HGS MathComp Curriculum & Events

Cancelled!!!

Physics-based simulation provides a powerful lens for studying human and animal motion. The characteristics of isolated muscle, and the architecture of musculotendons greatly influence the way biological systems prefer to move. Looking inside the body, joint contact forces and bone loads are dominated by the forces that muscles apply to the skeleton. This compact course will address the basics of musculotendon modeling in detail:

1. Phenomenological curves that define isolated muscle and tendon characteristics

2. 3 different Hill-type formulations

3. The good, the bad, and the ugly sides of Hill-type muscle models

If time permits we will also cover

5. 2 different ways to include muscles in a multibody model

6. 2 different ways to use muscles in an optimal control framework

Materials:
Pen & paper and a laptop with the following software
- Matlab installed
- Simbody installed :
https://github.com/simbody/simbody
- OpenSim installed :
https://github.com/opensim-org/opensim-core

Lectures:
March 31 - April 2 @ 10:30-12:00
Tutorial:
March 31 - April 2 @ 13:00-15:00
pen & paper, Matlab, and OpenSim exercises

Target Group:
Doctoral students, master_s students, and postdoctoral associates in the mathematical, physical, and engineering sciences

Aims of the course:
The course will introduce students to the theory of total positivity, with concentration on totally positive kernels. The course will emphasize the connections between totally positive kernels and the areas of mathematical statistics, probability inequalities, linear algebra, analysis on the group of unitary matrices, and finite reflection groups. The prerequisites for the course are a strong undergraduate degree in the mathematical or physical sciences.

Course content:
The course will introduce the theory of total positivity with motivating material based on the classic monographs by F. R. Gantmacher and M. G. Krein (\"Oscillation Matrices and Kernels and Small Vibrations of Mechanical Systems\", 2002, revised edition) and S. Karlin (\"Total Positivity,\" 1968).
The second part of the course will cover properties of totally positive kernels and provide applications to probability inequalities arising in mathematical statistics. We will apply methods from linear algebra (such as the Binet-Cauchy principle) and multivariable calculus to ascertain the totally positive properties of specified kernels.
In the third and last part of the course, the lectures will study generalizations of totally positive kernels. The material treated in this section of the course will reveal that there are close connections between the theory of total positivity and harmonic analysis on the group of unitary matrices.

Please register here:

Compact Course Schedule:

June 11, 9:00-10:30 Room 520
June 12, 9:00-10:30 & 14:00-16:00 Room 532
June 15, 9:00-10:30 & 11:00-12:00 Room 532
June 16, 9:00-10:30 Room 520
June 17, 9:00-10:30 & 14:00-16:00 Room 432

The term “Uncertainty Quantification” is as old as the disciplines of probability and statistics, but as a field of study it is newly emerging. It combines probability and statistics, with mathematical and numerical analysis, large-scale scientific computing, experimental data, model development and application sciences to provide a computational framework for quantifying input and response uncertainties which ultimately can be used for more meaningful predictions with quantified
and reduced uncertainty.

We will motivate the central questions in computational uncertainty quantification through some illustrative examples from subsurface flow,
weather and climate prediction, material science, nuclear reactor physics and biology. The key challenge that we face in all those
applications is the need for fast (tractable) computational tools for high-dimensional quadrature. After a short overview of the available techniques, we study sampling-based approaches in more detail. We put a particular emphasis on multilevel (or multiscale) methods that exploit the natural model hierarchies in numerical methods for partial differential equations. In the final part of the course, we will briefly consider the inverse problems of Bayesian inference, data assimilation and filtering and show how the multilevel techniques presented in the earlier parts of the course can be extended to these more challenging tasks.

A rough outline of the course is:

- Introduction: What is Uncertainty Quantification?
- Motivating Examples from the Earth Sciences, Material Sciences,

Physics and Biology
- High-dimensional quadrature and tractability
- Uncertainty Propagation: “The Forward Problem” Sampling-based approaches
- Basic Monte Carlo Simulation
- Quasi-Monte Carlo Methods
- Multilevel Monte Carlo Methods
- Stochastic Collocation and Polynomial Chaos
Uncertainty Quantification: “The Inverse Problem\"
- Bayes’ Rule and Bayesian Inference
- Markov Chain Monte Carlo
- Multilevel Bayesian Inference
- Future perspectives: Data Assimilation and Filtering

Target group

Doctoral students, postdocs and master students with an interest in reliable scientific computing.


Aims of the course

The aim of the course is to give a basic, hands-on introduction to the evolving field of large scale uncertainty quantification, with a particular emphasis on novel sampling based approaches for high dimensional parameter spaces. Using the tools and techniques addressed in the course, students should be able to decide independently which computational approaches are most suited to a given problem and carry out simple uncertainty quantification studies in their field of study. They should also be able to give a basic assessment of the complexity of the various approaches and assess their feasibility in a given situation.

slides UQ

Please register here.

IWR-Colloquium Summer Term 2015

The field of computational origami is focused on the development of algorithms for origami design: construct a fold pattern that meets specific objects for the 2D unfolded form, the 3D folded form, and in some case, the phase­space path for transitioning between the two. In this talk I will present several recent developments in origami design algorithms and will show examples of their construction, some rendered in pixels, some rendered in paper.

Robert J. Lang is recognized as one of the foremost origami artists in the world as well as a pioneer in computational origami and the development of formal design algorithms for folding. With a Ph.D. in Applied Physics from Caltech, he has, during the course of work at NASA/Jet Propulsion Laboratory, Spectra Diode Laboratories, and JDS Uniphase, authored or co­authored over 100 papers and 50 patents in lasers and optoelectronics as well as authoring, co­authoring, or editing 14 books and a CD­ROM on origami. He is a full­time artist and consultant on origami and its applications to engineering problems but keeps his toes in the world of lasers, most recently as the Editor­in­Chief of the IEEE Journal of Quantum Electronics from 2007-2010. He received Caltech’s highest honor, the Distinguished Alumni Award, in 2009 and was elected a Fellow of the American Mathematical Society in 2013.

Thematic Scope:
* Short recapitulation of basics of object-oriented programming in C++ (classes, methods, operators)
* Memory management (variables, references, pointers)
* Constant values and objects
* Error handling (exceptions)
* Inheritance
* Dynamic polymorphism (virtual inheritance)
* Static polymorphism (templates)
* The Standard Template Library (STL containers, iterators and algorithms)
* Traits
* Policies
* Template metaprogramming
* Expression templates
* C++11 threads
The lectures are designed to give insight into new developments and possibilities due to the C++11 standard. If time permits, the parts concerning C++11 will be extended and code excerpts taken from the DUNE project will be used to illustrate real-world application of the language constructs.

We kindly invite all members, students and staff of the IWR and the HGS MathComp to join us at our 2015 summer party.

As usual, in accordance with university guidelines, we have to charge 10,- EUR per person to cover expenses - children attend free of charge.

Please make sure to register online for the event.

Online Registration

HGS MathComp Public Lecture

The last decade of this past century has been witness to a revolution in the development and application of mathematical techniques to origami, the centuries-old Japanese art of paper-folding. The techniques used in mathematical origami design range from the abstruse to the highly approachable. In this talk, I will describe how geometric concepts led to the solution of a broad class of origami folding problems – specifically, the problem of efficiently folding a shape with an arbitrary number and arrangement of flaps, and along the way, enabled origami designs of mind-blowing complexity and realism, some of which you’ll see, too. As often happens in mathematics, theory originally developed for its own sake has led to some surprising practical applications. The algorithms and theorems of origami design have shed light on long-standing mathematical questions and have solved practical engineering problems. I will discuss examples of how origami has enabled safer airbags, Brobdingnagian space telescopes, and more.

Robert J. Lang is recognized as one of the foremost origami artists in the world as well as a pioneer in computational origami and the development of formal design algorithms for folding. With a Ph.D. in Applied Physics from Caltech, he has, during the course of work at NASA/Jet Propulsion Laboratory, Spectra Diode Laboratories, and JDS Uniphase, authored or co-authored over 100 papers and 50 patents in lasers and optoelectronics as well as authoring, co-authoring, or editing 14 books and a CD-ROM on origami. He is a full-time artist and consultant on origami and its applications to engineering problems but keeps his toes in the world of lasers, most recently as the Editor-in-Chief of the IEEE Journal of Quantum Electronics from 2007-2010. He received Caltech’s highest honor, the Distinguished Alumni Award, in 2009 and was elected a Fellow of the American Mathematical Society in 2013.

Digital art history is considered to be part of the discipline of art history as well as part of digital humanities as digitally based methods require an interdisciplinary approach. In short, this means using digital infrastructures and tools, but also critically reflecting upon their usage and understanding the technical background (quoted from “Memorandum zur digitalen Kunstgeschichte in der Lehre” (memorandum on digital art history in education)). Digital art history is not only faced with the challenge of analysing objects as primarily art historical research subjects not only in the context of increasingly mimetic digital representations, but also of embedding these representations in the semantic and stylistic contexts of the artwork. In order to succeed in these challenges, immediate access to the visual information of the digital representation, as well as access to virtual research environments which will help to depict semantic relations, is required.

Starting with the digital representation of the artwork, the summer school for digital art history demonstrates ways of processing the artwork visually, iconographically and contextually. The focus is on new methods of annotation and image analysis. Up until now nearly all steps of digital image exploitation were left up to various experts: content processing was the task of student assistants and often highly qualified art historians whereas the creation of new digital records only concerned IT specialists or ambitious self-educated scholars. New exploitation strategies, such as crowd sourcing, machine learning and computer vision, provide the specialist with algorithms/artificial intelligence and laypersons that enable effective mass processing of image data. In addition, new collaborations and interdisciplinary links are forming between the classical scientific fields. The digital image is not only described, but also analysed in terms of content and compared with others. These processes must be developed and critically monitored.

! ATTENTION: REGISTRATION REQUIRED !
Please refer to the website of the event and contact Dr. Peter Bell at bell@uni-heidelberg.de for more information.

Eine nachhaltige und effiziente Energieversorgung ist ein zentraler Standortfaktor für die österreichische und europäische Wirtschaft. Daher wird die Energieeffizienz in der Industrie als zentrales strategisches Thema am AIT Austrian Institute of Technology etabliert. Im Vordergrund stehen hier Technologien zur Erhöhung der Energieeffizienz durch Wärmerückgewinnung, Abwärmenutzung und den Einsatz thermischer Energiespeicher sowie die Optimierung von Betriebsstrategien mit Hilfe dynamischer Prozessmodelle und Simulation. Der Vortrag gibt einen Überblick über die aktuellen F&E Aktivitäten im Bereich Energieeffizienz in der Industrie.

I will present a trust-region algorithm with adaptive sparse grids for the solution of optimization problems governed by partial differential equations (PDEs) with uncertain coefficients. The algorithm adaptively builds two separate sparse grids: one to generate optimization models for the optimization step computation, and one to approximate the objective function to evaluate whether to accept the step. The quality of the adaptive sparse grid models is determined by the trust-region algorithm. Conditions on inexact function and gradient evaluations in previous trust-region frameworks are extended to allow the rigorous use of asymptotic (discretization) error estimates for objective function and gradient approximations.

The algorithm often generates adaptive sparse grids that contain significantly fewer points than the high-fidelity grids, which leads to a dramatic reduction in the computational cost. Moreover, the numerical results indicate that the new algorithm rapidly identifies the stochastic variables that are relevant to obtaining an accurate optimal solution. When the number of such variables is independent of the dimension of the stochastic space, the algorithm exhibits near dimension-independent behavior.

Excerpt from Abstract:

"The Data Vortex network enables scientists to perform work on problems that rely on a tremendous flood of processor-to-processor communication, something that present-day computers handle quite poorly. For example, the Data Vortex is used to perform the FFT algorithm. In 1805, Karl Friedrich Gauss used the Fast Fourier Transform to determine the trajectories of the comets Pallas and Juno. It is of note that the original manuscript of Fourier on the subject of Fourier analyses appeared in 1807. The Gauss work describes the data flow of the transform. It is of interest that the Data Vortex computer enables this FFT data flow on a general purpose computer for the first time. This topic of FFT data flow as well as the general topic of data flow algorithms on Data Vortex computers will also be discussed.

Dr. Reed’s talk will be followed by a brief overview of the Data Vortex family of high performance computers currently being manufactured by Plexus, Inc. This overview, given by Mr. Bill Stube, Data Vortex Project Manager for Plexus, Inc., will include a high-level description of the Data Vortex enabled system characteristics, performance comparisons to present-day leading supercomputer systems, and an overview of the simple programming model used by Data Vortex researchers to port their work onto Data Vortex computers."

Full Abstract
Biographie Dr. Coke Stevenson Reed
Website Data Vortex Technologies

Cut cells methods have been developed in recent years for
computing flow around bodies with complicated geometries. They are an
alternative to body fitted or unstructured grids, which may be harder to
generate and more complex in the bulk of the flowfield. Cut cell methods
\"cut\" the flow body out of a regular Cartesian grid. Most of the grid is
regular. Special methods must be developed for the \"cut cells\", which are
cells that intersect the boundary. Cut cells can have irregular shape and
may be very small. We present a mixed explicit implicit time stepping
scheme for solving the advection equation on a cut cell mesh. The scheme
represents a new approach for overcoming the small cell problem: namely,
that explicit time stepping schemes are not stable on the arbitrarily
small cut cells. Instead, we use an implicit scheme near the embedded
boundary, and couple it to a standard explicit scheme used over most of
the mesh. We compare several ways of coupling the explicit and implicit
scheme, and prove a stability (TVD) result for one of them, which we call
“flux bounding”. We present numerical results in one, two, and three
dimensions. These results show second-order accuracy in the $L^1$ norm and
between first- and second-order accuracy in the $L^{\\infty}$ norm. (Joint
work with Marsha Berger.)

Im letzten Jahr haben wir Sicherheit erhalten, dass mehrere staatliche Institutionen verschiedener Länder den kompletten Internetverkehr überwachen und analysieren. Es drängt sich die Frage auf, wie man seine Daten vor unerlaubtem Zugriff schützen und seine Privatsphäre bewahren kann. Deswegen veranstalten wir sogenannte Cryptopartys, auf denen wir technische Hilfsmittel erklären, mit denen man seine Kommunikation verschlüsseln kann – ohne, dass man ein Computerexperte sein muss.

Die Veranstaltungen sind kostenlos und stehen jedem offen, um Anmeldung wird gebeten (siehe unten).

Was ist eine Cryptoparty?
Auf einer Cryptoparty zeigen wir, dass man kein Computerfreak sein muss, um seine E-Mails zu verschlüsseln. Wir zeigen, wie man etablierte Verchlüsselungs- oder Anonymisierungssoftware installiert und benutzt. Ist diese Software einmal eingerichtet, fällt sie im Alltag kaum noch auf, aber kann Kommunikation effektiv schützen. Teilnehmer können gerne einen eigenen Laptop mitbringen, dann unterstützen wir bei der Installation und Einrichtung.

Anmeldung
Damit wir vorbereiten und planen können, bitten wir um eine kurze und formlose Anmeldung an crypto@noname-ev.de mit der Anzahl der Personen, welcher Termin und, wenn Laptops mitgebracht werden, des verwendeten Betriebssystems. Danke!


Wer seid ihr?
Der NoName ist ein Heidelberger Treff zu computer- und techniknahen Themen aus dem erweiteren Umfeld des Chaos Computer Club. Wir treffen uns jeweils am ersten Donnerstagabend im Monat zu einem Stammtisch in wechselnden Lokalen und an allen anderen Donnerstagen in einem Raum an der Universität.
Bei der Durchführung unterstützen uns dieses Jahr freundlicherweise die HGS MathComp und die AG Netzpolitik der Universität Heidelberg. Vielen Dank!

Serious cases of scientific misconduct have been reported in the media recently. But beside the most prominent cases several shades of questionable scientific practice might undermine the integrity of the sciences. Based on the recommendations for “Safe Guarding Good Scientific Practice” by the Deutsche Forschungsgemeinschaft this course wants to support doctoral students to develop a responsible professional conduct as a researcher.
In this one-day workshop you will gain a general understanding of good scientific practice and scientific misconduct (e.g. plagiarism, fabrication, falsification). We will explore key areas of conflict, critical situations and possible causes of misconduct. Questions regarding data management, documentation and ownership will be addressed, as well as the correct use of references and problem areas in the publication process. Furthermore we will reflect on aspects of a functioning supervisor- student- relationship as a factor to prevent scientific misconduct.

Please register here:
here

An important part in research is presenting your results. This course will help you to prepare for the presentation of your research in seminars, at conferences or in your disputation. In the course we will work on the following topics:
-How do I structure my talk to make it more effective?
-How do I use media efficiently?
-What do I have to bear in mind to address my audience most effectively?
-How can I improve my performance through feedback?
The course requires participants to be actively involved by giving a presentation. Therefore you are expected to prepare a short presentation/poster on your research topic beforehand / after the first day of the workshop.
Systematic feedback (from the group, the expert, and video) will help you to recognize your strengths and weaknesses, to try out new presentation strategies and thus to improve your presentation skills.
Please note: This is not a language course.
Please register
here