• Nuclear Engineering and Technology
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• v.46 no.2
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• pp.195-206
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• 2014

Heat transfer characteristics in a narrow rectangular channel are experimentally investigated for upward and downward flows. The experimental data obtained are compared with existing data and predictions by many correlations. Based on the observations, there are differences from others: (1) there are no different heat transfer characteristics between upward and downward flows, (2) most of the existing correlations under-estimate heat transfer characteristics, and (3) existing correlations do not predict the high heat transfer in the entrance region for a wide range of Re. In addition, there are a few heat transfer correlations applicable to narrow rectangular channels. Therefore, a new set of correlations is proposed with and without consideration of the entrance region. Without consideration of the entrance region, heat transfer characteristics are expressed as a function of Re and Pr for turbulent flows, and as a function of Gz for laminar flows. The correlation proposed for turbulent and laminar flows has errors of ${\pm}18.25$ and ${\pm}13.62%$, respectively. With consideration of the entrance region, the heat transfer characteristics are expressed as a function of Re, Pr, and $z^*$ for both laminar and turbulent flows. The correlation for turbulent and laminar flows has errors of ${\pm}19.5$ and ${\pm}22.0%$, respectively.

• Journal of Ecology and Environment
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• v.31 no.3
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• pp.183-191
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• 2008

To determine the age structure of a Hynobius leechii breeding population and analyze relationships between the order of entrance to breeding ponds and physical parameters and age, we studied a wild population of the species in the Research Forests of Kangwon National University in Chuncheon, Kangwon, South Korea from March 16 to April 13, 2005. The age of breeding males ranged one to nine years old and that of females ranged from three to nine years old. The asymptotic sizes of males and females were 6.36 and 6.51 cm, respectively, and the growth coefficients of males and females were 0.71 and 0.81, respectively. The snout-vent length (SVL), head length, and body mass of males were all positively correlated with their age, but female age did not show a significant relationship with any physical parameter. The tail depth, body mass, and condition factors (SVL/body mass $\times$ 100) of both males and females were negatively related with the order of entrance to the breeding pond. The head width and SVL of males were also negatively correlated with the order of entrance, but the SVL of females was positively related with the order of entrance. These results suggest that physical parameters are more important determinants of breeding migration patterns than age. We discuss which of two hypotheses, the mate opportunity hypothesis and the susceptibility hypothesis, is better able to explain the order of entrance to breeding ponds for male and female H. leechii.

• Child Health Nursing Research
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• v.11 no.3
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• pp.348-355
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• 2005

Purpose: In order to provide basic information for the development of nursing programs, health promoting behavior of students rewriting college entrance examinations was examined and factors related to health promotion were identified. Method: Data were collected by questionnaire from 804 examines in Seoul and Gyeonggi Province and were analyzed using the SAS program with t-test, ANOVA, Scheffe's test and Pearson correlation coefficients. Result: The mean score for health promoting behavior was 2.50. The highest score for the sub-areas was harmonious relationships and the lowest was, professional health maintenance. There were significant differences in health promoting behavior according to the following general characteristics; religion, frequency of rewriting college entrance examination, economic burden, parents' education level, grade, satisfaction with parents, friends and rewriting of college entrance examinations, parents' health concernsand knowledge of health, need for health education, and health condition and chronic disease over the past year. Correlations between health promoting behavior and family support and self-esteem were positive. The variables that influenced health promoting behavior were family support ($24.5\%$), self-esteem ($11.3\%$), anxiety ($2.6\%$), and stress of studying ($0.5\%$), explaining $38.9\%$ of the total variance. Conclusion: These results will help to develop a nursing program that enhances health promoting behavior of students rewriting college entrance examinations.

• Journal of Korean society of Dental Hygiene
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• v.14 no.1
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• pp.9-15
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• 2014

Objectives : The purpose of the study was to investigate the influencing factors of major and university choice in the changing environments that kick out the insincere universities keeping pace with the national policy. Methods : A self-reported questionnaire was completed by 177 subjects after receiving informed consents. The questionnaire consisted of general characteristics, influencing factors on university and department choice including multiple application. Chi-square test was used for analysis of the difference between early and regular admission. Results : Employment was the most important reason for choice of dental hygiene department that accounted for 96%. The access route for university information was college homepage for entrance information that accounted for 72.3% and 76.3% of applicants were advised by their parents for their choice for university. The information was mainly composed of school life(92.1%) and employment (81.9%). The applicants wanted to meet the students(58.8%) and to come in contact with the university homepage(57.1%). Early and regular applicants differed in reasons for college entrance(p=0.032), information delivery for major(p=0.013) and multiple application for entrance(p<0.01). Conclusions : University homepage and communication with the students will give much information to the applicants. So the university had better choose the homepage and communication for marketing strategy.

• The Korean Journal of Applied Statistics
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• v.23 no.5
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• pp.987-996
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• 2010

The goal of the entrance examination models is to promote promising and potential students who are suitable for post-secondary education purposes. Recently, a promotion system based on the admissions supervisors has been the major role for the promotion of students. Various statistical models and methods should be applied for the better and reasonable promotion of promising Korean and international students. In this study, we applied the proper methods in statistical methodologies and show the meaningful results on the performance evaluation of the several entrance examination models for a university in Seoul, Korea.

• Journal of Educational Research in Mathematics
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• v.26 no.2
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• pp.287-307
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• 2016

In this study, mathematics exams for university entrance in the USA, the UK, Australia, Singapore, and Japan are investigated. We look into SAT, ACT and AP-course in the USA, GCE A-level test in the UK and Singapore, VCE in Australia, and UECE (University Entrance Center Exam) and individual university's admission tests in Japan. Those exams are analyzed in terms of exam system, mathematical contents, types of items, and testing time. Based on the result five issues on university entrance exam system in Korea are drawn out: types of tests, mathematical contents, item types, sub-items, and opening tests results to the public.

• Journal of the Korean Data and Information Science Society
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• v.18 no.1
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• pp.1-10
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• 2007

In this paper, we focus on churn analysis for the first successful candidates in the entrance examination on 2006 year using Clementine, data mining tool. The goal of this study is to apply decision tree including C5.0 and CART algorithms, neural network and logistic regression techniques to predict a successful candidate churn. And we analyze the churning and nochurning successful candidates and why the successful candidates churn and which successful candidates are most likely to churn in the future using data from entrance examination data of K university on 2006 year.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.14 no.3
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• pp.21-28
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• 2018

This paper presents two-step simulations to calculate the influence of blast-induced pressures on explosion-protection valves installed at the boundary between a protection facility and a tunnel entering the facility. The first step is to calculate the respective overpressure on the entrance and exit of the tunnel when an explosion occurs near the tunnel entrance and exit to approach the protection facility. Secondly, the blast pressures on the explosion-protection valves mounted to walls located near the tunnel inside approaching the protection facility are analyzed with a 0.1 ms time variation using the results obtained from the first-step calculations. The following conclusions could be derived as a results: (1) The analysis of the entrance tunnel scenario, P1, leads to the maximum overpressure of 47 kPa, approximately a half of the ambient pressure, at the inner entrance due to the effect of blast barrier. For the scenario, P2, the case not blocked by the barrier, the maximum overpressure is 628 kPa, which is relatively high, namely, 5.2 times the ambient pressure. (2) It is observed that the pressure for the entrance tunnel is effectively mitigated because the initial blast pressures are partially offset from each other according to the geometry of the entrance and a portion of the pressures is discharged to the outside.

• Journal of architectural history
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• v.14 no.4 s.44
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• pp.117-135
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• 2005

This paper is a study of the possibility of experience and expression in the architecture of Louis I. Kahn by focusing on the characters of entrance, court and window/wall of his public buildings. In the course of composition, Kahn defined the entrance, court and window/wall as an connecting elements and elements of boundary. The characters revealed by these elements or rooms give the clue to insight Kahn's thought of relation of interior and exterior space or inner and outer space. Following are the characters of these elements. First, a entrance reveals the fact that inner space separates from outer space by connecting these two space and giving the value to inner space as the entity and totality like outer space. The entrance gives its ontological being to human subjects not by vision but experience and expression which is the essence of commonness, that is, Silence. Kahn made the possibility of activity amplify in this common and silent space. Second, this entrance is connected with wide and huge central space not individual spaces of interior space. This extreme procedure of entering makes human subject feel sublime of intoner space. And the central spaces becomes another exterior or another world in the inner world of architecture by the lights from above and by having the boundary wall which shows same pattern of exterior wall. Third, Kahn regarded a window as the giver of lights not as the medium of vision connecting inner space with outer. He tried to connect interior with exterior through the being and character of the light expressed in the interior. And in his buildings, interior space is connected with exterior by expressing the purpose of building, composition of inner space, structural truth and construction facts through the Form, a pattern of wall, details and ornamental joints. By practicing this thoughts in the real buildings, Kahn tried to gave aura to both the interior space and entity of architecture which is regarded as micro universe like flowers, rocks and human beings.

• Journal of Radiation Protection and Research
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• v.42 no.2
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• pp.77-82
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• 2017

Background: This study aims to predict the midline dose based on the entrance and exit doses from optically stimulated luminescence detector (OSLD) measurements for total body irradiation (TBI). Materials and Methods: For TBI treatment, beam data sets were measured for 6 MV and 15 MV beams. To evaluate the tissue lateral effect of various thicknesses, the midline dose and peak dose were measured using a solid water phantom (SWP) and ion chamber. The entrance and exit doses were measured using OSLDs. OSLDs were attached onto the central beam axis at the entrance and exit surfaces of the phantom. The predicted midline dose was evaluated as the sum of the entrance and exit doses by OSLD measurement. The ratio of the entrance dose to the exit dose was evaluated at various thicknesses. Results and Discussion: The ratio of the peak dose to the midline dose was 1.12 for a 30 cm thick SWP at both energies. When the patient thickness is greater than 30 cm, the 15 MV should be used to ensure dose homogeneity. The ratio of the entrance dose to the exit dose was less than 1.0 for thicknesses of less than 30 cm and 40 cm at 6 MV and 15 MV, respectively. Therefore, the predicted midline dose can be underestimated for thinner body. At 15 MV, the ratios were approximately 1.06 for a thickness of 50 cm. In cases where adult patients are treated with the 15 MV photon beam, it is possible for the predicted midline dose to be overestimated for parts of the body with a thickness of 50 cm or greater. Conclusion: The predicted midline dose and OSLD-measured midline dose depend on the phantom thickness. For in-vivo dosimetry of TBI, the measurement dose should be corrected in order to accurately predict the midline dose.