Alice Munro is one of the famous Canadian writers and is renowned above all for the astonishing subtlety of her short stories.Her theme has often been the dilemmas of the female coming to terms with family, friends in...Alice Munro is one of the famous Canadian writers and is renowned above all for the astonishing subtlety of her short stories.Her theme has often been the dilemmas of the female coming to terms with family, friends in a small town. This paper attempts to make a brief introduction about the stories of Alice Munro's Runaway and explores the protagonist's choices in the dilemma situation, and then exposes the cruelty of reality is that they cannot get rid of the ineluctable reality of life. Escape is only a temporary action which cannot save them from endless triviality of life. What they should do is not to escape from life, but to adapt to the reality of life.展开更多
The traditional method of mechanical gear driving simulation includes gear pair method and solid to solid contact method. The former has higher solving efficiency but lower results accuracy; the latter usually obtains...The traditional method of mechanical gear driving simulation includes gear pair method and solid to solid contact method. The former has higher solving efficiency but lower results accuracy; the latter usually obtains higher precision of results while the calculation process is complex, also it is not easy to converge. Currently, most of the researches are focused on the description of geometric models and the definition of boundary conditions. However, none of them can solve the problems fundamentally. To improve the simulation efficiency while ensure the results with high accuracy, a mixed model method which uses gear tooth profiles to take the place of the solid gear to simulate gear movement is presented under these circumstances. In the process of modeling, build the solid models of the mechanism in the SolidWorks firstly; Then collect the point coordinates of outline curves of the gear using SolidWorks API and create fit curves in Adams based on the point coordinates; Next, adjust the position of those fitting curves according to the position of the contact area; Finally, define the loading conditions, boundary conditions and simulation parameters. The method provides gear shape information by tooth profile curves; simulates the mesh process through tooth profile curve to curve contact and offer mass as well as inertia data via solid gear models. This simulation process combines the two models to complete the gear driving analysis. In order to verify the validity of the method presented, both theoretical derivation and numerical simulation on a runaway escapement are conducted. The results show that the computational efficiency of the mixed model method is 1.4 times over the traditional method which contains solid to solid contact. Meanwhile, the simulation results are more closely to theoretical calculations. Consequently, mixed model method has a high application value regarding to the study of the dynamics of gear mechanism.展开更多
文摘Alice Munro is one of the famous Canadian writers and is renowned above all for the astonishing subtlety of her short stories.Her theme has often been the dilemmas of the female coming to terms with family, friends in a small town. This paper attempts to make a brief introduction about the stories of Alice Munro's Runaway and explores the protagonist's choices in the dilemma situation, and then exposes the cruelty of reality is that they cannot get rid of the ineluctable reality of life. Escape is only a temporary action which cannot save them from endless triviality of life. What they should do is not to escape from life, but to adapt to the reality of life.
基金supported by The 11th Five-year Defense Pre-research Fund of China (Grant No. 51305010387)
文摘The traditional method of mechanical gear driving simulation includes gear pair method and solid to solid contact method. The former has higher solving efficiency but lower results accuracy; the latter usually obtains higher precision of results while the calculation process is complex, also it is not easy to converge. Currently, most of the researches are focused on the description of geometric models and the definition of boundary conditions. However, none of them can solve the problems fundamentally. To improve the simulation efficiency while ensure the results with high accuracy, a mixed model method which uses gear tooth profiles to take the place of the solid gear to simulate gear movement is presented under these circumstances. In the process of modeling, build the solid models of the mechanism in the SolidWorks firstly; Then collect the point coordinates of outline curves of the gear using SolidWorks API and create fit curves in Adams based on the point coordinates; Next, adjust the position of those fitting curves according to the position of the contact area; Finally, define the loading conditions, boundary conditions and simulation parameters. The method provides gear shape information by tooth profile curves; simulates the mesh process through tooth profile curve to curve contact and offer mass as well as inertia data via solid gear models. This simulation process combines the two models to complete the gear driving analysis. In order to verify the validity of the method presented, both theoretical derivation and numerical simulation on a runaway escapement are conducted. The results show that the computational efficiency of the mixed model method is 1.4 times over the traditional method which contains solid to solid contact. Meanwhile, the simulation results are more closely to theoretical calculations. Consequently, mixed model method has a high application value regarding to the study of the dynamics of gear mechanism.
