TY - CHAP A1 - Krause, Thomas T1 - Baumaschinen T2 - Übungsaufgaben und Berechnungen für den Baubetrieb Y1 - 2019 SN - 978-3-658-23127-9 U6 - http://dx.doi.org/10.1007/978-3-658-23127-9_7 SP - 155 EP - 163 PB - Springer Vieweg CY - Wiesbaden ER - TY - CHAP A1 - Ernhardt, Selina A1 - Drumm, Christian A1 - van Gog, Tamara A1 - Brand-Gruwel, Saskia A1 - Jarodzka, Halszka T1 - Through the eyes of a programmer : a research project on how to foster programming education with eye-tracking technology T2 - Tagungsband zur 32. AKWI-Jahrestagung vom 15.09.2019 bis 18.09.2019 an der Fachhochschule für Angewandte Wissenschaften Aachen Y1 - 2019 SN - 978-3-944330-62-4 SP - 42 EP - 47 PB - Mana-Buch CY - Heide ER - TY - CHAP A1 - Finkenberger, Isabel Maria A1 - Baumeister, Eva-Maria A1 - Koch, Christian T1 - Komplement und Verstärker : Wandel durch neue Allianzen T1 - Amplifier and complement : creating change through new alliances T2 - Komplement und Verstärker : zum Verhältnis von Stadtplanung, künstlerischen Praktiken und Kulturinstitutionen Y1 - 2019 SN - 978-3-86859-578-9 SP - 10 EP - 39 PB - JOVIS Verlag CY - Berlin ER - TY - CHAP A1 - Finkenberger, Isabel Maria A1 - Baumeister, Eva-Maria A1 - Koch, Christian T1 - Komplement und Verstärker : der Diskurs geht weiter T1 - Amplifier and complement : the discourse continues T2 - Komplement und Verstärker : zum Verhältnis von Stadtplanung, künstlerischen Praktiken und Kulturinstitutionen Y1 - 2019 SN - 978-3-86859-578-9 SP - 40 EP - 49 PB - JOVIS Verlag CY - Berlin ER - TY - CHAP A1 - Finkenberger, Isabel Maria A1 - Herbert, Saskia A1 - Malorny, Thomas A1 - Koch, Christian T1 - Perforierte Wirklichkeit und mögliche Zukünfte : ein Gespräch T1 - Perforated reality and possible futures : a conversation T2 - Komplement und Verstärker : zum Verhältnis von Stadtplanung, künstlerischen Praktiken und Kulturinstitutionen Y1 - 2019 SN - 978-3-86859-578-9 SP - 108 EP - 129 PB - JOVIS Verlag CY - Berlin ER - TY - CHAP A1 - Finkenberger, Isabel Maria A1 - Baumeister, Eva-Maria A1 - Koch, Christian T1 - Themen T1 - Topics T2 - Komplement und Verstärker: zum Verhältnis von Stadtplanung, künstlerischen Praktiken und Kulturinstitutionen Y1 - 2019 SN - 978-3-86859-578-9 SP - 50 EP - 57 PB - JOVIS Verlag CY - Berlin ER - TY - CHAP A1 - Finkenberger, Isabel Maria A1 - Baumeister, Eva-Maria ED - Berger, Hilke Marit ED - Ziemer, Gesa T1 - Working in between : Die Stadt von der anderen Seite sehen : Where Urban Planning Meets Artistic Practice T2 - New Stakeholders of Urban Change : A Question of Culture and Attitude?. - (Perspectives in Metropolitan Research ; IV) Y1 - 2017 SN - 978-3-86859-487-4 SP - 119 EP - 129 PB - JOVIS Verlag CY - Berlin ER - TY - CHAP A1 - Laack, Walter van T1 - Twee Kanten van één Medaille T2 - Het Geheim van Elysion : 45 Jaar Studies naar Nabij-de-Dood-Ervaringen over Bewustzijn in Liefde zonder Waarheen Y1 - 2020 SN - 978-94-93175-44-0 SP - 97 EP - 105 PB - Van Warven CY - Kampen ER - TY - CHAP A1 - Hoffschmidt, Bernhard A1 - Alexopoulos, Spiros A1 - Rau, Christoph A1 - Sattler, Johannes, Christoph A1 - Anthrakidis, Anette A1 - Teixeira Boura, Cristiano José A1 - O’Connor, B. A1 - Caminos, R.A. Chico A1 - Rendón, C. A1 - Hilger, P. T1 - Concentrating Solar Power T2 - Earth systems and environmental sciences N2 - The focus of this chapter is the production of power and the use of the heat produced from concentrated solar thermal power (CSP) systems. The chapter starts with the general theoretical principles of concentrating systems including the description of the concentration ratio, the energy and mass balance. The power conversion systems is the main part where solar-only operation and the increase in operational hours. Solar-only operation include the use of steam turbines, gas turbines, organic Rankine cycles and solar dishes. The operational hours can be increased with hybridization and with storage. Another important topic is the cogeneration where solar cooling, desalination and of heat usage is described. Many examples of commercial CSP power plants as well as research facilities from the past as well as current installed and in operation are described in detail. The chapter closes with economic and environmental aspects and with the future potential of the development of CSP around the world. KW - Central receiver power plant KW - Concentrated systems KW - Concentrating solar power KW - Fresnel power plant KW - Gas turbine Y1 - 2021 SN - 978-0-12-409548-9 U6 - http://dx.doi.org/10.1016/B978-0-12-819727-1.00089-3 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Altherr, Lena A1 - Ederer, Thorsten A1 - Lorenz, Ulf A1 - Pelz, Peter F. A1 - Pöttgen, Philipp ED - Lübbecke, Marco E. ED - Koster, Arie ED - Letmathe, Peter ED - Madlener, Reihard ED - Preis, Britta ED - Walther, Grit T1 - Designing a feedback control system via mixed-integer programming T2 - Operations Research Proceedings 2014: Selected Papers of the Annual International Conference of the German Operations Research N2 - Pure analytical or experimental methods can only find a control strategy for technical systems with a fixed setup. In former contributions we presented an approach that simultaneously finds the optimal topology and the optimal open-loop control of a system via Mixed Integer Linear Programming (MILP). In order to extend this approach by a closed-loop control we present a Mixed Integer Program for a time discretized tank level control. This model is the basis for an extension by combinatorial decisions and thus for the variation of the network topology. Furthermore, one is able to appraise feasible solutions using the global optimality gap. KW - Optimal Topology KW - Controller Parameter KW - Level Control System KW - Technical Operation Research KW - Optimal Closed Loop Y1 - 2016 SN - 978-3-319-28695-2 U6 - http://dx.doi.org/10.1007/978-3-319-28697-6_18 SP - 121 EP - 127 PB - Springer CY - Cham ER - TY - CHAP A1 - Kotliar, Konstantin ED - Pallikaris, I. ED - Tsilimbaris, M. K. ED - Dastiridou, A. I. T1 - Ocular rigidity: clinical approach T2 - Ocular Rigidity, Biomechanics and Hydrodynamics of the Eye N2 - The term ocular rigidity is widely used in clinical ophthalmology. Generally it is assumed as a resistance of the whole eyeball to mechanical deformation and relates to biomechanical properties of the eye and its tissues. Basic principles and formulas for clinical tonometry, tonography and pulsatile ocular blood flow measurements are based on the concept of ocular rigidity. There is evidence for altered ocular rigidity in aging, in several eye diseases and after eye surgery. Unfortunately, there is no consensual view on ocular rigidity: it used to make a quite different sense for different people but still the same name. Foremost there is no clear consent between biomechanical engineers and ophthalmologists on the concept. Moreover ocular rigidity is occasionally characterized using various parameters with their different physical dimensions. In contrast to engineering approach, clinical approach to ocular rigidity claims to characterize the total mechanical response of the eyeball to its deformation without any detailed considerations on eye morphology or material properties of its tissues. Further to the previous chapter this section aims to describe clinical approach to ocular rigidity from the perspective of an engineer in an attempt to straighten out this concept, to show its advantages, disadvantages and various applications. KW - Coefficient of ocular rigidity KW - Eyeball KW - Corneo-scleral shell KW - Pressure-volume relationship KW - Differential tonometry Y1 - 2021 SN - 978-3-030-64422-2 U6 - http://dx.doi.org/10.1007/978-3-030-64422-2_2 SP - 15 EP - 43 PB - Springer CY - Cham ER - TY - CHAP A1 - Pfetsch, Marc E. A1 - Abele, Eberhard A1 - Altherr, Lena A1 - Bölling, Christian A1 - Brötz, Nicolas A1 - Dietrich, Ingo A1 - Gally, Tristan A1 - Geßner, Felix A1 - Groche, Peter A1 - Hoppe, Florian A1 - Kirchner, Eckhard A1 - Kloberdanz, Hermann A1 - Knoll, Maximilian A1 - Kolvenbach, Philip A1 - Kuttich-Meinlschmidt, Anja A1 - Leise, Philipp A1 - Lorenz, Ulf A1 - Matei, Alexander A1 - Molitor, Dirk A. A1 - Niessen, Pia A1 - Pelz, Peter F. A1 - Rexer, Manuel A1 - Schmitt, Andreas A1 - Schmitt, Johann M. A1 - Schulte, Fiona A1 - Ulbrich, Stefan A1 - Weigold, Matthias T1 - Strategies for mastering uncertainty T2 - Mastering uncertainty in mechanical engineering N2 - This chapter describes three general strategies to master uncertainty in technical systems: robustness, flexibility and resilience. It builds on the previous chapters about methods to analyse and identify uncertainty and may rely on the availability of technologies for particular systems, such as active components. Robustness aims for the design of technical systems that are insensitive to anticipated uncertainties. Flexibility increases the ability of a system to work under different situations. Resilience extends this characteristic by requiring a given minimal functional performance, even after disturbances or failure of system components, and it may incorporate recovery. The three strategies are described and discussed in turn. Moreover, they are demonstrated on specific technical systems. Y1 - 2021 SN - 978-3-030-78353-2 U6 - http://dx.doi.org/10.1007/978-3-030-78354-9_6 N1 - Part of the Springer Tracts in Mechanical Engineering book series (STME) SP - 365 EP - 456 PB - Springer CY - Cham ER - TY - CHAP A1 - Leise, Philipp A1 - Altherr, Lena A1 - Simon, Nicolai A1 - Pelz, Peter F. T1 - Finding global-optimal gearbox designs for battery electric vehicles T2 - Optimization of complex systems - theory, models, algorithms and applications : WCGO 2019 N2 - In order to maximize the possible travel distance of battery electric vehicles with one battery charge, it is mandatory to adjust all components of the powertrain carefully to each other. While current vehicle designs mostly simplify the powertrain rigorously and use an electric motor in combination with a gearbox with only one fixed transmission ratio, the use of multi-gear systems has great potential. First, a multi-speed system is able to improve the overall energy efficiency. Secondly, it is able to reduce the maximum momentum and therefore to reduce the maximum current provided by the traction battery, which results in a longer battery lifetime. In this paper, we present a systematic way to generate multi-gear gearbox designs that—combined with a certain electric motor—lead to the most efficient fulfillment of predefined load scenarios and are at the same time robust to uncertainties in the load. Therefore, we model the electric motor and the gearbox within a Mixed-Integer Nonlinear Program, and optimize the efficiency of the mechanical parts of the powertrain. By combining this mathematical optimization program with an unsupervised machine learning algorithm, we are able to derive global-optimal gearbox designs for practically relevant momentum and speed requirements. KW - Powertrain KW - Gearbox KW - Optimization KW - BEV KW - WLTP Y1 - 2019 SN - 978-3-030-21802-7 U6 - http://dx.doi.org/10.1007/978-3-030-21803-4_91 SP - 916 EP - 925 PB - Springer CY - Cham ER - TY - CHAP A1 - Stenger, David A1 - Altherr, Lena A1 - Abel, Dirk T1 - Machine learning and metaheuristics for black-box optimization of product families: a case-study investigating solution quality vs. computational overhead T2 - Operations Research Proceedings 2018 N2 - In product development, numerous design decisions have to be made. Multi-domain virtual prototyping provides a variety of tools to assess technical feasibility of design options, however often requires substantial computational effort for just a single evaluation. A special challenge is therefore the optimal design of product families, which consist of a group of products derived from a common platform. Finding an optimal platform configuration (stating what is shared and what is individually designed for each product) and an optimal design of all products simultaneously leads to a mixed-integer nonlinear black-box optimization model. We present an optimization approach based on metamodels and a metaheuristic. To increase computational efficiency and solution quality, we compare different types of Gaussian process regression metamodels adapted from the domain of machine learning, and combine them with a genetic algorithm. We illustrate our approach on the example of a product family of electrical drives, and investigate the trade-off between solution quality and computational overhead. KW - Product family optimization KW - Mixed-integer nonlinear black-box optimization KW - Engineering optimization KW - Machine learning Y1 - 2019 SN - 978-3-030-18499-5 (Print) SN - 978-3-030-18500-8 (Online) U6 - http://dx.doi.org/10.1007/978-3-030-18500-8_47 SP - 379 EP - 385 PB - Springer CY - Cham ER - TY - CHAP A1 - Müller, Tim M. A1 - Altherr, Lena A1 - Ahola, Marja A1 - Schabel, Samuel A1 - Pelz, Peter F. T1 - Optimizing pressure screen systems in paper recycling: optimal system layout, component selection and operation N2 - Around 60% of the paper worldwide is made from recovered paper. Especially adhesive contaminants, so called stickies, reduce paper quality. To remove stickies but at the same time keep as many valuable fibers as possible, multi-stage screening systems with several interconnected pressure screens are used. When planning such systems, suitable screens have to be selected and their interconnection as well as operational parameters have to be defined considering multiple conflicting objectives. In this contribution, we present a Mixed-Integer Nonlinear Program to optimize system layout, component selection and operation to find a suitable trade-off between output quality and yield. KW - Mixed-integer nonlinear problem KW - MINLP KW - Process engineering KW - Paper recycling KW - Multi-criteria optimization Y1 - 2018 SN - 978-3-030-18499-5 U6 - http://dx.doi.org/10.1007/978-3-030-18500-8_44 SP - 355 EP - 361 PB - Springer CY - Cham ER - TY - CHAP A1 - Stenger, David A1 - Altherr, Lena A1 - Müller, Tankred A1 - Pelz, Peter F. T1 - Product family design optimization using model-based engineering techniques T2 - Operations Research Proceedings 2017 N2 - Highly competitive markets paired with tremendous production volumes demand particularly cost efficient products. The usage of common parts and modules across product families can potentially reduce production costs. Yet, increasing commonality typically results in overdesign of individual products. Multi domain virtual prototyping enables designers to evaluate costs and technical feasibility of different single product designs at reasonable computational effort in early design phases. However, savings by platform commonality are hard to quantify and require detailed knowledge of e.g. the production process and the supply chain. Therefore, we present and evaluate a multi-objective metamodel-based optimization algorithm which enables designers to explore the trade-off between high commonality and cost optimal design of single products. Y1 - 2018 SN - 978-3-319-89919-0 U6 - http://dx.doi.org/10.1007/978-3-319-89920-6_66 SP - 495 EP - 502 PB - Springer CY - Cham ER - TY - CHAP A1 - Altherr, Lena A1 - Dörig, Bastian A1 - Ederer, Thorsten A1 - Pelz, Peter Franz A1 - Pfetsch, Marc A1 - Wolf, Jan T1 - A mixed-integer nonlinear program for the design of gearboxes T2 - Operations Research Proceedings 2016 N2 - Gearboxes are mechanical transmission systems that provide speed and torque conversions from a rotating power source. Being a central element of the drive train, they are relevant for the efficiency and durability of motor vehicles. In this work, we present a new approach for gearbox design: Modeling the design problem as a mixed-integer nonlinear program (MINLP) allows us to create gearbox designs from scratch for arbitrary requirements and—given enough time—to compute provably globally optimal designs for a given objective. We show how different degrees of freedom influence the runtime and present an exemplary solution. Y1 - 2017 SN - 978-3-319-55701-4 U6 - http://dx.doi.org/10.1007/978-3-319-55702-1_31 SP - 227 EP - 233 PB - Springer CY - Cham ER - TY - CHAP A1 - Leise, Philipp A1 - Altherr, Lena A1 - Pelz, Peter F. T1 - Energy-Efficient design of a water supply system for skyscrapers by mixed-integer nonlinear programming T2 - Operations Research Proceedings 2017 N2 - 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. KW - Engineering optimization KW - Global optimization KW - Energy efficiency KW - Water KW - Network Y1 - 2018 SN - 978-3-319-89919-0 U6 - http://dx.doi.org/10.1007/978-3-319-89920-6_63 PB - Springer CY - Cham ER - TY - CHAP A1 - Timme, Michael T1 - Wettbewerbsregeln (§§ 24-27) T2 - Münchener Kommentar zum europäischen und deutschen Wettbewerbsrecht : Kartellrecht, Beihilfenrecht, Vergaberecht / hrsg von Franz Jürgen Säcker / Band 2: Deutsches Wettbewerbsrecht Gesetz gegen Wettbewerbsbeschränkungen (GWB), §§ 1-96, 185, 186 Y1 - 2022 SN - 978-3-406-75876-8 SP - 589 EP - 608 PB - Beck CY - München ER - TY - CHAP A1 - Borggrafe, Andreas A1 - Ohndorf, Andreas A1 - Dachwald, Bernd A1 - Seboldt, Wolfgang T1 - Analysis of interplanetary solar sail trajectories with attitude dynamics T2 - Dynamics and Control of Space Systems 2012 N2 - We present a new approach to the problem of optimal control of solar sails for low-thrust trajectory optimization. The objective was to find the required control torque magnitudes in order to steer a solar sail in interplanetary space. A new steering strategy, controlling the solar sail with generic torques applied about the spacecraft body axes, is integrated into the existing low-thrust trajectory optimization software InTrance. This software combines artificial neural networks and evolutionary algorithms to find steering strategies close to the global optimum without an initial guess. Furthermore, we implement a three rotational degree-of-freedom rigid-body attitude dynamics model to represent the solar sail in space. Two interplanetary transfers to Mars and Neptune are chosen to represent typical future solar sail mission scenarios. The results found with the new steering strategy are compared to the existing reference trajectories without attitude dynamics. The resulting control torques required to accomplish the missions are investigated, as they pose the primary requirements to a real on-board attitude control system. Y1 - 2012 SN - 978-0-87703-587-9 SP - 1553 EP - 1569 PB - Univelt Inc CY - San Diego ER -