译：能量守恒和能量转换定律，不仅是工程实践的主要基础，而且也是物理、天文以及化学等方面推理的主要基础。
The law of conservation and transformation of energy is the chief basis of physical, astronomical and chemical reasoning as well as engineering practice.
能量守恒和能量转换定律是工程实践的主要基础。
The law of conservation and transformation of energy is the chief basis of engineering practice.
介绍了在非惯性系中建立动力学方程的方法，惯性系中拉格朗日方程在非惯性系中的转换形式，以及非惯性系中的能量定理和能量守恒定律的应用等研究成果。
Recent trends in the Lagrange equation's conversion and form from inertial system to non-inertial system, the application of energy theorem, energy conservation law, etc. are introduced.
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