• The Korean Journal of Community Living Science
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• v.19 no.4
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• pp.673-684
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• 2008

The purpose of this study is to compare the complexity of language level between verbally-precocious and typically-developing children from 2 to 3 years-old. Participants were 15 children classified as verbally-precocious were scored at the mean 56.85(expressive language) and 88.82(receptive language), and another 15 children classified as typically developing did at the mean 33.51(expressive language) and 58.01(receptive language) on MCDI-K. Each child's spontaneous utterances in interaction with her caregiver were collected at three different times with 6 months interval. All of the utterances were transcribed and analyzed for the use of MLU and lexical diversity by using KCLA. Summarizing the overall results, verbally-precocious children had significantly higher language abilities than typically-developing children at each time, and there were significant differences between two groups in syntactic and semantic language development, showing that verbally-precocious children indicated distinctive MLU and lexical diversity. These results suggest a high degree of stability in precocious verbal status, with variations in language complexity during conversations contributing to later differences in their language ability.

• Korean Journal of Child Studies
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• v.31 no.4
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• pp.15-27
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• 2010

This study was conducted in order to identify the relationship between home literacy environment and mother's interactive teaching behaviors, and infant's vocabulary ability. The subjects of this study were 53 infants between the ages of 18 to 24 months and their mothers. In order to measure the home literacy environment, the questionnaire used by Han Chan-Hee (2006), which was partly modified from Shapiro (1979), was selected, and to analyze mothers' teaching behaviors, Barnard's NCAST Teaching Scale(1978) was used. The infant's vocabulary ability was measured by the questionnaire first used by Lim Yong-Soon(2002), which was partly modified from the MCDI used by Fenson et al(1991). In conclusion, this study, most importantly, suggests that the teaching behaviors of the mothers themselves as well as the home literacy environment can both be very important factors affecting infant vocabulary development.

• Journal of the Korean Home Economics Association
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• v.50 no.2
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• pp.75-84
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• 2012

The purpose of this study was to examine the relationship between infants' turn-taking and vocabulary development during a one-year longitudinal study. Participants of this study included 46 infants who participated in both of the 1st and the 2nd tests. The infants' turn-taking frequencies were observed during mother-infant's free play for 10 minutes. The infants' vocabulary was investigated with MCDI-K for the 1st test and PRES for the 2nd test. The collected data were analyzed using both t-test and Pearson's correlation. The research results were as follows: First, the turn-taking frequencies and vocabulary of infants increased with age groups. Second, there was positive relationship between the turn-taking and the receptive vocabulary in group A at T1. Third, there were significant differences in receptive vocabulary at T1 and expressive vocabulary at T2 among group A according to the infants' turn-taking levels.

• Membrane Journal
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• v.25 no.1
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• pp.60-66
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• 2015

To investigate the performance of the composite carbon electrodes which the ion exchange polymers were directly casted onto porous carbon electrode surfaces, the adsorption/desorption experiments were carried out by varying the feed concentration, feed flow rate, and desorption voltages for the NaCl solution. When the feed concentration was 100 mg/L, the increase of the adsorption time led to the increase of the salt removal due to the increase of the residence time inside the cell while the increase of the feed flow rate from 15 mL/min to 23 mL/min gave the decrease of the salt removal efficiency, 12% because of the short residence time. When the feed concentration was 200 mg/L, the salt removal was shown 10~15% low because of the incomplete desorption within the desorption intervals.

• Membrane Journal
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• v.28 no.5
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• pp.332-339
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• 2018

In order to investigate the effect of ion exchange capacity of ion exchange membranes on the salt removal efficiency in the membrane capacitive deionization process, sulfosuccinic acid (SSA) as the cross linking agent was added to poly(vinyl alcohol)(PVA) and sulfonic acid-co-maleic acid (PSSA_MA) was put into PVA at different concentrations of 10, 50 and 90 wt% relative to PVA. As the content of PSSA_MA increased, the water content and ion exchange capacity increased and the salt removal efficiency was also increased in the membrane capacitive deionization process. The highest salt removal efficiency was 65.5% at 100 mg/L NaCl feed at a flow rate, 15 mL/min and adsorption, 1.4 V/5 min for PSSA_MA 90 wt%.

• Korean Journal of Child Studies
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• v.34 no.3
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• pp.1-19
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• 2013

The purpose of this study was to investigate the relationship between parents' behavior during picture-book reading and home literacy environment and their effects on toddlers' vocabulary. The subjects of the study were 46 toddlers and their parents. The MCDI-K(Im, 2002), Lee and Kim(2004)'s categories of Verbal Behaviors, the categories of Nonverbal Behavioral Analysis(Kim, 2005), and the Home Literacy Environment Index(Han, 2006) were used. The analysis of the collected data was guided by the research questions and involved the use of descriptive statistics, t-test and an analysis of relevant correlations. The results of this study were as follows; First, the toddlers' receptive vocabulary score was 1.2 times higher than the toddler's expressive vocabulary score. Second, the father's book reading behaviors and mother's book reading behaviors were quite similar, the most frequent types of behavior being the use of 'feedback', 'explanation', 'questioning' and 'pointing'. On the other hand, there was a significant difference between the reading behavior of the mother and father as regards the categories of 'linguistic attention ventilation', 'suggesting', 'directing(instructing)', 'expanding feedback', 'pointing' and 'gesture'. Mothers performed more of these behaviors than the fathers. Third, toddler's vocabulary scores were positively correlated with the mother's 'linguistic attention ventilation'. However, the mother's use of 'restriction' was negatively correlated with the toddler's vocabulary level. Toddler's vocabulary scores were positively correlated with the father's 'description', 'reasoning/predicting', 'questioning about function or action', 'demanding feedback' and 'pointing'. The toddler's vocabulary scores were also positively correlated with the relative abundance of home environment materials and the amount of time spent on parent-child home literacy activity.

• Membrane Journal
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• v.27 no.3
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• pp.240-247
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• 2017

In this study, the heterogeneous ion exchange membranes prepared by the combination of the carbon electrode and mixed the cation and anion exchange polymers and polyvinylidene fluoride as the basic polymer together were made to recognize the efficiency of the salt removal for the application of the membrane capacitive deionization process. The mixing weight ratio of the solvent, basic polymer and ion exchange resin was 7 : 2 : 1 and this mixed solution was directly cast on the electrode. As for the operating conditions of the adsorption voltage and time, feed flow rate, desorption voltage and time of the feed solution NaCl 100 mg/L, the salt removal efficiencies (SRE) were measured. Apart from this NaCl, the $CaCl_2$ and $MgSO_4$ solutions were investigated in terms of SRE as well. Typically, SRE for NaCl 100 mg/L solution under the conditions of adsorption voltage/time, 1.5 V/3 min, desorption voltage/time -0.1 V/3 min, was shown 98%. And for the $CaCl_2$ and $MgSO_4$ solutions, the SREs of 70 and 59% were measured under the conditions of adsorption voltage/time, 1.2 V/3 min, desorption voltage/time -0.5 V/5 min, respectively.