Lowering the temperature of the road surface is one efficient way to alleviate the urban heat island effect. Therefore water-retaining asphalt mixture was produced by adding super absorbent polymer (SAP) containing cement mortar to the porous asphalt mixture. In this study, the water absorption capacity, mechanical strength and fluidity of the cured water-retaining mortar were investigated to determine the optimum SAP dosage in water-retaining mortar. Furthermore, the microstructure of the hardened water-retaining mortar was studied using scanning electron microscopy (SEM) to determine the morphology and distribution of SAP in the final product, which may help to understand the influence of SAP on water retention performance and decipher its underlying mechanism. Compared to the raw porous asphalt mixture, the water-retaining asphalt mixture showed good moisture susceptibility (retained stability (RS) ≥ 88.2%, tensile strength ratio (TSR) ≥ 81.8%), good rutting resistance (9336–10,552 times/mm) and low temperature crack resistance (3383–3621 MPa), as well as significant cooling effects (10–12 °C). The results illustrate that the prepared SAP water-retaining asphalt mixture has good potential in reducing dust and enhancing road performance.

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In this paper, a WLED communication system with SC-FDMA technique is proposed. OFDM is a promising technique to realize high-speed WLED communication system. However, because of the PAPR, the system performance can be significantly compromised by non-linear distortions in the transmission chain. Furthermore, the overload current due to peak signal power lead the WLED equipment over bright which is harmful to equipment life and human's eye. The novel WLED communication system proposed in this paper solved these problems by using SC-FDMA technique which has an inherent low PAPR property. The severity of PAPR performances expressed by CCDF curve and the BER performances under different modulation schemes are analyzed in this paper.

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