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Commonly accumulator in rotary compressor is connected to main case by welding, which is space-saving and of high reliability, while big deformation of cylinder’s vane slot is usually resulted in to affect reliability and COP of compressor. Welding is a complex process including combustion, heat, structure, and so on. In this paper vane slot deformation in accumulator welding process was researched by both simulations and experiments. Firstly, oxyacetylene flame was simulated, and the temperature at different position of the flame was tested to adjust the parameters in the model. Secondly, heating procedure of accumulation welding was simulated to get the temperature distribution of compressor. And the distribution of the case temperature was tested by thermocouples, which showed the simulation result agreed well with the experiment. Thirdly, combustion-heat-structure coupled simulation model was established to get the deformation of vane slot, which also coincided with the experiment. Finally, based on the reliable simulation model, the principle of deformation was analyzed, which revealed the key factor of deformation is the heating difference between the taper pipe and the case pipe. Then the design was improved by shortening the case pipe to increase the heating area of taper pipe. And the deformation of vane slot almost disappeared, which was confirmed by simulation and experiment simultaneously. The fact of improvement ensured the rationality of the simulation model and the principle of vane slot deformation again.

The probability density evolution of structural dynamic prediction models under several times random loads are proposed in this paper. Firstly, the probability density of several times stochastic loads can be obtained from the probability density of single time stochastic load. The prediction models of structural reliability from time responses under several times stochastic loads with and without strength degeneration over time are derived using the stress-strength interference theory and probability density evolution method. The differential equation in the models can be solved using the forward finite difference method. The probability density functions of the structural strength redundancy at any time can be obtained. In the end, structural dynamic reliability can be calculated using integral method. The efficiency of the proposed method is demonstrated numerically through a speed reducer. The results have shown that the proposed method is practicable, feasible and gives reasonable accurate prediction.

From the point of view of game theory and through establishing the game model of the subject and object of marine ecological compensation, this paper makes a research on the balance mechanism the interests of marine ecological compensation. The results show that the optimal amount of capital investment of environmental protection enterprises for ecological compensation depends not only on energy conservation and emission reduction of itself as well as competition enterprises, but also on the policy support for ecological compensation. At the same time, it is limited by the public's understanding and acceptance for ecological compensation.

This paper studies the incentive mechanism of RSC in government regulation. On the condition of subsidies and punishment being an independent parameters, the government may choose three incentive programs: first is the program of subsidies and punishment simultaneous implementation, second is the program of only punishment, third is the program of only subsidies. We can educe that from the comparison of three different programs, the first program is the optimal incentive program. The results have important theoretical and practical significance to government making-decision of environmental policy. And the results laid the theoretical foundation to further study government and enterprise contracts.

Diode-pumped Nd:YAG lasers are promising sources of the new optical frequency standards at 532 nm that were recommended recently in the 9th CCDM. Molecular iodine has several strong absorption lines at the second harmonic of Nd:YAG laser near 532 nm, thus providing an absolute reference for frequency stabilization. In general, the 532 nm laser sources used in iodine-stabilized systems are commercial monolithic lasers, which are compact, efficient, and reliable, but are also expensive and complicated. Recently, we have frequency stabilized a self-developed single-frequency Nd:YAG-KTP laser to the Doppler-broadened (instead of Doppler-free) lines of iodine. That was the first time to stabilize a 532 nm laser to an absolute reference in China. Due to its concise structure, low cost, and the ability to resist more disturbance, the laser system is attractive in some certain industrial applications that require an absolute frequency reference but not very high stability.