• 한국생산제조학회지
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• 제19권6호
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• pp.746-752
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• 2010

Rib structure has been used to bed and column of machine tool to heighten weight stiffness ratio, cost performance and weight saving. In this paper the bed rib structure was estimated with thermal characteristics. Using superposition principle, machine tool designer can describe every complicated heat generation in the machine tool thermal source. As thermal characteristics, thermal deformation of guide rail and column and Maximum-minimum temperature variation were selected. The size, configuration and direction against the thermal loading surface operated to the thermal characteristics. The DB chart was made following rib structure estimating thermal characteristics. With superposition principle and DB chart, machine tool designer can prognosticate the thermal characteristics without FEM analysis to every bed rib structure.

• 한국정밀공학회지
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• 제28권8호
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• pp.894-903
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• 2011

In this paper, the capability index is introduced in order to improve the reliability of new concept machine tools and the method to improve the machine accuracy from the analysis of cutting process, statistical methodology and influence factors are proposed. In addition, the rib structure of bed and column in machine tools is analyzed by using the thermal impact method in order to analogize the rib pattern which has the small thermal deformation under thermal boundary condition. In the analysis of column rib structure, thermal boundary condition is separated to heat conduction and heat transfer to appropriate real boundary condition. Finally, performance chart of bed and column rib structure is provided for designer to estimate each rib pattern and select rib structure appropriating to thermal condition.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.851-856
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• 2005

The precision fabrication of aspherical lenses is increasingly required for the latest applications of compact and high resolution video-recording or camera systems. Micro-optical components, including micro-spherical or aspherical lenses and reflecting mirrors, are generally required to be manufactured with high shape accuracy, extremely low surface roughness and no surface damage. To meet the needs of the precision fabrication system, a bed which supports the micro aspherical lens fabrication machines stably and safely is required. In this study, the thickness of the ribs of the bed is optimized using the CAD integrated optimal design system, a virtual DS program.

• 복식문화연구
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• 제18권1호
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• pp.109-117
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• 2010

편성물은 여러 가지 형태의 편성 조직을 얻기 위해서 횡편기나 환편기 등의 다양한 니트 편기를 이용하여 다양한 형태의 니트 편환과 조건에 의해서 편성을 하게 된다. 입체적인 형태의 니트 편지는 각기 다른 니트 편환 조직의 병용, 다양한 편사의 이용, 또는 여러 가지 가공공정 등을 거쳐서 얻을 수 있다. 본 연구는 컴퓨터화된 자동 횡편기를 이용하여 편성에 있어서 기본이 되는 조직인 리브편과 펄편의 편성조직을 효과적으로 혼합 편성하여 새로운 형태의 입체 니트구조를 갖는 편지를 개발하는데 그 목적이 있다. 이러한 입체 니트조직을 바탕으로 하여 몇 가지 다른 형태의 입체구조를 갖는 편성물을 개발하고, 새로운 형태의 니트 패션 의복을 제작한다. 또한 리브편과 펄편에 의한 입체 편성조직의 원리와 특성 등에 대하여 논한다.

• Journal of Chest Surgery
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• 제29권11호
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• pp.1263-1266
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• 1996

단국대학교병원 흉부외과에서는 좌전하행지 기시부부터 95% 이상 협착을 보이는 단일혈관질환 1례에서 체외순환없이 제한적 전흉부 개흉으로 좌측내유동맥을 박리하여 박동심장하에서 관상동맥우회술을 성공적으로 시행하였기에 보고하는 바이다.

• Composites Research
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• 제19권2호
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• pp.13-19
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• 2006

본 논문에서는 미세 방전가공(Electrical Discharge Machining; EDM) 기계를 위한 샌드위치 구조를 설계하기 위해 복합재료의 적층 순서, 두께, 그리고 리브의 형상 등을 고려한 파라메트릭 연구를 수행하였다. 샌드위치 구조는 면재인 섬유강화 복합재료와 심재인 레진 콘크리트 및 고분자 포움으로 이루어졌다. 컬럼은 정적 굽힘강성과 비굽힘강성을 높이기 위해 십자 리브를 가진 형상으로 설계하였으며, 적층 순서와 두께를 조절하였다. 베드의 경우 양방향의 강성을 동시에 향상시키기 위해 적층 순서와 리브 형상을 조절하였다. 최적의 고강성을 얻기 위하여 리브의 두께와 면재의 두께 등 설계 파라메터의 최적치를 제안하였다. 각 설계 파라메터의 변화에 따른 구조의 정적, 동적 강성의 변화를 확인하기 위해 유한요소해석을 수행하였으며, 진동 실험을 통하여 각 요소의 고유진동수와 감쇠비를 측정하여 비교하였다. 이러한 결과로부터 고정밀 미세 방전가공 기계 구조를 위한 최적의 형상조건을 제안하였다.

• Journal of Species Research
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• 제5권3호
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• pp.503-513
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• 2016

Two unrecorded marine nematode species, belonging to genus Paracanthonchus Micoletzky, 1924, are described on the basis of the specimens collected from rocky intertidal seagrass bed on the eastern coast of Korea. Paracanthonchus macrodon (Ditlevsen, 1918) is characterized by presence of cuticular differentiation, strongly dilated gubernaculum with numerous cusps, three post-cloacal setae, and arrangement of six (4+2) precloacal supplement. Paracanthonchus kamui Kito, 1981 is distinguished from other species of the genus by having the 4.25 turns amphideal fovea, six tubular supplement, rib-shaped gubernaculums with proximally hook-shaped and distally broaden. In this study, we provide taxonomic description and illustration of two unrecorded species of the genus Paracanthonchus by differential interference contrast microscopy. This is the first report on the species of the genus Paracanthonchus from Korea.

• Journal of Chest Surgery
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• 제9권2호
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• pp.293-297
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• 1976

One mid-esophageal carcinoma underwent esophagogastrectomy using an exclusive right thoracic approach entailing mobilization of the stomach through the esophageal hiatus. 62 year old male farmer was admitted with chief complaints of dysphagia and weight loss of 5 Kg. for 6 months, and regurgitation after soft meal for one week prior to this admission. Preoperative esophagogram revealed stricture with fungating mass at the level of the carina, which was diagnosed as squamous cell carcinoma at the time of esophagoscopic biopsy about 33 cm from incisor. Bronchoscopy revealed no invasive lesion or carinal fixation, and laboratory examinations were excellent for operative intervention. An exclusive right thoracic approach through right 5th rib bed was made for radical esophagectomy, mobilization of the stomach through the esophageal hiatus and primary esophagectomy. Postoperative recovery was uneventful except increased bronchial secretion due to senile emphysema, and follow up for 5 months after esophagectomy revealed good functioning esophagus with mild epigastric fullness after meal. Exclusive right thoracic approach for radical esophagectomy seems to be the procedure of choice in selected cases.

• Journal of Chest Surgery
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• 제27권6호
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• pp.489-493
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• 1994

Our patient was a 2.3 kg, male of 33 weeks gestation and spontaneous vaginal delivery. Copious salivary secretion, mild aspiration pneumonia episode due to tracheoesophageal fistula and intermittent cyanotic appearance due to hypoxia were noted shortly after birth. Head up position, frequent upper pouch suction, and adequate fluid and antibiotic therapy were done in incubator. Combined Chest and abdominal film was revealed gas in the stomach and an haziness in right chest with mediastinal shift to the right side. Esophagogram revealed markedly dilated proximal esophagus as blind pouch, and Two dimensional echocardiography showed the Ventricular Septal Defect. The conclusion was congenital esophageal atresia with tracheoesophageal fistula, Vogt-Gross type C, Waterston Risk Category B. Surgical correction with Beardmore anastomosis was performed extrapleurally through 3rd rib bed after the cannulation of umbilical vein and preliminary gastrostomy. The fistula was closed by triple ligation and the upper pouch was then brought down to the presenting surface of the lower esophageal segment that incised, and end to side anastomosis was underwent using interrupt suture placed through the full thickness of both upper pouch and lower esophageal segment. The postoperative patient was well tolerated and recovered uneventfully, permitted feeding on 7th postoperative day after esophagogram.

• The Journal of Advanced Prosthodontics
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• 제2권4호
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• pp.148-153
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• 2010

PURPOSE. The aim of this study was to investigate a comparison of implant bone bed preparation with Er,Cr:YSGG laser and conventional drills on the relationship between implant stability quotient (ISQ) values and implant insertion variables. MATERIALS AND METHODS. Forty implants were inserted into two different types of pig rib bone. One group was prepared with conventional drills and a total of 20 implants were inserted into type I and type II bone. The other group was prepared with a Er,Cr:YSGG laser and a total of 20 implants were inserted into type I and type II bone. ISQ, maximum insertion torque, angular momentum, and insertion torque energy values were measured. RESULTS. The mean values for variables were significantly higher in type I bone than in type II bone (P < .01). In type I bone, the ISQ values in the drill group were significantly higher than in the laser group (P < .05). In type II bone, the ISQ values in the laser group were significantly higher than in the drill group (P < .01). In both type I and type II bone, the maximum insertion torque, total energy, and total angular momentum values between the drill and laser groups did not differ significantly (P ${\geq}$ .05). The ISQ values were correlated with maximum insertion torque (P < .01, r = .731), total energy (P < .01, r = .696), and angular momentum (P < .01, r = .696). CONCLUSION. Within the limitations of this study, the effects of bone bed preparation with Er,Cr:YSGG laser on the relationship between implant stability quotient (ISQ) values and implant insertion variables were comparable to those of drilling.