Tidligere arrangementer - Side 52
By Anna Sturrock from the University of Essex, UK
Abstract: We investigate the simulation of a rising bubble and a stationary droplet interaction to gain a better understanding of the rising dynamics and the morphology changing of bubble-droplet aggregate. A detailed study is conducted on the interaction process under different-size bubbles with various combinations of spreading factors. The current simulation framework consists of the conservative phase-field Lattice Boltzmann equation (LBE) for interface tracking and the velocity-pressure LBE for hydrodynamics. We simulate the contact line dynamics to confirm the method's accuracy. We further investigate the morphology changing of two contact droplets under different combinations of spreading factors and depict the final morphologies in a diagram. The separated, partially engulfed and complete engulfed morphologies can be replicated by systematically altering the sign of the spreading factors. The rising bubble and droplet interaction is simulated based on different final morphologies by adding a body force. The results show that the aggregate with double emulsion morphology can avoid distortion and maintain a greater terminal velocity than the aggregate with partially engulfed morphology.
Talk is online on Zoom. Please contact "timokoch at uio.no" for the Zoom link. This talk is part of the Mechanics Lunch Seminar series. Bring-your-own-lunch and lots of questions.
Deep learning (DL) has had unprecedented success and is now entering scientific computing with full force. However, current DL methods typically suffer from instability, even when universal approximation properties guarantee the existence of stable neural networks (NNs). In this talk we will show that there are basic well-conditioned problems in scientific computing where NNs with great approximation qualities are proven to exist, however, there does not exist any algorithm, even randomised, that can train (or compute) such a NN to even 1-digit of accuracy with a probability greater than 1/2. These results provide basic foundations for Smale’s 18th problem ("What are the limits of AI?") and imply a potentially vast classification theory describing conditions under which (stable) NNs with a given accuracy can be computed by an algorithm. We begin this theory by initiating a unified theory for compressed sensing and DL, leading to sufficient conditions for the existence of algorithms that compute stable NNs in inverse problems. We introduce Fast Iterative REstarted NETworks (FIRENETs), which we prove and numerically check (via suitable stability tests) are stable. The reference for this talk is: https://arxiv.org/abs/2101.08286 (to appear in Proc. Natl. Acad. Sci. USA).
NCMM Associate Investigator, Dr. Hege G. Russnes, Group Leader of the Genomic Alterations in Cancer group at Oslo University Hospital will present her research as part of the NCMM Tuesday Seminar Series.
Avdeling for helseledelse og helse?konomi inviterer til ?pen forelesning i helseledelse.
Abstract: The fungal kingdom is one of the most species-rich organismal groups, containing up to 6 million species worldwide with a large diversity of ecosystem functions. Multicellularity has evolved independently in fungi, and over time many different growth forms and structures have originated. I will present some basics on fungal growth and the formation of complex multicellular structures.
Online participation is possible too. Please contact "timokoch at uio.no" for the Zoom link. This talk is part of the Mechanics Lunch Seminar series. Bring-your-own-lunch and lots of questions.
Tony Mroczkowski, European Southern Observatory (ESO), München.
By Rebecca Taylor from Trent University, Ontario, Canada
NCMM Associate Investigator, Dr Lorena Arranz, Group Leader of the Stem Cell Aging and Cancer Research Group will present her research as part of the NCMM Tuesday Seminar Series.
Senter for tverrfaglig kj?nnsforskning inviterer kolleger og venner til v?rt ?rlige nytt?rsselskap, som i ?r blir et digitalt arrangement. Det blir nytt?rsk?seri ved Ida Jackson og utdeling av pris for beste masteroppgave med kj?nnsperspektiv.
Super-resolution is a hot topic in current day Machine Learning. The origin of the methodology dates back to applications in seismic imaging. I discuss the evolution from the early days and highlight some papers which have given new theoretical insights along the way. I illustrate the bridge between traditional convex optimization and current day convolutional neural nets. Along the way I show some examples where we have used this for current day applications in seismic imaging.
Helene Kn?velsrud, Senior Scientist and head of the Mapping and Disrupting Cancer Circuits Project at Oslo University Hospital, and Charlotte Boccara, head of the Sleep, Cognition & Development project team at the Institute of Basic Medical Sciences, UiO, will present their latest research as part of NCMM's Tuesday Seminar series.
Thomas Montandon, Astroparticule et Cosmologie, Université Paris Diderot (France).
By Sandra Garces Pastor from UiT The Arctic University of Norway
NORHEART invites everyone with an interest in the mitochondrion and cardiovascular disease to our half-day seminar.
Models as viral assemblages? In this seminar, Marit Tolo ?stebo will look at policy models and how they come into being.
The Ports speaker series features Jatin Dua, associate professor of anthropology at the University of Michigan.
Martin Burkert, NCMM Postdoctoral Fellow from the group of Sebastian Waszak, will present his research as part of the NCMM Tuesday Seminar series.
By Micah Dunthorn from the Natural History Museum, University of Oslo
Abstract: Transport and mixing in multiphase flow through porous media plays a key role in a range of biological, geological, and engineered systems. Here, we use numerical simulations to investigate the effect of intermittent multiphase flow on fluid stretching and folding, a fundamental mechanism driving solute mixing and reaction in porous media. We show that, in contrast to steady single-phase flows, the concurrent flow of two immiscible phases induces chaotic mixing, characterized by exponential stretching in the pore space. The stretching rate is found to decay with increasing capillary number, implying that the increasing flow intermittency observed at lower capillary numbers enhances the mixing efficiency. We propose a mechanistic model to link the basic multiphase flow properties to the chaotic mixing rate, opening new perspectives to understand mixing and reaction in multiphase porous media flows. The results presented here form part of the background for the recently started RCN-funded project M4: Mixing in Multiphase flow through Microporous Media, which will also be introduced.
This talk is part of the Mechanics Lunch Seminar series. Bring-your-own-lunch and lots of questions.
The Belt and Road Initiative (BRI) is one of China’s most discussed foreign policy initiatives. What is the BRI? How does it influence other countries? In this webinar, Freymann will give a presentation of his book and answer questions from the audience, in discussion with ?zge S?ylemez.
NCMM Associate Investigator Emre Yaksi, Professor at the Kavli Institute for Systems Neuroscience, NTNU will present his research as part of NCMM's Tuesday seminar series.