtam (M5) and boucle (M1), which were rather good. Most samples except fur 1 (M7) had low KOSHI (stiffness) value. The total hand value (THV) of twisted yarns was low. This study proves that manufacturers, who plan knitting yarn products and knit fashion, can apply these data to develop machines knitting yarns and knits that fit the consumers' demands.

• 한국해양학회지
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• 제6권1호
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• pp.49-55
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• 1971

1969년 10월에 완성된 남강 다목점 댐과 방수로가 준공되어 1969년에 7회, 1970년에 3회 합계 10회에 걸쳐 1,359 $10^{6}$㎥ 이상의 담수를 진주만으로 방수하였다. 방수 속도는 최고 약 3,770㎥/sec 에 이르렀으며 1회 누적 방수량은 최고 4.50 $10^{6}$㎥ 이상에 달하였다. 이 결과 방수로 하류부와 연결되는 사천만 북부에서는 5kt 이상의 빠른 유속이 해저의 토사를 이동시켜 간석지와 해저의 지형을 변동시켰다. 양식장 시설물과 패류를 매몰, 유실 시키는 원인이 되었다. 하구 현상이 일어 났으며 2중조가 관측되었다. 어구의 파손, 발장의 도괴 및 어선의 조업 불능 등으로 피해가 막심하였다. 방수후 진주만의 염분은 급격히 하강하였으며 특히 사천만 에서는 밀물때에도 5 이하의 이상저염분수가 분포하였다. 현저한 조경이 이루어졌으며 반조석 주기에 4.6 에서 30 로 약 25 이상의 염분 급변이 있었다. 이와같은 염분의 저하와 급변은 동해역의 굴, 바지락 등 패류를 폐사시키고 멸치, 문어 등을 만외로 추방하는 원인이 되었으며, 내유 어군의 접근을 방해하였다. 염분의 저하는 해수의 밀도와 삼투압 환경을 급변 시키는 원인이 되었고, 투명도가 낮은 혼탁한 물덩이는 광선의 투입을 방해하여 광합성 작용을 억제할 것이다.

• 대한관절경학회지
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• 제11권1호
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• pp.63-68
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• 2007

목적: 전방 십자 인대 손상과 동반된 외측 반월상 연골 경골 후방 부착부 완전 방사상 파열 환자에서 전외측 및 전내측 도달법을 통한 all-inside 봉합 술기를 시술하여 온 바, 이를 소개하고자 한다. 수술 술기: 관절경을 전내측 도달법으로, 봉합용 갈고리(suture hook, $Linvatec^{TM}$, Largo, Florida, USA)를 전외측 도달법으로 관절에 삽입한 상태에서 봉합용 갈고리를 틀어서 외측으로 전위된 외측 반월상 연골 후각부 파열단의 대퇴골측 면에서 경골측 면으로 수직으로 통과시킨다. 갈고리 내로 PDS No. 1 ($Ethicon^{TM}$, Somerville, NJ, USA)를 통과시킨 후 봉합용 갈고리를 빼내고 전외측 도달법 입구로 봉합사의 양끝을 뽑아낸다. MAXON 2-0 ($Syneture^{TM}$, Norwalk, Connecticut, USA)를 봉합용 갈고리를 이용하여 경골 부착부 파열단 경골측 면에서 대퇴골측 면으로 봉합사를 수직으로 통과시켜 양끝을 전외측 도달법 입구로 빼내어 두 봉합사의 경골 측 끝 중 PDS를 MAXON에 결찰하여 MAXON의 대퇴골측 끝을 전외측 도달법으로 당겨 이를 PDS로 교체한 뒤 SMC(Samsung Medical Center) knot를 이용하여 결찰한다. 결론: 본 술기를 시행하여 외측 반월상 연골 후방 부착부 파열을 해부학적으로 봉합할 수 있으며 또한 반월상 연골의 연골 장력(hoop tension)을 효과적으로 회복시켜 줄 수 있을 것으로 생각된다.

• 한국가구학회지
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• 제12권1호
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• pp.27-37
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• 2001

Automation of wood processing is strongly required to improve the productivity and quality of wood products in wood industry which is one of the most labor-intensive industries. Classification of surface defects on wood boards such as knots is one of the important steps towards a completely automated wood processing system. In this study the possibility of detection of knots by image processing technique was investigated. Algorithm for the automatic determination of threshold value was developed to enhance the flexibility of image processing system. Two different approaches, grid method and tile method, were developed to enhance the speed in extracting features from images. Grid method showed slightly higher processing speed and tile method proved much more stable in determining threshold values. Tile size of $5{\times}5$ pixels or $6{\times}6$ pixels was found to be proper to get stable results with resonable processing time.