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In this study, a patient-specific carotid artery model was analyzed with an open source program foam-extend. The research includes the effect of arterial wall deformation by fluid-structure analysis. Pulsatile velocity cycle is trained for 144 patients with different hemodynamic parameters, by machine learning algorithm using blood flow velocity measured from 337 points of the carotid artery. Data used for training is obtained from an open source in the literature. Here, the machine learning algorithm was created by the help of an open source code Phyton. Then, using trained values of machine learning, and the known systole and diastole blood pressures for a specific chosen patient, the patient-specific pulsatile velocity cycle was estimated. The estimated pulsatile velocity cycle was then fitted to Fourier series. This pulsatile velocity cycle is used as the input boundary condition for the model analyzed in foam-extend. The outlet boundary condition, pulsatile pressure cycle is found by 4-Element Windkessel algorithm. Wall shear stresses and time averaged wall shear stresses were obtained for both the rigid and fluid structure interaction models, and variation of displacement throughout the pulsatile cycle was found for the FSI model. Wall shear stresses, velocity, and displacements were obtained high at peak systole, consistent with pulsatile cycles. Like the wall shear stresses, the time averaged wall shear stresses for the FSI model were also found lower than the rigid model. The wall shear stresses showed an increase towards the exit of internal and external carotid artery. [ABSTRACT FROM AUTHOR]

The competence around the elevator marjet place has resulted in diminish of the concept of energy efficiency only to energy consumption on running. As a result, conventional hydraulic elevators are ranked in the lowest category. In fact, the energy efficiency includes energy equivalence of service and maintenance costs beside energy consumption on running and idle conditions for the elevators. The design of the hydraulic elevators is an important factor affecting energy consumption. Keeping the oil temperature under control is one of the essential factors which improves energy saving, running performance and service life. Counter-weighing on hydraulic elevator systems haven't used widely so far, but its usage increases by changing face of market strategies in order to decrease energy consumption. Thermal-equilibrium temperature and energy consumption can be significantly reduced by means of counter-weighing especially for intensively used elevators. In this paper, the effects of the designs considering thermal equilibrium temperature and counter-weighting on energy efficiency are investigated for the elevators. [ABSTRACT FROM AUTHOR]