• Corrosion Science and Technology
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• v.2 no.4
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• pp.165-170
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• 2003

Atmospheric corrosion behaviors of Zn, Zn-5%Al and Zn-55%A l coated steels have been investigated under cyclic wet-dry environments containing chloride ions. The wet-dry cycle was carried out by alternate exposure to immersion in 0.5 M (or 0.05 M) NaCl solutions and drying at $25^{\circ}C$ and 60 %RH. The polarization resistance $R_p$ and solution resistance $R_s$ were monitored by AC impedance technique. From the obtained $1/R_p$ and $1/R_s$ values, the corrosion rate of the coatings and the Time of Wetness (TOW) were estimated, respectively. Effects of chloride ions and TOW on the corrosion rates of Zn, Zn-5%Al, Zn-55%Al coatings and appearance of red rust (onset of underlying steel corrosion) under wet-dry cycles are discussed on the basis of the corrosion monitoring data.

• Korean Journal of Adult Nursing
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• v.24 no.2
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• pp.160-170
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• 2012

Purpose: The aim of this study was to assess knowledge, attitude, correct metered dose inhaler (MDI) use and compliance with self management among patients with chronic obstructive pulmonary disease (COPD). Methods: The participants of this study consisted of 109 COPD patients who were outpatients in C and K hospital located in G city from March 1 to September 30th, 2010. Data were measured using self-administered questionnaires and observational checklist. The data were analyzed using SPSS/WIN 18.0 program that included mean, standard deviation, ANOVA, Sheffe test, and Pearson's correlation. Results: There were significant relationships between knowledge and attitude (r=.33, $p$ <.001), between knowledge and correct MDI use (r=.37, $p$ <.001), and between knowledge and self-management compliance (r=.28, $p$=.003). There was significant relationship between attitude and self-management compliance (r=.33. $p$ <.001). In contrast, attitude was not significantly related to correct MDI use. Conclusion: The study showed that COPD knowledge and attitude of patients were related compliance in managing their disease. Therefore, strategies need to be utilized in education programs which would improve knowledge and subsequently improve attitude and compliance.

• Proceedings of the KSLP Conference
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• 2003.11a
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• pp.170-173
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• 2003

There are more than five systems for transcribing English vowels. Because of this diversity, teachers of English and students are confronted with not a little problems with the English vowel symbols used in the English-Korean dictionaries, English text books, books for Phonetics and Phonology. This study was designed to suggest criterions for the phonemic transcription of English vowels on the basis of phonetic properties of the vowels and a system of English vowel transcription based on the criterions in order to minimize the problems with inter-system differences. A speaker (phonetician) of RP English uttered a series of isolated minimal pairs containing the vowels in question. The suggested vowel symbols are as follows: 1) Simple vowels : /i:/ in beat, /I/ bit, /$\varepsilon$/ bet,/${\ae}$/ bat, /a:/ father, /Dlla/ bod, /$\jmath$:/ bawd, /u/ put, /u:/ boot /$\Lambda$/ but, and /$\partial$/ about /$\Im$:ll$\Im$:r/ bird. 2) Diphthongs : /aI/ in bite, /au/ bout, /$\jmath$I/ boy, /$\Im$ullou/ boat, /er/ bait, /e$\partial$lle$\partial$r/ air, /u$\partial$llu$\partial$r/ poor, /i$\partial$lli$\partial$r/ beer. Where two symbols are shown corresponding to the vowel in a single word, the first is appropriate for most speakers of British English and the second for most speakers of American English.

• KSBB Journal
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• v.18 no.3
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• pp.170-173
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• 2003

This study was studies biophoton characteristics of Madin-Darby canine kidney cells under the influence of CsA and each cell type (mock, wt, R55A) by employing a Photomultipliertube. $\textrm{H}_2\textrm{O}_2$ was used for producing reactive oxygen species (ROS) in this measurement. ROS is also generated during oxidative metabolism in living organism. Images from a fluorescence show an increase of photon intensity emitted from the sample on the influence of CsA and each cell type (mock, wt, R55A). It is believed chemiluminescence (CL) occurred by ROS is responsible for the biophoton emission. hence PMT measurement might be considered as a useful tool for studying biochemical characteristics in relation to ROS.

• Journal of Powder Materials
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• v.11 no.2
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• pp.165-170
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• 2004

Growth behavior of two different types of grains, faceted and rounded, in a liquid matrix has been studied in the (75WC-25TiCN)-30Co system. Powder samples were sintered above the eutectic temperature for various times under a carbon saturated condition. (Ti,W)(C,N) grains with a rounded shape and WC grains with a faceted shape coexisted in the same Co based liquid. With increasing sintering time, the average size of (Ti.W)(C,N) grains increased continuously and very large WC grains appeared. The growth of rounded (Ti,W)(C,N) grains followed a cubic law, r^3-r^3_0$=kt, where r is the average size of the grains, $r_0$ the initial average size, k the proportionality constant and t the sintering time. indicating a diffusion-controlled growth. On the other hand, the growth of the faceted WC grains resulted in a bimodal grain size distribution, showing an abnormal grain growth. These observations show that the growth behavior of different types of grains is governed by their shape, faceted or rounded, even in the same liquid matrix.

• Carbon letters
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• v.16 no.1
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• pp.62-66
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• 2015

In this study, carbonized fibers were prepared by using acidically cross-linked LDPE fibers. The surface morphologies of the carbonized fibers were observed by SEM. The effects of cross-linking process temperatures were studied using thermal analyses such as DSC and TGA. The melting and heating enthalpy of the fibers decreased as the cross-linking temperature increased. The cross-linked fibers had a carbonization yield of over 50%. From SEM results the highest yield of carbonized LDPE-based fibers was obtained by cross-linking at a sulfate temperature ($170^{\circ}C$). As a result, carbonation yield of the carbonized fibers was found to depend on the functions of the cross-linking ratio of the LDPE precursors.

• Spatial Information Research
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• v.8 no.1
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• pp.155-170
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• 2000

When we use R-Tree,a spatial index, to find objects matches some predicate, it often leads to an incorrect result of perform filtering step only with MBR. And , each candidates need to be inspected to conform if it really satisfies with given query, so called, 'refinement step'. In refinement step. we should perform disk I/O and expansive spatial operations which is the cause of increasing retrieval costs. Therefore, to minimize the number of candidate after filtering step, two-phase filtering methods were studied, but there was many problems such as inefficiency of filtering,maintenance of additional informations and reconstruction of data resulted from the loss of original information. So , in this paper, I propose an Extended R-Tree which provides ability to retrieve spatial objects only with some simple logical operations using Grid Table, truth table strong the information about the existence of spatial objects, in second filtering step. Consequently , this Extended R-Tree using Grid Filter has low cost of operation for filtering because of efficient second filtering step, and better filtering efficiency caused by high quality of approximation.

• Physical Therapy Rehabilitation Science
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• v.9 no.3
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• pp.165-170
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• 2020

Objective: To investigate the association between one-leg standing ability and postural control for chronic hemiparetic stroke. Design: Cross-sectional study. Methods: Forty individuals who had a first diagnosis of stroke with hemiparesis before six months and over had participated in this study. To analyze the relationship between one-leg standing ability and postural control in the participants, six clinical measurement tools were used for assessment, including the Timed-Up-and-Go (TUG) test, Berg Balance Scale (BBS), Dynamic Gait Index (DGI), Fugl-Meyer Assessment (FMA), 5 times sit-to-stand (5TSTS) and one-leg standing (OLS). Results: After analyzation, the OLS scores in the more-affected side showed significant positive correlations with BBS scores (r=0.469, p<0.01), DGI scores (r=0.459, p<0.01).and FMA scores (r=0.425, p<0.01). The OLS scores in the more-affected side showed significant negative correlations with TUG score (r=-0.351, p<0.05). The OLS score in the less-affected side showed significant positive correlations with BBS scores (r=0.485, p<0.01), DGI scores (r=0.488, p<0.01) and FMA score (r=0.352, p<0.05). The OLS scores in the less-affected side showed significant negative correlation with TUG scores (r=-0.392, p<0.05) and 5TSTS (r= -0.430, p<0.01). The OLS scores in the more-affected side showed significant positive correlations with the OLS scores in less-affected side (r=0.712, p<0.01). Conclusions: The results of the study suggest that the OLS time may be moderately correlated with static and dynamic postural stabilities and motor recovery following stroke. This study also suggests that the OLS test is as a simple clinical tool for predicting postural control performance for individuals with chronic hemiparetic stroke.

• Journal of the Korean Solar Energy Society
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• v.33 no.1
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• pp.15-23
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• 2013

In this study, thermodynamic performance of R435A is examined both numerically and experimentally in an effort to replace HFC134a used in the refrigeration system of domestic water purifiers. Even though HFC134a is used predominantly in such a system these days, it needs to be phased out in the near future in Europe and most of the developed countries due to its high global warming potential. To solve this problem, cycle simulation and experimental measurements are carried out with a new refrigerant mixture of 20%R152a/80%RE170 using actual domestic water purifiers. This mixture is numbered and listed as R435A by ASHRAE recently. Test results show that the system performance with R435A is greatly influenced by the amount of charge due to the small internal volume of the refrigeration system of the domestic water purifiers. With the optimum amount of charge of 21 to 22 grams, about 50% of HFC134a, the energy consumption of R435A is 11.8% lower than that of HFC134a. The compressor discharge temperature of R435A $8^{\circ}C$ lower than that of HFC134a at the optimum charge. Overall, R435A, a new long term environmentally safe refrigerant, is a good alternative for HFC134a requiring little change in the refrigeration system of the domestic water purifiers.

• Journal of Ocean Engineering and Technology
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• v.36 no.4
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• pp.217-231
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• 2022

Reinforced polyurethane foam (R-PUF), a material for liquefied natural gas cargo containment systems, is expected to have different mechanical properties depending on its stacking position of foaming as the glass fiber reinforcement of R-PUF sinks inside R-PUF under the influence of gravity. In addition, since R-PUF is not a homogeneous material, it is also expected that the coordinate direction within this material has a great correlation with the mechanical properties. So, this study was conducted to confirm this correlation with the one between the mechanical properties and the stacking position. In particular, in this study, R-PUF of 3 different densities (130, 170, and 210 kg/m³) was used, and tensile, compression, and shear tests of this material were performed under 5 temperatures. As a result of the tests, it was confirmed that the strength and modulus of elasticity of the material increased as the temperature decreased. Specifically, the strength and modulus of elasticity in the Z direction, which was the lamination direction, tended to be lower than those in the other directions. Finally, the strength and elastic modulus of different specimens of the material found at the bottom of their lamination compared to the specimens with these properties found at positions other than their lamination bottom were evaluated. Further analysis confirmed that as the temperature decreased, hardening of R-PUF occurred, indicating that the strength and modulus of elasticity increased. On the other hand, as the density of R-PUF increased, a sharp increase in strength and elastic modulus of R-PUF was observed.