• Title/Summary/Keyword: End cap

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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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    • v.2 no.1
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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.

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

  • 이정원;박춘호;고진현;정성훈;정문규
    • Journal of Welding and Joining
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    • v.7 no.2
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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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Analysis of the Dead Layer Thickness effect and HPGe Detector by Penelope Simulation (Penelope Simulation에 의한 불감층 두께 효과 및 HPGe 검출기 분석)

  • Jang, Eun-Sung;Lee, Hyo-Yeong
    • Journal of the Korean Society of Radiology
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    • v.12 no.7
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    • pp.801-806
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    • 2018
  • Germanium crystals have a dead layer that causes efficiency deterioration because the layer is not useful for detection but strongly weakens the photons. Thus, when the data provided by the manufacturer is used in the detector simulation model, there is a slight difference between the calculated efficiency and the measured efficiency.The shape and dimensions of the high purity germanium (HPGe) detector were determined by CT scans to accurately characterize the shape for the Monte Carlo roll simulation. It is found that the adjustment of the dead layer is a good match with the relative deviation of ${\pm}3%$ between the measurement efficiency and the simulation efficiency at the energy range of 50 - 1500 keV. Simulation data were compared by varying the thickness of the dead layer. The new Monte Carlo simulations were compared with the experimental results to obtain new blank layer thicknesses. The difference in dead layer results for the 1.5 mm thick end cap simulation model in 1.4 and 1.6 mm thick End Cap simulation models was a systematic error due to the accuracy of the end cap dimensions. After considering all errors including statistical errors and systematic errors, the thickness of the detector was calculated as $1.02{\pm}0.14mm$. Therefore, it was confirmed that the increase in the thickness of the dead layer causes the effect to be effected on the efficiency reduction.

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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    • v.23 no.5
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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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    • v.33 no.2
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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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Energy Absorbing Characteristics of Thin-Walled Members for Vehicles Having Various Section Shapes (차체구조용 박육부재의 단면형상변화에 따른 에너지흡수 특성)

  • 차천석;정진오;이길성;백경윤;양인영
    • Journal of the Korean Society for Precision Engineering
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    • v.20 no.10
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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.

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

  • Suh, D.M.;Sim, K.S.;Kwon, W.J.;Kim, J.H.;Park, C.H.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.18 no.2
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    • pp.85-91
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    • 1998
  • In nuclear fuel manufacturing process, end-closure welding has long been recognized as requiring very high integrity. In this basic study, ECT(eddy current testing) method for end-closure welding has been developed to detect end cap weld discontinuities for nuclear fuel safety. In order to improve the inspection reliability, the maximum scanning speed and the maximum frequency is investigated for end-closure welding inspection. The bandpass filter(0-250Hz) is used for removing noise effects. This study shows that ECT method is effective and sensitive for the detection of small defect(0.35mm diameter).

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

  • 박영득
    • Journal of the Korean Home Economics Association
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    • v.24 no.3
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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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    • v.25 no.4
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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.