• The korean journal of orthodontics
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• v.34 no.1 s.102
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• pp.1-11
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• 2004

Predicting the arch length discrepancy by simply comparing the available arch perimeter with tooth materials is merely a 2-dimensional analysis of the teeth movement. However, the real teeth movement takes place 3-dimensionally and is affected by various factors such as, the arch fen the curve of Spee and the axis of the incisors. The purpose of this study is to clarify the relationship between the decrease in the arch perimeter and the horizontal positional change of the incisors after extraction of the 1st bicuspids, for more analytic evaluation of the arch length discrepancy at pre-treatment model analysis stage. In addition to that to evaluate the effect of the curve of Spee, teeth axis to the basal plane, and the incisional crowding to the treatment outcome. All patients were treated at the department of orthodontics, dental hospital, Yonsei university. Inclusion criteria for patients selection were as follows. $\cdot$ Angle classification I malocclusion with bialveolar protrusion $\cdot$ Extraction of 4 1st bicuspids $\cdot$ No tooth anomaly or prosthesis $\cdot$ No abnormal attrition $\cdot$ No ectopically erupted teeth $\cdot$ Angle classification I canine and molar relationship $\cdot$ Less than 3mm of crowding Model analysis of the above patients was performed and the following conclusions were obtained. 1. When the intercanine distance was maintained, the available space for the distal movement of the mandibular incisors after the extraction of the 4 1st bicuspids was larger than the space provided by the extraction of the 4 1st bicuspids. However the difference was less than 1mm. The more tapered the anterior arch form, the larger the difference. 2. Compared to the situation in which the intercanine distance was maintained, when the intercanine distance was expanded to meet the width of the Posterior teeth, the incisors could move about 3mm more distally. 3. The positional difference of the incisal tip was insignificant whether the central incisors were moved by tipping or bodily movement. 4. When the anterior crowding was solved without changing the intercanine distance, the larger the anterior arch length was, the more the anterior movement of the incisors. 5. When the curve of Spee was levelled, the increase in the arch perimeter was less than half of the deepest curve of Spee.

• The korean journal of orthodontics
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• v.31 no.2 s.85
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• pp.283-300
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• 2001

With socioeconomic development and change of esthetic recognition, the demand for orthodontic treatment and number of orthodontic patients has been increasing so rapidly. And frequency of malocclusion was changed. So this study was done in an attempt to provide an epidemiologic study so that we can accomodate their orthodontic needs adequately and to obtain the reliable quantitative information regarding the characteristics of orthodontic patients. Distribution and trends were examined in 3,070 malocclusion patients who had been examined and diagnosed at Department of Orthodontics, Dental Hospital, Chosun University over 10 year-period from 1990 to 1999. The results were as follows : 1. The number of patients per year was increasing trend and higher visiting rate in female(56.5%) than in male(43.5%). 2. Age distribution had shown 7${\sim}$ 12 year-old group being the largest(37.9%) and each percentage of 13${\sim}$18, 19${\sim}$24, above-19, 0${\sim}$6 year${\sim}$old group was 32.0%, 19.6%, 7.1%, 3.4%. 3. Hellman dental age IVa which is completion of the permanent dentition showed the highest percentage in male and female. 4. Geographic distribution showed a majority of patients in Kwang Ju(71.0%). Group within the distance 10km from Chosun Dental Hospital was 56.3% and group within 20km was 14.7%. 5. Anterior cross bite showed the highest percentage in chief complaints and percentage of Mn. prognathism and protrusion of Mx. teeth was 12.6%, 12.2%. 6. Distribution in the types of malocclusion according to the Angle's classification had shown; 38.9% for Class I, 20.7% for Class II division 1, 2.0% for Class III division 2, 38.4% for Class III. 7. In the dental vertical dysplasia according to the Angle's classification, deep bite was the most frequent in Class II div.1 and div. 2(24.3%, 56.7%) and open bite in Class III(21.4%). 8. In the skeletal sagittal dysplasia, 39.3% of skeletal Class II was due to the undergrowth of the mandible and 46.3% of skeletal Class III was due to the overgrowth of the mandible. 9. Distribution in orthodontic treatment acceding to the extraction and nonextraction had shown 66.9% for nonextraction case, 33.1% for extraction case, and four first bicuspids have been extracted in the highest percentage(38.6%). 10. Patients who had orthognathic surgery comprised 7.9%, with an increasing trend.

• The korean journal of orthodontics
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• v.9 no.1
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• pp.39-65
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• 1979

The purpose of this study was to investigate the pattern of irregularities of teeth in various malocclusion groups. The subjects consist of 803 out-patients (355 males, and 448 females) in department of Orthodontics of S.N.U. Hospital, Yonsei University, and Kyunghi University Hospital. The results were as follows. 1. The proportions of subjects on the basis of Angle's Classification were 39.2% (42.2% male, and 57.8% fomale) in class I malocclusion, 29.0% (44.6% male, and 55.4% female) in class II. div. 1., 3.5%(46.4% male, and 53.6% female) in class II. div. 2., 28.3%(46.3% male, and 53.7% female) in class III. 2. Considering all the subjects, the percentage of teeth crowding was 67.8% (45.0% male, and 55.0% female). In class I malocclusion, the percentage of Crowding was 70.8%(43.5% male, and 56.5% female) with higher frequency in upper anterior teeth than in lower anterior. 3. The percentage of Maxillary anterior diastema was 25.6% (45.6% male, and 54.4% female) on the whole. In class II. div. 1. malocclusion, the percentage was 28.8% (46.3% male, and 53.7% female) and in class III, the percentage was 19.8% (46.7% male, and 53.3% female). Thus, frequency of maxillary anterior distema, was comparatively higher in class II. div. 1. than in class III. 4. The percentage of high canine was 25.1% (53.2% male, and 46.8% female) on the whole, and was 86.0% male and 76.6% female in right side, 73.0% male and 72.3% female in left side. In calss II. div. 2., the percentage was 53.6% (46.7% male, and 53.3% female ). In class II. div. 1., the percentage was 16.7% (46.2% male, and 53.8%) with higher frequency in class II. div.2. 5. The percentage of deep overbite was 23.0% (43. 2% male, and 56.8% female) on the whole. Ia class 11. div. 2., and in clas sll. div. 1., its were 89.3%(48.0% male and 52.0% female), 54.5% (40.9% male, and 59.1% female) respectively. This result can be considered as one of the characterics of Angle's class 11 malocclusion group. 6. The percentage of spacing was 23.0% (36.8% male, and 63.2% female) on the whole, In class II. div. 1., and in class II. div. 2., its were 26.1% (44.3% male, and 55. 7% female), 7.1% (50.0% male, and 50.0% female) respectively. 7. The percentage of open bite was 14.3% (42.6% male, and 57.4% female) on the whole with higher rate on the anterior part. It rated 17.6%(50. 0% male, and 50.0% female) in class III, but none in class II. div. 2. 8. The percentage of crossbite was 22.5% (55.8% male, and 44.2% female) on the whole, with higher frequency on the anterior part than on the posterior part. In Angle's class III, it rated as much as 55.1% (57.6% male, and 42.4% female). 9. The percentage of edge-to-edge bite was 20.4% (47.6% male, and 52.4% female) with higher frequency on anterior part than on posterior part. 10. The percentage of irregularities of teeth in various malocclusion groups, was 21.5% (24.8% maxillary, and 18.1% mandible) in crowding, 20.8% (23.5% maxillary, and 18.0% mandible) in rotation, 10.7% (10.6% maxillary, and 10.8% mandible) in cross bite, 9.5% (11.8% maxillary, and 7.3% mandible) in spacing, 8.5% (8.5% maxillary, and 8.5% mandible) in edge-to-edge bite, 8.1% (8.3% maxillary, 7.8% mandible) in open bite. Crowding teeth, spacing teeth, and rotating teeh were more prevalent in anterior part than in posterior part. Cross bite teeth and edge-to-edge bite teeth were more prevalent in class III malocclusion than in another.

• The korean journal of orthodontics
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• v.29 no.2 s.73
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• pp.267-276
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• 1999

Distributions trends were examined in 9159 malocclusion patients who had been examined and diagnosed at Department of Orthodontics, College of Dentistry Yonsei University over a 6 year-period from 1992 to 1997. The results were as follows ; 1. The total number of orthodontic patients in 1997 increased in comparing with that of 1992(86%) and after 1995, the number of annual patients showed an increase. 2. Age distribution had shown over-19 year-old group being the largest(39.9%) but percentages of pre-adolescent patients had been decreasing while that of adult patient had gradually increased. 3. Distributions in the types of malocclusion, the Angle's Classification had shown : 33.3% for Class I, 28.6% for Class II and the largest 38.1% for Class III. 4. Among Class I patients, crowding showed the largest(32.6%) and protrusion group had gradually increased to 33.9% in 1996. Otherwise openbite and crossbite groups tend to decrease, annually. 5. Geographic distribution showed a majority of patients from Seoul(above 70%). Among the patients from Seoul, group within the distance 3-6Km from Yonsei dental hospital was the largest(32.3%) and group within 9Km showed 69% of total patients.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.1
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• pp.113-121
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• 2000

This study was aimed to provide an epidemiologic study so that we could accommadate their orthodontic needs adequately and to obtain the reliable quantitative information regarding the characteristics of orthodontic patients who visited the Department of pediatric dentistry, Chonnam National University Hospital from 1986 to 1999, October. The results were as follows. 1 The total number of orthodontic patients were 1,381(male 658, female 723) and the number of annual patients showed irregular trend and the number of male were slightly higher than that of female. 2. According to the investigation made by age group, the group of under 5 years, 6 to 7, 8 to 9, 10 to 11, 12 to 13 and above 14 years showed 8.4%, 29.6%, 34.3%, 21.2%, 5.7% and 0.8%, respectively. 3. The patients corresponding to primary dentition were 15.7% of total patients and mesial step, distal step and flush terminal plane were 83%, 4.6% and 12.4% respectively. By the way 82% of mesial step had anterior crossbite at the same time. 4. The patients corresponding to Angle classification were 84.3% of total patients and Class I malocclusion, Class II div. 1, Class II div. 2 and Class III was 34.7%, 34.6%, 2.1% and 28.6%, respectively.

• The Journal of Engineering Geology
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• v.14 no.2
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• pp.199-210
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• 2004

In this study, the physical and mechanical properties of the weathered shale soils distributed in the Hwasun area have been measured in the laboratory. The physical and mechanical properties of the weathered shale soils in the study area as follows: the specific gravity is 2.66 to 2.68, the liquid limit is 36.39 to 36.92(%), the plastic limit is 18.53 to 19.48(%), the plasticity index is 17.44 to 17.86 and soil classification is CL. The maximum dry unit weight and optimum moisture content as calculated by compaction test is 22.5 to 23% and 1.58 to $1.61t/\textrm{m}^3$, respectively. The result of direct shear testing show that cohesion in saturated and unsaturated conditions increases according to the increase of dry unit weight. Internal friction angle in an unsaturated condition increases with an increase of dry unit weight, but in a saturated condition, it increases after decreasing. When compares with engineering characteristics of tile weathered shale soils in the Daegu area (Kim et al., 1995), specific gravity is found to be similar, but the liquid and plastic limit of soil samples in this study area is slightly higher than those of soil samples in the Daegu area.

• Journal of Embryo Transfer
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• v.22 no.2
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• pp.97-100
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• 2007

The objective of the present study was to investigate relationships between Caslick's index and fertility for different age groups of Cheju mares. Ninety-one Cheju mares were used for this study. Caslick's index was measured the effective length and angle of declination of the vulva in the mare. They were mated naturally by stallions from February to October during the years $2002{\sim}2005$. The classification used in the present study was : Group I - good conception every years, Group II - conception every other year and Group III - Barren. Younger aged group ($3{\sim}7$ years) had a lower Caslick's index (<50) compared with $8{\sim}14$ aged group and older aged group (> 15 years). In this study, Caslick's index was increasing by increasing age of Cheju horse like Thoroughbred. However, fertility was decreasing by increasing Caslick's index. Hence, there was significant association between the different Caslick's index and fertility. Further research is needed to determine relationship between different Caslick's index and endometritis.

• The Journal of Engineering Geology
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• v.25 no.2
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• pp.189-199
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• 2015

Our country's leading granite weathered soil of the ground slope failures that occur in cutting slope most cases, it does not require in-depth to the shear strength most of the surface layer is affected by weathering (1~2 m) at a shallow depth close to the ground, it is important to identify the reliability. Based on the result obtained in actual field investigation, the field slope type was classified by each type of wedge slope, Infinite slope, finite slope -I and finite slope -II, and the slope stability was examined respectively. In addition, using the numerical analysis results, the relationship between the slope inclination angle and safety factor was analyzed and it tried to offer basic data to which the stability in the field slope was able to be estimated by analyzing the safety factor change of the slope according to the slope type. In this study, classified into four types of natural slope, safety factor estimation method by slope types is proposed through the numerical analysis. However, some limit exists in generalizing in this research because it does not test various case studies. Therefore, the case study of a wide range of various sypes to assess the safety of various types slope can be made, accommodate a wide range of field conditions reasonable risk evaluation criteria may be derived.

• Korean Journal of Human Ecology
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• v.12 no.1
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• pp.75-84
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• 2003

The objective of this paper was to analyse the foot type of female university students by the direct and indirect measure of foot and the measures of foot outline. The results were as follow: 1. The length and the width of foot were small and ankle slender and the modification of the big toe slight. 2. The analysis on the 16 measure items revealed five factors; the first factor was related to the width and girth of foot, the second one to the length of foot, the third one to the transformation of the little toe, the fourth one to the height of foot, the fifth one to transformation of the big toe. 3. The grouping on the shape of foot revealed three types. The inline angle of foot was the smallest in average in the type 1, while it appeared to be middle in the other types. The wider foot shapes were grouped as type 2 because their inline and outline angles of foot were the biggest in average. In the type 3, the big toe was curved a lot, since it was the largest in average. 4. From the naked eye measuring method, classification from which toe was popped-out told that Egyptian foot was 30.9%, Greek foot 27.9%. On the other hand, the instrumental method showed that Egyptian foot was 57.3%, Squared foot 35.3% and Greek foot 7.4%. 5. The result from the analysis about the traits of foot shape by the degree of the arch formation of bottom foot, showed that 33.8% had the normal foot, 66.2% slightly flat foot or middle one. There was no one with rigid flat foot. 6. The shoes size they declared were that 240cm was 33.3%, 235cm 18.1% and 245cm 18.1%. The shape of their shoe heel were flat heel(34.8%), cuban heel(25.5%), and narrow straight heel(19.9%); and that of the shoe toe were round toe(25.4%), oval toe(20.4%) and squared toe(20.4%). 7. The discomforting parts when they wear shoes were the little toe(35.4%), the rear of foot(13.9%), and the width of foot(13.9%), which was related to their dislike of shoe with the pointed toe.

• Journal of Broadcast Engineering
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• v.15 no.6
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• pp.768-782
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• 2010

Because of the different shooting position between multi-view cameras and the imperfect camera calibration, Illumination mismatches of multi-view video can happen. This variation can bring about the performance decrease of multi-view video coding(MVC) algorithm. A histogram matching algorithm can be applied to recompensate these inconsistencies in a prefiltering step. Once all camera frames of a multi-view sequence are adjusted to a predefined reference through the histogram matching, the coding efficiency of MVC is improved. However the histogram distribution can be different not only between neighboring views but also between sequential views on account of movements of camera angle and some objects, especially human. Therefore the histogram matching algorithm which references all frames in chose view is not appropriate for compensating the illumination differences of these sequence. Thus we propose new algorithms both the image classification algorithm which is applied two criteria to improve the correlation between inter-view frames and the histogram matching which references and matches with a group of pictures(GOP) as a unit to advance the correlation between successive frames. Experimental results show that the compression ratio for the proposed algorithm is improved comparing with the conventional algorithms.