• Journal of the Korean School Mathematics Society
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• v.14 no.4
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• pp.477-490
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• 2011

The concept of pedagogical content knowledge (PCK) has been developed and expanded to identify essential components of mathematical knowledge for teaching (MKT) by Ball and her colleagues (2008). This study proposes an alternative perspective to view MKT focusing on key developmental understandings (KDUs) that carry through an instructional sequence, that are foundational for learning other ideas. In this study we provide constructive components of KDUs in fraction multiplication by focusing on the constructs of 'three-level-of-units structure' and 'recursive partitioning operation'. Expecially, our participating preservice elementary teacher, Jane, demonstrated that recursive partitioning operations with her length model played a significant role as a KDU in fraction multiplication.

• Journal of Korean Academy of Nursing
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• v.45 no.6
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• pp.910-918
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• 2015

Purpose: Safety of humans is an important factor that affects health overall, and injuries are one of the major public-health problems in the world. The purposes of this study were to describe the International safe Community movement which contributes to the injury prevention and safety promotion all over the world, and to identify out the application and developmental strategies for Korea. Methods: A review was done of previous research, reviews, and reports on the history, concepts, basic principles, and recommendations for actions of the Safe Community. Results: For this study, the application strategies of the International Safe Community movement in Korea were examined to deduce the strengths of the safe Community program. Community-based injury prevention work according to the International Safe Community model is a successful and cost-effective way of reducing injuries in the community. Conclusion: Through the International Safe Community program, communities are able to realize a healthy community and achieve improved quality of lives for the people, which is the ultimate objective of the Safe Community model. In addition, it will contribute to the economic vitalization and gain through energy and enhancement of productivity of people.

• Journal of the Korean Home Economics Association
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• v.36 no.11
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• pp.119-128
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• 1998

This study was designed to find tendencies of housing value orientation of the model steel house visitors. Questionnaires were collected in June, 1997, 1,550 in total, 508 cases from Seoul, 456 cases from Pohang, and 486 cases from Kwangyang. Data were analyzed in terms of housing value orientation, using statistical methods including frequencies, mean, percentages, chi-square test and multiple regression. The major findings are as follows; 1. The subjects were highly educated(64% of them were college graduates) with the monthly income over 2,000,000won(approximately $1,540). The average monthy income of the subjects in Seoul, about 4,000,000won($3,070), was much higher than that of other areas. Most of the subjects were condominium owners(72%), who preferred single detatched houses or town houses located in suburban areas. 2. Differences in general tendencies among the three regional groups were statistically significant. Most significantly, subjects living in Pohang regarded the reputation of the building construction company most importnat. Subjects of all three regional areas, especially in Pohang, emphasized investment value. The price of the steel house was regarded as very important by all the groups tested. The housing value orientation was analyzed in 3 aspects; (1) Facility.Plumbing.Structure(FPS), (2) Interior space formation.Design(ID) and (3) Developmental complex.Near Environment(DN). Interior environment level, stability of house structure, and finighing state of interiors were identified as the important factors in the area of FPS(p<.05). The Interior plan organization was the most important factor among ID. As for DN, rated importantly were educational facilities, green areas, convenience of commercial facilities within the developmental complex were rated importantly.

• Development and Reproduction
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• v.12 no.1
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• pp.9-18
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• 2008

All the organisms on the earth are affected by the repeating signals from the ambient environment caused by the movements of the sun and the earth. Their physiological and behavioral activities such as reproduction, functional pathway of various molecules, and developmental stage, are reflected by the cyclicity whether it is daily(circadian) or annual rhythms. An essential function of circadian rhythms is to provide an internal estimate of the external local time, thereby allowing the organism to program its activities so that they occur at an appropriate time in the daily environment. Of many rhythmic patterns, the circadian rhythms are considered in this review, focusing on the limit cycle, which is a model to investigate the entrainment.

• Clinical and Experimental Reproductive Medicine
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• v.39 no.3
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• pp.95-106
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• 2012

It has been revealed that multiple cohorts of tertiary follicles develop during some animal estrous cycle and the human menstrual cycle. To reach developmental competence, oocytes need the support of somatic cells. During embryogenesis, the primordial germ cells appear, travel to the gonadal rudiments, and form follicles. The female germ cells develop within the somatic cells of the ovary, granulosa cells, and theca cells. How the oocyte and follicle cells support each other has been seriously studied. The latest technologies in genes and proteins and genetic engineering have allowed us to collect a great deal of information about folliculogenesis. For example, a few web pages (http://www.ncbi.nlm. nih.gov; http://mrg.genetics.washington.edu) provide access to databases of genomes, sequences of transcriptomes, and various tools for analyzing and discovering genes important in ovarian development. Formation of the antrum (tertiary follicle) is the final phase of folliculogenesis and the transition from intraovarian to extraovian regulation. This final step coordinates with the hypothalamic-pituitary-ovarian axis. On the other hand, currently, follicle physiology is under intense investigation, as little is known about how to overcome women's ovarian problems or how to develop competent oocytes from in vitro follicle culture or transplantation. In this review, some of the known roles of hormones and some of the genes involved in tertiary follicle growth and the general characteristics of tertiary follicles are summarized. In addition, in vitro culture of tertiary follicles is also discussed as a study model and an assisted reproductive technology model.

• Korean Journal of Organic Agriculture
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• v.25 no.4
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• pp.861-873
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• 2017

The present study was conducted to investigate the developmental characteristics of Propylea japonica Thunberg (Coleoptera : Coccinellidae), a predator of aphids under laboratory conditions. The development times of the egg and immature stages of Propylea japonica were investigated at ten constant temperatures(15, 17.5, 20, 22.5, 25, 27.5, 30, 32.5, 35 and $38{\pm}1^{\circ}C$; 14L:10D; $60{\pm}5%$ RH). Development time was longest at $17.5^{\circ}C$. The developmental periods of P. japonica from the time of egg oviposited to adult emergence was 36.9 days at $17.5^{\circ}C$, and it decreased ash temperature increasing. Threshold temperature of development and degree days of the P. japonica from egg to adult were $11.9^{\circ}C$ and 196.0 respectively. The Briere 2 and Lactin 2 modes were best fitted for all development stages. The distribution of completion of each development stage was explain relatively well that 2-parameter, 3-parameter and Logistic model except egg and pupal stage.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2008.04a
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• pp.297-302
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• 2008

Urbanization has caused population influx into cities, creating housing problems, and housing developmental plans have often resulted in high-rise and high-density housing complexes. Such development have seldom incorporated the environmental factors associated with the complexes and the surroundings, just being busy in increasing the volume of the housing supplies, and as a result, various environmental problems, such as disruption of the air flow, reduction of sunlight exposure amount, and temperature rise, have occurred, deteriorating the living environments. Accordingly, the objectives of this paper are to find out the causes of the problems in the contemporary complex development plans from the urban environmental viewpoint through the investigative analysis of microclimate environment in those complexes, and, further, to present a residential complex planning technique and developmental direction so as to remedy the problems described above. Then a 3-D microclimate model 'Envi-Met' was employed to analyze and predict on the related issues, per the selected planning factors.

• Journal of Gifted/Talented Education
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• v.14 no.3
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• pp.19-40
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• 2004

This paper reports on current work using the Purdue Three-Stage Model to create enrichment classes in science, technology, engineering, and mathematics (the STEM disciplines). First, the history of the Purdue Three-Stage Model and general principles of curriculum and instruction for gifted and talented learners in math/science are reviewed. Then a detailed description of the Model is presented. Following the general description, five specific teacher applications of the Model are presented and compared with respect to the STEM disciplines and developmental levels addressed, and the relative emphasis of each unit on the different stages of the Model. Finally, the advantages of the Model as a framework for curriculum development in science, technology, engineering, and mathematics classes for talented youth are discussed.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.9-19
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• 2003

Pig organ is thought to be the most suitable nonhuman organ for xenotransplanstation. However, one of the major constraints to using pig organs for xenotransplantation is human natural antibody-mediated hyperacute rejection (HAR). Elimination of a(1,3) galactosyltransferase (GGTA1) from the pig is expected to be a solution to the problem of hyperacute rejection. Many efforts have made characterization of GGTA1 in structure and function, improvement in the technique of DNA transfection of somatic cells and advancement of the pig NT, a specific modification has been made to one copy of the GGTAl gene by Missouri group in 2002 To date because homozygousity of the genetic modification has been achieved in this gene, the role of gala(1,3) gal specific natural antibody in HAR and the efficacy of xenotransplantation in a nonhuman primate model will be addressed. Of other genes are found to be involved in rejection of pig donors by primates, the technology will be available to modify those genes so that rejection can be overcome.

• Korean Journal of Child Studies
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• v.31 no.6
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• pp.1-13
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• 2010

This study examined the time-dependent effects of changes in private education on the trajectories of academic achievement among early adolescents. Five-wave data was employed from the KYPS; the participants being 2844 (1524 boys, 1320 girls). All were 4th graders in 2004 and became 8th graders in 2008. Latent growth curve model indicated that academic achievement significantly decreased over the five time points, but there were significant individual differences as well. Participants who reported higher initial levels of academic achievement tended to decrease in academic achievement more slowly over time compared to participants who reported lower levels of initial academic achievement. The effects of private education on academic achievement were at their most powerful when participants were in the 4th grade. Private educational experiences among 6th graders had relatively less influence upon the academic achievement of 7th graders.