Miracle-dz/UniFAR-FTUs huggingface dataset:
A moving pseudo‐boundary method of fundamental solutions for void detection

We propose a new moving pseudo‐boundary method of fundamental solutions (MFS) for the determination of the boundary of a void. This problem can be modeled as an inverse boundary value problem for harmonic functions. The algorithm for imaging the interior of the medium also makes use of radial polar parametrization of the unknown void shape in two dimensions. The center of this radial polar parametrization is considered to be unknown. We also include the contraction and dilation factors to be part of the unknowns in the resulting nonlinear least‐squares problem. This approach addresses the major problem of locating the pseudo‐boundary in the MFS in a natural way, because the inverse problem in question is nonlinear anyway. The feasibility of this new method is illustrated by several numerical examples. © 2012 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2013
Theory and arrangements of self-calibrating whole-body 3-D-measurement systems using fringe projection technique

We report the basic concepts and experimental arrange- ments of self-calibrating 3-D measurement systems using structured- light illumination (fringe projection), which ensure a high number of ob- ject points, rapid data acquisition, and a simultaneous determination of coordinates and system parameters (self-calibration), making the system completely insensitive to environmental changes. Furthermore, it is un- necessary to have any marker on the object surface and a subsequent matching of the single views is not required to obtain a full-body mea- surement. For this purpose, the test object is successively illuminated with two grating sequences perpendicular to each other from at least two different directions, resulting in surplus phase values for each measure- ment point. Based on these phase values one can calculate the orienta- tion parameters as well as the 3-D coordinates simultaneously. Different measurement setups that have the ability to measure the entire surface (full-body measurement) are reported. Results are presented showing the power of this concept, for example, by measuring of the complete 3-D shape of specular technical surfaces, whereas the object volumes can differ strongly. Theoretical estimations proven by first measurements show a coordinate measurement accuracy of up to 10 25 of the measure- ment field size. © 2000 Society of Photo-Optical Instrumentation Engineers. (S0091-3286(00)01801-8)
A model of an X-ray-illuminated accretion disk and corona

The X-ray-illuminated surface of the accretion disk in a low-mass X-ray Binary (LMXRB) and the X-ray-heated corona above the disk produce optical, UV, and soft X-ray emission lines. This paper presents 1D models of the emission line spectra and the vertical temperature and density structures at different radii. The models include a detailed treatment of the important atomic processes and an escape probability treatment of radiative transfer. Soker and Raymond (1993) use the density structure predicted by these models for a 2D Monte Carlo simulation of the photon scattering in the accretion disk corona (ADC) to examine the effects of the ADC on the angular distribution of X-rays and the flux of X-rays incident on the outer disk. This paper concentrates on the emission line fluxes for various elemental abundances and disk parameters. The UV lines of the classic LMXRBs are consistent with the model predictions. Some CNO processing is necessary to account for the nitrogen and helium abundances in Sco X-1 and other LMXRBs. Comparison of the models with observed spectra also points to a soft X-ray component with luminosity comparable to the hard X-rays. The models predict a substantial luminosity in the group of highly ionized iron lines near 100 A.
Detection of coronary artery tree using morphological operator

Presents a technique of the automatic detection of the coronary artery tree on the coronary cineangiogram. The method uses several kinds of morphological operations. The morphological Top-Hat operator is used for enhancing the shape of the artery. The morphological erosion and the half-thresholding are used for removing points except the coronary area. Then one can extract the entire coronary artery tree on the angiogram after pointing at just one point on the coronary artery. The extracted coronary parts are skeletonized by the thinning operation. Finally the morphological watershed transformation is done by using the skeleton and the dilated binary image of the coronary. As a result, a clear boundary of the coronary artery is obtainable automatically. Some experimental studies confirm the ease and correctness of the detection of the coronary artery boundary by the method proposed.
Estimation of Asymmetric Stochastic Volatility Models: Application to Daily Average Prices of Energy Products

Energy supply and demand, and as a consequence energy prices, are likely to represent one of the biggest challenges of the 21st century. Commodity markets exhibit increased volatility when there is little or no underutilized supply capability to meet natural fluctuations in demand. In the case of energy markets, the large capital requirements and significant lead times associated with energy production and delivery make them more susceptible to the imbalances in supply capability and demand. Energy price volatility has destructive impact on market agents, and this impact is intensified when the prices exhibit asymmetric volatility. This article pursues two aspects of the issue. First we consider general aspects, especially the asymmetric pattern of volatility of daily returns of different types of energy products. Then, we analyze the behaviour of daily returns by using traditional models of volatility that include AGARCH, TGARCH, EGARCH, and ARSV strategies, as well as a threshold asymmetric autoregressive stochastic volatility (TA‐ARSV) model that we propose. The energy products considered in this analysis are probably the most relevant energy products for the economic activity of the nations and the economic relations between countries: Crude Oil (OPEC reference basket and London Brent index), Gasoline, Natural Gas, Butane, and Propane. We use spot prices and the time reference ranges from 1986–1993 to 2009 depending on the product.
Reduction methods of fuzzy inference rules with neural network learning algorithm

Describes reduction methods of the rule unit with fuzzy neural networks. The approaches are presented with a reducing mechanism of the rule unit which use three parameters, central value, width of the membership function in the antecedent part, and real number in the consequent part, constituted according to a fuzzy neural system. These methods indicate that a different technique exists besides the reduction approach. Experimental results are presented in order to show that the effectiveness is different in the proposed techniques for average inference error and learning iteration.
On-line measurements of proton beam current from a PET cyclotron using a thin aluminum foil

The number of cyclotrons capable of accelerating protons to about 20 MeV is increasing throughout the world. Originally aiming at the production of positron emission tomography (PET) radionuclides, some of these facilities are equipped with several beam lines suitable for scientific research. Radiobiology, radiophysiology, and other dosimetric studies can be performed using these beam lines. In this work, we measured the Bragg peak of the protons from a PET cyclotron using a stacked target consisting of several aluminum foils interleaved with polyethylene sheets, readout by in-house made transimpedance electronics. The measured Bragg peak is consistent with simulations performed using the SRIM/TRIM simulation toolkit. Furthermore, we report on experimental results aiming at measuring proton beam currents down to 10 pA using a thin aluminum foil (20-μm-thick). The aluminum was chosen for this task because it is radiation hard, it has low density and low radiation activity, and finally because it is easily available at negligible cost. This method allows for calculating the dose delivered to a target during an irradiation with high efficiency, and with minimal proton energy loss and scattering.
Teaching Square Roots: Conceptual Complexity in Mathematics Language.

Mathematics is an 'artificial' deliberately constructed language. In teaching mathematics we surround the focal formal content language which is mathematics, with other informal instructional language. For English speakers, many mathematical words are taken directly from everyday English, fitted with specialised meanings, and used, from then on, with special mathematical significance. The example of teaching the concept of 'square root' is discussed.
On‐line robust parameter identification for parabolic systems

In this paper a robust scheme for the adaptive parameter identification of parabolic distributed parameter systems is developed. Results from the finite‐dimensional treatment of the parameter projection method and σ (sigma) modifications to the standard adaptation rules are extended to infinite‐dimensional systems. For the class of systems under study, modifications to these standard parameter adaptation rules were deemed necessary in order to account for the additional mathematical subtleties that arise when dealing with infinite‐dimensional systems. Copyright © 2001 John Wiley & Sons, Ltd.
Multifractal characterization of water-worked gravel surfaces

This study investigates the roughness of water-worked gravel surfaces using stable gravel-beds armoured in flume and field experiments. As an alternative to traditional approaches, multifractal analysis is employed to investigate the roughness of these surfaces. Power spectra analysis is used to study scale-invariant regimes, defined by the ranges of scales where the spectra follow power laws. Then, multifractal spectra are calculated and analysed. The strength of multifractality reflecting heterogeneity of elevations is related to the development of a stable armour layer. The development of armouring processes of the gravel surfaces formed in the flume experiments is investigated using the effective grain size approach based on Gessler's model. For surfaces in the field, the two-dimensional second-order structure function is used to study the static armour surfaces due to the absence of historical hydrological data. The results of these analyses confirm the results of multifractal analyses.
Surface processes of dust particles in low pressure plasmas

This paper presents several aspects of applied dusty plasma research. New applications of dust particles are emerging; there is growing demand for particles with special properties, and for particle-seeded composite materials. Low-pressure plasmas offer a unique possibility of confinement, control and fine tailoring of particle properties. The role of low-pressure technology in surface modification (coating) of dust grains is discussed and illustrated with examples. Fundamental research related to industrial particle treatment aims at the understanding the surface chemistry of processing. More specifically, the nature of plasma-particle interactions must be resolved. Heat exchange and particle temperature, discussed in this paper, are of major interest in the applied dusty plasma studies.
Direct evidence of micropipe-related pure superscrew dislocations in SiC

A set of powerful x-ray imaging techniques using white-beam synchrotron radiation have been developed and applied to clearly reveal and map micropipes in SiC crystals at a “magnified” level. The experimental results and the corresponding simulations demonstrate explicitly that the micropipes are pure superscrew dislocations (SSDs). Moreover, these techniques provide accurate descriptions of the detailed structure of the SSDs, including the spatial distribution of the strain fields, the magnitudes of the Burgers vectors, the dislocation senses, and the surface relaxation effects.
Ferromagnetic resonance study of GdN thin films with bulk and extended lattice constants

The magnetic properties of GdN thin films with bulk and 2.4% extended lattice parameters have been studied by x-band ferromagnetic resonance (FMR) spectroscopy. Simple, anisotropic, single line FMR spectra are observed in the 0 to 18 kOe field range. Both films show an in-plane easy axis of magnetization due to the predominance of the shape related demagnetization fields. The films deposited on (100) Si substrates are strained with uniaxial anisotropy constants up to K-u=+5x10(6) erg/cm(3) at T=4 K. The lattice extension reduces the magnetization and decreases the Curie temperature from 69 K for the bulk films to 20 K for the films with extended lattice constants. Highly increased FMR linewidths are observed for the lattice extended films indicating large, local variations of the demagnetization fields.
Effects of spectral smearing on the intelligibility of sentences in noise

Cochlear hearing loss is generally associated with a variety of deficits in the ability to analyze sounds, including reduced frequency selectivity. The complex interrelationships between the different deficits have made it difficult to assess the contribution of reduced frequency selectivity to the difficulties experienced by hearing‐impaired people in understanding speech. To address this question, the effects of reduced frequency selectivity on the place representation of speech stimuli in the auditory system were simulated by ‘‘smearing’’ the spectra of the stimuli, using the overlap–add method. The smearing was designed to evoke excitation patterns in a normal ear that would resemble those evoked in an impaired ear using unsmeared stimuli. Several different types of smearing were used, simulating specific degrees of broadening and asymmetry of the auditory filter. Sentences in quiet and in speech‐shaped noise were smeared and presented to normally hearing listeners in intelligibility tests. The result.
Evaluation of soft possibilistic classifications with non-specificity uncertainty measures

The aim of this paper was to investigate the usefulness of non-specificity uncertainty measures to evaluate soft classifications of remote sensing images. In particular, we analysed whether these measures could be used to identify the difficulties found by the classifier and to estimate the classification accuracy. Two non-specificity uncertainty measures were considered, the non-specificity measure (NSp) and the U-uncertainty measure, and their behaviour was analysed to evaluate which is the most appropriate for this application. To overcome the fact that these two measures have different ranges, a normalized version (Un) of the U-uncertainty measure was used. Both measures were applied to evaluate the uncertainty of a soft classification of a very high spatial resolution multispectral satellite image, performed with an object-oriented image analysis based on a fuzzy classification. The classification accuracy was evaluated using an error matrix and the user's and producer's accuracies were computed. Two uncertainty indexes are proposed for each measure, and the correlation between the information given by them and the user's and producer's accuracies was determined to assess the relationship and compatibility of both sources of information. The results show that there is a positive correlation between the information given by the uncertainty and accuracy indexes, but mainly between the uncertainty indexes and the user's accuracy, where the correlation achieved 77%. This study shows that uncertainty indexes may be used, along with the possibility distributions, as indicators of the classification performance, and may therefore be very useful tools.
Multimode spherical hydrophone

An investigation is made of the multimode spherical hydrophone. The physical model considered in the present analysis is a piezoelectric ceramic spherical shell whose surface is sectionally electroded, with each section considered an electrically separated hydrophone. The induced voltage due to the incident acoustic wave is obtained for a radially poled ceramic shell. The maximum hydrophone sensitivities are calculated for both omnidirectional and dipole modes based on the present model, and the theoretical results are compared with the experimental results. The use of the multimode spherical hydrophone is found to be advantageous over the multimode cylindrical hydrophone in that (1) the resonant frequency of the omnidirectional mode of the spherical model is substantially higher in comparison with that of the cylindrical model for the same mean diameter, and (2) the sphere has identical dipole mode patterns in both directions of azimuth and elevation, whereas the cylinder has different dipole mode patter.
Antihyperlipidemic Property of a Dietary Supplement of Moringa Oleifera Leaves and Pleurotus Ostreatus in Wistar Rats Stressed by Combination of Ethanol-Paracetamol

- High amounts of triglycerides and cholesterol in the blood result in the metabolic condition known as hyperlipidemia. There is currently no specific therapy to reduce the effects of this disorder. In underdeveloped nations, metabolic diseases are treated using Moringa oleifera and Pleurotus ostreatus . Both the nutritional and therapeutic benefits of these two plants are frequently utilized. Purpose: This study aimsto investigate the antihyperlipidemic property of dietary supplement of Moringa oleifera leaves and Pleurotus ostreatus in wistar rats. Materials and methods: A variety of mushroom species were produced in the Mushroom Biotechnology Laboratory
Shortest paths on uncertain terrains

In this dissertation, we introduce the concept of uncertain terrains first suggested by Jörg Sack. We then examine the problem of finding the shortest path that stays on these terrains given certain assumptions about the terrains. We show that this problem is NP-hard under two fairly natural assumptions (meaning that we do not expect any polynomial time algorithm that finds these paths to be discovered).
Light emission from scanning tunnelling microscope on polycrystalline Au films—what is happening at the single-grain level?

When operated with a metallic tip and sample the scanning tunnelling microscope constitutes a nanoscale, plasmonic light source yielding broadband emission up to a photon energy determined by the applied bias. The emission is due to tunnelling electron excitation and subsequent radiative decay of localized plasmon modes, which can be on the lateral scale of a single metal grain (∼25 nm) or less. For a Au-tip/Au-polycrystalline sample under ambient conditions it is found that the intensity and spectral content of the emitted light are not dependent on the lateral grain dimension, but are predominantly determined by the tip geometry. However, the intensity increases strongly with increasing film thickness (grain depth) up to 20–25 nm or approximately the skin depth of the Au film. Photon maps can show less emissive grains and two classes of this occurrence are distinguished. The first is geometrical in origin—a double-tip structure in this case—while the second is due to a contamination-induced lowering of the local work function that causes the tunnel gap to increase. It is suggested that differences in work-function lowering between grains presenting different crystalline facets, combined with an exponential decay in emitted light intensity with tip–sample distance, leads to grain contrast. These results are relevant to tip-enhanced Raman scattering and the fabrication of micro/nano-scale planar, light-emitting tunnel devices.
Ultrafast photoinduced magnetic moment in a charge-orbital-ordered antiferromagnetic Nd 0.5 Sr 0.5 MnO 3 thin film

The effect of photoexcitation in the charge sector on the magnetization has been studied with subpicosecond optical pump-and-probe measurements in an antiferromagnetic manganite. Magneto-optic Kerr measurements show a steplike increase of magnetic moment followed by a gradual growth. The steplike behavior is ascribed to the spin flip scattering in the excited states while the slower process to the spin-lattice thermalization, which exhibits slowing down toward the antiferromagnetic-ferromagnetic transition temperature. The time scale of these processes is much faster compared to the photoinduced demagnetization time of ferromagnetic manganites and reflects the effect of underlying spin-charge-orbital order.
A multivariate extension of a vector of two-parameter Poisson–Dirichlet processes

In the big data era there is a growing need to model the main features of large and non-trivial data sets. This paper proposes a Bayesian nonparametric prior for modelling situations where data are divided into different units with different densities, allowing information pooling across the groups. Leisen and Lijoi [(2011), ‘Vectors of Poisson–Dirichlet processes’, J. Multivariate Anal. , 102, 482–495] introduced a bivariate vector of random probability measures with Poisson–Dirichlet marginals where the dependence is induced through a Lévy's Copula. In this paper the same approach is used for generalising such a vector to the multivariate setting. A first important contribution is the derivation of the Laplace functional transform which is non-trivial in the multivariate setting. The Laplace transform is the basis to derive the exchangeable partition probability function (EPPF) and, as a second contribution, we provide an expression of the EPPF for the multivariate setting. Finally, a novel Markov Chain Monte Carlo algorithm for evaluating the EPPF is introduced and tested. In particular, numerical illustrations of the clustering behaviour of the new prior are provided.
On Classical Solution in Finite Time of BGK-Poisson’s Equations

BGK model is a collision operator for the evolution of gases which satisfies several fundamental properties. Different collision operators for gas evolutions have been introduced earlier, but none of them could satisfy all the basic physical properties: conservation, positivity, correct exchange coefficients, and entropy inequality. However, contrary to Boltzmann model which has a quadratic form, the BGK model presents a heavy nonlinearity which explains the complexity of this analysis.The existence of solution to the periodic Boltzmann BGK model (Bhatnagar–Gross–Krook) coupled with Poisson’s equation has been proved by the same author (see Ben Rejeb (Int J Appl Math 39:4, 2009)). In this paper we are interested to the uniqueness of such solution.
Capillary Effects in Immiscible Flows in Heterogeneous Porous Media

Capillary effects can be important in immiscible flow in heterogeneous media, particularly at low capillary numbers. Experiments are performed to study steady-state saturation profiles during drainage in 3D porous media with sharp changes in permeability. It is found that the saturation response is closely linked to the permeability variation. The results are in good agreement with numerical simulations based on a macroscopic description.
Defect generation in 3.5 nm silicon dioxide films

The generation of defects in thin 3.5 nm SiO2 films has been measured as a function of the average electron energy and total injected fluence. It is found that the generation of defects during electron injection for both positive and negative bias manifests itself as positive charge as measured from the increase in the current for a given bias. Positive charge generation is seen for electrons injected into the silicon dioxide conduction band, with the generation rate increasing with increasing electron energy. Electrons that traverse the oxide film via direct quantum‐mechanical tunneling do not generate measurable defects. These results are consistent with previously published results on thicker films where the defects were attributed to positive charge found near the anode.