Miracle-dz/UniFAR-FTUs huggingface dataset:
The anomalous bandgap bowing in GaAsN

The composition dependence of the fundamental bandgap of thin, pseudomorphic GaAs1−xNx layers (0⩽x⩽5%) on GaAs substrates is studied by optical transmission measurements and high resolution x-ray diffraction. We present a very large set of consistent experimental data. An empirical double exponential composition dependence of the bowing parameter is obtained. This expression accurately describes the measured bandgaps, and allows estimations for higher N incorporations. The bowing parameter reaches 40 eV for very low N incorporations (x≈0.1%), and strongly decreases with increasing N molar fraction. We estimate that the bowing parameter would reach a constant value of 7.5 eV for x≳8%, as in an alloy. This bowing would not be sufficient to close the bandgap for higher N incorporations.
Minimization of transverse beam-emittance growth in the 90-degree bending section of the RAON rare-isotope accelerator

The major contribution of the transverse beam emittance growth (EG) in a RAON heavy-ion accelerator comes from the bending section, which consists of a charge-stripping section, a matching section, and a charge-selection section in sequence. In this paper, we describe our research to minimize the two-dimensional EG in the 90-degree bending section of the RAON currently being developed in Korea. The EG minimization was achieved with the help of multi-objective genetic algorithms and the simplex method. We utilized those algorithms to analyze the 90-degree bending section in a driver linac for the in-flight fragmentation system. Horizontal and vertical EGs were limited to below 10 % in the bending section by adjustment of the transverse beam optics upstream from the charge-stripping section, redesign of the charge-selection section, and optimization of the vertical beam optics at the entrance of a charge-selection section.
Photoelectric effect: Back to basics

The measurement of Planck’s constant by use of the photoelectric effect has long been a cornerstone experiment of the introductory modern physics laboratory. In this paper, the classic experiment is revisited in order to place more emphasis on the physics of the photoemission process. Toward this end, a measurement and theoretical analysis of the quantum yield of a commercial photocell are presented. Near the photoemission threshold, the quantum yield Y is shown to go as (hν−φc)2, where φc is the work function of the metal photocathode. Hence, φc can be determined from an experimental plot of Y1/2 vs hν. In addition, justification is given for a procedure used for many years to determine the stopping potential from a plot of (photocurrent)1/2 versus applied bias voltage.
The Performance of Kolmogorov–Smirnov Statistic in Noise Identification

Noise identification is one of the most important issues in radar and sonar engineering, in which Kolmogorov–Smirnov (KS) statistic is widely adopted. Although KS statistic is the most reliable method till now, it does not have high precision as people believe. The performance of KS statistic is studied in this work, while an experiment is carried out to show the precision of KS statistic, including both test and recognition. The result could help researchers decreasing error of using KS statistic in the future.
Germination of bean seeds ( Phaseolus vulgaris L.) at different temperatures

The research was developed in the Base Scientific Science Unit, Los Palacios, Pinar del Río, Cuba, belonging to the National Institute of Agricultural Sciences. The objective was to evaluate the influence of temperatures on the germination of four bean cultivars. Seeds of Phaseolus vulgaris L. (beans) were analyzed from the cultivars, Cubana 23, Chévere, Buena Ventura, La Cuba 154. The germination temperatures considered in each trial were 20, 30 and 40 ºC. The experimental design used was completely randomized in all cases, each trial was evaluated individually and was repeated twice, it worked with the means of these repetitions. Germinated seeds were counted from their establishment until stabilization, with the obtained data: germination percentage, germinated seeds per day and the Maguire Index were determined. The results were subjected to an analysis of variance (ANOVA) with a confidence level of 99 %. The results of this work indicate that there is sensitivity of different bean cultivars to a variation in temperature in the germination process; therefore, the effect of temperature is closely related to the genetic material that is being worked on. Temperatures higher than 30 ºC decrease the germination speed in cultivars under study
A Model for the Spectral Albedo of Snow. I: Pure Snow

Abstract We present a method for calculating the spectral albedo of snow which can be used at any wavelength in the solar spectrum and which accounts for diffusely or directly incident radiation at any zenith angle. For deep snow, the model contains only one adjustable parameter, an effective grain size, which is close to observed grain sizes. A second parameter, the liquid-equivalent depth, is required only for relatively thin snow. In order for the model to make realistic predictions, it must account for the extreme anisotropy of scattering by snow particles. This is done by using the “delta-Eddington” approximation for multiple scattering, together with Mie theory for single scattering. The spectral albedo from 0.3 to 5 μm wavelength is examined as a function of the effective grain size, the solar zenith angle, the snowpack thickness, and the ratio of diffuse to direct solar incidence. The decrease in albedo due to snow aging can be mimicked by reasonable increases in grain size (50–100 μm for new snow.
A novel microstructure: Semiconductor‐impregnated porous Vycor glass

Porous Vycor glass has been impregnated with selenium and tellurium by pressure forcing the nonwetting semiconductor melt into the interconnected pores. Dense semiconductor microstructures with a characteristic size of 50 A can be fabricated by this technique. Measurements are reported which show the composite is suitable for both optical and electrical transport studies, particularly those addressing possible quantum confinement of carriers in this class of materials.
An Algorithm for Generalized Matrix Eigenvalue Problems.

A new method, called the $QZ$ algorithm, is presented for the solution of the matrix eigenvalue problem $Ax = \lambda Bx$ with general square matrices A and B. Particular attention is paid to the degeneracies which result when B is singular. No inversions of B or its submatrices are used. The algorithm is a generalization of the $QR$ algorithm, and reduces to it when $B = I$. Problems involving higher powers of $\lambda $ are also mentioned.
Optimal design of Toraldo super-resolving filters

Pupil plane filtering provides a convenient technique for modifying the point spread function. Such modifications are used in many practical applications that require enhancement of selective frequency band in images. Also, in many new imaging paradigms, acquisition of 3D image information calls for tailoring of the 3D point spread function. This can be achieved by suitable pupil plane filtering, preferably by phase filters. By using a pupil plane filter with an array of concentric annuli, the point spread function can be tailored in a fashion such that a narrow central lobe is surrounded by neighboring lobes of low amplitude, with one or more lobes of high amplitude spaced far away from the center. In our study we intend to explore the use of phase annuli as pupil filters in tailoring of both transverse and axial resolution. Determination of such phase filters in accordance with a set of prespecified requirements for amplitude/intensity distribution around the focus constitutes a problem of nonlinear optimization. This paper reports some results of our preliminary investigations on an application of evolutionary programming in solving this problem to obtain globally or quasi-globally optimum solutions.
Case study: the introduction of stereoscopic games on the Sony PlayStation 3

A free stereoscopic firmware update on Sony Computer Entertainment's PlayStation® 3 console provides the potential to increase enormously the popularity of stereoscopic 3D in the home. For this to succeed though, a large selection of content has to become available that exploits 3D in the best way possible. In addition to the existing challenges found in creating 3D movies and television programmes, the stereography must compensate for the dynamic and unpredictable environments found in games. Automatically, the software must map the depth range of the scene into the display's comfort zone, while minimising depth compression. This paper presents a range of techniques developed to solve this problem and the challenge of creating twice as many images as the 2D version without excessively compromising the frame rate or image quality. At the time of writing, over 80 stereoscopic PlayStation 3 games have been released and notable titles are used as examples to illustrate how the techniques have been adapted for different game genres. Since the firmware's introduction in 2010, the industry has matured with a large number of developers now producing increasingly sophisticated 3D content. New technologies such as viewer head tracking and head-mounted displays should increase the appeal of 3D in the home still further.
Design study of a superconducting gantry for carbon beam therapy

This paper describes beam-optics design of a gantry for carbon ions in cancer therapy accelerators. A compact design is important for such a gantry. The designed gantry is compact such that its size is comparable to the size of the existing proton gantries. This is made possible by introducing superconducting double helical coils for dipole magnets. The gantry optics is designed in such a way that it provides rotation-invariant optics, a variable beam size, and point-to-parallel scanning of a beam. For large-aperture magnet, a three-dimensional magnetic field distribution is obtained by invoking a computer code, and a number of particles are tracked by integrating equations of motion numerically together with a three-dimensional interpolation. The beam-shape distortion due to the fringe field is reduced to an acceptable level by optimizing the coil windings with the help of a genetic algorithm. Higher-order transfer coefficients are calculated and shown to be reduced greatly with appropriate optimization of the coil windings.
Direct calculation of the Berry phase for spins and helicities

The Berry phase for spins or helicities is calculated in a simple way in which it appears more as a property of the spin states than of the Hamiltonian. The calculation applies to nonrelativistic particles or relativistic particles with either zero or nonzero mass. A simple way to see how the Berry phase corresponds to rotation of the electric and magnetic fields of plane‐polarized light is also pointed out.
Fluorescence spectra of isolated molecules in neon and argon matrices: assignment of the lowest emitting states

Highly structured fluorescence is reported for C60 mols. isolated in Ne and Ar matrixes. Their excitation spectra are similar to the gas-phase 2-photon ionization spectrum of C60. Most of the bands seen in emission can be attributed to Herzberg-Teller or Jahn-Teller active modes and to combinations of these modes. The intensity distribution of the fluorescence bands is compared with calcd. intensities and shows that the emission is of mixed singlet T1g and T2g character in Ne matrixes in nearly equal proportions and of mixed singlet T1g and Gg character in Ar matrixes, in a proportion of 4 to 1 in favor of the T1g state. The band frequencies show that these 3 states are degenerate to within exptl. uncertainty and the authors est. their gas-phase energy at 15,695 +- 5 cm-1. The assignment of ground-state vibrational band frequencies are rediscussed. [on SciFinder (R)]
Direct adaptive control of non-affine nonlinear systems using multilayer neural networks

A direct adaptive control method is presented for a class of nonaffine nonlinear systems using multilayer neural networks (MNNs). The proposed controller ensures that the output of the system tracks a given bounded reference signal and the output tracking error converges to an /spl epsiv/-neighborhood of zero, while the stability of the closed-loop system is guaranteed by Lyapunov's stability theory.
A feasibility study of projection-based energy weighting based on a photon-counting detector in contrast-enhanced digital subtraction mammography: A simulation study

Contrast media, such as iodine and gadolinium, are generally used in digital subtraction mammography to enhance the contrast between target and background materials. In digital subtraction mammography, where one image (with contrast medium) is subtracted from another (anatomical background) to facilitate visualization of the tumor structure, tumors can be more easily distinguished after the injection of a contrast medium. In order to have more an effective method to increase the contrast-to-noise ratio (CNR), we applied a projection-based energy-weighting method. The purpose of this study is to demonstrate the feasibility of using the projection-based energy-weighting method in digital subtraction mammography. Unlike some other previous studies, we applied the projection-based energy-weighting method to more practical mammography conditions by using the Monte Carlo method to simulate four different iodine solutions embedded in a breast phantom comprised of 50% adipose and 50% glandular tissues. We also considered an optimal tube voltage and anode/filter combination in digital iodine contrast media mammography in order to maximize the figure-of-merit (FOM). The simulated source energy was from 20 to 45 keV to prevent electronic noise and include the k-edge energy of iodine (33.2 keV). The results showed that the projection-based energy-weighting improved the CNR by factors of 1.05–1.86 compared to the conventionally integrated images. Consequently, the CNR of digital subtraction mammography images can be improved by using projection-based energy-weighting with photon-counting detectors.
Determination of cross sections of excitation transfer between the fine-structure components of Cs(72P), Rb(62P) and Rb(72P) induced by collisions with rare-gas atoms

Cross sections of excitation transfer between the fine-structure sublevels of Cs(72P), Rb(62P) and Rb(72P) induced by collisions with rare-gas atoms have been determined from the time dependence of the sensitised fluorescence. The Cs and Rb atoms, contained in absorption cells filled with inert gases at different pressures, were excited using a pulsed dye laser pumped by a nitrogen laser. The fluorescence was observed time resolved employing a photon counting technique. The use of a two-level approximation allowed the Maxwellian (velocity) averaged transfer cross sections to be calculated. Comparison of the cross section values determined in this work with the values quoted by other authors shows good consistency in the case of Rb 62P inert-gas collisions while in the case of Cs 72P inert-gas collisions there are some discrepancies. Rb 72P excitation transfer has not been dealt with before.
Semi-Adaptive Nonparametric Spectral Estimation

Abstract When dominant information is available about a process, its corresponding spectral density will exhibit a variable order of smoothness. In such situations, calculating a nonparametric spectral estimate with a fixed smoothing parameter will lead to biased spectral estimates. We propose a simple method that allows the bandwidth of the spectral window in the smoothed periodogram running average procedure to vary in order to compensate for the possibly changing order of smoothness of the underlying spectral density. At each point of estimation, our approach is to extend the bandwidth until the squared variation of the periodogram within reaches a prespecified level. Our method may be particularly benevolent when the process is nonstationary with close spectral lines, although it may be implemented in any situation that warrants adaptive scatterplot “smoothing,” such as in those cases where sharp peaks are considered to be information and not error. We illustrate our method on an observed and simulate.
Proper Insulated Materials for Temperature Accumulation in Box Technology to Catalyze the Organic Digestion Processing on Community Garbage Disposal

The research is aimed to determine the appropriate insulated materials and the thickness of insulated boxes for keeping in-box temperature around 70 oC. The experiments were conducted by taking amount of 500 g river gravels (number 3) to heat in Hot air oven at 100 oC for 24 hours before putting in the 0.027 m3 (30x30x30 cm) insulated boxes. The in-box (T1) and out-box (T2) ambient air temperature were recorded by automatic data locker from beginning to the end of experiments. The relationship between time (t) and in-box temperature by graphical techniques in order to select the appropriate insulated material under the criterions of The King's Royally initiative nature-by-nature process, simplicity technology, and low expense (or local materials using for constructing technology), Also, the relations between Q (heat conduction) of temperature differences (in-box and outside box) in varying time (t) as same as the insulated material thickness was evaluated from graphical products of fixing T1 (equivalent to 70 oC) and Q of varying ambient air temperature. The results found that rice straw as the appropriate insulated material tether with the minimum rice-straw insulated thickness of 6 cm in which the in-box temperature could be kept long enough for psychrophiles, mesophiles, thermophiles, and hyper-thermopile to complete the digestion of carbohydrates, proteins, celluloses, hemicelluloses, and fibers. Moreover, the research result was also pointed out the values of ambient air temperature (from -10 oC to 70 oC) is inversely related to thickness of the rice-straw insulated boxes, by taking the minimum thickness of 6 cm for T2 equivalent to 30 oC.
Bridging GPS outages using neural network estimates of INS position and velocity errors

INS and GPS are commonly integrated using a Kalman filter (KF) to provide a robust navigation solution, overcoming situations of GPS satellite signals blockage. This research presents an alternative method of bridging GPS outages requiring no prior knowledge of the INS and GPS sensor characteristics, called the artificial-intelligence-based segmented forward predictor. This method uses radial basis function neural networks to predict INS position and velocity errors during GPS outages, resulting in reliable performance. The performance of the proposed method is examined using real field test data of both navigational and tactical grade INS integrated with GPS. The results have shown that the proposed method outperforms KF, especially during long GPS outages.
CFD-modelling of subcooled boiling

Abstract In this paper new developments in the framework of a common project simulating subcooled boiling are described. The computational model used combines the Euler/Euler two-phase flow description with heat flux partitioning. Main achievements were a comprehensive study of the boiling process itself and a better description of the interfacial area by coupling of wall boiling with a population balance model. The model extensions are validated and the present capabilities of CFD for wall boiling are investigated.
Light emission characteristics of blue strain-compensated InGaN/InGaN/InGaN light-emitting diodes

The light emission characteristics of blue strain-compensated InGaN/InGaN light emitting diodes (LEDs) grown on InGaN substrates were investigated using the multiband effective mass theory. The radiative recombination rate of the strain-compensated LED structure is shown to be larger than that of the conventional LED structure due to the decrease in the lattice mismatch with the substrate. Also, the light emission distribution in quantum wells (QWs) for the strain-compensated LED structure is found to be much more uniform than that for the conventional LED structure. As a result, the simulation results suggest that the efficiency droop is significantly improved when a conventional GaN barrier and substrate are replaced by an InGaN barrier and substrate. Thus, a possibility exists to employ a strain-compensated QW to improve the optical performance of InGaN-based blue LEDs.
Start and Stop Rules for Exploratory Path Analysis

This article describes a method for choosing rejection probabilities for the tests of independence that are used in constraint-based algorithms of exploratory path analysis. The method consists of generating a Markov or semi-Markov model from the equivalence class represented by a partial ancestral graph (PAG) and then testing the d-separation implications of this model using either the test proposed in Shipley (2000a), for path models without correlated errors, or by applying a Bonferonni correction for path models with correlated errors.
Monitoring Changes in Climate Extremes: A Tale of International Collaboration

| 1266 THE nATuRE of THE pRoBlEm. The Second Assessment Report (SAR) of the Intergovernmental Panel on Climate Change (IPCC), published in 1996, concluded that the available data and analyses were inadequate for any assessment to be made about the nature of global changes in extreme climate events. Since the SAR, a number of international projects have moved the focus of climate analysis from monthly to daily data so that today there is a better understanding of the extent and character of changes around the world in extreme climate events, such as heavy rainfall and heat waves. Because of the traditional focus of climatologists on monthly data and the proprietary view many countries have toward data on shorter time scales, the international exchange of long-term daily climate records has been limited, and in 1996 there was no international dataset of long-term daily terrestrial data available. Analyses of extremes were primarily limited to data from Canada, the United States, the former Soviet Union, China, and Australia. Furthermore, any analyses of extremes from these countries were hard to compare because the analyses used different measures of extremes.
Analytical field computation of a tubular permanent-magnet linear motor

This paper deals with a tubular slotless linear motor with surface-mounted permanent magnets (PMs). The magnetic field strength and flux density due to the PMs are analytically computed by applying Maxwell's equations. The field problem is solved by introducing a convenient approximation in the PM magnetization, without loss of accuracy in the final solution. The agreement of the analytical results with those obtained by the finite-element method shows the proposed field computation particularly suitable for implemention in motor design software, for a fast analysis of the PM linear motor.
Numerical study on the aerodynamic performance and safe running of high-speed trains in sandstorms

The influence of sandstorms on train aerodynamic performance and safe running was studied in response to the frequent occurrence of sandstorm weather in north China. An Eulerian two-phase model in the computational fluid dynamic (CFD) software FLUENT, validated with published data, was used to solve the gas-solid multiphase flow of a sandstorm around a train. The train aerodynamic performance under different sandstorm levels and no sand conditions was then simulated. Results showed that in sandstorm weather, the drag, lift, side forces and overturning moment increase by variable degrees. Based on a numerical analysis of aerodynamic characteristics, an equation of train stability was also derived using the theory of moment balance from the view of dynamics. A recommended speed limit of a train under different sandstorm levels was calculated based on the stability analysis.