Miracle-dz/UniFAR-FTUs huggingface dataset:
Automated 3D region-based volumetric estimation of optic disc swelling in papilledema using spectral-domain optical coherence tomography

The six-stage Frisén scale is a qualitative and subjective method for assessing papilledema (optic disc swelling due to raised intracranial pressure) using fundus photographs. The recent introduction of spectral-domain optical coherence tomography (SD-OCT) presents a promising alternative to enable the 3-D quantitative estimation of papilledema. In this work, we propose an automated region-based volumetric estimation of the degree of papilledema from SD-OCT. After using a custom graph-based approach to segment the surfaces of the swollen optic nerve head, the volumes of the nasal, superior, temporal, and inferior regions are computed. Using a dataset of 70 SD-OCT optic-nerve-head (ONH) SD-OCT scans the Spearman rank correlation coefficients between expert-defined Frisén scale grades and the total retinal (TR) volume, nasal, superior, temporal, inferior regional volumes were 0.737, 0.752, 0.747, 0.770 and 0.758, respectively. Also, a fuzzy k-nearest-neighbor (k-NN) algorithm was used to predict Frisén scale grades (in a leave-one-subject-out fashion). Using multiple features rather than just the TR volume made the resulting mean Frisén grade difference (MGD) between the expert-defined grades 0.386 (down from 0.629) and prediction accuracy 64.29% (up from 41.43%).
Magnetic Field Amplification by Shocks in Turbulent Fluids

We consider the effect of preexisting, large-scale, broadband turbulent density fluctuations on propagating hydromagnetic shock waves. We present results from several numerical simulations that solve the two-dimensional magnetohydrodynamic equations. In our simulations, a plasma containing large-scale, low-amplitude density and magnetic field turbulence is forced to flow into a rigid wall, forming a shock wave. We find that the density fluctuations not only distort the shape of the shock front and lead to a turbulent postshock fluid, but they also produce a number of important changes in the postshock magnetic field. The average downstream magnetic field is increased significantly, and large fluctuations in the magnetic vector occur, with the maximum field strength reaching levels such that magnetic stresses are important in the postshock region. The downstream field enhancement can be understood in terms of the stretching and forcing together of the magnetic field entrained within the turbulent fluid of the postshock flow. We suggest that these effects of the density fluctuations on the magnetic field are observed in astrophysical shock waves such as supernova blast waves and the heliospheric termination shock.
Joint statistics of the scalar gradient and the velocity gradient in turbulence using linear diffusion models

A model for the evolution of scalar gradients in turbulence is proposed. The molecular diffusion is approximated by a linear estimation, while the straining term is closed taking advantage of a previous model for velocity gradients [J. Martin, C. Dopazo, and L. Valino, “Dynamics of velocity gradient invariants in turbulence: Restricted Euler and linear diffusion models,” Phys. Fluids 10, 2012 (1998)]. The joint statistics of the scalar gradients and velocity gradients obtained from this model are studied. In particular, the alignment of the scalar gradient with the principal strain axis, and the correlations between the strain rate and the scalar dissipation rate are investigated. The results show reasonably good agreement with data from direct numerical simulation, which indicates that this simple model captures the essential geometrical properties of the scalar-gradient/velocity-gradient coupling in turbulent flows.
Curves As Parameters, and Touch Estimation

The aims of this paper are two-fold: to make clear that certain problems of interpretation which arise in estimating power spectra of stationary time series are entirely analogous to problems of interpretation which arise in carrying out two very elementary and classical statistical procedures, and to develop new concepts of estimation which clarify the interpretation of all three instances. En route, we shall have to give some attention to relation of asymptotic results to practical application. The nature of the argument with which we are concerned is such that it seems best to begin with two of the most classical situations of statistics, unrestricted regression and the construction of histograms, and to develop the necessary new concepts and attitudes as we progress step by step, rather than to introduce the new formal concepts before motivation and illustration are available. These concepts are stated, and the nature of the results obtained outlined, in the last section.
Oscillator strengths and radiative lifetimes for C2: Swan, Ballik-Ramsay, Phillips, and dΠg3←cΣu+3 systems

High level ab initio calculations, using multireference configuration interaction (MRCI) techniques, have been carried out to investigate the spectroscopic properties of the singlet AΠu1←XΣg+1 Phillips, the triplet dΠg3←aΣu3 Swan, the bΣg−3←aΠu3 Ballik-Ramsay, and the dΠg3←cΣu+3 transitions of C2. The MRCI expansions are based on full-valence complete active space self-consistent-field reference states and utilize the aug-cc-pV6Z basis set to resolve valence electron correlation. Core and core-valence correlations and scalar relativistic energy corrections were also incorporated in the computed potential energy surfaces. Nonadiabatic and spin-orbit effects were explored and found to be of negligible importance in the calculations. Harmonic frequencies and rotational constants are typically within 0.1% of experiment. The calculated radiative lifetimes compare very well with the available experimental data. Oscillator strengths are reported for all systems: fv′v″, where 0⩽v⩽5.
Study of the X Rays Produced by a Vacuum Spark

The results of experiments on the x rays emitted by an energetic vacuum spark are presented. X-ray spectroscopic studies show, in addition to the characteristic x-ray lines of the electrode metal, lines originating from very high stages of ionization of the element. In particular, lines of the 1s2–1snp sequence in the helium-like spectra Ti xxi through Ni xxvii, and the 1s–2p transition in Fe xxvi, were observed. Pinhole photography and time-resolved studies of the total x-ray emission indicate that these highly ionized species originate in a small, hot region between the two electrodes, which is produced by a pinch in a plasma of evaporated anode metal.
LYAPUNOV EXPONENTS FOR SMALL RANDOM PERTURBATIONS OF HAMILTONIAN SYSTEMS

Consider the stochastic nonlinear oscillator equation \[ \ddot{x} = -x -x^3 + \varepsilon^2 \beta \dot{x} + \varepsilon \sigma x \dot{W}_t \] with $\beta < 0$ and $\sigma \neq 0$. If $4\beta + \sigma^2 > 0$ then for small enough $\varepsilon > 0$ the system $(x,\dot{x})$ is positive recurrent in ${\bf R}^2 \setminus \{(0,0\}$. Now let $\overline{\lambda}(\varepsilon)$ denote the top Lyapunov exponent for the linearization of this equation along trajectories. The main result asserts that \[ \overline{\lambda}(\varepsilon) = \varepsilon^{2/3}\overline{\lambda} + O(\varepsilon^{4/3}) \qquad\mbox{as}\ \varepsilon \to 0 \] with $\overline{\lambda} > 0$. This result depends crucially on the fact that the system above is a small perturbation of a Hamiltonian system. The method of proof can be applied to a more general class of small perturbations of two-dimensional Hamiltonian systems. The techniques used include (i) an extension of results of Pinsky and Wihstutz for perturbations of nilpotent linear systems, and (ii) a stochastic averaging argument involving
Enrichments in Volatiles in Jupiter: A New Interpretation of the Galileo Measurements

Using an evolutionary model of the solar nebula, we fit all enrichments in volatiles with respect to the solar abundance measured in Jupiter by the Galileo probe. We argue that volatiles were trapped in the form of solid clathrate hydrates in the cooling feeding zone of Jupiter while the gas mass of the nebula was continuously decreasing with time. Enrichments in Jupiter are those acquired in planetesimals at the time of the hydrodynamic collapse of the feeding zone. The O/H ratio in Jupiter is predicted to be at least 8 times solar.
Compton profile study of gold: Theory and experiment

We present momentum densities and Compton profiles for gold calculated in the local‐density approximation (LDA) by use of the modified augmented plane wave (MAPW) self‐consistent scheme. Our theoretical calculations have been compared with our experimental Compton profile, measured at an intermediate resolution (0.40 a.u.) using 661.65 keV gamma‐rays. We have also compared our measurements with the APW calculations of Papanicolaou et al. It is seen that our LDA‐MAPW calculations with e––e– correlation correction are in better agreement with our experimental data. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Near-Field Ion Energy and Species Measurements of a 5-kW Hall Thruster

A molecular beam mass spectrometer has been used to determine the ion composition and energy distribution of the P5 5-kW class laboratory Hall thruster. A skimmer was used to obtain a sample of the plasma 10 cm downstream of the thruster exit plane. The thruster was operated at several discharge conditions and rotated with respect to the sampling skimmer in order to determine ion-energy pro les at various plume angles. These measurements were compared to data taken 75 cm from the discharge plane to examine the evolution of the ionenergy pro le and facility effects. Both ion-energy measurements and time-of- ight mass spectroscopy revealed evidence of singly, doubly, triply, and quadruply charged xenon ions within the plume. Ion-energy distributions were used to determine that the P5’s magnetic  eld is oriented such that the plumehas an overall inward focus. The ion-energy distributions taken 10 cm from the thruster had smaller full width at half maxima and less evidence of elastic collisions than those taken at 75 cm. Comparisonsmadewith laser-induced  uorescence data showed good agreement.
Barium borate optical parametric oscillator

Experimental results of the first BaB/sub 2/O/sub 4/ optical parametric oscillator (OPO) are presented. The pump source was the second harmonic output of a Q-switched TEM/sub 00/ mode Nd:YAG laser. The OPO had 1 mJ output energy with a peak power of 80 kW in a tuning range from 0.94 to 1.22 mu m. >
High-temperature effects of AlGaN/GaN high-electron-mobility transistors on sapphire and semi-insulating SiC substrates

The high-electron-mobility transistors (HEMTs) have been demonstrated on both sapphire and semi-insulating (SI) SiC substrates, and the dc characteristics of the fabricated devices were examined at temperatures ranging from 25 to 500 °C. The decrease in drain current and the transconductance with the increase of temperature have been observed. The decrease ratio of transconductance and drain current was similar for both the HEMTs on sapphire and SI–SiC substrates at and above 300 °C. The HEMTs on SiC substrates showed better dc characteristics after being subjected to thermal stress up to 500 °C. Although the SiC-based HEMTs showed better characteristics up to the temperature of 300 °C, compared with the sapphire-based HEMTs, similar dc characteristics were observed on both at and above 300 °C. For high-temperature applications (⩾300 °C), additional cooling arrangements are essential for both devices.
On The Complete Convergence Of Randomly Weighted Sums Of Random Fields

Abstract Let {Xn̲, n̲ ∊ V ⊆ℕd } be a d-dimensional random field indexed by some subset V of lattice ℕd, which are stochastically dominated by a random variable X. Let {an̲, i̲; n̲, i̲ ∊ V } be a 2d-dimensional random field independent of {Xn̲, n̲ ∊ V} and such that |an̲, i̲| M, n̲, i̲ ∊ V for some constant M. In this paper, we give conditions under which the following series is convergent for some real t, some fixed p > 0 and all ε > 0. Here |n̲| is used for Πdi=1 ni . The randomly indexed sums of field {Xn̲;n̲ ∊ V } are considered too
Radiative decays of B mesons at LHCb

This thesis is dedicated to the study of radiative decays of B mesons at LHCb. At quark level, such decays are a b→ sγ transition and take place via a penguin loop and are sensitive to virtual contribution of New Physics, which can be indicated by an increase in the decay rates. These decays also offer the possibility to test the V-A structure of the Standard Model coupling in the processes mediated by loop penguin diagrams. In the decay Bs → φγ, New Physics contribution can be probed by measuring the polarization of the photon in this decay. Systematic effects in the proper time reconstruction of the Bs in Bs → φγ can bias the photon polarization measurement in this decay, which will reduce the sensitivity on the relevant New Physics parameter. The author studied those effects and developed ideas to calibrate them using Bd → K∗γ and Bs → J/ψφ decays as control channels. These studies are mostly Monte Carlo based, due to a relatively small data set from the 2010 running. However, some studies and cross checks have indeed been performed with data. The author developed the trigger and stripping (another level of skimming the data, after the trigger) selections for Bs → φγ and Bd → K∗γ decays, and made a major contribution to the selection of the first significant sample of Bd → K∗γ from the 2010 data set of LHCb.
Stacking InAs islands and GaAs layers: Strongly modulated one‐dimensional electronic systems

With chemical beam epitaxy we stacked small InAs islands, separated by thin GaAs layers. Reflection electron diffraction during growth showed that after a seed‐layer growth, subsequent depositions require less InAs to form the islands. At 5 K the stacks have narrower luminescence peaks at lower energies than single island layers, and the stacks luminesce at room temperature. For 4‐nm‐high pyramidal islands with 20‐nm‐wide bases, we observed vertical periods down to 5.4 nm, small enough to couple quantum mechanically. The electronic structures possible for this class of objects should be sufficient for designing and observing room temperature quantum mechanical phenomena.
Electrical transport properties of aluminum-implanted 4H–SiC

The free hole density and low-field mobility of aluminum-doped 4H–SiC were investigated in the temperature range of 100–900K, both, experimentally and theoretically. Experimental data for implanted p-type 4H–SiC were compared with theoretical calculations using parameters determined for high-quality epitaxial layers. The deformation potential for intra- and intervalley scattering by acoustic phonons and the effective coupling constant for intra- and intervalley scattering by nonpolar optical phonons were determined. The detailed analysis of the implanted layers with aluminum-targeted concentration ranging from 3.33×1018to1021cm−3 shows that (i) about half of the implanted atoms are electrically active in the SiC lattice, (ii) a systematic compensation of about 10% of the doping level is induced by the implantation process, (iii) two different ionization energies for the aluminum atoms have to be used. Their origin is discussed in terms of inequivalent hexagonal and cubic lattice sites. Finally, the doping.
Observational Evidence of Active Galactic Nuclei Feedback

Radiation, winds, and jets from the active nucleus of a massive galaxy can interact with its interstellar medium, and this can lead to ejection or heating of the gas. This terminates star formation in the galaxy and stifles accretion onto the black hole. Such active galactic nuclei (AGN) feedback can account for the observed proportionality between the central black hole and the host galaxy mass. Direct observational evidence for the radiative or quasar mode of feedback, which occurs when AGN are very luminous, has been difficult to obtain but is accumulating from a few exceptional objects. Feedback from the kinetic or radio mode, which uses the mechanical energy of radio-emitting jets often seen when AGN are operating at a lower level, is common in massive elliptical galaxies. This mode is well observed directly through X-ray observations of the central galaxies of cool core clusters in the form of bubbles in the hot surrounding medium. The energy flow, which is roughly continuous, heats the hot intraclu.
Shadowing, expansiveness and hyperbolic homeomorphisms

Abstract The purpose of this paper is to complete results concerning the class ℋ of expansive homeomorphisms having the pseudo orbits tracing property on a compact metric space. We show that hyperbolic homeomorphisms introduced by Mañé in [8] are exactly those in the class ℋ then by the result of [12, 20] they form a class equal to the Smale space introduced by Ruelle in [18]. Next, assuming that the phase space is a smooth manifold, we show that a diffeomorphism is Anosov if and only if it is in the class ℋ and is a lower semi-continuity point of the map which assigns to any diffeomorphism the supremum of its expansive constants (possibly zero). Then we discuss the behavior of the dynamical systems generated by homeomorphisms from ℋ near their basic sets.
Control of induction motors via feedback linearization with input-output decoupling

In induction motor control, power efficiency is an important factor to be considered. We attempt to achieve both high dynamic performance and maximum power efficiency by means of linear decoupling of rotor speed (or motor torque) and rotor flux. The induction motor with our controller possesses the input-output dynamic characteristics of a linear system such that the rotor speed (or motor torque) and the rotor flux are decoupled. The rotor speed responses are not affected by abrupt changes in the rotor flux and vice versa. The rotor flux need not be measured but is estimated by the well known flux simulator. The effect of large variation in the rotor resistance on the control performances is minimized by employing a parameter adaptation method. To illuminate the significance of our work, we present simulation and experimental results as well as mathematical performance analyses. In particular, our experimental work demonstrates that recently developed nonlinear feedback control theories are of practical use.
Duality theory for covariant systems

If (A, p, G) is a covariant system over a locally compact group G, i.e. p is a homomorphism from G into the group of *-automorphisms of an operator algebra A, there is a new operator algebra W called the covariance algebra associated with (A, p, G). If A is a von Neumann algebra and p is a-weakly continuous, W is defined such that it is a von Neumann algebra. If A is a C*-algebra and p is norm-continuous W will be a C*-algebra. The following problems are studied in these two different settings: 1. If W is a covariance algebra, how do we recover A and p? 2. When is an operator algebra W the covariance algebra for some covariant system over a given locally compact group G? Introduction. If G is a locally compact group and p: G -Aut(A) is a continuous homomorphism of G into the group of *-automorphisms of an operator algebra A, the triple (A, p, G) is called a covariant system. (A more precise definition is given in Chapters 2 and 3.) This notation was introduced by Doplicher, Kastler and Robinson in 1966, [10], but already Murray and von Neumann considered special cases with A abelian and G discrete in constructing the first non-type I factors. Covariant systems have turned out to be very interesting objects both in theoretical physics and in mathematics. With a representation of (A, p, G) we shall mean a pair (S, U) consisting of a unitary representation U of G and a *-representation S of A with S and U operating over the same Hilbert space such that Spx(a)' UxSaUxI fora&A,xe G. Doplicher, Kastler and Robinson showed that the representation theory of (A, p, G) was essentially the same as that of a certain operator algebra 9l called the covariance algebra of (A, p, G). The representation theory of W has been extensively studied by M. Takesaki in [22], G. Zeller-Meier in [30] and E. G. Effros and F. Hahn in [11] among others, and the covariance algebras provide us with a rich variety of examples of operator algebras. For instance many examples of factors are obtained this way (cf. [20, Chapter 4.2] for some), and A. Connes and M. Takesaki have recently shown that all type III Received by the editors March 13, 1975. AMS (MOS) subject classifications (1970). Primary Primary 46L05, 46L10.
The Thermal Conductivity of Soils

The thermal conductivity of soils of varying moisture content is calculated on a physical basis. The results of this computation are, in a range of moisture contents from 5 to 25 percent, in agreement with experimental data in the literature. The influence of soil composition on conductivity is also explained by the theory. The use for practical purposes of an average resistivity value of 60 to 70 thermal ohms appears justified in the light of this analysis.
On Stellar Streaming Motions in Triaxial Objects: The Case of the Galactic Center

Etude des consequences dynamiques de l'hypothese selon laquelle le gaz situe a r=1,5 kpe, vu en emission HI, incline d'un angle de 22°, est en etat stationnaire, c'est-a-dire qu'il se deplace sur des orbites fermees, stables et qui ne se recoupent pas, inclinees par rapport au disque galactique. On montre que cela implique que le bulbe galactique est triaxial et qu'il tourne dans la direction opposee a celle de la matiere du disque
An Overview of JAXA's Ground-Observation Activities for HAYABUSA Reentry

Abstract On 2010 June 13, the HAYABUSA asteroid explorer returned to Earth and underwent a super-orbital atmo-spheric reentry. In order to recover the sample return capsule and to take ground-based measurements, the JapanAerospace Exploration Agency organized a ground-observationteam and performed optical tracking of the capsule,spectroscopy of the ﬁreball, and measurements of infrasounds and shock waves generated by the ﬁreball. In thisarticle, an overview of the ground-based observation is presented, and an outline of the preliminary results derivedfrom observations is reported. Key words: celestial mechanics: orbit determination — meteors, meteoroids — space vehicles: atmosphericreentry — techniques: acoustic — techniques: spectroscopy 1. Introduction MUSES-C (Mu Space Engineering Satellite C), the world’sﬁrst asteroid explorer, was launched on 2003 May 9, whichwas named “HAYABUSA” afterward. HAYABUSA arrivedat the asteroid ITOKAWA, touched down on it to collectasteroid samples in 2005, and ﬁnally returned to Earth on2010 June 13, changing into arrows of light across the sky.In order to safely recover the sample return capsule (SRC),and to take ground-based scientiﬁc measurements, JapanAerospace Exploration Agency (JAXA) organized a ground-observation team consisting of 16 staff members, as a part
Models of turbulence for aero-optics applications

Turbulence models of density are needed for predicting the performance of airborne optical systems. The existing CFD codes model velocity fluctuations. To avoid rewriting large CFD codes, there is a need for simple yet accurate models, which will be based on the result of standard CFD codes. The applicability of these models to Aero-Optics problems is done by using the relation between the variance of density fluctuation to the optical distortion. The algebraic model that we present here gives good agreement with experimental result for Mach number as high as 9. We also presents models that can be implemented into existing CFD codes by using the result of regular two-equations turbulence models and compare the result to those obtained using CFD results and airborne experiments. We calculated the effects of turbulent fluctuations on optical systems.