• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.2
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• pp.131-137
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• 2005

Protective relays provide important features to electrical power systems for protecting against faults and consequent short circuits. This research presents a novel VLSI design of the digital protective relay, which overcomes today's uP/DSP-based relays. This design features good cancellation of DC/k-th harmonic components, noticeable not performance and flexible Protection behavior in the minimized core area The proposed design was successfully implemented by a FPGA(Field Programmable Gate Array) device and can concurrently process over 16KSPS at less $0.03[\%]$ error rate.

• Nuclear Engineering and Technology
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• v.53 no.3
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• pp.825-832
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• 2021

A simulation-based approach is proposed to study the protective actions taken by residents during nuclear emergencies using cognitive findings. Human perception-based behaviors are not heavily incorporated in the evacuation study for nuclear emergencies despite their known importance. This study proposes a generic framework of perception-based behavior simulation, in accordance with the ecological concept of affordance theory and a formal representation of affordance-based finite state automata. Based on the generic framework, a simulation model is developed to allow an evacuee to perceive available actions and execute one of them according to Newton's laws of motion. The case of a shadow evacuation under nuclear emergency is utilized to demonstrate the applicability of the proposed framework. The illustrated planning algorithm enables residents to compute not only prior knowledge of the environmental map, but also the perception of dynamic surroundings, using widely observed heuristics. The simulation results show that the temporal and spatial dynamics of the evacuation behaviors can be analyzed based on individual perception of circumstances, while utilizing the findings in cognitive science under unavoidable data restriction of nuclear emergencies. The perception-based analysis of the proposed framework is expected to enhance nuclear safety technology by complementing macroscopic analyses for advanced protective measures.

• Physical Therapy Korea
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• v.30 no.1
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• pp.78-85
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• 2023

Background: Despite fall prevention strategies suggested by researchers, falls are still a major health concern in older adults. Understanding factors that differentiate successful versus unsuccessful balance recovery may help improve the prevention strategies. Objects: The purpose of this review was to identify biomechanical factors that differentiate successful versus unsuccessful balance recovery in the event of a fall. Methods: The literature was searched through Google Scholar and PubMed. The following keywords were used: 'falls,' 'protective response,' 'protective strategy,' 'automated postural response,' 'slips,' 'trips,' 'stepping strategy,' 'muscle activity,' 'balance recovery,' 'successful balance recovery,' and 'failed balance recovery.' Results: A total of 64 articles were found and reviewed. Most of studies included in this review suggested that kinematics during a fall was important to recover balance successfully. To be successful, appropriate movements were required, which governed by several things depending on the direction and characteristics of the fall. Studies also suggested that lower limb muscle activity and joint moments were important for successful balance recovery. Other factors associated with successful balance recovery included fall direction, age, appropriate protective strategy, overall health, comorbidity, gait speed, sex and anticipation of the fall. Conclusion: This review discusses biomechanical factors related to successful versus unsuccessful balance recovery to help understand falls. Our review should help guide future research, or improve prevention strategies in the area of fall and injuries in older adults.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.67-68
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• 2002

The properties and mechanism of silicon protuberance and groove processing by diamond tip sliding using atomic force microscope (AFM) in atmosphere were studied. To control the height of protuberance and the depth of groove, the processed height and depth depended on load and diamond tip radius were evaluated. Nanoprotuberances and grooves were fabricated on a silicon surface by approximately 100-nm-radius diamond tip sliding using an atomic force microscope in atmosphere. To clarify the mechanical and chemical properties of these parts processed, changes in the protuberance and groove profiles due to additional diamond tip sliding and potassium hydroxide (KOH) solution etching were evaluated. Processed protuberances were negligibly removed, and processed grooves were easily removed by additional diamond tip sliding. The KOH solution selectively etched the unprocessed silicon area. while the protuberances, grooves and flat surfaces processed by diamond tip sliding were negligibly etched. Three-dimensional nanofabrication is performed in this study by utilizing these mechanic-chemically processed parts as protective etching mask for KOH solution etching.

• Journal of The Korean Society of Integrative Medicine
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• v.5 no.4
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• pp.49-55
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• 2017

Purpose : In this study we tested the hypothesis that eucommia ulmoides (EU) extract would improve disuse-induced muscle atrophy following hindlimb immobilization. Method : The hindlimb immobilization was performed with casting tape to keep the left ankle joint in a fully extended position. The rats in EU treated group were orally administrated with eucommia ulmoides water extract. After 2 weeks of immobilization, all animals were sacrificed, and the whole gastrocnemius muscles were dissected from both legs. The morphology of right and left gastrocnemius muscles in both EU and control groups were assessed by hematoxylin and eosin staining. Results : Eucommia ulmoides extract represented the significant protective effects against the reductions of the gastrocnemius muscles weight and average cross section area to compared with Control group. Conclusion : Eucommia ulmoides has protective effects against immobilization induced muscle atrophy.

• Proceedings of the KIEE Conference
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• 2006.11a
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• pp.12-14
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• 2006

This paper presents an vulnerability index for hidden failure of protective relays in transmission system. The bad influence can be quantized by an vulnerability index. When there is mis-operation, no-operation or mis-setting, power flow can be quantized by an index. According to the index, relays can be resetting. So the wide area blackout can be prevented.

• Journal of the Korean Home Economics Association
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• v.44 no.6 s.220
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• pp.15-22
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• 2006

The purpose of this study was to investigate the relationship between early childhood teacher's knowledge and protective practice on safety. The study subjects were 312 early childhood teachers working at kindergartens and day care centers in Seoul, Kyung-gi area. A modified questionnaire was based on that developed by Nam(2002). Data were analysed by t-test, One-way ANOVA, and Pearson's correlations. The results were as follows. First, there was a small but insignificant difference for safety knowledge in the teachers' teaching experiences, and working place, but no difference in attending safety education. Second, there were differences for safety practices in teaching experiences and working place. Third, teachers' safety knowledge was highly and positively correlated with safety practices. In conclusion, enhanced early childhood teacher' safety knowledge is needed for improved safety practice.

• Korean Journal of Rural Living Science
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• v.6 no.1
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• pp.25-30
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• 1995

This study was designed to obtain the basic data developing the UV ray protective garments for the plastichouse workers. Two subjects were volunteered for 1hr. wear test in plastic house, and the ensembles was composed of one of three kinds blouse (UV blocking blouse, polyester/cotton 47/53 blouse, and polyester blouse), shorts, sleeveless undershirts, pants and socks. The measurements were rectal temperature, skin temperature, microclimate inside clothing, subjective sensation, and the colour difference of UV sensor. The results were as follows: 1. Microclimate especially, temperature inside clothing of polyester blouse was the highest among the garments. And UV-proof polyester blouse showed the lower mean skin temperature and microclimate than others. Showing the highest sweat volume. 2. No significant difference on UV ray blocking function among 3 kinds of garment was shown. 3. We could conform that in spring for the plastic house wぉw s garment low thermal insulating value and wide covering area were more important factors than UV blocking function of fabric.

• The Research Journal of the Costume Culture
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• v.17 no.5
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• pp.834-848
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• 2009

The purpose of this study is to analyse the research trends and to find a future direction in the area of clothing construction in Korea. The data were included articles on clothing construction published in the five major journals from 2000 through 2008 in Korea. The identified 513 articles were categorized in eight areas: design related clothing construction, study of body types, study of patterns, size of apparel, fitting of clothing, protective clothing and functional clothing, sewing and the others. In the results of examining the percentage of articles on clothing construction among articles published in each journal, the percentage of articles on clothing construction was highest as 21.2% in the Journal of Korean Home Economics and next, 19.3% in the Research Journal of the Costume Culture. As to the percentage of research on clothing construction according to theme, research on protective clothing and functional clothing were largest as 28.2%, and next, research on body types as 18.9%, and research on garment size systems as 10.5%. Research on protective clothing has increased remarkably since 2000, and particularly in 2004 it was so active that it occupied 44.1% of research on clothing construction. Next, with regard to the subjects of research, research with female subjects was more frequent than that with male subjects according to gender, and research with men and women in their twenties was most frequent according to age. These results show somewhat unbalanced tendencies in terms of research subjects.

• Journal of the Korean Dietetic Association
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• v.13 no.3
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• pp.240-249
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• 2007

The objective of this study was to investigate the relation of serum calcium level, body mass index(BMI) with bone status expressed as broadband ultrasound attenuation(BUA) measured by quantitative ultrasound (QUS) and the occurrence of osteopenia among adult men and women. Two hundred eleven(63 male and 148 female) workers who worked in 4 different battery factories were recruited from March 2005 to October 2005. BUA was used as a surrogate of bone mineral density and measured at left calcaneous bone area. The BUA value transformed into T-score by WHO standard conversion criteria to determine osteopenia (-2.5