• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.12
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• pp.1367-1372
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• 2014

As the awareness of the environmental crisis has recently increased around the world, numerous studies in the transport industry have been conducted to solve this problem through lightweight car bodies. The hot-stamping process has been presented as solution to achieve a light weight. Hot-stamping is a method that is used to obtain ultra-high strength steel (1,500 MPa or greater) by simultaneously forming and cooling boron steel in a press die after heating it to a temperature of $900^{\circ}C$ or above. This study involved a, fundamental examination of laser parameters to investigate the laser weldability of boron steel. As a result, the following optimum parameters for the shielding gas were found: Q = 20 l/min, ${\alpha}=40^{\circ}$, d = 20mm, and l = 0 mm. The hardness of butt weldment increasesed sharply as a result of martensite formation at the fusion zone.

• Korean Journal of Veterinary Research
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• v.36 no.4
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• pp.949-966
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• 1996

To establish the method for the most effective radiography and fluoroscopy, the abdominal organs of cats were investigeted using omnidirectional angles with the center of the body as the axis using an omnidirectional protective shielding X-ray system and a $360^{\circ}$ rotary restraint unit for use in small animals. The organs examined were the diaphragm, liver, stomach, colon, spleen and kidney. The results obtained in the present study were as follows: 1. Regardless of gas in the stomach present or not, it was feasible to distinguish the left and right crura in the lumbar portion of diaphragm in the oblique projection inclined over $30^{\circ}$ and under $90^{\circ}$ from the lateral projection. 2. Outlines of the exterior left lobe and the interior right lobe of the liver were observed in the oblique image inclined up to $60^{\circ}$ from the lateral image, while that of the exterior right lobe was noted in the oblique image inclined up to $60^{\circ}$ from the ventrodorsal-dorsoventral images. 3. It was necessary to have gas present in the stomach for detailed morphological observations of the stomach. It was most clearly observed in the right $30^{\circ}$ ventral-left dorsal oblique projection($120^{\circ}$ image) and the left $60^{\circ}$ dorsal-right ventral oblique projection($300^{\circ}$ image). 4. Morphology of the colon was observable in detail by the oblique projection inclined over $30^{\circ}$ from the lateral projection. 5. To observe the whole spleen it was required to have images from the ventrodorsal projection ($90^{\circ}$ image) to the right $60^{\circ}$ ventral-left dorsal oblique projection ($150^{\circ}$ image) as well as those from the dorsoventral projection ($270^{\circ}$ image) to the left-right lateral projection $0^{\circ}$ image). 6. Dorsal and ventral sides of the kidney were observable in the oblique images inclined $30^{\circ}$ from the lateral image. 7. Considering above findings collectively, it was thought that the results of present study might be useful for the analysis of abnormalies in each organ of cat.