• Title/Summary/Keyword: Nuclear structure

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Mock-up Test for Nuclear Power Plant Rebar Modulation Applying Febrication (선조립공법을 활용한 원전구조물 철근모듈화 Mock-up 실험연구)

  • Lim, Sang-Jun;Lee, Byung-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2015.05a
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    • pp.13-14
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    • 2015
  • To minimize construction of nuclear facility, it is required to reduce reinforcing bar amount and solve reinforcing bar concentration and for this, it is necessary to develop appication design technology and modular of high strength reinforcing bar. Hence, KHNP reduces excessive reinforcing bar amount which can cause possibility of poor construction of concrete through design standard development and modular of nuclear facility structure using high strength reinforcing bar to raise economics and has its purpose to maintain high-level safety and durability as they are. After reviewing the rebar drawing of the NPP structures and performing the mock-up test, the rebar modulation method in the various area of the NPP Structure has been established.

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Effect of octadecylamine concentration on adsorption on carbon steel surface

  • Liu, Canshuai;Lin, Genxian;Sun, Yun;Lu, Jundong;Fang, Jun;Yu, Chun;Chi, Lisheng;Sun, Ke
    • Nuclear Engineering and Technology
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    • v.52 no.10
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    • pp.2394-2401
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    • 2020
  • Octadecylamine is an effective film-forming amine that protects carbon steel from corrosion. In the present study, the effect of octadecylamine concentration on adsorption on a carbon steel surface was investigated in anaerobic alkaline solution by using SEM/EDS, TEM and the Materials Studio simulation techniques. TEM morphology observation and EDS elemental detection determine the thicknesses of octadecylamine film on a carbon steel surface, which are confirmed by the in-situ electrochemical impedance spectroscopy measurement and resistance calculation. The Materials Studio simulation reveals the number of octadecylamine film layers at different concentrations. Results obtained in this study indicate that adsorption of octadecylamine film on carbon steel proceeds with the multi-layer adsorption mechanism.

ASSESSMENT OF PROPERTIES AND DURABILITY OF FLY ASH CONCRETE USED IN KOREAN NUCLEAR POWER PLANTS

  • Cho, Myung-Sug;Noh, Jae-Myoung
    • Nuclear Engineering and Technology
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    • v.44 no.3
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    • pp.331-342
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    • 2012
  • Since the opening of the Shin-Kori #1,2 in 2005, fly ash mixed concrete has been used for NPP concrete structures under construction in Korea with the aim of preventing aging and improving durability. In this paper, the quality suitability of fly ash manufactured in Korea is assessed and the basic physical properties of fly ash mixed concrete and its durability against primary causes of aging are verified through experimental methods. Because of the internal structure filling effect from the pozzolanic reaction of fly ash and the resulting improvements in mechanical performance in such areas as strength and salt damage resistance, the durability of fly ash mixed concrete is shown to be superior. It is judged that this result can be applied in measures not only for improving the safety of NPP structures in operation in Korea but also for implementing effective structure life management should extending the life of structures be needed in the future.

Sperm nuclear DNA fragmentation and chromatin structure in one-day-old ejaculated sperm

  • Jee, Byung-Chul;Suh, Chang-Suk;Shin, Mi-Sun;Lee, Hee-Jun;Lee, Jae-Ho;Kim, Seok-Hyun
    • Clinical and Experimental Reproductive Medicine
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    • v.38 no.2
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    • pp.82-86
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    • 2011
  • Objective: To evaluate sperm nuclear DNA fragmentation and chromatin structure after 18 hours' incubation at room temperature. Methods: Twenty-eight male partners who participating IVF treatment were prospectively included in this study. Ejaculated sperm count and motility were assessed. The sperm was then immediately processed by the conventional swim-up method. After utilization of some of the sample for routine clinical use, the remainder of each of the samples was divided into two aliquots. One aliquot was immediately assessed for sperm nuclear DNA fragmentation (TUNEL assay) and chromatin structure (toluidine blue [TB] staining). The other aliquot was incubated at room temperature for 18 hours and then assessed by two methods. Only dark-TB sperms were considered as having abnormal chromatin structure. Data before and after extended incubation were compared using a paired Student's $t$-test. Results: Before and after extended culture, nuclear DNA fragmentation assessed by TUNEL was $4.9{\pm}4.7%$ and $7.0{\pm}6.4%$, respectively ($p$=0.008). The proportion of abnormal chromatin structure (dark-TB sperm) was $8.2{\pm}5.6%$ and $10.3{\pm}6.5%$ ($p$ <0.001), before and after incubation, respectively. Conclusion: After 18 hours' incubation at room temperature, sperm nuclear DNA and chromatin structure were significantly affected. The IVF practitioner should bear this information in mind when performing delayed insemination, especially for $in$ $vitro$ maturation cycles.

Performance Analysis of the Mid-Level Communication Network for DCS in NPP (원자력 발전소 분산제어 시스템을 위한 중위 계층 통신망의 성능 분석)

  • Lee, Sung-Woo;Yim, Han-Suck
    • Proceedings of the KIEE Conference
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    • 1998.07b
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    • pp.816-818
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    • 1998
  • In this paper, a highly reliable communication network for DCS (Distributed Control System) in nuclear power plant is designed. The structure and characteristics of DCS in nuclear power plant is briefly explained. The features needed for a communication network for DCS in nuclear power plant is described. According to the above features, a layer structure for the communication network is determined and each layer is designed in detail. Accuracy of the model was evaluated by computer simulation.

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