• Journal of the Korea Convergence Society
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• v.12 no.5
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• pp.217-225
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• 2021

This study analyzed domestic research trends related to the behavior of problems with using smart devices in infants, focusing on addiction tendency. The main results of research trends are as follows: First, the total number of papers published per year is 79, and addiction proneness studies were published in various academic journals, while researchers' major was mostly concentrated in the department of education and social welfare. Second, there were 81 research topics, including actual conditions, scale development, related variables, interventions, and causal relationships. The proportion of research subjects was the highest with 60 (74.1%) research subjects, which are related variables. Third, the subjects of the study were divided into infants, caregivers, and teachers, and the main subjects of the study were mothers. Fourth, the research trends by research method were 73 quantitative studies (92.4%), 2 qualitative studies, 1 literature study, 2 mixed studies, and 1 other study. Fifth, the results of the analysis of influential factors were classified as risk factors and protection factors, which were specifically classified as individual factors, household factors, and social and environmental factors. Based on the study results, further discussion and practical suggestions were added.

• Research in Plant Disease
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• v.8 no.3
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• pp.184-188
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• 2002

An antagonistic bacteria, Bacillus licheniformis Nl strain which effectively inhibited mycelial growth of gray mold rot pathogen, Botrytis cinerea was isolated from the rhizosphere of perilla crop. Powder soy formulation by B. lichentfomis Nl strain as a biocontrol agent was developed far the first time and estimated its control effect on perilla leaves in this study. First of all, far the mass production of antifungal metabolites of B. lichentfomis Nl strain in flask liquid culture, the most effective carbon and nitrogen source were selected as glucose and tryp-tone, respectively, For the formulation, vegetative biomass of B. licheniformis Nl strain from 5-day-old liquid culture in nutrient broth added glucose and tryptone was mixed with soy flour, rice flour glucose, FeSo$_4$~7$H_2O$, and MnCl$_2$. 4$H_2O$, and dried and pulverized. In plastic house test, powder soy formulation effectually controlled gray mold rot as the control value of 93.1 %, was more effective than chemical fungicide, benomyl showing the control value of 86.1%. Thus, development of powder soy formulation of B. lichentfomis Nl will aid large-scale application of biological control in field trials.

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.3
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• pp.295-303
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• 2015

This paper presents the study of leakage effect due to multi-cell inflater of rapid protection system to protect the possibilities of tunnel damages by flooding threats and unusual leakage to be occurred during and after subsea tunnel construction. Particularly, this protect system should be necessary in subsea tunnel. This research concentrates the physical model tests due to several multi-cell inflater to study protection capacity of leakage between the inflater and tunnel liner. A 27:1 small scale model are used in the model tests. The leakage rate, water pressure and axial displacement of inflater are measured during the model tests. According to the results, the minium leakage rate clearly shows in the case of two-cell inflater compared with in other cases. It is concluded that the results of this research will be very useful to understand the fundamental information of inflater structure design and development the technology of tunnel protection structures in the future.

• Korean Journal of Psychosomatic Medicine
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• v.22 no.2
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• pp.71-78
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• 2014

Objectives : Behavioral and psychological symptoms of dementia(BPSD) represent significant clinical problems, resulting in functional decline, caregiver distress, institutionalization and increased mortality. A recent study showed gender differences have important role in the development of BPSD, but relationship between BPSD and gender has never been studied in Korea. This study was designed to examine whether patients with Alzheimer's disease show gender differences in behavioral and psychological symptoms of dementia(BPSD). Methods : Ninety-eight subjects with Alzheimer's disease were included in this study. We carried out history taking and cognitive assessment for the diagnosis of Alzheimer's disease based on DSM-IV. Cognitive impairment and BPSD were measured using the Mini Mental State Examination(MMSE), Global Deterioration Scale (GDS), Clinical Dementia Rating(CDR) and the Korean Neuropsychiatric Inventory(K-NPI). Independent samples t-test was used to examine the differences across gender in BPSD. Correlation analysis between MMSE, CDR, GDS and NPI was performed using Pearson's correlation coefficient. Results : There were no significant gender differences between the gender in BPSD. We found statistically significant negative correlations between MMSE with NPI total score, and with scores of several sub-domains such as hallucination. Conclusions : This study showed that gender differences in BPSD are not significant. Further research is necessary to identify whether BPSD affect gender differences or individual differences.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3427-3435
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• 2012

Beginning with retirement in 2010 of the leading group of baby boomer generation born in 1955, baby boomers are starting to retire from work in full-scale. Since retirement of baby boomers refers to increase in the senior class with longer life expectancies caused by development of medical technologies, enhancement of living standards, and improvement of surrounding environments, annually decreasing birthrate is further accelerating entry of our society into an aged society. Accordingly to examine baby boomer generation's preparation for retirement in relation to career self-efficacy, first, difference in retirement preparation according to mean monthly income and current occupation was analyzed. Second, the effect of career self-efficacy on retirement preparation was studied. The survey for this study was conducted for one month between January 17 and February 16, 2012 in Seoul, Gyeonggi, Gangwon, Chungnam, Gyeongnam, Jeonnam, and Jeju. 500 surveys were distributed to baby boomer generations through direct visit and mail, among which 443 responses were returned. 400 effective responses were selected as subjects of the study. As a result, preparation for retirement according to mean monthly income was verified to be significant in terms of economic and physical factors. Significant results were shown in all factors including economic, physical and social factors for retirement preparation according to current occupation. Career self-efficacy had greatest influence of 58% on retirement preparation with economic factors. It also influenced all factors including self assessment, objective setting, occupational information, and problem solving.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.78-78
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• 2002

The role of heat shock proteins in shielding organism from environmental stress is illustrated by the large-scale synthesis of these protein by the organism studied to date. However, recent evidence also suggests an important role for heat shock protein in fertilization and early development of mammalian embryos. Effects of elevated in vitro temperature on in vitro produced bovine embryos were analysed in order to determine its impact on the expression of heat shock protein 70 (HSP70) by control and frozen-thawed after in vitro fertilization (IVF) or nuclear transfer (NT). The objective of this study was to assess the developmental potential in vitro produced embryos with using of the various containers and examined expression and localization of heat shock protein 70 after it's frozen -thawed. For the vitrification, in vitro produced embryos at 2 cell, 8 cell and blastocysts stage after IVF and NT were exposed the ethylene glycol 5.5 M freezing solution (EG 5.5) for 30 sec, loaded on each containers such EM grid, straw and cryo-loop and then immediately plunged into liquid nitrogen. Thawed embryos were serially diluted in sucrose solution, each for 1 min, and cultured in CRI-aa medium. Survival rates of the vitrification production were assessed by re-expanded, hatched blastocysts. There were no differences in the survival rates of IVF using EM grid, cryo-loop. However, survival rates by straw were relatively lower than other containers. Only, nuclear transferred embryos survived by using cryo-loop. After IVF or NT, in vitro matured bovine embryos 2 cell, 8 cell and blastocysts subjected to control and thawed conditions were analysed by semiquantitive reverse transcription polymerase chain reaction methods for hsp 70 mRNA expression. Results revealed the expression of hsp 70 mRNA were higher thawed embryos than control embryos. Immunocytochemistry used to localization the hsp70 protein in embryos. Two, 8-cell embryos derived under control condition was evenly distributed in the cytoplasm but appeared as aggregates in some embryos exposed frozen-thawed. However, under control condition, blastocysts displayed aggregate signal while Hsp70 in frozen-thawed blastocysts appeared to be more uniform in distribution.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.6
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• pp.610-616
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• 2012

All the countries in the world is currently facing the full scale of energy-climate era currently, and making strong energy policy that will lead to green growth of the future energy resources by utilizing renewable energy as the basis of entering the advanced country becomes the goal of development that satisfies the demand for energy in 21st century. Recently, ocean energy attracted the attention along with the necessity of developing renewable energy. Ocean energy is the one of most prominent recyclable and clean resources that has not been developed yet. So, it is highly required to develop good tidal current energy conversion system in coastal area. The inflow angle that acts against tidal current turbine, seabed effect and the change of efficiency along the occurrence of cavitation were investigated through the wake flow characteristics in this study. Power coefficient degradation by seabed effect did not appear in the condition of this calculation. Efficiency degradation appeared from above $10^{\circ}$ regarding inflow angle and power coefficient was calculated as lower by 7 % at $45^{\circ}$. Torque and power coefficient increased as inflow velocity rose, but power coefficient degradation appeared from above 3m/s when the cavitation happened. So, it was recognized that the larger inflow angle and occurrence of cavitation become the reason for power degradation through the flow characteristics.

• Culinary science and hospitality research
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• v.15 no.2
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• pp.150-160
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• 2009

This study analyzed the quality characteristics of demi-glace sauce with different addition of roux which is usually used as a thickener. The trust level and acceptability for commercial demi-glace sauce were surveyed in order to draw the visual idea and direction for the development of large scale commercial production of demi-glace sauce. Also, the optimal level of salt and roux content in the sauce was determined with various cooking conditions. As the roux content increased, the color became light and the viscosity of the sauce increased while pH, salinity and brix were not affected much by amount of roux. The professional chefs as well as general sensory panel preferred the demi-glace sauce prepared with 9% roux. To sum up, it can be claimed that the optimal conditions established in this study for commercial production of demi-glace sauce ensure the desired quality and economic feasibility.

• Journal of Aquaculture
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• v.13 no.4
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• pp.325-330
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• 2000

For development of all male seed production at hatchery scale, a comparative study was made on the seed production traits of supermale (IT - t) and superfemale (IT - L1 ~) Nile tilapia, Oreochromis niloticus. Supermales were crossed with normal females (XX- f) and the superfemales with normal males (XY - t ) or sex reversed males (XX- L1 t); progeny survival of these crossings and sex ratio were evaluated. Hatching success of the eggs, fertilized by the supermale was significantly lower than that by the normal male. Over 95-99 % progenies sired by crossing supermales with normal females were males, while 52-55 % progenies alone were males with the cross of normal males and normal females. Hatching success and survival of alevins were significantly higher for the progenies of the crosses between superfemales and sex reversed males than those resulting from the crosses between superfemales and normal males. However, there was no significant difference in the sex ratio among the progenies of these crosses. Therefore, crossings of superfemales with sex reversed males provide the highest percentage of survival and male progenies.

• Applied Chemistry for Engineering
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• v.25 no.1
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• pp.1-13
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• 2014

Lithium ion batteries (LIBs) are the state-of-the-art technology among electrochemical energy storage and conversion cells, and are still considered the most attractive class of battery in the future due to their high specific energy density, high efficiency, and long cycle life. Rapid development of power-hungry commercial electronics and large-scale energy storage applications (e.g. off-peak electrical energy storage), however, requires novel anode materials that have higher energy densities to replace conventional graphite electrodes. Germanium (Ge) and silicon (Si) are thought to be ideal prospect candidates for next generation LIB anodes due to their extremely high theoretical energy capacities. For instance, Ge offers relatively lower volume change during cycling, better Li insertion/extraction kinetics, and higher electronic conductivity than Si. In this focused review, we briefly describe the basic concepts of LIBs and then look at the characteristics of ideal anode materials that can provide greatly improved electrochemical performance, including high capacity, better cycling behavior, and rate capability. We then discuss how, in the future, Ge anode materials (Ge and Ge oxides, Ge-carbon composites, and other Ge-based composites) could increase the capacity of today's Li batteries. In recent years, considerable efforts have been made to fulfill the requirements of excellent anode materials, especially using these materials at the nanoscale. This article shall serve as a handy reference, as well as starting point, for future research related to high capacity LIB anodes, especially based on semiconductor Ge and Si.