• Journal of the Korean Society of Child Welfare
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• no.56
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• pp.195-220
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• 2016

The purpose of this study was to compare between two-parent and single-parent families the relationship between perceived parental monitoring/affection and adolescent offline/online delinquency. we analyzed 1,812 cases of high school students (1,628 cases of two-parent families and 184 cases of single-parent families) using the $4^{th}$-and $5^{th}$-year data from the 'Korean Children and Youth Panel Survey'. We used structural equation modeling to understand the correlation between variables, and conducted multi-group analysis to confirm the distinction between family structures. The results of the study were as follows. First, perceived parental monitoring influenced offline adolescent delinquency only among two parent families, while perceived parental affection did not influence either family type. Second, perceived parental affection influenced online adolescent delinquency only among single-parent families, and the path also had a greater negative effect than two-parent families. In the case of perceived parental monitoring, it did not influence online adolescent delinquency regardless of family type, but the path had a greater negative effect on two-parent families than single-parent families. Based on these results-, more concrete social-welfare practical and political implications about adolescent delinquency proposed.

• Korean Journal of Social Welfare Studies
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• v.45 no.2
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• pp.5-30
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• 2014

This study sought to identify developmental trajectories of bullying victimization from late elementary school through early high school, and to examine internalizing and externalizing problem outcomes associated with the trajectory group membership. Data from Seoul Panel Study of Children were collected annually over a 7-year period from 5th grade of elementary school through 2nd grade of high school (2005~2011). Latent class growth analysis yield three trajectory classes corresponding to stable low (81.2%), stable high (3.5%), and declining bullying victimization (15.6%). Findings from analysis of covariance indicated that students in both stable high and declining trajectory groups reported significantly higher means in internalizing behavior (withdrawal, depression/anxiety, and suicide ideation), compared to those in the stable low group. For externalizing behavior such as aggression and juvenile status offense, students in the stable high group showed higher means, compared to those in the stable low and declining trajectory groups. Developmental pattern of bullying victimization over multiple development stages and associated internalizing and externalizing outcomes are discussed as are the implications for the bullying prevention.

• Journal of the Korean Society of School Health
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• v.18 no.1
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• pp.47-58
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• 2005

Purpose:　This study is a descriptive correlation survey with the purpose of identifying the relationship between family function and hope in adolescents. It was done to provide basic data for developing family centered nursing strategies to promote adolescents' hope. Methods: The subjects of this study were 1030 high school students in J city. Data were analyzed with SPSS 10.0 program. Frequencies and percentages were used to compare the subjects' general characteristics. Minimum values, maximum values, mean scores and mean grades were used to identify the level of family function and hope. Pearson's correlation coefficient was used to analyze the relationship between family function and hope in adolescents, and t-test, ANOVA, and Scheffe test were used to examine the level of family function and hope by general characteristics. Results:　1. The level of adolescents' family function ranged from 26 to 97, the mean score was 66.85$\pm$13.16, and the mean grade was 2.76$\pm$0.52. 2. The level of adolescents' hope ranged from 55 to 153, the mean score was 111.48$\pm$17.64 and the mean grade was 2.78$\pm$0.44.　3. It showed that there is a significantly positive correlation (r=0.546, p=.000) between adolescents' family function and hope. That is, the better family function adolescents have, the higher level of hope they have. 4. Adolescents' family function showed significant differences according to school record (F=6.363, p=.002), school life satisfaction (F=4.922, p=.007), father's education (F=2.640, p=.048), mother's education (F=3.586, p=.013) and domestic economy status(F=3.022, p=.049).　5. Adolescents' hope showed significant differences according to religion (t=2.018, p=.044), school type (t=2.567, p=.010), school record (F=9.712, p=.000), school life satisfaction (F=11.367, p=.000), father's education (F=4.632, p=.003), mother's education (F=4.709, p=.003), domestic economy status (F=4.235, p=.015), relationship with friends (F=8.187, p=.000), and subjective health condition (F=5.490, p=.001). Conclusion: First, in order to improve adolescents' family function, which encourages hope in adolescents, it is necessary to develop nursing interventions and to make further studies.　Second, it is necessary to develop instruments for improving Korean adolescents' family function and hope. Third, further studies are required to improve adolescents' family function and hope in special situations such as disease, drug abuse and juvenile delinquent.

• Journal of Sericultural and Entomological Science
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• v.32 no.1
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• pp.31-37
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• 1990

For fine-denier cocoon filament production, the precocious trimolting silkworms were induced by the treatments with both the imidazole compound "KK-42" hating anti-juvenile hormone activity and high temperature, and their growth, dietary efficiency, cocoon and cocoon filament qualities were compared with those of normal tetramolters as control. 1. The percentage of precocious trimolters was higher in the application of KK-42 than the treatment of high temperature. The effective concentration of KK-42 was 10$\mu\textrm{g}$/1arva. The high temperature treatment for 48 hour was more effective than 36 hour treatment, and silkworm larvae fed on mulberry leaves were more sensitive than artificial diet to induce trimolters. 2. The larval duration of the trimolters induced by KK-42 was 5.17 day shorter than that of normal tetramolters in mulberry leaves rearing, and the increasing pattern of body weight in the 4th inster larvae of trimotlers was similar to the 5th instar larvae of normal tetramolters. 3. The qualities such as cocoon weight, cocoon layer weight and cocoon layer ratio of precocious trimolter induced by KK-42 were much lower those of normal tetramolters: the cocoon weight and cocoon layer ratio were 0.78g, 14.2cg and 18.4% in mulberry leaves rearing, and 0.86 cg, 10.3cg and 12.3% in artificial diet rearing, respectively. 4. The size of cocoon and cocoon filament was smaller in the precocious trimolter, both KK-42 and high temperature, as compared with that of the normal tetramolters. 5. The efficiency of cocoon layer production of the precocious trimolters by the KK-42 was lower than that of the normal tetramolters: amount of the cocoon layer production per 1g of dry mulberry leaves ingested was 7.97cg in the precocious trimotors, while 9.20cg in the normal tetramolters.

• Journal of Sericultural and Entomological Science
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• v.43 no.2
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• pp.77-82
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• 2001

This study was investigated to know the effects of diflubenzuron(DFB) on the larval silkgland development of the silk-worm, Bombyx mori (L.). It has been known as a prohibitor of chitin synthesis mostly on the species of the Order Lepidoptera. In this work, the effects of the DFB concentrations (2.5$\times$10$\^$-1/,2.5$\times$10$\^$-2/, and 2.5$\times$10$\^$-3/$\mu\textrm{g}$/$\mu$l on the various larval stages, were investigated in terms on the silkgland. The macro- and microstructure of cell membrane of silkgland, and the differences of silkgland weight and water contents treated by DFB are also surveyed. As the tesults, the silkgland weight depended sensitively on not the DFB concentration but the DFB treatment period. The longer DFB treatment period, the lighter dried silkgland weight and the heavier water content of the silkgland. White opaque(WO) emerged in the middle silkgland of DFB treated larva. From the scanning election microscope observation, the cell membrane of silkgland of DFB treated larva was distinctly more compact compared to that of control. The WO was evidently resulted from the obstacles of normal transformation of silk protein through the cell membrane of middle silkgland.

• Korean Journal of Environmental Biology
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• v.39 no.3
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• pp.344-353
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• 2021

Juvenile olive flounder, Paralichthys olivaceus (mean weight 66.7±7.1 g; mean length 19.2±0.9 cm) in a bio-floc environment were exposed to microplastic (PE: polyethylene, size 40-48 ㎛) at 0, 4, 20, 100, 500 and 2,500 mg L^-1 for 96 hours. No P. olivaceus deaths were observed following microplastic exposure. In the plasma components, calcium was significantly decreased whereas there was no significant change with magnesium following microplastic exposure. Glucose was significantly decreased with over 100mg L^-1 at 48 hours and 20mg L^-1 at 96 hours. Cholesterol was significantly decreased with over 20mg L^-1 after 48 hours, whereas there was no significant change in the total protein content. In enzymatic plasma components, the AST(Aspartate aminotransferase) was significant decreased by microplastic exposure. The results of this study indicate that acute exposure to microplastic induces blood physiological changes in P. olivaceus.

• Journal of Korea Port Economic Association
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• v.37 no.1
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• pp.1-18
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• 2021

A coastal marine ranching project in Uleungdo had been conducted for 5 years from 2013 to 2017 with investment costs of 5 billion won, for the special purpose of the deployment of artificial reefs, the release of young fishes. The paper focuses on an ex-post analysis of the economic feasibility for the project after completing the project, which is apart from a preliminary viability. For economic analysis, the economic benefits are derived from direct benefits including increasing effects of fisheries income and saving effects of harvesting costs, and indirect benefits including increasing effects of recreational fishing and preservation effects of coastal marine ecosystems while economic costs include releasing and purchasing costs of artificial reef and juvenile fish, R&D costs, maintenance costs and harvesting costs. The result shows that the project should not be accepted according to NPV=-0.125 billion won, IRR=4.5% and B/C ratio=0.98 under Scenario 1 which considers direct benefits and indirect benefits excluding the preservation values, while the project should be accepted under Scenario 2 indicating NPV=30.9 billion won, IRR=11.3% and B/C ratio=1.49 which considers the direct benefits as well as the indirect ones including the preservation values, based on 4.5% of the social rate of discount.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.2
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• pp.134-140
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• 2019

A feeding trial was conducted to investigate the effects of dietary fish meal replacement by a blend of lysine cell mass, corn protein concentrate and poultry by-product meal on the growth and blood chemistry of the starry flounder Platichthys stellatus. The fish meal replacer (FMR) was prepared to have the same level of protein as fish meal (FM). With a commercial diet as a positive control, five experimental diets (basal, FM42, FM32, FM22 and FM12) were formulated to contain 52% protein and 10% lipid. The dietary FM levels decreased from 52% (basal) to 42, 32, 22 and 12% with concomitant increase in the FMR to 10, 20, 30, 40 and 50%, respectively. Juvenile starry flounder with an average body weight of 177.3 g were randomly distributed in each (30 fish/tank) of 18 plastic tanks ($139{\times}99{\times}54cm$). After a 45-day feeding trial, the survival rate ranged from 95.6% (FM22) to 100% (control and FM42), while the weight gain of the fish groups varied from 49.7 to 58.4 g. The results clearly revealed that starry flounder can grow well on a diet containing low FM (12%) with a high level of FMR (50%) without any adverse effects.