• Journal of Auto-vehicle Safety Association
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• v.3 no.2
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• pp.5-10
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• 2011

Under the full frontal crash event, seatbelt system is the most typical and primary restraint device that prevents the second impact between an occupant and vehicle interior parts by limiting the forward motion of an occupant in the vehicle occupant packaging space. Today's restraint systems typically include the three-point seat belt with the pretensioner and the load limiter. A pretensioner preemptively tightens the seat belts removing any slack between a passenger and belt webbing which leads to early restraint of a passenger. After that a load limiter controls level of belt load by releasing the belt webbing to reduce occupant injurys. In this study, load characteristics of load limiters are optimized by the computer simulation with a MADYMO model for a frontal impact against the rigid wall at 56kph and then we suggest performance requirements. We derived optimum load characteristic from the results using four vehicle simulation models represented by the vehicle. Based on the results, we suggest the performance from the results of the second optimization using the simulation considering the design and the standardization. Finally, the performance requirements is verified by the sled tests including the load limiter device for the full vehicle condition.

• Journal of Chest Surgery
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• v.35 no.12
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• pp.882-889
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• 2002

Acute Complications of Remodelling Plasty of Costochondral Rib Cage For Pectus excavatum Recently, Remodelling Plasty of Costochondral Rib Cage has been introduced as an minimally invasive procedure and expanded its application for pectus excavatum. Outcomes and acute complications were reviewed Material and Method: A retrospective survey of 55 patients who underwent Remodelling Plasty of Costochondral Rib Cage from September, 1999 to February, 2002 was conducted to review complications, postoperative treatments, and outcomes. Result: Age ranged from 1 to 27 years(mean 11.4 $\pm$ 7.1). 35(64%) were less than 15-year old and 20(36%) were more than 15-year old. There were 44(80%) Male patients and 11(20%) female patients. Length of hospital stay was 7.8 $\pm$ 2.1 days for less than 15-Y-old group, 10.6 $\pm$ 6.2 days for more than 15-Y-old group(p ＝ 0.042) One substernal bar was inserted in 52 patients and two substernal bars were inserted in 3 patients. As for stabilizer, one lateral side was fastened in 15 patients and both lateral sides were fastened in 6 patients. In the less than 15-Y-old group, 4 patients needed stabilizer, whereas in the more than 15-Y-old group, 18 patients needed stebilizer(s)(p ＝ 0.000). Including all kinds of complications, 28(51 %)patients had postoperative complications. Of them, only 7 patients were treated for complications(C-tube insertion was done in 7 patients and reoperation for bar refixation or removal was done in 3 patients of them). Conclusion: Most complications after Remodelling Plasty of Costochondral Rib Cage For Pectus Excavatum were trivial without treatment although C-tube drainage was needed in some patients. However bar displacement such as rotation and lateral sliding should be corrected as soon as detected in order not to remove the bar(the worst situation).