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Panoramic images can provide critical information for Advanced Driving Assistance Systems (ADAS), such as parking spaces and surrounding vehicles. However, the vehicle in the bird's-eye view image is severely distorted and incomplete, and the visual information becomes very blurred in some illumination insufficient environments. If the driver cannot see the surrounding environment information, the risk of collision will increase, especially during parking. To better percept the local environment with the help of panoramic images, we use panoramic image segmentation results to construct a virtual surround view monitoring system to provide drivers with clearer perception information. Firstly, a lightweight segmentation network is redesigned based on SegNet, which will improve the accuracy of the segmentation without increasing the model’s inference time. Secondly, we build an augment visualization around view monitor (AV-AVM) system with regards to the segmentation results.

The synthetic paraffinic kerosine (SPK) produced via HEFAs is of great interest for civil aviation industry as it exhibits an excellent thermal oxidative stability with significantly lower particulate matter emission. However, due to its aromatic free characteristics, the widespread use of SPK is limited by its compatibility with non-metal materials such as fuel tank elastomers. In this research the compatibility of SPK and its blends with widely used aircraft fuel tank elastomers were systematically studied. Experimental results demonstrated the volume swellability of all selected materials showed a linear relationship with volume percentage of No.3 jet fuel in SPK blend. The increase of volume percentage of No.3 jet fuel in the SPK blend increased volume swellability for all materials except fluorosilicone gasket.

The impacts of aromatic contents in the aviation jet fuel on the volume swell of fuel tank polythioether and polysulfide sealants were systematically studied in this research. The experimental results revealed the sealant volume swell was dramatically increased as the aromatic content in the fuel was increased. The volume of the PR 1440 polysulfide manganese cured sealant was shrunk when the sealant was soaped in the aviation fuel with aromatic volume content less than 8 vol. % for 28 days at 93°C. The volume of the tested polythioether sealants was never shrunk at the same operating conditions. The experimental results also demonstrated the addition of various additives into the aviation fuel could effectively increase the volume swell of the sealant, increasing the sealant sealing properties.

The effects of charge non-uniformity on autoignition of methane/air mixtures in a motored engine are investigated analytically using a varying global kinetic data model derived from the results of a detailed chemical kinetic scheme under similar conditions in a simple adiabatic constant volume reactor. These derived varying global kinetic data model was implemented in the CFD KIVA-3 code. The relative contribution of fluid motion generated by piston motion, heat transfer, chemical reactivity of the cylinder charge and swirl movement to the inhomogeneities in the properties of the cylinder charge and their consequent effects on the evolution of the autoignition process are presented and discussed.

The paper examines the rapid compression process of methane-air mixtures while using a zero-dimensional simulation and a detailed chemical kinetic scheme involving 137 reaction steps for methane-air combustion with an account made for heat transfer. The results of this simulation are compared with the corresponding values obtained when using multi-dimensional CFD simulation of the temporal and spatial evolution of the physical properties inside the cylinder while using KIVA-3 code both for reactive and non-reactive “methane”-air mixtures. The reaction rate data used in the code were overall rates of varyingly fitted data based on results of the full detailed kinetic scheme under the same local conditions. The effects of the non-uniformity in the charge physical properties due to heat transfer and compression effects on the evolution of the chemical processes leading to autoignition are presented and discussed.