Miracle-dz/UniFAR-FTUs huggingface dataset:
Relative moment tensor inversion based on ray theory: theory and synthetic tests

SUMMARY A relative moment tensor inversion is developed for seismic sources belonging to a small source region. The impulsive point-source approximation is assumed to be valid. Input data are amplitudes of low-pass filtered, isolated body-wave phases in the seismograms, and the azimuths and take-off angles of the corresponding rays at the sources. The new aspect of the method is the elimination of Green's functions from the equations. Hence only a minimum of structural information is needed, sufficient to identify correctly phases Pg, PmP, Sg etc. and to determine azimuths and take-off angles. The relative method without reference mechanism is applicable to clusters of seismic sources with different radiation patterns. For source clusters with identical radiation patterns a reference mechanism must be known. The relative method without reference mechanism is studied with synthetic data with regard to additive, Gaussian noise, poor azimuthal station coverage and the resolution of non-double-couple components.
Eclipse studies of the dwarf nova HT Cassiopeiae. I, Observations and system parameters

Optical eclipses are used to investigate the structure of the dwarf nova HT Cas. We present high-speed multicolor light curves covering four eclipses at UBR in 1982 September and 12 eclipses at UBVR in 1983 November-December. From the latter we derive high-quality mean light curves that cleanly separate the white dwarf and accretion disk eclipses. The bright spot is weak or absent during our observations, but a 0.3 mag orbital modulation, centered on mid-eclipse, is seen in the U-band. We define a purely photometric model of the system using contact timings of the white dwarf from the data presented here and measurements of the bright spot eclipses in other data (published by Patterson in 1981).
Optical spectroscopy of X-ray-selected active galactic nuclei

Optical spectra of 65 X-ray-selected AGN (XAGN) from several identification samples are presented and classified based on their spectra and optical-continuum luminosities. The red XAGN of Stocke et al. (1983) appear to be a mix of previously known types of objects; their red colors appear to be caused by starlight. X-ray selection may be an efficient way to find narrow-line Seyfert 1 galaxies. A possible spectral discriminant between quasars and Seyfert 1 galaxies is pointed out. 50 references.
Metodi per l’interpolazione delle precipitazioni e delle temperature mensili della Basilicata

Abstract: Spatial interpolated climatic data on grids are important as input in forest modeling because climate spatial variability has a direct effect on productivity and forest growth. Maps of climatic variables can be obtained by different interpolation methods depending on data quality (number of station, spatial distribution, missed data etc.) and topographic and climatic features of study area. In this paper four methods are compared to interpolate monthly rainfall at regional scale: 1) inverse distance weighting (IDW); 2) regularized spline with tension (RST); 3) ordinary kriging (OK); 4) universal kriging (UK). Besides, an approach to generate monthly surfaces of temperatures over regions of complex terrain and with limited number of stations is presented. Daily data were gathered from 1976 to 2006 period and then gaps in the time series were filled in order to obtain monthly mean temperatures and cumulative precipitation. Basic statistics of monthly dataset and analysis of relationship of temperature and precipitation to elevation were performed. A linear relationship was found between temperature and altitude, while no relationship was found between rainfall and elevation. Precipitations were then interpolated without taking into account elevation. Based on root mean squared error for each month the best method was ranked. Results showed that universal kriging (UK) is the best method in spatial interpolation of rainfall in study area. Then cross validation was used to compare prediction performance of tree different variogram model (circular, spherical, exponential) using UK algorithm in order to produce final maps of monthly precipitations. Before interpolating temperatures were referred to see level using the calculated lapse rate and a digital elevation model (DEM). The result of interpolation with RST was then set to originally elevation with an inverse procedure. To evaluate the quality of interpolated surfaces a comparison between interpolated and measured temperatures at eight sites from an independent dataset was done. There was a good agreement with mean R2=0.99 (mean RMSE=0.6°C). Based on this results universal kriging estimates and RST were used to produce monthly rainfall and temperature maps for Basilicata region aimed at using as quality input in forest modeling.
Measurement of mechanical properties for MEMS materials

The microscopic mechanical devices in microelectromechanical systems (MEMS) use materials such as silicon and many other thin films, which had not previously been considered mechanical materials and thus are not well characterized regarding their mechanical properties. However, as the field matures, sustained research and commercial development in the coming years will demand better understanding of mechanical properties such as Young's modulus and the fracture strength. Uniaxial tension testing is generally considered the most reliable way to measure the mechanical properties. However, the problems associated with the microscopic size of the test specimen for MEMS, such as sample handling and sample alignment, led to such alternative ways as membrane-bulge testing and natural frequency testing at the beginning of MEMS. In this paper, recent methods for testing microscale mechanical properties and their results are summarized. Many reports, based on two distinct types of test, beam bending and direct tension, are introduced. The efforts to integrate the sample and loading system on the microscopic scale are also explained. Studies of fatigue, the most recent development in microscale measurement of mechanical properties, are discussed. The results from the testing methods described are listed for comparison.
Local Dielectric Property of Cubic, Tetragonal, and Monoclinic Hafnium Oxides

We investigate the electronic contribution to local dielectric property in terms of the local polarizability density and dielectric constant density, for the cubic, tetragonal, and monoclinic structure of HfO2 and compare their dielectric properties with those of SiO2. We show appropriate termination conditions of our cluster models to realize the condensed property of dielectric; point charge conditions for HfO2 whose bond is ionic, while hydrogen termination conditions for SiO2 whose bond has covalent property. We show that local parts of materials have complicated responses to external electric fields, in particular, rotational ones. Hence, nanosize materials should be studied in the local and tensor quantity analysis to describe rotational responses correctly. It is clarified that the electronic contribution to local polarizability and dielectric constant densities is almost independent of the structures of HfO2 crystals. We show that the electronic contribution to dielectric response of HfO2 is significantly large compared to those of SiO2. In addition, it is found that the average value of dielectric constant around O atoms is larger than other regions in both HfO2 and SiO2.
Disturbance attenuation using proportional integral observers

In this paper, we first propose a proportional integral observer design for single-output uncertain linear systems which permit us to attenuate either measurement noise or modelling errors. We show that, when only sensor noise is present in the system, an integral observer alone suffices to achieve good convergence and filtering properties. On the other hand, when modelling errors and sensor noise are present, we show that, for some classes of linear systems, the proportional integral observer allows us to decouple completely the modelling uncertainties while keeping satisfactory convergence properties. A comparison of the classical proportional observer to the proposed observers are given via academic simulation examples. We next extend the design to the class of single-output uniformly observable non-linear systems. We show through a practical simulation example, dealing with a flexible joint robot, that the non-linear proportional integral has very satisfactory disturbance attenuating properties.
Stochastic nonrelativistic approach to gravity as originating from vacuum zero-point field van der Waals forces

We analyze the proposal that gravity may originate from a van der Waals type of residual force between particles due to the vacuum electromagnetic zero-point field. Starting from the Casimir-Polder integral, we show that the proposed approach can be analyzed directly, without recourse to approximations previously made. We conclude that this approach to Newtonian gravity does not work, at least not with this particular starting point. Only by imposing different or additional physical constraints, or by treating the underlying dynamics differently than what are embodied in the inherently subrelativistic Casimir-Polder integral, can one expect to escape this conclusion.
Hydrogen peroxide production by ion irradiation of thin water ice films

In this paper we present the results of new experiments on ion irradiation of water ice performed on thin films to study the synthesis of the hydrogen peroxide molecule and discuss the possibility of detecting it in icy mantles on interstellar grains. The used experimental technique has been in situ infrared spectroscopy. We have irradiated thin films (i.e. the ice thickness was smaller than the penetration depth of the used ion) with three different ions, namely 200 keV of H + and He + and 400 keV of Ar ++ . The experiments were carried out at temperatures of 16 and 77 K. We have found that hydrogen peroxide is produced by all of the different ions at both temperatures. The detection of such a molecule has been possible from the study of its infrared feature centered at about 2850 cm −1 (3.5 µm). The obtained results also show that the produced H2O2/H2O(%) ratio is greater for the heaviest ion (∼6% for the case of Ar ++ )a nd that H + is the ion that produces the smallest quantity (∼1%). These upper limits in the production of hydrogen peroxide constrain the quantity of H2O2 that can be formed after bombardment by cosmic particles on icy mantles of grains in the interstellar medium.
Greek bilingual listeners perceive the tritone stimuli differently from speakers of English

When listeners are presented with pairs of octave‐complex tones related by a tritone interval (a half‐octave), they hear the pattern as ascending or descending, according to an individual pitch class template. Deutsch (1991) has claimed that this template may be influenced by language. In order to test this hypothesis, data from Greek bilingual listeners were collected and compared with data from Texas, California, and the south of England. The results show significant differences in how Greek listeners hear the tritone stimuli, as compared to listeners in the other groups. There is also evidence that the Greek listeners may have developed two different pitch class templates, possibly representing the influence of English and the influence of Greek.
Visual Study on Flow Behavior in an Inclined Two-Phase Closed Thermosyphon

A flow uisualization study of the inside flow phenomena of an inclined, two-phase, closed thermosyphom at several angles has been conducted. This article describes the detail of the flow patterns varying with the inclination angle. A thermosyphon with a total length about 930 mm was used, and its evaporator and adiabatic sections were provided with 13-mm-l.D. glass tubing for flow visualization. Freon 113 was charged as the working fluid. Observation of flow phenomena was done at selected inclination angles, such as 90, 80, 70, 60, 55, 45, 35, 20, and 5°. Flow phenomena were recorded with a standard video camera and a still camera, and the corresponding heat transfer rate was also measured. It was found that the typical flow patterns at several angles are classified by inclination angle, such as an annular flow at vertical or very near the vertical position, and a stratified flow at other angles. Moreover, in the case of a stratified flow, the occurrence of dryout on the evaporator wall is caused by the d.
THE SOLUTION OF SOME PERTURBATION PROBLEMS FOR MATRICES AND SELFADJOINT OR NON-SELFADJOINT DIFFERENTIAL EQUATIONS I

CONTENTSIntroductionChapter 1. The perturbation of symmetric and non-symmetric matrices § 1. Introduction § 2. The perturbation of solutions of linear algebraic equations § 3. The perturbation of eigenvalues and eigenvectorsChapter 2. The perturbation of selfadjoint and non-selfadjoint boundary problems § 4. Perturbation without raising the order of the differential operator § 5. Perturbation by operators of higher order § 6. The case in which the limit problem is on the spectrum § 7. The perturbation of eigenvalues and eigenfunctionsAppendix I. The perturbation of eigenvalues and eigenvectors (the general case)Appendix II. The convergence of the series for λe and veAppendix III. The perturbation of boundary problems by means of differential operators of higher order (general boundary conditions)References
Sorption-Caused Attenuation and Delay of Water Vapor Signals in Eddy-Covariance Sampling Tubes and Filters

AbstractAdsorption and desorption (together called sorption) processes in sampling tubes and filters of eddy-covariance stations cause attenuation and delay of water vapor signals, leading to an underestimation of water vapor fluxes by tens of percent. The aim of this work was (i) to quantify the effects on sorption in filters and tubes of humidity, flow rate, and dirtiness and (ii) to test a recently introduced sorption model that facilitates correction of fluxes. Laboratory measurements on the transport of water vapor pulses through tubes and filters were carried out, and eddy-covariance field measurements were also used.In the laboratory measurements, the effects of sorption processes were evident, and filters caused a similar attenuation and delay of the signal as tubes. Filters could have a larger impact than a long tube, whereas the flow rate had a much smaller impact on the flux loss than the sorption processes (Reynolds numbers 2120–3360). The sorption model represented well the water vapor pulses.
Characteristics of the equilateral triangular patch antenna

The results of a comprehensive analysis of this antenna based on the cavity model with a coaxial feed source are given. The theoretical formulas are given, and the characteristics obtained from them are presented, including radiation patterns, percentages of power radiated, total Q-factors, input impedances, and their variations with feed position. A number of disagreements with previously published results are noted. The theoretical and experimental results are compared. The results of the comparison indicate that the equilateral triangular patch can be designed to function as a triple frequency antenna. A method for correcting for the nonperfect magnetic wall is suggested. >
Dynamic Characteristic Analysis Considering Core Losses in Transverse Flux Linear Machine With Solid Cores

This paper deals with a method for dynamic characteristic analysis considering core losses in transverse flux linear machines (TFLMs) with solid cores. This paper focuses on how to calculate the core losses of solid cores and how to apply the core losses to the dynamic simulation. The magnetic field characteristics, which are used for the core loss calculation and dynamic simulation, are calculated by using a 3-D equivalent magnetic circuit network analysis method. The accuracy of the proposed core loss calculation and dynamic simulation methods are examined by comparing the input currents of the dynamic simulation model with the measured input current of two TFLM prototypes.
Summer Ice Crystal Precipitation at the South Pole

Abstract Ice crystal precipitation was observed and the crystals replicated, at the South Pole during January and February 1974. The crystals were of columnar form. These columns were hollow or prismatic, and sometimes were in the form of combinations of bullets. These combinations were very fragile, disintegrating into individual bullets upon impaction. Smaller “diamond dust” crystals were observed on two occasions. NOAA-NWS radiosonde data showed that the air was supersaturated with respect to ice at 650 to 600 mb (i.e., just above the surface) throughout the period. Ice crystal precipitation was only observed at the surface when cirrus bands were present at higher altitudes. It is likely that ice crystals, descending from the cirrus only a short distance above, grew to the larger columnar crystals while falling through the moist layer. As these layers were able to remain saturated, without precipitating or forming ice fogs or clouds at temperatures of −35°C, heterogeneous freezing nuclei were probably .
Comparing the Reliability of Difference Scores and Residuals in Analysis of Covariance

In pretest-posttest designs, residual scores created in the analysis of covariance commonly are preferred to difference scores because the latter suffer from reliability problems. This paper develops the reliability of residuals adjusted for a single covariate for comparison to the reliability of difference scores. Comparisons reveal that little is gained by analysis of covariance, which also suffers from reliability problems as the pretest and posttest reliabilities decrease and as their intercorrelation increases.
Femtosecond laser ablation of brass in air and liquid media

Laser ablation of brass in air, water, and ethanol was investigated using a femtosecond laser system operating at a wavelength of 785 nm and a pulse width less than 130 fs. Scanning electron and optical microscopy were used to study the efficiency and quality of laser ablation in the three ablation media at two different ablation modes. With a liquid layer thickness of 3 mm above the target, ablation rate was found to be higher in water and ethanol than in air. Ablation under water and ethanol showed cleaner surfaces and less debris re-deposition compared to ablation in air. In addition to spherical particles that are normally formed from re-solidified molten material, micro-scale particles with varying morphologies were observed scattered in the ablated structures (craters and grooves) when ablation was conducted under water. The presence of such particles indicates the presence of a non-thermal ablation mechanism that becomes more apparent when ablation is conducted under water.
Information Theory and Reliable Communication

Communication Systems and Information Theory. A Measure of Information. Coding for Discrete Sources. Discrete Memoryless Channels and Capacity. The Noisy-Channel Coding Theorem. Techniques for Coding and Decoding. Memoryless Channels with Discrete Time. Waveform Channels. Source Coding with a Fidelity Criterion. Index.
Geodesics in two-dimensional first-passage percolation

We consider standard first-passage percolation on Z 2 . Geodesics are nearest-neighbor paths in Z 2 , each of whose segments is time-minimizing. We prove part of the conjecture that doubly infinite geodesics do not exist. Our main tool is a result of independent interest about the coalescing of semi-infinite geodesics.
Assimilating Cloud Water Path as a Function of Model Cloud Microphysics in an Idealized Simulation

AbstractThe sensitivity of assimilating satellite retrievals of cloud water path (CWP) to the microphysics scheme used by a convection-allowing numerical model is explored. All experiments use the Advanced Research core of the Weather Research and Forecasting Model (WRF-ARW), with observations assimilated using the Data Assimilation Research Testbed ensemble adjustment Kalman filter and a 40-member ensemble. Three-dimensional idealized supercell simulations are generated from a deterministic WRF nature run started from a homogeneous set of initial conditions. Four cloud microphysics schemes are tested: Lin–Farley–Orville (LFO), Thompson (THOMP), Morrison double-moment (MOR), and Milbrandt–Yau (MY). For the idealized experiments, assimilating CWP generates a mature supercell after approximately 1 h for all microphysics schemes. Vertical profiles of ensemble covariances show large differences in the relationship between CWP and various hydrometeor mixing ratios. While the differences in overall CWP are small.
Ion distributions and flows near the neutral sheet

In this paper, the authors present a survey of the three-dimensional ion and electron distributions measured on AMPTE IRM near the neutral sheet in the near-Earth magnetotail (R {approx} 10{minus}19 R{sub E}). The data are classified according to substorm phases. Individual case studies of velocity distributions reveal that the ions in the neutral sheet consist of a single population. Fast and slow flows both occurred during the two extremes of magnetospheric activity, the substorm expansion phase and quiet times. Ion beams are occasionally observed, and their shapes in velocity space are similar to those observed in the plasma sheet boundary layer. A ring distribution is seen only twice in 50 events. The occurrence rate of fast flows is postively correlated with the global magnetic field elevation during disturbed times and anticorrelated with that elevation during quiet times. The global magnetic field elevation angle is related to the magnetic field configuration in the magnetotail. Therefore their results indicate a dependence of the flow speed within the neutral sheet on the magnetotail configuration at the point of observation.
Determination of elastic strain fields and geometrically necessary dislocation distributions near nanoindents using electron back scatter diffraction

The deformation around a 500-nm deep Berkovich indent in a large grained Fe sample has been studied using high resolution electron back scatter diffraction (EBSD). EBSD patterns were obtained in a two-dimensional map around the indent on the free surface. A cross-correlation-based analysis of small shifts in many sub-regions of the EBSD patterns was used to determine the variation of elastic strain and lattice rotations across the map at a sensitivity of ∼±10−4. Elastic strains were smaller than lattice rotations, with radial strains found to be compressive and hoop strains tensile as expected. Several analyses based on Nye's dislocation tensor were used to estimate the distribution of geometrically necessary dislocations (GNDs) around the indent. The results obtained using different assumed dislocation geometries, optimisation routines and different contributions from the measured lattice rotation and strain fields are compared. Our favoured approach is to seek a combination of GND types which support the six measurable (of a possible nine) gradients of the lattice rotations after correction for the 10 measurable elastic strain gradients, and minimise the total GND line energy using an L1 optimisation method. A lower bound estimate for the noise on the GND density determination is ∼±1012 m−2 for a 200-nm step size, and near the indent densities as high as 1015 m−2 were measured. For comparison, a Hough-based analysis of the EBSD patterns has a much higher noise level of ∼±1014m−2 for the GND density.