bluuebunny/crossref_metadata_2025_split huggingface dataset:
A stochastic ADMM algorithm for large-scale ptychography with weighted difference of anisotropic and isotropic total variation
Authors: Bui Kevin , Di Zichao (Wendy) 
Published: February 2024

Abstract
Ptychography, a prevalent imaging technique in fields such as biology and optics, poses substantial challenges in its reconstruction process, characterized by nonconvexity and large-scale requirements. This paper presents a novel approach by introducing a class of variational models that incorporate the weighted difference of anisotropic–isotropic total variation. This formulation enables the handling of measurements corrupted by Gaussian or Poisson noise, effectively addressing the nonconvex challenge. To tackle the large-scale nature of the problem, we propose an efficient stochastic alternating direction method of multipliers, which guarantees convergence under mild conditions. Numerical experiments validate the superiority of our approach by demonstrating its capability to successfully reconstruct complex-valued images, especially in recovering the phase components even in the presence of highly corrupted measurements.
Characterization of real-time cine MR imaging distortion on 0.35 T MRgRT with concentric cine imaging QA phantom
Authors: Marasini Shanti , Cole Mike , Curcuru Austen , Dyke Lara M , Gach H Michael , Flores Rocco , Kim Taeho 
Published: February 2024

Abstract

Objective. Real-time MRgRT uses 2D-cine imaging for target tracking and motion evaluation. Rotation of gantry induced B
0 off-resonance, resulting in image artifacts and imaging isocenter-shift precluding MR-guided arc therapy. Standard MRI phantoms designed for higher resolution images face challenges when low-resolution cine imaging is needed to achieve high frame rates. This work aimed to examine the spatial accuracy including geometric distortion and isocenter shift in real-time during gantry rotation on a 0.35 T MR-Linac using the concentric Cine imaging quality assurance (QA) phantom and its associated image analysis software. Approach. The Cine imaging QA phantom consists of two concentric shells of low-T1 mineral oil and a central alignment structure. The phantom was scanned on three different MRI systems; 0.55 T Siemens Free.Max, 1.5 T Philips Ingenia, and 0.35 T ViewRay MRIdian MR-Linac using 2D balanced steady-state free precession (bSSFP) imaging sequence. In addition, bSSFP cine MRI with the banding artifact correction was tested on 0.35 T ViewRay MR-Linac. Images from the MR-Linac were acquired with the Linac gantry stationary and rotating from gantry 300°→ 0° and vice versa. Three orthogonal image planes were scanned excluding the 1.5 T Philips Ingenia, where only the axial plane was scanned. The image analysis software calculated the distortion values as well as the isocenter position for each cine frame. Main results. The geometric distortion of cine imaging on MRIs and MR-Linac at gantry stationary are within 1 mm while the substantial geometric distortion of 2 and 2.2 mm were observed on 0.35 T MR-Linac while rotating the gantry clockwise (300°→ 0°) and counterclockwise 0°→ 300° respectively. The average imaging isocenter shift was 0.1 mm for both MRIs and the static gantry and imaging isocenter shift of ≤1.5 mm was observed during the gantry rotation. The imaging isocenter shift decreased by 1 ± 0.2 mm clockwise and counterclockwise with B
0 compensation. Significance. The concentric Cine imaging QA phantom and its associated software effectively demonstrate the image distortion on real-time cine imaging on regular MRIs and 0.35 T MR-Linac. The results of significant geometric distortion with a rotating gantry in the MR-Linac system require further investigation to alleviate the extent of the image distortion.
Low scale leptogenesis in singlet-triplet scotogenic model
Authors: Singh Labh , Mahanta Devabrat , Verma Surender 
Published: February 2024

Abstract
The scotogenic model presents an elegant and succinct framework for elucidating the origin of tiny neutrino masses within the framework of the Standard Model, employing radiative corrections within the domain of the dark sector. We investigate the possibility of achieving low-scale leptogenesis in the singlet-triplet scotogenic model (STSM), where dark matter mediates neutrino mass generation. We initially considered a scenario involving two moderately hierarchical heavy fermions, N and Σ, wherein the lepton asymmetry is generated by the out-of-equilibrium decay of both particles. Our analysis indicates that the scale of leptogenesis in this scenario is similar to that of standard thermal leptogenesis and is approximately M

N,Σ ∼ 109 GeV, which is comparable to the Type-I seesaw case. Further, we consider the case with three heavy fermions (N
2, N
2, and Σ) with the hierarchy M

N
1
< M
Σ ≪ MM
N
2
, which yields the lower bound on heavy fermions up to 3.1 TeV, therefore significantly reduce the scale of the leptogenesis up to TeV scale. The only prerequisite is suppression in the N
1 and Σ Yukawa couplings, which causes suppressed washout effects and a small active neutrino mass of about 10-5 eV. This brings about the fascinating insight that experiments aiming to measure the absolute neutrino mass scale can test low-scale leptogenesis in the scotogenic model. Further, the hyperchargeless scalar triplet Ω provides an additional contribution to mass of the W-boson explaining CDF-II result.
Early dark energy constraints with late-time expansion marginalization
Authors: Rebouças João , Gordon Jonathan , de Souza Diogo H.F. , Zhong Kunhao , Miranda Vivian , Rosenfeld Rogerio , Eifler Tim , Krause Elisabeth 
Published: February 2024

Abstract
Early dark energy (EDE) is an extension to the ΛCDM model that includes an
additional energy density contribution near recombination. The model was proposed to reduce the
tension between the measurements of the Hubble constant H
0 from the cosmic microwave background (CMB) and from the local cosmic distance ladder. Some analyses in the recent literature have
shown intriguing hints for EDE. However, this model increases the tension in the derived
clustering of galaxies (as measured by the so-called S
8 parameter) between CMB and large scale
structure (LSS) measurements. This new tension limits the contribution of EDE during
recombination, and thus its effect on the Hubble tension. In this work, we investigate whether
the inclusion of a general, smooth late-time dark energy modification can increase back the EDE
contribution when LSS data is included in the analysis. In order to generalize the late expansion
with respect to the ΛCDM model, we substitute the cosmological constant by a late dark
energy fluid model with a piecewise constant equation of state w(z) in redshift bins. We show
that, when analysing this generalized model with combinations of CMB, LSS and type Ia supernovae
data from several experiments no significant changes on S
8 and EDE parameter constraints is
found. The contribution to the EDE fraction constraint with late-time expansion marginalization is f
EDE = 0.067+0.019
-0.027 using 3 redshift bins, with similar results for 5 and
10 redshift bins. This work shows that in order to solve simultaneously the Hubble and S
8
tensions, one needs a mechanism for increasing the clustering of matter at late times different
from a simple change in the background evolution of late dark energy.
ULDM self-interactions, tidal effects and tunnelling out of satellite galaxies
Authors: Dave Bihag , Goswami Gaurav 
Published: February 2024

Abstract
It is well-known that Dark Matter (DM) inside a satellite galaxy orbiting a host halo experiences a tidal potential. If DM is ultra-light, given its wave-like nature, one expects it to tunnel out of the satellite — if this happens sufficiently quickly, then the satellite will not survive over cosmological timescales, severely constraining this dark matter model.
In this paper, we study the effects of the inevitable quartic self-interaction of scalar Ultra-Light Dark Matter (ULDM) on the lifetimes of satellite galaxies by looking for quasi-stationary solutions with outgoing wave boundary conditions.
For a satellite with some known core mass and orbital period, we find that, attractive (repulsive) self-interactions decrease (increase) the rate of tunnelling of DM out of it.
In particular, for satellite galaxies with core mass ∼𝒪(107–108) M⊙ and orbital period ∼𝒪(1) Gyr, one can impose constraints on the strength of self-interactions as small as λ∼𝒪(10-92). For instance, for ULDM mass m = 10-22 eV, the existence of the Fornax dwarf galaxy necessitates attractive self-interactions with λ≲ -2.12 × 10-91.
An AstroSat/UVIT study of galaxies in the cluster Abell 2199
Authors: Mahajan Smriti , Singh Kulinder Pal , Raychaudhury Somak 
Published: February 2024

Abstract
We present the newly acquired data for an AstroSat/UVIT field centred on a face-on spiral starburst galaxy UGC 10420, located in the X-ray bright cluster Abell 2199 (z = 0.031).
We have analysed the FUV BaF2 data for this field along with the archival FUV and NUV data from the GALEX mission, optical photometric data from the SDSS, spectroscopic data
from the literature,
and low-frequency radio data from the LoTSS survey, respectively. The stars were separated from the galaxies using the SDSS photometric pipeline classification, while the spectroscopic
redshifts available for 35% of the detected UVIT sources were used to identify member galaxies of the cluster Abell 2199. We find that (a) the non-cluster galaxies are on average fainter than the
cluster galaxies at fixed magnitude, (b) stars and galaxies are indistinguishable in the r vs. NUV–r plane, and (c) bright stars are ∼
1.5 mag bluer than the galaxies in the FUV–r vs. NUV–r colour-colour plane. Besides UGC 10420 which is the only known cluster galaxy with an extended-UV disk, we identify five more galaxies with asymmetric FUV
morphology and extended radio emission in this field. All the asymmetric member galaxies of Abell 2199, lie within the virial boundaries of the cluster.
This observation, together with the fact that these asymmetric cluster galaxies have low-frequency radio tails or FUV emission pointing away from the cluster centre leads us to hypothesise that
these galaxies are likely undergoing ram-pressure stripping (RPS) under the influence of cluster-environment related mechanisms. A comparison of optical and FUV star formation
rate of UVIT detected galaxies shows enhanced star formation in half of the RPS candidates, suggesting that environment-related mechanisms may lead to a burst of star formation
in RPS galaxies.
Our analysis indicates the presence of at least two more groups or clusters at z ∼ 0.077 and 0.260, coincident with Abell 2199 along the line of sight of the field of view studied here.
Dissociation cross sections of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons with nucleons
Authors: Ding Ruo-Qing , Xu Xiao-Ming , Weber H J 
Published: February 2024

Abstract
We study the dissociation of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons in collision with nucleons, which takes place in high-energy proton-nucleus collisions. The quark interchange between a nucleon and a

c

c

¯

meson leads to the dissociation of the

c

c

¯

meson. We consider the reactions:

pR
→

Λ

c

+

D

¯

0

,

pR
→

Λ

c

+

D

¯

*
0

,

pR
→

Σ

c

++

D

−

,

pR
→

Σ

c

++

D

*
−

,

pR
→

Σ

c

+

D

¯

0

,

pR
→

Σ

c

+

D

¯

*
0

,

pR
→

Σ

c

*
++

D

−

,

pR
→

Σ

c

*
++

D

*
−

,

pR
→

Σ

c

*
+

D

¯

0

, and

pR
→

Σ

c

*
+

D

¯

*
0

, where R stands for ψ(3770), ψ(4040), ψ(4160), or ψ(4415). A reaction of a neutron and a

c

c

¯

meson corresponds to a reaction of a proton and the

c

c

¯

meson by replacing the up quark with the down quark and vice versa. Transition-amplitude formulas are derived from the S-matrix element. Unpolarized cross sections are calculated with the transition amplitudes for scattering in the prior form and in the post form. The cross sections relate to nodes in the radial wave functions of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons.
Mobility and diffusion of intruders in granular suspensions: Einstein relation
Authors: Gómez González Rubén , Garzó Vicente 
Published: February 2024

Abstract
The Enskog kinetic equation is considered to determine the diffusion D and mobility λ transport coefficients of intruders immersed in a granular gas of inelastic hard spheres (grains). Intruders and grains are in contact with a thermal bath, which plays the role of a background gas. As usual, the influence of the latter on the dynamics of intruders and grains is accounted for via a viscous drag force plus a stochastic Langevin-like term proportional to the background temperature T
b. In this case, the starting kinetic equations are the Enskog and Enskog–Lorentz equations for grains and intruders, respectively, with the addition of Fokker–Planck terms to each one of the above equations. The transport coefficients λ and D are determined by solving the Enskog–Lorentz kinetic equation by means of the Chapman–Enskog method adapted to inelastic collisions. As for elastic collisions, both transport coefficients are given in terms of the solutions of two integral equations, which are approximately solved up to the second order in a Sonine polynomial expansion. Theoretical results are compared against numerical solutions of the inelastic Enskog equation by means of the direct simulation Monte Carlo method. In general, good agreement between theory and simulations is found, especially in the case of the second Sonine approximation. Knowledge of the coefficients λ and D allows us to assess the departure of the (conventional) Einstein relation

ϵ
=
D

/

(

T

b

λ
)

from 1. As expected from previous results for driven granular gases, it is shown that when the bath temperature T
b is replaced by the intruder temperature T
0 in the Einstein relation, the origin of the deviation of ε from 1 is only due to the non-Maxwellian behavior of the reference state of intruders (measured by the cumulant c
0). Since the magnitude of c
0 is in general very small, deviations of the (modified) Einstein relation

ϵ
0

=
D

/

(

T
0

λ
)

from 1 cannot be detected in computer simulations of dilute granular gases. This conclusion agrees well with previous computer simulation results.
Selected Mathematical Tools for Modeling in Tomography and Image Processing with Some Applications
Authors: Hjouj Fawaz 
Published: February 2024

Abstract
In this theoretical paper, we propose several useful mathematical tools for conducting research in the fields of tomography and image processing. Several mathematical models are presented including analytical formulation of the Radon transform for three elementary functions. A family of block binary images for testing ideas is explained. Representation of an image using the box function is suggested. This representation allows exact computations for the Radon transform, Fourier transform, moments, and many others. This representation can also be involved in the mathematical arrangements of the iterative reconstruction algorithms of tomography. Overall, we believe that these tools are helpful for researchers in these fields. We show accurate results in several calculations on synthetic images as well the algebraic reconstruction.
Quantum and quantum-inspired optimization for an in-core fuel management problem
Authors: Usmanov S R , Salakhov G V , Bozhedarov A A , Kiktenko E O , Fedorov A K 
Published: February 2024

Abstract
Operation management of nuclear power plants consists of several computationally hard problems. Searching for an in-core fuel loading pattern is among them. The main challenge of this combinatorial optimization problem is the exponential growth of the search space with a number of loading elements. Here we study a reloading problem in a Quadratic Unconstrained Binary Optimization (QUBO) form. Such a form allows us to apply various techniques, including quantum annealing, classical simulated annealing, and quantum-inspired algorithm in order to find fuel reloading patterns for several realistic configurations of nuclear reactors. We present the results of benchmarking the in-core fuel management problem in the QUBO form using the aforementioned computational techniques. This work demonstrates potential applications of quantum computers and quantum-inspired algorithms in the energy industry.
Description of Parameter Variation Learning with Artificial Intelligence and GeoGebra in Students of a Differential Equations Course
Authors: Olivares Funes Jorge , Valero Kari Elvis R. , Martin Pablo 
Published: February 2024

Abstract
In this era of social and technological change, the advent of AI has had great impact on the lives of many people and especially in the educational field, as mentioned in [1], wich prove that the perceptions that students and instructors have about artificial intelligence are very positive to implement them in learning. In this [2] assert that it is possible to have a collaborations between the fields of mathematics and artificial intelligence AI.
Simulation of Rarefied Gas Flow in a Channel Applying Artificial Neuron Network
Authors: Aksenova Olga , Khalidov Iskander 
Published: February 2024

Abstract
The purpose of the present paper is to confirm numerically applying our ANN algorithm for transitional gas flow between continuum and free-molecular flow. The main advantage of this approach is substantial computing time economy compared to usual DSMC procedure. The learning of ANN is based on well known rarefied gas flow examples, analytic solutions in limit cases, calculations by lattice Boltzmann method (LBM), and on quite few Monte Carlo simulations. Our previous results obtained for large Knudsen numbers have been applied near the free-molecular regime. In this region the flow has demonstrated the properties of unstable nonlinear dynamic system. The flow of nitrogen in a microchannel with aspect ratio L/h = 20 and by pressure ratio P between 1.84 and 4.14 is simulated by ANN. This example has shown a good coincidence of ANN and DSMC calculations even in the case when only a small part of original DSMC computation has been applied for learning ANN. Thus, computing time is reduced up to 10 times in this case.
Signal Quantification of Intravenous Contrast Agents Enhancement from Biphase Liver CT Scan Procedures
Authors: Alqam Rawa’ K. , Ahmad Muntaser S. , Mohammad Hjouj 
Published: February 2024

Abstract
In multi-detector computed tomography (MDCT) abdominal and pelvic CT treatments with intravenous (IV) contrast media (CM), automated bolus monitoring with a fixed contrast enhancement delay was examined. Statistics assess all contrast enhancement variables, including patient data like body weight, cardiac output, and contrast injection settings. This study comprised 100 retrospective and 43 prospective patients. In the first group, the Hounsfield unit (HU) was measured before, 30 seconds, and 70 seconds after CM. The second group measured age, weight, heart rate, systolic and diastolic blood pressure, and creatinine. The radiographer computed CM time based on HU values around 120. The differences in HU levels across groups were used to create an equation for imaging time prediction utilizing auto-mated bolus monitoring. The Bolus Time Equation’s predictors included patient weight, heart rate, creatinine level, and systolic blood pressure, with 34.9% dependency and 59.1% influence on each variable. The equation is trustworthy since the ANOVA test indicated p = 0.002. The computation and study gave the same Bolus Time value with a p-value of (0.992 > 0.05). The first and second groups exhibited very different HU rates (p-value 0.00). The research found that fixed-time improved more than bolus monitoring, which performed better.
A fold catastrophe potential illustrated with a pure mechanical apparatus
Authors: Fiolhais Manuel 
Published: February 2024

Abstract
We present an apparatus consisting of a bar tightly connected to a disc, that acts as a pulley, free to rotate around its axis. A body is suspended by means of a thread that is wrapped around the collar of the pulley. Depending on the values of the masses and also on the geometric parameters of the various parts of the apparatus, the system may, or may not, stay in static equilibrium. When it moves, the system may perform stable oscillations around stability positions, or the body continuously falls down, while the pulley executes a sequence of complete rotations. We analyse these very diverse behaviours, basing the discussion on the shape of the potential energy, plotted as a function of the angular position of the system, stressing that the experiment provides a very good example of a fold catastrophe potential, besides being funny and pedagogically very valuable.
Lift force on single bubbles in subcooled pool boiling systems: Experimental measurements and CFD simulations
Authors: Ganguli A A , Pandit A B 
Published: February 2024

Abstract
Lift coefficient has been evaluated for a subcooled pool boiling system with water as continuous phase and vapor (steam) bubble as dispersed phase generated on vertical walls with constant heat flux for a specific Rayleigh number (Ra) range (8x1012 < Ra < 2x1013) for the first time. Experimental investigation has been done with High Speed Camera while two phase CFD simulations have been performed using Volume of Fluid (VOF) method. The Morton number (M) for this system is log10M = -10.6 and Eötvös number (Eo) range is 0.2 < Eo < 1.3 while the shear rates have been maintained in the range 2 ≤ Sr ≤ 2.8. Bubble size of the bubbles arising from the sites on vertical surface have been determined by both experiments and simulations. The CFD predictions for bubble size and lift coefficients agree well with experimental measurements with a deviation of less than 10%. Further, empirical expressions from experimental data for the estimation of bubble size and lift coefficients have also been presented. The data for lift coefficients obtained is different from the ones of bubbles generated by single sparger in air-water systems.
Rough Surface Aerodynamic Computation in Rarefied Gas Flow Applying the Solution of Inverse Problem
Authors: Khalidov Iskander , Aksenova Olga 
Published: February 2024

Abstract
Most effective method to find the roughness parameters in rarefied gas flow is to calculate them from aerodynamic measurements, solving the inverse problem. The value of the main roughness parameter obtained from the solution of inverse problem is substantially higher (at least 1,25–1,5 times) than similar value of the same parameter measured from the profile diagrams. Thus, the effect of surface roughness in aerodynamic values of rough surface in rarefied gas flow is always significantly underestimated. First main reason of it is the low precision of roughness parameter measurements from the profile diagrams, and the second is based on usual lack of taking into account aerodynamic shadowing effect.