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Magnetic confinement fusion relies on plasma heating and plasma control using gyrotron oscillators providing at megawatt power levels. The operational reliability decreases when operating at the performance limits due to increasing parasitic mode activity. This work demonstrates for the first time the automated, fast recovery of nominal gyrotron operation during a pulse by exploiting the hysteretic gyrotron behaviour after a mode switch being in use at the Wendelstein 7-X ECRH facility.
Umfang: XVII, 237 S.
Preis: 47.00 €
Buchdetails
This work proposes a novel method for a matching tool between MRI and spot mammograms. Two registration methods are used : a biomechanical model based registration between MRI and full X-ray mammograms, followed by an image based registration between full and spot mammograms. The proposed methods have been tested using 51 patients from the Medical University of Vienna. For the analyzed dataset, the proposed methods showed not only promising results but also the feasibility of clinical use.
Umfang: XIV, 238 S.
Preis: 53.00 €
Buchdetails
In dieser Arbeit werden Ansätze zur verbesserten Signalanalyse mehrstimmiger Musikaufnahmen vorgestellt, die auf künstlichen neuronalen Netzen basieren. Diese Ansätze ermöglichen eine objektive Bewertung der Aufnahmequalität von Amateuraufnahmen, eine verbesserte zeitabhängige Detektion aktiver Musikinstrumente sowie eine bessere Separation von Ensemble-Aufnahmen mit unterschiedlichen Instrumenten.
In this work, improved signal analysis approaches for polyphonic music recordings, based on artificial neural networks, are presented. These approaches enable an objective estimation of the recording quality of amateur recordings, an improved time-dependent detection of active musical instruments, and an improved separation of ensemble recordings with different instruments.
Umfang: X, 184 S.
Preis: 39.00 €
Buchdetails
High energy demand is one reason for high costs of carbon fibers. One option to decrease them is to use microwave heating instead of conventional heating. In this work, steps towards a microwave assisted process during the stabilization phase are presented. In-situ dielectric measurements are performed and a reaction kinetics model is setup in connection to the dielectric loss. This allows to calculate a stabilization degree and fiber temperatures leading to a basic process understanding.
Umfang: XVII, 142 S.
Preis: 42.00 €
Buchdetails
Diese Arbeit präsentiert ein physikalisch motiviertes Modell, welches die Zellspannung einer Lithium-Ionen-Batterie auf Basis der Zellimpedanz vorhersagt. Das Modell wurde an einer kommerziellen Pouchzelle parametriert und validiert. In einer umfassenden Simulationsstudie wird der Einfluss der Elektrodenmikrostruktur auf die Energie- und Leistungsdichte der Zelle quantifiziert. Darüber hinaus wird eine Routine zur Entwicklung anwendungsspezifischer Zelldesigns vorgestellt.
This work presents a physically motivated model that predicts the cell voltage of a lithium-ion-battery based on its impedance. The model was parameterized and validated on a commercial pouch cell. In a comprehensive simulation study, the influence of the electrode microstructure parameters on the energy and power density is quantified. Furthermore, a routine for the development of application-specific cell designs is developed.
Umfang: V, 248 S.
Preis: 49.00 €
Buchdetails
High-speed electro-optic modulators in silicon platform are introduced and experimentally verified. The devices rely on plasmonic and photonic slot waveguides and are combined with efficient organic electro-optic materials. The bandwidth limitation of conventional silicon-organic-hybrid modulators is circumvented by capacitive coupling of the microwave signal. An advanced terahertz link that upconverts data directly from a 360 GHz carrier to an optical carrier is demonstrated for the first time.
Umfang: XII, 170 S.
Preis: 42.00 €
Buchdetails
Deep learning is widely applied to sparse 3D data to perform challenging tasks, e.g., 3D object detection and semantic segmentation. However, the high performance of deep learning comes with high costs, including computational costs and the effort to capture and label data. This work investigates and improves the efficiency of deep learning for sparse 3D data to overcome the obstacles to the further development of this technology.
Umfang: XIII, 227 S.
Preis: 45.00 €
Buchdetails
SOH (silicon-organic hybrid) elektrooptische Modulatoren kombinieren Siliziumphotonik mit organischen elektro-optischen Materialien. Dieses Buch befasst sich mit Aspekten, die speziell für den Einsatz von SOH-Modulatoren in praktischen optischen Hochgeschwindigkeitskommunikationssystemen relevant sind, wie z. B. Aufbau- und Verbindungstechnik, Modellierung und die Implementierung effizienter Modulationsformate für IM/DD-Formate.
Silicon-organic hybrid (SOH) electro-optic modulators combining silicon photonic structures with organic EO materials are investigated. This book addresses aspects that are specifically relevant for the use of SOH modulators in practical high-speed optical communication systems such as packaging, modelling of the device, and the implementation of efficient intensity-modulation/direct-detection (IM/DD) modulation formats.
Umfang: XIII, 173 S.
Preis: 41.00 €
Buchdetails
The increasing use of automated laser welding processes causes high demands on process monitoring. This work demonstrates methods that use a camera mounted on the focussing optics to perform pre-, in-, and post-process monitoring of welding processes. The implementation uses machine learning methods. All algorithms consider the integration into industrial processes. These challenges include a small database, limited industrial manufacturing inference hardware, and user acceptance.
Umfang: XVI, 226 S.
Preis: 46.00 €
Buchdetails
Der Quasi-n-Level Betrieb des Flying Capacitor Umrichters (FlCs) ist eine optimierte Betriebsweise eines Multilevel-Umrichters. Der Quasi-n-Level Betrieb eines Multilevel-Umrichters wurde mit einer Analyse der Vor- und Nachteile vorgestellt. Für den Q2LB des FlCs wird die Theorie sowie die Regelung, die Modulation und die Symmetrierungsalgorithmen vorgestellt. Zur Validierung der Theorie wurde ein Mittelspannungsprototyp aufgebaut.
The quasi-n-level operation of the flying capacitor converter (FCCs) is an optimized operation mode of a multilevel converter. The quasi-n-level operation of a multilevel converter was presented with an analysis of its advantages and disadvantages. For the Q2LB of the FCC, the theory as well as the control, modulation and balancing algorithms are presented. A medium voltage prototype was built to validate the theory.
Umfang: VIII, 237 S.
Preis: 45.00 €
Buchdetails
