• Title/Summary/Keyword: Property of matter

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Brain Metabolic Network Redistribution in Patients with White Matter Hyperintensities on MRI Analyzed with an Individualized Index Derived from 18F-FDG-PET/MRI

  • Jie Ma;Xu-Yun Hua;Mou-Xiong Zheng;Jia-Jia Wu;Bei-Bei Huo;Xiang-Xin Xing;Xin Gao;Han Zhang;Jian-Guang Xu
    • Korean Journal of Radiology
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    • v.23 no.10
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    • pp.986-997
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    • 2022
  • Objective: Whether metabolic redistribution occurs in patients with white matter hyperintensities (WMHs) on magnetic resonance imaging (MRI) is unknown. This study aimed 1) to propose a measure of the brain metabolic network for an individual patient and preliminarily apply it to identify impaired metabolic networks in patients with WMHs, and 2) to explore the clinical and imaging features of metabolic redistribution in patients with WMHs. Materials and Methods: This study included 50 patients with WMHs and 70 healthy controls (HCs) who underwent 18F-fluorodeoxyglucose-positron emission tomography/MRI. Various global property parameters according to graph theory and an individual parameter of brain metabolic network called "individual contribution index" were obtained. Parameter values were compared between the WMH and HC groups. The performance of the parameters in discriminating between the two groups was assessed using the area under the receiver operating characteristic curve (AUC). The correlation between the individual contribution index and Fazekas score was assessed, and the interaction between age and individual contribution index was determined. A generalized linear model was fitted with the individual contribution index as the dependent variable and the mean standardized uptake value (SUVmean) of nodes in the whole-brain network or seven classic functional networks as independent variables to determine their association. Results: The means ± standard deviations of the individual contribution index were (0.697 ± 10.9) × 10-3 and (0.0967 ± 0.0545) × 10-3 in the WMH and HC groups, respectively (p < 0.001). The AUC of the individual contribution index was 0.864 (95% confidence interval, 0.785-0.943). A positive correlation was identified between the individual contribution index and the Fazekas scores in patients with WMHs (r = 0.57, p < 0.001). Age and individual contribution index demonstrated a significant interaction effect on the Fazekas score. A significant direct association was observed between the individual contribution index and the SUVmean of the limbic network (p < 0.001). Conclusion: The individual contribution index may demonstrate the redistribution of the brain metabolic network in patients with WMHs.

A Matter of Autonomy in Art Criticism on Modernism (모더니즘 미술비평에 있어서 '자율성' (Autonomy)의 문제)

  • Choi Kwang-Jin
    • Journal of Science of Art and Design
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    • v.3
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    • pp.87-144
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    • 2001
  • This study looks into historical genealogy of autonomy in art criticism on modernism and presents the view of the judgment and correction about that. A matter of autonomy in art appeared in the attempt to totally reconsider and upset the theory of 'Mimesis' or 'Representation' which was the basis of traditional aesthetic theory. In the traditional theory of representation, they assumed primary image exists first and then tried to obtain visual similarity to it through art works. However, in the theory of autonomy in modernism, they maintained the reduction to pure form' or medium', regarding what art works represents and how similar to primary image are not the true essence of art. In the early 20th century, C. Bell laid the foundation stone of the theory of Formalism', providing that a matter of autonomy is significant form', which is the combination of lines and colors Aesthetic autonomy theory came to a climax by C. Greenberg, who systemized art criticism on modernism in the middle 20th century. According to his theory, the pursuit of the essence of form resulted in the specificity of medium' and flatness. They thought that the autonomy of art would be achieved by eliminating outward social factors from art works. This theory ended by Minimalism preventing the instructive function of art work and only emphasizing its material property. Since the middle 20th century, the autonomy theory was confronted with the limit and intense attack because it resulted in this fixed canon and materialism, so they began laying emphasis on those extrinsic factors around art works such as human life, society, history, and so on. This study focuses on arguing and complementing the limit of autonomy such as the adhesive and fixed canon, and then defining the more dynamic area of it. For this, first, I introduced the view of T. J. Clark and T. Crow who criticized the aesthetic autonomy theory. They denied the transcendental structure of form, and found form only in the association with substantial life and society. And they insisted the dynamism of form by emphasizing form as a result of negation insisted by avant-garde. Second, I researched the view of A. C, Danto and M. Fried, who complemented the traditional autonomy theory. They made autonomy emerge from the fixation of form like flatness through connecting essentialism with historical view. In conclusion, I insist that autonomic position of art make it possible to connect or mediate between material form and human or social elements. Therefore, autonomy should not be reduced to the axis of form or that of society but make interaction between two heterogeneous axes.

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Analysis of External Representations in Matter Units of 7th Grade Science Textbooks Developed Under the 2015 Revised National Curriculum (2015 개정 교육과정에 따른 7학년 과학교과서 물질 영역에 제시된 외적 표상의 분석)

  • Yoon, Heojeong
    • Journal of The Korean Association For Science Education
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    • v.40 no.1
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    • pp.61-75
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    • 2020
  • In this study, external representation presented in two units, 'Property of Gas' and 'Changes of States of Matter,' in seventh grade of 2015 revised science curriculum, were analyzed to suggest educational implications. External representations presented in five science textbooks were analyzed according to the six criteria, which were 'type of representation,' 'interpretation of surface features,' 'relatedness to text,' 'existence and properties of a caption,' 'degree of correlation between representations comprising a multiple one,' and 'function of representation.' The characteristics of typical representations related to each achievement standard of two units were also analyzed. The results were as follows: The macro representations for 'type of representation', and explicit representations for 'interpretation of surface features' showed highest frequency. For 'relatedness to text' criteria, 'completely related and linked' and 'completely related and unlinked' representations showed the highest frequency. It means that most representations were properly related with the text. There were appropriate captions for most representations. The degree of correlation between representations comprising a multiple one was largely sufficiently linked with regards to the criteria 'degree of correlation between representations comprising a multiple one'. The complete representations for 'function of representation' showed the highest frequency in the aggregate, however incomplete representations showed more frequencies in the inquiry parts. The typical representations for each achievement standard differed in terms of the type, contained information, used symbols and so on. The educational implications with the use of representations presented in seventh grade textbook were discussed.

Characterizing Fluorescence Properties of Dissolved Organic Matter for Water Quality Management of Rivers and Lakes (하천 및 호소 수질관리를 위한 용존 자연유기물질 형광특성 분석)

  • Hur, Jin;Shin, Jae-Ki;Park, Sung-Won
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.9
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    • pp.940-948
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    • 2006
  • Fluorescence measurements of dissolved organic matter(DOM) have the superior advantages over other analysis tools for applying to water quality management. They are simple and fast and require minimal pretreatment of samples. Fluorescence index($F_{450}/F_{500}$), synchronous spectra, and fluorescence excitation-emission matrices(EEM) of various DOM samples were investigated to discriminate autochthonous/allochthonous composition, protein-like fluorescence, fulvic-like fluorescence, humic-like fluorescence, terestrial humic-like fluorescence by comparing among the real DOM samples of different origins with the help of literature. The samples used included standard purified DOM, lake, river and wastewater treatment effluent. The relative distribution of various DOM composition was derived from the ratios of each fluorescence region. The results were very consistent with those expected from the sample properties. Allochthonous and terrestrial humic-like fluorescence were more prominent in the samples with abundant soil-derived DOM components. In addition, the protein-like fluorescence property was more pronounced in the samples where strong algal or microbial activities were expected. It was also shown that the ratio of protein-like/terrestrial humic-like fluorescence obtained from synchronous spectrum and fluorescence EEM could be used as an indicator for the evaluation of wastewater treatment on the downstream water quality of rivers and for the prediction of the degree of algal/microbial activities in lakes. It is expected that the results of this study will provide the basic information to develop the future water quality management techniques using DOM fluorescence measurements.

Soil Chemical Properties of Reclaimed Tide Lands Under Government Management in Korea: Results of 4-years monitoring (한국의 국가관리 간척지 토양의 화학성 변동: 4년 모니터링 결과)

  • Ryu, Jin-Hee;Lee, Su-Hwan;Oh, Yang-Yeol;Lee, Jeong-Tae
    • Korean Journal of Environmental Agriculture
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    • v.38 no.4
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    • pp.273-280
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    • 2019
  • BACKGROUND: The reclaimed lands for agricultural use managed by the Korean government is consisted of 17,145 hectares of lands under construction and 13,384 hectares of completed lands. In order to utilize these reclaimed lands as competitive agricultural complexes, the government is preparing to develop comprehensive development plans for multiple purposes. For rational land-use planning and soil management, information of the soil chemical properties is necessary. METHODS AND RESULTS: From 2013 to 2016, soil samples were collected from 85 representative sampling sites of the reclaimed lands and analyzed for soil chemical properties including electric conductivity (EC), pH, soil organic matter (SOM), and nutrients. The annual mean soil EC ranged from 5.1 to 8.3 dS m-1 and have continued to decrease over the years (estimation equation with EC as dependent and year as independent variable was y =0.0736x2 - 1.4985x + 9.8305, R2 = 0.9753). The pH ranged from 7.3 to 7.6, which was higher than the optimum range (5.5~7.0) for agricultural soils. Soil organic matter (8 to 11 g kg-1) was lower level than the optimum range (20~30 kg-1). Available silicate (Av.SiO2) ranged from 169 to 229 mg kg-1, which was close to the minimum content (≥157 mg kg-1) for rice paddy field. Available phosphate (Av.P2O5) content (24~39 mg kg-1) was lower than the optimum range (80~120 mg kg-1) for rice paddy field. CONCLUSION: For efficient agricultural use of reclaimed lands under government management, our results suggest that the application of organic matter and supplying deficient nutrients as well as desalinization is required.

Effect of Winter Rye Cultivation to Improve Soil Fertility and Crop production in Alpine Upland in Korea (동계호밀재배가 고랭지 밭토양의 비옥도 증진에 미치는 영향)

  • Zhang, Yong-Seon;Lee, Gye-Jun;Joo, Jin-Ho;Lee, Jeong-Tae;Ahn, Jae-Hoon;Park, Chol-Soo
    • Korean Journal of Environmental Agriculture
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    • v.26 no.4
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    • pp.300-305
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    • 2007
  • Soil erosion is one of the most serious problems in alpine upland in Korea. Soil fertility has continuously decreased due to serious soil erosion. To increase soil fertility, new sources of organic matter should be inputted. Therefore, the objectives of this research were to select winter cover crop as new sources of organic matter and to investigate the effect of winter cover crop on soil property changes, major crop productivity (Chinese cabbage, potato) production in highland, and disease occurrence with different cropping systems. Among 17 candidates for winter coverage crop, rye was most suitable due to it's soil covering rate, and over-wintering rate. The optimum sowing period for rye ranged from late August to late September. Soil porosity and organic matter content increased with rye cultivation. Rye cultivation during winter increased amounts of crop (both Chinese cabbage and potato) productivity up to 8%. There was little difference on amount of crop productivity depending on cropping systems such as monoculture (Chinese cabbage or potato) and Chinese cabbage-potato rotation.

A Study on the Clothing Practices of Korean High School Students (남여 고등학생의 의생활실태에 관한 조사연구 -착용선택기준과 착용감을 중심으로-)

  • Park Woo Mi
    • Journal of the Korean Society of Clothing and Textiles
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    • v.8 no.1
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    • pp.75-84
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    • 1984
  • The main purpose of the study were to investigate a selection motive of clothing and the feeling of wearing of Korean high school students. The results were as follows ; 1. For underwear, the body appearance and the hygienical aspect were shown as important factors in a selection motive of clothing. And the property of matter and hygienical aspect were shown as important factors in the feeling of wearing. 2. For outwear, a functionality and the psychological aspect were shown as important factors in a selective motive of clothing. And a exeroise and the psychological aspect were shown as important factors in the feeling of wearing. 3. For skirt, the psychological aspect was shown as an important factor in a selection motive of clothing and the feeling of wearing. For pants, a functionality was shown as an important factor in a selection motive of clothing. 4. A exercise was shown as an important factor in the feeling of wearing with the silhouette of outwear. 5. The hygienical aspect was shown as an important factor in the demand of selection motive of clothing for comfort.

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Improvement of Gate Dielectric Characteristics in MOS Capacitor by Deuterium-ion Implantation Process (중수소 이온 주입에 의한 MOS 커패시터의 게이트 산화막 절연 특성 개선)

  • Seo, Young-Ho;Do, Seung-Woo;Lee, Yong-Hyun;Lee, Jae-Sung
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.24 no.8
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    • pp.609-615
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    • 2011
  • This paper is studied for the improvement of the characteristics of gate oxide with 3-nm-thick gate oxide by deuterium ion implantation methode. Deuterium ions were implanted to account for the topography of the overlaying layers and placing the D peak at the top of gate oxide. A short anneal at forming gas to nitrogen was performed to remove the damage of D-implantation. We simulated the deuterium ion implantation to find the optimum condition by SRIM (stopping and range of ions in matter) tool. We got the optimum condition by the results of simulation. We compare the electrical characteristics of the optimum condition with others terms. We also analyzed the electrical characteristics to change the annealing conditions after deuterium ion implantation. The results of the analysis, the breakdown time of the gate oxide was prolonged in the optimum condition. And a variety of annealing, we realized the dielectric property that annealing is good at longer time. However, the high temperature is bad because of thermal stress.

Design and Performance Analysis of Environment Friendly Double Core Bullets for Small Arms (친환경 소화기용 탄심 재료 및 2중 구조 설계 분석)

  • Hong, Jun-Hee;Jang, Tak-Soon;Song, Chang-Bin;Kim, Byung-In
    • Journal of the Korea Institute of Military Science and Technology
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    • v.14 no.2
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    • pp.264-270
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    • 2011
  • This paper focuses on possibility to design and fabrication new combination of bullet core to substitute current toxic material of heavy metal such as lead by environment-friendly ones. The core is designed as dual structure to manipulate the core center of gravity easily by combining materials, which of basis is tungsten of low cost and easily acquired. Those combinations are W-M series such as W-Cu, W-Sn, W-Cu-Sn, and W-Cu-Ni to target the density of lead, $11.34g/cm^3$ through powder-metallurgy. Out of four, combination of W-Cu-Ni shows the highest compression density of 96% and is confirmed as the most suitable substitution for lead due to the excellent property of matter and sintering. All combination samples is simulated on the PRODAS software for designing and structure analysis by adjusting the center of gravity of dual core samples forward and backward. The simulations confirm the similarity of current bullet core with respect to properties of mass, aero dynamics, and flying stability.

Thermal Property of CNT/Cu Nanocomposite (Carbon Nanotube/Cu 나노복합체의 열적특성)

  • Hong, Youn-Jeong;Kim, Hye-Jin;Jung, Chung-Hun;Lee, Kyu-Mann
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.11a
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    • pp.89-90
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    • 2006
  • The CNTs are of great interest because of their unique complete properties of matter, especially, the large thermal conductivity (Thermal conductivity of CNTs ~ >2000W /mK vs. Thermal conductivity of Aluminum ~ >204W/mK). However, owing to the strong agglomeration cause by the vander wall's force, the CNTs are limited to applicate. In this study. we suggest a new method for CNTs dispersion. which are developed by the mechanical and chemical method. and then Cu was coated. This new process produces CNTs/Cu nanocomposite powders. The CNTs are homogeneously located within the Cu powders by chemical reaction. And the thermal properties of the CNTs/Cu nanocomposite were investigated.

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