TY - JOUR A1 - Alexopoulos, Spiros A1 - Hoffschmidt, Bernhard T1 - Solar tower power plant in Germany and future perspectives of the development of the technology in Greece and Cyprus JF - Renewable Energy . 35 (2010), H. 7 Y1 - 2010 SN - 0960-1481 SP - 1352 EP - 1356 ER - TY - CHAP A1 - Kob, Malte A1 - Butenweg, Christoph T1 - A finite element model of the interaction between intra-and extralaryngeal muscles T2 - International Conference on Voice Physiology and Biomechanics, August 18-20, 2004, Marseille, France Y1 - 2004 SP - 1 EP - 2 ER - TY - CHAP A1 - Dalguer, Luis A. A1 - Renault, Philippe A1 - Churilov, Sergey A1 - Butenweg, Christoph T1 - Evaluation of fragility curves for a three-storey-reinforced-concrete mock-up of SMART 2013 project T2 - Transactions, SMiRT-23 : 23rd Conference on Structural Mechanics in Reactor Technology : Manchester, United Kingdom - August 10-14, 2015 Y1 - 2016 SP - 1 EP - 9 ER - TY - CHAP A1 - Giresini, Linda A1 - Butenweg, Christoph T1 - Earthquake resistant design of structures according to Eurocode 8 T2 - Structural Dynamics with Applications in Earthquake and Wind Engineering N2 - The chapter initially provides a summary of the contents of Eurocode 8, its aim being to offer both to the students and to practising engineers an easy introduction into the calculation and dimensioning procedures of this earthquake code. Specifically, the general rules for earthquake-resistant structures, the definition of design response spectra taking behaviour and importance factors into account, the application of linear and non-linear calculation methods and the structural safety verifications at the serviceability and ultimate limit state are presented. The application of linear and non-linear calculation methods and corresponding seismic design rules is demonstrated on practical examples for reinforced concrete, steel and masonry buildings. Furthermore, the seismic assessment of existing buildings is discussed and illustrated on the example of a typical historical masonry building in Italy. The examples are worked out in detail and each step of the design process, from the preliminary analysis to the final design, is explained in detail. KW - Seismic design KW - Eurocode 8 KW - Design examples KW - Response spectrum KW - Pushover analysis Y1 - 2019 SN - 978-3-662-57550-5 (Online) SN - 978-3-662-57548-2 (Print) U6 - https://doi.org/10.1007/978-3-662-57550-5_4 SP - 197 EP - 358 PB - Springer CY - Berlin ER - TY - CHAP A1 - Kalker, Ines A1 - Toll, B. A1 - Holler, Stefan A1 - Butenweg, Christoph A1 - Topping, B. H. V. A1 - Mota Soares, C. A. T1 - Capacity analysis of textile retrofitted unreinforced masonry T2 - Proceedings of the Seventh International Conference on Computational Structures Technology : [Lisbon, Portugal, 7 - 9 September 2004] / ed. by B. H. V. Topping ... Y1 - 2004 SN - 0-948749-95-4 U6 - https://doi.org/10.4203/ccp.79.194 SP - 431 EP - 432 PB - Civil-Comp Press CY - Stirling ER - TY - JOUR A1 - Butenweg, Christoph A1 - Rosin, Julia A1 - Holler, Stefan T1 - Analysis of cylindrical granular material silos under seismic excitation JF - Buildings N2 - Silos generally work as storage structures between supply and demand for various goods, and their structural safety has long been of interest to the civil engineering profession. This is especially true for dynamically loaded silos, e.g., in case of seismic excitation. Particularly thin-walled cylindrical silos are highly vulnerable to seismic induced pressures, which can cause critical buckling phenomena of the silo shell. The analysis of silos can be carried out in two different ways. In the first, the seismic loading is modeled through statically equivalent loads acting on the shell. Alternatively, a time history analysis might be carried out, in which nonlinear phenomena due to the filling as well as the interaction between the shell and the granular material are taken into account. The paper presents a comparison of these approaches. The model used for the nonlinear time history analysis considers the granular material by means of the intergranular strain approach for hypoplasticity theory. The interaction effects between the granular material and the shell is represented by contact elements. Additionally, soil–structure interaction effects are taken into account. KW - granular silo KW - earthquake engineering KW - hypoplasticity KW - nonlinear transient analyses Y1 - 2017 U6 - https://doi.org/10.3390/buildings7030061 SN - 2075-5309 VL - 7 IS - 3 SP - 1 EP - 12 PB - MDPI CY - Basel ER - TY - CHAP A1 - Giresini, Linda A1 - Butenweg, Christoph A1 - Andreini, M. A1 - De Falco, A. A1 - Sassu, M. T1 - Macro-elements identification in historic chapels: the case of St. Venerio Chapel in Reggiolo - Emilia Romagna T2 - 9th International Conference on Structural Analyses of Historical Conctruction, 14 - 17 October, 2014, Mexico City Y1 - 2014 SP - 1 EP - 12 ER - TY - CHAP A1 - Meskouris, Konstantin A1 - Holler, Stefan A1 - Butenweg, Christoph A1 - Meiners, Daniel T1 - A multiphase model with hypoplastic formulation of the solid phase and its application to earthquake engineering problems T2 - Computational structural dynamics and earthquake engineering / ed. by Manolis Papadrakakis .... (Structures and infrastructures series ; 2) Y1 - 2009 SN - 978-0-415-45261-8 U6 - https://doi.org/10.1201/9780203881637.ch19 SP - 293 EP - 308 PB - CRC Press CY - Boca Raton, Fla. [u.a.] ER - TY - CHAP A1 - Rajan, Sreelakshmy A1 - Holtschoppen, B. A1 - Dalguer, L. A. A1 - Klinkel, S. A1 - Butenweg, Christoph ED - Sas, P. T1 - Seismic fragility analysis of a non-conventional reinforced concrete structure considering different uncertainties T2 - Proceedings of ISMA2016, International Conference on Noise and Vibration Engineering/USD2016, International Conference on Uncertainty in Structural Dynamics, / ISMA 2016, USD 2016 Y1 - 2016 SP - 4213 EP - 4225 PB - KU Leuven CY - Leuven ER - TY - JOUR A1 - Steuer-Dankert, Linda A1 - Sharma, Mamta Rameshwarlal A1 - Bleck, Wolfgang A1 - Leicht-Scholten, Carmen T1 - Diversity and innovation management in large research groups JF - International Journal of Innovation Management N2 - Contemporary research appreciates a diverse workforce as a potential source of innovation. Researchers explore the fine details of why diversity management is central for generating innovations in heterogeneous research groups and how it could be effectively implemented into organizations. Complex research associations that discuss topics with a high impact on society increasingly address the necessity of establishing a diverse workforce to confront the challenges of tomorrow. Characterized by complex management structures as well as hierarchies, research associations have not been a subject of investigation until now. For this reason, the presented research project aims to develop a diversity and innovation management strategy with the ultimate goal of inducing change in the corporate culture. The proposed approach consisted of six phases; the first two phases investigated the status quo of diversity in the existing organizational structures of member institutes and the variety of particular working cultures within the research association. The third and the fourth phases utilized qualitative and quantitative studies. The third phase focused on the connection of management level to diversity and innovation, and the need for diversity and innovation management, and tailor-made methods of implementing them. The first three phases have been accomplished successfully; preliminary results are already available. The fourth phase will mainly focus on exploring the mind-set of the employees. The fifth phase will consolidate the findings in the first four phases into an implementable strategy. The final phase will address the implementation of this strategy into the organization. Phases 4 to 6 have not yet been undertaken KW - diversity management KW - innovation management KW - research association KW - change management KW - engineering Y1 - 2017 SN - 1757-5877 VL - 5 IS - 2 SP - 49 EP - 72 ER - TY - JOUR A1 - Steuer-Dankert, Linda A1 - Gilmartin, Shannon K. A1 - Muller, Carol B. A1 - Dungs, Carolin A1 - Sheppard, Sheri A1 - Leicht-Scholten, Carmen T1 - Expanding engineering limits : a concept for socially responsible education of engineers JF - The international journal of engineering education Y1 - 2019 SN - 0949-149X VL - 35 IS - 2 SP - 658 EP - 673 ER - TY - JOUR A1 - Blanke, Tobias A1 - Hagenkamp, Markus A1 - Döring, Bernd A1 - Göttsche, Joachim A1 - Reger, Vitali A1 - Kuhnhenne, Markus T1 - Net-exergetic, hydraulic and thermal optimization of coaxial heat exchangers using fixed flow conditions instead of fixed flow rates JF - Geothermal Energy N2 - Previous studies optimized the dimensions of coaxial heat exchangers using constant mass fow rates as a boundary condition. They show a thermal optimal circular ring width of nearly zero. Hydraulically optimal is an inner to outer pipe radius ratio of 0.65 for turbulent and 0.68 for laminar fow types. In contrast, in this study, fow conditions in the circular ring are kept constant (a set of fxed Reynolds numbers) during optimization. This approach ensures fxed fow conditions and prevents inappropriately high or low mass fow rates. The optimization is carried out for three objectives: Maximum energy gain, minimum hydraulic efort and eventually optimum net-exergy balance. The optimization changes the inner pipe radius and mass fow rate but not the Reynolds number of the circular ring. The thermal calculations base on Hellström’s borehole resistance and the hydraulic optimization on individually calculated linear loss of head coefcients. Increasing the inner pipe radius results in decreased hydraulic losses in the inner pipe but increased losses in the circular ring. The net-exergy diference is a key performance indicator and combines thermal and hydraulic calculations. It is the difference between thermal exergy fux and hydraulic efort. The Reynolds number in the circular ring is instead of the mass fow rate constant during all optimizations. The result from a thermal perspective is an optimal width of the circular ring of nearly zero. The hydraulically optimal inner pipe radius is 54% of the outer pipe radius for laminar fow and 60% for turbulent fow scenarios. Net-exergetic optimization shows a predominant infuence of hydraulic losses, especially for small temperature gains. The exact result depends on the earth’s thermal properties and the fow type. Conclusively, coaxial geothermal probes’ design should focus on the hydraulic optimum and take the thermal optimum as a secondary criterion due to the dominating hydraulics. Y1 - 2021 U6 - https://doi.org/10.1186/s40517-021-00201-3 SN - 2195-9706 N1 - Corresponding author: Tobias Blanke VL - 9 IS - Article number: 19 PB - Springer CY - Berlin ER - TY - CHAP A1 - Duran Paredes, Ludwin A1 - Mottaghy, Darius A1 - Herrmann, Ulf A1 - Groß, Rolf Fritz T1 - Online ground temperature and soil moisture monitoring of a shallow geothermal system with non-conventional components T2 - EGU General Assembly 2020 N2 - We present first results from a newly developed monitoring station for a closed loop geothermal heat pump test installation at our campus, consisting of helix coils and plate heat exchangers, as well as an ice-store system. There are more than 40 temperature sensors and several soil moisture content sensors distributed around the system, allowing a detailed monitoring under different operating conditions.In the view of the modern development of renewable energies along with the newly concepts known as Internet of Things and Industry 4.0 (high-tech strategy from the German government), we created a user-friendly web application, which will connect the things (sensors) with the open network (www). Besides other advantages, this allows a continuous remote monitoring of the data from the numerous sensors at an arbitrary sampling rate.Based on the recorded data, we will also present first results from numerical simulations, taking into account all relevant heat transport processes.The aim is to improve the understanding of these processes and their influence on the thermal behavior of shallow geothermal systems in the unsaturated zone. This will in turn facilitate the prediction of the performance of these systems and therefore yield an improvement in their dimensioning when designing a specific shallow geothermal installation. Y1 - 2020 N1 - EGU General Assembly 2020, Online, 4–8 May 2020 ER - TY - CHAP A1 - Steuer-Dankert, Linda A1 - Leicht-Scholten, Carmen T1 - Innovation and Diversity : Integrating new perspectives into research associations T2 - 12th European Conference on Innovation and Entrepreneurship (ECIE 2017) : Paris, France, 21-22 September 2017 N2 - The link between diversity and innovation is broadly discussed in the context of research and innovation processes. Many institutions and enterprises, specifically in commerce, have already tried to establish sustainable diversity management concepts, in order to increase the diversity of their workforce in addition to establishing a corporate culture of openness. Alongside the creation of a working place where different experiences and skills are valued equally, the entrepreneurial intention is to transfer diversity into economically relevant advantages. Taking into account the potential of diversity in research and innovation processes, the project “Diversity- and Innovation Management” was incorporated within a large interdisciplinary research Cluster. The project’s purpose was to study the context between diversity and innovation in research associations and to later develop a customised management concept into an interdisciplinary research Cluster on integrative production technology with full integration. The challenge of such research associations lays in an organisational structure which is often described as being decentralised. Researchers coming from different academic disciplines, while having diverse habits, conduct research on large scientific issues and challenges. In addition, these researchers are socialised in different institutions and university chairs. Theses differences in leadership styles, business cultures and organisational strategies, follow into their research team work. Taking a closer look into the management of human resources suggests that decentral organised recruitment processes, as well as allocation of human resources, lead to a lacking overview in regard to missing competencies, perspectives and backgrounds in research networks. These circumstances are comparable to big corporate groups. While developing a management concept for research associations, these characteristics must be considered. To ensure this, the project follows a human-centred approach, which considers top-down, as well as bottom-up perspectives. This paper presents the applied mixed-method approach in the scientific issue described above. In the frame of the Cluster of Excellence “Integrative Production Technology for High-Wage Countries” research results based on quantitative, as well as qualitative studies, were presented as an application example. This paper provides a new perspective on the innovation and diversity context. Against the background of complex research organisations, the development approach of a management concept is particularly interesting. KW - Innovation KW - Diversity KW - Innovation Management KW - Diversity Management KW - Leadership Y1 - 2017 SN - 978-1-911218-54-8 SP - 767 EP - 776 ER - TY - CHAP A1 - Mahdi, Zahra A1 - Dersch, Jürgen A1 - Schmitz, Pascal A1 - Dieckmann, Simon A1 - Chico Caminos, Ricardo Alexander A1 - Teixeira Boura, Cristiano José A1 - Herrmann, Ulf A1 - Schwager, Christian A1 - Schmitz, Mark A1 - Gielen, Hans A1 - Gedle, Yibekal A1 - Büscher, Rauno T1 - Technical assessment of Brayton cycle heat pumps for the integration in hybrid PV-CSP power plants T2 - SOLARPACES 2020 N2 - The hybridization of Concentrated Solar Power (CSP) and Photovoltaics (PV) systems is a promising approach to reduce costs of solar power plants, while increasing dispatchability and flexibility of power generation. High temperature heat pumps (HT HP) can be utilized to boost the salt temperature in the thermal energy storage (TES) of a Parabolic Trough Collector (PTC) system from 385 °C up to 565 °C. A PV field can supply the power for the HT HP, thus effectively storing the PV power as thermal energy. Besides cost-efficiently storing energy from the PV field, the power block efficiency of the overall system is improved due to the higher steam parameters. This paper presents a technical assessment of Brayton cycle heat pumps to be integrated in hybrid PV-CSP power plants. As a first step, a theoretical analysis was carried out to find the most suitable working fluid. The analysis included the fluids Air, Argon (Ar), Nitrogen (N2) and Carbon dioxide (CO2). N2 has been chosen as the optimal working fluid for the system. After the selection of the ideal working medium, different concepts for the arrangement of a HT HP in a PV-CSP hybrid power plant were developed and simulated in EBSILON®Professional. The concepts were evaluated technically by comparing the number of components required, pressure losses and coefficient of performance (COP). KW - Solar thermal technologies KW - Hybrid energy system KW - Concentrated solar power KW - Power plants KW - Energy storage Y1 - 2022 SN - 978-0-7354-4195-8 U6 - https://doi.org/10.1063/5.0086269 SN - 1551-7616 (online) SN - 0094-243X (print) N1 - SOLARPACES 2020: 26th International Conference on Concentrating Solar Power and Chemical Energy Systems, 28 September–2 October 2020, Freiburg, Germany IS - 2445 / 1 PB - AIP conference proceedings / American Institute of Physics CY - Melville, NY ER - TY - CHAP A1 - Mertens, Alexander A1 - Pütz, Sebastian A1 - Brauner, Philipp A1 - Brillowski, Florian Sascha A1 - Buczak, Nadine A1 - Dammers, Hannah A1 - van Dyck, Marc A1 - Kong, Iris A1 - Königs, Peter A1 - Kortomeikel, Frauke Carole A1 - Rodemann, Niklas A1 - Schaar, Anne Kathrin A1 - Steuer-Dankert, Linda A1 - Wlecke, Shari A1 - Gries, Thomas A1 - Leicht-Scholten, Carmen A1 - Nagel, Saskia K. A1 - Piller, Frank Thomas A1 - Schuh, Günther A1 - Ziefle, Martina A1 - Nitsch, Verena T1 - Human digital shadow: Data-based modeling of users and usage in the internet of production T2 - 14th Conference Human System Interaction Conference Proceedings N2 - Digital Shadows as the aggregation, linkage and abstraction of data relating to physical objects are a central vision for the future of production. However, the majority of current research takes a technocentric approach, in which the human actors in production play a minor role. Here, the authors present an alternative anthropocentric perspective that highlights the potential and main challenges of extending the concept of Digital Shadows to humans. Following future research methodology, three prospections that illustrate use cases for Human Digital Shadows across organizational and hierarchical levels are developed: human-robot collaboration for manual work, decision support and work organization, as well as human resource management. Potentials and challenges are identified using separate SWOT analyses for the three prospections and common themes are emphasized in a concluding discussion. KW - digital shadow KW - cyber physical production system KW - user & usage KW - internet of production Y1 - 2021 U6 - https://doi.org/10.1109/HSI52170.2021.9538729 N1 - 14th International Conference on Human System Interaction : 8-10 July 2021. Gdańsk, Poland SP - 1 EP - 8 PB - IEEE ER - TY - CHAP A1 - Zahra, Mahdi A1 - Phani Srujan, Merige A1 - Chico Caminos, Ricardo Alexander A1 - Schmitz, Pascal A1 - Herrmann, Ulf A1 - Teixeira Boura, Cristiano José A1 - Schmitz, Mark A1 - Gielen, Hans A1 - Gedle, Yibekal A1 - Dersch, Jürgen T1 - Modeling the thermal behavior of solar salt in electrical resistance heaters for the application in PV-CSP hybrid power plants T2 - SOLARPACES 2020 N2 - Concentrated Solar Power (CSP) systems are able to store energy cost-effectively in their integrated thermal energy storage (TES). By intelligently combining Photovoltaics (PV) systems with CSP, a further cost reduction of solar power plants is expected, as well as an increase in dispatchability and flexibility of power generation. PV-powered Resistance Heaters (RH) can be deployed to raise the temperature of the molten salt hot storage from 385 °C up to 565 °C in a Parabolic Trough Collector (PTC) plant. To avoid freezing and decomposition of molten salt, the temperature distribution in the electrical resistance heater is investigated in the present study. For this purpose, a RH has been modeled and CFD simulations have been performed. The simulation results show that the hottest regions occur on the electric rod surface behind the last baffle. A technical optimization was performed by adjusting three parameters: Shell-baffle clearance, electric rod-baffle clearance and number of baffles. After the technical optimization was carried out, the temperature difference between the maximum temperature and the average outlet temperature of the salt is within the acceptable limits, thus critical salt decomposition has been avoided. Additionally, the CFD simulations results were analyzed and compared with results obtained with a one-dimensional model in Modelica. KW - Solar thermal technologies KW - Hybrid energy system KW - Concentrated solar power KW - Energy storage KW - Photovoltaics Y1 - 2022 SN - 978-0-7354-4195-8 U6 - https://doi.org/10.1063/5.0086268 SN - 1551-7616 (online) SN - 0094-243X (print) N1 - SOLARPACES 2020: 26th International Conference on Concentrating Solar Power and Chemical Energy Systems, 28 September–2 October 2020, Freiburg, Germany IS - 2445 / 1 PB - AIP conference proceedings / American Institute of Physics CY - Melville, NY ER - TY - JOUR A1 - Rossi, Leonardo A1 - Winands, Mark H. M. A1 - Butenweg, Christoph ED - Zhang, Jessica T1 - Monte Carlo Tree Search as an intelligent search tool in structural design problems JF - Engineering with Computers : An International Journal for Simulation-Based Engineering N2 - Monte Carlo Tree Search (MCTS) is a search technique that in the last decade emerged as a major breakthrough for Artificial Intelligence applications regarding board- and video-games. In 2016, AlphaGo, an MCTS-based software agent, outperformed the human world champion of the board game Go. This game was for long considered almost infeasible for machines, due to its immense search space and the need for a long-term strategy. Since this historical success, MCTS is considered as an effective new approach for many other scientific and technical problems. Interestingly, civil structural engineering, as a discipline, offers many tasks whose solution may benefit from intelligent search and in particular from adopting MCTS as a search tool. In this work, we show how MCTS can be adapted to search for suitable solutions of a structural engineering design problem. The problem consists of choosing the load-bearing elements in a reference reinforced concrete structure, so to achieve a set of specific dynamic characteristics. In the paper, we report the results obtained by applying both a plain and a hybrid version of single-agent MCTS. The hybrid approach consists of an integration of both MCTS and classic Genetic Algorithm (GA), the latter also serving as a term of comparison for the results. The study’s outcomes may open new perspectives for the adoption of MCTS as a design tool for civil engineers. KW - Monte Carlo Tree Search KW - Structural design KW - Artificial intelligence KW - Civil engineering KW - Genetic algorithm Y1 - 2022 U6 - https://doi.org/10.1007/s00366-021-01338-2 SN - 1435-5663 SN - 0177-0667 VL - 38 IS - 4 SP - 3219 EP - 3236 PB - Springer Nature CY - Cham ER - TY - CHAP A1 - Breitbach, Gerd A1 - Alexopoulos, Spiros A1 - May, Martin A1 - Teixeira Boura, Cristiano José A1 - Herrmann, Ulf T1 - Analysis of volumetric solar radiation absorbers made of wire meshes T2 - AIP Conference Proceedings Y1 - 2019 U6 - https://doi.org/10.1063/1.5117521 SN - 0094243X VL - 2126 SP - 030009-1 EP - 030009-6 ER - TY - CHAP A1 - Philipp, Brauner A1 - Brillowski, Florian Sascha A1 - Dammers, Hannah A1 - Königs, Peter A1 - Kordtomeikel, Frauke Carole A1 - Petruck, Henning A1 - Schaar, Anne Kathrin A1 - Schmitz, Seth A1 - Steuer-Dankert, Linda A1 - Mertens, Alexander A1 - Gries, Thomas A1 - Leicht-Scholten, Carmen A1 - Nagel, Saskia K. A1 - Nitsch, Verena A1 - Schuh, Günther A1 - Ziefle, Martina ED - Mrugalska, Beata ED - Trzcielinski, Stefan ED - Karwowski, Waldemar ED - Nicolantonio, Massimo Di ED - Roossi, Emilio T1 - A research framework for human aspects in the internet of production: an intra-company perspective T2 - Proceedings of the AHFE 2020 N2 - Digitalization in the production sector aims at transferring concepts and methods from the Internet of Things (IoT) to the industry and is, as a result, currently reshaping the production area. Besides technological progress, changes in work processes and organization are relevant for a successful implementation of the “Internet of Production” (IoP). Focusing on the labor organization and organizational procedures emphasizes to consider intra-company factors such as (user) acceptance, ethical issues, and ergonomics in the context of IoP approaches. In the scope of this paper, a research approach is presented that considers these aspects from an intra-company perspective by conducting studies on the shop floor, control level and management level of companies in the production area. Focused on four central dimensions—governance, organization, capabilities, and interfaces—this contribution presents a research framework that is focused on a systematic integration and consideration of human aspects in the realization of the IoP. KW - Human factors KW - Digitalization KW - Acceptance KW - Ethics KW - Human-robot collaboration Y1 - 2020 SN - 978-3-030-51980-3 U6 - https://doi.org/10.1007/978-3-030-51981-0_1 N1 - AHFE 2020 Virtual Conferences on Human Aspects of Advanced Manufacturing, Advanced Production Management and Process Control, and Additive Manufacturing, Modeling Systems and 3D Prototyping, July 16–20, 2020, USA SP - 3 EP - 17 PB - Springer CY - Cham ER -