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.

구강악안면 영역의 치성 감염 환자에 대한 세균학적 연구

김일규,윤승환,오성섭,최진호,오남식,김의성,이성호,배수환,강문수 대한악안면성형재건외과학회 2000 Maxillofacial Plastic Reconstructive Surgery Vol.22 No.4

Oral & maxillofacial infections are most commonly odontogenic in origin. Although such infections are usually self-limiting, they may occasionally spread deeply into fascial spaces or planes far from the initial site of involvement. If early diagnosis and appropriate therapy is delayed, complications such as mediastinal extension, retropharyngeal spread and airway obstruction could happen to the patients. For the study of the microbiology, we have retrospectively analysed the oral & maxillofacial infected patients in the Dept. of Oral & Maxillofacial Surgery, In-Ha University Hospital from 1997 September to 2000 April. The results were as follows 1.The male patients were more common than female, with male 61.9% and female 38.1%. 2.Dental originated infections were most common cause with the incidence of 62%. 3.Most common fascial space involved was buccal space 42cases(37.2%) followed by submandibular space 13cases(11.5%), infraorbital space 13cases(11.5%), masseteric space 11cases(9.7%) , periapical abscess 11cases(9.7%) . 4.The causative organisms isolated from the pus culture were Gram Positive Bacterial species, which were 46cases(31.9%) of Streptococcus viridans, 16cases(8.6%) of α and β-hemolytic streptococcus, 4cases(3.1%) of Strep.-group D non enterococci, 7cases(5.1%) of Staphylococcus Coa. Neg., 5cases(3.9%) of Staphylococcus aureus, 3cases(2.3%) of Enterococcus faecalis, 1case(0.8%) of Bacillus species, 1case(0.8%) of Peptostreptococcus, 1case(0.8%) of Clostridium and Gram negative bacterial species, which were 4cases(3.1%) of Acinetobacter baumannii, 2cases(1.6%) of Pseudomonas aeruginosa, 2cases(1.6%) of Burkholderia cepacia, 1case(0.8%) of Neisseria species, 1case(0.8%) of Klebsiella pneumoniae, 1case(0.8%) of Klebsiella oxytoca, 1case(0.8%) of Escherichia coli. 5.In drug sensitivity test, high resistant tendency was found in Penicillin system(Penicillin G 83.3%, Ampicillin 60%) and Aminoglycosides (Gentamycin 50%, Tobramycin 45.5%), but tertiary Cephalosporin system(Cefoperazone 9.1%, Ceftazidime 18.2%), and glycopeptides system (Teicoplanin 0% , Vancomycin 0%) showed lower resistancy.

서울의 Penicillinase Producing Neisseria Gonorrhoeae 발생빈도(1996)

김재홍,황동규,전재홍,김윤석,김중환,김용준,이창균,임동진,김현수,조창근,김경문,박상훈,전우형,김희성,이호정,차명수,김갑형,김형석,김석우,황지환,박병순,권오상,이민수,송기훈,성소영,이인섭,부태성 대한화학요법학회 1999 대한화학요법학회지 Vol.17 No.2

Background : In recent years, gonorrhea has been panedemic and remains one of the most commom STDs in the world, especially in developing countries. Objective & Methods: For the detection of a more effective therapeutic regimen and assessing the prevalence of PPNG, we have been trying to study the patients who have visited the VD Clinic of Choong-Ku Public Health Center in Seoul since 1980 by means of the chromogenic cephalosporin method. Results: In 1996, 139 strains of N. gonorrhoeae were isolated, among which 53(39.0%) were PPNG. Conclusion: Our results suggests that after a peak of 74.3% in 1993, the prevalence of PPNG in Seoul is gradually declining.

軟弱地盤上에 築造된 農業用貯水池 堤體의 壓密擧動

오범환,이달원,임성훈 충남대학교 농업과학연구소 2002 농업과학연구 Vol.29 No.2

본 연구는 연약지반상에 축조되는 농업용 저수지의 압밀거동을 현장계측결과를 기초로 기존의 예측방법등과 비교분석하고, 시공중 또는 완공후에 측방유동등으로 인하여 국부적인 전단파괴 가능성을 현장계측치로부터 정량적으로 파악하여 비교분석한 결과 다음과 같은 결론을 얻었다. 1. 최종 예상침하량으로 추정한 압밀도는 Terzaghi 방법에서는 작게 추정되었고, 편차가 크게 나타나서 오차범위가 작은 Asaoka와 Hyperbolic방법을 기준으로 압밀도를 적용하는 것이 합리적이라고 판단된다. 2. 성토에 의한 점증재하시 과잉간극수압의 소산은 성토시공중의 소산과 최대간극수압 이후의 소산이 합성되어 발생하는 복합적인 거동을 나타냈다. 또한 압밀초기에는 침하량으로 압밀도를 예측하는 것보다 계측자료가 충분한 과잉간극수압을 이용하여 압밀도를 예측하는 것이 신뢰성이 클 것으로 판단된다. 3. 성토완료후 초기에는 시공중 소산된 과잉간극수압(U_(d))을 이용한 압밀도가 최대과잉간극수압을 이용한 압밀도(U_(p))보다 12∼27% 정도 더 크게 나타났고, 침하량으로 추정된 압밀도에 근접하므로 소산된 과잉간극수압에 의하여 압밀도를 추정하는 것이 합리적이라고 판단된다. 4. U_(d)와 U_(p)의 관계식은 주계측 단면에서는 U_(d)=(1.3∼3.6)U_(p), 부계측 단면에서는 U_(d)=(1.2∼1.9)U_(P)로 소산된 과잉간극수압으로 추정된 압밀도가 더 크게 나타났다. 또한 저수지 제체의 안정성을 한계평형법에 의해 분석한 결과 모든 조건에서 기준 안전율보다 커서 안정한 상태로 나타났다. This study was performed to evaluation the consolidation behavior of agricultural reservoir in the very soft ground. The final settlement prediction methods by Terzaghi, Hyperbolic and Asaoka methods were used to compare with the degree of consolidation estimated by exess pore water pressure. The dissipated excess pore water pressure during embankment construction and peak excess pore water pressure on the completed embankment were suggested for the estimation of the degree of consolidation. It was concluded that the degree of consolidation estimated from dissipated excess pore water pressure was more reliable than that from the peak excess pore water pressure. The stability methods for agricultural reservoir was used to compare and analyze with various condition by limit equilibrium method.

P-Toluenesulfonanilide의 공간군 결정

오인근,김창진,서일환,조성일 충남대학교 1985 忠南科學硏究誌 Vol.12 No.2

The space group os p-toluenesulfonanlide, C_13 H_13 NO_2S, has been determined by single crystal X-ray photographic data collected three-dimensionally using Weissenberg and precession methods with Cu Kα radiation (λ=1.5418 Å). The crystal data are monoclinic, space group p 1 2_1/n 1 with cell dimensions a=15.369±0.423Å, b=9.806±0.009Å, c=8.99±0.03Å, β=98.53±0.18°and z=4. The precise a and b parameters were obtained by finding a proper extrapolation function and using the least-squares refinement of eight 2θ values measured on (hk0) and (h0ℓ) Weissenberg photographs, and because of insufficient number of diffraction-spots along the c^* axis the c parameter and the β angle were measured from oscillation and Weissenberg photographs respectively. Four molecules in a unit cell appear to be related by screw diads parallel to the b axis and n-glide planes perpendicular to it.

브러쉬리스 직류전동기의 정상상태 해석

오성보,김일환 제주대학교 1991 논문집 Vol.32 No.-

120。 도통 전압원 인버터로 역기전력이 제형파인 브러쉬리스 직류전동기를 정상상태로 운전할 때 수학적 해석과 컴퓨터 시뮬레이션 및 실험에 의한 결과를 고찰하였고 다음과 같은 결과를 얻었다. (1) 절환각의 변화에 따라 주파수 대 전류각 특성과 전류각 Θ??를 결정하여 준다. (2) 주파수 증가에 따라 전류와 역기전력의 위상이 변하여 토오크 특성에 영향을 주고, 주파수에 따른 절환각을 제어하여야 출력 토오크특성을 향샹시킬 수 있다. (3) 제안한 해석방법을 이용하면 120。 도통 전압원 인버터 시스템을 설계할 때 유용하다. In this paper, the steady-state performance of brushless dc motor which has the trapezoidal counter emf driven by a 120。 conduction voltage inverter is investgated. The commutation angle is operated by the system parameter in commutation period. As the frequency increasing, counter emfis growing and it varys the phase and amplitude of current, and torque characteristics. The commuatation angle vs operating frequensy is calculated, and torque characteristics controlled by the advanced commutation angle are verified by the computer simulation and experiment.

상악골 전벽골 겸손에 대한 재건술에 있어서 동결건조 콜라겐 매식과 소강판고정술의 임상적 유용성

오승환,장관식,조병호,민승기,이동근,김수남 대한악안면성형재건외과학회 2000 Maxillofacial Plastic Reconstructive Surgery Vol.22 No.6

Maxilla is located in midfacial area and has intimate relationship with adjacent anatomical structure such as nasal cavity, orbit, oral cavity, and zygoma. Skeletal defects of maxillary antral wall may be developed by various postoperative causes for comminuted maxillary fractures, tumors of head and neck area or cystic lesions of maxillary sinuses. If these bony defects are left untreated state, this results in several postoperative complications such as soft tissue impingement into bony defects or dysfunction of sinus mucosa. Hence, these defects should be pertinently treated as possible. The main purpose of such surgery is to preservation of normal physiologic function of maxillary sinus. In the past, a variety of materials have been used to reconstruct defects of the maxillary antral wall. Alloplastic materials are popular today because of availability without an additional operation and their ease of use. With favorable results and review of related literatures, we report the availability of lyophilized collagen implantation and microplate fixation as the reconstructive surgical methods on the defects of maxillary anterior wall resulted from various reasons.

SC 합성 기둥-철골 보 접합부의 내진성능에 관한 실험적 연구

오명호,이창환,김명한,김대중,김상대 대한건축학회 2005 大韓建築學會論文集 : 構造系 Vol.21 No.3

Steel-concrete composite column is a recently developed composite system, in which the two opposite flanges of H-shape section are connected by welded links, and vacant space enclosed by the flanges, web and links is filled with concrete. The purposes of this paper are to suggest efficient moment-connection details for SC composite column system and to verify their seismic performance. Two types of SC composite column-steel beam connections were proposed; one for strong axis of column and the other for weak axis of column. Cyclic loading tests for two full-scaled specimens were performed according to the standard loading history of SAC(2000). Moment-connection detail for strong axis of column showed sufficient seismic performance required for SMRF(special moment resisting frame). However, connection detail for weak axis of column exhibited inferior seismic performance than that for strong axis of column, which satisfied the requirements for OMRF(ordinary moment resisting frame). Additional studies are needed to increase elastic stiffness and seismic performance of connection detail for weak axis of SC composite column.

機械加工品의 最適加工速度에 關한 硏究

成煥泰,吳澤烈,吳煥燮 慶熙大學校 1980 論文集 Vol.10 No.-

In this study, the optimum mathematical models were made in order to derive Optimum Machining speed which is due to be established in the production of each manufactures as an important parameter based upon the cutting speed, in case of making manufactures of multi-kinds into unit-production processing. The economical optimum cutting speed has been set up by using the above phenomenon as a proper system, and the results from the comparative analysis between the above model & the actual cutting work data, are summarized as follows. (1) The mathematical models for the optimum machining speed are derived into the expressions (23), (24), (25), (26), (27), (28), (29). (2) The basic expressions of the optimum machining speed are derived into (32), (34), (36), (37), (39), (40), (41), (44), for the purpose of each estimation of the maximum efficiency standard, the minimum cost standard and the maximum profits rate standard. (3) The example of setting up the optimum cutting speed of multi-kinds manufacturing production was formulated, and the experimental theoretical values were known to be in the same range as a result of the comparative study between the cutting speed obtained by the cutting test & the optimum cutting speed calculated by the theoretical expressions.

둔상에 의한 간 손상 환자의 CT분류에 따른 치료결정

오성환,김갑득,송화식 대한응급의학회 2001 대한응급의학회지 Vol.12 No.4

Background: Because of increased number of traffic and industrial accidents, the incidence of blunt abdominal injury patients has increased. Recently, abdominal computed tomographic(CT) scans have been widely used in emergency departments for initial diagnostic workups on patients with blunt hepatic injuries. The purpose of this study is to analyze the correlation between abdominal CT scans and the clinical outcomes and to recommend a direction for the management of blunt hepatic injury. Methods: A retrospective review was conducted of 66 patients with blunt hepatic injuries who underwent abdominal CT scans and were treated at the Department of Emergency Medicine of Dankook University Hospital during the period from January 1998 to December 2000. Statistical analysis was performed using the chi-square(χ2) test, Spearman correlation test, Cochran-Mantel-Haenszel chi-square(χ2) test and Fisher's exact test; a value of p<0.05 was considered significant. Results: Based on CT scans, we graded the liver injuries by using the system of the Organ Injury Scaling Committee of American Association for the Surgery of Trauma, Grade II injuries(28 cases, 42.4%) were the most common in this study. Most patients with injuries above grade III were managed surgically, and CT grades correlated well with operative treatment and initial fluid resuscitation. Initial shock status correlated with the CT grade, but did not correlate with operative management. For non-operative management, as the CT grade increased, the amount of blood transfusion also increased. Increasing liver enzyme did not correlate with CT grade. The mortality rate was 9.1%, and the most common cause of death were hypovolemic shock due to massive bleeding. Conclusion: Non-operative management is the first choice of treatment in low grade blunt hepatic injury(CT grade I, II, and III). For cases above grade IV hepatic injury, the key points of operative management were the hepatic injury itself and it's complication.