• Kyungpook Mathematical Journal
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• 제45권1호
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• pp.123-130
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• 2005

In this paper we discuss a class of analytic functions related to the starlike functions in the unit disk. We prove that this class belongs to the class of close-to-convex functions, we obtain the sharp coefficient upper bounds and distortion theorem of this class, we also get the convexity radius of this class.

• 대한치과교정학회지
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• 제48권6호
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• pp.349-356
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• 2018

Objective: This study was performed to investigate the alveolar bone of lower incisors in skeletal Class III adults of different vertical facial patterns and to compare it with that of Class I adults using cone-beam computed tomography (CBCT) images. Methods: CBCT images of 90 skeletal Class III and 29 Class I patients were evaluated. Class III subjects were divided by mandibular plane angle: high (SN-MP > $38.0^{\circ}$), normal ($30.0^{\circ}$ < SN-MP < $37.0^{\circ}$), and low (SN-MP < $28.0^{\circ}$) groups. Buccolingual alveolar bone thickness was measured using CBCT images of mandibular incisors at alveolar crest and 3, 6, and 9 mm apical levels. Linear mixed model, Bonferroni post-hoc test, and Pearson correlation analysis were used for statistical significance. Results: Buccolingual alveolar bone in Class III high, normal and low angle subjects was not significantly different at alveolar crest and 3 mm apical level while lingual bone was thicker at 6 and 9 mm apical levels than on buccal side. Class III high angle group had thinner alveolar bone at all levels except at buccal alveolar crest and 9 mm apical level on lingual side compared to the Class I group. Class III high angle group showed thinner alveolar bone than the Class III normal or low angle groups in most regions. Mandibular plane angle showed negative correlations with mandibular anterior alveolar bone thickness. Conclusions: Skeletal Class III subjects with high mandibular plane angles showed thinner mandibular alveolar bone in most areas compared to normal or low angle subjects. Mandibular plane angle was negatively correlated with buccolingual alveolar bone thickness.

• 대한치과교정학회지
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• 제24권4호
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• pp.827-839
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• 1994

This study was conducted to assess the positional changes of hyoid bone following the use of activator in Angles class III malocclusion patients with functional factors. For this study, 40 Angle's class I patients and 40 Angle's class III patients, totally 80 subjects were used. They are all in Hellman's dental age IIIB-IIIC ranges. In lateral cephalogram to compare Angle's class I group and Angle's class III group, and the positional changes of the hyoid bone before and after the use of activator in Angle's class III malocclusion group. The results were obtained as follows; 1. Comparison of Angle's class I group and Angle's class III group. In comparison to Angle's class I group, hyoid bone is more anteriorly and superiorly positioned in Angle's class III group. The hyoid bone showed reverse inclination to the mandibular plane in Angle's class III malocclusion group. 2. Comparison of the hyoid positional change before and after use of Activator in Angle's class III malocclusion group. The hyoid bone is displaced posteriorly and inferiorly in vertical relationship. The hyoid bone also showed counter-clockwise rotation. 3. No statistical difference was found between after Activator use data of Angle's class m malocclusion group and Angle's class I group. It is concluded that the hyoid bone in Angle's class III malocclusion group changed its position, similar to Angle's class I malocclusion group.

• 대한치과기공학회지
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• 제46권3호
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• pp.126-132
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• 2024

Purpose: This study aims to examine the impact of instructor-learner interaction on online class satisfaction, perceived academic achievement, and online class preference. Methods: From December 20, 2023, to February 10, 2024, this study surveyed students in the medical and public health departments of K University and D University located in Gangwon-do and Daejeon, respectively. Results: In the online class environment, instructor-learner interaction showed a significant positive correlation with online class satisfaction, academic achievement, and online class preference. On re-examination using regression analysis, it was found that among the subfactors of instructor-learner interaction, instructional support and instructor presence had a significant impact. Conclusion: The findings suggest that in an online learning environment, instructors must make efforts to help learners identify what they need to learn by repeatedly asking whether they understand the learning content and providing appropriate feedback.

• 한국운동역학회지
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• 제24권3호
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• pp.209-216
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• 2014

The purpose of this study was to explore the effect of 8 weeks after school classes of track sports on students' start motion through kinematic variables. 30 students in D National university of education participated for this study. These students divided into two groups, 17 students for experimental group and 13 students for control group. The two groups participated in general athletic class as common class, and the experimental group participated in after school class additionally. The general class taught track and jump skill for 3 hours a week, and the after school class taught only athletic running skill for 30 minutes a week. Pre and post test assessed to assess students' kinematic changes. Findings indicated that velocity and step rate were increased, and contact time, step length, displacement of center of mass were decreased in the experimental group. In the control group, early velocity, knee/hip angle velocity were increased, and contact time, step length, displacement of center of mass were decreased. In conclusion, the students who only participated in general class, could not maintain athletic skills obtained from the class. However, students who participated in both general and after school class accomplish athletic start skill. This is because Continuous learning effect helped students keep the skill and did not lose the skill. Thus, in order for students to learn specific sport skills, joining after school class with general class together is recommended.

• 대한수학회보
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• 제46권3호
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• pp.535-543
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• 2009

In this paper we study some properties of the Helton class of an operator. In particular, we show that the Helton class preserves the quasinilpotent property and Dunford's boundedness condition (B). As corollaries, we get that the Helton class of some quadratically hyponormal operators or decomposable subnormal operators satisfies Dunford's boundedness condition (B).

• 산업경영시스템학회지
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• 제41권2호
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• pp.56-64
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• 2018

In recent years, imbalanced data is one of the most important and frequent issue for quality control in industrial field. As an example, defect rate has been drastically reduced thanks to highly developed technology and quality management, so that only few defective data can be obtained from production process. Therefore, quality classification should be performed under the condition that one class (defective dataset) is even smaller than the other class (good dataset). However, traditional multi-class classification methods are not appropriate to deal with such an imbalanced dataset, since they classify data from the difference between one class and the others that can hardly be found in imbalanced datasets. Thus, one-class classification that thoroughly learns patterns of target class is more suitable for imbalanced dataset since it only focuses on data in a target class. So far, several one-class classification methods such as one-class support vector machine, neural network and decision tree there have been suggested. One-class support vector machine and neural network can guarantee good classification rate, and decision tree can provide a set of rules that can be clearly interpreted. However, the classifiers obtained from the former two methods consist of complex mathematical functions and cannot be easily understood by users. In case of decision tree, the criterion for rule generation is ambiguous. Therefore, as an alternative, a new one-class classifier using hyper-rectangles was proposed, which performs precise classification compared to other methods and generates rules clearly understood by users as well. In this paper, we suggest an approach for improving the limitations of those previous one-class classification algorithms. Specifically, the suggested approach produces more improved one-class classifier using hyper-rectangles generated by using Gaussian function. The performance of the suggested algorithm is verified by a numerical experiment, which uses several datasets in UCI machine learning repository.

• 대한치과교정학회지
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• 제14권2호
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• pp.233-239
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• 1984

The author studied on the tongue position, tongue space and intermaxillary space at 4 groups; normal occlusion 30 cases, Angle's Class I bimaxillary protrusion 29 cases, Angle's Class II malocclusion 26 cases, Angle's Class III malocclusion 26 cases. This study used the data from cephalometric films of female subject aged from 16 to 23 years. Following results were obtained; 1. Dorsal height in Angle's Class III malocclusion was greater than normal occlusion. 2. Anterior Intermaxillary Height in Angle's Class I bimaxillary protrusion and Angle's Class III malocclusion was greater than normal occlusion. 3. Tongue space in Angle's Class I bimaxillary protrusion was greater than normal occlusion. 4. The ratio of the tongue space to the intermaxillary space (T.S./I.S.) in Angle's Class II malocclusion was greater and the ratio in Angle's Class III malocclusion is lesser than normal occlusion.

• 수산해양교육연구
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• 제26권3호
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• pp.525-534
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• 2014

This study has examined the effect of after-school physical activity on body composition and health related fitness of middle school students. The duration of after-school physical activity training program of this study is 12 weeks, the training time in 1 hours warming-up 10 minutes, the skill training 45 minutes and cool down did in 5 minutes. Exercise frequency is 5 time per week. Height basketball class, soccer class, subject class showed statistically meaningful increase between group variance showed statistically meaningful. Weight basketball class, soccer class, showed statistically meaningful decrease. Muscle mass basketball class showed statistically meaningful increase, soccer class showed statistically meaningful decrease. Cardiopulmonary basketball class, soccer class, showed statistically meaningful decrease. Explosive muscular strength basketball class, soccer class, showed statistically meaningful decrease. subject class showed statistically meaningful increase, between group variance showed statistically meaningful. Flexibility basketball class showed statistically meaningful increase, soccer class. Muscular strength basketball class, soccer class, subject class showed not statistically meaningful different.

• 대한치과교정학회지
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• 제16권1호
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• pp.107-118
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• 1986

This study was designed to investigate the variation of mandibular pattern and cranial base and their association in the craniofacial malocclusion. The material was the 165 cephalometric radiographs taken from craniofacial malocclusion. The sample was devided into two groups by age child group aged from 10 to 13 years and adult group aged over 18 years, and each group was devided into 3 types of malocclusion; class I, Class II div. 1 and Class III malocclusion. Child group consist of 35 samples and adult group consist of 20 samples in each malocclusion type. Various angular and linear measurements on the cephalometric radiographs were recorded and statistically analyzed. The results of the study were as follows; 1. The cranial base angle was largest in Class II div. 1 malocclusion and smallest in Class III malocclusion 2. The anterior cranial base length was largest in Class II div. 1 malocclusion but posterior cranial base length did not show statistical difference. 3. The mandibular body length of Class III malocclusion was larger than those of Class I and Class II div. 1 malocclusion in the adult group but did not shown difference in the child group. The ramus height of Class III malocclusion was larger than those of Class I and Class II div. 1 malocclusion in the child and adult group, but there were no difference between Class I and Class II div. 1 malocclusion. 4. The mandibular position was showed low correlation with the cranial base angele.