성장기 아동의 single tooth scissors bite의 교정 치료: 증례 보고

김지인,현홍근,김영재,김정욱,장기택,이상훈,한세현,김종철 大韓小兒齒科學會 2011 大韓小兒齒科學會誌 Vol.38 No.4

A scissors bite in the posterior teeth occurs when the upper teeth are positioned totally buccal to the lower teeth in centric occlusion, either unilaterally or bilaterally. This malocclusion can result from either excessive width of the maxilla or deficient width of the mandible, or sometimes combination of the both. Scissors bite, when left untreated without a proper dental intervention, interferes with the normal mandibular growth leading to a state where consequent disharmony in dental arch width evokes occlusal disturbances. Therefore, early preventive orthodontic treatment is necessary in patients with scissors bite. Scissors bite rarely involves anterior and posterior sites concuttently across the dental arch but usually affect single tooth. Even in the single tooth scissors bite cases, more likely to be met in the clinical fields, immediate dental intervention is indicated because continuous occlusal forces that exacerbate the already adverse axis of the posterior teeth. In this case study, patients with single tooth scissors bite, each 7, 14, 12, and 16 years old, were each treated with criss-cross elastic, fixed appliance, removable appliance, and miniscrews. With the proper selection of appliances appropriate to each specific cases, good treatment outcome can be achieved without resulting any side effects. 중심교합위의 상태에서 편측 혹은 양측으로 상악 구치부의 치아가 하악 구치부의 협측으로 위치한 경우를 scissors bite라 고 한다. 이는 상악의 폭경이 크거나 하악의 폭경이 좁은 경우 발생한다. Scissors bite의 경우 방치하게 되면 하악의 성장이 방해받게 되고 그 결과, 악궁 폭경의 부조화가 심해져 저작 장애를 일으킬 수 있으므로 조기 차단 교정이 반드시 필요하다. 실제 임상에서는 여러 치아의 scissors bite보다 최후방 구치 혹은 그 외 하나의 구치만의 single tooth scissors bite(STSB)을 보이는 경우가 많다. 이러한 STSB의 경우도 방치하게 되면 저작력으로 인하여 구치의 각도가 더욱 악화되므로 즉각적인 치료가 필요하다. 본 증례에서는 STSB를 보이는 7세, 14세, 12세, 16세의 환자에게 각각 criss-cross elastic, 고정성 장치, 가철성 장치, miniscrew를 사용하여 치료한 증례를 보고하였다. 각 환자의 증례에 적합한 장치를 잘 선택하여 사용한다면 치아를 정출시키는 등의 부작용을 야기하지 않고 양호한 결과를 얻을 수 있을 것이다

PC,SAN,ABS,PB 및 LDPE의 온도에 따른 점도변화에 관한 연구

김종엽,맹기석,전종한 忠南大學校 産業技術硏究所 1987 산업기술연구논문집 Vol.2 No.2

In this research, viscosities of six different polymers were experimentally measured with a rotating disc type rheometer. The tested polymers include polycarbonate(PC), styrene acrylonitrile copolymer(SAN), low density polythylene(LDPE), polybutadiene(PB) and two acrylonitrile-butadienestyrene copolymers(ABS-1 and ABS-2). Buche's theory on viscosity-temperature relationship was found to be applicable to the polymers for a wide range of shear rate from 1 to 100/sec. The activation energy E* for the flow decreased in the oder of PC, SAN, LDPE and PB. The order was attributed to the chemical structures of the polymers. It was also found that as the shear rate increased, E* tended to decrease. This is due to the fact that the high shearing energy could be transferred to polymer segments.

남제주군 육상 양식장에서의 소수력 발전시스템의 적용성

김도진,김태한,좌종근 제주대학교 공과대학 첨단기술연구소 2004 尖端技術硏究所論文集 Vol.15 No.1

The applicability of a small hydro-power system for water pollution treatment facilities is investigated at the fish farm in Nam Jeju. For this study, the present situations of the fish farm are examined, and the running problem of screen is found out. As a means of solving this, the small hydro-power system which runs with seawater of head tank is considered. In order to apply this system, the field examination is carried out by sampling methods. The flux and the gross head are measured from selected site at the fish farm, and available generating electric power is estimated by these data. From this result, it is turned out that there is a set up possibility of this system at the fish farm.

가토에서 일측 요관 부분 및 완전폐색시 신장과 요관의 조직학적 변화

김상현,김용웅,육승모,한동석,노안식,임재성,김홍식,나용길,설종구 충남대학교 의학연구소 2003 충남의대잡지 Vol.30 No.2

This study was designed to clarify histologic changes in the experimental rabbit kidney and ureter after unilateral partial or complete ureteral obstruction. A total of 20 adult white rabbits were divided into 4 subgroups in the partial obstruction followed by 2 weeks, the partial obstruction followed by 4 weeks, the complete obstruction followed by 2 weeks, and the complete obstruction followed by 4 weeks. The normal control group was consisted of 5 adult white rabbits. The kidneys and ureters for light microscopy were fixed in 10% neutral formalin, embedded in paraffin and stained with hematoxylin and eosin. Abnormal histologic fingings showed in ipsilateral kidney and ureter of all subgroups(such as dilatation of uriniferous tubule, focal necrosis and desquamation of epithelium, interstitial fibrosis, glomerular congestion, widening of Bowman's space, dilatation of ureter, epithelial cell atrophy or loss, interstitial fibrosis and interstitial inflammation). These findings were most severe in the group of the complete-obstructed ureter for 4 weeks. No significant changes showed in contralateral ureter of all subgroups. The degree of obstruction was severe and period of obstruction was long, the histological changes in ipsilateral side were severe. Despite of changes in ipsilateral side no abnormal findings showed in contralateral side. We suggest that long term experimental investigation of histologic changes in ipsilateral side and compensatory changes in contralateral side have to be studied.

광양만의 저질 중금속 농도 분포 특성

김도희,유한홍,정종성,조현서,신현출 木浦海洋大學校 2002 論文集 Vol.10 No.1

The main goals of the study were to investigate the sediment quality and trace metal distribution in sediment of Kwangyang Bay, south coastal of Korea. Surface sediment sampling were performed in November, 2000 and February and March, 2001. The concentration of H₂S, IL and COD in sediment were measured by a manual of the Department of Marine Environment of Korea. The extracted trace metals Fe, Cu, Cd, Pb, and Zn in sediments mean analyzed by the flame atomic absorption spectrophotometer with an instrument of model Shimadzu AA-6701F. H₂S, IL and COD in the surface sediment were 1.3 mg/g, 5.9 % and 15.0 mg/g, respectively. The mean content of Fe, Cu, Cd, Pb and Zn were 1523 mg/kg, 4.799 mg/kg, 1.321 mg/kg 9.285 mg/kg and 9.353 mg/kg, respectively. All of these measured trace metals level were over the other reported trace metal level in sediment of coastal area. According to histograms, the content of H₂S, IL and COD and trace metals in sediment of this study were affected by artificial activities rather than natural process.

기체-고체 유동상에서 고체입자의 혼합특성에 관한 실험적 연구

金鍾億,陰漢龍,金聖九 弘益大學校 科學技術硏究所 1997 科學技術硏究論文集 Vol.8 No.-

In the present study, mixing characteristics of solid particles in bubbling fluidized bed have been analyzed in a freely bubbling two-dimensional bed experimentally. Verticall and horizental particles mixing was studied by using heated particles as tracers. The steady-state temperature patterns around a heated wire and transient response to an injected pulse of heated particles were measured. A qualitative study of bubble size, velocity and void fraction in the two -dimensional bed was made by using a high-speed viedo recorder. Through the screen anlaysis of bubble flow it was verified that the size of bubbles increases with the rise of excesive velocity or bed height. Steady state experitments gave the result that the movement of heated particles in beds was more vigorous in higher excessive velocity. In trasient experimet the higher excesive velocity delay time of high temperature particles injected into the bed were the shorter. Dispersion coefficient was found to be increased with grouth of the bubble size and excessive velocity.

구륜 이동 로봇의 위치추정을 위한 퍼지-유전자 제어기

한철웅,김종수,류평,오금곤,박세승 조선대학교 전자정보통신연구소 2000 電子情報通信硏究所論文誌 Vol.3 No.1

지능제어 기법중 하나인 퍼지-유전자 알고리즘은 매개변수 불확실성을 갖는 시스템을 제어하기 위한 새로운 제어 기법으로 사용되어지고 있다. 유전자 알고리즘에서, 돌연변이율은 국부적 최소화에 수렴하는 것을 방지하기 위하여 크게 설정하여야만 하지만, 전역 수렴 속도가 감소하는 문제점을 가지고 있다. 이러한 문제점을 개선하기 위하여 퍼지 논리와 유전자 알고리즘을 사용하여 제어기를 설계한다. 본 논문에서는 구륜이동 로봇의 목적궤적을 추적할 수 있는 제어기 설계를 제안한다. 제안된 제어기의 유용성은 모의실험을 통하여 보인다. Genetic algorithms, one of intelligent control methods, is used as new control approach to control the system including the parameter uncertainties In the genetic algorithm, the mutation rate must be set to high to prevent the convergence to local minimum, but it has the problem that the global convergence speed is decreased To enhance this problem, we design the controller by using the fuzzy logic and the genetic algorithm In this paper, we propose the controller design to track to the desired trajectory of the wheeled-mobile robot The validity of the proposed controller is showed through the simulation.

미맹출 유규치에 관한 증례

한연선,최병재,김성오,이종갑 大韓小兒齒科學會 2002 大韓小兒齒科學會誌 Vol.29 No.3

치아의 맹출은 치아가 구강내 교합평면에 도달하여 기능적인 위치를 차지할 때까지의 치아 이동 및 골조직 내에서의 발달로 이루어지는 생리학적인 양상으로 이해되어진다. 그러나 치아가 정상적으로 맹출해야 하는 시기를 지나서도 골조직 내에서 맹출하지 않을 수 있으며, 이러한 치아를 매복치라 일컫는다. 이러한 치아 매복의 주된 요인은 국소적인 것으로 악궁내 공간부족, 치아 위치 이상, 과잉치, 맹출 경로의 감염, 낭종 및 안면 외상으로 인한 치배의 영향 등이 있다. 또한 쇄골두개이골증, 골다공증 등의 전신적 그리고 유전적 질환도 맹출 장애와 맹출 지연 등과 관련이 있다. 현재까지 매복치의 대부분은 영구치로 보고되었으며 반면에 유치의 매복에 대한 것은 극히 소수에 불과하고, 매복된 유치의 대다수는 제 2 유구치이다. 유치의 매복은 유착에 의해 이차적으로 생긴 저위교합과는 구별되어야 하며, 유치의 매복에 대한 병인은 유치 치배의 비정상적인 발달로 인해 조기에 유착이 일어나는 것으로 추측되어지고 있으나, 아직까지 정확하게 밝혀진 바는 없다. 유치의 맹출 실패로 나타날 수 있는 문제점으로는 계승 영구치 발달 및 맹출 방해, 낭종 형성이나 감염의 발생 등을 생각해볼 수 있다. 본 증례들은 연세대학교 치과대학병원 소아치과에 내원한 환아의 구강 및 방사선학적 검사에서 유구치의 매복이 관찰되었기에 이에 보고하는 바이다. The term 'impaction' is used to designate a tooth which remains unerupted in the jaw beyond the time at which it should normally be erupted. The main causal factors are local (lack of space, ectopic positions of teeth, supernumerary teeth, cyst, the occurrence of infectious process in the eruption path, traumatic facial injury etc.). Systemic and genetic disorder, however, may have primary failure of eruption and retarded eruption as additional symptoms (cleidocranial dysplasia, osteopetrosis etc.). Most cases of impacted teeth reported in the literature are of permanent teeth. The absence of primary teeth occur rarely whereas impaction of second primary molars is more numerous than all other impactions. Impaction due to primary failure of eruption must be distinguished from the secondary infraocclusion. The eti-ology of impaction of primary teeth is probably related to early ankylosis of primary teeth, but it is not clear. Failure of eruption of primary teeth cause a number of complications, such as interference with develop-ment and eruption of succedaneous teeth, formation of cyst, and damage to adjacent teeth. This study is to report cases of primary failure of eruption in the primary dentition.

습관성 흡연여성에서 후측 수부에 발생한 Buerger씨병

김삼,이남호,육청미,최영진,백대균,홍경순,두영철,한규록,오동진,유규형,임종윤,이광학,이영 대한순환기학회 2000 Korean Circulation Journal Vol.30 No.7

이하선 타액내 Parotid Isoelectric Focusing Variant Protein (PIF)의유전적 다형선상에 관한 연구

한동호,김종열 大韓法醫學會 1993 대한법의학회지 Vol.17 No.2

In order to identify the polymorphism of the parotid isoelectric focusing variant protein(PIF), as an integrating part of systemic study about proteins, this study was conducted. One-hundred and fifty healthy adult Koreans between the ages of 20 and 29 were chosen, and their parotid saliva was collected. The parotid asliva went under isoelectric focusing on a urea-plyacrylamide slab gel(pH 3.5-5.2) for 5 hours. Then, it was stained with Coomasie Brilliant Blue R-250/20% Trichloroacetic acid (TCA) and again was destained with 20% TCA solution. The phenotype frequency and gene frequency of each isoelectric focusing variant protein(PIF) were obtained, and the subjects were divied into the indigenous family name froup and immigrated family name group. The phenotype and gene frequency of each group were compared, and the following results were obtained : 1. The phenotypes of parotid isoelectric focusing variant protein(PIF) observed in paroted saliva of the 150 koreans were PIF(+) in 140 people(93.3%) and PIF(-) in 10 people (6.7%). 2. The gene frequency of PIF?? was 0.742, and that of PIF?? was 0.258. 3. Of the 150 Koreans, the gene frequencies of the indigenous family name group were 0.733 in PIF?? and 0.267 in PIF??; those of the immigrated family name group were 0.796 and 0.234. 4. The gene frequency of the entire Korean group was closer to that of indigenous family name gorup than the immigrated family name group.