• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.5
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• pp.375-380
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• 2017

This paper reports the results of an acceleration test to predict the contact-induced failure that could occur at the cylinder-to-hole joint for the fuel rod of a sodium-cooled fast reactor (SFR). To incorporate the fuel life of the SFR currently under development at KAERI (around 35,000 h), the acceleration test method of reliability engineering was adopted in this work. A finite element method was used to evaluate the flow-induced vibration frequency and amplitude for the test parameter values. Five specimens were tested. The failure criterion during the life of the SFR fuel was applied. The S-N curve of the HT-9, the material of concern, was used to obtain the acceleration factor. As a result, a test time of 16.5 h was obtained for each specimen. It was concluded that the $B_{0.004}$ life would be guaranteed for the SFR fuel rods with 99％ confidence if no failure was observed at any of the contact surfaces of the five specimens.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.6
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• pp.796-802
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• 2018

The effects of inner liquid sloshing on vessel motions are a well-known factor. It was investigated experimentally and numerically. In this regard, the study of many efforts to reduce natural phenomena of vessel motions by adopting special devices especially for roll motions. Among many devices, inserting baffles in the inner liquid tank is very common. In this study, one investigated the vessel motions with inner sloshing tanks with baffles inside. For the numerical simulation, one employed a dynamically coupled program between boundary-element-method-based vessel motion analysis program and a particle-based computational fluid dynamics program. Comparing corresponding experimental results validated the dynamically coupled program. The validated coupled program was used to simulate vessel motions, including sloshing effects with various lengths of inner baffles. The simulation results show that not only the filling ratio of inner liquid, but also the length of clearance due to baffles influenced the vessel motions. The significant point of this study was that the natural frequency of vessel motions can be maintained irrespective of the amount of filling ratio through adjustment of the clearance. In a future study, the effects of various numbers of baffles with various clearances would be conducted to percuss the possibility of vessel motion control with inner liquid sloshing effects.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.3
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• pp.1347-1350
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• 2016

Background: Breast cancer prognosis is influenced by several histopathology and clinical factors including expression of Ki67 which may have a predictive role in lymph node negative breast cancer patients. The aim of this study was to assess Ki67 expression in breast cancers without axillary lymph node involvement and to evaluate its prognostic value with regard to disease-free survival. Materials and Methods: Subjects were selected from non-metastatic invasive breast cancer patients who were referred to the oncology department of Ghaem hospital during 1 April 2001 to 1 April 2008. Ki67 levels were measured using immunohistochemistry (IHC) and compared with clinicopathological features. The relation of Ki67 expression with disease-free survival was also analysed. Results: A total of 106 women with a mean age of 49 were examined. Some 94.3% were classified as having invasive ductal carcinomas and the mean tumour diameter at the time of diagnosis was 2.8 cm. Some 50.9% of cases were ER positive and 47.2% were PR positive. P53 expression was positive in 48.1% of the cases. According to the IHC results, only 8.5% of the patients were Her2/neu positive. Ki67 was positive in 66 (62.3%) with a significant relation to lower age (p=0.0229) and P53 positivity (p=0.005). After an average of 40-months follow up, 13 (12.3%) demonstrated recurrence, most commonly systemic. Of 13 cases with relapse, 10 patients (77%) were Ki67 positive. Conclusions: In our population Ki67 appeared to be an independent prognostic factor for three-year survival. However, we stress that a survival study with a bigger sample size would help to support this conclusion.

• Industry Promotion Research
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• v.2 no.1
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• pp.39-44
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• 2017

The purpose of this study is to analyze the effect of the Naeil Chaeum deduction system on job satisfaction. The results of the study are summarized as follows. A total of 159 small to medium-sized enterprise workers participated in the deduction for Naeil Chaeum. The data were analyzed using SPSS Statistics 20, which included frequency analysis, factor analysis, reliability analysis, correlation analysis, regression analysis, and post analysis. First, the suitability of the method of the Naeil Chaeum deduction system has the highest positive effect on the job satisfaction. Second, the correlation of job satisfaction after filling in Naeil Chaeum deductions showed that fitness (p <.01, ${\beta}=.307$) and efficiency (p <.01, ${\beta}=.296$) had a significant effect on job satisfaction. Third, the analysis of the difference of job satisfaction according to the academic ability of the workers who were enrolled in Naeil Chaeum deduction system was analyzed that professional college graduates (2.08) were higher than job college graduates (1.99).The purpose of this study is to analyze the impact of the Fill - Down System on the job satisfaction by analyzing the importance of quality of life, job satisfaction, and muscle strength, analyzing the difference according to the demographic characteristics of the workers, And helping to stabilize the work life, and to verify the effectiveness of the study.

• Industry Promotion Research
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• v.2 no.1
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• pp.77-83
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• 2017

The purpose of this study is to analyze the effect of sustainability of festival in Gangwon province on satisfaction. A total of 243 questionnaires were analyzed for the tourists participating in the Gangwon - do area festival. Using SPSS Statistics 20, we conducted frequency analysis, factor analysis, reliability analysis, correlation analysis, regression analysis, and ANOVA (Variance Analysis of Variance among Respondents). The results of this study are as follows. First, the satisfaction of the local festival persistence in Gangwondo area festival was found to be higher when the service satisfaction, program satisfaction, and red general satisfaction were higher in the regional festival sustainability. And it was analyzed to have a statistically significant effect. Second, there was no statistically significant effect of participating motivation on the program festival. Third, the correlation between the persistence of local festivals and the satisfaction of the local specialties was higher in R = .812, and the t value was 21.569 (p = .000) Respectively. The purpose of this study was to examine the effect of personal factors on regional festival tourists' satisfaction with regional festival sustainability and participatory motivation for service satisfaction, program satisfaction, There is a significance of research.

• Industry Promotion Research
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• v.2 no.1
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• pp.93-99
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• 2017

This study analyzed the effect of pension insurance on the human resources management of SME workers. As a result of the study, a total of 128 workers were enrolled in 60 SMEs in the Chungnam area who were enrolled in pension insurance. The analysis data were analyzed using frequency analysis, factor analysis, reliability analysis, correlation analysis, regression analysis And post - analysis. First, pension insurance had a significant effect on human resource management, and the correlation between independent variables (clarity, suitability, and satisfaction) and dependent variables (job efficiency) was high....Second, the correlation between pension insurance and job performance is more important than clarity and job performance (.339), fitness and job performance (.541), satisfaction and job performance (.531), job performance and job efficiency, And the turnover intention (.549). Third, there is no statistically significant difference in the analysis of the difference in turnover intention according to the number of years of service of the employees who are enrolled in pension insurance. The purpose of this study is to analyze the impact of pension insurance on human resources management to achieve successful policy objectives by promoting the long - term employment of the core manpower of SMEs and cultivating manpower.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.1
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• pp.42-52
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• 2012

In this paper, a waveguide antenna is designed and fabricated for side and rear radar sensor of vehicles in UWB (Ultra Wide Band) high band (center frequency : 9.5 GHz, -10 dB bandwidth : 600 MHz (6.4 %)). For the radar antenna, a probe fed rectangular waveguide antenna having simple structure and wide bandwidth is used. An important performance factor in this antenna is the isolation between transmitting (TX) and receiving (RX) waveguide antennas because this radar system uses TX and RX antennas separately. Thus the isolation between two antennas was simulated for E-plane and H-plane array. As a result, it was verified that the isolation of the H-plane array of the antennas is better than E-plane array, due to the TE10 mode. Therefore, H-plane arrayed waveguide antennas were mounted on a T-shaped radar module and performance of antennas was investigated. The -10 dB bandwidth of the TX and RX antenna mounted on T-shaped radar module was measured as 1000 MHz (10.52 %) and 1090 MHz (11.47 %) respectively and the isolation is less than -50 dB in the operation band. The peak gain is 7.65 dBi for the TX antenna and 7.26 dBi for the RX antenna and the beamwidth of H-plane of TX and RX antenna was measured as $64^{\circ}$ and $65^{\circ}$ respectively. Consequently, we verified that the proposed waveguide antenna is appropriate for a vehicle radar applications.

• Journal of Agricultural Extension & Community Development
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• v.8 no.1
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• pp.25-40
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• 2001

The purposes of the study were to identify satisfaction and achievement of learning by female learner's characteristics, and to suggest measures to improve quality of education in internet education programs. In order to determine the educational effectiveness associated with the characteristics of learners, this study attempted to employ two way approaches by observing the degree of achievement for learning, which represents an instructor-oriented approach, and the degree of satisfaction for education, which represents a learner-oriented approach to enhance the quality of internet education for female learners. As an approach to evaluate the educational effectiveness, the degree of achievement in learning(Tyler's classical approach), and the degree of satisfaction for education (Scriven's consumer-oriented evaluation model) were utilized. A survey form was developed by the researcher after reviewing the various tools originated from Boshier, Cross, Gagne and Choi, and distributed to a panel of judges that examined the content validity of the instrument. The sample for the study consisted of 160 female learners from three universities in Seoul and capital area, and the survey form was used to collect data for this study. The SPSS WIN program was used in analyzing the data and a series of statistical tests were conducted including frequency, percentile, t-test, ANOVA, correlation, multiple regression, and factor analysis. The statistical significance level was 0.05. The following conclusion were drawn from this study of female internet education. First, it was evident that female internet learners tend to utilize information from internet, and this can be interpreted as participants' positive attitude, and voluntary participation. Second, educational facilities and services should be improved in the future, because the level of satisfaction was low in these areas compared to curriculum and educational methodology. Third, the participating factors influenced by the level of satisfaction for education of learner characteristics were the 'formation of inter-personal relationship and willingness to change' and the 'needs for education on internet', thus appeared that both social and educational needs influenced the level of satisfaction for education. Fourth, the degree of achievement in learning was higher in the order of 1) attitude 2) function 3) knowledge, thus, attitude change was the most important in achievement of learning. Fifth, the individual background that influenced the level of achievement in learning were age and educational experience. As for the individual level of achievement for learning, the younger and more educated group were more satisfied.

• Korean Journal of Child Education & Care
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• v.18 no.2
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• pp.103-115
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• 2018

Objective: The purpose of this study was to understand the formation of organizational relationship necessary to the correct operation of daycare centers through the relations between mulitpliership of daycare directors, and teachers cooperation and colleague support of childcare teachers. Methods: The subjects in this study were 234 childcare center teachers in Seoul and Gyoungi Province in South Korea. Two different inventories were utilized. Multipliership scale, teacher cooperation scale and colleague support scale were used. As for data analysis, the frequency analysis, exploratory factor analysis, reliability analysis, and correlation analysis were conducted through SPSS 20.0 program. Results: First, the sub-factors of multipliership of daycare center directors such as working joyfully, settling productive discussion, increasing unity of members, and establishing personal value culture in order were the preceding factors having positive effects on the teachers cooperation of childcare teachers. Second, the sub-factors of multipliership of daycare center directors such as settling productive discussion, establishing personal value culture, working joyfully, and increasing unity of members in order were the preceding factors having positive effects on the colleague support of childcare teachers. Conclusion/Implications: This study suggests researches improve the quality of childcare, and also researches on the development of programs enhancing multipliership.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.3
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• pp.22-30
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• 2010

This paper proposes a combination system of Adaptive Modulation and Coding (AMC) and Multiple Input Multiple Output (MIMO), which improves the throughput and has a better reliability. In addition, the system includes Precoding, Antenna Subset Selection and MIMO Mode Selection scheme. Finally, we make a performance analysis of the proposed system. The principal environmental parameters for the simulation experiment consist of a frequency non-selective rayleigh fading channel and a Spreading Factor (SF) of 16. Other parameters may be included in order to fulfill the requirements of the HSDP A Standard. The proposed system has a higher throughput and more reliability than the conventional system, which does not include MIMO Mode Selection scheme, Precoding or Antenna Subset Selection. According to the simulation results, the proposed system reaches the maximum throughput at 8dB, presentlng an improvement of 6dB and twice higher throughput, respect to the conventional system. Specifically, at the point of -6dB, the conventional system reaches 2.5Mbps, while the proposed system reaches 6.4Mbps at the same SNR. Also, at the point of 2dB, each system reaches 7.5Mbps (conventional system) and 15.3Mbps (proposed system), with near twice the difference. According to the results exposed above, we can conclude that the system proposed in this paper has, as the greatest contribution, the improvement of the throughput, especially, the average throughput.