Valve gear is regarded as stiffness in the traditional design and its elastic deformation in motion is neglected. This method is called static design.

配气凸轮传统的设计方法是把配气机构看成绝对刚体，不考虑它在运动时的弹性变形，这种设计也称为静态设计。

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Third, as I found out later, he had arthritis since he was a teenager, and after sitting at a desk all day he needed to rough-house with us to get the stiffness out of his joints.

第三，我后来才发现，他从十几岁就换上了关节炎，当他在桌子边上坐了一天之后，他需要和我们在家里玩去赶走关节的僵硬。

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Apart from stiffness, graphene is possibly better known as a potential silicon replacement.

除了刚度，石墨烯更著名的是其有可能替代硅。

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You may recognize it as stiffness on one side of the body, often seen in a club-like hand or foot.

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Children also showed improvement in hearing, skeletal rigidity or cardiovascular changes such as decreased arterial stiffness and improved vessel-wall density.

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Step 1 to 3 can be well practiced by using your mind, but when it comes to Step 4, take time for yourself, breath in and out, notice any discomfort in your body and breathe into this discomfort which is often experienced as coldness, stiffness, numbness, prickle, tightness etc.

FORBES: 5 Steps To Transform Your Life - Step 4