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Development of a Prototype for the Digitalized Nuclear Power Plant's Main Control Room (원자력발전소 디지털형 주제어실 모형 개발)

  • Jung, Yeon-Sub;Cho, Sung-Jae
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.9 no.4
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    • pp.145-152
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    • 2009
  • Domestic Kori-1 MCR was partially modified in 2007 and will be renovated entirely in 2013. Digital devices partially replacing original analog devices have been introduced and standard alone computer systems such as SPDS have been integrated into the plant computer. Upgrading KSNP's MCR based on the ditalization is planned for 2015. However, the site engineers and operators are reluctant to the advanced systems. Therefore, a prototype for the KSNP's advanced MCR has been developed to increase the acceptance level of the operators and field engineers and also, to evaluate user interfaces and I&C architecture. For enhancing support of the operators' work, a P&ID based display system composed of multi-layers, which are linked through a context sensitive menu each other, has been adopted. The $1^{st}$ layer displays a simplified P&ID, the $2^{nd}$ layer control related diagrams such as controllers and logic diagrams, the $3^{rd}$ layer trends, etc. The end point view of MCR for KSNP is also suggested considering reliability and operability of the digital systems. Additionally, modernization strategies over the overhaul periods, that do not have much impact on operation and configuration efforts are suggested.

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Partial Safety Factors for Geotechnical Bearing Capacity of Port Structures (항만구조물 지반지지력 산정을 위한 부분안전계수 결정)

  • Yoon, Gil-Lim;Yoon, Yeo-Won;Kim, Hong-Yeon;Kim, Baeck-Oon
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.22 no.3
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    • pp.156-162
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    • 2010
  • When eccentric or inclined load acts on foundation of the port & harbor structures, partial safety factors of bearing capacity limit state were estimated using reliability analysis. Current Korean technical standards of port and harbor structures recommend to estimate the geotechnical bearing capacity using the simplified Bishop method. In practice, however, simple method of comparing ground reaction resistance with allowable bearing capacity has been mostly used by design engineers. While the simple method gives just one number fixed but somewhat convenient, it could not consider the uncertainty of soil properties depending on site by site. Thus, in this paper, partial safety factors for each design variable were determined so that designers do perform reliability-based level 1 design for bearing capacity limit state. For these, reliability index and their sensitivities were gained throughout the first order reliability method(FORM), and the variability of the random variables was also considered. In order to verify partial safety factors determined here, a comparison with foreign design codes was carried out and were found to be reasonable in practical design.

Comparison between Numerical Results of 1D Beam and 2D Plane Stress Finite Element Analyses Considering Aspect Ratio of Cantilever Beams (캔틸레버보의 형상비에 따른 1차원 보와 2차원 평면응력 유한요소해석 결과의 비교)

  • Kang, Yoo-Jin;Sim, Ji-Soo;Cho, Hae-Sung;Shin, Sang-Joon
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.28 no.5
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    • pp.459-465
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    • 2015
  • There exist different kinds of aircrafts, such as conventional airplane, rotorcraft, fighter, and unmanned aerial vehicle. Their shape and feature are dependent upon their own assigned mission. One of the fundamental analyses performed during the aircraft design is the structural analysis. It becomes more complicated and requires severe computations because of the recent complex trends in aircraft structure. In order for efficiency in the structural analysis, a simplified approach, such as equivalent beam or plate model, is preferred. However, it is not clear which analysis will be appropriate to analyze the realistic configuration, such as an aircraft wing, i.e., between an equivalent beam and plate analysis. It is necessary to assess the limitation for both the one-dimensional beam analysis and the two-dimensional plate theory. Thus, in this paper, the static structural analysis results obtained by EDISON solvers were compared with the three-dimensional results obtained from MSC NASTRAN. Before that, EDISON program was verified by comparing the results with those from MSC NASTRAN program and other analytic solutions.

Impacts of Core Elements of ISO26000 using Quantile Regression Analysis on Organizational Trust of Casino Industry (분위수 회귀분석을 이용한 ISO26000의 핵심요소가 카지노기업의 조직신뢰에 미치는 영향)

  • Lee, Hwa-Yong;Kim, Sang-Hyuck
    • Management & Information Systems Review
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    • v.32 no.1
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    • pp.173-194
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    • 2013
  • The purpose of this study drew the core elements of ISO26000 by analyzing the elements suitable to the characteristics of casino companies, and examined the influence of the core elements of ISO26000 on organizational trust following the level of organizational trust of employees. As a result of the factor analysis, among the 7 measurement items of ISO26000, improvement of governance and fair operating practices were simplified into one factor and thus 6 factors were used for empirical analysis. Therefore, multiple regression analysis using least square method was conducted to examine the impacts of the 6 elements. As a result, 5 variables excluding human rights had significant impacts on the organizational trust. Concretely, the 5 core elements of ISO26000 (labor practices, governance and fair operation, consumer issues, environment and community social and economic development) had significant impact on organization trust in order. In addition, the results of quantile regression analysis show the core elements of ISO26000 had different impacts on organizational trust depending on the level of organizational trust of employees.

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Dimensional Changes of Ceromer Crown by Water Absorption (치과용 심미수복재료 세로모에서 수분흡수와 체적 변화에 관한 연구)

  • Lee, Jong-Hyuk
    • The Journal of Korean Academy of Prosthodontics
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    • v.47 no.2
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    • pp.119-124
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    • 2009
  • Statement of problem: The increasing demand for esthetic restorations has been required developing new materials for tooth colored restoration. Ceromer(Ceramic Optimized Polymer) has some advantages over porcelain, and has gained increasing popularity in restorative dentistry. However, there is little information on the dimensional changes in a clinical restoration in moist conditions. Purpose: This study examined the dimensional changes in Ceromer restorations with a clinical crown shape that were fabricated in a clinical manner. Material and methods: The crowns for the maxillary central incisor were fabricated with two Ceromers($BelleGlass^{(R)}$ and $Targis^{(R)}$) using a similar clinical restoration manufacturing technique. A total of twenty specimens were prepared and immersed in distilled water at room temperature to allow for water absorption. The weight, height and width were measured at 24, 72 and 168 hours. The accumulated ratios of the changes were calculated and evaluated using a paired t-test and an independent independent t-test. Results: The dimensions and weight increased with increasing soaking time. $Targis^{(R)}$ showed significant differences in height and weight between 24 hours and the other times(P<.05). $BelleGlass^{(R)}$ showed significant differences in width and weight between 24 hours and the other times. The two materials showed different changing patterns of the dimensions but there were no statistically significant differences between them. Conclusion: The dimensions and weight of the Ceromer restorations were changed by water absorption. The clinical crown shaped specimen showed more complicated dimensional changes than the simplified specimens.

The Effects of Small-group Discussion Lesson Using Concept Sketches in Astronomy of Earth Science (지구과학 천문 영역에서 개념스케치를 활용한 소집단 토론 수업의 효과)

  • Kim, Youn-Gui;Jeong, Gu-Song
    • Journal of The Korean Association For Science Education
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    • v.30 no.1
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    • pp.170-180
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    • 2010
  • Among the various fields of Earth Science, especially in Astronomy, we often deal with the change of space-time in an abstract way. Thus, making use of 'Concept Sketches'-simplified sketches that represent the main features, principles, processes and interrelationships of the learning content by using some concise explanations, signs and terms could help the students efficiently learn the phenomena of Astronomy. This study's aim was to check its effects and analyze the results of the lessons that included concept sketches and a discussion about the field of Earth Science in high school. The control group took traditional lessons, while the experimental group did a small-group discussion that used the concept sketches. After the lesson, some students were chosen to answer a questionnaire and go through an in-depth interview. The result of the data shows that the small-group discussion lesson that used the concept sketches helped both the high-ranking and low-ranking students to build concepts and was able to attract students' attention. Moreover, the students produced long-term memories of the content learned through the class discussion, which allowed them to exchange their own thoughts and opinions with other students. Most of all, drawing pictures, a familiar activity, appealed to the students, so they took part in the class eagerly.

Clothing Culture and Korean Women (복식문화와 여성)

  • 임숙자
    • The Research Journal of the Costume Culture
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    • v.4 no.2
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    • pp.113-124
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    • 1996
  • This research was designed to find out what is a distictive feature of the design elements of Korean women's costume and its influence by analizing the trend of Korean women's constume during the period of 1890 and 1995. The research was analized by a total of 854 random samples of clothing styles collected from materials in the museums and from articles of three leading newspapers and one of the best women's magazines in Korea. The changing trend of Korean women's costume was found out to be as follows: 1. In around 1910s, the trend of Korean women's costume has been changed into two-tier structure of both Korean and Western styles, and the typical and traditional Korean women's street wears such as 'Chang-ot' and 'Tsdechima' have been gradually diminished. 2. From 1920s, length of the Korean skirt, which was unnecessarily long and inconvenient, has been getting shorter for the convenience of walking. In addition, Korean women's underwear has become simplified, and sports wear could be seen for the first time in Korea. 3. During 1960s, the Western clothing styles have been increased rather than Korean styles as the street wear of the Korean women. 4. In 1970s, blue jeans, mini-skirts and casual wears have become a trend or fashion for women in Korea. 5. In 1980s, a fashion of unisex mode has arrived in this country, and from the year of 1987, wearing of panties among the Korean women has been increased rather than skirts wearing for the street wear. 6. During 1990s, various forma of complex styles came into being in such styles as so-called 'orange class style,' 'protruding navel T-shirts' and 'runner wear speedy.' From mid-1990s, Korean women have turned out to prefer the cute and light costumes by placing emphasis on the image of intellectual, professional and functional wears. The changing special feature of the Korean women's clothing designs could be distinctively observed during 1960s as the modernization policies in Korea have been processed during the period. The clothing trend before 1960 was to change and to solve problems of inconvenient and impractical wears, but the trend after 1960 was seen as a change to confirm a trend of the world fashion. From mid-1990s, however, preference of Korean women's self-conceited conception socially and an unquestionable changing pattern of Korean women's life.

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Contraction of Alpha-nickel Hydroxide Layers by Excess Coulombic Attraction of Anions (전기화학적으로 형성된 알파 상 니켈 수산화물의 층간 거리에 미치는 음이온의 영향 연구)

  • Kim, Gwang-Beom;Ganesh Kumar, V.;Bae, Sang-Won;Lee, Jae-Seong
    • Journal of the Korean Chemical Society
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    • v.50 no.2
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    • pp.141-152
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    • 2006
  • In this study computer assisted instruction materials for the ‘Solution' chapter in high school chemistry II textbook were developed based on a view of particle and analyze the effect of the materials on 10th and 11th high school students. The contents of developed materials are dissolution, vapor pressure, the change of boiling point and freezing point, osmosis, and so on which are the major contents of Solution chapter in high school chemistry II textbook. Materials were developed with using animation and simulation for students understanding of the phenomena with a particle view point. Many phenomena in a solution were not simplified by colligative property of solution, but tried to explain by the concept of attraction between solute and solvent molecules. This computer assisted learning materials were developed using Flash 5.0 and Flash 6.0 Action Script. Educational effects of the materials on 10th and 11th grade students represented statistically meaningful increase of concept understanding. Especially the materials were effective to the transition stage or formal stage students in 10th grade and formal stage or the natural science major students in 11th grade.

Measurement of Velocity-Lag of Suspended-Sediment Particles in Turbulent Open-Channel Flows (난류 중 부유사의 속도 지체 측정)

  • Yu, Kwon-Kyu;Marian Muste;Robert Ettema;Yoon, Byung-Man
    • Journal of Korea Water Resources Association
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    • v.39 no.2 s.163
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    • pp.99-108
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    • 2006
  • To describe the behavior of suspended-sediment particles in turbulent open-channel flows, the advection-diffusion equation or its simplified form has been used. Though this equation was derived upon several assumptions, only a few studies tried to evaluate the limit of the assumptions. The reason is that it is very difficult to measure turbulence in open-channel flows and to discriminate the velocities of water and sediment particles. The present study aims to measure the velocity profiles of water and sediment particles in open-channel flows by using PTV (Particle Tracking Velocimetry), a kind of PIV (Particle Image Velocimetry). The measured results showed that sediment particles moved slower than water tracers did in the outer region. In the present study, the amount of velocity-lag reached about $5\%$ of the mom flow velocity and the position of the maximum velocity-lag was $g/h\approx0.05\;(g^{+}=30\~50)$ The main cause of the velocity-lag of sediment particles seems that the sediment particles have larger density than water has. On the other hand, in the viscous sublayer, sediment particle has a larger velocity than water tracers. The reason of the inversion of velocity-lag may be due to the no-sleep condition of water at the solid boundaries.

FFC2Q Model for NPS Load Analysis according to Characteristics of Early Stage of Runoff (강우 초기특성에 따른 비점오염부하량 산정을 위한 FFC2Q 모형)

  • Lee, Jong-Tae;Seo, Kyung-A;Hur, Sung-Chul
    • Journal of Korea Water Resources Association
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    • v.43 no.3
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    • pp.245-256
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    • 2010
  • We study the basic theory and applicability of the WQUAL block in the FFC2Q model and the characteristics of non-point pollutant loads during the early stage of runoff. Study is also performed on selection of the values of the related parameters and their effect on the simulation results. FFC2Q simulation results are compared for verification with the measured data for three rainfall events in the Gunja Subbasin and found to be similar to the measured data in peak-flows, total runoff volumes, total loads, peak concentrations and times of peak concentration. This model thus shows results very close to those applying the SWMM and MOUSE models, even though it uses simplified input data. Related to rainfall distribution, under the condition of Huff 1st quartile distribution the pollutant loads occurred earlier than under other conditions, and in the early stage of rainfall the BOD and COD loads increased faster than the SS loads. The NPS loads were concentrated in the early stage of rainfall and finally reached total loads, so the rainfall after that could not contribute so much to the NPS loads.