• Asian-Australasian Journal of Animal Sciences
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• v.31 no.7
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• pp.927-932
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• 2018

The demand for beef as a protein source is increasing worldwide, although in most countries beef accounts for considerably less than half of total meat consumption. Beef also provides a highly desirable eating experience in developed countries and, increasingly, in developing countries. The sustainability of beef production has different meanings in the various geographical and socio-economic regions of the world. Natural resources including land mass and uses, rainfall and access to livestock feed, and the robustness of the economy are major determinants of the perception of beef sustainability. In this overview of the 2016 International Symposium on "Future Beef in Asia" and this subsequent Special Edition of the Asian-Australasian Journal of Animal Sciences on "Current Situation and Future Prospects for Global Beef Production", the contributions have been grouped into the following categories: Countries in Southeast Asia; Europe; and Countries producing highly marbled beef for export and/or domestic consumption. They also include reference to Special Topics including marbled beef production, and use of "omics" technologies to enhance beef quality assurance. Among these broad categories, notable differences exist across countries in the production and marketing of beef. These reflect differences in factors including natural resource availability and climate, population size, traditional culture and degree of economic development including industrial and technological developments. We trust that the International Symposium and this Special Edition on Current Situation and Future Prospects for Global Beef Production, the contents of which that are briefly summarized in this paper, will serve as a valuable resource for the livestock industries, researchers and students with an interest in enhancing the prospects for sustainable, efficient beef production that satisfies the growing size and complexity of consumer demands and markets for beef.

• School Mathematics
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• v.19 no.1
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• pp.95-116
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• 2017

Through the teaching experiments, we investigated a series of processes for obtaining the differential coefficient at x=0 of the exponential function $y=2^x$ based on the process of constructing the natural constant e and the understanding of it. and all of the students who participated in this study were students who had no experience of calculating the derivative of the exponential function. The purpose of this study was not to generalize the responses of students but to suggest implications for mathematical concept mapping related to calculus by analyzing various responses of students participating in experiments. It is expected that the accumulation of research data derived in this kind of research on the way of understanding and composition of learners will be an important basic data for presenting the learning model related to calculus.

• Transactions of the Korean hydrogen and new energy society
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• v.14 no.1
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• pp.35-45
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• 2003

Polymer electrolyte fuel cells(PEFC) have been considered to be a suitable candidate for residential, portable and mobile applications, due to their high efficiency and power density, even at low operating temperature. KIER developed a 5kW class PEFC system for residential application and operated the system for over 1,000 hours. To develop a 5kW PEFC system, performance of a cell was improved through successive tests of single cell of small and large area. Fabrication of three 2,5 kW class stacks, design and fabrication of natural gas reformer, design of auxiliary equipments such as DC/DC converter, DC/AC inverter and humidifying units were carried out along with integration of components, operation and evaluation of total system. During the development period from 1999 to 2001, MEA(membrane electrode assembly) fabrication technologies, design and fabrication technologies for separators, stacking technologies and so on were developed, thereby providing basis for developing stacks of higher efficiency and power density in the future. Experience of development of natural gas reformer opened possibilities to use various kinds of fuels. Main results obtained from the development of a 5kW class PEFC system for residential application are summarized.

• Journal of Ginseng Research
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• v.7 no.2
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• pp.172-192
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• 1983

Light environment and growth of Panax ginseng In habitat and cultivation under natural shade were renewed. Grower's experiences on ginseng stand In relation to light environment were assessed. Change of shading method and grower's concepts on light requirement of ginseng plant in Korea, Manchuria and Japan was counted. Growth of wild ginseng was better under rich light. Optimum crown density index appeared to be 0.7 In natural habitat and 0.4 to 0.7 for the cultivation in forest. Change of light Intensity in forest was greatest in May and reached near to constant value (from 40% to 3% for broad leaf deciduous forest and loom 4% to 2% for pine forest). Insufficient light condition induced long and thin stem, poor flowering and seed bearing, and sequent dormancy. Relation between light and ginseng strand was not clear but light Interception with cool weather was effective. Topography and orientation of bed have been deeply considered for light environment. Panel or bark of won were used for shading in deep forest manly In Manchuria while reed blind and straw thatch were used in Korea. Kinds and number of shades material and seasonal or daily schedule have been simplified probably by labor pressure due to eulargement of plantation. Post height has been greater while width of roof, bed and ditch has changed lisle. Scientific survey in the past omitted important light control methods (complete light hardening etc) which has been practiced in specific areas. The concept and technique of light control in the past in Korea were delicate and intensive including the control of temperature and moisture. For the application of old concept in modem cultivation precise Investigation of the technique including the measurement of light, temperature and moisture is needed.

• Korean Institute of Interior Design Journal
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• v.25 no.4
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• pp.51-59
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• 2016

Recent modern architecture shows a lot of cases that introduce natural light in indoor space, arousing diverse emotions within a minimal space by means of changes in the light. There are various causes for the background of these streams of times, and it may be said that pursuing the relationship between natural phenomena and space, using changes in light, is an important factor among them. This is closely linked to the raise of phenomenological architecture. In the case of Japan, there are many cases where the architectural language connected to the traditional architecture has been restructured to fit to modern architectural technique. The modern reinterpretation and development of the Japanese traditional effect of light and its meaning can be seen in cases of Kuma Kengo and Tadao Anndo. Of the modern architects that have used the appearance of spatial concept of light in Japanese architectural space, Kengo Kuma shows his attempt at finding identity in his designs through the acceptance and modern reinterpretation of orientalism of nature, along with the traditional and regional interpretation through materials and ways construction. It is his use oh light input used in traditional Japanese settings that have differentiated his work. On this, the present thesis intends to analyze and synthesize what impressions Kengo Kuma's unique methods of light production create in the formation of users' spatial perception, how the unique encounter of light and materials seems to perceivers, and the characteristics of his light production and expression that harmonize space, human, and nature in the visual and perceptual experience of space;

• Journal of the Korean Institute of Educational Facilities
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• v.27 no.3
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• pp.3-14
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• 2020

The purpose of this study is to discuss the planning direction of educational spaces to support children's healthy and creative learning based on bio_philic theory. This study analyzed the characteristics of the application of biophilic patterns in children's education space through case analysis. The conclusion of this study is summarized as follows. As a result of the analysis of children's classroom space, the pattern of 'A(Visual connection with nature), F(Dynamic & Diffuse Light), K(Prospect)' shows high application rate, but the pattern of 'C(Non-Rhythmic Sensory Stimuli), G(Connection with Natural Systems), I(Material Connection with Nature)' shows low application rate. In particular, there is a lack of connection with patterns such as hearing, smell, touch, taste stimulation and water experience, and curiosity through exploration of nature about 'B(Non-visual connection with nature), E(Presence of Water), N(Risk/Peril)' changes in nature and ecosystem. In the corridor and rest space, the pattern of 'A(Visual connection with nature), D(Thermal & Airflow Variability), F(Dynamic & Diffuse Light), G(Connection with Natural Systems), K(Prospect)' shows high application rate, but 'B(Non-visual connection with nature)' shows low application rate. In addition, the application of patterns related to the stimulation of curiosity through direct exploration of nature and the exploration of the patterns of 'E(Presence of Water), N(Risk/Peril)' is insufficient. Therefore, in the case of classroom spaces, the active use of nature as it is should be considered within the scope that does not cause visual confusion, and it should provide an area that can be experienced through the five senses. And corridors and rest spaces should be designed to introduce more active natural elements as spaces to recover stress caused by learning. In other words, the characteristics of children's education facilities need to be connected between classroom space, corridor, rest space and external space. This study is meaningful in that it analyzes and derives the application characteristics of 'biophilic design' which affects the 'Attention Restoration' of children's educational spaces through foreign cases.

• Journal of Elementary Mathematics Education in Korea
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• v.12 no.1
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• pp.1-25
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• 2008

The purpose of this study was to identify pre-service teachers' Pedagogical Content Knowledge (PCK) about decimal calculation. A written questionnaire was developed dealing with decimal calculation. A total of 152 pre-service teachers from 3 universities were selected for this study; they had taken an elementary mathematics teaching method course and had no teaching experience. The results were as follows: First, with regard to the method of decimal calculation, most pre-service teachers were familiar with algorithms introduced in the textbook. But with regard to the meaning of decimal calculations, they had difficulties in understanding decimal multiplication or decimal division with decimal number. Second, pre-service teachers recognized reasons of errors as well as errors patterns that student might make. But this recognition was limited mainly to errors related to natural number calculation. Third, pre-service teachers frequently commented about decimals algorithms, picture models, the meanings of decimal calculations, and connections to natural number calculations. Many of them represented the meanings of decimal calculations through picture models as to help students' understanding, while they just mentioned algorithms or treated decimal calculation as natural number calculations with decimal point.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.45 no.1
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• pp.34-42
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• 2019

Objectives: Various bone graft substitute materials are used to enhance bone regeneration in the maxillofacial skeleton. In the recent past, synthetic graft materials have been produced using various synthetic and natural calcium precursors. Very recently, eggshell-derived hydroxyapatite (EHA) has been evaluated as a synthetic bone graft substitute. To assess bone regeneration using EHA in cystic and/or apicectomy defects of the jaws through clinical and radiographic evaluations. Materials and Methods: A total of 20 patients were enrolled in the study protocol (CTRI/2014/12/005340) and were followed up at 4, 8, 12, and 24 weeks to assess the amount of osseous fill through digital radiographs/cone-beam computed tomography along with clinical parameters and complications. Wilcoxon matched pairs test, means, percentages and standard deviations were used for the statistical analysis. Results: The sizes of the lesions in the study ranged from 1 to 4 cm and involved one to four teeth. The study showed significant changes in the formation of bone, the merging of material and the surgical site margins from the first week to the first month in all patients (age range, 15-50 years) irrespective of the size of the lesions and the number of teeth involved. Bone formation was statistically significant from the fourth to the eighth week, and the trabecular pattern was observed by the end of 12 weeks with uneventful wound healing. Conclusion: EHA showed enhancement of bone regeneration, and healing was complete by the end of 12 weeks with a trabecular pattern in all patients irrespective of the size of the lesion involved. The study showed enhancement of bone regeneration in the early bone formative stage within 12 weeks after grafting. EHA is cost effective and production is environment friendly with no disease transfer risks. Thus, natural bioceramics will play an important role in the reduction of costs involved in grafting and reconstruction.

• Korean Journal of Environment and Ecology
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• v.33 no.4
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• pp.462-471
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• 2019

The purpose of this study is to analyze the difference between local residents and tourist groups in the relationship between the motivation for visiting and the satisfaction of Chung Nam Dae which is the leading tourist attraction in the Chungbuk region. We obtained 200 validated samples each of the local residents in Chungcheongbuk-do Province and the tourists from outside of Chungcheongbuk-do Province with experience of visiting Cheongnamdae through the survey using the questionnaire organized through literature research. The analysis result showed that the relationship between motivation and satisfaction varied depending on the overall sample, local residents, and tourist and that the natural relaxation and convenience had a positive impact on satisfaction in all groups. There was a difference in the influence between motivation and satisfaction between the two groups. Four motivational factors, including natural relaxation, convenience, historicity, and relationship had the significant influence on satisfaction for the local residents while two motivational factors, including natural relaxation and convenience, had the significant influence on satisfaction for the tourists. Based on the results of the study, we presented the theoretical and practical implications and suggested follow-up studies.

• (The)Study of the Eastern Classic
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• no.33
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• pp.7-29
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• 2008

Jang, Hyeon-Guang is one of the representative natural philosophers of Joseon Korea. This article aims to investigate the meaning of the factors of Xiangshuxue(象數學) contained in his cosmology. Xiangshuxue applies Image(Xiang), Numeral(Shu) and In-Yang to present the distinctions, inter-relations and time-series orders of things. Jang's cosmology, combined with Xiangshuxue, insisted that Li(Principle) is infinite in time and space, the cosmos is finite on the other side. This assures that the moral principle is absolute and eternal. Jang emphasized the book I-ching as the criterion and the model in understanding the nature. This restrained the objectivizm of Shaoyong and made his concept 'natural law' difficult to change itself as the experience and the knowledge expand. None the less, his cosmology is appraised in that it strengthened natural philosophical basis of neo-confucianism and preceded the cosmological investigations since mid-Joseon dynasty.