• Journal of the Korean Vacuum Society
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• v.14 no.4
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• pp.207-214
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• 2005

This paper presents a channel structure for promising high performance pseudomorphic high electron mobility transistor(pHEMT) switching device for design and fabricating of microwave control circuits, such as switches, phase shifters, attenuators, limiters, for application in personal mobile communication systems. Using the designed epitaxial channel layer structure and ETRI's $0.5\mu$m pHEMT switch process, single pole double throw (SPDT) Tx/Rx monolithic microwave integrated circuit (MMIC) switch was fabricated for 2.4 GHz and 5 GHz band wireless local area network (WLAN) systems. The SPDT switch exhibits a low insertion loss of 0.849 dB, high isolation of 32.638 dB, return loss of 11.006 dB, power transfer capability of 25dBm, and 3rd order intercept point of 42dBm at frequency of 5.8GHz and control voltage of 0/-3V These performances are enough for an application to 5 GHz band WLAN systems.

• Current Research on Agriculture and Life Sciences
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• v.32 no.3
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• pp.111-117
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• 2014

Phytophthora blight caused by Phytophthora capsici Leonian is a dangerous disease threatening pepper growers worldwide. The efficacy of chemical control is generally low as the pathogen is soil-borne and rapidly spread by zoospores during the rainy season. Thus, based on the demand for resistant varieties, various good resistant sources, such as CM334, AC2258, and PI201234, have been reported and their inheritance of resistance studied by many different authorities. However, the mode of inheritance remains unclear, as 1 or 2 independent dominant genes, 3 genes, or multiple genes have all been reported as responsible for resistance. Recently, QTL mappings of the gene factors for resistance have been reported, and molecular markers for resistance used in breeding programs. With the release of many resistant commercial hybrid cultivars, differentiation of pathotypes of the pathogen is attracting interest among breeders and plant pathologists. Various authorities have already classified the pathogen strains into different races according to the inter-action between resistant host plants, including the source of resistance, such as CM334 and PI201234, and resistant commercial varieties and P. capsici isolates. However, no standard differential host sets have yet been established, so the results are good only for the pathogen strains used in the experiments. Thus, for breeding varieties with durable resist-ance, it is important to introduce resistance from different sources and use diverse local pathogen strains collected in the target area for distribution in a breeding program.

• Allergy, Asthma & Immunology Research
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• v.10 no.6
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• pp.698-715
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• 2018

Purpose: Hrd1 has recently emerged as a critical regulator of B-cells in autoimmune diseases. However, its role in the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP) remains largely unexplored. This study aimed to examine Hrd1 expression and B-cell accumulation and their possible roles in CRSwNP. Methods: Quantitative real-time polymerase chain reaction, immunohistochemistry, enzyme-linked immunosorbent assay and Western blotting were used to assess gene and protein expression in nasal tissue extracts. Cells isolated from nasal tissues and peripheral blood mononuclear cells were characterized by flow cytometry. Local antibody production was measured in tissue extracts with a Bio-Plex assay. Additionally, changes in Hrd1 expression in response to specific inflammatory stimuli were measured in cultured dispersed polyp cells. Results: Nasal polyps (NPs) from patients with eosinophilic CRSwNP (ECRS) had increased levels of Hrd1, B-cells and plasma cells compared with NPs from patients with non-eosinophilic CRSwNP (non-ECRS) or other control subjects (P < 0.05). The average Hrd1 levels in B-cells in NPs from ECRS patients were significantly higher than those from non-ECRS patients and control subjects (P < 0.05). NPs also contained significantly increased levels of several antibody isotypes compared with normal controls (P < 0.05). Interestingly, Hrd1 expression in cultured polyp cells from ECRS patients, but not non-ECRS patients, was significantly increased by interleukin-$1{\beta}$, lipopolysaccharide and Poly(I:C) stimulation, and inhibited by dexamethasone treatment (P < 0.05). Conclusions: Differential Hrd1 expression and B-cell accumulation between the ECRS and non-ECRS subsets suggests that they can exhibit distinct pathogenic mechanisms and play important roles in NP.

• Journal of Korean Society on Water Environment
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• v.37 no.1
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• pp.32-46
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• 2021

South Korea has been divided into quantities and water quality, and due to a revision of the Government Organization law in June 2018, the controversial water management system was integrated into the Ministry of Environment. The total Maximum Daily Loads System has been called the flower of water quality control, and since 2004, all three major river systems which have been introduced into the Han River system, despite its various difficult environments, and subsequently leading to all of the four major rivers undergoing obligatory implementation since 2013. Currently, the target TMDL (Han River Phase 1 and Other Water Systems Phase 3) for the 2020 stage has been implemented. The domestic TMDL established a basic plan for calculating the load which complies with the unit watershed's target water quality, as well as an implementation plan for annual load management, both which have been institutionalized in order to evaluate load compliance on a repeated annual basis. Local governments ask external organizations to conduct investigations every year in order to assess the transition, which thereby requires tens of millions of won every year. Therefore, an assessment and management model that can be easily operated at the TMDL personnel level is required. In this study, when the Han river Water System TMDL was implemented in earnest, we confirmed the the water quality improvement effect when TMDL was introduced to major inflow tributaries (TancheonA, JungnangA, AnyangA) under the Seoul City's jurisdiction through the use of the total amount control unit basin evaluation technique. By presenting customized management measures, we propose the guidelines that are necessary for determining more effective water environmental policies.

• Journal of agricultural medicine and community health
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• v.46 no.4
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• pp.253-265
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• 2021

Objectives: The aim of the study is to identify the success factors of 6 months of smoking cessation targeting male workers in small and medium-sized businesses. Methods: The subjects of this study were smoking male workers who had got the visiting services at a tobacco control center to stop smoking from January 2018 to December 2020. Total number of the participants was 767. Results: The male workers in small and medium enterprises had a success rate of 20.2% for smoking cessation for 6 months. With multiple logistic regression, the factors causing the differences in the success rate for 6 months of the workers were as follows. - The odds ratios (ORs)(95% confidence interval, CI) of the age group of under 29 and 40-49 years were 0.10 (0.03-0.29) and 0.43 (0.24-0.76), respectively, compared to the 50 years and older group. The ORs (95% CI) of the daily average of smoking group of 11-20 and more than 21 were 0.52(0.34-0.80) and 0.46(0.24-0.90), respectively, when compared to the group of 1-10. The ORs (95% CI) of the supporting persons for quitting smoking group of with spouse and other family were 1.99(1.18-3.34), compared to the group with no one. Conclusions: This study showed that the chance of success for smoking cessation for 6 months is higher when the subjects have spouses and other family Supporting persons for quitting smoking. And it also shows that the less they smoke a day and the older they are, the more likely it is to succeed in quitting smoking.

• Mood & Emotion
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• v.16 no.3
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• pp.158-162
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• 2018

Objectives : The purpose of this study was to examine psychosocial factors related to burnout of social welfare officers working in Jeonnam Province. Methods : A total of 395 social welfare officers (male 99, female 296) working in 22 areas of Jeollanam-do province, were subjects of this study. We examined socio-demographic factors, using a self-reporting questionnaire. Subjects were asked to complete the Maslach Burnout Inventory-General Survey (MBI-GS), Center for Epidemiological Studies Depression Scale (CES-D), Perceived Stress Scale (PSS), and the Generalized Self-Efficacy Scale (GSS), to assess psychosocial factors affecting to burnout of social welfare officers. Results : Among 395 subjects, 221 (55.9%) reported recent experiences of burnout. There was no significant difference in age between two groups, divided by burnout. Sex (p<0.001), rank (p=0.003), working period (p=0.034), depression (p<0.001) revealed differences between the burnout group and control group. Scores of PSS (p<0.001) were higher, while the scores of GSS (p<0.001) were lower in the burnout group, than control group. Multivariate logistic regression analysis revealed that female (OR 2.840, 95%CI 1.466-5.504, p=0.002), depressive high-risk group (OR 6.824, 95%CI 2.893-16.096, p<0.001) PSS (OR 1.247, 95%CI 1.153-1.349, p<0.001) and GSS (OR 0.950, 95%CI 0.930-0.971, p<0.001), were significantly associated with burnout. Conclusion : We found that some factors, were associated with experienced burnout in social welfare officers. Depressive symptoms were the strongest associative factor, for burnout in public servants in charge of social welfare. Sex, stress and self-efficacy also correlated with burnout, and especially self-efficacy was a protecting factor.

• The Korean Journal of Archival Studies
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• no.7
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• pp.37-74
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• 2003

An Old document(Diploma) is a historical and unique record, so it must be collected, arranged, and preserved for research as soon as possible. Especially, for the effective use of the Old Document(Diploma), it is needed to arrange and describe the material systematically on the ground of modern archival theory. The Kyujanggak Archives in the Seoul National University has published 23 volumes of Old document(Diploma) material Old Document(Diploma). But they seem to cause the readers inconvenience, because the materials are classified and gathered only by genre, the titles or the orders of the materials are not standardized, and there is no description about the content of each Old document(Diploma). Jangseo-gak Library in The Academy of Korean Studies has also published the series of Old document(Diploma) material Old Document(Diploma) Collection. However the case is not different, since they are all mixed up with materials classified and gathered by genre, family, academy, or local school. And a great part of the materials have no titles and no description about the content of each Old document(Diploma), either. About the arrangement and description of the records, European and American archival science has established the theory of l)the principle of provenance, 2)the principle of original order, 3)levels of control, 4)collective description. These theories are valuable for the effective use of Old document(Diploma). On the viewpoint of the principle of provenance, Old document(Diploma) materials should not be classified by subject and genre, but by family and person. Then, the Old document(Diploma) materials, after collected by the unit of family or person on the viewpoint of the principle of provenance, should be arranged in their original order for more detailed arrangement and furthermore, for the work to find their relationship. This is so called the principle of original order. The hierarchical management of the Old document(Diploma) materials, for example, classifying by record group, sub-group, series, item and so on, is the concept of the levels of control, and comprehensive description of the each hierarchical structure is the concept of the collective description. Let's apply these archival theories to 34 pieces of the Chung, Man-Seok's material in the series of Old document(Diploma) material Old Document(Diploma). First, collect the Old document(Diploma) materials into Chung, Man-Seok's collection(the principle of provenance), which were scattered in the series classified by genre. Secondly, rearrange them chronologically(the principle of original order), and then we can find the comprehensive information about Chung, Man-Seok. For the hierarchical management of the Old document(Diploma) materials, we should establish a few concepts from the general, large group to specific, small item. The concepts can be organized as following; l)record group(Chung, Man-Seok record group) - 2)sub-group(personnel document, property document, family document, social activity document, political activity document, etc) - 3)series(gyoji-series, gyoseo-series, yuji-series etc. in the personnel document) - 4)folder(document with additions) - 5)item(one document). According to the the theory of the collective description, in the level of record group, there should be a collective description of Chung, Man-Seok's biography or a summary of record group. Similarly, there should be a collective description of a summary of sub-group in the level of sub-group and a summary of series in the level of series.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.1
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• pp.17-32
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• 2019

Sales representatives of automobile company play a key role in the circulation system. Given the characteristics of the good, consumers demand high-quality information and guides from the salespersons when they decide to purchase an automobile. Sales representatives provide service to the customers in accordance with their needs to help purchase decision-making process. Therefore, a sales representative's personal competence have a significant effect on sales performance. Based on this hypothesis, we assumed that personal competence of a salesperson has a positive correlation with sales performance. An empirical analysis was conducted to test the hypothesis. This study classifies personal competence into 4 independent variables((1) sales technique professionalism (2) salesperson's attitude and relationship with customers (3) emotion utilization (4) emotion control) and measures the correlation with the dependent variable(sales performance). To verify the relationship, we set and modified the hypothesis based on the precedent studies and researches. In addiction, a survey was conducted targeting 300 local salespersons from Gyeonggi-Gangwon region. 268 valid samples were used and analyzed with SPSS WIN24.0 statistical program. As a result of an empirical analysis, it turned out that sales technique professionalism and emotion utilization have positive correlation with sales performance. However, the result failed to support the assumption that sales representative's attitude and relationship with customers and emotion control have positive correlation with sales performance. At last the result revealed that personal competence should be considered as an important determinant of recruitment specification for sales representatives.

• Korean Journal of Environmental Biology
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• v.36 no.4
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• pp.498-506
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• 2018

The purpose of this study is to examine the restorative effect of Semisulcospira libertina extract, on damaged liver cells induced by D-galactosamine in rats. Treatment of damaged liver cells with S. libertina extract significantly reduced local fatty degeneration, and inflammatory cell necrosis, to levels similar with the undamaged control group. In addition, S. libertina extracts were found to reduce plasma levels of liver damage indicator enzymes, such as AST, ALT, LDH and ALP, to control levels. It also reduced lipid peroxides, and lipid contents within damaged liver tissues. This suggests that S. libertina extract has a restorative effect on liver cells, thus reducing release of damage-associated liver enzymes, and oxidative degradation of lipids. Also, S. libertina extracts were found to be involved in recovery of damaged cells from inflammatory response by suppressing expression of $TNF-{\alpha}$, which leads to tissue injury and necrosis, whereas inducing expression of HO-1 that protects cells during inflammation. Thus, S. libertina extract restores liver tissue from necrosis and fibrosis, as well modulates expression of inflammation-related genes against liver damage. Our findings suggest that S. libertina extract is an effective medicinal resource, for improving and recovering liver cells from hepatic injury.

• Journal of agricultural medicine and community health
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• v.44 no.3
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• pp.115-123
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• 2019

Objective: This study was conducted to examine the effects of a health promotion program on the health condition of rural elderly women implemented at primary health care posts using Korean Frailty Index. Methods: The research was designed a nonequivalent control group pretest-posttest setting. The participants in this study were 50 residents (intervention group: 25, control group: 25) selected from 4 villages 2 primary health care posts in J city Gyeongsangnam-do. The health promotion program was conducted at the primary health care posts twice a week for 12 weeks. This program consisted of basic exercises(Gukseondo + Theraband muscle strength training) and additional activities(including modified Theraband activity, rubber ball exercise, ball massage, nutrition class, singing class). Collected data were analyzed by descriptive statistics, paired t-test, and repeated measures ANOVA with SPSS 21.0. Results: Results of the health promotion program showed that the health conditions(measured by perceived health status, frailty score, upper/lower flexibility, maximum grip strength, dynamic balance test Timed Up and Go) of the experimental group(25) all statistical significantly improved. Conclusion: Study findings indicate that the health promotion program implemented at primary health care posts on rural elderly women is effective and can contribute to a developed health promotion program for local residents in the future.