@misc{KarnapkeRichterWerner, author = {Karnapke, Reinhardt and Richter, Martin and Werner, Matthias}, title = {Virtualization in robot swarms: past, present, and future}, series = {2024 IEEE 21st Consumer Communications \& Networking Conference (CCNC)}, journal = {2024 IEEE 21st Consumer Communications \& Networking Conference (CCNC)}, publisher = {IEEE}, isbn = {979-8-3503-0457-2}, doi = {10.1109/CCNC51664.2024.10454838}, pages = {1 -- 6}, abstract = {Robot swarms have come a long way since the first mobile sensor/actuator networks. Since then, we have seen the rise of operating systems for robots and swarm operating systems that ease the use of robots, and especially of large swarms of them, a lot. Still, the description of a task is often not easy and best done by experts. In this paper we envision future swarm operating systems, where task descriptions take a form which can be realized by non-experts. We describe our idea of hugely increased virtualization in the swarm and how this can be used to realize the aforementioned vision.}, language = {en} } @misc{RadushevKarkossaBergetal., author = {Radushev, Veselina and Karkossa, Isabel and Berg, Janina and Bergen, Martin von and Engelmann, Beatrice and Rolle-Kampczyk, Ulrike and Bl{\"u}her, Matthias and Wagner, Ulf and Schubert, Kristin and Rossol, Manuela}, title = {Dysregulated cytokine and oxidative response in hyper-glycolytic monocytes in obesity}, series = {Frontiers in Immunology}, volume = {15}, journal = {Frontiers in Immunology}, publisher = {Frontiers Media S.A.}, issn = {1664-3224}, doi = {10.3389/fimmu.2024.1416543}, pages = {14}, abstract = {Introduction: Obesity is associated with a plethora of health complications, including increased susceptibility to infections or decreased vaccine efficacy, partly due to dysregulated immune responses. Monocytes play a crucial role in innate immunity, yet their functional alterations in obesity remain poorly understood. Methods: Here, we employed proteomic and metabolomic analyses to investigate monocyte characteristics in individuals with overweight, obesity, impaired glucose tolerance (IGT), and type 2 diabetes (T2D), compared to lean donors. Results and discussion: Our results revealed distinct molecular signatures in monocytes from individuals with obesity, with significant alterations in pathways related to metabolism, cellular migration, and phagocytosis. Moreover, LPS-induced activation of monocytes unveiled heightened metabolic reprogramming towards glycolysis in subjects with obesity accompanied by dysregulated cytokine responses and elevated oxidative stress. Additionally, monocytes from donors with obesity exhibited increased lipid droplet accumulation. These findings shed light on the immunometabolic dysregulation underlying obesity-associated immune dysfunction, highlighting potential targets for therapeutic intervention.}, language = {en} } @misc{KieneSchottMartinCreuzburgetal., author = {Kiene, Marvin and Schott, Matthias and Martin-Creuzburg, Dominik and Laforsch, Christian}, title = {Food quantity and quality modulates inducible defenses in a common predator-prey system}, series = {Limnology and Oceanography}, volume = {69}, journal = {Limnology and Oceanography}, number = {7}, issn = {1939-5590}, doi = {10.1002/lno.12595}, pages = {1546}, language = {en} } @misc{StrobelAlvaradoChavarinKnautetal., author = {Strobel, Carsten and Alvarado Chavarin, Carlos and Knaut, Martin and Albert, Matthias and Heinzig, Andr{\´e} and Gummadi, Likhith and Wenger, Christian and Mikolajick, Thomas}, title = {p-Type Schottky contacts for graphene adjustable-Barrier phototransistors}, series = {Nanomaterials}, volume = {14}, journal = {Nanomaterials}, number = {13}, editor = {Giannazzo, Filippo and Agnello, Simonpietro and Seravalli, Luca and Bondino, Federica}, publisher = {MDPI}, issn = {2079-4991}, doi = {10.3390/nano14131140}, abstract = {The graphene adjustable-barriers phototransistor is an attractive novel device for potential high speed and high responsivity dual-band photodetection. In this device, graphene is embedded between the semiconductors silicon and germanium. Both n-type and p-type Schottky contacts between graphene and the semiconductors are required for this device. While n-type Schottky contacts are widely investigated, reports about p-type Schottky contacts between graphene and the two involved semiconductors are scarce. In this study, we demonstrate a p-type Schottky contact between graphene and p-germanium. A clear rectification with on-off ratios of close to 10 3 (±5 V) and a distinct photoresponse at telecommunication wavelengths in the infrared are achieved. Further, p-type silicon is transferred to or deposited on graphene, and we also observe rectification and photoresponse in the visible range for some of these p-type Schottky junctions. These results are an important step toward the realization of functional graphene adjustable-barrier phototransistors.}, language = {en} } @article{RaulienFriedrichStrobeletal., author = {Raulien, Nora and Friedrich, Kathleen and Strobel, Sarah and Raps, Stefanie and Hecker, Friederike and Pierer, Matthias and Schilling, Erik and Lainka, Elke and Kallinich, Tilmann and Baumann, Sven and Fritz-Wallace, Katarina and Rolle-Kampczyk, Ulrike and Bergen, Martin von and Aigner, Achim and Ewe, Alexander and Schett, Georg and Cross, Michael and Rossol, Manuela and Wagner, Ulf}, title = {Glucose-oxygen deprivation constrains HMGCR function and Rac1 prenylation and activates the NLRP3 inflammasome in human monocytes}, series = {Science Signaling}, volume = {17}, journal = {Science Signaling}, number = {845}, publisher = {American Association for the Advancement of Science (AAAS)}, issn = {1945-0877}, doi = {10.1126/scisignal.add8913}, pages = {19}, abstract = {Hypoxia and low glucose abundance often occur simultaneously at sites of inflammation. In monocytes and macrophages, glucose-oxygen deprivation stimulates the assembly of the NLRP3 inflammasome to generate the proinflammatory cytokine IL-1β. We found that concomitant glucose deprivation and hypoxia activated the NLRP3 inflammasome by constraining the function of HMG-CoA reductase (HMGCR), the rate-limiting enzyme of the mevalonate kinase pathway. HMGCR is involved in the synthesis of geranylgeranyl pyrophosphate (GGPP), which is required for the prenylation and lipid membrane integration of proteins. Under glucose-oxygen deprivation, GGPP synthesis was decreased, leading to reduced prenylation of the small GTPase Rac1, increased binding of nonprenylated Rac1 to the scaffolding protein IQGAP1, and enhanced activation of the NLRP3 inflammasome. In response to restricted oxygen and glucose supply, patient monocytes with a compromised mevalonate pathway due to mevalonate kinase deficiency or Muckle-Wells syndrome released more IL-1β than did control monocytes. Thus, reduced GGPP synthesis due to inhibition of HMGCR under glucose-oxygen deprivation results in proinflammatory innate responses, which are normally kept in check by the prenylation of Rac1. We suggest that this mechanism is also active in inflammatory autoimmune conditions.}, language = {en} } @misc{StrobelAlvaradoChavarinVoelkeletal., author = {Strobel, Carsten and Alvarado Chavarin, Carlos and V{\"o}lkel, Sandra and Jahn, Andreas and Hiess, Andre and Knaut, Martin and Albert, Matthias and Wenger, Christian and Steinke, Olaff and Stephan, Ulf and R{\"o}hlecke, S{\"o}ren and Mikolajick, Thomas}, title = {Enhanced Electrical Properties of Optimized Vertical Graphene-Base Hot Electron Transistors}, series = {ACS Applied Electronic Materials}, volume = {5}, journal = {ACS Applied Electronic Materials}, number = {3}, issn = {2637-6113}, doi = {10.1021/acsaelm.2c01725}, pages = {1670 -- 1675}, abstract = {The arrival of high-mobility two-dimensional materials like graphene leads to the renaissance of former vertical semiconductor-metal-semiconductor (SMS) hot electron transistors. Because of the monolayer thickness of graphene, improved SMS transistors with a semimetallic graphene-base electrode are now feasible for high-frequency applications. In this study we report about a device that consists of amorphous silicon, graphene, and crystalline silicon. For the first time, this device is fabricated by a four-mask lithography process which leads to significant improvements in the device performance. A strongly increased common-emitter current gain of 2\% could be achieved while the on-off ratio improved to 1.6 × 105, which is already higher than predicted theoretically. This could be mainly attributed to better interface characteristics and decreased lateral dimensions of the devices. A cutoff frequency of approximately 26 MHz could be forecasted based on the DC measurements of the device.}, language = {en} } @misc{HenkSchymuraXue, author = {Henk, Martin and Schymura, Matthias and Xue, Fei}, title = {Packing minima and lattice points in convex bodies}, series = {Moscow Journal of Combinatorics and Number Theory}, volume = {10}, journal = {Moscow Journal of Combinatorics and Number Theory}, number = {1}, publisher = {Mathematical Sciences Publishers}, issn = {2640-7361}, doi = {10.2140/moscow.2021.10.25}, pages = {25 -- 48}, abstract = {Motivated by long-standing conjectures on the discretization of classical inequalities in the geometry of numbers, we investigate a new set of parameters, which we call packing minima, associated to a convex body K and a lattice Λ. These numbers interpolate between the successive minima of K and the inverse of the successive minima of the polar body of K and can be understood as packing counterparts to the covering minima of Kannan \& Lov{\´a}sz (1988). As our main results, we prove sharp inequalities that relate the volume and the number of lattice points in K to the sequence of packing minima. Moreover, we extend classical transference bounds and discuss a natural class of examples in detail.}, language = {en} } @misc{RichterKarnapkeWerner, author = {Richter, Martin and Karnapke, Reinhardt and Werner, Matthias}, title = {Utilizing sensor and actuator virtualization to achieve a systemic view of mobile heterogeneous cyber-physical systems}, series = {Proceedings of the 14th International Conference on Simulation and Modeling Methodologies, Technologies and Applications}, journal = {Proceedings of the 14th International Conference on Simulation and Modeling Methodologies, Technologies and Applications}, publisher = {SCITEPRESS - Science and Technology Publications}, isbn = {978-989-758-708-5}, doi = {10.5220/0012715800003758}, pages = {207 -- 214}, abstract = {When programming cyber-physical systems, application developers currently utilize physical sensors and actuators individually to achieve the desired observations and impacts within the physical world. This is an error-prone and complex task given the size, heterogeneity, and mobility of prevailing cyber-physical systems. We introduce an application model that allows the application developers to take a physical perspective. By means of this model, the programmers describe desired observations and influences with respect to the physical world without directly referencing physical devices. We present an additional model for a runtime environment that transparently utilizes the available physical devices to reach the application developers' targets. We show that an implementation of our models is functional via simulation.}, language = {en} } @misc{KraljevskiDuckhornBarthetal., author = {Kraljevski, Ivan and Duckhorn, Frank and Barth, Martin and Tsch{\"o}pe, Constanze and Schubert, Frank and Wolff, Matthias}, title = {Autoencoder-based Ultrasonic NDT of Adhesive Bonds}, series = {IEEE SENSORS 2021, Conference Proceedings, Oct 31- Nov 4, Sydney, Australia}, journal = {IEEE SENSORS 2021, Conference Proceedings, Oct 31- Nov 4, Sydney, Australia}, publisher = {IEEE}, isbn = {978-1-7281-9501-8}, doi = {10.1109/SENSORS47087.2021.9639864}, pages = {4}, abstract = {We present an approach for ultrasonic non-destructive testing of adhesive bonding employing unsupervised machine learning with autoencoders.The models are trained exclusively on the features derived from pulse-echo ultrasonic signals on a specimen with good adhesive bonding and tested on another specimen with artificially added defects.The resulting pseudo-probabilities indicating anomalies are visualized and presented along to the C-scan of the same specimen. As a result, we achieved improved representation of the defects, allowing their automatic and reliable detection.}, language = {en} } @misc{BeirowNakosStecklinaetal., author = {Beirow, Bernd and Nakos, Alex and Stecklina, Caroline and Noack, Martin and Firl, Matthias and Sasakaros, Marios}, title = {Implementation of intentional mistuning by means of finite element based shape optimization}, series = {Journal of engineering for gas turbines and power}, journal = {Journal of engineering for gas turbines and power}, publisher = {ASME International}, address = {New York}, issn = {0742-4795}, doi = {10.1115/1.4069624}, pages = {1 -- 15}, abstract = {Intentional Mistuning has turned out to be an effective measure to alleviate the maximum forced response of bladed wheels in the framework of numerous studies in the past. In particular solutions based on two different blade designs, following e.g. alternating or AABB patterns, have proved to be promising in this regard and moreover robust against the impact of unavoidable random mistuning. Thus, for example, a 40 percent reduction of the first blade bending maximum forced response has been proved experimentally for a turbine impeller of a turbo charger application. Despite this success, the technical implementation of the frequency based mistuning pattern followed an academic solution based on locally removing material at the leading edge tip, which is not suited for the use in serial wheels since it may disturb the flow channel. In addition, the forced response of other blade modes may be affected in a negative manner. In order to overcome these problems, an alternative way of implementing Intentional Mistuning is suggested by applying a marginal geometric modification of the blade thickness distribution to adjust the natural frequency of the first bending mode. Finite element based shape optimization is utilized to this end. Secondary conditions are ensuring that only the target frequency of the first bending mode is adjusted whereas natural frequencies of other modes are kept almost unchanged.}, language = {en} } @misc{BeirowNakosStecklinaetal., author = {Beirow, Bernd and Nakos, Alex and Stecklina, Caroline and Noack, Martin and Firl, Matthias and Sasakaros, Marios}, title = {Implementation of intentional mistuning by means of finite element based shape optimization}, series = {Proceedings of the ASME Turbo Expo 2025, Memphis, June 16-20, 2025}, journal = {Proceedings of the ASME Turbo Expo 2025, Memphis, June 16-20, 2025}, publisher = {The American Society of Mechanical Engineers}, address = {New York, NY}, isbn = {978-0-7918-8885-8}, doi = {10.1115/GT2025-151617}, pages = {11}, abstract = {Intentional Mistuning has turned out to be an effective measure to alleviate the maximum forced response of bladed wheels in the framework of numerous studies in the past. In particular solutions based on two different blade designs, following e.g. alternating or AABB patterns, have proved to be promising in this regard and moreover robust against the impact of unavoidable random mistuning. Thus, for example, a 40 percent reduction of the first blade bending maximum forced response has been proved experimentally for a turbine impeller of a turbo charger application. Despite this success, the technical implementation of the frequency based mistuning pattern followed an academic solution based on locally removing material at the leading edge tip, which is not suited for the use in serial wheels since it may disturb the flow channel. In addition, the forced response of other blade modes may be affected in a negative manner. In order to overcome these problems, an alternative way of implementing Intentional Mistuning is suggested by applying a marginal geometric modification of the blade thickness distribution to adjust the natural frequency of the first bending mode. Finite element based shape optimization is utilized to this end. Secondary conditions are ensuring that only the target frequency of the first bending mode is adjusted whereas natural frequencies of other modes are kept almost unchanged.}, language = {en} } @techreport{KlattPfeifferBendigetal., author = {Klatt, Matthias and Pfeiffer, Klaus and Bendig, Martin and Platta, Kristian and Matzekat, David}, title = {Betrachtungen zur Mindesterzeugung von Braunkohlekraftwerken im Kontext des Netzbetriebs}, publisher = {Brandenburgische Technische Universit{\"a}t, Fachgebiet Dezentrale Energiesysteme [u.a.]}, address = {Cottbus ; Senftenberg}, language = {de} } @misc{SchmittSowoidnichGosswamietal., author = {Schmitt, Ingo and Sowoidnich, Kay and Gosswami, Tapashi and Sumpf, Bernd and Maiwald, Martin and Wolff, Matthias}, title = {PCA-based peak feature selection for classification of spectroscopic datasets}, series = {Journal of chemometrics}, volume = {39}, journal = {Journal of chemometrics}, number = {11}, publisher = {John Wiley \& Sons Ltd.}, address = {New York, NY}, issn = {0886-9383}, doi = {10.1002/cem.70074}, pages = {1 -- 14}, abstract = {Reducing feature dimensionality in spectroscopic data is crucial for efficient analysis and classification. Using all available features for classification typically results in an unacceptably high runtime and poor accuracy. Popular feature extraction methods, such as principal component analysis (PCA), linear discriminant analysis (LDA), and autoencoders, reduce feature dimensionality by extracting latent features that can be challenging to interpret. To enable better human interpretation of the classification model, we avoid extraction methods and instead propose applying feature selection methods. In this work, we develop an innovative PCA-based feature selection method for spectroscopic data, providing an essential subset of the original features. As an important advantage, no prior knowledge about the characteristic signals of the respective target substance is required. In this proof-of-concept study, the proposed method is initially characterized using simulated Raman and infrared absorption datasets. From the top five PCA eigenvectors of spectroscopic data, we identify a set of three top peaks each at specific wavenumbers (features). The compact set of selected features is then used for classification tasks applying a decision tree. Based on two well-defined spectroscopic datasets, our study demonstrates that our new method of PCA-based peak finding outperforms selected other approaches with regard to interpretability and accuracy. For both investigated datasets, accuracies greater than 97\% are achieved. Our approach shows large potential for accurate classification combined with interpretability in further scenarios involving spectroscopic datasets.}, language = {en} }