cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Beam Cleaning and Collimation Systems
Creators: name: Redaelli, S.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Accelerator Physics (physics.acc-ph)
subject: FOS: Physical sciences

description: Collimation systems in particle accelerators are designed to dispose of unavoidable losses safely and efficiently during beam operation. Different roles are required for different types of accelerator. The present state of the art in beam collimation is exemplified in high-intensity, high-energy superconducting hadron colliders, like the CERN Large Hadron Collider (LHC), where stored beam energies reach levels up to several orders of magnitude higher than the tiny energies required to quench cold magnets. Collimation systems are essential systems for the daily operation of these modern machines. In this document, the design of a multistage collimation system is reviewed, taking the LHC as an example case study. In this case, unprecedented cleaning performance has been achieved, together with a system complexity comparable to no other accelerator. Aspects related to collimator design and operational challenges of large collimation systems are also addressed.
description: 35 pages, contribution to the 2014 Joint International Accelerator School: Beam Loss and Accelerator Protection, Newport Beach, CA, USA , 5-14 Nov 2014
Relaxation shortcuts through boundary coupling
Creators: name: Teza, Gianluca
name: Yaacoby, Ran
name: Raz, Oren
Publisher: name: arXiv
Year: 2021
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: When a hot system cools down faster than an equivalent cold one, it exhibits the Mpemba Effect. This counterintuitive phenomenon was observed in several systems including water, magnetic alloys and polymers. In most experiments the system is coupled to the bath through its boundaries, but all theories so far assumed bulk coupling. Here we build a general framework for boundary coupling relaxation and show that the Mpemba effect persists in these cases. Surprisingly, it can survive even an arbitrarily weak couplings. An example is given in the Ising antiferromagnetic chain.
Environment-assisted invariance does not necessitate Born's rule for quantum measurement
Creators: name: Mertens, Lotte
name: van Wezel, Jasper
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The argument of environment-assisted invariance (known as envariance) implying Born's rule is widely used in models for quantum measurement to reason that they must yield the correct statistics, specifically for linear models. However, it has recently been shown that linear collapse models can never give rise to Born's rule. Here, we address this apparent contradiction and point out an inconsistency in the assumptions underlying the arguments based on envariance. We use a construction in which the role of the measurement machine is made explicit and show that the presence of envariance does not imply every measurement will behave according to Born's rule. Rather, it implies that every quantum state allows a measurement machine to be constructed, which yields Born's rule when measuring that particular state. This resolves the paradox and is in agreement with the recent result of objective collapse models necessarily being non-linear.
Professionalisierung und Disziplinierung:
Creators: name: Harders, Levke
Publisher: name: Leipziger Universitätsverlag
Year: 2015

description: The institutionalization of American Studies as an interdisciplinary academic field was a reaction to a specific academic and social context within the United States. The American Studies Association (ASA) was founded in 1951 and emerged as an essential component in the professionalization of the discipline because of three relevant factors: The academic society was based on existing networks. Moreover, it secured financial resources through its popularization and higher education politics to establish an effectively running organization. But this process of shaping and normalizing the discipline finally led to exclusions whereby non-academic American Studies scholars, women and African-Americans were defined as marginal to the discipline. The consequences of this professionalization influenced American Studies and the ASA up to the 1970s
description: Comparativ, Vol 25 No 1 (2015): Der deutsche Historikerverband im interdisziplinären Vergleich
Signal background interference effects in heavy scalar production and decay to a top-anti-top pair
Creators: name: Hespel, B.
name: Maltoni, F.
name: Vryonidou, E.
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We analyse the production of a top quark pair through a heavy scalar at the LHC. We first review the main features of the signal as well as the interference with the top-anti-top background at leading order in QCD. We then study higher order QCD effects. While the background and the signal can be obtained at NNLO and NLO in QCD respectively, that is not the case for their interference, which is currently known only at LO. In order to improve the accuracy of the prediction for the interference term, we consider the effects of extra QCD radiation, i.e. the $2 \to 3$ (loop-induced) processes and obtain an estimate of the NLO corrections. As a result, we find that the contribution of the interference is important both at the total cross-section level and, most importantly, for the line-shape of the heavy scalar. In particular for resonances with widths larger than a couple of percent of the resonance mass, the interference term distorts the invariant mass distribution and generically leads to a non-trivial peak-dip structure. We study this process in a simplified model involving an additional scalar or pseudoscalar resonance as well as in the Two-Higgs-Doublet-Model for a set of representative benchmarks. We present the constraints on simplified models featuring an extra scalar as set by the LHC searches for top-anti-top resonances, and the implications of the 750 GeV diphoton excess recently reported by CMS and ATLAS for the top pair production assuming a scalar or a pseudoscalar resonance.
description: 30 pages, 17 figures
Der Deutsche Germanistenverband –
Creators: name: Richter, Myriam Isabell
name: Müller, Hans-Harald
Publisher: name: Leipziger Universitätsverlag
Year: 2015

description: Deutscher Germanistenverband: An Academic Association in a Conflict of Objectives From its inauguration in 1912 until 1933 the DGV resembled an ideological society successfully pursuing anti-modern nationalistic goals in the area of educational and school policy with modern methods. At best, it might be said to have only marginally fulfilled the role of an academic association for the field of study. While it did not actively seek to join the National Socialist movement, it did not resist it either. Only since its annually held conference in966 has the DGV started to deal with its past and subsequently reformed the association’s activities rigorously to become a modern academic association. What remains problematic today, is the fact that the DGV represents both the interests of German scholars from higher education and those of school teachers of German – which in fact frequently diverge from each other – and therefore, due to internal differentiation, is in danger of being reduced to being an umbrella association.
description: Comparativ, Vol 25 No 1 (2015): Der deutsche Historikerverband im interdisziplinären Vergleich
On real structured controllability/stabilizability/stability radius: Complexity and unified rank-relaxation based methods
Creators: name: Zhang, Yuan
name: Xia, Yuanqing
name: Zhan, Yufeng
Publisher: name: arXiv
Year: 2022
Subjects: subject: Systems and Control (eess.SY)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: This paper addresses the real structured controllability, stabilizability, and stability radii (RSCR, RSSZR, and RSSR, respectively) of linear systems, which involve determining the distance (in terms of matrix norms) between a (possibly large-scale) system and its nearest uncontrollable, unstabilizable, and unstable systems, respectively, with a prescribed affine structure. This paper makes two main contributions. First, by demonstrating that determining the feasibilities of RSCR and RSSZR is NP-hard when the perturbations have a general affine parameterization, we prove that computing these radii is NP-hard. Additionally, we prove the NP-hardness of a problem related to the RSSR. These hardness results are independent of the matrix norm used. Second, we develop unified rank-relaxation based algorithms for these problems, which can handle both the Frobenius norm and the $2$-norm based problems and share the same framework for the RSCR, RSSZR, and RSSR problems. These algorithms utilize the low-rank structure of the original problems and relax the corresponding rank constraints with a regularized truncated nuclear norm term. Moreover, a modified version of these algorithms can find local optima with performance specifications on the perturbations, under appropriate conditions. Finally, simulations suggest that the proposed methods, despite being in a simple framework, can find local optima as good as several existing methods.
description: To appear in System & Control Letters
Spin wave surface states in one-dimensional planar magnonic crystals
Creators: name: Rychły, Justyna
name: Kłos, Jarosław Wojciech
Publisher: name: arXiv
Year: 2016
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We have investigated surface spin wave states in one-dimensional planar bi-component magnonic crystals, localized on the surfaces resulting from the breaking of the periodic structure. The two systems have been considered: the magnonic crystal with periodic changes of the anisotropy field in exchange regime and the magnonic crystal composed of Fe and Ni stripes in dipolar regime with exchange interactions included. We chose the symmetric unit cell for both systems to implement the symmetry related criteria for existence of the surface states. We investigated also the surface states induced by the presence of perturbation of the surface areas of the magnonic crystals. We showed, that the system with modulated anisotropy is a direct analog of the electronic crystal. Therefore, the surface states in both systems have the same properties. For surface states existing in magnonic crystals in dipolar regime we demonstrated that spin waves preserve distinct differences to the electronic crystals, which are due to long-range dynamic dipolar interactions. We found that tuning of the strength of magnetization pinning resulting from the surface anisotropy or dipolar effect is vitally important for existence of the surface states in magnonic crystals.
Wissen und Organisation:
Creators: name: Dörk, Uwe
name: Borggräfe, Henning
Publisher: name: Leipziger Universitätsverlag
Year: 2015

description: This contribution reconstructs the histories of the two scientific disciplines Sociology and History. Drawing on their national professional associations, the authors explore the processes of academic institutionalization in both cases, though putting emphasis on the German Sociological Association (DGS). The authors identify significant differences between the histories of the DGS and the German Historical Association (VHD), which have had mayor impact on their organizational forms and functions. The institutionalization of history started already with the Enlightenment and limited the functions of the VHD mostly to the organization of annual conferences. Sociology, in contrast, was – although embedded in transnational and interdisciplinary networks – still not academically established in the German Empire. The DGS, therefore, had to assume a wide range of tasks. In their further development the profiles of both academic associations have become more equal in some aspects while perpetuating the differences in others.
description: Comparativ, Vol 25 No 1 (2015): Der deutsche Historikerverband im interdisziplinären Vergleich
Policies and strategies for records management programs : a case study of Makerere University, Uganda
Creators: name: Luyoma, David.
Publisher: name: Monash University
Year: 2022

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Flat spectrum radio quasars and BL Lacs dominate the anisotropy of the unresolved gamma-ray background
Creators: name: Korsmeier, Michael
name: Pinetti, Elena
name: Negro, Michela
name: Regis, Marco
name: Fornengo, Nicolao
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We analyze the angular power spectrum (APS) of the unresolved gamma-ray background (UGRB) emission and combine it with the measured properties of the resolved gamma-ray sources of the Fermi-LAT 4FGL catalog. Our goals are to dissect the composition of the gamma-ray sky and to establish the relevance of different classes of source populations of active galactic nuclei in determining the observed size of the UGRB anisotropy, especially at low energies. We find that, under physical assumptions for the spectral energy dispersion, i.e. by using the 4FGL catalog data as a prior, two populations are required to fit APS data, namely flat spectrum radio quasars (FSRQs) at low energies and BL Lacs (BLLs) at higher energies. The inferred luminosity functions agree well with the extrapolation of the FSRQ and BLL ones obtained from the 4FLG catalog. We use these luminosity functions to calculate the UGRB intensity from blazars, finding a contribution of 20% at 1GeV and 30% above 10 GeV. Finally, bounds on an additional gamma-ray emission due to annihilating dark matter are derived.
description: 23 pages, 13 figures, v2: updated to the published version, results are unchanged
Der Fachverband der Historiker und sein historischer Ort.
Creators: name: Berg, Matthias
name: Sabrow, Martin
Publisher: name: Leipziger Universitätsverlag
Year: 2015

description: The history of the German Historical Association is to evaluate and to write appropriate only in comparison with other scientific associations and academic cultures. This issue is dedicated to this transdisciplinary comparison of scientific associations and presents essays on the development of the German Sociological Association (Deutsche Gesellschaft für Soziologie), the German Association of German Studies (Deutscher Germanistenverband) and the American Studies Association.
description: Comparativ, Vol 25 No 1 (2015): Der deutsche Historikerverband im interdisziplinären Vergleich
Hyperbolic band topology with non-trivial second Chern numbers
Creators: name: Zhang, Weixuan
name: Di, Fengxiao
name: Zheng, Xingen
name: Sun, Houjun
name: Zhang, Xiangdong
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Topological band theory establishes a standardized framework for classifying different types of topological matters. Recent investigations have shown that hyperbolic lattices in non-Euclidean space can also be characterized by hyperbolic Bloch theorem. This theory promotes the investigation of hyperbolic band topology, where hyperbolic topological band insulators protected by first Chern numbers have been proposed. Here, we report a new finding on the construction of hyperbolic topological band insulators with a vanished first Chern number but a non-trivial second Chern number. Our model possesses the non-abelian translational symmetry of {8,8} hyperbolic tiling. By engineering intercell couplings and onsite potentials of sublattices in each unit cell, the non-trivial bandgaps with quantized second Chern numbers can appear. In experiments, we fabricate two types of finite hyperbolic circuit networks with periodic boundary conditions and partially open boundary conditions to detect hyperbolic topological band insulators. Our work suggests a new way to engineer hyperbolic topological states with higher-order topological invariants.
Fully Adaptive Bayesian Algorithm for Data Analysis, FABADA
Creators: name: Sanchez-Alarcon, Pablo M
name: Sequeiros, Yago Ascasibar
Publisher: name: arXiv
Year: 2022
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: The aim of this paper is to describe a novel non-parametric noise reduction technique from the point of view of Bayesian inference that may automatically improve the signal-to-noise ratio of one- and two-dimensional data, such as e.g. astronomical images and spectra. The algorithm iteratively evaluates possible smoothed versions of the data, the smooth models, obtaining an estimation of the underlying signal that is statistically compatible with the noisy measurements. Iterations stop based on the evidence and the $χ^2$ statistic of the last smooth model, and we compute the expected value of the signal as a weighted average of the whole set of smooth models. In this paper, we explain the mathematical formalism and numerical implementation of the algorithm, and we evaluate its performance in terms of the peak signal to noise ratio, the structural similarity index, and the time payload, using a battery of real astronomical observations. Our Fully Adaptive Bayesian Algorithm for Data Analysis (FABADA) yields results that, without any parameter tuning, are comparable to standard image processing algorithms whose parameters have been optimized based on the true signal to be recovered, something that is impossible in a real application. State-of-the-art non-parametric methods, such as BM3D, offer slightly better performance at high signal-to-noise ratio, while our algorithm is significantly more accurate for extremely noisy data (higher than $20-40\%$ relative errors, a situation of particular interest in the field of astronomy). In this range, the standard deviation of the residuals obtained by our reconstruction may become more than an order of magnitude lower than that of the original measurements. The source code needed to reproduce all the results presented in this report, including the implementation of the method, is publicly available at https://github.com/PabloMSanAla/fabada
description: 13 pages, 6 figures. Accepted for publication in RAS Techniques and Instruments
Photometric Measurements of H2O Ice Crystallinity on Trans-Neptunian Objects
Creators: name: Terai, Tsuyoshi
name: Itoh, Yoichi
name: Oasa, Yumiko
name: Furusho, Reiko
name: Watanabe, Junichi
Publisher: name: arXiv
Year: 2016
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: We present a measurement of H2O ice crystallinity on the surface of trans-neptunian objects (TNOs) with near-infrared narrow-band imaging. The newly developed photometric technique allows us to efficiently determine the strength of an 1.65-um absorption feature in crystalline H2O ice. Our data for three large objects, Haumea, Quaoar, and Orcus, which are known to contain crystalline H2O ice on the surfaces, show a reasonable result with high fractions of the crystalline phase. It can also be pointed out that if the H2O-ice grain size is larger than ~20 um, the crystallinities of these objects are obviously below 1.0, which suggest the presence of the amorphous phase. Especially, Orcus exhibits a high abundance of amorphous H2O ice compared to Haumea and Quaoar, possibly indicating a correlation between bulk density of the bodies and surface crystallization degree. We also found the presence of crystalline H2O ice on Typhon and 2008 AP129, both of which are smaller than the minimum size limit for inducing cryovolcanism as well as a transition from amorphous to crystalline through the thermal evolution due to the decay of long-lived isotopes.
description: 31 pages, 7 figures, 6 tables, accepted for publication in ApJ
Not quite in, but via Europe.
Creators: name: Gasimov, Zaur
name: Aksakal, Hasan
Publisher: name: Leipziger Universitätsverlag
Year: 2015

description: Die Schrift Lenins Detskaja bolezn‘ levizny v kommunizme wurde 1920 auf Russisch veröffentlicht und liegt seit der Istanbuler Erstveröffentlichung in den 1960er Jahren bis heute in vier Übersetzungen auf Türkisch vor. Keine einzige Übersetzung allerdings erfolgte unmittelbar aus dem russischen Original. Die französischen und englischen Versionen wurden von den türkischen Linksintellektuellen herangezogen, die sich der Popularisierung der Schrift widmeten. Neben der Verzerrung aufgrund der Übersetzung aus einer ‚dritten‘ Sprache wurde die Rezeption des Leninschen Werkes stark durch eine seit den 1920er Jahren bis in die Gegenwart andauernde linguistische Purifizierung des Türkischen geprägt. Die Rezeption Lenins in der Türkei erfolgte mittels der Übertragung der französischen und englischen Übersetzungen aus der russischen Sprache. Somit war nicht zuletzt die (sprachliche) Europäizität der Texte und Diskurse ein wichtiges Merkmal der türkisch-russischen Verflechtung.
description: Comparativ, Vol 25 No 2 (2015): Transfer and Translation
A Statistical Mechanical Model for Mass Stability in the SHP Theory
Creators: name: Horwitz, Lawrence
Publisher: name: arXiv
Year: 2016
Subjects: subject: Classical Physics (physics.class-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We construct a model for a particle in the framework of the theory of Stueckelberg, Horwitz and Piron (SHP) as an ensemble of events subject to the laws of covariant classical equilibrium statistical mechanics. The canonical and grand canonical emsembles are constructed without an a priori constraint on the total mass of the system. We show that the total mass of the system, corresponding to the mass of this particle, is determined by a chemical potential. This model has the property that under perturbation, such as collisions in the SHP theory for which the final asymptotic mass of an elementary event is not constrained by the basic theory, the particle returns to its equilibrium mass value. A mechanism similar to the Maxwell construction for more than one equlibrium mass state may result in several possible masses in the final state.
description: 12 pages,no figures. Typographical errors corrected
Greek documents from Ptolemaic Egypt : structure and influences
Creators: name: Fittall, Pamela Susan.
Publisher: name: Monash University
Year: 2022

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Topology optimization method with nonlinear diffusion
Creators: name: Oka, Tomoyuki
name: Yamada, Takayuki
Publisher: name: arXiv
Year: 2023
Subjects: subject: Optimization and Control (math.OC)
subject: FOS: Mathematics
subject: Primary: 46N10, Secondary: 35Q93, 47J35

description: This paper is concerned with topology optimization based on a level set method using (doubly) nonlinear diffusion equations. Topology optimization using the level set method is called level set-based topology optimization, which is possible to determine optimal configurations that minimize objective functionals by updating level set functions. In this paper, as an update equation for level set functions, (doubly) nonlinear diffusion equations with reaction terms are derived, and then the singularity and degeneracy of the diffusion coefficient are applied to obtain fast convergence of configurations and damping oscillation on boundary structures. In particular, the reaction terms in the proposed method do not depend on the topological derivatives, and therefore, sensitivity analysis to determine a descent direction for objective functionals is relaxed. Furthermore, a numerical algorithm for the proposed method is constructed and applied to typical minimization problems to show numerical validity. This paper is a justification and generalization of the method using reaction-diffusion equations developed by one of the authors in Yamada et al. (2010).
Potential sources of dataset bias complicate investigation of underdiagnosis by machine learning algorithms
Creators: name: Bernhardt, Mélanie
name: Jones, Charles
name: Glocker, Ben
Publisher: name: arXiv
Year: 2022
Subjects: subject: Artificial Intelligence (cs.AI)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: An increasing number of reports raise concerns about the risk that machine learning algorithms could amplify health disparities due to biases embedded in the training data. Seyyed-Kalantari et al. find that models trained on three chest X-ray datasets yield disparities in false-positive rates (FPR) across subgroups on the 'no-finding' label (indicating the absence of disease). The models consistently yield higher FPR on subgroups known to be historically underserved, and the study concludes that the models exhibit and potentially even amplify systematic underdiagnosis. We argue that the experimental setup in the study is insufficient to study algorithmic underdiagnosis. In the absence of specific knowledge (or assumptions) about the extent and nature of the dataset bias, it is difficult to investigate model bias. Importantly, their use of test data exhibiting the same bias as the training data (due to random splitting) severely complicates the interpretation of the reported disparities.
description: Published as Matters Arising in Nature Medicine
Keyserling’s Keywords:
Creators: name: Gusejnova, Dina
Publisher: name: Leipziger Universitätsverlag
Year: 2015

description: Der Beitrag betrachtet die Arbeit mit der Sprache in Hermann Keyserlings psychogeographischer Studie Das Spektrum Europas und ihren Übersetzungen ins Französische, Spanische und Englische. Theoretisch als ein Werk des postimperialen Zeitalters gewertet, lässt sich anhand einiger Beispiele nachvollziehen, wie hierarchisch die in diesem Werk zur Schau gestellte Mehrsprachigkeit ist. Daraus ergibt sich eine intellektuelle Einstellung, die man komplementär zur postkolonialen Theorie als eine Art elitärer Subalternität bezeichnen könnte. Keyserling stilisiert sich zu einem deutschsprachigen, über den Nationen stehenden Aristokraten, der den anderen europäischen Stimmen zum Klang verhilft und diese gleichzeitig abwertet. Dank seinen Übersetzern erreichte Keyserlings Werk ein weltweites Publikum. Im zweiten Teil wendet sich der Aufsatz einer biographischen Untersuchung seiner Übersetzer zu, in deren Werk nicht nur die deutsche Kultur, sondern auch die jüdische Identität von Bedeutung ist. Als mögliches Motiv für ihr Interesse an dem Text lassen sich Keyserlings ambivalente Aussagen zum Judentum anführen. In der Übersetzung zeigt sich Keyserlings Umgang mit der deutschen Sprache anders, weil das Deutsche damit von der Meistersprache des Textes zu einer unter vielen ethnographisch zu untersuchenden vernakulären Sprache herabgestuft wird. Die Übersetzer werden damit noch mehr als gewöhnlich zu Mitautoren von Keyserlings Psychogeographie und unterminieren gleichzeitig die oben als elitäre Subalternität bezeichnete Pose des Autors.
description: Comparativ, Vol 25 No 2 (2015): Transfer and Translation
Blockchain Framework for Artificial Intelligence Computation
Creators: name: You, Jie
Publisher: name: arXiv
Year: 2022
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: Artificial Intelligence (cs.AI)
subject: Machine Learning (cs.LG)
subject: Multiagent Systems (cs.MA)
subject: FOS: Computer and information sciences

description: Blockchain is an essentially distributed database recording all transactions or digital events among participating parties. Each transaction in the records is approved and verified by consensus of the participants in the system that requires solving a hard mathematical puzzle, which is known as proof-of-work. To make the approved records immutable, the mathematical puzzle is not trivial to solve and therefore consumes substantial computing resources. However, it is energy-wasteful to have many computational nodes installed in the blockchain competing to approve the records by just solving a meaningless puzzle. Here, we pose proof-of-work as a reinforcement-learning problem by modeling the blockchain growing as a Markov decision process, in which a learning agent makes an optimal decision over the environment's state, whereas a new block is added and verified. Specifically, we design the block verification and consensus mechanism as a deep reinforcement-learning iteration process. As a result, our method utilizes the determination of state transition and the randomness of action selection of a Markov decision process, as well as the computational complexity of a deep neural network, collectively to make the blocks not easy to recompute and to preserve the order of transactions, while the blockchain nodes are exploited to train the same deep neural network with different data samples (state-action pairs) in parallel, allowing the model to experience multiple episodes across computing nodes but at one time. Our method is used to design the next generation of public blockchain networks, which has the potential not only to spare computational resources for industrial applications but also to encourage data sharing and AI model design for common problems.
description: 10 pages, 4 figures
Static-Fluid Black Holes
Creators: name: Cho, Inyong
name: Kim, Hyeong-Chan
Publisher: name: arXiv
Year: 2016
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We investigate black holes formed by static perfect fluid with $p=-ρ/3$. These represent the black holes in $S_3$ and $H_3$ spatial geometries. There are three classes of black-hole solutions, two $S_3$ types and one $H_3$ type. The interesting solution is the one of $S_3$ type which possesses two singularities. The one is at the north pole behind the horizon, and the other is naked at the south pole. The observers, however, are free from falling to the naked singularity. There are also nonstatic cosmological solutions in $S_3$ and $H_3$, and a singular static solution in $H_3$.
description: 7 pages, 2 figures
Electromagnetic response of cuprate superconductors with coexisting electronic nematicity
Creators: name: Cao, Zhangkai
name: Ma, Xingyu
name: Guo, Huaiming
name: Feng, Shiping
Publisher: name: arXiv
Year: 2022
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: The electronically nematic order has emerged as a key feature of cuprate superconductors,however, its correlation with the fundamental properties such as the electromagnetic response remains unclear. Here the nematic-order state strength dependence of the electromagnetic response in cuprate superconductors is investigated within the framework of the kinetic-energy-driven superconductivity. It is shown that a significant anisotropy of the electromagnetic response is caused by the electronic nematicity. In particular, in addition to the pure d-wave component of the superconducting gap, the pure s-wave component of the superconducting gap is generated by the electronic nematicity, therefore there is a coexistence and competition of the d-wave component and the s-wave component. This coexistence and competition leads to that the maximal condensation energy appears at around the optimal strength of the electronic nematicity, and then decreases in both the weak and strong strength regions, which in turn induces the enhancement of superconductivity, and gives rise to the dome-like shape of the nematic-order state strength dependence of the superfluid density.
description: 19 pages, 5 figures, replaced some figures, added discussions and references, accepted for publication in Philosophical Magazine
GAN-based Algorithm for Efficient Image Inpainting
Creators: name: Han, Zhengyang
name: Jiang, Zehao
name: Ju, Yuan
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Image and Video Processing (eess.IV)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: 68U10

description: Global pandemic due to the spread of COVID-19 has post challenges in a new dimension on facial recognition, where people start to wear masks. Under such condition, the authors consider utilizing machine learning in image inpainting to tackle the problem, by complete the possible face that is originally covered in mask. In particular, autoencoder has great potential on retaining important, general features of the image as well as the generative power of the generative adversarial network (GAN). The authors implement a combination of the two models, context encoders and explain how it combines the power of the two models and train the model with 50,000 images of influencers faces and yields a solid result that still contains space for improvements. Furthermore, the authors discuss some shortcomings with the model, their possible improvements, as well as some area of study for future investigation for applicative perspective, as well as directions to further enhance and refine the model.
description: 6 pages, 3 figures
Automatic indexing of audiovisual material : its relevance to archival newsreels
Creators: name: Egan, Susan Patricia.
Publisher: name: Monash University
Year: 2022

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Droughts vs Hurricanes: Effects of climate change on urban streams in Puerto Rico
Creators: name: Meza-Salazar, Ana Maria
name: Ramírez, Alonso
Publisher: name: Zenodo
Year: 2020
Subjects: Climate change, Hurricane, Macroinvertebrates, Drought.

description: Tropical rivers are exposed to the pressures exerted by the rapid growth of urban areas, increasing the discharge of organic nutrients; added to the effects of climate change, such as extreme temperature events, rainfall or hurricanes. As a result of climate change, extreme events are projected to be more intense, potentially generating drastic changes in ecosystems. For example, in the Caribbean, one of the most prolonged droughts was recorded in 2015. Likewise, Hurricane María was the most intense hurricane in 2017, with severe effects mainly in Dominica and Puerto Rico. The objective of this work was to determine and contrast the impact of drought and hurricane on the assembly of aquatic macroinvertebrates in a tropical urban river to understand their vulnerability to climate change. We carried out the study in the Río Piedras, a basin that drains the San Juan metropolitan area, where the most extensive urbanization in Puerto Rico is concentrated. We carried out periodic samplings between 2014 and 2018, physicochemical and hydrological variables were recorded, and macroinvertebrates were sampled. The results show that drought has a more significant effect on the assembly of macroinvertebrates compared to the hurricane. After drought events, the abundance of macroinvertebrates decreased, and their composition differed significantly from previous samples. On the contrary, the abundance and composition of macroinvertebrates recorded after Hurricane Maria were similar to those reported in previous samplings. Although hurricanes cause flooding, macroinvertebrates appear to be adapted to these disturbances; while drought causes unusual conditions, causing changes in the macroinvertebrate assembly. Given the predictions of climate change for the Caribbean, the increase in drought events is expected to have more drastic impacts on urban river ecosystems.
No Contact Terms for the Magnetic Field in Lorentz- and CPT-Violating Electrodynamics
Creators: name: Schober, Karl
name: Altschul, Brett
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In a Lorentz- and CPT-violating modification of electrodynamics, the fields of a moving charge are known to have unusual singularities. This raises the question of whether the singular behavior may include $δ$-function contact terms, similar to those that appear in the fields of idealized dipoles. However, by calculating the magnetic field of an infinite straight wire in this theory, we demonstrate that there are no such contact terms in the magnetic field of a moving point charge
description: 13 pages
Lasting effects of static magnetic field on classical Brownian motion
Creators: name: Matevosyan, Ashot
name: Allahverdyan, Armen E.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Biological Physics (physics.bio-ph)
subject: FOS: Physical sciences

description: The Bohr-Van Leeuwen theorem states that an external static magnetic field does not influence the state of a classical equilibrium system: there is no equilibrium classical magnetism, since the magnetic field does not do work. We revisit this famous no-go result and consider a classical charged Brownian particle interacting with an equilibrium bath. We confirm that the Bohr-Van Leeuwen theorem holds for the long-time (equilibrium) state of the particle. But the external static, homogeneous magnetic field does influence the long-time state of the thermal bath, which is described via the Caldeira-Leggett model. In particular, the magnetic field induces an average angular momentum for the (uncharged!) bath, which separates into two sets rotating in opposite directions. The effect relates to the bath going slightly out of equilibrium under the influence of the Brownian particle and persists for arbitrarily long times. In this context we studied the behavior of the two other additive integrals of motion, energy and linear momentum. The situation with linear momentum is different, because it is dissipated away by (and from) the bath modes. The average energy of the bath mode retains the magnetic field as a small correction. Thus, only the bath angular momentum really feels the magnetic field for long times.
description: 6+9 pages, one figure; revised and extended version; we added new results on linear momentum transfer
The blame game: Understanding blame assignment in social media
Creators: name: Xi, Ruijie
name: Singh, Munindar P.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Social and Information Networks (cs.SI)
subject: FOS: Computer and information sciences

description: Cognitive and psychological studies on morality have proposed underlying linguistic and semantic factors. However, laboratory experiments in the philosophical literature often lack the nuances and complexity of real life. This paper examines how well the findings of these cognitive studies generalize to a corpus of over 30,000 narratives of tense social situations submitted to a popular social media forum. These narratives describe interpersonal moral situations or misgivings; other users judge from the post whether the author (protagonist) or the opposing side (antagonist) is morally culpable. Whereas previous work focuses on predicting the polarity of normative behaviors, we extend and apply natural language processing (NLP) techniques to understand the effects of descriptions of the people involved in these posts. We conduct extensive experiments to investigate the effect sizes of features to understand how they affect the assignment of blame on social media. Our findings show that aggregating psychology theories enables understanding real-life moral situations. Moreover, our results suggest that there exist biases in blame assignment on social media, such as males are more likely to receive blame no matter whether they are protagonists or antagonists.
description: Submitted to ICWSM 2022
Glassy Dynamics of Brownian Particles with Velocity-Dependent Friction
Creators: name: Yazdi, Anoosheh
name: Sperl, Matthias
Publisher: name: arXiv
Year: 2016
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We consider a two-dimensional model system of Brownian particles in which slow particles are accelerated while fast particles are damped. The motion of the individual particles are described by a Langevin equation with Rayleigh-Helmholtz velocity dependent friction. In case of noninteracting particles, the time evolution equations lead to a non-Gaussian velocity distribution. The velocity dependent friction allows negative values of the friction or energy intakes by slow particles which we consider as active motion, and also causes breaking of the fluctuation dissipation relation. Defining the effective temperature proportional to the second moment of velocity, it is shown that for a constant effective temperature the higher the noise strength, the lower are the number of active particles in the system. Using the Mori-Zwanzig formalism and the mode-coupling approximation, the equation of motion for the density auto-correlation function are derived. The equations are solved using the equilibrium structure factors. The integration-through-transients approach is used to derive a relation between the structure factor in the stationary state considering the interacting forces, and the conventional equilibrium static structure factor.
description: 13 pages, 8 figures, accepted for publication in Physical Review E
Droughts vs Hurricanes: Effects of climate change on urban streams in Puerto Rico
Creators: name: Meza-Salazar, Ana Maria
name: Ramírez, Alonso
Publisher: name: Zenodo
Year: 2020
Subjects: Climate change, Hurricane, Macroinvertebrates, Drought.

description: Tropical rivers are exposed to the pressures exerted by the rapid growth of urban areas, increasing the discharge of organic nutrients; added to the effects of climate change, such as extreme temperature events, rainfall or hurricanes. As a result of climate change, extreme events are projected to be more intense, potentially generating drastic changes in ecosystems. For example, in the Caribbean, one of the most prolonged droughts was recorded in 2015. Likewise, Hurricane María was the most intense hurricane in 2017, with severe effects mainly in Dominica and Puerto Rico. The objective of this work was to determine and contrast the impact of drought and hurricane on the assembly of aquatic macroinvertebrates in a tropical urban river to understand their vulnerability to climate change. We carried out the study in the Río Piedras, a basin that drains the San Juan metropolitan area, where the most extensive urbanization in Puerto Rico is concentrated. We carried out periodic samplings between 2014 and 2018, physicochemical and hydrological variables were recorded, and macroinvertebrates were sampled. The results show that drought has a more significant effect on the assembly of macroinvertebrates compared to the hurricane. After drought events, the abundance of macroinvertebrates decreased, and their composition differed significantly from previous samples. On the contrary, the abundance and composition of macroinvertebrates recorded after Hurricane Maria were similar to that reported in previous samplings. Although hurricanes cause flooding, macroinvertebrates appear to be adapted to these disturbances; while drought causes unusual conditions, causing changes in the macroinvertebrate assembly. Given the predictions of climate change for the Caribbean, the increase in drought events is expected to have more drastic impacts on urban river ecosystems.
Fast Object Inertial Parameter Identification for Collaborative Robots
Creators: name: Nadeau, Philippe
name: Giamou, Matthew
name: Kelly, Jonathan
Publisher: name: arXiv
Year: 2022
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: Collaborative robots (cobots) are machines designed to work safely alongside people in human-centric environments. Providing cobots with the ability to quickly infer the inertial parameters of manipulated objects will improve their flexibility and enable greater usage in manufacturing and other areas. To ensure safety, cobots are subject to kinematic limits that result in low signal-to-noise ratios (SNR) for velocity, acceleration, and force-torque data. This renders existing inertial parameter identification algorithms prohibitively slow and inaccurate. Motivated by the desire for faster model acquisition, we investigate the use of an approximation of rigid body dynamics to improve the SNR. Additionally, we introduce a mass discretization method that can make use of shape information to quickly identify plausible inertial parameters for a manipulated object. We present extensive simulation studies and real-world experiments demonstrating that our approach complements existing inertial parameter identification methods by specifically targeting the typical cobot operating regime.
description: In Proceedings of the IEEE International Conference on Robotics and Automation (ICRA'22), Philadelphia, USA, May 23-27, 2022
Universal temporal features of rankings in competitive sports and games
Creators: name: Morales, José A.
name: Sánchez, Sergio
name: Flores, Jorge
name: Pineda, Carlos
name: Gershenson, Carlos
name: Cocho, Germinal
name: Zizumbo, Jerónimo
name: Iñiguez, Gerardo
Publisher: name: arXiv
Year: 2016
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: Applications (stat.AP)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: Many complex phenomena, from the selection of traits in biological systems to hierarchy formation in social and economic entities, show signs of competition and heterogeneous performance in the temporal evolution of their components, which may eventually lead to stratified structures such as the wealth distribution worldwide. However, it is still unclear whether the road to hierarchical complexity is determined by the particularities of each phenomena, or if there are universal mechanisms of stratification common to many systems. Human sports and games, with their (varied but simplified) rules of competition and measures of performance, serve as an ideal test bed to look for universal features of hierarchy formation. With this goal in mind, we analyse here the behaviour of players and team rankings over time for several sports and games. Even though, for a given time, the distribution of performance ranks varies across activities, we find statistical regularities in the dynamics of ranks. Specifically the rank diversity, a measure of the number of elements occupying a given rank over a length of time, has the same functional form in sports and games as in languages, another system where competition is determined by the use or disuse of grammatical structures. Our results support the notion that hierarchical phenomena may be driven by the same underlying mechanisms of rank formation, regardless of the nature of their components. Moreover, such regularities can in principle be used to predict lifetimes of rank occupancy, thus increasing our ability to forecast stratification in the presence of competition.