• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.23 no.1
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• pp.71-85
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• 1993

The purpose of the study was to investigate the effects of the single and fractionated irradiation on the microvascular structure of the submandibular gland in rats. For this study, 90 Sprague-Dawley strain rats were irradiated to their neck region with equal split doses of 9Gy for a 4 hours interval and 15Gy single dose by 6MV X-irradiation and sacrificed on the 1st, 3rd, 7th, 14th and 27th day after irradiation. The author observed histological changes at Hematoxylin and Eosin staining and PAS staining under a light microscope, and also observed distribution and structural changes of the microvasculature in rat submandibular gland using a scanning electron microscope by forming vascular resin casting. The results were as follows: 1. In the light microscopic examination, the microvasculature was slightly dilated and decreased in number on the 1st day after irradiation, and increase in number of microvasculature was observed on the 3rd day after irradiation. And then distribution of microvasculature was markedly increased on the 7th day after iradiation, but decreased on th 14th day after irradiation again. Such changes were greater in the single irradiated group than in the fractionated irradiated group. 2. The reaction to PAS staining on glandular cell was decreased on the 1st and the 3rd day after irradiation, and recovered on the 7th day after irradiation. The reaction was decreased on the 14th day after irradiation again, and recovered on the 28th day after irradiation. Changes were more apparent in the single irradiated group. 3. In the scanning electron microscopic examination, early changes of microvasculature were decreased capillary density, dilation of conduits and meandering. Increased capillary dentsity or anastomosis due to vascular reproduction and smooth curved running were observed on the 7th and 14th day after irradiation. Decreased capillary and smooth running tendency were observed on the 28th day after irradiation again. Such changes were greater in the single irradiated group than in the fractionated irradiated group.

• Korean Journal of Community Nutrition
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• v.5 no.2
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• pp.225-235
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• 2000

Service quality has become an important factor to meet customer satisfaction in the food service industry where competition is getting severe. Organizations are focused upon strengthening customer loyalty through customer satisfaction. Therefore, this study, taking customers as subjects, is intended to analyze factors affecting customer loyalty, on the basis of service quality satisfaction. In doing. so, the analysis has been done with 232 customers who are purchasing service from the food services industry, for general information, and service quality expectation, service quality satisfaction and overall satisfaction. The results of the study are as below. 1) From a factor analysis, the service quality expectation level of customer has been categorized into 4 factors, which are named General ′General management ′, ′Food′, ′Reliability′and ′Reputation′. 2) From the factor analysis, the service quality satisfaction level of customer has been categorized into 6 factors, which are named ′Employee attitude′, ′Food′, ′Reliability′, ′Atmosphere′, ′Reputation′ and ′Price′. 3) After classifying customers into 3 groups according to two criteria-"will buy the service again" and "will suggest to others", a comparison has been done for the service quality expectation dimension of customers by each customer group. The result shows that the group having both the "will buy the service again" and "will buy the service again "and "will suggest to others" criteria, that is, with higher customer loyalty, tend to have higher point than other group in factors of ′Food′, ′Reliability′, ′Reputation′(p〈.05). 4) As per the dimension of customer\`s service quality satisfaction level, factors like ′Employee attitude′, ′Food′, ′Reliability′, ′Atmosphere′, ′Reputation′, and ′Price′have shown differences according to each loyalty group(P〈.001). 5) Customers′overall satisfaction level according to each customer loyalty group has been found to be more important for the group having a higher loyalty level(p〈.001) 6) From the discriminant analysis with employing judging variables, such as the customer′s service quality expectation level, service quality satisfaction level and general satisfaction level, customer loyalty groups have been identified as accurately as 68.9% of the explanatory power.

• Korean Journal of Social Welfare Studies
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• v.47 no.4
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• pp.183-216
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• 2016

This study aims to investigate the career development experience of youth in late adolescence who entered a different university after taking a semester off (as known as Bansu in Korean), in depth, applying a phenomenological research method. For the research, this study selected seven adolescents as research participants to reveal the essential meaning of their experience, vividly. The data were analyzed by Giorgi's method to draw components of the experience of research participants. As a result of the research, the career development experience of youth in late adolescence who entered a different university after taking a semester off was systematized into 19 sub-categories and structured into four main categories: "high school years in which academic record was more important than aptitude", "the step away from the dream, being forced to proceed to college", "the time of study to take the exam again, which was an advantage and disadvantage at the same time" and "the wish unfulfilled even with the success of entering a different university." It turned out that the main topic was "the repeated way even after passing the repeat sign." They took the College Scholastic Ability Test (CSAT) once again and came back to the narrow way to enter a prestigious university, but they still compromised the standard made by the older generation. This study has significance for late adolescents' welfare and happiness in that it explored the in-depth meanings of the career development experience of youth who entered a different university by taking the CSAT again after taking a semester off. Lastly, based upon the situation of the increase in the number of students who take the CSAT again, this study suggested better measures for career development during adolescence and the promotion of their quality of life.

• JOURNAL OF ELECTRICAL WORLD
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• s.449
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• pp.86-91
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• 2014

경남지역은 해안, 도서, 산악지역, 도심지, 대규모 발전단지, 대형 산업단지, 태풍의 경로 등 그야말로 전력회사가 접할 수 있는 모든 특수한 상황이 산재해 있는 독특한 지역이다. 이는 경남지역의 안정적 전력공급을 책임지고 있는 한전 경남지역본부가 능수능란한 대처 능력을 충분히 갖추고 있어야 한다는 것을 의미한다. 다양한 현안을 탁월한 수행능력으로 대처하며 'AGAIN KEPCO! BRAVO 경남' 달성을 위해 경주하고 있는 한전 경남지역본부를 찾았다.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.156.2-156
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• 2001

Hypersonic civil airplanes are recently heated up again in USA and Japan, but there are several difficulties when we obtain its optimal trajectories. In this paper, we formulated the trajectory optimization problem as an optimal control problem and solved it by the direct shooting method with the Genetic Algorithm, GA. The result shows it is effective to use this method for the trajectory optimization of the hypersonic flight.

• Honam Mathematical Journal
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• v.28 no.2
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• pp.221-224
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• 2006

A Kummer-type transformation formula for the generalized hypergeometric function $_2F_2$ deduced by Exton, rederived in two simple and transparent ways by Miller and generalized by Paris, is again derived by another method.

• Journal of the Korean Statistical Society
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• v.36 no.3
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• pp.349-355
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• 2007

In this paper we study some important properties of the bivariate generalized hypergeometric probability (BGHP) distribution by establishing the existence of all the moments of the distribution and by deriving recurrence relations for raw moments. It is shown that certain mixtures of BGHP distributions are again BGHP distributions and a limiting case of the distribution is considered.

• Journal of the Korea Society of Computer and Information
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• v.21 no.5
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• pp.141-148
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• 2016

In this paper, we propose a topic network analysis approach which integrates topic modeling and social network analysis. We collected 2,039 scientific papers from five top journals in the field of data mining published from 1996 to 2015, and analyzed them with the proposed approach. To identify topic trends, time-series analysis of topic network is performed based on 4 intervals. Our experimental results show centralization of the topic network has the highest score from 1996 to 2000, and decreases for next 5 years and increases again. For last 5 years, centralization of the degree centrality increases, while centralization of the betweenness centrality and closeness centrality decreases again. Also, clustering is identified as the most interrelated topic among other topics. Topics with the highest degree centrality evolves clustering, web applications, clustering and dimensionality reduction according to time. Our approach extracts the interrelationships of topics, which cannot be detected with conventional topic modeling approaches, and provides topical trends of data mining research fields.

• Imaging Science in Dentistry
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• v.43 no.3
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• pp.201-207
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• 2013

A 40-year-old man suffered from a repeatedly recurrent desmoplastic ameloblastoma in the right maxillary anterior and premolar regions. During the first visit, the patient was provisionally histopathologically diagnosed with a developmental cyst, and it was confirmed to be unicystic ameloblastoma and resected. Four years later, the lesion recurred, and was diagnosed as a desmoplastic type of ameloblastoma and removed again. Then, 5 years after the second surgery, the lesion recurred again, and was diagnosed as a type containing a follicular pattern, recurrent ameloblastoma. A panoramic radiograph showed a multilocular and mixed radiolucent/radiopaque expansile lesion at the first visit, a unilocular cystic lesion confined to the premolar area at the second visit, and a small soap bubble appearance in the molar area in the final visit. Cone-beam computed tomographic images of the final recurrence of the tumor revealed multiple small cyst-like structures in the right maxillary anterior and posterior regions.

• Journal of Engineering Education Research
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• v.3 no.1
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• pp.84-91
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• 2000

Modern times are called 'the system and fusion era'. One system has been compounded with the other system repeatedly, and the new systems form a great mixed system again and again. Discrete electronic devices have been integrated as one semiconductor system and have been unified as a great mixed system frequently. This study proposes a module based 2-year college electronic engineering curriculum focused on system and integrated circuit design. This curriculum is devised to be suitable for the industrial environment, especially in the school-industry cooperation, and is recomposed to promote the organic union of interdisciplinary courses. The newly designed course has been developed as a multi semester module model which enables a practical field training and in-depth study.