민감도해석을 이용한 다중 쎌 구조형 날개의 최적설계

辛相勳,金斗萬,林慶鎬 한국항공대학교 1991 論文集 Vol.29 No.-

현재 항공기 구조는 Semi-monocoque구조 형식을 택하며, 날개구조에서는 Box Beam형 날개구조를 택한다. 본 연구에서 날개구조 해석은 "Flange는 축하중을 담당하고, 비틀림과 전단력은 Shear web가 담당한다"는 가정에 적합한 "Shear Web Beam 유한요소"라는 유한요소를 사용하여 응력해석을 하였고, 중형 항공기의 날개구조로 많이 사용되는 다중 쎌 구조를 택하여 처짐과 응력의 제한 조건이 있는 상황에서 민감도 해석을 이용하여 설계최적치인 플랜지의 단면적과 웨브의 두께를 구함으로써 Box Beam날개구조물의 무게를 최소화 하였다. This paper presents development of a optimal structural design technique for Multi-Cell Box beam type wing senditivity analysis which is implement into finite element program. Multi-Cell Box Beam type wing of Semi-monocopue structure is analyzed by finite element method with 'Shear Web Beam' finite element. The element consists of a shear panel that is subjected to constant shear flow and four flanges along the four sides of shear panel. Flanges are subjected to linearly varying axial force. Most nonlinear programming technique for structural optimization require carring out the design sensitivity analysis for objective function and constraints i.e. computing the gradients of displacement, stress with respect to design variables. The flange area and web thickness are determined that minimized the total weight of the Multi-Cell Box Beam type wing using developed technique and computer program.

각화낭성치성종양의 재발과 연관된 p53, Ki-67, PCNA 및 cytokeratin 17, cytokeratin 18의 발현

신상훈,성화식,이승환 부산대학교 병원 암연구소 2008 부산대병원학술지 Vol.- No.24

The keratocystic odontogenic tumor(OKC) represents approximately 11% of odontogenic cysts and is decided by microscopic and histopathologic determinant rather than by clinical apprearance. The OKC is noted for its capacity to recur after treatment. In this study, p53, Ki-67, PCNA and cytokeratin 17, cytokeratin 18 expression of OKC in relation to non-recurrenct lesion and recurrent lesion after cyst enucleation were examinated. The p53, Ki-67, PCNA and cytokeratin 17, cytokeratin 18 antibody staining were used. The obtained results were as follows. In proliferating rate of non-recurrent OKCs and recurrent OKCs using p53, Ki-67 and PCNA staing, there was not significant difference. In cytokeratin 17 staining, strong positive reaction was showed in all layers of recurrent OKCs rather than non-recurrent OKCs. In cytokeratin 18 staining, negative or weakly positive reaction was showed in recurrent OKCs rather than non-recurrent OKCs. In summary, it was suggested that the recurrence of OKCs was not related to proliferating rate of epithelium and the prognosis of the recurrence of OKCs is helped using cytokeratin 17 and cytokeratin 18.

하악골 전돌증 수술 후 하악골 이동량에 따른 발음 양상에 관한 비교 연구

신기영,이동근,오승환,성헌모,이숙향 대한악안면성형재건외과학회 2001 Maxillofacial Plastic Reconstructive Surgery Vol.23 No.1

After performing mandibular setback surgery, we found some changes in patterns and organs of speech. This investigation was undertaken to investigate the aspect and degree of speech patterns according to the amount of surgical setback in mandibular prognathic patients. Thirteen patients with skeletal Class Ⅲ malocclusion were studied preoperative and postoperative over 6 months. They had undergone the mandible setback operation via bilateral sagittal split ramus osteotomy(BSSRO). We split the patients into two groups. Group 1 included patients whose degree of mandibular setback was 6mm or less, and Group 2 above 6mm. Control group was two adults wish normal speech patterns. A phonetician performed narrow phonetic transcriptions of tape-recorded words and sen- tences produced by each of the patients and the acoustic characteristics of the plosives, fricatives, and flaps were analyzed with a phonetic computer program (Computerized Speech Lab(CSL) Model 4300B(USA) ). The results are as fallows : 1. Genera1ly, Patients showed longer closure duration of plosives, shorter VOT(voice onset time) and higher ratio of closure duration against VOT 2. Patients showed more frequent diffuse distribution than the control group in frication noise energy of fricatives. 3. In fricatives, frequency of compact from were higher in group 1 than in group 2. 4. Generally, a short duraction of closure for /ㄹ/ was not realized in the patient's flaps. Instead, it was realized as fricatives, sonorant with a vowel-like formant structure, or trill type consonant. 5. Abnormality of the patient's articulation was reduced, but adaptation of their articulation after surgery was not perfect and the degree of adaptation was different according to the degree of surgical setback.

가새의 위치를 고려한 튜브 구조물의 횡적거동에 관한 연구

신수미,이정훈,박성수 釜山大學校生産技術硏究所 2002 生産技術硏究所論文集 Vol.61 No.-

본 연구는 수평하중 하에서의 가새 튜브 구조 시스템의 거동을 분석하기 위하여 기본 골조 튜브 모델에 위치가 다른 가새를 추가한 가새 튜브 모델에 대한 해석을 수행하였다. 구조해석은 3차원 탄성해석 프로그램인 MIDAS GENw를 사용하여 수행하였으며, 구조 해석을 수행한 후, 각각의 거동 특성을 비교 분석하여 가새의 특성에 따른 횡변위 감소 효과 및 전단지연 현상의 완화를 고찰하고자 한다. The braced tube structure is a solution to increasing the efficiency of the framed tube structure, which is to add the substantial diagonal bracing to the faces of the tube. Due to additional braces, the flexural rigidity of structure is increased and the shear lag effect is decreased. Therefore the structure behaves like a cantilever tube. To analyze the behavior of the braced tube structure under the lateral load, the braced tube model, which adds diagonal members of the various characteristics - location, shape, stiffness - to the framed tube model, is used.

스트렙토조토신으로 유도된 당뇨 백서에 티타늄 임프란트 매식 후 주위 골형성에 관한 연구

신상훈,김종렬,박봉수 대한악안면성형재건외과학회 2000 Maxillofacial Plastic Reconstructive Surgery Vol.22 No.5

Use of osseointegrated implants for missing teeth has been widely utilized in clinical dentistry. Allthough the procedure has been highly successful, there have also been unavoidable failures. The success of osseointegration depends in part on the host bone and its healing capacity, and concerns have been raised about various conditions affecting its quality and quantity. Diabetes mellitus, which is a major health problem for the elderly, represents a reduction in collagen synthesis, delayed wound healing and osteoporosis. The underlying clinical problem is a deficiency of bone mass. Because age and gender are reported to be an important risk factor for diabetes mellitus, the rate of implant loss caused by failure of osseointegration may also be expected to increase correspondingly. Thus, a large population of the target population for dental implants may have a high risk for implant failure. There are, however, few histologic reports regarding tissue reaction to implants in diabetes patients. Streptozotocin is the current diabetogenic agent of choice for producing experimental diabetes mellitus. The toxic acts specifically on the β- cells of the pancreas and the metabolic conditions which result from the use of streptozotocin are reported to resemble those observed in humans. The purposes of this study were to histologically examine the tissue reaction to titanium implants inserted into the tibiae of streptozotocin induced diabetic rats using light microscopy and to assess over time the quantitative differences between the newly formed bone of diabetes-induced rats and controls using image processing systems and immunohistochemistry with fibronectin and CD44 antibody. Seventy adult rats of both sexes were used in this study. In thirty-five rats, streptozotocin was injected intraperitoneally to induce diabetes and the serum glucose concentration was checked to ensure the induction of diabetes prior to implant placement and at the time of sacrifice. The titanium screw implants (diameter, 2.0mm; height, 3.5mm) were inserted into left tibiae of 70 rats, 35 in the control group and 35 in the DM group. The experimental rats were sacrificed at different time interval(1st, 2nd, 3rd, 4th, 6th, 8th and 12th week) for histologic examination, histomorphomeric analysis and immunohistochemistry with fibronectin and CD44 antibody. The results obtained from this study were as follows : 1.A rapid bone formation was observed in control group compared with DM group based on histological examination. However the pattern of bone formation in both groups was similar. 2.According to the histomorphometric analysis, the control group showed significantly higher in marrow bone density, marrow bone-implant contact ratio, and total bone-implant contact ratio compared with DM group. 3.The level of fibronectin expression was the most abundant at 3 and 6 weeks, which maintained to 6 and 12 weeks in control and DM group, respectively. From 8 weeks, the level of fibronectin expression decreased gradually in control but not in DM group. 4.The level of CD44 expression was the most abundant at 4 weeks, which decreased gradually to 12 weeks in control group while high level of CD44 expression was observed with no significant change to 12 weeks in DM group. From these results, it could be stated that although the rate of bone formation was delayed in DM group, dental implant procedure was not a contraindication and longer healing period was necessary in diabetes mellitus.

응급실을 내원한 구강악안면외과 안면골 골절 환자의 변화에 대한 비교 연구

신상훈,성화식,강영훈,황대석,김용덕,김욱규,김종렬,정인교 부산대학교 병원 암연구소 2008 부산대병원학술지 Vol.- No.24

Although there have been many clinical studies about the facial trauma in the recent as well as in the past, severity and frequency of facial trauma are reported multifarious. It seemed to be because of variety of social, cultural, and environmental factors, and the view point of investigators. In this study, we investigated about the patients visiting emergency room during recent 4 years(2004-2007), and compared with retrospective study during former 10 years(1992-1996, 1999-2003) in Dept. OMS Pusan National University Hospital. We assessed the cause, type, demographic, etc, and analyzed alterations of facial bone fractures during past 3 periods. The results were as follows. The total number of patients was increased. 429 patients treated for maxillofacial fractures between January 1992 and December 1996, 466 patients treated between January 1992 and December 1996 and 764 patients treated between January 2004 and December 2007. The male-to-female ratio were 4.6:1, 3.9:1, and 4.16:1, respectively. Patient in the age groups of 10-19 years and 20-29 years increased in the latter two periods. Assaults and falls are decreased gradually, but slip down s are increased. Traffic accidents are still major cause of facial trauma. The mandibular fractures showed the highest incidence thorought three periods. Symphysis fractures of mandible was increased and condyle fractures of mandible was drecreased in the third period.

하악측두관절에서 퇴행성 관절염의 실험모델 개발

신상훈,송동석,김철훈,황대석,김용덕,김욱규 부산대학교 병원 암연구소 2007 부산대병원학술지 Vol.- No.21

Purpose : The purpose of this study is to investigate temporomandibular joint arthritis that was induced by intra-articular injection of collagenase in rabbits. Material and Methods: In this study, 12 rabbis was used. We injected collagenase on temporomandibular joint of rabbit and observed for six weeks. H-E stain was done. Results : Four weeks later from 2.0 mg collagenase injection, we observe histologic appearance like arthritis. Conclusion : In our study using injection of collagenase in temporomandibular joint of rabbit we produce arthritis on temporomandibular joint of rabbit.

하악과두에 발생하는 골연골종의 진단학적 방법

신상훈,차승만,황대석,김용덕,김욱규 부산대학교 병원 암연구소 2006 부산대병원학술지 Vol.- No.20

Pulpose : Osteeochondroma is a common benign tumor of the axial skeleton, especially the distal metaphysis of the femur and the proximal metaphysis of the tibia, however, is\ occured rarely on the facial skeleton. Tumors of the mandibular condyle are various and rare. so common interest is a little and its clinical symptoms are similar to the others. therefore, early diagnosis is very difficult. In this study, we will present our cases and review the literatures. Patients and Methods: We studied 17 patients(8 males, 9 females) who were diagnosed a osteochondroma of the mandibular condyle in the department of oral and maxillofacial surgery, Pusan National University Hospital. We reviewed the medical records. Results : Patients' mean age was 30.05 years. The sexual distribution is almost same. Twelve left condyles and five right condyles were involeved. The main symptoms was noise and facial asymmetry. Conclusion : Osteeochondroma is a rare benign tumor of the mandibular condyle. The differential diagnosis is difficult. However, using CT and MRI, we diagnosed early the osteochondroma and treated properly. Thus, we presented the cases of the osteochondroma with the literature reviews.

정반 평면도 평가를 위한 측정점의 합리적인 개수의 결정

신상철,현창헌,박흥식 江原大學校 産業技術硏究所 1998 産業技術硏究 Vol.18 No.-

The flatness is the most important nature for the surface table. For finding such a flatness, the surface is surveyed along a number of straight lines parallel to the edges of table, which form a grid. Next, the variations in height of the grid points are measured relative to a datum point. If the number of such points is increased. It is not necessarily to use many grid points for finding the original flatness ofa measured surface tabel. So it is necessary to find the rational quantity of such grid points. It is found that about 220 points per 1 m? of surface tabel for measurement is the rational quantity with less than about 15% error of the original flatness.

소아의 구강내에서 검출된 Streptococcus viridans에 대한 항균제 감수성 연구

신상훈,송정호 대한악안면성형재건외과학회 2000 Maxillofacial Plastic Reconstructive Surgery Vol.22 No.3

A large number of streptococci that do not fit readily into any of the established classification schemes have been relegated to a large heterogeneous group called the Streptococcus viridans, which are members of the normal flora of the mucous membranes of the body, including the oral cavity, the nasopharynx, and genitourinary tract. This group includes S. mitis, S. oralis, S. sanguis, S. salivarius, S. milleri, etc. Surveying on the literature, it has been reported that infective endocarditis, meningitis, rhabdomyolysis, cholangitis, appendicitis caused by Streptococcus viridans, which were the most important pathogen in children with malignant hematologic disease. Various antibiotics has been chosen for treatment or prophylaxis for these infections, but were generally lower antimicrobial susceptibilities because of an abuse of antibiotics and advent of resistant group. Therefore, surveillant culture must be performed to evaluate personal antimicrobial susceptibilities of intraoral microbes for proper antimicrobial choice for dental procedures . This study examined sampling from subgingival plaque of 60 chidren's microbes. The cultured bacterial isolates, Streptococcus viridans were examined 10 antimicrobial drugs with the Kirby-Bauer agar disk diffusion method. The used drugs were Penicillin, Ampicillin, Oxacillin, Cephalothin, Imipenem, Gentamicin, Erythromycin , Vancomycin , Ciprofloxacin , Clindamycin. The results were as follows : 1.Sampling Streptococcus viridans were S. mitis(65%), S. oralis(22%), S. sanguis(5%), S. intermedius(3%), S. salivarius(2%), S acidominimus(2%), Unidentified streptococcus(2%). 2.The antimicrobial susceptibility of total Streptococcus viridans : Oxacillin< Erythromycin< Pencillin=Ciprofloxacin< Cephalothin<Ampicillin< Clindamycin< Gentamicin< Imipenem =Vancomycin. 3.The antimicrobial susceptibility of S. mitis : Oxacillin=Erythromycin< Ciprofloxacin< Cephalothin<Penicillin = Ampicillin< Gentamicin< Clidamycin< Imipenem = Vancomycin. 4.The antimicrobial susceptibility of S. oralis : Oxacillin< Erythromycin< Penicillin=Ciprofloxacin=Clindamycin< Cephalothin = Gentamicin< Ampicillin< Imipenem =Vancomycin. 5.There was no significant difference in the antimicrobial susceptibility among each Streptococcus viridans group.