cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The Hanle and Zeeman Effects in Solar Spicules: A Novel Diagnostic Window on Chromospheric Magnetism
Creators: name: Bueno, J. Trujillo
name: Merenda, L.
name: Centeno, R.
name: Collados, M.
name: Degl'Innocenti, E. Landi
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: An attractive diagnostic tool for investigating the magnetism of the solar chromosphere is the observation and theoretical modeling of the Hanle and Zeeman effects in spicules, as shown in this letter for the first time. Here we report on spectropolarimetric observations of solar chromospheric spicules in the He I 10830 Åmultiplet and on their theoretical modeling accounting for radiative transfer effects. We find that the magnetic field in the observed (quiet Sun) spicular material at a height of about 2000 km above the visible solar surface has a strength of the order of 10 G and is inclined by approximately $35^{\circ}$ with respect to the local vertical direction. Our empirical finding based on full Stokes-vector spectropolarimetry should be taken into account in future magnetohydrodynamical simulations of spicules.
description: 12 pages and 2 figures
Bending laminations on convex hulls of anti-de Sitter quasicircles
Creators: name: Merlin, Louis
name: Schlenker, Jean-Marc
Publisher: name: arXiv
Year: 2020
Subjects: subject: Geometric Topology (math.GT)
subject: Differential Geometry (math.DG)
subject: FOS: Mathematics

description: Let $λ_-$ and $λ_+$ be two bounded measured laminations on the hyperbolic disk $\mathbb H^2$, which "strongly fill" (definition below). We consider the left earthquakes along $λ_-$ and $λ_+$, considered as maps from the universal Teichmüller space $\mathcal T$ to itself, and we prove that the composition of those left earthquakes has a fixed point. The proof uses anti-de Sitter geometry. Given a quasi-symmetric homeomorphism $u:{\mathbb RP}^1\to {\mathbb RP}^1$, the boundary of the convex hull in $AdS^3$ of its graph in ${\mathbb RP}^1\times{\mathbb RP}^1\simeq \partial AdS^3$ is the disjoint union of two embedded copies of the hyperbolic plane, pleated along measured geodesic laminations. Our main result is that any pair of bounded measured laminations that "strongly fill" can be obtained in this manner.
description: 16 pages
Fast Navigation in a Large Hilbert Space Using Quantum Optimal Control
Creators: name: Larrouy, Arthur
name: Patsch, Sabrina
name: Richaud, Rémi
name: Raimond, Jean-Michel
name: Brune, Michel
name: Koch, Christiane
name: Gleyzes, Sébastien
Publisher: name: Freie Universität Berlin
Year: 2020
Subjects: subject: Quantum control
subject: Quantum information processing
subject: Quantum information with atoms & light
subject: Quantum metrology
subject: Rydberg atoms & molecules
subject: 500 Naturwissenschaften und Mathematik::530 Physik::539 Moderne Physik

description: The precise engineering of quantum states, a basic prerequisite for technologies such as quantum-enhanced sensing or quantum computing, becomes more challenging with increasing dimension of the system Hilbert space. Standard preparation techniques then require a large number of operations or slow adiabatic evolution and give access to only a limited set of states. Here, we use quantum optimal control theory to overcome this problem and derive shaped radio-frequency pulses to experimentally navigate the Stark manifold of a Rydberg atom. We demonstrate that optimal control, beyond improving the fidelity of an existing protocol, also enables us to accurately generate a nonclassical superposition state that cannot be prepared with reasonable fidelity using standard techniques. Optimal control thus substantially enlarges the range of accessible states. Our joint experimental and theoretical work establishes quantum optimal control as a key tool for quantum engineering in complex Hilbert spaces.
GHz QKD at telecom wavelengths using up-conversion detectors
Creators: name: Thew, R. T.
name: Tanzilli, S.
name: Krainer, L.
name: Zeller, S. C.
name: Rochas, A.
name: Rech, I.
name: Cova, S.
name: Zbinden, H.
name: Gisin, N.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We have developed a hybrid single photon detection scheme for telecom wavelengths based on nonlinear sum-frequency generation and silicon single-photon avalanche diodes (SPADs). The SPAD devices employed have been designed to have very narrow temporal response, i.e. low jitter, which we can exploit for increasing the allowable bit rate for quantum key distribution. The wavelength conversion is obtained using periodically poled Lithium niobate waveguides (W/Gs). The inherently high efficiency of these W/Gs allows us to use a continuous wave laser to seed the nonlinear conversion so as to have a continuous detection scheme. We also present a 1.27GHz qubit repetition rate, one-way phase encoding, quantum key distribution experiment operating at telecom wavelengths that takes advantage of this detection scheme. The proof of principle experiment shows a system capable of MHz raw count rates with a QBER less than 2% and estimated secure key rates greater than 100 kbit/s over 25 km.
description: 12 pages, 7 figures
From Missing Links to New Records: A Series of Novel Polychlorine Anions
Creators: name: Voßnacker, Patrick
name: Keilhack, Thomas
name: Schwarze, Nico
name: Sonnenberg, Karsten
name: Seppelt, Konrad
name: Malischewski, Moritz
name: Riedel, Sebastian
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: Halogens
subject: Polychlorides
subject: Quantum-chemical calculations
subject: Halogen-bonding
subject: Structure elucidation
subject: 500 Naturwissenschaften und Mathematik::540 Chemie::546 Anorganische Chemie

description: Herein we report the synthesis and structural characterization of four novel polychloride compounds. The compounds [CCl(NMe2)2][Cl(Cl2)3] and [NPr4][Cl(Cl2)4] have been obtained from the reaction of the corresponding chloride salts with elemental chlorine at low temperature. They are the missing links in the series of polychloride monoanions [Cl(Cl)n]− (n=1–6). Additionally, the reaction of decamethylferrocene with elemental chlorine was studied yielding [Cp*2Fe]2[Cl20], which contains the largest known polychloride [Cl20]2− to date, and [Cp*2Fe][Cl(Cl2)4(HF)], which is the first example of a polychloride‐HF network stabilized by strong hydrogen and halogen bonding. All compounds have been characterized by single‐crystal X‐ray diffraction, Raman spectroscopy and quantum‐chemical calculations.
Perturbation theory in a framework of iteration methods
Creators: name: Ciftci, Hakan
name: Hall, Richard L.
name: Saad, Nasser
Publisher: name: arXiv
Year: 2005
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: In a previous paper (J. Phys. A 36, 11807 (2003)), we introduced the `asymptotic iteration method' for solving second-order homogeneous linear differential equations. In this paper, we study perturbed problems in quantum mechanics and we use the method to find the coefficients in the perturbation series for the eigenvalues and eigenfunctions directly, without first solving the unperturbed problem.
description: 13 pages
A TARGET CONSUMER PROFILE AND POSITIONING FOR PROMOTION OF A NEW LOCALLY BRANDED BEEF PRODUCT
Creators: name: Wolf, Marianne McGarry
name: Thulin, Andrew J.
name: Wolf, Marianne McGarry
name: Thulin, Andrew J.
Publisher: name: Unknown
Year: 2000
Subjects: Consumer/Household Economics

description: This research examines the consumer profile and positioning for a new locally branded beef product. The research involves 413 beef consumers in California. The target consumers for the new locally branded beef product are approximately one-third of beef consumers in the local area. They are older, married, and from higher dual-income households. The target consumers for the new locally branded beef product are likely to have purchased other branded beef products. Approximately one-half of the beef consumers indicated that they make their meat purchase decisions in the store. The characteristics of beef that are important to the consumers when purchasing beef are price, quality, and appearance of the beef. Therefore, competitive pricing, packaging that highlights the product, and point of purchase material that focuses on the brand concept are very important to the positioning and marketing of the new branded beef product.
AutoKnow: Self-Driving Knowledge Collection for Products of Thousands of Types
Creators: name: Dong, Xin Luna
name: He, Xiang
name: Kan, Andrey
name: Li, Xian
name: Liang, Yan
name: Ma, Jun
name: Xu, Yifan Ethan
name: Zhang, Chenwei
name: Zhao, Tong
name: Saldana, Gabriel Blanco
name: Deshpande, Saurabh
name: Manduca, Alexandre Michetti
name: Ren, Jay
name: Singh, Surender Pal
name: Xiao, Fan
name: Chang, Haw-Shiuan
name: Karamanolakis, Giannis
name: Mao, Yuning
name: Wang, Yaqing
name: Faloutsos, Christos
name: McCallum, Andrew
name: Han, Jiawei
Publisher: name: arXiv
Year: 2020
Subjects: subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: Can one build a knowledge graph (KG) for all products in the world? Knowledge graphs have firmly established themselves as valuable sources of information for search and question answering, and it is natural to wonder if a KG can contain information about products offered at online retail sites. There have been several successful examples of generic KGs, but organizing information about products poses many additional challenges, including sparsity and noise of structured data for products, complexity of the domain with millions of product types and thousands of attributes, heterogeneity across large number of categories, as well as large and constantly growing number of products. We describe AutoKnow, our automatic (self-driving) system that addresses these challenges. The system includes a suite of novel techniques for taxonomy construction, product property identification, knowledge extraction, anomaly detection, and synonym discovery. AutoKnow is (a) automatic, requiring little human intervention, (b) multi-scalable, scalable in multiple dimensions (many domains, many products, and many attributes), and (c) integrative, exploiting rich customer behavior logs. AutoKnow has been operational in collecting product knowledge for over 11K product types.
description: KDD 2020
All Higher Genus BPS Membranes in the Plane Wave Background
Creators: name: Bak, Dongsu
name: Kim, Seok
name: Lee, Kimyeong
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider supermembranes in the maximally supersymmetric plane wave geometry of the eleven dimensions and construct complete solutions of the continuum version of the 1/4 BPS equations. The supermembranes may have an arbitrary number of holes and arbitrary cross sectional shapes. In the matrix regularized version, we solve the matrix equations for several simple cases including fuzzy torus. In addition, we show that these solutions are trivially generalized to 1/8 and 1/16 BPS configuations.
description: 14 pages, 5 figures, references, comments added
Discrete Hilbert Space, the Born Rule, and Quantum Gravity
Creators: name: Hsu, Stephen D. H.
Publisher: name: arXiv
Year: 2020
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Quantum gravitational effects suggest a minimal length, or spacetime interval, of order the Planck length. This in turn suggests that Hilbert space itself may be discrete rather than continuous. One implication is that quantum states with norm below some very small threshold do not exist. The exclusion of what Everett referred to as maverick branches is necessary for the emergence of the Born Rule in no collapse quantum mechanics. We discuss this in the context of quantum gravity, showing that discrete models (such as simplicial or lattice quantum gravity) indeed suggest a discrete Hilbert space with minimum norm. These considerations are related to the ultimate level of fine-graining found in decoherent histories (of spacetime geometry plus matter fields) produced by quantum gravity.
description: 10 pages, 1 figure
MODELING THE SUPPLY CHAIN USING MULTI-TIERED CAUSAL ANALYSIS
Creators: name: Chase, Charles W.
name: Chase, Charles W.
Publisher: name: Unknown
Year: 2000
Subjects: Agribusiness

description: Multi-tiered causal analysis is not really a technique but rather a procedure or process that models the push/pull effects of the supply chain by linking a series of multiple regression models together, based on marketing investment strategies and trade investments to retailers. The conceptual design applies in-depth causal analysis to measure the effects of the marketing mix on consumer demand at retail (pull-consumption/retail sell-through) and links it, via consumer demand, to shipments from the manufacturer (push) to the retailers. This situation is known as a two-tiered model. In the case of more sophisticated distribution systems, a model of three tiers (or more) can be deployed-incorporating, for example, wholesalers (that is, consumer to retailer to wholesaler to manufacturing plant).
Integration of geospatial data for mapping variation of sediment thickness in the North Sea
Creators: name: Lemenkova, Polina
Publisher: name: figshare
Year: 2020
Subjects: subject: Ecology
subject: FOS: Biological sciences
subject: 50206 Environmental Monitoring
subject: FOS: Earth and related environmental sciences
subject: 40201 Exploration Geochemistry
subject: Environmental Science
subject: 50205 Environmental Management
subject: 50203 Environmental Education and Extension
subject: 40104 Climate Change Processes
subject: 40502 Chemical Oceanography
subject: 40301 Basin Analysis
subject: Geophysics
subject: Geology
subject: 90901 Cartography
subject: FOS: Environmental engineering
subject: 80103 Computer Graphics
subject: FOS: Computer and information sciences

description: The study presents geospatial analysis of the seabed distribution of North Sea sediments. Data include thematic datasets with a high-resolution: GlobSed 5-arc-minute total sediment thickness grid combined with GEBCO regional bathymetric grid and geophysical grids showing EGM2008 geoid undulations and marine free-air gravity. The data have been processed using GMT. The data analysis revealed variations in the occurrence and distribution of sediment materials as well as its relationship with topography and regional geophysical settings, marine free-air gravity and geoid. Analysis of the topographic map was performed to describe the structural features of the seafloor. Ridges, large-scale sandbanks, shallow coastal areas and local depressions illustrate uneven bathymetry with northward increasing depths. The highest recorded value is 12,779.642 m located in the northern ares in the SW coast of Norway. Moderate values of sediment thickness (5,000-6,000 m) stretching in NW direction clearly correlate with the marine gravity anomaly isolines with values 10-20 mGal which points at the local relief forms in central basin of the North Sea. The subsidence of the outer shelf of the North Sea and increase of sediment thickness is notable in the central depressions and northern areas: Faroe Islands and Rockall Plateau. The sediment thickness shows the relationship with the topography increasing toward high latitudes. It is also associated with the isostatic sink of the submarine relief in the peripheral areas of the Arctic Ocean. Topographic compensation for the seafloor subsidence by increasing sediment thickness explains local dislocations connected with submarine geomorphology. This study also demonstrated that accurate GMT-based cartographic visualization of the oceanic seafloor using high-resolution multi-source raster grids is crucial to better understand spatial distribution of the marine sediments in the northern latitudes of the North Atlantic Ocean.
[Letter from Camille Sauvageau]
Creators: name: Sauvageau, Camille
Publisher: name: Unknown
Year: 1906

description: The algae she has sent was collected in the littoral zone at Puorto-Orotava (Tenerife). She is grateful for the information about the name Lithothamnion dentatum from Cadix. Has sent a specimen of L. dentatum which has another alga on it, maybe that called Goniolithon notarisii. Expresses gratitude for the papers on Lithothamnion which are very useful.
A Langevin dynamics approach for multi-layer mass transfer problems
Creators: name: Farago, Oded
name: Pontrelli, Giuseppe
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Medical Physics (physics.med-ph)
subject: FOS: Physical sciences

description: We use Langevin dynamics simulations to study the mass diffusion problem across two adjacent porous layers of different transport property. At the interface between the layers, we impose the Kedem-Katchalsky (KK) interfacial boundary condition that is well suited in a general situation. A detailed algorithm for the implementation of the KK interfacial condition in the Langevin dynamics framework is presented. As a case study, we consider a two-layer diffusion model of a drug-eluting stent. The simulation results are compared with those obtained from the solution of the corresponding continuum diffusion equation, and an excellent agreement is shown.
description: Accepted for publication in Computers in Biology and Medicine
Two-dimensional radiation-hydrodynamic model for limit-cycle oscillations of luminous accretion disks
Creators: name: Ohsuga, K.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We investigate the time evolution of luminous accretion disks around black holes, conducting the two-dimensional radiation-hydrodynamic simulations. We adopt the alpha prescription for the viscosity. The radial-azimuthal component of viscous stress tensor is assumed to be proportional to the total pressure in the optically thick region, while the gas pressure in the optically thin regime. The viscosity parameter, alpha, is taken to be 0.1. We find the limit-cycle variation in luminosity between high and low states. When we set the mass input rate from the outer disk boundary to be 100 L_E/c^2, the luminosity suddenly rises from 0.3L_E to 2L_E, where L_E is the Eddington luminosity. It decays after retaining high value for about 40 s. Our numerical results can explain the variation amplitude and duration of the recurrent outbursts observed in microquasar, GRS 1915+105. We show that the multi-dimensional effects play an important role in the high-luminosity state. In this state, the outflow is driven by the strong radiation force, and some part of radiation energy dissipated inside the disk is swallowed by the black hole due to the photon-trapping effects. This trapped luminosity is comparable to the disk luminosity. We also calculate two more cases: one with a much larger accretion rate than the critical value for the instability and the other with the viscous stress tensor being proportional to the gas pressure only even when the radiation pressure is dominant. We find no quasi-periodic light variations in these cases. This confirms that the limit-cycle behavior found in the simulations is caused by the disk instability.
description: 6 pages, 4 figures, accepted for publication in ApJ (ApJ 01 April 2006, v640, 2 issue)
An Application of Bessel function for Solving Nonlinear Fredholm-Volterra-Hammerstein Integro-differential Equations
Creators: name: Ordokhani, Yadollah
name: Dehestani, Haniye
Publisher: name: figshare
Year: 2020
Subjects: subject: 80202 Applied Discrete Mathematics
subject: FOS: Computer and information sciences

description: In this paper, a collocation method based on the Bessel polynomials is used for the solution of nonlinear Fredholm-Volterra-Hammerstein integro-differential equations
(FVHIDEs) under mixed conditions. This method of estimating the solution, transforms the nonlinear (FVHIDEs) to matrix equations with the help of Bessel polynomials of the first kind and collocation points. The matrix equations correspond to a system of nonlinear algebraic equations with the unknown Bessel coefficients. Present results and comparisons demonstrate that our estimate has good degree of accuracy and this method is more valid
and useful than other methods.
BORROWER PREFERENCES IN THE AGRICULTURAL CREDIT MARKET: A CONJOINT ANALYSIS
Creators: name: Bard, Sharon K.
name: Craig, Dawn J.
name: Boehlje, Michael
name: Bard, Sharon K.
name: Craig, Dawn J.
name: Boehlje, Michael
Publisher: name: Unknown
Year: 2002
Subjects: Agricultural Finance

description: The purpose of this study is to identify the attributes that farm borrowers value in the credit relationship as well as the trade-offs in those attributes. Agricultural borrowers prefer a lender who can provide them with competitive interest rates, quick decisions on a loan request, an adequate loan amount, and knowledge of the agricultural industry. Farm borrowers do not place a priority on customized terms, but they do expect a competitive interest rate and are unwilling to pay a higher interest rate in exchange for other attributes such as faster loan decisions or specialization in agricultural lending.
Learning Variational Data Assimilation Models and Solvers
Creators: name: Fablet, Ronan
name: Chapron, Bertrand
name: Drumetz, Lucas.
name: Memin, Etienne
name: Pannekoucke, Olivier
name: Rousseau, Francois
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Machine Learning (cs.LG)
subject: Atmospheric and Oceanic Physics (physics.ao-ph)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: This paper addresses variational data assimilation from a learning point of view. Data assimilation aims to reconstruct the time evolution of some state given a series of observations, possibly noisy and irregularly-sampled. Using automatic differentiation tools embedded in deep learning frameworks, we introduce end-to-end neural network architectures for data assimilation. It comprises two key components: a variational model and a gradient-based solver both implemented as neural networks. A key feature of the proposed end-to-end learning architecture is that we may train the NN models using both supervised and unsupervised strategies. Our numerical experiments on Lorenz-63 and Lorenz-96 systems report significant gain w.r.t. a classic gradient-based minimization of the variational cost both in terms of reconstruction performance and optimization complexity. Intriguingly, we also show that the variational models issued from the true Lorenz-63 and Lorenz-96 ODE representations may not lead to the best reconstruction performance. We believe these results may open new research avenues for the specification of assimilation models in geoscience.
De Sitter and double irregular domain walls
Creators: name: Guerrero, Rommel
name: Rodriguez, R. Omar
name: Ortiz, R.
name: Torrealba, Rafael
Publisher: name: arXiv
Year: 2005
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: A new method to obtain thick domain wall solutions to the coupled Einstein scalar field system is presented. The procedure allows the construction of irregular walls from well known ones, such that the spacetime associated to them are physically different. As consequence of the approach, we obtain two irregular geometries corresponding to thick domain walls with $dS$ expansion and topological double kink embedded in $AdS$ spacetime. In particular, the double brane can be derived from a fake superpotential.
description: 13 pages, 4 figures, added references, some equations corrected
Widening of Hydrous Shear Zones During Incipient Eclogitization of Metastable Dry and Rigid Lower Crust—Holsnøy, Western Norway
Creators: name: Kaatz, Lisa
name: Zertani, Sascha
name: Moulas, Evangelos
name: John, Timm
name: Labrousse, Loïc
name: Schmalholz, Stefan M.
name: Andersen, Torgeir B.
Publisher: name: Freie Universität Berlin
Year: 2021
Subjects: subject: eclogitization
subject: fluid‐induced weakening
subject: fluid‐rock interaction
subject: shear zone widening
subject: 500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie::551 Geologie, Hydrologie, Meteorologie

description: The partially eclogitized crustal rocks on Holsnøy in the Bergen Arcs, Norway, indicate that eclogitization is caused by the interplay of brittle and ductile deformation promoted by fluid infiltration and fluid‐rock interaction. Eclogitization generated an interconnected network of millimeter‐to‐kilometer‐wide hydrous eclogite‐facies shear zones, which presumably caused transient weakening of the mechanically strong lower crust. To decipher the development of those networks, we combine detailed lithological and structural mapping of two key outcrops with numerical modeling. Both outcrops are largely composed of preserved granulite with minor eclogite‐facies shear zones, thus representing the beginning phases of eclogitization and ductile deformation. We suggest that deformation promoted fluid‐rock interaction and eclogitization, which gradually consumed the granulite until fluid‐induced reactions were no longer significant. The shear zones widen during progressive deformation. To identify the key parameters that impact shear zone widening, we generated scale‐independent numerical models, which focus on different processes affecting the shear zone evolution: (i) rotation of the shear zones caused by finite deformation, (ii) mechanical weakening due to a limited amount of available fluid, and (iii) weakening and further hydration of the shear zones as a result of continuous and unlimited fluid supply. A continuous diffusion‐type fluid infiltration, with an effective diffusion coefficient around urn:x-wiley:02787407:media:tect21471:tect21471-math-0001, coupled with deformation is prone to develop structures similar to the ones mapped in field. Our results suggest that the shear zones formed under a continuous fluid supply, causing shear zone widening, rather than localization, during progressive deformation.
CHARACTERISTICS OF U.S. VEAL CONSUMERS
Creators: name: Henderson, Jason R.
name: Foster, Kenneth A.
name: Henderson, Jason R.
name: Foster, Kenneth A.
Publisher: name: Unknown
Year: 2000
Subjects: Consumer/Household Economics
Food Consumption/Nutrition/Food Safety

description: In response to a steady decline in U.S. veal consumption, veal producers have responded by searching for new demand opportunities. Results from descriptive analysis and a probit model of veal consumer characteristics indicates that veal is typically consumed away from home by an older, caucasian, male professional living in a metropolitan area in the Northeast. Promotion programs targeting this demographic group may provide limited gains. Promotion strategies that target consumers in other geographic regions and demographic groups for at home consumption could potentially lead to larger gains in veal consumption.
Atomic spin decoherence near conducting and superconducting films
Creators: name: Scheel, Stefan
name: Rekdal, Per-Kristian
name: Knight, Peter L.
name: Hinds, Edward A.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We derive scaling laws for the spin decoherence of neutral atoms trapped near conducting and superconducting plane surfaces. A new result for thin films sheds light on the measurement of Y.J. Lin, I. Teper, C. Chin, and V. Vuletić [Phys. Rev. Lett. \textbf{92}, 050404 (2004)]. Our calculation is based on a quantum-theoretical treatment of electromagnetic radiation near metallic bodies [P.K. Rekdal, S. Scheel, P.L. Knight, and E.A. Hinds, Phys. Rev. A \textbf{70}, 013811 (2004)]. We show that there is a critical atom-surface distance that maximizes the spin relaxation rate and we show how this depends on the skin depth and thickness of the metal surface. In the light of this impedance-matching effect we discuss the spin relaxation to be expected above a thin superconducting niobium layer.
description: 4 pages, 3 figures, typeset using RevTeX
A Brief Survey of the Monastery of St. George in Hanzt'a (mit Abbildungen)
Creators: name: Djobadze, Wachtang Zizischwili
Publisher: name: Oriens christianus : Hefte für die Kunde des christlichen Orients
Year: 2024

description: Oriens christianus : Hefte für die Kunde des christlichen Orients, Bd. 78 (1994): Oriens christianus, Band 78
Phase protection of Fano-Feshbach resonances
Creators: name: Blech, Alexander
name: Shagam, Yuval
name: Hölsch, Nicolas
name: Paliwal, Prerna
name: Skomorowski, Wojciech
name: Rosenberg, John W.
name: Bibelnik, Natan
name: Heber, Oded
name: Reich, Daniel M.
name: Narevicius, Edvardas
name: Koch, Christiane P.
Publisher: name: Freie Universität Berlin
Year: 2020
Subjects: subject: Atomic and molecular collision processes
subject: Excited states
subject: Imaging techniques
subject: Quantum mechanics
subject: 500 Naturwissenschaften und Mathematik::530 Physik::539 Moderne Physik

description: Decay of bound states due to coupling with free particle states is a general phenomenon occurring at energy scales from MeV in nuclear physics to peV in ultracold atomic gases. Such a coupling gives rise to Fano-Feshbach resonances (FFR) that have become key to understanding and controlling interactions—in ultracold atomic gases, but also between quasiparticles, such as microcavity polaritons. Their energy positions were shown to follow quantum chaotic statistics. In contrast, their lifetimes have so far escaped a similarly comprehensive understanding. Here, we show that bound states, despite being resonantly coupled to a scattering state, become protected from decay whenever the relative phase is a multiple of π. We observe this phenomenon by measuring lifetimes spanning four orders of magnitude for FFR of spin–orbit excited molecular ions with merged beam and electrostatic trap experiments. Our results provide a blueprint for identifying naturally long-lived states in a decaying quantum system.
TECHNOLOGICAL LEADERSHIP, HUMAN CAPITAL AND ECONOMIC GROWTH: A SPATIAL ECONOMETRIC ANALYSIS FOR U.S. COUNTIES, 1969-2003*
Creators: name: Pede, Valerien O.
name: Florax, Raymond J.G.M.
name: De Groot, Henri L.F.
name: Pede, Valerien O.
name: Florax, Raymond J.G.M.
name: De Groot, Henri L.F.
Publisher: name: Unknown
Year: 2006
Subjects: Community/Rural/Urban Development

description: The traditional view of cities as monocentric conglomerates of people clustered around an employment center, driving economic growth in cities that subsequently trickles down to the hinterland, is increasingly being challenged. In particular, the role of space, technological leadership, human capital, increasing returns to scale and industrial clustering as well as hierarchical organization principles have been emphasized in the more recent literature. This paper utilizes exploratory and spatial econometric data analysis techniques to investigate these issues for U.S. counties using data from 1969 through 2003. Ultimately, contiguous and hierarchical organization and interaction patterns are captured using an endogenous growth model allowing for spatial effects, inspired by earlier work on human capital and technology gaps. We investigate a neoclassical growth model and compare it to a spatial version of an endogenous growth model allowing for "domestic" investment in human capital and catch-up to the technology leader, and find that human capital strongly contributes to growth in a neoclassical setting, but much less so in an endogenous setting. In the endogenous model the catch-up term dominates in comparison to "domestic" human capital effects.
Linear instability and statistical laws of physics
Creators: name: Casati, Giulio
name: Tsallis, Constantino
name: Baldovin, Fulvio
Publisher: name: arXiv
Year: 2005
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We show that a meaningful statistical description is possible in conservative and mixing systems with zero Lyapunov exponent in which the dynamical instability is only linear in time. More specifically, (i) the sensitivity to initial conditions is given by $ ξ=[1+(1-q)λ_q t]^{1/(1-q)}$ with $q=0$; (ii) the statistical entropy $S_q=(1-\sum_i p_i^q)/(q-1) (S_1=-\sum_i p_i \ln p_i)$ in the infinitely fine graining limit (i.e., $W\equiv$ {\it number of cells into which the phase space has been partitioned} $\to\infty$), increases linearly with time only for $q=0$; (iii) a nontrivial, $q$-generalized, Pesin-like identity is satisfied, namely the $\lim_{t \to \infty} \lim_{W \to \infty} S_0(t)/t=\max\{λ_0\}$. These facts (which are in analogy to the usual behaviour of strongly chaotic systems with $q=1$), seem to open the door for a statistical description of conservative many-body nonlinear systems whose Lyapunov spectrum vanishes.
description: 7 pages including 2 figures. The present version is accepted for publication in Europhysics Letters
"Are they talking yet?" : online discourse as political action in an education policy forum
Creators: name: Klinger, Shulamit Sara
Publisher: name: University of British Columbia
Year: 2009

description: This thesis examines the dimensions of user engagement with an online forum on British Columbia's new policy on educational technology. Contributors to this site included elementary and secondary schoolteachers, distance educators, parents, students, researchers, BC Teachers' Federation staff and officers of the Ministry of Education. In the main, they did not respond to Ministry documents directly. Analysis of the site discussions reveals that participants mostly used the forum to debate the principles o f teaching and learning with technology. While many messages included collegial expressions of support, others revealed the political, ideological and pedagogical boundaries between the various education sectors in BC. In follow-up interviews, participants reported that the discussions were often fragmented and hard to follow, that it was virtually impossible to tell i f anyone else was listening, and what the impact of their contributions was. They were conscious of their professional status and uncomfortable about not knowing the size or identity of their audience, which included the Ministry of Education (BC). From the interview data I argue that the forum did not significantly increase public contributions to policy debate. However, while they acknowledged the shortcomings of the medium, participants still agreed that a forum of this kind was a valuable feature of their professional and political landscapes. In conclusion, I argue that different users differed enormously in their expectations of what the site offered, what their contribution might be and how such a site contributed to the realm of policy discussion at large. The political and educational agendas of those who did participate remained separate, fragmented and occasionally conflicting. The terms of engagement and motivation, as well as the shortcomings of this type of discussion, form the subject of this analysis. The conclusions reached here are critical to understanding the potential of this new medium for encouraging greater dialogue around political and professional issues in education and other fields. Finally, I argue that, i f the Ministry of Education could show a more effective listening presence, the texts which are produced on a future site would be more likely to answer their policy consultation needs.
Deterministic scale-free networks created in a recursive manner
Creators: name: Zhang, Zhongzhi
name: Rong, Lili
Publisher: name: arXiv
Year: 2005
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: In a recursive way and by including a parameter, we introduce a family of deterministic scale-free networks. The resulting networks exhibit small-world effects. We calculate the exact results for the degree exponent, the clustering coefficient and the diameter. The major points of our results indicate: the degree exponent can be adjusted; the clustering coefficient of each individual vertex is inversely proportional to its degree and the average clustering coefficient of all vertices approaches to a nonzero value in the infinite network order; and the diameter grows logarithmically with the number of network vertices.
description: 5 pages, 2 figures
بررسی پدیده سقف شیشه ای از دیدگاه جامعه شناسی سازمانی در سازمان های غیر دولتی ایران
Creators: name: Tavassoli, Afsaneh
name: Akbarian, Maryam
Publisher: name: figshare
Year: 2020
Subjects: subject: Sociology
subject: FOS: Sociology

description: هدف پروهش حاضر تحلیل پدیده سقف شیشه ای در سازمان های غیر دولتی ایران از دیدگاه جامعه شناسی سازمانی است. به همین دلیل چهار متغیر منشا قدرت سازمانی، ساختار کنش و واکنش سازمانی، فرهنگ جنسیتی سازمان، و باورهای شغلی وابسته به جنسیت به عنوان متغیر اصلی تحلیل مورد نظر قرار گرفت.و با ترکیب آن هشت فرضیه از نوع همبستگی صورت بندی گردید. همچنین از بین جامعه پژوهش با استفاده از روش نمونه گیری تصادفی ساده، 21 واحد دانشگاهی و تعداد 360 نفر عضو هیئت علمی به عنوان نمونه پژوهش برگزیده شدند.
Suppression of hole decoherence in ultrafast photoionization
Creators: name: Karamatskou, Antonia
name: Goetz, R. Esteban
name: Koch, Christiane
name: Santra, Robin
Publisher: name: Freie Universität Berlin
Year: 2020
Subjects: subject: Atomic & molecular processes in external fields
subject: Coherent control
subject: Multiphoton or tunneling ionization & excitation
subject: Single- and few-photon ionization & excitation
subject: Ultrafast phenomena
subject: 500 Naturwissenschaften und Mathematik::530 Physik::539 Moderne Physik

description: In simple one-photon ionization, decoherence occurs due to entanglement between ion and photoelectron. Therefore, the preparation of coherent superpositions of electronic eigenstates of the hole in the photoion is extremely difficult. We demonstrate for the xenon atom that the degree of electronic coherence of the photoion in attosecond photoionization can be enhanced if the influence of many-body interactions is properly controlled. A mechanism at low photon energies involving multiphoton ionization is found, suppressing the loss of coherence through ionization into the same photoelectron partial waves. The degree of coherence found between the 4 d0 and 5 s hole states is, on the one hand, limited by Auger decay of the 4 d0 hole. On the other hand, increasing the population ratio such that a significant portion of the state is in a true superposition of both states renders the maximization of the degree of coherence difficult.
THE FOOD AND AGRICULTURAL GLOBAL CARTELS OF THE 1990s: OVERVIEW AND UPDATE
Creators: name: Connor, John M.
name: Connor, John M.
Publisher: name: Unknown
Year: 2002
Subjects: Agribusiness

description: "Greed is good." --Gordon Gecko in Wall Street (1987) "Greed Is Bad." --Paul Krugman, The New York Times, June 4, 2002 "For many years, Archer Daniels Midland Co.'s philosophy of customer relations could be summed up by a quote from former ADM President James Randall: 'Our competitors are our friends. Our customers are the enemy.' This motto animated the company's business dealings and ultimately led to blatant violations of U.S. antitrust law, a guilty plea and a staggering criminal fine against the company . . . The facts involved in this case reflect an inexplicable lack of business ethics and an atmosphere of general lawlessness that infected the very heart of one of America's leading corporate citizens. Top executives at ADM and its Asian co-conspirators throughout the early 1990s spied on each other, fabricated aliases and front organizations to hide their activities, hired prostitutes to gather information from competitors, lied, cheated, embezzled, extorted, and obstructed justice." -- Decision of the U.S. Court of Appeals, 7th Circuit (Kanne et al. 2000:1-2) "Globalization can bring great benefits to consumers and business, but it can also cause harm, as evidenced by the rise in global cartels such as the vitamin cartel . . ." -- Senior official, Australian Competition and Consumer Commission, Business Weekly Review (December 13, 2001).
Random Lindblad equations from complex environments
Creators: name: Budini, Adrian A.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: In this paper we demonstrate that Lindblad equations characterized by a random rate variable arise after tracing out a complex structured reservoir. Our results follows from a generalization of the Born-Markov approximation, which relies in the possibility of splitting the complex environment in a direct sum of sub-reservoirs, each one being able to induce by itself a Markovian system evolution. Strong non-Markovian effects, which microscopically originate from the entanglement with the different sub-reservoirs, characterize the average system decay dynamics. As an example, we study the anomalous irreversible behavior of a quantum tunneling system described in an effective two level approximation. Stretched exponential and power law decay behaviors arise from the interplay between the dissipative and unitary hopping dynamics.
description: 11 pages, 4 figures, to be published in PRE
STRATEGY DEVELOPMENT IN A TURBULENT BUSINESS CLIMATE: CONCEPTS AND METHODS
Creators: name: Boehlje, Michael
name: Boehlje, Michael
Publisher: name: Unknown
Year: 2003
Subjects: Agribusiness
Risk and Uncertainty

description: The accelerating speed of change in the food and agribusiness industries is resulting in more risk and uncertainty - the future is becoming much less predictable. Not only is the future more uncertain, the drivers of that uncertainty are also changing - strategic risk which generally has a low probability of occurrence, but large consequences, is becoming an increasingly important component of the decision environment Managing these risks requires not only new assessment tools such as scorecarding and mapping, but also more systematic decision frameworks that can be best structured as decision trees. And managing time to redefine a strategic choice in an uncertain environment into a growth, divest, exit, pause or follow-on option that truncates the loss exposure and allows capture of the profit potential transforms strategy under uncertainty from a defensive posture of minimizing losses and protecting positions to an offensive posture of creating and capturing value
Surveying biomolecular frustration at atomic resolution
Creators: name: Chen, Mingchen
name: Chen, Xun
name: Schafer, Nicholas P.
name: Clementi, Cecilia
name: Komives, Elizabeth A.
name: Ferreiro, Diego U.
name: Wolynes, Peter G.
Publisher: name: Freie Universität Berlin
Year: 2020
Subjects: subject: Computational biophysics
subject: Drug discovery
subject: Protein folding
subject: 500 Naturwissenschaften und Mathematik::530 Physik::530 Physik
subject: 500 Naturwissenschaften und Mathematik::570 Biowissenschaften; Biologie::572 Biochemie

description: To function, biomolecules require sufficient specificity of interaction as well as stability to live in the cell while still being able to move. Thermodynamic stability of only a limited number of specific structures is important so as to prevent promiscuous interactions. The individual interactions in proteins, therefore, have evolved collectively to give funneled minimally frustrated landscapes but some strategic parts of biomolecular sequences located at specific sites in the structure have been selected to be frustrated in order to allow both motion and interaction with partners. We describe a framework efficiently to quantify and localize biomolecular frustration at atomic resolution by examining the statistics of the energy changes that occur when the local environment of a site is changed. The location of patches of highly frustrated interactions correlates with key biological locations needed for physiological function. At atomic resolution, it becomes possible to extend frustration analysis to protein-ligand complexes. At this resolution one sees that drug specificity is correlated with there being a minimally frustrated binding pocket leading to a funneled binding landscape. Atomistic frustration analysis provides a route for screening for more specific compounds for drug discovery.
Deep learning enhanced individual nuclear-spin detection
Creators: name: Jung, Kyunghoon
name: Abobeih, M. H.
name: Yun, Jiwon
name: Kim, Gyeonghun
name: Oh, Hyunseok
name: Ang, Henry
name: Taminiau, T. H.
name: Kim, Dohun
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The detection of nuclear spins using individual electron spins has enabled new opportunities in quantum sensing and quantum information processing. Proof-of-principle experiments have demonstrated atomic-scale imaging of nuclear-spin samples and controlled multi-qubit registers. However, to image more complex samples and to realize larger-scale quantum processors, computerized methods that efficiently and automatically characterize spin systems are required. Here, we realize a deep learning model for automatic identification of nuclear spins using the electron spin of single nitrogen-vacancy (NV) centers in diamond as a sensor. Based on neural network algorithms, we develop noise recovery procedures and training sequences for highly non-linear spectra. We apply these methods to experimentally demonstrate fast identification of 31 nuclear spins around a single NV center and accurately determine the hyperfine parameters. Our methods can be extended to larger spin systems and are applicable to a wide range of electron-nuclear interaction strengths. These results enable efficient imaging of complex spin samples and automatic characterization of large spin-qubit registers.
Do accretion discs regulate the rotation of young stars?
Creators: name: Littlefair, S. P.
name: Naylor, Tim
name: Burningham, Ben
name: Jeffries, R. D.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present a photometric study of I-band variability in the young cluster IC 348. The main purpose of the study was to identify periodic stars. In all we find 50 periodic stars, of which 32 were previously unknown. For the first time in IC 348, we discover periods in significant numbers of lower-mass stars (M < 0.25 Msun) and classical T-Tauri stars. This increased sensitivity to periodicities is due to the enhanced depth and temporal density of our observations, compared with previous studies. The period distribution is at first glance similar to that seen in the Orion Nebula Cluster, with the higher-mass stars (M > 0.25 Msun) showing a bi-modal period distribution concentrated around periods of 2 and 8 days, and the lower-mass stars showing a uni-modal distribution, heavily biassed towards fast rotators. Closer inspection of the period distribution shows that the higher mass stars show a significant dearth of fast rotators, compared to the Orion Nebula Cluster, whilst the low mass stars are rotating significantly faster than those in Orion. We find no correlation between rotation period and K-L colour or H-alpha equivalent width. We also present a discussion of our own IC 348 data in the context of previously published period distributions for the Orion Nebula Cluster, the Orion Flanking Fields and NGC 2264. We find that the previously claimed correlation between infrared excess and rotation period in the ONC might in fact result from a correlation between infrared excess and mass. We also find a marked difference in period distributions between NGC 2264 and IC 348, which presents a serious challenge to the disc locking paradigm, given the similarity in ages and disc fractions between the two clusters.
description: 13 pages, accepted for publication in MNRAS. Electronic data available at http://www.astro.ex.ac.uk/people/timn/Catalogues/description.html