Fakultät 5 Verkehrs- und Maschinensysteme

809 Items

Recent Submissions
What is the “Source” of Open Source Hardware?

Bonvoisin, Jérémy ; Mies, Robert ; Boujut, Jean-François ; Stark, Rainer (2017)

What “open source” means once applied to tangible products has been so far mostly addressed through the light of licensing. While this approach is suitable for software, it appears to be over-simplistic for complex hardware products. Whether such a product can be labelled as open source is not only a question of licence but a question of documentation, i.e. what is the information that sufficie...

Stochastisches Verfahren zur Simulation von Breitbandschall in Triebwerkfans

Wohlbrandt, Attila (2017)

Die vorliegende Arbeit beschäftigt sich mit der Anwendung des Random-Particle-Mesh-Verfahrens (RPM) zur Simulation von Fanbreitbandschall. Aus zeitgemittelten, turbulenten Größen erzeugt das Verfahren zeitabhängige Fluktuationen, die zur Vorhersage der Schallentstehung hinreichend sind. Es wird isotrope, freie Turbulenz in Form von divergenzfreien Geschwindigkeitsfluktuationen synthetisiert. D...

Flashback prevention in lean-premixed hydrogen combustion

Reichel, Thoralf G. (2017)

The focus of this study is the combustion of hydrogen in air as it relates to typical gas turbine engines. Hydrogen–air combustion occurs in the absence of any carbon-based emissions and the only combustion products are water vapor and oxides of nitrogen (NOx). However, due to the very low flammability limit of hydrogen, it can be burned at much lower equivalence ratios than typical hydrocarbon...

Gefäßsteifigkeitsmessung als Screening-Verfahren zur verbesserten Beurteilung des kardiovaskulären Risikos

Karczewski, Tina (2017)

In 2003 the ESH/ESC recommended the arterial stiffness measurement for arterial hypertension management in their guidelines for the first time. In addition to the conventional blood pressure measurement, the clinicians are advised to measure following parameters: pulse wave velocity (PWV), augmentation pressure (AugP) and central blood pressure (zBD). A change in shape of the blood pressure wav...

Coupling of continuum mechanics and electrodynamics

Reich, Felix Alexander (2017)

In the literature, many models of electromagnetic momentum are proposed. Each model implies a form of the electromagnetic force density, which acts as a source in the mechanical momentum balance. The debate as to which model of the electromagnetic force is "correct" for arbitrary materials and processes is ongoing. Most authors argue in favor or against specific models by virtue of thought expe...

Standardised documentation of instrument use during laparoscopic surgery

Zickerow, Matthias ; Holmer, Christoph ; Kraft, Marc (2013)

To date, usability problems for laparoscopic instruments have mainly been investigated using questionnaires or laboratory studies. However, this methodology prevents the duration and frequency of instrument use from being documented objectively. Therefore, a tablet was used to create a graphic user interface which enables instrument use by operating and assisting surgeons to be documented with ...

A mobile gait analysis system for optimization of prosthetic alignments

Westebbe, Bettina ; Thiele, Julius ; Kraft, Marc (2013)

The prosthesis alignment is of central importance for a harmonic gait, especially for upper limb amputees. Today alignment optimization is based on static measuring and the experience of the orthopaedic technician. To objectify the alignment process a mobile gait analysis system based on 10 inertial sensors and a 6 DOF force and moment sensor was developed at the TU Berlin. The dedicated softwa...

Ergonomic problems originating in the use of high-frequency and ultrasonic medical devices

von Saucken, Anna-Maria ; Donner, Sylvia ; Kraft, Marc (2012)

High-frequency and ultrasonic medical devices are widely used in laparoscopic surgical procedures. Using these devices can result in ergonomic problems. Two studies were performed: in a questionnaire surgeons were asked to evaluate laparoscopic surgical instruments. Based on the resulting 74 data sets it was possible to define various improvements to the design of instruments. In a subsequent f...

Technically assisted rehabilitation

Stieglitz, Thomas ; Niemann, Hildegard ; Kraft, Marc (2012)

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Diffusionsphänomene beim Löten mit Nickelbasisloten

Stahn, Oliver (2017)

Beim Hochtemperaturlöten mit Nickelbasisloten besteht seit langem das Problem der Bildung spröder Phasen in der Lötnaht. Dieses wurde bisher nur in wenigen Einzelfällen gelöst. Ziel dieser Arbeit ist es die Prozessführung während des Lötens so zu wählen, dass sich keine spröden Phasen bilden können. Dies resultiert in einer signifikanten Steigerung der Verbindungsqualität und der Gebrauchseigen...

Benefits and obstacles of sustainable product development methods

Stark, Rainer ; Buchert, Tom ; Neugebauer, Sabrina ; Bonvoisin, Jérémy ; Finkbeiner, Matthias (2017)

In the last few years, numerous approaches have been introduced for supporting design engineers in developing more sustainable products. However, so far, these efforts have not led to the establishment of a commonly acknowledged standard methodology for Sustainable Product Development (SPD). This brings into question the relevance of developing new methods and calls for more efforts in testing ...

Aktive Beeinflussung von Querströmungsinstabilitäten mit pneumatischen Aktuatoren

Lohse, Jakob (2017)

Die Vorliegende Arbeit behandelt die Kontrolle von Querströmungsinstabilitäten mit pneumatischen Aktuatoren. Über stationäres Ausblasen oder Einsaugen durch spannweitig periodisch angeordnete Lochreihen wird ein künstlich angeregtes Wirbelsystem in die dreidimensionale Grenzschicht eingebracht, welches das Wachstum der natürlichen Querströmungswirbel dämpft und somit die Transition stromab vers...

Vergleichende Beschreibung im Verkehr am Beispiel des differenzierten Stadtschnellbahnverkehrs in Ballungsräumen

Blome, Christian (2017)

Der Öffentliche Personennahverkehr unterliegt zeitlich schwankender Nachfrage. In Zeiten erhöhter Nachfrage wird zur Befriedigung der Verkehrsbedürfnisse das Angebot ausgeweitet. Übliche Mittel dazu sind einerseits der Einsatz von Formationen mit größerer Kapazität, soweit dies systemtechnisch möglich ist, und andererseits eine Verdichtung des Fahrtenangebotes. Diese klassischen Verdichtungspri...

Analysing the impacts of various environmental parameters on the biodiversity status of major habitats

Winter, Lisa ; Berger, Markus ; Minkov, Nikolay ; Finkbeiner, Matthias (2017)

Anthropogenic impacts on the environment often result in loss of biodiversity. However, the effects of different parameters (such as soil pH) on biodiversity, which can be influenced by human activities, are poorly investigated on a global scale. The paper at hand proposes an approach to examine the relationship between biodiversity and several parameters, which can be anthropogenically influen...

Comparative study of two dynamics-model-based estimation algorithms for distributed drive electric vehicles

Zhang, Xudong ; Göhlich, Dietmar ; Fu, Chenrui (2017)

The effect of vehicle active safety systems is subject to the accurate knowledge of vehicle states. Therefore, it is of great importance to develop a precise and robust estimation approach so as to deal with nonlinear vehicle dynamics systems. In this paper, a planar vehicle model with a simplified tire model is established first. Two advanced model-based estimation algorithms, an unscented Kal...

Dynamical modelling of hydraulic excavator considered as a multibody system

Mitrev, Rosen ; Janošević, Dragoslav ; Marinković, Dragan (2017)

This paper considers the development of a plane multibody mechanical model of a hydraulic excavator simultaneously containing an open kinematic chain and closed loops. The Lagrange multiplier technique is used for modelling of the constrained mechanical systems. This approach is used for working out the dynamic equations of excavator motion in the case of performing transportation and digging o...

Beschreibung des Reaktionsablaufs energetischer Materialien bei Laserbestrahlung

Lück, Martin (2017)

Die Untersuchung der Wirkung intensiver Laserstrahlung auf energetische Materialien ist ein Thema mit großer Relevanz für die Sicherheitsforschung und findet Anwendung bei der Entwicklung neuartiger Verfahren zur sicheren Entschärfung von Sprengsätzen. Die dabei auftretenden Prozesse konnten in der Vergangenheit noch nicht adäquat beschrieben werden und sind Gegenstand der vorliegenden Arbeit. ...

Prospektiv-Nutzergerechte Softwaregestaltung in integrierten OP-Sälen

Saucken, Anna-Maria von (2017)

Die Vielfalt medizinischer Geräte und Software im OP-Saal zur Ausführung minimal invasiver Interventionen nimmt, besonders in Hinblick auf die intraoperative Einbindung bildgebender Verfahren, stetig zu. Dabei verfügt nahezu jedes einzelne Gerät über ein eigenes Bedienkonzept. Selbst integrierte OP-Säle, die ein Touch Panel einer zusammengeführten Steuerung aller medizinischen Geräte ber...

Recursive dynamic mode decomposition of transient and post-transient wake flows

Noack, Bernd R. ; Stankiewicz, Witold ; Morzyński, Marek ; Schmid, Peter J. (2016)

A novel data-driven modal decomposition of fluid flow is proposed, comprising key features of proper orthogonal decomposition (POD) and dynamic mode decomposition (DMD). The first mode is the normalized real or imaginary part of the DMD mode that minimizes the time-averaged residual. The Nth mode is defined recursively in an analogous manner based on the residual of an expansion using the first...

Weakly nonlinear analysis of thermoacoustic instabilities in annular combustors

Ghirardo, G. ; Juniper, M. P. ; Moeck, Jonas P. (2016)

Rotationally symmetric annular combustors are of practical importance because they generically resemble combustion chambers in gas turbines, in which thermoacoustically driven oscillations are a major concern. We focus on azimuthal thermoacoustic oscillations and model the fluctuating heat release rate as being dependent only on the local pressure in the combustion chamber. We study the dynamic...