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Abstract: In this paper, a new method based on generalized method of cells and laminate analogy approach was used to predict the elastic properties of short sisal fiber reinforced polypropylene composites. The effects of fiber volume fractions and fiber aspect ratios on the elastic properties of composites were studied by the new model and other models. Continuous fiber composite and layered composite, as two special cases were analyzed in detail by this new model. The results show that both fiber volume fraction and fiber aspect ratio have significant effects on the axial Young’s modulus. However, the fiber volume fraction has very small effects on the transverse Young’s modulus, axial shear modulus and axial Poisson’s ratio. The new model agrees better than other models with the experimental data. The elastic properties of composites with complex microstructures can be predicted efficiently by this new model. [Copyright &y& Elsevier]

With global warming and rapid urban growth, cities get warmer, which poses additional stress on human thermal comfort and health. Complex three-dimensional (3D) urban forms change radiation fluxes and shade patterns in cities, but most studies that link urban form to thermal exposure have traditionally investigated the horizontal, two-dimensional composition and configuration of urban landscapes. Supported by high-precision airborne LiDAR data and IKONOS satellite data, this study calculates 3D urban landscape metrics for central Nanjing, China, including vegetation above ground biomass (AGB), building volume (V B), standard deviation of building and vegetation heights (HSD B , HSD V), the building normalized compactness radio (nCR), sky view factor (SVF), surface roughness (SR), and shadow patterns (SP). Diurnal hourly mean radiant temperature (T mrt) is simulated using the UMEP (Urban Multi-scale Environmental Predictor) tool forced with fixed-point observation data for a typical hot summer day. Correlation and multiple regression analyses are conducted to investigate the relationship between the 3D form metrics and T mrt and to identify key factors that influence the thermal environment. T mrt varies spatially and diurnally and is strongly related to SP during the day, revealing the importance of solar access for modulating the thermal environment. AGB is negatively, but SVF, SP , and building nCR are positively correlated with daytime T mrt. At night, T mrt is more homogeneous across space and mainly impacted by the urban fabric's ability to lose heat. Open areas cool faster than areas with low SVF and complex urban forms with high building nCR. Findings from this study have great scientific and practical significance for optimizing urban landscape patterns from a human-centered heat exposure perspective and will guide planning and design strategies to promote thermally comfortable urban environments. • 3-Dimensional urban landscape pattern metrics were derived from Lidar Point Clouds. • Mean radiant temperature was simulated using meteorological observations as forcing. • Above ground biomass is negatively correlated with daytime mean radiant temperature. • Sky View Factor, shadow patterns, building compactness are positively correlated. • Open areas cool faster at night than dense, complex urban forms. [ABSTRACT FROM AUTHOR]