Miracle-dz/UniFAR-FTUs huggingface dataset:
Aerodynamics Study of Flow Past Two Tandem Bluff Bodies at Low Reynolds Number

Aerodynamics of flow past two tandem bluff bodies is a critical problem in fluid mechanics. In this work, the flow over two circular cylinders with unequal diameters in tandem arrangement is numerical investigated using lattice Boltzmann method. The diameter of the bigger one is adopted as the characteristic length, the diameter ratio is fixed as 2, and the Reynolds number is 100. Spacing between two cylinders (scaled by the characteristic length) are varied from 0 to 3 characteristic diameter, and the effects of which on the flow patterns of such a system are studied. The results show that flow patterns behind two tandem unequal circular cylinders are significantly different from that behind a single one. Due to the downstream cylinder, two classic vortex interaction modes are observed, known as destruction interaction mode and construction mode.
Stress-based binary differential evolution for topology optimization of structures

Abstract Differential evolution (DE) is a heuristic optimization method used to solve many optimization problems in real-value search space. It has the advantage of incorporating a relatively simple and efficient form of mutation and crossover. However, the operator of DE is based on floating-point representation only, and is difficult to use in solving combinatorial optimization problems. In this article, a modified binary DE is developed using binary bit-string frameworks with a logical operation binary mutation mechanism. Further, a new stress-based binary mutation mechanism is also proposed to drive the binary DE search towards the optimal topology of the structure with higher performance and fewer objective function evaluations. The numerical results show that the performance of the proposed algorithm using stress-based binary mutation has high capability and efficiency in topology optimization of the structure.
Coulomb blockade-based nanothermometry in strong magnetic fields

We have performed experiments to test for the susceptibility to strong magnetic fields of electron tunneling in normal metal -based nanostructures for Coulomb blockade primary thermometry. We have confirmed that, to within our accuracy of about ±1%, the single electron charging -induced zero bias differential resistance maximum is unaffected by the field up to 23 T at temperatures of 0.4–4.2 K. We discuss the simple theoretical basis of this immunity. We also report on the practical limitation at low temperatures imposed by superconductivity of aluminium in small magnetic fields.
PLANETARY TRANSITS WITH THE ATACAMA LARGE MILLIMETER/SUBMILLIMETER ARRAY RADIO INTERFEROMETER

Planetary transits are commonly observed at visible wavelengths. Here we investigate the shape of a planetary transit observed at radio wavelengths. Solar maps at 17 GHz are used as a proxy for the stellar eclipse by several sizes of planets from super-Earths to hot Jupiters. The relative depth at mid-transit is the same as observed at visible wavelengths, but the limb brightening of the stellar disk at 17 GHz is clearly seen in the shape of the transit light curve. Moreover, when the planet occults an active region the depth of the transit decreases even further, depending on the brightness of the active region relative to the surrounding disk. For intense active region, with 50 times the brightness temperature of the surrounding disk, the decrease can supercede the unperturbed transit depth depending on the size of the eclipsing planet. For a super-Earth (Rp = 0.02 Rs) crossing, the decrease in intensity is 0.04%, increasing to 0.86% in the case when a strong active region is present. On the other hand, for a hot Jupiter with Rp = 0.17Rs, the unperturbed transit depth is 3% increasing to 4.7% when covering this strong active region. This kind of behavior can be verified with observation of planetary transits with the Atacama Large Millimeter/submillimeter Array radio interferometer.
Video retargeting for stereoscopic content under 3D viewing constraints

The imminent deployment of new devices such as TV, tablet, smart phone supporting stereoscopic display creates a need for retargeting the content. New devices bring their own aspect ratio and potential small screen size. Aspect ratio conversion becomes mandatory and an automatic solution will be of high value especially if it maximizes the visual comfort. Some issues inherent to 3D domain are considered in this paper: no vertical disparity, no object having negative disparity (outward perception) on the border of the cropping window. A visual attention model is applied on each view and provides saliency maps with most attractive pixels. Dedicated 3D retargeting correlates the 2D attention maps for each view as well as additional computed information to ensure the best cropping window. Specific constraints induced by 3D experience influence the retargeted window through the map computation presenting objects that should not be cropped. The comparison with original content of 2:35 ratio having black stripes provide limited 3D experience on TV screen, while the automatic cropping and exploitation of full screen show more immersive experience. The proposed system is fully automatic, ensures a good final quality without missing fundamental parts for the global understanding of the scene. Eye-tracking data recorded on stereoscopic content have been confronted to retargeted window in order to ensure that the most attractive areas are inside the final video.
The hard X-ray luminosity function from ASCA surveys

We summarize the nature of hard X-ray populations at “bright” fluxes > 10–13 erg cm–2 s–1 (2–10 keV) from optical identification of ASCA surveys, and present results of the hard X-ray luminosity function (HXLF) of Active Galactic Nuclei (AGN). Combined with HEAO1 and Chandra surveys we construct a hard-band selected sample with extremely high degree of completeness (>95%), consisting of 228 AGNs over the flux range 10–11 ≈ 3 × 10–15 erg cm–2 s–1 (2–10 keV). We find evidence that the percentage of “type-II” AGNs decreases with the intrinsic luminosity. The intrinsic HXLF of the whole AGNs (including type-II AGNs) is well described with the pure luminosity evolution (PLE) model up to redshift of 3. Our results directly constrain the evolution of AGNs that produce a major part of the hard X-ray background.
Hardness and elastic properties of covalent/ionic solid solutions from first-principles theory

Most of the engineering materials are alloys (solid solutions) and inevitably contain some impurities or defects such as vacancies. However, theoretical predictions of the hardness of this kind of materials have rarely been addressed in literature. In this paper, a hardness formula for multicomponent covalent solid solution is proposed based on the work of Simůnek and Vackař [Phys. Rev. Lett. 96, 085501 (2006)]. With this formula, the composition dependence of the hardness is investigated for titanium nitrogencarbide (TiN1−xCx), off-stoichiometric transition-metal nitrides (TiN1−x and VN1−x), and B-doped semiconductors. The predicted hardness is in good agreement with experiments. To investigate the most frequently quoted correlation between hardness and elastic modulus, the elastic moduli of the systems involved in this paper have also been calculated. The results show that the elastic moduli cannot be used for rigorous predictions of the hardness of the solid solutions.
Consensus Forecasts of Modeled Wave Parameters

Abstract The use of numerical guidance has become integral to the process of modern weather forecasting. Using various techniques, postprocessing of numerical model output has been shown to mitigate some of the deficiencies of these models, producing more accurate forecasts. The operational consensus forecast scheme uses past performance to bias-correct and combine numerical forecasts to produce an improved forecast at locations where recent observations are available. This technique was applied to forecasts of significant wave height (Hs), peak period (Tp), and 10-m wind speed (U10) from 10 numerical wave models, at 14 buoy sites located around North America. Results show the best forecast is achieved with a weighted average of bias-corrected components for both Hs and Tp, while a weighted average of linear-corrected components gives the best results for U10. For 24-h forecasts, improvements of 36%, 47%, and 31%, in root-mean-square-error values over the mean raw model components are achieved, or 14%, 22.
Analysis of spatial domain multiplexing/space division multiplexing (SDM) based hybrid architectures operating in tandem with wavelength division multiplexing

Spatial domain multiplexing (SDM) also known as space division multiplexing adds a new degree of photon freedom to existing optical fiber multiplexing techniques by allocating separate radial locations to different MIMO channels as a function of the input launch angle. These independent MIMO channels remain confined to the designated location while traversing the length of the carrier fiber, due to helical propagation of light inside the fiber core. The SDM technique can be used in tandem with other multiplexing techniques, such as time division multiplexing (TDM), and wavelength division multiplexing in hybrid optical communication schemes, to achieve higher optical fiber bandwidth by increasing the photon efficiency due to added degrees of photon freedom. This paper presents the feasibility of a novel hybrid optical fiber communications architecture and shows that SDM channels of different operating wavelengths continue to follow the input launch angle based radial distribution pattern.
Fresnel zone-plate based X-ray microscopy in Zernike phase contrast with sub-50 nm resolution at NSRL

A transmission X-ray microscope using Fresnel zone-plates (FZPs) has been installed at U7A beamline of National Synchrotron Radiation Laboratory (NSRL). The objective FZP with 45 nm outermost zone width delivers a sub-50 nm resolution. A gold phase ring with 2.5 μm thickness and 4 μm width was placed at the focal plane of the objective FZP at 8 keV to produce a negative Zernike phase contrast. A series of samples were used to test the performance of the Zernike phase contrast X-ray microscopy.
Spatial transformation of sound fields

In this paper it will be demonstrated how cross spectra measured by a modified 1/3 octave realtime intensity analyzer during a planar scan can be used to predict pressure, particle velocity, and intensity in a half‐space not containing the source of the (noise) field. We just have to assume a rather limited number of significant uncorrelated components in the total source. In the nearfield region on both sides of the scan plane the field quantities are evaluated using a nearfield holography technique similar to the technique described by Williams, Maynard, and Skudrzyk [J. Acoust. Soc. Am. 68, 340–344 (1980)] for analysis of coherent sound fields. Outside the nearfield region Helmholtz' integral equation is used for the prediction. The combined method allows various simulations to be carried through. For example we can estimate a planar source distribution by means of the holography method, simulate an attenuation of some part of the source, and investigate the effect of this attenuation on the field in t.
Convergence of a Force‐Based Hybrid Method in Three Dimensions

We study a force‐based hybrid method that couples an atomistic model with the Cauchy‐Born elasticity model. We show that the proposed scheme converges to the solution of the atomistic model with second‐order accuracy, since the ratio between lattice parameter and the characteristic length scale of the deformation tends to 0. Convergence is established for the three‐dimensional system without defects, with general finite‐range atomistic potential and simple lattice structure. The proof is based on consistency and stability analysis. General tools for stability analysis are developed in the framework opseudodifference operators in arbitrary dimensions. © 2012 Wiley Periodicals, Inc.
DETECTION OF GROSS ERRORS IN NONLINEARLY CONSTRAINED DATA: A CASE STUDY

The MIMT algorithm previously developed for gross error detection in linearly constrained systems was extended to nonlinear systems. The algorithm was tested by means of computer simulation using data from an industrial grinding circuit. The overall performance of the algorithm on the nonlinear system was found to be comparable to that exhibited on a linear system of approximately the same size. The algorithm correctly detected approximately 80% of all systematic errors in the data and achieved an average reduction in total error of more than 60%. The detection rate for the more significant (gross) systematic errors was approximately 90%. These results represent the first detailed performance evaluation of a gross error detection algorithm applied to a nonlinear system of industrial significance.
Preliminary results on the study of the environment of a complete sample of Seyfert galaxies

The results of the study of the environment of a complete sample of Seyfert galaxies taken from the CfA Redshift Survey (Davis et al. 1983; Huchra et al. 1983) are shown. In particular we compare the distribution of the positions of all galaxies located within five diameters from each Seyfert galaxy of our sample with the angalogous distribution observed in a control sample of normal galaxies taken from the Merged Catalogue of Galaxies (hereafter MERCG) (Kogoshvili 1986). This research is based on the analysis of the digitized images of the “Digitized Sky Survey” and on the on-line catalogues APM (Automatic Plate Measuring System) and APS (Automated Plate Scanner).
Mathematical model of an electromechanical actuator using flux state variables applied to reluctance motor

– Aims to present a new approach for formulating state‐space equations of an electromechanical actuator using magnetic flux linkages as state variables. , – The model is based on employment of discrete databases and their interpolation. The algorithm of determination of databases defining the flux/current characteristics of an actuator is described. Graphical interpretation of variable transformation is presented. A simplified, two‐axis model of reluctance motor is used to illustrate the application of the proposed modelling technique. Comparison with the classical model of the motor is used to verify the validity of the method. Analysis is focused on determination of saturation phenomenon influence on formulation methodology and on correctness of obtained results. , – A very good agreement is observed between reference dq model and the proposed model. The main problem of the presented method is the existence of undefined entries in databases. Sufficiently dense databases can be used to overcome the problem. , – The model is limited to actuators in which eddy currents and hysteresis phenomenon can be neglected. Future research will be concentrated on evaluation of different interpolation strategies of databases used in the model for realistic saturation conditions. , – The model can be used as a library block for testing various control strategies for actuators without standard simplifying assumptions (e.g. sinusoidal winding distribution). It can be implemented in any simulational software (e.g. SIMULINK) as its block diagram is simple and no numerical differentiation is necessary in derivation of the model data. , – Presents an extension of state‐space model of an actuator based on database discretised description of variables to two or more state variables.
Transparent and flexible nonvolatile memory using poly(methylsilsesquioxane) dielectric embedded with cadmium selenide quantum dots

In this work, a transparent and flexible nonvolatile memory was fabricated using a solution process. The conduction mechanisms of the metal/insulator/metal structure consisting of cadmium selenide quantum dots embedded in poly(methylsilsesquioxane) dielectric layers were investigated in terms of current–voltage characteristics. The memory device is reprogrammable and stable up to 1 × 104 s with little deterioration and a distinct ON/OFF ratio of 104. Endurance cycle and retention tests of the as-fabricated memory device were also carried out. The results indicate that the device has good operating stability.
A Surface-Integral Formulation for Jet Noise Prediction Based on the Pressure Signal Alone

While large-scale simulation of jet noise is the most thorough technique currently available for jet noise prediction, three-dimensional direct computation of both the near and far field requires prohibitive computational capability. In this work we propose to limit large-scale simulation to the near field to provide the pressure distribution over a cylindrical surface surrounding the jet. A surface-integral formulation is presented herein in which the calculated pressure on the cylindrical surface is used to obtain the far-field sound, without the need for the normal derivative of the pressure. The results are compared to that of direct large-scale simulation and to the zonal approach in which linearized Euler equations are used as an extension tool.
Culturally Adapted Social, Emotional, and Behavioral Support for Black Male Learners

Black learners, like all other learners, bring their cultural values into the classroom, how they express themselves, and how they problem-solve. In addition, their life experiences influence their social and emotional behaviors. This study examined the effects of a multicomponent intervention approach—including a culturally adapted social and emotional learning curriculum, check-in/check-out, and self-monitoring—on the externalizing behaviors of Black male learners in an urban elementary school. A multiple-baseline-across-classes, single-case, experimental design evaluated the effects of the intervention package. Results from the study show a consistent decrease in externalizing problem behaviors, increases in social and emotional competencies, and high levels of social validity for the intervention package based on the input of relevant stakeholders. An embedded alternating-treatment, single-case design explored the relative impact of self-monitoring. The authors also include a discussion of the limitations of this work and the implications for future research.
Negative-donor centers and absorption spectra of quantum dots

Negative-donor centers in quantum dots with parabolic confinement potential have been studied for the case with the presence of a perpendicular magnetic field. Calculations are carried out by using the method of numerical diagonalization of the Hamiltonian matrix within the effective-mass approximation. The ground-state electron structures and angular momentum transitions are investigated. The binding energies of the ground and some bound excited states are obtained as a function of the applied magnetic field strength. As the magnetic field strength B is increased, there may appear more bound states. On the basis of the computed energies and wavefunctions, the linear optical absorption coefficients have been examined, for between the 1P and 1S states. The results are presented as a function of the incident photon energy for the different values of the confinement strength and the magnetic field strength. It is found that the optical properties of the negative-donor centers in quantum dots are strongly affected by the confinement strength and the magnetic field strength.
New findings regarding parameter estimation in the Gauss-Markov model with restrictions on coefficients

Abstract When addressing the issue of parameter estimation within a Gauss-Markov framework with linear constraints, several approaches are considered which turn out to hinge the solution of the problem on the inversion of an ad hoc bordered matrix. Within this connection, in the wake of a recent author’s result (Faliva and Zoia [3]), elegant partitioned inversion formulae — with projection operators as entries — are obtained, which lead to find informative closed-form expressions for the parameter estimator without collinearity qualification. This offers, on the one hand, enlightening solutions to the estimation problem, which covers Theil’s formula as a special case, and on the other, paves the way to gaining a deeper insight into linear estimator structure.
Investigating Lexical NP-Chunking with Universal Dependencies for Portuguese

A tarefa de análise superficial consiste em recuperar uma quantidade limitada de informações sintáticas de frases escritas em linguagem natural. Este trabalho tem como objetivo identificar e extrair um tipo particular de sintagma nominal denominado sintagma nominal lexical (SNL). Os estudos iniciais mostrados neste artigo demostram, em primeira mão, a possibilidade de identificar e extrair SNL a partir de sentenças escritas em português e anotadas pelo formalismo da Universal Dependency. Também demonstramos como a tarefa de análise sintática superficial pode se beneficiar das marcações de PoS usando um comitê de algoritmos de aprendizado de máquina.
Study on a Rapid Real-Time Feature Extraction Algorithm

A fast feature extraction algorithm is presented in this paper based on the color and point feature, With the aim of required feature points, the location of the object includes object region detection and feature point location. The area of object detection is used to look for the centre of gravity point from the scaling image. The feature point location is based on the object region detection, cuts a picture from the image, and extracts speeded up robust feature (SURF) points of the target within the cut picture. The target position is calculated according to the value of the feature points, it provides a basis for object tracking. The experimental results verify the effectiveness of the proposed method.
Development of a Numerical Tool for Foil Acceleration by an Intense Pulsed Ion Beam

When we irradiate a foil with an intense pulsed ion beam, ablation plasma is created, and the foil is accelerated. In this study, we developed a numerical model of this phenomenon. We analyze the temperature and pressure of the ablation plasma, and the velocity of the accelerated foil by numerical simulation. It was possible for us to analyze the behavior and detailed results of the ablation plasma expansion and acceleration of the foil. We could also observe the processes of ablation plasma expansion and foil acceleration by back-lighting high-speed photography. The numerical results of foil velocity agree well with the experimental ones over a wide range of energy density values of an ion beam. We analyzed the time trend of the foil velocity, and we could observe that the foil is rapidly accelerated immediately after a delay.