Miracle-dz/UniFAR-FTUs huggingface dataset:
Photoelectrochemical and photosensing behaviors of hydrothermally grown ZnO nanorods

ZnO nanorods have been grown on indium-tin-oxide coated glass substrates by a low cost chemical process. Current-voltage characteristics have been studied using ZnO nanorods as photoanode in an electrochemical cell. The flat band voltage shift and depletion width of ZnO nanorods/electrolyte interface have been estimated from Mott-Schottky (MS) characteristics. The electrochemical impedance measurements have been carried out to study the charge transport mechanism at the semiconductor-electrolyte interface under dark and white light (100 mW/cm2) illumination. The doping concentration of nanorods has been extracted from MS plot. Photoresponse behavior of ZnO nanorods is found to be enhanced than seed layers with the incident of white light. Spectral dependent photovoltage of ZnO nanorods has been carried out using monochromatic light of wavelength 250–600 nm. The photopotential recovery time has been estimated for nanorods and seed layers. The stability of ZnO nanorods as a photoanode has been investigated.
Intrinsic phase shift between a spin torque oscillator and an alternating current

We report on a preferred phase shift Δϕ0 between a spin torque oscillator (STO) and an alternating current (Iac) injected at the intrinsic frequency (fSTO) of the STO. In the in-plane (IP) precession mode the STO adjusts to a state where its resistance (or voltage) lags Iac about a quarter of a wavelength [Δϕ0=(87–94)°]. In the IP mode Δϕ0 increases somewhat with the direct current. As the precession changes into the out-of-plane (OOP) mode, Δϕ0 jumps by about 180°, i.e., the STO resistance now precedes Iac about a quarter of a wavelength (Δϕ0=–86°). At the IP/OOP boundary, the alternating current mixes the two oscillation modes and both periodic and chaotic oscillations are observed. As a consequence of mixing, subharmonic terms appear in the STO signal. The intrinsic Δϕ0 will impact any circuit design based on STO technology and will, e.g., have direct consequences for phase locking in networks of serially connected STOs.
Stable Domination and Independence in Algebraically Closed Valued Fields

1. Introduction Part I. Stable Domination: 2. Some background on stability theory 3. Definition and basic properties of Stc 4. Invariant types and change of base 5. A combinatorial lemma 6. Strong codes for germs Part II. Independence in ACVF: 7. Some background on algebraically closed valued fields 8. Sequential independence 9. Growth of the stable part 10. Types orthogonal to GAMMA 11. Opacity and prime resolutions 12. Maximally complete fields and domination 13. Invariant types 14. A maximum modulus principle 15. Canonical bases and independence given by modules 16. Other Henselian fields.
Equational Classes of Distributive Pseudo-Complemented Lattices

A pseudo-complemented lattice is a lattice L with zero such that for every a ∊ L there exists a* ∊ L such that, for all x ∊ L, a ∧ x = 0 if and only if x ≦ a*. a* is called a pseudo-complement of a. It is clear that for each element a of a pseudo-complemented lattice L, a* is uniquely determined by a. Thus * can be regarded as a unary operation on L. Moreover, each pseudo-complemented lattice contains the unit, namely 0*. It follows that every pseudo-complemented lattice L can be regarded as an algebra (L; (∧, ∨, *, 0, 1)) of type (2, 2, 1, 0, 0). In this paper, we consider only distributive pseudo-complemented lattices. For simplicity, we call such a lattice a p-algebra.
Three-dimensional convection in a cubic box of fluid-saturated porous material

Calculations of finite amplitude convection in cubic boxes containing fluid-saturated porous material are reported for Rayleigh numbers R as large as 150. Steady two- or three-dimensional convection can always be forced by appropriate choice of initial conditions. Randomly chosen initial conditions will result in either two- or three-dimensional convection. Although there is a non-uniqueness associated with initial conditions which makes possible either two- or three-dimensional convection, the non-uniqueness is limited in the sense that only one two-dimensional or one three-dimensional solution appears to be realizable. Two-dimensional flows have larger Nusselt numbers than three-dimensional flows for R [lsim ] 97; the opposite is true for R [gsim ] 97.
The pre-equilibrium contribution to the (n,2n) reactions of 232Th and 238U

Cross sections of the (n,2n) reactions of 13-18 MeV neutrons with 232Th and 238U have been measured using activation techniques. The excitation functions are compared with statistical-model calculations including pre-equilibrium nucleon emission. At 18 MeV the (n,2n) reactions predominantly start prior to equilibration.
High-power high-frequency-induced Langmuir turbulence in the smooth ionosphere at Arecibo. I. Theoretical predictions for altitude-resolved plasma line radar spectra

This is the first of two papers comprising a theoretical and observational study of new, altitude-resolved, observations at Arecibo of Langmuir turbulence induced in the ionosphere by a powerful high-frequency (hf) heater operated at very low duty cycles. As shown in paper II [Cheung et al., Phys. Plasmas 8, 802 (2001)], higher power enabled the first observation at Arecibo of the well-developed decay-cascade features in the Thomson scatter radar power spectrum at the unmodified matching altitudes. New theoretical predictions are presented here for the parameters of these observations emphasizing the altitude and pump power dependence of the radar spectra and the time dependence of the spectra from the decaying spectra following heater switch-off. Further details of the strong turbulence signatures from higher altitudes are also presented. At the lower matching altitudes the increase, with hf power, of the angular width of the well-developed decay-cascade spectrum allows these spectral features to come in.
Dynamics and rupture of planar electrified liquid sheets

We investigate the stability of a thin two-dimensional liquid film when a uniform electric field is applied in a direction parallel to the initially flat bounding fluid interfaces. We consider the distinct physical effects of surface tension and electrically induced forces for an inviscid, incompressible nonconducting fluid. The film is assumed to be thin enough and the surface forces large enough that gravity can be ignored to leading order. Our aim is to analyze the nonlinear stability of the flow. We achieve this by deriving a set of nonlinear evolution equations for the local film thickness and local horizontal velocity. The equations are valid for waves which are long compared to the average film thickness and for symmetrical interfacial perturbations. The electric field effects enter nonlocally and the resulting system contains a combination of terms which are reminiscent of the Kortweg–de-Vries and the Benjamin–Ono equations. Periodic traveling waves are calculated and their behavior studied as the.
NEAR-INFRARED IMAGING AND SPECTROSCOPIC SURVEY OF THE SOUTHERN REGION OF THE YOUNG OPEN CLUSTER NGC 2264

We have obtained JHK near-IR images and JH band low-resolution spectra of candidate members of the southern region of the young open cluster NGC 2264. We have determined spectral types from H-band spectra for 54 sources, 25 of which are classified for the first time. The stars in our sample cover a large range of spectral types (A8–M8). Using a cluster distance of 780 pc, we determined a median age of 1 Myr for this region of NGC 2264, with 90% of the stars being 5 Myr or younger. To improve the statistical significance of our sample, we included 66 additional cluster members within our field of view with optical spectral classification in the literature. We derived infrared excesses using stellar properties to model the photospheric emission for each source and the extinction to correct FLAMINGOS near-IR and Spitzer mid-IR photometry, and obtained a disk fraction of 51% ± 5% for the region. Binning the stars by stellar mass, we find a disk fraction of 38% ± 9% for the 0.1–0.3 solar mass group, 55% ± 6% for 0.3–1 solar masses, and 58% ± 10% for the higher than 1 solar mass group. The lower disk fraction for the lower mass stars is similar to the results found in non-cluster regions like Taurus and Chamaeleon, but differs from the older 3 Myr cluster IC 348 in which the disk fraction is lower for the higher mass stars. This mass-dependent disk fraction is accentuated in the sample with isochrone ages younger than 2 Myr. Here, we find that 45% ± 11% of the 0.1–0.3 solar mass stars have disks, 60% ± 7% of the 0.3–1 solar mass stars have disks, and all 1–3 solar mass stars have disks. Stellar masses might be an important factor in the ability of a system to form or retain a disk early on. However, regardless of the stellar mass, the large infrared excesses expected from optically thick disks disappear within the first 2 Myr for all stars in our study and small excesses from optically thin disks are found mostly in sources younger than 4 Myr.
Six-band k⋅p calculation of the hole mobility in silicon inversion layers: Dependence on surface orientation, strain, and silicon thickness

A six-band k⋅p model has been used to study the mobility of holes in Si inversion layers for different crystal orientations, for both compressive or tensile strain applied to the channel, and for a varying thickness of the Si layer. Scattering assisted by phonons and surface roughness has been accounted for, also comparing a full anisotropic model to an approximated isotropic treatment of the matrix elements. Satisfactory qualitative (and in several cases also quantitative) agreement is found between experimental data and theoretical results for the density and temperature dependence of the mobility for (001) surfaces, as well as for the dependence of the mobility on surface orientation [for the (011) and (111) surfaces]. Both compressive and tensile strain are found to enhance the mobility, while confinement effects result in a reduced hole mobility for a Si thickness ranging from 30 to 3 nm.
Are Giant Planets Forming around HR 4796A?

We have obtained Far Ultraviolet Spectroscopic Explorer and Hubble Space Telescope STIS spectra of HR 4796A, a nearby 8 Myr old main-sequence star that possesses a dusty circumstellar disk whose inclination has been constrained from high-resolution near-infrared observations to be ~17° from edge-on. We searched for circumstellar absorption in the ground states of C II λ1036. 3, O I λ1039. 2, Zn II λ2026. 1, Lyman series H2, and CO (A-X) and failed to detect any of these species. We place upper limits on the column densities and infer upper limits on the gas masses assuming that the gas is in hydrostatic equilibrium, is well mixed, and has a temperature Tgas ~ 65 K. Our measurements suggest that this system possesses very little molecular gas. Therefore, we infer an upper limit for the gas-to-dust ratio (≤4.0) assuming that the gas is atomic. We measure less gas in this system than is required to form the envelope of Jupiter.
Spacecraft Trajectory Optimization Based on Discrete Sets of Pseudoimpulses

A brief review of new methods for continuous-thrust trajectory optimization is presented. The methods use discretization of the spacecraft trajectory on segments and sets of pseudoimpulses for each segment. Boundary conditions are presented as a linear matrix equation. A matrix inequality on the sum of the characteristic velocities for the pseudoimpulses is used to transform the problem into a large-scale linear programming form. Present-day linear programming methods use interior-point algorithms to solve such problems. In the general case, the continuous burns include a number of adjacent segments and a postprocessing of the linear programming solutions is needed to form a sequence of the burns. An optimal number of the burns is automatically determined in the postprocessing. The methods provide flexible opportunities for the trajectory computation in complex missions with various requirements and constraints. A systematic mathematical representation of these problems is considered. A summary of examples for orbit transfer, rendezvous, and moon ascent trajectories is presented. Application examples of lunar landing trajectories are examined. The examples represent a set of optimal unconstrained trajectories for different thrust-to-weight ratios and trajectories with safety descent profile, thrust level, and attitude constraints.
The Validity of the GMAT for the Prediction of Grades in Doctoral Study in Business and Management: An Empirical Bayes Approach

A validity study was conducted to examine the degree to which GMAT scores and undergraduate grade-point average (UGPA) could predict first-year average (FYA) and final grade-point average in doctoral programs in business. A variety of empirical Bayes regression models, some of which took into account possible differences in regressions across schools and cohorts, were investigated for this purpose. Indexes of model fit showed that the most parsimonious model, which did not allow for school or cohort effects, was just as useful for prediction as the more complex models. The three preadmissions measures were found to be associated with graduate school grades, though to a lesser degree than in MBA programs. The prediction achieved using UGPA alone as a predictor tended to be more accurate than that obtained using GMAT verbal (GMATV) and GMAT quantitative (GMATQ) scores together. Including all three predictors was more effective than using only UGPA. The most likely explanation for the lower levels of prediction than in MBA programs is that doctoral programs tend to be more selective. Within-school means on GMATV, GMATQ, UGPA, and FYA were higher than those found in MBA validity studies; within-school standard deviations on FYA tended to be smaller. Among these very select, academically competent doctoral students, highly accurate prediction of grades may not be possible.
Semi-Subsampled Contourlet Retrieval Algorithm Using Three Statistical Features

In order to improve the retrieval rate of contourlet transform retrieval system, a semi-subsampled contourlet transform based texture image retrieval system was proposed. In the system, the contourlet transform was constructed by non-subsampled Laplacian pyramid cascaded by critical subsampled directional filter banks, sub-bands standard deviation, absolute mean energy and kurtosis in semi-subsampled contourlet domain are cascaded to form feature vectors, and the similarity metric is Canberra distance. Experimental results on 109 brodatz texture images show that using the three cascaded features can lead to a higher retrieval rate than the combination of standard deviation and absolute mean which is most commonly used today under same dimension of feature vectors. Semi-subsampled contourlet transform based image retrieval system is superior to those of the original contourlet transform, non-subsampled contourlet system under the same system structure with same length of feature vectors, retrieval time and memory needed, decomposition structure parameters can also make significant effects on retrieval rates, especially scale number.
Efficient Bayesian Inference for Dynamic Mixture Models

Abstract A Bayesian approach is presented for estimating a mixture of linear Gaussian state-space models. Such models are used to model interventions in time series and nonparametric regression. Markov chain Monte Carlo sampling is usually necessary to obtain the posterior distributions of such mixture models, because it is difficult to obtain them analytically. The methodological contribution of the article is to derive a set of recursions for dynamic mixture models that efficiently implement a Markov chain Monte Carlo sampling scheme that converges rapidly to the posterior distribution. The methodology is illustrated by fitting an autoregressive model subject to interventions to zinc concentration in sludge.
Rotation characteristics of the Fe XIV (5303 A) solar corona

Synoptic photoelectric observations of the coronal Fe XIV line at 5303 A were analyzed to reveal the rotational behavior of the solar corona as detected in that line. A correlation analysis shows that the average synodic rotation period for a band from 30N to 30S was 27.52 days. Although the lifetimes for features in the Fe XIV corona are slightly less than those for the electron corona, overall, their rotation properties are more similar to the white-light corona than to those of active regions on the Sun with which they are generally thought to be associated. However, there appears to be a significant and time-varying component which shows differential rotation. This component appears during cycle 21 at high 7 or 60/degree/ latitudes in the late ascending phase and moves toward the equator. As the cycle progresses, the component becomes indistinguishable from faster rotating features near the equator and the effect is to produce a net differential rotation intermediate between that of the photosphere and that of the white-light corona. The observations appear to be consistent with the interpretation that the Fe XIV coronal signal arises from the effects of local heating on the large-scale density structure of the corona.
Large-Eddy Simulation of an Oscillating Cylinder in a Steady Flow

In this work, large-eddy simulation is used to study the flow around a circular cylinder undergoing streamwise sinusoidal oscillations. This benchmark case is a first step toward studying engineering applications related to flow-induced vibrations. Both the flow physics, which correlate the flow development with the time varying loading of the cylinder at two different oscillation frequencies, as well as a validation of the fluid structure interaction methodology through comparison with experimental data for the same configuration are described. With the methodology used, large-eddy simulation based on a finite volume method capable of handling moving meshes gives force predictions that generally agree well with experimentally measured data, both with respect to the overall flow development as with force magnitude.
Delay-dependent stability analysis for recurrent neural networks with time-varying delay

A global stability analysis of a particular class of recurrent neural networks with time-varying delay is performed. Both Lipschitz continuous and monotone non-decreasing activation functions are considered. Globally asymptotically delay-dependent stability criteria are derived in the form of linear matrix inequalities through the use of Leibniz–Newton formula and relaxation matrices. Finally, two numerical examples are given to illustrate the effectiveness of the given criterion.
Improved Extrapolation Technique in the Boundary Element Method to Find the Capacitances of the Unit Square and Cube

Extrapolation of the numberNof subdivisions to infinity in the boundary element method involves fitting computed results to a polynomial in 1/N. A technique of choosing the sizes of the subdivisions in such a way that the terms of lowest order in 1/Nare eliminated, giving a more accurate extrapolation, is described. The technique is used to establish the capacitances of the unit square and cube with relative errors of 3 × 10? 7and 3 × 10? 6respectively.
Conformal mapping analysis of multipactor breakdown in waveguide irises

Multipactor breakdown in a single waveguide iris is analyzed using the quasistatic approximation for the spatial distribution of the rf field in the iris. Based on the conformal mapping approach, an analytical description is given of the rf field structure in the iris. It is shown that in the central part of any iris with a length to height ratio greater than approximately 0.5, the rf field structure is close to that between two parallel plates. The multipactor threshold for the iris is determined mainly by electron losses from the central part of the iris where the losses are due to the tangential component of the emission velocity of secondary electrons. The effective length of the iris central part is determined and an estimate of the multipactor threshold for the iris is found in terms of the conventional parameters: Applied rf voltage, product of rf frequency and iris height, and iris length to height ratio. Numerical simulations are also carried out using the exact analytical description of the quasistatic rf field and taking into account a spread of electron emission velocities.
Derivation and Application of the Fokker-Planck Equation to Discrete Nonlinear Dynamic Systems Subjected to White Random Excitation

The Fokker-Planck equation is derived and applied to discrete nonlinear dynamic systems subjected to white random excitation. For the class of problems in which the nonlinearities involve only the displacements of the system, it is shown that exact solutions can be constructed for the stationary Fokker-Planck equation. It is further shown that if stationary solutions exist they are unique.
A Technical Note on the Use of Choquet Integral to Analyze Consumer Preferences: Application to Meat Consumption

This paper deals with the use of the Choquet integral to analyze meat consumer preferences. First, we present the method in comparison with multiple linear regression. Second, we illustrate the application in a data set of panelist evaluation of fresh pork loin chops for three attributes (color, lean content and overall acceptability) and purchase intention. Kappalab and Rfmtool packages for the GNU R statistical system were used for data analysis. The Choquet integral allowed to analyze the contribution of each attribute and their combinations, overcome the problems of multicollinearity in linear regression, and showed a similar or better predictive ability than linear model. In conclusion, the Choquet integral can be considered a complementary tool of usual statistical analysis of food consumer preferences. Practical Applications This paper suggests the use of the Choquet integral as a complementary statistical tool that can facilitate the analyses of complex sensory evaluations and the behavior of consumers. The Choquet integral allows estimating the importance of different sensorial attributes on the final consumer decision taking into account the dependencies existing between them. It allows a better understanding of the relationships existing between sensorial attributes especially in the presence of multicollinearity. Furthermore, the comparison of the behavior of different groups of consumers can be performed easily.
Thermal structure and dynamics of the Jovian atmosphere 1. The great red spot

Temperatures and thermal winds over the Great Red Spot (GRS) and its environs are derived from Voyager infrared spectroscopy (IRIS) data. The atmosphere over the GRS is characterized by a tropopause which is cold relative to its environment and an upper stratosphere which is relatively warm. The cold tropopause implies a decrease in anticyclonic vorticity with height above 500 mbar through the lower stratosphere. IRIS observations at 5 µm indicate little emission from the GRS itself, but enhanced emission in a ring about it, in agreement with recent ground-based results. The behavior of the tropopause and 5 µm temperatures can be consistently interpreted as resulting from a circulation which rises within the GRS and subsides in the area around it. The explanation of the upper stratospheric temperatures is not so straightforward. A previous suggestion that they may be a manifestation of the linear vertical propagation of Rossby waves appears inconsistent with the gross east-west symmetry in the stratospheric temperatures over the GRS. The implications of the present results for various theoretical models of the GRS are examined, and the possibility that latent heat release drives the GRS is discussed. Dynamical scalings based on an axisymmetric, frictionally controlled vortex suggest that, aside from the nonlinearities inherent in the parameterization of small-scale moist convection, the large-scale dynamics of the GRS are linear, as distinct from those of a tropical cyclone, which are markedly nonlinear.