For the limitations as using the well-known film thickness equation in shape optimization,a new approach for shape optimization of hydrodynamic journal bearing following the general film thickness equation was proposed.

A general equation is established to calculate the deformation of continuous beams on many supports taking into consideration the stepped cross sections and unequal spans.

Based with the general equation of calculating inner force and deformation of uniformed-section beam and principle of limited element and matrix recursion,the general equation of calculating inner force and deformation of non-uniformed section beam with arbitrary constraint is reduced in this paper.

PSD along with time is described by general dynamic equation (GDE).

Based on the small disturbance theory and thermodynamic system matrix equations,a general matrix equation,which is used to calculate thermodynamic system power variation and thermal efficiency when the multi-parameters of the regeneration system are simultaneously changed on off-design conditions,is strictly deduced.

It s the first time that,based on exergy balance equations,a general matrix equation for regenerative systems of fossil fired power stes has been deduced,with which the exergy loss distribution in regenerative systems of different power sets can easily be calculated.