This article introduces the general issues and benefits of simulation in teaching and scientific research. Thereby, the author illustrates by making 3D drawings, assemblies, videos simulating machine structures for teaching Theoretical mechanics, Construction machine subjects and the author's studies in the mechanical field. The application of simulation in teaching is to create videos by using Solidworks software, simulating the operating principle of machine structures. After that, show the videos to the students, excite them and make the lesson lively. And the simulation application in scientific research is mentioned as the way to use 3D drawings and simulation videos to preview the research results, promptly fix the wrong places. Since then, the research is quick, cost reduction is not worth it. The results of this paper are to point out the unique benefits that contribute positively to simulation in teaching and in scientific research.

Binh Duong has rapidly transformed during the period 1999-2009, from a agricultural province to industrial one. The paper explores the shift of occupation-based social structure of Binh Duong during that period. Using the data sets of Census 1999 and 2009, the paper analyses the evolution of the occupational figure in Binh Duong by ten occupational categories and four occupational strata, and the differences in this figure by residence, gender, ethnic, and religious variables. Findings show that the occupational structure of Binh Duong is more developed than the one of the Southern Key Economic Zone. Its change in rural areas is more significant than in urban areas. There are not considerable differences by gender, ethnicity, and religiousness. The findings are suggestive for a further analysis using the data set of Census 2019 on the evolution of occupational figures in Binh Duong during the previous twenty years (1999-2019).