cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Typical properties of optimal growth in the Von Neumann expanding model for large random economies
Creators: name: De Martino, Andrea
name: Marsili, Matteo
Publisher: name: arXiv
Year: 2005
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: General Finance (q-fin.GN)
subject: FOS: Physical sciences
subject: FOS: Economics and business

description: We calculate the optimal solutions of the fully heterogeneous Von Neumann expansion problem with $N$ processes and $P$ goods in the limit $N\to\infty$. This model provides an elementary description of the growth of a production economy in the long run. The system turns from a contracting to an expanding phase as $N$ increases beyond $P$. The solution is characterized by a universal behavior, independent of the parameters of the disorder statistics. Associating technological innovation to an increase of $N$, we find that while such an increase has a large positive impact on long term growth when $N\ll P$, its effect on technologically advanced economies ($N\gg P$) is very weak.
description: 8 pages, 1 figure
Garaudy, Roger / Metz, Johann Baptist / Rahner, Karl, Der Dialog oder Ändert sich das Verhältnis zwischen Katholizismus und Marxismus? ...
Creators: name: Rendtorff, Trutz
Publisher: name: Ökumenische Rundschau
Year: 2025

description: Ökumenische Rundschau, Bd. 16 Nr. 3 (1967): Ökumenische Rundschau, Band 16, Heft 3
MARKET INVERSION IN COMMODITY FUTURES PRICES
Creators: name: Yoon, Byung-Sam
name: Brorsen, B. Wade
name: Yoon, Byung-Sam
name: Brorsen, B. Wade
Publisher: name: Unknown
Year: 2001
Subjects: Demand and Price Analysis

description: As opposed to a normal market, an inverted market has a negative price of storage or spread. Market inversions in nearby spreads rarely occur during early months of the crop year since stocks are usually abundant after harvest. However, market inversions frequently occur when the spreads are observed across crop years near the end of the crop year. The regressions of spreads on the logarithm of U.S. quarterly stocks show that there exists a positive relationship between the spread and the level of stocks, and further implies that when stocks are scarce, markets will be inverted. Simulations are conducted to determine whether a market inversion is a signal to sell the stocks. The results of the paired-difference tests reveal that as the crop cycle advances towards the end of the crop year, market inversions clearly reflect the market's signal to release stocks in anticipation of new crop supplies. The regressions of actual returns to storage on predicted returns to storage clearly show that a market inversion is a signal to sell. The results support the behavioral finance hypothesis that producers are choosing to hold excess stocks because of some type of biased expectations.
Weak Boundary Condition Enforcement for Linear Kirchhoff-Love Shells: Formulation, Error Analysis, and Verification
Creators: name: Benzaken, Joseph
name: Evans, John A.
name: McCormick, Stephen
name: Tamstorf, Rasmus
Publisher: name: arXiv
Year: 2020
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics
subject: 35Q74, 74K25

description: Stable and accurate modeling of thin shells requires proper enforcement of all types of boundary conditions. Unfortunately, for Kirchhoff-Love shells, strong enforcement of Dirichlet boundary conditions is difficult because both functional and derivative boundary conditions must be applied. A popular alternative is to employ Nitsche's method to weakly enforce all boundary conditions. However, while many Nitsche-based formulations have been proposed in the literature, they lack comprehensive error analyses and verifications. In fact, existing formulations are variationally inconsistent and yield sub-optimal convergence rates when used with common boundary condition specifications. In this paper, we present a novel Nitsche-based formulation for the linear Kirchhoff-Love shell that is provably stable and optimally convergent for general sets of admissible boundary conditions. To arrive at our formulation, we first present a framework for constructing Nitsche's method for any abstract variational constrained minimization problem. We then apply this framework to the linear Kirchhoff-Love shell and, for the particular case of NURBS-based isogeometric analysis, we prove that the resulting formulation yields optimal convergence rates in both the shell energy norm and the standard $L^2$-norm. In the process, we derive the Euler-Lagrange equations for general sets of admissible boundary conditions and show that the Euler-Lagrange boundary conditions typically presented in the literature is incorrect. We verify our formulation by manufacturing solutions for a new shell obstacle course that encompasses flat, parabolic, hyperbolic, and elliptic geometric configurations. These manufactured solutions allow us to robustly measure the error across the entire shell in contrast with current best practices where displacement and stress errors are only measured at specific locations.
description: 51 pages, 9 figures
Income Enhancing and Risk Management Properties of Marketing Practices
Creators: name: Peterson, Hikaru Hanawa
name: Tomek, William G.
name: Peterson, Hikaru Hanawa
name: Tomek, William G.
Publisher: name: Unknown
Year: 2001
Subjects: subject: Marketing
subject: FOS: Economics and business

description: A rational expectations storage model is used to simulate monthly corn prices, which are used to evaluate marketing strategies to manage price risk. The data are generated and analyzed in two formats: for long-run outcomes over 10,000 "years" of monthly prices and for 10,000 cases of 40-year "lifetimes." Three categories of strategies are analyzed: frequency of post-harvest cash sales, unconditional hedges, and conditional hedges. The comparisons are based on the simulated probability distributions of net returns. One conclusion is that diversifying cash sales, without hedging, is not an efficient means of risk management. Unhedged storage does not reduce risk and, on average, reduces returns. The analysis of the 40-year lifetimes demonstrates, however, that rational decision-makers can face "lucky" and "unlucky" time periods. Thus, although the long-run analysis suggests that routine hedging reduces the variance (and the mean) of returns compared to the base case of selling in the spot market at harvest, the variance of returns (and their means) from both strategies will vary from lifetime to lifetime. Efficient strategies for producers with increasing utility functions vary from lifetime to lifetime, suggesting that efficient strategies likely vary from year-to-year. Nonetheless, strategies that take advantage of locking in returns to storage when relative prices are favorable are efficient in the second-degree sense and appear robust across different lifetimes. We also illustrate that conclusions are influenced by the measure of risk used. Perhaps the major conclusion is, however, that risk-management analysis is complex and potentially filled with pitfalls.
Evidence for the Alternating Next-Nearest Neighbor model in the dynamic behavior of a frustrated antiferromagnet
Creators: name: Carr, Adra
name: Bowlan, John
name: 3
name: Mazzoli, Claudio
name: Barbour, Andi
name: Hu, Wen
name: Wilkins, Stuart
name: Walker, Colby
name: Ding, Xiaxin
name: Kim, Jong Hyuk
name: Lee, Nara
name: Choi, Young Jai
name: Lin, Shi-Zeng
name: Sandberg, Richard L.
name: Zapf, Vivien S.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: X-ray photon correlation spectroscopy (XPCS) enables us to study dynamics of antiferromagnets. Using coherent soft X-ray diffraction, we resonantly probe Mn and Co Bragg peaks in the frustrated magnetic chain compound Lu2CoMnO6 significantly below the Neel temperature. Bragg peaks of incommensurate order slide towards commensurate 'up up down down' order with decreasing temperature. Antiferromagnetic inhomogeneities produce speckle within the Bragg peaks, whose dynamics are probed by XPCS and compared to the classic Axial Next-Nearest Neighbor Interaction model of frustration. The data supports a novel model prediction: with decreasing temperature the dynamics become faster.
Thirsty downstream : the provision of clean water in Jakarta, Indonesia
Creators: name: Argo, Teti Armiati
Publisher: name: University of British Columbia
Year: 2009

description: The challenge of water provision in third world cities is to maintain the supply in the context of inadequate and inefficient piped water infrastructure and diminishing raw resources. In order to examine the role of governance in this, I utilize a range of theoretical positions: the welfare orientation, rational choice paradigm, common goods theory and regime theory, and present them as ways to explore the subjective dimension of water provision. Using the city of Jakarta, Indonesia as a case study, this dissertation explores the issues using different perspectives on a single principal focus, the roles of the government and its relations to non-governmental actors. This research used data from secondary materials such as management reports, policy and academic reports, and scientific studies. The major source of primary data were interviews conducted with about 40 key actors. Qualitative analysis used a system of information coding and triangulation. The conclusion reached is that the approach to managing clean water provision needs to be redefined in relation to the water management regimes found in situated research. In Jakarta, one may define three regimes: piped water, surface and shallow groundwater, and deep groundwater. Accessing water from greater urban watershed, treatment plants and a "manufacturing process" results in the delivery of a product. Such a system reduces the possibility of the tragedy of the commons, that is, the over-extraction of groundwater by individuals. But a more inclusive and enforced regulatory system must be established for groundwater, as it remains a needed source of supply. Local and low-technology solutions, international agency assistance, the policies of privatization and decentralization, and better land use planning, all hold out the promise of movement towards a solution. But, as the case study demonstrates, success has so far been mixed. Many options do not address water scarcity at the city level and problems of inequitable service. It is only the prospect government reform towards a better allocation of roles, new management ideas and greater co-operation within and among the water regimes that will lead to better provision of clean water.
Magnetic Braking of Ap/Bp Stars: Application to Compact Black-Hole X-Ray Binaries
Creators: name: Justham, S.
name: Rappaport, S.
name: Podsiadlowski, Ph.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We examine the proposal that the subset of neutron-star and black-hole X-ray binaries that form with Ap or Bp star companions will experience systemic angular-momentum losses due to magnetic braking, not otherwise operative with intermediate-mass companion stars. We suggest that for donor stars possessing the anomalously high magnetic fields associated with Ap and Bp stars, a magnetically coupled, irradiation-driven stellar wind can lead to substantial systemic loss of angular-momentum. In this paper we apply this mechanism to a specific astrophysics problem involving the formation of compact black-hole binaries with low-mass donor stars. At present, it is not understood how these systems form, given that low-mass companion stars are not likely to provide sufficient gravitational potential to unbind the envelope of the massive progenitor of the black hole during a prior `common-envelope' phase. However, in the absence of magnetic braking, such systems tend to evolve to long orbital periods. We show that, with the proposed magnetic braking properties afforded by Ap and Bp companions, such a scenario can lead to the formation of compact black-hole binaries with orbital periods, donor masses, lifetimes, and production rates that are in accord with the observations. In spite of these successes, our models reveal a significant discrepancy between the calculated effective temperatures and the observed spectral types of the donor stars. Finally, we show that this temperature discrepancy would still exist for other scenarios invoking initially intermediate-mass donor stars, and this presents a substantial unresolved mystery.
description: Accepted by MNRAS. 10 pages with 5 figures (one reduced-quality to minimise file size)
[Fragment of unfinished autobiography - Fort William and Teachers College Units]
Creators: name: Johns, Ethel
Publisher: name: The University of British Columbia
Year: 2015

description: Fragment of Ethel Johns' unfinished autobiography, describing her experiences as superintendent of McKellar General Hospital in Fort William (1911-13), and attending Teachers College, Columbia University, studying basic sciences, principles of public health, teaching methods, and nursing school administration (1914-15). The latter section includes detailed observations of well-known nursing educators from that period.
Pages are heavily annotated.
Outburst and Splitting of Interstellar Comet 2I/Borisov
Creators: name: Jewitt, David
name: Kim, Yoonyoung
name: Mutchler, Max
name: Weaver, Harold
name: Agarwal, Jessica
name: Hui, Man-To
Publisher: name: arXiv
Year: 2020
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: We present Hubble Space Telescope observations of a photometric outburst and splitting event in interstellar comet 2I/Borisov. The outburst, first reported with the comet outbound at 2.8 AU (Drahus et al.~2020), was caused by the expulsion of solid particles having a combined cross-section about 100 sq. km and a mass in 0.1 mm sized particles about 2e7 kg. The latter corresponds to 1e-4 of the mass of the nucleus, taken as a sphere of radius 500 m. A transient ``double nucleus'' was observed on UT 2020 March 30 (about three weeks after the outburst), having a cross-section about 0.6 sq. km and corresponding dust mass 1e5 kg. The secondary was absent in images taken on and before March 28, and in images taken on and after April 03. The unexpectedly delayed appearance and rapid disappearance of the secondary are consistent with an origin through rotational bursting of one or more large (meter-sized) boulders under the action of outgassing torques, following their ejection from the main nucleus. Overall, our observations reveal that the outburst and splitting of the nucleus are minor events involving a negligible fraction of the total mass: 2I/Borisov will survive its passage through the planetary region largely unscathed.
description: 21 pages, 5 figures, 1 appendix
Free-standing 2D metals from binary metal alloys
Creators: name: Nevalaita, Janne
name: Koskinen, Pekka
Publisher: name: arXiv
Year: 2020
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Recent experiment demonstrated the formation of free-standing Au monolayers by exposing Au-Ag alloy to electron beam irradiation. Inspired by this discovery, we used semi-empirical effective medium theory simulations to investigate monolayer formation in 30 different binary metal alloys composed of late d-series metals Ni, Cu, Pd, Ag, Pt, and Au. In qualitative agreement with the experiment, we find that the beam energy required to dealloy Ag atoms from Au-Ag alloy is smaller than the energy required to break the dealloyed Au monolayer. Our simulations suggest that similar method could also be used to form Au monolayers from Au-Cu alloy and Pt monolayers from Pt-Cu, Pt-Ni, and Pt-Pd alloys.
description: 4 pages, 4 figures
Stöhr, Martin (Hrsg.), Disputation zwischen Christen und Marxisten
Creators: name: Rendtorff, Trutz
Publisher: name: Ökumenische Rundschau
Year: 2025

description: Ökumenische Rundschau, Bd. 16 Nr. 3 (1967): Ökumenische Rundschau, Band 16, Heft 3
HYPOTHESIS TESTING USING NUMEROUS APPROXIMATING FUNCTIONAL FORMS
Creators: name: Norwood, F. Bailey
name: Lusk, Jayson L.
name: Ferrier, Peyton Michael
name: Norwood, F. Bailey
name: Lusk, Jayson L.
name: Ferrier, Peyton Michael
Publisher: name: Unknown
Year: 2001
Subjects: Research Methods/ Statistical Methods

description: While the combination of several or more models is often found to improve forecasts (Brandt and Bessler, Min and Zellner, Norwood and Schroeder), hypothesis tests are typically conducted using a single model approach 1 . Hypothesis tests and forecasts have similar goals; they seek to define a range over which a parameter should lie within a degree of confidence. If it is true that, on average, composite forecasts are more accurate than a single model's forecast, it might also be true that hypothesis tests using information from numerous models are, on average, more accurate in the sense of lower Type I and Type II errors than hypothesis tests using a single model.
EVALUATION OF HEDGING IN THE PRESENCE OF CROP INSURANCE AND GOVERNMENT LOAN PROGRAMS
Creators: name: Zuniga, Manuel
name: Coble, Keith H.
name: Heifner, Richard G.
name: Zuniga, Manuel
name: Coble, Keith H.
name: Heifner, Richard G.
Publisher: name: Unknown
Year: 2001
Subjects: subject: Agricultural Finance
subject: Marketing
subject: FOS: Economics and business

description: This research evaluates the interaction of new alternative insurance designs, forward pricing tools and the government revenue protection program while assuming a government loan program is in place. A numerical analysis is conducted using a revenue simulation model that incorporates futures prices, basis, and yield variability. Three crop insurance designs at 75 percent of yield guarantee are evaluated. Optimal futures and at-the-money put option hedge ratios are derived for expected utility maximizing of soybean producers. Sensitivity to loan rate levels are examined. Our results suggest that loan programs profoundly alter the optimal producer strategy.
The principle of least action and the geometric basis of D-branes
Creators: name: Yin, Zheng
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We analyze thoroughly the boundary conditions allowed in classical non-linear sigma models and derive from first principle the corresponding geometric objects, i.e. D-branes. In addition to giving classical D-branes an intrinsic and geometric foundation, D-branes in nontrivial H flux and D-branes embedded within D-branes are precisely defined. A well known topological condition on D-branes is replaced.
Quantum Monte Carlo study of topological phases on a spin analogue of Benalcazar-Bernevig-Hughes model
Creators: name: Guo, Jiaojiao
name: Sun, Junsong
name: Zhu, Xingchuan
name: Li, Chang-An
name: Guo, Huaiming
name: Feng, Shiping
Publisher: name: arXiv
Year: 2020
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We study the higher-order topological spin phases based on a spin analogue of Benalcazar-Bernevig-Hughes model in two dimensions using large-scale quantum Monte Carlo simulations. A continuous Néel-valence bond solid quantum phase transition is revealed by tuning the ratio between dimerized spin couplings, namely, the weak and strong exchange couplings. Through the finite-size scaling analysis, we identify the phase critical points, and consequently, map out the full phase diagrams in related parameter spaces. Particularly, we find that the valence bond solid phase can be a higher-order topological spin phase, which has a gap for spin excitations in the bulk while demonstrates characteristic gapless spin modes at corners of open lattices. We further discuss the connection between the higher-order topological spin phases and the electronic correlated higher-order phases, and find both of them possess gapless spin corner modes that are protected by higher-order topology. Our result exemplifies higher-order physics in the correlated spin systems and will contribute to further understandings of the many-body higher-order topological phenomena.
description: 13 pages, 13 figures
title: Η εξέλιξη των γαλακτοκομικών προϊόντων από την φάρμα στην βιομηχανία του 21ου αιώνα
title: The evolusion of dairy products from the farm to the industry of the 21st century
titleType: AlternativeTitle
Creators: name: Τούση, Μαρία Ελένη
Publisher: name: Πανεπιστήμιο Δυτικής Αττικής
Year: 2021
Subjects: Γάλα
Γαλακτοκομικά προϊόντα
Εναλλακτικά προϊόντα
Φυτικά ροφήματα

description: Η εξέλιξη των τροφίμων στις μέρες μας αποτελεί ένα μείζον θέμα για την επιστημονική και την κοινωνία. Ένας βασικός κλάδος των τροφίμων είναι εκείνος των γαλακτοκομικών προϊόντων πάνω στον οποίο βασίζεται και η παρούσα πτυχιακή. Η διατροφή του ανθρώπου εμπεριέχει σε μεγάλο ποσοστό την κατανάλωση γαλακτοκομικών προϊόντων, ανάγκη που οδήγησε τις βιομηχανίες στη δημιουργία νέων προϊόντων. Με βάση το ιστορικό υπόβαθρο, η εκμετάλλευση των ζώων για το γάλα τους ξεκίνησε από τον άνθρωπο και αργότερα από τις βιομηχανίες για τη κάλυψη αναγκών σε γαλακτοκομικά προϊόντα. Η σπουδαιότητά τους οφείλεται στα ευεργετικά χαρακτηριστικά του γάλακτος. Κάποια από τα προϊόντα που υπάρχουν στην αγορά είναι το UHT γάλα, το συμπυκνωμένο γάλα, το σακχαρούχο, η γιαούρτη με προβιοτικά, το κεφίρ κ.α. Εμφανή είναι βελτίωση των βιομηχανιών πάνω σε αυτόν τον τομέα από την δημιουργία φυτικών ως εναλλακτική λύση των ζωικής προέλευσης αγαθών. Με αφορμή κάποια προβλήματα υγείας, τα φυτικά ροφήματα όχι απλά αποτελούν εναλλακτική λύση, άλλα αντικατάσταση των γαλακτοκομικών. Αναλύονται ορισμένα από τα φυτικά ροφήματα, όπως το ρόφημα “γάλα” σόγιας, αμυγδάλου, ρυζιού, καρύδας, βρώμης, φυστικού. Για να γίνει αυτό, δημιουργήθηκε ένα ερωτηματολόγιο με σκοπό να παρατηρηθεί σε ποιο βαθμό οι άνθρωποι καταναλώνουν γαλακτοκομικά ή μη προϊόντα, καθώς και ποια οφέλη στην υγεία έχει η συχνή ή μη κατανάλωση των προαναφερθέντων αγαθών. Τέλος, συμπεραίνεται αν η εξέλιξη αυτή είναι ευεργετική για τον άνθρωπο.
Local Polynomial Kernel Forecasts and Management of Price Risks using Futures Markets
Creators: name: Kim, MinKyoung
name: Leuthold, Raymond M.
name: Garcia, Philip
name: Kim, MinKyoung
name: Leuthold, Raymond M.
name: Garcia, Philip
Publisher: name: Unknown
Year: 2001
Subjects: subject: Marketing
subject: FOS: Economics and business

description: This study contributes to understanding price risk management through hedging strategies in a forecasting context. A relatively new forecasting method, nonparametric local polynomial kernel (LPK), is used and applied to the hog sector. The selective multiproduct hedge based on the LPK price and hedge ratio forecasts is, in general, found to be better than continuous hedge and alternative forecasting procedures in terms of reduction of variance of unhedged return. The findings indicate that combining hedging with forecasts, especially when using the LPK technique, can potentially improve price risk management.
MeerKAT-16 HI observation of the dIrr galaxy WLM
Creators: name: Ianjamasimanana, Roger
name: Namumba, Brenda
name: Ramaila, Athanaseus J. T.
name: Saburova, Anna S.
name: Jozsa, Gyula I. G.
name: Myburgh, Talon
name: Thorat, Kshitij
name: Carignan, Claude
name: Maina, Eric
name: de Blok, W. J. G.
name: Andati, Lexy A. L.
name: Hugo, Benjamin V.
name: Kleiner, Dane
name: Kamphuis, Peter
name: Serra, Paolo
name: Smirnov, Oleg M.
name: Maccagni, Filippo M.
name: Makhathini, Sphesihle
name: Molnar, Daniel Cs.
name: Perkins, Simon
name: Ramatsoku, Mpati
name: White, Sarah V.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present observations and models of the kinematics and the distribution of the neutral hydrogen (HI) in the isolated dwarf irregular galaxy, Wolf-Lundmark-Melotte (WLM). We observed WLM with the Green Bank Telescope (GBT) and as part of the MeerKAT Early Science Programme, where 16 dishes were available. The HI disc of WLM extends out to a major axis diameter of 30 arcmin (8.5 kpc), and a minor axis diameter of 20 arcmin (5.6 kpc) as measured by the GBT. We use the MeerKAT data to model WLM using the TiRiFiC software suite, allowing us to fit different tilted-ring models and select the one that best matches the observation. Our final best-fitting model is a flat disc with a vertical thickness, a constant inclination and dispersion, and a radially-varying surface brightness with harmonic distortions. To simulate bar-like motions, we include second-order harmonic distortions in velocity in the tangential and the vertical directions. We present a model with only circular motions included and a model with non-circular motions. The latter describes the data better. Overall, the models reproduce the global distribution and the kinematics of the gas, except for some faint emission at the 2-sigma level. We model the mass distribution of WLM with a pseudo-isothermal (ISO) and a Navarro-Frenk-White (NFW) dark matter halo models. The NFW and the ISO models fit the derived rotation curves within the formal errors, but with the ISO model giving better reduced chi-square values. The mass distribution in WLM is dominated by dark matter at all radii.
description: Accepted for publication in MNRAS, 25 pages, 21 figures, 5 tables
Conic sheaves on subanalytic sites and Laplace transform
Creators: name: Prelli, Luca
Publisher: name: arXiv
Year: 2005
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 18F10, 32B20, 44A10

description: In this paper we give a construction of conic sheaves on a subanalytic site and we extend the Fourier-Sato transform to this framework. Let E be a n dimensional complex vector space and let E^* be its dual. As an application we construct the conic sheaves $\OO^t_{E_{\RP}}$ and $\OO^w_{E_{\RP}}$ of tempered and Whitney holomorphic functions respectively and we give a sheaf theoretical interpretation of the Laplace isomorphisms of Kashiwara and Schapira which give the isomorphisms in the derived category $\OO^{t\land}_{E_{\RP}}[n] \simeq \OO^t_{E^*_{\RP}}$ and $\OO^{w\land}_{E_{\RP}}[n] \simeq \OO^w_{E^*_{\RP}}$.
description: 36 pages, uses xy-pic
Universal Rényi Entropy of Quasiparticle Excitations
Creators: name: Zhang, Jiaju
name: Rajabpour, M. A.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: High Energy Physics - Theory (hep-th)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The Rényi entropies of quasiparticle excitations in the many-body gapped systems show a remarkable universal picture which can be understood partially by combination of a semiclassical argument with the quantum effect of (in)distinguishability. The universal Rényi entropies are independent of the model, the quasiparticle momenta, and the connectedness of the subsystem. In this letter we calculate exactly the single-interval and double-interval Rényi entropies of quasiparticle excitations in the many-body gapped fermions, bosons, and XY chains. We find additional contributions to the universal Rényi entropy in the excited states with quasiparticles of different momenta. The additional terms are different in the fermionic and bosonic chains, depend on the momentum differences of the quasiparticles, and are different for the single interval and the double interval. We derive the analytical Rényi entropy in the extremely gapped limit, matching perfectly the numerical results as long as either the intrinsic correlation length of the model or all the de Broglie wavelengths of the quasiparticles are small. When the momentum difference of any pair of distinct quasiparticles is small, the additional terms are non-negligible. On the contrary, when the difference of the momenta of each pair of distinct quasiparticles is large, the additional terms could be neglected. The universal single-interval Rényi entropy and its additional terms in the XY chain are the same as those in the fermionic chain, while the universal Rényi entropy of the double intervals and its additional terms are different, due to the fact that the local degrees of freedom of the XY chain are the Pauli matrices not the spinless fermions. We argue that the derived formulas have universal properties and can be applied for a wider range of models than those discussed here.
description: published version: 7 pages, 4 figures
The storage capacity of Potts models for semantic memory retrieval
Creators: name: Kropff, Emilio
name: Treves, Alessandro
Publisher: name: arXiv
Year: 2005
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: We introduce and analyze a minimal network model of semantic memory in the human brain. The model is a global associative memory structured as a collection of N local modules, each coding a feature, which can take S possible values, with a global sparseness a (the average fraction of features describing a concept). We show that, under optimal conditions, the number c of modules connected on average to a module can range widely between very sparse connectivity (c/N -> 0) and full connectivity (c = N), maintaining a global network storage capacity (the maximum number p of stored and retrievable concepts) that scales like c*S^2/a, with logarithmic corrections consistent with the constraint that each synapse may store up to a fraction of a bit.
description: Accepted for publication in J-STAT, July 2005
On the Maillet--Baker continued fractions
Creators: name: Adamczewski, Boris
name: Bugeaud, Yann
Publisher: name: arXiv
Year: 2005
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 11J81, 11J70, 68R15

description: We use the Schmidt Subspace Theorem to establish the transcendence of a class of quasi-periodic continued fractions. This improves earlier works of Maillet and of A. Baker. We also improve an old result of Davenport and Roth on the rate of increase of the denominators of the convergents to any real algebraic number.
An Effectiveness Metric for Ordinal Classification: Formal Properties and Experimental Results
Creators: name: Amigó, Enrique
name: Gonzalo, Julio
name: Mizzaro, Stefano
name: Carrillo-de-Albornoz, Jorge
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computation and Language (cs.CL)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences
subject: I.2.7

description: In Ordinal Classification tasks, items have to be assigned to classes that have a relative ordering, such as positive, neutral, negative in sentiment analysis. Remarkably, the most popular evaluation metrics for ordinal classification tasks either ignore relevant information (for instance, precision/recall on each of the classes ignores their relative ordering) or assume additional information (for instance, Mean Average Error assumes absolute distances between classes). In this paper we propose a new metric for Ordinal Classification, Closeness Evaluation Measure, that is rooted on Measurement Theory and Information Theory. Our theoretical analysis and experimental results over both synthetic data and data from NLP shared tasks indicate that the proposed metric captures quality aspects from different traditional tasks simultaneously. In addition, it generalizes some popular classification (nominal scale) and error minimization (interval scale) metrics, depending on the measurement scale in which it is instantiated.
description: To appear in Proceedings of ACL 2020
Conformal field theories are magical
Creators: name: White, Christopher David
name: Cao, ChunJun
name: Swingle, Brian
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: "Magic" is the degree to which a state cannot be approximated by Clifford gates. We study mana, a measure of magic, in the ground state of the $\mathbb Z_3$ Potts model, and argue that it is a broadly useful diagnostic for many-body physics. In particular we find that the $q = 3$ ground state has large mana at the model's critical point, and that this mana resides in the system's correlations. We explain the form of the mana by a simple tensor-counting calculation based on a MERA representation of the state. Because mana is present at all length scales, we conclude that the conformal field theory describing the 3-state Potts model critical point is magical. These results control the difficulty of preparing the Potts ground state on an error-corrected quantum computer, and constrain tensor network models of AdS-CFT.
The Role of the Bid-Ask Spread in a Dynamic - Time-Varying Optimal Hedging Model
Creators: name: Haigh, Michael S.
name: Haigh, Michael S.
Publisher: name: Unknown
Year: 2001
Subjects: subject: Marketing
subject: FOS: Economics and business

description: This paper presents a manageable and effective way of nesting two popular, yet distinct approaches to obtain optimal hedging ratios - time-series econometrics (GARCH) and dynamic programming (DP). The nested DP-GARCH model is then compared to a DP-GARCH model that accounts for variability in the bid-ask spread often unobserved (and hence ignored) in most studies. Results from an empirical application using data from an importantly traded commodity " sugar " suggest that a DP-GARCH model that incorporates the bid-ask spread still outperforms more traditional models. Moreover, the hedging ratios are far less volatile, and statistically different, than those recommended by the traditional GARCH methods that ignore the spread.
The Island state of the Atoll Source 4U 1820--30
Creators: name: Altamirano, Diego
name: van der Klis, M.
name: Méndez, M.
name: Migliari, S.
name: Jonker, P. G.
name: Tiengo, A.
name: Zhang, W.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We study the rapid X-ray time variability in all public data available from the \textit{Rossi X-ray Timing Explorer's} Proportional Counter Array on the atoll source 4U 1820--30 in the low-luminosity island state. A total of $\sim46$ ks of data were used. We compare the frequencies of the variability components of 4U 1820--30 with those in other atolls sources. These frequencies were previously found to follow a universal scheme of correlations. We find that 4U 1820--30 shows correlations that are shifted by factors of $1.13\pm0.01$ and $1.21\pm0.02$ with respect to those in other atoll sources. These shifts are similar to, but smaller than the shift factor $\sim1.45$ previously reported for some accreting millisecond pulsars. Therefore, 4U 1820--30 is the first atoll source which shows no significant pulsations but has a significant shift in the frequency correlations compared with other 3 non-pulsating atoll sources.
description: 21 pages, 8 Figures, submitted to ApJ
A Symmetric Multi-rod Tunable Microwave Cavity for the HAYSTAC Dark Matter Axion Search
Creators: name: Simanovskaia, Maria
name: Droster, Alex
name: Jackson, Heather
name: Urdinaran, Isabella
name: van Bibber, Karl
Publisher: name: arXiv
Year: 2020
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: The microwave cavity experiment is the most sensitive way of looking for axions in the 0.1-10 GHz range, corresponding to masses of 0.5 - 40 $μ$eV. The particular challenge for frequencies greater than 5 GHz is designing a cavity with a large volume that contains a resonant mode that has a high form factor, a high quality factor, a wide dynamic range, and is free from intruder modes. For HAYSTAC, we have designed and constructed an optimized high frequency cavity with a tuning mechanism that preserves a high degree of rotational symmetry, critical to maximizing its figure of merit. This cavity covers an important frequency range according to recent theoretical estimates for the axion mass, 5.5 - 7.4 GHz, and the design appears extendable to higher frequencies as well. This paper will discuss key design and construction details of the cavity, present a summary of the design evolution, and alert practitioners of potentially unfruitful avenues for future work.
description: 26 pages, 11 figures
Presentations of higher dimensional Thompson groups
Creators: name: Brin, Matthew G.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Group Theory (math.GR)
subject: FOS: Mathematics
subject: 20F05 (Primary), 20M05, 20B27, 20E32, 20F55, 57S25 (Secondary)

description: In a previous paper, we defined a higher dimensional analog of Thompson's group V, and proved that it is simple, infinite, finitely generated, and not isomorphic to any of the known Thompson groups. There are other Thompson groups that are infinite, simple and finitely presented. Here we show that the new group is also finitely presented by calculating an explicit finite presentation.
description: 35 pages, to appear in J. Algebra
Baryonic triplet P-wave dominant superfluidity under combined pion condensation with delta-mixing
Creators: name: Tamagaki, R.
name: Takatsuka, T.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We study baryonic superfluidity under the combined pion condensation with delta-mixing, where both condensates of the neutral and charged pions take place in neutron stars. Outline of formulation treating such superfluidity is presented and energy gap calculations show the possibility that critical temperatures are higher than about 1x10^9 K.
description: 6 pages,2 figures. To be published in Prog. Theor. Phys
Time-domain properties of electromagnetic signals in a dynamical axion background
Creators: name: Adshead, Peter
name: Draper, Patrick
name: Lillard, Benjamin
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Electromagnetic waves in a dynamical axion background exhibit superluminal group velocities at high frequencies and instabilities at low frequencies, altering how photons propagate through space. Local disturbances propagate causally, but unlike in ordinary Maxwell theory, propagation occurs inside as well as on the lightcone. For the unstable modes, the energy density in the electromagnetic field grows exponentially along timelike displacements. In this paper we derive retarded Green functions in axion electrodynamics in various limits and study the time-domain properties of propagating signals.
description: 24 pages, 6 figures, 2 appendices
Critical aging of a ferromagnetic system from a completely ordered state
Creators: name: Fedorenko, Andrei A.
name: Trimper, Steffen
Publisher: name: arXiv
Year: 2005
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We adapt the non-linear $σ$ model to study the nonequilibrium critical dynamics of O(n) symmetric ferromagnetic system. Using the renormalization group analysis in $d=2+ε$ dimensions we investigate the pure relaxation of the system starting from a completely ordered state. We find that the average magnetization obeys the long-time scaling behavior almost immediately after the system starts to evolve while the correlation and response functions demonstrate scaling behavior which is typical for aging phenomena. The corresponding fluctuation-dissipation ratio is computed to first order in $ε$ and the relation between transverse and longitudinal fluctuations is discussed.
description: 5 pages, revtex4
Dust size and spatial distributions in debris discs: predictions for exozodiacal dust dragged in from an exo-Kuiper belt
Creators: name: Rigley, Jessica K.
name: Wyatt, Mark C.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: The SEDs of some nearby stars show mid-infrared excesses from warm habitable zone dust, known as exozodiacal dust. This dust may originate in collisions in a planetesimal belt before being dragged inwards. This paper presents an analytical model for the size distribution of particles at different radial locations in such a scenario, considering evolution due to destructive collisions and Poynting-Robertson (P-R) drag. Results from more accurate but computationally expensive numerical simulations of this process are used to validate the model and fit its free parameters. The model predicts 11 $μ$m excesses ($R_{11}$) for discs with a range of dust masses and planetesimal belt radii using realistic grain properties. We show that P-R drag should produce exozodiacal dust levels detectable with the Large Binocular Telescope Interferometer (LBTI) ($R_{11} > 0.1\%$) in systems with known outer belts; non-detection may indicate dust depletion, e.g. by an intervening planet. We also find that LBTI could detect exozodiacal dust dragged in from a belt too faint to detect at far-infrared wavelengths, with fractional luminosity $f\sim 10^{-7}$ and radius $\sim 10-80$ au. Application to systems observed with LBTI shows that P-R drag can likely explain most (5/9) of the exozodiacal dust detections in systems with known outer belts; two systems ($β$ Uma and $η$ Corvi) with bright exozodi may be due to exocomets. We suggest that the three systems with exozodiacal dust detections but no known belt may have cold planetesimal belts too faint to be detectable in the far-infrared. Even systems without outer belt detections could have exozodiacal dust levels $R_{11} > 0.04\%$ which are problematic for exo-Earth imaging.
description: 25 pages, 20 figures, 2 tables. Accepted for publication in MNRAS
Consumer Panelist Behavior in Experimental Auctions: What Do We Learn From Their Bids?
Creators: name: Umberger, Wendy J.
name: Feuz, Dillon M.
name: Umberger, Wendy J.
name: Feuz, Dillon M.
Publisher: name: Unknown
Year: 2001
Subjects: Demand and Price Analysis

description: Experimental economics procedures such as laboratory experimental auctions are increasingly being used to measure consumers' willingness-to-pay. A sealed-bid, fourth-price Vickrey-style auction was used to measure consumers' willingness-to-pay for flavor in beef steaks. Two hundred and forty-eight consumers from Chicago and San Francisco participated in the experimental auctions. The data gathered from these experimental auctions was then used to examine individual demand or utility in an experimental, uniform-price auction; and to analyze market demand and market price in an experimental auction when supply is fixed but demand varies. The results indicated that certain demographic variables may increase the probability that a participant wins or loses an experimental auction. The market price was found to be a function of the number of participants in a panel, as well as consumers' tastes and preferences. Changes in the market price of the auctions in the study appear to be more a function of the same factors that influence demand in the marketplace, rather than a wealth effect. Consumers in this research did appear to be expressing their true value for the auction product and the auction provided a valuable measure of consumers' WTP for flavor.
CAUSES OF RETAIL PRICE FIXITY: AN EMPIRICAL ANALYSIS
Creators: name: Richards, Timothy J.
name: Patterson, Paul M.
name: Richards, Timothy J.
name: Patterson, Paul M.
Publisher: name: Unknown
Year: 2002
Subjects: Demand and Price Analysis

description: Existing empirical studies do not provide a unifying explanation for retail price fixity. However, economic hysteresis, or the persistence of an economic phenomenon after its initial cause has disappeared, offers a general explanation. Estimates of an empirical model of retail-price hysteresis using store-level scanner data support our hypothesis.
Coupled Painlevé II Systems in Dimension 4 and the systems of type ${A_4}^{(1)}$
Creators: name: Sasano, Yusuke
Publisher: name: arXiv
Year: 2005
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: Primary 34M55, 34M45, Secondary 58F05, 32S65

description: We find and study coupled Painlevé II systems in dimension 4, which can be obtained by a degeneration from the systems of type ${A_4}^{(1)}$. We compare these systems with other types of coupled Painlevé II systems from the viewpoint of the local index. We also give the phase spaces for these systems.
description: This paper has been withdrawn by the author. 14 pages, 2 figures
Radiation hardness of GaAs: Cr and Si sensors irradiated by electron beam
Creators: name: Kruchonak, U.
name: El-Azm, S. Abou
name: Afanaciev, K.
name: Chelkov, G.
name: Demichev, M.
name: Gostkin, M.
name: Guskov, A.
name: Firu, E.
name: Kobets, V.
name: Leyva, A.
name: D
name: Nozdrin, A.
name: Porokhovoy, S.
name: Sheremetyeva, A.
name: Smolyanskiy, P.
name: Torres, A.
name: Tyazhev, A.
name: Tolbanov, O.
name: Zamyatin, N.
name: Zarubin, A.
name: Zhemchugov, A.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: The interest in using the radiation detectors based on high resistive chromium-compensated GaAs (GaAs:Cr) in high energy physics and others applied fields has been growing steadily due to its numerous advantages over others classical materials. High radiation hardness at room temperature stands out and needs to be systematically investigated. In this paper an experimental study of the effect of 20.9 MeV electrons generated by the LINAC-200 accelerator on some properties of GaAs:Cr based sensors is presented. In parallel, Si sensors were irradiated at the same conditions, measured and analyzed in order to perform a comparative study. The target sensors were irradiated with the dose up to 1.5 MGy. The current-voltage characteristics, resistivity, charge collection efficiency and their dependences on the bias voltage and temperature were measured at different absorbed doses. An analysis of the possible microscopic mechanisms leading to the observed effects in GaAs:Cr sensors is presented in the article.
description: Paper sent to journal "Nuclear Inst. and Methods in Physics Research, A"
SHOULD THE PUBLIC SECTOR CONDUCT GENOMICS R&D?
Creators: name: Naseem, Anwar
name: Oehmke, James F.
name: Naseem, Anwar
name: Oehmke, James F.
Publisher: name: Unknown
Year: 2002
Subjects: Research and Development/Tech Change/Emerging Technologies

description: The nature of the observed market structure and R&D competition in genomics research is used as the basis for a comparative analysis of research under a mixed oligopoly, pure oligopoly and monopoly when the timing of the innovation outcome is uncertain (as in an R&D race), the winner-take-all assumption is relaxed and the profits in later stages are a function of the R&D expenditures of prior stages. The sufficient conditions under which a mixed oligopoly performs more R&D than the pure oligopoly and monopoly markets are derived and are shown to be a function of a) that public firm's objective is strictly greater than in the winning state then in the losing state, b) profits for the winning and losing private firms in the private duopoly are equal, post innovation, and c) the objective function of the firms in the mixed duopoly are increasing in research faster than they are for firms in the other two cases. It is suggested that when these conditions are met, the public firm can play a role in increasing the level of research in genomics.