@inproceedings{ElgamalHeuermann2020, author = {Elgamal, Abdelrahman and Heuermann, Holger}, title = {Design and Development of a Hot S-Parameter Measurement System for Plasma and Magnetron Applications}, series = {Proceedings of the 2020 German Microwave Conference}, booktitle = {Proceedings of the 2020 German Microwave Conference}, publisher = {IEEE}, address = {New York, NY}, isbn = {978-3-9820397-1-8}, pages = {124 -- 127}, year = {2020}, abstract = {This paper presents the design, development and calibration procedures of a novel hot S-parameter measurement system for plasma and magnetron applications with power level up to 6 kW. Based on a vector network analyzer, a power amplifier and two directional couplers, the input matching hotS 11 and transmission hotS 21 of the device under test are measured at 2.45 GHz center frequency and 300MHz bandwidth, while the device is driven by the magnetron. This measurement system opens a new horizon to develop many new industrial applications such as microwave plasma jets, dryer systems, dryers and so forth. Furthermore, the developing, controlling and monitoring a 2kW 2.45GHz plasma jet and a dryer system using the measurement system are presented and explained.}, language = {en} } @inproceedings{EltesterFerreinSchiffer2020, author = {Eltester, Niklas Sebastian and Ferrein, Alexander and Schiffer, Stefan}, title = {A smart factory setup based on the RoboCup logistics league}, series = {2020 IEEE Conference on Industrial Cyberphysical Systems (ICPS)}, booktitle = {2020 IEEE Conference on Industrial Cyberphysical Systems (ICPS)}, publisher = {IEEE}, address = {New York, NY}, doi = {10.1109/ICPS48405.2020.9274766}, pages = {297 -- 302}, year = {2020}, abstract = {In this paper we present SMART-FACTORY, a setup for a research and teaching facility in industrial robotics that is based on the RoboCup Logistics League. It is driven by the need for developing and applying solutions for digital production. Digitization receives constantly increasing attention in many areas, especially in industry. The common theme is to make things smart by using intelligent computer technology. Especially in the last decade there have been many attempts to improve existing processes in factories, for example, in production logistics, also with deploying cyber-physical systems. An initiative that explores challenges and opportunities for robots in such a setting is the RoboCup Logistics League. Since its foundation in 2012 it is an international effort for research and education in an intra-warehouse logistics scenario. During seven years of competition a lot of knowledge and experience regarding autonomous robots was gained. This knowledge and experience shall provide the basis for further research in challenges of future production. The focus of our SMART-FACTORY is to create a stimulating environment for research on logistics robotics, for teaching activities in computer science and electrical engineering programmes as well as for industrial users to study and explore the feasibility of future technologies. Building on a very successful history in the RoboCup Logistics League we aim to provide stakeholders with a dedicated facility oriented at their individual needs.}, language = {en} } @article{EmhardtJarodzkaBrandGruweletal.2020, author = {Emhardt, Selina and Jarodzka, Halszka and Brand-Gruwel, Saskia and Drumm, Christian and Gog, Tamara van}, title = {Introducing eye movement modeling examples for programming education and the role of teacher's didactic guidance}, series = {ETRA '20 Short Papers: ACM Symposium on Eye Tracking Research and Applications}, journal = {ETRA '20 Short Papers: ACM Symposium on Eye Tracking Research and Applications}, number = {Art. 52}, publisher = {ACM}, address = {New York}, doi = {10.1145/3379156.3391978}, pages = {1 -- 4}, year = {2020}, abstract = {In this article, we introduce how eye-tracking technology might become a promising tool to teach programming skills, such as debugging with 'Eye Movement Modeling Examples' (EMME). EMME are tutorial videos that visualize an expert's (e.g., a programming teacher's) eye movements during task performance to guide students' attention, e.g., as a moving dot or circle. We first introduce the general idea behind the EMME method and present studies that showed first promising results regarding the benefits of EMME to support programming education. However, we argue that the instructional design of EMME varies notably across them, as evidence-based guidelines on how to create effective EMME are often lacking. As an example, we present our ongoing research on the effects of different ways to instruct the EMME model prior to video creation. Finally, we highlight open questions for future investigations that could help improving the design of EMME for (programming) education.}, language = {en} } @article{EngemannDuKallweitetal.2020, author = {Engemann, Heiko and Du, Shengzhi and Kallweit, Stephan and C{\"o}nen, Patrick and Dawar, Harshal}, title = {OMNIVIL - an autonomous mobile manipulator for flexible production}, series = {Sensors}, volume = {20}, journal = {Sensors}, number = {24, art. no. 7249}, publisher = {MDPI}, address = {Basel}, isbn = {1424-8220}, doi = {10.3390/s20247249}, pages = {1 -- 30}, year = {2020}, language = {en} } @incollection{EngemannDuKallweitetal.2020, author = {Engemann, Heiko and Du, Shengzhi and Kallweit, Stephan and Ning, Chuanfang and Anwar, Saqib}, title = {AutoSynPose: Automatic Generation of Synthetic Datasets for 6D Object Pose Estimation}, series = {Machine Learning and Artificial Intelligence. Proceedings of MLIS 2020}, booktitle = {Machine Learning and Artificial Intelligence. Proceedings of MLIS 2020}, publisher = {IOS Press}, address = {Amsterdam}, isbn = {978-1-64368-137-5}, doi = {10.3233/FAIA200770}, pages = {89 -- 97}, year = {2020}, abstract = {We present an automated pipeline for the generation of synthetic datasets for six-dimension (6D) object pose estimation. Therefore, a completely automated generation process based on predefined settings is developed, which enables the user to create large datasets with a minimum of interaction and which is feasible for applications with a high object variance. The pipeline is based on the Unreal 4 (UE4) game engine and provides a high variation for domain randomization, such as object appearance, ambient lighting, camera-object transformation and distractor density. In addition to the object pose and bounding box, the metadata includes all randomization parameters, which enables further studies on randomization parameter tuning. The developed workflow is adaptable to other 3D objects and UE4 environments. An exemplary dataset is provided including five objects of the Yale-CMU-Berkeley (YCB) object set. The datasets consist of 6 million subsegments using 97 rendering locations in 12 different UE4 environments. Each dataset subsegment includes one RGB image, one depth image and one class segmentation image at pixel-level.}, language = {en} } @article{EveraersKarimiVarzanehFlecketal.2020, author = {Everaers, Ralf and Karimi-Varzaneh, Hossein Ali and Fleck, Franz and Hojdis, Nils and Svaneborg, Carsten}, title = {Kremer-Grest Models for Commodity Polymer Melts: Linking Theory, Experiment, and Simulation at the Kuhn Scale}, series = {Macromolecules}, volume = {53}, journal = {Macromolecules}, number = {6}, publisher = {ACS Publications}, address = {Washington, DC}, issn = {1520-5835}, doi = {10.1021/acs.macromol.9b02428}, pages = {1901 -- 1916}, year = {2020}, abstract = {The Kremer-Grest (KG) polymer model is a standard model for studying generic polymer properties in molecular dynamics simulations. It owes its popularity to its simplicity and computational efficiency, rather than its ability to represent specific polymers species and conditions. Here we show that by tuning the chain stiffness it is possible to adapt the KG model to model melts of real polymers. In particular, we provide mapping relations from KG to SI units for a wide range of commodity polymers. The connection between the experimental and the KG melts is made at the Kuhn scale, i.e., at the crossover from the chemistry-specific small scale to the universal large scale behavior. We expect Kuhn scale-mapped KG models to faithfully represent universal properties dominated by the large scale conformational statistics and dynamics of flexible polymers. In particular, we observe very good agreement between entanglement moduli of our KG models and the experimental moduli of the target polymers.}, language = {en} } @incollection{FateriGebhardt2020, author = {Fateri, Miranda and Gebhardt, Andreas}, title = {Introduction to Additive Manufacturing}, series = {3D Printing of Optical Components}, booktitle = {3D Printing of Optical Components}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-58960-8}, doi = {10.1007/978-3-030-58960-8_1}, pages = {1 -- 22}, year = {2020}, abstract = {Additive manufacturing (AM) works by creating objects layer by layer in a manner similar to a 2D printer with the "printed" layers stacked on top of each other. The layer-wise manufacturing nature of AM enables fabrication of freeform geometries which cannot be fabricated using conventional manufacturing methods as a one part. Depending on how each layer is created and bonded to the adjacent layers, different AM methods have been developed. In this chapter, the basic terms, common materials, and different methods of AM are described, and their potential applications are discussed.}, language = {en} } @article{FiedlerLaddClemensetal.2020, author = {Fiedler, Thomas M. and Ladd, Mark E. and Clemens, Markus and Bitz, Andreas}, title = {Safety of subjects during radiofrequency exposure in ultra-high-field magnetic resonance imaging}, series = {IEEE Letters on Electromagnetic Compatibility Practice and Applications}, volume = {2}, journal = {IEEE Letters on Electromagnetic Compatibility Practice and Applications}, number = {3}, publisher = {IEEE}, address = {New York, NY}, isbn = {2637-6423}, doi = {10.1109/LEMCPA.2020.3029747}, pages = {1 -- 8}, year = {2020}, abstract = {Magnetic resonance imaging (MRI) is one of the most important medical imaging techniques. Since the introduction of MRI in the mid-1980s, there has been a continuous trend toward higher static magnetic fields to obtain i.a. a higher signal-to-noise ratio. The step toward ultra-high-field (UHF) MRI at 7 Tesla and higher, however, creates several challenges regarding the homogeneity of the spin excitation RF transmit field and the RF exposure of the subject. In UHF MRI systems, the wavelength of the RF field is in the range of the diameter of the human body, which can result in inhomogeneous spin excitation and local SAR hotspots. To optimize the homogeneity in a region of interest, UHF MRI systems use parallel transmit systems with multiple transmit antennas and time-dependent modulation of the RF signal in the individual transmit channels. Furthermore, SAR increases with increasing field strength, while the SAR limits remain unchanged. Two different approaches to generate the RF transmit field in UHF systems using antenna arrays close and remote to the body are investigated in this letter. Achievable imaging performance is evaluated compared to typical clinical RF transmit systems at lower field strength. The evaluation has been performed under consideration of RF exposure based on local SAR and tissue temperature. Furthermore, results for thermal dose as an alternative RF exposure metric are presented.}, language = {en} } @article{FingerBraunBil2020, author = {Finger, Felix and Braun, Carsten and Bil, Cees}, title = {Comparative assessment of parallel-hybrid-electric propulsion systems for four different aircraft}, series = {Journal of Aircraft}, volume = {57}, journal = {Journal of Aircraft}, number = {5}, publisher = {AIAA}, address = {Reston, Va.}, issn = {1533-3868}, doi = {10.2514/1.C035897}, year = {2020}, abstract = {Until electric energy storage systems are ready to allow fully electric aircraft, the combination of combustion engine and electric motor as a hybrid-electric propulsion system seems to be a promising intermediate solution. Consequently, the design space for future aircraft is expanded considerably, as serial hybrid-electric, parallel hybrid-electric, fully electric, and conventional propulsion systems must all be considered. While the best propulsion system depends on a multitude of requirements and considerations, trends can be observed for certain types of aircraft and certain types of missions. This Paper provides insight into some factors that drive a new design toward either conventional or hybrid propulsion systems. General aviation aircraft, regional transport aircraft vertical takeoff and landing air taxis, and unmanned aerial vehicles are chosen as case studies. Typical missions for each class are considered, and the aircraft are analyzed regarding their takeoff mass and primary energy consumption. For these case studies, a high-level approach is chosen, using an initial sizing methodology. Only parallel-hybrid-electric powertrains are taken into account. Aeropropulsive interaction effects are neglected. Results indicate that hybrid-electric propulsion systems should be considered if the propulsion system is sized by short-duration power constraints. However, if the propulsion system is sized by a continuous power requirement, hybrid-electric systems offer hardly any benefit.}, language = {en} } @article{FingerBraunBil2020, author = {Finger, Felix and Braun, Carsten and Bil, Cees}, title = {Impact of Battery Performance on the Initial Sizing of Hybrid-Electric General Aviation Aircraft}, series = {Journal of Aerospace Engineering}, volume = {33}, journal = {Journal of Aerospace Engineering}, number = {3}, publisher = {ASCE}, address = {Reston, Va.}, issn = {1943-5525}, doi = {10.1061/(ASCE)AS.1943-5525.0001113}, year = {2020}, abstract = {Studies suggest that hybrid-electric aircraft have the potential to generate fewer emissions and be inherently quieter when compared to conventional aircraft. By operating combustion engines together with an electric propulsion system, synergistic benefits can be obtained. However, the performance of hybrid-electric aircraft is still constrained by a battery's energy density and discharge rate. In this paper, the influence of battery performance on the gross mass for a four-seat general aviation aircraft with a hybrid-electric propulsion system is analyzed. For this design study, a high-level approach is chosen, using an innovative initial sizing methodology to determine the minimum required aircraft mass for a specific set of requirements and constraints. Only the peak-load shaving operational strategy is analyzed. Both parallel- and serial-hybrid propulsion configurations are considered for two different missions. The specific energy of the battery pack is varied from 200 to 1,000 W⋅h/kg, while the discharge time, and thus the normalized discharge rating (C-rating), is varied between 30 min (2C discharge rate) and 2 min (30C discharge rate). With the peak-load shaving operating strategy, it is desirable for hybrid-electric aircraft to use a light, low capacity battery system to boost performance. For this case, the battery's specific power rating proved to be of much higher importance than for full electric designs, which have high capacity batteries. Discharge ratings of 20C allow a significant take-off mass reduction aircraft. The design point moves to higher wing loadings and higher levels of hybridization if batteries with advanced technology are used.}, language = {en} } @inproceedings{FingerBraunBil2020, author = {Finger, Felix and Braun, Carsten and Bil, Cees}, title = {Comparative assessment of parallel-hybrid-electric propulsion systems for four different aircraft}, series = {AIAA Scitech 2020 Forum}, booktitle = {AIAA Scitech 2020 Forum}, doi = {10.2514/6.2020-1502}, pages = {15 Seiten}, year = {2020}, abstract = {As battery technologies advance, electric propulsion concepts are on the edge of disrupting aviation markets. However, until electric energy storage systems are ready to allow fully electric aircraft, the combination of combustion engine and electric motor as a hybrid-electric propulsion system seems to be a promising intermediate solution. Consequently, the design space for future aircraft is expanded considerably, as serial-hybrid-, parallel-hybrid-, fully-electric, and conventional propulsion systems must all be considered. While the best propulsion system depends on a multitude of requirements and considerations, trends can be observed for certain types of aircraft and certain types of missions. This paper provides insight into some factors that drive a new design towards either conventional or hybrid propulsion systems. General aviation aircraft, VTOL air taxis, transport aircraft, and UAVs are chosen as case studies. Typical missions for each class are considered, and the aircraft are analyzed regarding their take-off mass and primary energy consumption. For these case studies, a high-level approach is chosen, using an initial sizing methodology. Results indicate that hybrid-electric propulsion systems should be considered if the propulsion system is sized by short-duration power constraints (e.g. take-off, climb). However, if the propulsion system is sized by a continuous power requirement (e.g. cruise), hybrid-electric systems offer hardly any benefit.}, language = {en} } @inproceedings{FingerdeVriesVosetal.2020, author = {Finger, Felix and de Vries, Reynard and Vos, Roelof and Braun, Carsten and Bil, Cees}, title = {A comparison of hybrid-electric aircraft sizing methods}, series = {AIAA Scitech 2020 Forum}, booktitle = {AIAA Scitech 2020 Forum}, doi = {10.2514/6.2020-1006}, pages = {31 Seiten}, year = {2020}, abstract = {The number of case studies focusing on hybrid-electric aircraft is steadily increasing, since these configurations are thought to lead to lower operating costs and environmental impact than traditional aircraft. However, due to the lack of reference data of actual hybrid-electric aircraft, in most cases, the design tools and results are difficult to validate. In this paper, two independently developed approaches for hybrid-electric conceptual aircraft design are compared. An existing 19-seat commuter aircraft is selected as the conventional baseline, and both design tools are used to size that aircraft. The aircraft is then re-sized under consideration of hybrid-electric propulsion technology. This is performed for parallel, serial, and fully-electric powertrain architectures. Finally, sensitivity studies are conducted to assess the validity of the basic assumptions and approaches regarding the design of hybrid-electric aircraft. Both methods are found to predict the maximum take-off mass (MTOM) of the reference aircraft with less than 4\% error. The MTOM and payload-range energy efficiency of various (hybrid-) electric configurations are predicted with a maximum difference of approximately 2\% and 5\%, respectively. The results of this study confirm a correct formulation and implementation of the two design methods, and the data obtained can be used by researchers to benchmark and validate their design tools.}, language = {en} } @article{FingerGoettenBraunetal.2020, author = {Finger, Felix and G{\"o}tten, Falk and Braun, Carsten and Bil, Cees}, title = {Mass, primary energy, and cost: the impact of optimization objectives on the initial sizing of hybrid-electric general aviation aircraft}, series = {CEAS Aeronautical Journal}, volume = {2020}, journal = {CEAS Aeronautical Journal}, number = {11}, publisher = {Springer}, address = {Heidelberg}, issn = {1869-5590}, doi = {10.1007/s13272-020-00449-8}, pages = {713 -- 730}, year = {2020}, abstract = {For short take-off and landing (STOL) aircraft, a parallel hybrid-electric propulsion system potentially offers superior performance compared to a conventional propulsion system, because the short-take-off power requirement is much higher than the cruise power requirement. This power-matching problem can be solved with a balanced hybrid propulsion system. However, there is a trade-off between wing loading, power loading, the level of hybridization, as well as range and take-off distance. An optimization method can vary design variables in such a way that a minimum of a particular objective is attained. In this paper, a comparison between the optimization results for minimum mass, minimum consumed primary energy, and minimum cost is conducted. A new initial sizing algorithm for general aviation aircraft with hybrid-electric propulsion systems is applied. This initial sizing methodology covers point performance, mission performance analysis, the weight estimation process, and cost estimation. The methodology is applied to the design of a STOL general aviation aircraft, intended for on-demand air mobility operations. The aircraft is sized to carry eight passengers over a distance of 500 km, while able to take off and land from short airstrips. Results indicate that parallel hybrid-electric propulsion systems must be considered for future STOL aircraft.}, language = {en} } @misc{FingerHojdisMenglong2020, author = {Finger, Sebastian and Hojdis, Nils and Menglong, Huang}, title = {Sekund{\"a}re galvanische Zelle}, year = {2020}, abstract = {Die vorliegende Erfindung betrifft eine sekund{\"a}re galvanische Zelle, umfassend eine Kathode, eine Anode und einen Separator, der zwischen der Kathode und der Anode angeordnet ist, wobei die Kathode ein erstes elastomeres Polymer umfasst, welches mit einem ersten F{\"u}llstoff als Kathodenmaterial gef{\"u}llt ist, wobei die Anode ein zweites elastomeres Polymer umfasst, welches mit einem zweiten F{\"u}llstoff als Anodenmaterial gef{\"u}llt ist, wobei der Separator ein drittes elastomeres Polymer umfasst, wobei das erste elastomere Polymer, das zweite elastomere Polymer und das dritte elastomere Polymer unabh{\"a}ngig voneinander aus vernetzungsf{\"a}higen Dienkautschuken ausgew{\"a}hlt sind, und wobei zumindest eines von dem ersten elastomeren Polymer, dem zweiten elastomeren Polymer und dem dritten elastomeren Polymer eine ionische Fl{\"u}ssigkeit und/oder ein elektrisch leitf{\"a}higes Polymer enth{\"a}lt. Die vorliegende Erfindung betrifft ferner eine wiederaufladbare Batterie, umfassend die erfindungsgem{\"a}ße sekund{\"a}re galvanische Zelle, ein Verfahren zur Herstellung einer sekund{\"a}ren galvanischen Zelle sowie die Verwendung der erfindungsgem{\"a}ßen sekund{\"a}ren galvanischen Zelle sowie der erfindungsgem{\"a}ßen wiederaufladbaren Batterie.}, language = {de} } @article{FinkenbergerVeil2020, author = {Finkenberger, Isabel Maria and Veil, Katja}, title = {R{\"a}umliche Transformation}, series = {RaumPlanung : Fachzeitschrift f{\"u}r r{\"a}umliche Planung und Forschung}, volume = {205}, journal = {RaumPlanung : Fachzeitschrift f{\"u}r r{\"a}umliche Planung und Forschung}, number = {1}, publisher = {IfR (Informationskreis f{\"u}r Raumplanung)}, address = {Dortmund}, issn = {0176-7534}, pages = {6 -- 11}, year = {2020}, language = {de} } @article{FrankoDuKallweitetal.2020, author = {Franko, Josef and Du, Shengzhi and Kallweit, Stephan and Duelberg, Enno Sebastian and Engemann, Heiko}, title = {Design of a Multi-Robot System for Wind Turbine Maintenance}, series = {Energies}, volume = {13}, journal = {Energies}, number = {10}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {10.3390/en13102552}, pages = {Article 2552}, year = {2020}, abstract = {The maintenance of wind turbines is of growing importance considering the transition to renewable energy. This paper presents a multi-robot-approach for automated wind turbine maintenance including a novel climbing robot. Currently, wind turbine maintenance remains a manual task, which is monotonous, dangerous, and also physically demanding due to the large scale of wind turbines. Technical climbers are required to work at significant heights, even in bad weather conditions. Furthermore, a skilled labor force with sufficient knowledge in repairing fiber composite material is rare. Autonomous mobile systems enable the digitization of the maintenance process. They can be designed for weather-independent operations. This work contributes to the development and experimental validation of a maintenance system consisting of multiple robotic platforms for a variety of tasks, such as wind turbine tower and rotor blade service. In this work, multicopters with vision and LiDAR sensors for global inspection are used to guide slower climbing robots. Light-weight magnetic climbers with surface contact were used to analyze structure parts with non-destructive inspection methods and to locally repair smaller defects. Localization was enabled by adapting odometry for conical-shaped surfaces considering additional navigation sensors. Magnets were suitable for steel towers to clamp onto the surface. A friction-based climbing ring robot (SMART— Scanning, Monitoring, Analyzing, Repair and Transportation) completed the set-up for higher payload. The maintenance period could be extended by using weather-proofed maintenance robots. The multi-robot-system was running the Robot Operating System (ROS). Additionally, first steps towards machine learning would enable maintenance staff to use pattern classification for fault diagnosis in order to operate safely from the ground in the future.}, language = {en} } @inproceedings{FrantzBinderBuschetal.2020, author = {Frantz, Cathy and Binder, Matthias and Busch, Konrad and Ebert, Miriam and Heinrich, Andreas and Kaczmarkiewicz, Nadine and Schl{\"o}gl-Knothe, B{\"a}rbel and Kunze, Tobias and Schuhbauer, Christian and Stetka, Markus and Schwager, Christian and Spiegel, Michael and Teixeira Boura, Cristiano Jos{\´e} and Bauer, Thomas and Bonk, Alexander and Eisen, Stefan and Funck, Bernhard}, title = {Basic Engineering of a High Performance Molten Salt Tower Receiver System}, series = {AIP Conference Proceedings}, booktitle = {AIP Conference Proceedings}, doi = {10.1063/5.0085895}, pages = {1 -- 10}, year = {2020}, abstract = {The production of dispatchable renewable energy will be one of the most important key factors of the future energy supply. Concentrated solar power (CSP) plants operated with molten salt as heat transfer and storage media are one opportunity to meet this challenge. Due to the high concentration factor of the solar tower technology the maximum process temperature can be further increased which ultimately decreases the levelized costs of electricity of the technology (LCOE). The development of an improved tubular molten salt receiver for the next generation of molten salt solar tower plants is the aim of this work. The receiver is designed for a receiver outlet temperature up to 600 °C. Together with a complete molten salt system, the receiver will be integrated into the Multi-Focus-Tower (MFT) in J{\"u}lich (Germany). The paper describes the basic engineering of the receiver, the molten salt tower system and a laboratory corrosion setup.}, language = {en} } @article{Gaigall2020, author = {Gaigall, Daniel}, title = {Hoeffding-Blum-Kiefer-Rosenblatt independence test statistic on partly not identically distributed data}, series = {Communications in Statistics - Theory and Methods}, volume = {51}, journal = {Communications in Statistics - Theory and Methods}, number = {12}, publisher = {Taylor \& Francis}, address = {London}, issn = {1532-415X}, doi = {10.1080/03610926.2020.1805767}, pages = {4006 -- 4028}, year = {2020}, abstract = {The established Hoeffding-Blum-Kiefer-Rosenblatt independence test statistic is investigated for partly not identically distributed data. Surprisingly, it turns out that the statistic has the well-known distribution-free limiting null distribution of the classical criterion under standard regularity conditions. An application is testing goodness-of-fit for the regression function in a non parametric random effects meta-regression model, where the consistency is obtained as well. Simulations investigate size and power of the approach for small and moderate sample sizes. A real data example based on clinical trials illustrates how the test can be used in applications.}, language = {en} } @article{Gaigall2020, author = {Gaigall, Daniel}, title = {Testing marginal homogeneity of a continuous bivariate distribution with possibly incomplete paired data}, series = {Metrika}, volume = {2020}, journal = {Metrika}, number = {83}, publisher = {Springer}, issn = {1435-926X}, doi = {10.1007/s00184-019-00742-5}, pages = {437 -- 465}, year = {2020}, abstract = {We discuss the testing problem of homogeneity of the marginal distributions of a continuous bivariate distribution based on a paired sample with possibly missing components (missing completely at random). Applying the well-known two-sample Cr{\´a}mer-von-Mises distance to the remaining data, we determine the limiting null distribution of our test statistic in this situation. It is seen that a new resampling approach is appropriate for the approximation of the unknown null distribution. We prove that the resulting test asymptotically reaches the significance level and is consistent. Properties of the test under local alternatives are pointed out as well. Simulations investigate the quality of the approximation and the power of the new approach in the finite sample case. As an illustration we apply the test to real data sets.}, language = {en} } @article{Gaigall2020, author = {Gaigall, Daniel}, title = {Rothman-Woodroofe symmetry test statistic revisited}, series = {Computational Statistics \& Data Analysis}, volume = {2020}, journal = {Computational Statistics \& Data Analysis}, number = {142}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0167-9473}, doi = {10.1016/j.csda.2019.106837}, pages = {Artikel 106837}, year = {2020}, abstract = {The Rothman-Woodroofe symmetry test statistic is revisited on the basis of independent but not necessarily identically distributed random variables. The distribution-freeness if the underlying distributions are all symmetric and continuous is obtained. The results are applied for testing symmetry in a meta-analysis random effects model. The consistency of the procedure is discussed in this situation as well. A comparison with an alternative proposal from the literature is conducted via simulations. Real data are analyzed to demonstrate how the new approach works in practice.}, language = {en} } @article{GazdaMaurischat2020, author = {Gazda, Quentin and Maurischat, Andreas}, title = {Special functions and Gauss-Thakur sums in higher rank and dimension}, publisher = {De Gruyter}, address = {Berlin}, pages = {26 Seiten}, year = {2020}, language = {en} } @inproceedings{GeibenGoettenHavermann2020, author = {Geiben, Benedikt and G{\"o}tten, Falk and Havermann, Marc}, title = {Aerodynamic analysis of a winged sub-orbital spaceplane}, publisher = {DGLR}, address = {Bonn}, doi = {10.25967/530170}, year = {2020}, abstract = {This paper primarily presents an aerodynamic CFD analysis of a winged spaceplane geometry based on the Japanese Space Walker proposal. StarCCM was used to calculate aerodynamic coefficients for a typical space flight trajectory including super-, trans- and subsonic Mach numbers and two angles of attack. Since the solution of the RANS equations in such supersonic flight regimes is still computationally expensive, inviscid Euler simulations can principally lead to a significant reduction in computational effort. The impact on accuracy of aerodynamic properties is further analysed by comparing both methods for different flight regimes up to a Mach number of 4.}, language = {en} } @article{GerhardsSanderZivkovicetal.2020, author = {Gerhards, Michael and Sander, Volker and Zivkovic, Miroslav and Belloum, Adam and Bubak, Marian}, title = {New approach to allocation planning of many-task workflows on clouds}, series = {Concurrency and Computation: Practice and Experience}, volume = {32}, journal = {Concurrency and Computation: Practice and Experience}, number = {2 Article e5404}, publisher = {Wiley}, address = {Chichester}, issn = {1532-0634}, doi = {10.1002/cpe.5404}, pages = {1 -- 16}, year = {2020}, abstract = {Experience has shown that a priori created static resource allocation plans are vulnerable to runtime deviations and hence often become uneconomic or highly exceed a predefined soft deadline. The assumption of constant task execution times during allocation planning is even more unlikely in a cloud environment where virtualized resources vary in performance. Revising the initially created resource allocation plan at runtime allows the scheduler to react on deviations between planning and execution. Such an adaptive rescheduling of a many-task application workflow is only feasible, when the planning time can be handled efficiently at runtime. In this paper, we present the static low-complexity resource allocation planning algorithm (LCP) applicable to efficiently schedule many-task scientific application workflows on cloud resources of different capabilities. The benefits of the presented algorithm are benchmarked against alternative approaches. The benchmark results show that LCP is not only able to compete against higher complexity algorithms in terms of planned costs and planned makespan but also outperforms them significantly by magnitudes of 2 to 160 in terms of required planning time. Hence, LCP is superior in terms of practical usability where low planning time is essential such as in our targeted online rescheduling scenario.}, language = {en} } @misc{Golland2020, author = {Golland, Alexander}, title = {Immaterieller Schadensersatz f{\"u}r die Weiterleitung von Daten {\"u}ber ein berufsbezogenes soziales Netzwerk}, series = {DSB Datenschutz-Berater}, volume = {44}, journal = {DSB Datenschutz-Berater}, number = {11}, publisher = {DFV Mediengruppe}, address = {Frankfurt a.M.}, issn = {0170-7256}, pages = {286 -- 288}, year = {2020}, language = {de} } @misc{Golland2020, author = {Golland, Alexander}, title = {Anspruch gegen einen Suchmaschinenbetreiber auf L{\"o}schung von Suchergebnissen}, series = {ZD Zeitschrift f{\"u}r Datenschutz}, volume = {2020}, journal = {ZD Zeitschrift f{\"u}r Datenschutz}, number = {10}, publisher = {Beck}, address = {M{\"u}nchen}, issn = {2192-5593}, pages = {531 -- 532}, year = {2020}, language = {de} } @article{Golland2020, author = {Golland, Alexander}, title = {Datenschutzrechtliche Anforderungen an internationale Datentransfers}, series = {NJW - Neue Juristische Wochenschrift}, volume = {2020}, journal = {NJW - Neue Juristische Wochenschrift}, number = {36}, publisher = {Beck}, address = {M{\"u}nchen}, issn = {0341-1915}, pages = {2593 -- 2596}, year = {2020}, language = {de} } @article{Golland2020, author = {Golland, Alexander}, title = {Die Zukunft internationaler Datentransfers: Quo vadis?}, year = {2020}, abstract = {Nach dem Scheitern des Privacy Shield hofft der Datenschutzberater Alexander Golland, dass die europ{\"a}ischen Beh{\"o}rden bald konkrete Maßnahmen f{\"u}r den Datentransfer in Drittl{\"a}nder vorschlagen. Auch kleine Unternehmen m{\"u}ssten die Herausforderung bew{\"a}ltigen - sonst w{\"a}re das Urteil nur Wasser auf die M{\"u}hlen jener, die ohnehin {\"u}ber den Datenschutz schimpfen.}, language = {de} } @article{Golland2020, author = {Golland, Alexander}, title = {Datenschutzrechtliche Fragen personalisierter Preise — Herausforderungen von Algorithmen im Schnittbereich von Ethik, {\"O}konomie und Datenschutz}, series = {CR Computer und Recht}, volume = {36}, journal = {CR Computer und Recht}, number = {3}, publisher = {Verlag Dr. Otto Schmidt}, address = {K{\"o}ln}, isbn = {2194-4172}, doi = {10.9785/cr-2020-360313}, pages = {186 -- 194}, year = {2020}, language = {de} } @misc{Golland2020, author = {Golland, Alexander}, title = {Rezension zu: Sydow - Bundesdatenschutzgesetz, Handkommentar (2020)}, series = {DSB Datenschutz-Berater}, volume = {44}, journal = {DSB Datenschutz-Berater}, number = {3}, publisher = {DFV Mediengruppe}, address = {Frankfurt a.M.}, issn = {0170-7256}, pages = {76 -- 76}, year = {2020}, language = {de} } @misc{Golland2020, author = {Golland, Alexander}, title = {Rezension zu: Spiecker gen. D{\"o}hmann/Bretthauer - Dokumentation zum Datenschutz (2019)}, series = {DSB Datenschutz-Berater}, volume = {44}, journal = {DSB Datenschutz-Berater}, number = {2}, publisher = {DFV Mediengruppe}, address = {Frankfurt a.M.}, issn = {0170-7256}, pages = {52 -- 52}, year = {2020}, language = {de} } @book{Golland2020, author = {Golland, Alexander}, title = {Kirchliches Datenschutzrecht: Datenschutz-Grundverordnung, Datenschutzvorschriften der Kirchen in Deutschland, Durchf{\"u}hrungsverordnungen und Verfahrensgesetze : Tetxsammlung / herausgegeben von Alexander Golland, mit der Stiftung Datenschutz}, edition = {2. Auflage}, publisher = {DFV Mediengruppe}, address = {Frankfurt a.M.}, isbn = {978-3-8005-1710-7}, pages = {XIII, 341 Seiten}, year = {2020}, abstract = {Textsammlung mit allen f{\"u}r den Datenschutz in Kirchen maßgeblichen Regelwerken: DSGVO, KDG, KDR-OG, DSG-EKD sowie begleitende Verordnungen (KDG-DVO, KDR-OG-DVO und ITSVO-EKD) und Verfahrensgesetze (KDSGO und KiGG.EKD). Die vorliegende Textsammlung enth{\"a}lt die f{\"u}r den Datenschutz der beiden großen Kirchen in Deutschland maßgeblichen Vorschriften: Dies sind, neben der Datenschutz-Grundverordnung, die Normen des kirchlichen Rechts, die neu erlassen bzw. ge{\"a}ndert wurden. Weiter sind die verschiedenen Durchf{\"u}hrungsverordnungen f{\"u}r die kirchlichen Datenschutzgesetze und die maßgeblichen Normen des kirchlichen Verfahrensrechts abgedruckt. Erg{\"a}nzt wird das Werk durch Verweise auf maßgebliche Ver{\"o}ffentlichungen der weltlichen und kirchlichen Datenschutzaufsichtsbeh{\"o}rden und weitere Materialien.}, language = {de} } @misc{Golland2020, author = {Golland, Alexander}, title = {Rezension zu: Gabel/Heinrich/Kiefner - Rechtshandbuch Cyber-Security (2019)}, series = {K\&R Kommunikation \& Recht}, journal = {K\&R Kommunikation \& Recht}, number = {6}, issn = {1434-6354}, pages = {VII}, year = {2020}, language = {de} } @incollection{Golland2020, author = {Golland, Alexander}, title = {Struggling with users' consent: Economic approach to solve the issue of coupling}, series = {Turning Point in Data Protection Law}, booktitle = {Turning Point in Data Protection Law}, publisher = {Nomos}, address = {Baden-Baden}, isbn = {978-3-8487-6909-4}, doi = {10.5771/9783748921561-121}, pages = {121 -- 126}, year = {2020}, language = {en} } @article{Golland2020, author = {Golland, Alexander}, title = {Die „private" Datenverarbeitung im Internet. Verantwortlichkeiten und Rechtm{\"a}ßigkeit bei Nutzung von Plattformdiensten durch nat{\"u}rliche Personen}, series = {ZD Zeitschrift f{\"u}r Datenschutz}, volume = {10}, journal = {ZD Zeitschrift f{\"u}r Datenschutz}, number = {8}, editor = {Hoeren, Thomas and Schneider, Jochen and Selmayr, Martin and Spies, Axel and Wybitul, Tim}, publisher = {Beck}, address = {M{\"u}nchen}, isbn = {2192-5593}, pages = {397 -- 403}, year = {2020}, language = {de} } @article{Golland2020, author = {Golland, Alexander}, title = {Weckruf f{\"u}r deutsche Großunternehmen? - Der neue Entwurf des IT-Sicherheitsgesetz 2.0}, series = {K\&R Kommunikation \& Recht}, volume = {23}, journal = {K\&R Kommunikation \& Recht}, number = {7-8}, publisher = {DFV Mediengruppe}, address = {Frankfurt a.M.}, isbn = {1434-6354}, pages = {I}, year = {2020}, language = {de} } @article{Golland2020, author = {Golland, Alexander}, title = {EDPB: Europ{\"a}ische Aufsichtsbeh{\"o}rden mit neuen Guidelines zur datenschutzkonformen Einwilligung}, series = {DSB Datenschutz-Berater}, volume = {44}, journal = {DSB Datenschutz-Berater}, number = {6}, publisher = {DFV Mediengruppe}, address = {Frankfurt a.M.}, isbn = {0170-7256}, pages = {151 -- 153}, year = {2020}, language = {de} } @article{Golland2020, author = {Golland, Alexander}, title = {Verantwortlichkeit, Data Breach, das Ende von Fax \& E-Mail: Aufsichtsbeh{\"o}rden mit streitbaren Thesen}, series = {DSB Datenschutz-Berater}, volume = {44}, journal = {DSB Datenschutz-Berater}, number = {4}, publisher = {DFV Mediengruppe}, address = {Frankfurt a.M.}, isbn = {0170-7256}, pages = {98 -- 100}, year = {2020}, language = {de} } @misc{Golland2020, author = {Golland, Alexander}, title = {Rezension zu: Auernhammer - DSGVO/BDSG, Kommentar (7. Auflage, 2020)}, series = {DSB Datenschutz-Berater}, volume = {44}, journal = {DSB Datenschutz-Berater}, number = {10}, publisher = {DFV Mediengruppe}, address = {Frankfurt a.M.}, issn = {0170-7256}, pages = {260}, year = {2020}, language = {de} } @misc{Golland2020, author = {Golland, Alexander}, title = {Rezension zu: Hansen-Oest - Datenschutzbeauftragte (2020)}, series = {DSB Datenschutz-Berater}, volume = {44}, journal = {DSB Datenschutz-Berater}, number = {9}, publisher = {DFV Mediengruppe}, address = {Frankfurt a.M.}, issn = {0170-7256}, pages = {228}, year = {2020}, language = {de} } @misc{Golland2020, author = {Golland, Alexander}, title = {Rezension zu: Kipker - Rechtshandbuch Cybersecurity (2020)}, series = {DSB Datenschutz-Berater}, volume = {44}, journal = {DSB Datenschutz-Berater}, number = {7-8}, publisher = {DFV Mediengruppe}, address = {Frankfurt a.M.}, issn = {0170-7256}, pages = {192}, year = {2020}, language = {de} } @incollection{GollandOhrtmann2020, author = {Golland, Alexander and Ohrtmann, Jan-Peter}, title = {Video surveillance: The supervisory authorities' view andrecent case law}, series = {Turning Point in Data Protection Law}, booktitle = {Turning Point in Data Protection Law}, publisher = {Nomos}, address = {Baden-Baden}, isbn = {978-3-8487-6909-4}, doi = {10.5771/9783748921561-175}, pages = {175 -- 178}, year = {2020}, language = {en} } @article{GossmannThomasHorvathetal.2020, author = {Gossmann, Matthias and Thomas, Ulrich and Horv{\´a}th, Andr{\´a}s and Dragicevic, Elena and Stoelzle-Feix, Sonja and Jung, Alexander and Raman, Aravind Hariharan and Staat, Manfred and Linder, Peter}, title = {A higher-throughput approach to investigate cardiac contractility in vitro under physiological mechanical conditions}, series = {Journal of Pharmacological and Toxicological Methods}, volume = {105}, journal = {Journal of Pharmacological and Toxicological Methods}, number = {Article 106843}, publisher = {Elsevier}, address = {New York, NY}, doi = {10.1016/j.vascn.2020.106843}, year = {2020}, language = {en} } @article{GoettenFinger2020, author = {G{\"o}tten, Falk and Finger, Felix}, title = {PhoenAIX - Die modulare Transportdrohne}, series = {Ingenieurspiegel}, volume = {2020}, journal = {Ingenieurspiegel}, number = {1}, publisher = {Public Verlag}, address = {Bingen}, isbn = {1868-5919}, pages = {38 -- 40}, year = {2020}, abstract = {Die autonome, unbemannte Luftfahrt ist einer der Schl{\"u}sselsektoren f{\"u}r die Zukunft der Luftfahrt. In diesem rasant wachsenden Bereich nehmen senkrecht startende und senkrecht landende Flugzeuge (Vertical Take-Off and Landing - VTOL) einen besonderen Platz ein. Ein VTOL-Flugzeug (manchmal auch „Transitionsflugger{\"a}t" genannt) verbindet die Eigenschaft des Helikopters, {\"u}berall starten und landen zu k{\"o}nnen, mit den Geschwindigkeits-, Reichweiten und Flugdauervorteilen des Starrfl{\"u}glers. Grunds{\"a}tzlich wird die Senkrechtstart- und -landef{\"a}higkeit sowohl von zivilen als auch von milit{\"a}rischen Betreibern unbemannter Flugger{\"a}te (UAVs) gew{\"u}nscht. Trotzdem bietet der Markt nur eine geringe Anzahl von VTOL-UAVs, da qualitativ hochwertige Entw{\"u}rfe eine ausgesprochene Herausforderung in der Entwicklung darstellen. An der FH Aachen wird deshalb seit {\"u}ber 5 Jahren an der Auslegung und Analyse von solchen unbemannten VTOL Flugzeugen geforscht. Das neuste Projekt ist der Eigenentwurf einer großen, senkrechtstartenden Transportdrohne. Das „PhoenAIX" getaufte Flugger{\"a}t wird von Falk G{\"o}tten und Felix Finger im Rahmen einer EFRE-F{\"o}rderung entwickelt.}, language = {de} } @inproceedings{GoettenFingerHavermannetal.2020, author = {G{\"o}tten, Falk and Finger, Felix and Havermann, Marc and Braun, Carsten and Marino, Matthew and Bil, Cees}, title = {Full Configuration Drag Estimation of Small-to-Medium Range UAVs and its Impact on Initial Sizing Optimization}, series = {CEAS Aeronautical Journal}, volume = {12}, booktitle = {CEAS Aeronautical Journal}, publisher = {Springer}, address = {Wien}, issn = {1869-5590}, doi = {10.1007/s13272-021-00522-w}, pages = {589 -- 603}, year = {2020}, abstract = {The paper presents the derivation of a new equivalent skin friction coefficient for estimating the parasitic drag of short-to-medium range fixed-wing unmanned aircraft. The new coefficient is derived from an aerodynamic analysis of ten different unmanned aircraft used on surveillance, reconnaissance, and search and rescue missions. The aircraft are simulated using a validated unsteady Reynolds-averaged Navier Stokes approach. The UAV's parasitic drag is significantly influenced by the presence of miscellaneous components like fixed landing gears or electro-optical sensor turrets. These components are responsible for almost half of an unmanned aircraft's total parasitic drag. The new equivalent skin friction coefficient accounts for these effects and is significantly higher compared to other aircraft categories. It is used to initially size an unmanned aircraft for a typical reconnaissance mission. The improved parasitic drag estimation yields a much heavier unmanned aircraft when compared to the sizing results using available drag data of manned aircraft.}, language = {en} } @article{GoettenHavermannBraunetal.2020, author = {G{\"o}tten, Falk and Havermann, Marc and Braun, Carsten and Marino, Matthew and Bil, Cees}, title = {Wind-tunnel and CFD investigations of UAV landing gears and turrets - Improvements in empirical drag estimation}, series = {Aerospace Science and Technology}, volume = {107}, journal = {Aerospace Science and Technology}, number = {Art. 106306}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1270-9638}, doi = {10.1016/j.ast.2020.106306}, year = {2020}, abstract = {This paper analyzes the drag characteristics of several landing gear and turret configurations that are representative of unmanned aircraft tricycle landing gears and sensor turrets. A variety of these components were constructed via 3D-printing and analyzed in a wind-tunnel measurement campaign. Both turrets and landing gears were attached to a modular fuselage that supported both isolated components and multiple components at a time. Selected cases were numerically investigated with a Reynolds-averaged Navier-Stokes approach that showed good accuracy when compared to wind-tunnel data. The drag of main gear struts could be significantly reduced via streamlining their cross-sectional shape and keeping load carrying capabilities similar. The attachment of wheels introduced interference effects that increased strut drag moderately but significantly increased wheel drag compared to isolated cases. Very similar behavior was identified for front landing gears. The drag of an electro-optical and infrared sensor turret was found to be much higher than compared to available data of a clean hemisphere-cylinder combination. This turret drag was merely influenced by geometrical features like sensor surfaces and the rotational mechanism. The new data of this study is used to develop simple drag estimation recommendations for main and front landing gear struts and wheels as well as sensor turrets. These recommendations take geometrical considerations and interference effects into account.}, language = {en} } @article{GoettenHavermannBraunetal.2020, author = {G{\"o}tten, Falk and Havermann, Marc and Braun, Carsten and Marino, Matthew and Bil, Cees}, title = {Improved Form Factor for Drag Estimation of Fuselages with Various Cross Sections}, series = {Journal of Aircraft}, journal = {Journal of Aircraft}, publisher = {AIAA}, address = {Reston, Va.}, issn = {1533-3868}, doi = {10.2514/1.C036032}, pages = {1 -- 13}, year = {2020}, abstract = {The paper presents an aerodynamic investigation of 70 different streamlined bodies with fineness ratios ranging from 2 to 10. The bodies are chosen to idealize both unmanned and small manned aircraft fuselages and feature cross-sectional shapes that vary from circular to quadratic. The study focuses on friction and pressure drag in dependency of the individual body's fineness ratio and cross section. The drag forces are normalized with the respective body's wetted area to comply with an empirical drag estimation procedure. Although the friction drag coefficient then stays rather constant for all bodies, their pressure drag coefficients decrease with an increase in fineness ratio. Referring the pressure drag coefficient to the bodies' cross-sectional areas shows a distinct pressure drag minimum at a fineness ratio of about three. The pressure drag of bodies with a quadratic cross section is generally higher than for bodies of revolution. The results are used to derive an improved form factor that can be employed in a classic empirical drag estimation method. The improved formulation takes both the fineness ratio and cross-sectional shape into account. It shows superior accuracy in estimating streamlined body drag when compared with experimental data and other form factor formulations of the literature.}, language = {en} } @article{GoettenHavermannBraunetal.2020, author = {G{\"o}tten, Falk and Havermann, Marc and Braun, Carsten and Marino, Matthew and Bil, Cees}, title = {Airfoil drag at low-to-medium reynolds numbers: A novel estimation method}, series = {AIAA Journal}, volume = {58}, journal = {AIAA Journal}, number = {7}, publisher = {AIAA}, address = {Reston, Va.}, issn = {1533-385X}, doi = {10.2514/1.J058983}, pages = {2791 -- 2805}, year = {2020}, abstract = {This paper presents a novel method for airfoil drag estimation at Reynolds numbers between 4×10⁵ and 4×10⁶. The novel method is based on a systematic study of 40 airfoils applying over 600 numerical simulations and considering natural transition. The influence of the airfoil thickness-to-chord ratio, camber, and freestream Reynolds number on both friction and pressure drag is analyzed in detail. Natural transition significantly affects drag characteristics and leads to distinct drag minima for different Reynolds numbers and thickness-to-chord ratios. The results of the systematic study are used to develop empirical correlations that can accurately predict an airfoil drag at low-lift conditions. The new approach estimates a transition location based on airfoil thickness-to-chord ratio, camber, and Reynolds number. It uses the transition location in a mixed laminar-turbulent skin-friction calculation, and corrects the skin-friction coefficient for separation effects. Pressure drag is estimated separately based on correlations of thickness-to-chord ratio, camber, and Reynolds number. The novel method shows excellent accuracy when compared with wind-tunnel measurements of multiple airfoils. It is easily integrable into existing aircraft design environments and is highly beneficial in the conceptual design stage.}, language = {en} } @article{HailerWeberNevelingetal.2020, author = {Hailer, Benjamin and Weber, Tobias and Neveling, Sebastian and Dera, Samuel and Arent, Jan-Christoph and Middendorf, Peter}, title = {Development of a test device to determine the frictional behavior between honeycomb and prepreg layers under realistic manufacturing conditions}, series = {Journal of Sandwich Structures \& Materials}, journal = {Journal of Sandwich Structures \& Materials}, number = {Volume 23, Issue 7}, publisher = {Sage}, address = {London}, issn = {1530-7972}, doi = {10.1177/1099636220923986}, pages = {3017 -- 3043}, year = {2020}, abstract = {In the friction tests between honeycomb with film adhesive and prepreg, the relative displacement occurs between the film adhesive and the prepreg. The film adhesive does not shift relative to the honeycomb. This is consistent with the core crush behavior where the honeycomb moves together with the film adhesive, as can be seen in Figure 2(a). The pull-through forces of the friction measurements between honeycomb and prepreg at 1 mm deformation are plotted in Figure 17(a). While the friction at 100°C is similar to the friction at 120°C, it decreases significantly at 130°C and exhibits a minimum at 140°C. At 150°C, the friction rises again slightly and then sharply at 160°C. Since the viscosity of the M18/1 prepreg resin drops significantly before it cures [23], the minimum friction at 140°C could result from a minimum viscosity of the mixture of prepreg resin and film adhesive before the bond subsequently cures. Figure 17(b) shows the mean value curve of the friction measurements at 140°C. The error bars, which represent the standard deviation, reveal the good repeatability of the tests. The force curve is approximately horizontal between 1 mm and 2 mm. The friction then slightly rises. As with interlaminar friction measurements, this could be due to the fact that resin is removed by friction and the proportion of boundary lubrication increases. Figure 18 shows the surfaces after the friction measurement. The honeycomb cell walls are clearly visible in the film adhesive. There are areas where the film adhesive is completely removed and the carrier material of the film adhesive becomes visible. In addition, the viscosity of the resin changes as the curing progresses during the friction test. This can also affect the force-displacement curve.}, language = {en} } @article{HamouKotliarTanetal.2020, author = {Hamou, Hussam Aldin and Kotliar, Konstantin and Tan, Sonny Kian and Weiß, Christel and Blume, Christian and Clusmann, Hans and Schubert, Gerrit Alexander and Albanna, Walid}, title = {Surgical nuances and placement of subgaleal drains for supratentorial procedures—a prospective analysis of efficacy and outcome in 150 craniotomies}, series = {Acta Neurochirurgica}, volume = {2020}, journal = {Acta Neurochirurgica}, number = {162}, publisher = {Springer Nature}, address = {Cham}, issn = {0942-0940}, doi = {10.1007/s00701-019-04196-6}, pages = {729 -- 736}, year = {2020}, abstract = {Background For supratentorial craniotomy, surgical access, and closure technique, including placement of subgaleal drains, may vary considerably. The influence of surgical nuances on postoperative complications such as cerebrospinal fluid leakage or impaired wound healing overall remains largely unclear. With this study, we are reporting our experiences and the impact of our clinical routines on outcome in a prospectively collected data set. Method We prospectively observed 150 consecutive patients undergoing supratentorial craniotomy and recorded technical variables (type/length of incision, size of craniotomy, technique of dural and skin closure, type of dressing, and placement of subgaleal drains). Outcome variables (subgaleal hematoma/CSF collection, periorbital edema, impairment of wound healing, infection, and need for operative revision) were recorded at time of discharge and at late follow-up. Results Early subgaleal fluid collection was observed in 36.7\% (2.8\% at the late follow-up), and impaired wound healing was recorded in 3.3\% of all cases, with an overall need for operative revision of 6.7\%. Neither usage of dural sealants, lack of watertight dural closure, and presence of subgaleal drains, nor type of skin closure or dressing influenced outcome. Curved incisions, larger craniotomy, and tumor size, however, were associated with an increase in early CSF or hematoma collection (p < 0.0001, p = 0.001, p < 0.01 resp.), and larger craniotomy size was associated with longer persistence of subgaleal fluid collections (p < 0.05). Conclusions Based on our setting, individual surgical nuances such as the type of dural closure and the use of subgaleal drains resulted in a comparable complication rate and outcome. Subgaleal fluid collections were frequently observed after supratentorial procedures, irrespective of the closing technique employed, and resolve spontaneously in the majority of cases without significant sequelae. Our results are limited due to the observational nature in our single-center study and need to be validated by supportive prospective randomized design.}, language = {en} } @inproceedings{HauggKreyerKemperetal.2020, author = {Haugg, Albert Thomas and Kreyer, J{\"o}rg and Kemper, Hans and Hatesuer, Katerina and Esch, Thomas}, title = {Heat exchanger for ORC. adaptability and optimisation potentials}, series = {IIR International Rankine 2020 Conference}, booktitle = {IIR International Rankine 2020 Conference}, doi = {10.18462/iir.rankine.2020.1224}, pages = {10 Seiten}, year = {2020}, abstract = {The recovery of waste heat requires heat exchangers to extract it from a liquid or gaseous medium into another working medium, a refrigerant. In Organic Rankine Cycles (ORC) on Combustion Engines there are two major heat sources, the exhaust gas and the water/glycol fluid from the engine's cooling circuit. A heat exchanger design must be adapted to the different requirements and conditions resulting from the heat sources, fluids, system configurations, geometric restrictions, and etcetera. The Stacked Shell Cooler (SSC) is a new and very specific design of a plate heat exchanger, created by AKG, which allows with a maximum degree of freedom the optimization of heat exchange rate and the reduction of the related pressure drop. This optimization in heat exchanger design for ORC systems is even more important, because it reduces the energy consumption of the system and therefore maximizes the increase in overall efficiency of the engine.}, language = {en} }