• Journal of Biomedical Engineering Research
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• v.37 no.2
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• pp.90-103
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• 2016

This research was aimed to analyze load sharing ratios between cortical shell and trabecular bone of a degraded lumbar vertebra with aging, and also evaluate elastic moduli assigned into an FE model, using finite element method. For the better analysis of trabecular bone, effective elastic moduli, that is, nominal elastic moduli divided by the volumetric porosities was used. The elastic moduli of the cortical shell suitable for the trabecular bone were obtained from the equations on the basis of idealized stress-strain relations, including areal porosities. To minimize numerical errors, p-element was used. Using eight parameters that refer to some published papers, the geometry of L3 with a removed posterior part. After the constant compressive displacement was applied, the load sharing ratios were obtained by using both every elastic strain energy and every vertical force between two bones in each 8-volume. As results, 1) according to an increase in age from 20-year to 80-year, load sharing ratios of trabecular bone decreased from 55% to 49%; 2) the maximal ratios of each bone were occurred in the mid-plane of centrums and the endplate of cortical shells, respectively; 3) effective elastic moduli assigned into a porous centrum/cortex were found to be adequate; 4) for load sharing ratios, the difference of two methods showed that the total ratios were almost same within less than 1% but the partial ratios at every depth were more or less different each other.

• Journal of Life Science
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• v.20 no.2
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• pp.208-212
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• 2010

The low and high temperature stress might affect the yield and quality of many crop species. Alternative oxidase (AOX) gene is known as factors related to stress resistance in plants. In order to develop molecular markers related to stress resistance in Chinese cabbage, fifteen ESTs sharing sequence similarity to arabidopsis AOX genes were found using Brassica rapa EST database from NCBI. The polymorphic DNA sequences using the ESTs were then screened between Chinese cabbage, 'Chiifu' and 'Kenshin'. We found four ESTs that have either insertion or deletion between the two cultivars. These polymorphic sites were then targeted for development of the four PCR based molecular markers. These molecular markers developed in this study could be useful for a test of their relationship with abiotic stress resistance in Chinese cabbage.

• Journal of Biomedical Engineering Research
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• v.34 no.1
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• pp.14-23
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• 2013

In this study, biomechanical stability of the newly developed revision total knee arthroplasty (rTKA) was evaluated through strain and stress distribution analysis within the implanted proximal tibia using a three-dimensional finite element (FE) analysis. 2000N of compressive load (about 3 times body weight) was applied to the condyle surface on spacer, sharing by the medial (60%) and lateral (40%) condyles simulating a stance phase before toe-off. The results showed that PVMS within the revision total knee arthroplasty and the proximal tibia were less than yield strength considering safe factor 4.0 (rTKA: less than 10%, Cortical bone: less than 70%, Cancellous bone: less than 70%). The materials composed of them and the strain and stress distributions within the proximal tibia were generally well matched with those of a traditional revision total knee arthoplasty (Scorpio TS revision system, Stryker Corp., Michigan, USA) without the critical damage strain and stress, which may reduce the capacity for bone remodeling, leading to bone degeneration. This study may be useful to design parameter improvement of the revision total knee arthoplasty in biomechanical stability point of view beyond structural stability of revision total knee arthoplasty itself.

• Journal of People, Plants, and Environment
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• v.22 no.3
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• pp.269-277
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• 2019

This study aims to see what changes flower arrangement programs bring to the stress index of elderly people with chronic diseases and its correlation with cognition. Furthermore, seniors from a day care center and a nursing home were compared for the purpose of identifying the effectiveness of flower arrangement activities as a supplementary remedy designed to relieve the symptoms and improve the quality of life of patients with chronic diseases. In this study, 24 seniors with chronic diseases were divided into two groups: Group A consists of 15 seniors from a day care center and Group B consists of nine seniors from a nursing home. Both groups participated in simple flower arrangement activities in 10 sessions. In each session, red and green cut flowers that were preferred by the elderly were provided to elicit and develop their thoughts and behaviors. The results showed that the overall average stress index was significantly reduced from 58.0±11.6 before the program to 50.6±17.1 after the program (p = .037). This study examined that the program was more effective for Group A (p = .021) than for Group B (p = .678). Results of the correlation analysis showed that there was no correlation between cognitive function and stress index (p = .569), but that the activity was more effective for Group A. This study shows that arranging flowers effectively lowers the stress index of elderly people with chronic diseases. Also, sharing the outcomes of such activities with others or continuously caring for the flowers even after the activity can maximize the effectiveness of the therapy and rehabilitation. Thus, the study concluded that the program needs to be applied continuously, not in the short-term, in order to relieve or treat the symptoms of elderly patients with chronic diseases.

• The Journal of Industrial Distribution & Business
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• v.11 no.6
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• pp.29-39
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• 2020

Purpose: The purpose of this study is, in the situation where rapid response to the rapidly changing environment is required due to the development of the fourth industrial revolution such as artificial intelligence, virtual reality, and the internet of things, robotics, big data, additive manufacturing, bio-health, sharing economy and in the organizational culture aspiring toward the innovation of a major company, small business and a public institution, to analyze what influence a job-engagement and stress make, and what influence individual's self-efficacy as a moderator mediator makes, and to offer basic data for improving job-engagement and lowering job-stress. Research design, data, and methodology: For doing this, the literature and the empirical studies were combined. Deriving innovation-oriented organizational culture as factors affecting the job engagement and job stress through the literature, and have established hypotheses to verify them. We have collected data of 281 from ex,ecutives and staff-members working in areas including major company, small business and officials (the central government, a local public service, the prosecution, the police, and school). And these data were analyzed by SPSS 23 version. Results: Based on these data, the results of analysis were as follows; First, the innovation-oriented organizational culture which was recognized by organizational members had effect on job-stress. Second, the innovation-oriented organizational culture which was recognized by organizational members influenced job-stress. Third, in the relationship between the innovation-oriented organizational culture and job-engagement, self-efficacy did not influenced job-engagement. Finally, in the relationship between the innovation-oriented organizational culture and job-stress, self-efficacy influenced job-stress. Conclusions: Innovation-oriented organizational culture places importance on the organization's adaptability and flexibility in the external environment, so companies need to establish an innovation-oriented organizational culture favorable to achieving survival and successful innovation, and to develop and disseminate programs of positive and continuous organizations to improve task enthusiasm, reduce task stress, and enhance organizational performance. In the future, it will be necessary to verify the effectiveness of various organizational culture types through comparative analysis with companies that actively maintain an innovation-oriented organizational culture (Google, Kakao, etc.) and companies that prefer hierarchy-oriented organizational culture, relationship-oriented organizational culture, and market-oriented organizational culture.

• Korean Journal of Human Ecology
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• v.12 no.4
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• pp.433-447
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• 2003

Since self-efficacy was suggested by Bandura(1977) as the most important factor that affects human behavior, preceding studies about self-efficacy are frequently related with children, and it is a main stream that only personal factors are chosen as related factors of these studies. Considering we don't have enough studies about family factors that reflect qualitative and relational factors of adolescents' home background, this study was aimed to seize the actual condition of self-efficacy meaning perceived and emotional faith about their own ability. These are our major concerns: 1. What kind of tendency does self-efficacy and appearance stress of adolescents, family functioning show? 2. How strong are relative influences of variables on self-efficacy of adolescents? This study was operated on July and August, 2002, aimed 378 middle school and high school students in Jeon-Nam, Mokpo area. 378 question sheets were used for analysis. Followings are results of this study. First, aimed students' average mark of self-efficacy was 2.09, which meant a normal level. And in low-ranked part, self-control-efficacy was the highest, and confidence task difficulty preference was following. Furthermore, whole self-efficacy showed a little difference from the demographic factor of adolescents. In low-ranked part, however, confidence and self-efficacy showed a somewhat difference. As students grew up, confidence decreased, and male students showed higher self-control-efficacy than female ones. Second, appearance stress and family functioning degree had a strong relation with self-efficacy. Family functioning, had important interrelation not only with whole self-efficacy but also with low-ranked part of self-efficacy. In low-ranked part, self-control-efficacy and task difficulty preference were proportional to the family functioning degree. From these results, we can find that the appearance stress was an actual factor that affected the self-efficacy of adolescents, and their self-efficacy was strongly related with family functioning degree. Accordingly, affirmative emotion in family, harmonic communication among family members and sharing housekeeping works had an immediate influence on elevation of self-efficacy.

• Journal of Pharmacopuncture
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• v.20 no.1
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• pp.5-9
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• 2017

Objectives: Gan Mai Da Zao (GMDZ) decoction is widely used for the treatment of various diseases of the internal organ and of the central nervous system. The aim of this study is to investigate the effects of GMDZ decoction on neuropsychiatric disorders in an animal model. Methods: We searched seven databases for randomized animal studies published until April 2015: Pubmed, four Korean databases (DBpia, Oriental Medicine Advanced Searching Integrated System, Korean Studies Information Service System, and Research Information Sharing Service), and one Chinese database (China National Knowledge Infrastructure). The randomized animal studies were included if the effects of GMDZ decoction were tested on neuropsychiatric disorders. All articles were read in full and extracted predefined criteria by two independent reviewers. Results: From a total of 258 hits, six randomized controlled animal studies were included. Five studies used a Sprague Dawley rat model for acute psychological stress, post-traumatic stress disorders, and unpredictable mild stress depression whereas one study used a Kunming mouse model for prenatal depression. The results of the studies showed that GMDZ decoction improved the related outcomes. Conclusion: Regardless of the dose and concentration used, GMDZ decoction significantly improved neuropsychiatric disease-related outcomes in animal models. However, additional systematic and extensive studies should be conducted to establish a strong conclusion.

• Journal of the Korean Geotechnical Society
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• v.30 no.4
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• pp.5-19
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• 2014

In this study, the structural analysis is performed on the method of shallow block and deep cement mixing pile, and then their characteristics and associated behaviors were analyzed. In the case of continuous beam analysis, the predicted settlement was very small, and shear force and bending stress are somewhat overestimated. The frame method is similar to numerical analysis in the internal force shallow block and long pile, but because the settlement of pile is underestimated, the additional calculation using the reaction of the long pile is necessary. For soil arching method and piled raft foundation method, the excessive axial force of long pile was predicted because the load sharing of pile is very large compared to the other methods. In the behavior of the shallow block and deep pile method, the settlement of shallow block and contact pressure are much in the center than the edge. In the estimating method considering the interaction between improved material and ground, the load sharing of the soil-cement pile ranges from 20% to 45%, and the stress ratio is 2.0~5.0 less than piled DCM. The maximum member forces at the boundary conditions of pile head are similar, but in fixed head the axial force and vertical displacement are different in accordance with pile arrangement.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.22 no.1
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• pp.11-18
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• 2018

Objectives The incidence of degenerative diseases is increasing as society ages, and this increased the economic burden on society. Oxidative stress was also under suspicion as one of the causes. Recent studies have found that Curcuma longa Rhizoma had antioxidant, anti-inflammatory, antimutagenic, and anticancer effects. Through this study, we figure out trends in Curcuma longa Rhizoma research and evaluate the therapeutic potential of Curcuma longa Rhizoma for dementia. Methods The search was made using domestic and international internet search sites. "Naver academic," "Google scholar," "Korea institute of oriental medicine (KIOM OASIS)," "Korean traditional knowledge portal (KTKP)," "Library of Congress," "Research information sharing service (RISS)," "National Digital Science Links (NDSL)," and "Pub med" are used to search. The searched for words were "turmeric," "Curcuma longa Rhizoma," "antioxidant," and "nerve regeneration." Results It could be seen that a lot of research done on Curcuma longa recently. In previous studies, the most common research disease was cancer. In previous studies, the most common effects of Curcuma longa was antioxidant and anticancer. Curcumin, Vitamin B1, and various essential oils were the functional components of Curcuma longa Rhizoma. Curcuma longa Rhizoma performs DPPH radical scavenging activity and ABTS radical cation decolorization activity; it inhibits NO and iNOS. Conclusion The destruction of nerve cells due to oxidative stress is a cause of dementia. Curcuma longa Rhizoma have antioxidant effects. Therefore, we believed that it is an effective treatment for dementia. Various studies will be made on Curcuma longa Rhizoma.

• Journal of Power Electronics
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• v.13 no.1
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• pp.20-30
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• 2013

This paper presents a soft switching DC/DC converter for high voltage application. The interleaved pulse-width modulation (PWM) scheme is used to reduce the ripple current at the output capacitor and the size of output inductors. Two converter cells are connected in series at the high voltage side to reduce the voltage stresses of the active switches. Thus, the voltage stress of each switch is clamped at one half of the input voltage. On the other hand, the output sides of two converter cells are connected in parallel to achieve the load current sharing and reduce the current stress of output inductors. In each converter cell, a half-bridge converter with the asymmetrical PWM scheme is adopted to control power switches and to regulate the output voltage at a desired voltage level. Based on the resonant behavior by the output capacitance of power switches and the transformer leakage inductance, active switches can be turned on at zero voltage switching (ZVS) during the transition interval. Thus, the switching losses of power MOSFETs are reduced. The current doubler rectifier is used at the secondary side to partially cancel ripple current. Therefore, the root-mean-square (rms) current at output capacitor is reduced. The proposed converter can be applied for high input voltage applications such as a three-phase 380V utility system. Finally, experiments based on a laboratory prototype with 960W (24V/40A) rated power are provided to demonstrate the performance of proposed converter.