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In this study, two types of latex, Styrene–Butadiene Rubber (SBR) and Poly-Vinyl Acetate (PVA) were used as repair materials, and their various properties were examined. The assessments utilised Latex Modified Concrete (LMC) in ratios of 10%, 15%, and 20% to the weight of cement to investigate the properties of fresh and hardened concrete. The mechanical strength and durability of concrete were evaluated using porosity, water absorption, shrinkage, bonding behaviour, Coefficient of Thermal Expansion (CTE), and scaling resistance. The results indicated that LMC's mechanical properties improved, whereas its compressive strength decreased. The bonding strength between the LMC and the older concrete was more significant than between the Ordinary Portland Cement (OPC) and the substrate concrete. The SBR sample outperformed the PVA sample according to shrinkage and CTE results. Additionally, scaling resistance to deicing chemicals on concrete surfaces exposed to freezing-thawing cycles was satisfactory in concretes modified with both latexes. [ABSTRACT FROM AUTHOR]

In HTTP Adaptive Streaming (HAS), videos are encoded at multiple bitrates and spatial resolutions (i.e., representations) to adapt to the heterogeneity of network conditions, device attributes, and end-user preferences. Encoding the same video segment at multiple representations increases costs for content providers. State-of-the-art multi-encoding schemes improve the encoding process by utilizing encoder analysis information from already encoded representation(s) to reduce the encoding time of the remaining representations. These schemes typically use the highest bitrate representation as the reference to accelerate the encoding of the remaining representations. Nowadays, most streaming services utilize cloud-based encoding techniques, enabling a fully parallel encoding process to reduce the overall encoding time. The highest bitrate representation has a higher encoding time than the other representations. Thus, utilizing it as the reference encoding is unfavorable in a parallel encoding setup as the overall encoding time is bound by its encoding time. This article provides a comprehensive study of various multi-rate and multi-encoding schemes in both serial and parallel encoding scenarios. Furthermore, it introduces novel heuristics to limit the Rate Distortion Optimization (RDO) process across various representations. Based on these heuristics, three multi-encoding schemes are proposed, which rely on encoder analysis sharing across different representations: (i) optimized for the highest compression efficiency, (ii) optimized for the best compression efficiency-encoding time savings tradeoff, and (iii) optimized for the best encoding time savings. Experimental results demonstrate that the proposed multi-encoding schemes (i), (ii), and (iii) reduce the overall serial encoding time by 34.71%, 45.27%, and 68.76% with a 2.3%, 3.1%, and 4.5% bitrate increase to maintain the same VMAF, respectively, compared to stand-alone encodings. The overall parallel encoding time is reduced by 22.03%, 20.72%, and 76.82% compared to stand-alone encodings for schemes (i), (ii), and (iii), respectively. [ABSTRACT FROM AUTHOR]