Miracle-dz/UniFAR-FTUs huggingface dataset:
Community centrality for node's influential ranking in complex network

Some tiny party of influential nodes may highly affect spread of information in complex networks. For the case of very high time complexity in the shortest path computation of global centralities, making use of local community centrality to identify influential nodes is an open and possible problem. Compared to degree and local centralities, a five-heartbeat forward community centrality is proposed in this paper, in which a five-step induced sub-graph of certain node in the network will be achieved. Next, we induce the minimal spanning tree (MMT) of the sub-graph. Finally, we take the sum of all weights of the MMT as community centrality measurement that needs to be the influential ranking of the node. We use the susceptible, infected and recovered (SIR) model to evaluate the performance of this method on several public test network data and explore the forward steps of community centrality by experiments. Simulative results show that our method with five steps can identify the influential ranking of nodes in complex network as well.
Time response analysis of fractional-order control systems: A survey on recent results

The aim of this paper is to provide a survey on the recently obtained results which are useful in time response analysis of fractional-order control systems. In this survey, at first some results on error signal analysis in fractional-order control systems are presented. Then, some previously obtained results which are helpful for system output analysis in fractional-order control systems are summarized. In addition, some results on the analysis of the control signal and the system response to the load disturbances in fractional-order control systems are reviewed.
IBIS: The Imager on-board INTEGRAL

The IBIS telescope is the high angular resolution gamma-ray imager on-board the INTEGRAL Observatory, suc- cessfully launched from Baikonur (Kazakhstan) the 17th of October 2002. This medium size ESA project, planned for a 2 year mission with possible extension to 5, is devoted to the observation of the gamma-ray sky in the energy range from 3 keV to 10 MeV (Winkler 2001). The IBIS imaging system is based on two independent solid state detector arrays optimised for low (15 1000 keV) and high (0:175 10:0 MeV) energies surrounded by an active VETO System. This high eciency shield is essential to minimise the background induced by high energy particles in the highly excentric out of van Allen belt orbit. A Tungsten Coded Aperture Mask, 16 mm thick and1 squared meter in dimension is the imaging device. The IBIS telescope will serve the scientific community at large providing a unique combination of unprecedented high energy wide field imaging capability coupled with broad band spectroscopy and high resolution timing over the energy range from X to gamma rays. To date the IBIS telescope is working nominally in orbit since more than 9 month.
A novel neutron multiplicity detector using lithium fluoride and zinc sulphide scintillator

Efficient neutron counters have been constructed using large area layers of a mixture of lithium fluoride and zinc sulphide, the scintillation light being transmitted to photomultipliers by wavelength shifting light guides. An array of these counters has been assembled to form a neutron multiplicity detector for use in a superheavy element search. This array had a detection efficiency for fission neutrons of 37+or-2% and a neutron diffusion time of 83 mu s. The measured background rate of the array, when operated underground at a depth of 60 mwe, was 0.36+or-0.02 s-1.
Relation between the shape of population distribution and the robustness of four simple test statistics

SUMMARY The underlying theory upon which a great number of statistical procedures are based assumes that the variable or variables sampled are normally distributed. While there has been a good deal of theoretical research on the robustness of these procedures, the results seem not to have been set out in terms which the unsophisticated user of statistical methods can easily assimilate. The present paper, based on extensive computer simulation, aims at relating diagrammatically the shape of population to the robustness of the distribution of
A case study of the development of nocturnal slope flows in a wide open valley and associated air quality implications

This paper documents the development of nocturnal flows in the wide open Phoenix, Arizona (U.S.A) valley (30 km x 100 km) that is bordered by a large nearly flat plain to the west and high mountains to the north and east. Local thermally driven winds concomitant with the absence of significant synoptic pressure gradients dominate typical winter conditions in the Phoenix valley. The purpose of the Phoenix Air Flow Experiment (PAFEX-1) was to study the development of thermally driven flows during the evening transition in a sloping valley and describe the general pattern of transport and dispersion of contaminants during transition periods and at night. Measurements were made using a tethered balloon, sonic anemometer, balloon-based aerosol sampler, radiation sensors, cup anemometers, thermistors and humidity sensors in conjunction with data collected from 44 standard meteorological stations located throughout the valley. Over the period of 15 days in January and February 1998 the general diurnal flow patterns were repeatable, but varied substantially around the valley. This paper focuses on a case study of the evening transition, nocturnal circulation and morning breakdown of the nocturnal circulation on the night of 31 January and morning of 1 February. Central valley measurements were consistent with the notion that the evening transition is associated with a moving front, followed by intense mixing and the movement of the front to establish down-valley winds. Flows originating from different slopes led to the arrival of fronts at the various measurement locations at different times. These flows intrude into the valley and interact with each other, often causing multi-layered vertical structure. The intrusions respond to the evolving stratification and cause striking variability of these layers, for example, periodic wind and temperature disturbances corresponding to the arrival of new intrusive fronts. The evolution of the boundary layer was found to have a direct bearing on the pollution concentrations in the Phoenix air shed.
The International Journal of Biostatistics Inference in Epidemic Models without Likelihoods

Likelihood-based inference for epidemic models can be challenging, in part due to difficulties in evaluating the likelihood. The problem is particularly acute in models of large-scale outbreaks, and unobserved or partially observed data further complicates this process. Here we investigate the performance of Markov Chain Monte Carlo and Sequential Monte Carlo algorithms for parameter inference, where the routines are based on approximate likelihoods generated from model simulations. We compare our results to a gold-standard data-augmented MCMC for both complete and incomplete data. We illustrate our techniques using simulated epidemics as well as data from a recent outbreak of Ebola Haemorrhagic Fever in the Democratic Republic of Congo and discuss situations in which we think simulation-based inference may be preferable to likelihood-based inference.
A central limit theorem for empirical processes

Abstract The empirical measure Pn for independent sampling on a distribution P is formed by placing mass n−1 at each of the first n sample points. In this paper, n½(Pn − P) is regarded as a stochastic process indexed by a family of square integrable functions. A functional central limit theorem is proved for this process. The statement of this theorem involves a new form of combinatorial entropy, definable for classes of square integrable functions.
Radiative Damping in the Upper Mesosphere

Abstract Radiative damping rates of atmospheric temperature perturbations can be calculated by either an eigenvalue method or a scale-dependent Newtonian cooling method, which we show are equivalent in two limits. One limit is an infinite, homogeneous atmosphere based on Spiegel's model. The other, corresponding to an empirical scale-independent Newtonian cooling coefficient, is the transparent limit to radiation. In the upper mesosphere the damping rate is calculated by both methods using a non-LTE Curtis matrix. If the atmospheric application requires only thermal damping in a narrow altitude region for waves of small vertical wavelength or damping in a thick layer for large vertical wavelength waves, then one of these limits is a valid approximation. Under these circumstances the easily calculated, scale-dependent, Newtonian cooling rate gives a good approximation to the radiative damping rate. Scale-dependent radiative damping rates calculated with non-LTE Curtis matrices and an exact line-by-line int.
Cell lineage analysis: Variance Components Models for Dependent Cell Populations

Abstract Cells grown in culture can be tracked for several generations and measurements taken on size or age at division and other cell characteristics. The observations for the offspring of each cell form a family tree of dependent data. Such cell lineage data are here modeled as repeated measurements on different family trees arising from individual ancestor cells selected at random from a population of cultured cells. The bifurcating autoregression model is embedded in a process that allows for measurement error and variation from tree to tree. Robust methods are presented that accommodate outliers in this time-dependent and branching environment while allowing the statistician to interactively build a variance components model for the process. The methodology is illustrated on a substantial data set of 41 trees of EMT6 cells, with the surprising conclusion that after removing measurement error, sister-cell lifetimes are nearly identical.
On the Uniform Strong Consistency of Local Polynomial Regression Under Dependence Conditions

Abstract In this article, nonparametric estimators of the regression function, and its derivatives, obtained by means of weighted local polynomial fitting are studied. Consider the fixed regression model where the error random variables are coming from a stationary stochastic process satisfying a mixing condition. Uniform strong consistency, along with rates, are established for these estimators. Furthermore, when the errors follow an AR(1) correlation structure, strong consistency properties are also derived for a modified version of the local polynomial estimators proposed by Vilar-Fernández and Francisco-Fernández (Vilar-Fernández, J. M., Francisco-Fernández, M. (2002). Local polynomial regression smoothers with AR-error structure. TEST 11(2):439–464).
Bound-state interferometry using incoherent light

Rydberg states in sodium are excited using two identical broadband, dye laser pulses. Each 8 ns pulse has a bandwidth of approximately 45 cm-1, and Rydberg states with several different principal quantum numbers are simultaneously excited. The number of Rydberg atoms created by each pulse pair is detected as a function of the delay between the two pulses. Strong modulations in the population in each Rydberg level and in the total Rydberg signal are observed. The oscillations are identical to those which would be expected if two transform-limited, 300 fs laser pulses had been used. We show explicitly, in the limit of weak pulses, that these 'bound-state interferograms' acquired using the time-domain, Ramsey separated-oscillatory fields method are only dependent on the excitation cross section and pulse frequency spectrum. Therefore, weak-field interferograms do not in themselves give information on the spatial-distribution of the electron wavefunction. In addition, the benefits of using strong or weak pulses for bound-state interferometry are discussed.
Beugungserscheinungen an Doppelrastern

Stellt man 2 gleichartige Raster hintereinander, so wird in bestimmten Abstanden ein Raster durch das andere Raster abgebildet. Diese Abstande ergeben sich aus der Beugungstheorie. Sie werden berechnet und mit dem Experiment verglichen. Es ergibt sich dabei eine ganze Schar von Abstanden, die sich nach einem einfachen Gesetz aneinanderreihen. Bei der Berechnung der Gangunterschiede an den einzelnen Spalten bei den verschiedenen Abstanden ergaben sich auffallende, symmetrisch angelegte Folgen von Zahlen, die in einer Tabelle wiedergegeben sind.
Polymer-laden homogeneous shear-driven turbulent flow: a model for polymer drag reduction

Drag reduction (DR) under a turbulent boundary layer implies the suppression of turbulent momentum flux to the wall, a large-eddy phenomenon. Our hypothesis is that the essential mechanisms by which dilute concentrations of long-chain polymer molecules reduce momentum flux involve only the interactions among turbulent velocity fluctuations, polymer molecules and mean shear. Experiments indicate that these interactions dominate in a polymer-active ‘elastic layer’ outside the viscous sublayer and below a Newtonian inertial layer in a polymer-laden turbulent boundary layer. We investigate our hypothesis by modelling the suppression of momentum flux with direct numerical simulation (DNS) of homogeneous turbulent shear flow (HTSF) and the finite extensible nonlinear elastic with Peterlin approximation (FENE-P) model for polymer stress. The polymer conformation tensor equation was solved using a new hyperbolic algorithm with no artificial diffusion. We report here on the equilibrium state with fixed mean shear rate S, where progressive increases in non-dimensional polymer relaxation time WeS (shear Weissenberg number) or concentration parameter 1 − β produced progressive reductions in Reynolds shear stress, turbulence kinetic energy and turbulence dissipation rate, concurrent with increasing polymer stress and elastic potential energy. The changes in statistical variables underlying polymer DR with 1 − β, WeS, %DR and polymer-induced changes to spectra are similar to experiments in channel and pipe flows and show that the experimentally measured increase in normalized streamwise velocity variance is an indirect consequence of DR that is true only at lower DR. Comparison of polymer stretch and elastic potential energy budgets with channel flow DNS showed qualitative correspondence when distance from the wall was correlated to WeS. As WeS increased, the homogeneous shear flow displayed low-DR, high-DR and maximum-DR (MDR) regimes, similar to experiments, with each regime displaying distinctly different polymer–turbulence physics. The suppression of turbulent momentum flux arises from the suppression of vertical velocity fluctuations primarily by polymer-induced suppression of slow pressure–strain rate correlations. In the high-Weissenberg-number MDR-like limit, the polymer nearly completely blocks Newtonian inter-component energy transfer to vertical velocity fluctuations and turbulence is maintained by the polymer contribution to pressure–strain rate. Our analysis from HTSF with the FENE-P representation of polymer stress and its comparisons with experimental and DNS studies of wall-bounded polymer–turbulence supports our central hypothesis that the essential mechanisms underlying polymer DR lie directly in the suppression of momentum flux by polymer–turbulence interactions in the presence of mean shear and indirectly in the presence of the wall as the shear-generating mechanism.
Computational Fluid Dynamics Investigation of Counterflow Ejection Effects on a Body moving with High Speed

A major problem associated with the process of slowing down a body moving with high speed, such as during reentry of a space craft, is the extreme heat generated. Sink and ablation cooling are commonly used but the cost of such heat protection systems is very high. Thus heat dissipation has been an area of extensive research. The simulation work presented in this paper is attempted to replenish flow/ thermal field reaction with a greater details of the flow field affected by the deployment of counterflow jet ejection in supersonic freestream and test the suitability of different turbulence models. An Apollo command re-entry module has been employed and it has been subjected to a free stream Mach number of 3.0. ANSYS, as the computational fluid dynamics tool has been performed in this two-dimensional numerical flow simulation. Effects of counterflow jet injection effects and its interaction with the oncoming flow through the frontal stagnation point of the test module are discussed. Results obtained from different turbulence models are compared and analyzed. The overall outcomes are highly promising. Within those turbulence models, shear stress transport model (SST) seems to be preferred for such simulation. It also appears that substantial heat reduction on the body is possible using appropriate strength counter flow jet. Keywords-counterflow jet ejection, heat, turbulence model
Formal power series representation for gauge boson stars

We represent spherically symmetric, static, and non-singular solutions of the Einstein SU(2)-Yang-Mills and the Yang-Mills-dilaton system by means of formal power series expansions. Their coefficients are algebraically expressed in terms of new recursion relations. The solutions of Bartnik and McKinnon, found by numerical integration, are contained in our solution manifold.
Genetic algorithms for automatic algorithm and parameter selection in ATR applications

One of the difficulties that has been apparent in applying image processing algorithms not just for automatic target recognition but also for associated tasks in image processing and understanding is that of the optimal choice of parameters and algorithms. Firstly we must select an algorithm to use and secondly the actual parameters that are required by that algorithm. It is also the case that using a chosen algorithm on a different image class yields results of a totally different quality, here we consider three image classes, namely infra-red linescan, dd5-Russian satellite and SPOT imagery. We are now exploring the use of genetic algorithms for the purpose of parameter and algorithm selection and will show how the approach can successfully obtain results which in the past have tended to be obtained somewhat heuristically.
Lifting Surfaces With Circular Planforms

Wings with circular planforms are not common in aeronautics, although there are disc-like projectiles with sporting and recreational applications. There are some semi-analytic approaches in the literature (including by Miloh) to solution for the ∞ow over thin circular lifting surfaces, which yield exact or nearly exact results for ∞at discs at small angle of attack. These solutions are reviewed and compared with direct numerical solutions of the lifting surface integral equation. Solutions for non-∞at discs with small twist or camber are also discussed, including choice of twist or camber to minimise induced drag, or to achieve a favourable placement of the centre of pressure. Axisymmetrically cambered discs at zero angle of attack are paid special attention.
Supplemental Material for Bayesian Modelling of Difierential Gene Expression

1. WinBUGS Code This is the WinBUGS (Spiegelhalter et al., 1999) code for the model for biological replicates, given by equations (1), (2) and (3) but restricted to one condition s, with the posterior predictive checks on the gene variances. The constraint βgs. = 0 is imposed in WinBUGS using dummy “data” consisting of zeros (see main paper for details). The number of genes is n, where i = 1, . , n labels the gene, j = 1, . , 3 the array and k = 1, . , nk the polynomial in the array effect. The code shown here is for the model with piece-wise quadratic array effects; it can easily be modified to include a different functional form. We used version 1.4 of WinBUGS to run this model.
The influence of entropy fluctuations on the interaction of turbulence with a shock wave

Direct numerical simulation and inviscid linear analysis are used to study the interaction of a normal shock wave with an isotropic turbulent field of vorticity and entropy fluctuations. The role of the upstream entropy fluctuations is emphasized. The upstream correlation between the vorticity and entropy fluctuations is shown to strongly influence the evolution of the turbulence across the shock. Negative upstream correlation between u′ and T′ is seen to enhance the amplification of the turbulence kinetic energy, vorticity and thermodynamic fluctuations across the shock wave. Positive upstream correlation has a suppressing effect. An explanation based on the relative effects of bulk compression and baroclinic torque is proposed, and a scaling law is derived for the evolution of vorticity fluctuations across the shock. The validity of Morkovin's hypothesis across a shock wave is examined. Linear analysis is used to suggest that shock-front oscillation would invalidate the relation between urms and Trms, as expressed by the hypothesis.
Diode Laser Sensor for Gasdynamic Measurements in a Model Scramjet Combustor

A sensor for simultaneous and continuous measurements of water vapor density, temperature, and velocity has been developed based on absorption techniques using room temperature diode lasers (InGaAsP) operating at 1.31 µm. Laboratory calibrations of density and temperature were acquired in a variable temperature absorption cell and on a H 2‐air e at e ame burner from 500 to 2200 K. Laboratory determinations showed absolute accuracies of 5% in temperature and 10% in molecular density for a 0.3-Hz bandwidth. An optical system was developed for integratingthesensortoamodelscramjetcombustorattheU.S. AirForceResearchLaboratory,Wright ‐Patterson Air Force Base. Preliminary measurements in the Mach 2.1 e owe eld at expanded temperatures of 540, 650, and 740 K across an 18-cm pathlength resulted in temperature measurements that agreed with theoretical predictions to within 7‐11%. Density measurements agreed with predictions to within 17 ‐56%. Velocity measurement precision was compromised by beam steering effects, although results in reasonable agreement with predictions were observed at the lowest enthalpy condition.
CORRELATION EFFECTS IN ATOMIC STRUCTURE USING THE RANDOM-PHASE APPROXIMATION,

Abstract : A procedure for treating correlations in atomic structure is introduced and applied to the calculation of excitation energies, oscillator strengths, and photo-ionization cross sections. The method is the extension of the Hartree-Fock theory known as the random-phase approximation, which has already been applied to a number of other many-body problems. In this application to atomic physics, results are given for the following atoms in column II of the periodic table: beryllium, magnesium, calcium, and strontium. These atoms all have 1 sub S ground states, and only excitations to 1 sub P states are considered. The general conclusion of the study is that the values of the oscillator strengths and photo-ionization cross sections are changed significantly by the correlations, while the changes in the values of the excitation energies are quite small. Wherever comparison with experiment is possible, the inclusion of these correlations improves the agreement between theory and experiment. Their effects are, however, not as marked as in highly degenerate infinite systems or in nuclei. (Author)