cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Metallic transport of hard core bosons
Creators: name: Bhattacharyya, Sauri
name: De, Ayush
name: Gazit, Snir
name: Auerbach, Assa
Publisher: name: arXiv
Year: 2023
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Quantum Gases (cond-mat.quant-gas)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Conductivities and Hall coefficients of two dimensional hard core bosons are calculated using the thermodynamic expansions of Kubo formulas. At temperatures above the superfluid transition, the resistivity rises linearly and is weakly dependent on boson filling. The zeroth order Hall coefficient diverges toward zero and unit fillings, and reverses its sign at half filling. The correction terms, which are calculated up to fourth (Krylov) orders, do not alter this behavior. The high temperature thermal Hall coefficient is reversed relative to the electric Hall coefficient. We discuss relevance of HCB transport to the metallic state of short coherence length superconductors.
description: New version is a longer review paper
Feed-Grain Consumption by Traditional Pork-Producing Households in China
Creators: name: Fang, Cheng
name: Fuller, Frank H.
name: Fang, Cheng
name: Fuller, Frank H.
Publisher: name: Unknown
Year: 1998
Subjects: Livestock Production/Industries

description: Economic reforms in China's agricultural sector initiated in the late 1970s led to rapid structural change in China's pork sector. Swine production units have declined in number but increased in size. Using household survey data from seven provinces in China, feed-grain demand by pork producers is estimated for three different size categories: producers with annual pork output of less than 200 kg, between 200 kg and 500 kg, and greater than 500 kg. The results show that the households slaughtering one or two pigs each year are not market-oriented in their pork production. However, households producing more than 200 kg are quite price-responsive, especially households slaughtering more than five or six hogs each year. Wald tests for structural change indicate there is significant structural change as producers increase their scale of production and rely more heavily on markets for feed inputs.
Approach to realizing nonadiabatic geometric gates with prescribed evolution paths
Creators: name: Li, K. Z.
name: Zhao, P. Z.
name: Tong, D. M.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Nonadiabatic geometric phases are only dependent on the evolution path of a quantum system but independent of the evolution details, and therefore quantum computation based on nonadiabatic geometric phases is robust against control errors. To realize nonadiabatic geometric quantum computation, it is necessary to ensure that the quantum system undergoes a cyclic evolution and the dynamical phases are removed from the total phases. To satisfy these conditions, the evolution paths in previous schemes are usually restricted to some special forms, e.g, orange-slice-shaped loops, which make the paths unnecessarily long in general. In this paper, we put forward an approach to the realization of nonadiabatic geometric quantum computation by which a universal set of nonadiabatic geometric gates can be realized with any desired evolution paths. Our approach makes it possible to realize geometric quantum computation with an economical evolution time so the influence of environment noises on the quantum gates can be minimized further.
description: 6 pages, 2 figures
Computer technology in teacher education : tool for communication, medium for inquiry, object of critique
Creators: name: Mitchell, Jane Margaret
Publisher: name: University of British Columbia
Year: 2009

description: The central question in this thesis is: In what ways, if any, can communications technology be used to extend and integrate the learning and intellectual engagement of teacher education students? Underpinning this question is an assumption that there is a need to take action by way of investigating technology practices in teacher education programs that are educationally defensible. More particularly in the context of teacher education there is a need to examine ways in which the technology can be used as a medium for integrating disparate parts of teacher education and for broadening channels of professional communication amongst those with an interest in teacher education. In order to respond to the question a number of technology practices have been established in one elementary teacher education program. In this thesis three projects, representative of these practices, are presented. The three projects set in an Education Studies course, a Language Arts Education course and a Mathematics Education course respectively, used either web-based or multimedia technology as a medium through which students could communicate, investigate and generate ideas related to the course goals. The analysis of the projects was concerned with both the means by which students engaged in the technology related tasks and the ways in which they represented their understandings. The data drawn on to conduct this analysis included the electronic texts produced by students, the comments and feedback on each project provided by students and instructors and my own observational notes. The key argument made in the thesis is that the technology served as 1. a medium for inquiry and 2. an object of study. In this respect student teachers were able to extend their engagement by making connections between people, resources and experiences in ways not normally possible and by learning about educational technology in ways that were practical, creative and critical. The conditions underpinning these extensions to student teachers' learning were collaborative writing, public audience, access to electronic resources and a research infrastructure.
How crowd accidents are reported in the news media: Lexical and sentiment analysis
Creators: name: Feliciani, Claudio
name: Corbetta, Alessandro
name: Haghani, Milad
name: Nishinari, Katsuhiro
Publisher: name: arXiv
Year: 2023
Subjects: subject: Physics and Society (physics.soc-ph)
subject: FOS: Physical sciences

description: The portrayal of crowd accidents by the media can influence public understanding and emotional response, shaping societal perceptions and potentially impacting safety measures and preparedness strategies. This paper critically examines the portrayal of crowd accidents in news coverage by analyzing the texts of 372 media reports of crowd accidents spanning 26 diverse news sources from 1900 to 2019. We investigate how media representations of crowd accidents vary across time and geographical origins. Our methodology combines lexical analysis to unveil prevailing terminologies and sentiment analysis to discern the emotional tenor of the reports. The findings reveal the prevalence of the term "stampede" over "panic" in media descriptions of crowd accidents. Notably, divergent patterns are observable when comparing Western versus South Asian media (notably India and Pakistan), unveiling a cross-cultural dimension. Moreover, the analysis detects a gradual transition from "crowd stampede" to "crowd crush" in media and Wikipedia narratives in recent years, suggesting evolving lexical sensitivities. Sentiment analysis uncovers a consistent association with fear-related language, indicative of media's propensity towards sensationalism. This fear-infused narrative has intensified over time. The study underscores the potential impact of language and sentiment in shaping public perspectives on crowd accidents, revealing a pressing need for responsible and balanced reporting that moves beyond sensationalism and promotes a nuanced understanding. This will be crucial for increasing public awareness and preparedness against such accidents.
description: 54 pages, 15 figures, 17 tables, 4 appendixes, 372 media reports
Binding of eta_c meson with light nucleus
Creators: name: Belyaev, V. B.
name: Os'kin, A. F.
name: Sandhas, W.
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Binding energy of eta_c with ^4 He has been calculated on the basis of Yukawa type potential. Final Rank Approximation (FRA) has been used for microscopical treatment of the initial 5-body problem. The results are compared with the results of the folding model and variational calculations.
description: 5 pages, 1 figure
Business Organization and Coordination in Marketing Specialty Hogs: A Comparative Analysis of Two Firms from Iowa
Creators: name: Hueth, Brent
name: Ibarburu, Maro A.
name: Kliebenstein, James B.
name: Hueth, Brent
name: Ibarburu, Maro A.
name: Kliebenstein, James B.
Publisher: name: Unknown
Year: 2005
Subjects: subject: Livestock Production/Industries
subject: Specialty hogs
subject: coordination
subject: contracting
subject: organizational design
subject: niche markets

description: We study business organization and coordination of specialty-market hog production using a comparative analysis of two Iowa pork niche-marketing firms. We describe and analyze each firm's management of five key organizational challenges: planning and logistics, quality assurance, process verification and management of "credence attributes," business structure, and profit sharing. Although each firm is engaged in essentially the same activity, there are substantial differences across the two firms in the way production and marketing are coordinated. These differences are partly explained by the relative size and age of each firm, thus highlighting the importance of organizational evolution in agricultural markets, but are also partly the result of a formal organizational separation between marketing and production activities in one of the firms.
Mythimna obsoleta
Creators: name: Joos, R Enato
name: Fritsch, Dieter
name: Bryner, Rudolf
name: Billen, Wolfgang
name: Wicki, Christoph
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Lepidoptera
Noctuidae
Mythimna
Mythimna obsoleta

description: 10010 Mythimna obsoleta (Hübner, 1803)
Münchenstein (BL), Merian Gärten, 25.6.2014. In der Region gibt es nur wenige Nachweise. Die Art wandert und wird meist nur anhand einzelner Falter nachgewiesen.
description: Published as part of Joos, R Enato, Fritsch, Dieter, Bryner, Rudolf, Billen, Wolfgang & Wicki, Christoph, 2018, Vielfalt der nachtaktiven Gross- und Kleinschmetterlinge in zwei Parkanlagen bei Basel, pp. 57-71 in Entomo Helvetica 11 on page 63, DOI: 10.5169/seals-986024, http://zenodo.org/record/8034307
Activation and Protonation of Dinitrogen at the FeMo-Cofactor of Nitrogenase
Creators: name: Kaestner, Johannes
name: Hemmen, Sascha
name: Bloechl, Peter E.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Biomolecules (q-bio.BM)
subject: FOS: Biological sciences

description: The protonation of N2 bound to the active center of nitrogenase has been investigated using state-of-the-art DFT calculations. Dinitrogen in the bridging mode is activated by forming two bonds to Fe sites, which results in a reduction of the energy for the first hydrogen transfer by 123 kJ/mol. The axial binding mode with open sulfur bridge is less reactive by 30 kJ/mol and the energetic ordering of the axial and bridged binding mode is reversed in favor of the bridging dinitrogen during the first protonation. Protonation of the central ligand is thermodynamically favorable but kinetically hindered. If the central ligand is protonated, the proton is transferred to dinitrogen following the second protonation. Protonation of dinitrogen at the Mo site does not lead to low-energy intermediates.
description: 9 Pages, 6 figures, accepted in J. Chem. Phys. Typos corrected according to the galley proofs of JCP
What's the Use? Welfare Estimates from Revealed Preference Models when Weak Complementarity does not Hold
Creators: name: Herriges, Joseph A.
name: Kling, Catherine L.
name: Phaneuf, Daniel J.
name: Herriges, Joseph A.
name: Kling, Catherine L.
name: Phaneuf, Daniel J.
Publisher: name: Unknown
Year: 2000
Subjects: subject: Research Methods/ Statistical Methods
subject: Revealed preference
subject: valuation
subject: weak complementarity
subject: use value

description: The focal point of the revealed preference (RP) valuation literature, including recreation demand and random utility maximization (RUM) models, has been on eliciting the "use" value associated with environmental amenities; i.e., that portion of value associated with direct use of a resource. Maler's (1974) concept of weak complementarity is typically invoked to justify this focus. Indeed, weak complementarity explicitly or implicitly underlies most of the RP literature. In this paper, we consider the measurement of welfare in RP models when weak complementarity does not hold. In particular, the Kuhn-Tucker (KT) framework (e.g., Phaneuf et al. 2000) does not impose weak complementarity a priori, raising the possibility of rejecting weakly complementary in estimation and the question as to what is the proper welfare measure to report. Although existence value cannot be measured, we argue that in some circumstances there are components of total value outside of use value onto which RP methods may be able to shed light.
Applied nonrelativistic conformal field theory: scattering-length and effective-range corrections to unnuclear physics
Creators: name: Chowdhury, Subham Dutta
name: Mishra, Ruchira
name: Son, Dam Thanh
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Due to an accidentally large $s$-wave scattering length, in a relatively wide range of energy, neutrons are approximately described by the nonrelativistic conformal field theory of unitarity fermions, perturbed by one relevant and an infinite number of irrelevant operators. We develop a formalism which provides a nonperturbative definition of local operators in that nonrelativistic conformal field theory. We compute the scattering-length and effective-range corrections to the two-point functions of primary charge-three operators using the technique of conformal perturbation theory. These calculations allow us to find the first corrections to the scale-invariant behavior of the rate of nuclear reactions with three neutrons in the final state in the regime when the neutrons have small relative momenta.
description: 32 Pages, 4 tables
Subspace Identification of Linear Time-Periodic Systems with Periodic Inputs
Creators: name: Yin, Mingzhou
name: Iannelli, Andrea
name: Smith, Roy S.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Systems and Control (eess.SY)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: This paper proposes a new methodology for subspace identification of linear time-periodic (LTP) systems with periodic inputs. This method overcomes the issues related to the computation of frequency response of LTP systems by utilizing the frequency response of the time-lifted system with linear time-invariant structure instead. The response is estimated with an ensemble of input-output data with periodic inputs. This allows the frequency-domain subspace identification technique to be extended to LTP systems. The time-aliased periodic impulse response can then be estimated and the order-revealing decomposition of the block-Hankel matrix is formulated. The consistency of the proposed method is proved under mild noise assumptions. Numerical simulation shows that the proposed method performs better than multiple widely-used time-domain subspace identification methods when an ensemble of periodic data is available.
EOSC-hub D7.2 First report on Thematic Service architecture and software integration
Creators: name: Cacciari, Claudio
Publisher: name: Zenodo
Year: 2019

description: The current deliverable describes the activities done by the various tasks of the work package 7 (Thematic Services: Integration, maintenance and Exploitation) during the first year of the project. Each task represents a Thematic Service, which is a single service or a set provided by a research community for its users. In particular, the deliverable focuses its attention on the architecture of those services and on their integration within the EOSC-hub ecosystem
Irreversible Abatement Investment Under Cost Uncertainties: Tradable Emission Permits and Emissions Charges
Creators: name: Zhao, Jinhua
name: Zhao, Jinhua
Publisher: name: Unknown
Year: 2000
Subjects: Environmental Economics and Policy

description: A major concern with TEPs is that stochastic permit prices may reduce firm incentive to invest in abatement capital or technologies relative to other policies such as a fixed emissions charge. However, under effcient permit trading, the price uncertainty is caused by abatement cost uncertainties which affect investment under both permit and charge policies. We develop a rational expectations general equilibrium model of permit trading to show how cost uncertainty affects investment. Differences between the two policies can be decomposed into a general equilibrium effect and a price-vs-quantity effect. Except for the curvature of the payoff functions, uncertainties reduce both effects so that tradable permits in fact help maintain firms' investment incentive under uncertainty.
Nuclear models for inclusive lepton-nucleus scattering in the quasi-elastic region and beyond
Creators: name: Belocchi, Valerio
name: Barbaro, Maria Benedetta
name: De Pace, Arturo
name: Martini, Marco
Publisher: name: arXiv
Year: 2023
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: High-precision measurements in neutrino oscillation experiments require a very accurate description of the lepton-nucleus scattering process. Several cross-section calculations are available, but important discrepancies are still present between different model predictions. For the quasi-elastic channel, dominated by one particle-one hole excitations, an overview over several nuclear models - specifically Relativistic Fermi Gas, SuperScaling Approach, Spectral Function, Hartree-Fock and Random Phase Approximation - is presented and compared with data for electron-nucleus scattering, a very important process for testing theoretical models validity, highlighting the specific features of each approach. Furthermore an ongoing microscopic calculation of the two particle-two hole excitations contribution to the electromagnetic response is presented, and some preliminary results are shown.
Transmittivity measurements by means of squeezed vacuum light
Creators: name: D'Auria, V.
name: de Lisio, C.
name: Porzio, A.
name: Solimeno, S.
name: Paris, M. G. A.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: A method for measuring the transmittivity of optical samples by using squeezed--vacuum radiation is illustrated. A squeezed vacuum field generated by a below--threshold optical parametric oscillator is propagated through a nondispersive medium and detected by a homodyne apparatus. The variance of the detected quadrature is used for measuring the transmittivity. With this method it is drastically reduced the number of photons passing through the sample during the measurement interval. The results of some tests are reported.
description: 14 pages, 8 figures
Trikarenos: A Fault-Tolerant RISC-V-based Microcontroller for CubeSats in 28nm
Creators: name: Rogenmoser, Michael
name: Benini, Luca
Publisher: name: arXiv
Year: 2023
Subjects: subject: Hardware Architecture (cs.AR)
subject: FOS: Computer and information sciences

description: One of the key challenges when operating microcontrollers in harsh environments such as space is radiation-induced Single Event Upsets (SEUs), which can lead to errors in computation. Common countermeasures rely on proprietary radiation-hardened technologies, low density technologies, or extensive replication, leading to high costs and low performance and efficiency. To combat this, we present Trikarenos, a fault-tolerant 32-bit RISC-V microcontroller SoC in an advanced TSMC 28nm technology. Trikarenos alleviates the replication cost by employing a configurable triple-core lockstep configuration, allowing three Ibex cores to execute applications reliably, operating on ECC-protected memory. If reliability is not needed for a given application, the cores can operate independently in parallel for higher performance and efficiency. Trikarenos consumes 15.7mW at 250MHz executing a fault-tolerant matrix-matrix multiplication, a 21.5x efficiency gain over state-of-the-art, and performance is increased by 2.96x when reliability is not needed for processing, with a 2.36x increase in energy efficiency.
description: 4 pages, 4 figures, accepted by IEEE International Conference on Electronics Circuits and Systems (ICECS) 2023
Quantum Scalar Field Theory Based On Principle of Least Observability
Creators: name: Yang, Jianhao M.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Recently it is shown that the non-relativistic quantum formulations can be derived from a least observability principle [36]. In this paper, we apply the principle to massive scalar fields, and derive the Schrödinger equation of the wave functional for the scalar fields. The principle extends the least action principle in classical field theory by factoring in two assumptions. First, the Planck constant defines the minimal amount of action a field needs to exhibit in order to be observable. Second, there are constant random field fluctuations. A novel method is introduced to define the information metrics to measure additional observable information due to the field fluctuations, \added{which is then converted to the additional action through the first assumption.} Applying the variation principle to minimize the total actions allows us to elegantly derive the transition probability of field fluctuations, the uncertainty relation, and the Schrödinger equation of the wave functional. Furthermore, by defining the information metrics for field fluctuations using general definitions of relative entropy, we obtain a generalized Schrödinger equation of the wave functional that depends on the order of relative entropy. Our results demonstrate that the extended least action principle can be applied to derive both non-relativistic quantum mechanics and relativistic quantum scalar field theory. We expect it can be further used to obtain quantum theory for non-scalar fields.
description: 15 pages. Add journal reference. This is a companion paper to arXiv:2302.14619. It extends the applicability of the least observability principle introduced in arXiv:2302.14619 to quantum scalar field theory
Minimizing Acquisition Maximizing Inference -- A demonstration on print error detection
Creators: name: Shandilya, Suyash
Publisher: name: arXiv
Year: 2020
Subjects: subject: Image and Video Processing (eess.IV)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Is it possible to detect a feature in an image without ever looking at it? Images are known to have sparser representation in Wavelets and other similar transforms. Compressed Sensing is a technique which proposes simultaneous acquisition and compression of any signal by taking very few random linear measurements (M). The quality of reconstruction directly relates with M, which should be above a certain threshold for a reliable recovery. Since these measurements can non-adaptively reconstruct the signal to a faithful extent using purely analytical methods like Basis Pursuit, Matching Pursuit, Iterative thresholding, etc., we can be assured that these compressed samples contain enough information about any relevant macro-level feature contained in the (image) signal. Thus if we choose to deliberately acquire an even lower number of measurements - in order to thwart the possibility of a comprehensible reconstruction, but high enough to infer whether a relevant feature exists in an image - we can achieve accurate image classification while preserving its privacy. Through the print error detection problem, it is demonstrated that such a novel system can be implemented in practise.
GLOBAL AGRICULTURAL LIBERALIZATION: AN IN-DEPTH ASSESSMENT OF WHAT IS AT STAKE
Creators: name: Van Der Mensbrugghe, Dominique
name: Beghin, John C.
name: Van Der Mensbrugghe, Dominique
name: Beghin, John C.
Publisher: name: Unknown
Year: 2004
Subjects: subject: International Relations/Trade
subject: agricultural trade liberalization
subject: developing countries
subject: Doha Round
subject: farm policy
subject: WTO

description: We use the global Linkage model to assess the impact of trade and support policies in agriculture on income, trade, and output patterns. We provide order-of-magnitude estimates of the impacts of policy changes rather than point estimates. Two sets of simulations are used to identify key drivers in the results. One set decomposes the aggregate results by looking at the impacts of partial reforms, regionally and across instruments, to identify the relative contribution to global gains of reforms in industrialized and developing countries and of border protection versus domestic support. The second set responds to critics of trade reform (inflated gains for developing countries, no transition costs for industrial country farmers, uncertain supply response in developing countries). Reform of agriculture and food provides 70 percent of the global gains from merchandise trade reform of $385 billion. The global gains are shared equally among industrial and developing countries. Developing countries gain more as a share of initial income, and income gains occur in developing country agriculture, reducing poverty. Both groups of countries gain more from their own reforms than from the other group's reforms. Productivity and supply assumptions affect impact assessment, but their influence is small and does not alter the main aggregate findings. Trade elasticities, however, are key in determining the overall level of the income gains. Higher elasticities dampen terms-of-trade effects and increase trade and real income gains more than proportionally and the converse is true for smaller elasticities. These effects can be very large for individual countries.
Transverse force on a moving vortex with the acoustic geometry
Creators: name: Zhang, Peng-ming
name: Cao, Li-ming
name: Duan, Yi-shi
name: Zhong, Cheng-kui
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider the transverse force on a moving vortex with the acoustic metric using the $ϕ$-mapping topological current theory. In the frame of effective spacetime geometry the vortex appear naturally by virtue of the vortex tensor in the Lorentz spacetime and we show that it is just the vortex derived with the order parameter in the condensed matter. With the usual Lagrangian we obtain the equation of motion for the vortex. At last, we show that the transverse force on the moving vortex in our equation is just the usual Magnus force in a simple model.
description: 11 pages, no figure
Kagome KMn$_3$Sb$_5$ metal: Magnetism, lattice dynamics, and anomalous Hall conductivity
Creators: name: Singh, Sobhit
name: Garcia-Castro, A. C.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Kagome metals are reported to exhibit remarkable properties, including superconductivity, charge density wave order, and a large anomalous Hall conductivity, which facilitate the implementation of spintronic devices. In this work, we study a novel kagome metal based on Mn magnetic sites in a KMn$_3$Sb$_5$ stoichiometry. By means of first-principles density functional theory calculations, we demonstrate that the studied compound is dynamically stable, locking the ferromagnetic order as the ground state configuration, thus preventing the charge-density-wave state as reported in its vanadium-based counterpart KV$_3$Sb$_5$. Our calculations predict that KMn$_3$Sb$_5$ exhibits an out-of-plane (001) ferromagnetic response as the ground state, allowing for the emergence of topologically protected Weyl nodes near the Fermi level and nonzero anomalous Hall conductivity ($σ_{ij}$) in this centrosymmetric system. We obtain a tangible $σ_{xy} = 314$ S$\cdot$cm$^{-1}$ component, which is comparable to that of other kagome metals. Finally, we explore the effect of the on-site Coulomb repulsion ($+U$) on the structural and electronic properties and find that, although the lattice parameters and $σ_{xy}$ moderately vary with increasing $+U$, KMn$_3$Sb$_5$ stands as an ideal stable ferromagnetic kagome metal with a large anomalous Hall conductivity response.
Spin Polarization at Semiconductor Point Contacts in Absence of Magnetic Field
Creators: name: Eto, Mikio
name: Hayashi, Tetsuya
name: Kurotani, Yuji
Publisher: name: arXiv
Year: 2005
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Semiconductor point contacts can be a useful tool for producing spin-polarized currents in the presence of spin-orbit (SO) interaction. Neither magnetic fields nor magnetic materials are required. By numerical studies, we show that (i) the conductance is quantized in units of 2e^2/h unless the SO interaction is too strong, (ii) the current is spin-polarized in the transverse direction, and (iii) a spin polarization of more than 50% can be realized with experimentally accessible values of the SO interaction strength. The spin-polarization ratio is determined by the adiabaticity of the transition between subbands of different spins during the transport through the point contacts.
description: 4 pages, 4 figures; minor changes, published in J. Phys. Soc. Jpn
The sine-Gordon model from coupled condensates: a Generalized Hydrodynamics viewpoint
Creators: name: Bastianello, Alvise
Publisher: name: arXiv
Year: 2023
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Quantum Gases (cond-mat.quant-gas)
subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The sine-Gordon model captures the low-energy effective dynamics of a wealth of one-dimensional quantum systems, stimulating the experimental efforts in building a versatile quantum simulator of this field theory and fueling the parallel development of new theoretical toolkits able to capture far-from-equilibrium settings. In this work, we analyze the realization of sine-Gordon from the interference pattern of two one-dimensional quasicondensates: we argue the emergent field theory is well described by its classical limit and develop its large-scale description based on Generalized Hydrodynamics. We show how, despite sine-Gordon being an integrable field theory, trap-induced inhomogeneities cause instabilities of excitations and provide exact analytical results to capture this effect.
description: 21 pages, 7 figures
Flying doughnut terahertz pulses generated from semiconductor currents
Creators: name: Jana, Kamalesh
name: Mi, Yonghao
name: Møller, Søren H.
name: Ko, Dong Hyuk
name: Gholam-Mirzaei, Shima
name: Abdollahpour, Daryoush
name: Sederberg, Shawn
name: Corkum, Paul B.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: The ability to manipulate the space-time structure of light waves diversifies light-matter interaction and light-driven applications. Conventionally, metasurfaces are employed to locally control the amplitude and phase of light fields by the material response and structure of small meta-atoms. However, the fixed spatial structures of metasurfaces offer limited opportunities. Here, using quantum control we introduce a new approach that enables the amplitude, sign, and even configuration of the generated light fields to be manipulated in an all-optical manner. Following this approach, we demonstrate the generation of flying doughnut terahertz (THz) pulses. We show that the single-cycle THz pulse radiated from the dynamic semiconductor ring current has an electric field structure that is azimuthally polarized and that the space- and time-resolved magnetic field has a strong, isolated longitudinal component. As a first application, we detect absorption features from ambient water vapor on the spatiotemporal structure of the measured electric fields and the calculated magnetic fields. Quantum control is a powerful and flexible route to generating any structured light pulse in the THz range, while pulse compression of cylindrical vector beams is available for very high-power magnetic-pulse generation from the mid-infrared to near UV spectral region. Pulses such as these will serve as unique probes for spectroscopy, imaging, telecommunications, and magnetic materials.
Der Looping
Creators: name: Schröer, Harald
Publisher: name: Zenodo
Year: 2021
Subjects: Looping,senkrecht,geneigt, makro,Geschwindigkeit, Minimum,Aufgabe.Lösungen

description: Die Mindestgeschwindigkeit für Bahnen auf dem Looping wird betrachtet. Behandelt werden der senkrechte,der geneigte Looping. Außerdem folgt zuletzt der Makrolooping. Aufgaben mit Lösungen sind vorhanden.
Underlying mechanism of charge transfer in Li-doped MgH$_{16}$ at high pressure
Creators: name: Wang, Chongze
name: Yi, Seho
name: Cho, Jun-Hyung
Publisher: name: arXiv
Year: 2020
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: A lithium-doped magnesium hydride Li$_2$MgH$_{16}$ was recently reported [Y. Sun $et$ $al$., Phys. Rev. Lett. {\bf 123}, 097001 (2019)] to exhibit the highest ever predicted superconducting transition temperature $T_{\rm c}$ under high pressure. Based on first-principles density-functional theory calculations, we reveal that the Li dopants locating in the pyroclore lattice sites give rise to the excess electrons distributed in interstitial regions. Such loosely bound anionic electrons are easily captured to stabilize a clathrate structure consisting of H cages. This addition of anionic electrons to H cages enhances the H-derived electronic density of states at the Fermi level, thereby leading to a high-$T_{\rm c}$ superconductivity. We thus propose that the electride nature of Li dopants is an essential ingredient in the charge transfer between Li dopants and H atoms. Our findings offer a deeper understanding of the underlying mechanism of charge transfer in Li$_2$MgH$_{16}$ at high pressure.
QCD analyses of HERA cross section data
Creators: name: Gwenlan, C.
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: The H1 and ZEUS Collaborations have performed new next-to-leading order QCD analyses to determine the parton density functions of the proton. QCD fits are performed using inclusive neutral and charged deep inelastic scattering cross sections from HERA-I. The fits include a full treatment of experimental systematic uncertainties, taking into account point-to-point correlations. The extracted parton densities are in agreement with those from global fits. Since HERA inclusive data provide no direct information on the high-x gluon, an independent fit has been performed by the ZEUS Collaboration in which the inclusive cross sections are supplemented by jet data from neutral current deep inelastic scattering and photoproduction. The determination of the gluon distribution is significantly improved in such fits, allowing a competitive extraction of the strong coupling, alpha_s(MZ).
description: 5 pages,4 figures, on behalf of the ZEUS and H1 Collaborations, in proceedings of the 32nd International Conference on High Energy Physics - ICHEP04, Beijing, China, 2004
Search for GeV Gamma-Ray Emission from SPT-SZ selected Galaxy Clusters with 15 years of Fermi-LAT data
Creators: name: Manna, Siddhant
name: Desai, Shantanu
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Galaxy clusters could produce gamma-rays from inverse Compton scattering of cosmic ray electrons or hadronic interactions of cosmic ray protons with the intracluster medium. It is still an open question on whether gamma-ray emission ($>$ GeV energies) has been detected from galaxy clusters. We carry out a systematic search for gamma-ray mission based on 300 galaxy clusters selected from the 2500 deg.$^2$ SPT-SZ survey after sorting them in descending order of $M_{500}/z^2$, using about 15 years of Fermi-LAT data in the energy range between 1-300 GeV. We were able to detect gamma-ray emission with significance of about $6.1σ$ from one cluster, viz SPT-CL J2012-5649. The estimated photon energy flux from this cluster is approximately equal to $1.3 \times 10^{-6}$ MeV cm$^{-2}$ s$^{-1}$. The gamma-ray signal is observed between $1-10$ GeV with the best-fit spectral index equal to $-3.61 \pm 0.33$. However, since there are six radio galaxies spatially coincident with SPT-CL J2012-5649 within the Fermi-LAT PSF, we cannot rule out the possibility this signal could be caused by some of these radio galaxies. Six other SPT-SZ clusters show evidence for gamma-ray emission with significance between $3-5σ$. None of the remaining clusters show statistically significant evidence for gamma-ray emission.
description: 17 pages, 20 figures. Accepted for publication in JCAP
Improved $q$-values for discrete uniform and homogeneous tests: a comparative study
Creators: name: Cousido-Rocha, Marta
name: de Uña-Álvarez, Jacobo
name: Döhler, Sebastian
Publisher: name: arXiv
Year: 2020
Subjects: subject: Methodology (stat.ME)
subject: Computation (stat.CO)
subject: FOS: Computer and information sciences
subject: G.3

description: Large scale discrete uniform and homogeneous $P$-values often arise in applications with multiple testing. For example, this occurs in genome wide association studies whenever a nonparametric one-sample (or two-sample) test is applied throughout the gene loci. In this paper we consider $q$-values for such scenarios based on several existing estimators for the proportion of true null hypothesis, $π_0$, which take the discreteness of the $P$-values into account. The theoretical guarantees of the several approaches with respect to the estimation of $π_0$ and the false discovery rate control are reviewed. The performance of the discrete $q$-values is investigated through intensive Monte Carlo simulations, including location, scale and omnibus nonparametric tests, and possibly dependent $P$-values. The methods are applied to genetic and financial data for illustration purposes too. Since the particular estimator of $π_0$ used to compute the $q$-values may influence the power, relative advantages and disadvantages of the reviewed procedures are discussed. Practical recommendations are given.
CROP INSURANCE RATES AND THE LAWS OF PROBABILITY
Creators: name: Babcock, Bruce A.
name: Hart, Chad E.
name: Hayes, Dermot J.
name: Babcock, Bruce A.
name: Hart, Chad E.
name: Hayes, Dermot J.
Publisher: name: Unknown
Year: 2002
Subjects: Risk and Uncertainty

description: Increased crop insurance subsidies have increased the demand for insurance at coverage levels higher than the traditional level of 65 percent. Premium rates for higher levels of yield insurance under the Federal Actual Production History (APH) program equal the premium rate at the 65 percent coverage level multiplied by a rate relativity factor that varies by coverage level but not by crop or region. In this paper, we examine the consistency of these constant rate relativity factors with the laws of probability by determining the maximum 65 percent premium rate that is consistent with a well-defined yield distribution. We find that more than 50 percent of U.S. counties have premium rates for corn, soybeans, and wheat that are not consistent with the laws of probability for coverage levels up to 75 percent. For coverage levels up to 85 percent, almost 80 percent of corn counties, 82 percent of soybean counties, and 80 percent of wheat counties have rates that are not consistent. Adding the further restriction that at least 15 percent of probability falls between 85 percent and 100 percent of APH yields implies that 92 percent of corn counties, 90 percent of soybean counties, and 95 percent of wheat counties have APH rates that are not consistent with the laws of probability for coverage levels up to 85 percent. These results imply that crop insurance rates under the APH program in most U.S. production regions at high coverage levels exceed those that could be generated by a well-defined yield distribution.
DO MACROECONOMIC SHOCKS IMPACT THE ECONOMIC EFFICIENCY OF SMALL FARMERS? THE CASE OF WETLAND RICE FARMERS IN INDONESIA
Creators: name: Fabiosa, Jacinto F.
name: Jensen, Helen H.
name: Yan, Dong
name: Fabiosa, Jacinto F.
name: Jensen, Helen H.
name: Yan, Dong
Publisher: name: Unknown
Year: 2004
Subjects: subject: Crop Production/Industries
subject: agriculture
subject: Indonesia
subject: production efficiency
subject: rice

description: This study examines the impact of macroeconomic shocks on the efficiency of small farmers. We estimate single- and multiple-factor efficiency measures for Indonesian rice farmers in years before, during, and after the country's macroeconomic crisis. We find that productive efficiency declined by 7 to 22 percent during the crisis, largely because of a decline in technical efficiency and a relatively large volatility in efficiency (the coefficient of variation was larger by a factor of 1.87). Allocative efficiency, on the other hand, increased slightly and offset part of the decrease in technical efficiency. The magnitude of the impact on efficiency depended on farmers' input adjustments. Factors associated with higher levels of technical and allocative efficiency include larger-size farms and higher education levels for the farm owners. The predicted efficiency measures disaggregated by type (technical and allocative), by specific factor (fertilizer and labor), and by specific location (province and farm level) can be used in designing and targeting interventions to improve the economic efficiency of farms.
Managerial Incentives, Moral Hazard, and Structural Change in Agricultural Cooperatives
Creators: name: Zeuli, Kimberly A.
name: Foltz, Jeremy D.
name: Zeuli, Kimberly A.
name: Foltz, Jeremy D.
Publisher: name: Unknown
Year: 2005
Subjects: Agribusiness

description: The federated business structure exists in many sectors of the economy, but we know little about its comparative advantage. This paper explores theoretically and empirically the current dynamics of the federated cooperative system. Two hypotheses are tested: growth at the local co-op level has made the structure redundant and managerial incentives create disloyalty. We use a unique data set from a survey of local farm supply and grain marketing cooperatives in the Midwest.
Molecular transport calculations with Wannier functions
Creators: name: Thygesen, K. S.
name: Jacobsen, K. W.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We present a scheme for calculating coherent electron transport in atomic-scale contacts. The method combines a formally exact Green's function formalism with a mean-field description of the electronic structure based on the Kohn-Sham scheme of density functional theory. We use an accurate plane-wave electronic structure method to calculate the eigenstates which are subsequently transformed into a set of localized Wannier functions (WFs). The WFs provide a highly efficient basis set which at the same time is well suited for analysis due to the chemical information contained in the WFs. The method is applied to a hydrogen molecule in an infinite Pt wire and a benzene-dithiol (BDT) molecule between Au(111) surfaces. We show that the transmission function of BDT in a wide energy window around the Fermi level can be completely accounted for by only two molecular orbitals.
description: 15 pages, 12 figures, submitted to Chemical Physics
The Effects of the Internet on U.S. Bilateral Trade in Agricultural and Horticultural Commodities
Creators: name: Wheatley, W. Parker
name: Roe, Terry L.
name: Wheatley, W. Parker
name: Roe, Terry L.
Publisher: name: Unknown
Year: 2005
Subjects: subject: Research and Development/Tech Change/Emerging Technologies
subject: Internet
subject: trade
subject: agricultural commodities
subject: technology

description: This paper discusses some of the reasons why the Internet might have a positive effect on the international trade in agricultural and horticultural commodities between the United States and its partners. It provides some simple econometric tests which differentiate the export and import effects of Internet infrastructure and cost. It also shows that the effect may be dependent on product heterogeneity/perishability. Given the growth of the Internet over the past decade, coming to terms and measuring these effects is important to both producers and policymakers in considering the competitive impacts of this new technology.
Bayesian Inferences on Fourier Flexible Functional Form in Agricultural Production
Creators: name: Featherstone, Allen M.
name: Cader, Hanas A.
name: Featherstone, Allen M.
name: Cader, Hanas A.
Publisher: name: Unknown
Year: 2005
Subjects: subject: Research Methods/ Statistical Methods
subject: Cost function
subject: Flexible functional form
subject: Fourier series
subject: Markov Chain Monte Carlo

description: Flexible functional forms are used to examine the characteristics of production technologies. The Fourier functional form is capable of approximating any function globally, with the specified expansion. Unfortunately the exact form of the expansion is not known. The regularity conditions are likely to be violated without the exact form of expansion. In this paper we use a Bayesian approach to impose regularity conditions locally on a Fourier flexible functional from using agricultural production data. Monotonicity, concavity, convexity and elasticities are compared.
Towards Generating Virtual Movement from Textual Instructions A Case Study in Quality Assessment
Creators: name: Sarma, Himangshu
name: Porzel, Robert
name: Smeddinck, Jan
name: Malaka, Rainer
Publisher: name: arXiv
Year: 2020
Subjects: subject: Human-Computer Interaction (cs.HC)
subject: FOS: Computer and information sciences

description: Many application areas ranging from serious games for health to learning by demonstration in robotics, could benefit from large body movement datasets extracted from textual instructions accompanied by images. The interpretation of instructions for the automatic generation of the corresponding motions (e.g. exercises) and the validation of these movements are difficult tasks. In this article we describe a first step towards achieving automated extraction. We have recorded five different exercises in random order with the help of seven amateur performers using a Kinect. During the recording, we found that the same exercise was interpreted differently by each human performer even though they were given identical textual instructions. We performed a quality assessment study based on that data using a crowdsourcing approach and tested the inter-rater agreement for different types of visualizations, where the RGBbased visualization showed the best agreement among the annotators.