也就是“市场自由与国家强制”关系的演变与历史变迁过程。
It is also the history of relation between market freedom and state constraint.
自由与平等之间的张力不可能总能令人满意地解决；但是，并没有令人信服的理由去豁免收养机构。法律理应是强制性的。
The tension between freedom and equality cannot always be resolved satisfactorily; but there are not compelling reasons to exempt adoption agencies. The law should be enforced.
对柴油机轴系扭振的研究，以往是先建立扭振当量系统，然后进行自由振动与强制振动计算。
In the previous research on torsional. vibration of diesel engine shafting system, an equivalent system must be defined before calculating free vibration and forced vibration.
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