Prediction of Pressure Drop in Vertical Pneumatic Conveyors

This paper presents a steady state one-dimensional two-fluid model for gas-solid two-phase flow in a vertical riser. The model is solved using conservative variable approach for the gas phase, and fourth order Runge-Kutta method is used for the solid phase. The model predictions for pressure drop are compared with available experimental data and with Eulerian-Lagrangian predictions, and a good agreement is obtained. The results indicate that the pressure drop increases as the solid mass flow rate, particle size, and particles density increase. In addition, the model predictions for minimum pressure drop velocity are compared with experimental data from literature and the mean percentage error. MPE for minimum pressure drop velocity is -9.89%. It is found that the minimum pressure drop velocity increases as the solid mass flow, particle size and particle density increase, and decreases as the system total pressure increases

Study of burning out, knowledge and attitude of Egyptian psychiatrist towards COVID-19 pandemic

Background and aim: Coronavirus disease-2019 (COVID-19) is a new pandemic threatening people all over the world. This study assessed the prevalence of burnout, knowledge and attitude of Egyptian psychiatrists during COVID-19 pandemic and factors related. Methods: An online cross-sectional, descriptive study used an online questionnaire distributed through social media among a sample of Egyptian psychiatrists (the total number was 281 psychiatrists) work in different sectors of hospitals (general, governmental and private psychiatric hospitals). Results: Most of the participants were female (n = 182, n = 64.76%), age range: (27–66) years. One hundred sixty-five psychiatrists (58.71%) work in governmental psychiatric hospitals. The frequency of burnout was 31.07% (n=87) and associated with significant correlations of some sociodemographic data such as gender, place of work, years of experience, and other factors. Overall, 80.07% (n = 225) had sufficient knowledge, 75% (n = 212) had a positive attitude, no significant factor was associated with knowledge while gender, place of work and long of experience were significantly associated with positive attitude.&nbsp

Prediction of the spread of Corona-virus carrying droplets in a bus-A computational based artificial intelligence approach

Public transport has been identified as high risk as the corona-virus carrying droplets generated by the infected passengers could be distributed to other passengers. Therefore, predicting the patterns of droplet spreading in public transport environment is of primary importance. This paper puts forward a novel computational and artificial intelligence (AI) framework for fast prediction of the spread of droplets produced by a sneezing passenger in a bus. The formation of droplets of salvia is numerically modelled using a volume of fluid methodology applied to the mouth and lips of an infected person during the sneezing process. This is followed by a large eddy simulation of the resultant two phase flow in the vicinity of the person while the effects of droplet evaporation and ventilation in the bus are considered. The results are subsequently fed to an AI tool that employs deep learning to predict the distribution of droplets in the entire volume of the bus. This combined framework is two orders of magnitude faster than the pure computational approach. It is shown that the droplets with diameters less than 250 micrometers are most responsible for the transmission of the virus, as they can travel the entire length of the bus

Indoors ventilation in times of confinement by SARS-CoV-2 epidemic: A comparative approach between Spain and Italy

With the arrival of the SARS-CoV-2 coronavirus, the scientific academia, as well as policymakers, are striving to conceive solutions as an attempt to contain the spreading of contagion. Among the adopted measures, severe lockdown restrictions were issued to avoid the diffusion of the virus in an uncontrolled way through public spaces. It can be deduced from recent literature that the primary route of transmission is via aerosols, produced mainly in poorly ventilated interior areas where infected people spend a lot of time with other people. Concerning contagion rates, accumulated incidence or number of hospitalizations due to COVID-19, Spain, and Italy have reached very high levels. In this framework, a regression analysis to assess the feasibility of the indoor ventilation measures established in Spain and Italy, with respect to the European framework, is here presented. To this aim, ten cases of housing typology were and analyzed. The results show that the measures established in the applicable regulations to prevent and control the risk of contagion by aerosols are not adequate to guarantee a healthy environment indoors. The current Italian guidelines are more restrictive than in Spain, yet the ventilation levels are still insufficient in times of pandemic