4 research outputs found
Collective Perception: A Safety Perspective
Vehicle-to-everything (V2X) communication is seen as one of the main enabling technol-ogies for automated vehicles. Collective perception is especially promising, as it allows connected traffic participants to âsee through the eyes of othersâ by sharing sensor-detected objects via V2X communication. Its benefit is typically assessed in terms of the increased object update rate, redun-dancy, and awareness. To determine the safety improvement thanks to collective perception, the authors introduce new metrics, which quantify the environmental risk awareness of the traffic par-ticipants. The performance of the V2X service is then analyzed with the help of the test platform TEPLITS, using real traffic traces from German highways, amounting to over 100 h of total driving time. The results in the considered scenarios clearly show that collective perception not only con-tributes to the accuracy and integrity of the vehiclesâ environmental perception, but also that a V2X market penetration of at least 25% is necessary to increase traffic safety from a ârisk of serious traffic accidentsâ to a âresidual hypothetical risk of collisions without minor injuriesâ for traffic participants equipped with non-redundant 360° sensor systems. These results support the ongoing world-wide standardization efforts of the collective perception service
Collective Perception: A Safety Perspective
Vehicle-to-everything (V2X) communication is seen as one of the main enabling technologies for automated vehicles. Collective perception is especially promising, as it allows connected traffic participants to “see through the eyes of others” by sharing sensor-detected objects via V2X communication. Its benefit is typically assessed in terms of the increased object update rate, redundancy, and awareness. To determine the safety improvement thanks to collective perception, the authors introduce new metrics, which quantify the environmental risk awareness of the traffic participants. The performance of the V2X service is then analyzed with the help of the test platform TEPLITS, using real traffic traces from German highways, amounting to over 100 h of total driving time. The results in the considered scenarios clearly show that collective perception not only contributes to the accuracy and integrity of the vehicles’ environmental perception, but also that a V2X market penetration of at least 25% is necessary to increase traffic safety from a “risk of serious traffic accidents” to a “residual hypothetical risk of collisions without minor injuries” for traffic participants equipped with non-redundant 360° sensor systems. These results support the ongoing worldwide standardization efforts of the collective perception service
Prioritizing Relevant Information: Decentralized V2X Resource Allocation for Cooperative Driving
Cooperative driving is a promising approach to increase traffic efficiency and safety but requires high Vehicle-to-Everything (V2X) communication performance for coordinating and executing a cooperative maneuvers, especially in scenarios with high vehicle densities under congested channel conditions. Recent studies identified that content-agnostic congestion control mechanisms deployed in decentralized V2X networks maintain the radio communication performance under congested channel conditions but severely degrade the communication performance from the application perspective, such as for cooperative driving, as focused in this paper. Thus, we propose a relevance-aware resource allocation mechanism for decentralized V2X networks that prioritizes vehicles with relevant information and counteracts channel conditions. Our evaluation results show that our proposed approach maintains the radio communication performance and significantly increases the communication performance from the application perspective compared to content-aware resource allocation and content-agnostic congestion control mechanisms
Electrochemically Formed Na<sub><i>x</i></sub>Mn[Mn(CN)<sub>6</sub>] Thin Film Anodes Demonstrate Sodium Intercalation and Deintercalation at Extremely Negative Electrode Potentials in Aqueous Media
The development of
electrode materials for Na-ion batteries has been substantially accelerated
recently with respect to application in grid energy storage systems.
Specifically, development of Na-ion batteries operating in aqueous
media is considered more promising for this application due to safety
issues. Many different types of cathode materials for aqueous Na-ion
batteries have been proposed; however, the number and performance
of contemporary anode materials are still insufficient for practical
deployment. In this work, we demonstrate that electrochemically deposited
Na<sub><i>x</i></sub>MnÂ[MnÂ(CN)<sub>6</sub>] thin films are
very promising anode materials for aqueous Na-ion batteries. Na<sub><i>x</i></sub>MnÂ[MnÂ(CN)<sub>6</sub>] films exhibit (i)
very low half-charge potential ca. â0.73 V vs SHE (ca. â0.93
V vs SSC) being one of the lowest among those reported in the literature
for the electrode materials, which also inhibit hydrogen evolution
reaction; (ii) a specific capacity of ca. 85 mA h g<sup>â1</sup>; and (iii) only âŒ3% loss of capacity and high round-trip
efficiency (99.6%) after 3,000 cycles. Surprisingly, the choice of
the electrolyte composition has a very strong influence not only on
the intercalation process but also on the long-term performance of
battery anodes and their electrode surface morphology