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This paper describes the complete integration of a fuzzy control of multiple evaporator systems with the IEEE 802.15.4 standard, in which we study several important aspects for this kind of system, like a detailed analysis of the end-to-end real-time flows over wireless sensor and actuator networks (WSAN), a real-time kernel with an earliest deadline first (EDF) scheduler, periodic and aperiodic tasking models for the nodes, lightweight and flexible compensation-based control algorithms for WSAN that exhibit packet dropouts, an event-triggered sampling scheme and design methodologies. We address the control problem of the multi-evaporators with the presence of uncertainties, which was tackled through a wireless fuzzy control approach, showing the advantages of this concept where it can easily perform the optimization for a set of multiple evaporators controlled by the same smart controller, which should have an intelligent and flexible architecture based on multi-agent systems (MAS) that allows one to add or remove new evaporators online, without the need for reconfiguring, while maintaining temporal and functional restrictions in the system. We show clearly how we can get a greater scalability, the self-configuration of the network and the least overhead with a non-beacon or unslotted mode of the IEEE 802.15.4 protocol, as well as wireless communications and distributed architectures, which could be extremely helpful in the development process of networked control systems in large spatially-distributed plants, which involve many sensors and actuators. For this purpose, a fuzzy scheme is used to control a set of parallel evaporator air-conditioning systems, with temperature and relative humidity control as a multi-input and multi-output closed loop system; in addition, a general architecture is presented, which implements multiple control loops closed over a communication network, integrating the analysis and validation method for multi-loop control networks designed for multi-evaporator systems.

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With the recent need to decrease energy use and promote indoor thermal comfort in overheating conditions, attention has been drawn to the passive cooling function of courtyards. This paper aims to determine the effect of proportions and orientations of courtyards on the indoor thermal performance of traditional houses in a warm, humid region so that this could guide further improvement and reinterpretation of this building type. The results of this parametric study were obtained through computer simulations of different cases with the aim to determine the influence of orientation, courtyard size and proportions on the indoor thermal energy balance and thermal comfort of a traditional building in a warm-humid region. Rather than promote passive cooling in the building, the findings suggest that the courtyard greatly increases solar heat gain, raising the temperature during the day. Higher solar heat gains and ventilation rates were observed in the courtyard cases with greater width and length. Nevertheless, this does not cause important differences in the average operative temperature of the entire building between the cases. As for orientation, lower heat gains were obtained in courtyards with the long axis-oriented east to west. Regardless of the cases, the study finally emphasizes the importance of the inhabitants controlling the opening of windows in the enclosed rooms since this could decrease the temperature by 1.1 °C from night to the early morning (23.00 hrs to 11.00hrs) and thus influence its thermal comfort. Conversely, opening the windows outside that time-lapse could cause an increase in temperature and more hours above the upper comfort limit.