Negative coefficients occur where there is a decrease in acoustic impedance across the reflecting interface.

当反射界面上下两侧的声波组抗降低时，反射系数就会出现负值。

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Returns an array containing field objects reflecting all the accessible public fields of the class or interface represented by this class object.

返回一field对象数组，映射该Class对象表示的类或接口中的所有可访问公共域。

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Returns an array of method objects reflecting all the methods declared by the class or interface represented by this class object.

返回一method对象数组，映射该Class对象表示的类或接口中声明的所有方法。

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