cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Two-scale structure of the electron dissipation region during collisionless magnetic reconnection
Creators: name: Shay, M. A.
name: Drake, J. F.
name: Swisdak, M.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: Particle in cell (PIC) simulations of collisionless magnetic reconnection are presented that demonstrate that the electron dissipation region develops a distinct two-scale structure along the outflow direction. The length of the electron current layer is found to decrease with decreasing electron mass, approaching the ion inertial length for a proton-electron plasma. A surprise, however, is that the electrons form a high-velocity outflow jet that remains decoupled from the magnetic field and extends large distances downstream from the x-line. The rate of reconnection remains fast in very large systems, independent of boundary conditions and the mass of electrons.
description: Submitted to Physical Review Letters, 4 pages, 4 figures
Position-Velocity Diagrams for the Maser Emission coming from a Keplerian Ring
Creators: name: Uscanga, Lucero
name: Cantó, Jorge
name: Raga, Alejandro C.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We have studied the maser emission from a thin, planar, gaseous ring in Keplerian rotation around a central mass observed edge-on. The absorption coefficient within the ring is assumed to follow a power law dependence with the distance from the central mass as, k=k0r^{-q}. We have calculated position-velocity diagrams for the most intense maser features, for different values of the exponent q. We have found that, depending on the value of q, these diagrams can be qualitatively different. The most intense maser emission at a given velocity can either come mainly from regions close to the inner or outer edges of the amplifying ring or from the line perpendicular to the line of sight and passing through the central mass (as is commonly assumed). Particularly, when q>1 the position-velocity diagram is qualitatively similar to the one observed for the water maser emission in the nucleus of the galaxy NGC 4258. In the context of this simple model, we conclude that in this object the absorption coefficient depends on the radius of the amplifying ring as a decreasing function, in order to have significant emission coming from the inner edge of the ring.
description: 13 pages, 7 figures, to appear in the 2007 July 20 issue of The Astrophysical Journal
Random-batch list algorithm for short-range molecular dynamics simulations
Creators: name: Liang, Jiuyang
name: Xu, Zhenli
name: Zhao, Yue
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: We propose a fast method for the calculation of short-range interactions in molecular dynamics simulations. The so-called random-batch list method is a stochastic version of the classical neighbor-list method to avoid the construction of a full Verlet list, which introduces two-level neighbor lists for each particle such that the neighboring particles are located in core and shell regions, respectively. Direct interactions are performed in the core region. For the shell zone, we employ a random batch of interacting particles to reduce the number of interaction pairs. The error estimate of the algorithm is provided. We investigate the Lennard-Jones fluid by molecular dynamics simulations, and show that this novel method can significantly accelerate the simulations with a factor of several fold without loss of the accuracy. This method is simple to implement, can be well combined with any linked cell methods to further speed up and scale up the simulation systems, and can be straightforwardly extended to other interactions such as Ewald short-range part, and thus it is promising for large-scale molecular dynamics simulations.
description: 11 pages, 6 figures
From Innovations to Prospects: What Is Hidden Behind Cryptocurrencies?
Creators: name: Jia, Ang
name: Fan, Ming
name: Xu, Xi
name: Cui, Di
name: Wei, Wenying
name: Yang, Zijiang
name: Ye, Kai
name: Liu, Ting
Publisher: name: arXiv
Year: 2021
Subjects: subject: Software Engineering (cs.SE)
subject: FOS: Computer and information sciences

description: The great influence of Bitcoin has promoted the rapid development of blockchain-based digital currencies, especially the altcoins, since 2013. However, most altcoins share similar source codes, resulting in concerns about code innovations. In this paper, an empirical study on existing altcoins is carried out to offer a thorough understanding of various aspects associated with altcoin innovations. Firstly, we construct the dataset of altcoins, including source code repositories, GitHub fork relations, and market capitalizations (cap). Then, we analyze the altcoin innovations from the perspective of source code similarities. The results demonstrate that more than 85% of altcoin repositories present high code similarities. Next, a temporal clustering algorithm is proposed to mine the inheritance relationship among various altcoins. The family pedigrees of altcoin are constructed, in which the altcoin presents similar evolution features as biology, such as power-law in family size, variety in family evolution, etc. Finally, we investigate the correlation between code innovations and market capitalization. Although we fail to predict the price of altcoins based on their code similarities, the results show that altcoins with higher innovations reflect better market prospects.
description: 10 pages
Dynamic Magnetoelastic Boundary Conditions and the Pumping of Phonons
Creators: name: Sato, Takuma
name: Yu, Weichao
name: Streib, Simon
name: Bauer, Gerrit E. W.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We derive boundary conditions at the interfaces of magnetoelastic heterostructures under ferromagnetic resonance for arbitrary magnetization directions and interface shapes. We apply our formalism to magnet$\vert$nonmagnet bilayers and magnetic grains embedded in a nonmagnetic thin film, revealing a nontrivial magnetization angle dependence of acoustic phonon pumping.
description: 17 pages, 5 figures
Unconventional Pairing from Local Orbital Fluctuations in Strongly Correlated A$_3$C$_{60}$
Creators: name: Yue, Changming
name: Hoshino, Shintaro
name: Koga, Akihisa
name: Werner, Philipp
Publisher: name: arXiv
Year: 2021
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: The pairing mechanism in A$_3$C$_{60}$ is investigated by studying the properties of a three-orbital Hubbard model with antiferromagnetic Hund coupling in the normal and superconducting phase. Local orbital fluctuations are shown to be substantially enhanced in the superconducting state, with a fluctuation energy scale that matches the low-energy peak in the spectral weight of the order parameter. Our results demonstrate that local orbital fluctuations provide the pairing glue in strongly correlated fulleride superconductors and support the spin/orbital freezing theory of unconventional superconductivity. They are also consistent with the experimentally observed universal relation between the gap energy and local susceptibility in a broad range of unconventional superconductors.
description: 5+3 pages, 5+7 figures
Fluid flow and heat transfer in continuous casting processes
Creators: name: Matys, Paul
Publisher: name: University of British Columbia
Year: 2010

description: A three-dimensional finite difference code was developed to simulate fluid flow and heat transfer phenomena in continuous casting processes. The mathematical model describes steady state transport phenomena in a three dimensional solution domain that involves: turbulent fluid flow, natural and forced convection, conduction, release of latent heat at the solidus surface, and tracing of unknown location of liquid/solid interface. The governing differential equations are discretized using a finite volume method and a hybrid central, upwind differencing scheme. A fully three-dimensional ADI-like iterative procedure is used to solve the discretized algebraic equations for each dependent variable. The whole system of interlinked equations is solved by the SIMPLE algorithm. The developed computer code was used for parametric studies of continuous casting of aluminum. The results were compared against available experimental data. This numerical simulation enhances understanding of the fluid flow and heat transfer phenomena in continuous casting processes and can be used as a tool to optimize technologies for continuous casting of metals.
title: Three essays in labour economics
Creators: name: Mansoor, Nayha
Publisher: name: University of St Andrews
Year: 2020

description: This thesis extends the existing literature on the response of labour markets to different types of economic shocks. First, we examine the effects of sector-specific fluctuations in job separation and job finding rates on the overall unemployment, sectoral allocation of labour and wages by solving a two-sector search and matching model with heterogeneous workers. The simulated results show how sector-specific shocks spill over the rest of the economy, causing workers to relocate between sectors in search of jobs. Inter-sectoral reallocation depends on the distribution of worker productivity in the affected sector. When an adverse shock hits a sector that attracts workers with relatively low productivity, the most productive among displaced workers move to compete for jobs in the sector with higher productivity. This offsets some of the increase in unemployment, subject to the ability of unaffected sector to employ additional workers. Next, we conduct meta-analysis to explain discrepancies between estimated effects of immigration shocks on wages in the literature. The results show that wage impact of immigration tends to be small in magnitude and negative significant. Labour market conditions at the period of study play a significant role in explaining the differences in measured impact. The estimates vary across countries and are related to the choice of modelling approach and estimators. Finally, we use EU-LFS dataset to analyse unemployment and labour market flows in Europe between 2006 and 2016. We identify the relative impact of shocks to job finding and separation rates on unemployment and investigate the role of socio-demographics, urbanisation and immigration status in shaping worker flow patterns in Europe. We find that over the studied period job losses accounted for three quarters of the rise in unemployment. The analysis of socio-demographic characteristics of the unemployed shows that young and less educated workers contributed the most to employment losses. Recent and intermediate immigrants in cities contributed to employment losses.
Digitális logisztikai megoldások értékelése a magyar és lengyel fiatalok körében
Creators: name: Kurucz, Attila
name: Dernóczy-Polyák, Adrienn
name: Osieczko, Kornelia
Publisher: name: BI-KA LOGISZTIKA Kft.
Year: 2020

description: Logisztikai trendek és legjobb gyakorlatok (Nyomtatott ISSN: 2416-0555, Online ISSN: 2560-0362), 2020. december, VI. évfolyam, 2. szám
Optimal Commodity Taxation and Income Distribution
Creators: name: Benassi, Corrado
name: Randon, Emanuela
Publisher: name: Alma Mater Studiorum - Università di Bologna
Year: 2015
Subjects: SECS-P/01 Economia politica

description: We consider the interplay between income distribution and optimal commodity taxation, linking equity issues to optimal taxes through the effect of income distribution on market demand and its price elasticity.
We find conditions to conciliate the equity and efficiency tradeoff and to assess the impact of inequality changes on the optimal taxation of necessity and luxury goods. We show that the regressivity or progressivity of the tax system is determined by the distribution of luxuries and necessities in the economy. If the tax system is regressive (progressive), a decrease (increase) of income inequality leads to an average decrease of the optimal tax rates, achieving welfare gains for society. Our analysis provides a framework to investigate the linkages between direct and indirect taxation.
Country-of-Origin Labeling for Processed Foods
Creators: name: Su, Yuezhen <1962>
Publisher: name: Alma Mater Studiorum - Università di Bologna
Year: 2014
Subjects: AGR/01 Economia ed estimo rurale

description: The country-of-origin is the “nationality” of a food when it goes through customs in a foreign country, and is a “brand” when the food is for sale in a foreign market. My research on country-of-origin labeling (COOL) started from a case study on the extra virgin olive oil exported from Italy to China; the result shows that asymmetric and imperfect origin information may lead to market inefficiency, even market failure in emerging countries. Then, I used the Delphi method to conduct qualitative and systematic research on COOL; the panel of experts in food labeling and food policy was composed of 19 members in 13 countries; the most important consensus is that multiple countries of origin marking can provide accurate information about the origin of a food produced by two or more countries, avoiding misinformation for consumers. Moreover, I enhanced the research on COOL by analyzing the rules of origin and drafting a guideline for the standardization of origin marking. Finally, from the perspective of information economics I estimated the potential effect of the multiple countries of origin labeling on the business models of international trade, and analyzed the regulatory options for mandatory or voluntary COOL of main ingredients. This research provides valuable insights for the formulation of COOL policy.
Predicting hyperlinks via hypernetwork loop structure
Creators: name: Pan, Liming
name: Shang, Hui-Juan
name: Li, Peiyan
name: Dai, Haixing
name: Wang, Wei
name: Tian, Lixin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Social and Information Networks (cs.SI)
subject: Physics and Society (physics.soc-ph)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: While links in simple networks describe pairwise interactions between nodes, it is necessary to incorporate hypernetworks for modeling complex systems with arbitrary-sized interactions. In this study, we focus on the hyperlink prediction problem in hypernetworks, for which the current state-of-art methods are latent-feature-based. A practical algorithm via topological features, which can provide understandings of the organizational principles of hypernetworks, is still lacking. For simple networks, local clustering or loop reflects the correlations among nodes; therefore, loop-based link prediction algorithms have achieved accurate performance. Extending the idea to hyperlink prediction faces several challenges. For instance, what is an effective way of defining loops for prediction is not clear yet; besides, directly comparing topological statistics of variable-sized hyperlinks could introduce biases in hyperlink cardinality. In this study, we address the issues and propose a loop-based hyperlink prediction approach. First, we discuss and define the loops in hypernetworks; then, we transfer the loop-features into a hyperlink prediction algorithm via a simple modified logistic regression. Numerical experiments on multiple real-world datasets demonstrate superior performance compared to the state-of-the-art methods.
Dissipation and fluctuations in elongated bosonic Josephson junctions
Creators: name: Binanti, F.
name: Furutani, K.
name: Salasnich, L.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: We investigate the dynamics of bosonic atoms in elongated Josephson junctions. We find that these systems are characterized by an intrinsic coupling between the Josephson mode of macroscopic quantum tunneling and the sound modes. This coupling of Josephson and sound modes gives rise to a damped and stochastic Langevin dynamics for the Josephson degree of freedom. From a microscopic Lagrangian, we deduce and investigate the damping coefficient and the stochastic noise, which includes thermal and quantum fluctuations. Finally, we study the time evolution of relative-phase and population-imbalance fluctuations of the Josephson mode and their oscillating thermalization to equilibrium.
description: 9 pages, 5 figures, improved version with more detailed explanations, to be published in Phys. Rev. A
Link representation of the entanglement entropies for all bipartitions
Creators: name: Roy, Sudipto Singha
name: Santalla, Silvia N.
name: Sierra, Germán
name: Rodríguez-Laguna, Javier
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We have recently shown that the entanglement entropy of any bipartition of a quantum state can be approximated as the sum of certain link strengths connecting internal and external sites. The representation is useful to unveil the geometry associated with the entanglement structure of a quantum many-body state which may occasionally differ from the one suggested by the Hamiltonian of the system. Yet, the obtention of these entanglement links is a complex mathematical problem. In this work, we address this issue and propose several approximation techniques for matrix product states, free fermionic states, or in cases in which contiguous blocks are specially relevant. Along with this, we discuss the accuracy of the approximation for different types of states and partitions. Finally, we employ the link representation to discuss two different physical systems: the spin-1/2 long-range XXZ chain and the spin-1 bilinear biquadratic chain.
description: 26 pages, 15 figures, 3 tables
Logisztikai folyamatok lean fejlesztése VSM és monozukuri módszerrel
Creators: name: Vajna, István
name: Tangl, Anita
Publisher: name: BI-KA LOGISZTIKA Kft.
Year: 2020

description: Logisztikai trendek és legjobb gyakorlatok (Nyomtatott ISSN: 2416-0555, Online ISSN: 2560-0362), 2020. december, VI. évfolyam, 2. szám
Structure of $^{46,47}$Ca from the $β^-$ decay of $^{46,47}$K in the framework of nuclear shell model
Creators: name: Choudhary, Priyanka
name: Kumar, Anil
name: Srivastava, Praveen C.
name: Suzuki, Toshio
Publisher: name: arXiv
Year: 2021
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: In the present work, we report a comprehensive theoretical study of the $\log ft$ values for the allowed and forbidden $β^-$ decay transitions of $^{46}$K and $^{47}$K corresponding to recently available experimental data from the GRIFFIN spectrometer at TRIUMF-ISAC [Phys. Rev. C {\bf 100}, 054327 (2019); Phys. Rev. C {\bf 102}, 054314 (2020)]. We perform the nuclear shell-model calculation in $sdpf$-valence space, with the SDPF-MU interaction, to calculate low-lying energy spectra of $^{46,47}$K and $^{46,47}$Ca. For further investigation, we also calculate spectroscopic properties of $^{46,47}$K, $^{46,47}$Ca and compare the results with the experimental data. We suggest spin-parity of several levels, which were previously tentative, in both the calcium isotopes. Based on the energy and $\log ft$ values, we conclude that the state at 3.984 MeV in $^{46}$Ca could be either $3^{-}$ or $2^{+}$ and a state at 4.432 MeV might be $3^{-}$. The spin-parity of the states at 2.875, 3.951 and 4.453 MeV are predicted to be $1/2^-$, $3/2^-$ and $1/2^-$ or $1/2^+$, respectively, in $^{47}$Ca. We also give the confirmation to spin-parity of 2.850, 3.889 and 4.606 MeV states for $^{47}$Ca. Our results of level schemes of $^{46,47}$K are in a reasonable agreement with the experimental data, while the agreement of calculated $\log ft$ values for the $β^-$ decay with the experimental data is limited.
description: 11 pages, 4 figures, 5 tables
Information Synergy in the Anticipatory Dynamics of a Retina
Creators: name: Lin, Qi-Rong
name: Chou, Po-Yu
name: Chan, C. K.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Neurons and Cognition (q-bio.NC)
subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: Biological Physics (physics.bio-ph)
subject: FOS: Biological sciences
subject: FOS: Physical sciences

description: Visual perceptions often come with illusions whose physical origin are not well understood yet. The encoding of stochastic light intensity $x(t)$ into spikes with firing rate $r(t)$ at time $t$ is investigated in an experiment with retinas from bullfrogs to understand the mechanism of anticipation. Partial information decomposition of the mutual information between $r$ and the combined state $\{x,\dot x\}$ is found to be consistent with the encoding form: $r(t) \sim (1-λ)x(t) + λ\dot x(t) τ_0$ with $λ$ being a system dependent parameter and $τ_0$ a constant. This form of $r(t)$ indicates that a retina is capable of anticipation based on the synergistic information generation between $x$ and $\dot x$. Our results suggest that illusions such as the anticipation studied here during retinal perception can originate from the recombination of information extracted in the retinal network.
Better Accessibility Research for the Future
Creators: name: Harper, Simon
Publisher: name: Zenodo
Year: 2019
Subjects: keynote
accessibility
advice
impact
reproducibility
Health Induced Impairments and Disabilities
HIIDs

description: Welcome to my insecurities, and the lonely questions I ask myself at 03:00 in the morning. I'll present five 'Notes to My Past Self' which outline the things I should have considered - and am now considering - which would have made my accessibility work better…
Suppression of the radiation squeezing in interacting quantum Hall edge channels
Creators: name: Rebora, G.
name: Ferraro, D.
name: Sassetti, M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We study the quantum fluctuations of the two quadratures of the emitted electromagnetic radiation generated by a quantum Hall device in a quantum point contact geometry. In particular, we focus our attention on the role played by the unavoidable electron-electron interactions between the two edge channels at filling factor two. We investigate quantum features of the emitted microwave radiation, such as squeezing, by studying the current fluctuations at finite frequency, accessible through a two-filters set-up placed just after the quantum point contact. We compare two different drives, respectively a cosine and a train of Lorentzian pulses, used for the injection of the excitations into the system. In both cases quantum features are reduced due to the interactions, however the Lorentzian drive is still characterized by a robust squeezing effect which can have important application on quantum information.
description: 21 pages, 8 figures
VLT observations of the Central Compact Object in the Vela Jr. supernova remnant
Creators: name: Mignani, R. P.
name: De Luca, A.
name: Zaggia, S.
name: Sester, D.
name: Pellizzoni, A.
name: Mereghetti, S.
name: Caraveo, P. A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: X-ray observations have unveiled the existence of enigmatic point-like sources at the center of young (a few kyrs) supernova remnants. These sources, known as Central Compact Objects (CCOs), are thought to be neutron stars produced by the supernova explosion, although their X-ray phenomenology makes them markedly different from all the other young neutron stars discovered so far.The aim of this work is to search for the optical/IR counterpart of the Vela Junior CCO and to understand the nature of the associated Halpha nebula discovered by Pellizzoni et al. (2002).}{We have used deep optical (R band) and IR (J,H,Ks bands) observations recently performed by our group with the ESO VLT to obtain the first deep, high resolution images of the field with the goal of resolving the nebula structure and pinpointing a point-like source possibly associated with the neutron star.Our R-band image shows that both the nebula's flux and its structure are very similar to the Halpha ones, suggesting that the nebula spectrum is dominated by pure Halpha line emission. However, the nebula is not detected in our IR observations, whick makes it impossible to to constrain its spectrum. A faint point-like object (J>22.6, H~21.6, Ks ~ 21.4) compatible with the neutron star's Chandra X-ray position is detected in our IR images (H and Ks) but not in the optical one (R > 25.6), where it is buried by the nebula background. The nebula is most likely a bow-shock produced by the neutron star motion through the ISM or, alternatively, a photo-ionization nebula powered by UV radiation from a hot neutron star.
description: 8 pages, 4 figures, A&Aaccepted
States of Low Energy in bouncing inflationary scenarios in Loop Quantum Cosmology
Creators: name: Martín-Benito, Mercedes
name: Neves, Rita B.
name: Olmedo, Javier
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In generic Friedmann-Lemaître-Robertson-Walker spacetimes, States of Low Energy (SLEs) are defined to minimize the regularized energy density smeared along the time-like curve of an isotropic observer, which is specified via a smearing function. For every smearing function, SLEs are unique (up to a phase) and are shown to be exact Hadamard states. In this work, we investigate the viability of SLEs as the vacuum for cosmological perturbations in hybrid Loop Quantum Cosmology, motivated by the fact that SLEs have been shown to provide suitable vacua in models where a period of kinetic dominance precedes inflation. We find that there are two classes of smearing functions that can be seen as natural choices within this context, for which the corresponding SLEs and the resulting power spectra at the end of inflation are quite insensitive to the exact shape and support of the smearing function. Furthermore, a preliminary analysis of the tensor-to-scalar ratio and of the spectral index indicates as good an agreement with observations as that of standard cosmology.
description: 10 pages, 3 figures, v2: matches published version
Isothermal scale model study of the gas flow field in a hog fuel boiler furnace
Creators: name: Perchanok, Mathias Samson
Publisher: name: University of British Columbia
Year: 2010

description: Good combustion is required to maximize steam generation and avoid emissions in the wood waste fired boilers found frequently in the pulp and paper industry. The combustion process is assisted if velocities above the grate are minimized, if gases in the combustion zone are mixed intimately, and if gaseous combustion is concentrated above the grate. A 1/15 scale replica of a power boiler was constructed for isothermal flow modelling of the flow field above the grate, the overfire air jets and the furnace up to the generating banks. The flow was made visible with smoke, and velocities were measured with a pulsed wire anemometer. It was found that a very non uniform velocity profile occurred above the fuel grate because the under grate plenum did not adequately diffuse the under grate air flow. Also, non perforated areas of the fuel grate near the furnace walls caused recirculation zones to occur above the grate near the front wall. The recirculation zones of the overfire air jets caused high velocities to occur above the grate as well. A large space between the front wall and the front overfire air nozzles on the side walls, caused vertical stratification of the flow, in which gases rising from the grate, near the front wall did not mix with the overfire air. At part load, reduced velocity in the overfire air jets caused vertical stratification of the flow as well, in which mixture of gases rising from the grate and overfire air occurred well above the fuel grate. At high nozzle velocities, gases were well mixed, throughout the cross section, large recirculations occurred and mixing was concentrated near the fuel grate. Established models for jets for free turbulent jets do not accurately represent opposing banks of jets. Centerline velocity is overpredicted by a factor of two or more, and deflection of the jet are greatly underpredicted by the models. Throw and penetration, calculated with the models do not give reasonable predictions, indicating the need for more sophisticated models. At high overfire air flow rates, oscillation of the overfire air jets was observed, with a period in the order of one second.
Notice Regarding Videoconference Services (Data Protection Officer, Berlin)
Creators: name: Hamacher, Alaric
Publisher: name: Zenodo
Year: 2020
Subjects: Videoconference
Privacy
Security
Data Protection

description: The Data Protection Officer of Berlin, Germany published a an evaluation of videoconferencing services on July 7 2020. The Paper analyzes multiple video conferencing services and ranks them according to a traffic light system. The ranking system aims at helping responsible decision makers in companies and institutions to choses services, that are complying with the required levels of data protection in Germany. The author republishes this document available online at the URL: https://www.datenschutz-berlin.de/fileadmin/user_upload/pdf/orientierungshilfen/2020-BlnBDI-Hinweise_Berliner_Verantwortliche_zu_Anbietern_Videokonferenz-Dienste.pdf The original document was created by the Berliner Beauftragte für Datenschutz und Informationsfreiheit and made available on July 7 2020.
description: The original document was created by the Berliner Beauftragte für Datenschutz und Informationsfreiheit and made available on July 7 2020.
Coupling of whispering-gallery modes in size-mismatched microdisk photonic molecules
Creators: name: Boriskina, Svetlana V.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Mechanisms of whispering-gallery (WG) modes coupling in microdisk photonic molecules (PMs) with slight and significant size mismatch are numerically investigated. The results reveal two different scenarios of modes interaction depending on the degree of this mismatch and offer new insight into how PM parameters can be tuned to control and modify WG-modes wavelengths and Q-factors. From a practical point of view, these findings offer a way to fabricate PM microlaser structures that exhibit low thresholds and directional emission, and at the same time are more tolerant to fabrication errors than previously explored coupled-cavity structures composed of identical microresonators.
description: 3 pages with 5 figures (to appear in Opt. Lett. 2007)
Scaling Symmetries of Scatterers of Classical Zero-Point Radiation
Creators: name: Boyer, Timothy H.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Classical Physics (physics.class-ph)
subject: General Physics (physics.gen-ph)
subject: FOS: Physical sciences

description: Classical radiation equilibrium (the blackbody problem) is investigated by the use of an analogy. Scaling symmetries are noted for systems of classical charged particles moving in circular orbits in central potentials V(r)=-k/r^n when the particles are held in uniform circular motion against radiative collapse by a circularly polarized incident plane wave. Only in the case of a Coulomb potential n=1 with fixed charge e is there a unique scale-invariant spectrum of radiation versus frequency (analogous to zero-point radiation) obtained from the stable scattering arrangement. These results suggest that non-electromagnetic potentials are not appropriate for discussions of classical radiation equilibrium.
description: 13 pages
Phenomenological implications of modified loop cosmologies: an overview
Creators: name: Li, Bao-Fei
name: Singh, Parampreet
name: Wang, Anzhong
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In this paper, we first provide a brief review of the effective dynamics of two recently well-studied models of modified loop quantum cosmologies (mLQCs), which arise from different regularizations of the Hamiltonian constraint and show the robustness of a generic resolution of the big bang singularity, replaced by a quantum bounce due to non-perturbative Planck scale effects. As in loop quantum cosmology (LQC), in these modified models the slow-roll inflation happens generically. We consider the cosmological perturbations following the dressed and hybrid approaches and clarify some subtle issues regarding the ambiguity of the extension of the effective potential of the scalar perturbations across the quantum bounce, and the choice of initial conditions. Both of the modified regularizations yield primordial power spectra that are consistent with current observations for the Starobinsky potential within the framework of either the dressed or the hybrid approach. But differences in primordial power spectra are identified among the mLQCs and LQC. In addition, for mLQC-I, striking differences arise between the dressed and hybrid approaches in the infrared and oscillatory regimes. While the differences between the two modified models can be attributed to differences in the Planck scale physics, the permissible choices of the initial conditions and the differences between the two perturbation approaches have been reported for the first time. All these differences, due to either the different regularizations or the different perturbation approaches in principle can be observed in terms of non-Gaussianities.
description: revtex4, 11 figures, and no tables. Contribution to the Special Issue "Loop Quantum Cosmology" in Frontiers in Astronomy and Space Sciences, edited by B. Elizaga-Navascu\'es, G. Mena-Marug\'an, and F. Vidotto
Spin solid phases of spin 1 and spin 3/2 antiferromagnets on a cubic lattice
Creators: name: Gregor, Karol
name: Motrunich, Olexei I.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We study spin S=1 and S=3/2 Heisenberg antiferromagnets on a cubic lattice focusing on spin solid states. Using Schwinger boson formulation for spins, we start in a U(1) spin liquid phase proximate to Neel phase and explore possible confining paramagnetic phases as we transition away from the spin liquid by the process of monopole condensation. Electromagnetic duality is used to rewrite the theory in terms of monopoles. For spin 1 we find several candidate phases of which the most natural one is a phase with spins organized into parallel Haldane chains. For spin 3/2 we find that the most natural phase has spins organized into parallel ladders. As a by-product, we also write a Landau theory of the ordering in two special classical frustrated XY models on the cubic lattice, one of which is the fully frustrated XY model. In a particular limit our approach maps to a dimer model with 2S dimers coming out of every site, and we find the same spin solid phases in this regime as well.
description: 15 pages, 8 figures
Additional file 3 of Depth-dependent variability of biological nitrogen fixation and diazotrophic communities in mangrove sediments
Creators: name: Luo, Zhiwen
name: Zhong, Qiuping
name: Han, Xingguo
name: Hu, Ruiwen
name: Liu, Xingyu
name: Xu, Wenjun
name: Wu, Yongjie
name: Huang, Weiming
name: Zhou, Zhengyuan
name: Zhuang, Wei
name: Yan, Qingyun
name: He, Zhili
name: Wang, Cheng
Publisher: name: figshare
Year: 2021
Subjects: subject: Microbiology
subject: FOS: Biological sciences
subject: Environmental Sciences not elsewhere classified
subject: Ecology
subject: Biological Sciences not elsewhere classified

description: Additional file 2: Table S1. A summary of reads information and microbial classification at different taxonomical levels. Table S2. Pearson’s correlations between the abundance of diazotrophic genera and the nitrogen fixation rate (NFR). Table S3. Relative abundances of diazotrophic communities at the genus level. Table S4. Mantel test for the correlations between diazotrophic community structure and sediment properties. Fig. S1. The location of the sampling habitats at the Qi’ao Island, Guangdong Province, China. Fig. S2. Relationships between the depth of mangrove sediments and the NFR (a), water content (b), salinity (c), Shannon index (d) and Chao1 index (e). NFR was represented as acetylene reduction (nmol g-1 h-1) in this research. Black lines and grey shaded areas represent linear regressions and 95% confidence intervals, respectively. R2 was obtained by linear regression analysis and p was obtained by Pearson’s correlation analysis. Fig. S3. The in-depth profile of physicochemical properties. The concentration of NH4+ (a), NO2- (b), NO3- (c), pH (d), water content (e), salinity (f), total Fe (g), available Fe (h) and Fe3+ (i) across 10 depths of mangrove sediments. Boxplots depict the 25-75% quantile range of the selected measurements, with the centerline depicting the median (50% quantile). Whiskers show the minimum and maximum values. Fig. S4. Bray-Curtis distance-based hierarchical clustering of diazotrophic communities across 10 depths of mangrove sediments. The color gradient represents sediment depth.
Scouting the Path to a Million-Client Server
Creators: name: Zhao, Yimeng
name: Saeed, Ahmed
name: Ammar, Mostafa
name: Zegura, Ellen
Publisher: name: arXiv
Year: 2021
Subjects: subject: Networking and Internet Architecture (cs.NI)
subject: Performance (cs.PF)
subject: FOS: Computer and information sciences

description: To keep up with demand, servers will scale up to handle hundreds of thousands of clients simultaneously. Much of the focus of the community has been on scaling servers in terms of aggregate traffic intensity (packets transmitted per second). However, bottlenecks caused by the increasing number of concurrent clients, resulting in a large number of concurrent flows, have received little attention. In this work, we focus on identifying such bottlenecks. In particular, we define two broad categories of problems; namely, admitting more packets into the network stack than can be handled efficiently, and increasing per-packet overhead within the stack. We show that these problems contribute to high CPU usage and network performance degradation in terms of aggregate throughput and RTT. Our measurement and analysis are performed in the context of the Linux networking stack, the the most widely used publicly available networking stack. Further, we discuss the relevance of our findings to other network stacks. The goal of our work is to highlight considerations required in the design of future networking stacks to enable efficient handling of large numbers of clients and flows.
Braided quantum field theories and their symmetries
Creators: name: Sasai, Yuya
name: Sasakura, Naoki
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Braided quantum field theories proposed by Oeckl can provide a framework for defining quantum field theories having Hopf algebra symmetries. In quantum field theories, symmetries lead to non-perturbative relations among correlation functions. We discuss Hopf algebra symmetries and such relations in braided quantum field theories. We give the four algebraic conditions between Hopf algebra symmetries and braided quantum field theories, which are required for the relations to hold. As concrete examples, we apply our discussions to the Poincare symmetries of two examples of noncommutative field theories. One is the effective quantum field theory of three-dimensional quantum gravity coupled with spinless particles given by Freidel and Livine, and the other is noncommutative field theory on Moyal plane. We also comment on quantum field theory on kappa-Minkowski spacetime.
description: 36 pages, 18 figures, a comment added and typos corrected
Aperiodic bandgap structures for enhanced quantum two-photon sources
Creators: name: Negro, Luca Dal
name: Chen, Yuyao
name: Gorsky, Sean
name: Sgrignuoli, Fabrizio
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: In this paper we propose a novel approach to enhance the efficiency of the two-photon spontaneous emission process that is driven by the multifractal optical mode density of photonic structures based on the aperiodic distributions of Eisenstein and Gaussian primes. In particular, using the accurate Mie-Lorenz multipolar theory in combination with multifractal detrended fluctuation analysis, we compute the local density of states of periodic and aperiodic systems and demonstrate the formation of complete bandgaps with distinctive fractal scaling behavior for scattering arrays of dielectric nanocylinders. Moreover, we systematically study the Purcell enhancement and the most localized optical mode resonances in these novel aperiodic photonic systems and compute their two-photon spontaneous emission rates based on the general Green's tensor approach. Our results demonstrate that the excitation of the highly-resonant critical states of Eisenstein and Gaussian photonic arrays across broadband multifractal spectra gives rise to significantly enhanced emission rates compared to what is possible at the band-edges of periodic structures with comparable size. Besides defining a novel approach for enhanced quantum two-photon sources on the chip, the engineering of aperiodic bandgap structures with multifractal mode density may provide access to novel electromagnetic resonant phenomena in a multiscale-invariant vacuum for quantum nanophotonics applications.
description: 14 pages, 9 Figures
Zarismus, Bourgeoisie und Arbeiterklasse in Rußland Anfang des 20. Jahrhunderts (politische Aspekte)
Creators: name: Potolov, Sergej I.
Publisher: name: Moving the Social
Year: 2014

description: This is the contribution "Zarismus, Bourgeoisie und Arbeiterklasse in Rußland Anfang des 20. Jahrhunderts (politische Aspekte)" of MTS 16 (1995).
description: Moving the Social, Vol 16 (1995): Forschungen zur Arbeiterschaft und Arbeiterbewegung in Rußland
Sobolev regularity of solutions of the cohomological equation
Creators: name: Forni, Giovanni
Publisher: name: arXiv
Year: 2007
Subjects: subject: Dynamical Systems (math.DS)
subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 37A20, 37C10, 37C15

description: We refine the theory of the cohomological equation for translation flows on higher genus surfaces with the goal of proving optimal results on the Sobolev regularity of solutions and of distributional obstructions. For typical translation surfaces our results are sharp and we find the expected relation between the regularity of the distributional obstructions and the Lyapunov exponents of the Kontsevich-Zorich renormalization cocycle. As a consequence we exactly determine the dimension of the space of obstructions in each Sobolev regularity class in terms of the Kontsevich-Zorich exponents. For a fixed arbitrary translation surface and a typical direction, our results are probably not optimal but are the best which can be achieved with the available harmonic analysis techniques we have introduced in an earlier paper.
description: 119 pages
Die Selbstorganisation von Arbeitskollektiven und die Mentalität der Arbeiter in Petersburg Anfang des 20. Jahrhunderts
Creators: name: Michajlov, Nikolaj V.
Publisher: name: Moving the Social
Year: 2014

description: This is the contribution "Die Selbstorganisation von Arbeitskollektiven und die Mentalität der Arbeiter in Petersburg Anfang des 20. Jahrhunderts" of MTS 16 (1995).
description: Moving the Social, Vol 16 (1995): Forschungen zur Arbeiterschaft und Arbeiterbewegung in Rußland
A major asymmetric ice trap in a planet-forming disk: II. prominent SO and SO2 pointing to C/O < 1
Creators: name: Booth, A. S.
name: van der Marel, N.
name: Leemker, M.
name: van Dishoeck, E. F.
name: Ohashi, S.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Gas-phase sulphur bearing volatiles appear to be severely depleted in protoplanetary disks. The detection of CS and non-detections of SO and SO2 in many disks have shown that the gas in the warm molecular layer, where giant planets accrete their atmospheres, has a high C/O ratio. In this letter, we report the detection of SO and SO2 in the Oph-IRS 48 disk using ALMA. This is the first case of prominent SO2 emission detected from a protoplanetary disk. The molecular emissions of both molecules is spatially correlated with the asymmetric dust trap. We propose that this is due to the sublimation of ices at the edge of the dust cavity and that the bulk of the ice reservoir is coincident with the millimetre dust grains. Depending on the partition of elemental sulphur between refractory and volatile materials the observed molecules can account for 15-100% of the total sulphur budget in the disk. In strong contrast to previous results, we constrain the C/O ratio from the CS/SO ratio to be < 1 and potentially solar. This has important implications for the elemental composition of planets forming within the cavities of warm transition disks.
description: Accepted to A&A Letters 7th June 2021
Cost-effectiveness analysis of levonorgestrel-releasing intrauterine system (LNG-IUS) 52 mg versus other long-acting reversible contraceptives for contraception in Spain
Creators: name: Conde, José C. Quílez
name: Ribes, Inmaculada Parra
name: Perelló-Capo, Josep
name: Abascal, Paloma Lobo
name: García, Ignacio Cristóbal
name: García, Mercedes Andeyro
name: Alés, José Gutiérrez
name: Conde, Mercedes Herrero
name: Tarruella, Joan Rius
name: Lafuente, Belén Espinós
Publisher: name: Taylor & Francis
Year: 2024
Subjects: Pharmacology
Environmental Sciences not elsewhere classified
Biological Sciences not elsewhere classified
Science Policy

description: Condoms and combined oral contraceptive pills are widely used in Spain with high failure rates. Long-Acting Reversible Contraceptive (LARC) methods offer better efficacy and adherence and reduce unintended pregnancies (UP) compared with short-acting reversible contraceptive (SARC) methods. To assess the cost-effectiveness of LNG-IUS 52 mg (Mirena®) versus other LARC for contraception in Spain. A Markov model with annual cycles and an eight-year time horizon was developed from the Spanish national healthcare system (NHS) perspective, considering costs for contraceptive method acquisition, health care resources (HCR) and UP. Effectiveness was based on failure and discontinuation rates. Sensitivity analyses were performed to test the model’s robustness. LNG-IUS 52 mg (Mirena®) resulted in lower costs and fewer UP versus LNG-IUS 13.5 mg (Jaydess®), Implant (Implanon®) and Copper IUD. LNG-IUS 52 mg (Levosert®) prevented the same UP events at a higher cost. LNG-IUS 19.5 mg (Kyleena®) was the most effective option, due to a lower discontinuation rate. LNG-IUS 52 mg (Mirena®) is the least costly LARC, driven by lower acquisition costs and reduced HCR utilisation. Increasing LNG-IUS 52 mg (Mirena®) uptake in contraception could generate further cost savings for the Spanish NHS and reduce economic burden of UP. Levonorgestrel-releasing intrauterine system (LNG-IUS; Mirena®) is an effective and cost-saving long-acting reversible contraceptive (LARC) method compared with other similar methods in Spain over an eight-year time horizon, and Kyleena® was the most effective option.