Search Results

The NMFTA’s Vehicle Cybersecurity Requirements Woking Group (VCRWG), comprised of fleets, OEMs and cybersecurity experts, has worked the past few years to produce security requirements for Vehicle Network Gateways. Vehicle Network Gateways play an important role in vehicle cybersecurity – they are the component responsible for assuring vehicle network operations in the presence of untrustworthy devices on the aftermarket or diagnostics connectors. This paper offers security requirements for these gateways in design, implementation and operation. The requirements are specified at levels of abstraction applicable to all vehicle networks down to CAN networks specifically. These requirements were captured using the https://github.com/strictdoc-project/strictdoc requirements management tool and will be made available also as a ReqIF format along with the paper at https://github.com/nmfta-repo/vcr-experiment.

Recent studies have shown that for a given RON, fuels with a higher sensitivity (RON-MON) tend to have better antiknock performance at most knock-limited conditions in modern engines. The underlying chemistry behind fuel sensitivity was therefore investigated to understand why this trend occurs. Chemical kinetic models were used to study fuels of varying sensitivities; in particular their autoignition delay times and chemical intermediates were compared. As is well known, non-sensitive fuels tend to be paraffins, while the higher sensitivity fuels tend to be olefins, aromatics, diolefins, napthenes, and alcohols. A more exact relationship between sensitivity and the fuel's chemical structure was not found to be apparent. High sensitivity fuels can have vastly different chemical structures. The results showed that the autoignition delay time (τ) behaved differently at different temperatures. At temperatures below 775 K and above 900 K, τ has a strong temperature dependence.