Publications associées à Arborescence

Magnetic structure of the two-dimensional XY antiferromagnet Sr2CoSi2O7 studied using single-crystal neutron diffraction

We report a combined polarized and unpolarized neutron diffraction study on a multiferroic Sr2CoSi2O7 (SCSO) single crystal below and above the antiferromagnetic ordering temperature TN = 6.5 K. Unpolarized neutron diffraction measurements at 15 K confirm ...

AMER PHYSICAL SOC2023

From Trees to Barcodes and Back Again: A Combinatorial, Probabilistic and Geometric Study of a Topological Inverse Problem

Adélie Eliane Garin

In this thesis, we investigate the inverse problem of trees and barcodes from a combinatorial, geometric, probabilistic and statistical point of view. Computing the persistent homology of a merge tree yields a barcode B. Reconstructing a tree from B invol ...

EPFL2022

From vesicles to materials: bioinspired strategies for fabricating hierarchically structured soft matter

Esther Amstad

Certain organisms including species of mollusks, polychaetes, onychophorans and arthropods produce exceptional polymeric materials outside their bodies under ambient conditions using concentrated fluid protein precursors. While much is understood about the ...

ROYAL SOC2021

Incommensurate crystal structure of PbHfO3

Alla Arakcheeva

Controversy in the description/identification of so-called intermediate phase(s) in PbHfO3, stable in the range similar to 420-480 K, has existed for a few decades. A synchrotron diffraction experiment on a partially detwinned crystal allowed the structure ...

INT UNION CRYSTALLOGRAPHY2020

The Jazz Harmony Treebank

Martin Alois Rohrmeier, Daniel Harasim, Christoph Finkensiep, Petter Harald Ericson

Grammatical models which represent the hierarchical structure of chord sequences have proven very useful in recent analyses of Jazz harmony. A critical resource for building and evaluating such models is a ground-truth database of syntax trees that encode ...

ISMIR2020

Asymptotically Optimal Contextual Bandit Algorithm Using Hierarchical Structures

Hakan Gökcesu, Kaan Gökcesu

We propose an online algorithm for sequential learning in the contextual multiarmed bandit setting. Our approach is to partition the context space and, then, optimally combine all of the possible mappings between the partition regions and the set of bandit ...

2019

Improving Spatial Data Processing by Clipping Minimum Bounding Boxes

Anastasia Ailamaki, Darius Sidlauskas, Eleni Tzirita Zacharatou

The majority of spatial processing techniques rely heavily on the idea of approximating each group of spatial objects by their minimum bounding box (MBB). As each MBB is compact to store (requiring only two multi-dimensional points) and intersection tests ...

IEEE2018

ScienceWISE: Topic Modeling over Scientific Literature Networks

Paolo De Los Rios, Alessio Vincenzo Cardillo, Andrea Martini

We provide an up-to-date view on the knowledge management system ScienceWISE (SW) and address issues related to the automatic assignment of articles to research topics. So far, SW has been proven to be an effective platform for managing large volumes of te ...

2017

Automated Reconstruction of Evolving Curvilinear Tree Structures

Przemyslaw Rafal Glowacki

Curvilinear networks are prevalent in nature and span many different scales, ranging from micron-scale neural structures in the brain to petameter-scale dark-matter arbors binding massive galaxy clusters. Reliably reconstructing them in an automated fashio ...

EPFL2016

Micro- and nanoscale hierarchical structure of core-shell protein microgels

Giovanni Dietler, Francesco Simone Ruggeri, Raffaele Mezzenga

Protein nanofibrils were first discovered in the context of misfolding and neurodegenerative diseases but have recently been found in naturally occurring functional materials including algal adhesives, bacterial coatings, and even mammalian melanosomes. Th ...

Royal Society of Chemistry2016

Scaling Similarity Joins over Tree-Structured Data

Given a large collection of tree-structured objects (e.g., XML documents), the similarity join finds the pairs of objects that are similar to each other, based on a similarity threshold and a tree edit distance measure. The state-of-the-art similarity join ...

Assoc Computing Machinery2015

RRB Vector: A Practical General Purpose Immutable Sequence

Martin Odersky, Tiark Rompf, Nicolas Alexander Stucki, Vlad Ureche

State-of-the-art immutable collections have wildly differing performance characteristics across their operations, often forcing programmers to choose different collection implementations for each task. Thus, changes to the program can invalidate the choice ...

ACM2015

RUBIK: Efficient Threshold Queries on Massive Time Series

Anastasia Ailamaki, Thomas Heinis, Farhan Tauheed, Eleni Tzirita Zacharatou

An increasing number of applications from finance, meteorology, science and others are producing time series as output. The analysis of the vast amount of time series is key to understand the phenomena studied, particularly in the simulation sciences, wher ...

2015

Distributed Rate Allocation in Inter-Session Network Coding

Pascal Frossard, Nikolaos Thomos, Eirina Bourtsoulatze

In this work, we propose a distributed rate allocation algorithm that minimizes the average decoding delay for multimedia clients in inter-session network coding systems. We consider a scenario where the users are organized in a mesh network and each user ...

Institute of Electrical and Electronics Engineers2014

Dendritic tree extraction from noisy maximum intensity projection images in C-elegans

Pascal Fua, Raphael Sznitman, Josué Sznitman

Background: Maximum Intensity Projections (MIP) of neuronal dendritic trees obtained from confocal microscopy are frequently used to study the relationship between tree morphology and mechanosensory function in the model organism C. elegans. Extracting den ...

Biomed Central Ltd2014

Vortex lattice structure in BaFe2(As0.67P0.33)(2) via small-angle neutron scattering

Jonathan White

We have observed a magnetic vortex lattice (VL) in BaFe2(As0.67P0.33)(2) (BFAP) single crystals by small-angle neutron scattering. With the field along the c axis, a nearly isotropic hexagonal VL was formed in the field range from 1 to 16 T, and no symmetr ...

Amer Physical Soc2014

Scalable and Dynamically Balanced Shared-Everything OLTP with Physiological Partitioning

Anastasia Ailamaki, Frederick Ryan Johnson, Pinar Tözün, Ippokratis Pandis

Scaling the performance of shared-everything transaction processing systems to highly-parallel multicore hardware remains a challenge for database system designers. Recent proposals alleviate locking and logging bottlenecks in the system, leaving page latc ...

2013

Model-View Sensor Data Management in the Cloud

Karl Aberer, Tian Guo

Infinite nature of sensor data poses a serious challenge for query processing even in a cloud infrastructure. Model-based sensor data approximation reduces the amount of data for query processing, but all modeled segments need to be scanned, in the worst c ...

2013

Model-View Sensor Data Management in the Cloud

Karl Aberer, Tian Guo

Infinite nature of sensor data poses a serious challenge for query processing even in a cloud infrastructure. Model-based sensor data approximation reduces the amount of data for query processing, but all modeled segments need to be scanned, in the worst c ...

IEEE2013

Automated Reconstruction of Curvilinear Networks from 2D and 3D Imagery

Engin Türetken

Reconstructing complex curvilinear structures such as neural circuits, road networks, and blood vessels is a key challenge in many scientific and engineering fields. It has a broad range of applications, from the delineation of micrometer-sized neurons in ...

EPFL2013