마멸입자 형태해석에 의한 유압피스톤용 모터의 상태감시

문병주,조연상,박흥식,전태옥 韓國工作機械學會 2000 한국생산제조학회지 Vol.9 No.6

Morphological analysis of wear particles is one of useful methods for machine condition monitoring because it is well reflected in machine driving state. This paper was undertaken to apply to the condition monitoring of hydraulic piston motor. The lubricating wear test was performed under different experimental conditions using the wear test device and wear specimens of the pin on disk type was rubbed in paraffinic base oil by three kinds of lubricating materials, varying applied load, sliding distance. The four shape parameters (50% volumetric diameter, aspect, roundness and reflectivity) arc used for morphological analysis of wear particles. The results showed that the four shape parameters of wear particles depend on a kind of the lubricating materials. It was capable of calculating presumed wear volume for three kinds of mate-rials on driving time to foresee a damage condition of lubricating materials.

수은폭로 근로자의 조기 신기능 장해 지표로서의 요중 β-Galactosidase 활성도에 관한 연구

오연희,김광종,천병철,박종태 大韓産業醫學會 1995 대한직업환경의학회지 Vol.7 No.1

The objective of this study was to evaluate the relationship between β-galactosidase activity in urine, in serum and urinary N-acetyl-β-glucosaminidase activity as an early indicator of renal effect and mercury concentration in urine and blood, reflecting the intensity of exposure to or the amount of body burden of mercury. This study was carried out among 70 workers exposed to mercury vapor and 63 non-exposed workers as a reference. The results were as follows; 1. The mean concentration of urinary mercury(43.5 ㎍/l) in exposed subjects was about nine times higher than that of non-exposed subjects, but the mean values of blood mercury were not different from each other. 2. The mean values of β-galactosidase activity in urine(119.7μmolMU/h/g creatinine) and in blood(73.7 molMU/h/l) of mercury-exposed subjects were significantly higher than those of non-exposed subjects. 3. In mercury-exposed subjects, β-galactosidase activities in urine(r=0.38, P<0.01) and in serum(r=0.26, P<0.05) were correlated to urinary mercury concentration, but not to blood mercury concentration. The urinary excretion of β-galactosidase activity was closely associated with urinary mercury concentration in the result of the multiple regression analysis. 4. The urinary β-galactosidase activity in exposed subjects increased as the urinary mercury increased, and in the exposed subjects with more than 50㎍/l of urinary mercury was highly related to urinary β-galactosidase activity(r=0.47, P<0.05). 5. Among exposed subjects with more than 50㎍/l of urinary mercury, 20.0% of them showed abnormal value of urinary β-galactosidase activity.

Fractal 차원에 의한 표면경화면과 마찰면의 형태해석

문병주,조연상,옥철호,박흥식,전태옥 동아대학교 생산기술연구소 2001 生産技術硏究所硏究論文集 Vol.6 No.1

The determination of surface middleography is believed to be extremely important in the areas of contact mechanics, adhesion and friction. In order to describe middleography of various rubbed and hardened surface, the wear test was carried out under different experimental conditions in dry friction. And fractal descriptors was applied to rubbed and hardened surface of laser modified steel with image processing system. These descriptors to analyze surface structure are fractal dimension. Surface fractal dimension can be determined by sum of intensity difference of surface pixel. middleography of rubbed and hardened surface can be effectively obtained by fractal dimensions.

수술적으로 치료한 통증을 동반한 흉추부의 후외상성 Schmorl씨 결절 : 2례 보고 Report of Two Cases

신병준,이재철,송화용,정석봉,권계원,조영일,김연일 순천향의학연구소;Soonchunhyang Medical Research Institute 2004 Journal of Soonchunhyang Medical Science Vol.10 No.2

Study Design : Two patients who had painful Schmorl's node at thoracic level from acute trauma were adopted and taken operation for its treatment Objectives : To document the effect of operation for the treatment of painful Schmorl's node at thoracic level summary of background data : Schrmorl's nodes are common spinal lesion generally believed to be asymptomatic, but in some cases there were painful symptom by Schmorl's node. This case report is to explain the effect of operative treatment for the painful Schmorl's node. Methods : Two patients were adopted who had traumatic painful Schmorl's node at thoracic level for our case report. They were treated conservative methods at first but it's effect were poor, so they were taken anterior decompression and fusion, and checked back pain symptom. Result : In all two patients, the symptom of back pain by Schmorl's nodes at thoracic level was almost subsided. conclusion : For the treatment of traumatic painful Schmorl's node, most of surgeon says that conservative treatments were treatment of choice, but operative treatments are also benefit to subsidence of back pain by Schmorl's node.

퇴행성 요추 질환의 후방 수술시 발생한 경막 손상

신병준,이재철,조영일,최원기,허일,김경제,김연일 대한척추외과학회 2003 대한척추외과학회지 Vol.10 No.3

하악 절치부에 발생한 과잉치

마연주,이제호,송제선,최병재,김성오 大韓小兒齒科學會 2009 大韓小兒齒科學會誌 Vol.36 No.4

소아치과 영역에서 치아수의 이상은 흔히 관찰할 수 있으며, 그 중 대표적인 것의 하나가 과잉치이다. 과잉치의 발생원인에 대해서는 여러가지 가설이 있으며 유전적 또는 환경적 요인에 의해 치배 형성기의 정상 치판이 과도하게 증식하여 발생되는 것으로 알려져 있다. 과잉치가 가장 흔하게 발생되는 부위는 상악에서는 절치부로 그 빈도는 80-94% 정도로 보고되고 있고 그 다음으로는 구치부와 소구치부 순서로 나타난다. 상악에 비해 하악에서는 대부분 소구치 부위에서 발생되며 절치부에서는 전체 과잉치 발생빈도 중 단지 1-2% 이하로 매우 낮은 빈도로 발생되는 것으로 보고되고 있다. 이 증례는 드물게 나타나는 하악 절치부에 2개의 과잉치가 있다는 주소로 내원한 만 6세 남아에서, 임상 및 방사선학적 검사 결과 하악 절치부에 정상치와 크기와 형태가 비슷한 정상치형의 과잉치 2개를 포함하여 6개의 절치가 존재하는 것이 관찰되었다. 발치할 치아의 정확한 진단 및 결정을 위해 컴퓨터 단층 촬영을 시행하였고 발치 후 하악 전치부의 정상적인 배열을 위해 치아 맹출에 대한 주기적 정기 검진 후 교정적 평가와 치료를 진행할 예정이다. Pediatric dentists often meet children with abnormal in number of tooth. Presence of supernumerary teeth is frequent cause of malocclusion. Etiology for supernumerary teeth is not yet clearly defined, but it is thought to be caused by excessive proliferation of dental lamina by hereditary and environmental factors. Supernumerary teeth occur in the maxilla nine times more frequently than in the mandible. Most common supernumerary tooth is the mesiodens in the maxilla, and some are observed in the maxillary molar and mandibular premolar. It occurs rarely in the mandibular incisor region with the incidence of 1-2% among all supernumerary teeth. A six-year old boy visited the department of the pediatric dentistry, Yonsei University Dental Hospital, with the chief complaint of crowded supernumerary teeth on the mandibular incisor region. Clinical and radiographic examinations revealed six permanent mandibular incisors similar in size, shape, and length. Further investigation using computed tomography(CT) was proceeded on the mandible to measure and compare morphologic features and positions of the six incisors. Then, we decided to remove two incisors which were already erupted. Periodic check-up was followed to monitor the dental development and spontaneous positional enhancement of the remaining four incisors in the mandible.

설측으로 수평 맹출한 하악 측절치의 교정적 견인

김성오,마연주,손흥규,최병재,이제호 大韓小兒齒科學會 2010 大韓小兒齒科學會誌 Vol.37 No.1

Tooth eruption is the movement of the tooth from the developing place in the alveolar bone to the functional position in the oral cavity. The permanent incisors originate from the dental lamina on the lingual side of preceding deciduous tooth and erupt to the level of the occlusion through the well developed gubernacular cord. Ectopic eruption is a developmental disturbance in the eruption pattern of the permanent dentition. Most of the ectopically erupted lower incisor has been found in lingual side. The ectopically erupted tooth could be repositioned by orthodontic force in the early mixed dentition, which could help preventing the problems of loss of space and the lingual tilting of the lower anterior teeth. An eight-year-old girl visited the department of pediatric dentistry, Yonsei Dental University Hospital, for the evaluation and the treatment of the lower right lateral incisor, which was horizontally erupted in the lingual side, parallel to the mouth floor. Her tongue was placed on the labial side of that tooth. There was no previous dental history of dental caries or trauma on the pre-occupied primary incisor. Clinical and radiographic examinations including the computed tomography(CT), showed no evidence of dilacerations on root. Therefore, we decided to start active orthodontic traction of the lower right lateral incisor. We designed the fixed type of buccal arch wire and the lip bumper with hook for the traction. Button was attached to the lingual side of the ectopically positioned tooth. Elastic was used between the appliance and the button on that tooth. After the tooth become upright over the tongue level, appliance was change to the removable type and periodic check-up with occlusal guidance was followed to monitor the position of the tooth. In this case using the fixed appliance with modified form of lip bumper and hook embedded in acrylic part instead of extraction was very efficient up-righting the ectopically erupted tooth toward the occlusal plane. 치아 맹출이란 치아가 치조골 내의 발생 장소에서부터 교합면쪽으로 이동하여 구강 내로 출현한 후 치아의 기능적 위치까지 이동하는 것을 말한다. 유치의 치근부에서 발육하는 영구치배는 천천히 유치의 치근과 지지하는 치조골 부위를 흡수하면서 맹출하고, 이와 동시에 영구 치배의 치근과 치조골 및 기저골을 성장시킴으로써 영구치의 지지부위가 확립된다. 대개 영구전치의 치배는 유전치의 치근단 설측에 위치하는데 잘 발달된 도대삭(gubernacular cord)을 따라서 교합면상으로 맹출하게된다. 이소 맹출이란 일반적으로 치배가 본래 발생 위치에서부터 예상되는 정상 맹출경로에 이상이 있는 것을 말한다. 즉, 치아가 치조골 내 발생 위치에서 예측되는 정상맹출 경로를 벗어나 맹출하는 것이다. 그 중 하악 측절치의 이소 맹출의 경우 치아의 위치를 바로잡는데 있어서, 그 치료 시기가 중요한 요소로 여겨지는데 일반적으로 혼합치열기 초기가 바람직한 치료시기이다. 하악전치가 이소 맹출한 경우 적절한 시기에 치료를 시행함으로써 공간 소실의 문제나 하악 전치부의 설측경사 등의 문제가 발생하는 것을 예방할 수 있다. 본 증례는 만 8세 여아에서 혀 아래쪽의 구강저 부근에 수평방향으로 이소 맹출하는 하악 우측 측절치를 주소로 연세대학교 치과대학병원 소아치과에 내원하였다. 컴퓨터 단층촬영(CT)을 이용하여 문제 치아의 치근 만곡 정도를 확인한 후, 혼합 치열기 초기에 lip bumper와 buccal arch를 이용하여 26주간 적극적인 견인적 처치를 시행하였다. 결과적으로 이소 맹출한 측절치를 본래 위치로 이동시켰으며 나머지 영구치의 맹출에 대한 관찰 및 평가 후 전반적인 교정치료를 진행하기로 계획하였다.

최근 5년간 급성 A형 간염으로 입원한 환자들에 대한 입원 내용 분석

장재영,유병욱,조용진,오정은,홍성호,조주연 순천향대학교 의학연구소 2009 Journal of Soonchunhyang Medical Science Vol.15 No.1

Abstract Background : Due to improvements in Korea's sanitary conditions, antibody rates to the hepatitis A virus is decreasing rapidly and admission due to the disease is increasing, Patients who were admitted for hepatitis A during the last 5 years were selected and yearly differences in admission, clinical picture, medical fees, and differences according to age and gender were analyzed. Methods : Patients who were admitted to the Seoul Soonchunhyang University Hospital during the 5 year period between May of 2003 and April of 2008 and tested positive for IgM anti-HAV were selected and their medical records retrospectively analyzed. Results : 156 subjects [91 male (58%), 65 female (42%) were selected. The average age was 29.2 years (range; 21.4-37), average admission period 12.6 days (range; 12.5-1 7.7) days, and average medical fees 2,295,151 (range; 932,097-3,658,205) KRW(Korean Won), Yearly incidence rates were as follows : 10 for May, 2003 to April, 2004, 14 for May, 2004 to April, 2005, 23 for May, 2005 to April, 2006, 69 for May, 2006 to April, 2007, and 41 for May, 2007 to April, 2008, The maximum value median of AST, ALT, and bilirubin during admission was 989 IU/L, 1999 IU/L, and 5.6 mg/dL each, Each factors were all positively correlated with the patient's age. Conclusions : Recent decrease in antibody positivity of the hepatitis A virus and subsequent surge of acute hepatitis A is a cause of rising socioeconomic costs. A large scale epidemiologic research on whether HAV vaccination should be made mandatory and health insurance applied seems to be needed. Key words : Hepatitis A, Age, Medical fees, Vaccination

야간응급실로 내원한 급성 치통환자의 질환특성에 관한 임상적 연구

유재하,최병호,민연숙,오민성,이지응 연세대학교 원주의과대학 1999 원주의대논문집 Vol.12 No.1

가축과 실험 동물의 생리자료(7) : 제7장 돼지 The swine

정순동,권해병,양일석,김용근 진주농과대학 1971 진주농과대학 연구논문집 Vol.- No.10