• Korean Journal of Veterinary Service
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• v.32 no.2
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• pp.171-176
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• 2009

Johne's disease is a chronic inflammatory bowel disease of cattle, sheep, goats and other ruminants, and Mycobacterium paratuberculosis is the etiologic agent of this disease. Many studies have been carried out on paratuberculosis from daily cattle and Korean native cattle in multiple areas around nation, but there is no report in Eastern-Gyeongbuk area. The purpose of this study is to investigate the seroprevalence of bovine paratuberculosis in Eastern-Gyeongbuk area. From July to December in 2007, blood samples were collected from 363 dairy cattle of 27 farms and 281 Korean cattle of 114 farms and the ELISA was conducted. 25 (6.9%) dairy cattle of 6 (22%) farms and 19 (6.8%) Korean cattle of 8 (7.0%) farms were positive in ELISA. In regional analysis, 25 (8.3%) out of 300 dairy cattle in Gyeungju were positive and Pohang were negative in this research. 12 (16.4%) out of 73 Korean cattle in Gyeungju and 7 (9.6%) out of 73 Korean cattle in Uljin were positive. Pohang and Youngdeok of Korean cattle were negative in this research. According to raising scale of dairy cattle, 4 (66.7%) farms out of 6 farms were raising 30 below and 2 (33.3%) farms out of were raising 30$\sim$70. And there were negative raising scale more than 70. In Korean cattle, 6 (75%) farms out of 8 were raising below 10 and 2 (25%) farms were raising 10$\sim$30. And there were negative raising scale more than 30. The rate of seropositive of paratuberculosis dairy cattle and Korean cattle were similar and the positive rate of Eastern-Gyeongbuk area is reported lower than that of any other region.

• Journal of Energy Engineering
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• v.22 no.3
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• pp.287-293
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• 2013

This study was carried out to diminish the formation of scale in boilers which is one of the defect elements when they are operating. The defect relating to scale can cause a fatal impact on the explosion of boilers due to the overheating of their tubes, or it can affect the flow of water inside boilers with its bad circulation and result in a disparity of water inside the equipment. Heat transfer in the scale is low comparing to the boiler material, so it can lead to energy losses and has also impact on the global warming. In 2005, the Korean government introduced a system which requires boiler users to install the equipment which can prevent or eliminate the formation of scale to improve the management of water quality in boilers. The study on the techniques for preventing or eliminating the formation of scale started in 1821 and since then subsequently there have been lots of similar studies. The first one was about the scale reduction using potato starch. Since an ultrasonic scale preventer developed by a scientist from a Russian acoustic institute was introduced in1993, a variety of equipment of this kind have been disseminated in Korea. There has been a need to demonstrate the condition for the best performances of such equipment. Boilers are mostly composed of the main body and 288 the tube with a circular curved surface. I carried out a demonstration study on a circular tube which affects the scale defect the most among the boiler components. As a result of it, I found out the fact that the ultrasonic wave needs to reach a certain level of sound pressure and frequency to affect the formation of scale.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.5
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• pp.303-305
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• 2003

Scale-up of hirudin production from Saccharomyces cerevisiae from bench-scale to pilot-scale was carried out based on constant volumetric oxygen transfer coefficient (K$\sub$L/a). Fed-batch mode of cultivation using step-wise feeding strategy of galactose was employed for the production of hirudin in a 30-L and a 300-L pilot-scale fermentor. The final hirudin concentrations were achieved 390 mg/L and 286.1 mg/L, and the volumetric productivities were 80.4% and 90.7% with the 30-L and 300-L fermentors, respectively, compared to the productivity of the 5-L bench-scale fermentor.

• Journal of dental hygiene science
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• v.18 no.5
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• pp.271-279
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• 2018

This study aims to contribute to managing the human resource of dental hygienists and qualitatively enhancing dental medical services by examining factors that affect their turnover intention. Therefore, it attempted to examine their degrees of emotional labor, job satisfaction, and social support and the effects of each variable on turnover intention. This study administered self-reporting questionnaires to dental hygienists working in dental hospitals, dental clinics, and general or university hospitals in Seoul Metropolis and Gyeonggi-do by conducting convenience sampling, from May 18, 2017 to August 4, 2017. Among a total of 224 copies that were distributed, a total of 223 copies, excluding 1 copy with poor responses, were used in the data analysis. The research tools comprised 12 questions on general characteristics, 24 questions on emotional labor (4-point Likert scale), 16 questions on job satisfaction (5-point Likert scale), 8 questions on social support (4-point Likert scale), and 4 questions on turnover (5-point Likert scale). The scores of dental hygienists were as follows: emotional labor, 2.49 out of 4; job satisfaction, 3.14 out of 5; social support, 3.04 out of 4; and turnover intention, 3.07 out of 5. Their turnover intention has a positive correlation with emotional labor, but a negative correlation with job satisfaction and social support. It was found that some factors that significantly influence turnover intention included the amount of overtime work and job satisfaction. Thus, dental medical institutes should search for measures, including improvement of the working environment, to reduce the amount of overtime work and enhance job satisfaction.

• The Journal of the Korea Contents Association
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• v.12 no.2
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• pp.232-242
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• 2012

The purpose of this study was to analyze the multiple regression between the psychological well-being, Empathy ability Scale and Job Efficiency at relationship among on Teacher's job satisfaction among elementary, middle, high the whole country. It aims to find a method that can improve teacher's job satisfaction. The subjects for this study were 308 teacher's composed of 196 out of elementary school teachers, 62 out of middle school teachers and 50 out of high school nation wide. The result and discussion are as follows:First, if we take a look teacher's psychological well-being, Empathy ability Scale and Job Efficiency autonomy and school administration, compensation system, personal growth and school administration, compensation system, working environment, purpose of life and school administration, positive interpersonal relationships, self acceptance among subordinate variables of psychological well-being, empathy ability scale, job efficiency of teachers at are all relevant to of subordinate variables except compensation system. Second, as a result of the multiple regression analysis, the significant variables which affect teacher's job satisfaction are ranked in the order of human relationships, self acceptance, emotional factors. whole all variables are not significant.

• Journal of the Korean Geotechnical Society
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• v.29 no.1
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• pp.121-133
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• 2013

This paper presents the results of an investigation into the pull-out capacity characteristics of screw anchor piles. Theoretical background of screw anchor pile (SAP) was first discussed. A series of reduced-scale model tests were performed on a number of cases with different SAP geometries such as pitch and diameter of screw as well as relative density of the model ground. The applicability of the pull-out capacity prediction equations were also examined based on the test results. It was shown that the pitch of screw has negligible effect on the pull-out capacity, while the diameter of screw has relatively large effect on pull-out capacity under a given condition. Practical implications of the findings from this study are discussed in great detail.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.6
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• pp.445-452
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• 2014

This paper discusses the multifrontal direct solution method with out of core storage for large scale structural analysis in a limited computing resource. Large scale structural analysis requires huge amount of memory space and computation, so out of core solution method is needed in limited computing resource. In this research, out of core multifrontal solution algorithm which utilize the small size of physical memory and minimize the amount of access of low speed out of core storage is introduced. Three ideas, which are stack space in lower trianglar part of square factorization matrix, inverse stack data structure and selective data caching and recovery by data block size, are proposed.

• Journal of the Korea Society of Computer and Information
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• v.22 no.9
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• pp.187-192
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• 2017

In this paper, we have studied scale tools for measure programming task value and learning persistence at elementary school students. In order to develop complete test tools, we have improved the completeness by revising tests through stepwise verification. The first scales were constructed based on the previous studies. As a result of the content validity test, 5 out of 14 items of the task value test tool and 1 out of 10 items of the learning persistence test were not suitable. The second test tools were constructed by revising and supplementing the first scale, and consisted of 13 items of task value and 8 items of learning persistence. As a result of the contents validity test, all the items included in the test tool proved to be valid. The reliability of the secondary testing tools were also found to be reliable at ${\alpha}=.970$ and ${\alpha}=.975$, respectively.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.313-318
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• 2004

When plan breakdown by permeation of fill dam, bank by original decision scale model test of sound, original decision scale model test of sound that destroy having used water was carried out. And original decision scale model test of sound that use viscous fluid is carried out, but doubt remains in experiment result in state that verification of law of similarity is not achieved. In this study, verified according to Modeling of Models' method effecting law of similarity to use n ship horoscope solution of water.

• Computers and Concrete
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• v.19 no.4
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• pp.375-385
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• 2017

In the present paper experimental and numerical analysis of hook-ended steel fiber reinforced concrete is carried out. The experimental tests are performed on notched beams loaded in 3-point bending using fiber volume fractions up to 1.5%. The numerical analysis of fiber reinforced concrete beams is performed at meso scale. The concrete is discretized with 3D solid finite elements and microplane model is used as a constitutive law. The fibers are modelled by randomly generated 1D truss finite elements, which are connected with concrete matrix by discrete bond-slip relationship. It is demonstrated that the presented approach, which is based on the modelling of concrete matrix using microplane model, able to realistically replicate experimental results. In all investigated cases failure is due to the pull-out of fibers. It is shown that with increase of volume content of fibers the effective bond strength and slip capacity of fibers decreases.