Fakultätskolloquium der Technischen Fakultät im WS 2015/16
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Die Kolloquien an den Instituten für Elektrotechnik und Informationstechnik sowie Materialwissenschaften:
Jeweils montags eine halbe Stunde vor Beginn der Vorträge, also um 16.45 Uhr, werden
die Gastredner den Besuchern des Kolloquiums in einer zwanglosen
Runde bei einer Tasse Kaffee in der "Eisdiele" (Eingangshalle Geb. D,
neben dem "Aquarium") vorgestellt.
Ansprechpartnerin: Tanja Wengler (Tel. 0431-880-6001) dekanat@tf.uni-kiel.de
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Die Kolloquien am Institut für Informatik:
Alle Vorträge finden -
soweit nicht anders angegeben - im Raum Ü2/K des Instituts für
Informatik (Ludewig-Meyn-Str. 2, Vorbau des Mathematischen Seminars) freitags um 14 Uhr c.t. statt. 45 Minuten vor Vortragsbeginn stehen Tee
und Kaffee bereit.
Ansprechpartner/innen: Geschäftszimmer des Instituts für Informatik (Tel. 0431 880-4465)aktuell@informatik.uni-kiel.de
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Wenn Sie die Einladungen per E-Mail erhalten möchten tragen Sie sich bitte in die Mailingliste ein.
Nachfolgend alle Vortragstermine in chronologischer Abfolge
Kolloquiumsvortrag: Prof. Joachim Holtz, Life IEEE Fellow, University of Wuppertal / 19.10.15
19.10.2015 von 17:15 bis 18:45
Institut Elektrotechnik und Informationstechnik, Kaiserstr. 2, 24143 Kiel, Geb. D Raum: "Aquarium""
Titel: Reducing IGBT Switching Losses by Gate Charge Control
Abstract:
IGBTs are voltage controlled switching devices. Their fast switching characteristics
generate high voltage gradients which stress the motor winding insulation and generate
undesired bearing currents in ac drive systems. Electromagnetic interference may happen
with other electronic apparatus. Also the current gradients are high. They increase the diode
turn-off losses by generating high reverse recovery currents.
Voltage gradients are conventionally reduced by feeding the gate control signals through
resistors. The IGBT gate capacitance then delays the gate voltage changes, and thus increases
the transition intervals between switching states at the expense of higher switching losses.
The existing drawbacks are overcome by controlling the gate charge gradients at turn-on and
turn-off, thereby enforcing predetermined values of dv/dt and di/dt. Nonlinear dynamic IGBT
properties are accounted for. The gate charge profiles versus time are made dependent on the
particular load current value at switching, and on the internal device capacitances. These
incur rapid changes during the switching process under the influence of the device voltage
waveforms. Experiment results using 6.6 kV / 400 Amp IBGTs show that dv/dt is reduced
from 4 kV to 1 kV/ms while switching losses reduce to 70%.
About the Speaker
Joachim Holtz graduated in 1967 and received the Ph.D. degree in 1969 from the Technical
University Braunschweig, Germany.
In 1969 he became Associate Professor and, in 1971, Full Professor and Head of the Control
Engineering Laboratory, Indian Institute of Technology in Madras, India. He joined the
Siemens Research Laboratories in Erlangen, Germany, in 1972. From 1976 to 1998, he was
Professor and Head of the Electrical Machines and Drives Laboratory, Wuppertal University,
Germany. He is presently Professor Emeritus and a Consultant.
Dr. Holtz has extensively published, among others 12 invited papers in journals. He has
earned 15 Prize Paper Awards. He is the coauthor of seven books, and holds 33 patents.
Dr. Holtz is the recipient of the IEEE Industrial Electronics Society Dr. Eugene Mittelmann
Achievement Award, the IEEE Industrial Applications Society Outstanding Achievement
Award, the IEEE Power Electronics Society William E. Newell Field Award, the IEEE Third
Millennium Medal, the Anthony J. Hornfeck Service Award, and the IEEE Lamme Gold
Medal. He is a Life Fellow of the IEEE.
Dr. Holtz is Past Editor-in-Chief of the IEEE Transactions on Industrial Electronics, Distinguished
Lecturer of the IEEE Industrial Applications Society and IEEE Industrial Electronics
Society.
Prof. Liserre
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Kolloquiumsvortrag: Dr. Ronald Kriemann, Max-Planck-Institut f. Mathem. i. d. Naturwissensch., Leipzig / 22.10.15
22.10.2015 von 13:30 bis 16:00
Institut für Informatik, Christian-Albrechts-Platz 4, 24118 Kiel, Hochhaus, Raum 1304a
Titel: H-Arithmetic for Many-Core Systems
Abstract:
Classical arithmetic for hierarchical matrices, e.g. matrix multiplication or LU factorization, is based on recursive algorithms on local matrix blocks. Due to the local scope, this formulation may introduce additional dependencies between the actual computational tasks. This significantly limits the parallel speedup of the arithmetic on modern many-core systems. An alternative formulation of the arithmetic is described, which overcomes these limitations by explicitly defining computational tasks and their dependencies on a global scope. Furthermore, tasks and dependencies form a directed acyclic graph, which can be used for scheduling tasks onto processors. Numerical examples will demonstrate the effectiveness of this new approach.
Prof. Börm
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Kolloquiumsvortrag: NN / 26.10.15
26.10.2015 von 17:15 bis 18:45
Institut Ostufer, Kaiserstr. 2, 24143 Kiel, Geb. D Raum: "Aquarium"
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Kolloquiumsvortrag: Prof. Dr. José Claudio Verschae, Pontifica Universidad Católica de Chile / 30.10.15
30.10.2015 von 14:15 bis 15:45
Institut für Informatik, Ludewig-Meyn-Str. 2, Übungsraum 2
Titel: Online Machine Covering: Exploiting Symmetries to Control Migration
Abstract:
Load balancing in parallel machines is a fundamental problem that has been studied extensively in the literature. We consider a version where jobs are revealed online one by one. Our aim is to assign the jobs to a given number of machines in order to balance the load, more specifically, to maximize the load of the least loaded machine. In the classic online model decisions are irrevocable, which is unrealistic for several applications.
We consider a relaxed version proposed by Sanders et al., where a limited amount of jobs can be reassigned at the arrival of a new job. We are interested in understanding the trade-off between the quality of solutions and the amount of migrated jobs. In this talk I will introduce the problem and basic techniques. Then I will focus on the analysis of a simple greedy algorithm. Our main observation is that well chosen small perturbations of the processing times creates several types of symmetries in the solutions. This implies that solutions that are a priori very different are actually equivalent modulo these symmetries. We show how this property can be exploited algorithmically in order to find good solutions that are similar after the arrival of new jobs, thus yielding improved algorithms for this problem.
This is joint work with Waldo Galvez and Jose Soto.
Prof. Jansen
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Kolloquiumsvortrag: NN / 02.11.15
02.11.2015 von 17:15 bis 18:45
Institut Ostufer, Kaiserstr. 2, Geb. D Raum: "Aquarium
Titel: folgt
Abstract: folgt
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Kolloquiumsvortrag: N.N. / 06.11.15
06.11.2015 von 14:15 bis 15:45
Institut für Informatik, Ludewig-Meyn-Str. 2, Übungsraum 2
Titel: folgt
Abstract: folgt
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Kolloquiumsvortrag N. N., 09.11.2015
09.11.2015 von 17:15 bis 18:45
Institut Ostufer, Kaiserstr. 2, Geb. D Raum: "Aquarium
Titel:
Abstract:
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Kolloquiumsvortrag: N.N. / 13.11.15
13.11.2015 von 14:15 bis 15:45
Institut für Informatik, Ludewig-Meyn-Str. 2, Übungsraum 2
Titel: folgt
Abstract: folgt
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Kolloquiumsvortrag: NN / 16.11.15
16.11.2015 von 17:15 bis 18:45
Institut Ostufer, Kaiserstr. 2, Geb. D Raum: "Aquarium
Titel: folgt
Abstract: folgt
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Kolloquiumsvortrag: N.N. / 20.11.15
20.11.2015 von 14:15 bis 15:45
Institut für Informatik, Ludewig-Meyn-Str. 2, Übungsraum 2
Titel: folgt
Abstract: folgt
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Kolloquiumsvortrag: Dr. Sanjeev Kumar Srivastava, Indian Institute of Technology, Kharagpur, India / 23.11.15
23.11.2015 von 17:15 bis 18:45
Institut für Materialwissenschaften, Kaiserstr. 2, 24143 Kiel, Geb. D, Raum: "Aquarium
Titel: Microscopic and macroscopic studies of electron correlations in solids
Abstract:
Electron correlations determine or influence almost all aspects of solid
state properties, be it electrical transport, magnetic and superconducting
properties, or even more complex strong electron correlation based phenomena.
The study of electron correlations, thus, occupies a key position in the
central theme of current experimental and theoretical research in condensed
matter physics. There are two basic ways to investigate electron correlations:
(i) studies of macroscopic properties, which basically constitute a report on
the ensemble- and time-averaged behaviour of the solid, and (ii) microscopic
investigations, which essentially provide an explanation to the macroscopic
behaviour. The microscopic measurements are performed at very short length (~ 1
- 10 nm) and time (fs - ns) scales. An extremely useful
microscopic technique is the observation of perturbation, produced by the
interactions between the crystal electromagnetic fields and nuclear
electromagnetic moments, of the angular anisotropic distribution of the
intensity of γ-rays emitted by a radioactive nucleus produced in a heavy ion induced
fusion evaporation reaction and subsequently implanted into the solid. The
technique is known as Time-Differential Perturbed Angular Distribution (TDPAD).
It is further desirable always to compliment the experimental results with
first-principles density functional theory (DFT).
This talk will begin with short descriptions of the basic principles of the microscopic TDPAD
technique and the DFT. Subsequently, a brief overview of the following electron
correlation based representative results will be presented: (i) spin
fluctuations of Fe in dilute Pd alloys [1], (ii) defect induced magnetism in
HOPG [2], (iii) Fe hyperfine field in the pnictide superconductor CaFe2As2
[3], and (iv) 3d impurities in Cr [4]. In addition, a recent macroscopic
study on quantum phase transitions in Pd-Ni nanoalloys [5] will also be
discussed.
References:
1. S.K.
Srivastava,S.N.
Mishra and G.P. Das,J. Phys.: Cond. Matter 18 (2006) 9463.
2. S.K. Mohanta,
S.N. Mishra, S.M. Davane, and S.K. Srivastava, J. Phys.: Cond. Matter 24
(2012) 085601.
3. S.K.
Mohanta, S.N. Mishra, S.M. Davane, N.
Kumar, A. Thamizhavel, S. Layek, Z. Hussain and S.K. Srivastava, Nucl. Instr.
Meth. Phys. Res. B 299 (2013) 71.
4. S.N.
Mishra and S.K. Srivastava, J. Phys.: Cond. Matter 20 (2008) 285204.
P. Swain, S.K. Srivastava and S.K. Srivastava,
Phys. Rev. B 91 (2015) 045401.
Prof. Adelung
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Kolloquiumsvortrag: N.N. / 27.11.15
27.11.2015 von 14:15 bis 15:45
Institut für Informatik, Ludewig-Meyn-Str. 2, Übungsraum 2
Titel: folgt
Abstract: folgt
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Kolloquiumsvortrag: Prof. Dr. Oleg Lupan, Technical University of Moldova / 30.11.15
30.11.2015 von 17:15 bis 18:45
Institut für Materialwissenschaft, Kaiserstr. 2, 24143 Kiel, Geb. D, Raum: "Aquarium"
Titel:
Nanostructuring
semiconducting oxides for nanodevices
Abstract:
Development of multifunctional nanosensors
based on new advanced functional nano-materials is in the focus of the research
community nowadays, since it is one of the
largest and fastest evolving market segment, with revenues expected to surpass
several trillion Euros soon. Scientific research on nano-materials contributes to miniaturization and
improvements in the size, detection range, reliability, selectivity and
sensitivity of existing solid-state sensors and light/image detectors, which
are the key components of many electronic and optoelectronic circuits. Nanodevices
which can perform multiple tasks are of high demand for intelligent portable
devices with small sizes (e.g. smartphones with environmental sensors) and
other applications (ranging from high-capacity
information storage to biochemical sensing, chemical and biological analysis,
and astronomy) due to very low power consumption and improved
performances.
Thus, research on semiconducting oxide nanocrystals will likely remain one of
the leading topics in condensed matter physics and advanced functional
materials science for many years. Looking beyond this field, nanostructuring nanocrystal systems
based on single or mixed phases of oxides have been assembled into designer
structures in a precisely chosen sequence. This creates opportunities to study
novel electrical, physical, and sensorial phenomena followed by implementation
in nanodevice applications which are not possible with ordinary bulk materials
and classical technologies.
In this talk, an overview across the field of semiconducting
oxides will be given, namely nano-ZnO, CuO, SnO2, MoO3,
and their nanostructuring by different nanotechnological approaches, which can
be scaled-up to industrial scale. The challenges to employ the properties of semiconducting
oxides on practical application grounds will be discussed and strategies will
be outlined for their fabrication, characterization, and nanodevice integration
by bottom-up technologies. Integration and applications in the single nanowire,
nanorod, tripod, and tetrapod as sensing devices and in special as
multifunctional nanosensors will also be discussed.
Furthermore, the contribution of crystalline
nanosensing and nanophotonical systems will be emphasized to act as an enabling
technology for scientific achievements in other research fields.
In this talk,
semiconducting oxides as main nano-blocks for nanodevices, namely our
contribution to building a new road to nanodevices from top-down to bottom-up
to hybrid nanotechnologies will be discussed.
Prof. Adelung
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Kolloquiumsvortrag: N.N. / 04.12.15
04.12.2015 von 14:15 bis 15:45
Institut für Informatik, Ludewig-Meyn-Str. 2, Übungsraum 2
Titel: folgt
Abstract: folgt
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Kolloquiumsvortrag: NN / 07.12.15
07.12.2015 von 17:15 bis 18:45
Institut Ostufer, Kaiserstr. 2, Geb. D Raum: "Aquarium
Titel: folgt
Abstract: folgt
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Kolloquiumsvortrag: N.N. / 11.12.15
11.12.2015 von 14:15 bis 15:45
Institut für Informatik, Ludewig-Meyn-Str. 2, Übungsraum 2
Titel: folgt
Abstract: folgt
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Kolloquiumsvortrag: Prof. Gabriella Andersson, Uppsala University, Schweden / 14.12.15
14.12.2015 von 17:15 bis 18:45
Institut für Materialwissenschaften, Kaiserstr. 2, Geb. D Raum: "Aquarium"
Titel:
Optimizing magnetic properties in the Materials Physics division at Uppsala University
Abstract:
After a brief introduction to
Uppsala University in general, there will be an overview of the research
activitiy in the Materials Physics division in the Department of
Physics and Astronomy. Our main three fields are
Magnetism, Soft Matter, and Hydrogen in Metals, and they all rely on
in-house synthesis of materials and a continuous chain of subsequent
experiments, from our own laboratories to large international
facilities. Since we have control from the beginning to
the end, we can find physical mechanisms behind the properties we
observe, and thus gain tools for optimizing the materials further, e.g.
through composition and placement of atoms.
After this review, I will
present some more specific examples of my research projects, which
concern optimization of magnetic properties in metallic thin films and
multilayers. The common theme is tuning of magnetic anisotropy
by composition and structure, and the materials are either amorphous
rare-earth-transition-metal compounds or epitaxial, i.e. crystalline,
multilayers where strain states are used as an additional tuning
possibility.
Prof. Selhuber-Unkel
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Kolloquiumsvortrag: N.N. / 18.12.15
18.12.2015 von 14:15 bis 15:45
Institut für Informatik, Ludewig-Meyn-Str. 2, Übungsraum 2
Titel: folgt
Abstract: folgt
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Kolloquiumsvortrag: Prof. Dr. Jürgen Kurths - Institute of Physics, Humboldt Universität zu Berlin / 11.01.16
11.01.2016 von 17:15 bis 18:45
Institut für Elektrotechnik und Informationstechnik, Kaiserstr. 2, 24143 Kiel, Geb. D Raum: "Aquarium"
Titel:
Synchronization in Complex Networks and Its Stability:
A Few Basics and some Applications
Abstract:
Synchronization phenomena are abundant in
nature, science, engineering and social life, but it was first recognized by
Christiaan Huygens in 1665 for coupled pendulum clocks; this was the beginning
of nonlinear sciences. In the last two decades, this concept has been
successfully extended to more complex systems, as the cardiovascular system or
teleconnections in the climate system. Complex networks were firstly studied by
Leonhard Euler in 1736 when he solved the Königsberger Brückenproblem. Recent
research has revealed a rich and complicated network topology leading to
interesting features of synchronization. Typical examples are the human brain,
power grids, arrays of coupled lasers and the Amazon rainforest. A crucial
problem is how stable synchronized regimes are in these systems against even
large perturbations. Here we claim that the traditional linearization-based
approach to stability is in several cases too local to adequately assess how
stable a state is. Instead, we quantify it in terms of basin stability, a new
measure related to the volume of the basin of attraction. This concept is
applied to power grids, to investigate how a grid's degree of stability is
influenced by certain patterns in the wiring topology. We mainly find that dead
ends and dead trees strongly diminish stability. This will be discussed for the
Northern European power system.
References: Pikovsky, A., M. Rosenblum, and J.
Kurths, Synchronization – A Universal Concept in Nonlinear Sciences, Cambridge
University Press 2001.
Arenas, A., A. Diaz-Guilera, J. Kurths, Y.
Moreno, and C. Zhou, Phys. Reports 2008, 469, 93. P. Menck, J. Heitzig, N.
Marwan, and J. Kurths, Nature Physics 9, 89 (2013)
P. Menck, J. Heitzig, J. Kurths, and H.
Schellnhuber, Nature Commun. 5, 3969 (2014)
P. Schultz, J. Heitzig, and J. Kurths, New
Journal Physics 16, 125001 (2014)
Y. Zou, T. Pereira, M. Small, Z. Liu, and J.
Kurths, Phys. Rev. Lett. 112, 114102 (2014)
Prof. Kohlstedt
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Kolloquiumsvortrag: N.N. / 15.01.16
15.01.2016 von 14:15 bis 15:45
Institut für Informatik, Ludewig-Meyn-Str. 2, Übungsraum 2
Titel: folgt
Abstract: folgt
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Kolloquiumsvortrag: Prof. Dr. Joachim Schnadt, Universität Lund, Schweden / 18.01.16
18.01.2016 von 17:15 bis 18:45
Institut für Materialwissenschaft, Kaiserstr. 2, 24143 Kiel, Geb. D Raum: "Aquarium"
Titel: (Near-)
Ambient pressure x-ray photoelectron spectroscopy: studying surface
chemical processes under realistic conditions and in real time
Abstract:
Surface
chemical processes play a ubiquitous role in our lives, whether this be
in industrial catalytic processes, controlled oxide and metal growth
processes of so great importance for e.g. the semiconductor industry, or
chemical reactions in our bodies: surfaces are always involved. To
investigate surface chemical processes there exists a large arsenal of
surface-sensitive techniques, and among them many spectroscopies which
can deliver elemental, chemical, and electronic information. However, in
their conventional form most surface-sensitive spectroscopy techniques,
such as x-ray photoelectron spectroscopy and x-ray absorption
spectroscopy, are limited to vacuum environments, which prevents the
study of ongoing surface chemical processes and which leads to decisive
information being missed. Ambient pressure x-ray photoelectron
spectroscopy has been adapted instrumentally to allow realistic or
close-to realistic pressures and thus allows in situ and operando
investigations of surface chemical processes. I will introduce the
technique and present cases from the areas of atomic layer deposition
(ALD) and chemical vapour deposition (CVD), aimed at gaining a true
understanding of what is going on during the growth of oxide layers on
semiconductors.
Prof. Selhuber-Unkel
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Kolloquiumsvortrag: Dagmar Kainmüller, Max-Planck-Institut für molekulare Zellbiologie und Genetik / 22.01.16
22.01.2016 von 14:15 bis 15:45
Institut für Informatik, Ludewig-Meyn-Str. 2, Übungsraum 2
Titel: Learning Deep Classifiers that integrate Prior Shape Knowledge for Bioimage Analysis
Abstract:
Deep Learning has rapidly
transformed the field of computer vision in the past years. To date,
deep convolutional neural networks (CNNs) outperform traditional machine
learning approaches in a vast number of applications.
However, little has been added to the theoretical understanding of CNNs
since they have been proposed more than 25 years ago. Furthermore, huge
sets of annotated data are necessary for successful training of deep
CNNs, while image analysis tasks often come
with small amounts of annotated data to learn from — especially in the
context of applications in biology.
In this talk I will explore
the theoretical relationship between CNNs and decision forests. Decision
forests are a hugely popular machine learning tool that can be trained
effectively in the face of small amounts of
annotated data. They are widely used for image analysis tasks in
biology. I will show that decision forests can be mapped to CNNs, which
allows for developing novel, easily interpretable deep CNN architectures
that can be trained from small amounts of data.
Prof. Carsten Meyer
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Kolloquiumsvortrag: Prof. Ludwig Schultz - IFW Dresden/TU Dresden / 25.01.16
25.01.2016 von 17:15 bis 18:45
Institut Materialwissenschaft, Kaiserstr. 2, 24143 Kiel, Geb. D, Raum: "Aquarium
Titel:
Interaction of
Ferromagnetic and Superconducting Permanent Magnets:
Superconducting Levitation
Abstract:
New means of urban transportation and logistics will
become realistic with superconducting magnetic bearings using bulk
high-temperature superconductors. The advantage of superconducting magnetic
levitation is that it is passively stable without any electronic control, but
with attracting and repelling forces to suspend a vehicle pendant or standing
upright from zero to high speed. These are perfect conditions for a rail-bound,
individual transport with cabins for 4 to 5 passengers, requested call by call.
They will levitate without noise over a track made of rare-earth permanent
magnets, saving energy and travel time. A big step forward in this vision has
been made in Dresden. The world largest research and test facility for
transport systems using bulk high-temperature superconducting material in the
levitation and guidance system, in combination with a permanent magnet track,
was put into operation. A vehicle for 2 passengers, equipped with linear drive
propulsion, noncontact energy supply, second braking system, and various test
and measurement systems is running on an 80 m long, oval driveway. In the
presentation, the principle of superconducting levitation by flux pinning in
high-temperature superconductors will be described. Based on this, an overview
of the SupraTrans II research facility and future directions of superconductivity-based
magnetic levitation and bearing for automation technology, transportation, and
medical treatment under enhanced gravity will be given. Also the
superconducting hoverboard, recently presented by Lexus, will be presented.
Prof. McCord
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Kolloquiumsvortrag: Prof. Dr. Ralf Hiptmair, ETH Zürich / 29.01.2016
29.01.2016 von 14:15 bis 15:45
Institut für Informatik, Ludewig-Meyn-Str. 2, 24118 Kiel, Übungsraum 2
Titel: Maxwell and the Hodge Laplacian
Abstract:
The linear Maxwell equations in frequency domain can be recast in several dierent forms,
as rst-order system, as second-order equation involving the double-curl operator, or a
second-order equation featuring the Hodge-Laplacian := curl curlgrad div.
Variational equations or boundary integral equations arising from these dierent formulations
are equivalent, but pose very dierent challenges when it comes to discretization.
For instance, there is the startling failure of smooth functions to be dense in
H0(curl; ) \H(div; ) for certain domains . This foils direct Galerkin discretization
of the Hodge-Laplacian and enforces the use of a mixed approach.
Similarly, rst-kind boundary integral operators associated with u = 0 display a strange
lack of coercivity. The culprit is the failure of certain combinations of boundary conditions
for to ensure uniqueness of solutions of the related boundary value problems.
Prof. Börm
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Kolloquiumsvortrag: Prof. Ralf Metzler, Universität Potsdam / 01.02.16
01.02.2016 von 17:15 bis 18:45
Institut für Materialwissenschaft, Kaiserstr. 2, Geb. D Raum: "Aquarium"
Titel: Ergodicity violation and ageing: From granular gases to living cells
Abstract:
In 1905 Einstein formulated the laws of diffusion, and in 1908 Perrin
published his Nobel-prize winning studies determining Avogadro's number from
diffusion measurements. With similar, more refined techniques the diffusion
behaviour in complex systems such as the motion of tracer particles in living
biological cells is nowadays measured with high precision. Often the diffusion
turns out to deviate from Einstein's laws. This talk will discuss the basic
mechanisms leading to anomalous diffusion as well as point out the physical
consequences. In particular the unconventional behaviour of non-ergodic,
ageing systems will be discussed within the framework of different stochastic
processes [1,2].
The effects of non-ergodicity and ageing will be analysed in detail for
specific physical systems such as the motion of particles in granular gases,
tracer diffusion in flexible gels and in living biological cells, as well
as in quenched energy landscapes. Moreover, many-particle effects with
interactions will be addressed.
[1] R. Metzler, J.-H. Jeon, A. G. Cherstvy & E. Barkai,
Phys. Chem. Chem. Phys. 16, 24128 (2014).
[2] E. Barkai, Y. Garini & R. Metzler, Phys. Today 65(8), 29 (2012).
Selhuber-Unkel
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Sonderkolloquiumsvortrag: Prof. Alex Huang, NC State University Raleigh, 03.02.16
03.02.2016 von 11:00 bis 12:00
Institut für Elektrotechnik und Informationstechnik, Kaiserstr. 2, Geb. D Raum: "Aquarium"
Titel: Energy Internet and Critical
Power Electronics Technology
Abstract:
Dr. Huang proposed the revolutionary
FREEDM (Future Renewable Electric Energy Delivery and Management) System in
2007 as a novel architecture suitable for plug-and-play of distributed
renewable energy and distributed energy storage devices. Motivated by the
success of the Information Internet, the architecture was put forward as a transformative
platform for an Energy Internet. In the
Information Internet, people share information in a plug and play manner. In
the envisioned ‘Energy Internet’, a vision for sharing of the energy is
proposed for ordinary citizen and home owners. Key enabling technologies
required to achieve such a vision will be discussed. Among many of the key
technologies, the development of advanced wide bandgap power semiconductor
devices and medium voltage power electronics systems will be discussed and
highlighted.
Liserre
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Absolventenfeier des Instituts für Informatik
05.02.2016 von 16:30 bis 20:00
Auditorium Maximum, Frederik-Paulsen-Hörsaal
Nähere Informationen finden Sie hier:
https://www.inf.uni-kiel.de/de/veranstaltungen/absolventenfeier
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Kolloquiumsvortrag: Prof. Dr.-Ing. Dr. med. Steffen Leonhardt - RWTH Aachen / 08.02.16
08.02.2016 von 17:15 bis 18:45
Institut für Elektrotechnik und Informationstechnik, Kaiserstr. 2, 24143 Kiel, Geb. D Raum: "Aquarium"
Titel: Methods for contact-free Monitoring of Vital Signs
Abstract:
After a short
introduction to the rationale for noncontact monitoring of vital signs, several
measurement modalities will be presented, including
- ballistocardiography
(BCG)
- contact-free
ECG monitoring
- contact-free
monitoring of pulse and breathing by magnetic induction
(MIM),
- contact-free
monitoring of temperature and breathing by Infrared Thermography (IRT), and
- contact-free
monitoring of perfusion, ventilation and oxygen saturation by reflective Pulse
Plethysmography Imaging (PPGI).
A comparison
of these methods with respect to penetration depths, modes of energy injection,
price, etc. will conclude the talk.
Prof. Schmidt
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Kolloquiumsvortrag: Prof. Dr. Jens Markus Melenk, TU Wien / 12.02.16
12.02.2016 von 14:15 bis 15:45
Institut für Informatik, Ludewig-Meyn-Str. 2, 24118 Kiel, Übungsraum 2
Titel: Stability and convergence of Galerkin discretizations of the Helmholtz equation
Abstract:
We consider boundary value problems for the Helmholtz equation at large
wave numbers $k$. In order to understand how the wave number $k$ affects
the convergence properties of discretizations of such problems,
we develop a regularity theory for the Helmholtz equation that is
explicit in $k$.
At the heart of our analysis is the decomposition of solutions into two
components: the first component is an analytic, but highly oscillatory
function and
the second one has finite regularity but features wavenumber-independent
bounds.
This new understanding of the solution structure opens the door to the
analysis of discretizations of the Helmholtz equation that are explicit
in their
dependence on the wavenumber $k$.
As a first example, we show for a conforming high order finite element
method
that quasi-optimality is guaranteed if (a) the approximation order $p$ is
selected as $p = O(\log k)$ and (b) the mesh size $h$ is such that
$kh/p$ is small.
The work is joint with Stefan Sauter (Zurich).
Prof. Steffen Börm
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Sonderkolloquiumsvortrag: Prof. Francesco Iannuzzo, Aalborg University/ 19.02.16
19.02.2016 von 12:15 bis 13:15
Institut für Elektrotechnik und Informaationstechnik, Kaiserstr. 2, 24143 Kiel, Geb. D Raum: "Aquarium"
Titel: Activities
on robustness of power devices at CORPE-
Aalborg University
Abstract:
Reliability
challenges in power electronics for modern wind power generation system are
pointed out, together with state-of-the-art testing and modelling techniques
adopted for robustness assessment of IGBT and SiC power modules under abnormal
conditions. Some details and case studies will be illustrated about running
activities in CORPE – center of power electronics at Aalborg university,
Denmark.
Prof. Liserre
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