• Journal of the korean academy of Pediatric Dentistry
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• v.11 no.1
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• pp.121-130
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• 1984

Childrens between the ages of 13 and 15 years, living in Seoul, were examined in order to determine the prevalence and severity of malocclusion in the permanent dentition. This survey encompassed 981 children and an individual chart was prepared for each subject recording an original HMAR score and classification of occlusion according to Angle. Also, subjective evaluation of "treatment needs" was carried out in 581 children. The results were as follows: 1. Of the 981 children in this survey, 12,1 percent showed excellent occlusion. (0 point) 2. The 14 percent of the children who had a score of 24 and above all appeared to belong to the "treatment highly desirable" or "treatment mandatory" category. 3. The incorporation of SAR (Supplementary Assessment Record) into the HMAR can provide more sensitive method for evaluating severity of malocclusion. 4. According to Angle's classification 77.4 percent of all malocclusion belonged to Class I, 1.3 percent to Class II, Division 1, 0.9 percent to Class II, Division 2, and 11.3 percent to Class III. 5. The mean HMAR score for Class I was significantly lower than for either Class II, Division 1 or Class III. (P < 0.05) 6. A close relationship was found between the degree of "treatment needs" and the value obtained by the HMAR scoring. (chi-square test, p < 0.05) The differences between the mean HMAR scores of the various subjectively defined categories were statistically significant. (P < 0.001)

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.23-24
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• 2021

The use of recycled concrete aggregates (RCA) as a substitute for natural aggregates in new concrete produces both economic and environmental advantages. Most of the RCA applications for pavements have been primarily applied to support layers for roads and airfields. This paper summarizes a work completed at the University of Illinois in partnership with the O'Hare Modernization Program to examine the effect of coarse and fine RCA on the concrete's fresh and hardened properties for airfield rigid pavement applications. Ten different RCA concrete mixtures were prepared with the incorporation of different percentages of RCA fines as well as replacement of cement with high volume percentages of supplementary cementitious materials such as Class C fly ash and ground granulated blast furnace slag to improve the workability and long-term properties of RCA concrete. All the mixes on this stage included 100% recycled coarse aggregates and the Two-Stage Mixing Approach was used as a mixing procedure. Based on the results obtained in the research, mixes with high percentages of recycled fine and coarse aggregates could be used for construction of airfield concrete pavements in conjunction with supplementary cementitious materials

• Journal of Educational Research in Mathematics
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• v.8 no.1
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• pp.183-197
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• 1998

Many schools of the secondary level have been recently carrying out 'differentiated class'based on ability grouping between classed(DC). They are usually consisted of three levels; high level available to enriched course, middle level, and low level available to supplemental course. Phrhaps, almost all of the schools might nave executed DC before 2000 year. To do this, a lots of teachers have to develop differentiated teaching and learning materials for themselves. But, these mateirals are usually consisted of differentiated mathematics not on 'content'but on 'items'. So, for the successful 7th differentiated curriculum, the issues such as teaching and learning methods, materials, and evaluation system should be considered in depth focused on DC. .Decide issues related to DC(for example, mathematical contents, methods, activities, class speed,extra)based not on teachers or experts but on students. .Differentiate teaching and learning mateirals according to DC and develop the materials(including guidelines, supplementary books, multimedia, extra) based not on mathematical items but on mathematical contents. .Introduce new mathematical concepts or laws using not only not only definition and explanation but also concrete examples or problems. .Suggest differentiated diverse projects related to mathematical subjects suitable to enhance students` thinking ability to each class. .Have students to develop projects successfully by collecting, representing, analyzing, and interpreting data through communications in a cooperative learning environment.

• Educational Technology International
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• v.8 no.1
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• pp.101-126
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• 2007

The purpose of this study was to investigate current practices in blended instruction. In particular, the study explored (1) the types of instructional delivery methods, technologies, and instructional components, (2) the reasons why faculty apply blend instruction, and (3) the advantages and challenges in delivering blended instruction. This study focused on the practices in the Universities that have the extensive doctoral research programs classified by the Carnegie Foundations. The survey was performed with the sample of faculty from 30 universities and the survey data included 133 faculties out of the total 1,000 randomly selected faculty members. Of the 133 responses, 111 (77.7%) participants had certain degree of experience, while 17 faculty (or instructors) (13.3%) did not have any practice with blended instruction. The most common instructional delivery format in the participating universities was blended instruction that added supplementary online instructional components in the class. Online Course Management Systems (CMS) and multimedia presentation tools were common technology for course delivery, and "discussion" was the most general instructional activity for the class. The participating faculty often preferred the blended format since it provides students and faculty with convenience, flexibility, active engagement, efficiency in using resource materials, and a feeling of connection between/among students and instructor. Benefits to the class were availability of more authentic experience and diverse curricular materials, and the instructional format that meets the needs of remediation and enhancement of students. This study addressed not only advantages and challenges of blended instruction, but also suggestions based on the comments by the participating faculty.

• Journal of Korean society of Dental Hygiene
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• v.2 no.1
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• pp.63-83
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• 2002

The purpose of this study was to serve as a basis for more efficient dental hygienist human resources utilization and for determining some of the right directions for supplementary education for dental hygienists, by examining how they actually worked and what they thought of job-related things. The subjects in this study were 537 dental hygienists who participated in a seminar by the Korea Dental Hygienist Association. After a survey was conducted, the following findings were given: 1. 50.2% of the dental hygienists investigated completed legally required eight-class education. Those who worked in clinics took less supplementary education classes than the others in the other types of dental institutions. The main reason they didn't receive supplementary education was financial burden and uncooperative employers. 73.2% took supplementary education at the association or its branches. The association was most favored by those in clinical sector as a place that provides supplementary education, followed by its branch and university in the order named. And the dental hygienists in public health sector preferred university most, and the next best favored one was the association and its branch in the order named. Those in clinical sector hoped to acquire clinical information on patient management, implant or aesthetics, and the dental hygienists in public health sector wanted to learn about health administration, public oral health operations and oral health education, which were different from what those in clinical sector wanted. 2. Regarding the period of service, 492% had worked for three years or more. This fact suggested that their service term and average age continued to grow. And they thought they would decide the retirement time on their own. 3. The most common yearly income ranged from 12 million won to 16 million won(40.7%). For-those in clinics, yearly income was 14.36 million won, and that of the dental hygienists who had worked for less than 3 years was 12.90 million won. 4. The Korea Dental Hygienist Association was most required to protect the rights and interests of the members and offer new knowledge and technology. 5. The largest group of them were engaged in patient management, and this type of job also was the most favored one for them to do. The greatest number of the dental hygienists in public health sector were in charge of dental treatment. 6. Concerning their turnover rate, 492% had never changed their occupation. Specifically, 70.0% of the respondents who had worked for less than 3 years had have no experience to do that. The time constraints for self-development and conflicts with other workers were the cause of their turnover. Those in dental hospital and general hospital changed their occupation chiefly due to the lack of time for self-development, and for the dental hygienists in clinics, the conflicts with other workers were the main reason. The above-mentioned findings suggested that the way the dental hygienists looked at things was undergoing change. The service area made a difference to their preference for the type of supplementary education and institution in charge of it, as those in public health and clinical sectors had a different opinion. And the dental hygienists in clinical sector had a different opinion as well, according to service area, about salaries, reason of not taking supplementary education, preferred type of supplementary education, cause of turnover, and type of occupation to which they hoped to change employment. To utilize and supply human resources in a more stabilized manner, job description should be more segmented, standardized and classified clearly, and dental hygienists should be motivated to perform their substantial jobs, including oral disease prevention, oral prophylaxis and oral health education. To make it happen, it seems that dentists are required to have a clear understanding of dental hygienist job and to change the way they look at it.

• Journal of Korean Home Economics Education Association
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• v.30 no.2
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• pp.137-147
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• 2018

The purpose of this study was to develop and examine the effects of flipped learning in ancient Mesopotamian costume history. The flipped learning class was designed to three steps(pre-class, in-class, after-class). Pre-class: Students learned the socio-cultural background of Mesopotamia by watching videos online and Mesopotamian costume with PPT. In-class: Students were evaluated for their prior learning through the quiz. After the quiz, the instructor had a supplementary mini-lecture. Then the advanced learning was progressed with the team project(Mesopotamian costume analysis) by online Louvre Museum. Students made a team presentation and the instructor provided feedback. After-class: The effectiveness of flipped learning was measured based on the students' self-reflective journals and class awareness surveys. As the results, students actively participated in flipped learning and the class was rated appropriate. Students were satisfied with the overall quality of the flipped learning class. The Effect of Flip Learning Classes in reflective journals were shown as 'related flipped learning style,' 'related online Louvre museum project,' 'understanding of cooperative learning,' and 'contents of the class'. In conclusion, the flipped learning applied to Mesopotamian costume history was positive as a learner-centered education.

• Journal of the Korean School Mathematics Society
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• v.2 no.1
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• pp.167-179
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• 1999

The aim of this study is to improve the basic learning ability of those who make poor progress in mathematics and to keep positive and active learning attitudes in class afterward by using problems whith both make them advance their basic learning ability and supplement lack of previous learning in class or after school. supplementary problems were developed by focusing the ability of basic calculation, the comprehension of concepts, principles, and rules by analyzing necessary contents precisely each domain after itemizing learning contents each unit. the results of the study are this: 1) The students who solved the problems, that were developed to improve the basic learning ability and to supplement the earlier learning during their classes or giving homework, made significant progress in their scholastic achievement; more than those who were not involved. 2) Meaningful changes were demonstrated in the motivation for achievement among the domains of learning attitudes before and after the experiment but, not in their interest, the consciousness of purpose, attention, voluntary and efficient learning as shown in their learning habits. In this study, therefore, the problems which were developed to improve the basic learning ability and to supplement the earlier learning by focusing on the competence for basic calculation, and the comprehension of concepts, principles and rules were effective positively only in the area of motivation for achievement. there were no meaningful differences in the other domains.

• Nuclear Engineering and Technology
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• v.53 no.3
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• pp.1004-1012
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• 2021

High density polyethylene (HDPE) pipe has many advantages over metallic pipe, and has been used in non-safety related application for years in some nuclear power plants (NPPs). Recently, HDPE pipe was introduced into safety related applications. The main difference between safety-related and non-safety-related pipes in NPPs is the design method of extra loadings such as gravity, temperature, and earthquake. In this paper, the mechanical behavior of HDPE pipe under various loads in pipe gallery was studied by finite element analysis (FEA). Stress concentrations were found at the fusion regions on inner surface of mitered elbows of HDPE pipe system. The effects of various factors were analyzed, and the influence of various loads on the damage of HDPE pipe system were evaluated. The results of this paper provide a reference for the design of nuclear safety-related Class 3 HDPE pipe. In addition, as the HDPE pipes analyzed in this paper were suspended in pipe gallery, it can also serve as a supplementary reference for current ASME standard on Class 3 HDPE pipe, which only covers the application for buried pipe application.

• Publications of The Korean Astronomical Society
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• v.32 no.1
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• pp.251-255
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• 2017

Submillimetre and millimetre-wave surveys with Herschel and the South Pole Telescope have revolutionised the discovery of strong gravitational lenses. Their follow-ups have been greatly facilitated by the multi-wavelength supplementary data in the survey fields. The forthcoming Euclid optical/near-infrared space telescope will also detect strong gravitational lenses in large numbers, and orbital constraints are likely to require placing its deep survey at the North Ecliptic Pole (the natural deep field for a wide class of ground-based and space-based observatories including AKARI, JWST and SPICA). In this paper I review the current status of the multi-wavelength survey coverage in the NEP, and discuss the prospects for the detection of strong gravitational lenses in forthcoming or proposed facilities such as Euclid, FIRSPEX and SPICA.

• Journal of The Korean Association For Science Education
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• v.10 no.1
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• pp.33-45
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• 1990

To achieve the aim of science education, it is known that warious teaching, and learning materials should have to be used. As a sub-textbook for primary science education, 'Sil Hum-Kwan Chal (Experiment and Observation), teaching and learing material are developed and using now in science. This material have following characteristics; (a) Soruce-book contains reading materials for additional information, various pictures to enririch the science concepts, and supplementary and enrichment activities. (b) Work-book consists of the detailed procedures of activities of experiments presented in the textbook, student can record the experimental procedures and results. (c) Operational manuals provide operation techniques for experimental equipments which are used in science class. In this study the using status are surveyed for the 3rd grade of primary school, and based on this survey the improvement plan are discussed in view of design, quantity and utility, of sub-textbook.