• 대한치과의사협회지
• /
• 제19권1호통권140호
• /
• pp.67-71
• /
• 1981

This study was undertaken to find out the characteristic craniofacial morphology of Class II Division 2 malocclusions in children by means of roentgenocephalometry. The subjects consisted of twelve boys and thirteen girls with Class Ii, Division 2, thirty seven boys and fifty three girls with Class II, Division 1, and forty six boys and eighty one girls with normal occlusion, ranged from 10 years old to 18 years old. The following results were obtained; 1. The anteroposterior relationship of the maxilla to the cranium in the Class II, Division 2 malocclusion similar to the normal occlusion, but the mandible was the posterior position in th the cranial anatomy. 2. There were no significant differences in the anteroposterior relationship of the maxilla and the mandible between Class II, Division 1 and Class II, Division 2 malocclusions. 3. In Class II, Division 1 the axes of maxillary incisors showed labial inclination, but lingual inclination in Class II, Division 2 malocclusions. 4. Overbite was prominent one in Class II, Division 2, on the other hand overjet was distinguished in Class II, Division 1.

• 아동학회지
• /
• 제22권4호
• /
• pp.201-212
• /
• 2001

The purpose of this study was to analyze toddlers' verbal and nonverbal interaction with their peers and caregivers according to the class size of child care centers in Seoul. The subjects of this study were 20, two-year-old(M=32.5 month) toddlers with peers and caregivers from child care centers in different class sizes, but with same caregiver-toddler ratio. Verbal and nonverbal interactions were videotaped during one hour indoor free play per child in the center. According to the class size, the results were as follows : 1) Toddlers in the small class played more cooperatively with peers, and uttered more regulative or directive words than those in the large class. 2) Toddlers in the large class were more aggressive than those in the small class. 3) Caregivers in small class expressed more empathetic behaviors to a toddler than those in large class.

• 대한전기학회논문지:전기물성ㆍ응용부문C
• /
• 제55권6호
• /
• pp.287-290
• /
• 2006

A class-E CMOS RF(Radio frequency) power amplifier with a 1.8 Volt power supply is designed using $0.25{\mu}m$ standard CMOS technology. To drive the class-E power amplifier, a Class-F RF power amplifier is used and the reliability characteristics are studied with a class-E load network. After one year of operating the power amplifier with an RF choke, the PAE(Power Added Efficiency) decreases from 60% to 47% and the output power decreases 29%. However, when a finite DC-feed inductor is used with the load, the PAE decreases from 60% to 53% and the output power decreases only 19%. The simulated results demonstrate that the class-E power amplifier with a finite DC-feed inductor exhibits superior reliability characteristics.

• 대한치과교정학회지
• /
• 제45권3호
• /
• pp.113-120
• /
• 2015

Objective: This study compared occlusal contact areas of ideally planned set-up and accomplished final models against the initial in class I and II molar relationships at finishing. Methods: Evaluations were performed for 41 post-orthodontic treatment cases, of which 22 were clinically diagnosed as class I and the remainder were diagnosed as full cusp class II. Class I cases had four first premolars extracted, while class II cases had maxillary first premolars extracted. Occlusal contact areas were measured using a three-dimensional scanner and RapidForm 2004. Independent t-tests were used to validate comparison values between class I and II finishings. Repeated measures analysis of variance was used to compare initial, set up, and final models. Results: Molars from cases in the class I finishing for the set-up model showed significantly greater contact areas than those from class II finishing (p < 0.05). The final model class I finishing showed significantly larger contact areas for the second molars (p < 0.05). The first molars of the class I finishing for the final model showed a tendency to have larger contact areas than those of class II finishing, although the difference was not statistically significant (p = 0.078). Conclusions: In set-up models, posterior occlusal contact was better in class I than in class II finishing. In final models, class I finishing tended to have larger occlusal contact areas than class II finishing.

• 한국정보과학회 언어공학연구회:학술대회논문집(한글 및 한국어 정보처리)
• /
• 한국정보과학회언어공학연구회 2012년도 제24회 한글 및 한국어 정보처리 학술대회
• /
• pp.8-11
• /
• 2012

One-class SVM은 데이터가 존재하는 영역을 추출하고, 이 영역을 서포트 벡터로 표현하며 표현된 영역 밖의 데이터들은 아웃라이어(outlier)로 간주된다. 본 논문에서는 데이터 포인트마다 숨겨진 변수(hidden variable) 혹은 토픽이 있다고 가정하고, 이를 반영하기 위해 PoMEN에 기반한 Latent One-class SVM을 제안한다. 실험결과 Latent One-class SVM이 대부분의 구간에서 One-class SVM 보다 성능이 높았으며, 특히 높은 정확율을 요구하는 경우에 더욱 효과적임을 알 수 있었다.

• 인터넷정보학회논문지
• /
• 제19권5호
• /
• pp.107-113
• /
• 2018

Object-oriented databases (OODBs) canbe used for many non-traditional database application areas such as computer-aided design, etc. Usually those application areas require advanced modeling power for expressing complicated relationships among data sets. OODBs have more distinguished features than the traditional relational database systems. One of the distinguished characteristics of OODBs is class hierarchy (also called inheritance hierarchy). A class hierarchy in an OODB means that a class can hand down the definitions of the class to the subclass of the class. In other words, a class is allowed to inherit the definitions of the class from the superclass. In this paper, we present performance evaluation metrics for class hierarchy in OODBs from a concurrency control perspective. The proposed performance metrics are developed to determine which concurrency control scheme in OODBs can be used for a given class hierarchy. In this study, in order to develop performance metrics, we use class hierarchy structure (both of single inheritance and multiple inheritance), and data access frequency for each class. The proposed performance metrics will be also used to compare performance evaluation for various concurrency control techniques.

• Human Ecology Research
• /
• 제56권3호
• /
• pp.301-315
• /
• 2018

This study explores the critical reflection process experienced by home economics preservice teachers during practicum. Data were collected in a critical analysis of class, practicum review, and journals written by sixteen preservice teachers. Text material were composed of 188 transcripts on A4 paper and 36 page of mini-notes. The collected data were analyzed by a thematic coding method in qualitative research and proceeded in the order of three steps of transference, coding, and subject discovery. The emerging themes were: 1) Observing class 2) Practicing class 3) Growth of class practice 4) Reflecting class. First, the observing class was an exploration process through the viewing of daily classes that involved the process of recognizing the classroom situation and various classroom contexts. Second, the practicing class was to strengthen the consideration of the class to form a relationship that could lead to learning in educational situations. Third, the growth of class practice was intended to recognize the orientation of the subject matter with pedagogical content knowledge. Four, the reflecting class was the process of experiencing practice with a continuous understanding of the class, class reflection, and changing the perspective from the current status. There is a part where critical reflection is difficult to be promoted deeply during 4 weeks; however, there was a possibility of a reflection practice that could promote achievement through the experience of a practicing class.

• 대한치과기공학회지
• /
• 제42권4호
• /
• pp.394-401
• /
• 2020

Purpose: The present study is an analysis of the extents of class satisfaction of college students who had applied the design thinking technique to capstone design class. Methods: The experimental method involved an analysis of 122 cases of data where advance and post replies were performed for the subject by students who had applied the design thinking technique and students who had not. The students involved had attended the capstone design class as a junior in the Department of Dental Technology at D University. Results: In the satisfaction with performance process of the capstone design class, five questions among nine had a high positive rating, while all eight questions on the satisfaction with performance methods had a high negative rating. Among ten questions on subjective learning outcomes, six showed a high positive rating. After the application of the design thinking class method, all mean values of the group with the application were higher than the group with no application in satisfaction with performance process, satisfaction with performance method, and subjective class outcomes. Hence, the design thinking class did have positive effects on the students' improvement of class. Conclusion: Based on the results of the study, it is implied that the considerations about diverse class composition methods and operation methods capable of improving the students' satisfaction are needed for efficient operation of the capstone design class.

• 대한치과교정학회지
• /
• 제52권6호
• /
• pp.432-438
• /
• 2022

Objective: To compare crown-root angulations of the permanent maxillary anterior teeth in skeletal Class I, Class II, and Class III Korean malocclusion patients using cone-bean computed tomography (CBCT) images. Methods: Sixty CBCT images were collected from orthodontic patients archive based on skeletal Class I (0˚< A point-nasion-B point angle [ANB] < 4˚), Class II (ANB ≥ 4˚), and Class III (ANB ≤ 0˚) to have 20 samples in each group. Mesiodistal crown-root angulation (MDCRA) and labiolingual crown-root angulation (LLCRA) were evaluated after orientation of images. Crown-root angulations were compared among Class I, Class II, and Class III groups and among the maxillary anterior teeth in each group. Results: LLCRAs of the maxillary central incisor and the lateral incisor were significantly lower in Class III group than those in Class I group. However, those of the canine showed no significant differences among groups. MDCRAs of the maxillary anterior teeth did not significantly differ among groups either. Conclusions: Our results suggest that skeletal Class III malocclusion might affect LLCRA of the maxillary incisors, especially the central incisor.

• 대한치과기공학회지
• /
• 제29권2호
• /
• pp.197-211
• /
• 2007

With the development of orthodontics and increasing concerns on physical appearance, the number of patients has been steadily increasing. It is quite important not only to make effective cure plans and accurate diagnoses but also to have a thorough grasp of patients' malocclusion types and their occurrence frequency, in addition to patients' personality in order to cure the patients appropriately. This study is based on 946 malocclusion patients who had visited Chong-A Dental Hospital from 1999 to 2004 and investigated their aspects of malocclusion and characteristics of their gender, age and residence. The results are as follows. 1. The number of patients per year had been decreased until 2001, after which year the number had fluctuated. The number was the largest in 1999, 169 and the smallest in 2001, 140. Female occupied 68.0% of the total, twice as many as male, 32.0%) 2. Based on the Angle's classification, 19 or over year - old group was the largest of the total, 59.3% and 6 or younger year - old group, the smallest, 0.5%. The 19 or over year old group was less than a half of the total (47.4%) in 2003 and there were no patients who belonged to the 6 or younger year - old group in 2003 and 2004. 3. Distributions on the types of malocclusion have shown that 39.9 % of the total are in the Class I, the largest, 31.0% in the Class I and 29.2 in the Class II, the smallest. 1) The number of the ClassI was 73, the largest, that of the Class III being 35, the smallest in 1999. On the whole, the number of the Class I accounted for the largest part of the total. 2) The number of male patients in the Class II was the smallest, generally being the largest in the Class I. In case of female, that of the Class III was the smallest. 3) Based on the age, the Class I was the highest in between 7 and 13 age group, the Class III the lowest. The Class I occupied the largest around 40%. 4) In the shape of physiognomy, the meso occupied the largest part among all the Class, of which the Class II was the highest, 64.2%. The bracy was the largest in the Class I, and the dolicho in the Class III. 5) In the profile, the convex shape was the largest in the Class I and II, and especially in the Class II, over 3/4 of the total, 75.4%. In contrast, the direct shape was the largest in the Class III and the sunken shape occupied 33.3%, which was nearly ten times more than the case of the Class I and III. 6) In the asymmetry of physiognomy, the number of patients of the Class IIIwas the largest, 34.1% and that of the Class II, the smallest, 19.5%. It was found that about one fourth of the malocclusion patients were under the asymmetry of physiognomy. 4. In the distribution of patients' residence, 81.4% were from the Seoul Metropolis and 48.2% from Gangnam-Gu where Chong-A Dental Hospital is located and Seocho-Gu and Songpa-Gu which are adjacent to Gangnam-Gu.