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Effect of Particle Sizes of Polymer Binders for Pigment Inks on Touch of Fabrics (안료 잉크용 바인더의 입자 크기가 직물의 태에 미치는 영향)

  • Park, Seongmin;Han, Minwoo;Jeong, Euigyung
    • Textile Coloration and Finishing
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    • v.32 no.4
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    • pp.226-231
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    • 2020
  • This study investigated effect of particle sizes of polymer binders for digital textile printing(DTP) pigment inks on touch of fabrics. The polymer binders were synthesized via miniemulsion polymerization of methyl methacrylate(MMA), butyl acrylate(BA), N-ethylolacrylamide(NEA) and methacrylic acid(MAA). The prepared binders were applied to black pigment inks and those black pigment inks were used to dye cotton fabrics. Then, color strength, rubbing fastness, stiffness, surface and bending properties of the dyed fabrics were investigated. Depending on the particle size of the polymer binder used, color strength, friction fastness, stiffness, surface and bending properties change. Generally, the larger the particle size of the polymer binder, the softer properties.

Insights into fuel behaviour during relatively fast thermal transients based on calculations for two tests of the Halden IFA-507 experiment

  • Grigori Khvostov
    • Nuclear Engineering and Technology
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    • v.55 no.10
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    • pp.3801-3807
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    • 2023
  • Outcomes of the project "Comprehensive Verification of the FALCON Code for Calculation of Nuclear Fuel Temperature" relating to calculation of fuel temperature during relatively fast thermal transients are presented. Good prediction capabilities of the FALCON MOD01 code coupled with the GRSW-A code are shown as applied to the data of the TF3 and TF5 tests from the Transient Temperature Experiment IFA-507. The IFA-507 related dataset of the OECD/NEA International Fuel Performance Experiments (IFPE) Database is extended by the reconstructed dynamics of the axial power distribution in the rods during the transient phase of the experiment. Based on the code calculation, the time constant of the thermal fuel response to a power transient is estimated.

Whole-core analysis of Watts bar benchmark with three-dimensional MOC code STREAM3D

  • Murat Serdar Aygul;Wonkyeong Kim;Deokjung Lee
    • Nuclear Engineering and Technology
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    • v.56 no.8
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    • pp.3255-3267
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    • 2024
  • This paper presents a high-fidelity simulation of the Organization for Economic Co-operation and Development (OECD) Nuclear Energy Agency (NEA) 3D whole-core Watts Bar benchmark using the UNIST in-house STREAM3D (Steady State and Transient Reactor Analysis code with Method of Characteristics) neutronic code. The benchmark encompasses various whole-core exercises, including single physics problems, multiphysics simulations, and depletion problems. When comparing parameters during the zero-power physics tests, including ITC, DBW, CRW, and criticality tests, STREAM3D results indicate a strong agreement with the measured data and KENO-VI. The comparison with the MC21/CTF code in 3D HFP BOC condition demonstrated strong agreement, with only a 0.42% difference in the normalized radial power distribution, a 0.38 K difference in the RMS of the assembly coolant exit temperature, and a mere 4 ppm difference in CBC.

Study on the Structure and Contents Analysis of America New School Library Standards Sets Standards for the 21st-Century Learner (미국 학교도서관 기준 관련 문서 "21세기 학습자를 위한 기준"의 구조와 내용 분석에 관한 연구)

  • Lee, Byeong-Ki
    • Journal of Korean Library and Information Science Society
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    • v.40 no.3
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    • pp.203-223
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    • 2009
  • The standards for school library in America affected school library policy in US as well as worlds. The America standards for school library established by NEA for the first time in 1920. After the first standard established, America standards revised about 10 times to accommodate educational and technological changes. The Americas new school library standards 'empowering learners: guidelines for school library media programs' established by AASL in 2009. The guidelines are relevant to the 'standards for the 21st-century learner', 'standards for the 21st-century learner in action'. The guidelines expected to affect US as well as school library policy of worlds. Thus, this study aimed to analyze the 'standards for the 21st-century learner' and 'standards for the 21st-century learner in action'. The standard for 21st-century learner offer vision for teaching and learning to both guide and beckon our profession as education leaders. They will both shape the library program and serve as a tool for library media specialists to use to shape the learning of students in the school. The standards for the 21st-century learner in action offer how are AASL's new learning standards, the standards for the 21st-century learner, incorporated into the school library.

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Analysis of Future Bioclimatic Zones Using Multi-climate Models (다중기후모형을 활용한 동북아시아의 미래 생물기후권역 변화분석)

  • Choi, Yuyoung;Lim, Chul-Hee;Ryu, Jieun;Jeon, Seongwoo
    • Journal of Environmental Impact Assessment
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    • v.27 no.5
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    • pp.489-508
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    • 2018
  • As climate changes, it is necessary to predict changes in the habitat environment in order to establish more aggressive adaptation strategies. The bioclimatic classification which clusters of areas with similar habitats can provide a useful ecosystem management framework. Therefore, in this study, biological habitat environment of Northeast Asia was identified through the establishment of the bioclimatic zones, and the impac of climate change on the biological habitat was analyzed. An ISODATA clustering was used to classify Northeast Asia (NEA)into 15 bioclimatic zones, and climate change impacts were predicted by projecting the future spatial distribution of bioclimatic zones based upon an ensemble of 17 GCMs across RCP4.5 and 8.5 scenarios for 2050s, and 2070s. Results demonstrated that significant changes in bioclimatic conditions can be expected throughout the NEA by 2050s and 2070s. The overall zones moved upward, and some zones were predicted to be greatly expanded or shrunk where we suggested as regions requiring intensive management. This analysis provides the basis for understanding potential impacts of climate change on biodiversity and ecosystem. Also, this could be used more effectively to support decision making on climate change adaptation.

Photoemission Electron Micro-spectroscopic Study of the Conductive Layer of a CVD Diamond (001)$2{\times}1$ Surface

  • Kono, S.;Saitou, T.;Kawata, H.;Goto, T.
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.7-8
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    • 2010
  • The surface conductive layer (SCL) of chemical vapor deposition (CVD) diamonds has attracting much interest. However, neither photoemission electron microscopic (PEEM) nor micro-spectroscopic (PEEMS) information is available so far. Since SCL retains in an ultra-high vacuum (UHV) condition, PEEM or PEEMS study will give an insight of SCL, which is the subject of the present study. The sample was made on a Ib-type HTHP diamond (001) substrate by non-doping CVD growthin a DC-plasma deposition chamber. The SCL properties of the sample in air were; a few tens K/Sq. in sheet resistance, ${\sim}180\;cm^2/vs$ in Hall mobility, ${\sim}2{\times}10^{12}/cm^2$ in carrier concentration. The root-square-mean surface roughness (Rq) of the sample was ~0.2nm as checked by AFM. A $2{\times}1$ LEED pattern and a sheet resistance of several hundreds K/Sq. in UHV were checked in a UHV chamber with an in-situ resist-meter [1]. The sample was then installed in a commercial PEEM/S apparatus (Omicron FOCUS IS-PEEM) which was composed of electro-static-lens optics together with an electron energy-analyzer. The presence of SCL was regularly monitored by measuring resistance between two electrodes (colloidal graphite) pasted on the two ends of sample surface. Figure 1 shows two PEEM images of a same area of the sample; a) is excited with a Hg-lamp and b) with a Xe-lamp. The maximum photon energy of the Hg-lamp is ~4.9 eV which is smaller that the band gap energy ($E_G=5.5\;eV$) of diamond and the maximum photon energy of the Xe-lamp is ~6.2 eV which is larger than $E_G$. The image that appear with the Hg-lamp can be due to photo-excitation to unoccupied states of the hydrogen-terminated negative electron affinity (NEA) diamond surface [2]. Secondary electron energy distribution of the white background of Figs.1a) and b) indeed shows that the whole surface is NEA except a large black dot on the upper center. However, Figs.1a) and 1b) show several features that are qualitatively different from each other. Some of the differences are the followings: the two main dark lines A and B in Fig.1b) are not at all obvious and the white lines B and C in Fig.1b) appear to be dark lines in Fig.1a). A PEEMS analysis of secondary electron energy distribution showed that all of the features A-D have negative electron affinity with marginal differences among them. These differences can be attributed to differences in the details of energy band bending underneath the surface present in SCL [3].

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Geological Factor Analysis for Evaluating the Long-term Safety Performance of Natural Barriers in Deep Geological Repository System of High-level Radioactive Waste (지질학적 심지층 처분지 내 천연방벽의 고준위 방사성 폐기물 장기 처분 안전성 평가를 위한 지질학적 인자 분석)

  • Hyeongmok Lee;Jiho Jeong;Jaesung Park;Subi Lee;Suwan So;Jina Jeong
    • Economic and Environmental Geology
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    • v.56 no.5
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    • pp.533-545
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    • 2023
  • In this study, an investigation was conducted on the features, events, and processes (FEP) that could impact the long-term safety of the natural barriers constituting high-level radioactive waste geological repositories. The FEP list was developed utilizing the IFEP list 3.0 provided by the Nuclear Energy Agency (NEA) as foundational data, supplemented by geological investigations and research findings from leading countries in this field. A total of 49 FEPs related to the performance of the natural barrier were identified. For each FEP, detailed definitions, classifications, impacts on long-term safety, significance in domestic conditions, and feasibility of quantification were provided. Moreover, based on the compiled FEP list, three scenarios that could affect the long-term safety of the disposal facility were developed. Geological factors affecting the performance of the natural barrier in each scenario were selected and their relationships were visualized. The constructed FEP list and the visualization of interrelated factors in various scenarios are anticipated to provide essential information for selecting and organizing factors that must be considered in the development of mathematical models for quantitatively evaluating the long-term safety of deep geological repositories. In addition, these findings could be effectively utilized in establishing criteria related to the key performance of natural barriers for the confirmation of repository sites.

Ten Years since Chernobyl Accident: a Review of Radiological Cosequences (체르노빌 원전사고 10년의 회고)

  • Lee, Jai-Ki
    • Journal of Radiation Protection and Research
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    • v.21 no.3
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    • pp.183-200
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    • 1996
  • Many information channels have dealt with the radiological consequences of the Chernobyl accident in different voices ever since the time of the accident. Large differences in the data about the amount of released radioactivity, losses of life, environmental effects and economic damage confuse the information receiving group. The intention of this paper is to provide an insight to the consequences of the accident through review of the reports and articles on the given issue and the scientific background. The formal reports reviewed include those from IAEA, EC, OECD/NEA, the governments of the two most-affected countries; Belarus and Ukraine. Much consideration was paid to make the text as plain as possible.

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Discrimination Analysis of Gallstones by Near Infrared Spectrometry Using a Soft Independent Modeling of Class Analogy

  • Lee, Sang-Hak;Son, Bum-Mok;Park, Ju-Eun;Choi, Sang-Seob;Nam, Jae-Jak
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.4106-4106
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    • 2001
  • A method to discriminate human gallstones by nea. infrared(NIR) spectrometry using a soft independent modeling of class analogy (SIMCA) has been studied. The fifty NIR spectra of gallstones in the wavenumber range from 4500 to 10,000 cm$\^$-1/ were measured. The forty samples were classified to three classes, cholesterol stone, calcium bilirubinate stone and calcium carbonate stone according to the contents of major components in each gallstone. The training set which contained objects of the different known class was constructed using forty NIR spectra and the test set was made with ten different gallstone spectra. The number of important principal components(PCs) to describe the class was determined by cross validation in order to improve the decision criterion of the SIMCA for the training set. The score plots of the class training set whose objects belong to the other classes were inspected. The critical distance of each class was computed using both the Euclidean distance and the Mahalanobis distance at a proper level of significance(${\alpha}$). Two methods were compared with respect to classification and their robustness towards the number of PCs selected to describe different classes.

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Workers' Experiences in Shift Work (근로자들의 교대근무 경험)

  • Kim, Young-Hea;Kim, Young-Mi;Koo, Mi-Jee;Kim, So-Hee;Lee, Nea-Young;Chang, Koung-Oh
    • Research in Community and Public Health Nursing
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    • v.18 no.2
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    • pp.284-292
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    • 2007
  • Purpose: The purpose of this study is to explore and understanding the nature of the shift workers' experience in industries requiring 24 hours-a-day service provision and support. For the Purpose, the present researcher made a research Question, "What are workers' experience in the shift work?" Methods: In the study, 5 male shift workers, 3 female shift worker and a woman (key informant) whose husband is a shift worker participated. Then profound interviews with the participants were made after their agreement. Results: The researcher classified the significant statements under 6 theme clusters, 1) sense of difference; 2) worries about health; 3) draining of emotion; 4) anxiety; 5) sadness; and 6) being comfortable. Conclusions: Shift work which is inevitable in modern society may have severe influences on shift workers' physical, mental and psychological aspects by causing their work cycle rhythm to be unbalanced. Finally, the researcher hopes that the results of the study would help understand workers' life and increase social concern and support to the workers.

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