• Proceedings of the Korea Society for Industrial Systems Conference
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• 2001.05a
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• pp.224-231
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• 2001

Hydrogenated amorphous carbon films were deposited by ERC-PECVD with deposition conditions, such as ECR power, gas composition of methane and hydrogen, deposition time, and substrate bias voltage. The characteristics of the film were analyzed using the AES, ERDA, FTIR. Raman spectroscopy and micro hardness tester. From the results of AES and ERDA, the elements in the deposited film were confirmed as carbon and hydrogen atoms. FTIR spectroscopy analysis shows that the atomic bonding structure of a-C:H film consisted of sp³and sp²bonding, most of which is composed of sp³bonding. The structure of the a-C:H films changed from CH₃bonding to CH₂or CH bonding as deposition time increased. We also found that the amount of dehydrogenation in a-C:H films was increased as the bias voltage increased. Raman scattering analysis shows that integrated intensity ratio (I/sub D//I/sub G/) of the D and G peak was increased as the substrate bias voltage increased, and films hardness was increased.

• 한국문화재보존과학회:학술대회논문집
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• 2004.10a
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• pp.55-65
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• 2004

We have used the Naju Oryang-dong Kiln, the Jar coffin producing center from the 5th to early 6th century A.D. found for the first time in Korea in 2002 and conducted trace element analysis of Jar coffin objects excavated in Jar coffin the old tomb area formed mainly around Yeongsan valley, the consuming area of the same period as our main research objects. For this analysis, we have used both the NAA method, the non-parametric micro-minerals analysis. In order to compare and verify these remains, we have used the results from the analysis on the Jar coffin remains in the Mandong remains, Jeonbuk district. We have quantitatively analyzed 17 types of elements from the Jar coffin remains sample to allow for various and correct analysis. With their results, we could find out that the jar coffins made in Oryang-dong kiln teo are statistically identical to those in Daean-ri Old tomb/Shinchon-ri 9th old tomb, Okya-ri old tomb, and Banam-Old tomb. Also, we can conclude that there is a high possibility that ongwans produced from Oryang-dong kiln being used in Daean-ri Old tomb/Shinchon-ri 9th old tomb, Okya-ri old tomb, and Banam-Old tomb was distributed through some form of trade. On the other hand, we could obtain other analysis results that jar coffins excavated and investigated in the Mandong remains and Ithe npyong Old tomb were likely from other Jar coffin kilns through trade and distribution.

• 한국문화재보존과학회:학술대회논문집
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• 2004.10a
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• pp.137-153
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• 2004

We have analyzed the ingredients of 17 pieces of Bronze Age bronze ware, and an additional 22 pieces of Koryo and Chosun dynasty bronze ware. We have also conducted analysis of the extraction sites where these bronze ware items were found. For analyzing the main ingredient the bronze ware items have been divided into 3 groups - Cu-Sn(70?75:20), Cu-Pb-Sn(70:10:10), Cu-Pb-Sn(60:10:20) type respectively. In tile cases of the Cu-Pb-Sn groups the division comes down to differences in the Cu content as the main component, and elements such as Ni, Fe, Co contribute as a micro ingredient. The geographical and periodic characteristics of ancient bronze ware items show that theircompositional element changes from Cu:Sn to Cu:Pb:Sn and the Cu content decreases with the period,while the Pb content increases with the period. Bronze ware items from Suchon Ri, Gongju (that were used in 3 B.C.) form very different categories from 3rd ${\~}$ 2nd B.C.. They additionally formed very different categories from those bronze ware items analyzed in this research. These bronze ware itemsare shown to be geographically close and periodically overlapped, but made of a new elemental composition. This shows an inflow of a production technical culture present in the new bronze wares. The main component content of Cu is lower, and the Co and Fe contents (as microelements) are much higher than that of other bronze ware items. Such facts showthat those bronze ware items used completely different materials from bronze ware items in other cultural areas, or that there were differences in smelting techniques In the places where ancient bronze ware items have been extracted, it is presumed that the materials originated from the southern parts of Korea andnorthern parts and southern parts of China. .As more bronze ware scientific research is compiled one can conclude that that there will be enough scientific evidence to study the Bronze Age culture of Koreasystematically.

• Journal of Environmental Science International
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• v.11 no.3
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• pp.215-225
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• 2002

In order to evaluate the relationship between geochemical characteristics and benthic facies of the sediments from the Oenaro Island where red tide proliferation is first observed every year including this year, surface and short multiple core sediment samples were analyzed in terms of geochemical and benthic facies variation. The contents of organic carbon, carbonate, and sulfide gas were relatively low. The variation in C/N ratios, which indicate nature of organic carbon, suggested that the organic carbon recorded in the study area is composed of mixtures of marine and terrigenous organic matters. The concentration of minor elements found at the surface and multiple core sediment samples were also low as well as the enrichment factors(Ef) for the seven heavy metals indicated that the sediment of this area is not polluted significantly. The macrobenthic faunal community comprised 61 species, and their mean density was 708 ind./m2. Polychaete worms were major taxa of this benthic community. A crustacean amphipod, Melita sp. was the most abundant species accounted for 20.7% of total abundance, and the small polychaetes such as Heteromastus filiformis, Paralacydonia poradoxa, Magelona japonica and Sigambra tentaculata were the next dominant species. The macrobenthos around the Oenaro Island were more diverse and abundant than that in Gamak Bay. The benthic communities in the study area sustained somewhat different species composition based on the cluster analysis and the MDS ordination. The benthic community health condition at three stations seemed to be unbalanced, and slightly polluted based on the biological index such as BPI and BC. There was no clear relationship between the geochemistry characteristic and the benthic faunal facies attributed by the micro-algal blooms in this coastal area.

• Resources Recycling
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• v.9 no.3
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• pp.46-53
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• 2000

Recently, the efficient disposal of the waste rubber is necessary due to increasing amount of the waste rubbers. In this paper, method of recycling waste rubbers as components of medium for hydroponic rose culture was suggested. We investigated growth of rose, and macro- and micro-elements, pH and EC of the media amended with waste rubber, In the beginning of culture, stress symptoms such as thin brittle stem and incipient wilting were observed, but they disappeared in a few weeks. Concentration of $Zn^{2+}$ in media at flowering increased in proportion to contents of waste tire in the media. pH of media at flowering were in the range of 5.70 to 6.35. Rose growth in all media, except in wasterock wool mixed with EPDM powder at 9:3 ratio, was normal and equivalent to the control in terms of stem length, number of stems harvested and fresh weight.

• Communications of Mathematical Education
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• v.23 no.3
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• pp.849-862
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• 2009

The goal of this study is to present essential methods of minimalizing Korean populism in our society through the investigation of relations between populism and mathematical education which people don't easily recognize. We made a thorough analysis on the populism-generating elements and then presented mathematical methods which could convert micro-way of thinking into macro-one. We believe that an explicit investigation of the relations between Korean populism and mathematical education and the ensuing appropriate role-setting of mathematical education would help secure an essential solution for minimalizing populism in our society.

• Proceedings of the Ginseng society Conference
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• 2002.10a
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• pp.238-252
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• 2002

In order to screen out indicators for the discrimination of ginseng habitat, some physical and chemical characteristics of Korean red ginsengs (94 kinds) and Chinese red ginsengs (50 kinds) were analyzed by using a rheometer, an electronic nose system, a combined technique of solid phase micro-extraction (SPME) and gas chromatograph equipped with an electron capture detector (GC/ECD), an X-ray fluorescence spectrometer (XRF), an inductively coupled plasma mass spectrometer (ICP/MS), a near infrared spectrometer (NIRs) and high performance liquid chromatography equipped with evaporative light scattering detector (HPLC/ELSD). The results are summarized as follows: (i) The rhizome strengths of Korean red ginsengs were significantly higher than those of Chinese red ginsengs. (ii) The electronic nose patterns of Korean red ginsengs were significantly different from those of Chinese red ginsengs. (iii) Some unidentified peaks were detected not in the headspace of Korean red ginsengs but in the headspace of Chinese red ginsengs when the headspace volatiles prepared by the SPME technique were analyzed by GC/ECD. (iv) Either the content ratios of K to Ca or Mn to Fe were significantly different between Korean red ginsengs and Chinese red ginsengs. (v) The reflectance ratios of NIRs wavenumbers such as $904\;cm^{-1}\;to\;1088\;cm^{-1}$ for Korean red ginsengs were significantly different from those for Chinese red ginsengs. (vi) The content ratios of ginsenoside-Rg to ginsenoside-Re of Korean red ginsengs were significantly higher than those of Chinese red ginsengs. These results indicate that the rhizome strength, the electronic nose pattern, the occurrence of ECD-sensitive headspace volatile components, the content ratios of K to Ca and Mn to Fe, the NIRs pattern and the content ratio of ginsenoside-Rg to -Re may be indicators for the discrimination of ginseng habitat.

• Computers and Concrete
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• v.23 no.1
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• pp.61-68
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• 2019

This paper presents a computational rational model to predict the ultimate and optimized load capacity of reinforced concrete (RC) beams strengthened by a combination of longitudinal and transverse fiber reinforced polymer (FRP) composite plates/sheets (flexure and shear strengthening system). Several experimental and analytical studies on the confinement effect and failure mechanisms of fiber reinforced polymer (FRP) wrapped columns have been conducted over recent years. Although typical axial members are large-scale square/rectangular reinforced concrete (RC) columns in practice, the majority of such studies have concentrated on the behavior of small-scale circular concrete specimens. A high performance concrete, known as polymer concrete, made up of natural aggregates and an orthophthalic polyester binder, reinforced with non-metallic bars (glass reinforced polymer) has been studied. The material is described at micro and macro level, presenting the key physical and mechanical properties using different experimental techniques. Furthermore, a full description of non-metallic bars is presented to evaluate its structural expectancies, embedded in the polymer concrete matrix. In this paper, the mechanism of mechanical interaction of smooth and lugged FRP rods with concrete is presented. A general modeling and application of various elements are demonstrated. The contact parameters are defined and the procedures of calculation and evaluation of contact parameters are introduced. The method of calibration of the calculated parameters is presented. Finally, the numerical results are obtained for different bond parameters which show a good agreement with experimental results reported in literature.

• Journal of The Korean Association of Information Education
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• v.25 no.5
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• pp.713-721
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• 2021

As the Ministry of Education has introduced AI education in earnest in the 2022 revised curriculum, there is growing sympathy for the need for data-related education along with AI education. In order to develop the competence to understand and utilize artificial intelligence properly, the understanding and utilization competence of data must be based on it. In this study, a data-driven problem solving SW education program using microbit was developed by synthesizing the results of demand analysis and previous research analysis. The data-driven problem solving education program was developed with educational elements that can be applied to elementary school students among the contents of data science. Through the program developed in this study, education that combines various topics and subjects can be linked based on real-life data. Furthermore, based on an understanding of data, it will lay the foundation for a more substantial AI education program.

• Journal of Korean Society of Rural Planning
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• v.27 no.2
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• pp.1-11
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• 2021

In this study, in order to induce landscape-friendly various development plans established at the district level, the contents of landscape plans appearing in domestic laws and systems and related previous studies are reviewed and comparative analysis is performed to advance the district-level landscape plan. The main focus was to explore the institutional methodology for this. The summary of the research results is as follows. First of all, as a result of analysis of the landscape plan content prescribed in the National Territory Planning Act and the enforcement decree of the same Act, the landscape plan content for natural elements and the landscape plan content for artifacts appeared mixed. Next, looking at the analysis results of the landscape plan contents in the Landscape Act, the Enforcement Decree of the same Act, and the landscape plan establishment guidelines, it is analyzed that the content mainly intended to improve the artificial landscape in terms of aesthetics, such as color, lighting, and buildings. Became. As a result of analysis of the landscape plan contents in the district unit plan establishment guidelines, it was found that the contents of the landscape plan for the skyline, night view, color, advertisements, and viewpoints were presented. As a result of the analysis of the landscape plan contents in the preceding study, the plan contents for ecological, recreational, and micro-visual aspects were revealed, and all three aspects aim to establish a landscape plan within the range of minimizing damage to nature. there was. Appeared to be. The results of this study are considered to be able to induce more landscape and nature-friendly district unit plans being conducted at the district level.