The coupon expires in one day, which means that the validity period of the coupon is coming, and the coupon will be used for one day. After one day, the coupon will expire, and after that, the coupon will be invalid. After expiration, the coupon cannot be used. Therefore, coupons should still be used up within the validity period, otherwise they will be invalid after expiration.
One-day overdue introduction
It means that it will expire in one day, which means that the deadline is clear, or because something or something has a clear shelf life, people can ride it at a glance.
Know its shelf life very clearly. Her shelf life is set at one day later. After this day, the shelf life of this thing may expire, and it will lose its original meaning.
Stiffness failure refers to the plastic deformation or vibration that the structure continues to bear or use normally. The simple understanding is that the structural deformation exceeds the required value, such as the beam does not meet the requirements of allowable deflection.
Stability and instability in the mechanics of materials mainly refer to the bending deformation of the slender compression bar, which makes the structure lose the bearing capacity of the workpiece, not because the strength is not enough, but because the compression bar can not maintain the original linear equilibrium state.