SESSION 11 . 컴퓨터 활용 : 무인 자동차 개발 연구

최진욱,한민홍 ( Jin Wook Choi,Min Hong Han ) 대한산업공학회 1993 대한산업공학회 추계학술대회논문집 Vol.1993 No.-

임플랜트 지대주 나사의 텅스텐 카바이드/탄소 코팅이 전하중에 미치는 영향에 관한 연구

최진욱,정창모,전영찬,임장섭,정희찬,엄태관,Choi Jin-Uk,Jeong Chang-Mo,Jeon Young-Chan,Lim Jang-Seop,Jeong Hee-Chan,Eom Tae-Gwan 대한치과보철학회 2006 대한치과보철학회지 Vol.44 No.2

Statement of problem: In order to increase preload with reducing the friction coefficient, abutment screws coated with pure gold and Teflon as dry lubricant coatings have been introduced. But the reported data indicate that if screw repeated tightening and loosening cycle, an efficiency of increasing preload was decreased by screw surface wearing off. Purpose: This study was to evaluate the influence of tungsten carbide/carbon coating, which has superior hardness and frictional wear resistance, on the preload of abutment screws and the stability of coating surface after repeated closures. Material and method: The rotational values of abutment screws and the compressive forces between abutment and fixture were measured in implant systems with three different joint connections, one external butt joint and two internal cones. Moreover the stability and the alteration of coating surface were examined by comparison of the compressive force and the removable torque values during 10 consecutive trials, observation with scanning electron microscope and analyzed the elemental composition with energy dispersive x-ray spectroscopy Results and conclusion: 1. Application of coating resulted in significant increase of compressive force in all implant systems(P<.05). The increasing rate of compressive force by coating in external butt joint was gloater than those in internal cones (P<.05). 2. Coated screw showed the significant additional rotation compared to non-coated screw in all implant systems (P<.05). There were no significant differences in the increasing rate of rotation among implant systems (P>.05). 3. Removable torque values were greater with non-coated screw than that with coated screw (P<.05). 4. Coated screw showed insignificant variations in the compressive forces during 10 consecutive trials(P>.05) 5. After repeated trials, the surface layer of coated screw was maintained relatively well. However surface wearing and irregular titanium fragments were found in non-coated screw.

고분자 표면의 혈관내피세포 부착력에 관한 연구

최진욱,유규하,민병구,Choi, Jin-Wook,Ryu, Gyu-Ha,Min, Byoung-Goo 대한의용생체공학회 1990 의공학회지 Vol.11 No.1

To improve antithrombogenicity of polymer that used in vascular graft and artificial organs, seeding of human endothelial cells on the polyurethane was studied. Human endothelial cells were ismlated from human umbilical veins, using type I collagenase, and identified with goat anti vWF antibodies. Human endothilial cell seeding was tried upon the polyurethane which has good mechanical property and resists stresses. The hydrophobic polyurethane surface was changed hydrophilic by corona discharf:e treatment. Surface hydrophilicity was measured with Wilhemly plate method and the goniometer. To evaluate matrix protein adsorption, fibronectin adsorption test was done. To eveluate cell adhesion, human endothelial cell attachment forces were measured rising a perfusion chamber of , ism diamter. Less cells were detached from the hydrophilically treated polyurethane. This showed that corona discharge on the polyurethane could improve matrix adsorption and endothelial cell attachment.

하악골의 불연속 결손부 재건 시 비혈행화 장골이식술의 골흡수율에 관한 연구

최진욱,이충오,황희돈,김진욱,권대근,김진수,이상한,Choi, Jin-Wook,Lee, Chung-O,Hwang, Hee-Don,Kim, Jin-Wook,Kwon, Tae-Geon,Kim, Chin-Soo,Lee, Sang-Han 대한악안면성형재건외과학회 2012 Maxillofacial Plastic Reconstructive Surgery Vol.34 No.6

Purpose: Mandible resection and discontinuity defect created lead to aesthetic and functional problems. The iliac crest bone graft exhibits relative ease for bone harvesting, possibility of two team approach, ability to close the wound primarily, large amount of corticocancellous bone and relatively few complications. Whereas the use of free vascularized flaps has donor site morbidity and worse-fitting bone contour, the use of nonvascularized iliac bone graft has advantages in the operation time and patients' recovery time. So, nonvascularized iliac bone graft could be an attractive option. Methods: Twenty-one patients (M:F=1:1.1) underwent iliac crest bone harvesting for reconstruction of mandibular discontinuity defect (mean length : $61.6{\pm}17.8$ mm), from May 2005 to October 2011 at the Department of Oral and Maxillofacial Surgery in Kyungpook National University. The average age was $44.1{\pm}16.4$ years and the mean follow up periods was $28.2{\pm}22.7$ months. Bone resorption rate, according to age, sex, primary lesion, location and distance of defect, type of fixation plate, time of graft and pre-operative radiation therapy, were measured in each patient. Results: The mean bone resorption rate was $16.1{\pm}9.0%$. Bone resorption rate was significantly increased in mandibular defect that is over 6 cm in size (P=0.015, P<0.05) and the cases treated pre-operative radiation therapy (P=0.017, P<0.05). All was successfully fixed and maintained for the long-term follow-up. There were a few donor site complications and almost all patients were shown favorable outcome without severe bone resorption in this study. Conclusion: The nonvascularized iliac bone graft seems to be a reasonably reliable treatment option for reconstruction of mandibular discontinuity defects.

해외건설 수주경쟁력 향상을 위한 ODA (Official Development Assistance) 활용방안

최진욱,김재준,이한승,전낙근,Choi, Jin-Wook,Kim, Jae-Jun,Lee, Han-Seung,Jeon, Rak-Keun 한국건설관리학회 2007 건설관리 : 한국건설관리학회 학회지 Vol.8 No.5

The domestic construction market is recently daunted because of the sustainable real estate regulation policy by the government. In other aspect, after the WTO(World Trade Organization)system opened overseas construction is growing continuously with grow of international economy and opening of market through world. Therefor needs to establish strategy on expansion or over seas construction competitive power. The purpose of this research is expansion on over seas construction competitive power by suggesting project cost guarantee methods to Owner and cost guarantee methods are Official Development Assistance(ODA). Accordingly, this research analyzed a developed $country^{\circ}{\phi}s$ ODA and domestic ODA. Moreover, survey to Expert of related field about over seas construction and ODA for identified problems. Especially, based on the results it intends to analyzed domestic ODA competitive power and improve strategy to competitive power of receive an order on over seas construction. 정부의 지속적인 규제 정책으로 인해 국내 건설시장은 위축되어 있는 반면 해외 건설시장은 꾸준한 성장세를 보이고 있고, WTO(World Trade Organization)체제 출범 이후 국제적인 개방화가 가속되고 있다. 따라서 우리나라의 해외건설도 과거의 단순 입찰방식을 지양하고 해외건설 수주경쟁력 확대를 위한 전략 수립이 필요한 실정이다. 본 연구는 해외건설 분야에서 사업초기에서부터 발주처에게 프로젝트의 재원확보 방안을 제시함으로써 수주경쟁력을 증대시키는 것을 연구의 주제로 삼았으며 재원확보 방안으로 양허성(원조성격)을 지닌 공적개발원조(ODA)를 대상으로 하였다. 본 연구에서는 선진국 및 우리나라의 공적개발원조를 분석하고, 관련 분야 전문가를 대상으로 해외건설 및 공적개발원조에 대한 설문조사를 실시하여 현황 및 문제점을 알아보았으며, 이를 바탕으로 우리나라 공적개발원조의 경쟁력을 분석하고 해외건설 수주경쟁력 확대를 위한 전략을 제안하였다.

1996년 대전시 서북부에서 발생한 A형 급성 간염

최진욱,이경일,이동준,한지환,황성수,이경수,Choi, Jin-Ook,Lee, Kyung-Yil,Lee, Dong-Joon,Han, Ji-Whan,Hwang, Sung-Soo,Lee, Kyong-Su 대한소아감염학회 1997 Pediatric Infection and Vaccine Vol.4 No.1

목 적 : 과거 소아기 간염의 대부분을 차지하던 A형 간염은 경제 발전에 따른 보건 위생 상태의 호전으로 최근 소아에서 점차 성인으로 전환되는 추세이며 소아기에서 보기드문 질환이 되었다. 저자들은 치근 대전지역에서 발생한 A형 간염의 환아에 대한 임상 및 역학적 연구로 A형 간염에 대한 관심을 다시 주지하고 폭발적 발생 가능성에 대비하는데 도움을 받고자 하였다. 방 법 : 1996년 7월부터 1996년 12월까지 가톨릭대학교 대전성모병원에 입원한 급성 A형 간염환아 31명을 대상으로 하여 발생시기, 발생지역, 성별, 연령, 임상증상 및 검사실 소견 등을 후향적으로 조사하였다. 결 과 : 1) 발생시기는 7월, 8월, 9월에 각각 6례, 16례, 2례로 여름철에 주로 발생하였으며(76%), 10월에 1례, 12월에 6례가 발생하였다. 2) 발생지역은 대전 서구가 27례로 87%를 차지했으며 특히 도마동에서 18례(58%)가 발생 하였다. 3) 발병 연령은 3세 이하는 없었으며 4~5세가 3명, 6~10세가 13명, 11~15세가 15명이었고, 남녀의 비는 1.4:1이었다. 4) 입원시의 주된 증상(symptom)으로는 짙은 소변 (83%), 오심 및 구토(74%), 식욕부진 (68%), 상복부통(65%), 발열(54%), 피로감(41%)이었으며, 그외 소양감(22%), 두통(19%), 관절통(6%), 변비(6%), 설사(6%), 어지러움(3%) 등을 보였고 입원하기 전까지의 증상 지속기간은 펑균 5.3일이었다. 징후(sign)로는 황달(77%), 간비대(90%)와 비장비대(48%)가 촉진 및 초음파 검사로 관찰되었다. 5) 검사실 소견으로 입원시 AST, ALT의 굉균치는 각각 910IU/dl, 1239IU/dl, ALP (alkaline phosphatase)는 856IU/이었으며, 입원중 최고 총빌리루빈치의 평균치 5.6mg/dl(직 접 빌리루빈 4.8mg/dl)이었다. 대부분 1달 후 정상화 되었으며 심각한 합병증을 보인 증례 는 없었다. 결 론 : 소아에서의 A형 간염은 중한 합병증이 없이 회복되는 질환으로 우리나라에서도 오염원에 의해 전염성 A형 간염이 폭발적으로 발생(outbreak)할 수 있음을 알 수 있었다. A형 간염 항체의 역학적 연구를 통해 예방 접종의 필요여부 결정 및 오염원의 제거 등 예방에 대한 더 깊은 연구가 있어야 할 것으로 보인다. Purpose : Recently a shift in hepatitis A incidence from children to adults has been well noted. We experienced under 15-years old 31 patients who presented hepatitis A infection. In order to prepare for the prevention on hepatitis A outbreak in the future, we studied the clinical and epidemiologic manifestations of these patients. Methods : We enrolled patients from July to December in 1996 (6 months) and evaluated the monthly incidence, geographical distribution, age and sex, and clinical manfestations, including laboratory fadings. Results : Many cases of hepatitis A occured in the summer months, especially August (16/31 cases). Most of patients (87%) were living in the Seo-Ku area (northwest district of the city). In age distribution, there were no cases under 3 years of age, 3 cases from 4~5 years, 13 cases from 6~10 years, 15 cases from 11~15 years. Clinical profiles showed that dark urine, nausea and vomiting, anorexia, abdominal pain, fever, and fatigue were the common presenting symptoms. The initial presenting laboratory tests included total bilirubin 3.3mg/dl, alkaline phosphatase of 856units/L, and serum asparate aminotransferase and alanine aminolransferase levels of 910IU/L and 1239IU/L, respectively. No patient presented atypical clinical courses or complications. Conclusions : Hepatitis A in children shows benign clinical features. This study showed that the possibility of another outbreak of Hepatitis A in the TaeJon area or elsewhere in the near future Korea will be possible. To prevent an outbreak we will be concerned about the anti-HAV IgG prevalance rate in children and preventive modalities including vaccination against hepatitis A.

154 kV급 HTS 케이블의 절연설계 및 굴곡시험

최진욱,최재형,임응춘,김해종,조전욱,김상현,Choi, Jin-Wook,Choi, Jae-Hyeong,Lim, Eung-Choon,Kim, Hae-Jong,Cho, Jeon-Wook,Kim, Sang-Hyun 한국전기전자재료학회 2008 전기전자재료학회논문지 Vol.21 No.11

It is important that study on cryogenic electrical insulation design to develop the cold dielectric(CD) type HTS cable because the cable is operated under the high voltage environment in cryogenic temperature. This paper proposes two types of insulation design to carry out the maximum insulation design for 154 kV-class HT cable. The proposed insulation design method takes into consideration AC and lightning impulse withstand voltage so as to prevent AC breakdown for power frequency operating voltage during operating the cable and breakdown for lightning impulse voltage. The final insulation thickness is determined by selecting high value out of two insulation thickness calculated through the two insulation design methods. And we researched electrical insulation characteristics of HTS cable according to bending ratio and the number of bending.

Adaptive Statistical Iterative Reconstruction 기법을 이용한 Bone SPECT/CT 검사에서 피폭량 감소 방안

최진욱,최현준,박찬록,조성욱,김진의,이재성,이동수,Choi, Jin-Wook,Choi, Hyeon-Jun,Park, Chan-Rok,Cho, Sung-Wook,Kim, Jin-Eui,Lee, Jae-Sung,Lee, Dong-Soo 대한핵의학기술학회 2014 핵의학 기술 Vol.18 No.1

ASIR기법은 statistical noise modeling을 사용하여 CT image를 reconstruction하는 방법으로, mA를 낮춰도 이미지 질을 보전하며 noise reduction 효과가 있다고 알려져 왔다. 본 논문은 본원에서 주로 하는 bone SPECT/CT에 ASIR 기법을 적용하여 이미지를 평가하였다. GE의 Discorvery 670을 이용하여 120 kVp, 100 mA를 기준으로 mA를 변화시켜서 ASIR의 적용 전과 적용 후 영상을 비교하였다(ASIR level: 20-80%). Anthropomorphic phantom으로 ASIR (%)의 변화에 따른 SPECT image의 감쇠 보정 정도를 측정하였다. 두번째로 ACR phantom으로 CT image의 CNR, image noise, spatial resolution을 평가하였다. 세 번째로 lower torso phantom을 이용하여 spine에 최적화할 수 있는 ASIR level을 선택한 후 2명의 bone SPECT/CT follow up 환자에게 ASIR를 적용하여 영상을 획득한 후 5년 이상의 경험이 있는 10명의 방사선사에게 blind test를 시행하였다. SPECT의 영상의 감쇠 보정 정도는 ASIR의 변화와는 무관하게 모두 유의한 차이가 없었다(P>0.05). ASIR을 적용했을 때 CT image의 noise는 mA의 변화에 따라 최소 17%에서 최대 52%까지 감소하였다. ASIR를 적용하지 않았을 때 CNR은 40 mA에서 0.42를 보여준 반면 ASIR를 적용한 40 mA (ASIR 60%)에서도 0.8 이상을 유지하였다. High contrast 영역의 비교에서는 ASIR 적용과 상관없이 40 mA까지 12 lp/cm 영역을 구별할 수 있었다. Lower torso phantom의 spine image에서 100 mA image와 육안적으로 비슷한 ASIR level은 60% (40 mA) 정도였고, bone SPECT/CT에 적용한 후 blind test에서 육안적으로 ASIR를 적용하지 않았을 때와 차이를 구별하지 못하였다. 본 논문의 결과는 SPECT/CT에서 ASIR 기법을 사용했을 때 SPECT와 CT image의 특별한 영상의 질 저하 없이 radiation dose를 줄일 수 있다는 것을 보여준다. 또한 관심부위가 bone에 한정되어 있는 bone SPECT/CT 특성상 더 높은 ASIR level도 가능할 것으로 사료된다. Purpose: Adaptive statistical iterative reconstruction (ASIR) technique is a reconstruction method of CT image using statistical noise modeling which is known to reduce image noise and to preserve image quality despite reducing radiation dose. The aim of this study is to evaluate images using ASIR on bone SPECT/CT which is primarily performed in our hospital. Materials and Methods: We compared the images of applied ASIR (ASIR level: 20-80%) and none ASIR by changing the mA based on 120 kVp, 100 mA using Discovery NM/CT 670 (GE, U.S.A). First, we evaluated attenuation correction in SPECT image by changing the ASIR level using Anthropomorphic phantom. Second, we compared the contrast to noise ratio (CNR), image noise and spatial resolution in CT image using ACR phantom. Third, after selecting the ASIR level applicable patient using lower torso phantom, we examined 2 patients who followed up bone SPECT/CT and we performed blind test. Results: The degree of attenuation correction in SPECT image showed no significant difference between applied ASIR and none ASIR (P>0.05). When applied ASIR, the noise of CT image were reduced at least 17 up to 52% by changing the mA. The CNR of image with ASIR was maintained more than 0.8 at 40 mA (ASIR 60%) while those without ASIR showed 0.42 at standard 40 mA. In comparison of the high contrast object, we distinguished 12 line pairs/cm at 40 mA regardless of appling ASIR. Comparison of the patients image applied ASIR level 60% (40 mA) which found out by spine image of lower torso phantom showed no signigicant difference between applied ASIR and none ASIR in blind test. The CTDIvol and DLP for applied ASIR 60% showed decreased by 60%, 60% on average than using standard mA. Conclusion: The study show that the radiation dose in SPECT/CT using ASIR can be reduced despite degradation of SPECT and CT images. In addition, higher ASIR level could be possibly applied characteristics of SPECT/CT that region of interest is limited to bone.

갑상선 종양에서 Heat Shock Protein70과 Heat Shock Protein90의 발현 양상

최진욱,김진영,박철영<SUP>1<.SUP>,오기원<SUP>1<.SUP>,임성희<SUP>1<.SUP>,박성우<SUP>1<.SUP>,조현득<SUP>2<.SUP>,이명준<SUP>3<.SUP>,김이수,Jin Wook Choi,M.D.,Jin Yong Kim,Cheol Young Park,M.D.<SUP>1<.SUP>,Ki Won Oh,M.D.<SUP>1<.SUP> 대한갑상선-내분비외과학회 2004 The Koreran journal of Endocrine Surgery Vol.4 No.2

Purpose: Heat shock proteins (hsps) are synthesized by cells in response to various stress conditions, including carcinogenesis. The expression of hsps in neoplasia has been implicated in the regulation of cell signaling pathway such as cell survival and apoptosis. This study aimed to determine whether hsps expression in various thyroid neoplasia are significant and to identify the possibility as a therapeutic molecular target. Methods: We examined the expression of the hsp70 and hsp90 on tissue section from 53 thyroid tissues (16 normal tissues; 11 nodular hyperplasia; 12 follicular adenomas; 14 papillary carcinomas) using immunohistochemistry. Hsps expression was scored according to the percentage of positively stained cells (grade 0 to grade III). Results: For hsp70, all of the 53 tissues showed over- expression. 100% (16/16) of normal thyroid tissue and 87.0% (20/23) of benign tissue were categorized as grade I or II. In comparison, the carcinoma tissues showed expression in 64.3% with grade III. For hsp90, almost of normal thyroid tissue and benign tumors showed no expression (87.5% in normal tissues, 91.3% in benign tumors). However, all of carcinoma tissues showed expression and 78.6% (11/14) of carcinoma were in grade II or III. Conclusion: In current study, the pattern of expression for hsp70 and hsp90 in normal, benign, malignant thyroid tissues suggests that heat shock proteins might have some role in tumorigenesis in thyroid. Since there have been no reports on heat shock proteins and thyroid, further study is necessary and could give us clinically significant clue for diagnosis and treatment. (Korean J Endocrine Surg 2004; 4:79-84)

파라계 아라미드 섬유의 열처리에 따른 구조, 물성 상관관계

최진욱,지민호,이민호,이진수,백두현,Choi, Jin-Uk,Jee, Min-Ho,Lee, Min-Ho,Lee, Jin-Soo,Baik, Doo-Hyun 한국섬유공학회 2010 한국섬유공학회지 Vol.47 No.1

The structure-property relation of para-aramid fibers heat-treated under various conditions was investigated. The effect of heat-treatment on the mechanical properties of the fibers was also studied. Tensile strength and strain at break decreased and tensile modulus increased with increasing heat-treatment temperature. Tensile modulus also increased with increasing draw ratio. Structural characterization was carried out by using wide angle X-ray scattering (WAXS) method. Both the apparent crystal sizes (ACS) measured from the broadening of reflection peaks of (004), (110) and (200) planes and the orientation angle obtained from azimuthal scan along the (200) direction were found to increase with increasing heat-treatment temperature and draw ratio.