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  1. The US highway system features a huge flux of energy transportation in terms of weight, speed, volume, flow density, and noise levels, with accompanying environmental effects. The adverse effects of high-volume traffic cause health concerns for nearby residential areas. Both chronic and acute exposure to PM 2.5 have detrimental effects on respiratory and cardiovascular health, and motor vehicles contribute 25–35% of direct PM 2.5 emissions. In addition to traffic-related pollutants, residing near major roadways is also associated with exposure to increased noise, and both affect the health and quality of life of residents. While regulatory and policy actions may reduce some exposures, engineering means may offer novel and significant methods to address these critical health and environmental issues. The goal of this study was to harvest highway-noise energy to induce surface charge via a piezoelectric material to entrap airborne particles, including PM 2.5. In this study, we experimentally investigated the piezoelectric effect of a polymethyl methacrylate (PMMA) sheet and ethylene propylene diene monomer (EPDM) rubber foam on the entrapment of copper (II)-2,4 pentanedione powder (Cu II powder). Appreciable voltages were induced on the surfaces of the PMMA via mechanical vibrations, leading to the effective entrapment of the Cu II powder. The EPDM rubber foam was found to attract a large amount of Cu II powder under simulated highway noise in a wide range, of 30–70 dB, and at frequencies of 700–1300 Hz, generated by using a loudspeaker. The amount of Cu II powder entrapped on the EPDM rubber-foam surfaces was found to scale with the SPL, but was independent of frequency. The experimental findings from this research provide a valuable base for the design of a robust piezoelectric system that is self-powered by harvesting the wasted sound energy from highway noise and reduces the amount of airborne particles over highways for effective environmental control. 
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  2. Abstract Shortwave solar irradiance through building windows may have significant impacts on indoor thermal comfort, especially in near-window zones. Such effects change with intensity and spectral variations of the solar irradiance incident on building windows, which is related to the day of the year, time of day, orientation and dimension of the window, and atmospheric conditions. To assess the effects on thermal comfort, we derived a variable - mean radiant temperature delta based on a proposed spectrally-resolved method to represent the quantity of shortwave solar irradiance incident on occupants and be incorporated into PMV (predicted mean votes)-based thermal comfort models. By characterizing the variations of the calculated PMV values under different solar conditions, the influencing factors to indoor thermal comfort by shortwave solar irradiance were obtained and analyzed. Last, upon a series of parametric settings and numerical analysis, simplified statistical regression models were also established to directly predict spectrally-resolved mean radiant temperature delta and PMV values. This could be convenient and extensively to estimate the solar effects on indoor thermal comfort within the near-window zones. 
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  3. Abstract Solar near-infrared (NIR) selective glazing systems have been proposed by incorporating photothermal effects (PTE) of a nanoparticle film into building windows. From an energy efficiency perspective, the nanoscale PTE forms unique inward-flowing heat by heating up the window interior surface temperature under solar near-infrared, significantly improving the window thermal performance. Also, the PTE-driven solar heat gains are dynamic upon solar radiation and weather conditions. However, the PTE on annual building energy use has not been investigated thoroughly, due to the lack of an accurate and appropriate energy simulation method. In this study, we used the EnergyPlus energy management system to develop a parametric energy model and simulation approach in which a solar-temperature-dependent thermal model was embedded into the parametric energy simulation workflow. Applying this method, we examined the solar near-infrared-dependent PTE-induced thermal performances of glazing systems and their effects on annual heating energy use in representative cold climates (i.e., Zones 4, 5, and 6). The results show that the dynamic model considering the PTE demonstrated more heating energy savings, up to 11.64% in cold climates, as opposed to the baseline model that ignored the PTE. This work presents a method to model and simulate the dynamic thermal performance of windows with PTE. 
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