• Journal of the Korean Society of Earth Science Education
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• v.15 no.2
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• pp.299-309
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• 2022

The purpose of this study is to categorize specific factors and characteristics of positive science experience by qualitatively analyzing the positive science experience cases in the memories of pre-service elementary school teachers. For this purpose, 101 essays written by pre-service teachers on the theme of 'my enjoyable science class experience' were analyzed. The collected data were analyzed using an inductive analysis method, and as a result, the characteristics of positive science experience cases in the memories of pre-service teachers were categorized into 4 categories and 12 topic groups. Specifically, 'experience of exploratory activities using special materials', such as long-term raising and observation of animals and plants, experiments using edible materials, and using special experimental tools had a positive effect on scientific experience. In addition, 'experience of activities emphasizing scientific inquiry' such as emphasizing observation activities, experiments accompanied by clear experimental results, making activities, and using various materials also had a positive effect on science experience. In addition, 'student-centered activity experience' such as strengthening student autonomy, emphasizing collaboration between students, and performing science activities outside of the curriculum also had a positive influence on the science experience. Lastly, 'positive influence of teachers', such as teachers' encouragement and enthusiasm, helped to positively recognize science.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.3
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• pp.391-397
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• 1995

This study was carried out to investigate the characteristics of the seedling growth and nutrients uptake at 45 day seedlings in cytoplasmic genetic male sterile lines(HR7028A, IR54756A), their restore line (Yongmoonbyeo) and check variety (Changsungbyeo). Hybrid rices had longer and more roots, heavier dry weight and lower shoot /root ratio than their parents and inbred check variety, showing heterobeltiosis in absorbed amount of inorganic elements, content of total sugar, starch and chlorophyll in plant. Different magnitude of heterobeltiosis were shown between F$_1$ hybrid rices with the same restore line; HR7028A/Yongmoonbyeo had higher heterobeltiosis than IR54756A/Yongmoonbyeo did. Hybrid rices had more number and higher $\alpha$-naphthylamine oxidizing ability of newly-grown roots in 10 day sand culture in ground water with root-cut 45 day-seedling than parental lines and inbred variety. Nunber of the newly-grown roots were positively and significantly correlated with content of total sugar, starch and absorbed amount of inorganic elements in the shoot, and content of chlorophyll in the leaf.

• Journal of Ginseng Culture
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• v.5
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• pp.97-114
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• 2023

Despite numerous studies, research on ginseng in aspect of an economic and business perspective are insufficient. Recently, research to reveal the economic cause of ginseng products purchase is drawing attention. The purpose of this study is to analyze empirically the factors of ginseng products purchase by international consumers from a microeconomic perspective. Using the survey data, we empirically investigate the determinants of ginseng products purchase by international consumers visiting Korea. We use a multinomial logistic model to find the determinants that influence the purchase of ginseng products. This study finds the followings. First, the economic factor is an important determinant of ginseng products purchase. The average daily expenditure has a greater impact on ginseng products purchase than household income does. Even though the average daily expenditure is high, they tend to buy less ginseng products when they prefer other products. Second, demographically, gender and age are also important determinants of ginseng products purchase. It has been found that elderly male consumers are more likely to buy ginseng products. Third, international consumers for leisure purposes have a higher probability of buying ginseng products than tourism consumers for other purposes do. Finally, destination attributes such as security (safety), ease of use of mobile/Internet, and ease of finding directions are also important factors affecting ginseng products purchase. In addition, it is found that the convenience of using the mobile/Internet, the ease of finding directions, and the convenience of shopping increase the probability of buying ginseng products by international consumers. This study is meaningful in that it explored the determinants of ginseng products purchase by analyzing individual consumers' ginseng products choices.

• Journal of the Korean Society of Earth Science Education
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• v.16 no.1
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• pp.30-42
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• 2023

The purpose of this study is to quantitatively and qualitatively analyze the science journals written by pre-service elementary school teachers, and to categorize the view on the nature of science and the process of their change. For this purpose, 112 science journals written by 13 pre-service elementary school teachers were analyzed. The frequency of each area was analyzed using the research framework of the four areas of the nature of science, and the pattern of change in perspective on the nature of science was inductively derived and classified using the VNOS-C test analysis framework. As a result, The nature of scientific thinking, nature of scientific knowledge, nature of STS, and nature of scientific inquiry were described in relatively similar proportions, but among them, The nature of scientific thinking appeared in the largest percentage, and the nature of scientific inquiry was described in the smallest percentage. The variability of scientific knowledge, the importance of empirical evidence, and the positive and negative effects of science were especially intensively addressed. In addition, the changing aspects of pre-service elementary school teachers' perspectives on the nature of science could be categorized into 'naive view maintenance type', 'informed view maintenance type', 'regression type', 'development type', and 'mixed type'. The element of 'the empirical nature of scientific knowledge' showed various patterns of change depending on the students, and most of the students maintained a informed view on the tentativeness of scientific knowledge for several sessions.

• Journal of the Korean Society of Earth Science Education
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• v.16 no.1
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• pp.72-86
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• 2023

The purpose of this study is to examine what epistemological beliefs pre-service teachers have about science depending on the situation, and to explore in-depth changes in epistemological beliefs through disciplinary reading. For this purpose, 77 essays written by pre-service elementary school teachers after reading Feynman's 'the meaning of it all' were analyzed using an inductive analysis method. As a result of the study, the epistemological beliefs of pre-service teachers were divided into two situations: 'science in subject learning' and 'science in daily life', and the epistemological beliefs formed in the 'science handled by scientists' situation were analyzed after reading the book. Each situation was divided into sub-categories of 'Impression of Knowledge', 'Source of Knowledge', 'Justification of Knowledge', 'Variability of Knowledge', 'Structure of Knowledge', and 'Value of Knowledge Acquisition' to reveal differences in sophisticated beliefs and naive belief levels. As a result, it was derived that Feynman's science lecture influenced pre-service teachers in terms of establishing new perspectives and recontextualizing existing epistemological beliefs. This study is meaningful in that pre-service teachers' scientific epistemological beliefs may vary depending on the situation, and that the scope and depth of epistemological beliefs may be expanded to include scientists' beliefs in science through disciplinary reading.

• Journal of the Korean Society of Earth Science Education
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• v.16 no.2
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• pp.276-290
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• 2023

The purpose of this study is to analyze the characteristics and specific elements of successful science classes that pre-service elementary school teachers think. For the study, 61 pre-service elementary school teachers (47 females, 14 males) were recruited as research participants. The data used in the study are mutual evaluation papers prepared during class performances by group and individual. The amount of data was a vast amount of qualitative data with a total of 150 pages, and the research results were derived by inductively categorizing this data through qualitative analysis. The summary of the research results is as follows. First, the factors constituting a successful science class were analyzed into 7 categories (14 sub-categories, 33 sub-elements). The elements that make up a successful science class in detail were analyzed as science subject contents, class management, selection of teaching and learning methods and organization of class contents, teaching and learning materials, understanding of students, understanding of teaching situations, and class-related efforts. Second, it was possible to describe the practical classes of pre-service teachers by collecting the details of the elements that make up a successful science class recognized by pre-service teachers. As seen in the above research results, the characteristics and specific elements of successful science classes recognized by pre-service teachers were identified, and based on this, pre-service teachers will be able to develop support for effective science class operation, and continuous analysis should be conducted.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.4
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• pp.603-613
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• 2017

The purpose of this study was to develop an scientific inquiry learning module by applying ESD and to verify its effect so that students could understand sustainable development and geology concepts by reconstructing the contents of the geology related unit. For this purpose, the "Volcanoes and Earthquakes" unit in the 3-4 grade group of the Korea national curriculum was selected and the scientific inquiry learning module was developed. The developed inquiry learning module consisted of one textbook and one teacher 's guidebook, and it was put into one class of elementary school to verify the effect. As a result, the teacher said that it was good to be taught contents of ESD and it was useful because of the concreteness of inquiry activities. The students responded that they were interesting because developed textbook is more often the interesting picture and activity than traditional textbook. And the students responded that 'ESD' has been an opportunity to be interested in science.

• Journal of Korean Society of Forest Science
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• v.51 no.1
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• pp.1-21
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• 1981

Populus glandulosa and Populus tomentiglandulosa, which were known to be natural hybrids, were examined for morphological, physiological and karyological traits to illucidate its hybridity and taxonomical importance. The results abtained were as follows; 1. Survival rate in rooting of cuttings and grafting was different between the hybrids and their rooting abilities showed incomplete dominance. 2. Their leaf openings showed incomplete dominance. The leaf longevities of P. alba ${\times}$ glandulosa and P. tomentiglandulosa were stronger than the other hybrids. 3. There were differences in resistance to toxicity of $KClO_3$ between the hybrids. 4. Many external leaf characters of the hybrids also showed incomplete dominance. P. tomentiglandulosa was similar in those characters to P. alba ${\times}$ glandulosa while P. glandulosa was similar to hybrids crossed, reciprocally crossed or back-crossed between P. davidiana and P. alba. 5. Their numbers of male flower showed incomplete dominance or hybrid vigor. The numbers of P. tomentiglandulosa were similar to thosa of P. alba ${\times}$ glandulosa while those of P. glandulosa to those of P. alba ${\times}$ davidiana or P. davidiana ${\times}$ alba. 6. Morphology and band color of male catkin bract showed incomplete dominance. Those of P. glandulosa were similar to those of P. alba ${\times}$ davidiana while those of P. tomentiglandulosa to those of. P. alba ${\times}$ glandulosa. 7. There were differences in vascular bundle number and arrangement of petiole between the hybrids. 8. Differences in the anatomical traits of stem did not exist between the hybrids but those in wood fiber size existed. 9. The chromosomes of artificial hybrids, P. glandulosa and P. tomentiglandulosa showed irregular behavior in metaphase I and II. 10. All hybrids including P. glandulosa and P. tomentiglandulosa showed small number of P.M.C. with 19 II but many univalent chromosomes were exhibited in metaphase I. 11. All hybrids including P. glandulosa and P. tomentiglandulosa showed a little abnormal nuclear plates as laggard chromosome and chromosome bridge in anaphase I and II. 12. The frequency of pollen tetrad and fertile pollen was low in most of the hybrids including P. glandulosa and P. tomentiglandulosa.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.4
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• pp.265-272
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• 2002

Forage breeding laboratory of National Livestock Research Institute, R.D.A. has made interspecific hybrids of Lolium multiflorum $\times$ L. pratensis and intergeneric hybrids of Lolium $\times$ Festuca since 1984, and has collected ecotypes of Italian ryegrass since 1991. Growth characteristics of these hybrids and ecotypes were researched, and then these clone lines were named. Among these clone lines, the several clones that have polen fertility, high cold-tolerance, and similar heading time were used for making synthetics, Naehan 6, 7, 8, 9, with polycrossing method in 1997. Field experiments were carried out to compare the mophological and agronomical characteristics and forage productivity and quality of the synthetics with those of Italian ryegrass varieties, Barmultra and Hwasan 101. in Suwon and Yonchun from 1999 to 2000. Heading time of the synthetics were 22th to 24th May that belong to late-mature types to be similar to that of Barmultra and Hwasan 101 in Suwon. The synthetics were 101 to 106 c3n in plant length, medium or thick in thickness of stem, dark peen in leaf color, broad and long in flag leaf, strong in lodging resistance, and excellent in regrowth. Winter survivals of the synthetics were no different from that of Barmultra or Hwasan 101 in Suwon, but better than that of Barmultra or Hwasan 101 in Yonchun where was -10 to -12$^{\circ}C$ of minimum average air temperature in January or February. Dry matter(DM) yields of the synthetics were similar to DM 8,238kg per ha of Barmultra in Suwon, but in Yonchun, were more 7 to 13% than DM 7,291kg per ha of Barmultra. Forage qualities, IVDMD, ADF, NDF and TDN of the synthetics were lower than those of Hwasan 101, but higher than those of Barmultra.

• Journal of the Korean earth science society
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• v.34 no.4
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• pp.313-328
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• 2013

Jurassic granitoids in the northeastern part of the Yeongnam Massif are possibly the result of intensive magmatic activities that occurred in response to subduction of the proto-Pacific plate beneath the northeast portion of the Eurasian plate. Geochemical studies on the granitic rocks are carried out in order to constrain the petrogenesis of the granitic magma and to establish the paleotectonic environment of the area. Whole rock chemical data of the Uljin granitoids in the northeastern part of the Yeongnam Massif indicate that all of the rocks have the characteristics of calcalkaline series in subalkaline field. The overall major element trends show systematic variations in each granitic body, but the source materials of each granitoids seem to have different chemical composition. The Uljin granitoids are different from other granitic rocks, which distributed vicinity of the study area, in the contents of $Al_2O_3$ and trace elements such as Cr, Co, Ni, Sr, Y and Nb. The Uljin granitoids have geochemical features similar to slab-derived adakites such as high $Al_2O_3$, Sr contents and high Sr/Y, La/Yb ratios, but they have low Y and Yb contents. The major ($SiO_2$, $Al_2O_3$, MgO) and trace element (Sr, Y, La, Yb) contents of the Uljin granitoids fall well within the adakitic field. The Uljin granitoids have similar geochemical characteristics, paleotectonic environments and intrusion ages to those of the Yatsuo plutonic rocks of Hida belt located on northwestern part of Japan. Chondrite normalized REE patterns show generally enriched LREEs ($(La/Yb)_{CN}=10.6-103.4$) and are slight negative to flat Eu anomalies. On the ANK vs. A/CNK and tectonic discrimination diagrams, parental magma type of the granites corresponds to I-type and volcanic arc granite (VAG). Interpretations of the chemical characteristics of the granitic rocks favor their emplacement in a compressional tectonic regime at the continental margin during the subduction of Izanagi plate in Jurassic period.