• The korean journal of orthodontics
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• v.28 no.3 s.68
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• pp.441-452
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• 1998

The c-fos is known as neuronal marker of second neurons which is activated by noxious peripheral stimulation. To investigate the changes of c-fos el(pression in the trigeminal nucleus complex during tooth movement, immunohistochemical study was performed. Experimental rats(9 weeks old, 210 gm 21 rats) were divided into seven groups(normal, 1 hour group, 3 hour group, 6 hour group, 12 hour group, 1 day group,3 day group). Rats in the normal group were anesthesized without orthodontic force. Rats in the experimental groups were applied orthodontic force (approximately 30 gm) to upper right maxillary molar. Frozen sections of brain stem were immunostained using rabbit antisera. The changes of c-fos expression were observed with respect to rostrocaudal distribution, laminar organization, md duration of orthodontic force application. The study results were as follows $\cdot$The c-fos nuclei in the dorsal part were observed from ipsilateral transition zone of subnucleus interpolaris and subnucleus caudalis to $C_1$ cervical dorsal horn rostrocaudally. The maximal peak point was the rostral part of subnucleus caudalis. The greatest proportion of c-fos cells were located within lamina I and II. $\cdot$The c-fos nuclei in the dorsal Part were observed from the most caudal part of subnucleus interpolaris to the middle part of the subnucleus caudalis. $\cdot$The number of c-fos immunoreactive dot increased at 1 hour group, reached its maximum at the 3 and 6 hour groups, and showed a decreasing trend after 12 hours. These results imply that nociceptive stimulation caused by continuous orthodontic force might be modulated by transition zone of subnucleus interpolaris and subnucleus caudalis, subnucleus caudalis, $C_1$ spinal dorsal hem.

• Journal of The Korean Association For Science Education
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• v.29 no.1
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• pp.116-136
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• 2009

Since there are differences in the content, structure and functions of interpersonal communication during the practice of school science classes, it needs to articulate the difference of the modality of pedagogical practice in order to understand science teaching in detail. These characteristics of science teaching can be investigated by further insightful analysis on language in the science classroom. In this study, classroom discourse language codes using Bernstein's code theory were analyzed in the case of a middle school science class on the unit of minerals. The discourse language code was identified by the value of classification, which revealed power relations to the contexts of discourse and participants of discourse. It was also identified by the value of framing, which showed hierarchical relation between teacher and students as discourse subjects, and discursive control on the initiative of discourse. The results addressed that six types of discourse language codes were constructed and that those language codes reflected diverse modalities of science teaching from student-centered instruction to teacher-centered instruction in relation to classroom discourse. The modality of science teaching according to the transition tendencies of discourse language code showed dynamic variations of 'controlled student-centeredness inducing teaching' - 'positional student-centeredness permissive teaching' - 'controlled students' participation permissive teaching' - 'controlled student-centeredness facilitative teaching' - 'student-centeredness enhancing teaching'. In addition, results released that discursively and hierarchically weak control of discourse is necessary for enhancing student-centeredness of science teaching. Moreover, teaching practice enhancing student-centeredness can be accomplished by the harmony of a teacher's perception of discourse language code and his/her orientation to constructivist teaching and student-centered teaching.

• Korean Journal of Environment and Ecology
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• v.24 no.2
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• pp.117-129
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• 2010

The vascular plants of the 15 sites of Taeanhaean National Park were identified as 493 taxa; 117 families, 326 genera, 436 species, 49 varieties, 6 form, 2 hybrids. The National Park area includes coastal areas and islands, these islands reflects well the floristic characteristics of coastal area and transition area of the middle province and the southern province. The study revealed that Ficus erecta Thunb., Machilus thunbergii S. et Z., Neolitsea sericea (Bl.) Koidz. and Eurya japonica Thunb. etc. were the mainly distributed species in the southern area while Rosa rugosa Thunb., Carex kobomugi Ohwi and Elymus mollis Trin., etc. were mainly distributed species over the coastal dune area. Deciduous and evergreens broad-leaved trees like Acer palmatum Thunb. ex. Murray, Euonymus japonica Thunb. and Camellia japonica L., etc. were all together distributed in Taeanhaean National Park. There are no any Endangered species designated by The Ministry of Environment were not found. The floristic special plants were recorded to a total of 53 taxa; that is, class I species (41 taxa) were containing as Vitex rotundifolia L. Fil., Arisaema heterophyllum Bl. and Arisaema ringins (Thunb.) Schott, etc, class II species (1 taxon) were Iris ensata var. spontanea (Makino) Nakai, class III species (7 taxa) were containing; Koelreuteria paniculata Laxm., Salsola collina Pall. and Daphniphyllum macropodum Miq., etc, class IV species (1 taxon) were Angelica japonica A. Gray, class V species (1 taxon) were Utricularia vulgaris var. japonica (Makino) Tamura. The naturalized plants were identified a total of 52 taxa; 17 families, 44 genera, 51 species, 1 form; Solanum carolinense L., Phytolacca americana L. and Oenothera odorata Jacq., etc. Among them the ecosystem disturbance wild animals·plants was identified as Solanum carolinense L. Hypochoeris radicata L. and Solidago altissima L. The study suggests that these areas require management such as physical remove of this ecosystem disturbance field plants.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.4
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• pp.1-13
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• 2014

As part of reconsideration on naming of the scenic site No.1 "Myeongju Cheonghak-dong Sogumgang," this study attempts to identify whether there is any mistake with reference to place naming of Korea's No.1 scenic site and if so, to correct the problem by examining the origin of the name and its transition progress through analysis and interpretation of old maps, ancient documents such as traditional geographic books, Yusangi(遊山記) and Letters Carved on the Rocks. The findings of this study are as follows: In traditional geographic books, a term of 'Mt. Cheonghak(靑鶴山)' was first found from "SinjungDonggookyeojisungram(新增東國輿地勝覽)" and after a place name, 'Sogumgang(小金剛)' first appeared in "Yeojidoseo(輿地圖書)" in the middle of the 17th century, it was reproduced in "Jungsuimyeongji(增修臨瀛誌)", which was published in the early 20th century. However, as a result of analyzing old maps, the place name, Sogumgang cannot be found in any local or national map except place names such as Cheonghak-dong, Mt. Cheonghak and Temple Cheonghak. Even though 'Biseonam,' 'Cheonyudong,' 'Gyeongdam' and 'Mt. Cheonghak' appear in Yulgok's "Yucheonghaksangi(遊靑鶴山記)", any part in which 'Sogumgang' was referred is not found. Later, Cheonghak-dong Sogumgang seemed to had been called 'Mt. Cheonghak' or 'Cheonghak-dong(靑鶴洞)' for more than three centuries as seen in Lee Sun-il's "Godamilgo(孤潭逸稿)", Heo Geun's farewell records, Heo Mok's "Cheonghak-dong Guryongyeongi(靑鶴洞九龍淵記)", Yoon Sun-geo(尹宣擧)'s "Padongilgi(巴東日記)" and Lee Won-jo's letters and a poem composed by Gang Jae-hang in the middle of the 18th century is the only record in which the place name, 'Sogumgang' is shown. Meanwhile, 'Sogumgang' carved on Inung Rock(二能巖) in front of Temple Gumgang is presumed to be carved by Inunggyeoone(二能契員) in the 1870s or in 1930s, considering the size of each character, calligraphy, overall layout, wear extent and records in Jiriji. Therefore, no evidence can be found to say that each character of 'Sogumgang' was written by Yulgok because 'Sogumgang' has strong evidences of the origin of its place name. To sum up the findings stated above, since Yulgok's "Yucheonghaksangi", this place seems to have been referred as 'Mt. Cheonghak Cheonghak-dong' and as it is confirmed that the place name, 'Sogumgang' first appeared in "Ohyeongosijo(五言古時調)" of "Ibjaeseonsangyugo(立齋先生遺稿)" and "Yeojidoseo" in the middle of the 18th century, it can be inferred that the place name, Sogumgang had been partly mingled as an another name of Mt. Cheonghak. Therefore, even though it is difficult to say the existing place name has a significant problem, it is thought that it will be better to name 'Mt. Cheonghak Cheonghak-dong' rather than 'Cheonghak-dong Sogumgang' in order to stress on this place's traditional identity as a scenic site related to Yulgok. In addition, as confirmed in this study process, it is said that each character of place names, 'Mt. Cheonghak' and 'Gyeongdam(鏡潭)' and name 'Yoon Sun-geo' carved in Rock Sikdang stated in Yoon Sun-geo's "Padongilgi" in 1964 is a pledge showing the influence of "Yucheonghaksangi" as an ancient travel literature as well as a mark of the Giho school scholars' respect and spirit to honor Yulgok.

• Korean Journal of Materials Research
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• v.21 no.5
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• pp.250-254
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• 2011

We have synthesized bluish-green, highly-efficient $BaSi_2O_2N_2:Eu^{2+}$ and $(Ba,Sr)Si_2O_2N_2:Eu^{2+}$ phosphors through a conventional solid state reaction method using metal carbonate, $Si_3N_4$, and $Eu_2O_3$ as raw materials. The X-ray diffraction (XRD) pattern of these phosphors revealed that a $BaSi_2O_2N_2$ single phase was obtained. The excitation and emission spectra showed typical broadband excitation and emission resulting from the 5d to 4f transition of $Eu^{2+}$. These phosphors absorb blue light at around 450 nm and emit bluish-green luminescence, with a peak wavelength at around 495 nm. From the results of an experiment involving Eu concentration quenching, the relative PL intensity was reduced dramatically for Eu = 0.033. A small substitution of Sr in place of Ba increased the relative emission intensity of the phosphor. We prepared several white LEDs through a combination of $BaSi_2O_2N_2:Eu^{2+}$, YAG:$Ce^{3+}$, and silicone resin with a blue InGaN-based LED. In the case of only the YAG:$Ce^{3+}$-converted LED, the color rendering index was 73.4 and the efficiency was 127 lm/W. In contrast, in the YAG:$Ce^{3+}$ and $BaSi_2O_2N_2:Eu^{2+}$-converted LED, two distinct emission bands from InGaN (450 nm) and the two phosphors (475-750 nm) are observed, and combine to give a spectrum that appears white to the naked eye. The range of the color rendering index and the efficiency were 79.7-81.2 and 117-128 lm/W, respectively. The increased values of the color rendering index indicate that the two phosphor-converted LEDs have improved bluish-green emission compared to the YAG:Ce-converted LED. As such, the $BaSi_2O_2N_2:Eu^{2+}$ phosphor is applicable to white high-rendered LEDs for solid state lighting.

• Journal of The Korean Association For Science Education
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• v.19 no.2
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• pp.256-265
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• 1999

The purpose of this study is to investigate the relationship between cognitive levels and achievement of science process skills. A science laboratory process skills test based on optional instrument of the SISS was administered to a sample of 162 students in the 8th grade. Practical assessment tasks consisted of the contents about acid, base, density, and a property of cobalt chloride. The format of this practical test was the station type that students had to conduct a short activity. Science process skills included three sub-skills which were categorized as designing, performing, and reasoning. As cognitive levels develop from concrete operational stage to transition stage and formal operational stage. total scores of science process skills and mean scores of sub-skills were significantly increased. Regardless of cognitive levels. all students were more successful on performing than designing or reasoning. In case of being controlled cognitive levels, gender differences and area differences were not detected in achievement of science process skills. According to these results. there was a strong relationship between cognitive levels and achievement of science process skills by practical assessment. This study implies that considering student's cognitive levels is very important for improving science process skills.

• Journal of Elementary Mathematics Education in Korea
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• v.17 no.1
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• pp.105-128
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• 2013

One of the biggest changes in 2007 Curriculum Revision is introduction of letter, equation, direct proportion and inverse proportion in fifth and sixth grade of mathematics. The purpose of this study is to provide some implications about teaching-learning method for introduction of letters, teaching and learning activities of equation between the 6th Curriculum and 2007 Curriculum Revision. The below conclusions were drawn from findings obtained in this study. First, the letter and expression were learned in fifth and sixth grade until 6th Curriculum and were learned in seventh grade in middle school of 7th Curriculum. But letter, equation are introduced in 2007 Curriculum Revision again. The overall contents of letter and expression were learned on the 'Relationship' domain in the 6th Curriculum, it were learned on the 'Letter and expression' domain in the 7th Curriculum and is learned on the 'Regularity and problem-solving' domain in the 2007 Curriculum Revision. Second, teaching method of these contents was to promise some definitions at first and then to solve exercises in the 6th Curriculum. But leaning was forced to improve student's problem-solving in the 7th Curriculum. To reduce student's pressure offers at a minimum mathematics terms and to provide problem situations to students who contact daily, it is emphasized on learner's communication in the 2007 Curriculum Revision. We want to be easily connected elementary mathematics and higher mathematics through this study about letter, equation. We recognized how we teach the letter and expression to reduce misconceptions and draw a transition from arithmetic thinking to algebraic thinking and want to be continue of another studies.

• The Journal of the Korea Contents Association
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• v.15 no.5
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• pp.651-660
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• 2015

This study was conducted to consider application methods of infographic that corresponds to the educational goals of English subject, which is applied with different teaching and learning standards than other subjects. The aim of this study is to analyze the types and the characteristics of 'infographic completed by know-how learning', in other words, 'User behaviors involved infographic', which is frequently used in English textbook. Based on an analysis according to the teaching and learning standards, infographic used in English textbook were suggested in three types, which are 'General Concept', 'Significance' and 'Signification' centered infographic. In addition, according to the level of diagram composition, the main visualization attributes were derived as 'Overview', 'Structure', 'Relationships', 'Sequence', 'Transition between states' and 'Messages'. The major findings of this study are as follows: First, it is necessary to conduct a study on diverse display methods for 'Signification-centered infographic' that need to be displayed on the basis of two or more visual attributes. Second, as the purpose of application for applying infographic in English textbook collides with that in information design fields, it is found that verification is required on the educational effects in relation to this aspect.

• 대한공업교육학회지
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• v.45 no.2
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• pp.21-45
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• 2020

The purpose of this study was to verify how the vocational education for training industrial workforce as a national human resource development (NHRD) system has undergone a transition process in relation to the national economic, industrial, and socio-cultural contexts. First, how vocational education as an industrial workforce training system has changed in accordance with Korea's economic environment, industrial development, and social changes; second, what are the main factors that influenced the role and importance of vocational education; and third, vocational education as a system for training industrial workforce and training workforce in science and engineering were analyzed differently from the perspective of the NHRD model. To this end, domestic and international academic journal papers, research reports, and thesis were investigated and classified by period, and major changes in vocational education were analyzed in relation to economic, industrial, and social issues and policies by period. As a result of the research, first, as the industry advanced, the level of vocational education increased and the scope expanded. Second, vocational education tended to shrink gradually after the manufacturing industry base, and especially secondary vocational education tended to decline after the national industry focused on light industry. Third, since the 1970s, the diversification of the NHRD and jobs has resulted in wage gaps depending on the level of education, which has increased the preference for university education and avoided secondary vocational education. In addition, a NHRD model focusing on training science and engineering workforce was proposed to compare the existing NHRD model focusing on overall vocational education, and it was revealed that the NHRD needs to be subdivided into various fields or levels to derive a model and examine changes. From the results of the study, vocational education in Korea, especially in secondary vocational education, has declined due to large impacts on socio-cultural perception due to economic growth, enthusiasm for education, and external shocks such as the financial crisis, and the long-term effort to change this perception is suggested to overcome the crisis of vocational education.

• Journal of Nutrition and Health
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• v.41 no.6
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• pp.561-572
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• 2008

Currently, Korea is facing dramatic nutrition transition among children, which may increase risk of degenerative diseases due to excessive intakes of fats, sugars and sodium. Promotion of eating healthier foods among children is difficult because the present nutrition label is not easily understood. Therefore, to promote healthier foods this study was aimed at developing guidance of standard amounts of high, medium and low levels of sugars, sodium, fats and other components contained in foods or drinks that are promoted to or formulated for consumption by children. Multipronged approach was used to collecting information, including key word searches in Medline and other databases, internet searches, reports from world organization, and contact of key individuals who work in organizations. We reviewed dietary reference intakes for Koreans, nutrient reference values, nutrient content claims of nutrition labeling, guideline daily amounts of United Kingdom, dietary guidelines and consumption data of nutrients, and selected components for labeling. And we decided goals of guideline daily amounts for children and nutrient criteria to underpin the high, medium and low content of each component. Then we collected data on processed foods sold at 12 middle schools and 11 high schools in Seoul, and classified processed foods into food category. Sales per one student per day were in the order of snacks, breads, and non-carbonated drinks. One hundred forty five mostly consumed products were selected and classified into criteria of high, medium and low total fat or sodium. Eighty five(58.6%) were classified into high fat food and only 11(7.6%) into high sodium food, in case that the base is chosen per 100 g or 100 mL. In conclusion, the nutrient criteria and choice of 100 g base, which we suggest in this study, need to be tested by simulation with more processed foods and refined in view of the practical issues suggested by stakeholders in future.