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Der vorliegende Schlussbericht fasst die Ergebnisse des dreieinhalbjährigen Verbundvorhabens KOMET zusammen, in dem skalierbare GNSS-Korrekturdaten für das autonome Fahren in innerstädtischen Bereichen entwickelt, analysiert und umgesetzt wurden., This final report compiles the results of the three-and-a-half-year joint project KOMET, in which scalable GNSS corrections for autonomous driving in urban areas were developed, analysed and implemented.

One of the most important functions for the safety of autonomous driving is the self-localisation of a moving platform. The GNSS (Global Navigation Satellite System) sensor is - compared to other sensors as, e.g., video, radar or camera - the only sensor that provides absolute positioning. Under clear sky conditions, GNSS positioning methods yield high level of accuracy and integrity. Poor signal propagation conditions make precise GNSS positioning challenging under urban conditions where multipath degrades the attainable accuracy and integrity. In the last decades, various correction or mitigation approaches for multipath errors have been developed and tested, but for carrier phase observations it is still the most critical error with magnitudes of up to a quarter of the wavelength. Since the carrier phase multipath error is location dependent, this property can be used to construct a correction map. In this paper, we report on the necessary steps to construct such a multipath correction map. The carrier phase error is a function of the multipath characteristics and the extra path delay. Hence, it is dependent on the distance to the reflection surface. Using a 3D building model, the geometry between the building and potentially multipath affected satellite signals is established to obtain one periodic cycle of the carrier phase error. A pseudo-kinematic experiment in an urban environment is planned and designed based on simulation studies of a ray-tracing algorithm to ensure ideal receiving properties for multipath signals in a realistic scenario. Two different approaches of carrier phase residuals will be compared to derive the multipath error from the observations. Firstly, double difference (DD) residuals are computed. Secondly, carrier phase residuals extracted from a positioning engine will be analysed. Finally, the developed functions are evaluated in the context of generating GNSS multipath correction maps for moving platforms

Yu Wei, Jiayao Fu, Wenjing Wu, Pengfei Ma, Le Ren, Zimei Yi, Junhua Wu Department of Prosthodontics, School and Hospital of Stomatology, Tongji University and Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai, People’s Republic of ChinaCorrespondence: Junhua WuDepartment of Prosthodontics, School and Hospital of Stomatology, Tongji University and Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai, People’s Republic of ChinaTel +86 21-66313729Email wujunhua_sh@tongji.edu.cnPurpose: Emerging evidence has indicated that oxidative stress (OS) contributes to periodontitis. Periodontal ligament cells (PDLCs) are important for the regeneration of periodontal tissue. Quercetin, which is extracted from fruits and vegetables, has strong antioxidant capabilities. However, whether and how quercetin affects oxidative damage in PDLCs during periodontitis remains unknown. The aim of this study was to assess the effects of quercetin on oxidative damage in PDLCs and alveolar bone loss in periodontitis and underlying mechanisms.Materials and Methods: The tissue block culture method was used to extract human PDLCs (hPDLCs). First, a cell counting kit 8 (CCK-8) assay was used to identify the optimal concentrations of hydrogen peroxide (H2O2) and quercetin. Subsequently, a 2,7-dichlorodihydrofluorescein diacetate (DCFH-DA) probe, RT-qPCR, Western blotting and other methods were used to explore the effects of quercetin on OS in hPDLCs and the underlying mechanism. Finally, quercetin was administered to mice with periodontitis through gavage, and the effect of quercetin on the level of OS and alveolar bone resorption in these mice was observed by immunofluorescence, microcomputed tomography (micro-CT), hematoxylin and eosin staining (H&E) staining and so on.Results: Quercetin at 5 μM strongly activated NF-E2–related factor 2 (NRF2) signaling, alleviated oxidative damage and enhanced the antioxidant capacity of