Iｔ has been confirmed that the composite peak accelerations by the controlled shock test using the shock machine in the several drop height are larger than the results by the freefall test. The cause is ｔｈｅ problem ｂｙ ｔｈｅ conventional equivalent drop theory. Then the assumption of package freight ｈａｓ modified from the conventional linear spring mass model to the attenuation model included the modification coeffcient of the input velocity change on the shock table. The coefficient estimated by the dynamic compression test suggests that the controlled shock test used by the proposed model can be possible to carry out more equivalent than the test using the conventional model. Some experiments are carried out to verify the effect of the proposed equivalent model with damping.

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［JISZ０238］ or ［ASTM(F88-06)］ are generally used as evaluation standards for verification of the finish of heat sealing. However, even if the requirements of these standards are met. pinholes and breaks will randomly occur and reliable heat sealing cannot be ensured. Conventional heatsealng methods have sought to maximize adhesive strength through cohesive adhesion of the melt state. However, protrusion of molten heat sealant beyond the heat sealing line ｃａｎ ｆoｒｍ ｐｏｌｙｍｅｒ ｂａlｌｓ ｔｈａｔ ｂｅｃｏｍｅ origins for breaks. Ruptures are caused immediately when critical stress for the cohesive adhesive state is reached. On the other hand, for the heat seal initially formed by surface adhesion, peeling occurs that functions to control stress breaking. ln this paper, the following points are discussed. 1）The mixing ｏｆ the two heat sealing conditions of adhesion on the inside and cohesion on the outer boundary of the heat sealing plane. 2）Making the heat sealing plane function effectively. 3）Controlling the generation of pinholes in heat sealing to control the root cause of heat seal breaks.

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