TY - JOUR A1 - Nehr, Sascha A1 - Baus, Lukas A1 - Çinar, Hasan A1 - Elsen, Ingo A1 - Frauenrath, Tobias T1 - Indoor environmental quality assessment in passively ventilated classrooms in Germany and estimation of ventilation energy losses JF - Journal of Building Engineering N2 - In this field study we present an approach for the comprehensive and room-specific assessment of parameters with the overall aim to realize energy-efficient provision of hygienically harmless and thermally comfortable indoor environmental quality in naturally ventilated non-residential buildings. The approach is based on (i) conformity assessment of room design parameters, (ii) empirical determination of theoretically expected occupant-specific supply air flow rates and corresponding air exchange rates, (iii) experimental determination of real occupant-specific supply air flow rates and corresponding air exchange rates, (iv) measurement of indoor environmental exposure conditions of T, RH, cCO2 , cPM2.5 and cTVOC, and (v) determination of real energy demands for the prevailing ventilation scheme. Underlying assessment criteria comprise the indoor environmental parameters of category II of EN 16798-1: Temperature T = 20 ◦C–24 ◦C, and relative humidity RH = 25 %–60 % as well as the guide values of the German Federal Environment Agency for cCO2 cPM2.5 and cTVOC of 1000 ppm, 15 μg m⁻³, and 1 mg m ⁻³, respectively. Investigation objects are six naturally ventilated classrooms of a German secondary school. Major factors influencing indoor environmental quality in these classrooms are the specific room volume per occupant and the window opening area. It is concluded that the rigorous implementation of ventilation recommendations laid down by the German Federal Environment Agency is ineffective with respect to anticipated indoor environmental parameters and inefficient with respect to ventilation energy losses on the order of about 10 kWh m⁻² a ⁻¹ to 30 kWh m⁻² a ⁻¹. KW - Indoor air quality KW - Indoor environmental quality KW - Energy-efficient ventilation KW - CO2 KW - PM2.5 Y1 - 2024 SN - 2352-7102 VL - 97 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Harlacher, Markus A1 - Altepost, Andrea A1 - Elsen, Ingo A1 - Ferrein, Alexander A1 - Hansen-Ampah, Adjan A1 - Merx, Wolfgang A1 - Niehues, Sina A1 - Schiffer, Stefan A1 - Shahinfar, Fatemeh Nasim ED - Lausberg, Isabel ED - Vogelsang, Michael T1 - Approach for the identification of requirements on the design of AI-supported work systems (in problem-based projects) T2 - AI in Business and Economics N2 - To successfully develop and introduce concrete artificial intelligence (AI) solutions in operational practice, a comprehensive process model is being tested in the WIRKsam joint project. It is based on a methodical approach that integrates human, technical and organisational aspects and involves employees in the process. The chapter focuses on the procedure for identifying requirements for a work system that is implementing AI in problem-driven projects and for selecting appropriate AI methods. This means that the use case has already been narrowed down at the beginning of the project and must be completely defined in the following. Initially, the existing preliminary work is presented. Based on this, an overview of all procedural steps and methods is given. All methods are presented in detail and good practice approaches are shown. Finally, a reflection of the developed procedure based on the application in nine companies is given. KW - Business understanding KW - Requirements KW - Process model KW - Participation KW - Im-plementation of AI-systems Y1 - 2024 SN - 9783110790320 U6 - https://doi.org/10.1515/9783110790320 SP - 87 EP - 99 PB - De Gruyter CY - Berlin ER - TY - JOUR A1 - Sanchez-Cespedes, Lina Maria A1 - Leasure, Douglas Ryan A1 - Tejedor-Garavito, Natalia A1 - Amaya Cruz, Glenn Harry A1 - Garcia Velez, Gustavo Adolfo A1 - Mendoza Beltrán, Andryu Enrique A1 - Marín-Salazar, Yenny Andrea A1 - Esch, Thomas A1 - Tatem, Andrew J. A1 - Ospina Bohórquez, Mariana Francisca T1 - Social cartography and satellite-derived building coverage for post-census population estimates in difficult-to-access regions of Colombia JF - Population studies : a Journal of Demography N2 - Effective government services rely on accurate population numbers to allocate resources. In Colombia and globally, census enumeration is challenging in remote regions and where armed conflict is occurring. During census preparations, the Colombian National Administrative Department of Statistics conducted social cartography workshops, where community representatives estimated numbers of dwellings and people throughout their regions. We repurposed this information, combining it with remotely sensed buildings data and other geospatial data. To estimate building counts and population sizes, we developed hierarchical Bayesian models, trained using nearby full-coverage census enumerations and assessed using 10-fold cross-validation. We compared models to assess the relative contributions of community knowledge, remotely sensed buildings, and their combination to model fit. The Community model was unbiased but imprecise; the Satellite model was more precise but biased; and the Combination model was best for overall accuracy. Results reaffirmed the power of remotely sensed buildings data for population estimation and highlighted the value of incorporating local knowledge. KW - modelled population estimates KW - population and housing census KW - GIS KW - remote sensing KW - Bayesian statistics Y1 - 2023 U6 - https://doi.org/10.1080/00324728.2023.2190151 SN - 1477-4747 VL - 78 IS - 1 SP - 3 EP - 20 PB - Taylor & Francis CY - London ER - TY - JOUR A1 - Rake, Heinrich A1 - Enning, Manfred A1 - Kurth, Johannes A1 - Schröder, Walter T1 - Automatic uncoupler completes automation at the hump JF - RGI - Railway Gazette International Y1 - 1994 SN - 0373-5346 VL - 150 IS - 6 SP - 371 EP - 374 PB - Reed Business CY - Sutton ER - TY - JOUR A1 - Rake, Heinrich A1 - Schwanhäußer, Wulf A1 - Frederich, Fritz A1 - Enning, Manfred T1 - Automatisierung von Ablaufanlagen mit dem Kupplungsroboter JF - ETR - Eisenbahntechnische Rundschau Y1 - 1993 SN - 0013-2845 IS - 4 SP - 249 EP - 254 PB - DVV Media Group CY - Hamburg ER - TY - CHAP A1 - Enning, Manfred A1 - Hilgers, Rudolf ED - Nießen, Nils ED - Schindler, Christian T1 - Die Assistierte Bremsprobe als Brücke zur Vollautomatisierung des Schienengüterverkehrs T2 - IRSA 2023: Tagungsband, Proceedings Y1 - 2023 U6 - https://doi.org/10.18154/RWTH-2024-00257 N1 - 4. International Railway Symposium Aachen, 22. bis 23. November 2023, Eurogress, Aachen SP - 60 EP - 75 PB - RWTH Aachen CY - Aachen ER - TY - JOUR A1 - Manfred, Enning A1 - May, Jörg A1 - Sutter, Stefan T1 - Innovation am Güterwagen am Beispiel der Automatischen Bremsprobe JF - ETR - Eisenbahntechnische Rundschau N2 - Mit der Digitalen Automatischen Kupplung beginnt ein neues Kapitel des Schienengüterverkehrs, in dem zusammengestellte Wagen sich automatisch in wenigen Minuten abfahrbereit machen, ohne dass der Mensch eingreifen muss. Eines des größten Hemmnisse der umweltfreundlichen Schiene wird dann entfallen. Notwendig ist jetzt eine Diskussion über den Umfang und die Systemgrenzen der Automatischen Bremsprobe. Y1 - 2020 SN - 0013-2845 IS - 12 SP - 14 EP - 19 PB - DVV Media Group CY - Hamburg ER - TY - JOUR A1 - Enning, Manfred A1 - Schmidt, Bernd A1 - Wilbring, Daniela T1 - Auf dem Weg zur autonomen Anschlussbedienung JF - Privatbahn-Magazin Y1 - 2019 SN - 1865-0163 IS - 3 SP - 40 EP - 43 PB - Bahn Media CY - Suhlendorf ER - TY - CHAP A1 - Pfaff, Raphael A1 - Schmidt, Bernd A1 - Wilbring, Daniela A1 - Franzen, Julian T1 - Wagon4.0 – the smart wagon for improved integration into Industry 4.0 plants T2 - Proceedings of the International Heavy Haul Association STS Conference 2019 N2 - In many instances, freight vehicles exchange load or information with plants that are or will soon be Industry4.0 plants. The Wagon4.0 concept, as developed in close cooperation with e.g. port or mine operations, offers a maximum in railway operational efficiency while providing strong business cases already in the respective plant interaction. The Wagon4.0 consists of main components, a power supply, data network, sensors, actuators and an operating system, the so called WagonOS. The Wagon OS is implemented in a granular, self-sufficient manner, to allow basic features such as WiFi-Mesh and train christening in remote areas without network connection. Furthermore, the granularity of the operating system allows to extend the familiar app concept to freight rail rolling stock, making it possible to use specialised actuators for certain applications, e.g. an electrical parking brake or an auxiliary drive. In order to facilitate migration to the Wagon4.0 for existing fleets, a migration concept featuring five levels of technical adaptation was developed. The present paper investigates the benefits of Wagon4.0-implementations for the particular challenges of heavy haul operations by focusing on train christening, ep-assisted braking, autonomous last mile and traction boost operation as well as improved maintenance schedules Y1 - 2019 N1 - International Heavy Haul Association STS Conference, 10th to 14th June 2019, Narvik, Norway ER - TY - CHAP A1 - Wilbring, Daniela A1 - Enning, Manfred A1 - Pfaff, Raphael A1 - Schmidt, Bernd ED - de Doncker, Rik W. ED - Nießen, Nils ED - Schindler, Christian T1 - Neue Perspektiven für die Bahn in der Produktions- und Distributionslogistik durch Prozessautomation T2 - IRSA 2019: Tagungsband, Proceedings N2 - Deutschland braucht mehr Eisenbahn um CO2-Emissionen aus dem Verkehr zu reduzieren. Sie muss zum Rückgrat aktueller Logistikprozesse, z.B. bei Kaufmannsgütern und E-Commerce, werden. Dies geht nicht ohne neuartige betriebliche Konzepte und eine Transformation des Güterwagens von einem „dummen Stück Stahl“ zu einem modernen Werkzeug der Logistik. Als „Güterwagen 4.0“ wird ein kommunikativer und kooperativer Güterwagen verstanden, der die Voraussetzung zur Automatisierung aller Prozesse der Zugvorbereitung bereitstellt, sich aber ansonsten vollkommen kompatibel mit heutigen Betriebsverfahren im Hauptlauf präsentiert. Durch Kommunikation zwischen Güterwagen und umgebenden intelligenten Systemen im Sinne eines „Internet der Dinge“ gelingt damit unter Anderem die Realisierung hoch effizienter Gleisanschlussverkehre, die der Güterbahn neue Märkte abseits der klassisch bahn-affinen Verkehre erschließen und letztlich den Wandel zu einer nachhaltigen Gütermobilität fördern. Y1 - 2019 U6 - https://doi.org/10.18154/RWTH-2020-00014 N1 - 2nd International Railway Symposium Aachen, Aachen, Germany, 26 – 28 November 2019 SP - 128 EP - 142 PB - RWTH Aachen CY - Aachen ER - TY - JOUR A1 - Enning, Manfred A1 - Pfaff, Raphael T1 - Güterwagen 4.0 - Mehr als nur technischer Fortschritt JF - Privatbahn-Magazin N2 - Lokomotiven sind dank modernster Konzepte der Antriebstechnik heute energiesparend und umweltfreundlich. Eine Ausrüstung mit Telematik und Assistenzfunktionen ist Standard. Auf der Strecke zeigt sich moderne Technik in Form elektronischer Stellwerke und Zugsicherungssysteme und in Rangier- und Abstellanlagen als EOW-Technik. Am Güterwagen hingegen ist der technische Fortschritt komplett vorbeigegangen. Auch beim modernsten Wagen (Abb. 1) ist die einzige „Automatik“-Funktion die zentral über die Hauptluftleitung (HL) versorgte und betätigte Luftbremse. Y1 - 2017 SN - 1865-0163 IS - 2 SP - 21 EP - 25 PB - Bahn Media CY - Suhlendorf ER - TY - JOUR A1 - Enning, Manfred A1 - Pfaff, Raphael T1 - Digitalisierung bringt mehr Güter auf die Schiene JF - Sonderprojekte ATM/MTZ Y1 - 2016 U6 - https://doi.org/10.1007/s41491-016-0570-7 SN - 2509-4610 VL - 21 IS - 6 (suppl.) SP - 34 EP - 37 PB - Springer Fachmedien CY - Wiesbaden ER - TY - CHAP A1 - Stark, Ralf A1 - Bartel, Sebastian A1 - Ditsche, Florian A1 - Esch, Thomas T1 - Design study of a 30kN LOX/LCH4 aerospike rocket engine for lunar lander application T2 - Aerospace Europe Conference 2023 - 10th EUCASS - 9th CEAS N2 - Based on lunar lander concept EL3, various LOX/CH4 aerospike engines were studied. A distinction was made between single and cluster configurations as well as ideal and non-ideal contour concepts. It could be shown that non-ideal aerospike engines promise a significant payload gain. Y1 - 2023 N1 - Lausanne, July 9-13, 2023 ER - TY - CHAP A1 - Stark, Ralf A1 - Rieping, Carla A1 - Esch, Thomas T1 - The impact of guide tubes on flow separation in rocket nozzles T2 - Aerospace Europe Conference 2023 - 10th EUCASS - 9th CEAS N2 - Rocket engine test facilities and launch pads are typically equipped with a guide tube. Its purpose is to ensure the controlled and safe routing of the hot exhaust gases. In addition, the guide tube induces a suction that effects the nozzle flow, namely the flow separation during transient start-up and shut-down of the engine. A cold flow subscale nozzle in combination with a set of guide tubes was studied experimentally to determine the main influencing parameters. KW - Guide Tube KW - TICTOP KW - Nozzle KW - Suction Y1 - 2023 N1 - Lausanne, July 9-13, 2023 ER - TY - JOUR A1 - Schopen, Oliver A1 - Narayan, Sriram A1 - Beckmann, Marvin A1 - Najmi, Aezid-Ul-Hassan A1 - Esch, Thomas A1 - Shabani, Bahman T1 - An EIS approach to quantify the effects of inlet air relative humidity on the performance of proton exchange membrane fuel cells: a pathway to developing a novel fault diagnostic method JF - International Journal of Hydrogen Energy N2 - In this work, the effect of low air relative humidity on the operation of a polymer electrolyte membrane fuel cell is investigated. An innovative method through performing in situ electrochemical impedance spectroscopy is utilised to quantify the effect of inlet air relative humidity at the cathode side on internal ionic resistances and output voltage of the fuel cell. In addition, algorithms are developed to analyse the electrochemical characteristics of the fuel cell. For the specific fuel cell stack used in this study, the membrane resistance drops by over 39 % and the cathode side charge transfer resistance decreases by 23 % after increasing the humidity from 30 % to 85 %, while the results of static operation also show an increase of ∼2.2 % in the voltage output after increasing the relative humidity from 30 % to 85 %. In dynamic operation, visible drying effects occur at < 50 % relative humidity, whereby the increase of the air side stoichiometry increases the drying effects. Furthermore, other parameters, such as hydrogen humidification, internal stack structure, and operating parameters like stoichiometry, pressure, and temperature affect the overall water balance. Therefore, the optimal humidification range must be determined by considering all these parameters to maximise the fuel cell performance and durability. The results of this study are used to develop a health management system to ensure sufficient humidification by continuously monitoring the fuel cell polarisation data and electrochemical impedance spectroscopy indicators. KW - PEM fuel cell KW - Electrochemical impedance spectroscopy KW - Relative air humidity KW - Active humidity control KW - Impedance analysis Y1 - 2024 SN - 0360-3199 (print) U6 - https://doi.org/10.1016/j.ijhydene.2024.01.218 SN - 1879-3487 (online) VL - 58 IS - 8 SP - 1302 EP - 1315 PB - Elsevier CY - Amsterdam ER - TY - GEN A1 - Machado, Patricia Almeida A1 - Dahmann, Peter A1 - Keimer, Jona A1 - Saretzki, Charlotte A1 - Stübing, Felix A1 - Küpper, Thomas T1 - Stress profile and individual workload monitoring in general aviation pilots – an experiment’s setting T2 - 23. Annual Meeting of the German Society of Travel Medicine, Coburg, 18.-19.9.2020 Y1 - 2020 U6 - https://doi.org/10.55225/hppa.156 ER - TY - GEN A1 - Mayntz, Joscha A1 - Keimer, Jona A1 - Tegtmeyer, Philipp A1 - Dahmann, Peter A1 - Hille, Sebastian A1 - Stumpf, Eike A1 - Fisher, Alex A1 - Dorrington, Graham T1 - Aerodynamic Investigation on Efficient Inflight Transition of a Propeller from Propulsion to Regeneration Mode T2 - AIAA SCITECH 2022 Forum N2 - This paper discusses a new way of inflight power regeneration for electric or hybrid-electric driven general aviation aircraft with one powertrain for both configurations. Three different approaches for the shift from propulsion to regeneration mode are analyzed. Numerical cal-culation and wind tunnel results are compared and show the highest regeneration potential for the "Windmill" approach, where the propeller blades are flipped, and rotation is reversed. A combination of all regeneration approaches for a realistic flight mission is discussed. Y1 - 2021 U6 - https://doi.org/10.2514/6.2022-0546 N1 - AIAA SCITECH 2022 Forum, January 3-7, 2022, San Diego, CA & Virtual PB - AIAA CY - Reston, Va. ER - TY - JOUR A1 - Saretzki, Charlotte A1 - Bergmann, Ole A1 - Dahmann, Peter A1 - Janser, Frank A1 - Keimer, Jona A1 - Machado, Patricia A1 - Morrison, Audry A1 - Page, Henry A1 - Pluta, Emil A1 - Stübing, Felix A1 - Küpper, Thomas T1 - Are small airplanes safe with regards to COVID-19 transmission? JF - Journal of Travel Medicine Y1 - 2021 U6 - https://doi.org/10.1093/jtm/taab105 SN - 1708-8305 VL - 28 IS - 7 PB - Oxford University Press CY - Oxford ER - TY - GEN A1 - Keimer, Jona A1 - Girbig, Leo A1 - Mayntz, Joscha A1 - Tegtmeyer, Philipp A1 - Wendland, Frederik A1 - Dahman, Peter A1 - Fisher, Alex A1 - Dorrington, Graham T1 - Flight mission optimization for eco-efficiency in consideration of electric regeneration and atmospheric conditions T2 - AIAA AVIATION 2022 Forum N2 - The development and operation of hybrid or purely electrically powered aircraft in regional air mobility is a significant challenge for the entire aviation sector. This technology is expected to lead to substantial advances in flight performance, energy efficiency, reliability, safety, noise reduction, and exhaust emissions. Nevertheless, any consumed energy results in heat or carbon dioxide emissions and limited electric energy storage capabilities suppress commercial use. Therefore, the significant challenges to achieving eco-efficient aviation are increased aircraft efficiency, the development of new energy storage technologies, and the optimization of flight operations. Two major approaches for higher eco-efficiency are identified: The first one, is to take horizontal and vertical atmospheric motion phenomena into account. Where, in particular, atmospheric waves hold exciting potential. The second one is the use of the regeneration ability of electric aircraft. The fusion of both strategies is expected to improve efficiency. The objective is to reduce energy consumption during flight while not neglecting commercial usability and convenient flight characteristics. Therefore, an optimized control problem based on a general aviation class aircraft has to be developed and validated by flight experiments. The formulated approach enables a development of detailed knowledge of the potential and limitations of optimizing flight missions, considering the capability of regeneration and atmospheric influences to increase efficiency and range. Y1 - 2022 U6 - https://doi.org/10.2514/6.2022-4118 N1 - AIAA AVIATION 2022 Forum, June 27-July 1, 2022 Chicago, IL & Virtual PB - AIAA CY - Reston, Va. ER - TY - JOUR A1 - Thoma, Andreas A1 - Gardi, Alessandro A1 - Fisher, Alex A1 - Braun, Carsten T1 - Improving local path planning for UAV flight in challenging environments by refining cost function weights JF - CEAS Aeronautical Journal N2 - Unmanned Aerial Vehicles (UAV) constantly gain in versatility. However, more reliable path planning algorithms are required until full autonomous UAV operation is possible. This work investigates the algorithm 3DVFH* and analyses its dependency on its cost function weights in 2400 environments. The analysis shows that the 3DVFH* can find a suitable path in every environment. However, a particular type of environment requires a specific choice of cost function weights. For minimal failure, probability interdependencies between the weights of the cost function have to be considered. This dependency reduces the number of control parameters and simplifies the usage of the 3DVFH*. Weights for costs associated with vertical evasion (pitch cost) and vicinity to obstacles (obstacle cost) have the highest influence on the failure probability of the local path planner. Environments with mainly very tall buildings (like large American city centres) require a preference for horizontal avoidance manoeuvres (achieved with high pitch cost weights). In contrast, environments with medium-to-low buildings (like European city centres) benefit from vertical avoidance manoeuvres (achieved with low pitch cost weights). The cost of the vicinity to obstacles also plays an essential role and must be chosen adequately for the environment. Choosing these two weights ideal is sufficient to reduce the failure probability below 10%. KW - Bio-inspired systems KW - Path planning KW - Obstacle avoidance KW - Unmanned aerial vehicles Y1 - 2024 U6 - https://doi.org/10.1007/s13272-024-00741-x SN - 1869-5590 (eISSN) SN - 1869-5582 N1 - Corresponding author: Andreas Thoma PB - Springer CY - Wien ER -