Technische Universität Berlin

6575 Items

Recent Submissions
Modern methods for investigating the stability of a pitching floating platform wind turbine

Lennie, Matthew ; Marten, David ; Pechlivanoglou, George ; Nayeri, Christian Navid ; Paschereit, Christian Oliver (2017)

The QBlade implementation of the lifting-line free vortex wake (LLFVW) method was tested in conditions analogous to floating platform motion. Comparisons against two independent test cases using a variety of simulation methods show good agreement in thrust forces, rotor power, blade forces and rotor plane induction. Along with the many verifications already undertaken in the literature, it seem...

Application of the enzyme controlled glucose feeding for the production of recombinant proteins

Abdou Ali, Basant (2018)

One of the prime objectives of any bioprocess development is to enhance the microbial growth and product yields. Correspondingly, for recombinant proteins it is the aim increase the yields of the soluble, active and correctly folded molecule. There are many factors that could influence the product yield like medium optimization and the performance of the bioprocess itself. The aim of this study...

Physical minimal models of amoeboid cell motility

Kulawiak, Dirk Alexander (2017)

Cell locomotion plays an important role in many biological processes such as the immune system, embryonic development, or cancer metastasis. In these examples, cells interact with their environments or coordinate their movements with other cells, creating collective behavior. In this thesis, we utilize minimal modeling to investigate single and collective cell motility in three different settin...

Theoretical and experimental investigations of creep groan in automotive disk brakes

Xingwei, Zhao (2018)

Due to the increasing comfort claims of customers, the study on low frequency creep groan has been receiving increasing attention currently. This thesis forces on the study of the fundamental mechanism of creep groan theoretically and experimentally. In order to understand creep groan step by step, the design of test rigs concentrating on creep groan are presented. A test rig with an idealized...

Micro-scale variability of air temperature within a local climate zone in Berlin, Germany, during summer

Quanz, Justus A. ; Ulrich, Susanne ; Fenner, Daniel ; Holtmann, Achim ; Eimermacher, Jonas (2018)

The urban climate, especially the near-surface air temperature ( T ), is influenced to large amounts by urban surface properties on the local-scale. Landscape classification schemes, like the Local Climate Zone (LCZ) concept, classify neighbourhoods on this scale based on their surface properties, neglecting sub-scale heterogeneity in the urban structure and its potential effects on T . To quan...

Comparative venomics of the Vipera ammodytes transcaucasiana and Vipera ammodytes montandoni from Turkey provides insights into kinship

Hempel, Benjamin-Florian ; Damm, Maik ; Göçmen, Bayram ; Karis, Mert ; Oguz, Mehmet Anıl ; Nalbantsoy, Ayse ; Süssmuth, Roderich D. (2018)

The Nose-horned Viper (Vipera ammodytes) is one of the most widespread and venomous snakes in Europe, which causes high frequent snakebite accidents. The first comprehensive venom characterization of the regional endemic Transcaucasian Nose-horned Viper (Vipera ammodytes transcaucasiana) and the Transdanubian Sand Viper (Vipera ammodytes montandoni) is reported employing a combination of intact...

Design parameters of vortex pumps

Gerlach, Angela ; Thamsen, Paul Uwe ; Wulff, Sebastian ; Brix Jacobsen, Christian (2017)

Vortex pumps can impel solid-containing fluids and are therefore widely applied, from wastewater transport to the food industry. Despite constant efforts to improve vortex pumps, however, they have remained relatively inefficient compared to conventional centrifugal pumps. To find an optimized design of vortex pumps, this paper provides a systematic analysis on experimental studies that investi...

Accessing the dark exciton spin in deterministic quantum-dot microlenses

Heindel, Tobias ; Thoma, Alexander ; Schwartz, Ido ; Schmidgall, Emma R. ; Gantz, Liron ; Cogan, Dan ; Strauß, Max ; Schnauber, Peter ; Gschrey, Manuel ; Schulze, Jan-Hindrik ; Strittmatter, Andre ; Rodt, Sven ; Gershoni, David ; Reitzenstein, Stephan (2017)

The dark exciton state in semiconductor quantum dots (QDs) constitutes a long-lived solid-state qubit which has the potential to play an important role in implementations of solid-state-based quantum information architectures. In this work, we exploit deterministically fabricated QD microlenses which promise enhanced photon extraction, to optically prepare and read out the dark exciton spin and...

Physics of prestall propagating disturbances in axial compressors and their potential as a stall warning indicator

Eck, Mario ; Geist, Silvio ; Peitsch, Dieter (2017)

Axial compressors in aero engines are prone to suffering a breakdown of orderly flow when operating at the peak of the pressure rise characteristic. The damaging potential of separated flows is why a safe distance has to be left between every possible operating point and an operating point at which stall occurs. During earlier investigations of stall inception mechanisms, a new type of prestall...

Four wave mixing at 1550 nm in silicon waveguides

Gajda, Andrzej (2017)

Traffic in data communication networks has seen continuous growth over many decades. Taking the example of transport networks we observe a growth rate of about 60% per year in capacity. The increase in traffic is supported by various technologies but mainly driven by applications related to social media, moving images, internet of things etc. An important contender for future increase of fiber ...

IR spectro-electrochemistry of an adsorbed oxygen-tolerant [NiFe] hydrogenase on conductive surfaces

Heidary, Nina (2017)

Hydrogenases are metalloenzymes, catalyzing the reversible oxidation of molecular hydrogen into two protons and two electrons. The 'Knallgasbacterium' Ralstonia eutropha H16 (Re) is one of the few examples, harboring several [NiFe] hydrogenases that established mechanisms to enable catalytic conversion of H2 in the presence of O2. In order to exploit the catalytic potential of these oxygen-tole...

Organisatorisch-technisches Konzept für eine Forschungsdaten-Infrastruktur in der TU Berlin

Kuberek, Monika (2012-03-15)

Das vorliegende organisatorisch-technische Konzept hat zum Ziel, an der TU Berlin eine Forschungsdaten-Infrastruktur aufzubauen, die die langfristige Sicherung und Verfügbarkeit der hier entstandenen Forschungsdaten und der darauf basierenden Forschungspublikationen gewährleistet. Um die Forschungsdaten-Infrastruktur organisatorisch in der TU Berlin zu verankern und die Nachhaltigkeit der getro...

Micro-electromechanical affinity sensor for the monitoring of glucose in bioprocess media

Theuer, Lorenz ; Lehmann, Micha ; Junne, Stefan ; Neubauer, Peter ; Birkholz, Mario (2017)

An affinity-viscometry-based micro-sensor probe for continuous glucose monitoring was investigated with respect to its suitability for bioprocesses. The sensor operates with glucose and dextran competing as binding partner for concanavalin A, while the viscosity of the assay scales with glucose concentration. Changes in viscosity are determined with a micro-electromechanical system (MEMS) in th...

Real-time robustness evaluation of regression based myoelectric control against arm position change and donning/doffing

Hwang, Han-Jeong ; Hahne, Janne Mathias ; Müller, Klaus-Robert (2017)

There are some practical factors, such as arm position change and donning/doffing, which prevent robust myoelectric control. The objective of this study is to precisely characterize the impacts of the two representative factors on myoelectric controllability in practical control situations, thereby providing useful references that can be potentially used to find better solutions for clinically ...

Learning from label proportions in brain-computer interfaces

Hübner, David ; Verhoeven, Thibault ; Schmid, Konstantin ; Müller, Klaus-Robert ; Tangermann, Michael ; Kindermans, Pieter-Jan (2017)

Objective Using traditional approaches, a brain-computer interface (BCI) requires the collection of calibration data for new subjects prior to online use. Calibration time can be reduced or eliminated e.g., by subject-to-subject transfer of a pre-trained classifier or unsupervised adaptive classification methods which learn from scratch and adapt over time. While such heuristics work well in p...

P1-Nonconforming finite elements on triangulations into triangles and quadrilaterals

Altmann, Robert ; Carstensen, C. (2012)

The P1-nonconforming finite element is introduced for arbitrary triangulations into quadrilaterals and triangles of multiple connected Lipschitz domains. An explicit a priori analysis for the combination of the Park–Sheen and the Crouzeix–Raviart nonconforming finite element methods is given for second-order elliptic PDEs with inhomogeneous Dirichlet boundary conditions.

Quantum light driven many level systems in the weak and strong coupling limits

Chatraee Azizabadi, Shahabedin (2017)

We propose a possibility to study the quantum light excitation of atomic systems. To confine our study, we limit the configuration to two and four level emitters as target systems. Source and target are coupled via unidirectional waveguide. We numerically implement the cascaded formalism and use the source-target approach. Herein, we focus on continuous excitation scenarios where the source s...

Ultrafast dynamics of nanoparticles in highly intense X-Ray pulses

Bucher, Maximilian Jakob (2017)

With the advent of X-ray free electron laser, such as the Linac Coherent Light Source (LCLS), structural studies on non-repetitive and non-reproducible nanoparticles, such as single bio-molecules appear imminent. A key challenge to increasing the resolution of single particle imaging is radiation damage. Only a sound understanding of the underlying damage processes, such as the nanoplasma expan...

A cloud recycling light

Werner, Liss C. (2017-09)

The paper focuses on the question ``How does our built environment, urban culture and architectural production change through humans feeding back into digital systems of pre-fabrication and systems fostering industry 4.0?'' It discusses some risks and possibilities of digitisation and the city in an era of sustainability, networked design methods, production processes and digital communica...

Beiträge zur bioinspirierten Katalyse

Lindenmaier, Nils (2017)

In dieser Arbeit wurden einkernige Ni- und heterodimere [NiFe]-Komplexe im Kontext der von [NiFe]-H2ase und -CODH „bioinspirierten” Katalyse synthetisiert und untersucht. Im ersten Teil der Arbeit wurde ein neuartiger Silylen-Pyridin-Hybridligand für die Koordination von Nickel(II)- und Nickel(0)-Spezies entwickelt und auf seine σ-Donor- und π-Akzeptoreigenschaften hin analysiert. Der zweite Te...