@article{LagemaatVosMaasetal.2014, author = {Lagemaat, Miriam W. and Vos, Eline K. and Maas, Marnix C. and Bitz, Andreas and Orzada, Stephan and Uden, Mark J. van and Kobus, Thiele and Heerschap, Arend and Scheenen, Tom W. J.}, title = {Phosphorus magnetic resonance spectroscopic imaging at 7 T in patients with prostate cancer}, series = {Investigative Radiology}, volume = {49}, journal = {Investigative Radiology}, number = {5}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia, Pa.}, issn = {1536-0210}, doi = {10.1097/RLI.0000000000000012}, pages = {363 -- 372}, year = {2014}, abstract = {Objectives The aim of this study was to identify characteristics of phosphorus (³¹P) spectra of the human prostate and to investigate changes of individual phospholipid metabolites in prostate cancer through in vivo ³¹P magnetic resonance spectroscopic imaging (MRSI) at 7 T. Materials and Methods In this institutional review board-approved study, 15 patients with biopsy-proven prostate cancer underwent T₂-weighted magnetic resonance imaging and 3-dimensional ³¹P MRSI at 7 T. Voxels were selected at the tumor location, in normal-appearing peripheral zone tissue, normal-appearing transition zone tissue, and in the base of the prostate close to the seminal vesicles. Phosphorus metabolite ratios were determined and compared between tissue types. Results Signals of phosphoethanolamine (PE) and phosphocholine (PC) were present and well resolved in most ³¹P spectra in the prostate. Glycerophosphocholine signals were observable in 43\% of the voxels in malignant tissue, but in only 10\% of the voxels in normal-appearing tissue away from the seminal vesicles. In many spectra, independent of tissue type, 2 peaks resonated in the chemical shift range of inorganic phosphate, possibly representing 2 separate pH compartments. The PC/PE ratio in the seminal vesicles was highly elevated compared with the prostate in 5 patients. A considerable overlap of ³¹P metabolite ratios was found between prostate cancer and normal-appearing prostate tissue, preventing direct discrimination of these tissues. The only 2 patients with high Gleason scores tumors (≥4+5) presented with high PC and glycerophosphocholine levels in their cancer lesions. Conclusions Phosphorus MRSI at 7 T shows distinct features of phospholipid metabolites in the prostate gland and its surrounding structures. In this exploratory study, no differences in ³¹P metabolite ratios were observed between prostate cancer and normal-appearing prostate tissue possibly because of the partial volume effects of small tumor foci in large MRSI voxels.}, language = {en} } @article{LambersBragard2017, author = {Lambers, Andreas and Bragard, Michael}, title = {Kinetische Skulptur - Treffen sich ein E-Techniker und ein K{\"u}nstler ...}, series = {Elektor : learn, design, share}, volume = {48}, journal = {Elektor : learn, design, share}, number = {9}, publisher = {Elektor-Verlag}, address = {Aachen}, issn = {0932-5468}, pages = {78 -- 83}, year = {2017}, abstract = {Die Verbindung der Welten dressierter Elektronen und grenzenloser Kreativit{\"a}t bietet ein großes Potential; zum Beispiel bei modernen Skulpturen, deren Form sich durch Motoren ver{\"a}ndern kann. An der FH Aachen wurde ein solches Projekt verwirklicht: Eine Matrix aus Holzkugeln kann Piktogramme anzeigen, aber auch mathematische Funktionen visualisieren. In diesem Artikel beschreiben wir die clevere Ansteuerung der Motoren.}, language = {de} } @inproceedings{LandAGligorevic2004, author = {Land, Ingmar and A., Peter and Gligorevic, Snjezana}, title = {Computation of symbol-wise mutual information in transmission systems with logAPP decoders and application to EXIT charts}, series = {5th International ITG Conference on Source and Channel Coding (SCC) : January 14 - 16, 2004, Erlangen ; conference record. (ITG-Fachbericht ; 181)}, booktitle = {5th International ITG Conference on Source and Channel Coding (SCC) : January 14 - 16, 2004, Erlangen ; conference record. (ITG-Fachbericht ; 181)}, publisher = {VDE-Verl.}, address = {Berlin [u.a.]}, organization = {International Conference Source and Channel Coding <5, 2004, Erlangen>}, isbn = {3-8007-2802-8}, pages = {195 -- 202}, year = {2004}, language = {en} } @masterthesis{Latz2021, type = {Bachelor Thesis}, author = {Latz, Annika}, title = {Konzeptentwicklung einer spielerischen Lernanwendung f{\"u}r Studierende}, school = {Fachhochschule Aachen}, pages = {XIV, 136 Seiten}, year = {2021}, abstract = {Ziel der Arbeit war es eine spielerische Lernanwendung f{\"u}r Studierende der FH-Aachen zu entwickeln, um das individuelle Lernen zu f{\"o}rdern. Dabei lag der Fokus auf der Konzeptentwicklung eines Serious Games f{\"u}r die Fachhochschule Aachen. Abgeleitet von Motivationstheorien, Game Design Frameworks und Eigenschaften von digitalen spielerischen Konzepten wurde ein Vorgehensmodell zur Konzeptentwicklung eines Serious Games erstellt. Wichtige Punkte f{\"u}r die Anwendung waren eine intensive Austauschm{\"o}glichkeiten f{\"u}r Studierende und das Integrieren dieser in die Lehrveranstaltungen der FH-Aachen. In der abschließenden Evaluation wurde positives Feedback der Studierenden eingeholt und damit das Ziel der Arbeit erreicht. Zus{\"a}tzlich wurde f{\"u}r das erarbeitete Konzept die Wirtschaftlichkeit {\"u}berpr{\"u}ft. Daf{\"u}r wurde w{\"a}hrend der Bearbeitungszeit mit einem aufgestellten Team ein Business Plan f{\"u}r das F{\"o}rderprogramm Start-Up transfer.NRW entwickelt.}, language = {de} } @article{LeingartnerMaurerFerreinetal.2016, author = {Leingartner, Max and Maurer, Johannes and Ferrein, Alexander and Steinbauer, Gerald}, title = {Evaluation of Sensors and Mapping Approaches for Disasters in Tunnels}, series = {Journal of Field Robotics}, volume = {33}, journal = {Journal of Field Robotics}, number = {8}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1556-4967}, doi = {10.1002/rob.21611}, pages = {1037 -- 1057}, year = {2016}, abstract = {Ground or aerial robots equipped with advanced sensing technologies, such as three-dimensional laser scanners and advanced mapping algorithms, are deemed useful as a supporting technology for first responders. A great deal of excellent research in the field exists, but practical applications at real disaster sites are scarce. Many projects concentrate on equipping robots with advanced capabilities, such as autonomous exploration or object manipulation. In spite of this, realistic application areas for such robots are limited to teleoperated reconnaissance or search. In this paper, we investigate how well state-of-the-art and off-the-shelf components and algorithms are suited for reconnaissance in current disaster-relief scenarios. The basic idea is to make use of some of the most common sensors and deploy some widely used algorithms in a disaster situation, and to evaluate how well the components work for these scenarios. We acquired the sensor data from two field experiments, one from a disaster-relief operation in a motorway tunnel, and one from a mapping experiment in a partly closed down motorway tunnel. Based on these data, which we make publicly available, we evaluate state-of-the-art and off-the-shelf mapping approaches. In our analysis, we integrate opinions and replies from first responders as well as from some algorithm developers on the usefulness of the data and the limitations of the deployed approaches, respectively. We discuss the lessons we learned during the two missions. These lessons are interesting for the community working in similar areas of urban search and rescue, particularly reconnaissance and search.}, language = {en} } @inproceedings{LeingartnerMaurerSteinbaueretal.2013, author = {Leingartner, Max and Maurer, Johannes and Steinbauer, Gerald and Ferrein, Alexander}, title = {Evaluation of sensors and mapping approaches for disasters in tunnels}, series = {IEEE International Symposium on Safety, Security, and Rescue Robotics : SSRR : 21-26 Oct. 2013, Linkoping, Sweden}, booktitle = {IEEE International Symposium on Safety, Security, and Rescue Robotics : SSRR : 21-26 Oct. 2013, Linkoping, Sweden}, organization = {Institute of Electrical and Electronics Engineers}, isbn = {978-1-4799-0879-0}, pages = {1 -- 7}, year = {2013}, language = {en} } @inproceedings{LeiseAltherr2018, author = {Leise, Philipp and Altherr, Lena}, title = {Optimizing the design and control of decentralized water supply systems - a case-study of a hotel building}, series = {EngOpt 2018 Proceedings of the 6th International Conference on Engineering Optimization}, booktitle = {EngOpt 2018 Proceedings of the 6th International Conference on Engineering Optimization}, publisher = {Springer}, address = {Cham}, isbn = {978-3-319-97773-7}, doi = {10.1007/978-3-319-97773-7_107}, pages = {1241 -- 1252}, year = {2018}, abstract = {To increase pressure to supply all floors of high buildings with water, booster stations, normally consisting of several parallel pumps in the basement, are used. In this work, we demonstrate the potential of a decentralized pump topology regarding energy savings in water supply systems of skyscrapers. We present an approach, based on Mixed-Integer Nonlinear Programming, that allows to choose an optimal network topology and optimal pumps from a predefined construction kit comprising different pump types. Using domain-specific scaling laws and Latin Hypercube Sampling, we generate different input sets of pump types and compare their impact on the efficiency and cost of the total system design. As a realistic application example, we consider a hotel building with 325 rooms, 12 floors and up to four pressure zones.}, language = {en} } @incollection{LeiseAltherr2021, author = {Leise, Philipp and Altherr, Lena}, title = {Experimental evaluation of resilience metrics in a fluid system}, series = {Mastering Uncertainty in Mechanical Engineering}, booktitle = {Mastering Uncertainty in Mechanical Engineering}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-78356-3}, pages = {442 -- 447}, year = {2021}, language = {en} } @inproceedings{LeiseAltherrPelz2018, author = {Leise, Philipp and Altherr, Lena and Pelz, Peter F.}, title = {Technical Operations Research (TOR) - Algorithms, not Engineers, Design Optimal Energy Efficient and Resilient Cooling Systems}, series = {FAN2018 - Proceedings of the International Conference on Fan Noise, Aerodynamics, Applications and Systems}, booktitle = {FAN2018 - Proceedings of the International Conference on Fan Noise, Aerodynamics, Applications and Systems}, pages = {1 -- 12}, year = {2018}, abstract = {The overall energy efficiency of ventilation systems can be improved by considering not only single components, but by considering as well the interplay between every part of the system. With the help of the method "TOR" ("Technical Operations Research"), which was developed at the Chair of Fluid Systems at TU Darmstadt, it is possible to improve the energy efficiency of the whole system by considering all possible design choices programmatically. We show the ability of this systematic design approach with a ventilation system for buildings as a use case example. Based on a Mixed-Integer Nonlinear Program (MINLP) we model the ventilation system. We use binary variables to model the selection of different pipe diameters. Multiple fans are model with the help of scaling laws. The whole system is represented by a graph, where the edges represent the pipes and fans and the nodes represents the source of air for cooling and the sinks, that have to be cooled. At the beginning, the human designer chooses a construction kit of different suitable fans and pipes of different diameters and different load cases. These boundary conditions define a variety of different possible system topologies. It is not possible to consider all topologies by hand. With the help of state of the art solvers, on the other side, it is possible to solve this MINLP. Next to this, we also consider the effects of malfunctions in different components. Therefore, we show a first approach to measure the resilience of the shown example use case. Further, we compare the conventional approach with designs that are more resilient. These more resilient designs are derived by extending the before mentioned model with further constraints, that consider explicitly the resilience of the overall system. We show that it is possible to design resilient systems with this method already in the early design stage and compare the energy efficiency and resilience of these different system designs.}, language = {en} } @incollection{LeiseAltherrPelz2018, author = {Leise, Philipp and Altherr, Lena and Pelz, Peter F.}, title = {Energy-Efficient design of a water supply system for skyscrapers by mixed-integer nonlinear programming}, series = {Operations Research Proceedings 2017}, booktitle = {Operations Research Proceedings 2017}, publisher = {Springer}, address = {Cham}, isbn = {978-3-319-89919-0}, doi = {10.1007/978-3-319-89920-6_63}, year = {2018}, abstract = {The energy-efficiency of technical systems can be improved by a systematic design approach. Technical Operations Research (TOR) employs methods known from Operations Research to find a global optimal layout and operation strategy of technical systems. We show the practical usage of this approach by the systematic design of a decentralized water supply system for skyscrapers. All possible network options and operation strategies are modeled by a Mixed-Integer Nonlinear Program. We present the optimal system found by our approach and highlight the energy savings compared to a conventional system design.}, language = {en} }