NA Digest, V. 21, # 32

NA Digest Sunday, August 22, 2021 Volume 21 : Issue 32

Today's Editor:

Daniel M. Dunlavy
Sandia National Labs

Today's Topics: Subscribe, unsubscribe, change address, or for na-digest archives:

Submissions for NA Digest:

From: Sven Leyffer
Date: August 19, 2021
Subject: Nomination for ICIAM Prizes

The deadline for nominations for ICIAM prizes ia September 1, 2021.
The following ICIAM Prizes are awarded every four years the the ICIAM
Congress, see also

- ICIAM Industry Prize for outstanding contributions to innovative
mathematical techniques with demonstrated impact in Industry.
- Olga Taussky-Todd Lecture is awarded to a woman who has made
outstanding contributions in applied mathematics and/or scientific
- ICIAM Su Buchin Prize recognizes outstanding contribution in the
application of mathematics to emerging economies and human
- ICIAM Pioneer Prize for introducing applied mathematical methods and
scientific computing techniques to an industrial problem area or a
new scientific field of applications.
- ICIAM Maxwell Prize in recognition of a mathematician who has
demonstrated originality in applied mathematics.
- ICIAM Lagrange Prize recognizes mathematicians who have made an
exceptional contribution to applied mathematics throughout their
- ICIAM Collatz Prize recognizes an individual under 42 years of age
for outstanding work on industrial and applied mathematics.

Nomination are accepted online at

Sven Leyffer, ICIAM Secretary

From: Paul Van Dooren
Date: August 18, 2021
Subject: Reminder, Call for Nominations, Hans Schneider Prize, Due Sep 2021

The 2022 Hans Schneider Prize in Linear Algebra Committee has been
appointed by the ILAS President upon the advice of the ILAS Executive
Board. It consists of: Rajendra Bhatia, Anne Greenbaum, Leslie Hogben,
Martha Takane, Paul Van Dooren (chair) and Daniel Szyld (ILAS
president - ex-officio member).

It is the responsibility of the committee to solicit nominations and
to make a recommendation to the ILAS Executive Board for this Prize to
be awarded at the ILAS 2022 meeting in Galway.

Nominations of distinguished individuals judged worthy of
consideration for the Prize, are now being invited from members of
ILAS and the linear algebra community in general. In nominating an
individual, the nominator should include: (1) a brief biographical
sketch, and (2) a statement explaining why the nominee is considered
worthy of the prize, including references to publications or other
contributions of the nominee which are considered most significant in
making this assessment.

The prize guidelines can be found at
and the list of all Hans Schneider Prize winners at

Nominations are open until September 30, 2021 and should be sent by
email to the chair, Paul Van Dooren (
The committee may ask the nominator to supply additional information.

From: Robert van de Geijn
Date: August 22, 2021
Subject: Online Materials for Linear Algebra and HPC

We continue to offer (free to auditors) four MOOCs on that may
be of interest to the NADigest community. Related materials, which
include short videos, exercises with complete solutions, and
activities, are also made available for free independent of these
courses. They can be used for self-study, as a supplement to
tradition textbooks, or as an alternative to such textbooks. They may
also be useful to students who wish to review as the semester starts.

- Advanced Linear Algebra: Foundations to Frontiers (ALAFF) is a
full-semester graduate course on numerical linear algebra.

- Linear Algebra: Foundations to Frontiers (LAFF) is a full-semester
undergraduate introduction to linear algebra designed with those
interested in computing in mind.

- LAFF-On Programming for Correctness is a 6 week course that teaches
some of the core mathematics that underlies reasoning about
programming, with an application to matrix computations. The
techniques have been key to the development of our libflame library,
an alternative to LAPACK.

- LAFF-On Programming for High Performance is a 4 week course that
uses matrix-matrix multiplication to teach core ideas of
HPC. Learners discover some of the basic techniques that underlie
the BLAS-like Library Instantiation Software (BLIS) framework. A
related paper received the SIAM Activity Group on Supercomputing
Best Paper Prize in February 2020.

The courses are discussed in the SIAM News article "Teaching Numerical
Linear Algebra Online"

For additional information, visit

From: Jianlin Xia
Date: August 21, 2021
Subject: SuperDC 1.0.0: Eigenvalue decomp, nearly linear complexity

SuperDC 1.0.0 -- stable divide-and-conquer eigenvalue decomposition
package (in Matlab) for rank-structured Hermitian matrices with about
O(n) complexity has been released. See the following link for more

Applicability: rank-structured Hermitian matrices
(represented/approximated by HSS forms). Examples:
- Banded matrices
- Toeplitz matrices (in Fourier space)
- Some discretized integral equations
- Schur complements in direct factorizations of some sparse matrices
- Other dense or sparse matrices with small off-diagonal (numerical)

- No tridiagonal reduction needed
- Nearly linear complexity for full eigenvalue decomposition
- Nearly linear storage for all eigenvectors
- Many stability features (stabilization like in tridiagonal
divide-and- conquer, safeguards for clustered eigenvalues, stable
FMM, etc.)
- User controllable accuracy

From: Paul Martin
Date: August 15, 2021
Subject: New Book, Time-Domain Scattering

My book on "Time-domain scattering" has been published by Cambridge
University Press: details here:

The book discusses analytical and numerical methods for scattering
problems in the time domain. The prototype problem is: diffraction of
a sound pulse by a sphere.

From: Marta D'Elia
Date: August 17, 2021
Subject: RAMSES Italy/HYBRID, Dec 2021

With this message, we (re)announce the workshop RAMSES (Reduced order
modeling, Approximation theory, Machine learning, Surrogates,
Emulators and Simulators) to be held in a HYBRID format at SISSA in
Trieste, Italy, on December 14-17, 2021.

The workshop is focused on a review of recent algorithmic and
mathematical advances and the development of new research directions
in RAMSES, in the context of parametrized partial differential
equations with sparse and noisy data in high-dimensional parameter
spaces. The format of the workshop includes INVITED PRESENTATIONS and

The confirmed invited speakers are: H. Antil (George Mason
University), M.A. Bessa (TU Delft), P. Bochev (Sandia National
Laboratories), C. Carstensen (Humboldt University), S. Canic (UC
Berkely), Q. Du (Columbia University), O. Dunbar (California Institute
of Technology), J. Hesthaven (EPFL), A. Huerta (Universitat
Politecnica de Cataluna). G.E. Karniadakis (Brown University),
Y. Maday (Universite Pierre et Marie Curie) H. Najm (Sandia National
Laboratories), B. Peherstorfer (NYU) S. Perotto (Politecnico di
Milano), A. Quaini (University of Houston), F. Rizzi (NexGen
Analytics), R. Smith (North Carolina State University), E. Ullman (TU
Munich), R. Ward (UT Austin) C. Webster (UT Austin) Y. Yu (Lehigh

ALL invited talks will be delivered via Zoom, including those that are
also delivered in a face-to-face format. We invite other researchers,
most especially students and postdocs, that are already active in
RAMSES-related research to participate in the workshop via a VIRTUAL
POSTER which consists of a 5 minute Zoom presentation and online
availability of all posters. The posters of participants who attend
the workshop in person will also be available for in-person viewing by
other in-person participants at the workshop. Poster abstracts should
be submitted to in text format indicating: Name,
affiliation, email address, title, abstract.

From: Daniel Kressner
Date: August 18, 2021
Subject: Head of Laboratory/Professorship Position, PSI/EPFL, Switzerland

PSI and EPFL are jointly seeking to appoint a dynamic personality with
strategic thinking abilities as Head of the Laboratory for Simulation
and Modeling (LSM) at PSI, and as tenured Full Professor of Applied
and Computational Mathematics at EPFL.

The PSI is Switzerland's largest research institute for natural and
engineering sciences, and a world leading user laboratory. It develops
and operates large-scale research infrastructures that require
exceptionally high standards of know-how and technology.

EPFL is a leading university with a strong emphasis on basic science,
engineering, and life sciences. Research and teaching within its
School of Basic Sciences includes computational mathematics,
high-performance computing, large-scale simulation, and scientific
data analysis.

Further details of the position can be found at

Applications should be submitted in via
by October 31 2021.

EPFL and PSI are equal opportunity employers and family friendly
institutions. They are committed to increasing the diversity of their
faculty and staff. They strongly encourage women and members of ethnic
minorities to apply.

From: Lina Zhao
Date: August 18, 2021
Subject: Postdoc Position, NA/Comp Math, City Univ of Hong Kong

A postdoctoral position is available in the research group of Dr. Lina
Zhao at the City University of Hong Kong. Candidates with research
experience in numerical analysis, PDEs, machine learning are all
welcome to apply. The postdoctoral position is supported by Hong Kong
Centre for Cerebro- Cardiovascular Health Engineering
(, and it can be a 3-year contract and can
start at any time before the end of 2021. Competitive salary will be
provided. If you are interested, please send your CV (with a
publication list) to Dr. Zhao directedly (E-mail address: for an application.

From: Stephen Becker
Date: August 16, 2021
Subject: Postdoc Position, Scientific Data Compression, UC Boulder

Applications are invited for a postdoctoral position available in Fall
2021 jointly in the Applied Mathematics and Smead Aerospace
Engineering Sciences departments at the University of Colorado,
Boulder. The appointee will conduct fundamental research in broad
areas of large-scale PDE data compression using advanced techniques
from machine learning, PDE discretization, and parallel computing. The
project is a collaboration between Profs. Stephen Becker (Applied
Math), Alireza Doostan (Aerospace), John Evan (Aerospace), and Kenneth
Jansen (Aerospace).

Applicants must have a Ph.D. in areas related to applied mathematics
and computational sciences or engineering. Preference will be given to
candidates with expertise in areas including but not limited to
randomized linear algebra, deep learning, and/or high order PDE
discretization schemes.

The position is for two or three years, with annual contracts that
renew upon satisfactory progress of work. The appointee will be
working with a team of experts on randomized techniques, model
reduction, as well large- scale modeling of turbulent flows and their
HPC implementations.

The interested candidates should submit a CV, a brief (max one page)
statement of research interests, and contact information of two
references to Prof. Stephen Becker
( Questions may be directed to
Prof. Becker.

From: Armin Eftekhari
Date: August 17, 2021
Subject: Postdoc Position, Stochastic Optimization, Umea Univ

We are happy to announce a postdoctoral position in high-dimensional
stochastic optimization with application to prehospital care. The
fellowship is for two years full-time with starting date of October
15, 2021, or by agreement. The application deadline is September 16.

For more information, please visit

From: Jose Cuminato
Date: August 18, 2021
Subject: Postdoc Position, USP, Brazil

Post-Doc position in Modelling the Wheatley heart valve This project
involves the mathematical modelling of blood flow from the left
ventricle into and through a novel heart valve. The flow emerges from
the left ventricle as a spiral flow and enters the aortic valve. This
artificial valve consists of a titanium ring attached to a special
flexible polymer with a complex mathematical shape designed to rapidly
open during systole and close rapidly during diastole. It has three
leaflets which may be modelled as curved elastic membranes.

Thus the modelling problem involves fluid/structure interaction, that
may be modelled by the immersed boundary method. The fluid (blood) may
require to be treated as non-Newtonian. The candidate will need to
have expertise in computational fluid dynamics, especially in CFD
packages for simulation of fluid-structure interactions or the
immersed boundary method, a good working knowledge of fluid simulation
package(s), and a high-level programing language. The candidate will
be based in Sao Carlos, Brazil, and will be required to spend some
time at Strathclyde University, Glasgow, UK., Covid permitting. The
post is initially for one year and can be renewed for another two
depending on performance. Starting date is November 1st, 2021. To
apply, please send a CV and a reference letter to .
Applications are open until September/30st, 2021.

From: Min Hadler
Date: August 16, 2021
Subject: Postdoc Position, Univ of Vienna

We are offering a Post Doc Research Position within the
Christian-Doppler Laboratory on Mathematical Modeling and Simulations
of Next Generations of Ultrasound Devices at the Faculty of
Mathematics, University of Vienna, funded by the Christian-Doppler
Research Association ( Full time, 40 hours per
week, for an initial period of two year (with possible extensions up
to a maximum of seven years), starting on January 1st, 2022. The
researcher will work on developing and implementing inverse
reconstruction formulas for ultrasound imaging. In particular strong
interactions with the experimental partners and medical doctors at the
Medical University of Vienna are required. We anticipate that the
software components are directly implemented on programmable medical

Your profile: Strong background in mathematics and numerics of
tomography and modeling; Software implementation capabilities;
Doctorate in Mathematics, Computational Sciences, or Biomedical
Engineering or a closely related field is required; English skills

Our offer: Excellent opportunities to work in a highly motivated
research environment and collaborate with international experts in the
fields related to the project. An annual gross salary according to
the salary scheme of the Austrian Science Fund.

In case the candidate has already Postdoc experience and brings in
hardware component programming knowledge the position might even be
eligible for a senior postdoc position. Applications with personal
and scientific data and a compact statement about scientific interests
and achievements should be sent by e-mail to
till October 31st, 2021. More information can be found on

From: Raul Tempone
Date: August 19, 2021
Subject: Postdoc Positions, UQ, RWTH Aachen

The Alexander von Humboldt Chair of Mathematics for Uncertainty
Quantification (MATH4UQ) of Prof. Raul Tempone at RWTH Aachen invites
applications for several postdoctoral positions. The successful
candidates will perform mathematical and computational research and
become an active part of an international research network with a wide
scope and high visibility. The main scope of the MATH4UQ Chair is to
develop efficient numerical methods for solving forward and inverse
problems, including optimal control and optimal experimental design,
involving stochastic and random differential equations. Successful
candidates should hold a Ph.D. degree in mathematics, computer
science, computational engineering sciences, or related fields. They
should have expertise in at least one of the following areas:
uncertainty quantification, machine learning, data science, numerical
analysis, stochastic optimal control, stochastic optimization, optimal
experimental design, inverse problems as well as stochastic simulation
and approximation. The position comes with a teaching duty.

Required: Ph.D. degree in mathematics, computer science, computational
engineering sciences, or related fields, High motivation, the ability
to carry out research independently as well as to work in
interdisciplinary teams, Proficiency in written and spoken English.

Desired: Experience in performing collaborative research, Experience
teaching in German, proficiency in written and spoken German.

What we offer: Wide scope, world-class interdisciplinary scientific
research within a highly connected and motivated team.

Applications must contain a letter of motivation, a CV including a
list of publications, and copies of degree certificates, along with
contact details of at least two academic referees. Please forward
your application package to Prof. Tempone at For full consideration, please apply by
September 30, 2021. However, applications will be accepted until the
positions are filled.

From: Min Hadler
Date: August 16, 2021
Subject: Doctorate Research Position, Univ of Vienna

We are offering a Doctorate Research Position within the
Christian-Doppler Laboratory on Mathematical Modeling and Simulations
of Next Generations of Ultrasound Devices at the Faculty of
Mathematics, University of Vienna, funded by the Christian-Doppler
Research Association ( 30 working hours per
week, for an initial period of two year (with possible extensions up
to four year, or until the doctorate is finished), starting on January
1st, 2022.

The researcher will work on developing and implementing image
processing tools for ultrasound imaging. In particular strong
interactions with the experimental partners and medical doctors at the
Medical University of Vienna are required, which will evaluate the
software developments.

Your profile: Strong background in mathematics and image processing,
experience in mathematical modeling is appreciated; Software
implementation capabilities; Master in Mathematics, Computational
Sciences or a closely related field is required; English skills

Our offer: Excellent opportunities to work in a highly motivated
research environment and collaborate with international experts in the
fields related to the project; An annual gross salary according to the
salary scheme of the Austrian Science Fund.

Applications with personal and scientific data and a compact statement
about scientific interests and achievements should be sent by e-mail
to till October 31st, 2021. More information
can be found on

From: Benjamin Unger
Date: August 17, 2021
Subject: PhD Position, AI Meets Molecular Dynamics, Germany

We call for applications for a Ph.D. position working on
physics-informed machine learning with applications in molecular
dynamics. The Ph.D. thesis will be jointly supervised by two Junior
Research Group Leaders, Dr. Kristyna Pluhackova and Dr. Benjamin
Unger, at the Cluster of Excellence SimTech of the University of
Stuttgart in Germany.

Coarse-graining (CG) of molecular dynamics (MD) simulations has become
a common practice allowing scientists to describe larger simulation
systems over longer periods of time. This process is, however,
necessarily accompanied by a loss of structural information on the
stereochemistry and the relative orientation of the individual
chemical groups, making the conversion to a higher-level resolution
(also called reverse transformation or backmapping) a non-trivial
operation. Your Ph.D. task is to establish a novel AI-based
user-friendly methodology for backmapping of molecular dynamics
simulations. The goal is to speed up the procedure and avoid the
drawbacks of current state-of-the-art methodologies.

The complete call, including all application details, is posted here:

This open position is expected to be filled as soon as possible. You
are welcome to contact Dr. Kristyna Pluhackova
( and Dr. Benjamin Unger
( for further information. We
accept applications until August 31, 2021.

From: Luce le Gorrec
Date: August 16, 2021
Subject: PhD Position, Graph Partitioning, Univ of Strathclyde

Subject: Community detection is an essential tool in the analysis of

complex networks, with diverse applications such as identifying genes
related to cancer, uncovering terror cells on Twitter, and
understanding links between politicians. For the simplest case of
networks, there has been an abundant body of research, and many
effective algorithms have been designed. But for more complex
networks, the field is much more sparsely populated, due to the lack
of consensus surrounding the definition of a community. The main
focus of this PhD will be on unifying the problem of community
detection in directed networks. It will build on a recent framework
based on higher-order representations of networks, which has had some
success. It will also build on existing work by the supervisors to
produce methods tailored to the needs of the intelligence community.
The project will blend cutting edge tools for mathematical analysis
with algorithm development and extensive investigation of applications.

Full description here:

Eligibility: Applicants should have a first class or good 2.1 honours
degree (or equivalent) in a relevant discipline (mathematics, computer
science, engineering related disciplines, etc. with background in
applied mathematics and programming). Highly motivated candidates from
non- mathematical backgrounds should apply. The studentship covers
full tuition fees and a tax-free stipend for 4 years starting on the
1st of October, with an attractive Research Training Support Grant to
facilitate travel to appropriate conferences. To be eligible for a
full award a student must have no restrictions on how long they can
stay in the UK and have been ordinarily resident in the UK for at
least 3 years prior to the start of the studentship.

Deadline for application: 3rd September 2021.

Contact: To apply, please send your CV and a cover letter to Dr Phil
Knight ( or Dr Luce le Gorrec (luce.le- You can also contact us for more information

From: Ole Elvetun
Date: August 18, 2021
Subject: PhD Position, Inverse Problems, Norwegian Univ of Life Sciences

The Faculty of Science and Technology at the Norwegian University of
Life Sciences (NMBU) has a vacant PhD-position related to the project
Problem-dependent regularization techniques. The PhD position is for a
period of 3 years, or up to 4 years if teaching and other work duties
are agreed.

In the project we seek a better understanding of inverse problems when
the forward operator has a non-trivial null space, and we will analyze
the potential of applying problem-dependent regularization to inverse
problems involving EEG and ECG data.

We will furthermore investigate the properties of the technique as a
feature selection method in machine learning.

The PhD position is placed in the Norwegian government pay scale
position code 1017. PhD fellows are normally placed in pay grade 54
(NOK 491.200,-) (approx. 47.000 EUR/year) on the Norwegian Government
salary scale upon employment and follow ordinary meriting regulations.

Deadline: September 30th, 2021.

For further information and to apply, see

From: Min Hadler
Date: August 16, 2021
Subject: PhD Position, Medical Univ of Vienna

A PhD position is available at the Center for Medical Physics and
Biomedical Engineering at the Medical University of Vienna.

We offer a PhD position - within the Christian-Doppler Laboratory on
Mathematical Modeling and Simulations of Next Generations of
Ultrasound Devices, funded by the Christian-Doppler Research
Association ( in the field of ultrasound
imaging for a PhD student starting in the first quarter of 2022. Our
research will be focused on the optimisation of clinical Ultrasound
imaging systems. For this purpose the student will work with an
experimental setup for testing ultrasound scanners and will implement
optimised ultrasound sequences in close cooperation with the
department of Mathematics at the University of Vienna.

We expect from the successful candidate profound knowledge and a MSc
equivalent degree in Physics or electrical engineering preferably with
experience in experimental setups. Experience in Matlab, and/or
Python/C would strenghten the application.

Interested candidates should send a CV, a short motivation letter, and
names and e-mails of references to,
until October 31, 2021.

From: Alex Barnett
Date: August 16, 2021
Subject: Contents, Adv Comput Math (ACOM), 47 (4)

Advances in Computational Mathematics. Volume 47, Issue 4 (August
2021) is now available online at

Optimal superconvergence analysis for the Crouzeix-Raviart and the
Morley elements, Jun Hu, Limin Ma, Rui Ma

Two-scale finite element discretizations for nonlinear eigenvalue
problems in quantum physics, Pengyu Hou, Fang Liu

When is there a representer theorem? Kevin Schlegel (Open access)

Translation partitions of unity, symmetry properties, and Gabor
frames, Ole Christensen, Say Song Goh, Hong Oh Kim, Rae Young Kim

Efficient spatial second-/fourth-order finite difference ADI methods
for multi-dimensional variable-order time-fractional diffusion
equations, Hongfei Fu, Chen Zhu, Xueting Liang, Bingyin Zhang

Learning via variably scaled kernels, C. Campi, F. Marchetti,
E. Perracchione

Cayley-transform-based gradient and conjugate gradient algorithms on
Grassmann manifolds, Xiaojing Zhu, Hiroyuki Sato

Continuous window functions for NFFT, Daniel Potts, Manfred Tasche
(Open access)

Exponential mean-square stability properties of stochastic linear
multistep methods, Evelyn Buckwar, Raffaele D'Ambrosio (Open access)

Adaptive sampling and modal expansions in pattern-forming systems,
M.-L. Rapun, F. Terragni, J. M. Vega

Estimating the error in matrix function approximations, Nasim Eshghi,
Lothar Reichel

Rapid evaluation of the spectral signal detection threshold and
Stieltjes transform, William Leeb

Clothoid fitting and geometric Hermite subdivision, Ulrich Reif,
Andreas Weinmann (Open access)

From: Saul Buitrago Boret
Date: August 16, 2021
Subject: Contents, Bulletin of Computational Applied Mathematics, 8

Table of Contents
Bulletin of Computational Applied Mathematics, Vol. 8

A constrained ill-posed linear problem with data in intervals arising
in geodetic leveling, Henryk Gzyl, Silvia Mayoral

Symbolic Algorithm to Solve Initial Value Problems for Partial
Differential Equations, Srinivasarao Thota, Shiv Datt Kumar

Attractive Periodic Solutions of a Discrete Holling-Tanner
Predator-Prey Model with Impulsive Effect, Cosme Duque, Jahnett
Uzcategui, Bladismir Ruiz, Maribel Perez

Free surface flow under a gate with gravity and surface tension
effect, Abdelkader Laiadi, Abdelkrim Merzougui

Modeling of complete combustion reaction of room temperature gaseous
Alkanes via join space, Morteza Norouzi, Abolfazl Mohammadi, Violeta

End of Digest