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UNCERTAINTY EVALUATIONS OF CASMO-3/MASTER SYSTEM FOR PWR CORE NEUTRONICS CALCULATIONS

  • Song, Jae-Seung;Kim, Kang-Seog;Lee, Kibog;Park, Jin-Ha;Zee, Sung-Quun
    • Proceedings of the Korean Nuclear Society Conference
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    • 1996.05a
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    • pp.244-250
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    • 1996
  • Uncertainties in core neutronic calculations of CASMO-3/MASTER, which is a KAERI developed core nuclear design code system, were evaluated via comparisons with measured data. Comparisons were performed with plant measurement data from one Westinghouse type and one ABB-CE type plant and two Korean standard type plants. The CASMO-3/MASTER capability and levels of accuracy are concluded to be sufficient for the neutronics design including safety related parameters related with reactivity, power distributions, temperature and power coefficients, inverse boron worth and control bank worth.

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A Longitudinal Study on the Effect of the Application Usage Period on the Change of Digital Shadow Work Type: Focused on LBS-based Help Apps Service (애플리케이션 사용자의 사용기간이 디지털그림자노동의 유형 변화에 미치는 영향에 대한 종단 연구: LBS 기반 도와줘 앱 서비스를 중심으로)

  • Jung-Sik, Song;Woong-Kyu, Lee;Byeong Hoon, Lee;Joon, Koh
    • Journal of Information Technology Services
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    • v.21 no.6
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    • pp.91-116
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    • 2022
  • This research shows how the perception of digital shadow work varies depending on the user's period of use of digital services in applications, which are key areas of digital services. The purpose of this research is to investigate how the digital shadow work type changes over time. This research adopted a qualitative research method for location-based service "help application" users and examined the change in perception from the app service acceptance stage to the app service continuous use stage with two-times interviews of ten users by a longitudinal research design. This study conducted a longitudinal analysis focusing on how digital shadow work occurs in the application subscription process, exploring phenomenologically how the type changes throughout the process over time.

Experimental Evaluation for Hydrodynamic Performance of a Hybrid Supported Type Fast Craft

  • Yang, S.I.;Koh, C.D.;Ahn, J.W.;Kim, Y.G.;Lee, J.-T.
    • Journal of Ship and Ocean Technology
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    • v.4 no.4
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    • pp.34-44
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    • 2000
  • This paper deals with the sea trial results of a fast craft with the hybrid supported type hul form. waterjet propulsion system and motion control system. The hybrid-type container ship operable in the sea with a wave height of y6 m, a speed of 50 knots and a payload of 1,500 tons were designed. A 1/8 scale 10 m- long test craft was constructed and tested in open seas. The hydrodynamic performance such as speed, turning, motion control in waves and waterjet thrush was analyzed.

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The Actual Wearing Conditions and Preferences for New Silver Women's Brassiere (뉴실버 여성을 위한 브래지어 착용실태 및 선호도 조사)

  • Park, Ja Young;Jang, Jeong Ah
    • Fashion & Textile Research Journal
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    • v.16 no.4
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    • pp.635-644
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    • 2014
  • This study provides basic reference data for brassiere wearing conditions, design preferences of new silver women (50s-60s) and development of brassiere products. We compiled and compared 163 pieces of brassiere (considering of 105 domestic general brassieres and 58 foreign silver brassieres) analyzed using SPSS Statistics 21 program. A survey was then conducted on the actual wearing, purchasing conditions, design preferences for 176 females (50s-60s). The result of this study are as follows: First, comparing actual product conditions (domestic general products and foreign silver products), the ratio of full cup in cup height, V-shape type in neckline shape, long type in front-end length, wide type in wing width, U-shape type in shoulder strap form, wide type in shoulder strap width, no-wire brassieres in breast wire type, all-in-one type in shoulder strap separation, back type in closure type appeared higher than other types of brassiere in domestic general product. Second, a study also showed that 60s women's wearing time is lower than 50s women's; however, 60s women expressed a higher figure and preference for the purchasing ratio in the department store, full cup in cup height, short type in length of brassieres, wide type in wing width, U-shape in shoulder strap form, small type in shoulder strap width, back type in closure type and no-wire brassieres than those in their 50s. It was found they prefer fabric with a high natural content, nude tone color without decoration & pattern and camisole brassieres.

Heat flow Analysis of Heat Sink Using the Computational Simulation (전산모사를 이용한 히트싱크의 열 유동 해석)

  • Lim Song Chul;Chang Si Young;Kim Hyon Tae;Lee Dong Heon;Kang Kae Myung
    • Korean Journal of Materials Research
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    • v.14 no.7
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    • pp.522-528
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    • 2004
  • Heat analysis of the plate type and wave type heat sink were carried out by using computational simulation. The heat resistance and air flow of two heat sink models were analysed according to natural and forced convection condition and positions of fan. When a fan was at the position of z-axis and y-axis in forced convection, the heat resistances of plate type heat sink were $0.17^{\circ}C/W$, and $0.28^{\circ}C/W$ respectively. In the case of wave type heat sink, they were $0.18^{\circ}C/W$ and $0.53^{\circ}C/W$. As the air flow velocities were averagely $0.386\;m/s\~3.269\;m/s$, air flow velocity of plate type heat sink was faster than that of wave type. In this experiment, it was observed that the plate type heat sink showed a good ability of heat radiation comparing with wave type one.

The analysis of temperature and light intensity characteristics of PV modules with solar cell type (Cell-Type에 따른 PV모듈의 일사강도와 온도 특성 비교)

  • Bae, Jong-Guk;Kim, Kyung-Soo;Kang, Gi-Hwan;Yu, Gwon-Jong;Ahn, Hyung-Gun;Han, Deuk-Young
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.1316-1317
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    • 2011
  • This paper presents analysis of temperature and light intensity characteristics of PV modules with solar cell type. Taking the effect of sunlight irradiance on the cell temperature, the first experiment takes ambient temperature as reference input and uses the solar insolation as a unique varying parameter. Then taking the effect of the cell temperature on sunlight irradiance, the second experiment takes 1000W/$m^2$ as reference input and uses the cell temperature as a unique varying parameter. As a result, varying sunlight irradiance, the Cell-Type with the smallest change in output is HIT and the Cell-Type with the biggest change in output is a-Si. Varying the cell temperature, the Cell-Type with the smallest change in output is a-Si and the Cell-Type with the biggest change in output is Single-Si. And considering both temperature and light intensity characteristics, the Cell-Type with the smallest change in output is HIT.

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A Study on the Design of Men's Jacket Pattern (남성 재킷 패턴 설계에 관한 연구)

  • Lee Won-Ja;Kim Jin-Sun
    • The Research Journal of the Costume Culture
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    • v.12 no.6 s.53
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    • pp.953-970
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    • 2004
  • The purpose of this study was to design men's jacket pattern for variable body types by employing the data of wearing evaluation from experimental basic bodices selected by male subjects in the 30's. As a result of sensory evaluation, functional test and clothing pressure test by each type of experimental basic bodices, the 3rd experimental basic bodice was chosen to be a basic bodice type in this research since it showed a high degree in fitness and function, but a low in the clothing pressure test. As a comparison of one item from conventional jacket and sleeve pattern with each somatotype, the type 2(the standard somatotype) indicated a great fitness in both basic bodice type and conventional jacket pattern, whereas the type 1 and the type 3 showed higher fitness and moving function in the basic bodice type. In the making of men's jacket, many corrections were made in the front interscye breadth, back interscye breadth, front and back length, and shoulder line as adapting each body type. Thus, the ease-amount of chest circumference at scye for clothes should be established differently according to the size of chest circumference at scye.

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Short-circuit Analysis of Solenoid and Pancake Type Bifilar Winding Magnets using BSCCO tape

  • Park Dong Keun;Ahn Min Cheol;Yang Seong Eun;Yoon Il Gu;Kim Young Jae;Ko Tae Kuk
    • Progress in Superconductivity and Cryogenics
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    • v.7 no.4
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    • pp.28-31
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    • 2005
  • To verify the feasibility of bifilar winding type superconducting fault current limiter (SFCL) using BSCCO tape, two types of magnets were fabricated and tested by short-circuit in this research. Even if the FCL using high Tc superconducting (HTS) tape has zero resistance in normal state, it needs to be wound as a bifilar winding for zero inductance. Solenoid type and pancake type bifilar winding magnets are designed and fabricated with the same length of BSCCO tape. The test system consists of AC power supply, transformer, fault switch, load and bifilar winding magnet. The applied AC voltages during fault duration, 0.1s, were from 0.5V to 20V. The test results without bifilar winding magnet were compared with those with each type magnets. The test results include voltage against magnet, transport current and generated resistance curve. Thermal stability, the recovery time, was studied from the results of two type magnets. The pancake type was the most effective to limit fault current but the solenoid type was thermally the most stable. From this research, short-circuit characteristics of the two types were obtained.

A Typology of Early Elderly Over 55 Years Using The Korean Time Use Survey from 2009 (중.고령자의 생활시간 유형화 연구)

  • Chae, Hwa-Young;Kim, Joo-Hee;Lee, Ki-Young
    • Journal of Family Resource Management and Policy Review
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    • v.15 no.2
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    • pp.129-146
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    • 2011
  • This study is daily life research which aims to explore people's daily lives using a time dairy survey. The purpose of this study is to develop a typology of early, elderly over 55-year-olds using the 2009 Korean Time Use Survey. The results suggest that each man and woman can be classified according to three dimensions which are work time, housework time, and leisure time. Four groups of men are described: the work and leisure balanced type, the work-oriented type, the leisure-oriented type, and the leisure with housework type. Four groups of women are illustrated: the work-oriented type, the leisure-oriented type, the housework-oriented type, and the passive type. The eight groups are characterized by age, education, income, spouse, gender role, lack of time, and satisfaction of time use.

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n-type ZnO 위 수직 성장된 p-type ZnO 나노와이어 구조의 동종접합 다이오드

  • Hwang, Seong-Hwan;Lee, Sang-Hun;Mun, Gyeong-Ju;Lee, Tae-Il;Myeong, Jae-Min
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2012.05a
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    • pp.87.1-87.1
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    • 2012
  • 넓은 밴드갭 (3.37eV)과 높은 엑시톤 결합에너지 (60meV)를 가지는 ZnO 물질은 ultra violet light 센서 및 light emitting diode (LED)의 재료로써 많은 연구가 진행되고 있다. 특히 나노와이어 구조를 이용하여 소자를 만들 경우 양자효과와 1차원적 캐리어 수송경로 효과로 인하여 그 특성을 보다 향상 시킬 수 있다. 나노와이어를 이용한 이종접합 p-n 다이오드를 제작하기 위하여 ZnO와 격자상수가 비슷한 GaN, NiO, CoO와 같은 물질들이 나노구조 접합에 많이 쓰이고 있지만, 격자상수 차이로 인해서 접합부분 캐리어 수송효율이 떨어지는 단점을 가지고 있다. n-type과 p-type ZnO를 만들어 동종 접합을 만들 경우 이러한 문제점을 극복할 수 있지만, 도핑되지 않은 ZnO가 n-type을 특성을 나타내기 때문에 안정적인 p-type ZnO 합성에 대한 연구가 필수적이다. 본 연구에서는 안정적인 p-type ZnO 합성을 위해서 수열합성법을 이용하여 phosphorus (P) 도핑을 하였고, 나노와이어 diode 구조를 만들었다. P 도핑으로 인한 격자상수 변화는 x-ray diffraction (XRD)를 사용하여 확인하였고, x-ray photoelectron spectroscopy (XPS)를 통해 도핑 원소를 분석하였으며, 이때의 recification ratio, turn-on voltage 등의 전기적 특성을 평가하였다.

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