Miracle-dz/UniFAR-FTUs huggingface dataset:
Evaluation of procedural changes for minimizing noise impact near military airfields

Over time, communities surrounding military airfields tend to grow, while the noise generated by subsequent generations of military aircraft tends to increase. This creates an accelerating problem of human exposure to noise. One technique to alleviate this disparity is to modify attributes of flight trajectories in a way that reduces the sound exposure of the population. This involves the changing of flight ground tracks, profiles, and power settings within linear and non-linear boundaries which can include exceptions (such as no-fly-zones.) To demonstrate the effectiveness of these changes, DNL levels are calculated for real world population distributions and existing Navy departure procedures. These values are generated computationally using the widely accepted NoiseMap model. It is shown that significant reductions of exposure averaged over the population can be achieved in this way. Possible methods for automating this procedure are discussed. Properties of the objective function spaces are explored (.
Rheocasting of Aluminum Alloy A356 based on Various Parameters: A Review

Out of many casting techniques, semisolid casting has been proven to be one of the most reliable methods of metal processing, especially on the likes of aluminum, magnesium and copper based alloys. This method offers many advantages over other liquid and solid processing techniques. Many researchers have worked through this technique, in order to define the potential of this process in producing different products especially for automotive industry. This work narrates through the various techniques involved in Rheocasting of aluminum A356 alloy, based on many research works, which have wide range of application in industries. Heat treatment response, fracture behavior, wear behavior, micro-structural evolution are some of the phenomenon’s that have been discussed in this review. A356 and A357 are the most commonly used aluminum alloys, used to obtain near net shaped products because of the relatively high volume of AlSi eutectic, which gives fluidity and better castability. Over the course, rheocast aluminum A356 alloy have been compared with many other competing alloy materials.
Speed-Up in Dynamic Programming

Dynamic programming is a general problem-solving method that has been used widely in many disciplines, including computer science. In this paper we present some recent results in the design of efficient dynamic programming algorithms. These results illustrate two approaches for achieving efficiency: the first by developing general techniques that are applicable to a broad class of problems, and the second by inventing clever algorithms that take advantage of individual situations.
A simple general proof of the Krazer–Prym theorem and related famous formulae resolving convergence properties of Coulomb series in crystals

The Krazer–Prym theorem extending the Poisson summation formula to oblique lattices is proved as a direct consequence of translational symmetry. A generalized Ewald approach based on this theorem is reproduced. The two other famous approaches proposed by Nijboer and De Wette, and by Harris and Monkhorst, are derived in the same fashion. The absence of any uniform contribution to bulk electrostatic potentials in each of those treatments is emphasized as a property of locally neutral systems subject to translational symmetry. It is found that an analytic evaluation of the Ewald variable parameter naturally follows from the treatment of the Coulomb lattice characteristic in terms of the Krazer–Prym theorem. The extension of those characteristics to off-lattice points is also discussed.
Limit theorems for sums of general functions of m-spacings

Laws of large numbers and central limit theorems are proved for sums of general functions of m-spacings from general distributions. Explicit formulae are given for the norming constants. The results enable us to describe asymptotic properties of distributional tests under fixed alternatives. A generalization of Kimball's spacings test is considered in detail.
Validating Identified Nonlinear Models with Chaotic Dynamics

This paper investigates the effectiveness of several criteria for validating models which exhibit chaotic dynamics. Embedded trajectories, Poincare sections, bifurcation diagrams, the largest Lyapunov exponent and correlation dimension are considered. The Duffing-Ueda equation and four identified models are used as examples. The results show that models with similar invariants such as Poincare sections, the largest Lyapunov exponent and correlation dimension may have very different bifurcation behaviours. This suggests that the requirement that an identified model should reproduce the bifurcation pattern of the original system is a very exacting criterion which is well suited for validation purposes.
Dense cores in dark clouds. II. NH3 observations and star formation.

We present partial results of a survey of approx.100 visually opaque regions in nearby dark clouds in the 1.3 cm (J,K) = (1,1) line of NH/sub 3/, with mapping of all strong sources (''dense cores'') and (2,2) line observations in selected positions. For 27 dense cores with distance estimates, mean properties are: FWHM diameter, 0.1 pc; density, 3 x 10/sup 4/ cm/sup -3/; mass, 4 M/sub sun/; kinetic temperature, 11 K; and FWHM velocity width, 0.3 km s/sup -1/. We compare line shapes with cloud motion models, and source density, size, and temperature with equilibrium and stability requirements. These indicate that most dense cores are in the early stages of collapse or in near-critical equilibrium; if in equilibrium, they are probably supported by a combination of thermal and subsonic turbulent motions. In Taurus-Auriga, positions of the 10 known dense cores are well correlated with positions of emission-line star groups. In the next dense core free-fall time, 2 x 10/sup 5/ yr, the Taurus-Auriga complex is expected to form 25--50 emission-line stars. This is consistent with the estimated number of dense cores, 25. Taken together, these results suggest that most of the dense cores described here will form low-mas stars inmore » the next approx.10/sup 6/ yr. « less
Optical interferometric polarimetry

In this paper, I discuss the need for optical interferometric polarimetry and demonstrate that it is possible with existing technology. Coherent averaging is required; it may be accomplished simply with the addition of a non-polarizing beam splitter after the beam combiner. I define three observables and their corresponding output vectors. One vector is identical to the normalized Stokes vector obtained from classical polarimetry, while the other two are related to the Stokes visibility vector. Calibration of the instrument requires only separate zero-spacing observations of calibrator stars on each of the individual arms - no interferometric measurements are necessary. For a large class of objects, it is possible to create images in all Stokes parameters with a single variable-length baseline.
Design Adaptive Nearest Neighbor Regression Estimation

This paper deals with nonparametric regression estimation under arbitrary sampling with an unknown distribution. The effect of the distribution of the design, which is a nuisance parameter, can be eliminated by conditioning. An upper bound for the conditional mean squared error of k? NN estimates leads us to consider an optimal number of neighbors, which is a random function of the sampling. The corresponding estimate can be used for nonasymptotic inference and is also consistent under a minimal recurrence condition. Some deterministic equivalents are found for the random rate of convergence of this optimal estimate, for deterministic and random designs with vanishing or diverging densities. The proposed estimate is rate optimal for standard designs.
Brownian Motion of Microscopic Solids under the Action of Fluctuating Electromagnetic Fields

The Brownian motion of a microscopic solid under the action of fluctuating electromagnetic fields was detected using atomic-force microscopy. The distance dependence of the noise spectrum of free cantilever oscillations, of the resonance frequency, and of the damping coefficient were investigated under ultrahigh vacuum conditions. An analytic expression for the damping coefficient of a metallic tip\char21{}sample system was obtained on the basis of fluctuating electrodynamics. Our calculation is in good agreement with experimental data.
An engineer–oriented optimisation of Stirling engine cycle with finite–size finite–speed of revolution thermodynamics

Finite–time thermodynamics takes into account exo–irreversibilities which are not managed by reversible thermodynamics, especially reservoir–to–gas temperature gaps. In today's works, thermodynamicists use the working gas mass as the main imposed parameter. In this paper, the study of the Stirling engine cycle is carried out with a motorist–oriented viewpoint: instead of the working gas mass, the reference parameters are those linked to engineering constraints; they are the maximum pressure, the maximum volume, the extreme temperatures and the overall thermal conductance; the adjustable parameters are the volumetric compression ratio, the hot–to–cold conductance ratio and the regenerator efficiency. Analytical normalised expressions of the operating characteristics of the engine, such as power, work, efficiency, speed and their optima are set up. Classical results of analytical optimisation are found back and new ones are established, leading to new conclusions. Some dimensionless and dimensional numbers are put into evidence.
The effect of category choice on the odds ratio and several measures of association in case-control studies

In many case-control studies the risk factors are categorized in order to clarify the analysis and presentation of the data. However, inconsistent categorization of continuous risk factors may make interpretation difficult. This paper attempts to evaluate the effect of the categorization procedure on the odds ratio and several measures of association. Often the risk factor is dichotomized and the data linking the risk factor and the disease is presented in a 2 x 2 table. We show that the odds ratio obtained from the 2x2 table is usually considerably larger than the comparable statistic that would have been obtained had a large number of outpoints been used. Also, if 2 x 2, 2 x 3, or 2 x 4 tables are obtained by using a few outpoints on the risk factor, the measures of association for these tables are usually greater than the measure that would have been obtained had a large number of cntpoints been used. We propose an odds ratio measure that more closely approximates the odds ratio between the continuous .
Observations of the impact of starbursts on the interstellar medium in dwarf galaxies

Dwarf galaxies play a crucial role in our understanding of the formation and evolution of galaxies, and the concept of supernova-driven mass outflows is a vital ingredient in theories of the structure and evolution of dwarf galaxies. Despite the theoretical importance of these outflows, there is a very limited amount of direct observational evidence for their existence. We have therefore begun a detailed multi-wave-band search for outflows in dwarf (M(sub B) greater than or = -18) galaxies with extensive recent or ongoing centrally concentrated star formation. We report the first results of this search in the present paper. Observations of the ionized gas in dwarf amorphous galaxies with centrally concentrated populations of massive stars provide evidence for the large-scale expansion of their expansion of their ionized interstellar media. Fabry-Perot H alpha images reveal the presence of kiloparsec-scale 'superbubbles' and filaments which tend to be oriented along the galaxy minor axis. These structures are comparable in size to the chracteristic optical sizes of the galaxies, and dominate the morphology of the galaxies at low surface brightness in H alpha. Since expanding structure of this size and velocity are not observed in all low-mass galaxies with recent or ongoing star formation, we suggest that we are witnessing transient events that likely have a relatively low 'duty cycle' in such galaxies. That is, we argue that the particular galaxies in the present paper have had significantly elevated star formation rates over the past 10(exp 7)-10(exp 8) yr (i.e., these are starburst or young poststarburst systems). This interpretation is consistent with the optical colors and emission-line properties of these galaxies.
Infrared Spectroscopy of Pa-beta and [Fe II] Emission in NGC 4151

We present spatially resolved 1.24-1.30 micron spectroscopy with a resolution of 240 km/s of the Seyfert 1.5 galaxy NGC 4151. Broad Pa-beta, narrow Pa-beta, and narrow [Fe II] (lambda = 1.2567 micron) emission lines are identified in the spectrum. Additionally, a spatially unresolved narrow component probably due to [S ix] (lambda = 1.25235 micron) is observed on the nucleus. The narrow Pa-beta and [Fe II] lines are observed to be extended over a scale of 5 sec. The spatial variation of the velocity centers of the Pa-beta and [Fe II] lines show remarkable similarity, and additionally show similarities to the velocity structure previously observed in ground based spectroscopy of [O III] emission in NGC 4151. This leads to the conclusion that the [Fe II] emission arises in clouds in the Seyfert narrow line region that are physically correlated with those narrow line clouds responsible for the optical emission. The [Fe II] emission line, however, is significantly wider than the Pa-beta emission line along the full spatial extent of the observed emission. This result suggests that despite the correlation between the bulk kinematics of Pa-beta and [Fe II], there is an additional process, perhaps fast shocks from a wind in the Seyfert nucleus, contributing to the [Fe II] emission.
The acoustic survey of intonation in Autism Spectrum Disorder

The speech pattern of children with autism spectrum disorder (ASD) demonstrates a number of abnormal features, the study which can shed light on the difficulties the autistic children encounter in making meaning through speech. With regard to this stated purpose, in this article, I have scientifically examined the pattern of speech in a set of indicative and interrogative sentences as uttered by a group of autistic children and compared and contrasted the results with the pattern of speech in the same set of sentences as uttered by a group of typical development (TD) children. The specific aim of this study was to assess the intonation pattern, mean of pitch, amplitude, duration, intensity, and tilt in the ASD as compared to the TD. The data collected showed that while the amplitude in interrogative sentences, duration, intensity, mean of pitch, and tilt in ASD and TD were almost similar, the intonation pattern, the mean of pitch (with regard to severity of autism), and the amplitude in indicative sentences proved significantly different. To be more precise, with respect to these three latter features, the autistic children demonstrated monotony, an impairment that made them have difficulty making meaningful indicative and interrogative sentences.
Clustering work and family trajectories by using a divisive algorithm

Summary. We present an approach to the construction of clusters of life course trajectories and use it to obtain ideal types of trajectories that can be interpreted and analysed meaningfully. We represent life courses as sequences on a monthly timescale and apply optimal matching analysis to compute dissimilarities between individuals. We introduce a new divisive clustering algorithm which has features that are in common with both Ward's agglomerative algorithm and classification and regression trees. We analyse British Household Panel Survey data on the employment and family trajectories of women. Our method produces clusters of sequences for which it is straightforward to determine who belongs to each cluster, making it easier to interpret the relative importance of life course factors in distinguishing subgroups of the population. Moreover our method gives guidance on selecting the number of clusters.
Effects of positron density and temperature on ion-acoustic solitary waves in a magnetized electron-positron-ion plasma: Oblique propagation

Ion-acoustic (IA) solitary waves are investigated in a magnetized three-component plasma consisting of cold ions, isothermal hot electrons, and positrons. The basic set of fluid equations is reduced to the Korteweg de Vries equation using the standard reductive perturbation (multiple-scale) technique. Theoretical and numerical analyses confirm significant effects of the presence of positrons and the dependence of the electron to positron temperature ratio on the amplitude and the width of IA solitary waves. It is shown that the rarefactive and compressive IA solitary excitations can propagate when the propagation angle θ satisfies 0≤θ<π/2 and π/2<θ≤π, respectively. Also, it is remarked that the amplitude of the rarefactive and compressive IA solitary excitations is not affected by the magnitude of external magnetic field B0, whereas their width depends strictly on B0. The numerical analysis has been done based on the typical numerical data from a pulsar magnetosphere.
Unified Numerical Procedure for Compressible and Incompressible Fluid

A unified numerical procedure is proposed as a solver both for compressible and incompressible fluids. The method approaches the MAC algorithm at very high sound speed and continuously approaches the algorithm for compressible fluid with decreasing sound speed. The advection term is treated by the CIP algorithm which was previously proposed and gives quite accurate and less-diffusive results. This unified procedure is tested both by one-dimensional shock-tube problem and two-dimensional cavity flow at high-Reynolds number.
A numerical technique for analyzing electromagnetic wave scattering from moving surfaces in one and two dimensions

The electromagnetic wave scattering properties of a moving, perfectly conducting mirror are analyzed using a numerical technique based on the finite-difference time domain (FD-TD) method. This numerical technique does not require a system transformation where the object is at rest, but gives a solution to the problem directly in the laboratory frame. Two canonical one-dimensional cases are considered, the uniformly moving and the uniformly vibrating mirror. Numerical results for the scattered field spectrum are compared to available analytical results, and an excellent agreement is demonstrated. The ability of the FD-TD model to obtain the physics of the double-Doppler effect (for the uniform translation case), and frequency-modulation-like reflected spectrum (for the uniform vibration case) is highlighted. The method is then extended to two-dimensions where a plane wave at oblique incidence on an infinite vibrating mirror is considered. A good agreement with published results is demonstrated for this case. >
THE DUSTY CIRCUMSTELLAR DISKS OF B[e] SUPERGIANTS IN THE MAGELLANIC CLOUDS

To better ascertain the nature of the infrared excesses that are characteristic of B[e] supergiants, we obtained Spitzer IRS spectroscopy and IRAC/MIPS imaging for a sample of nine B[e] supergiant stars in the Magellanic Clouds. We find that all nine stars display mid- to far-IR spectral and spatial characteristics indicative of the presence of circumstellar dust disks. Several of the sample B[e] supergiants display crystalline silicate features in their IRS spectra, consistent with grain processing in long-lived (i.e., orbiting) disks. Although it is possible that these disks are primordial in origin, large shell structures (with size scales of tens of parsec) are associated with five of the nine B[e] supergiants, suggesting that mass loss has provided the circumstellar material now orbiting these stars. Hence—via analogy to the class of post-asymptotic giant branch stars with binary companions and dusty, circumbinary disks—we speculate that B[e] supergiant stars may be post-red supergiants in binary systems with orbiting, circumbinary disks that are derived from post-main-sequence mass loss.
Return Anomalies on the Nikkei: Are They Statistical Illusions?

This study investigates the sensitivity of the long-term return anomaly observed on the Nikkei stock index to sample and method bias using daily data from the period 3 January 1980 to 31 October 2000. Initially, the CUSUM statistic is employed to identify sub-periods of sign shifts in the mean returns. We find that the null hypothesis of no long-term dependence is accepted for the whole sample and every sub-period using the modified rescaled range test, but not using the classical rescaled adjusted range test. We conclude that researchers may inadvertently introduce sample and method bias into their studies of the time series properties of the Nikkei unless sample period and method are considered.
Axial shear waves in a medium with randomly distributed cylinders

The propagation of coherent elastic shear waves in a medium containing a dilute and uniform distribution of cylindrical inclusions is discussed. The waves are assumed to be polarized parallel to the axes of the cylinders while the cylinders are assumed to be thin compared to the wavelength. The complex wavenumber is calculated to a second order of approximation, the real part of which gives the propagation speed and the imaginary part gives the damping due to scattering. Numerical results are obtained for the case of identical inclusions with the properties of the inclusions varying between hollow (void) and rigid.
Puzzle of Corporate Diversification Efficiency in BRIC Countries

Researchers have long tried to define the impact of corporate diversification on firm value. Academic papers mainly concentrate on the effects of corporate diversification in mature markets while its consequences in emerging capital markets are less explored. This article presents the results of an empirical analysis of corporate diversification strategies of a sample of companies from BRIC countries that expanded via acquisitions during 2000–2013. We contribute to the existing literature by examining the effects of corporate diversification on firm value during the pre- and post-crisis periods. In line with other studies, we distinguish between related and unrelated diversification and in contrast to them we single out and separately analyze horizontal, conglomerate and vertical acquisitions. Based on a sample of 319 deals initiated by companies from BRIC countries, we found positive (3.32% and 9.01%) and statistically significant cumulative abnormal returns for conglomerate acquisitions during the pre- and post-crisis periods, correspondingly. We also found that the market reacts positively and statistically significant to the announcements of horizontal and vertical integration only during the pre-crisis period.
Compaction wave profiles: Simulations of gas gun experiments

Mesoscale simulations of a compaction wave in a granular bed of HMX have been performed. The grains are fully resolved in order that the compaction, i.e., the porosity behind the wave front, is determined by the elastic-plastic response of the grains rather than by an empirical law for the porosity as a function of pressure. Numerical wave profiles of the pressure and velocity are compared with data from a gas gun experiment. The experiment used an initial porosity of 36%, and the wave had a pressure comparable to the yield strength of the grains. The profiles are measured at the front and back of the granular bed. The transit time for the compaction wave to propagate between the gauges determines the wave speed. The wave speed depends on the porosity behind the wave and is affected by the strength model. The yield strength needed to match the experimental wave speed is discussed. Analysis of the lead wave through the granular bed, based on impedance matches using the Hugoniot loci, indicates that the com.