TY - CHAP A1 - Hoffschmidt, Bernhard A1 - Alexopoulos, Spiros A1 - Göttsche, Joachim A1 - Sauerborn, Markus A1 - Kaufhold, O. T1 - High Concentration Solar Collectors T2 - Comprehensive Renewable Energy (Second Edition) / Volume 3: Solar Thermal Systems: Components and Applications N2 - Solar thermal concentrated power is an emerging technology that provides clean electricity for the growing energy market. To the solar thermal concentrated power plant systems belong the parabolic trough, the Fresnel collector, the solar dish, and the central receiver system. For high-concentration solar collector systems, optical and thermal analysis is essential. There exist a number of measurement techniques and systems for the optical and thermal characterization of the efficiency of solar thermal concentrated systems. For each system, structure, components, and specific characteristics types are described. The chapter presents additionally an outline for the calculation of system performance and operation and maintenance topics. One main focus is set to the models of components and their construction details as well as different types on the market. In the later part of this article, different criteria for the choice of technology are analyzed in detail. KW - Central receiver system KW - Concentrated solar collector KW - Solar dish KW - Solar concentration Y1 - 2022 SN - 978-0-12-819734-9 U6 - https://doi.org/10.1016/B978-0-12-819727-1.00058-3 SP - 198 EP - 245 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Duffner, Markus A1 - Uibel, Thomas A1 - Peterson, Leif Arne A1 - Moorkamp, Wilfried ED - Fouad, Nabil A. T1 - Cross Layers Light – Ein ressourceneffizientes und recyclebares Holz-Wandsystem T2 - Bauphysik Kalender 2023: Nachhaltigkeit N2 - Ein neues tragendes, lagenweise aufgebautes Holzbau-Wandsystem und seine ökonomische und statische Entwicklung werden vorgestellt. Randbedingungen wie Nachhaltigkeit, Ressourceneffizienz und eine beanspruchungsadaptive Konstruktionsweise sind für diese innovative Bauteilentwicklung von zentraler Bedeutung. Eine wesentliche Herausforderung ist die Herstellung der Verbindung der Lagen untereinander zu einem bauphysikalisch und statisch leistungsfähigen Wandsystem. Die Tragfähigkeit und Steifigkeit verschiedener Verbindungsvarianten wurden ebenso wie die Eigenschaften der Wandelemente analytisch, numerisch und experimentell untersucht. Y1 - 2023 SN - 9783433033890 (Print) SN - 9783433611289 (Online) U6 - https://doi.org/10.1002/9783433611289.ch13 SP - 483 EP - 501 PB - Ernst & Sohn CY - Berlin ER - TY - CHAP A1 - Sattler, Johannes Christoph A1 - Chico Caminos, Ricardo Alexander A1 - Atti, Vikrama Naga Babu A1 - Ürlings, Nicolas A1 - Dutta, Siddharth A1 - Ruiz, Victor A1 - Kalogirou, Soteris A1 - Ktistis, Panayiotis A1 - Agathokleous, Rafaela A1 - Alexopoulos, Spiros A1 - Teixeira Boura, Cristiano José A1 - Herrmann, Ulf T1 - Dynamic simulation tool for a performance evaluation and sensitivity study of a parabolic trough collector system with concrete thermal energy storage T2 - AIP Conference Proceedings 2303 Y1 - 2020 U6 - https://doi.org/10.1063/5.0029277 SN - 0094-243X N1 - SOLARPACES 2019: International Conference on Concentrating Solar Power and Chemical Energy Systems, 1–4 October 2019, Daegu, South Korea SP - 160004 PB - American Institute of Physics CY - Melville, NY ER - TY - THES A1 - Stapenhorst, Carolin T1 - The concept as an operant instrument within the interdisciplinarity of the architectural design process N2 - In the introduction to their book "What is philosophy?" Gilles Deleuze and Felix Guattari deplore the inflationary and trivialised use of the term concept: "Finally, the most shameful moment came when computer science, marketing, design and advertising, all the disciplines of communication, seized hold of the word concept itself and said: 'This is our concern, we are the creative ones, we are the ideas men! We are the friends of the concept, we put in our computers.' " This doctoral thesis shares the concern of Gilles Deleuze and Felix Guattari, but still, it is a thesis in architecture and thus collocated within the field of the representatives of the "ideas men". It engages in architectural design theory, and refers in particular to the investigation of methodological approaches within the design process. Therefore, the thesis will not contribute to the philosophical dimension of the term, but intends to overcome its imprecise use within the architectural discourse, in compliance with Eugène Viollet-le-Duc's admonition relative to vague definitions: "Dans les arts, et dans l'architecture en particulier, les définitions vagues ont causé bien des erreurs, ont laissé germer bien des préjugés, enraciner bien des idées fausses. On met un mot en avant, chacun y attache un sens différent." The term concept in architecture is very often used as pure marketing collateral, it serves to sell an idea, a product, a design. Its functional applicability is reduced to a special manner of illustration, produced as one of the various design presentation documents at the end of the design process. In contrast, the original contribution of this thesis aims to give a precise, instrumental dimension to the term concept: the concept is the expression of a specific logic, capable to guide the decisional sequences of the process and thus to improve the quality of the designed projects. The motivation to define a specific instrumentality of the concept is closely connected to the issue of interdisciplinarity in the architects’ profession. The interdisciplinary character of the architectural field is widely accepted and discussed as such, but the thesis intends to give a more precise definition of the various kinds of competences involved by classifying them into either the internal or the external group. The traditional notion of interdisciplinarity, predominantly seen as collaboration between architects and technical experts, and, most notably, the historical, sometimes contentious, relationship between architects and engineers is described. Referring to recent developments, the transformation of the architect’s role within the professional sphere, marked by an increasing importance of diverse influences and linked to a growing risk of marginalisation, is illustrated. The thesis describes different ways to adapt to this specific kind of interdisciplinarity, which generally requires the architect’s ability to connect and to integrate various contents, different points of view and diverse scales. On the other hand, the big potential which is implicit in the interdisciplinary field is exposed: architects can inform their core competence, the design, by extracting contents of different disciplinary competences, pertaining or not pertaining to their own professional field. They have the possibility to cross fields of external competences in a selective way and by doing so they can build up a corpus of knowledge capable to generate and communicate guidelines and systematic methodologies for their design. At the end, the analysis of these two aspects allows the definition of a more specific professional profile of the architect as specialist of interdisciplinarity. The thesis is concerned with the theories around the design process. The design process is seen as open to inspection and critical evaluation, with major focus on the decisional sequences which characterise it. It concentrates on the process’ descriptiveness and the degree of self-conscious approaches applied within it. The importance of regulative, strategic mechanisms is illustrated by testimonies taken from a series of design researches and leads to the functional definition of the figure of the concept as representation of a coherent set of ideas, as generator of a project-specific system of rules and as communicator of decisional strategies. The concept's function is furthermore defined as communicative interface which generates and transmits the system of rules authoritative for all the disciplinary competences involved in the design process, a communicative interface which constitutes a basis of shared convictions capable to increase the efficiency of collaboration. Furthermore, the concept's capacity to explore and elaborate the contents of external disciplines is identified as a possible methodological approach to innovative design thinking. The approach to a specific functional definition of the concept is continued by the description of a series of instruments that are simultaneously generating and communicating it. It is outlined to which degree the concept itself is already the result of an ideational process, collocated within the initial phase of the design proceedings, serving as a guideline to them, but still continuously evolving and adapting in its progression. In addition, it is illustrated how all the diverse instruments of the concept are operational media through which the knowledge transition between different disciplines can occur. The considerations about the concept as operational instrument of design are elaborated with regard to a number of examples of didactical applications that are particularly involved in the development and teaching of specific design methods. These examples illustrate the interrelations between design theory and design education. They are derived from very different schools of architecture and diverse mindsets, but all of them transmit models of conceptual design thinking. KW - methodologies KW - instruments KW - interdisciplinarity KW - architectural design process KW - design theory Y1 - 2012 PB - Politecnico di Torino CY - Turin ER - TY - GEN A1 - Frauenrath, Tobias A1 - Fuchs, Katharina A1 - Hezel, Fabian A1 - Dieringer, Matthias A. A1 - Rieger, Jan A1 - Niendorf, Thoralf T1 - Improved cardiac triggering by combining multiple physiological signals: a cardiac MR feasibility study at 7.0 T T2 - 2012 ISMRM Annual Meeting Proceedings N2 - In current clinical cardiovascular MR (CMR) practice cardiac motion is commonly dealt with using ECG based synchronization. However, ECG is corrupted by magneto-hydrodynamic (MHD) effects in magnetic fields. This leads to artifacts in the ECG trace and evokes severe T-wave elevations, which might be misinterpreted as R-waves resulting in erroneous triggering. At (ultra)high field strengths, the propensity of ECG recordings to MHD effects is further pronounced. Pulse oximetry (POX) being inherently sensitive to blood oxygenation provides an alternative approach for cardiac gating. However, due to the travel time of the blood the peak of maximum oxygenation and hence the trigger is delayed by approx. 300 ms with respect to the ECG's R-wave. Also the peak of maximum oxygenation shows a jitter of up to 65 ms. Alternative triggering approaches include acoustic cardiac triggering (ACT). In current clinical practice cardiac gating / triggering commonly relies on using single physiological signals only. Realizing this limitation this study proposes a combined triggering approach which exploits multiple physiological signals including ECG, POX or ACT to track cardiac activity. The feasibility of the coupled approach is examined for LV function assessment at 7.0 T. For this purpose, breath-held 2D-CINE imaging in conjunction with cardiac synchronization was performed paralleled by real time logging of physiological waveforms to track (mis)synchronization between the cardiac cycle and data acquisition. Combinations of the ECG, POX and ACT signals were evaluated and processed in real time to facilitate reliable trigger information. Y1 - 2012 SN - 1545-4428 N1 - ISMRM 20th Annual Meeting & Exhibition, 5-11 May 2012, Melbourne, Australia ER - TY - GEN A1 - Gräßl, Andreas A1 - Renz, Wolfgang A1 - Hezel, Fabian A1 - Frauenrath, Tobias A1 - Pfeiffer, Harald A1 - Hoffmann, Werner A1 - Kellmann, Peter A1 - Martin, Conrad A1 - Niendorf, Thoralf T1 - Design, evaluation and application of a modular 32 channel transmit/receive surface coil array for cardiac MRI at 7T T2 - 2012 ISMRM Annual Meeting Proceedings N2 - Cardiac MR (CMR) at ultrahigh (≥7.0 T) fields is regarded as one of the most challenging MRI applications. At 7.0 T image quality is not always exclusively defined by signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). Detrimental effects bear the potential to spoil the signal-to-noise (SNR) and contrast-to-noise (CNR) benefits of cardiac MR (CMR) at 7.0 T. B₁⁺-inhomogeneities and signal voids represent the main challenges. Various pioneering coil concepts have been proposed to tackle these issues, enabling cardiac MRI at 7.0 T. This includes a trend towards an ever larger number of transmit and receive channels. This approach affords multi-dimensional B₁⁺ modulations to improve B₁⁺ shimming performance and to enhance RF efficiency. Also, parallel imaging benefits from a high number of receive channels enabling two-dimensional acceleration. Realizing the limitations of existing coil designs tailored for UHF CMR and recognizing the opportunities of a many element TX/RX channel architecture this work proposes a modular, two dimensional 32-channel transmit and receive array using loop elements and examines its efficacy for enhanced B¹+ homogeneity and improved parallel imaging performance. Y1 - 2012 SN - 1545-4428 N1 - ISMRM 20th Annual Meeting & Exhibition, 5-11 May 2012, Melbourne, Australia ER - TY - GEN A1 - Tkachenko, Valeriy A1 - von Knobelsdorff-Brenkenhoff, Florian A1 - Kleindienst, Denise A1 - Winter, Lukas A1 - Rieger, Jan A1 - Frauenrath, Tobias A1 - Dieringer, Matthias A. A1 - Santoro, Davide A1 - Niendorf, Thoralf A1 - Schulz-Menger, Jeanette T1 - Cardiovasular MR at 7Tesla: assessment of the right ventricle T2 - 2012 ISMRM Annual Meeting Proceedings N2 - The assessment of the right ventricle (RV) is a challenge in today's cardiology, but of growing clinical impact regarding patient prognosis in different cardiac diseases. The detection and differentiation of small wall motion abnormalities may help to enhance the differentiation of cardiomyopathies including Arrhythmogenic Rightventricular Cardiomyopathy. Cardiovascular magnetic resonance (CMR) at 1.5T is the accepted gold standard for RV quantification. The higher spatial resolution achievable at ultrahigh field strength (UHF) offers the potential to gain new insights into the structure and function of the RV. To approach this goal accurate RV chamber quantification at 7T has to be proven. Consequently this study examines the feasibility of assessment of RV dimensions and function at 7T using improved spatial resolution enabled by the intrinsic sensitivity gain of UHF CMR. For this purpose, a dedicated 16 channel TX/RX RF coil array is used together with 2D CINE fast gradient echo (FGRE) imaging. For comparison RV chamber quantification is conducted at 1.5T using a SSFP based state of the art clinical protocol. Y1 - 2012 SN - 1545-4428 N1 - ISMRM 20th Annual Meeting & Exhibition, 5-11 May 2012, Melbourne, Australia ER - TY - CHAP A1 - Moorkamp, Wilfried A1 - Peterson, Leif Arne A1 - Uibel, Thomas ED - Fouad, Nabil A. T1 - Nachhaltige Holzbrücken für Geh- und Radwege T2 - Bauphysik Kalender 2022: Holzbau, 22. Jahrgang N2 - Am Lehr- und Forschungsgebiet Holzbau der Fachhochschule Aachen wurden im Rahmen des Forschungsvorhabens „Nachhaltige Standardbrücken in Holzbauweise“ Standardtypen für Geh- und Radwegbrücken entwickelt. Die Brücken sind durch konsequente Umsetzungen von Maßnahmen des konstruktiven Holzschutzes für eine Nutzung von mehr als 80~Jahren konzipiert. Innovative Lösungen für Bauteile und Anschlüsse sowie Materialalternativen im Bereich des Belages und der Geländer ermöglichen eine wartungsarme Konstruktion und tragen somit zur Wirtschaftlichkeit und Nachhaltigkeit bei. Um den Einsatz der entwickelten Standardbrückentypen in der Praxis zu erleichtern, wurden Leistungsverzeichnisse, Musterstatiken, Musterzeichnungen und umfangreiche Detailkataloge als Unterstützung für Planer und Bauherren erstellt. Damit die Randbedingungen für eine lange Lebensdauer während der Nutzung der Brücke erhalten bleiben, wurden Leitfäden für die Pflege und Wartung sowie für die Brückenprüfung erarbeitet. Der Beitrag gibt Einblicke in das Forschungsvorhaben und seine Resultate. Y1 - 2022 SN - 9783433033609 (Print) SN - 9783433611081 (Online) U6 - https://doi.org/10.1002/9783433611081.ch17 SP - 574 EP - 592 PB - Ernst & Sohn CY - Berlin ER - TY - CHAP A1 - Moorkamp, Wilfried A1 - Peterson, Leif Arne A1 - Uibel, Thomas ED - Wehren, Cedric T1 - Standardholzbrücken für kommunale Geh- und Radwege T2 - Strukturen, Formen und Prinzipien : Festschrift zum 60. Geburtstag von Univ.-Prof. Dr.-Ing. Martin Trautz Y1 - 2023 SN - 978-3-95886-500-6 SP - 140 EP - 165 PB - RWTH Aachen CY - Aachen ER - TY - CHAP A1 - Bedbur, Christian A1 - Moorkamp, Wilfried A1 - Peterson, Leif Arne A1 - Uibel, Thomas ED - Kuhlmann, Ulrike T1 - Holzbrücken mit Natursteinbelägen - Untersuchungen zur Aktivierung der Verbundwirkung T2 - Doktorandenkolloquium Holzbau Forschung + Praxis 2020 Y1 - 2020 N1 - 8. Doktorandenkolloquium „Holzbau Forschung + Praxis“, 05. und 06. März 2020, Stuttgart SP - 53 EP - 60 PB - Universität Stuttgart, Institut für Konstruktion und Entwurf CY - Stuttgart ER -