Summary: The reaction between octaaminophenyl polyhedral oligomeric silsesquioxane (OAPS) and 2,2′‐(1,3‐phenylene)‐bis(4,5‐dihydro‐oxazoles) (PBO) over different temperature ranges was confirmed by FT‐IR spectroscopy. The OAPS was used to modify benzoxazine (BZ) in the presence of PBO. The novel polybenzoxazine (PBZ)‐PBO/OAPS hybrid nanocomposite was prepared by solvent methods. Dynamic mechanical analyses indicated that the nanocomposites exhibited much higher Tg values than the pristine PBZ and PBZ‐PBO resin, and the storage modulus of the nanocomposites was maintained at higher temperatures, although only a small amount of OAPS was incorporated into the systems. Dynamic thermogravimetric analysis showed that the thermal stability of the hybrid was also improved by the inclusion of OAPS.DMA of PBZ (a), PBZ‐PBO (b), and PBZ‐PBO/OAPS nanocomposites (c–e).magnified imageDMA of PBZ (a), PBZ‐PBO (b), and PBZ‐PBO/OAPS nanocomposites (c–e).
In this study, we aim to propose a collision-free model on the interaction between pedestrians and cyclists on a shared road. First, we design an experiment to investigate the behaviors of pedestrians and cyclists in the interaction process. Three principles are presented for modeling based on the experimental observations, including the perception difference in the bidirectional and unidirectional scenarios, the difference in sensitivity on safety distance of pedestrians and cyclists, and the effect of distance and moving direction on the deceleration and steering behaviors. The model is proposed under the concept of subjective perception and behavioral decision-making. The heuristic of the path decision is that if a pedestrian (cyclist) decides to detour, he/she prefers the shortest route on the premise that a minimum safety distance is kept from the cyclist (pedestrian). The speed adjustment of both pedestrians and cyclists includes two parts: the expected speed determined by the available headway distance, and the deceleration coefficient determined by the distance between the cyclist and the pedestrian for the safety concern. The direction-related parameters are calibrated directly through the trajectories, while the speed-related parameters are calibrated with the cross-entropy method. The microscopic validation implies that the proposed collision-free model can potentially be used to simulate the microscopic interaction between pedestrians and the cyclist. It is also worth noting that the perception uncertainty of pedestrians could generate a big challenge to physical models on simulating the microscopic behaviors of pedestrians when the potential collision comes from the behind. The simulation of the mixed traffic reveals the difference in lane formation phenomena and the consequential conflict intensity between a cyclist and the crowd in bidirectional and unidirectional situations.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.