• International Journal of Korean Welding Society
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• 제4권1호
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• pp.1-9
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• 2004

Continuously welded tracks, first introduced on train lines, are being used increasingly in Europe. And the different arc welding methods are only used on minor lines, private tracks and in the manufacturing of switches and crossings. Mobile flash butt welding belongs the future in rail welding on side if new tracks have to be erected. The following contribution reviews the processes available, usual test methods for welded rail joints and various applications.

• 한국조리학회지
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• 제3권
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• pp.259-270
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• 1997

The experiment was carried out to investigate the change of pH, total lipid, neutral lipid and phospholipid of pork portions which are picnic shoulder, loin, ham, boston butt and bacon belly during storage at 4$^{\circ}C$ weeks. The results obtained were as follows, 1. pH of butt, ham, bacon, picnic and loin stored at 4$^{\circ}C$ for 2 days were 6.3, 5.9, 5.8, 5.6 and 5.2 respectively. And then pH of pork portions increased gradually during storage period. 2. Total lipid content of the pork portions were 2.13% in ham, 2.78% in loin 4.55% in picnic, 5.74% in butt and 7.11% in bacon. During storage period, total lipid content decreased slightly. 3. In case of neutral lipid, the content in bacon, butt, picnic, loin and ham were 6.68%, 5.32%, 4.22%, 2.53%, and 1.88% respectively. During storage period, neutral lipid content decreased slightly. 4. Phospholipid content showed little differences among the portions. And then phospholipid content decreased significantly during storage period.

• KIEE International Transactions on Electrophysics and Applications
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• 제4C권1호
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• pp.15-20
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• 2004

This paper discusses electrical insulation characteristics at cryogenic temperature, especially focusing on partial discharge (PD) inception characteristics, for high temperature superconducting cables. In liquid nitrogen (L$N_2$) / polypropylene (PP) laminated paper composite insulation system, PD inception strength (PDIE) was evaluated in terms of volume effect and V-t characteristics. Different kinds of butt gap condition were applied in the experiments, using parallel plane and coaxial cylindrical cable samples. Experimental results revealed that the volume effect on PDIE could be evaluated by the statistical stressed liquid volume (SSLV) taking account the discharge probability not only in the butt gap but also in the other thin layers between PP laminated papers. Furthermore, the indices n of V-t characteristics at PD inception were estimated to be 80∼110, irrespective of the butt gap condition.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2006년 추계학술발표대회 개요집
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• pp.292-294
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• 2006

Many processes have been introduced to join PE pipes, but most of these methods have lots of disadvantages such as costs and lack of reliability, etc. Recently due to the benefits of cost, safety and reliability, the butt welding has been paid much attention to joint PE pipes. In case of butt welding, the heat plate which is used to melt PE pipes is the most critical equipment. In this study, after developing the heat plate of new shape, the PE double wall pipes with misalignments were butt-welded by using the conventional and developed heat plates and comparison of weld-zones and tensile test was performed. As the results of tensile test, weld-zones using developed heat plate have strength of $147.7{\sim}251.0%$ of weld-zones using conventional heat plate.

• Journal of Advanced Marine Engineering and Technology
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• 제33권4호
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• pp.517-523
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• 2009

Magnesium alloys have many advantages such as a low density, high strength/weight ratio and well recycle. And joining process is absolutely necessary to expand the field of application of magnesium alloy. The main problems of conventional process such as arc welding for magnesium alloy are the inflammability, a tendency toward crack formation and the appearance of porosity during solidification. Laser welding technology is a promising means for overcoming these difficulties. This study is related to the laser weldability of AZ31 magnesium alloy, an all-purpose wrought alloy with good strength and ductility. The effect of welding conditions on the weldability of butt joints was examined. Also, the mechanical properties of butt welded joints were investigated by tensile test and hardness test.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2004년도 춘계 학술발표대회 개요집
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• pp.255-257
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• 2004

This report presents S-N testing results of the butt and T-joint weldment which are produced by single sided welding with cenramic backing material. The specimen is designed in accordance with JISZ 3103 aid the test is peformed by the JSME S002. The nominal and hot spot stress based design S-N curves derived from fatigue tests are compared with the BS design curve. For butt and T-joint, it can be known that the double-sided butt welding process could be replaced by the single sided butt welding.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1747-1751
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• 2003

The paper shows properties such as vickers hardness, yielding and ultimate stresses for the weld zone of the butt and the lap jointed specimens, and compare maximum loads, stress-strain curves, deformation appearance after guided bending test and fracture appearance for butt and lap jointed specimens. The research in this experiment also shows the weldability of the butt joint specimen is better than that of the lap joint specimen using FSW with $2mm^{t}$ aluminum alloy sheet in milling machine.

• 한국압력기기공학회 논문집
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• 제11권2호
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• pp.40-44
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• 2015

The fatigue behavior of thermal butt fusion in safety class III high-density polyethylene (HDPE) buried piping for nuclear power plants was investigated using load-controlled bending fatigue on four-point bend test specimens. Based on the results, the presence of thermal butt fusion beads was confirmed to reduce the fatigue lifetime in the low- and medium-cycle fatigue regions while having a negligible effect in the high-cycle fatigue regions.

• International Journal of Naval Architecture and Ocean Engineering
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• 제7권5호
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• pp.833-847
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• 2015

Although the transverse butt weld method with ceramic backing strip has been widely used in various industrial fields for its fabricational convenience, it is rarely used in offshore industries since the fatigue strength of the weld joint has not been proved sufficiently. This study conducted fatigue tests for series of butt weld specimens with horizontal (2G) and vertical (3G) welding positions in order to verify the fatigue strength compared to S-N curve by DNV (Det Norske Veritas), IIW (International Institute of Welding) and Eurocode 3. The difference of the 2G specimens and the 3G specimens are investigated in terms of angular distortion and the effect on the fatigue strength are analyzed.

• Journal of Welding and Joining
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• 제34권6호
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• pp.20-27
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• 2016

This study deals with the proper conditions of the trail rolling method (TRM) for the prevention of the buckling welding distortion at the AA5083 GMA butt weldment. For it, the effect of the working conditions of TRM including the rolling depth and the rolling distance between the welding torch and the roller on the longitudinal welding shrinkage force of the weldment was evaluated by using 3 dimensional thermo-mechanical FE analyses. The longitudinal welding shrinkage force inducing the buckling welding distortion at the GMA butt weldment was mitigated with an increase in the rolling depth and the rolling distance between the welding torch and the roller. Based on the results, the proper conditions of trail rolling method were established to reduce the longitudinal welding shrinkage force of the GMA butt weldment to below the critical value corresponding to the bucking distortion.