• 제목/요약/키워드: end cap

검색결과 94건 처리시간 0.025초

Engineering Technology Far-end Telecontrol Cathodic Protection on the Structure of Jetty Bridge Cap Beams

  • Liu, Yi-Hsiung;Lim, Pau-Yee;Shih, Chien-Chis
    • Corrosion Science and Technology
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    • 제2권1호
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    • pp.47-52
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    • 2003
  • 23 cap beams on the 1 Km length jetty bridge in Shin-da power plant (Taipower co., Taiwan) utilize far-end telecontrol cathodic protection technology which is the first case ever used in Taiwan. The system comprises cathodic protection system and te1econtrol monitoring system. The control and monitoring such as protection current adjustment, protection potential and depolarization measurement of the 23 cap beams can be adjusted through system telecontrol operations. Thereby allows monitoring and control of the 23 anode zones in a convenient and cost effective way. This system is at present still in its best running condition since Sept. 1997 when it was completed. All the 23 cap beams can achieve the 100 mV depolarization potential criteria of protection. It meet the specifications of reinforced concrete cathodic protection standard and proved to be very excellent.

중수로 핵연료 봉단마개의 저항업셋 용접을 위한 용접변수 (An Investigation of Welding Variables on Resistance Upset Welding for End Capping of HWR Fuel Elements)

  • 이정원;박춘호;고진현;정성훈;정문규
    • Journal of Welding and Joining
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    • 제7권2호
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    • pp.60-69
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    • 1989
  • The present study was aimed at investigating the effect of welding parameters such as welding current, electrode force(or squeeze force) and parts cleaning on the sound weld, and establishing the most reliable weld conditions for HWP(Heavy Water Reactor) fuel end capping with the resistance upset butt welding. Major results obtained are as follows. 1. The amount of sound weld was increased with increasing weld current(5.0-11KA) because the activated diffusion with increasing heat generation played an important role in eliminating the porosity and weld line in the weld interface. 2. It was found that weld current was not significantly influenced by the electrode force although the increase of it caused a slight increase of weld current and upset deformation. 3. Acetone rinsing before drying for the Zircaloy-4 end cap cleaning produced the reliable sound weld because it would remove the remaining solvent and surface films, and provided the uniform contact between the end cap and the tube. 4. The optimum welding conditions for fuel end capping by a resistance upset hytt welding are obtained as follows. weld current: 10-11KA, electrode force: 62-90KPa parts cleaning: vapor degreasing.rarw.water, acetone rinsing.rarw.drying.

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Penelope Simulation에 의한 불감층 두께 효과 및 HPGe 검출기 분석 (Analysis of the Dead Layer Thickness effect and HPGe Detector by Penelope Simulation)

  • 장은성;이효영
    • 한국방사선학회논문지
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    • 제12권7호
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    • pp.801-806
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    • 2018
  • 게르마늄 결정은 검출에 유용하지 않지만, 광자를 강하게 약화하기 때문에 효율성 저하를 일어키는 불감층을 가지고 있다. 따라서 제조업체가 제공하는 데이터를 검출기 시뮬레이션 모델에 사용하면 계산된 효율성과 측정된 효율성 사이에 약간의 큰 차이가 나타난다. 고순도 게르마늄(HPGe) 검출기의 모양과 치수는 CT 스캔을 통해 몬테카롤롤 시뮬레이션을 위해 형상을 정확하게 형상화하였다. 이 결과 불감층 두께 증가가 효율 감소과정에 미치는 영향을 연구하고자 한다. 불감층의 조정은 50 - 1500 keV의 에너지 범위에서 측정 효율과 시뮬레이션 효율 사이의 ${\pm}3%$의 상대편차와 함께 좋은 일치임을 확인하였다. 불감층 두께에 변화를 주어 시뮬레이션 데이터를 비교하였다. 몬테카롤로 시뮬레이션 결과를 실험 결과와 비교하여 새로운 불감층 두꼐를 얻었다. 1.4와 1.6 mm 두께의 End Cap 시뮬레이션 모델에서 1.5mm 두께의 End Cap시뮬레이션 모델에 대한 불감층 두꼐 결과의 차이는 End Cap 치수의 정확성으로 인한 체계적인 오류였다. 통계적 오류와 체계적 오류를 고려한 후, 검출기의 불감충 두께는 $1.02{\pm}0.14mm$로 도출되었다. 따라서 불감층 두께의 증가는 효율성 감소에 영향을 미치는 것을 확인하였다.

Semi-rigidity of cap plate and extended end plate connections

  • Nassani, Dia Eddin;Chikho, Abdul Hakim;Akgonen, Aliriza llker
    • Steel and Composite Structures
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    • 제23권5호
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    • pp.493-499
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    • 2017
  • The behaviour of steel frames is highly influenced by the beam-column connections. Traditionally, Steel frames were usually designed assuming that connections are ideally pinned or fully rigid. A semi-rigid connection, however, creates a balance between the two extreme approaches mentioned above. In this research, two full scales of Extended End Plate Connections (EEPCs) were tested. Mathematical and numerical models were used to analyse the connections, and close correlations were found between these models and the corresponding tested specimens, which confirmed the confidence in the experimental results. The experimental results obtained enrich the available test data about behaviour of EEPC. In addition, the purpose of studying EEPC experimentally is to compare the stiffness and moment-rotation curve of EEPCs with that of Cap Plate Connections (CPCs), which were tested in a previous work. CPCs have not been studied sufficiently in the literature. The results obtained show that the typical CPC reduces the connection stiffness and these results will make a valuable contribution to the available test data in the research area of CPC.

Investigation on Nd:YAG Laser Weldability of Zircaloy-4 End Cap Closure for Nuclear Fuel Elements

  • Kim, Soo-Sung;Lee, Chul-Yung;Yang, Myung-Seung
    • Nuclear Engineering and Technology
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    • 제33권2호
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    • pp.175-183
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    • 2001
  • Various welding processes are now available for end cap closure of nuclear fuel element such as TG(Tungsten Inert Gas) welding, magnetic resistance welding and laser welding. Even though the resistance and TIG welding processes are widely used for manufacturing commercial fuel elements, they can not be recommended for the remote seal welding of a fuel element at a hot cell facility due to the complexity of electrode alignment, difficulity in the replacement of parts in the remote manner and a large heat input for a thin sheath. Therefore, the Nd:YAG laser system using optical fiber transmission was selected for Zircaloy-4 end cap welding inside hot cell. The laser welding apparatus was developed using a pulsed Nd:YAG laser of 500 watt average power with optical fiber transmission. The weldability of laser welding was satisfactory with respect to the microstructures and mechanical properties comparing with TIG and resistance welding. The optimum operation processes of laser welding and the optical fiber transmission system for hot cell operation in a remote manner have been developed The effects of irradiation on the properties of the laser apparatus were also being studied.

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차체구조용 박육부재의 단면형상변화에 따른 에너지흡수 특성 (Energy Absorbing Characteristics of Thin-Walled Members for Vehicles Having Various Section Shapes)

  • 차천석;정진오;이길성;백경윤;양인영
    • 한국정밀공학회지
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    • 제20권10호
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    • pp.177-182
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    • 2003
  • The front-end side members of automobiles absorb most of the energy in a case of front-end collision. The front-end side members are required to have a high stiffness together with easiness to collapse sequentially to absorb more impact energy. The axial static collapse test (5mm/min) was conducted by using UTM for form different types of members which have different cross section shapes; single hat, single cap, double cap, and double hat. The single hat shaped section member has the typical standard section, which the double hat shape section has a symmetry in the center to have more stiffness. As a result of the test, the energy absorbing characteristic was analyzed for different section shapes. It turned out that the change of section shape influence the absorbing energy, the mean collapse load and the maximum collapse load, and the relation between the change of section shape and the collapse mode.

봉단 용접부 와전류탐상의 기초적인 연구 (A Basic Study on Eddy Current Testing of End-Cap Welds)

  • 서동만;심기섭;권우주;김정하;박춘호
    • 비파괴검사학회지
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    • 제18권2호
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    • pp.85-91
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    • 1998
  • 핵연료 제작과정에서 봉단마개 용접부는 완벽한 품질이 요구되고 있다. 본 연구에서는 와전류탐상방법을 이용하여 봉단마개 용접부의 검사를 위한 기초적인 방법을 연구하였다. 봉단마개 용접부 와전류검사를 위한 주사속도와 와전류신호의 최대주파수를 찾았고 잡음신호제거를 위해 대역통과여파기(0-250Hz)론 사용하였다. 이러한 와전류탐상방법은 직경 0.35mm의 작은 핀홀결함에서도 좋은 감도를 얻을 수 있었다.

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Cuffs 구성 면에서 본 Sleeve의 기능성에 관한 연구 (A study on the function of sleeve for the construction of cuffs)

  • 박영득
    • 대한가정학회지
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    • 제24권3호
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    • pp.51-58
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    • 1986
  • This study is to investigate the Function of sleeve for the construction of cuffs. Three measuremental items of sleeve cap high, length of sleeve and puff quantity of upper sleeve cap are compared between when the experimental man raises righthand static pose. The wearing test is done in sewing cuffs of either fixing up cuffs or not-fixing up cuffs, and in no cuffs. Three measuremental items are pulled length from sleeve end, pulled length from side waist line, and pulled dimensions from waist line. 1. The result according to the length and dimensions variation caused by a change of sleeve cap high. 2. The results according to the length and dimensions variation caused by a sort of sleeve length. 3. The results according to the length and dimension variation caused by the puff quantity of sleeve cap.

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Polyadenylation Is Dispensable for Encapsidation and Reverse Transcription of Hepatitis B viral Pregenomic RNA

  • Lee, Hye-Jin;Lee, Jehan;Shin, Myeong-Kyun;Ryu, Wang-Shick
    • Molecules and Cells
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    • 제25권4호
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    • pp.545-552
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    • 2008
  • A hepadnaviruses replicates its DNA genome via reverse transcription of an RNA template (pregenomic RNA or pgRNA), which has a cap structure at the 5' end and a poly(A) tail at the 3' end. We have previously shown that the 5' cap is indispensable for encapsidation of the pgRNA. A speculative extension of the above finding is that the cap contributes to encapsidation via its interaction with the poly(A) tail, possibly involving eIF4E-eIF4G-PABP interaction. To test this hypothesis, poly(A)-less pgRNAs were generated via cleavage by a cis-acting hepatitis delta virus ribozyme sequence. We found that accumulation of the poly(A)-less pgRNA was markedly diminished, mostly likely due to its reduced stability. Importantly, however, the remaining poly(A)-less pgRNAs were nonetheless encapsidated and reverse transcribed normally when the reduced stability was taken account. Our finding clearly contradicts the notion that the poly(A) tail has any function in encapsidation and viral reverse transcription.