• Journal of the Korean earth science society
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• v.29 no.6
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• pp.466-473
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• 2008

This study deals with the morphological characteristics and structure of organ fossils of Neocalamites carrerei such as rhizomes, aerial leafy stems, and cones collected in situ from the Amisan Formation of Nampo Group. Judging from the size of some extant Equisetum and paleoclimate of Daedong flora, it is considered that the size of Neocalamites carrerei was probably very large. The cone of Neocalamites takahashii (Kon'no) is closely associated with the leaves of Neocalamites carrerei. It indicates that two organ fossils mentioned above probably belong to the same species. Comparing with very abundant occurrence of aerial leafy stems and rhizomes in the Amisan Formation, cones are very rare. This fact implies that Neocalamites reproduce not only by spore reproduction, but also by asexual reproduction. Neocalamites largely differ in the leaf form and size from Equisetum.

• 한국지구과학회:학술대회논문집
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• 2004.02a
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• pp.59-59
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• 2004

• Journal for History of Mathematics
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• v.12 no.2
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• pp.63-82
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• 1999

The ways of mathematical meditative concentration of one's attentive calculation are the important records of the mathematics in the Korean mathematical history. Through them, we can find the methods of the mathematical thinking several generations ago, and presume the styles of life in the Chosun dynasty as men see the ancient life by the fossils. Thus we need to see them out of our unconcerns and rearrange them from the disorder without distortions.

• Proceedings of the Korean Quaternary Association Conference
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• 2004.11a
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• pp.44-55
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• 2004

• Journal of the Korean earth science society
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• v.29 no.7
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• pp.531-538
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• 2008

The mode of occurrence of petrified woods from the Tertiary strata of Pohang Basin in Kyeongsangbug-do suggests that the petrified woods are all allochthonous fossils. Petrified woods as well as various types of wood fossils such as carbonized woods and charcoal woods were found. However, some lignified organic remains are rarely found in the bark part of petrified woods. X-ray diffraction analysis showed three types of minerals including Opal-CT, Opal-C, and quartz+cristobalite. The presence of these minerals indicates that silicification occurred under the low temperature. The tuffs are considered to be main source of supply of silica. Analysis of the kind of composing minerals and the condition of tissue preservation can predict that silicification is mainly occurred by replacement.

• Journal of the Korean Magnetic Resonance Society
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• v.6 no.2
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• pp.84-88
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• 2002

Dating and dosimetry using electron spin resonance (ESR) in 20th Century developed at both Yamaguchi University and Osaka University have been reviewed with emphasis on new prospects and strategies in 21th century. Natural radiation have been generating radicals that accumulated in archaeological and geological materials. ESR detects these radicals and the ESR signal intensity is proportional to the radiation dose and therefore the age. The assessment of the total dose of natural radiation and the annual dose rate give their ESR ages. The ESR dating of stalactites and stalagmites ant Akiyoshi cave in Yamaguchi prefecture in 1975 was extended to anthropological dating using bones and tooth enamel excavated in Greek Petralona cave. Fossils of shells and corals gave the ages of marine terraces and sea-level changes. Quartz grains gave the ages of geothermal alteration and fault movements. Future ESR dating of ices at outer planets anf their satellite are also investigated as basic studies for ices od $H_2O,\;CO_2,\;SO_2$ as well as terrestrial hydrates in laboratory. Atomic bomb radiation dosimetry at Hiroshima and Nagasaki using ESR lead to the dosimetry of personnel, Chemobyl and JCO criticality accidents. Monitoring of radiation dose with sensitive materials with tissue equivalence are being developed. finally a new scanning ESR imaging apparatus (a near field microwave microscope) developed in our laboratory gave ESR images of Radicals from fossils to Si-CVD and diamond films as summarized in my book in 2002.

• Journal of Korean Elementary Science Education
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• v.37 no.4
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• pp.416-429
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• 2018

In social constructivist teaching, knowledge construction is achieved through learners' collective social interaction. Vygotsky argued that this process is mediated with language use, and the development of higher order thinking is realized through the transition from inter-personal psychological functions to intra-personal psychological functions. In so doing scientific concepts are internalized to learners. This study examined the third grade elementary students' inter/intra-personal psychological functions and their internalization processes during social constructivist teaching plan about strata and fossils. The lessons were designed along with Wells' dialogic inquiry and Leach and Scott's social constructivist teaching-learning sequences. Results showed that a teacher's utterances of talking with questioning to switch attention, creating cognitive disequilibrium, and expanding the width of students' opinions could make effective inter-personal psychological function. In addition, a learner's inner speech expressed into social discourse through talking about personal experiences, comparing epistemic idea with visual representation, or applying to different situation showed his/her intra-personal psychological function. Some cases of learners' internalization through language use could be at the stage of knowledge building and understanding of the spiral of knowing, but not all. Thus it is argued that a teacher's deeper insight into Vygotskian social constructivist teaching can make elementary science classroom teaching more effective in their inter/intra-psychological functions.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.333-336
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• 2008

During the excavation to find ancient rice seeds from the peat layer (12,500-14,800 bp based on 14 dating samples) of Soro-ri, Cheongwon-gun near Cheongju city, we found not only old rice seeds, but also other organic materials including insect fossil skeletons. Although no complete specimen was found in this study, some body parts were diagnotic enough for identifying species. Among the identified insect fossils, two species were successfully identified based on their characteristic forewing morphologies, e.g., cross-ridges on forewing. The two identified species, Plateumaris sericea and Donacia flemola or near, belong to Donaciinae in Chrysomelidae, and their larvae are known to feed on the root of wetland plants, mainly in Poaceae or Cyperaceae. Such finding proved that a wetland environment was maintained in Soro-ri at that time, and was suitable for such insects to survive. Therefore, evidence from the fossilized rice seeds, together with these insect fossils, clearly proved that the environment at that time was suitable for rice, a common Poaceae species, growing.

• Journal of the Korean earth science society
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• v.41 no.2
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• pp.137-146
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• 2020

A great number of geological research data have been produced by individually conducted researchers and then personally stored in domestic universities and research institutes. However, it is difficult to share data with other researchers owing to low and limited accessibility. The purpose of this study is to systematically establish metadata for inaccessible data, to manage them collectively and to provide opportunities for utilizing the data to those who require efficient research methods. Approximately 1,000 geological specimens (900 rocks and fossils, 100 thin sections) were gathered, along with their metadata such as high-resolution photographs, classification, name, owner, address, and geographical coordinates of the sample site, to establish their features. Additionally, 3D modeling data for 100 rocks and fossils were generated. On the basis of this study, it is possible for researchers to access and share crucial geological data that have a high potential to be lost and have been neglected in restricted spaces; by avoiding the wasted time, energy, and costs caused by repetitive collection of data, researchers may perform effective research and achieve qualified and competitive research results. Moreover, vulnerable and important geological data in the field can be protected from damage caused by indiscriminate, repetitive collection of specimens that have previously been secured. Through the establishment of additional metadata concerning the diversity of rocks, fossils, and thin sections kept at other universities and research institutes, much more data can be recognized, leading to advanced research results. Furthermore, specialized comparison and analysis of basic mineralogy and petrology knowledge are anticipated, based on the use of the metadata.

• Journal of the Korean Society of Earth Science Education
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• v.10 no.1
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• pp.76-89
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• 2017

The purpose of this study is to develop a science field study area using Geumgang(Geum River), fossil origins and various geological resources in Youngdong area of Chungcheongbuk-do as educational resources; and utilize them to develop an education program to cultivate earth science and topophilia. The Youngdong sedimentary basin (Cretaceous period) has a well-developed outcrop along the Geumgang and it is therefore easy to find various geological structures, plant fossils, and dinosaur fossils. Also, it has a distinct sedimentary structure, such as mud cracks, ripple marks and cross-bedding. Science field study area(6 observation sites) were developed based on school curriculum, textbook analysis, and professional earth science education panel discussion to create a convergence education program. The result of validating the developed program showed that all the items were satisfactory ($CVR{\geq}0.88$) in the test categories. The science field study teaching-learning model was applied to actual classes. The evaluation result for class satisfaction was positive, scoring Rickert scale 4.18. The result of observation about the outdoor classroom process in the science field study area revealed that students were able to form a new image of the beautiful scenery of the Geumgang. Also, the students could gain a new understanding, concept and value of various geological objects (sandy beach, stepping-stones, dinosaur footprint fossils, sedimentary formation), which naturally allowed them to form topophilia.