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This paper estimates the changes of industrial embodied energy consumption in China between 1997 and 2007, and applies a structural decomposition analysis (SDA), based on non-competitive (import) input-output tables, to analyze the sources of change of China’s energy consumption from 1997 to 2007. Results show that China’s energy consumption increased sharply, especially after the accession to WTO. The SDA results indicate that the improvement of energy efficiency during 1997-2007 significantly reduced energy consumption in China while the growth of final demand was the key driver of China’s energy consumption. In addition, distribution of final demand with the declining share of consumption and the increasing share of export push energy consumption upward.

Study on new absorption materials is important to the sound stealth of targets underwater. The simpler formulae of calculating multiple-layer absorption model is educed with transferring matrix. By numerical simulating, the relation between model’s acoustic characteristics and material parameters of each layer is provided.The study shows that a better performance is acquired when material Young’s modulus changed dynamically with frequency by a certain rule. On these basises, simulation contrast of the absorbing performances between styrene-butadiene rubber(SBR) and Spray Poiyurea Elastomer(SPUA) was carried out. The simulating result and the experiment provided that SPUA has good performance.

The laconic calculating formulae of arbitrary multiple-layer model’s acoustic characteristics are introduced with sound transmission theoretics in multilayer mediums. Taking properties of viscoelastic material in account, the sound absorption characteristics of multiple-layer model covered with viscoelastic material underwater are calculated using formulae deduced. By numerical analysis, the relation between absorption model and material parameters is simulated and the effect of proportion among layers’ natural impedance on acoustic characteristics of sound absorption model is analyzed. Then the method of designing sound absorption model by multiple-layer structures each layer natural impedance is studied. The result is of significance to devising sound absorption material and model.