@inproceedings{LoboFestagFacchi2023, author = {Lobo, Silas and Festag, Andreas and Facchi, Christian}, title = {Enhancing the Safety of Vulnerable Road Users}, booktitle = {2022 IEEE 96th Vehicular Technology Conference (VTC2022-Fall) Proceedings}, subtitle = {Messaging Protocols for V2X Communication}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-6654-5468-1}, issn = {2577-2465}, doi = {https://doi.org/10.1109/VTC2022-Fall57202.2022.10012775}, year = {2023}, language = {en} } @misc{OPUS4-3102, title = {International Journal on Advances in Security. 14(1\&2)}, editor = {Hof, Hans-Joachim and Gersbeck-Schierholz, Birgit}, publisher = {IARIA}, issn = {1942-2636}, url = {http://www.iariajournals.org/security/tocv14n12.html}, year = {2021}, language = {en} } @inproceedings{MaksimovskiFacchiFestag2021, author = {Maksimovski, Daniel and Facchi, Christian and Festag, Andreas}, title = {Priority Maneuver (PriMa) Coordination for Connected and Automated Vehicles}, booktitle = {2021 IEEE International Intelligent Transportation Systems Conference (ITSC)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-7281-9142-3}, doi = {https://doi.org/10.1109/ITSC48978.2021.9564923}, pages = {1083 -- 1089}, year = {2021}, language = {en} } @book{OPUS4-3107, title = {SECURWARE 2020: The Fourteenth International Conference on Emerging Security Information, Systems and Technologies}, editor = {Hof, Hans-Joachim and Popescu, Manuela and Yee, George}, publisher = {IARIA}, isbn = {978-1-61208-821-1}, issn = {2162-2116}, pages = {101}, year = {2020}, language = {en} } @unpublished{SongLyuJiangetal.2023, author = {Song, Rui and Lyu, Lingjuan and Jiang, Wei and Festag, Andreas and Knoll, Alois}, title = {V2X-Boosted Federated Learning for Cooperative Intelligent Transportation Systems with Contextual Client Selection}, publisher = {arXiv}, address = {Ithaca}, doi = {https://doi.org/10.48550/arXiv.2305.11654}, year = {2023}, abstract = {Machine learning (ML) has revolutionized transportation systems, enabling autonomous driving and smart traffic services. Federated learning (FL) overcomes privacy constraints by training ML models in distributed systems, exchanging model parameters instead of raw data. However, the dynamic states of connected vehicles affect the network connection quality and influence the FL performance. To tackle this challenge, we propose a contextual client selection pipeline that uses Vehicle-to-Everything (V2X) messages to select clients based on the predicted communication latency. The pipeline includes: (i) fusing V2X messages, (ii) predicting future traffic topology, (iii) pre-clustering clients based on local data distribution similarity, and (iv) selecting clients with minimal latency for future model aggregation. Experiments show that our pipeline outperforms baselines on various datasets, particularly in non-iid settings.}, language = {en} } @inproceedings{SongLyuJiangetal.2023, author = {Song, Rui and Lyu, Lingjuan and Jiang, Wei and Festag, Andreas and Knoll, Alois}, title = {V2X-Boosted Federated Learning for Cooperative Intelligent Transportation Systems with Contextual Client Selection}, booktitle = {CoPerception: Collaborative Perception and Learning, ICRA 2023 workshop}, url = {https://drive.google.com/file/d/1-OQAeNryd7-lksCTuWnhhyydpFSnw5On/view?usp=share_link}, year = {2023}, language = {en} } @article{BauderFestagKubjatkoetal.2024, author = {Bauder, Maximilian and Festag, Andreas and Kubjatko, Tibor and Schweiger, Hans-Georg}, title = {Data accuracy in Vehicle-to-X cooperative awareness messages: An experimental study for the first commercial deployment of C-ITS in Europe}, volume = {2024}, pages = {100744}, journal = {Vehicular Communications}, number = {47}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2214-2096}, doi = {https://doi.org/10.1016/j.vehcom.2024.100744}, year = {2024}, abstract = {Cooperative Intelligent Transportation Systems have achieved a mature technology stage and are in an early phase of mass deployment in Europe. Relying on Vehicle-to-X communication, these systems were primarily developed to improve traffic safety, efficiency, and driving comfort. However, they also offer great opportunities for other use cases. One of them is forensic accident analysis, where the received data provide details about the status of other traffic participants, give insights into the accident scenario, and therefore help in understanding accident causes. A high accuracy of the sent information is essential: For safety use cases, such as traffic jam warning, a poor accuracy of the data may result in wrong driver information, undermine the usability of the system and even create new safety risks. For accident analysis, a low accuracy may prevent the correct reconstruction of an accident. This paper presents an experimental study of the first generation of Cooperative Intelligent Transportation Systems in Europe. The results indicate a high accuracy for most of the data fields in the Vehicle-to-X messages, namely speed, acceleration, heading and yaw rate information, which meet the accuracy requirements for safety use cases and accident analysis. In contrast, the position data, which are also carried in the messages, have larger errors. Specifically, we observed that the lateral position still has an acceptable accuracy. The error of the longitudinal position is larger and may compromise safety use cases with high accuracy requirements. Even with limited accuracy, the data provide a high value for the accident analysis. Since we also found that the accuracy of the data increases for newer vehicle models, we presume that Vehicle-to-X data have the potential for exact accident reconstruction.}, language = {en} } @article{KoenigPaulaQuaschneretal.2024, author = {K{\"o}nig, Thomas and Paula, Daniel and Quaschner, Stefan and Schweiger, Hans-Georg}, title = {Influence of Blind Spot Assistance Systems in Heavy Commercial Vehicles on Accident Reconstruction}, volume = {24}, pages = {1517}, journal = {Sensors}, number = {5}, publisher = {MDPI}, address = {Basel}, issn = {1424-8220}, doi = {https://doi.org/10.3390/s24051517}, year = {2024}, abstract = {Accidents between right-turning commercial vehicles and crossing vulnerable road users (VRUs) in urban environments often lead to serious or fatal injuries and therefore play a significant role in forensic accident analysis. To reduce the risk of accidents, blind spot assistance systems have been installed in commercial vehicles for several years, among other things, to detect VRUs and warn the driver in time. However, since such systems cannot reliably prevent all turning accidents, an investigation by experts must clarify how the accident occurred and to what extent the blind spot assistance system influenced the course of the accident. The occurrence of the acoustic warning message can be defined as an objective reaction prompt for the driver, so that the blind spot assistance system can significantly influence the avoidability assessment. In order to be able to integrate the system into forensic accident analysis, a precise knowledge of how the system works and its limitations is required. For this purpose, tests with different systems and accident constellations were conducted and evaluated. It was found that the type of sensor used for the assistance systems has a great influence on the system's performance. The lateral distance between the right side of the commercial vehicle and the VRU, as well as obstacles between them, along with the speed difference can have great influence on the reliability of the assistance system. Depending on the concrete time of the system's warning signal, the accident can be avoided or not by the driver when reacting to this signal.}, language = {en} } @inproceedings{LoboNeumeierFernandezetal.2022, author = {Lobo, Silas and Neumeier, Stefan and Fernandez, Evelio and Facchi, Christian}, title = {InTAS: The Ingolstadt Traffic Scenario for SUMO}, booktitle = {SUMO User Conference 2020}, editor = {Alvarez Lopez, Pablo and Banse Bueno, Olaf Angelo and Armellini, Maria Giuliana and Behrisch, Michael and Bieker-Walz, Laura and Erdmann, Jakob and Fl{\"o}tter{\"o}d, Yun-Pang and Hilbrich, Robert and Nippold, Ronald and Rummel, Johannes and Schwamborn, Matthias and Wagner, Peter and Weber, Melanie}, publisher = {TIB Open Publishing}, address = {Hannover}, doi = {https://doi.org/10.52825/scp.v1i.102}, pages = {73 -- 92}, year = {2022}, language = {en} } @inproceedings{HegdeStahlLoboetal.2022, author = {Hegde, Anupama and Stahl, Ringo and Lobo, Silas and Festag, Andreas}, title = {Modeling Cellular Network Infrastructure in SUMO}, volume = {2}, booktitle = {SUMO Conference Proceedings}, publisher = {TIB Open Publishing}, address = {Hannover}, issn = {2750-4425}, doi = {https://doi.org/10.52825/scp.v2i.97}, pages = {99 -- 113}, year = {2022}, abstract = {Communication networks are becoming an increasingly important part of the mobility system. They allow traffic participants to be connected and to exchange information related to traffic and roads. The information exchange impacts the behavior of traffic participants, such as the selection of travel routes or their mobility dynamics. Considering infrastructure-based networks, the information exchange depends on the availability of the network infrastructure and the quality of the communication links. Specifically in urban areas, today's 4G and 5G networks deploy small cells of high capacity, which do not provide ubiquitous cellular coverage due to their small range, signal blocking, etc. Therefore, the accurate modeling of the network infrastructure and its integration in simulation scenarios in microscopic traffic simulation software is gaining relevance. Unlike traffic infrastructure, such as traffic lights, the simulation of a cellular network infrastructure is not natively supported in SUMO. Instead, the protocols, functions and entities of the communication system with the physical wireless transmission are modeled in a dedicated and specialized network simulator that is coupled with SUMO. The disadvantage of this approach is that the simulated SUMO entities, typically vehicles, are not aware which portions of the roads are covered by wireless cells and what quality the wireless communication links have. In this paper, we propose a method for modeling the cellular infrastructure in SUMO that introduces a cellular coverage layer to SUMO. This layer models cell sites in a regular hexagonal grid, where each site is served by a base station. Following commonly accepted guidelines for the evaluation of cellular communication system, the method facilitates standardized and realistic modeling of the cellular coverage, including cell sites, antenna characteristics, cell association and handover. In order to ease the applicability of the method, we describe the work flow to create cell sites. As a representative case, we have applied the method to InTAS, the SUMO Ingolstadt traffic scenario and applied real data for the cellular infrastructure. We validate the approach by simulating a Cellular V2X system with sidelink connectivity in an urban macro cell environment by coupling SUMO enhanced by the proposed connectivity sublayer with ARTERY-C, a network simulator for Cellular V2X. As a proof-of-concept, we present a signal-to-interference noise ratio (SINR) coverage map and further evaluate the impact of different types of interference. We also demonstrate the effect of advanced features of cellular networks such as inter-cell interference coordination (ICIC) and sidelink communication modes of Cellular V2X with dynamic switching between the in-coverage and out-of-coverage mode.}, language = {en} } @inproceedings{MaksimovskiFacchi2024, author = {Maksimovski, Daniel and Facchi, Christian}, title = {Decentralized V2X Maneuver Sharing and Coordination Message for Cooperative Driving: Analysis in Mixed Traffic}, booktitle = {2023 IEEE 26th International Conference on Intelligent Transportation Systems (ITSC)}, publisher = {IEEE}, address = {Piscataway}, isbn = {979-8-3503-9946-2}, doi = {https://doi.org/10.1109/ITSC57777.2023.10421976}, pages = {5182 -- 5189}, year = {2024}, language = {en} } @article{DeloozVinelFestag2023, author = {Delooz, Quentin and Vinel, Alexey and Festag, Andreas}, title = {Optimizing the channel resource usage for sensor data sharing with V2X communications}, volume = {71}, journal = {at - Automatisierungstechnik}, number = {4}, publisher = {De Gruyter}, address = {Berlin}, issn = {2196-677X}, doi = {https://doi.org/10.1515/auto-2022-0162}, pages = {311 -- 317}, year = {2023}, language = {en} } @article{FrankeSchwabBurgeretal.2021, author = {Franke, Florian and Schwab, Michael and Burger, Uli and H{\"u}hne, Christian}, title = {An analytical model to determine the impact force of drone strikes}, volume = {13}, journal = {CEAS Aeronautical Journal}, number = {1}, publisher = {Springer}, address = {Wien}, issn = {1869-5590}, doi = {https://doi.org/10.1007/s13272-021-00552-4}, pages = {69 -- 84}, year = {2021}, abstract = {In addition to the well-known threats of bird and hail strikes, small unmanned aerial vehicles (sUAV) pose a new threat to manned aviation. Determining the severity of collisions between sUAVs and aircraft structures is essential for the safe use and integration of drones in airspace. A generic analytical calculation model needs to be developed to supplement the existing test and simulation data. This paper presents an analytic model for drone collisions with perpendicular and inclined targets. The targets have a rigid or elastic material behavior. The aircraft impact model, which is used for the design of nuclear reactor structures, is transferred and adjusted for sUAV impacts to calculate the impact force. A mass- and a burst load distribution are needed as input parameters. Both distributions are determined for an sUAV design depending on the flight direction. Compared to previous calculations, the new approach is to consider a moving target structure, which produces more realistic results. We compare the calculation results with simulation data from sUAV collisions with a commercial airliner windshield from the literature. The calculations show plausible results and a good agreement with literature data. Subsequently, the influence of the input parameters on the impact force is investigated. We see that spring stiffness, target mass, burst load distribution and damping have minor influence on the overall impact force. The impact velocity, mass distribution and flight orientation on the other hand have a major influence on the impact force. Further tests are needed to validate the impact model.}, language = {en} } @inproceedings{HegdeLoboFestag2022, author = {Hegde, Anupama and Lobo, Silas and Festag, Andreas}, title = {Cellular-V2X for Vulnerable Road User Protection in Cooperative ITS}, booktitle = {2022 18th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-6654-6975-3}, issn = {2160-4894}, doi = {https://doi.org/10.1109/WiMob55322.2022.9941707}, pages = {118 -- 123}, year = {2022}, language = {en} } @article{ObermaierRieblAlBayattietal.2021, author = {Obermaier, Christina and Riebl, Raphael and Al-Bayatti, Ali H. and Khan, Sarmadullah and Facchi, Christian}, title = {Measuring the Realtime Capability of Parallel-Discrete-Event-Simulations}, volume = {10}, pages = {636}, journal = {Electronics}, number = {6}, publisher = {MDPI}, address = {Basel}, issn = {2079-9292}, doi = {https://doi.org/10.3390/electronics10060636}, year = {2021}, abstract = {Speeding up Discrete Event Simulations (DESs) is a broad research field. Promising Parallel Discrete Event Simulation (PDES) approaches with optimistic and conservative synchronisation schemes have emerged throughout the years. However, in the area of real-time simulation, PDESs are rarely considered. This is caused by the complex problem of fitting parallel executed DES models to a real-time clock. Hence, this paper gives an extensive review of existing conservative and optimistic synchronisation schemes for PDESs. It introduces a metric to compare their real-time capabilities to determine whether they can be used for soft or firm real-time simulation. Examples are given on how to apply this metric to evaluate PDESs using synthetic and real-world examples. The results of the investigation reveal that no final answer can be given if PDESs can be used for soft or firm real-time simulation as they are. However, boundary conditions were defined, which allow a use-case specific evaluation of the real-time capabilities of a certain parallel executed DES. Using this in-depth knowledge and can lead to predictability of the real-time behaviour of a simulation run.}, language = {en} } @inproceedings{SongZhouLakshminarasimhanetal.2022, author = {Song, Rui and Zhou, Liguo and Lakshminarasimhan, Venkatnarayanan and Festag, Andreas and Knoll, Alois}, title = {Federated Learning Framework Coping with Hierarchical Heterogeneity in Cooperative ITS}, booktitle = {2022 IEEE 25th International Conference on Intelligent Transportation Systems (ITSC)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-6654-6880-0}, pages = {3502 -- 3508}, year = {2022}, language = {en} } @inproceedings{FestagUdupaGarciaetal.2021, author = {Festag, Andreas and Udupa, Shrivatsa and Garcia, Lourdes and Wellens, Ralf and Hecht, Matthias and Ulfig, Pierre}, title = {End-to-End Performance Measurements of Drone Communications in 5G Cellular Networks}, booktitle = {2021 IEEE 94th Vehicular Technology Conference (VTC2021-Fall): Proceedings}, publisher = {IEEE}, address = {Piscataway (NJ)}, isbn = {978-1-6654-1368-8}, issn = {2577-2465}, doi = {https://doi.org/10.1109/VTC2021-Fall52928.2021.9625429}, year = {2021}, language = {en} } @article{SongZhouLyuetal.2023, author = {Song, Rui and Zhou, Liguo and Lyu, Lingjuan and Festag, Andreas and Knoll, Alois}, title = {ResFed: Communication-Efficient Federated Learning With Deep Compressed Residuals}, volume = {11}, journal = {IEEE Internet of Things Journal}, number = {6}, publisher = {IEEE}, address = {New York}, issn = {2327-4662}, doi = {https://doi.org/10.1109/JIOT.2023.3324079}, pages = {9458 -- 9472}, year = {2023}, abstract = {Federated learning allows for cooperative training among distributed clients by sharing their locally learned model parameters, such as weights or gradients. However, as model size increases, the communication bandwidth required for deployment in wireless networks becomes a bottleneck. To address this, we propose a residual-based federated learning framework (ResFed) that transmits residuals instead of gradients or weights in networks. By predicting model updates at both clients and the server, residuals are calculated as the difference between updated and predicted models and contain more dense information than weights or gradients. We find that the residuals are less sensitive to an increasing compression ratio than other parameters, and hence use lossy compression techniques on residuals to improve communication efficiency for training in federated settings. With the same compression ratio, ResFed outperforms current methods (weight- or gradient-based federated learning) by over 1.4× on federated data sets, including MNIST, FashionMNIST, SVHN, CIFAR-10, CIFAR-100, and FEMNIST, in client-to-server communication, and can also be applied to reduce communication costs for server-to-client communication.}, language = {en} } @misc{OPUS4-3105, title = {International Journal on Advances in Security. 15(1\&2)}, editor = {Hof, Hans-Joachim and Gersbeck-Schierholz, Birgit}, publisher = {IARIA}, issn = {1942-2636}, url = {http://www.iariajournals.org/security/tocv15n12.html}, year = {2022}, language = {en} } @article{RufinoJuniorRivaSanseverinoGalloetal.2023, author = {Rufino J{\´u}nior, Carlos Ant{\^o}nio and Riva Sanseverino, Eleonora and Gallo, Pierluigi and Koch, Daniel and Kotak, Yash and Schweiger, Hans-Georg and Zanin, Hudson}, title = {Towards a business model for second-life batteries - barriers, opportunities, uncertainties, and technologies}, volume = {2023}, journal = {Journal of Energy Chemistry}, number = {78}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2096-885X}, doi = {https://doi.org/10.1016/j.jechem.2022.12.019}, pages = {507 -- 525}, year = {2023}, language = {en} } @article{KostetzerNeblStichetal.2020, author = {Kostetzer, Lucas and Nebl, Christoph and Stich, Michael and Bund, Andreas and Schweiger, Hans-Georg}, title = {Physics-Based Modeling and Parameter Identification for Lithium Ion Batteries Under High Current Discharge Conditions}, volume = {167}, pages = {140549}, journal = {Journal of the Electrochemical Society}, number = {14}, publisher = {IOP Publishing}, address = {Bristol}, issn = {1945-7111}, doi = {https://doi.org/10.1149/1945-7111/abc726}, year = {2020}, language = {en} } @book{OPUS4-3108, title = {SECURWARE 2021: The Fifteenth International Conference on Emerging Security Information, Systems and Technologies}, editor = {Hof, Hans-Joachim and Popescu, Manuela and Fongen, Anders}, publisher = {IARIA}, isbn = {978-1-61208-919-5}, issn = {2162-2116}, pages = {93}, year = {2021}, language = {en} } @inproceedings{BarbosadaSilvaLoboFernandezetal.2024, author = {Barbosa da Silva, Leonardo and Lobo, Silas and Fern{\´a}ndez, Evelio and Facchi, Christian}, title = {Is the Right Bounding Box of a VRU Cluster in V2X Communication? How to Form a Good Shape?}, booktitle = {Vehits 2024: 10th International Conference on Vehicle Technology and Intelligent Transport Systems Proceedings}, editor = {Vinel, Alexey and Berns, Karsten and Ploeg, Jeroen and Gusikhin, Oleg}, publisher = {SciTePress}, address = {Set{\´u}bal}, doi = {https://doi.org/10.5220/0012699100003702}, pages = {144 -- 155}, year = {2024}, abstract = {Among the possible traffic members on a Vehicle-to-Everything network, the term Vulnerable Road User (VRU) is assigned e.g. to pedestrians and cyclists. The VRU Awareness Message (VAM) is used by VRUs to inform other users of their presence and ensure they are perceived in a traffic system. Since the number of VRUs in crowded areas might be very high, the over-the-air traffic might be overloaded. To reduce channel overload, VAMs offer a clustering feature in which VRUs with similar kinematics and positions can group themselves so that only one device transmits messages. The VRU Basic Service specification describes the cluster as a bounding box that must cover all its members using a geometric shape so that other vehicles in the vicinity can avoid colliding with the contained VRUs. This paper contributes to the standardization effort by introducing a data structure, the Cluster Map, for the clustering in the VRU Basic Service. Furthermore, this work is the first to suggest strategies for forming bounding box shapes. Simulation results show that each of the geometry types is useful in different situations, thus further research on the topic is advised.}, language = {en} } @article{SongXuFestagetal.2023, author = {Song, Rui and Xu, Runsheng and Festag, Andreas and Ma, Jiaqi and Knoll, Alois}, title = {FedBEVT: Federated Learning Bird's Eye View Perception Transformer in Road Traffic Systems}, volume = {9}, journal = {IEEE Transactions on Intelligent Vehicles}, number = {1}, publisher = {IEEE}, address = {New York}, issn = {2379-8904}, doi = {https://doi.org/10.1109/TIV.2023.3310674}, pages = {958 -- 969}, year = {2023}, abstract = {Bird's eye view (BEV) perception is becoming increasingly important in the field of autonomous driving. It uses multi-view camera data to learn a transformer model that directly projects the perception of the road environment onto the BEV perspective. However, training a transformer model often requires a large amount of data, and as camera data for road traffic are often private, they are typically not shared. Federated learning offers a solution that enables clients to collaborate and train models without exchanging data but model parameters. In this paper, we introduce FedBEVT, a federated transformer learning approach for BEV perception. In order to address two common data heterogeneity issues in FedBEVT: (i) diverse sensor poses, and (ii) varying sensor numbers in perception systems, we propose two approaches - Federated Learning with Camera-Attentive Personalization (FedCaP) and Adaptive Multi-Camera Masking (AMCM), respectively. To evaluate our method in real-world settings, we create a dataset consisting of four typical federated use cases. Our findings suggest that FedBEVT outperforms the baseline approaches in all four use cases, demonstrating the potential of our approach for improving BEV perception in autonomous driving.}, language = {en} } @inproceedings{GomezBuquerinCorbettHof2021, author = {Gomez Buquerin, Kevin and Corbett, Christopher and Hof, Hans-Joachim}, title = {Structured methodology and survey to evaluate data completeness in automotive digital forensics}, booktitle = {19th escar Europe: The World's Leading Automotive Cyber Security Conference}, publisher = {Ruhr-Universit{\"a}t Bochum}, address = {Bochum}, doi = {https://doi.org/10.13154/294-8351}, pages = {52 -- 67}, year = {2021}, language = {en} } @article{WettLampeHassetal.2024, author = {Wett, Christopher and Lampe, J{\"o}rg and Haß, Jan and Seeger, Thomas and Turan, Bugra}, title = {On the State of Usability for Lithium-Ion Batteries}, volume = {10}, pages = {57}, journal = {Batteries}, number = {2}, publisher = {MDPI}, address = {Basel}, issn = {2313-0105}, doi = {https://doi.org/10.3390/batteries10020057}, year = {2024}, abstract = {Lithium-ion batteries are well established as traction batteries for electric vehicles. This has led to a growing market for second-life batteries that can be used in applications like home energy storage systems. Moreover, the recyclability and safe handling of aged or damaged cells and packs has become more important. While there are several indicators, like state of health (SOH), state of power (SOP), or state of safety (SOS), which describe the state of a battery before its defined end of life (EOL), there is no consistent classification methodology by which to describe the usability of a cell or pack after its EOL is reached. The proposed state of usability (SOU) provides a new indicator that accounts for the usability for second life, recyclability, and possible required safety handling of a lithium-ion battery after its first intended life cycle. This work presents a decision tree method, which in turn leads to five discrete usability levels enabling a fast and rough determination of the SOU for practical use. Further, a calculation methodology for reasonable continuous regions of the SOU is proposed. Both methods are based on a literature-based rating of all of the relevant defect and aging mechanisms displayed in a risk matrix. Finally, some experimental methods that can be used for SOU determination are proposed. The developed methodology and the hands-on approach using a decision tree are well-suited for real world application in recycling companies and battery test laboratories.}, language = {en} } @article{DeloozFestagVinel2021, author = {Delooz, Quentin and Festag, Andreas and Vinel, Alexey}, title = {Congestion Aware Objects Filtering for Collective Perception}, volume = {80}, journal = {Electronic Communications of the EASST}, publisher = {TU Berlin}, address = {Berlin}, issn = {1863-2122}, doi = {http://dx.doi.org/10.14279/tuj.eceasst.80.1160}, year = {2021}, abstract = {This paper addresses collective perception for connected and automated driving. It proposes the adaptation of filtering rules based on the currently available channel resources, referred to as Enhanced DCC-Aware Filtering (EDAF).}, language = {en} } @article{FloresFernandezSanchezMoralesBotschetal.2022, author = {Flores Fern{\´a}ndez, Alberto and S{\´a}nchez Morales, Eduardo and Botsch, Michael and Facchi, Christian and Garc{\´i}a Higuera, Andr{\´e}s}, title = {Generation of Correction Data for Autonomous Driving by Means of Machine Learning and On-Board Diagnostics}, volume = {23}, pages = {159}, journal = {Sensors}, number = {1}, publisher = {MDPI}, address = {Basel}, issn = {1424-8220}, doi = {https://doi.org/10.3390/s23010159}, year = {2022}, abstract = {A highly accurate reference vehicle state is a requisite for the evaluation and validation of Autonomous Driving (AD) and Advanced Driver Assistance Systems (ADASs). This highly accurate vehicle state is usually obtained by means of Inertial Navigation Systems (INSs) that obtain position, velocity, and Course Over Ground (COG) correction data from Satellite Navigation (SatNav). However, SatNav is not always available, as is the case of roofed places, such as parking structures, tunnels, or urban canyons. This leads to a degradation over time of the estimated vehicle state. In the present paper, a methodology is proposed that consists on the use of a Machine Learning (ML)-method (Transformer Neural Network—TNN) with the objective of generating highly accurate velocity correction data from On-Board Diagnostics (OBD) data. The TNN obtains OBD data as input and measurements from state-of-the-art reference sensors as a learning target. The results show that the TNN is able to infer the velocity over ground with a Mean Absolute Error (MAE) of 0.167 kmh (0.046 ms) when a database of 3,428,099 OBD measurements is considered. The accuracy decreases to 0.863 kmh (0.24 ms) when only 5000 OBD measurements are used. Given that the obtained accuracy closely resembles that of state-of-the-art reference sensors, it allows INSs to be provided with accurate velocity correction data. An inference time of less than 40 ms for the generation of new correction data is achieved, which suggests the possibility of online implementation. This supports a highly accurate estimation of the vehicle state for the evaluation and validation of AD and ADAS, even in SatNav-deprived environments.}, language = {en} } @article{DeloozWilleckeGarlichsetal.2022, author = {Delooz, Quentin and Willecke, Alexander and Garlichs, Keno and Hagau, Andreas-Christian and Wolf, Lars and Vinel, Alexey and Festag, Andreas}, title = {Analysis and Evaluation of Information Redundancy Mitigation for V2X Collective Perception}, volume = {10}, journal = {IEEE Access}, publisher = {IEEE}, address = {Piscataway}, issn = {2169-3536}, doi = {https://doi.org/10.1109/ACCESS.2022.3170029}, pages = {47076 -- 47093}, year = {2022}, abstract = {Sensor data sharing enables vehicles to exchange locally perceived sensor data among each other and with the roadside infrastructure to increase their environmental awareness. It is commonly regarded as a next-generation vehicular communication service beyond the exchange of highly aggregated messages in the first generation. The approach is being considered in the European standardization process, where it relies on the exchange of locally detected objects representing anything safety-relevant, such as other vehicles or pedestrians, in periodically broadcasted messages to vehicles in direct communication range. Objects filtering methods for inclusion in a message are necessary to avoid overloading a channel and provoking unnecessary data processing. Initial studies provided in a pre-standardization report about sensor data sharing elaborated a first set of rules to filter objects based on their characteristics, such as their dynamics or type. However, these rules still lack the consideration of information received by other stations to operate. Specifically, to address the problem of information redundancy, several rules have been proposed, but their performance has not been evaluated yet comprehensively. In the present work, the rules are further analyzed, assessed, and compared. Functional and operational requirements are investigated. A performance evaluation is realized by discrete-event simulations in a scenario for a representative city with realistic vehicle densities and mobility patterns. A score and other redundancy-level metrics are elaborated to ease the evaluation and comparison of the filtering rules. Finally, improvements and future works to the filtering methods are proposed.}, language = {en} } @article{FrankeBurgerHuehne2023, author = {Franke, Florian and Burger, Uli and H{\"u}hne, Christian}, title = {A novel reduced order model for drone impacts with aircraft structures}, volume = {14}, journal = {CEAS Aeronautical Journal}, number = {2}, publisher = {Springer}, address = {Wien}, issn = {1869-5590}, doi = {https://doi.org/10.1007/s13272-023-00646-1}, pages = {381 -- 412}, year = {2023}, abstract = {Small unmanned aerial vehicles are a threat for manned aviation. Their increased use by hobby pilots and within the commercial sector has been accompanied by an increase in incidents involving manned aircraft. The problem is that current aircraft structures are designed to resist collisions with birds. They are not designed to withstand drone impacts. The composition of drones differs significantly from previously known load cases. Drones consist of several components with various materials. This means, that there is no analytic model to determine the impact force of such drone strikes with aircraft structures. Within this work, a novel reduced order model for drone impacts is developed. It is validated with high velocity impact test data and explicit finite element simulations. The impact of fragmenting components of the drone are modelled with the aircraft impact model. The impact of non-fragmenting components like motors are described with a spring-mass model. The results show that the approach of superimposing a spring-mass model with the aircraft impact model leads to good results. In case of a rigid target only minor deviations occur within the validity range of the model. Damage and degradation of the target is not included in the model what leads to larger deviations in case of an impact with deformable structures. Nevertheless, the model is very well suited for rapid load estimation and can qualitatively reproduce contact force curves. It can be used for preliminary design of aircraft structures without conducting time and cost intensive tests and simulations.}, language = {en} } @article{WoehrlGeisbauerNebletal.2021, author = {W{\"o}hrl, Katharina and Geisbauer, Christian and Nebl, Christoph and Lott, Susanne and Schweiger, Hans-Georg}, title = {Crashed Electric Vehicle Handling and Recommendations}, volume = {14}, pages = {1040}, journal = {Energies}, subtitle = {State of the Art in Germany}, number = {4}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {https://doi.org/10.3390/en14041040}, year = {2021}, abstract = {In the near future, electric powered vehicles will represent a major part of the road traffic. Accordingly, there will be a natural increase of accidents involving electric vehicles. There are not many cases of such accidents yet and therefore the experience and correct handling are still partially open points for the involved parties, such as the rescue services for example. The aim of this work is to provide a complete overview of the accident handling sequence in Germany, starting with the damaged vehicle on site and moving on to the risks and challenges for the stakeholders, such as transport and recycling companies. Arising from the developed overview, a handling recommendation for yet undiscussed points is given. Especially, different extinguishing and deactivation methods are compared and discussed. Due to a lack of a common live-feed from battery data on site, other criteria have to be taken into account to assess the state of the battery. The wrecked vehicle—including the high voltage system—needs to be in a definite safe state at the handover to a towing service. Depending on the case, different options for securing the vehicle will be considered in this work.}, language = {en} } @article{KotakMarchanteFernandezCanalsCasalsetal.2021, author = {Kotak, Yash and Marchante Fern{\´a}ndez, Carlos and Canals Casals, Lluc and Kotak, Bhavya and Koch, Daniel and Geisbauer, Christian and Trilla, Llu{\´i}s and G{\´o}mez-Nu{\~n}ez, Alberto and Schweiger, Hans-Georg}, title = {End of Electric Vehicle Batteries}, volume = {14}, pages = {2217}, journal = {Energies}, subtitle = {Reuse vs. Recycle}, number = {8}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {https://doi.org/10.3390/en14082217}, year = {2021}, abstract = {It is a fact that electric vehicles (EVs) are beneficial for climate protection. However, the current challenge is to decide on whether to reuse an EV battery or to recycle it after its first use. This paper theoretically investigates these areas i.e., recycle and reuse. It was found that there are several commercially used recycling processes and also some are under research to regain maximum possible materials and quantity. The concept of reusing (second life) of the battery is promising because, at the end of the first life, batteries from EVs can be used in several applications such as storing energy generated from renewable sources to support the government grid. However, the cost and life-cycle analysis (LCA) demonstrated that there are several aspects involved in battery reuse applications. Henceforth, one LCA generalised method cannot provide an optimal approach for all cases. It is important to have a detailed study on each of the battery reusing applications. Until then, it is safe to say that reusing the battery is a good option as it would give some time to recycling companies to develop cost and energy-efficient methods.}, language = {en} } @article{GeisbauerWoehrlKochetal.2021, author = {Geisbauer, Christian and W{\"o}hrl, Katharina and Koch, Daniel and Wilhelm, Gudrun and Schneider, Gerhard and Schweiger, Hans-Georg}, title = {Comparative Study on the Calendar Aging Behavior of Six Different Lithium-Ion Cell Chemistries in Terms of Parameter Variation}, volume = {14}, pages = {3358}, journal = {Energies}, number = {11}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {https://doi.org/10.3390/en14113358}, year = {2021}, abstract = {The degradation of lithium-ion cells is an important aspect, not only for quality management, but also for the customer of the application like, e.g., scooters or electric vehicles. During the lifetime of the system, the overall health on the battery plays a key role in its depreciation. Therefore, it is necessary to monitor the health of the battery during operation, i.e., cycle life, but also during stationary conditions, i.e., calendar aging. In this work, the degradation due to calendar aging is analyzed for six different cell chemistries in terms of capacity degradation and impedance increase and their performance are being compared. In a new proposed metric, the relative deviations between various cells with the exact identical aging history are being analyzed for their degradation effects and their differences, which stands out in comparison to similar research. The capacity loss was found to be most drastic at 60 °C and at higher storage voltages, even for titanate-oxide cells. LiNiMnCoO2 (NMC), LiNiCoAlO2 (NCA) and Li2TiO3 (LTO) cells at 60 °C showed the most drastic capacity decrease. NMC and NCA cells at 60 °C and highest storage voltage did not show any open circuit voltage, as their current interrupt mechanism triggered. The effect of aging shows no uniform impact on the changes in the capacity variance when comparing different aging conditions, with respect to the evaluated standard deviation for all cells. The focus of this work was on the calendar aging effect and may be supplemented in a second study for cyclic aging.}, language = {en} } @article{AhlbergTidbladEdstroemHernandezetal.2021, author = {Ahlberg Tidblad, Annika and Edstr{\"o}m, Kristina and Hern{\´a}ndez, Guiomar and de Meatza, Iratxe and Landa-Medrano, Imanol and Jacas Biendicho, Jordi and Trilla, Llu{\´i}s and Buysse, Maarten and Ierides, Marcos and Perez Horno, Beatriz and Kotak, Yash and Schweiger, Hans-Georg and Koch, Daniel and Kotak, Bhavya}, title = {Future Material Developments for Electric Vehicle Battery Cells Answering Growing Demands from an End-User Perspective}, volume = {14}, pages = {4223}, journal = {Energies}, number = {14}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {https://doi.org/10.3390/en14144223}, year = {2021}, abstract = {Nowadays, batteries for electric vehicles are expected to have a high energy density, allow fast charging and maintain long cycle life, while providing affordable traction, and complying with stringent safety and environmental standards. Extensive research on novel materials at cell level is hence needed for the continuous improvement of the batteries coupled towards achieving these requirements. This article firstly delves into future developments in electric vehicles from a technology perspective, and the perspective of changing end-user demands. After these end-user needs are defined, their translation into future battery requirements is described. A detailed review of expected material developments follows, to address these dynamic and changing needs. Developments on anodes, cathodes, electrolyte and cell level will be discussed. Finally, a special section will discuss the safety aspects with these increasing end-user demands and how to overcome these issues.}, language = {en} } @article{GomezBuquerinCorbettHof2021, author = {Gomez Buquerin, Kevin and Corbett, Christopher and Hof, Hans-Joachim}, title = {A generalized approach to automotive forensics}, volume = {2021}, pages = {301111}, journal = {Forensic Science International: Digital Investigation}, number = {36, Supplement}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2666-2817}, doi = {https://doi.org/10.1016/j.fsidi.2021.301111}, year = {2021}, abstract = {In the past years, software became an essential topic in modern vehicles, e.g., with the rise of more and more complex driver assistance systems. The advent of automated driving will drive this trend even further. Today, accident investigation, as well as warranty claim analysis, need to take into consideration an analysis of the rapidly increasing proportion of software and security based implementations as part of modern vehicles, the so-called digital forensics. This paper evaluates the general feasibility of digital forensics on a state-of-the-art vehicle. To do so, we analyzed current digital forensics techniques on a state-of-the-art vehicle to constitute gaps in the automotive forensics process used on in-vehicle systems. We present a general process for automotive forensics to close existing gaps and implemented it on a state-of-the-art vehicle in an in-vehicle device manipulation scenario. The implementation uses the on-board diagnostics interface, the diagnostics over internet protocol, as well as the unified diagnostic services for communication. Our implementation requires automotive Ethernet at the diagnostic interface. Our research shows future directions for efficient automotive forensic as well as the exemplary feasibility of automotive forensic analysis on state-of-the-art vehicles without the need for additional invehicle components such as intrusion detection systems or event data recorders.}, language = {en} } @inproceedings{deMeerWaedtRennochetal.2021, author = {de Meer, Jan and Waedt, Karl and Rennoch, Axel and Hof, Hans-Joachim}, title = {The 5th GI/ACM Workshop 2020 scope and draft programme on standardization of secure and safe smart manufacturing systems with respect to IEC 62443 IACS}, volume = {2021}, booktitle = {Lecture Notes in Informatics (LNI): Proceedings}, number = {Volume P-307}, publisher = {Gesellschaft f{\"u}r Informatik}, address = {Bonn}, isbn = {978-3-88579-701-2}, issn = {1617-5468}, doi = {https://doi.org/10.18420/inf2020_26}, pages = {283 -- 287}, year = {2021}, abstract = {The 5th GI/ACM Workshop Programme on Standardization of Secure and Safe Production within Industrial Automation and Control Systems (IACS) took place virtually at September 28, 2020 at the Karlsruhe Institute of Technology (KIT) that hosted the 50th GI's yearly assembly (GI Informatik 2020 Jahrestagung)ȷ}, language = {en} } @article{FloresFernandezWurstSanchezMoralesetal.2022, author = {Flores Fern{\´a}ndez, Alberto and Wurst, Jonas and S{\´a}nchez Morales, Eduardo and Botsch, Michael and Facchi, Christian and Garc{\´i}a Higuera, Andr{\´e}s}, title = {Probabilistic Traffic Motion Labeling for Multi-Modal Vehicle Route Prediction}, volume = {22}, pages = {4498}, journal = {Sensors}, number = {12}, publisher = {MDPI}, address = {Basel}, issn = {1424-8220}, doi = {https://doi.org/10.3390/s22124498}, year = {2022}, abstract = {The prediction of the motion of traffic participants is a crucial aspect for the research and development of Automated Driving Systems (ADSs). Recent approaches are based on multi-modal motion prediction, which requires the assignment of a probability score to each of the multiple predicted motion hypotheses. However, there is a lack of ground truth for this probability score in the existing datasets. This implies that current Machine Learning (ML) models evaluate the multiple predictions by comparing them with the single real trajectory labeled in the dataset. In this work, a novel data-based method named Probabilistic Traffic Motion Labeling (PROMOTING) is introduced in order to (a) generate probable future routes and (b) estimate their probabilities. PROMOTING is presented with the focus on urban intersections. The generation of probable future routes is (a) based on a real traffic dataset and consists of two steps: first, a clustering of intersections with similar road topology, and second, a clustering of similar routes that are driven in each cluster from the first step. The estimation of the route probabilities is (b) based on a frequentist approach that considers how traffic participants will move in the future given their motion history. PROMOTING is evaluated with the publicly available Lyft database. The results show that PROMOTING is an appropriate approach to estimate the probabilities of the future motion of traffic participants in urban intersections. In this regard, PROMOTING can be used as a labeling approach for the generation of a labeled dataset that provides a probability score for probable future routes. Such a labeled dataset currently does not exist and would be highly valuable for ML approaches with the task of multi-modal motion prediction. The code is made open source.}, language = {en} } @article{HegdeSongFestag2023, author = {Hegde, Anupama and Song, Rui and Festag, Andreas}, title = {Radio Resource Allocation in 5G-NR V2X: A Multi-Agent Actor-Critic Based Approach}, volume = {11}, journal = {IEEE Access}, publisher = {IEEE}, address = {Piscataway}, issn = {2169-3536}, doi = {https://doi.org/10.1109/ACCESS.2023.3305267}, pages = {87225 -- 87244}, year = {2023}, abstract = {The efficiency of radio resource allocation and scheduling procedures in Cellular Vehicle-to-X (Cellular V2X) communication networks directly affects link quality in terms of latency and reliability. However, owing to the continuous movement of vehicles, it is impossible to have a centralized coordinating unit at all times to manage the allocation of radio resources. In the unmanaged mode of the fifth generation new radio (5G-NR) V2X, the sensing-based semi-persistent scheduling (SB-SPS) loses its effectiveness when V2X data messages become aperiodic with varying data sizes. This leads to misinformed resource allocation decisions among vehicles and frequent resource collisions. To improve resource selection, this study formulates the Cellular V2X communication network as a decentralized multi-agent networked markov decision process (MDP) where each vehicle agent executes an actor-critic-based radio resource scheduler. Developing further the actor-critic methodology for the radio resource allocation problem in Cellular V2X, two variants are derived: independent actor-critic (IAC) and shared experience actor-critic (SEAC). Results from simulation studies indicate that the actor-critic schedulers improve reliability, achieving a 15-20\% higher probability of reception under high vehicular density scenarios with aperiodic traffic patterns.}, language = {en} } @unpublished{BazziSepulcreDeloozetal.2023, author = {Bazzi, Alessandro and Sepulcre, Miguel and Delooz, Quentin and Festag, Andreas and Vogt, Jonas and Wieker, Horst and Berens, Friedbert and Spaanderman, Paul}, title = {Multi-Channel Operation for the Release 2 of ETSI Cooperative Intelligent Transport Systems}, publisher = {arXiv}, address = {Ithaca}, doi = {https://doi.org/10.48550/arXiv.2305.19863}, year = {2023}, abstract = {Vehicles and road infrastructure are starting to be equipped with vehicle-to-everything (V2X) communication solutions to increase road safety and provide new services to drivers and passengers. In Europe, the deployment is based on a set of Release 1 standards developed by ETSI to support basic use cases for cooperative intelligent transport systems (C-ITS). For them, the capacity of a single 10 MHz channel in the ITS band at 5.9 GHz is considered sufficient. At the same time, the ITS stakeholders are working towards several advanced use cases, which imply a significant increment of data traffic and the need for multiple channels. To address this issue, ETSI has recently standardized a new multi-channel operation (MCO) concept for flexible, efficient, and future-proof use of multiple channels. This new concept is defined in a set of new specifications that represent the foundation for the future releases of C-ITS standards. The present paper provides a comprehensive review of the new set of specifications, describing the main entities extending the C-ITS architecture at the different layers of the protocol stack, In addition, the paper provides representative examples that describe how these MCO standards will be used in the future and discusses some of the main open issues arising. The review and analysis of this paper facilitate the understanding and motivation of the new set of Release 2 ETSI specifications for MCO and the identification of new research opportunities.}, language = {en} } @article{KochSchweiger2022, author = {Koch, Daniel and Schweiger, Hans-Georg}, title = {Possibilities for a Quick Onsite Safety-State Assessment of Stand-Alone Lithium-Ion Batteries}, volume = {8}, pages = {213}, journal = {Batteries}, number = {11}, publisher = {MDPI}, address = {Basel}, issn = {2313-0105}, doi = {https://doi.org/10.3390/batteries8110213}, year = {2022}, abstract = {Electric vehicles' high-voltage lithium-ion batteries are complex systems and can be sources of several hazards for interacting people. Sophisticated battery management systems (BMS) therefore constantly monitor their characteristics and varying states, to keep the battery within desired operational conditions and to mitigate safety risks as well as excessive degradation. However, there can be several situations where the battery is not in normal operation (e.g., a stand-alone battery) and a fully functional BMS monitoring function is not available. When necessary to interact with the system, its safety state must be deduced to ensure the safety of interactors. This can be a challenging task depending on a situation's characteristics (time pressure, technical knowledge of involved people). Thus, this article discusses how the safety state of electric vehicle batteries can be evaluated quickly even by untrained people. To develop a solution, different scenarios, which require a battery's state assessment, and the options for collecting relevant information are motivated and discussed, respectively. Finally, a mobile interface that can evaluate and display the safety state by using BMS-internal data is described and demonstrated.}, language = {en} } @article{StegerKroghMeegahapolaetal.2022, author = {Steger, Fabian and Krogh, Jonathan and Meegahapola, Lasantha and Schweiger, Hans-Georg}, title = {Calculating Available Charge and Energy of Lithium-Ion Cells Based on OCV and Internal Resistance}, volume = {15}, pages = {7902}, journal = {Energies}, number = {21}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {https://doi.org/10.3390/en15217902}, year = {2022}, abstract = {The design and operation of performant and safe electric vehicles depend on precise knowledge of the behavior of their electrochemical energy storage systems. The performance of the battery management systems often relies on the discrete-time battery models, which can correctly emulate the battery characteristics. Among the available methods, electric circuit-based equations have shown to be especially useful in describing the electrical characteristics of batteries. To overcome the existing drawbacks, such as discrete-time simulations for parameter estimation and the usage of look-up tables, a set of equations has been developed in this study that solely relies on the open-circuit voltage and the internal resistance of a battery. The parameters can be obtained from typical cell datasheets or can be easily extracted via standard measurements. The proposed equations allow for the direct analytical determination of available discharge capacity and the available energy content depending on the discharge current, as well as the Peukert exponent. The fidelity of the proposed system was validated experimentally using 18650 NMC and LFP lithium-ion cells, and the results are in close agreement with the datasheet.}, language = {en} } @unpublished{SongLiangCaoetal.2024, author = {Song, Rui and Liang, Chenwei and Cao, Hu and Yan, Zhiran and Zimmer, Walter and Gross, Markus and Festag, Andreas and Knoll, Alois}, title = {Collaborative Semantic Occupancy Prediction with Hybrid Feature Fusion in Connected Automated Vehicles}, publisher = {arXiv}, address = {Ithaca}, doi = {https://doi.org/10.48550/arXiv.2402.07635}, year = {2024}, abstract = {Collaborative perception in automated vehicles leverages the exchange of information between agents, aiming to elevate perception results. Previous camera-based collaborative 3D perception methods typically employ 3D bounding boxes or bird's eye views as representations of the environment. However, these approaches fall short in offering a comprehensive 3D environmental prediction. To bridge this gap, we introduce the first method for collaborative 3D semantic occupancy prediction. Particularly, it improves local 3D semantic occupancy predictions by hybrid fusion of (i) semantic and occupancy task features, and (ii) compressed orthogonal attention features shared between vehicles. Additionally, due to the lack of a collaborative perception dataset designed for semantic occupancy prediction, we augment a current collaborative perception dataset to include 3D collaborative semantic occupancy labels for a more robust evaluation. The experimental findings highlight that: (i) our collaborative semantic occupancy predictions excel above the results from single vehicles by over 30\%, and (ii) models anchored on semantic occupancy outpace state-of-the-art collaborative 3D detection techniques in subsequent perception applications, showcasing enhanced accuracy and enriched semantic-awareness in road environments.}, language = {en} } @article{WoehrlKotakGeisbaueretal.2023, author = {W{\"o}hrl, Katharina and Kotak, Yash and Geisbauer, Christian and Barra, S{\"o}nke and Wilhelm, Gudrun and Schneider, Gerhard and Schweiger, Hans-Georg}, title = {Analysis of Deactivation of 18,650 Lithium-Ion Cells in CaCl2, Tap Water and Demineralized Water for Different Insertion Times}, volume = {23}, pages = {3901}, journal = {Sensors}, number = {8}, publisher = {MDPI}, address = {Basel}, issn = {1424-8220}, doi = {https://doi.org/10.3390/s23083901}, year = {2023}, abstract = {The deployment of battery-powered electric vehicles in the market has created a naturally increasing need for the safe deactivation and recycling of batteries. Various deactivating methods for lithium-ion cells include electrical discharging or deactivation with liquids. Such methods are also useful for cases where the cell tabs are not accessible. In the literature analyses, different deactivation media are used, but none include the use of calcium chloride (CaCl2) salt. As compared to other media, the major advantage of this salt is that it can capture the highly reactive and hazardous molecules of Hydrofluoric acid. To analyse the actual performance of this salt in terms of practicability and safety, this experimental research aims to compare it against regular Tap Water and Demineralized Water. This will be accomplished by performing nail penetration tests on deactivated cells and comparing their residual energy against each other. Moreover, these three different media and respective cells are analysed after deactivation, i.e., based on conductivity measurements, cell mass, flame photometry, fluoride content, computer tomography and pH value. It was found that the cells deactivated in the CaCl2 solution did not show any signs of Fluoride ions, whereas cells deactivated in TW showed the emergence of Fluoride ions in the 10th week of the insertion. However, with the addition of CaCl2 in TW, the deactivation process > 48 h for TW declines to 0.5-2 h, which could be an optimal solution for real-world situations where deactivating cells at a high pace is essential.}, language = {en} } @article{ZhouSongChenetal.2023, author = {Zhou, Liguo and Song, Rui and Chen, Guang and Festag, Andreas and Knoll, Alois}, title = {Residual encoding framework to compress DNN parameters for fast transfer}, volume = {2023}, pages = {110815}, journal = {Knowledge-Based Systems}, number = {277}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1872-7409}, doi = {https://doi.org/10.1016/j.knosys.2023.110815}, year = {2023}, language = {en} } @article{RufinoJuniorRivaSanseverinoGalloetal.2022, author = {Rufino J{\´u}nior, Carlos Ant{\^o}nio and Riva Sanseverino, Eleonora and Gallo, Pierluigi and Koch, Daniel and Schweiger, Hans-Georg and Zanin, Hudson}, title = {Blockchain review for battery supply chain monitoring and battery trading}, volume = {2022}, pages = {112078}, journal = {Renewable and Sustainable Energy Reviews}, number = {157}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1879-0690}, doi = {https://doi.org/10.1016/j.rser.2022.112078}, year = {2022}, language = {en} } @inproceedings{ObermaierRieblFacchietal.2021, author = {Obermaier, Christina and Riebl, Raphael and Facchi, Christian and Al-Bayatti, Ali H. and Khan, Sarmadullah}, title = {COSIDIA: an approach for real-time parallel discrete event simulations tailored for wireless networks}, booktitle = {SIGSIM-PADS '21: Proceedings of the 2021 ACM SIGSIM Conference on Principles of Advanced Discrete Simulation}, publisher = {ACM}, address = {New York}, isbn = {978-1-4503-8296-0}, doi = {https://doi.org/10.1145/3437959.3459250}, pages = {165 -- 171}, year = {2021}, language = {en} } @article{LauschTaklaSchweiger2022, author = {Lausch, Jonas and Takla, Monir and Schweiger, Hans-Georg}, title = {Insight into crush performance comparison of composite profiles and flat plates}, volume = {2022}, pages = {109643}, journal = {Composites Part B: Engineering}, number = {233}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1359-8368}, doi = {https://doi.org/10.1016/j.compositesb.2022.109643}, year = {2022}, language = {en} } @inproceedings{NeumeierStapfFacchi2020, author = {Neumeier, Stefan and Stapf, Simon and Facchi, Christian}, title = {The visual quality of teleoperated driving scenarios}, booktitle = {2020 International Symposium on Networks, Computers and Communications (ISNCC)}, subtitle = {how good is good enough?}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-7281-5628-6}, doi = {https://doi.org/10.1109/ISNCC49221.2020.9297343}, year = {2020}, language = {en} } @inproceedings{WechBoehmSchweigeretal.2020, author = {Wech, Lothar and B{\"o}hm, Klaus and Schweiger, Hans-Georg and Paula, Daniel}, title = {Event Data Recorder (EDR) for automated vehicles}, booktitle = {SafetyWeek : Die Zukunft der Fahrzeugsicherheit}, subtitle = {Legal certainty and data privacy for all}, doi = {https://www.carhs.de/de/publikationen/product/safetyweek-2020-replay.html}, year = {2020}, language = {en} } @inproceedings{FrankeBurgerHuehne2021, author = {Franke, Florian and Burger, Uli and H{\"u}hne, Christian}, title = {Models and Methods for Drone Strike Load Predictions}, booktitle = {ICAS 2020/21 Proceedings}, publisher = {International Council of the Aeronautical Sciences (ICAS)}, address = {Bonn}, isbn = {978-3-932182-91-4}, url = {https://www.icas.org/ICAS_ARCHIVE/ICAS2020/data/preview/ICAS2020_0019.htm}, year = {2021}, language = {en} }