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Many studies have shown that students of different disciplines experience a high level of stress in university environments. It seems that mindfulness education can increase the ability of students to cope with stressful factors in university environments. The purpose of this study was to test the efficacy of a mindfulness training intervention program for college students. 38 students participated in the present study (58% female and 42% male, age: mean = 24.31, SD = 1.05). The students randomly were assigned to an experimental group (n = 20) and a control group (n = 18). The experimental group received an 8-week mindfulness training intervention program, but no the control group. At an 8-week follow-up, participants in the experimental group reported an improvement in response to stressors and perceived reduction of stress relative to participants in the control group. However, we observed no differences in stressors, response to stressors and perceived reduction of stress between the experimental and control groups. The findings indicate that a mindfulness training intervention delivered in the university setting may be an effective way to increase response to stressors and reduce perceived stress among college students.

This paper reviewed the research on the vibration of orthotropic circular membrane. We applied the large deflection theory of membrane and principle of virtual displacement to derive the governing vibration equations of circular membrane, solved it, and obtained the power series formula of nonlinear vibration frequency of circular membrane with all edges fixed. The paper gave the computational example and compared the frequency with different initial displacements, respectively. Results obtained from this paper provide some theoretical foundation for the research of orthotropic composite materials; meanwhile, the results provide some theoretical foundation for the research of nonlinear vibration of membrane.

The influence of the re-melting times on chemical composition, microstructure, and mechanical properties of revert alloy K452 were systemically investigated. It was shown that the key factor in the engineering application was the control of gas content and porosities level in revert alloy. By an advancing technology in combination with the superheat treatment, adding a small amount of alloying elements such as C, Al, Ti, and using ceramic foam filters during vacuum induction melting, the composition and mechanical properties of the revert alloy in addition of 50% scrap were similar to that in the virgin alloy, which has successfully been used in applications for nozzle vanes of some new gas turbines.

Nonlinear vibration computational problem of isotropic thin plates in large amplitude was investigated here. We applied the Von Kármán’s theory of thin plates to derive the governing equations of nonlinear free vibration of isotropic thin plates, and solved the governing equations by direct integration method combined with power series expansion method. We obtained the power series solution of the nonlinear vibration frequency of the rectangular thin plates with four edges simply supported. Finally, the paper gave the computational example and compared the two results from the large amplitude theory and the small one, respectively. Results obtained from this paper provide a new analytical computational approach for calculating the frequency of nonlinear free vibration of isotropic thin plates in large amplitude, and provide more accurate theoretical basis for the vibration control and dynamic design of plate structures.