• Korean Journal of Materials Research
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• v.4 no.1
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• pp.3-8
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• 1994

Recently, sound and mechanical vibration are becoming important problems in our life. In the present study, the measurement of vibration absorption characteristics of barium titanate ceramics and the investigation of its relationship to microstructures were carried out. The barium titanate ceramics is expected to be better vibration absorption material owing to its chemical and physical stability than other conventional vibration absorbers like glasswool board. Barium titanate ceramics were prepared by sintering fiberous $BaTiO_{3}$ crystallites in order to enhance the vibration absorption characteristics. The fiberous $BaTiO_{3}$ ceramics were prepared through the ionic exchange after the preparation of fiberous $K_2Ti_4O_9$ with 0.2$\mu\textrm{m}$, 1.2$\mu\textrm{m}$, 2.0$\mu\textrm{m}$, diameter length by KDC method. The fiberous crystallites were oriented in a plane perpendicular to the press direction and sintered. The investigation of the grain diameters of the sintered ceramics, equivalent factor, electromechanical coupling factor($k_1$), and the generated voltage(V) shows that the grain's diameter decreases with the increase of the diameter of the used fiberous crystallites. The vibration absorption increases the crystallites' diameter. That means that the vibration absorption increases with the internal friction of grain boundary. Which was identified by the investigation of the equivallent circuit.

• Research in Community and Public Health Nursing
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• v.13 no.1
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• pp.161-170
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• 2002

Purpose: To evaluate community health nursing practice by nursing students for basic data to improve nursing practice education, and to determine the clinical practice experiences of nursing students at public health centers. Method: According to methodological triangulation, all data was collected from March 2001 to June 2001 through prepared questionnaires with 62 Participants, and in depth interviews with 2 Participants, and content analysis with 8 Participants. Results: 1. Clinical practice content was needed to make up professionally. 2. Clinical practice instructor was satisfied with teaching by community health nursing professor, but not by public health center nurse. 3. Clinical environment was perceived as good. 4. Clinical practice time was perceived suitable, but practice evaluation was given a low grade. 5. Experience of nursing students was grouped into 9 categories and 20 themes. 9 Categories are as follows: change of public health center image, difficulty in the personal relationship, positive personal relationships, doubt about the attitude, doubt about the task, tension, worth, ambivalance of the conference, feeling about the end stage of the clinical practice. Twenty themes are stereotypic of the public health care center: recognition, difficulty between tasks and interrelationships with the clients, decrease of self esteem due to deficiency of trust with the students, exchange of feelings in the relationships, the situation of clients was not considered, feelings were disregarded, not systematic, regarding students as supplementory manpower, independent work but not enough contents, anxiety & fear, self-trust, be skilled in the practice, pragmatic knowledge formation, understanding of the old person, self-study of oneself. live up to the expectation, consider as the job, dissolve the stress and impose burden, feeling the lack regarding active approach in the practice. Conclusion: The students have perceived the need of community health nursing through the clinical practice. Clinical practice of community health nursing requires content supplement, correction of instruction by public center nurses, environmental alteration, evaluation criteria set up. Experience of clinical practice in the public health center was as follows: Getting rid of the stereotype about public health center, nursing students comprehended variety and were worth while to do clinical practice in spite of tension& anxiety and fear. And they thought to be a community nurse someday.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.16 no.2
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• pp.33-56
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• 2005

The purpose of this study is to understand the critical role of customers' perceived service quality. in relationship marketing. This paper examined the relationships of service quality with customer satisfaction, and investigated the effects of trust and commitment. Data were collected from 242 people at hotel located in Taegu city. LISREL provided satisfactory model-fits in measurement model and structural equation model. The empirical results indicated that first, service quality takes strong effect on customer satisfaction and trust but not on commitment. Second, trust and commitment are importantly influenced by customer satisfaction. Third, service quality was found to indirectly contribute to trust and commitment. Finally, customer satisfaction is effective mediators linking service quality to trust and commitment. The effects of these variables on trust and commitment, which are based on social exchange theory, were empirically confirmed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.3
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• pp.337-345
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• 2018

The purpose of this study is to analyze the relationship between the characteristics of Korean family firms and the impact of debt financing. The analysis period was 10 years from 2004 to 2013, and the sample consisted of 4,008 non-financial firms listed on the Korea Exchange. For the analysis, the unbalanced panel data with time - series, cross - section data were formed and analyzed using panel data regression analysis. The results are as follows. First, Korean family firms use relatively less debt than non - family firms. It can be understood that family firms in which the dominant family owns and dominates the corporation are less likely to increase their debt because the agent problem is alleviated and the need for the control effect of Jensen (1986) is lowered. Second, in the verification of the packing order theory using the model proposed by Shyam-Sunder and Myers (1999), family firms have higher compliance with the packing order theory than non-family firms do. When financing is needed, debt is preferred over equity issuance. However, for Korean family firms, 24.38% of the deficit funds are financed through the issuance of net debt, which is relatively low compared to the 75% shown in the analysis of Shyam-Sunder and Myers (1999). These results reveal the limit to the strong claim that the Korean family firms follow the packing order theory.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.1
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• pp.119-129
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• 2018

Companies' efforts to secure and sustain a competitive advantage in the market may also appear in the form of new product development. This has increased the importance of leveraging knowledge from other companies in a global competition that is accelerating with an accelerating product life cycle and the development of transportation and communications. In order to create valuable knowledge through the exchange and combination of knowledge, the absorptive capacity of the recipient of the knowledge should be considered as important, but also the knowledge protection tendency, which is characteristic of the knowledge transferor, should be considered. However, studies that considered these factors at the same time were very limited. This study examines the effect of suppliers 'absorptive capacity and buyer' s knowledge protection on new product development performance during the joint development of new products. In addition, we investigated the interaction effect between supplier's absorption capacity and buyer's knowledge protection tendency. For this purpose, data were collected for automobile industry, electronics industry and defense industry, where joint development of new products occurred frequently, and statistical verification was performed by regression analysis. The results showed that the absorptive capacity of the supplier was positively correlated with the performance of the new product development, and the buyer 's knowledge protection tendency had a negative relationship with the new product development performance. In addition, the absorptive capacity of the supplier and the buyer 's knowledge protection tendency have an interaction effect on the new product development result. These results suggest that suppliers' absorption capacity is an important factor in the joint development of new products, but suppliers with superior absorption capacity may have a negative impact on new product development performance if buyers have a negative attitude toward knowledge transfer.

• Journal of Chest Surgery
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• v.13 no.2
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• pp.85-91
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• 1980

Extracorporeal circulation by hemodilution technique has been currently used with its clinical safety and good peripheral tissue perfusion in open heart surgery. There is no doubt that $O_{2}$ carrying capacity of the blood is disturbed by decreased hemoglobin level resulting from hemodilution of the circulating blood. From the view point of the blood gas exchange, these experimental studies were undertaken to determined the sate limit of hemodilution in the condition of cardiopulmonary bypass with a constant perfusion flow rate. Twelve adult mongrel dogs weighing 10 to 13 Kg. were anesthetized with pentobarbital and then respiration was controlled with Harvard volume respirator using room air. The cardiopulmonary by pass was performed by use of Sarns heart lung machine (console 5000, 5 head and 2 roller pumps) and Travenol pediatric bubble oxygenator. The perfusion rate during bypass was maintained at a constant rate of 80 ml/min/Kg of body weight. The ratio of oxygen gas flow to blood flow was kept in 3 to 1 constantly. International hemodilution was attained by serial blood withdrawals and immediate infusion of equal volumes of diluants composed of Ringer's lactate, 5% dextrose in water and 25% mannitol solution, proportionally 60%, 30%, and 10%. Arterial and venous blood samples were obtained between 15 and 20 minutes following each hemodilution. Hematocrits and hemoglobin values, $PO_{2}$, $PCO_{2}$ and pH were measured. Oxygen and carbon dioxide contents oxygen consumption and carbon dioxide elimination were calculated groups according to different hematocrit values and the correlations were evaluated. Result were as follows. 1. the arterial $O_{2}$ tension and $O_{2}$ saturation were maintained at the physiological level irrespective of the hematocrit value. 2. The venous $O_{2}$ tension and $O_{2}$ saturation showed a tendency to decline with the decrease in hematocrit value and positive correlation between them (r = +0.49, r = +0.76), The mean values of venous $O_{2}$ tension and $O_{2}$ saturation, however, were not decreased when the hematocrit levels were lower than 20%. 3. The arterial $O_{2}$ content declined lineally in proportion to the fall of hematocrit level with a positive correlation between them (r = +0.95). 4. The venous $O_{2}$ contents were decreased gradually as the hematocrit value decreased with positive correlation between them ( r =+0.89). The trend of diminution of venous $O_{2}$ content, however, was became low according to progressive decrease of hematocrit level. 5. Systemic oxygen consumption was in higher range than $O_{2}$ requirement of basal metabolism when the hematocrit value was above 20%, but abruptly decreased when the hematocrit value became to below 20%. 6. The arterial $CO_{2}$ tension and $CO_{2}$ content showed trend of increasing with progressive decrease of hematocrit value but exhibited a rather broad range and there was no relationship between those value and the hematocrit value. 7. The venous $CO_{2}$ tension and $CO_{2}$ content have also no correlation with change of Ht. value but related directly to those value of arterial blood with positive correlation between them (r = +0.78, r = +0.95_. 8. A-V difference of $CO_{2}$ content and $CO_{2}$ elimination wasnot significantly influenced by Ht. value. From the results, we obtained that feasible limit in inteneional hemodilution is above the hematocrit value of 20% under the given experimental condition.

• Journal of the Korean Society of Safety
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• v.32 no.4
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• pp.46-52
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• 2017

Sediment exchange in river has been affected by artificial changes such as dredging and abnormal climate changes like intense rainfall. Over last decades in Korea, there were many constructions, restoration or rehabilitation in rivers. Therefore, deposition and erosion become more actively occurred than before, which may threaten the river safety such as flood defense. For safety's sake, the dredging of river bed, which is considered as the most typical measure, has been increased to extend hydraulic conveyance compared with previous conditions. However, since it might change the sediment mechanism, there would be another risk at which unexpected side effects such as headward erosion could be occurred. Particularly, sedimentation at abrupt expansion region is able to lead to hydraulic characteristics like water elevation in the upstream region in the beginning of dredging, which, however, has been barely studied in this field. Therefore in this study, the relationship between sediment mechanism at dredging section and hydraulic characteristics in upstream region were presented through numerical simulations in the idealized abruptly widen channel using Delft3D. The ideal channel of 2,000 m length with each side angle of 45 degrees at abruptly widen expansion region was employed to consider the sediment angle of repose. The sensitivity analysis was performed on the dimensionless factors consisted of upstream and downstream depths($h_u$, $h_d$), width($w_u$, $w_d$), water level(H), flow rate(Q) and discharge of sediment($Q_s$). And the sedimentation amount at dredging and the upstream hydraulic characteristics were investigated through that analysis. It showed that $h_d/h_u$, $H/h_u$ and $w_d/w_u$ were more influential in sequence of effect on sedimentation amount, while $h_d/h_u$, $w_d/w_u$ and $H/h_u$ on upstream region. It means that $h_d/h_u$ was revealed as the most significant factors on sedimentation, also it would most highly affect the rising of water level upstream.

• The Journal of the Korea Contents Association
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• v.10 no.8
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• pp.327-340
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• 2010

Since South Korea has problems existing in the respects of educational resources, environment, policies, etc., local universities of South Korea have been in an inferior position in the competition of overseas student enrollment. With increasingly deepening of cultural exchange between China and South Korea, due to geographic close relationship between the two countries, a great number of South Korean students go to China for study; also, Chinese students have increasingly become the important target of recruitment by all local universities in South Korea. In recent years, with rapid increase in the number of Chinese students in South Korea, the overseas student education system of South Korea has been progressed continuously. Compared with educational advantages of universities in European, American developed countries, and the capital region of South Korea, however there still exists a lot of problems in Chinese student recruitment by local universities. The major findings of the study can be summarized as follows. There exist not only some advantages but also some problems to be addressed urgently in Chinese student enrollment by South Korean local universities. How to build a distinctive recruitment environment suitable for Chinese students; and, how to develop a complete "one-stop" educational system suitable for study; and, how to make a strategy of development for Chinese students; and, how to perfect set up the overseas students' education management system; which are the remaining tasks to be solved for. To achieve a win-win for both overseas students and South Korean local universities, it is very important and urgent works to do for administrators of Chinese students in all local universities of South Korea.

• The Journal of the Korea Contents Association
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• v.16 no.10
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• pp.163-174
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• 2016

This study is intended to check the empathy and cultural competence of female college students majoring in aviation and tourism service. The number of study subjects was 274. And the descriptive statistics, t-test, ANOVA, Scheffe test, and pearson correlation coefficient of data was analyzed through SPSS 20.0. According to the results of study, an average mark of empathy was $3.72{\pm}0.35$, and an average mark of cultural competence was $3.48{\pm}0.47$. When the level of difference in empathy and cultural competence was examined according to the general characteristics, the level of empathy showed a significant difference in the purpose of visiting foreign countries and foreign language skills. And the level of cultural competence showed a significant difference in religion, foreign language skills, foreign friend, experience in international exchange, experience in cultural education abroad, a method of cultural education abroad, and a necessity for cultural education abroad. With regard to correlation, there was a positive correlation between empathy and cultural competence(r=.425, p<.001). And in case of sub-attribute, it was shown that the cognitive factor and emotional factor of empathy has a positive correlation with cultural competence. It was verified that an education plan making it possible to improve cultural competence is required by checking a mutual relationship between empathy and cultural competence through these study results.

• Journal of Microbiology and Biotechnology
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• v.30 no.4
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• pp.505-514
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• 2020

The symbiotic nature of the relationship between algae and marine bacteria is well-studied among the complex microbial interactions. The mutual profit between algae and bacteria occurs via nutrient and vitamin exchange. It is necessary to analyze the genome sequence of a bacterium to predict its symbiotic relationships. In this study, the genome of a marine bacterium, Pseudoruegeria sp. M32A2M, isolated from the south-eastern isles (GeoJe-Do) of South Korea, was sequenced and analyzed. A draft genome (91 scaffolds) of 5.5 Mb with a DNA G+C content of 62.4% was obtained. In total, 5,101 features were identified from gene annotation, and 4,927 genes were assigned to functional proteins. We also identified transcription core proteins, RNA polymerase subunits, and sigma factors. In addition, full flagella-related gene clusters involving the flagellar body, motor, regulator, and other accessory compartments were detected even though the genus Pseudoruegeria is known to comprise non-motile bacteria. Examination of annotated KEGG pathways revealed that Pseudoruegeria sp. M32A2M has the metabolic pathways for all seven vitamin Bs, including thiamin (vitamin B1), biotin (vitamin B7), and cobalamin (vitamin B12), which are necessary for symbiosis with vitamin B auxotroph algae. We also identified gene clusters for seven secondary metabolites including ectoine, homoserine lactone, beta-lactone, terpene, lasso peptide, bacteriocin, and non-ribosomal proteins.