pinecone/core-2020-05-10-deduplication huggingface dataset:
Radial Migration in Spiral Galaxies

The redistribution of stars in galactic disks is an important aspect of disk
galaxy evolution. Stars that efficiently migrate in such a way that does not
also appreciably heat their orbits can drastically affect the stellar
populations observed today and therefore influence constraints derived from
such observations. Unfortunately, while the theoretical understanding of the
migration process is becoming increasingly robust, there are currently few
specific observable predictions. As a result, we do not yet have a clear handle
on whether the process has been important for the Milky Way in the past or how
to constrain it. I discuss some of the expected qualitative outcomes of
migration as well as some current controversies.Comment: To appear in "Lessons from the Local Group - A Conference in honor of
  David Block and Bruce Elmegreen" eds. Freeman, K.C., Elmegreen, B.G., Block,
  D.L., and Woolway,
Manifestations of the Galactic Center Magnetic Field

Several independent lines of evidence reveal that a relatively strong and
highly ordered magnetic field is present throughout the Galaxy's central
molecular zone (CMZ). The field within dense clouds of the central molecular
zone is predominantly parallel to the Galactic plane, probably as a result of
the strong tidal shear in that region. A second magnetic field system is
present outside of clouds, manifested primarily by a population of vertical,
synchrotron-emitting filamentary features aligned with the field. Whether or
not the strong vertical field is uniform throughout the CMZ remains
undetermined, but is a key central issue for the overall energetics and the
impact of the field on the Galactic center arena. The interactions between the
two field systems are considered, as they are likely to drive some of the
activity within the CMZ. As a proxy for other gas-rich galaxies in the local
group and beyond, the Galactic center region reveals that magnetic fields are
likely to be an important diagnostic, if not also a collimator, of the flow of
winds and energetic particles out of the nucleus.Comment: To appear in "LESSONS FROM THE LOCAL GROUP" - A Conference in Honour
  of David Block and Bruce Elmegreen, eds: Freeman, K.C., Elmegreen, B.G.,
  Block, D.L. & Woolway, M. (SPRINGER: NEW YORK
Cosmic evolution of gas content and accretion

In the present universe, the gas is a minor component of giant galaxies, and
its dominant phase is atomic (HI). During galaxy evolution in cosmic times,
models predict that gas fractions were much higher in galaxies, and gas phases
could be more balanced between molecular (H2) and atomic (HI). This gaseous
evolution is certainly a key factor to explain the cosmic evolution of the star
formation rate density. Star formation efficiency might also vary with
redshift, and the relative importance of these factors is not yet well known.
Our current knowledge of cosmic evolution of gas from molecular observations at
high-z is reviewed and confronted to simulations.Comment: 8 pages, 3 figures, to be published in Seychelles conference on
  galaxy evolution, "Lessons from the Local Group", ed. K. C. Freeman, B. G.
  Elmegreen, D. L. Block, and M. Woolway (Dordrecht: Springer), in press, 201
Lyman alpha emitting and related star-forming galaxies at high redshift

I provide an overview about star-forming galaxies at high redshift and their
physical properties. Starting from the populations of Ly-$\alpha$ emitters and
Lyman break galaxies, I summarize their common features and distinction. Then I
summarize recent insight onto their physical properties gained from SED models
including nebular emission, and various implications from these studies on the
properties of star-formation at high redshift. Finally, I present new results
and an overview on the dust content and UV attenuation of $z>6$ galaxies
obtained from IRAM and ALMA observations.Comment: 12 pages, 5 figures. To appear in "LESSONS FROM THE LOCAL GROUP - A
  Conference in Honour of David Block and Bruce Elmegreen", eds. Freeman, K.C.,
  Elmegreen, B.G., Block, D.L. & Woolway, M. (SPRINGER: NEW YORK
Dust in the Local Group

How dust absorbs and scatters starlight as a function of wavelength (known as
the interstellar extinction curve) is crucial for correcting for the effects of
dust extinction in inferring the true luminosity and colors of reddened
astrophysical objects. Together with the extinction spectral features, the
extinction curve contains important information about the dust size
distribution and composition. This review summarizes our current knowledge of
the dust extinction of the Milky Way, three Local Group galaxies (i.e., the
Small and Large Magellanic Clouds, and M31), and galaxies beyond the Local
Group.Comment: 21 pages, 11 figures; invited review article published in "LESSONS
  FROM THE LOCAL GROUP -- A Conference in Honour of David Block and Bruce
  Elmegreen" eds. Freeman, K.C., Elmegreen, B.G., Block, D.L. & Woolway, M.
  (SPRINGER: NEW YORK), pp. 85-10
Local stability conditions and calibrating procedure for new
  car-following models used in driving simulators

The Intelligent Driver Model is studied and several drawbacks with respect to
driving simulators are defined. We present two modifications of the IDM. The
first one gives any predefined distance to the leading vehicle in a steady
state. The second modification is a combination of the first one and the
optimal velocity model. It takes into account drivers reaction time explicitly
and is described by delay differential equation. This model always results in
realistic vehicles accelerations what allows simulating real traffic
collisions. Necessary and sufficient conditions are obtained, that guarantee a
non-oscillating solution near the equilibrium for the vehicle platoon. We
suggest the calibrating framework based on a numerical solution of the
constrained optimization problem. Nonlinear constraints are generated by the
numerical integration scheme. The suggested procedure incorporates the local
stability conditions obtained and takes into account vehicle dynamics, drivers
behavior and weather conditions.Comment: 9 pages, 4 figures, contribution to the conference Traffic and
  Granular Flow '13 in Juelich. It is included in the Conference proceedings
  (Springer
Modeling of pedestrians

Different families of models first developed for fluid mechanics have been
extended to road, pedestrian, or intracellular transport. These models allow to
describe the systems at different scales and to account for different aspects
of dynamics. In this paper, we focus on pedestrians and illustrate the various
families of models by giving an example of each type. We discuss the
specificities of crowds compared to other transport systems.Comment: 10 pages Proceedings of the conference "Traffic and Granular Flow
  '13" held in Julich, Germany (25 - 27 September 2013
Experimental Analysis of Two-Dimensional Pedestrian Flow in front of the
  Bottleneck

This contribution presents experimental study of two-dimensional pedestrian
flow with the aim to capture the pedestrian behaviour within the cluster formed
in front of the bottleneck. Two experiments of passing through a room with one
entrance and one exit were arranged according to phase transition study in
Ezaki et al. (2012), the inflow rate was regulated to obtain different walking
modes. By means of automatic image processing, pedestrians' paths are extracted
from camera records to get actual velocity and local density. Macroscopic
information is extracted by means of virtual detector and leaving times of
pedestrians. The pedestrian's behaviour is evaluated by means of density and
velocity. Different approaches of measurement are compared using several
fundamental diagrams. Two phases of crowd behaviour have been recognized and
the phase transition was described.Comment: In proceedings of Traffic and Granullar Flow 2013, Springe
From Drivers to Athletes -- Modeling and Simulating Cross-Country Sking
  Marathons

Traffic flow of athletes in classic-style cross-country ski marathons, with
the Swedish Vasaloppet as prominent example, represents a non-vehicular system
of driven particles with many properties of vehicular traffic flow such as
unidirectional movement, the existence of lanes, and, moreover, severe traffic
jams. We propose a microscopic acceleration and track-changing model taking
into account different fitness levels, gradients, and interactions between the
athletes in all traffic situations. The model is calibrated on microscopic data
of the $\textit{Vasaloppet 2012}$ Using the multi-model open-source simulator
MovSim.org, we simulate all 15 000 participants of the Vasaloppet during the
first ten kilometers.Comment: 8 pages, contribution to the conference Traffic and Granular Flow '13
  in Juelich. Will be included in the Conference proceedings (Springer
Crowd Flow Modeling of Athletes in Mass Sports Events -- a Macroscopic
  Approach

We propose a macroscopic model in form of a dispersion-transport equation for
non-congested flow of the athletes which is coupled to a kinematic-wave model
for congested flow. The model takes into account the performance (i.e.,
free-flow speed distributions) of the athletes in the different starting
groups. The model is calibrated and validated on data of the German
$\textit{Rennsteig Half Marathon 2012}$ and the Swedish $\textit{Vasaloppet
2012}$ cross-country ski race. Simulations of the model allow the event
managers to improve the organization by determining the optimum number of
starting groups, the maximum size of each group, whether a wave start with a
certain starting delay between the groups is necessary, or what will be the
effects of changing the course. We apply the model to simulate a planned course
change for the Rennsteig Half Marathon 2013, and determine whether critical
congestions are likely to occur.Comment: Presented at the Conference Traffic and Graranular Flow '13
  (Juelich). Will appear in the proceedings (Springer
Statistical Analysis of High-Flow Traffic States

The relation between the fundamental observables of traffic flow (i.e.,
vehicle density, flow rate, and average velocity) is of great importance for
the study of traffic phenomena. Probably the most common source of such data
are inductive loop detectors, which count the number of passing vehicles and
measure their speed. We will present an analysis of detector data collected by
more than 3000 loop detectors during the past three years on the motorway
network of the state of North Rhine-Westphalia. Besides presenting some general
aspects of traffic flow, our analysis focuses on the characteristics of
so-called high-flow states, i.e. traffic states where the flow rate exceeds 50
vehicles per minute and lane (3000 veh/h/lane). We investigate the duration,
frequency and other statistics of such states, the viability of the data and we
study the conditions under which they occur. The factors that influence the
existence of high-flow states in traffic are, for instance, the fraction of
slow vehicles (namely trucks), the motorway's general topology (e.g. number of
lanes), the hour of the day and day of the week. This information is directly
accessible from the detector data.Comment: 6 pages, 4 figures, presented at "Traffic and Granular Flow 2013"
  conferenc
Stochastic modeling of cargo transport by teams of molecular motors

Many different types of cellular cargos are transported bidirectionally along
microtubules by teams of molecular motors. The motion of this cargo-motors
system has been experimentally characterized in vivo as processive with rather
persistent directionality. Different theoretical approaches have been suggested
in order to explore the origin of this kind of motion. An effective theoretical
approach, introduced by M\"uller et al., describes the cargo dynamics as a
tug-of-war between different kinds of motors. An alternative approach has been
suggested recently by Kunwar et al., who considered the coupling between motor
and cargo in more detail. Based on this framework we introduce a model
considering single motor positions which we propagate in continuous time.
Furthermore, we analyze the possible influence of the discrete time update
schemes used in previous publications on the system's dynamic.Comment: Cenference proceedings - Traffic and Granular Flow 1
Compositionality Results for Quantitative Information Flow

International audienceIn the min-entropy approach to quantitative information ﬂow, the leakage is deﬁned in terms of a minimization problem, which, in case of large systems, can be computationally rather heavy. The same happens for the recently proposed generalization called g-vulnerability. In this paper we study the case in which the channel associated to the system can be decomposed into simpler channels, which typically happens when the observables consist of several components. Our main contribution is the derivation of bounds on the g-leakage of the whole system in terms of the g-leakage of its components
Deciding the Value 1 Problem for Reachability in 1-Clock Decision Stochastic Timed Automata

International audienceWe consider reachability objectives on an extension of stochastic timed automata (STA) with nondeterminism. Decision stochastic timed automata (DSTA) are Markov decision processes based on timed automata where delays are chosen randomly and choices between enabled edges are nondeterministic. Given a reachability objective, the value 1 problem asks whether a target can be reached with probability arbitrary close to 1. Simple examples show that the value can be 1 and yet no strategy ensures reaching the target with probability 1. In this paper, we prove that, the value 1 problem is decidable for single clock DSTA by non-trivial reduction to a simple almost-sure reachability problem on a finite Markov decision process. The ε-optimal strategies are involved: the precise probability distributions, even if they do not change the winning nature of a state, impact the timings at which ε-optimal strategies must change their decisions, and more surprisingly these timings cannot be chosen uniformly over the set of regions
Formal Analysis of a Fault-Tolerant Routing Algorithm for a Network-on-Chip

International audienceA fault-tolerant routing algorithm in Network-on-Chip architectures provides adaptivity for on-chip communications. Adding fault-tolerance adaptivity to a routing algorithm increases its design complexity and makes it prone to deadlock and other problems if improperly implemented. Formal verification techniques are needed to check the correctness of the design. This paper performs formal analysis on an extension of the link-fault tolerant Network-on-Chip architecture introduced by Wu et al. that supports multiflit wormhole routing. This paper describes several lessons learned during the process of constructing a formal model of this routing architecture. Finally, this paper presents how the deadlock freedom and tolerance to a single-link fault is verified for a two-by-two mesh version of this routing architecture
Convergence of Parareal for the Navier-Stokes Equations Depending on the Reynolds Number

The paper presents first a linear stability analysis for the time-parallel Parareal method, using an IMEX Euler as coarse and a Runge-Kutta-3 method as fine propagator, confirming that dominant imaginary eigenvalues negatively affect Parareal’s convergence. This suggests that when Parareal is applied to the nonlinear Navier-Stokes equations, problems for small viscosities could arise. Numerical results for a driven cavity benchmark are presented, confirming that Parareal’s convergence can indeed deteriorate as viscosity decreases and the flow becomes increasingly dominated by convection. The effect is found to strongly depend on the spatial resolution
One-site density matrix renormalization group and alternating minimum
  energy algorithm

Given in the title are two algorithms to compute the extreme eigenstate of a
high-dimensional Hermitian matrix using the tensor train (TT) / matrix product
states (MPS) representation. Both methods empower the traditional alternating
direction scheme with the auxiliary (e.g. gradient) information, which
substantially improves the convergence in many difficult cases. Being
conceptually close, these methods have different derivation, implementation,
theoretical and practical properties. We emphasize the differences, and
reproduce the numerical example to compare the performance of two algorithms.Comment: Submitted to the proceedings of ENUMATH 201
Unveiling WARIS Code, a Parallel and Multi-purpose FDM Framework

WARIS is an in-house multi-purpose framework focused on solving scientific problems using Finite Difference Methods as numerical scheme. Its framework was designed from scratch to solve in a parallel and efficient way Earth Science and Computational Fluid Dynamic problems on a wide variety of architectures.\ud
WARIS uses structured meshes to discretize the problem domains, as these are better suited for optimization in accelerator-based architectures. To succeed in such challenge, WARIS framework was initially designed to be modular in order to ease development cycles, portability, reusability and future extensions of the framework. In order to assess its performance, a code that solves the vectorial Advection-Diffusion-Sedimentation equation has been ported to the WARIS framework. This problem appears in many geophysical applications, including atmospheric transport of passive substances. As an application example, we focus on atmospheric dispersion of volcanic ash, a case in which operational code performance is critical given the threat posed by this substance on aircraft engines. Preliminary results\ud
are very promising, performance has been improved by 8.2× with respect to the baseline code using a realistic case. This opens new perspectives for operational setups, including efficient ensemble forecast.Peer ReviewedPostprint (author's final draft)The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-319-10705-9_5
Convergence of Parareal for the Navier-Stokes equations depending on the
  Reynolds number

The paper presents first a linear stability analysis for the time-parallel
Parareal method, using an IMEX Euler as coarse and a Runge-Kutta-3 method as
fine propagator, confirming that dominant imaginary eigenvalues negatively
affect Parareal's convergence. This suggests that when Parareal is applied to
the nonlinear Navier-Stokes equations, problems for small viscosities could
arise. Numerical results for a driven cavity benchmark are presented,
confirming that Parareal's convergence can indeed deteriorate as viscosity
decreases and the flow becomes increasingly dominated by convection. The effect
is found to strongly depend on the spatial resolution
Novelty Search in Competitive Coevolution

One of the main motivations for the use of competitive coevolution systems is
their ability to capitalise on arms races between competing species to evolve
increasingly sophisticated solutions. Such arms races can, however, be hard to
sustain, and it has been shown that the competing species often converge
prematurely to certain classes of behaviours. In this paper, we investigate if
and how novelty search, an evolutionary technique driven by behavioural
novelty, can overcome convergence in coevolution. We propose three methods for
applying novelty search to coevolutionary systems with two species: (i) score
both populations according to behavioural novelty; (ii) score one population
according to novelty, and the other according to fitness; and (iii) score both
populations with a combination of novelty and fitness. We evaluate the methods
in a predator-prey pursuit task. Our results show that novelty-based approaches
can evolve a significantly more diverse set of solutions, when compared to
traditional fitness-based coevolution.Comment: To appear in 13th International Conference on Parallel Problem
  Solving from Nature (PPSN 2014
On the Effectiveness of Sampling for Evolutionary Optimization in Noisy Environments

Sampling has been often employed by evolutionary algorithms to cope with noise when solving noisy real-world optimization problems. It can improve the estimation accuracy by averaging over a number of samples, while also increasing the computation cost. Many studies focused on designing efficient sampling methods, and conflicting empirical results have been reported. In this paper, we investigate the effectiveness of sampling in terms of rigorous running time, and find that sampling can be ineffective. We provide a general sufficient condition under which sampling is useless (i.e., sampling increases the running time for finding an optimal solution), and apply it to analyzing the running time performance of (1+1)-EA for optimizing OneMax and Trap problems in the presence of additive Gaussian noise. Our theoretical analysis indicates that sampling in the above examples is not helpful, which is further confirmed by empirical simulation results
Combined Failure Mechanism of a Breakwater Subject to Tsunami during 2011 East Japan Earthquake

<Book Title>Perspectives on Earthquake Geotechnical EngineeringIn this study, a centrifuge model tests and effective stress analyses are performed on a breakwater subject to Tsunami such as those seriously damaged during 2011 East Japan Earthquake (Magnitude 9.0). The centrifuge model tests at a scale of 1/200 are performed to simulate the failure of a breakwater subject to Tsunami. With the effective stress analyses, this study demonstrates the importance of the mechanism of failure in the rubble mound due to seepage flow of pore water in addition to the force of Tsunami action
Effects of graph embellishments on the perception of system states in mobile monitoring tasks

Monitoring of critical systems such as large server parks require suitable visualization tools that draw the attention to essential aspects of system state to ensure continuous operation. Moreover, administration is increasingly performed using mobile devices giving operators more freedom. Mobile device form factors limit the amount of data that can be displayed. This study explores if visual embellishments in data visualizations improve the perception of system states for mobile administrators. The RRDtool time series data visualizer, which is deployed by the Munin monitoring tool, is used as basis and compared to an experimental monitoring tool that employs visual embellishment enhancements. Talk aloud system monitoring sessions were employed with 24 IT-professionals both with and without Munin experience. The results show that the embellishments results in significantly shorter time to interpret the views while they do not significantly help determine the general characteristics of the views. Previous experience with Munin had limited effect on performance. One implications of this work is that embellishments can help focus attention towards important state changes in mobile visualization
Automatic validation of flowmeter data in transport water networks: Application to the ATLLc water network

In this paper, a methodology for data validation and reconstruction of flow meter sensor data in water networks is presented. The raw data validation is inspired on the Spanish norm (AENOR-UNE norm 500540). The methodology consists in assigning a quality level to data. These quality levels are assigned according to the number of tests that data have passed. The methodology takes into account not only spatial models but also temporal models relating the different sensors. The methodology is applied to real-data acquired from the ATLLc Water Network. The results demonstrate the performance of the proposed methodology in detecting errors in measurements and in reconstructing them.Peer ReviewedPostprint (author’s final draft