cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Twisted bilayer graphene.VI. An Exact Diagonalization Study of Twisted Bilayer Graphene at Non-Zero Integer Fillings
Creators: name: Xie, Fang
name: Cowsik, Aditya
name: Song, Zhi-Da
name: Lian, Biao
name: Bernevig, B. Andrei
name: Regnault, Nicolas
Publisher: name: arXiv
Year: 2020
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Using exact diagonalization, we study the projected Hamiltonian with Coulomb interaction in the 8 flat bands of first magic angle twisted bilayer graphene. Employing the U(4) (U(4)$\times$U(4)) symmetries in the nonchiral (chiral) flat band limit, we reduced the Hilbert space to an extent which allows for study around $ν=\pm 3,\pm2,\pm1$ fillings. In the first chiral limit $w_0/w_1=0$ where $w_0$ ($w_1$) is the $AA$ ($AB$) stacking hopping, we find that the ground-states at these fillings are extremely well-described by Slater determinants in a so-called Chern basis, and the exactly solvable charge $\pm1$ excitations found in [arXiv:2009.14200] are the lowest charge excitations up to system sizes $8\times8$ (for restricted Hilbert space) in the chiral-flat limit. We also find that the Flat Metric Condition (FMC) used in [arXiv:2009.11301,2009.11872,2009.12376,2009.13530,2009.14200] for obtaining a series of exact ground-states and excitations holds in a large parameter space. For $ν=-3$, the ground state is the spin and valley polarized Chern insulator with $ν_C=\pm1$ at $w_0/w_1\lesssim0.9$ (0.3) with (without) FMC. At $ν=-2$, we can only numerically access the valley polarized sector, and we find a spin ferromagnetic phase when $w_0/w_1\gtrsim0.5t$ where $t\in[0,1]$ is the factor of rescaling of the actual TBG bandwidth, and a spin singlet phase otherwise, confirming the perturbative calculation [arXiv:2009.13530]. The analytic FMC ground state is, however, predicted in the intervalley coherent sector which we cannot access [arXiv:2009.13530]. For $ν=-3$ with/without FMC, when $w_0/w_1$ is large, the finite-size gap $Δ$ to the neutral excitations vanishes, leading to phase transitions. Further analysis of the ground state momentum sectors at $ν=-3$ suggests a competition among (nematic) metal, momentum $M_M$ ($π$) stripe and $K_M$-CDW orders at large $w_0/w_1$.
description: 22+26 pages, 15+20 figures. Added discussion about spin polarized simulation and intervalley coherent states at $\nu=-2$ filling factor. Updated references
Discontinuity of straightening in anti-holomorphic dynamics: II
Creators: name: Inou, Hiroyuki
name: Mukherjee, Sabyasachi
Publisher: name: arXiv
Year: 2020
Subjects: subject: Dynamical Systems (math.DS)
subject: Complex Variables (math.CV)
subject: FOS: Mathematics
subject: 37F10, 37F20, 37F25, 37F46

description: In [M3], Milnor found Tricorn-like sets in the parameter space of real cubic polynomials. We give a rigorous definition of these Tricorn-like sets as suitable renormalization loci, and show that the dynamically natural straightening map from such a Tricorn-like set to the original Tricorn is discontinuous. We also prove some rigidity theorems for polynomial parabolic germs, which state that one can recover unicritical holomorphic and anti-holomorphic polynomials from their parabolic germs.
description: Same as published version. Part I is available at arXiv:1605.08061v5
Ferramenta da Terapia do Esquema (TE): Técnicas de reestruturação de padrões de pensamento rígidos
Creators: name: Brandl, Edenilson
Publisher: name: Zenodo
Year: 2024
Subjects: Ferramenta da Terapia do Esquema (TE)
Técnicas de reestruturação de padrões de pensamento rígidos
Terapia do Esquema (TE)
Enciclopédia da Conscienciologia

description: Definologia: As técnicas de reestruturação de padrões de pensamento rígidos são recursos utilizados na Terapia do Esquema (TE) para promover a flexibilização e a modificação de esquemas cognitivos disfuncionais, caracterizados por padrões de pensamento inflexíveis e mal-adaptativos.
Retrospective of the RVN Webinar Series: Year 5
Creators: name: Harvey, Andrew
Publisher: name: Zenodo
Year: 2024
Subjects: Languages of Tanzania
Tanzanian Rift Valley

description: This talk takes a look back at the fifth year of the Rift Valley Webinar Series, with the intent of comparing it with previous years, exploring common themes in Rift research and possibilities for the future. The final half of the session will feature an unrecorded discussion with attendees, collecting feedback on the Rift Valley Network, as well as suggestions for improvements and changes for the 2024/2025 year.

-Note: This talk has not gone through a process of peer review, and findings should therefore be treated as preliminary and subject to change.

-Acknowledgement and citation: Harvey, Andrew. 2024. Retrospective of the RVN Webinar Series: Year 5. Talk Given at Rift Valley Webinar Series 20/03/2024.
A One-bit, Comparison-Based Gradient Estimator
Creators: name: Cai, HanQin
name: Mckenzie, Daniel
name: Yin, Wotao
name: Zhang, Zhenliang
Publisher: name: arXiv
Year: 2020
Subjects: subject: Optimization and Control (math.OC)
subject: Artificial Intelligence (cs.AI)
subject: Machine Learning (cs.LG)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences

description: We study zeroth-order optimization for convex functions where we further assume that function evaluations are unavailable. Instead, one only has access to a $\textit{comparison oracle}$, which given two points $x$ and $y$ returns a single bit of information indicating which point has larger function value, $f(x)$ or $f(y)$. By treating the gradient as an unknown signal to be recovered, we show how one can use tools from one-bit compressed sensing to construct a robust and reliable estimator of the normalized gradient. We then propose an algorithm, coined SCOBO, that uses this estimator within a gradient descent scheme. We show that when $f(x)$ has some low dimensional structure that can be exploited, SCOBO outperforms the state-of-the-art in terms of query complexity. Our theoretical claims are verified by extensive numerical experiments.
Did a Neanderthal Make the Groove in This Stone?
Creators: name: Anderson, Mark
Publisher: name: figshare
Year: 2015
Subjects: Archaeology

description: A sandstone pebble from a surface site in the Mainz Basin exhibits an artificial groove which is wind-polished. Because in the Mainz Basin wind polish is an indicator of past periglacial conditions, the groove must be of pre-Mesolithic origin. The only other wind-polished artifacts from the site form a coherent lithic assemblage based on the Discoid method. Typologically, the assemblage can be dated to the Middle Paleolithic. Like the grooved stone, the knapped artifacts were manufactured from rounded nonflint pebbles collected from a river gravel deposit. Furthermore, the grooved stone was found at the intrasite locality which has the highest concentration of Middle Paleolithic artifacts.
Guidelines and best practices for technology-aided narratives for museums and art collections
Creators: name: Balzani, Roberto
name: Musiani, Elena
Publisher: name: Zenodo
Year: 2024

description: In this deliverable (D7), we present the approach we have developed for analysing the literature of the last few years (2019-2023), as well as the tool we have applied for analysing the literature of the last decade, according to the methodology proposed at the end of August 2023. Also, we provide an extensive description of one of the “core” case studies of the project, which we have used as a representative scenario to extract and provide the guidelines and best practices for addressing digitisation in museums as a cultural issue.
Invariant chains in algebra and discrete geometry
Creators: name: Kahle, Thomas
name: Van Le, Dinh
name: Römer, Tim
Publisher: name: arXiv
Year: 2020
Subjects: subject: Combinatorics (math.CO)
subject: Commutative Algebra (math.AC)
subject: Metric Geometry (math.MG)
subject: FOS: Mathematics
subject: 05E18, 90C05 (Primary), 13A50, 20M30, 52B15 (Secondary)

description: We relate finite generation of cones, monoids, and ideals in increasing chains (the local situation) to equivariant finite generation of the corresponding limit objects (the global situation). For cones and monoids there is no analog of Noetherianity as in the case of ideals and we demonstrate this in examples. As a remedy, we find local-global correspondences for finite generation. These results are derived from a more general framework that relates finite generation under closure operations to equivariant finite generation under general families of maps. We also give a new proof that non-saturated Inc-invariant chains of ideals stabilize, closing a gap in the literature.
description: 28 pages; revised version
Exact solutions in low-rank approximation with zeros
Creators: name: Kubjas, Kaie
name: Sodomaco, Luca
name: Tsigaridas, Elias
Publisher: name: arXiv
Year: 2020
Subjects: subject: Algebraic Geometry (math.AG)
subject: Optimization and Control (math.OC)
subject: FOS: Mathematics
subject: 14M12, 14P05, 13P25, 90C26, 68W30

description: Low-rank approximation with zeros aims to find a matrix of fixed rank and with a fixed zero pattern that minimizes the Euclidean distance to a given data matrix. We study the critical points of this optimization problem using algebraic tools. In particular, we describe special linear, affine, and determinantal relations satisfied by the critical points. We also investigate the number of critical points and how this number is related to the complexity of nonnegative matrix factorization problem.
description: revised version to appear on Linear Algebra and its Applications, 26 pages, 1 figure, 8 tables
Universal classical-quantum superposition coding and universal classical-quantum multiple access channel coding
Creators: name: Hayashi, Masahito
name: Cai, Ning
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: Information Theory (cs.IT)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: We derive universal classical-quantum superposition coding and universal classical-quantum multiple access channel code by using generalized packing lemmas for the type method. Using our classical-quantum universal superposition code, we establish the capacity region of a classical-quantum compound broadcast channel with degraded message sets. Our universal classical-quantum multiple access channel codes have two types of codes. One is a code with joint decoding and the other is a code with separate decoding. The former universally achieves corner points of the capacity region and the latter universally achieves general points of the capacity region. Combining the latter universal code with the existing result by Quantum Inf Process. 18, 246 (2019), we establish a single-letterized formula for the capacity region of a classical-quantum compound multiple access channel.
Reconfigurable Intelligent Surfaces in Action for Non-Terrestrial Networks
Creators: name: Tekbıyık, Kürşat
name: Kurt, Güneş Karabulut
name: Ekti, Ali Rıza
name: Yanikomeroglu, Halim
Publisher: name: arXiv
Year: 2020
Subjects: subject: Information Theory (cs.IT)
subject: Machine Learning (cs.LG)
subject: Signal Processing (eess.SP)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Next-generation communication technology will be made possible by cooperation between terrestrial networks with non-terrestrial networks (NTN) comprised of high-altitude platform stations and satellites. Further, as humanity embarks on the long road to establish new habitats on other planets, cooperation between NTN and deep-space networks (DSN) will be necessary. In this regard, we propose the use of reconfigurable intelligent surfaces (RIS) to improve coordination between these networks given that RIS perfectly match the size, weight, and power restrictions of operating in space. A comprehensive framework of RIS-assisted non-terrestrial and interplanetary communications is presented that pinpoints challenges, use cases, and open issues. Furthermore, the performance of RIS-assisted NTN under environmental effects such as solar scintillation and satellite drag is discussed in light of simulation results.
description: to appear in IEEE Vehicular Technology Magazine
Optimal tests for continuous-variable quantum teleportation and photodetectors
Creators: name: Sharma, Kunal
name: Sanders, Barry C.
name: Wilde, Mark M.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Quantum teleportation is a primitive in several important applications, including quantum communication, quantum computation, error correction, and quantum networks. In this work, we propose an optimal test for the performance of continuous-variable (CV) quantum teleportation in terms of the energy-constrained channel fidelity between ideal CV teleportation and its experimental implementation. Work prior to ours considered suboptimal tests of the performance of CV teleportation, focusing instead on its performance for particular states, such as ensembles of coherent states, squeezed states, cat states, etc. Here we prove that the optimal state for testing CV teleportation is an entangled superposition of twin Fock states. We establish this result by reducing the problem of estimating the energy-constrained channel fidelity between ideal CV teleportation and its experimental approximation to a quadratic program and solving it. As an additional result, we obtain an analytical solution to the energy-constrained diamond distance between a photodetector and its experimental approximation. These results are relevant for experiments that make use of CV teleportation and photodetectors.
description: v2: 17 pages, 2 figures
At the edge of a one-dimensional jellium
Creators: name: Chafaï, Djalil
name: García-Zelada, David
name: Jung, Paul
Publisher: name: arXiv
Year: 2020
Subjects: subject: Probability (math.PR)
subject: Mathematical Physics (math-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: Primary 82B05, 60K35, 60G55, Secondary 82D05, 62G30, 60G70

description: We consider a one-dimensional classical Wigner jellium, not necessarily charge neutral, for which the electrons are allowed to exist beyond the support of the background charge. The model can be seen as a one-dimensional Coulomb gas in which the external field is generated by a smeared background on an interval. It is a true one-dimensional Coulomb gas and not a one-dimensional log-gas. The system exists if and only if the total background charge is greater than the number of electrons minus one. For various backgrounds, we show convergence to point processes, at the edge of the support of the background. In particular, this provides asymptotic analysis of the fluctuations of the right-most particle. Our analysis reveals that these fluctuations are not universal, in the sense that depending on the background, the tails range anywhere from exponential to Gaussian-like behavior, including for instance Tracy-Widom-like behavior. We also obtain a Renyi-type probabilistic representation for the order statistics of the particle system beyond the support of the background.
description: 20 pages, this is a shorter version which puts more focus on our main results
SPAA: Stealthy Projector-based Adversarial Attacks on Deep Image Classifiers
Creators: name: Huang, Bingyao
name: Ling, Haibin
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Light-based adversarial attacks use spatial augmented reality (SAR) techniques to fool image classifiers by altering the physical light condition with a controllable light source, e.g., a projector. Compared with physical attacks that place hand-crafted adversarial objects, projector-based ones obviate modifying the physical entities, and can be performed transiently and dynamically by altering the projection pattern. However, subtle light perturbations are insufficient to fool image classifiers, due to the complex environment and project-and-capture process. Thus, existing approaches focus on projecting clearly perceptible adversarial patterns, while the more interesting yet challenging goal, stealthy projector-based attack, remains open. In this paper, for the first time, we formulate this problem as an end-to-end differentiable process and propose a Stealthy Projector-based Adversarial Attack (SPAA) solution. In SPAA, we approximate the real Project-and-Capture process using a deep neural network named PCNet, then we include PCNet in the optimization of projector-based attacks such that the generated adversarial projection is physically plausible. Finally, to generate both robust and stealthy adversarial projections, we propose an algorithm that uses minimum perturbation and adversarial confidence thresholds to alternate between the adversarial loss and stealthiness loss optimization. Our experimental evaluations show that SPAA clearly outperforms other methods by achieving higher attack success rates and meanwhile being stealthier, for both targeted and untargeted attacks.
Note on higher-point correlation functions of the $T\bar{T}$ or $J\bar{T}$ deformed CFTs
Creators: name: He, Song
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We investigate generic n-point correlation functions of conformal field theories (CFTs), with $T\bar{T}$ and $J\bar{T}$ deformations, in terms of the perturbative CFT approach. We systematically obtain the first order correction to the generic correlation functions of CFTs with $T\bar{T}$ or $J\bar{T}$ deformation. We compute the out-of-time ordered correlation function (OTOC) in the Ising model with $T\bar{T}$ or $J\bar{T}$ deformation, which confirms that these deformations do not change the integrable property up to the first order level.
description: 34 pages
Weak formulations of the nonlinear Poisson-Boltzmann equation in biomolecular electrostatics
Creators: name: Iglesias, José A.
name: Nakov, Svetoslav
Publisher: name: arXiv
Year: 2020
Subjects: subject: Analysis of PDEs (math.AP)
subject: Biological Physics (physics.bio-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: 35J61, 35D30, 35R06, 92C05

description: We consider the nonlinear Poisson-Boltzmann equation in the context of electrostatic models for a biological macromolecule, embedded in a bounded domain containing a solution of an arbitrary number of ionic species which is not necessarily charge neutral. The resulting semilinear elliptic equation combines several difficulties: exponential growth and lack of sign preservation in the nonlinearity accounting for ion mobility, measure data arising from point charges inside the molecule, and discontinuous permittivities across the molecule boundary. Exploiting the modelling assumption that the point sources and the nonlinearity are active on disjoint parts of the domain, one can use a linear decomposition of the potential into regular and singular components. A variational argument can be used for the regular part, but the unbounded nonlinearity makes the corresponding functional not differentiable in Sobolev spaces. By proving boundedness of minimizers, these are related to standard $H^1$ weak formulations for the regular component and in the framework of Boccardo and Gallouët for the full potential. Finally, a result of uniqueness of this type of weak solutions for more general semilinear problems with measure data validates the strategy, since the different decompositions and test spaces considered must then lead to the same solution.
description: 36 pages, 2 figures
Data-Driven Dispatchable Regions with Potentially Active Boundaries for Renewable Power Generation: Concept and Construction
Creators: name: Liu, Yanqi
name: Li, Zhigang
name: Wei, Wei
name: Zheng, Jiehui
name: Zhang, Hongcai
Publisher: name: arXiv
Year: 2020
Subjects: subject: Systems and Control (eess.SY)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: The dispatchable region of volatile renewable power generation (RPG) quantifies how much uncertainty the power system can handle at a given operating point. State-of-the-art dispatchable region (DR) research has studied how system operational constraints influence the DR but has seldom considered the effect of the uncertainty features of RPG outputs. The traditional DR is generally described by a large number of boundaries, and it is computationally intensive to construct. To bridge these gaps, a novel type of DR is defined, which is enclosed by potentially active boundaries (PABs) that consider the operational constraints and uncertainty features of RPG outputs. The proposed DR is easier to construct because the PABs are only a small part of the traditional DR boundaries. The procedure for constructing the proposed DR is described in terms of the progressive search for PABs, which is formulated as a mixed-integer linear program by incorporating the discrete observed data points of RPG outputs as an approximate distribution. A parallel solution paradigm is also developed to expedite the construction procedure when using a large observed dataset. Simulation tests on the IEEE 30-bus and 118-bus systems verify the effectiveness and scalability of the proposed DR and the efficiency of the proposed algorithm.
Eliminating Reflections in Waveguide Bends Using a Metagrating-Inspired Semianalytical Methodology
Creators: name: Biniashvili, Liran
name: Epstein, Ariel
Publisher: name: arXiv
Year: 2020
Subjects: subject: Applied Physics (physics.app-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We present a semianalytical method to obtain perfect transmission across abrupt H-plane bends in single-mode rectangular waveguides using a single passive polarizable element (scatterer). The underlying analysis and synthesis schemes are inspired by the rapidly-growing research on metagratings, typically used to manipulate wave trajectories in free-space. These sparse configurations of subwavelength polarizable particles (meta-atoms) are designed by careful tailoring of inter-element near-field and far-field interactions, relying on analytical models to resolve the required meta-atom distribution and geometry to facilitate a desired interference pattern when excited by the incident wave. Utilizing these metagrating design concepts, we develop a modal formalism for obtaining a collection of locations inside the bend junction, in which a passive scatterer may be placed to zero out the return loss. Subsequently, we propose two different shapes for the scatterer and discuss, for each of them, the ways in which their geometrical characteristics may be retrieved. This versatile and efficient methodology, verified via full-wave simulations, can be utilized to eliminate reflection loss in diverse bend configurations, often found in complex wave-guiding systems used for antenna feeding and power transmission. Moreover, these results demonstrate the usefulness and potential of metagrating design concepts for various applications, beyond free-space beam manipulation.
description: 16 pages, 9 figures
Using the stress function in the flow of generalized Newtonian fluids through conduits with non-circular or multiply connected cross sections
Creators: name: Sochi, Taha
Publisher: name: figshare
Year: 2015
Subjects: Applied Physics

description: We investigate the possibility that the spatial dependency of stress in generalized Newtonian flow systems is a function of the applied pressure field and the conduit geometry but not of the fluid rheology. This possibility is well established for the case of a one-dimensional flow through simply connected regions, specifically tubes of circular uniform cross sections and plane thin slits. If it can also be established for the more general case of generalized Newtonian flow through non-circular or multiply connected geometries, such as the two-dimensional flow through conduits of rectangular or elliptical cross sections or the flow through annular circular pipes, then analytical or semi-analytical or highly accurate numerical solutions; regarding stress, rate of strain, velocity profile and volumetric flow rate; for these geometries can be obtained from the stress function, which can be easily obtained from the Newtonian case, in combination with the constitutive rheological relation for the particular non-Newtonian fluid, as done previously for the case of the one-dimensional flow through simply connected regions.
Linear and nonlinear optical properties in spherical quantum dots: Inversely quadratic Hellmann potential
Creators: name: Máthé, L.
name: Onyenegecha, C. P.
name: Farcaş, A. -A.
name: Pioraş-Ţimbolmaş, L. -M.
name: Solaimani, M.
name: Hassanabadi, H.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The aims of the reported work are to provide new insights into the quantum dot optical properties confined in an inverse of a quadratic Hellmann potential. The Schrödinger equation is solved using the Nikiforov-Uvarov (NU) method, in order to obtain the analytical expressions of the eigenenergies and the eigenfunctions. The linear together with the third-order nonlinear changes in absorption coefficients and refractive index are investigated using the density matrix formalism. The absorption coefficients and the refractive index changes are strong related to the structure parameters and the optical intensity.
description: 8 figures
Space Information Time Theory: Negative Information Black Holes
Creators: name: Kitchen, Kris
Publisher: name: figshare
Year: 2015
Subjects: subject: Interstellar and Intergalactic Matter
subject: Instrumentation, Techniques, and Astronomical Observations
subject: 20104 Galactic Astronomy
subject: FOS: Physical sciences
subject: Cosmology
subject: Planetary Geology
subject: Stellar Astronomy
subject: Stars, Variable Stars
subject: Astrophysics
subject: Planetary Science
subject: Solar System, Solar Physics, Planets and Exoplanets
subject: Extragalactic Astronomy
subject: Space Science

description: Space Information Time Theory: Negative Information Black Holes
Scaling Up Bayesian Uncertainty Quantification for Inverse Problems using Deep Neural Networks
Creators: name: Lan, Shiwei
name: Li, Shuyi
name: Shahbaba, Babak
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computation (stat.CO)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: Due to the importance of uncertainty quantification (UQ), Bayesian approach to inverse problems has recently gained popularity in applied mathematics, physics, and engineering. However, traditional Bayesian inference methods based on Markov Chain Monte Carlo (MCMC) tend to be computationally intensive and inefficient for such high dimensional problems. To address this issue, several methods based on surrogate models have been proposed to speed up the inference process. More specifically, the calibration-emulation-sampling (CES) scheme has been proven to be successful in large dimensional UQ problems. In this work, we propose a novel CES approach for Bayesian inference based on deep neural network models for the emulation phase. The resulting algorithm is computationally more efficient and more robust against variations in the training set. Further, by using an autoencoder (AE) for dimension reduction, we have been able to speed up our Bayesian inference method up to three orders of magnitude. Overall, our method, henceforth called \emph{Dimension-Reduced Emulative Autoencoder Monte Carlo (DREAMC)} algorithm, is able to scale Bayesian UQ up to thousands of dimensions for inverse problems. Using two low-dimensional (linear and nonlinear) inverse problems we illustrate the validity of this approach. Next, we apply our method to two high-dimensional numerical examples (elliptic and advection-diffussion) to demonstrate its computational advantages over existing algorithms.
description: 38 pages, 20 figures, to appear in JUQ
Stochastic integrals and Brownian motion on abstract nilpotent Lie groups
Creators: name: Melcher, Tai
Publisher: name: arXiv
Year: 2021
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: Primary 60J65 28D05, Secondary 58J65 22E65

description: We construct a class of iterated stochastic integrals with respect to Brownian motion on an abstract Wiener space which allows for the definition of Brownian motions on a general class of infinite-dimensional nilpotent Lie groups based on abstract Wiener spaces. We then prove that a Cameron--Martin type quasi-invariance result holds for the associated heat kernel measures in the non-degenerate case, and give estimates on the associated Radon--Nikodym derivative. We also prove that a log Sobolev estimate holds in this setting.
The Cognitive Spectrum of Transformative Learning
Creators: name: Dix, Michael
Publisher: name: Swinburne
Year: 2024

description: Although different transformative learning theories have been described in the literature, a detailed integrative theory is yet to emerge. I argue that unduly intellectualist assumptions regarding cognition have hampered current understandings and have obscured transformative learning's cognitive and metacognitive essence. Firstly, Mezirow's implied restriction of his Socratic/Habermasian model to discursive rationality unnecessarily excludes transformative learning accomplished through enactive, non-discursive modes of cognition, metacognition, and rationality. Likewise, a narrow conception of cognition prevents theorists of depth transformation from recognising the essential cognitive roles at depth of metaphors deriving from embodied experience and their rational elaboration at depth through metaphoric implication. In the light of current theory, I reconsider J.H. Newman's nineteenth-century insights regarding notional-to-real transformation, showing how a deeper and more comprehensive understanding of cognition and metacognition reveals transformative learning's essential cognitive and metacognitive dynamic, in confirmation of Kegan's "subject-object" model and Mezirow's stress on the importance of metacognition.
High-throughput fast full-color digital pathology based on Fourier ptychographic microscopy via color transfer
Creators: name: Gao, Yuting
name: Chen, Jiurun
name: Wang, Aiye
name: Pan, An
name: Ma, Caiwen
name: Yao, Baoli
Publisher: name: arXiv
Year: 2021
Subjects: subject: Image and Video Processing (eess.IV)
subject: Medical Physics (physics.med-ph)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Physical sciences

description: Full-color imaging is significant in digital pathology. Compared with a grayscale image or a pseudo-color image that only contains the contrast information, it can identify and detect the target object better with color texture information. Fourier ptychographic microscopy (FPM) is a high-throughput computational imaging technique that breaks the tradeoff between high resolution (HR) and large field-of-view (FOV), which eliminates the artifacts of scanning and stitching in digital pathology and improves its imaging efficiency. However, the conventional full-color digital pathology based on FPM is still time-consuming due to the repeated experiments with tri-wavelengths. A color transfer FPM approach, termed CFPM was reported. The color texture information of a low resolution (LR) full-color pathologic image is directly transferred to the HR grayscale FPM image captured by only a single wavelength. The color space of FPM based on the standard CIE-XYZ color model and display based on the standard RGB (sRGB) color space were established. Different FPM colorization schemes were analyzed and compared with thirty different biological samples. The average root-mean-square error (RMSE) of the conventional method and CFPM compared with the ground truth is 5.3% and 5.7%, respectively. Therefore, the acquisition time is significantly reduced by 2/3 with the sacrifice of precision of only 0.4%. And CFPM method is also compatible with advanced fast FPM approaches to reduce computation time further.
description: 24 pages, 8 figures
Fusion of Majorana Bound States with Mini-Gate Control in Two-Dimensional Systems
Creators: name: Zhou, Tong
name: Dartiailh, Matthieu C.
name: Sardashti, Kasra
name: Han, Jong E.
name: Matos-Abiague, Alex
name: Shabani, Javad
name: Zutic, Igor
Publisher: name: arXiv
Year: 2021
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: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: A hallmark of topological superconductivity is the non-Abelian statistics of Majorana bound states (MBS), its chargeless zero-energy emergent quasiparticles. The resulting fractionalization of a single electron, stored nonlocally as a two spatially-separated MBS, provides a powerful platform for implementing fault-tolerant topological quantum computing. However, despite intensive efforts, experimental support for MBS remains indirect and does not probe their non-Abelian statistics. Here we propose how to overcome this obstacle in mini-gate controlled planar Josephson junctions (JJs) and demonstrate non-Abelian statistics through MBS fusion, detected by charge sensing using a quantum point contact, based on dynamical simulations. The feasibility of preparing, manipulating, and fusing MBS in two-dimensional (2D) systems is supported in our experiments which demonstrate the gate control of topological transition and superconducting properties with five mini gates in InAs/Al-based JJs. While we focus on this well-established platform, where the topological superconductivity was already experimentally detected, our proposal to identify elusive non-Abelian statistics motivates also further MBS studies in other gate-controlled 2D systems.
description: 10 pages, 7 figures; Accepted in Nature Communications
Fast Facial Landmark Detection and Applications: A Survey
Creators: name: Khabarlak, Kostiantyn
name: Koriashkina, Larysa
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Dense facial landmark detection is one of the key elements of face processing pipeline. It is used in virtual face reenactment, emotion recognition, driver status tracking, etc. Early approaches were suitable for facial landmark detection in controlled environments only, which is clearly insufficient. Neural networks have shown an astonishing qualitative improvement for in-the-wild face landmark detection problem, and are now being studied by many researchers in the field. Numerous bright ideas are proposed, often complimentary to each other. However, exploration of the whole volume of novel approaches is quite challenging. Therefore, we present this survey, where we summarize state-of-the-art algorithms into categories, provide a comparison of recently introduced in-the-wild datasets (e.g., 300W, AFLW, COFW, WFLW) that contain images with large pose, face occlusion, taken in unconstrained conditions. In addition to quality, applications require fast inference, and preferably on mobile devices. Hence, we include information about algorithm inference speed both on desktop and mobile hardware, which is rarely studied. Importantly, we highlight problems of algorithms, their applications, vulnerabilities, and briefly touch on established methods. We hope that the reader will find many novel ideas, will see how the algorithms are used in applications, which will enable further research.
Piecewise Non-Linearity and Capacitance in the Joint Density Functional Theory of Extended Interfaces
Creators: name: Binninger, Tobias
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The ab initio simulation of charged interfaces in the framework of density functional theory (DFT) is heavily employed for the study of electrochemical energy conversion processes. The capacitance is the primary descriptor for the response of the electrochemical interface. It is essentially equal to the inverse of the energy curvature as a function of electron number, and as such there appears a conflict with the fundamental principle of piecewise linearity in DFT that requires the energy curvature to be zero at fractional electron numbers, i.e. almost everywhere. To resolve this conflict, we derive an exact expression between the energy curvature and the Kohn-Sham density of states, the local density of states, and the Fukui potential. We find that the piecewise linearity requirement does not hold for the volume- or area-specific energy of extended systems and surfaces. Applied to the joint density functional theory of an electrode-electrolyte interface, including the ionic and dielectric response of the electrolyte, the same expression represents a rigorous basis for the partitioning of the total interfacial capacitance into contributions of the quantum capacitance, space-charge capacitance, and electrochemical double-layer capacitance. It provides insight into the influence of the electrode material, thickness, and temperature on the charging characteristics, as demonstrated by results for a bulk gold electrode, a single-layer gold electrode, and a single-layer graphene electrode.
Book Review : "Operation Linda Nchi" - Kenya's Military Experience in Somalia by KDF/MoD Kenya
Creators: name: Nyagudi, Nyagudi Musandu
Publisher: name: figshare
Year: 2015
Subjects: subject: Education
subject: Law
subject: FOS: Law
subject: History
subject: Sociology
subject: FOS: Sociology
subject: Anthropology

description: Review on Kenya Defence Forces book about operations in Somalia.
5GCity Virtualization Infrastructure Interim Release (D3.2)
Creators: name: Sechkova, Teodora
name: Paolino, Michele
name: Kraja, Elian
name: Agueci, Leonardo
name: Carrozzo, Gino
name: Garcia, Antonio
name: Moore, Trevor
name: Betzler, August
name: Meixner, Carlos Colman
name: Huici, Felipe
name: Diogo, Pedro
name: Colom, Jordi
Publisher: name: Zenodo
Year: 2019

description: This deliverable presents the interim release of the implementation of the MEC node for resource-constrained devices, and network virtualization. It will include the release of the VNFs.
Note on a less ad hoc derivation of the second quantization formalism
Creators: name: Wu, Ning
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Second quantization is an essential topic in senior undergraduate and postgraduate level Quantum Mechanics course. However, it seems that there is a lack of transparent and natural derivation of this formalism from the first-quantization one in most existing textbooks. Without introducing the concept of a simple harmonic oscillator and taking the case of an assembly of identical fermions as an example, we provide a less ad hoc derivation of the second quantization formalism based on the equivalence of the fully antisymmetric many-fermion states and the Fock states.
description: 9 pages, 0 figures. A slightly modified Chinese version was published in College Physics
STDP Pattern Onset Learning Depends on Background Activity
Creators: name: Humble, James
name: Furber, Steve
name: Denham, Sue
name: Wennekers, Thomas
Publisher: name: figshare
Year: 2016
Subjects: subject: 60102 Bioinformatics
subject: FOS: Computer and information sciences
subject: Neuroscience

description: Spike-timing dependent plasticity is a learning mechanism used extensively within neural modelling. The learning rule has been shown to allow a neuron to find the beginning of a repeated spatio-temporal pattern among its afferents. In this study we adduce that such learning is dependent on background activity, and is un-stable when in a noisy framework. We also present insights into the neuron’s encoding.
What does STDP learn?
Creators: name: Humble, James
Publisher: name: figshare
Year: 2016
Subjects: subject: Computational Biology
subject: 60102 Bioinformatics
subject: FOS: Computer and information sciences
subject: Neuroscience

description: Spike-timing dependent plasticity is a learning mechanism used extensively within neural mod-
elling. The learning rule has been shown to allow a neuron to find the onset of a spatio-temporal
pattern repeated among its afferents. In this study we attempt to answer the question, what does
this neuron learn? With a spiking neuron model and a reverse correlation method, we adduce that
the neuron learns two components: (1) the level of background activity and (2) specific spike times
of the pattern. We further construct a mathematical framework which combines the two components
and can explain the neuron’s response under different experimental conditions. This report is uncorrected and extends previous results. For a corrected version see my PhD thesis. These results are not going to be published in the future and are included here only for reference.
Exploring Scale-Measures of Data Sets
Creators: name: Hanika, Tom
name: Hirth, Johannes
Publisher: name: arXiv
Year: 2021
Subjects: subject: Artificial Intelligence (cs.AI)
subject: Machine Learning (cs.LG)
subject: Logic in Computer Science (cs.LO)
subject: FOS: Computer and information sciences
subject: F.4.1; I.2.6
subject: 03G10, 68T27, 68T30, 06B10, 06A15, 06-08

description: Measurement is a fundamental building block of numerous scientific models and their creation. This is in particular true for data driven science. Due to the high complexity and size of modern data sets, the necessity for the development of understandable and efficient scaling methods is at hand. A profound theory for scaling data is scale-measures, as developed in the field of formal concept analysis. Recent developments indicate that the set of all scale-measures for a given data set constitutes a lattice and does hence allow efficient exploring algorithms. In this work we study the properties of said lattice and propose a novel scale-measure exploration algorithm that is based on the well-known and proven attribute exploration approach. Our results motivate multiple applications in scale recommendation, most prominently (semi-)automatic scaling.
description: 16 pages, 5 figures
Growth Functions, Rates and Classes of String-Based Multiway Systems
Creators: name: Zeschke, Yorick
Publisher: name: arXiv
Year: 2021
Subjects: subject: Discrete Mathematics (cs.DM)
subject: FOS: Computer and information sciences

description: In context of the Wolfram Physics Project, a certain class of abstract rewrite systems known as "multiway systems" have played an important role in discrete models of spacetime and quantum mechanics. However, as abstract mathematical entities, these rewrite systems are interesting in their own right. This paper undertakes the effort to establish computational properties of multiway systems. Specifically, we investigate growth rates and growth classes of string-based multiway systems. After introducing the concepts of "growth functions", "growth rates" and "growth classes" to quantify a system's state-space growth over "time" (successive steps of evolution) on different levels of precision, we use them to show that multiway systems can, in a specific sense, grow slower than all computable functions while never exceeding the growth rate of exponential functions. In addition, we start developing a classification scheme for multiway systems based on their growth class. Furthermore, we find that multiway growth functions are not trivially regular but instead "computationally diverse", meaning that they are capable of computing or approximating various commonly encountered mathematical functions. We discuss several implications of these properties as well as their physical relevance. Apart from that, we present and exemplify methods for explicitly constructing multiway systems to yield desired growth functions.
description: 27 pages, 13 figures
DEFT: Distilling Entangled Factors by Preventing Information Diffusion
Creators: name: Wu, Jiantao
name: Wang, Lin
name: Yang, Bo
name: Li, Fanqi
name: Liu, Chunxiuzi
name: Zhou, Jin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Machine Learning (cs.LG)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: Disentanglement is a highly desirable property of representation owing to its similarity to human understanding and reasoning. Many works achieve disentanglement upon information bottlenecks (IB). Despite their elegant mathematical foundations, the IB branch usually exhibits lower performance. In order to provide an insight into the problem, we develop an annealing test to calculate the information freezing point (IFP), which is a transition state to freeze information into the latent variables. We also explore these clues or inductive biases for separating the entangled factors according to the differences in the IFP distributions. We found the existing approaches suffer from the information diffusion problem, according to which the increased information diffuses in all latent variables. Based on this insight, we propose a novel disentanglement framework, termed the distilling entangled factor (DEFT), to address the information diffusion problem by scaling backward information. DEFT applies a multistage training strategy, including multigroup encoders with different learning rates and piecewise disentanglement pressure, to disentangle the factors stage by stage. We evaluate DEFT on three variants of dSprite and SmallNORB, which show low-variance and high-level disentanglement scores. Furthermore, the experiment under the correlative factors shows incapable of TC-based approaches. DEFT also exhibits a competitive performance in the unsupervised setting.
Certifiably Robust Variational Autoencoders
Creators: name: Barrett, Ben
name: Camuto, Alexander
name: Willetts, Matthew
name: Rainforth, Tom
Publisher: name: arXiv
Year: 2021
Subjects: subject: Machine Learning (stat.ML)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: We introduce an approach for training Variational Autoencoders (VAEs) that are certifiably robust to adversarial attack. Specifically, we first derive actionable bounds on the minimal size of an input perturbation required to change a VAE's reconstruction by more than an allowed amount, with these bounds depending on certain key parameters such as the Lipschitz constants of the encoder and decoder. We then show how these parameters can be controlled, thereby providing a mechanism to ensure \textit{a priori} that a VAE will attain a desired level of robustness. Moreover, we extend this to a complete practical approach for training such VAEs to ensure our criteria are met. Critically, our method allows one to specify a desired level of robustness \emph{upfront} and then train a VAE that is guaranteed to achieve this robustness. We further demonstrate that these Lipschitz--constrained VAEs are more robust to attack than standard VAEs in practice.
description: 12 pages and appendix