• Electronics and Telecommunications Trends
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• v.22 no.6
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• pp.40-50
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• 2007

본 고에서는 이기종 네트워크 환경에서의 심리스 핸드오버 기술에 대한 기술 분석 및 관련 표준화 동향에 대하여 기술한다. 이기종 네트워크에서의 심리스 핸드오버 기술로 대표적인 IEEE 802.21 Working Group에서 표준화를 진행해온 Media Independent Handover 기술에 대한 참조 모델, 서비스, 프로토콜 및 이기종 네트워크간 핸드오버 절차를 중심으로 살펴본다. 최근 표준화 동향 파악을 위해서 2007년 10월 기준으로 IEEE 802.21 Working Group 및 IEEE 802.11u Task Group의 표준화 현황과 핵심 이슈를 정리하며, 그간 3GPP 표준과 연계한 MIH 기술 적용 현황 및 향후 추진시 고려할 사항에 대하여 기술한다. 또한, IEEE 802.21 Working Group 내 신규 그룹인 Multi-Radio Power Conservation Management Study Group과 Security Study Group의 진행상황에 대하여 살펴본다.

• Safety and Health at Work
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• v.11 no.2
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• pp.228-234
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• 2020

Background: The concept of social capital has its focus on cooperative relations in the workplace. This study investigates the association between social capital and sickness absence among workers in 41 work groups in the Danish dairy industry and examines the possible effects of an intervention on social capital in the workplace on sickness absence. Methods: A sample of 791 dairy workers working in 41 work groups that participated in an intervention study on social capital filled in a questionnaire on four subtypes of social capital, and social capital scores from individual participants were aggregated to the level of work groups. Sickness absence was measured at the level of work groups in company registers as the two-year average percentage of working time lost to sickness absence. Group-level associations between social capital and sickness absence were analyzed using multilevel linear regression analysis. Analyses were adjusted for age, gender, group size, and random effects at the workplace level. Results: We found statistically significant associations between social capital within work groups, social capital in relation to the immediate manager, and social capital toward the workplace as a whole on the one side and sickness absence on the other side. We found no support for any effects of the intervention on sickness absence. Conclusion: The work group level of social capital is associated with the work group level of sickness absence. However, the intervention to enhance group-level social capital had no effect on reducing sickness absence in the intervention group.

• Journal of Technologic Dentistry
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• v.12 no.1
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• pp.15-21
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• 1990

This research was to investigate and study on 92 Dental Technicians who had had some experience of working or being employed at dental craft-shops or craft-rooms in Seoul area and had transferred to other types of occupation, with regard to their reasons for changing their profession. For an approach to the study, some questionnaires and interview including 3 aspects of in quiriesmental, economic and social backgrounds-were administered, and major findings are as follows ; 1. The ages in which transferring to other kinds of job happened occurred mostly from 20 to 30(78.26%) an a group of subjects whose ages ranged from 20 to 30 years old. And, with regard to their experience of working or being employed at dental craft-shops or craftrooms, the transfer of their profession to the other kinds mosty happened in a group of subjects(94.56%) whose experience of working in the dental field is less than 4 years. 2. The reason of transfer with reference to the mental background was mostly mattered in a group that expressed "Excessive Work Duties"(34.78%), and most lowly mattered in a group of subjets who had "Certain Relations with Dentists"(8.70%). Thus, it appeared that the biggest reason of transfer by the mental background was, due to the excessive duty work, not to have Sufficient time to be usualized by dental technicians for their own purpose. 3. With reference to the economical background, a group that declared there was "No Wage Standards in Ratio to Their Labor" was the most in the separation rate as shown 45.56%. And, a group suspecting "No Guarantee for Their Living after Retirement" Showed a separation rate, 9.78%. In other words, the reason for transfer was that they did not receive due wage according to their amount of labor. 4. With reference to the social background, a group making a subject for no good working environments or conditions had a separation rate, 41.30%, which was the most among others, and a group with a subject of "The Rarity of Employment because of Excessive Supply of Dental Technicians" had the rate, 10.87%, which was the lowest. This meant that the major cause of transfer by the social background was a phenomenon for dental technicans to escape from unclean working places.

• Biomedical Science Letters
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• v.10 no.4
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• pp.453-457
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• 2004

The welders and car painters are frequently exposed to heavy metals such as lead, zinc, cadmium and chromium, and those are a major source of heavy metal poisoning. This study was carried out to investigate the relationship of the heavy metal level in blood by age, working duration, and smoking status among 105 industrial workers and 88 general people in Gyeongnam province from October 2003 to October 2004. The heavy metal level in blood was analyzed by atomic absorption spectrophotometer. Mean blood lead level in exposed group and control group was 8.40±4.67μl/dl, 1.82±1.35μl/dl, respectively. Mean blood zinc level in exposed group and control group was 9.43±5.38 ㎍/ml, 2.89±1.79㎍/ml, respectively. Mean blood cadmium level in Exposed group and control group was 1.53±1.05μl/dl, 0.60±0.49 μl/dl, respectively. Mean blood chromium level in exposed group and control group was 0.89±0.76μl/dl, 0.68±0.63μl/dl, respectively. Lead, zinc, cadmium and chromium level in blood of exposed group was significantly higher than that of control group. In the comparison of smoking status, lead, zinc and cadmium level of smoker's was significantly higher than that of non-smoker's. Comparison of heavy metal level by age, lead, zinc, cadmium level in 40's, 50's (exposed group) in blood significantly higher than that of 20's, 30's. In exposed group, working duration has no significant difference. In conclusion, smoking was the most hazardous factor to elevate in blood heavy metal levels.

• Human Ecology Research
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• v.55 no.1
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• pp.13-26
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• 2017

This study investigated the latent groups depending on married working women's work-family spillover. The effects of factors that determine mental health subgroups and differences were also analyzed. Mixture modeling was applied to the Korean Longitudinal Survey of Women & Families to achieve the research objectives. The major findings of this study were as follows. First, there were four subgroups that could be defined according to the work-family spillover: mid-level spillover group (mid-positive and mid-negative spillover group), high-level spillover group (high-positive and high-negative spillover group), low-level spillover group (low-positive and low-negative spillover group), and high-negative and low-positive spillover group. Second, the results of mixture regression analysis to test the effect of eco-system variables showed that age, academic background, non-traditional family value, number of children, work hours, wage income, and availability of the maternity leave were significant determinants of the latent groups. The probability of classifying in the high-negative and low-positive spillover group increased when women showed a lower academic background and wage income, higher number of children and older age, and longer work hours than others. Third, the high-level spillover group, and the high-level spillover group showed the lowest stress and the lowest depression; however, the low-level spillover group reported the highest stress and the highest depression. Implications, limitations, and future directions were discussed based on the results.

• Korean Journal of Child Studies
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• v.38 no.2
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• pp.107-117
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• 2017

Objective: Whereas some studies have suggested that source monitoring is significantly associated with working memory and inhibitory control, both of which are components of executive functioning, other studies have argued otherwise. The author of this study determined that such contradictory findings are a result of heterogeneity in the assessment methods for source monitoring. Therefore, this study aimed at exploring whether the relationships among source monitoring, working memory, and inhibitory control may be altered depending on the differences of source recall conditions. Methods: Eighty children aged 5-8 years saw interesting activities via two different sources. Their source memories on the activity were assessed subsequently. The children were assigned to either the "continuous" source recall group or "non-continuous" source recall group. Both groups participated in working memory and inhibitory control tasks. Results: The results showed that working memory was significantly related to source monitoring regardless of the condition of source recall (continuous vs non-continuous). On the other hand, inhibitory control was significantly associated with source monitoring only in the non-continuous source recall group. Conclusion: Based on these results, the author discussed the need to consider the conditions of source recall during investigative interviews with children in order to induce accurate source monitoring, as part of our effort to interpret the inconsistency of results in the literature and to draw potential applications.

• Journal of Family Resource Management and Policy Review
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• v.20 no.3
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• pp.25-43
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• 2016

This study focused on the time use of a dual-earner working group with preschool children on working and nonworking days using 2014 time-use survey data provided by Statistics Korea(KOSTAT). We collected the time-use data recorded in a 2,158 time diary. We divided the time use into 4 parts ; paid work, household labor work (including caring work), leisure and living essentials. For the statistical analysis, we used SPSS 18.0 packages, i.e., descriptive statistics, T-test, Anova with Duncan test and regression for the impact off the independent factors. The results verified gender differences in time use and recognized the usefulness of the time-allocation analysis for the diagnosis of Work and Life Balance(WLB). In the conclusion, we suggest increasing men's time allocation for household labor as a crucial solution to the WLB of dual-earner working groups. And the follow-up study should include the various factors that affect the time allocation of dual-earner groups, such as type of labor and job and children's ages.

• Korean Journal of Biological Psychiatry
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• v.22 no.2
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• pp.63-77
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• 2015

Objectives The combination extract of four kinds of herbs, Gastrodia elata, Liriope platyphylla, Dimocarpus longan, and Salvia miltiorrhiza, has shown to have memory improving effects in mice. The aim of this study was to investigate the efficacy and safety of the herbal mixture for improving working memory as well as microstructural changes in white matter integrity in individuals with subjective memory complaints. Methods Seventy-five individuals with subjective memory complaints were assigned to receive either placebo (n = 15) or herbal mixture (low-dose group, n = 30 and high-dose group, n = 30) supplementation in an 8-week, randomized, double-blind, placebo-controlled clinical trial. Changes in working memory performance and fractional anisotropy (FA) values reflecting white matter integrity from baseline to 8-week endpoint were assessed. Results The herbal mixture group showed an increase in working memory performance compared to the placebo group (p for interaction = 0.001). In addition, the herbal mixture group showed an increase in FA values in the temporo-parietal regions (corrected p < 0.05), which are crucially involved in working memory function and are among the most affected regions in patients with cognitive impairments. Conclusions Findings from this study indicate that the herbal mixture may be a promising therapeutic option for individuals with subjective memory complaints.

• Human Ecology Research
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• v.53 no.5
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• pp.475-488
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• 2015

Economic activity and social participation by women has recently increased; however, working mothers raising young children are under new stress due to the simultaneous combination of job and parenting responsibilities. This stress has resulted in social problems of career break and low fertility. This study investigates the effect of clinical art therapy on occupational stress and parenting stress of working mothers. We analyzed 34 working mothers in full-time employment (over 8 hours a day) who have preschool children (0-6 years old). They were divided into 17 subjects in the experimental group and 17 subjects in the control group. For the experimental group, 10 hours and a half sessions of group art therapy were participated in once a week from April to August in 2014. We perform Dan Occupational Stress Index by Ivancevich and Matteson, Parenting Stress Index/Short Form and salivary cortisol test before and after the group art therapy. For qualitative analysis, Kinetic House-Tree-Person (KHTP) drawing test was used. Using SPSS ver. 19.0, paired t -test or Wilcoxon signed rank test compared the pre and post analysis results. The results of this study are as follows. First, scores of 'occupational stress factor' subpart showed significant improvement in the Occupational Stress Index after the clinical art therapy. Second, scores of 'parental distress,' 'parent-child dysfunctional interaction,' and 'difficult child' subpart in Parenting Stress Index also showed a significant improvement. Third, a positive change was observed after the clinical art therapy in the KHTP drawing test. In conclusion, this study suggests that the clinical art therapy can be effective for occupational stress factors and the parenting stress of working mothers.

• Korean Journal of Biological Psychiatry
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• v.17 no.2
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• pp.70-78
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• 2010

Objectives : This study investigated the differences of working memory among the subtypes of ADHD. Methods : Eighty-one children and adolescents with ADHD and thirty normal controls were recruited. Children with any cognitive disorders and low intelligence were excluded. In order to evaluate the verbal and visuospatial working memory, Digit span and Finger windows tasks were measured, respectively. Performances on these measures between children with ADHD and controls were compared. Further, performances among the groups of ADHD predominantly inattentive(ADHD-IA)(n=40), predominantly hyperactive-impulsive(ADHD-HI)(n= 10), and combined type(ADHD-C)(n=31), were compared. Results : Scores of Finger windows forward task were lower in the ADHD group as compared to the control group, whereas, the Digit span forward showed no difference. Both scores of Digit span backward and Finger windows backward task were lower in the ADHD group than the controls. Children with ADHD-IA performed poorer than children with ADHD-C on the Finger windows backward task. Conclusion : The results of this study showed that children with ADHD have deficits in spatial short-term memory and verbal and visuospatial working memory when compared to normal children. The deficits were evident in children with ADHD-IA subtype and in particular, performance on the visuospatial working memory task in this group was poorer than the ADHD-C group.