cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Observation of flat and weakly dispersing bands in a van der Waals semiconductor Nb3Br8 with breathing kagome lattice
Creators: name: Regmi, Sabin
name: Sakhya, Anup Pradhan
name: Fernando, Tharindu
name: Zhao, Yuzhou
name: Jeff, Dylan
name: Sprague, Milo
name: Gonzalez, Favian
name: Elius, Iftakhar Bin
name: Mondal, Mazharul Islam
name: Valadez, Nathan
name: Jarrett, Damani
name: Agosto, Alexis
name: Yang, Jihui
name: Chu, Jiun-Haw
name: Khondaker, Saiful I.
name: Xu, Xiaodong
name: Cao, Ting
name: Neupane, Madhab
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Niobium halides, Nb3X8 (X = Cl,Br,I), which are predicted two-dimensional magnets, have recently gotten attention due to their breathing kagome geometry. Here, we have studied the electronic structure of Nb3Br8 by using angle-resolved photoemission spectroscopy (ARPES) and first-principles calculations. ARPES results depict the presence of multiple flat and weakly dispersing bands. These bands are well explained by the theoretical calculations, which show they have Nb d character indicating their origination from the Nb atoms forming the breathing kagome plane. This van der Waals material can be easily thinned down via mechanical exfoliation to the ultrathin limit and such ultrathin samples are stable as depicted from the time-dependent Raman spectroscopy measurements at room temperature. These results demonstrate that Nb3Br8 is an excellent material not only for studying breathing kagome induced flat band physics and its connection with magnetism, but also for heterostructure fabrication for application purposes.
description: 24 pages, 12 figures, Supplemental Material included
Uniqueness of bubbling solutions of mean field equations
Creators: name: Bartolucci, Daniele
name: Jevnikar, Aleks
name: Lee, Youngae
name: Yang, Wen
Publisher: name: arXiv
Year: 2017
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 35J61, 35J20, 35R01, 35B44

description: We prove uniqueness of blow up solutions of the mean field equation as $ρ_n \rightarrow 8πm$, $m\in\mathbb{N}$. If $u_{n,1}$ and $u_{n,2}$ are two sequences of bubbling solutions with the same $ρ_n$ and the same (non degenerate) blow up set, then $u_{n,1}=u_{n,2}$ for sufficiently large $n$. The proof of the uniqueness requires a careful use of some sharp estimates for bubbling solutions of mean field equations [24] and a rather involved analysis of suitably defined Pohozaev-type identities as recently developed in [51] in the context of the Chern-Simons-Higgs equations. Moreover, motivated by the Onsager statistical description of two dimensional turbulence, we are bound to obtain a refined version of an estimate about $ρ_n-8πm$ in case the first order evaluated in [24] vanishes.
description: Accepted for JMPA
Single freeform surface design for prescribed input wavefront and target irradiance
Creators: name: Bösel, Christoph
name: Gross, Herbert
Publisher: name: arXiv
Year: 2017
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: In beam shaping applications, the minimization of the number of necessary optical elements for the beam shaping process can benefit the compactness of the optical system and reduce its cost. The single freeform surface design for input wavefronts, which are neither planar nor spherical, is therefore of interest. In this work, the design of single freeform surfaces for a given zero-étendue source and complex target irradiances is investigated. Hence, not only collimated input beams or point sources are assumed. Instead, a predefined input ray direction vector field and irradiance distribution on a source plane, which has to be redistributed by a single freeform surface to give the predefined target irradiance, is considered. To solve this design problem, a partial differential equation (PDE) or PDE system, respectively, for the unknown surface and its corresponding ray mapping is derived from energy conservation and the ray-tracing equations. In contrast to former PDE formulations of the single freeform design problem, the derived PDE of Monge-Ampère type is formulated for general zero-étendue sources in cartesian coordinates. The PDE system is discretized with finite differences and the resulting nonlinear equation system solved by a root-finding algorithm. The basis of the efficient solution of the PDE system builds the introduction of an initial iterate constuction approach for a given input direction vector field, which uses optimal mass transport with a quadratic cost function. After a detailed description of the numerical algorithm, the efficiency of the design method is demonstrated by applying it to several design examples. This includes the redistribution of a collimated input beam beyond the paraxial approximation, the shaping of point source radiation and the shaping of an astigmatic input wavefront into a complex target irradiance distribution.
description: 11 pages, 10 figures version 2: Equation (7) was corrected; additional minor changes/improvements
Fractal Analyses Reveal Independent Complexity and Predictability of Gait
Creators: name: Dierick, F.
name: Nivard, A. -L.
name: White, O.
name: Buisseret, F.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Medical Physics (physics.med-ph)
subject: FOS: Physical sciences

description: Locomotion is a natural task that has been assessed since decades and used as a proxy to highlight impairments of various origins. Most studies adopted classical linear analyses of spatio-temporal gait parameters. Here, we use more advanced, yet not less practical, non-linear techniques to analyse gait time series of healthy subjects. We aimed at finding more sensitive indexes related to spatio-temporal gait parameters than those previously used, with the hope to better identify abnormal locomotion. We analysed large-scale stride interval time series and mean step width in 34 participants while altering walking direction (forward vs. backward walking) and with or without galvanic vestibular stimulation. The Hurst exponent $α$ and the Minkowski fractal dimension $D$ were computed and interpreted as indexes expressing predictability and complexity of stride interval time series, respectively. We show that $α$ and $D$ accurately capture stride interval changes in function of the experimental condition. Walking forward exhibited maximal complexity ($D$) and hence, adaptability. In contrast, any perturbation (walking backward and/or stimulation of the vestibular system) decreased it. Furthermore, walking backward increased predictability ($α$) through a more stereotyped pattern of the stride interval and galvanic vestibular stimulation reduced predictability. The present study demonstrates the complementary power of the Hurst exponent and the fractal dimension to improve walking classification. These holistic indexes can easily be interpreted in the framework of optimal movement complexity. Our developments may have immediate applications in rehabilitation, diagnosis, and classification procedures.
description: Technical details and results extended in v2, conclusions unchanged
News-driven Expectations and Volatility Clustering
Creators: name: Inoua, Sabiou
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Finance (q-fin.GN)
subject: Theoretical Economics (econ.TH)
subject: FOS: Economics and business

description: Financial volatility obeys two fascinating empirical regularities that apply to various assets, on various markets, and on various time scales: it is fat-tailed (more precisely power-law distributed) and it tends to be clustered in time. Many interesting models have been proposed to account for these regularities, notably agent-based models, which mimic the two empirical laws through a complex mix of nonlinear mechanisms such as traders' switching between trading strategies in highly nonlinear way. This paper explains the two regularities simply in terms of traders' attitudes towards news, an explanation that follows almost by definition of the traditional dichotomy of financial market participants, investors versus speculators, whose behaviors are reduced to their simplest forms. Long-run investors' valuations of an asset are assumed to follow a news-driven random walk, thus capturing the investors' persistent, long memory of fundamental news. Short-term speculators' anticipated returns, on the other hand, are assumed to follow a news-driven autoregressive process, capturing their shorter memory of fundamental news, and, by the same token, the feedback intrinsic to the short-sighted, trend-following (or herding) mindset of speculators. These simple, linear, models of traders' expectations, it is shown, explain the two financial regularities in a generic and robust way. Rational expectations, the dominant model of traders' expectations, is not assumed here, owing to the famous no-speculation, no-trade results
Monogamy inequality for entanglement and local contextuality
Creators: name: Camalet, S.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We derive a monogamy inequality for entanglement and local contextuality, for any finite bipartite system. It essentially results from the relations between the purity of a local state and the entanglement of the global state, and between the purity of a state and its ability to violate a given noncontextuality inequality. We build an explicit entanglement monotone that satisfies the found monogamy inequality. An important consequence of this inequality, is that there are global states too entangled to violate the local noncontextuality inequality.
title: On a new monoclinic SFC polytype
Creators: name: Krüger, Biljana
name: Grabowski, Janina
name: Kahlenberg, Volker
Publisher: name: Deutsche Geologische Gesellschaft - Geologische Vereinigung e.V. (DGGV)
Year: 2022

description:
Dark red crystals of a silico-ferrite of calcium (SFC) with composition Ca5.34Fe20.55Si2.12O40 have been obtained from synthesis experiments at 1250°C. The SFC phase crystalizes in space group C2/c with the following lattice parameters: a= 9.981(4) Å, b= 15.283(6) Å, c= 5.303(2) Å, β = 99.88(4)°, Z=1.

The structural formula of the new phase can be written as VIIA4 VI(M1M2M3M4)Σ12O4[IV(T12T22)Σ12O36], where A represents a seven coordinated Ca-site, M=Fe,Ca are octahedral sites and T=Fe,Si are tetrahedral positions. The structure is composed of spinel(S)- and pyroxene(P)-type modules.

The SFC structure is closely related to that of the minerals of the rhönite group (sapphirine supergroup) and synthetic so-called SFCA phases (Silico-ferrite of calcium and aluminum), where different polytypes composed of the same fundamental S- and P-modules have been observed.

The new monoclinic SFC phase exhibits disorder in the spinel module, representing a layer with edge-sharing zig-zag octahedral chains connected via tetrahedra. Two of three octahedral sites in these chains and the connecting tetrahedra are half occupied only. This enables two (left and right) orientations of the chains along [-1 0 -1]. The same arrangement is observed in equivalent layers of a triclinic SFCA phase reported by Liles et al. (2016). However, in this compound two possible configurations of these layers allow for stacking faults.

Liles, D.C., de Villiers, J.P.R. & Kahlenberg, V. (2016): Miner Petrol 110:141–147.
BCFT and OSFT moduli: an exact perturbative comparison
Creators: name: Larocca, Pier Vittorio
name: Maccaferri, Carlo
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Starting from the pseudo-${\cal B}_0$ gauge solution for marginal deformations in OSFT, we analytically compute the relation between the perturbative deformation parameter $\tildeλ$ in the solution and the BCFT marginal parameter $λ$, up to fifth order, by evaluating the Ellwood invariants. We observe that the microscopic reason why $\tildeλ$ and $λ$ are different is that the OSFT propagator renormalizes contact term divergences differently from the contour deformation used in BCFT
description: 26+5 pages, 10 figures V2: minor improvements, published version
BLASFEO: basic linear algebra subroutines for embedded optimization
Creators: name: Frison, Gianluca
name: Kouzoupis, Dimitris
name: Sartor, Tommaso
name: Zanelli, Andrea
name: Diehl, Moritz
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mathematical Software (cs.MS)
subject: FOS: Computer and information sciences

description: BLASFEO is a dense linear algebra library providing high-performance implementations of BLAS- and LAPACK-like routines for use in embedded optimization. A key difference with respect to existing high-performance implementations of BLAS is that the computational performance is optimized for small to medium scale matrices, i.e., for sizes up to a few hundred. BLASFEO comes with three different implementations: a high-performance implementation aiming at providing the highest performance for matrices fitting in cache, a reference implementation providing portability and embeddability and optimized for very small matrices, and a wrapper to standard BLAS and LAPACK providing high-performance on large matrices. The three implementations of BLASFEO together provide high-performance dense linear algebra routines for matrices ranging from very small to large. Compared to both open-source and proprietary highly-tuned BLAS libraries, for matrices of size up to about one hundred the high-performance implementation of BLASFEO is about 20-30% faster than the corresponding level 3 BLAS routines and 2-3 times faster than the corresponding LAPACK routines.
Isotope and density profile effects on pedestal neoclassical transport
Creators: name: Buller, Stefan
name: Pusztai, Istvan
Publisher: name: arXiv
Year: 2017
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: Cross-field neoclassical transport of heat, particles and momentum is studied in sharp density pedestals, with a focus on isotope and profile effects, using a radially global approach. Global effects -- which tend to reduce the peak ion heat flux, and shift it outward -- increase with isotope mass for fixed profiles. The heat flux reduction exhibits a saturation with a favorable isotopic trend. A significant part of the heat flux can be convective even in pure plasmas, unlike in the plasma core, and it is sensitive to how momentum sources are distributed between the various species. In particular, if only ion momentum sources are allowed, in global simulations of pure plasmas the ion particle flux remains close to its local value, while this may not be the case for simulations with isotope mixtures or electron momentum sources. The radial angular momentum transport that is a finite orbit width effect, is found to be strongly correlated with heat sources.
description: 17 pages, 15 figures
A new class of multiple nonlocal problems with two parameters and variable-order fractional $p(\cdot)$-Laplacian
Creators: name: Hamdani, Mohamed Karim
name: Mbarki, Lamine
name: Allaoui, Mostafa
Publisher: name: arXiv
Year: 2023
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 35J60, 35J20

description: In the present manuscript, we focus on a novel tri-nonlocal Kirchhoff problem, which involves the $p(x)$-fractional Laplacian equations of variable order. The problem is stated as follows: \begin{eqnarray*} \left\{ \begin{array}{ll} M\Big(σ_{p(x,y)}(u)\Big)(-Δ)^{s(\cdot)}_{p(\cdot)}u(x) =λ|u|^{q(x)-2}u\left(\int_Ø\frac{1}{q(x)} |u|^{q(x)}dx \right)^{k_1}+β|u|^{r(x)-2}u\left(\int_Ø\frac{1}{r(x)} |u|^{r(x)}dx \right)^{k_2} \quad \mbox{in }Ω, \\ u=0 \quad \mbox{on }\partialΩ, \end{array} \right. \end{eqnarray*} where the nonlocal term is defined as $$ σ_{p(x,y)}(u)=\int_{Ω\times Ω}\frac{1}{p(x,y)}\frac{|u(x)-u(y)|^{p(x,y)}}{|x-y|^{N+s(x,y)p(x,y)}} \,dx\,dy. $$ Here, $Ω\subset\mathbb{R}^{N}$ represents a bounded smooth domain with at least $N\geq2$. The function $M(s)$ is given by $M(s) = a - bs^γ$, where $a\geq 0$, $b>0$, and $γ>0$. The parameters $k_1$, $k_2$, $λ$ and $β$ are real parameters, while the variables $p(x)$, $s(\cdot)$, $q(x)$, and $r(x)$ are continuous and can change with respect to $x$. To tackle this problem, we employ some new methods and variational approaches along with two specific methods, namely the Fountain theorem and the symmetric Mountain Pass theorem. By utilizing these techniques, we establish the existence and multiplicity of solutions for this problem separately in two distinct cases: when $a>0$ and when $a=0$. To the best of our knowledge, these results are the first contributions to research on the variable-order $p(x)$-fractional Laplacian operator.
description: 21 pages
Thermal conductivity decomposition in two-dimensional materials: Application to graphene
Creators: name: Fan, Zheyong
name: Pereira, Luiz Felipe C.
name: Hirvonen, Petri
name: Ervasti, Mikko M.
name: Elder, Ken R.
name: Donadio, Davide
name: Ala-Nissila, Tapio
name: Harju, Ari
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Two-dimensional materials have unusual phonon structures due to the presence of flexural (out-of-plane) modes. Although molecular dynamics simulations have been extensively used to study heat transport in such materials, conventional formalisms treat the phonon dynamics isotropically. Here, we decompose the microscopic heat current in atomistic simulations into in-plane and out-of-plane components, corresponding to the in-plane and out-of-plane phonon dynamics, respectively. This decomposition allows for direct computation of the corresponding thermal conductivity components in two-dimensional materials. We apply this decomposition to study heat transport in suspended graphene, using both equilibrium and non-equilibrium molecular dynamics simulations. We show that the flexural component is responsible for about two thirds of the total thermal conductivity in unstrained graphene, and the acoustic flexural component is responsible for the logarithmic divergence of the conductivity when a sufficiently large tensile strain is applied.
description: 12 pages, 9 figures
Supplementary Material for Effective relationship between characteristics of training data and learning progress on knowledge distillation
Creators: Anonymous
Publisher: name: IEEE Signal Processing Society
Year: 2025

description: In image recognition, knowledge distillation is a valuable approach to train a compact model with high accuracy by exploiting outputs of a highly accurate large model as correct labels. In knowledge distillation, studies have shown the usefulness of data with high entropy output generated by image mix data augmentation techniques. Other strategies such as curriculum learning have also been proposed to improve model generalization by the control of the difficulty of training data over the learning process. In this paper, we explore the relationship between the learning process and data characteristics, focusing on the entropy of output distribution and learning difficulty in knowledge distillation. To validate this relationship, we propose a method to readily generate data that yields high entropy output and adjust the degree of learning difficulty by controlling bounds and a sampling range for mix ratios in mixing images between classes. In evaluation experiments using multiple datasets, our proposed method outperformed conventional approaches in terms of accuracy.
String theory duals of Wilson loops from Higgsing
Creators: name: Lietti, Marco
name: Mauri, Andrea
name: Penati, Silvia
name: Zhang, Jia-ju
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: For three-dimensional ABJ(M) theories and $\mathcal N=4$ Chern-Simons-matter quiver theories, we construct two sets of 1/2 BPS Wilson loop operators by applying the Higgsing procedure along independent directions of the moduli space, and choosing different massive modes. For theories whose dual M-theory description is known, we also determine the corresponding spectrum of 1/2 BPS M2-brane solutions. We identify the supercharges in M-theory and field theory, as well as the supercharges preserved by M2-/anti-M2-branes and 1/2 BPS Wilson loops. In particular, in $\mathcal N=4$ orbifold ABJM theory we find pairs of different 1/2 BPS Wilson loops that preserve exactly the same set of supercharges. In field theory they arise by Higgsing with the choice of either particles or antiparticles, whereas in the dual description they correspond to a pair of M2-/anti-M2-branes localized at different positions in the compact space. This result enlightens the origin of classical Wilson loop degeneracy in these theories, already discussed in arXiv:1506.07614. A discussion on possible scenarios that emerge by comparison with localization results is included.
description: 52 pages, 4 figures; V2, 61 pages, 4 figures, supercharges in gravity and field theory identified, conclusion unchanged, published version
Aggressive Sampling for Multi-class to Binary Reduction with Applications to Text Classification
Creators: name: Joshi, Bikash
name: Amini, Massih-Reza
name: Partalas, Ioannis
name: Iutzeler, Franck
name: Maximov, Yury
Publisher: name: arXiv
Year: 2017
Subjects: subject: Machine Learning (stat.ML)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: We address the problem of multi-class classification in the case where the number of classes is very large. We propose a double sampling strategy on top of a multi-class to binary reduction strategy, which transforms the original multi-class problem into a binary classification problem over pairs of examples. The aim of the sampling strategy is to overcome the curse of long-tailed class distributions exhibited in majority of large-scale multi-class classification problems and to reduce the number of pairs of examples in the expanded data. We show that this strategy does not alter the consistency of the empirical risk minimization principle defined over the double sample reduction. Experiments are carried out on DMOZ and Wikipedia collections with 10,000 to 100,000 classes where we show the efficiency of the proposed approach in terms of training and prediction time, memory consumption, and predictive performance with respect to state-of-the-art approaches.
description: 16 pages, 3 figures
Quantum Oscillations in the Anomalous Spin Density Wave State of FeAs
Creators: name: Campbell, Daniel J.
name: Eckberg, Chris
name: Wang, Kefeng
name: Wang, Limin
name: Hodovanets, Halyna
name: Graf, Dave
name: Parker, David
name: Paglione, Johnpierre
Publisher: name: arXiv
Year: 2017
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Quantum oscillations in the binary antiferromagnetic metal FeAs are presented and compared to theoretical predictions for the electronic band structure in the anomalous spin density wave state of this material. Demonstrating a new method for growing single crystals out of Bi flux, we utilize the highest quality FeAs to perform torque magnetometry experiments up to 35 T, using rotations of field angle in two planes to provide evidence for one electron and one hole band in the magnetically ordered state. The resulting picture agrees with previous experimental evidence for multiple carriers at low temperatures, but the exact Fermi surface shape differs from predictions, suggesting that correlations play a role in deviation from ab initio theory and cause up to a four-fold enhancement in the effective carrier mass.
description: 8 pages, 5 figures
title: Reconstruction of paleoredox conditions in the Upper Jurassic - Lower Cretaceous Bazhenov Sea (West Siberian Basin, Russia)
Creators: name: Burnaz, Linda
name: Grohmann, Sebastian
name: Littke, Ralf
Publisher: name: Deutsche Geologische Gesellschaft - Geologische Vereinigung e.V. (DGGV)
Year: 2022

description:
The Bazhenov Sea covered around 2 million km2 of the Mesozoic West Siberian Basin (WSB) during Volgian to Early Berrasian times, resulting in the deposition of highly organic-rich black shales as part of the stratigraphic unit "Bazhenov Horizon". As black shales are excellent archives for past large- to small-scale sedimentary systems, the study's objective is to develop a detailed depositional model reconstructing the transgression-regression cyclicity, paleoredox conditions, paleosulfidicity and -bioproductivity that prevailed during the black shales' sedimentation, and to infer insights into the primary forces and mechanisms favouring enhanced organic matter preservation and accumulation.

For this, elemental analysis, Rock-Eval pyrolysis and petrographic observations were carried out on a large number of core samples from seven well sections from the south-western WSB (Frolov region). Systematic inorganic and organic composition patterns reveal sequential and regional variations of sedimentary and diagenetic conditions in the study area.

The obtained data show that the sediments were deposited in a marine environment with significant contribution of authigenic minerals and subordinate detrital influence. The enrichment of redox-sensitive inorganic and organic compounds indicates reducing and periodically sulfidic conditions in the bottom and uppermost pore water columns during deposition. Sections that show evidence of anoxia or euxinic conditions simultaneously have the lowest terrigenous influence, suggesting that anoxia is closely linked to sea-level fluctuations in the course of eustatic transgression-regression cycles. The correlation of organic matter and redox proxy enrichments suggests that organic matter accumulation and preservation are mainly controlled by these paleoredox condition variations linked to regression-transgression cyclicity.
Effective equilibrium states in the colored-noise model for active matter II. A unified framework for phase equilibria, structure and mechanical properties
Creators: name: Wittmann, René
name: Marconi, Umberto Marini Bettolo
name: Maggi, Claudio
name: Brader, Joseph M.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: Active particles driven by colored noise can be approximately mapped onto a system that obeys detailed balance. The effective interactions which can be derived for such a system allow to describe the structure and phase behavior of the active fluid by means of an effective free energy. In this paper we explain why the related thermodynamic results for pressure and interfacial tension do not represent the results one would measure mechanically. We derive a dynamical density functional theory, which in the steady state simultaneously validates the use of effective interactions and provides access to mechanical quantities. Our calculations suggest that in the colored-noise model the mechanical pressure in coexisting phases might be unequal and the interfacial tension can become negative.
A classification of 3+1D bosonic topological orders (I): the case when point-like excitations are all bosons
Creators: name: Lan, Tian
name: Kong, Liang
name: Wen, Xiao-Gang
Publisher: name: arXiv
Year: 2017
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Topological orders are new phases of matter beyond Landau symmetry breaking. They correspond to patterns of long-range entanglement. In recent years, it was shown that in 1+1D bosonic systems there is no nontrivial topological order, while in 2+1D bosonic systems the topological orders are classified by a pair: a modular tensor category and a chiral central charge. In this paper, we propose a partial classification of topological orders for 3+1D bosonic systems: If all the point-like excitations are bosons, then such topological orders are classified by unitary pointed fusion 2-categories, which are one-to-one labeled by a finite group $G$ and its group 4-cocycle $ω_4 \in \mathcal H^4[G;U(1)]$ up to group automorphisms. Furthermore, all such 3+1D topological orders can be realized by Dijkgraaf-Witten gauge theories.
description: An important new result "Untwisted sector of dimension reduction is the Drinfeld center of E" is added in Sec. IIIC; other minor refinements and improvements; 23 pages, 10 figures
Flattened photon beams, an obsolete feature in modern linear accelerators
Creators: name: Parsai, E. Ishmael
name: Salari, Elahheh
name: Shvydka, Diana
name: Wan, Jui
Publisher: name: arXiv
Year: 2023
Subjects: subject: Medical Physics (physics.med-ph)
subject: FOS: Physical sciences

description: Background: With the advent of Intensity Modulated Radiotherapy (IMRT) and recently, Volumetric Modulated Arc Therapy (VMAT), treatment planning using Flattening Filter Free (FFF) beams can meet all of the energy requirements in radiation therapy clinics. Manufacturers of linear accelerators no longer need to install a flattening filter (FF) in gantry head. This study aims to provide evidence of the superiority of FFF to FF through both dosimetric measurements and clinical treatment plans. Materials and Methods: A 50x50x50cm3 water phantom was created in the RayStation treatment planning system (TPS) for dosimetry comparisons. Flat beam profiles were generated using FFF beam through an optimization process for 10x10 to 30x30cm2 field sizes. Next, a comparison of treatment plans was made using 21 Head and Neck and 14 Lung/Mediastinum treatment sites using 6MV and 6MV-FFF beams. Results: Using FFF beams, profiles with flatness and symmetry identical to or better than those of the flattened beams were produced. At the very edge of the optimized plans for FFF beams, horns had the highest gamma index deviation <1.5% of the normalized dose. For clinical plans evaluated, most of the mean doses to organs_atrisk (OAR) volumes receiving 5% to 30% of the prescription dose were reduced with FFF beams. Conclusion: These results indicate the feasibility of delivering flat beams with FFF quality and producing treatment plans with equal or higher qualities in PTV coverage while achieving better sparing of OAR which will allow escalation of target dose if desired. Plus, removing FF will simplify the gantry head and reduces quality assurance and machine maintenance efforts.
description: 6 pages, 10 Figures, 2 Tables. International Journal of Radiation Research, October 2022
title: Holocaust Education ohne Antisemitismus
Creators: name: Rajal, Elke
Publisher: name: Katholische Hochschule Nordrhein-Westfalen, Köln
Year: 2022
Subjects: subject: 300 Sozialwissenschaften

description: Obwohl es unbestritten ist, dass es ohne Antisemitismus keine Shoah gegeben hätte, wird in der zeitgenössischen Vermittlungsarbeit zur Shoah – oft auch Holocaust Education genannt – der Antisemitismus häufig ausgespart oder bildet eine Randnotiz. Der vorliegende Text argumentiert für einen stärkeren Einbezug der Thematik des Antisemitismus in die Holocaust Education, ohne zu behaupten, dass es alleine die Aufgabe von Holocaust Education wäre, Antisemitismuskritik zu vermitteln. Nach einer kurzen Einführung in Debatten rund um den Zusammenhang zwischen Shoah und Antisemitismus werden die mit Holocaust Education verbundenen Ziele kritisch beleuchtet. Danach wird der gegenwärtig eingeräumte Stellenwert von Antisemitismus in der Bildungsarbeit zur Shoah ausgelotet und es werden vor dem Hintergrund der Kritischen Theorie einige Anregungen für die pädagogische Arbeit gegeben. Der Text schließt mit einem Plädoyer für eine schulische sowie außerschulische Vermittlungsarbeit, welche die enge Verklammerung von Shoah und Antisemitismus ernstnimmt, ohne das eine Phänomen auf das andere zu reduzieren.
description: CARS Working Papers; 10
Item Recommendation with Continuous Experience Evolution of Users using Brownian Motion
Creators: name: Mukherjee, Subhabrata
name: Guennemann, Stephan
name: Weikum, Gerhard
Publisher: name: arXiv
Year: 2017
Subjects: subject: Artificial Intelligence (cs.AI)
subject: Computation and Language (cs.CL)
subject: Information Retrieval (cs.IR)
subject: Social and Information Networks (cs.SI)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: Online review communities are dynamic as users join and leave, adopt new vocabulary, and adapt to evolving trends. Recent work has shown that recommender systems benefit from explicit consideration of user experience. However, prior work assumes a fixed number of discrete experience levels, whereas in reality users gain experience and mature continuously over time. This paper presents a new model that captures the continuous evolution of user experience, and the resulting language model in reviews and other posts. Our model is unsupervised and combines principles of Geometric Brownian Motion, Brownian Motion, and Latent Dirichlet Allocation to trace a smooth temporal progression of user experience and language model respectively. We develop practical algorithms for estimating the model parameters from data and for inference with our model (e.g., to recommend items). Extensive experiments with five real-world datasets show that our model not only fits data better than discrete-model baselines, but also outperforms state-of-the-art methods for predicting item ratings.
Differentiating Radiation Necrosis and Metastatic Progression in Brain Tumors Using Radiomics and Machine Learning
Creators: name: Salari, Elahheh
name: Elsamaloty, Haitham
name: Ray, Aniruddha
name: Hadziahmetovic, Mersiha
name: Parsai, E. Ishmael
Publisher: name: arXiv
Year: 2023
Subjects: subject: Medical Physics (physics.med-ph)
subject: FOS: Physical sciences

description: Objectives: Distinguishing between radiation necrosis(RN) and metastatic progression is extremely challenging due to their similarity in conventional imaging. This is crucial from a therapeutic point of view as this determines the outcome of the treatment. This study aims to establish an automated technique to differentiate RN from brain metastasis progression using radiomics with machine learning. Methods: 86 patients with brain metastasis after they underwent stereotactic radiosurgery as primary treatment were selected. Discrete wavelets transform, Laplacian-of-Gaussian, Gradient, and Square were applied to magnetic resonance post-contrast T1-weighted images to extract radiomics features. After feature selection, dataset was randomly split into train/test (80%/20%) datasets. Random forest classification(RFC), logistic regression, and support vector classification(SVC) were trained and subsequently validated using test set. The classification performance was measured by area under the curve(AUC) value of receiver operating characteristic curve, accuracy, sensitivity, and specificity. Results: The best performance was achieved using RFC with a Gradient filter (AUC=0.910, std=0.047), (accuracy 0.8, std=0.071), (sensitivity=0.796 std=0.055), (specificity =0.922, std=0.059). For SVC the best result obtains using wavelet_HHH with a high AUC of 0.890 with std=0.89, accuracy of 0.777 with std=0.062, sensitivity=0.701, std=0.084, and specificity=0.85 with std=0.112. Logistic regression using wavelet_HHH provides a poor result with AUC=0.882 & std=0.051, accuracy of 0.753 & std=0.08, sensitivity=0.717 & std=0.208, and specificity=0.816 with std=0.123. Conclusion: This type of machine-learning approach can help accurately distinguish RN from recurrence in magnetic resonance imaging, without the need for biopsy. This has the potential to improve the therapeutic outcome.
description: 10 pages, 4 Figures, 2 Tables. American Journal of Clinical Oncology, August 2023
Super-compact universal quantum logic gates with inversedesigned elements
Creators: name: He, Lu
name: Liu, Dongning
name: Gao, Jingxing
name: Zhang, Weixuan
name: Zhang, Huizhen
name: Feng, Xue
name: Huang, Yidong
name: Cui, Kaiyu
name: Liu, Fang
name: Zhang, Wei
name: Zhang, Xiangdong
Publisher: name: arXiv
Year: 2023
Subjects: subject: Optics (physics.optics)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Integrated quantum photonic circuit is a promising platform for the realization of quantum information processing in the future. To achieve the largescale quantum photonic circuits, the applied quantum logic gates should be as small as possible for the high-density integration on chips. Here, we report the implementation of super-compact universal quantum logic gates on silicon chips by the method of inverse design. In particular, the fabricated controlled-NOT gate and Hadamard gate are both nearly a vacuum wavelength, being the smallest optical quantum gates reported up to now. We further design the quantum circuit by cascading these fundamental gates to perform arbitrary quantum processing, where the corresponding size is about several orders smaller than that of previous quantum photonic circuits. Our study paves the way for the realization of largescale quantum photonic chips with integrated sources, and can possess important applications in the field of quantum information processes.
Experimental topological quantum computing with electric circuits
Creators: name: Zou, Deyuan
name: Pan, Naiqiao
name: Chen, Tian
name: Sun, Houjun
name: Zhang, Xiangdong
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The key obstacle to the realization of a scalable quantum computer is overcoming environmental and control errors. Topological quantum computation has attracted great attention because it has emerged as one of the most promising approaches to solving these problems. Various theoretical schemes for building topological quantum computation have been proposed. However, experimental implementation has always been a great challenge because it has proved to be extremely difficult to create and manipulate topological qubits in real systems. Therefore, topological quantum computation has not been realized in experiments yet. Here, we report the first experimental realization of topological quantum computation with electric circuits. Based on our proposed new scheme with circuits, Majorana-like edge states are not only observed experimentally, but also T junctions are constructed for the braiding process. Furthermore, we demonstrate the feasibility of topological quantum computing through a set of one- and two-qubit unitary operations. Finally, our implementation of Grover's search algorithm demonstrates that topological quantum computation is ideally suited for such tasks.
Análise de dados de satélite na prospeção geológica: contribuição da deteção remota na geologia
Creators: name: Gonçalo, Monteiro
Publisher: name: Zenodo
Year: 2024
Subjects: deteção remota
análise de dados
prospeção
satélite

description: Relatório de Estágio para a conclusão do grau de Licenciatura em Geologia (Faculdade de Ciências da Universidade do Porto) apresentado no ano letivo 2022-2023. Este relatório de estágio foi realizado no enquadramento do projeto Horizon Europe - S34I. O conteúdo é da inteira responsabilidade do autor.

Internship report for completion of the Bachelor's Degree in Geology (Faculty of Sciences of the University of Porto) presented in the academic year 2022-2023. This internship report was carried out within the scope of the Horizon Europe - S34I project. The content is the sole responsibility of the author.
title: Influence of Quaternary glaciations on subsurface temperatures, pore pressures, rock properties and petroleum systems in the onshore northeastern Netherlands
Creators: name: Amberg, Sebastian
name: Sachse, Victoria
name: Littke, Ralf
name: Back, Stefan
Publisher: name: Deutsche Geologische Gesellschaft - Geologische Vereinigung e.V. (DGGV)
Year: 2022

description:
Pleistocene ice ages had a profound influence on the subsurface, in parts, until the present day. Ice masses during glacial advances partly covered onshore Netherlands during two glacial periods, the Elsterian and Saalian stages. This study presents a 3D basin and petroleum systems model of the northeastern Netherlands with implemented glacial stages to address the influence of low surface temperatures and the mechanical loading of ice sheets on the subsurface. Two ice sheet thickness scenarios were used to constrain results based on published ice sheet thickness estimates.

Overall, Quaternary glacial stages substantially impact the temperature and pressure distribution in the subsurface. Subsurface temperatures are significantly reduced during glacial stages, leading to lowered present-day temperatures and a low geothermal gradient in the shallow subsurface. In deeply buried sedimentary formations, pressures build up with every glacial advance resulting in overpressures at the present day. Glacial stages do not directly influence the petroleum generation of petroleum source rocks in the area, but high pressures during loading might have impacted petroleum expulsion of the early mature Coevorden Formation. Hydrocarbon accumulations in the Lower Saxony Basin were simulated to investigate the possible effects of mechanical ice loading and unloading on hydrocarbon migration. A loss of Coevorden Formation-sourced hydrocarbons to the surface was calculated in the Lower Saxony Basin during the glacial stages, indicating an influence of glacial loading on the Mesozoic petroleum system.
Cusps Enable Line Attractors for Neural Computation
Creators: name: Xiao, Zhuocheng
name: Zhang, Jiwei
name: Sornborger, Andrew T.
name: Tao, Louis
Publisher: name: arXiv
Year: 2017
Subjects: subject: Neurons and Cognition (q-bio.NC)
subject: FOS: Biological sciences

description: Line attractors in neuronal networks have been suggested to be the basis of many brain functions, such as working memory, oculomotor control, head movement, locomotion, and sensory processing. In this paper, we make the connection between line attractors and pulse-gating in feedforward neuronal networks. In this context, because of their neutral stability along a one-dimensional manifold, line attractors are associated with a time-translational invariance that allows graded information to be propagated from one neuronal population to the next. To understand how pulse-gating manifests itself in a high-dimensional, non-linear, feedforward integrate-and-fire network, we use a Fokker-Planck approach to analyze system dynamics. We make a connection between pulse-gated propagation in the Fokker-Planck and population-averaged mean-field (firing rate) models, then identify an approximate line attractor in state space as the essential structure underlying graded information propagation. An analysis of the line attractor shows that it consists of three fixed points: a central saddle with an unstable manifold along the line and stable manifolds orthogonal to the line, which is surrounded on either side by stable fixed points. Along the manifold defined by the fixed points, slow dynamics give rise to a ghost. We show that this line attractor arises at a cusp catastrophe, where a fold bifurcation develops as a function of synaptic noise; and that the ghost dynamics near the fold of the cusp underly the robustness of the line attractor. Understanding the dynamical aspects of this cusp catastrophe allows us to show how line attractors can persist in biologically realistic neuronal networks and how the interplay of pulse gating, synaptic coupling and neuronal stochasticity can be used to enable attracting one-dimensional manifolds and thus, dynamically control the processing of graded information.
description: 7 pages, 5 figures
Epsilon-shapes: characterizing, detecting and thickening thin features in geometric models
Creators: name: Cabiddu, Daniela
name: Attene, Marco
Publisher: name: arXiv
Year: 2017
Subjects: subject: Computational Geometry (cs.CG)
subject: Graphics (cs.GR)
subject: FOS: Computer and information sciences

description: We focus on the analysis of planar shapes and solid objects having thin features and propose a new mathematical model to characterize them. Based on our model, that we call an epsilon-shape, we show how thin parts can be effectively and efficiently detected by an algorithm, and propose a novel approach to thicken these features while leaving all the other parts of the shape unchanged. When compared with state-of-the-art solutions, our proposal proves to be particularly flexible, efficient and stable, and does not require any unintuitive parameter to fine-tune the process. Furthermore, our method is able to detect thin features both in the object and in its complement, thus providing a useful tool to detect thin cavities and narrow channels. We discuss the importance of this kind of analysis in the design of robust structures and in the creation of geometry to be fabricated with modern additive manufacturing technology.
Geometrically nonlinear Cosserat elasticity in the plane: applications to chirality
Creators: name: Bahamonde, Sebastian
name: Boehmer, Christian G.
name: Neff, Patrizio
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mathematical Physics (math-ph)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Modelling two-dimensional chiral materials is a challenging problem in continuum mechanics because three-dimensional theories reduced to isotropic two-dimensional problems become non-chiral. Various approaches have been suggested to overcome this problem. We propose a new approach to this problem by formulating an intrinsically two-dimensional model which does not require references to a higher dimensional one. We are able to model planar chiral materials starting from a geometrically non-linear Cosserat type elasticity theory. Our results are in agreement with previously derived equations of motion but can contain additional terms due to our non-linear approach. Plane wave solutions are briefly discussed within this model.
description: 22 pages, 1 figure; v2 updated version
British Gallup Poll CQ 583
Creators: name: Social Surveys (Gallup Poll) Limited
Publisher: name: Roper Center for Public Opinion Research
Year: 2022

description: Government approval (1); James Callaghan performance (1); Margaret Thatcher performance (1); Daniel Steel performance (1); party support (1); last general election (2); government spending (5); Rhodesian situation (2); Conservative party (20); voter influence (8); product advertising (26); lager habit (1); newspapers (2); television habits (1); hobbies (14); home appliances (63).