• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.9
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• pp.182-194
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• 1999

Occupant injury in rear end impact is rapidly becoming one of the most aggravating traffic safety problems with high human suffering and societal costs. Although rear end impact occurs at relatively low speed , it may cause permanent disability due to neck injuries resulting from an abrupt moment, shear force , and tension/compression force at the occipital condyles. The analysis is performed for a combined occupant-eat model response, using the SAFE(Safety Analysis for occupant crash Environment) computer program. The computational results are verified by those from sled tests. A parameter study is conducted for many physical and mechanical properties. Seat design has been performed based on the design of experiment process with respect to five parameters; seat-back upholstery stiffness, torsional stiffness of the seat-back. An orthogonal array is selected from the parameter study. A good design has been found from the analysis results based on the orthogonal array. The results show that reductions of stiffness in seat-back upholstery and joint are the most effective for preventing neck injuries.

• Korean Journal of Veterinary Research
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• v.30 no.4
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• pp.395-400
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• 1990

A female Korean native calf with diprosopus was examined macroscopically and radiographically. Anterior head duplication (diprosopus) was observed and all structures caudal to it were normal. She had two complete mouths, four eyes and three ears. Single tongue was present in each oral cavity. The two tongues were joined at their base just posterior to the single epiglottis. Both oral cavities led jointly into a common pharynx and one esophagus. One laryngeal cavity communicated with one common trachea. The lower jaws were immobile because of overlapping mandibular rami. The atlas was complete, and two anterior articular cavities articulated with the lateral condyles of the occipital bones of each skull. The cerebrums were fused each other at their caudal portion, and the giri and sulci were underdeveloped. The cerebellums were also completely fused, and they had not characteristic appearance of the vermis. The spinal cord showed normal appearance.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.3
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• pp.130-138
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• 2000

The position of the automobile seat back is very important for the neck injury in the rear-end collisions. The effects of the position have been evaluated experimentally. A sled simulator is utilized with a velocity of 33 km/h. The position is varied by the angle of seat back from 25 to 65 degrees. All the configurations of the seat are fixed except the angle. The neck injuries are calculated by the equations accepted in the industries. Also, the sled tests with other velocities are carried out for the comparison study. Using the results of the test, the effects of seat back strength are discussed to minimize the occupant neck injury in rear end collisions.