@phdthesis{Ehlke2020, author = {Ehlke, Moritz}, title = {3D Reconstruction of Anatomical Structures from 2D X-ray Images}, doi = {https://doi.org/10.14279/depositonce-11553}, year = {2020}, language = {en} } @article{ZiescheArltFineganetal., author = {Ziesche, Ralf F. and Arlt, Tobias and Finegan, Donal P. and Heenan, Thomas M.M. and Tengattini, Alessandro and Baum, Daniel and Kardjilov, Nikolay and Mark{\"o}tter, Henning and Manke, Ingo and Kockelmann, Winfried and Brett, Dan J.L. and Shearing, Paul R.}, title = {4D imaging of lithium-batteries using correlative neutron and X-ray tomography with a virtual unrolling technique}, series = {Nature Communications}, volume = {11}, journal = {Nature Communications}, doi = {10.1038/s41467-019-13943-3}, pages = {777}, abstract = {The temporally and spatially resolved tracking of lithium intercalation and electrode degradation processes are crucial for detecting and understanding performance losses during the operation of lithium-batteries. Here, high-throughput X-ray computed tomography has enabled the identification of mechanical degradation processes in a commercial Li/MnO2 primary battery and the indirect tracking of lithium diffusion; furthermore, complementary neutron computed tomography has identified the direct lithium diffusion process and the electrode wetting by the electrolyte. Virtual electrode unrolling techniques provide a deeper view inside the electrode layers and are used to detect minor fluctuations which are difficult to observe using conventional three dimensional rendering tools. Moreover, the 'unrolling' provides a platform for correlating multi-modal image data which is expected to find wider application in battery science and engineering to study diverse effects e.g. electrode degradation or lithium diffusion blocking during battery cycling.}, language = {en} } @article{WillschFriedrichBaumetal., author = {Willsch, Maraike and Friedrich, Frank and Baum, Daniel and Jurisch, Ivo and Ohl, Michael}, title = {A comparative description of the mesosomal musculature in Sphecidae and Ampulicidae (Hymenoptera, Apoidea) using 3D techniques}, series = {Deutsche Entomologische Zeitschrift}, volume = {67}, journal = {Deutsche Entomologische Zeitschrift}, number = {1}, doi = {10.3897/dez.67.49493}, pages = {51 -- 67}, abstract = {Conflicting hypotheses about the relationships among the major lineages of aculeate Hymenoptera clearly show the necessity of detailed comparative morphological studies. Using micro-computed tomography and 3D reconstructions, the skeletal musculature of the meso- and metathorax and the first and second abdominal segment in Apoidea are described. Females of Sceliphron destillatorium, Sphex (Fernaldina) lucae (both Sphecidae), and Ampulex compressa (Ampulicidae) were examined. The morphological terminology provided by the Hymenoptera Anatomy Ontology is used. Up to 42 muscles were found. The three species differ in certain numerical and structural aspects. Ampulicidae differs significantly from Sphecidae in the metathorax and the anterior abdomen. The metapleural apodeme and paracoxal ridge are weakly developed in Ampulicidae, which affect some muscular structures. Furthermore, the muscles that insert on the coxae and trochanters are broader and longer in Ampulicidae. A conspicuous characteristic of Sphecidae is the absence of the metaphragma. Overall, we identified four hitherto unrecognized muscles. Our work suggests additional investigations on structures discussed in this paper.}, language = {en} } @article{BorndoerferLindnerRoth, author = {Bornd{\"o}rfer, Ralf and Lindner, Niels and Roth, Sarah}, title = {A Concurrent Approach to the Periodic Event Scheduling Problem}, series = {Journal of Rail Transport Planning \& Management}, journal = {Journal of Rail Transport Planning \& Management}, number = {15}, issn = {2210-9706}, doi = {10.1016/j.jrtpm.2019.100175}, pages = {100175}, abstract = {We introduce a concurrent solver for the periodic event scheduling problem (PESP). It combines mixed integer programming techniques, the modulo network simplex method, satisfiability approaches, and a new heuristic based on maximum cuts. Running these components in parallel speeds up the overall solution process. This enables us to significantly improve the current upper and lower bounds for all benchmark instances of the library PESPlib.}, language = {en} } @misc{GrimmBorndoerferReutheretal., author = {Grimm, Boris and Bornd{\"o}rfer, Ralf and Reuther, Markus and Schlechte, Thomas}, title = {A Cut Separation Approach for the Rolling Stock Rotation Problem with Vehicle Maintenance}, series = {19th Symposium on Algorithmic Approaches for Transportation Modelling, Optimization, and Systems (ATMOS 2019)}, journal = {19th Symposium on Algorithmic Approaches for Transportation Modelling, Optimization, and Systems (ATMOS 2019)}, issn = {1438-0064}, doi = {https://doi.org/10.4230/OASIcs.ATMOS.2019.1}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-75501}, abstract = {For providing railway services the company's railway rolling stock is one if not the most important ingredient. It decides about the number of passenger or cargo trips the company can offer, about the quality a passenger experiences the train ride and it is often related to the image of the company itself. Thus, it is highly desired to have the available rolling stock in the best shape possible. Moreover, in many countries, as Germany where our industrial partner DB Fernverkehr AG (DBF) is located, laws enforce regular vehicle inspections to ensure the safety of the passengers. This leads to rolling stock optimization problems with complex rules for vehicle maintenance. This problem is well studied in the literature for example see Maroti and Kroon 2005, or Cordeau et. al. 2001 for applications including vehicle maintenance. The contribution of this paper is a new algorithmic approach to solve the Rolling Stock Rotation Problem for the ICE high speed train fleet of DBF with included vehicle maintenance. It is based on a relaxation of a mixed integer linear programming model with an iterative cut generation to enforce the feasibility of a solution of the relaxation in the solution space of the original problem. The resulting mixed integer linear programming model is based on a hypergraph approach presented in Bornd{\"o}rfer et. al. 2015. The new approach is tested on real world instances modeling different scenarios for the ICE high speed train network in Germany and compared to the approaches of Reuther 2017 that are in operation at DB Fernverkehr AG. The approach shows a significant reduction of the run time to produce solutions with comparable or even better objective function values.}, language = {en} } @misc{BorndoerferDaneckerWeiser, author = {Bornd{\"o}rfer, Ralf and Danecker, Fabian and Weiser, Martin}, title = {A Discrete-Continuous Algorithm for Free Flight Planning}, issn = {1438-0064}, doi = {10.3390/a14010004}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-81343}, abstract = {We propose a hybrid discrete-continuous algorithm for flight planning in free flight airspaces. In a first step, our DisCOptER method discrete-continuous optimization for enhanced resolution) computes a globally optimal approximate flight path on a discretization of the problem using the A* method. This route initializes a Newton method that converges rapidly to the smooth optimum in a second step. The correctness, accuracy, and complexity of the method are goverened by the choice of the crossover point that determines the coarseness of the discretization. We analyze the optimal choice of the crossover point and demonstrate the asymtotic superority of DisCOptER over a purely discrete approach.}, language = {en} } @inproceedings{YokoyamaKamadaShinanoetal.2020, author = {Yokoyama, Ryohei and Kamada, Hiroki and Shinano, Yuji and Wakui, Tetsuya}, title = {A Hierarchical Optimization Approach to Robust Design of Energy Supply Systems Based on a Mixed-Integer Linear Model}, series = {Conference}, booktitle = {Conference}, pages = {601 -- 613}, year = {2020}, abstract = {In designing energy supply systems, designers should heighten the robustness in performance criteria against the uncertainty in energy demands. In this paper, a robust optimal design method using a hierarchi- cal mixed-integer linear programming (MILP) method is proposed to maximize the robustness of energy sup- ply systems under uncertain energy demands based on a mixed-integer linear model. A robust optimal design problem is formulated as a three-level min-max-min MILP one by expressing uncertain energy demands by intervals, evaluating the robustness in a performance criterion based on the minimax regret cri- terion, and considering relationships among integer design variables, uncertain energy demands, and inte- ger and continuous operation variables. This problem is solved by evaluating upper and lower bounds for the minimum of the maximum regret of the performance criterion repeatedly outside, and evaluating lower and upper bounds for the maximum regret repeatedly inside. Since these different types of optimization problems are difficult to solve even using commercial MILP solvers, they are solved by applying a hierarchi- cal MILP method developed for ordinary optimal design problems with its modifications. In a case study, the proposed approach is applied to the robust optimal design of a cogeneration system. Through the study, its validity and effectiveness are ascertained, and some features of the obtained robust designs are clarified.}, language = {en} } @article{LeDucConrad, author = {Le Duc, Huy and Conrad, Tim}, title = {A light-weight and highly flexible software system for analyzing large bio-medical datasets}, series = {Future Generation Computer Systems}, journal = {Future Generation Computer Systems}, language = {en} } @misc{MostGiannelosYuekselErguenetal., author = {Most, Dieter and Giannelos, Spyros and Yueksel-Erguen, Inci and Beulertz, Daniel and Haus, Utz-Uwe and Charousset-Brignol, Sandrine and Frangioni, Antonio}, title = {A Novel Modular Optimization Framework for Modelling Investment and Operation of Energy Systems at European Level}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-78079}, abstract = {Project plan4res (www.plan4res.eu) involves the development of a modular framework for the modeling and analysis of energy system strategies at the European level. It will include models describing the investment and operation decisions for a wide variety of technologies related to electricity and non-electricity energy sectors across generation, consumption, transmission and distribution. The modularity of the framework allows for detailed modelling of major areas of energy systems that can help stakeholders from different backgrounds to focus on specific topics related to the energy landscape in Europe and to receive relevant outputs and insights tailored to their needs. The current paper presents a qualitative description of key concepts and methods of the novel modular optimization framework and provides insights into the corresponding energy landscape.}, language = {en} } @article{SunRehfeldtBraziletal., author = {Sun, Yahui and Rehfeldt, Daniel and Brazil, Marcus and Thomas, Doreen and Halgamuge, Saman}, title = {A Physarum-Inspired Algorithm for Minimum-Cost Relay Node Placement in Wireless Sensor Networks}, series = {IEEE/ACM Transactions on Networking}, journal = {IEEE/ACM Transactions on Networking}, doi = {10.1109/TNET.2020.2971770}, language = {en} }