Objective To explore the relation of attention deficit and hyperactivity disorder with sleep disorder in children.

However,the interaction among the shape and location of gas pin,gas pressure parameters,and traditional molding parameters often caused injection molding defects such as shine mark, gas finger mark, knit line and so on.

From the test course of environmental stress screen,this paper establishes a mathematic model,deduces a formula to calculate the proportion of element defects,and presents a method to calculate imported defects indirectly.

Legitimacy perspective in institutional theories, regarding the process of growth of new ventures as a process of legitimization, can be used to explain "the liability of newness", the failure of entrepreneurship and the growth of new ventures.