• Imaging Science in Dentistry
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• 제33권3호
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• pp.131-135
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• 2003

Purpose: To determine whether the mandibular radiomorphometric indices in panoramic radiography are correlated with the bone mineral density of Cu-equivalent images in intraoral film. Materials and Methods: The bone mineral density (BMD) of the mandibular premolar area was measured in the Cu-equivalent image of intraoral film. The Panoramic Mandibular Index (PMI) and Mandibular Cortical Width (MCW) were measured in panoramic radiographs of six dry mandibles, and the Pearson correlation between PMI, MCW, and BMD were tested. Results: There were no significant correlations between PMI and BMD (r = 0.280), nor between MCW and BMD (r =0.237). Conclusion: The results show that PMI and MCW were poor diagnostic indicators of mandibular BMD in the six dry mandibles used in this study. The correlationship between the mandibular radiomorphometric indices (PMI and MCW) and mandibular BMD needs to be researched further using large in vivo patient samples.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1999년도 Proceedings of International Symposium on Remote Sensing
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• pp.249-255
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• 1999

Water pollution is becoming a serious problem in the populous cities and coastal areas near industrial complex. Sometimes, phytoplankton is considered as the most important element in the coastal environment. Phytoplankton is easily estimated by measuring chlorophyll content in the laboratory. In this study, to build up estimating algorithm of the chlorophyll amount related to the monitoring of coastal environments in Kwangyang bay, the correlationship the respective in situ observed data with Landsat TM and SeaWiFS satellite Image was analyzed. It showed that Landsat TM band 3 image has the highest correlationship with observed data, and based upon this result the monitoring algorithm of chlorophyll in coastal area was extracted. This algorithm will be an important for extracting and controlling environment elements in coastal areas in the future. And it has a significant meaning that it has established a spatial data construction in which satellite image alone could monitor the coastal environment.

• 한국환경과학회지
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• 제7권2호
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• pp.165-170
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• 1998

The purpose of thins study was to investigate the pollutions of water Qualities in 30 water samples from Nakdong River Western Nakdong River, and Suyoung Stream. COB, BOD. T-N and negative ion(F, Cl+, NO3-, SO42-) of water samples were analysed and the correlationships between water qualities were examined. The mean concentrations of COD(20.26ppm), BOD(25.36ppm), and T-N(18.05ppm) were the highest in the water sample of Suyoung Stream among the three streams and those of F-(0.25ppm), Cl+(2770ppm), and SO42-(37.66ppm) In Western Nakdong River, that of NO3-(10.8 ppm) in Nakdong River. The water quality of Suyoung Stream was the worst among the three streams in hsn area. The correlationships between water qualities were as follows , BOD and COD showed very high correlationship(correlation cofficient, r=0.97),50,2- and NO3'did high one(0.75), and NOa'and COD, BOD did relatively high ones(0.56 and 0.48, respectively).

• Structural Engineering and Mechanics
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• 제72권5호
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• pp.541-555
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• 2019

Wind induced dynamic responses on hyperbolic cooling tower (HCT) shells are complicated functions of structure and wind properties, such as the fundamental frequency f_min, damping ratio ζ, wind velocity V, correlationship in meridian direction and so on, but comprehensions on the sensitivities of the dynamic responses to these four factors are still limited and disagree from each other. Following the dynamic calculation in time domain, features of dynamic effects were elaborated, focusing on the background and resonant components σ_B and σ_R, and their contributions to the total rms value σ_T. The σ_R is always less than σ_B when only the maximum σ_T along latitude is concerned and the contribution of σ_R to σ_T varies with responses and locations, but the σ_R couldn't be neglected for structural design. Then, parameters of the above four factors were artificially adjusted respectively and their influences on the gust responses were illustrated. The relationships of σ_R and the former three factors were expressed by fitted equations which shows certain differences from the existing equations. Moreover, a new strategy for wind tunnel tests aiming at surface pressures and the following dynamic calculations, which demands less experiment equipment, was proposed according to the influence from meridian correlationship.

• 대한치과교정학회지
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• 제21권1호
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• pp.131-170
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• 1991

This study was designed to analyze morphological characteristics of Korean young adults, norms and standard deviation of variables, sexual differences, correlationship between each area of face and correlationship between hard tissue and soft tissue. The primary sample consisted of 45 males and 57 females who were early and middle twenties and had acceptable profile, no history of previous orthodontic treatment, absence of remarkably large overjet and overbite, full complement of permanent teeth, Class I skeletal and dental relationships and good vertical facial proportions. Their cephalograms were analyzed morphologically with a computer morphometrics. Then the final sample - 25 males and 38 females - were selected within 1 S.D. of E-line, ANB, P/A facial height ratio, Interincisal angle, L1 to A-Pog, ODI and APDI. The results of the study were as follows: 1 In the form and proportion of facial skeleton there were no significant differences between males and females, but in the size males were larger than females. 2. The dental protrusion patterns had no significant sexual difference and no significant correlationship between protrusion of upper lip and inclination of upper incisor. But mentolabial angle had positively correlated with interincisal angle and negatively with inclination of upper and lower incisor. 3. In the relationship between nose and soft-tissue profile, males were larger than females in nasal length, height and angular measurements. 4. In analysis of soft-tissue profile, males were larger than females in the length and thickness. In the angular measurements and proportion of soft-tissue profile, there were no significant differences between males and females.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제26권5호
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• pp.519-526
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• 2000

Osteoporosis has recently been recognized as a major health problem in the elderly population. The disorder is manifested as a loss of bone mass accompanied by structural alteration of bone and increased incidence of fracture. Mandible also may be affected. So, I evaluated panoramic views of 66 postmenopausal women for finding the possibility of useful diagnostic mandibular parmeters of osteoporosis. To know the correlationship between skeleton and mandible, the average of the bone mineral density of lumbar from 2nd to 4th by the dual energy X-ray absorptiometry(DEXA, LUNAR DPZ. USA), and age and mandibular parameters, that is, the number of residual teeth, alveolar ridge resorption ratio, panoramic mandibular index (PMI), mandibular cortical width (MCW), angular cortical thickness (ACT), ramus cortical thickness (RCT), morphology of mandibular inferior cortical (MIC) were compared. And I divided the all tested women to the osteoporotic group and non-osteoporotic group by the use of T-score -2.0, which was derived from skeletal bone mineral density (BMD). To find the correlationship of the each group with mandibular parameters, t-test and discriminant analysis were done. The results of the t-test were that all parameters were highly related with 2 groups (p<0.05). Especially ACT, MIC, age have had even higher correlationship than others (p<0.001). The results of the discriminant analysis by the use of these ACT, MIC and age were that the discriminant function was Z = -2.973+(-1.447)$\times$(ACT)+1.131$\times$(MIC score)+(0.052)$\times$(age), the cutting score was 0.257 and the classification accuracy was 84.8%. Therefore I suggest that the consideration of the angular cortical thickness (ACT), the age of patient and the morphology of mandibular inferior cortical(MIC) may help find the osteoporosis.

• 대한치과교정학회지
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• 제23권3호
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• pp.391-403
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• 1993

For the purpose of investigating mesiodistal axial inclination of posterior teeth in normal occlusion group, open bite and deep bite group and investigating the correlationship between the axial inclination of posterior teeth and overbite of anterior teeth, a cephalometric study was performed on the subjects consisted of normal occlusion group(40), open bite group(71 : Angle's Class I, Class II, division 1 25, Class III 25) and deep bite group(64 : Angle's Class I 23, Class II, division 1 21, Class III 20). Mesiodistal axial inclination of posterior teeth to occlusal, mandibular and palatal plane were measured. The findings of this study were as follows : 1. Upper and lower posterior teeth were more mesially inclined to occlusal plane in open bite group than in deep bite group. 2. Lower posterior teeth were more mesially inclined in deep bite group than in open bite group in Angle's Class II, division 1 malocclusion but there were no significant differences in Angle's Class I and Class III malocclusion. 3. There was no significant correlationship between the axial inclination of posterior teeth to each plane and overbite of anterior teeth in open bite group. 4. There was a significant correlationship between the axial inclination of upeer and lower second premolar to occlusal plane and overbite of anterior teeth in Angle's Class I, Class II, division 1 and Class III malocclusion.

• 대한치과교정학회지
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• 제24권4호
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• pp.787-798
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• 1994

The purpose of this study was three-fold: i) to investigate the degree of asymmetry in Angle's Class III malocclusion patients and normal adults; ii) to determine the nature of difference existed between two groups; and iii) to investigate the correlationship between the degree of asymmetry and ANB and overbite in Angle's Class III malocclusion patients. The subjects consisted of 25 Angle's Class III malocclusion patients and 25 normal adults and the mean ages were 22.0 and 24.5 years, respectively. Their posteroanterior and lateral cephalograms were traced and analysed with three-dimensional approach. The results were as follows: 1. Asymmetry of Angle's Class III malocclusion group was significant in all regions except cranial base. Their horizontal asymmetry was seen in mandibular angle, maxillary and mandibular 1st molar, mandibular midline and menton. Vertical asymmetry was observed in maxillary 1st molar and mandibular shape and anteroposterior asymmetry in mandibular angle. 2. Nine variables indicating asymmetry were selected and each variable had similar discriminant score. 3. There was a little correlationship between An and asymmetric variable(MSR-B6) and its correlation coefficients was 0.3564. 4. There was no significant correlationship between overbite and asymmetric variables.

• 한국보육학회지
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• 제17권2호
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• pp.159-179
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• 2017

본 연구는 경기도에 소재한 대학의 보육학과 학생들을 대상으로 핵심역량과 진로스트레스 그리고 진로포부간의 영향을 연구하였다. 구체적인 연구 결과는 다음과 같다. 첫째, 핵심역량과 진로포부 그리고 진로스트레스의 상관관계는 핵심역량이 높을수록 진로포부는 높아지고 진로스트레스는 낮아졌다. 둘째, 핵심역량과 진로포부가 진로스트레스에 미치는 영향을 중다회귀분석으로 살펴본 결과 핵심역량의 하위요인인 자질과 태도 및 능력역할과 진로포부는 진로스트레스에 유의미한 영향을 미치는 것으로 나타났다. 셋째, 핵심역량이 진로스트레스에 미치는 영향에 대한 진로포부의 매개효과를 살펴본 결과는 핵심역량이 진로스트레스에 직접적인 효과는 유의하지 않았으나 진로포부를 매개로한 간접효과는 유의하게 나타났다. 핵심역량은 진로포부를 매개로 하여 진로스트레스에 영향을 미치고 있었다. 이 결과를 바탕으로 논의 부분에서는 연구에 대한 논의 및 제한 그리고 추후연구방향을 제시하였다.

• 대한치과교정학회지
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• 제26권3호
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• pp.267-279
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• 1996

교정치료는 치료 후의 분석이 이루어져야 그 성공여부를 평가받을 수 있다. 왜냐하면 교정치료는 환자자신의 고유한 균형을 변화시켜 또 다른 균형을 설정해가는 과정이기 때문이다. 그러나 1급이나 2급 부정교합에 비해 3급 부정교합 환자에 대한 연구는 미비하였다. 이 연구는 일반적인 교정치료시와 보정기간 중에는 어떠한 변화과정을 겪으며, 이들 중 재발 양상을 나타내는 요소에 대하여 치료 전의 골격형태와 치료기간 중 변화량과의 상관관계를 알아보고자 시행하였다. 초진시의 Heilman dental age가 IIIB이상이며 1년 6개월이상의 보정기간이 경과한 24명 을 대상으로 하여 치료기간과 보정기간 중에 각항목의 변화량을 비교하고 이중 복귀현상을 나타낸 항목에 대한 상관관계를 분석하여 다음과 같은 결론을 얻었다. 1. FH plane에 대한 교합평면의 각과 하악평면의 각, 그리고 하악평연에 대한 하악 전치의 각은 치료기간중의 변화가 보정기간 중에 치료전의 상태로의 복귀현상을 나타내었으며 이중 교합평면각과 하악 전치의 치축항목은 치료기간중의 변화량과 역상관 관계를 나타내었다. 2. 치료 종료시 교합평면의 상방변위가 보정기간 중에 원래의 형태로 복귀하려는 경향을 보였으며 이는 치료기간 중에 변위량과 비례하여 나타났으나 기저골에 대한 상하악 대구치의 경사는 치료기간중의 변화량이 보정기간에 일정하게 유지되었다. 3. 보정기간 중의 하악평면각은 치료기간 중의 하악의 후하방 회전량이 클수록 감소하였다.