• 재활복지
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• v.20 no.4
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• pp.247-264
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• 2016

The Children's Home Inventory for Listening Difficulties (CHILD) questionnaire has been applied for assessing listening and communication difficulties in various home situations for children with hearing loss. The purpose of the study was to translate the CHILD questionnaire for parents into Korean and verify reliability and validity of Korean version of CHILD (CHILD-K). CHILD-K was completed by 55 parents of children (from ages 3~12 years) using cochlear implants (CI). Among the 55 children, 27 were in preschool and 28 in elementary. Internal consistency reliability of CHILD-K was verified by Chronbach's alpha. The mixed factorial ANOVA was conducted to compare the effects of the age group and situation factors (Quiet, Noise, Distance, Social, and Media factors) on the score of CHILD. The results indicated that CHILD-K showed excellent internal consistency reliability (${\alpha}=.96$). The CHILD scores among age groups were significantly different as the older age group resulted in higher scores in all situations except Distance. For both groups the mean scores for the Quiet situation were significantly higher than other situations, and the mean scores for the Social situation were significantly lower than other situations. Moreover, analysis showed that children with CI had difficulties in the Social situation combined with other situation factors. The results indicate that the Korean version of CHILD questionnaire is a reliable tool for the assessment of communication abilities in home situation in Korean-speaking children using CI.

• Clean Technology
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• v.27 no.4
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• pp.367-371
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• 2021

The oxy-combustion system is one of the carbon recovery and storage technologies (CCS: Carbon capture & storage) that performs coal combustion using pure oxygen and recirculated flue gas. This is a technology that facilitates storage of carbon dioxide by generating an exhaust gas consisting of only carbon dioxide without a process of separating carbon dioxide and nitrogen when coal is burned using pure oxygen and recirculated flue gas mixture instead of a conventional air combustion system that produces carbon dioxide and nitrogen mixed exhaust gas. In this study, the characteristics of generated NO and SO₂ as atmospheric pollutants during oxy-combustion were examined using O₂/CO₂ mixed simulation gas. The reaction temperature was varied from 900 ℃ to 1200 ℃ and oxygen partial pressure was varied from 30% to 50%. The results showed that NO and SO₂ concentrations in flue gas increased as the oxygen concentration and the reaction temperature in the furnace increased. The partial pressure of CO₂ in flue gas also increased as the oxygen concentration and the reaction temperature in the furnace increased. As a results of comparing NO production of 30% O₂/CO₂ oxy-combustion with air combustion, NO in flue gas increased with reaction temperature in both experiments and NO of oxy-combustion was 40 ~ 80 ppm lower than that of air combustion.

• Composites Research
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• v.12 no.4
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• pp.71-78
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• 1999

To determine the effect of chemical structure of linear amine curing agents on thermal and mechanical properties, standard epoxy resin DGEBA was cured with diaminodiphenyl methane (DDM), diaminodiphenyl sulphone (DDS) in a stoichiometrically equivalent ratio. From this work, the effect of aromatic amine curing agents. In contrast, the results show that the DGEBA/DDS cure system having the sulfone structure between the benzene rings had higher values in the conversion of epoxide, density, shrinkage (%), glass transition temperature, tensile modulus and strength, flexural modulus and strength than the DGEBA/DDM cure system having methylene structure between the benzene rings, whereas the DGEBA/DDM cure system presented higher values in the maximum exothermic temperature, thermal expansion coefficient, and thermal stability. These results are caused by the relative effects of sulfone group having strong electronegativity and methylene group having (+) repulsive property and stem from the effect of the conversion ratio of epoxide group. The result of fractography shows that the each grain size of the DDM/DGEBA system with feather-like structure is larger than that of the DDS/DGEBA system.

• Applied Microscopy
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• v.32 no.1
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• pp.67-80
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• 2002

This study was carried out to investigate the effects of deer antler extract on the regeneration of peripheral nerves. Sprague-Dawley male rats weighing about 300 gm were fed deer antler extract for 1, 2, and 3 weeks per oral (1.5 ml/100 gm B.W.), respectively, once a day and transected both sides of sciatic nerve of each leg. After keeping for 6 hours, sciatic nerves taken from proximal part of transected region were treated with conventional transmission electron microscopical method and then observed with electron microscope. The results obtained were summarized as follows; 1. Sciatic nerves of normal control group were not showing any sprouts and electron dense axolemmal projections were frequently observed. 2. Sciatic nerves of saline treated groups were showing axonal sprouts at the nodes of Ranvier. The length of them was usually short, and numerous vesicles, vacuoles and organelles including neurofilament were contained. The number of nodes of Ranvier containing sprouts from 100 longitudinal sectioned nerve fibers was 29 (29%) in 1 week treated group, 32 (32%) in 2 weeks treated group, and 30 (30%) in 3 weeks treated group, respectively. 3. Sciatic nerves of deer antler treated groups were showing axonal sprouts at the node of Ranvier as well. Although most of the sprouts were short, some sprouts of 2 weeks and 3 weeks treated groups were quite long. Sprouts usually contained numerous vesicles, vacuoles and cell organelles such as neurofilaments and mitochondria. The number of nodes of Ranvier containing sprouts from 100 longitudinal sectioned nerve fibers was 38 (38%) in 1 week treated group, 46 (46%) in 2 weeks treated group, and 48 (48%) in 3 weeks treated group respectively. The results described above explain pretreatment of deer antler extract improves the sprout formation of transected sciatic nerves, and then it suggests deer antler may be effective for the regeneration of peripheral nerves.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.1
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• pp.119-128
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• 2010

The purpose of this study was to find a basic theory about Korean traditional planting pattern by analyzing a characteristic of planting and planted species in Haein, Tongdo and Songkwang Temples. The results are as follows. The planted species in three-treasure temples were 129 taxa; 57 families, 96 genera, 110 species, 12 varieties and 7 forma. The species related in Buddhism were Viburnum sargentii for. sterile, Hydrangea macrophylla for. otaksa and Musa basjoo. They are related in plant form and Buddhist ceremony. The results of forms were 34.1% in trees, 33.3% in shrubs, 3.9% in vine and 28.7% in herbage. The results of leaf fall were 56 taxa in broad-leaved deciduous trees, 27 taxa in broad-leaved evergreen trees and 14 taxa in needle-leaved evergreen trees. The native species were 32 taxa in Haein Temple, 27 taxa in Tongdo Temple and 44 taxa in Songkwang Temple. And the exotic species were 20 taxa, 28 taxa and 44 taxain the Haein, Tongdo and Songkwang Temples, respectively. In the results of analyzing the characteristics of planting, in the case of Haein Temple, Abies holophylla was linearly planted in Yiljumun, and Magnolia denudata was single planted in plant stairs of Haetalmun. In the case of plant stairs of Jeokmukdang, Cephalotaxus koreana was planted at regular intervals. In the case of Tongdo Temple, Celtis sinensis, Zelkova serrata and so forth were planted in Yiljumun, and Phyllostachys nigra was planted in form of screen planting in Youngsanjeon. The form of Hwanghwagak was a planting of symmetry in the center of a building, and the one of Daekwangmyyeongjeon was a mixed planting. The regular planting pattern was not shown in Yiljumun of Songkwang Temple. In the case of Dosungdang, Corunus officinalis was linearly planted in the west. In the case of Gwaneumjeon, Juniperus chinensis var. globosa and Camellia japonica were planted in symmetry. The old aged trees were planted in front of specimens planted in front of Daewoongbojeon.

• Restorative Dentistry and Endodontics
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• v.32 no.3
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• pp.180-190
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• 2007

The purpose of this study was to evaluate the abrasion resistance of surface penetrating sealant which was applied on a composite resin restoration and to provide proper time to reapply sealant on composite resin surface. Two hundred rectangular specimens, sized $8\times3\times2mm$, were made of Micronew (Bisco, Inc., Schaumburg, IL, U.S.A) and divided into two groups; F group (n = 10) was finished with coarse and medium grit of Sof-Lex discs and BisCoverwas applied B group (n = 190) after finishing with discs. B group was again subdivided into nineteen subgroups From B-1 group to B-18 group were subjected to toothbrush abrasion test using a distilled water-dentifrice slurry and toothbrush heads B-IM group was not subjected to toothbrush abrasion test. Average surface roughness (Ra) of each group was calculated using a surface roughness tester (Surfcorder MSE-1700: Kosaka Laboratory Ltd., Tokyo, Japan) . A representative specimen of each group was examined by FE-SEM (S-4700: Hitachi High Technologies Co., Tokyo, Japan). The data were analysed using cluster analysis, paired t-test, and repeated measure ANOVA. The results of this study were as follows; 1. Ra off group was $0.898{\pm}0.145{\mu}m$ and B-IM group was $0.289{\pm}0.142{\mu}m$. Ra became higher from B-1 group $(0.299{\pm}0.48{\mu}m$ to B-18 group $(0.642{\pm}0.313{\mu}m$. 2. Final cluster center of Ra was $0.361{\mu}m$ in cluster 1 $(B-IM\simB-7)$, $0.511{\mu}m$ in cluster 2 $(B-8\simB-14)$ and $0.624{\mu}m$ in cluster 3 ($(B-15\simB-18)$. There were significant difference among Ra of three clusters. 3 Ra of B-IM group was decreased 210.72% than Ra of F group. Ra of B-8 group and B-15 group was increased 35.49% and 51.35% respectively than Ra of B-IM group. 4. On FE-SEM, B-IM group showed the smoothest resin surface. B-8 group and B-15 group showed vertically shallow scratches , and wide and irregular vertical scratches on composite resin surface respectively. Within a limitation of this study, finished resin surface will be again smooth and glazy if BisCover would be reapplied within 8 to 14 months after applying to resin surface.