• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.6
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• pp.1057-1062
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• 2016

In this paper, a design method for a compact log-perio dic half-bow-tie dipole array antenna for an operation in a UWB band(3.1-10.6 GHz) is studied. The proposed antenna is miniaturized by using half-bow-tie shaped dipole elements instead of strip-type dipole elements, which are commonly used in a general log-periodic dipole array(LPDA) antenna, and by reducing the element spacing. The effects of the flare angle of the half-bow-tie elements and the spacing factor on input reflection coefficient and realized gain characteristics of the proposed log-periodic antenna are analyzed. The optimized antenna is fabricated on an FR4 substrate, and the experiment results show that the antenna has a frequency band of 2.95-11.31 GHz for a VSWR < 2, which assures the operation in the UWB band. In addition, the length and width of the proposed antenna are reduced to 32.1 % and 18.3 %, respectively, compared to the LPDA antenna.

• Journal of Applied Biological Chemistry
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• v.59 no.3
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• pp.215-220
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• 2016

Abstract Secondary cell wall is the most abundant biomass produced by plants. Plant secondary cell wall is composed of a complex mixture of cellulose, hemicellulose, and lignin. Lignin, a phenolic polymer that hinders the degradation of cell wall polysaccharides to simple sugars destined for fermentation to bio-ethanol. Cell wall biosynthesis pathway-specific biomass engineering offers an attractive 'genetic pretreatment' strategy to improve bioenergy feedstock. Recently, we found a transcription factor, MYB7, which is a transcriptional switch that may turns off the genes necessary for lignin biosynthesis. To gain insights into MYB7 mediated transcriptional regulation, we first established a dominant suppression system in Arabidopsis by expressing MYB7-SRDX. Then we used a transient transcriptional activation assay to confirm that MYB7 suppress the transcription of the lignin biosynthetic gene. Taken together, we conclude that MYB7 function as a repressor of the genes involved in the lignin biosynthesis.

• Journal of Distribution Science
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• v.17 no.10
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• pp.107-114
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• 2019

Purpose - This is longitudinal research which aims to investigate the meaning of greenness to consumers' behavior. Consumers adopt green marketing as a new factor in product buying and consumption and more and more consumers prefer green product and services. Consumers' green buying behavior can be different from other purchasing experiences. There would be changes in the meaning of green as time passed and it can be different from countries to other countries. This study examines focus group studies with several groups. There is a ten-year gap between 2010 focus group and 2019 focus group interviews. With this ten-year gap, we can find the change of greenness to consumers. Research design, data, and methodology - The data were collected from Turkish, Korean, Kazakhstan people. This is a cross-sectional study and focus group interview was designed. We can gain information relevant to the research problem with using focus group study and get some insights into basic needs and attitudes of green marketing. The subjects for green purchase interviewee were confined to under 40 years old's shoppers regardless of gender. The first study was investigated with several groups in 2010 and the second interview were conducted in 2019. Results - Results show that the meaning of greenness for consumer has changed over time in accordance with the growing accordance of environmental sustainability. Basically, green marketing still means valuable, natural, recycle-able, good for health, clean, smart behavior, essential benefit. The concept of greenness significantly evolved since it was investigated in 2010. It moves away from focusing on specific environmental issues to considering global sustainability issues. Especially we found that greenness can be related with globalization, higher education, social status at the 2019 interview. Conclusions - This paper attempted to confirm the green marketing is essential and expands its meaning to various aspect. Usually, we can think green marketing is everywhere, therefore, people don't care about green issues in real. But consumers are adopting green marketing more and more, it can be a means to attract potential consumers. Therefore, companies should provide enough greenness information for people and they might apply greenness communication to attract potential customers.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.3
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• pp.283-291
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• 2015

In this paper, a negative impedance converter, the key element of non-Foster matching to enhance the bandwidth of matching high Q-factor passive element, is presented. Proposed negative impedance converter is implemented by the topology of Linvill's transistor negative impedance converter circuit. It is hard to forecast the operation of negative impedance circuit, because it is composed of gain element and positive feedback. Therefore the negative impedance circuit is implemented by hybrid type beforehand to check out the feasibility and it is designed by integrated circuit. The integrated circuit is fabricated by commercial $0.18{\mu}m$ SiGe BiCMOS process, and non-Foster matching is observed at 700~960 MHz band by cancelling the target reactance.

• Journal of Environmental Health Sciences
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• v.46 no.1
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• pp.96-102
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• 2020

Objectives: This study identified factors impacting radiation knowledge among aircrew, who are affected by cosmic radiation exposure due to their occupational environment. Methods: In September 2019 we conducted an online survey of aircrew through a Google link. We evaluated the level of radiation knowledge using a ten-item (10 points) questionnaire. The following exploratory variables were evaluated in relationship with the level of radiation knowledge using univariable linear regression models: sex, age, duration of employment, position level, company, marriage, education level, personal/family history of disease, and the number of times acquiring information on radiation through various channels (internet searching, watching television, reading newspaper, conversation about radiation with aircrew/non-aircrew, in-house training). With a p of 0.2 in univariable models, we built a multivariable linear regression model using a stepwise selection method. Results: The average radiation knowledge score of the 356 respondents was 7.22. Univariable linear regression analysis showed that radiation knowledge of the aircrew was associated with their company, position level, age, and number of conversations with other aircrew members. Our multivariable model showed that the radiation knowledge level of aircrew decreased as they had more conversations about radiation with other aircrew members and as their age increased. Conclusions: Korean air crew showed a lower level of radiation knowledge as their age and the number of conversations with colleagues increased. The study suggests that more education is needed in order for aircrew to gain accurate radiation knowledge.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.2
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• pp.207-214
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• 2015

The effects of high carbohydrate diet on growth, serum physiological response, and hepatic heat shock protein 70 expression in Wuchang bream were determined at $25^{\circ}C$ and $30^{\circ}C$. At each temperature, the fish fed the control diet (31% CHO) had significantly higher weight gain, specific growth rate, protein efficiency ratio and hepatic glucose-6-phosphatase activities, lower feed conversion ratio and hepatosomatic index (HSI), whole crude lipid, serum glucose, hepatic glucokinase (GK) activity than those fed the high-carbohydrate diet (47% CHO) (p<0.05). The fish reared at $25^{\circ}C$ had significantly higher whole body crude protein and ash, serum cholesterol and triglyceride, hepatic G-6-Pase activity, lower glycogen content and relative levels of hepatic growth hormone (GH) gene expression than those reared at $30^{\circ}C$ (p<0.05). Significant interaction between temperature and diet was found for HSI, condition factor, hepatic GK activity and the relative levels of hepatic GH gene expression (p<0.05).

• Journal of Families and Better Life
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• v.23 no.5 s.77
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• pp.133-143
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• 2005

The purpose of this study was to gain understanding about residential satisfaction and preference of the members of the future elderly generation who have an intention to develop senior congregate housing. The data for this study were collected from 600 participants who were in their 40s to 60s, residing in Seoul, and who have an intention to develop senior congregate housing. The data collection spanned from December 1st to 20th, 2004. The results of this study were as follows: Firstly, the respondents who had a higher level of education, higher income, and a high-ranking job showed relatively higher residential satisfaction with their present house. Similar satisfaction level came between their present house and expecting ones in their later life. Financial responsibility was the most serious expected problem when they continue living in the present house in the later life. It means that the economic ability is the primary factor that determines whether they will have a stable life later. Secondly, as for the preference for the senior housing developer type, the group who preferred collectively developed senior congregate housing far outnumbered the other who preferred independent developer type. Also, the group who preferred collective developer type had higher economic ability than that of the other. These results indicate that above all, economic competence is the must significant variable, which should be considered in the future life and residential planning for the elderly. Korean senior congregate housing models should be developed based upon elaborate research. It is also necessary to develop different types of housing, such as a more practical type and a high quality type, as well as to respond to different kinds of developmental objectives, such as marketability and public benefit.

• Preventive Nutrition and Food Science
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• v.8 no.3
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• pp.253-259
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• 2003

Conjugated linoleic acid (CLA) is a class of positional, geometric conjugated dienoic isomers of linoleic acid (LA). CLA activates the immune system, protects against tumorigenesis, and reduces the incidence of atherosclerosis. Trans-10, cis-12 CLA has specific effects on lipid metabolism, it has been shown to reduce body fat gain and regulates some adipocyte secreted proteins in vivo and in vitro. Here we report that a CLA mixture affects cytokine secretion from rat primary adipocytes. Rat primary adipocytes were treated with 1 mM, 100 $\mu$M, 1 $\mu$M or 100 nM CLA mixture doses; and leptin, tumor necrosis factor alpha (TNF a ), interleukin-6 (IL-6) and glycerol levels in the medium were measured. Leptin secretion was lower, TNF $\alpha$ secretion higher and IL-6 secretion did not change in response to the CLA mixture. Leptin and TNF $\alpha$ secretions did not change with CLA mixture treatment in a dose-dependent manner. In addition, the CLA mixture did not appear to enhance lipolysis in rat primary adipocytes. In conclusion, our study demonstrates that the decrease in leptin and increase in TNF $\alpha$ secretion in adipocytes treated with CLA mixture may be due to the apoptotic effect and to a reduction in peroxisome proliferator-activated receptor gamma (PPAR ${\gamma}$ ) ligands.

• Journal of Korean Society for Quality Management
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• v.42 no.2
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• pp.253-264
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• 2014

Purpose: The aim of this study is to gain a competitive advantage in the global marketplace by examining the current situation of three domestic Food Dehydrator companies' products. Food Dehydrators are sort of small domestic appliances(SDA), first introduced by Korean companies. Furthermore, this study suggests the improvement plans in the rapidly changing world situation. Methods: Evaluate through comparing three domestic Food Dehydrator companies' products based on the PQI(Premium Quality Index) model, developed by product quality evaluation experts group. Results: At first, we classified evaluation factors into three parts - usability quality, emotional quality - and each of the factors includes sub factors. Under this condition, the results of this study are as follows; the brand quality is remaining at a high satisfaction level compare to other two factors but emotional quality is assessed to be low. This study has shown at customers consider brand and usability quality factors as the most important factor due to the nature of the product. Conclusion: As the possibility of increasing customer needs such as product design and sensitive quality besides usability quality has risen in a competitive global market, the manufacturing companies in Korea are recommended to put forth the necessary effort to improve their product quality, especially in terms of emotional quality.

• Mycobiology
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• v.45 no.2
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• pp.90-96
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• 2017

Different endophytes isolated from the seeds of Sophora flavescens were tested for their ability to produce matrine production. Response surface methodology (RSM) was applied to optimize the medium components for the endophytic fungus. Results indicated that endophyte Aspergillus terreus had the ability to produce matrine. The single factor tests demonstrated that potato starch was the best carbon source and the combination of peptone and $NH_4NO_3$ was the optimal nitrogen source for A. terreus. The model of RSM predicted to gain the maximal matrine production at $20.67{\mu}g/L$, when the potato starch was 160.68 g/L, peptone was 24.96 g/L and $NH_4NO_3$ was 2.11 g/L. When cultured in the optimal medium, the matrine yield was an average of $20.63{\pm}0.11{\mu}g/L$, which was consistent with the model prediction. This study offered an alternative source for the matrine production by endophytic fungus fermentation and may have far-reaching prospect and value.