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The research aims to investigate the particularities of the regime of physical activity in adolescents from Timisoara, Romania. The work sample included 243 students: 37.9% in middle school and 62.1% in high school; 56.4% girls and 43.6% boys; aged 11 to 18. The work method was cross-sectional population study of the case study type. The results indicate practicing physical activities in order to lose weight or not gain weight in over half of respondents: 57.3% of middle school students and 57.9% of high school students, more often girls. The boys in the age group 15 to 18 practice more often both moderate and intense physical activities than girls, and the number of days per week in which students participate in sports classes is more reduced in high school compared to middle school.

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The paper presents the research into Romanian industrial in line gasoline blending. The paper is structured in three parts. First part presents an industrial bending system of a Romanian refinery. The second part contents a research of the blending mathematical model for petroleum products. The last part is a case study, regarding an industrial problem of the gasoline blending in a Romanian refinery. The study has reported similitude and differences between the optimal solution calculated by Blend Optimization and Supervisory System (BOSS) and the optimal solution obtained by using the author's model.

This paper presents the research regarding determination of kinetic model parameters from a catalytic cracking process. Starting from the Weekman kinetic model, the authors proposed a simplified version of this model and, based on experimental data form a catalytic cracking plant, they have numerical determined the coefficients of the new kinetic model. For this purpose, there were defined two objective functions; the first function is based on errors generated by estimation of the riser outlet temperature and the second function associated to the errors generated by the estimation of the gasoline yield. The minimization of the two objective functions has been solve by using Optimization Toolbox from MATLAB programming language. The results showed that the objective function that depends on gasoline yield allows more accurate estimation of the kinetic parameters from this model.