An Improved Optimization Function to Integrate the User's Comfort Perception into a Smart Home Controller Based on Particle Swarm Optimization and Fuzzy Logic.

Scheduling residential loads for financial savings and user comfort may be performed by smart home controllers (SHCs). For this purpose, the electricity utility's tariff variation costs, the lowest tariff cost schedules, the user's preferences, and the level of comfort that each load may add to the household user are examined. However, the user's comfort modeling, found in the literature, does not take into account the user's comfort perceptions, and only uses the user-defined preferences for load on-time when it is registered in the SHC. The user's comfort perceptions are dynamic and fluctuating, while the comfort preferences are fixed. Therefore, this paper proposes the modeling of a comfort function that takes into account the user's perceptions using fuzzy logic. The proposed function is integrated into an SHC that uses PSO for scheduling residential loads, and aims at economy and user comfort as multiple objectives. The analysis and validation of the proposed function includes different scenarios related to economy-comfort, load shifting, consideration of energy tariffs, user preferences, and user perceptions. The results show that it is more beneficial to use the proposed comfort function method only when the user requires SHC to prioritize comfort at the expense of financial savings. Otherwise, it is more beneficial to use a comfort function that only considers the user's comfort preferences and not their perceptions.

Characterization of a pediatric rotary blood pump

Abstract Introduction A ventricular assist device (VAD) is an electromechanical pump used to treat heart failures. For designing the physiological control system for a VAD, one needs a mathematical model and its related parameters. This paper presents a characterization procedure for determining the model parameter values of the electrical, mechanical, and hydraulic subsystems of a pediatric Rotary Blood Pump (pRBP). Methods An in vitro test setup consisting of a pRBP prototype, a motor driver module, an acrylic reservoir, mechanical resistance and tubings, pressure and fluid flow sensors, and data acquisition, processing, and visualization system. The proposed procedure requires a set of experimental tests, and a parameter estimation algorithm for determining the model parameters values. Results The operating limits of the pRBP were identified from the steady-state data. The relationship between the pressure head, flow rate, and the rotational speed of the pRBP was found from the static tests. For the electrical and mechanical subsystems, the dc motor model has a viscous friction coefficient that varies nonlinearly with the flow. For the hydraulic subsystem, the pressure head is assumed to be a sum of terms related to the resistance, the inertance, the friction coefficient, and the pump speed. Conclusion The proposed methodology was successfully applied to the characterization of the pRBP. The combined use of static and dynamic tests provided a precise lumped parameter model for representing the pRBP dynamics. The agreement, regarding mean squared deviation, between experimental and simulated results demonstrates the correctness and feasibility of the characterization procedure.