• The korean journal of orthodontics
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• v.45 no.3
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• pp.113-120
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• 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.

• Journal of Educational Research in Mathematics
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• v.8 no.2
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• pp.587-603
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• 1998

Being in Learning-accomplishing rate on mutual cooperation studies of small group by different class, we can find that the sujective class of high group is much more efficient than the compared class of high group and that the subjective class of low group is more efficient than the compared class of low group as times goes. Moreover, in analysis of all directions on mathematical attitude, high group appears to be a great efficient in all areas such as confidence, flexibility, reaction, value, etc. and low group seems to have a little effect, by comparing the subjective class with the compared class. A. The result of a scholastic ability test High group had a great effect in the result of the first (Number and an expression) and second(An equation of a figure) scholastic ability test. As the time of research goes, the difference of average between the subjective class and the compared class has increased. Low group had no effect in the result of the first (Number and an expression) and the second (An equation of figure) scholastic ability test. But the difference of average grade between the subjective class and the compared class proved to be some efficient as time goes. (the first test is 0.94 and the second test is 3.33)We can find that the result of the third test (An exponent and log function) turned out be efficient. B. The change of mathematical attitudeHigh group had a great effect in confidence(+1.21), fiexibility(+1.92), will(-0.06), curiosity(+2.64), reaction(+1.50), value(+1.44). Low group appeared to be a little efficient in comparison between the subjective class and compared class. the average of both the subjective class and the compared class in low group decreased if not the result of pre-test but in that of pose-test. Therefore, we can find that the difference between mathematics of maddle school and that of high school gets bigger in Low group.C. The result of a question examinationAfter this research, the reaction that It is helpful to studying accomplishm- ent is 33.7%, the reaction that It is not helpful is 14.7%. After all, this research appears to be a positive reaction. After this study, the change of studying will seems to be much more not in Low group but in High group.

• Korean Journal of Applied Biomechanics
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• v.24 no.3
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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.

• Journal of information and communication convergence engineering
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• v.6 no.2
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• pp.154-157
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• 2008

A class-E RF(Radio Frequency) power amplifier for wireless application is designed using 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. The reliability characteristic is improved when a finite-DC feed inductor is used instead of an RF choke with the load. After one year of operating, when the load is an RF choke the output current and voltage of the power amplifier decrease about 17% compared to initial values. But when the load is a finite DC-feed inductor the output current and voltage decrease 9.7%. The S-parameter such as input reflection coefficient(S11) and the forward transmission scattering parameter(S21) is simulated with the stress time. In a finite DC-feed inductor the characteristics of S-parameter are changed slightly compared to an RF-choke inductor. From the simulation results, the class-E power amplifier with a finite DC-feed inductor shows superior reliability characteristics compared to power amplifier using an RF choke.

• Bulletin of the Korean Mathematical Society
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• v.56 no.2
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• pp.365-371
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• 2019

If 𝖃 is a class of groups, denote by F𝖃 the class of groups G such that for every $x{\in}G$, there exists a normal subgroup of finite index H(x) such that ${\langle}x,h{\rangle}{\in}$ 𝖃 for every $h{\in}H(x)$. In this paper, we consider the class F𝖃, when 𝖃 is the class of nilpotent-by-finite, finite-by-nilpotent and periodic-by-nilpotent groups. We will prove that for the above classes 𝖃 we have that a finitely generated hyper-(Abelian-by-finite) group in F𝖃 belongs to 𝖃. As a consequence of these results, we prove that when the nilpotency class of the subgroups (or quotients) of the subgroups ${\langle}x,h{\rangle}$ are bounded by a given positive integer k, then the nilpotency class of the corresponding subgroup (or quotient) of G is bounded by a positive integer c depending only on k.

• Honam Mathematical Journal
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• v.34 no.3
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• pp.391-401
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• 2012

B. C. Berndt has found a transformation formula for a large class of functions, which comes from a transformation formula for a more general class of Eisenstein series. In this paper, using his formula which is 'twisted' by change of variables, we find a class of infinite series identities.

• Korean Journal of Community Nutrition
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• v.9 no.3
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• pp.326-332
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• 2004

The research objective was to identify the effect of various instruction media on improving students' foodservice management competencies and for increasing class satisfaction. The research involved a comparison of two student groups. One group consisted of students who attended a lecture-based food purchasing class (Group A). The other group was students who attended the same class, and who also used various media as well as receiving the lecture (Group B). The results were as follows: 1) After a 16 week program, Group B perceived their procurement management competencies to be higher than those of Group A, especially in setting up purchasing goals, marketing research, and using computer systems for procurement; 2) In terms of class satisfaction, it was also observed that Group B was more satisfied with food purchasing class than was Group A. Group B gave high scores, especially in effective utilization of media, increasing motivation, and understanding; 3) Group B perceived that various instruction media was helpful for developing their procurement management competencies. Respondents evaluated the usefulness of media in the following order: using Power Point watching videos, visiting web-sites for food purchasing class, and surfing the World Wide Web. The results of the research show that using various instruction media for food purchasing classes would improve students' foodservice management competencies. Therefore, instructors who teach foodservice management related courses should consider developing teaching strategies that apply various instruction media for students to enhance their foodservice management competencies and to increase class satisfaction.

• Journal of the Korean Society of Clothing and Textiles
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• v.47 no.4
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• pp.666-683
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• 2023

This research aims to develop based clothing design process tailored to the industry-university collaborative setting and apply it in a fashion design class. into three distinct phases: designing and organizing our fashion design class, conducting our class at a university, and gathering student feedback. First, we conducted a literature review on employing new technologies in traditional clothing design processes. We consulted with industry professionals from the Samsung C&T Fashion Group to develop an AI-based clothing design process. We then developed in-class learning activities that leveraged fashion brand product databases, a supervised learning AI model, and operating an AI-based Creativity Support Tool (CST). Next, we setup an industry-university fashion design class at a university in South Korea. Finally, we obtained feedback from undergraduate students who participated in the class. The survey results showed a satisfaction level of 4.7 out of 5. The evaluations confirmed that the instructional methods, communication, faculty, and student interactions within the class were both adequate and appropriate. These research findings highlighted that our AI-based clothing design process applied within the fashion design class led to valuable data-driven convergent thinking and technical experience beyond that of traditional clothing design processes.

• Educational Technology International
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• v.19 no.2
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• pp.175-197
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• 2018

Flipped classroom (FC) has gained attention as an active learning approach. Designing effective out-of-class activities to help prepare students for in-class activities is fundamental for successful implementation of FC. This study investigated the effectiveness of Goal-Based Scenarios (GBS) for out-of-class learning in FC. Four out of twelve units in a medical humanities course for Year 2 medical students was redesigned into a FC format, where e-learning modules were designed using a GBS approach for out-of-class activities and classroom debates were implemented for in-class activities. The other eight units were delivered in a conventional classroom debate format, which included reading text materials as pre-class assignments. A formative evaluation study was conducted using questionnaires and interview methods and students' academic achievements were evaluated by comparing their pre- and post-test scores between FC and conventional units. Students had positive perceptions of the e-learning modules in GBS approach and preferred the structure of learning in the FC format. Students' pre-test scores were slightly higher in the FC units, yet their post-test scores were comparable with conventional units. This study illustrates students' perceptions that the learning was bettered structured in FC and that the out-of-class learning using the GBS approach helped them better prepared for in-class activities.

• Journal of Gifted/Talented Education
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• v.20 no.1
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• pp.317-346
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• 2010

The purpose of this study was to investigate the changes in teachers' recognition of science class and children for the gifted, and the process of changes in their practical knowledge after the experience of science class and conversation with colleague teachers. Two elementary teachers, teacher A and B, were selected as subject of investigation, who wanted to improve their science class. They experienced the process of self-examination during their class and from class conversations. Teacher A has 10 years of teaching experience. She has been in contact with gifted children and observed them since undergraduate. She entered the graduate school since she came to be interested in science class and children for the gifted. While teacher B has only three years of teaching experience and had a first contact with the gifted after graduate school. The results of this study are as follows. Teacher A didn't change recognition of gifted children class by class conversation in short term because she had a firm faith in good class teaching and was rich in class teaching knowledge. And, her practical knowledge was applied to the next class by changing teaching method or by supplementing her class contents in concerned part through class observation and class conversation with her colleagues. Teacher B was characterized as being lack of class confidence and concerned more about subject knowledge. She was forming a new practical knowledge along with new class teaching knowledge. Teacher B was in trouble with applying new practical knowledge to next class. From such findings, it was concluded that the process of changing or forming of practical knowledge depends on the beliefs, values, experiences, or knowledges of each teacher. A reflection on one' own class teaching could be a good way to form a practical knowledge and improve teaching speciality, when it was concerned with self-reflection of their own class, class observation, and communication with colleagues. Thus, the reflection practice could be applied to the teaching program of teachers for the gifted to form practical knowledge through trial class, self-reflection of class, and conversation with colleagues.