• Journal of Drive and Control
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• v.16 no.4
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• pp.16-22
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• 2019

The electro-hydraulic training device (TP511) provided by Festo Didactic are widely used, but teaching materials do not include mathematical modeling. Thus, there is a limit for full-scale learning about the electro-hydraulic servo system by using this equipment. In this study, for the purpose of improving students' understanding of the classical control and modern control Festo's electro-hydraulic servo training device (TP511) was mathematically modeled and parameter values were calculated by examining the characteristics of each component. And P, PI, PD, and PID controllers highly used in the industrial field, were designed by using the root locus method to achieve the optimal gains and used for simulation and experiments using the Festo's electro-hydraulic servo training apparatus. The validity of the derived mathematical model and the calculated parameter values were verified through simulation and experiment. It was found that the p control can achieve the control target more effectively than the pid control for Festo's electro-hydraulic servo training system by using the root locus method.

• Korean Journal of Microbiology
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• v.24 no.3
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• pp.221-227
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• 1986

The strain of Aspergillus nidulans carring a uvsH mutation which had been shown to be absolutely required for UV or 4-NQO induced mutagenic processes was studied on mitotic recombinational behaviour. Although the effect of uvsH locus on spontaneous mitotic crossing over between fpB37 and centromere was not considerable, UV-induced intergenic recombination did not occur in uvsH/uvsH homozygotic diploid. In case of gene conversion at riboflavin locus between a pair of non-complementary alleles, riboA1 and riboA3, the uvsH mutation was not concerned with that process occurred spontaneously or induced by UV irradiation. When the cells were irradiated by UV light, high degrees of aneuploid productions were detected in diploid homozygous for uvsH as compared with wild type, while much difference was not found during normal growth.

• Mycobiology
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• v.46 no.4
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• pp.407-415
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• 2018

Pheromone (PHB)-receptor (RCB) interaction in the mating pheromone response pathway of Lentinula edodes was investigated using synthetic PHBs. Functionality of the C-terminally carboxymethylated synthetic PHBs was demonstrated by concentration-dependent induction of a mating-related gene (znf2) expression and by pseudoclamp formation in a monokaryotic strain S1-11 of L. edodes. Treatment with synthetic PHBs activated the expression of homeodomain genes (HDs) residing in the A mating type locus, and of A-regulated genes, including znf2, clp1, and priA, as well as genes in the B mating type locus, including pheromone (phb) and receptor (rcb) genes. The synthetic PHBs failed to discriminate self from non-self RCBs. PHBs of the B4 mating type (B4 PHBs) were able to activate the mating pheromone response pathway in both monokaryotic S1-11 and S1-13 strains, whose B mating types were B4 (self) and B12 (non-self), respectively. The same was true for B12 PHBs in the B4 (non-self) and B12 (self) mating types. The synthetic PHBs also promoted the mating of two monokaryotic strains carrying B4-common incompatible mating types ($A5B4{\times}A1B4$). However, the dikaryon generated by this process exhibited abnormally high content of hyphal branching and frequent clamp connections and, more importantly, was found to be genetically unstable due to overexpression of mating-related genes such as clp1. Although synthetic PHBs were unable to discriminate self from non-self RCBs, they showed a higher affinity for non-self RCBs, through which the mating pheromone response pathway in non-self cells may be preferentially activated.

• The Plant Pathology Journal
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• v.37 no.2
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• pp.137-151
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• 2021

The present study describes the bacterial blight of walnut, caused by Xanthomonas arboricola pv. juglandis (Xaj) in the northern Gyeongbuk province, Korea. Disease symptoms that appear very similar to anthracnose symptoms were observed in walnut trees in June 2016. Pathogens were isolated from disease infected leaves, fruits, shoots, bud, flower bud of walnut, and cultured onto yeast dextrose carbonate agar plates. Isolated bacteria with bacterial blight symptoms were characterized for their nutrient utilization profiles using Biolog GN2 and Vitek 2. In addition, isolates were subjected to physiological, biochemical, and morphological characterizations. Furthermore, isolates were identified using 16S rDNA sequence analysis, and multi-locus sequence analysis using atpD, dnaK, efp, and rpoD. To confirm pathogenicity, leaves, fruits, and stems of 3-year-old walnut plants were inoculated with bacterial pathogen suspensions as a foliar spray. One week after inoculation, the gray spots on leaves and yellow halos around the spots were developed. Fruits and stems showed browning symptoms. The pathogen Xaj was re-isolated from all symptomatic tissues to fulfill Koch's postulates, while symptoms were not appeared on control plants. On the other hand, the symptoms were very similar to the symptoms of anthracnose caused by Colletotrichum gloeosporioides. When walnut plants were inoculated with combined pathogens of Xaj and C. gloeosporioides, disease symptoms were greater in comparison with when inoculated alone. Xaj population size was more in the month of April than March due to their dormancy in March, and sensitive to antibiotics such as oxytetracycline and streptomycin, while resistant to copper sulfate.

• Journal of Microbiology and Biotechnology
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• v.32 no.12
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• pp.1605-1614
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• 2022

The strains associated with foodborne Salmonella enterica Thompson outbreaks in Korea have not been identified. Therefore, we characterized S. Thompson strains isolated from chocolate cakes linked to foodborne outbreaks in Korea. A total of 56 strains were isolated from preserved cake products, products in the supply chain distribution, the manufacturer's apparatus, and egg white liquid products used for cream preparation. Subsequently, serological typing, pathogenic gene-targeted polymerase chain reaction (PCR), pulsed-field gel electrophoresis (PFGE), and whole-genome multi-locus sequence typing (wgMLST) were performed to characterize these isolates. The antigen formula of all isolates was 7:k:1,5, namely Salmonella enterica subsp. enterica Serovar Thompson. All 56 isolates harbored invA, his, hin, and stn, and were negative for sefA and spvC based on gene-targeted PCR analyses. Based on PFGE results, these isolates were classified into one group based on the same SP6X01.011 pattern with 100% similarity. We selected 19 strains based on the region and sample type, which were subjected to wgMLST. Although the examined strains showed 100% similarity, they were classified into seven clusters based on allelic differences. According to our findings, the cause of these outbreaks was chocolate cake manufactured with egg white liquid contaminated with the same Salmonella Thompson. Additionally, comparative analysis of wgMLST on domestic isolates of S. Thompson from the three outbreaks showed genetic similarities of over 99.6%. Based on the results, the PFGE and wgMLST combination can provide highly resolved phylogeny and reliable evidence during Salmonella outbreak investigations.

• Communications of the Korean Mathematical Society
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• v.23 no.1
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• pp.11-18
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• 2008

For a nef and big divisor D on a smooth projective surface S, the inequality $h^{0}$(S;$O_{s}(D)$) ${\leq}\;D^2\;+\;2$ is well known. For a nef and big canonical divisor KS, there is a better inequality $h^{0}$(S;$O_{s}(K_s)$) ${\leq}\;\frac{1}{2}{K_{s}}^{2}\;+\;2$ which is called the Noether inequality. We investigate an inequality $h^{0}$(S;$O_{s}(D)$) ${\leq}\;\frac{1}{2}D^{2}\;+\;2$ like Clifford theorem in the case of a curve. We show that this inequality holds except some cases. We show the existence of a counter example for this inequality. We prove also the base-locus freeness of the linear system in the exceptional cases.

• Research in Community and Public Health Nursing
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• v.7 no.1
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• pp.52-68
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• 1996

As a product of poverty, health means the physical, mental and social instability caused by poverty. High mortality, high morbidity, and unsatisfied needs for medical care indicate the health condition of poor people. These indicators are related to the social and psychological property. This study is to develop an effective method of nursing in the poor family which is an essential unit in the nursing field of the community and to which a fundamental approach is need as a top priority. We can make such a study, though partially, by revealing the relationship among the Health-value, Health Locus of Contol, and the Level of Self esteem. We randomly sampled 243 women who are participating in the nursing department of the comnnity nursing centers in Seoul. We investigated by using questionaries and made an analysis on the result by SAS program. The result of this investigation can summarized as follows : 1. The average age of the subjects investigated is 43.4 and the participation rate in the economic activity is as high as 49.4%. Most of them are paid daily. The average members of the family are 4.28 persons, and 80.2% of which are nuclear families. The type of housing is as follows:51.4% are monthly-rent houses. Rent houses represent 23.5%. And 43.6% of the subjects graduate the high schools 2. The level of self-esteem possessed by the subjects is 37.17. The quality of task performance(3.46) and the morality(3.53) are low as compared with the other qualities. 3. In relation to the locus of control, internality is 22.39, the influence of powerrful others represents 20.24, and the effect of chance occurance is 16.41. 4. The orderings of value scale are the physical and mental health, comfortable life, happiness, mental peace, and pleasure. The lowest order is social recognition. 5. Considering in relation to the self-esteem and the locus of control, we found out that there is a negative relationship among the self-esteem, the influence of powerful others. The lower the level of self-esteem is, the higher the influence of powerful others is. There is also a negative relationship among the detailed items such as the qualities, and the positive attitude. 6. In a significant test in the general characters of the subjects and in the level of self-esteem, we can obtain the follwing results. The higher the economic level is, the higher the level of self-esteem is. And the higher the level of satisfaction with life is, the higher the level of self-esteem is. 7. In the locus of control, the higher the economic level is, the higher the internality is. 8. In the health-level, 75.72% represent the high health -level. And the group which has the low satisfaction with life represents the high level of health-value(81.6%). With these results, we can conclude that the level of self-esteem possessed by the poor women living in the city is high and that they have the multi-dimemsional health-value even though they are living in the poor condtions. Traditionally, the poverty has been recognized as an unfavorale factor in the health care. But this study shows that the poverty is no longer an unfavorale factor and, on the contrary, it has a potential power with which people can improve their health by possessing the high self-esteem and the high health value. The ultimate purpose which the nursing task of the community has is to make the patients keep and improve their own health. So, when the nurses approach the poor patients, the nurses should put an emphasis on the individual responsibilities of the patients, and respect their own health value.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.4
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• pp.135-151
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• 2021

This research attempts to analyze the factors influencing the entrepreneurial intention of employees in manufacturing field. In particular, key factors of entrepreneurship and personal characteristics explain a significant association with the intention to start-up. And study whether R&D support from public enterprise adjusts intention to entrepreneurial Intention. This study conducted a online survey on 292 small and medium-sized enterprise manufacturing employees in May 2020. Using linear regression model and binary logistic model. The main study results are the following: First, among the key factors(innovativeness, proactiveness, risk-taking) of entrepreneurship, proactiveness hardly influenced the opportunity competency. Second, among the factors(risk-taking propensity, locus of control, tolerance for ambiguity) of personal characteristics, locus of control hardly influenced the opportunity competency. Third, opportunity competency(opportunity recognition and opportunity evaluation) had positive influence to entrepreneurial intention. Fourth, the study investigated the mediated effect of opportunity competency. The result showed that among the factors of entrepreneurship and personal characteristics, only two factors that are proactiveness and locus of control were not mediated by opportunity competency. and opportunity evaluation was acted as a mediator between proactiveness and entrepreneurial Intention, compared with opportunity recognition. Lastly, public enterprise's R&D supporting moderated the entrepreneurial intention). Based on the result, the study showed that first, the key factors of entrepreneurship except for proactiveness and personal characteristics(risk-taking propensity, locus of control, tolerance for ambiguity) except for locus of control affect the intention to start-up, repeatedly. This results are explained that employees have not started a business yet. Second, research on start-up suggests the need to analyze factors differentiated before and after the start-ups. Based on the results, entrepreneurship and personal characteristics show that study on the effects of start-up intentions should be carried out before and after the actual start-up takes place, and can be used as effective data in policies to promoting start-ups in manufacturing field.

• KDI Journal of Economic Policy
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• v.37 no.2
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• pp.1-21
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• 2015

The creation of S&T knowledge and development of S&T- based innovation has spread worldwide from traditionally advanced countries to traditionally developing countries, often under the direction of governments. Korea is an exemplar in this new locus. Korea's burst in Science and Technology during the last three decades has made Korea a substantive player in the global production of S&T knowledge and its application to business. Although Korea still trails the US and other top countries in the quality of research, it has leaped from its 1980s standing as bit player in the knowledge economy to being among the leaders in the early 21st Century. This paper shows that Korea's advance benefited from its active participation in the global market in higher education, in international research collaborations, and its close ties to the U.S. Korea's experience offers lessons for other countries who seek to advance by becoming knowledge economies. Korea proves that a developing country can gain comparative advantage in knowledge production and use; that government policy can stimulate such a development; and that openness to the world of higher education and research is the best way to move forward and overcome the middle income trap.

• Journal of the Korean Home Economics Association
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• v.36 no.1
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• pp.157-168
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• 1998

An education program for parents has been developed in order to meet the needs of those who have problems in rearing their children. The program has been applied two times to a middle size group of parents who live in the urban and the country. The effectiveness of the program has been evaluated by taking pre- and post-tests. The test results suggest that the program has been effective in improving the parent's knowledge on all of the following areas, such as, developmental characteristics, individual traits, learning attitudes cultivation, sex education, locus of self control, parenting behavior and communication skills.