Miracle-dz/UniFAR-FTUs huggingface dataset:
Subcritical convection in the presence of Soret effect within a horizontal porous enclosure heated and salted from the short sides

Purpose – The purpose of this paper is to study analytically and numerically the Soret effect on double diffusive natural convection induced in a horizontal Darcy porous layer subject to lateral heat and mass fluxes. The work focuses on the particular situation where the solutal to thermal buoyancy forces ratio, N, is related to the Soret parameter, SP, by the relation. For this particular situation, the rest state is a solution of the problem. The analytical identification of the parallel flow bifurcations counts among the objectives of the study. The effect of the governing parameters on the fluid flow properties and heat and mass transfer characteristics is also examined.Design/methodology/approach – Both the Darcy model and the Boussinesq approximation are used for the mathematical formulation of the problem. The geometry under study is a horizontal porous cavity filled with a binary fluid. The problem is solved analytically on the basis of the parallel flow approximation, valid in the case of a shall.
Rapid Synthesis and Scanning Probe Analysis of BaxSr1-xTiO3 Composition Spread Films on a Temperature Gradient Si(100) Substrate

We have succeeded in rapid optimization of dielectric properties in a combinatorial BaxSr1-xTiO3 film library fabricated on a highly insulating Si substrate. The thin-film library was prepared by using a pulsed-laser molecular beam epitaxy system equipped with a combinatorial mask for controlling compositional (i.e. x in BaxSr1-xTiO3) variations and a temperature-gradient sample holder for obtaining a growth temperature variation along the x and y axis of the substrate, respectively. The dielectric properties of this combinatorial library were mapped by a scanning evanescent microwave probe at a frequency of 2.5 GHz, revealing a strong dependence of permittivity and loss on the composition and on the growth temperature. The optimum permittivity was found in the film with x∼0.5 grown at 730°C. From X-ray diffraction analysis, strong correlation was found between the grain orientations and dielectric properties.
Optoelectronic switching in a microstructure containing Au nanoparticles

Photoconduction and nonlinear optical refraction effects exhibited by an array of separated Au microchannels are reported. The samples were constituted by Au thin solid films containing Au nanoparticles prepared by an evaporation method. The photoconductivity of the sample was measured with continuous illumination at 532 nm wavelength with 1 W average power. A vectorial two-wave interaction allowed us to explore the optical Kerr effect exhibited at 532 nm wavelength and 1 ns pulse duration. Z-scan experiments performed in a comparative Au thin solid film pointed out a saturated optical absorption as a dominant physical mechanism that originates the optical nonlinearity at 1064 nm wavelength with 150 ps pulses. The third-order optical nonlinearities measured in the studied cases with ps and ns pulses were estimated to be about = 10−10 esu. Microscopy observations were carried out to describe the morphology that is responsible for the noticeable optical Kerr effect. The optoelectronic switching behavior exhibited by the studied array was analyzed.
Simulating and Analyzing Order Book Data: The Queue-Reactive Model

Through the analysis of a dataset of ultra high frequency order book updates, we introduce a model which accommodates the empirical properties of the full order book together with the stylized facts of lower frequency financial data. To do so, we split the time interval of interest into periods in which a well chosen reference price, typically the midprice, remains constant. Within these periods, we view the limit order book as a Markov queuing system. Indeed, we assume that the intensities of the order flows only depend on the current state of the order book. We establish the limiting behavior of this model and estimate its parameters from market data. Then, to design a relevant model for the whole period of interest, we use a stochastic mechanism that allows to switch from one period of constant reference price to another. Beyond enabling to reproduce accurately the behavior of market data, we show that our framework can be very useful for practitioners, notably as a market simulator or as a tool for the transaction cost analysis of complex trading algorithms.
Short light pulse amplification and compression by stimulated Brillouin scattering in plasmas in the strong coupling regime

Short light pulse amplification using the stimulated Brillouin backscattering mechanism is considered. The novel feature is that the interaction process takes place in the strongly coupled regime and therefore the pulse compression is not limited by the ion-acoustic wave period. The mechanism is very efficient due to the large ratio of light frequency to the characteristic ion-acoustic wave frequency. Although large-amplitude ion-acoustic waves are generated and subsequent wave breaking takes place, the fluid and kinetic nonlinearities do not intervene with the amplification itself.
Vibrio cholerae 0139 in Thailand in 1994

Three different hospitals in Thailand that were surveyed included: Samutsakorn hospital, a provincial hospital 30 kilometres to the west of Bangkok; Children's Hospital in Bangkok; and Suan Phung hospital, a small district hospital on the Thai-Burmese border. All patients with watery diarrhoea, either in-patients or out-patients, that were seen Monday through Friday, were cultured for Vibrio cholerae. Stools or rectal swabs collected from patients with diarrhoea were cultured on thiosulfate-citrate-bile-salts sucrose agar (Eiken Ltd, Tokyo, Japan) before and after inoculation in alkaline peptone water, pH 8-0. Isolates were identified as V. cholerae using criteria described by Sakazaki [4]. V. cholerae isolates were tested for agglutination in polyvalent 01 and monospecific Ogawa, Inaba, and 0139 antisera. V. cholerae isolates were tested for DNA sequences encoding cholera toxin (ctx) [5]. Colony hybridization assays were performed on Whatman 541 filters as described by Maas [6]. Pre-hybridization and hybridization reactions were performed under stringent hybridization conditions in 50 % formamide, 2 x Denhardt's solution
InSb working standard radiometers

InSb radiometers have been developed and characterized for use as transfer standards at the National Institute of Standards and Technology (NIST). The InSb radiometers will hold a portion of the recently realized infrared spectral response scale of the NIST and will serve as working standards for the calibration of test detectors. These radiometers will measure radiant power or irradiance from 2 µm to 5.4 µm. They have a 17° field-of-view. The InSb detectors were selected for high shunt impedance to achieve high sensitivity. The transimpedance-gain, voltage-gain, and loop-gain of the current-to-voltage converters were optimized for optical radiation chopped at 40 Hz. At the peak response, the noise-equivalent-power is 0.6 pW in an electrical bandwidth of 0.3 Hz. The ratio of the dc ambient-background current to the ac noise-equivalent current is 107. Spatial and angular responsivities, linearity, stability, and flashing were also characterized.
Oxygen-enhanced models for globular cluster stars. I: Evolutionary tracks

Evolutionary tracks for 13-16 mass values (depending on the assumed chemical composition) in the range 0.15 ≤ M/M ⊙ ≤ 1.25 have been computed for each of 10 metallicities between [Fe/H] = -2.26 and [Fe/H] = -0.47. The helium content was assumed to vary from Y = 0.2350 to 0.2454 over this range in [Fe/H]. Oxygen overabundances were chosen to obey [O/Fe] = -0.5 [Fe/H], for [Fe/H] ≥ -1.0, and [O/Fe] = -0.2 [Fe/H] + 0.3, for lower iron abundances, based on an analysis of field star data. Solar number abundance ratios were adopted for all of the other heavy elements
Vorticity Budget for AMEX. Part II: Simulations of Monsoon Onset, Midtropospheric Lows, and Tropical Cyclone Behavior

Abstract Diagnostics from the observational dataset of the Australian Monsoon Experiment (AMEX) have revealed two interesting characteristics of convective systems over the Australian Tropics (Part I of this study). The first is a midlevel convergence maximum in situations of disorganized convection, which implies weak low-level and strong upper-level convective heating. The second is the presence of large apparent vorticity sources during deep convective and stratiform events. It is suggested that these characteristics are related to the ascent and descent motions in tropical cloud systems and to the way in which they redistribute mass and the background vorticity. To investigate the importance of these features of convection on tropical prediction, a representation of the observed thermodynamic and kinematic effects of clouds has been implemented in the Bureau of Meteorology Research Centre's tropical limited-area model. To represent the observed structure of convective heating in numerical simulation e.
Bayesian Estimation of the Two-Parameter Gamma Distribution

ABSTRACT A Bayesian estimation of the two-parameter gamma distribution is considered under the non informative prior. The Bayesian estimator is obtained by Gibbs sampling. The generation of the shape parameter in the Gibbs sampler is implemented using the adaptive rejection sampling method of Gilks and Wild (1992). Finally, the results of our numerical studies show that the Bayesian estimator using Gibbs sampling along with adaptive rejection sampling outperforms the maximum likelihood and moment based estimators, as well as the other Bayesian estimator.
Nonlinear extension of the x-ray diffraction enhanced imaging

Diffraction enhanced imaging is the analyzer-based x-ray imaging technique which allows extraction of the refraction and absorption contrasts from two images taken on the opposite sides of the rocking curve of the analyzer. It is widely used in different fields of science. However, the information provided by the method is qualitative rather than quantitative. This happens because either side of the rocking curve is approximated as a line. One can overcome this problem of considering the rocking curve instead of the approximation. This letter is dedicated to the implementation of this idea and includes theoretical background and experimental validation.
Coherence Time of Rabi Oscillations of Cold Atoms

Ultracold atoms, also described as “matter waves”, stand at the base of two Nobel prizes in the last 15 years. During the same time, two other Nobel prizes were given for quantum optics. The techniques related to these four Nobel prizes are now used as building blocks for technologies such as atomic clocks, acceleration sensors for navigation, magnetic sensors, gravitational sensors, quantum communication and quantum computers. The main purpose of this thesis is to examine both experimentally and theoretically the effect of thermal motion (the temperature of the cloud of atoms) and the gradient of the driving field on the coherence time of Rabi oscillations. In order to increase the temperature range under examination, we improved our experimental set-up to achieve laser cooling beyond the Doppler limit, down to 3 μK. We then developed a theoretical model predicting the coherence time of Rabi oscillations in the presence of an inhomogeneous driving field. Finally, we demonstrated the validity of the model by an experiment measuring the coherence time as a function of temperature.
Compact Dual-Band Branch-Line Coupler with 20 : 1 Power Dividing Ratio

This paper presents a compact structure of dual-band branch-line coupler with 20 : 1 power dividing ratio. To obtain dual-band operation and high-ratio power division, branch lines with center-tapped short and open stubs are discussed and employed to replace the high and low impedance quarter-wavelength lines in the conventional unequal branch-line coupler respectively. As an example, a 20 : 1 branch-line coupler operating at 1.0 GHz and 1.8 GHz is designed, fabricated and measured. The measurements are in good agreement with the simulations. It is shown that the dual-band branch-line coupler is suitable for high-ratio power division with small frequency ratio.
A Review on the Reproduction and Development in Fish

In order that survival of young be more than optimum, the timing of spawning by the mature adult fish is so adjusted that must be closely linked to the availability of maximum congenial environment added by increased food availability of food for the newly hatched young ones. The availability of food for the larvae and juveniles of most temperate and cold water fish species varies on a seasonal basis and following this fish are usually found to have a discrete and selective spawning season so perfectly timed that hatched out larvae will get readily available exogenous food from nature for their further development. Thus, in many temperate and cold water species, spawning is an annual event. Spawning culminates a series of preparatory events during which the gametes develop and the gonads increase in size. The annual cycle of fishesgenerally categorized into three major phases:
Multiwavelength study of the nuclei of a volume-limited sample of galaxies – II. Optical, infrared and radio observations

We present optical and infrared broad-band images, radio maps, and optical spectroscopy for the nuclear region of a sample of nearby galaxies. The galaxies have been drawn from a complete volume-limited sample for which we have already presented X-ray imaging. We modelled the stellar component of the spectroscopic observations to determine the star formation history of our targets. Diagnostic diagrams were used to classify the emission-line spectra and determine the ionizing mechanism driving the nuclear regions. All those sources classified as active galactic nuclei present small Eddington ratios (∼10 -3 -10 -6 ), implying a very slow growth rate of their black holes. We finally investigate the relative numbers of active and normal nuclei as a function of host galaxy luminosity and find that the fraction of active galaxies slowly rises as a function of host absolute magnitude in the M B ∼ -12 to -22 range.
Advanced fibres for soliton systems

The technology for length-varying fibre drawing from standard preforms has been worked out. It allows fibres with the necessary length dependence of the chromatic dispersion to be fabricated. Fibres with varying dispersion can have a lot of applications in soliton propagation control. Such fibres allow one to realize both the regime of effective amplification and the effective compression of optical solitons. This technology is based on a digital control system and can be used in the conditions of a standard drawing installation.
Dimensional Reduction for Latent Scores Modeling Using Recursive Integration

This article addresses the problem of estimating the cutpoints that are used to model ordinal categorical data from continuous latent variables. A Bayesian approach is taken, and the cutpoint estimates are obtained as the expectation of their posterior distribution. Ostensibly this involves a high-dimensional integral evaluation with the dimension equivalent to the number of cutpoints. However, it shows how recursive integration techniques can be used to reduce the calculation to a series of two-dimensional integral evaluations, resulting in a practical estimation algorithm whose computational complexity is only a linear function of the number of cutpoints. Observed covariates can also be incorporated into the model, and the efficient estimation of the cutpoints assists in the estimation of other parameters. The new methodology is illustrated with an application to credit risk rating modeling of Thai corporations, and the computational advantages over other standard approaches are demonstrated.
Partial inverse problems

We develop consequences of the generalization of ‘ordinary’ to ‘partial’ inverse problems—where the latter are inverse problems in which the unknown has domain dimension higher than 1 and is thereby subject to operators whose components individually do not address all the variables. This is analogous to the transition from ordinary to partial differential equations—the difference in this case being that the relevant operators are compact rather than unbounded. Accordingly, the significance of this generalization is in its implications for regularization technique. Previously, such problems (which arise in widespread scientific settings) have been approached with a variety of ad hoc methodologies. In contrast, we derive a favoured methodology based on the changes in group structures naturally associated with actions on vectors (the unknowns in discretized ordinary inverse problems) versus those associated with actions on higher order arrays (the unknowns in discretized partial inverse problems). A principal finding of this approach is that the set of admissible random matrices for treatment of a discretized partial inverse problem is a particular homogeneous space whose isotropy group determines the favoured estimation mechanism. A number of surprising results are obtained, including identification of situations where a favoured nontrivial regularization matrix can be entirely determined from treatment of (discretized) second kind Fredholm equations. The derived methodology is contrasted with various standard treatments. Numerical examples illustrate the method and demonstrate its potential for providing improved accuracy compared with usual regularization technique.
Field-current phase diagrams of in-plane spin transfer torque memory cells with low effective magnetization storage layers

Field-current phase diagrams were measured on in-plane anisotropy Co60Fe20B20 magnetic tunnel junctions to obtain the spin transfer torque (STT) field-current switching window. These measurements were used to characterise junctions with varying free layer thicknesses from 2.5 down to 1.1 nm having a reduced effective demagnetizing field due to the perpendicular magnetic anisotropy at CoFeB/MgO interface. Diagrams were obtained with 100 ns current pulses, of either same or alternating polarity. When consecutive pulses have the same polarity, it is possible to realize the STT switching even for conditions having a low switching probability. This was evidenced in diagrams with consecutive pulses of alternating polarity, with 100% switching obtained at 4.7 MA/cm2, compared to the lower 3.4 MA/cm2 value for same polarity pulses. Although the low level of the current density window is higher in alternating polarity diagrams, the field window in both diagrams is the same and therefore independent of the pulse po.
Electromagnetic volume scattering in the half-space: a moment-method analysis without Sommerfeld integrals or their approximations

Abstract Traditionally, in moment-method analyses of electromagnetic scattering, the elements of the impedance matrix are calculated as convolutions of the basis elements with the appropriate dyadic Green's function. However, for scattering in the half-space, the vertical and azimuthal copolar terms of the Green's function require evaluation of Sommerfeld integrals which are computationally burdensome. In this paper, it is shown that, in populating the impedance matrix for the half-space problem, evaluation of Sommerfeld integrals is, in fact, not necessary. For monochromatic excitation, the plane-wave expansion of the scattered field constitutes a Fourier transform, in the horizontal plane, of a vector spectral function. This vector function results from the convolution, in the vertical dimension, of the respective angular spectra of the Green's function and the equivalent current. On application of the moment method, through the Weyl identity, the impedance-matrix elements corresponding to the singular terms of the Green's function are convolutions in the horizontal plane of spherical potentials, and Fourier transforms of scalar spectral functions. These scalar functions are derived from the basis elements and, with a judicious choice of basis, they are well behaved and of compact support, and consequently their Fourier transforms can be computed as FFTs.
Shear in Steel Beam-to-Column Connections The current AISC design formula is shown to be conservative by theoretical analysis and tests of a full size beam-to-column connection subjected to moment , shear and high axial loads

—The condition of high shear stress in rigid frame connections and the effect of high axial force is investigated. A yield condition is derived and verified by a test. After yielding in the test specimen, stable joint deformation was observed under monotonic loading and the connection carried 2.75 times what is considered to be the yield strength in shear. The current AISC design formula is shown to be conservative.
The photodissociation of CO in circumstellar envelopes

The CO photodissociation rate for the unshielded ISM is calculated using recent laboratory results which confirm that photodissociation occurs by way of line absorption. A value of 2.0 x 10 to the -10th/s, an order of magnitude higher than the rate used in the past, is obtained. The new rate and a treatment of the radiative transfer and shielding are used to develop a theory for the CO abundance in the circumstellar envelopes of cool, evolved stars, and results are presented on the spatial variation of CO, C, and C(+). It is shown that these distributions play important roles in determining the observational properties of circumstellar envelopes. 29 references.
A Study of H2 Emission in the Bipolar Proto-Planetary Nebula IRAS 17150–3224

H2 emission has been detected in the bipolar proto-planetary nebula IRAS 17150-3224 from the 1-0 S(1), 1-0 S(0), and 2-1 S(1) transitions in the 2 μm region. Line ratios suggest that this emission is due to collisional excitation. High-resolution imaging with NICMOS on HST shows that the emission comes from four regions: clumps near the ends of the lobes (the brightest region), the lobes in general, a particular region outside the northwest lobe, and a faint loop in the equatorial region. Spatially resolved high-resolution spectra at 2.12 μm reveal that the H2 1-0 S(1) line has a velocity width of about 35 km s-1 in the lobes, consistent with C-type shocks. The emission from the clumps in the lobes appears to arise from the impact of a fast wind with the slower moving material in the AGB wind.
The challenges of optically designing roadway lighting

New concerns regarding the unwanted effects of lighting our nighttime environment (i.e., light pollution), and new efforts to design energy efficient roadway lighting installations, are changing the requirements of roadway lighting. These factors necessitate the need for different luminous intensity distributions with greater optical control than have traditionally been produced by roadway lighting fixtures. New requirements affecting the optical design of roadway lighting are presented. An example of a nonimaging optical design solution that addresses these requirements is given. Conclusions are then made about the challenges that lie ahead in the optical design of roadway lighting fixtures.
Momentum Distribution Function of the One-Dimensional Hubbard Model–An Analytical Approach

We calculate the behaviour of the momentum distribution function n(k) for the ground state of the one-dimensional Hubbard model with arbitrary band filling in the weak-coupling regime. For the incommensurate case and U > 0 we derive the variation of n(k) in the vicinity of the Fermi wave vector kF and find a power law behaviour with a maximum exponent of one instead of a discontinuous jump. We also make a comparison with the n(k) obtained from recent Monte Carlo simulations and conclude that these numerical results are still seriously affected by finite-size effects. We finally consider the half-filled band and find a linear variation of n(k) close to kF, the scale being set by the charge gap of the Hubbard model.