• Textile Coloration and Finishing
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• v.7 no.1
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• pp.10-22
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• 1995

Cellulosic fabrics, i.e. rayon, polynosic, and linen were treated with liquid ammonia at -33.4$^{\circ}C$. The fine structures, bending properties, tensile strength, wrinkle recoveries, and dyeing properties of the treated fabrics were studied. Dyeing was carried out with two direct dyes, C. I. Direct Red 2 and Blue 1. The liquid ammonia treatment for three fabrics brought about the transition of crystal lattices and the decrease of crystallinity; transforming cellulose I structure of original linen to cellulose I and III structure, and cellulose II structure of original rayon and polynosic to cellulose II and III structure. Moisture regain of liquid ammonia- treated polynosic and linen was higher than that for untreated, and water absorbency of liquid ammonia-traeated fabrics was all lower than that of untreated. Also, bending properties of treated fabrics were not improved compared with those of untreated ones. The rayon treated with liquid ammonia was increased not only the apparent diffusion coefficient and the rate of dyeing but also equilibrium dye adsortion, whereas polynosic and linen were increased only equilibrium dye adsortion. It is suggested that the pore sizes of liquid ammonia-treated rayon, polynosic, and linen are much smaller than that of liquid ammonia-treated cotton.

• Phonetics and Speech Sciences
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• v.6 no.4
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• pp.161-169
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• 2014

This study investigated changes in the prelinguistic vocal production of typically developing infants aged 5-20 months based on Stark Assessment of Early Vocal Development-Revised (SAEVD-R). Fifty-eight typically developing infants participated in the study, and they were divided into four age groups, 5-8 months, 9-12 months, 13-16 months, and 17-20 months of age. Vocalization samples were collected from infants' play activities and were classified into 5 levels and 23 types using SAEVD-R. The results revealed that the four age groups showed significant differences in production proportion of vocalization levels. Level 1, 2, 4, and 5 vocalizations exhibited significantly different across the four age groups. Level 3 was predominantly produced across every age group. Therefore, the vocalization level was not significantly different across the four age groups. Especially, vowels in Level 3 vocalization predominantly produced across all ages during a long period. Also, significant increases in the proportion of Levels 4 and 5 occurred after 9 months, which suggested that the production of cannonical syllables is a key indicator of advancement in prelinguistic vocal development. The results have clinical implication in early identification and speech-language intervention for young children with speech delays or at risk.

• Phonetics and Speech Sciences
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• v.6 no.4
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• pp.151-159
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• 2014

The study investigated the effects of reading intervention to enhance reading fluency for children from low-income families. The participants were 20 children from low-income families who are in grades 1 to 3. To qualify for participation in this study, all children had to score below 30 % ile on the Receptive vocabulary Test of the Expressive and Receptive Vocabulary Test or the Word reading fluency of the Korean Language-Based Reading Assessment. Participants were randomly assigned to the intervention (n=10) or control (n=10) group. The intervention group participated in the individualized intervention program using the guided repeated reading and the corrective feedback strategies. The results showed that participants in the intervention group performed better on reading fluency than those in the control group after participating in the intervention program. Specifically, guided repeated reading with corrective feedback strategies produced significant improvement on generalization to unpracticed passages as well as practiced passages. The results of this study suggest that guided repeated reading with corrective feedback is effective for enhancing reading fluency for children in Korea. Further study is needed in order to develop language-specific reading intervention.

• Speech Sciences
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• v.9 no.4
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• pp.77-91
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• 2002

This study investigated the use of grammatical morphemes (substantive morphemes and connective endings) of Korean speaking children with and without language impairment (LI). Participants were two children (ages 5;11 and 6;2) with SLI (specific language impairment), two LD (language delay) children (ages 6;3 and 6;5) with 70-84 range on a performance-IQ test, and two children (ages 5;7 and 6;1) with ND (normal development). Spontaneous language samples were elicited by play activities and story generation. A total of 8,059 (M=I,343, ranged 966-1,659) intelligible and nonimitative utterances were analyzed by the KCLA 2.0 (Korean Computerized Language Analysis 2.0) program for substantive morphemes and connective endings. The findings of this study were as follows; (1) The Korean speaking children with LI including SLI demonstrated less uses of grammatical morphemes than ND children. (2) Few differences were found between LI and ND children in the use of the grammatical morpheme types. (3) LI children produced significantly higher percentage of grammatical morpheme errors in spontaneous speech than ND children. (4) Few differences were found between SLI and LD children in degrees of the use and the error of grammatical morphemes.

• Korean Journal of Materials Research
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• v.16 no.2
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• pp.80-84
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• 2006

The removal efficiency of Cu and Fe contaminants on the silicon wafer surface was examined to investigate the effect of cleaning solutions on the behavior of metallic impurities. Silicon wafers were intentionally contaminated with Cu and Fe solutions by spin coating and cleaned in different types of cleaning solutions based on $NH_4OH/H_2O_2/H_2O\;(SC1),\;H_2O_2/HCl/H_2O$ (SC2), and/or HCl/$H_2O$ (m-SC2) mixtures. The concentration of metallic contaminants on the silicon wafer surface before and after cleaning was analyzed by vapor phase decomposition/inductively coupled plasma-mass spectrometry (VPD/ICP-MS). Cu ions were effectively removed both in alkali (SC1) and in acid (SC2) based solutions. When $H_2O_2$ was not added to SC2 solution like m-SC2, the removal efficiency of Cu impurities was decreased drastically. The efficiency of Cu ions in SC1 was not changed by increasing cleaning temperature. Fe ions were soluble only in acid solution like SC2 or m-SC2 solution. The removal efficiencies of Fe ions in acid solutions were enhanced by increasing cleaning temperature. It is found that the behavior of metallic contaminants as Cu and Fe from silicon surfaces in cleaning solutions could be explained in terms of Pourbaix diagram.

• Textile Coloration and Finishing
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• v.6 no.3
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• pp.1-7
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• 1994

Cotton fiber and NaOH-mercerized cotton fiber had been treated by liquid ammonia and were dyed with two direct dyes, C.I. Direct Red 2 and Blue 1. The effect of the treatment on the rate of dyeing, dye adsorption isotherm, and affinity were studied. The rate of dyeing was increased in the order of NaOH-mercerized> NaOH/liquid ammonia-treated > liquid ammonia-treated>Untreated cotton irrespective of kind of dyes. The rate of dyeing for NaOH-treated fiber considerably increased, whereas liquid ammonia-treated or NaOH/liquid ammonia-treated did not because the structural transformation was not enough for the dyes to penetrate easily into the liquied ammonia-treated cottons. The time of half-dyeing was considerably reduced by mercerizing with NaOH, but lengthened by liquid ammonia treatment because of increased equilibrium dye exhaustion especially in dyeing with C.I. Dierect Red 2. In spite of a short time of the ammonia treatment for 4 seconds, the equilibrium exhaustions of both of direct dyes, C.I. Direct Red 2 and C.I. Direct Blue 1, were increased in proportion to internal volume of treated cotton under a condition of fixed affinity.

• Phonetics and Speech Sciences
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• v.7 no.2
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• pp.29-38
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• 2015

This study explores reading fluency among elementary school students considering language level and family income(low SES). Forty eight students from 1st to 3rd grades participated in two paragraph reading tasks. Half of the children were from low income family and half of the children had low lexical knowledge. Reading fluency as in the number of correctly read syllables per minute, the total error frequency and error types were used to compare group differences. There were significant differences in the number of correctly read syllables per minute between two income groups and two language groups. There was a significant difference between low income group and non-low income group in total number of errors only when children's lexical knowledge were low. There were no group differences in error types of repetition and omission. Substitution and insertion error seemed to reflect the total error pattern. These results imply the importance of early screening and early involvement for children with low lexical knowledge from low income family. Monitoring and early intervention will support these children's reading development.

• Journal of the Semiconductor & Display Technology
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• v.4 no.4 s.13
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• pp.13-17
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• 2005

The behavior of ozone in $NH_4OH$ was investigated to evaluate the solution as a cleaning chemical of the silicon wafer. The solubility of ozone in DI(Deionized) water increased as the oxygen flow-rate decreased and ozone generator power increased. Ozone in DI water showed solubility of 100 ppm or higher at room temperature. Ozone concentration was stabilized at the range of ${\pm}2ppm$ by controlling oxygen flow rate and ozone generator power. On the contrary, the solubility of ozone in $NH_4OH$ was very low and strongly depended on the concentration of $NH_4OH$ and pH. The redox potential of ozone was saturated within 10 minutes in DI water and decreased rapidly with the addition of $NH_4OH$. The behavior of ozone in $NH_4OH$ is well explained by redox potential calculation.

• 한국태양에너지학회:학술대회논문집
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• 2011.04a
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• pp.293-298
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• 2011

The most widely used method to form an electrode in industrial solar cells are screen printing. Screen printing is characterized by a relatively simple and well-known production sequence with high throughput rates. However the method is difficult to implement a fine line width of high-efficiency solar cells can not be made. The open circuit voltage(Voc) and the short circuit current density(Jsc) and fill factor(FF) need to be further improved to increase the efficiency of silicon solar cells. In this study, gravure offset printing method using the multicrystalline-silicon solar cells were fabricated. Gravure off-set printing method which can print the fine line width of finger electrode can have the ability reduce the shaded area and increase the Jsc. Moreover it can make a high aspect ratio thereby series resistance is reduced and FF is increased. Approximately $50{\mu}m$ line width with $35{\mu}m$ height was achieved. The efficiency of gravure off set was 0.7% higher compare to that of scree printing method.

• Speech Sciences
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• v.8 no.4
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• pp.99-107
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• 2001

The purpose of this study was to investigate the syllable and phoneme frequencies in the spontaneous speech of some Korean children. Sixty four normally developing children aged from 2 to 5 were involved (male: female=1 : 1, 16 children in each age group). Fifty connected utterances were analyzed using the KCLA (Korean Computerized Language Analysis) 2.0 and Exel. The findings were as follows: 1) /i/ was the most frequently used syllable and was followed by /yo/, /k/, /s'/, /nen/ and so on. 2) The most frequently used Korean phonemes were syllable-initial consonant /k/, syllable- medial vowel /a/ and syllable-final consonant /n/. 3) All seven syllable final consonants (/p,t,k,m,n,n,l/) were used more frequently in the word-medial position than in the word-final position. Three syllable initial consonants(/k, I, s'/) were used more frequently in the word-medial position than in the word-initial position. The syllable and phoneme frequencies in the Korean children's spontaneous speech will provide valuable information in interpreting the severity of phonological disorder and in developing tools for the Korean phonological assessment and intervention.