• Journal of the Korean Crystal Growth and Crystal Technology
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• v.30 no.1
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• pp.33-39
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• 2020

Lightweight geopolymers were fabricated by using fused slag from integrated gasification combined cycle as a law material and Si sludge from silicon wafer process as a bloating material for the purpose of replacing autoclaved lightweight concrete (ALC). Density and compressive strength of geopolymers were measured and compared with the properties of ALC according to the variation of mol concentration of alkaline activator, W/S ratio, addition of fibers, and addition of polystyrene and the possibility of replacing ALC panel was estimated through the comparisons. Although the geopolymer satisfying the standard of ALC panel was not made by controlling mol concentration and W/S ratio, addition of inserts such as fibers and polystyrene insert was tried to overcome the obstacle of enhancing properties. Geopolymers cannot satisfying the standard of ALC panel by adding carbon or glass fibers; however, adding fibers can be suggested as one of the methods enhancing compressive strength because the compressive strength of the specimen containing 0.3 wt.% glass fibers was increased by 3 times. The maximum addition of polystyrene insert was turned out to be 50 vol.% and the properties of geopolymers varied by the method of insertion. When using single polystyrene insert, compressive strength was 17.8 MPa and density was 0.996 g/㎤ which were similar values to the standard of ALC panel. If the difficulties of reproductivity of production and insertion method of inserts were overcome through the future research, the geopolymers containing polystyrene inserts could possibly replace ALC panel.

• Journal of Korea Port Economic Association
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• v.29 no.2
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• pp.39-61
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• 2013

China, a leader of regional economies in North-East Asia, helps to integrate a single shipping market and affects diversely main ports in the region through affecting the flows of container transshipment, strategies of shipping companies for port calling and shipping networks. This study examines competition and cooperation among the hub ports in the region through studying examples of the three Chinese hub ports -Hong Kong, Shanghai, and Tianjin- and concludes some implications of status change of hub ports in the region after scrutinising development process of the Chinese main hub ports and the historic interaction of port development among these ports. The characteristics of growth pattern of three ports are as follows. The port of Hong Kong constructs step by step the container facilities in accordance with demand growth and prefers stabilisation of operation and management through scale enlargement of port facilities. Even though demand grows continually, the port of Shanghai continued its defensive attitude towards facility expansion till the 1990s and has tried to get economies of scale in enlargement of port facilities. The port of Tianjin, similarly as the two other ports, expands serially its facilities and utilizes the capacity concentration and functional specialisation of facilities. The analysis of panel data and panel regression of three hub ports implicates that each port has its own specific demand and shows that the interaction of container handling among three ports was weak in 1980s and has become stricter and stronger since 1990.

• Korean Journal of Food Science and Technology
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• v.12 no.3
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• pp.150-157
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• 1980

In an attempt to evaluate the quality of food by sensory testing, the difference testing for commercial milk was conducted by selected members of a sensory panel. The results were summarized as follows: 1. Sensory panel of 40 persons were selected by the general basis of selection of panel members, by sensitivity test for primary taste, and by discriminatory ability test and trained to have normal abilities on the sensory testing for the quality of milk. 2. As a result of sensitivity test for 4 primary tastes by panel members, the solution concentration of salt, sour, bitter and sweet for which average recognition threshold was located were 0.0128 M sodium chloride, 0.0008 M citric acid, 0.0016 M caffeine and 0.0256 M sucrose, respectively. 3. As results of difference test of single stimuli, paired comparison test, duo-trio test and triangle test, a significant difference was recognized at higher level than the 1% among the samples of commercial milk produced by 5 companies.

• Journal of Families and Better Life
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• v.35 no.1
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• pp.1-16
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• 2017

Using data from the 2015 Korea Welfare Panel Study, we examined the predictors of psychological well-being (life satisfaction and depression) of single elderly people living alone across development stages (young-old, mid-old, and old-old) and suggested implications for elderly policy. For this purpose, we selected 1,364 elderly people who lived alone but preserved their family relationships, and were 65 years of age or older. Separate analyses were conducted for the three groups of single elderly people living alone. Overall, the psychological well-being of single elderly people living alone was higher than moderate level, and they were generally satisfied with their everyday lives and less depressed. However, there were group differences: the young-old group was more satisfied than the old-old group with in their everyday lives and less depressed than the mid-old and old-old groups. In the young-old group, life satisfaction was significantly associated with subjective health, non-physical conflict with family, disposal income, house ownership, dietary deficiency, cost of living, and public pension. In addition, depression was significantly associated with subjective health, non-physical conflict with family, dietary deficiency, and physical conflict with family. In the mid-old group, life satisfaction was significantly associated with subjective health, housing non-physical conflict with family, disposal income, and dietary deficiency. Depression was significantly associated with subjective health, housing deficiency. In the old-old group, life satisfaction was significantly associated with subjective health and non-physical conflict with family. Depression was significantly associated with subjective health. Therefore, 'health'and 'family'are important key concepts to consider when making elderly policy.

• Journal of the Korea Convergence Society
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• v.12 no.8
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• pp.67-75
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• 2021

This study was conducted to verify the factors affecting self-esteem of the 50-69 aged with low income in single person households. The subjects were 233 single households in the 50-69 aged low income from the 2019 welfare panel data provided by the Ministry of Health and Welfare. The dependent variable was defined as self-esteem, and independent variables were relationship satisfaction and life satisfaction. Data analysis was carried out by using SEM analysis, As a result, relationship satisfaction did not have a direct effect on self-esteem, with a low value (path coefficient =0.24). However, relationship satisfaction positively influenced life satisfaction (path coefficient =0.71), and life satisfaction positively influenced the self-esteem (path coefficient =0.46). Thus life satisfaction between relationship satisfaction and self-esteem had a mediator effect on self-esteem with 0.32 value. Therefore, establishing the strategy which supports poor single person households, policy makers should consider methods improving relationship satisfaction and life satisfaction.

• Journal of Animal Science and Technology
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• v.58 no.4
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• pp.14.1-14.9
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• 2016

Background: Peroxisome proliferator-activated receptor gamma (PPARG), CCAAT/enhancer binding protein alpha (CEBPA) and retinoid X receptor alpha (RXRA) are nuclear transcription factors that play important roles in regulation of adipogenesis and fat deposition. The objectives of this study were to characterise the variability of these three candidate genes in a mixed sample panel composed of several cattle breeds with different meat quality, validate single nucleotide polymorphisms (SNPs) in a local crossbred population (Angus - Hereford - Limousin) and evaluate their effects on meat quality traits (backfat thickness, intramuscular fat content and fatty acid composition), supporting the association tests with bioinformatic predictive studies. Results: Globally, nine SNPs were detected in the PPARG and CEBPA genes within our mixed panel, including a novel SNP in the latter. Three of these nine, along with seven other SNPs selected from the Single Nucleotide Polymorphism database (SNPdb), including SNPs in the RXRA gene, were validated in the crossbred population (N = 260). After validation, five of these SNPs were evaluated for genotype effects on fatty acid content and composition. Significant effects were observed on backfat thickness and different fatty acid contents (P < 0.05). Some of these SNPs caused slight differences in mRNA structure stability and/or putative binding sites for proteins. Conclusions: PPARG and CEBPA showed low to moderate variability in our sample panel. Variations in these genes, along with RXRA, may explain part of the genetic variation in fat content and composition. Our results may contribute to knowledge about genetic variation in meat quality traits in cattle and should be evaluated in larger independent populations.

• Journal of the Korean Wood Science and Technology
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• v.28 no.3
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• pp.1-8
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• 2000

To develop the technology of producing structural board from low grade materials, an attempt was made to produce strand/particle composites from split wood strand(S) and particle(P) of (Cryptomeria japonica D. Don), which changed the layer construction and the ratio of S/P. The influence of layer construction on board properties was determined, focusing on the number and alignment of the S layers. The effect of weight ratio of S/P (3:7, 1:1, 7:3) on mechanical properties was also discussed on seven layered panel. Mechanical properties were determined from static bending tests to give parallel and perpendicular modulus of rupture (MOR) and modulus of elasticity (MOE), and the internal bond (IB) strength. In general, the surface strand layers contributed to the MOR and MOE. The parallel MOR and MOE values were the largest for the single layered S panel (only Slayers: S1), but the perpendicular MOR and MOE was the smallest. Perpendicular MOR and MOE were the largest for seven layered composite that had two cross oriented strand layers (SPSPSPS: SP7). Specimens retained more than half of their MOE and MOR after two hours in boiling water and one hour soaking. IB was the largest for the panel having only P layers, however, differences in IB strength were not identified among the other multi-layered composite panels thus the effect of layer construction on IB strength was small. Thickness swelling (TS) and surface roughness were smaller for the composite having P layers on the surface than for those having S layers. The addition of strands did not enhance the mechanical properties (MOR, MOE, IB). TS values for the panels, with which the S/P ratio was over than 1:1, was the similar to the value for the single layered S panels.

• Journal of the Korean Home Economics Association
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• v.29 no.2
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• pp.87-120
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• 1991

The purpose of this study was to identify the design characteristics of the multi-leveled chest(jang) which was the main furniture of the master bedrom(anbang) in the Chosun Dynasty. The major findings and conclusions were: 1. The front view of the multi-leveled chest were composed of a protruded top panel(kaepan), drawers, folded doors, sectional panels(chwibyok kan and morum kan) and base stand(madae) in general. Variety in the front view found more frequently in single level chests than bi- or tir-level chests. 2. The overall dimensions of each type of chest increased with increase in number of levels, but the height of the sectional parts decreased. That is, the overall proportion of the single level chests were 10 : 9, bi-level chests were 5 : 6, and tri-level chests were 2 : 3. The proportion of 1 : 1, 4 : 5, 1 : 3, 1 : 4, 1 : 5 were found often in the sectional parts such as drawers, doors, chwibyok kans and morum kans. 3. In general, the surface treatments were subtle. Carved or inlayed ornamentation were seldom seen, and most chess were finished with clear lacquer to show the natural wood grain. There were no distinctive characteristics of surface ornamentation characteristic of any one type of chest. 4. The general patterns of the metal ornaments were spade(yowidu), round, bow, rectangular(yakgua), bat and flower shapes. The multi-level chests were decorated with more metal ornament types compared with the single-level chests. 5. In conclusion, there was more variety in all the design elements in the single level chests compared with the other types of chests. The bi-and tri-level chests were quite stylized in composition, size, proportion, surface treatment, and metal ornamentation.

• Journal of Family Resource Management and Policy Review
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• v.18 no.2
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• pp.121-141
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• 2014

The purpose of this research is to determine how effective individual resources, family resources and developed environmental resources are in assisting the adaptation of a single parent's child to school life. The subjects were 284 first-year middle-school students with a single parent who were included in the first year of the Korean Children and Youth Research Panel 2010 data. The data were statistically processed using SPSS 18.0software. The results were as follows. First, the research participants' adaptation to school life, self-esteem, self-resilience, and peer relations were all shown to have an average of higher than 2 on a 4-point scale. Positive perceptions of parenting attitudes were 2.87, and negative perceptions 2.38. Computer usage was high, scoring 2.42, but mobile phone usage was average, at 2.02. Of the participants, 83.8% did not participate in a club or extracurricular activity. Second, self-esteem, self-resilience, peer relations, and positive parenting attitudes were correlated positively with adaptation to school life, but relying on a mobile phone was correlated negatively. Third, regarding the consequences of the relative effectiveness of the variables for adaptation to school life, as self-esteem, self-elasticity, and positive perceptions of parenting attitudes increased, Adaptation of a single parent's child to school life was more successful. Additionally, as annual family income and reliance on mobile phones increased, students' adaptation to school was less successful.

• The Journal of the Korea Contents Association
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• v.21 no.2
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• pp.699-706
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• 2021

This study aims to investigate the relationship between depression, drinking and social relationship satisfaction. The study also examines the moderating effect of social relationship satisfaction between depression and drinking. For these purposes, 217 single seniors with chronic diseases, excluding missing values, were finally analyzed from the 13th Korea Welfare Panel Study(KWPS). Correlation analysis, moderating analysis performed using SPSS(21.0 version). The findings of the study were as follows. First, it was identified that family relationship satisfaction among social relationship satisfaction significantly moderating the relationship between depression and drinking. Second, it was no identified that satisfaction with satisfaction with social acquaintance among social relationship satisfaction significantly moderating the relationship between depression and drinking. Based on the study results, this research suggested the practice and policy implications to increase family relationship satisfaction, especially to the single seniors with chronic diseases as well as to decrease their drinking.