Miracle-dz/UniFAR-FTUs huggingface dataset:
Metric calibration of a stereo rig

Describes a method to determine affine and metric calibration for a stereo rig. The method does not involve the use of calibration objects or special motions, but simply a single general motion of the rig with fixed parameters (i.e. camera parameters and relative orientation of the camera pair). The novel aspects of this work are: first, relating the distinguished objects of Euclidean geometry to fixed entities of a Euclidean transformation matrix; second, showing that these fixed entities are accessible from the conjugate Euclidean transformation arising from the projective transformation of the structure under a motion of the fixed stereo rig; and third, a robust and automatic implementation of the method. Results are included of affine and metric calibration and structure recovery using images of real scenes.
Tissue optics, light distribution, and spectroscopy

A model of multilayered tissue is considered. The Monte Carlo simulation technique is used to study laser beam transport through tissues with varying optical properties for each layer (absorption, scattering, scattering anisotropy factor, and refractive index). Calculations are performed for some models of the human skin and adjacent tissues for visible and UV wavelength ranges. New technology for human epidermis optical parameters determination is presented. This technology includes epidermis upper layers glue stripping; in vitro measurements of total transmission, diffuse reflection, and angular scattering of stripping samples; and using an inverse calculation technique based on four-flux approximation of radiation transport theory. The technology was successfully used for depth dependence monitoring of epidermis optical parameters. An inverse Monte Carlo technique for determining the optical properties of tissues based on spectrophotometric measurements is developed. This technique takes into account the 2-D geometry of the experiment, finite sizes of incident beam and integrating sphere ports, boundary conditions, and sideways losses of light.
Axial Buckling and Dynamic Stability of Functionally Graded Microshells Based on the Modified Couple Stress Theory

A nonclassical first-order shear deformation shell model is developed to analyze the axial buckling and dynamic stability of microshells made of functionally graded materials (FGMs). For this purpose, the modified couple stress elasticity theory is implemented into the first-order shear deformation shell theory. Unlike the classical shell theory, the newly developed shell model contains an internal material length scale parameter to capture efficiently the size effect. By using the Hamilton's principle, the higher-order governing equations and boundary conditions are derived. Afterward, the Navier solution is utilized to predict the critical axial buckling loads of simply-supported functionally graded (FG) microshells. Moreover, the governing equations are written in the form of Mathieu–Hill equations and then Bolotin's method is employed to determine the instability regions. A parametric study is conducted to investigate the influences of static load factor, axial wave number, dimensionless length scale parameter, material property gradient index, length-to-radius and length-to-thickness aspect ratios on the axial buckling and dynamic stability responses of FGM microshells. It is revealed that size effect plays an important role in the value of critical axial buckling load and instability region of FGM microshells especially corresponding to those with lower aspect ratios.
Boundary-layer pressures and the Corcos model: a development to incorporate low-wavenumber constraints

This paper re-examines the theoretical arguments that indicate the structure of the pressure field induced on a flat surface by boundary-layer turbulence at low Mach number. The long-wave elements are shown to be dictated by the acoustics of the flow, and the limit of the acoustic range is the coincidence condition of grazing waves where the spectrum is singular and proportional to the logarithm of the flow scale. The surface spectrum is shown to be proportional to the square of frequency at low-enough frequency and to the square of wavenumber at those low wavenumbers with subsonic phase speed. The similarity model successfully used by Corcos for the main convective elements of the field is used in this paper to model the turbulent sources of pressure, not the pressure itself, so that a Corcos-like description of the pressure spectrum is derived that is consistent with constraints imposed by the governing equations. This results in a fairly compact specification of the pressure spectrum with yet-undetermined constants, which must be derived from experiment. Despite an extensive search of published data on the pressure field, it is concluded that existing information is an inadequate basis for setting those constants and that new free field experiments are needed. Boundary layers formed on gliders or buoyant underwater bodies offer the most promising source of such data. The paper concludes with a study of how large flush-mounted transducers discriminate against the local flow noise field and i t is shown that they do so at a rate of 9 decibels per doubling of transducer diameter. This different conclusion from Corcos’ correct 6 decibel rate for small transducers is entirely due to the low- wavenumber constraints on the spectrum, which are misrepresented in the simple similarity model. This result, which conforms with the constraints imposed by the weak compressibility of the fluid, is the same as that later suggested by Corcos for transducers that are large on the boundary-layer scale.
Performance of the electrostatic collection type radon and toron detector

The major background source in the underground experiments, such as a search for the double beta decay, is recognized as the radio-active materials, specifically the daughter nucleus of toron, /sup 208/Tl, in the environment as well as the detector itself. To measure such contamination, a large volume electrostatic collection-type detector having radon sensitivity, or the detection limit, of the order of 10mBq/m/sup 3/ is commonly used. In case, for example, of an experimental configuration utilizing a drift chamber, the measurement of radio-active contamination in the filling gas is crucial. The present detector seems to be useful in the estimate of minute amount of the radon as well as the toron in the gas. To understand such type of the detector, we have studied a general behavior of the 1 l volume detector, inside of which is a PIN photodiode held at a negative potential. The radio-active ions, such as poloniums and bismuth, are collected and their a decays are detected as clearly separated several peaks. Some results are presented in this report for the lifetime measurements of natural radon /sup 222/Rn and toron /sup 212/Pb. Other results also will be presented, such as a relation between the collection efficiency of the daughter nucleus, /sup 218/Po, and the humidity.
Relativistic electron precipitation enhancements near the outer edge of the radiation belt

The authors examined characteristics of relativistic electron precipitation bursts observed by the Heavy Ion Large Telescope (HILT) experiment onboard the Solar, Anomalous, and Magnetospheric Particle Explorer (SAMPEX) satellite. They report on relatively narrow, persistent, latitudinal bands of precipitation with time scales of 10 {approximately} 30 sec near the outer edge of the radiation belt: these develop and decay with a time scale of a few hours. Acceleration processes more effective than the usual radial diffusion process or scattering process would be needed to explain this strong precipitation band phenomenon. Another prominent signature is microbursts with a time scale down to a few hundred milliseconds. It is suggest that these microbursts are due to wave-particle interaction involving a relaxation-oscillator type of mechanism. 18 refs., 5 figs.
Observation of saturated polarization and dielectric anomaly in magnetoelectric BiFeO3 thin films

We report here synthesis of phase-pure magnetoelectric BiFeO3 thin films with controlled oxygen stoichiometry on Pt/TiO2/SiO2/Si substrate using pulsed-laser deposition technique. Saturated ferroelectric hysteresis loop has been observed in phase-pure and highly resistive BiFeO3 thin films. The dielectric response study of the films with temperature indicates an anomaly in dielectric constant e(T), in the vicinity of Neel temperature (∼380 °C). This anomaly in e(T) is explained as an influence of vanishing magnetic ordering on electric ordering of magnetoelectric BiFeO3 sample.
The drag on needles moving in a Langmuir monolayer

The motion of membrane-bound objects is important in many aspects of biology and surface chemistry. Here we derive some general relations for objects moving in a surface film overlying a fluid of depth H. A solution to the problem of the drag can be obtained from a two-dimensional system of integral equations. Here we focus on the problem of an ideal needle moving edge-on (in the direction of its tip) or broadside-on (perpendicular to the direction of the tip). It is shown that in comparison to the drag on a circular disk a new scaling regime of the drag on a needle arises when the ratio between surface shear viscosity and subphase viscosity $\eta_s/\eta$ is smaller than the length of the needle.
Pressure and entropy changes in the flow‐braking region during magnetic field dipolarization

[1] Changes in plasma moments and entropy during dipolarizations are studied using Time History of Events and Macroscale Interactions during Substorms observations made near the neutral sheet at 6–12 RE on the nightside. Plasma tube entropy (pV5/3) at the observation point is estimated for the data set of 147 dipolarizations using the formula of Wolf et al. (2006). Plasma pressure began to increase shortly before dipolarization and proceeded without considerable entropy change until the arrival of the dipolarization front, after which major entropy changes occurred. We have found that on average, postdipolarization plasma pressure changes very little from predipolarization plasma pressure at r = 10–12 RE and increases only slightly in the near-Earth region. Although the associated plasma tube entropy always decreases in the region downtail of r = 8 RE, this decrease becomes smaller closer to the Earth. The local entropy estimate pn−5/3 shows a large increase, however, suggesting ∼40% reduction in flux tube particle content after dipolarization. Our statistical results provide a constraint for dipolarization theories and support the bubble model of dipolarizations.
A prediction of the gamma-ray flux from Nova Herculis 1991

UV observations made with the IUE satellite of Nova Her 1991 are presented and discussed. A distance of 3.4 kpc and reddening of 0.6 E(B-V) to Nova Her 1991 are determined by comparing its UV and optical outburst behavior with those of the extragalactic ONeMg nova LMC 1990 No. 1. Her 1991 was also detected by Rosat five days into its outburst, and it is argued that a small fraction of the X-rays may be the product of Comptonized 1.2 and 0.5 MeV emission from the decay of Na-22. If the mass of ejected shell is indeed as high as was estimated by Woodward et al. (1992), namely 0.0001 solar mass, then the present results predicted that Na-22 gamma-ray emission from the ejecta of Nova Her 1991 would still be detectable by GRO in the spring of 1992. The detection level was expected to be about 5 sigma in a two-week observation. Such a detection would strongly guide and constrain the hydrodynamic and nucleosynthesis simulations of nova outbursts on massive white dwarfs. 23 refs.
Optimization shows Halbach arrays to be non-ideal for induction devices

Among the advantages of Halbach magnet arrays is the fact that the magnetic field behind the array is very small, and the magnets act as a natural flux guide. This paper discusses an optimization index that proves useful for objectively examining any magnet array used in induction applications. Multivariate spline tensor analysis and variable metric methods with a boundary element solver are used to predict the index of performance for these arrays and competing alternatives. The results show that steel based magnet arrays will out-perform conventional Halbach arrays.
Reducing Bias in CAT Trait Estimation: A Comparison of Approaches

The use of a beta prior in trait estimation was extended to the maximum expected a posteriori (MAP) method of Bayesian estimation. This new method, called essentially unbiased MAP (EU-MAP), was compared with MAP (using a standard normal prior), essentially unbiased expected a posteriori, weighted likelihood, and maximum likelihood estimation methods. Comparisons were made based on the effects that the shape of prior distributions, different item bank characteristics, and practical constraints had on bias, standard error, and root-mean-square error (RMSE). Overall, EU-MAP performed best. This new method significantly reduced bias in fixed-length tests (though with a slight increase in RMSE) and performed reasonably well when a fixed posterior variance termination rule was used. Practical constraints had little effect on the bias of this method.
Constraints on nonstandard -s in expletive there sentences: a generative–variationist perspective

This article examines grammatical conditioning of the use of nonstandard -s in expletive there sentences. The discussion is based on data from a Midlands variety of English (UK). In negative constructions, speakers tend to allow for nonstandard -s with no and constituent not, but not to use it with n't or clausal not. Further, nonstandard -s is admitted in declarative existentials, but disfavoured in interrogatives. By comparison, occurrences of nonstandard -s in nonexistential structures did not seem to demonstrate these constraints. Investigating such constraints is instructive in several respects. First, they help to identify the nature of nonstandard -s. Second, they provide new evidence for the generative inquiry into issues relating to subject–verb agreement. Third, they delimit variable contexts for variationist analyses. In this way generative and variationist objectives meet. I will argue that researching syntactic variation necessitates combining generative and variationist methodology.
Coupled displacive and order–disorder dynamics in LiNbO3 by molecular-dynamics simulation

We demonstrate that molecular-dynamics simulations can reproduce the ferroelectric behavior of LiNbO3 and the ferroelectric–paraelectric phase transition. We find that this phase transition is a two-stage process involving a displacive transition in the Nb–O cages at a temperature below the Curie temperature and an order–disorder transition in the Li–O planes at the Curie temperature itself.
Vibration modes of the violin forced via the bridge and action of the soundpost

The action of the soundpost in a violin is not well understood and fundamental knowledge is needed. Therefore low‐frequency forced modes, operating deflection shapes, 250–600 Hz of a violin were investigated. Harmonic, sine wave, excitation was applied via the bridge (resembling playing) or via the sound from a loudspeaker. The latter excitation gives a reciprocal measure of radiativity. The modes were investigated with TV‐holography and electro‐acoustical admittance measurements. A carefully selected violin was investigated without soundpost, with soundpost, and with the soundpost position shifted toward the centerline. Answers were sought to three questions: Which are the violin modes forced via the bridge? To what extent do they radiate sound? What is the action of the soundpost? The observed modes were mostly not pure normal modes but mode combinations. Generally there is a nodal line close to the soundpost position of the plates. Schelleng has hypothesized that the main action of the soundpost is to .
Generalized expressions for the calculation of elastic constants by computer simulation

The general expressions, valid for any potential, for the calculation of elastic constants through computer simulation are given. At zero temperature, the elastic constants are found to be the sum of a generalization of the Born term and a term accounting for internal relaxations that arise when a system with more than one atom in the primitive unit cell is strained. The fluctuation formulae used in finite temperature simulations are found to be straightforward generalizations of those used for pair potentials. The connection between the finite‐temperature and zero‐temperature methods is also made.
Thermal expansion of single-walled carbon nanotube (SWNT) bundles: X-ray diffraction studies

Thermal expansion coefficient in single-walled carbon nanotube bundles was determined as $(\ensuremath{-}0.15\ifmmode\pm\else\textpm\fi{}0.20)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5} (1/\mathrm{K})$ for the tube diameter and $(0.75\ifmmode\pm\else\textpm\fi{}0.25)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5} (1/\mathrm{K})$ for the triangular lattice constant by means of x-ray scattering between 300 K to 950 K. The value for the intertube gap was $(4.2\ifmmode\pm\else\textpm\fi{}1.4)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5} (1/\mathrm{K}),$ which is larger than $2.6\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5} (1/\mathrm{K})$ for the c-axis thermal expansion in graphite. The results reveal the presence of a remarkably larger lattice anharmonicity in nanotube bundles than that of graphite. The small value for the tube diameter is consistent with the seamless tube structure formed by a strong covalent bond between carbon atoms comparable to that in graphite.
On the transmission performances and the chirp parameter of a multiple-quantum-well electroabsorption modulator

The chirp parameter of a multiple-quantum-well (MQW) electroabsorption modulator was measured with accuracy for several operating wavelengths in the 1.5 /spl mu/m window. It varied strongly with applied bias. Effective chirp parameter, defined as the ratio of phase change to transmission change between modulator on and off states, is about zero, or even negative. However, experimental transmission length on standard fiber at 10 Gb/s NRZ is much smaller than what is expected for such a low chirp parameter. It is demonstrated that the effective chirp parameter should not be computed from changes between on and off states, but from the average of the chirp parameter values in a 3 dB region of the most transparent states of the modulator. This simple rule allows us to predict transmission performances based on measurements of the chirp parameter, and can be used to optimize optical components without actually experimenting on a transmission system. The effective chirp parameter of the MQW electroabsorption modulator is found positive. This should be intrinsic to red-shift electroabsorption effects, such as the quantum confined Stark effect. >
Effect of bias voltage and interdiffusion in Ir-Mn exchange-biased double tunnel junctions

Dual-spin-valve-type double tunnel junctions (DTJs) of sputtered Ir-Mn/Co-Fe/AlO/sub x//Co/sub 90/Fe/sub 10//AlO/sub x//Co-Fe/Ir-Mn having the R(resistance)/spl times/A(area) product; RAP /spl sim/3.0 k/spl Omega/-/spl mu/m/sup 2/ were fabricated and annealed at various temperatures (150-400/spl deg/C) to introduce interdiffusion. There is a relation between the loss of the magnetoresistance (MR) ratio and that of DC bias voltage value at which the MR ratio decreases in half value (V/sub 1/2/). After annealing at 300/spl deg/C, both the MR ratio and V/sub 1/2/ were increased to 42.4% and 872 mV, respectively, with increasing annealing temperature. Annealing above 300-350/spl deg/C, both MR ratio and V/sub 1/2/ decreased rapidly. The loss of the MR ratio and that of V/sub 1/2/ are well explained by considering interdiffusion of O and Mn at the AlO/sub x//Co-Fe/Ir-Mn interfaces. The mechanism for the loss of MR ratio is not only related to the loss of interface polarization, but is also related to the barrier properties, taking into account the spin-independent two-steps tunneling via defect states in the barrier. These results are consistent with the X-ray photoelectron spectroscopy and cross-sectional transmission electron spectroscopy measurements, which indicate the existence of an Al-Mn-O barrier above 300/spl deg/C.
Free generators in free inverse semigroups

Using the characterization of the free inverse semigroup F on a set X, given by Scheiblich, a necessary and sufficient condition is found for a subset K of an inverse semigroup S to be a set of free generators for the inverse sub semigroup of S generated by K. It is then shown that any non-idempotent element of F generates the free inverse semigroup on one generator and that if |X| > 2 then F contains the free inverse semigroup on a countable number of generators. In addition, it is shown that if |X| = 1 then F does not contain the free inverse semigroup on two generators.
Mixture Representation of the Maximum Entropy Density Through Archimedean Copulas

In this article, we obtain a mixture representation of the maximum entropy density introduced by Rodrigues (2004) via Laplace approximation. This representation suggests, as in Sklar (1959), a dependence structure through Archimedean copulas independently of the specified marginal distributions. This result can be used as a natural Bayesian and non Bayesian procedure to estimate the dependence function and the marginal, separately.
TESTING THE 1995 BINARY BLACK HOLE MODEL OF OJ287

In 1995, a binary black hole model was proposed for the quasar OJ287, where the smaller secondary black hole impacts the accretion disk of the primary black hole twice during its 12 yr orbit and causes a double peak of optical outbursts. The model predicted four major outbursts and one minor outburst during the period 1996–2010. All five have now been observed. In this paper, we ask how accurate the predictions were. We use the latest optical observations from Tuorla Observatory and the KVA telescope at La Palma together with previously published data to construct a light curve for this period. We average the data in 0.04 yr bins, and subtract the observed flux from the 1995 model flux at each bin. We find that the residuals are small: they are well described by random noise of amplitude 1.4 mJy. This level is small compared with the amplitudes of the major outbursts, 5–7 mJy. Ignoring the noise, the binary model explains the optical data remarkably well.
Multifrequency observations of the double-nucleus galaxy Markarian 266 - Enhanced synchrotron emission induced by a merger

Presentation d'observations CCD optiques et radio a synthese d'ouverture de la galaxie a noyau double Mkn 266 (NGC 5256). Cette radiogalaxie est en fait constituee de 3 sources continuum non thermique. On suppose que l'emission synchrotron est stimulee par la collision de deux galaxies dont les disques entrent en coalescence
Scattering of an obliquely incident wave by a multilayered elliptical lossy dielectric cylinder

The scattering problem of obliquely incident waves on a multilayered elliptical cylinder is considered. The cylinder is assumed homogeneous and isotropic but lossy. Both polarization of the incident wave, the E wave, and the H wave are considered. In the theoretical analysis the number of layers are unlimited, but in the numerical analysis we limit the number of layers so we can avoid excessively long computer running time. The numerical results include the bistatic radar cross sections, the specular differential cross sections, and the efficiency factors for absorption, scattering, and extinction. The computed results show the dependence of the scattering on the size, shape, material, and the angle of the incident.