cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Effect of a small disruption of the Ca site on the geometrically frustrated magnetic behavior of Ca3CoRhO6
Creators: name: Mohapatra, Niharika
name: Sampathkumaran, E. V.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The compound, Ca3CoRhO6, containing magnetic Co-Rh chains intervened by Ca ions, has been known to be one of the few exhibiting partially disordered antiferromagnetic structure (PDA) due to geometrical frustration. Here, we report the influence of partial replacement of Ca by Y on the magnetic anomalies by investigating the solid solution, Ca(3-x)Y(x)CoRhO6 by bulk measurements. There are profound changes in the magnetic behavior, the most notable one being that the features attributable to spin-chain magnetism and PDA structure get suppressed dramatically by a small replacement of Ca by Y (x= 0.15), despite the fact that the magnetic chain is not disrupted. This finding suggests that this compound is on the verge of PDA-structural-instability.
description: 10 pages including 5 figures
Self-Spin-Controlled Rotation of Spatial States of a Dirac Electron in a Cylindrical Potential via Spin-Orbit Interaction
Creators: name: Leary, C. C.
name: Reeb, D.
name: Raymer, M. G.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Solution of the Dirac equation predicts that when an electron with non-zero orbital angular momentum propagates in a cylindrically symmetric potential, its spin and orbital degrees of freedom interact, causing the electron's phase velocity to depend on whether its spin and orbital angular momenta vectors are oriented parallel or anti-parallel with respect to each other. This spin-orbit splitting of the electronic dispersion curves can result in a rotation of the electron's spatial state in a manner controlled by the electron's own spin z-component value. These effects persist at non-relativistic velocities. To clarify the physical origin of this effect, we compare solutions of the Dirac equation to perturbative predictions of the Schrodinger-Pauli equation with a spin-orbit term, using the standard Foldy-Wouthuysen Hamiltonian. This clearly shows that the origin of the effect is the familiar relativistic spin-orbit interaction.
description: 14 pages, 5 figures, 2 appendices, final version
Computer algebra in Julia
Creators: name: Kulyabov, Dmitry S.
name: Korolkova, Anna V.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Symbolic Computation (cs.SC)
subject: FOS: Computer and information sciences

description: Recently, the place of the main programming language for scientific and engineering computations has been little by little taken by Julia. Some users want to work completely within the Julia framework as they work within the Python framework. There are libraries for Julia that cover the majority of scientific and engineering computations demands. The aim of this paper is to combine the usage of the Julia framework for numerical computations and for symbolic computations in mathematical modeling problems. The main functional domains determining various variants of the application of computer algebra systems are described. In each of these domains, generic representatives of computer algebra systems in Julia are distinguished. The conclusion is that it is possible (and even convenient) to use computer algebra systems within the Julia framework.
description: in English; in Russian
Kinetic instability in inductively oscillatory plasma equilibrium
Creators: name: Cruz, Fábio
name: Grismayer, Thomas
name: Silva, Luis O.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: A uniform in space, oscillatory in time plasma equilibrium sustained by a time-dependent current density is analytically and numerically studied resorting to particle-in-cell simulations. The dispersion relation is derived from the Vlasov equation for oscillating equilibrium distribution functions, and used to demonstrate that the plasma has an infinite number of unstable kinetic modes. This instability represents a new kinetic mechanism for the decay of the initial mode of infinite wavelength (or equivalently null wavenumber), for which no classical wave breaking or Landau damping exists. The relativistic generalization of the instability is discussed. In this regime, the growth rate of the fastest growing unstable modes scales with $γ_T^{-1/2}$, where $γ_T$ is the largest Lorentz factor of the plasma distribution. This result hints that this instability is not as severely suppressed for large Lorentz factor flows as purely streaming instabilities. The relevance of this instability in inductive electric field oscillations driven in pulsar magnetospheres is discussed.
Predicting the Yields of Photometric Surveys for Transiting Extrasolar Planets
Creators: name: Beatty, Thomas G.
name: Gaudi, B. Scott
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We develop a method for predicting the yield of transiting planets from a photometric survey given the parameters of the survey (nights observed, bandpass, exposure time, telescope aperture, locations of the target fields, observational conditions, and detector characteristics), as well as the underlying planet properties (frequency, period and radius distributions). Using our updated understanding of transit surveys provided by the experiences of the survey teams, we account for those factors that have proven to have the greatest effect on the survey yields. Specifically, we include the effects of the surveys' window functions, adopt revised estimates of the giant planet frequency, account for the number and distribution of main-sequence stars in the survey fields, and include the effects of Galactic structure and interstellar extinction. We approximate the detectability of a planetary transit using a signal-to-noise ratio (S/N) formulation. We argue that our choice of detection criterion is the most uncertain input to our predictions, and has the largest effect on the resulting planet yield. Thus drawing robust inferences about the frequency of planets from transit surveys will require that the survey teams impose and report objective, systematic, and quantifiable detection criteria. Nevertheless, with reasonable choices for the minimum S/N, we calculate yields that are generally lower, more accurate, and more realistic than previous predictions. As examples, we apply our method to the Trans-Atlantic Exoplanet Survey, the XO survey, and the {\it Kepler} mission. We discuss red noise and its possible effects on planetary detections. We conclude with estimates of the expected detection rates for future wide-angle synoptic surveys.
description: 24 pages, 16 figures, ApJ in press
Groups which are not properly 3-realizable
Creators: name: Funar, Louis
name: Lasheras, Francisco F.
name: Repovs, Dusan
Publisher: name: arXiv
Year: 2007
Subjects: subject: Geometric Topology (math.GT)
subject: Group Theory (math.GR)
subject: FOS: Mathematics
subject: 57M50, 57M10, 57M30

description: A group is properly 3-realizable if it is the fundamental group of a compact polyhedron whose universal covering is proper homotopically equivalent to some 3-manifold. We prove that when such a group is also quasi-simply filtered then it has {\em pro-(finitely generated free) fundamental group at infinity} and {\em semi-stable ends}. Conjecturally the quasi-simply filtration assumption is superfluous. Using these restrictions we provide the first examples of finitely presented groups which are not properly 3-realizable, for instance large families of Coxeter groups.
description: revised version, 16p
N-vaton
Creators: name: Huang, Qing-Guo
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: In general there are a large number of light scalar fields in the theories going beyond standard model, such as string theory, and some of them can be taken as the candidates of curvatons. For simplicity, we assume all of curvatons have the same decay rate and suddenly decay into radiation at the same time. In order to distinguish this scenario from the more general case, we call it "N-vaton". We use $δ{\cal N}$ formalism to calculate the primordial power spectrum and bispectrum in N-vaton model and investigate various bounds on the non-Gaussianity parameter $f_{NL}$. A red tilted primordial power spectrum and a large value of $f_{NL}$ can be naturally obtained if the curvature perturbation generated by inflaton also makes a significant contribution to the primordial power spectrum. As a realistic N-vaton model, we suppose that the axions in the KKLT compactifications of Type IIB string theory are taken as curvatons and a rich phenomenology is obtained.
description: 30 pages, 3 figures; minor corrections and refs added; clarifications and discussions added, version for publication in JCAP
Analiza mikrostrija na gleđi ljudskih zuba iz perioda mezolitsko-neolitske tranzicije sa teritorije centralnog Balkana i južnog dela Panonske nizije
Creators: name: Marković, Jelena
name: Romero, Alejandro
name: Stefanović, Sofija
Publisher: name: Zenodo
Year: 2019
Subjects: micro-striations
teeth
Neolithic transition
diet
Serbia

description: Jedna od najznačajnijih promena u ljudskoj prošlosti desila se u periodu mezolitsko – neolitske tranzicije, kada ljudi sa lovačko-sakupljačkog prelaze na sedelački način života i bavljenje poljoprivredom. Ovaj proces naziva se neolitska demografska tranzicija i značajno je uticao na biologiju ljudi i njihovu ishranu. Veliki potencijal za razumevanje ovih promena predstavlja analiza zuba koja omogućuje da saznamo npr. stepen abrzivnosti hrane, prisustvo proteina u ishrani na koje ukazuje zubni kamenac ili ugljenih hidrata koji utiču na pojavu karijesa. Pored makroskopskih metoda, postoje i mikroskopske analize zuba poput proučavanja mikrostrija na gleđi zuba, koje, takođe, pružaju značajan uvid u način ishrane mezolitsko-neolitskih zajednica. Mikrostrije nastaju kao posledica procesa mastikacije hrane. Naime, različite vrste namirnica sadrže drugačije abrazivne čestice koje čovek unosi u organizam zajedno sa hranom. Tako se, na primer, u biljkama nalaze fitoliti, na koži ribe silikatne čestice, a u mlevenom brašnu čestice kamena, koje sve mogu ostaviti mikroskopski vidljive tragove na zubima.

U ovom radu će biti prikazani preliminarni rezultati analize mikrostirija kod 40 individua iz perioda od 9500. do 5500 g. p.n.e., koje potiču sa teritorije Đerdapske klisure, južnog dela Panonske nizije i Šumadije. Za potrebe analize mikrostrija izrađeni su silikonski kalupi, pomoću kojih su napravljene replike zuba od epoksi smole. Dobijene replike analizirane su posmatranjem pod skenirajućim elektronskim mikroskopom.

Preliminarni rezultati pokazali su da postoji značajna razlika u obrascima mikrostrija između mezolitskih i neolitskih zuba. Na mezolitskim zubima uočeni su kompleksniji obrasci sa većim brojem mikrostrija, što upućuje na zaključak da su se ljudi u mezolitu hranili mnogo abrazivnijom hranom od ljudi u neolitu. Ovakav rezultat može biti rezultat promene u vrsti i načinu obrade hrane u neolitu.
title: Investigation of the surface roughness of aluminium composite in the drilling process
Creators: name: Kishore,  Gundugandla
name: Parthiban, A.
name: Mohana Krishnan , A.
name: Radha Krishnan , B.
Publisher: name: Peter the Great St. Petersburg Polytechnic University
Year: 2021

description: This paper investigates the Surface roughness in the various Aluminium composite. The drilling experiment is performed on specimens Al7075 + 3% Al2O3, Al7075 + 3% Al2O3 + 1% Mica, Al7075 + 3% Al2O3 + 2% Mica, Al7075 + 3% Al2O3 + 3% Mica with high-speed steel twist drills of 5 mm diameter grade M2. ISO 234:1980 is the specification of the drills used in the current work. The drilling experiment takes place with a feed speed of 0.5 mm/rev. For the aluminum composite samples with coolant, the cutting speed is at different speeds of 10, 20, and 30 mm/min. The Surface Measuring Unit of the Stylus type is used to locate the Surface Roughness Ra of the drilled hole surface. The number of iterations completed is five times for the repeatability of effects with the same drilling parameters. The surface roughness had increased with the addition of reinforcement. The 2% mica addition showed a better surface finish than the 3% addition. Scanning Electron Microscopy investigated the Surface Morphological characteristics.
D5.5 Community Building Report
Creators: name: Declerck, Thierry
name: McCrae, John P.
name: Gracia, Jorge
name: Bosque-Gil, Julia
Publisher: name: Zenodo
Year: 2021

description: This is the second deliverable reporting on activities pursued in the context of Task 5.4. “Community Building”, which is a part of WP5 “Language Resource and Service Sustainability”. While there might be some overlap with activities reported in the first version of this report (D.5.4), the focus is on activities taking place in the time between January 2020 and March 2021.
Inertial modes of rigidly rotating neutron stars in Cowling approximation
Creators: name: Kastaun, Wolfgang
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: In this article, we investigate inertial modes of rigidly rotating neutron stars, i.e. modes for which the Coriolis force is dominant. This is done using the assumption of a fixed spacetime (Cowling approximation). We present frequencies and eigenfunctions for a sequence of stars with a polytropic equation of state, covering a broad range of rotation rates. The modes were obtained with a nonlinear general relativistic hydrodynamic evolution code. We further show that the eigenequations for the oscillation modes can be written in a particularly simple form for the case of arbitrary fast, but rigid rotation. Using these equations, we investigate some general characteristics of inertial modes, which are then compared to the numerically obtained eigenfunctions. In particular, we derive a rough analytical estimate for the frequency as a function of the number of nodes of the eigenfunction, and find that a similar empirical relation matches the numerical results with unexpected accuracy. We investigate the slow rotation limit of the eigenequations, obtaining two different sets of equations describing pressure and inertial modes. For the numerical computations we only considered axisymmetric modes, while the analytic part also covers nonaxisymmetric modes. The eigenfunctions suggest that the classification of inertial modes by the quantum numbers of the leading term of a spherical harmonic decomposition is artificial in the sense that the largest term is not strongly dominant, even in the slow rotation limit. The reason for the different structure of pressure and inertial modes is that the Coriolis force remains important in the slow rotation limit only for inertial modes. Accordingly, the scalar eigenequation we obtain in that limit is spherically symmetric for pressure modes, but not for inertial modes.
description: 13 pages, 10 figures Fixed some typos, reformulated a few paragraphs, added 3 references
Symmetry Relations for Trajectories of a Brownian Motor
Creators: name: Astumian, R. Dean
Publisher: name: arXiv
Year: 2007
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: A Brownian Motor is a nanoscale or molecular device that combines the effects of thermal noise, spatial or temporal asymmetry, and directionless input energy to drive directed motion. Because of the input energy, Brownian motors function away from thermodynamic equilibrium and concepts such as linear response theory, fluctuation dissipation relations, and detailed balance do not apply. The {\em generalized} fluctuation-dissipation relation, however, states that even under strongly thermodynamically non-equilibrium conditions the ratio of the probability of a transition to the probability of the time-reverse of that transition is the exponent of the change in the internal energy of the system due to the transition. Here, we derive an extension of the generalized fluctuation dissipation theorem for a Brownian motor for the ratio between the probability for the motor to take a forward step and the probability to take a backward step.
One-loop energy-momentum tensor in QED with electric-like background
Creators: name: Gavrilov, S. P.
name: Gitman, D. M.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We have obtained nonperturbative one-loop expressions for the mean energy-momentum tensor and current density of Dirac's field on a constant electric-like background. One of the goals of this calculation is to give a consistent description of back-reaction in such a theory. Two cases of initial states are considered: the vacuum state and the thermal equilibrium state. First, we perform calculations for the vacuum initial state. In the obtained expressions, we separate the contributions due to particle creation and vacuum polarization. The latter contributions are related to the Heisenberg-Euler Lagrangian. Then, we study the case of the thermal initial state. Here, we separate the contributions due to particle creation, vacuum polarization, and the contributions due to the work of the external field on the particles at the initial state. All these contributions are studied in detail, in different regimes of weak and strong fields and low and high temperatures. The obtained results allow us to establish restrictions on the electric field and its duration under which QED with a strong constant electric field is consistent. Under such restrictions, one can neglect the back-reaction of particles created by the electric field. Some of the obtained results generalize the calculations of Heisenberg-Euler for energy density to the case of arbitrary strong electric fields.
description: 35 pages; misprints in the sign in definitions (40)-(43), and (68) corrected, results unchanged
Stringy Motivic Spectra
Creators: name: Buchanan, Ryan J.
Publisher: name: Zenodo
Year: 2023
Subjects: string theory
strings
cohomology
spectra
loop spaces
branes
braneworld cosmology
cosmology
realization
quantum
superalgebra
qft

description: We consider strings from the perspective of stable motivic, homotopical QFT. Some predictions for the behavior of gauginos in both a Minkowski light cone and $5$-dimensional $\mathcal{A}d\mathcal{S}_5$-space are given. We show that there is a duality between working locking in a system of dendrites, and threshold edging at the periphery of a manifold.                This work extends the work of [4] and [7] by providing a more mathematical interpretation of the realization of quasi-quanta in open topological dynamical systems. This interpretation incidentally involves the category of pure motives over $\mathfrak{C}$, and projections of fiber spectra to the category of stable homotopies.
Comparison of numerical methods for computing the repeated Compton scattering of photons in isotropic media
Creators: name: Acharya, Sandeep Kumar
name: Chluba, Jens
name: Sarkar, Abir
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Repeated Compton scattering of photons with thermal electrons is one of the fundamental processes at work in many astrophysical plasma. Solving the exact evolution equations is hard and one common simplification is based on Fokker-Planck (FP) approximations of the Compton collision term. Here we carry out a detailed numerical comparison of several FP approaches with the exact scattering kernel solution for a range of test problems assuming isotropic media and thermal electrons at various temperatures. The Kompaneets equation, being one of the most widely used FP approximations, fails to account for Klein-Nishina corrections and enhanced Doppler boosts and recoil at high energies. These can be accounted for with an alternative FP approach based on the exact first and second moments of the scattering kernel. As demonstrated here, the latter approach works very well in dilute media, but inherently fails to reproduce the correct equilibrium solution in the limit of many scattering. Conditions for the applicability of the FP approximations are clarified, overall showing that the Kompaneets equation provides the most robust approximation to the full problem, even if inaccurate in many cases. We close our numerical analysis by briefly illustrating the solutions for the spectral distortions of the cosmic microwave background (CMB) after photon injection at redshift $z\lesssim 10^5$, when double Compton and Bremsstrahlung emission can be omitted. We demonstrate that the exact treatment using the scattering kernel computed with {\tt CSpack} is often needed. This work should provide an important step towards accurate computations of the CMB spectral distortions from high-energy particle cascades.
description: Comments welcome
“To boldly go where no series has gone before”. Star Trek - The Original Series in Italia: il linguaggio della tecno-scienza, il doppiaggio, la fortuna
Creators: name: Iannuzzi, Giulia
Publisher: name: Università degli Studi di Cagliari
Year: 2014

description: Al centro del saggio vi è un'analisi critica del doppiaggio italiano di Star Trek – The Original Series, andata in onda negli USA tra 1966 e 1969 e giunta in Italia nel 1979.L'analisi del doppiaggio affronta il problema della traduzione in senso ampiamente culturale (sulla scorta di studi come quelli di Even-Zohar e Venuti), adoperando il caso di una delle serie fantascientifiche più famose nella storia del medium televisivo per esemplificare più ampie dinamiche traduttive della fantascienza statunitense in Italia, nonché il difficile rapporto - nel contesto culturale italiano - tra cultura umanistica e scientifica (si vedano su questo i contributi di Pierpaolo Antonello), a cui si può ricondurre il fenomeno di semplificazione e livellamento verso il basso del gergo tecno-scientifico che ha caratterizzato le prime traduzioni della serie.Il generale depotenziamento della sfera linguisto-lessicale tecnico-scientifica, tanto più rimarchevole vista l'importanza del linguaggio nella costruzione dell'identità e della fortuna della serie originale, si può far risalire in parte a un'idea di pubblico culturalmente più impreparato dell'omologo statunitense, in parte a una più generale trascuratezza nei processi produttivi dell'emittente e della cooperativa di doppiaggio coinvolte (TMC e ADC), entrambi sintomi di una visione del prodotto culturale televisivo in termini di mero consumo, tipica di un'epoca che precedeva la new golden age della televisione americana, e forse non ancora estranea al contesto italiano corrente (come hanno dimostrato, per altri casi, studi di Buonomo, Izzo e Scarpino, Ranzato).Il caso di studio è contestualizzato da alcuni cenni iniziali sul più ampio tema della traduzione delle serie televisive fantascientifiche americane in Italia tra anni Cinquanta e Settanta, e completato da una ricognizione delle prime fortune della serie a cavallo di diversi media nella penisola.Star Trek, al centro di un franchise tra i più redditizi del pianeta e di uno dei fandom più organizzati e creativi (di cui si è occupato anche Herny Jenkins a più riprese), giunse in Italia negli anni Settanta anche con novellizzazioni e prodotti derivati. Il fandom nostrano si organizzò precocemente e, dimostrando una capacità di iniziativa e preparazione culturale non comuni, protestò per la scarsa qualità dei primi doppiaggi e ottenne la supervisione di molte traduzioni seguenti.
description: Between, Vol 4, N° 8 (2014): Tecnologia, immaginazione e forme del narrare
New Black Holes in Five Dimensions
Creators: name: Lu, H.
name: Mei, Jianwei
name: Pope, C. N.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We construct new stationary Ricci-flat metrics of cohomogeneity 2 in five dimensions, which generalise the Myers-Perry rotating black hole metrics by adding a further non-trivial parameter. We obtain them via a construction that is analogous to the construction by Plebanski and Demianski in four dimensions of the most general type D metrics. Limiting cases of the new metrics contain not only the general Myers-Perry black hole with independent angular momenta, but also the single rotation black ring of Emparan and Reall. In another limit, we obtain new static metrics that describe black holes whose horizons are distorted lens spaces L(n;m)= S^3/Γ(n;m), where m\ge n+2\ge 3. They are asymptotic to Minkowski spacetime factored by Γ(m;n). In the general stationary case, by contrast, the new metrics describe spacetimes with an horizon and with a periodicity condition on the time coordinate; these examples can be thought of as five-dimensional analogues of the four-dimensional Taub-NUT metrics.
description: 25 pages
Smallest Remnants of Early Matter Domination
Creators: name: Barenboim, Gabriela
name: Blinov, Nikita
name: Stebbins, Albert
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The evolution of the universe prior to Big Bang Nucleosynthesis could have gone through a phase of early matter domination (EMD) which enhanced the growth of small-scale dark matter structure. If EMD was long enough, self-gravitating objects formed prior to reheating. We study the evolution of these dense early halos (EHs) through reheating. At the end of EMD, EHs undergo rapid expansion and eventually eject their matter. We find that this process washes out structure on scales much larger than naively expected from the size of the original halos. We compute the density profiles of the EH remnants and use them to construct late-time power spectra that include these non-linear effects. EH dynamics limits the maximum enhancement that can be generated by EMD in a way that is independent of the dark matter microphysics. We evolve an extrapolated $Λ$CDM power spectrum to estimate the properties of microhalos that would form after matter-radiation equality. Surprisingly, cosmologies with a short period of EMD lead to an earlier onset of microhalo formation compared to those with a long period of EMD. In either case, dark matter structure formation begins much earlier than in the standard cosmology, with most DM bound in microhalos.
description: 28+15 pages, 14 figures. Expanded discussion to match the published version
Relaxed Three-Algebras: Their Matrix Representations and Implications for Multi M2-brane Theory
Creators: name: Ali-Akbari, M.
name: Sheikh-Jabbari, M. M.
name: Simon, J.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We argue that one can relax the requirements of the non-associative three-algebras recently used in constructing D=3, N=8 superconformal field theories, and introduce the notion of ``relaxed three-algebras''. We present a specific realization of the relaxed three-algebras in terms of classical Lie algebras with a matrix representation, endowed with a non-associative four-bracket structure which is prescribed to replace the three-brackets of the three-algebras. We show that both the so(4)-based solutions as well as the cases with non-positive definite metric find a uniform description in our setting. We discuss the implications of our four-bracket representation for the D=3, N=8 and multi M2-brane theory and show that our setup can shed light on the problem of negative kinetic energy degrees of freedom of the Lorentzian case.
description: 31 pages, no figures
Casimir Forces in a Piston Geometry at Zero and Finite Temperatures
Creators: name: Hertzberg, M. P.
name: Jaffe, R. L.
name: Kardar, M.
name: Scardicchio, A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Quantum Physics (quant-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study Casimir forces on the partition in a closed box (piston) with perfect metallic boundary conditions. Related closed geometries have generated interest as candidates for a repulsive force. By using an optical path expansion we solve exactly the case of a piston with a rectangular cross section, and find that the force always attracts the partition to the nearest base. For arbitrary cross sections, we can use an expansion for the density of states to compute the force in the limit of small height to width ratios. The corrections to the force between parallel plates are found to have interesting dependence on the shape of the cross section. Finally, for temperatures in the range of experimental interest we compute finite temperature corrections to the force (again assuming perfect boundaries).
description: Updated to match version published in PRD, 13 pages, 5 figures
Performance analysis of a memory ARQ scheme with soft decision detectors
Creators: name: Lau, Chiew Tong
Publisher: name: University of British Columbia
Year: 2010

description: An automatic repeat request (ARQ) scheme with memory and soft error detectors has been recently proposed by Benelli. Its performance was studied mainly through computer simulation. In this thesis, a generalized version of this ARQ scheme is examined. The selection of certain thresholds and weights to minimize the bit error rate in systems using a fixed number of packet repeats is considered. The evaluation of the average number of transmissions per packet in systems in which negatively acknowledged packets are retransmitted until successfully received is described. Finally, the performance of the memory ARQ scheme with forward error correction is analyzed.
EarGate: Gait-based User Identification with In-ear Microphones
Creators: name: Ferlini, Andrea
name: Ma, Dong
name: Harle, Robert
name: Mascolo, Cecilia
Publisher: name: arXiv
Year: 2021
Subjects: subject: Human-Computer Interaction (cs.HC)
subject: FOS: Computer and information sciences

description: Human gait is a widely used biometric trait for user identification and recognition. Given the wide-spreading, steady diffusion of ear-worn wearables (Earables) as the new frontier of wearable devices, we investigate the feasibility of earable-based gait identification. Specifically, we look at gait-based identification from the sounds induced by walking and propagated through the musculoskeletal system in the body. Our system, EarGate, leverages an in-ear facing microphone which exploits the earable's occlusion effect to reliably detect the user's gait from inside the ear canal, without impairing the general usage of earphones. With data collected from 31 subjects, we show that EarGate achieves up to 97.26% Balanced Accuracy (BAC) with very low False Acceptance Rate (FAR) and False Rejection Rate (FRR) of 3.23% and 2.25%, respectively. Further, our measurement of power consumption and latency investigates how this gait identification model could live both as a stand-alone or cloud-coupled earable system.
description: MobiCom 2021
Dynamical percolation on general trees
Creators: name: Khoshnevisan, Davar
Publisher: name: arXiv
Year: 2007
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: Primary. 60K35; Secondary. 31C15, 60J45

description: Häggström, Peres, and Steif (1997) have introduced a dynamical version of percolation on a graph $G$. When $G$ is a tree they derived a necessary and sufficient condition for percolation to exist at some time $t$. In the case that $G$ is a spherically symmetric tree, Häggström, Peres, and Steif (1997) derived a necessary and sufficient condition for percolation to exist at some time $t$ in a given target set $D$. The main result of the present paper is a necessary and sufficient condition for the existence of percolation, at some time $t\in D$, in the case that the underlying tree is not necessary spherically symmetric. This answers a question of Yuval Peres (personal communication). We present also a formula for the Hausdorff dimension of the set of exceptional times of percolation.
description: 24 pages; to appear in Probability Theory and Related Fields
Earth-abundant photovoltaic materials
Creators: name: Wright, Lewis
Publisher: name: Loughborough University
Year: 2021
Subjects: subject: 91399 Mechanical Engineering not elsewhere classified
subject: FOS: Mechanical engineering

description: Research grade photovoltaic devices made from inorganic compounds such as CdTe and Cu(In,Ga)Se2 are steadily progressing towards the thermodynamic limit, and as such have moved into commercial production. However, these compounds contain elements that are either toxic, scarce, or used in other high-demand products, making them potentially problematic for long-term mass production of photovoltaic modules. This thesis investigates three different compounds made from earth abundant elements as potential alternatives to the established thin film technologies.
The kesterite Cu2ZnSnSe4 is widely lauded for its abundance, low toxicity, and ideal/tuneable optoelectronic properties. Here, to build on its compositional advantages, an industrially scalable spray pyrolysis deposition technique is used to produce Cu2ZnSnSe4 absorber layers for photovoltaic devices. In the first work chapter this leads to a brand-new water-based solution, utilising the amine-thiol mixture solvent system, which produced an in-house record 6.8% device efficiency. This not only shows the promise of spray deposition for cheap-to-produce devices, but that objectively non-toxic solvents can be used to dissolve precursors, another boon to mass production.
Despite being an in-house record efficiency this Cu2ZnSnSe4 device suffered from the open-circuit voltage deficit (Voc-deficit) characteristic of kesterites. The source of this deficit is unknown and prevents not only efficiency improvements but also interest in mass-production. In the second work chapter a hypothesis is presented for the root cause of the Voc-deficit, specifically that Sn’s multivalence is responsible for defects deep in the bandgap that limit the Voc and ultimately the efficiency. To test this hypothesis is the first recorded attempt at forming the kesterite Cu2ZnZrSe4, replacing multivalent Sn with monovalent Zr. Combinatorial sputtering is used to quickly traverse this new, large, quaternary compositional phase space.
While attempting to produce a new quaternary material, the pseudo-binary phase Cu-doped ZnSe was found to reliably form, with a favourable 1.3eV bandgap and photoluminescence an order of magnitude larger than the inhouse record kesterite device. In the third work chapter is a preliminary investigation of this Cu:ZnSe phase, again with combinatorial sputtering to quickly traverse the phase space.
Additional file 1 of Neonatal and child mortality data in retrospective population-based surveys compared with prospective demographic surveillance: EN-INDEPTH study
Creators: name: Tryphena Nareeba
name: Dzabeng, Francis
name: Alam, Nurul
name: Gashaw A. Biks
name: Thysen, Sanne M.
name: Akuze, Joseph
name: Blencowe, Hannah
name: Stephane Helleringer
name: Lawn, Joy E.
name: Kaiser Mahmud
name: Temesgen Azemeraw Yitayew
name: Fisker, Ane B.
Publisher: name: figshare
Year: 2021
Subjects: subject: Medicine
subject: Biotechnology
subject: Sociology
subject: FOS: Sociology
subject: Immunology
subject: FOS: Clinical medicine
subject: Cancer
subject: Science Policy

description: Additional file 1. Additional methods. 1.1: Description of key differences between the HDSS sites. 1.2: Illustration of how observation time is counted in the EN-INDEPTH survey and different HDSS sites. 1.3: Additional methods for objective 2.
Groups of Operators for Evolution Equations of Quantum Many-Particle Systems
Creators: name: Gerasimenko, V. I.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Physics (quant-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Mathematical Physics (math-ph)
subject: Analysis of PDEs (math.AP)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: The aim of this work is to study the properties of groups of operators for evolution equations of quantum many-particle systems, namely, the von Neumann hierarchy for correlation operators, the BBGKY hierarchy for marginal density operators and the dual BBGKY hierarchy for marginal observables. We show that the concept of cumulants (semi-invariants) of groups of operators for the von Neumann equations forms the basis of the expansions for one-parametric families of operators for evolution equations of infinitely many particles.
description: 16 pages
Dimensional crossover in a spin liquid to helimagnet quantum phase transition
Creators: name: Garlea, V. O.
name: Zheludev, A.
name: Habicht, K.
name: Meissner, M.
name: Grenier, B.
name: Regnault, L. -P.
name: Ressouche, E.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Neutron scattering is used to study magnetic field induced ordering in the quasi-1D quantum spin-tube compound Sul--Cu$_2$Cl$_4$ that in zero field has a non-magnetic spin-liquid ground state. The experiments reveal an incommensurate chiral high-field phase stabilized by a geometric frustration of the magnetic interactions. The measured critical exponents $β\approx0.235$ and $ν\approx0.34$ at $H_c\approx3.7$ T point to an unusual sub-critical scaling regime and may reflect the chiral nature of the quantum critical point.
description: 4 pages
Metric mechanics with non-trivial topology: actuating irises, cylinders and evertors
Creators: name: Duffy, D.
name: Javed, M.
name: Abdelrahman, M. K.
name: Ware, T. H.
name: Warner, M.
name: Biggins, J. S.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: Liquid crystal elastomers contract along their director on heating and recover on cooling, offering great potential as actuators and artificial muscles. If a flat sheet is programmed with a spatially varying director pattern, it will actuate into a curved surface, allowing the material to act as a strong machine such as a grabber or lifter. Here we study the actuation of programmed annular sheets which, owing to their central hole, can sidestep constraints on area and orientation. We systematically catalogue the set of developable surfaces encodable via axisymmetric director patterns, and uncover several qualitatively new modes of actuation, including cylinders, irises, and everted surfaces in which the inner boundary becomes the outer boundary after actuation. We confirm our designs with a combination of experiments and numerics. Many of our actuators can re-attain their initial inner or outer radius upon completing actuation, making them particularly promising, as they can avoid potentially problematic stresses in their activated state even when fixed onto a frame or pipe.
description: 9 pages, 4 figures, accepted version
D3.6 Stakeholder Engagement Strategy
Creators: name: LIBER
Publisher: name: Zenodo
Year: 2021
Subjects: CoBraD
Stakeholder Engagement
Medical device
Real World Data
Funded Research

description: This report (D3.6) outlines the Stakeholder Engagement Strategy for the MES-CoBraD project. It acts as
 a reference point for how each stakeholder group can be understood, approached, and engaged
 throughout the course of the project. In addition, actions are established to begin a successful starting
 point for creating meaningful engagement. The primary objective of MES-CoBraD (Multidisciplinary Expert System for the Assessment & Management
 of Complex Brain Disorders) is to improve diagnostic accuracy and therapeutic outcomes in people with
 Complex Brain Disorders (CoBraD), as reflected in the Neurocognitive (Dementia), Sleep, and Seizure
 (Epilepsy) disorders and their interdependences through Real-World Data (RWD) from multiple clinical
 and consumer sources through comprehensive, cost-efficient, and fast protocols, in light of the MESCoBraD Agreement and associated challenges.
ความพร้อมด้านทรัพยากรมนุษย์ การมุ่งเน้นตลาด และความสามารถขององค์กร : สร้างความเป็นนานาชาติของวิสาหกิจขนาดกลางและขนาดย่อมในประเทศไทย - ตามแนวคิดฐานทรัพยากร
Creators: name: ชลธิชา มธุรเมธา
Publisher: name: คณะพาณิชยศาสตร์และการบัญชี มหาวิทยาลัยธรรมศาสตร์
Year: 2014
Subjects: ความพร้อมด้านทรัพยากรมนุษย์, การมุ่งเน้นตลาด, ความสามารถขององค์กร, ความเป็นนานาชาติของวิสาหกิจขนาดกลางและขนาดย่อม

description: 144 (ต.ค.-ธ.ค. 57), 37, วารสารบริหารธุรกิจ JBA
Impact de l'environnement Macroéconomique sur le coût du capital des entreprises marocaines cotées en bourse
Creators: name: LAMGHARI, Sana
Publisher: name: Zenodo
Year: 2023
Subjects: Coût du capital ; modèle multifactoriel ; risques ; déterminants macroéconomiques ; marché financier.

description: L’entreprise est une unité appartenant à son système financier et macroéconomique. Par conséquent, elle ne peut pas être évaluée indépendamment de son environnement. La problématique du coût du capital est liée à la fois à l’environnement interne et externe de l’entreprise. En d’autres termes, le coût du capital d’une entreprise ne peut pas être estimé uniquement sur la base de ses indicateurs financiers, il dépend également des risques encourus sur le plan macroéconomique. Le coût du capital influence la nature et le niveau des investissements réalisés par l’entreprise puisque l’évaluation de ces projets nécessite une connaissance préalable du coût du capital afin de mesurer la valeur créée et le taux de rentabilité actuarial d’investissement. L’objectif de ce travail est la recherche des déterminants macroéconomiques du coût du capital des entreprises marocaines cotées en bourse de Casablanca. Les travaux empiriques qui ont constitué une base de ce travail de recherche, sont principalement les fondements empiriques de l’Arbitrage Pricing Theory « APT » en tant que modèle d’évaluation des actifs financiers basé sur des facteurs macroéconomiques influençant la rentabilité des actifs financiers.
Galaxy Zoo Builder: Morphological Dependence of Spiral Galaxy Pitch Angle
Creators: name: Lingard, Timothy
name: Masters, Karen L.
name: Krawczyk, Coleman
name: Lintott, Chris
name: Kruk, Sandor
name: Simmons, Brooke
name: Keel, William
name: Nichol, Robert
name: Baeten, Elisabeth
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Spiral structure is ubiquitous in the Universe, and the pitch angle of arms in spiral galaxies provide an important observable in efforts to discriminate between different mechanisms of spiral arm formation and evolution. In this paper, we present a hierarchical Bayesian approach to galaxy pitch angle determination, using spiral arm data obtained through the Galaxy Builder citizen science project. We present a new approach to deal with the large variations in pitch angle between different arms in a single galaxy, which obtains full posterior distributions on parameters. We make use of our pitch angles to examine previously reported links between bulge and bar strength and pitch angle, finding no correlation in our data (with a caveat that we use observational proxies for both bulge size and bar strength which differ from other work). We test a recent model for spiral arm winding, which predicts uniformity of the cotangent of pitch angle between some unknown upper and lower limits, finding our observations are consistent with this model of transient and recurrent spiral pitch angle as long as the pitch angle at which most winding spirals dissipate or disappear is larger than 10 degrees.
Lower-limb kinematics and kinetics during continuously varying human locomotion
Creators: name: Reznick, Emma
name: Embry, Kyle R.
name: Neuman, Ross
name: Bolívar-Nieto, Edgar
name: Fey, Nicholas P.
name: Gregg, Robert D.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: Human locomotion involves continuously variable activities including walking, running, and stair climbing over a range of speeds and inclinations as well as sit-stand, walk-run, and walk-stairs transitions. Understanding the kinematics and kinetics of the lower limbs during continuously varying locomotion is fundamental to developing robotic prostheses and exoskeletons that assist in community ambulation. However, available datasets on human locomotion neglect transitions between activities and/or continuous variations in speed and inclination during these activities. This data paper reports a new dataset that includes the lower-limb kinematics and kinetics of ten able-bodied participants walking at multiple inclines ($\pm$ 0, 5, 10 $^{\circ}$) and speeds (0.8, 1, 1.2 m/s), running at multiple speeds (1.8, 2, 2.2, 2.4 m/s), walking and running with constant acceleration ($\pm$ 0.2, 0.5 $\text{m/s^2}$), and stair ascent/descent with multiple stair inclines (20, 25, 30, 35 $^{\circ}$). This dataset also includes sit-stand transitions, walk-run transitions, and walk-stairs transitions. Data were recorded by a Vicon motion capture system and, for applicable tasks, a Bertec instrumented treadmill.
The log-linear group-lasso estimator and its asymptotic properties
Creators: name: Nardi, Yuval
name: Rinaldo, Alessandro
Publisher: name: arXiv
Year: 2007
Subjects: subject: Statistics Theory (math.ST)
subject: FOS: Mathematics

description: We define the group-lasso estimator for the natural parameters of the exponential families of distributions representing hierarchical log-linear models under multinomial sampling scheme. Such estimator arises as the solution of a convex penalized likelihood optimization problem based on the group-lasso penalty. We illustrate how it is possible to construct an estimator of the underlying log-linear model using the blocks of nonzero coefficients recovered by the group-lasso procedure. We investigate the asymptotic properties of the group-lasso estimator as a model selection method in a double-asymptotic framework, in which both the sample size and the model complexity grow simultaneously. We provide conditions guaranteeing that the group-lasso estimator is model selection consistent, in the sense that, with overwhelming probability as the sample size increases, it correctly identifies all the sets of nonzero interactions among the variables. Provided the sequences of true underlying models is sparse enough, recovery is possible even if the number of cells grows larger than the sample size. Finally, we derive some central limit type of results for the log-linear group-lasso estimator.
description: Published in at http://dx.doi.org/10.3150/11-BEJ364 the Bernoulli (http://isi.cbs.nl/bernoulli/) by the International Statistical Institute/Bernoulli Society (http://isi.cbs.nl/BS/bshome.htm)
Additional file 2 of Neonatal and child mortality data in retrospective population-based surveys compared with prospective demographic surveillance: EN-INDEPTH study
Creators: name: Tryphena Nareeba
name: Dzabeng, Francis
name: Alam, Nurul
name: Gashaw A. Biks
name: Thysen, Sanne M.
name: Akuze, Joseph
name: Blencowe, Hannah
name: Stephane Helleringer
name: Lawn, Joy E.
name: Kaiser Mahmud
name: Temesgen Azemeraw Yitayew
name: Fisker, Ane B.
Publisher: name: figshare
Year: 2021
Subjects: subject: Medicine
subject: Biotechnology
subject: Sociology
subject: FOS: Sociology
subject: Immunology
subject: FOS: Clinical medicine
subject: Cancer
subject: Science Policy

description: Additional file 2. STROBE guidelines checklist.