Inverse Problems in Wave Propagation  IWaP 2015
Aims and Scope
The workshop on Inverse Problems in Wave Propagation (April 710, 2015) aims to gather researchers working in the broad field of inverse problems linked to partial differential equations, providing a place to discuss novel methods, current directions, and future trends in the field.
The workshop highlights in particular the mathematical and numerical analysis of methods tackling inverse problems linked to timeharmonic or timedependent wave equations. Topics include for instance parameter identification for complex systems governed by differential equations, iterative and qualitative methods in inverse scattering, integral equation methods, optimization techniques, inverse eigenvalue problems, as well as the application of inversion algorithms in scientific, engineering, or industrial problems.
Place and Date
The workshop takes place at the University of Bremen, Germany, during the week after Easter 2015 (Tuesday 7.4.2015 until Friday 10.4.2015).
Organizers
The workshop is organized by the Workgroup on Inverse Problems at the Center of Industrial Mathematics of University of Bremen.
Acknowledgements
IWaP2015 is supported by the Center of Industrial Mathematics of University of Bremen as well as by the Exploratory Project InsideOutsideDuality and Nondestructive Testing granted by the University of Bremen in the framework of its institutional strategy, funded by the excellence initiative of the federal and state governments of Germany.
Registration
Participation in the workshop is free of charge. To simplify the organization of the workshop we nevertheless insist that all participants register in advance by sending a short email to Stefan Peters.
Please tell us until March 1, 2015, whether you would like to give a talk and, if so, indicate the title of your talk. Since the number of talks is limited we might be forced to make a selection among the proposed talks, following a firstcomefirstserve rule.
The workshop features a poster session. Please tell us until March 26, 2015, whether you intend to present a poster and, if so, indicate the title of your poster. There is no limit for posters and the session will be informal.
Schedule

Tuesday April
7 
Wednesday April
8 
Thursday April
9 
Friday April
10 
09:00 10:45 
R.
Kress L.
Mindrinos 
E. Lakshtanov Z. Jiang 
P. Monk G. Hu 
T.
Arens X.
Liu 

Coffee
break 
Coffee
break 
Coffee
break 
Coffee
break 
11:15 12:05 
T. Hohage 
F. Cakoni 
D. Colton 
A. Kirsch 

Lunch 
Lunch 
Lunch 
Lunch 
13:30 15:15 
M. Kray L. Bourgeois 
R. Griesmaier N. Hyvönen 
J. Sun A. Kleefeld 


Coffee
break 
Coffee
break 
Coffee
break 

15:45 17:30 
J.
Piontkowski H. Haddar 
T.
Helin L. Chesnel 
Poster Session 

19:00 


Workshop
dinner 

Talks (in the order of the schedule)
 R. Kress: Iterative Solution of an inverse source problem
 L. Mindrinos: The inverse scattering problem in quantitative multimodal tomography
 T. Hohage: Variational source condiitions and stability for inverse medium scattering problems
 M. Kray: Wave splitting for timedependent scattered field separation
 L. Bourgeois: The method of quasireversibility for timedependent wave equation. Application to the inverse obstacle problem
 J. Piontkowski: Reconstruction of the stored energy function of a certain class of hyperelastic materials from partial Cauchy data
 H. Haddar: A sampling method for differential measurements with unknown background
 E. Lakshtanov: Explicit methods for solving inverse problems
 Z. Jiang: Computing interior eigenvalues of domains from far fields
 F. Cakoni: On the direct and inverse scattering problem for periodic media
 R. Griesmaier: Multifrequency MUSIC for electrical impedance tomography
 N. Hyvönen: Stochastic finite element method for electrical impedance tomography
 T. Helin: Inverse scattering in halfspace with random boundary conditions
 L. Chesnel: Nonscattering wavenumbers and far field invisibility for a finite set of incident/scattering directions
 P. Monk: Time domain linear sampling method
 G. Hu: Nearfield imaging of scattering obstacles with the factorization method
 D. Colton: Transmission eigenvalues for spherically stratified media
 J. Sun: Reconstruction of an inhomogeneity in planar waveguide using finite elements
 A. Kleefeld: Estimating the refraction index from the knowledge of interior transmission eigenvalues
 T. Arens: Characterizing nonscattering inhomogeneities for electromagnetic waves
 X. Liu: Inverse acoustic scattering by impenetrable cavities
 A. Kirsch: The Born approximation for the wave equation
Location
The workshop takes place in the university building MZH (Mehrzweckhochhaus), the largest building in the central area on the campus. Our rooms on the first floor are MZH 1460 and MZH 1470. All university facilities and university restaurants are nearby.
Here is a map of the university and its surroundings and a list of shops on campus.
Accomodation
There are three hotels on or close to campus:
 The 7THINGS is directly on campus, see this page for its location.
 The Atlantik Hotel Universium, is directly next to campus, see this page for its location.
 The Hotel Munte, is about 5 minutes away from the location of the workshop (walking distance), see this page for its location.
Public Transportation
Bremen has a very well developed public transportation system and we strongly encourage you to use it whenever going, e.g., into town, to the railway station, or to the airport. Maps of the tram and bus system in the city of Bremen can be found here and timetable information is available here.
Purchasing Tickets for the Tram
You can purchase your ticket at a ticket vending machine inside the tram. The ticket machines provide instructions in English and accept banknotes up to 50€ notes. You have to purchase an adult single ticket (EinzelTicket Erwachsene) for 2.50€. If you plan to use the tram frequently, you can buy a ticket for seven days for 20,00€ or ten single tickets for 22,50€ at the BSAG ticket shop outside the central train station or at the university at Onkel Walter's shop in the central Glashalle (glass hall), see the maker GH in square C2 on the campus plan www.unibremen.de/universitaet/dieuniimueberblick/lageplan.html.
How to Get into Campus
 Tram line number 6 direction “Universität” takes you directly from the central train station and from the Bremen city airport to the university campus (stop "Universität Zentralbereich")
 You can also take the following busses (get off at the stop "Universität Zentralbereich"):
 no. 21 direction “Universität”,
 no. 22 direction “UniversitätLehe”
 no. 31 direction “Upper Borg”
 no. 630 direction “Zeven” or “Tarmstedt” (this is a fast connection)
 no. 670 direction “Worpswede” (this is a fast connection)
Arrival
Arriving by Plane or by Train
 When arriving at the Airport Bremen or at the Central Railway Station (Bremen HBF), then take the tram line 6 in direction “Universität”. This line directly goes into campus and takes about 40 Minutes from the ariport and 20 Minutes from the railway station. It is the fastest and cheapest way to get to campus. Get off at the tram stop “Universität Zentralbereich”.
 Taxi stands can be found both outside the airport and the central station
Arriving by Car
 From the autobahn A1 change at "Bremer Kreuz" to the A27, direction "Cuxhaven/Bremerhaven"
 Take exit number 19 "HornLehe/Universität", follow the direction „Centrum/ Universität“
 At the second intersection turn right into "Universitätsallee" ("University Alley")
 At the next traffic light turn right again into the the "EnriqueSchmidtStraße". Use the the parking lot there. The parking fee is 0.70 Euro per day.
Participants
Florian Bürgel  University of Bremen 
Zixian Jiang  INRIA Saclay 
Armin Lechleiter  University of Bremen 
Frederieke Miesner  University of Bremen 
Stefan Peters  University of Bremen 
Marcel Rennoch  University of Bremen 
Tobias Rienmüller  University of Bremen 
Laurent Bourgeois  ENSTA Paristech, Palaiseau 
Evgeny Lakshtanov  University of Aveiro 
Hanaa HACHIMI  Ibn Tofail University 
Leonidas Mindrinos  University of Vienna 
Thorsten Hohage  University of Göttingen 
Houssem Haddar  INRIA Saclay IledeFrance 
David Colton  University of Delaware 
Fioralba Cakoni  University of Delaware 
Peter Monk  University of Delaware 
Jiguang Sun  Michigan Technological University 
Tilo Arens  Karlsruher Institut for Technology (KIT) 
Rainer Kress  University of Göttingen 
Julia Piontkowski  University of Saarland 
Marie Kray  University of Basel 
Guanghui Hu  Weierstrass Institute 
Anna Trull  TU Delft 
Xiaodong Liu  Chinese Academy of Sciences 
ThiPhong Nguyen  Polytechnique Paris 
Erdem Altuntac  University of Goettingen 
Lucas Chesnel  Ecole Polytechnique 
Andreas Kirsch  Karlsruher Institut fuer Technologie 
Andreas Kleefeld  BTU Cottbus 
Simon Maretzke  University of Göttingen 
Frederic Weidling  University of Göttingen 
Florian Boßmann  University of Göttingen 
Tapio Helin  University of Helsinki 
Roland Griesmaier  Universität Würzburg 
David James  University of Göttingen 
Zixian Jiang  Ecole Polytechnique Paris 
Shobha Monnanda Erappa  University of Goettingen 
Christian Kruschel  University of Goettingen 
Kenneth Chijioke Duru  University of Stanford 