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The purpose of this paper is to develop accurate model and simulation of mechanical power transmission within roller‐screw electromechanical actuators with special attention to friction, compliance and inertia effects. Also, to propose non‐intrusive experiments for the identification of model parameters with an integrator or system‐oriented view.

At system design level, the actuation models need to reproduce with confidence the energy losses and the main dynamic effects. The adopted modelling methodology is based on non‐intrusive measurements taken on a standard actuator test‐bench. The actuator model is first structured with respect to the bond‐graph formalism that allows a clear identification of the considered effects and associated causalities for model implementation. Various approaches are then combined, mixing blocked or moving load, position or torque control and time or frequency domains analysis. The friction representation model is suggested using a step‐by‐step approach that covers a wide domain of operation. The model is validated under varying torque and speed conditions.

A structured model is introduced with support of the bond‐graph formalism. Combining blocked/moving load and time/frequency domain experiments allows the development of progressive model identification. An advanced friction representation model is proposed including the effects of speed, transmitted force, quadrant of operation and roller‐screw preload.

Mechanical transmission energy losses and dynamics are modelled in a system‐oriented view without massive need to confidential design parameters. Not only speed but also load and operation quadrant effects are reproduced by the proposed friction model. The non‐intrusive experimental procedure is made consistent with use of a standard actuator test‐bench.

The purpose of this study is to assess the adherence to MedDiet among adults during the COVID-19 pandemic and the economic crisis, using the validated 14-item MedDiet assessment tool.

A quantitative research approach, based on the distribution of an online survey throughout the social media platforms, via networking, was the applied method. The structure of the survey included the socio-economic and demographic data along with the weekly adherence to physical activity; and the validated MedDiet assessment tool. The target population included 1,030 Lebanese adults from all provinces. Descriptive statistics were used to explore the characteristics of the sample population. Adherence to the MedDiet was determined by the Med-Diet score ≥ 9. Significant differences among the variables and the adherence to the MedDiet were examined using the chi-square test.

Mean adherence to the MedDiet was found to be lower than an adequate score among 60.8% of participants [mean adherence 8/14 < 9 (S.D. 2.2)]. Participants from North Province, those aged 45 years and above, university graduates, participants with an average income and those who exercised for a minimum of 30 min for three times/week had a higher mean of adherence compared to other groups. Higher percentage of those who exercised had adequate adherence compared to those who exercised less or did not. More than 50% of the participants consumed olive oil, vegetables, red meat, butter/margarine, sugary drinks, commercial sweets and sofrito according to recommendations. Less than 50% of the participants consumed fruits, nuts, fish and wine according to the MedDiet standards. More men consumed fruits (55.1%), wine (21%), fish (29%) and nuts (48.5%) than women according to the MedDiet recommendations; however, more women consumed legumes (69.7%) and Sofrito (88.4%) than men, in addition more women preferred consuming chicken over meat (72.3%).

The findings call for an urgent need of spreading national awareness among adult population in Lebanon to increase the adherence to MedDiet. To add, information gained from this study serve to help understanding nutritional behavior during the COVID-19 pandemic and the economic crisis, so public health authorities can start planning to save the threatened health-care system and preserve the wellness of the population.