The prediction of the tooth size in the mixed dentition for Korean

Moon, Sung-Hwan,Kim, Seong-Oh,Yu, Hyung-Seong,Choi, Byung-Jai,Choi, Hyung-Jun,Lee, Jae-Ho 大韓小兒齒科學會 2006 大韓小兒齒科學會誌 Vol.33 No.2

이번 연구의 목적은 혼합치열기 아동에서 미맹출된 견치와 소구치의 크기를 예측하는데 있어서 한국인에 맞는 방정식을 만들기 위함이다. 미맹출 치아의 크기를 예측하는 것은 혼합치열기 교정 진단과 치료계획 수립에 있어서 매우 중요하다. 미맹출된 견치와 소구치 크기를 예측하는 방법은 몇가지가 있지만 그중에서도 가장 흔하게 쓰이는 것이 모이어의 예측표와 다나카와 존스턴의 방정식이 있다. 하지만 그것들은 백인을 위해서 제작된 것이고 치아 크기는 인종에 따라서 다르다고 알려져 있다. 이번 연구에서는 치아크기를 측정하여 하악 영구 절치의 크기 합과 견치 및 소구치의 크기 합 사이의 상관관계를 구하고 회귀방정식을 이용해서 한국인에 맞는 예측표를 만들었다. 연세대학교 치과대학에 재학중인 178명의 한국 학생(남 108명, 여 70명, 평균연령 21.63)을 대상으로 실험하였다. 영구치의 근원심 폭경을 석고모형상에서 calipers를 이용해서 측정하였다. 성별간의 치아 크기는 차이가 있었다(p<0.05). Correlation coefficient는 0.57에서 0.64의 범위였고, standard errors of the estimates 는 여성에서 0.6으로써 남성보다 우수하였다. r^(2)값은 0.27에서 0.41의 범위를 나타내었다. Estimating the size of unerupted teeth is an essential aspect of orthodontic diagnosis and treatment planning in the mixed dentition. Several methods were introduced and used for the prediction. The most common methods among these would be Moyers probability chart and Tanaka and Johnston equations. These are currently used widely, but they were developed for Caucasians. Because there are clear racial differences in teeth size, the objectives of this study were to produce correlation coefficients between the combined mesiodistal widths of the permanent mandibular incisors and those of the canines and premolars for each quadrant, and prediction tables with regression equations, specifically for Korean. 178 young adults (70 women, 108 men, mean age 21.63 years) were selected from the College of Dentistry, Yonsei University, Seoul, Korea. The mesiodistal crown diameters of the permanent teeth were measured with calipers. Significant sexual dimorphism was found in tooth sizes. The correlation coefficients between the total mesiodistal width of the mandibular permanent incisors and those of the maxillary and mandibular canines and premolars were found to be between 0.52 and 0.64. The standard error of the estimatation was better (0.60) for women and the r^(2) values ranged from 0.27 to 0.41 for both sexes, Prediction tables were prepared for Korean. This study showed larger canine and premolar diameters than Tanaka and Johnston's and Moyers' studies which might be due to the racial differences. Further investigations with a larger sample size will be needed for more representative data on the Korean population.

Hg₁-xMnxTe산화막의 홀효과에 관한 연구

오재근,최기영,송재흥,김영국,채건식,주유환,설정식,손인호,차성극,이상찬 慶南大學校 附設 基礎科學硏究所 1996 硏究論文集 Vol.8 No.-

HClO₄(pH:2) 수용액에서 양극산화 방법으로 HgMnTe(HMT)의 표면에 산화막을 형성 시켰다. 산화막의 두께는 SEM으로 측정하였으며 10㎛였다. 전류-전압 특성곡선을 얻어 산화 피크 전압으로부터 HTeO₂?, TeO?, HHgO₂? 막이 형성되었음을 알 수 있었다. 산화시키지 않은 HMT와 HClO₄수용액에서 산화시킨 HMT에 대해 Hall전압 및 자기저항을 각각 측정하였다. 홀전압과 자기저항은 HMT보다 HMT산화막에서 더 컸으며 이것은 HHgO₂? 공격자가 홀의 역할을 하고, TeO₄? 산화막은 전하의 포획도를 낮게하기 때문으로 생각할 수 있다. Anodic oxidation processes on HgMnTe surface has been studied in standard aqueous HClO₄(pH:2) solution. The 10㎛ thickness of the anodic oxide layers was measured by SEM. The Composition of the anodic oxide layers are evaluated from current-voltage(I-V) characteristic of HgMnTe Oxidation. The layers are composed of mixed oxide. ??, TeO₄, and?? in HClO₄solution. Transport properties have been investigated in HMT oxide layer made in HClO₄solution and virgin HMT samples at 300K. Hall voltage and magnetoresistance are greater in oxide layer HMT than virgin HMT. As a result, we know that the vacancy of ??in an anodic oxide layer acts as hole and the resulting oxide ?? layer exhibit a reduced degree of charge trapping and increase magnetoresistance.

採卵養鷄農家의 經營分析 : 1976年을 中心으로

吳聖煥 건국대학교 1979 論文集 Vol.9 No.1

① The average amount of investment of feeding 100 laying hens per farm amounted 381,945 Won of whick 93.7 percent is defts and 6.3 percent owned capital. ② The amount of feeds per 100 laying hens was 4,607 kg. The result of the study evidenced that the amount of feeds gradually decreases as the size of feeding increases. ③ The laying rate of eggs was 66.7 percent. The feeding size of 5,000~8,000 heads showed the highest laying rate of eggs which is equivalent to 71.8 percent. ④ The average raising costs of hens amounted to 1,390 Won of which 66.6 percent was feed costs indicating the highest cost item. ⑤ The production cost per 10 hens summed to 230.66 Won on average, Farmer's price pre 10 eggs was 243.57 Won. The size of feeding more than 5,000 hens could make net profit. ⑥ The production cost is consisted of 71.4 percent of feeds, 11.9 percent of the depreciation for hens, 6.7 percent of labor, 44 percent of owned labor, 1.5 percent depreciations for buildings and equipments, and 1.2 percent of medications. ⑦ Gross recepts per farm totaled to 25,274,000 Won of which 97.8 percent was from laying eggs and 2.2 percent from by-products. ⑧ The average operational costs per farm totaled to 22,151,400 Won of which the biggest cost item was feed costs showing 77.3 percent. ⑨ Average income per farm amounted to 3,122,700 Won. The total amount of income per 100 laying eggs summed to 76,400 Won. As the size of feeding increases the income gradually decreases. ⑩ Average profit per farm was made by farms feeding more than 5,000 hens. Therefore, being the commercial operation the sure of feeding should be, at least, more than 5,000 laying hens. ⑪ Profit per 100 laying hens amounted to 32,260 Won. The highest profit, which is equivalent to 92,260 Won, was associated with the feeding size of 5,000-8,000 laying hens, while the size less than 5,000 laying hens made a defict summing to 6,600 Won. ⑫ Average returns for labor per 10 labor hours summed to 2,638 Won and the annual rate of refutns on the total investment was equal to 22.3 percent which considered very high.

기관골 신생증 1예

오영상,이은우,정종혁,문승원,김수현,김동한,양혁승,박정환,박경옥,강성수,이영직 朝鮮大學校 附設 醫學硏究所 2006 The Medical Journal of Chosun University Vol.31 No.2

Tracheobronchopathia osteoplastica is a rare disorder of unknown cause characterized by the projection of numerous bony or cartilaginous submucosal nodules into the tracheobronchial lumen with sparing of the posterior membranous portion of tracheobronchial tree. In the past, most of the cases were diagnosed as secondary finding at autopsy. Nowaday, the key component of the evaluation is flexible fiberoptic laryngoscopy and bronchoscopy, which typically demonstrates irregular spicules of subrnucosal bone and cartilage projecting into the tracheobronchial lumen and causing various degrees of airway obstruction. A 45 years old man was visited Sunchon St. Carollo hospital due to discomfort on throat. We saw several nodules just below vocal cord via laryngoscope. The computed tomography revealed multiple small calcified nqdules on trachea and both main bronchi. Pathologic finding of bronchoscopic biopsy showed abnormal proliferation of bony and cartilagious nodules in the tracheal submucosa. These fingdings were consistent with tracheobronchopathia osteoplastica. We report here on a case of tracheobronchopathia osteoplastica with review of literature.

이종재 브레이징 계면에서의 균열거동 해석

오환섭,김시현,김성재,양인수 한국공작기계학회 2002 한국생산제조학회지 Vol.11 No.6

Applications of brazing in the studying fields such as high-speed machining are very increasing in various industry fields. Therefore, applying to the fracture mechanics by numerical analysis method is very important to analyse the crack problem dissimilar materials in brazed interface. In this study, stress intensity factor(SIF) is analysed to investigate crack behavior on the crack tip of dissimilar materials in brazed interface such as a hardmetal and a HSS by two dimensional(2-D) BEM. Kelvin's solution was used as a fundamental solution in BEM analysis and stress extrapolation method was used to determine SIF.

Crawford Ⅲ형과 Ⅳ형 흉복부 대동맥류 4예 보고

문성민,손민수,이길연,이상목,고석환,홍성화,윤충,오수명,박호철 대한혈관외과학회 2003 Vascular Specialist International Vol.19 No.2

蹴球競技의 Running Jump Heading에 관한 動作分析

洪盛杓,吳延煥 忠南大學校體育科學硏究所 1987 體育科學硏究誌 Vol.5 No.1

The consequence of experiment gained to make an offer reference materials about scientific posture guidance and reform of jump heading in soccer is following. 1. When you practice jump heading, the velocity of every joints is very different. That is, that of the head joings is most rapid of all the joints. And the sequence of the velocity of every ones is ancle, knee, hips joints. 2. In order that you practice successful jump heading your neck joints velocity must be more rapid than any other’s. And your other joint, for example, knee, ancle, hips joint, their velocity must be as slow as you can. 3. You have to hit a ball before your jumping body is most high point from the bottom if you practice successful jump heading. 4. In order to show your powerful jump heading the angular velocity of your head must be as fast as you can. 5. When you practice jump heading, no matter which your feet can be used, there is no problem. 6. When you practice jump heading, if your femoral muscle can be constructed, your heading will be faster. 7. When you take off, your energy works to vertical direction.

교면 덧씌우기 콘크리트의 引拔附着强度 試驗法 提案

김성환,김동호,김현오,이봉학 강원대학교 산업기술연구소 2003 産業技術硏究 Vol.23 No.A

The development and maintenance of a sound bond are essential requirements of concrete repair and replacement The bond property of a overlay to its substrate concrete during the lifetime is one of the most important performance requirements which should be quantified A standard or a verified bond strength measurement method is required at field for screening. selecting materials and quality control for overlay or repair materials. but no test method has been adopted as a standard. In this study. a concrete pull off bond strength measurement method for field application is proposed and evaluated. This study compares the splitting tensile test. slant shear test. nipple pipe direct tensile test. flexural adhesion test. briquette tensile test. jumbo nail pull-out test and core pull-off test with their test procedures. From these cornpanson and investigation. core pull-off test is selected as a main topic of this study because of it's suitability for in situ testing. simplicities in field application and clearness at interface boundary condition Thus. the proposed core pull off test is evaluated to be the most appropriate method for field application in a simple manner. The fracture surface and fracture mode could be easily determined by visual observation of failure surface of the field specimen. The core pull off test was found to be sensitive to surface condition and latex contents at latex modified concrete

PTFE 이식편을 이용한 대퇴동맥과 슬관절이하 동맥 우회로술의 결과 분석

문성민,손민수,이길연,이상목,고석환,홍성화,윤충,오수명,박호철 대한혈관외과학회 2004 Vascular Specialist International Vol.20 No.1

CMP 폐액의 고액분리에서 응집제의 영향에 관한 연구

홍성호,오석환 대한상하수도학회 2002 상하수도학회지 Vol.16 No.2

A coagulation was applied to separate the solid and liquid from waste CMP generated from the CMP process. Three different coagulants - PACl, MgCl_2 and Ca(OH)^2 was used to find the best coagulant and optimum condition of each coagulant for water and solid recovery. When the solid content was 0.lwt%, the adequate flocculation speed was 10 to 30 rpm for PACl. However, the flocculation speed was not critical for MgCl_2 and Ca(OH)_2 at any dosage. Minimum sedimentation time was 30 minutes to get less than 1NTU of turbidity, the sludge volume was 10 to 15% and 50 to 55% for 0.1wt% and 0.5wt% of waste CMP slurry, respectively. According to the experimental results such as turbidity, zeta potential and heavy metal concentration in the supernatant PACl was the best coagulant for water recovery.