Miracle-dz/UniFAR-FTUs huggingface dataset:
Eliassen–Palm Fluxes of the 2-Day Wave

Abstract High-Resolution Doppler Imager (HRDI) winds and temperatures are used to diagnose a 2-day wave event detected in the Southern Hemisphere during January 1994. A novel aspect of this study is the focus upon the wave fluxes throughout the 65–100-km range, and their relationship to the background state. A wave “packet” composed of zonal wavenumbers 2, 3, and 4 propagates westward with a phase speed near 60 m s−1. The periods associated with zonal wavenumbers 2, 3, and 4 are 3.5, 2.1, and 1.7 days, respectively. The morphology of the 2-day temperature and wind fields is consistent with that of a developing baroclinic wave. The divergence of the Eliassen–Palm flux of zonal wavenumbers 2–4 is dominated by the vertical convergence of meridional heat flux. The wave driving (or Eliassen–Palm flux divergence per unit mass) is predominantly westward, with magnitudes on the order of 5 m s−1 day−1. A steady-state quasigeostrophic model of the mean meridionaI circulation is used to estimate the mean wind respon.
Explicit solutions of the Rand Equation

In this paper the meaning of a nonlinear partial differential equation (nPDE) of the third-order is shown to the first time. The equation is known as the ‘Rand Equation’ and belongs to a class of less studied nPDEs. Both the explicit physical meaning as well as the behaviour is not known until now. Therefore we believe it is indispensable to study this evolution equation in detail. We perform a classical Lie Group analysis to analyze the point symmetries. By using a similarity reduction we are able to deduce more classes of solutions of general character. Special nonlinear transformations are given in a most general form. In addition, we also study Lie’s non-classical case relating to potential and generalized symmetries. Both the potential and approximate symmetries are discussed to the first time leading to new results. So we expect a better understanding and concrete physical as well as technical application in future. Keywords: Nonlinear partial differential equations, evolution equations, symmetries, similarity solutions, Rand Equation.
An Analysis of the Dismal Theorem

In a series of papers, Martin Weitzman has proposed a Dismal Theorem. The general idea is that, under limited conditions concerning the structure of uncertainty and preferences, society has an indefinitely large expected loss from high-consequence, low-probability events. Under such conditions, standard economic analysis cannot be applied. The present study is intended to put the Dismal Theorem in context and examine the range of its applicability, with an application to catastrophic climate change. I conclude that Weitzman makes an important point about selection of distributions in the analysis of decision-making under uncertainty. However, the conditions necessary for the Dismal Theorem to hold are limited and do not apply to a wide range of potential uncertain scenarios.
Boundary-layer receptivity for a parabolic leading edge

The effect of the nose radius of a body on boundary-layer receptivity is analysed for the case of a symmetric mean flow past a body with a parabolic leading edge. Asymptotic methods based on large Reynolds number are used, supplemented by numerical results. The Mach number is assumed small, and acoustic free-stream disturbances are considered. The case of free-stream acoustic waves, propagating obliquely to the symmetric mean flow is considered. The body nose radius, rn, enters the theory through a Strouhal number, S = ωrn/U, where ω is the frequency of the acoustic wave and U is the mean flow speed. The finite nose radius dramatically reduces the receptivity level compared to that for a flat plate, the amplitude of the instability waves in the boundary layer being decreased by an order of magnitude when S = 0.3. Oblique acoustic waves produce much higher receptivity levels than acoustic waves propagating parallel to the body chord.
The thermodynamics of saturated air: A contribution to the classical theory

The temperature attained in the reversible and pseudo-adiabatic expansion of air saturated with respect to liquid water is taken as a reference; the temperatures attained in the following expansions from the same initial state are then compared with it: (a) the ice-saturation pseudo-adiabatic process (b) the water-saturation adiabatic process (c) the ice-saturation adiabatic process. The results of these comparisons are summarized in Figs. 1 to 5 of this paper. Similarly, the cloud virtual temperature, the virtual temperature adjusted for the weight of suspended particles, attained in water-saturation adiabatic expansion, is compared with that attained in water-saturation pseudo-adiabatic expansion; Fig. 6. The implications of these calculations for the properties and behaviour of cumulus are commented upon.
Fuzzy hyperbolic H∞ filter design for a class of nonlinear continuous-time dynamic systems

This paper studies fuzzy hyperbolic H∞ filter for signal estimation of nonlinear continuous-time systems with unknown bounded disturbances. The fuzzy hyperbolic model (FHM) is a universal approximator, and can be used to establish models for unknown complex systems. Furthermore, the main advantage of using the FHM over the Takagi-Sugeno fuzzy model are that no premise structure identification is needed and no completeness design of premise variables space is needed. Also an FHM is a kind of valid global description and nonlinear model in nature. First, FHM is proposed to represent the state-space model for nonlinear continuous -time systems. Next, we design a stable fuzzy H∞ filter based on the FHM, which assures asymptotic stability and a prescribed H∞ index for the filtering error system. A sufficient condition for the existence of such a filter is established through seeking the feasible solutions of a linear matrix inequality (LMI). Under the position and the dimension criteria, a new LMI condition is obtained to reduce the conservativeness for the analysis and design of fuzzy H∞ filter based on extended e-block and λ -block and the corresponding equivalent forms. Simulation examples are provided to illustrate the design procedure of the proposed method.
A Novel Approach for Fingerprint Sparse Coding Analysis using K-SVD Learning Technique

:- Fingerprint is one of the most important security systems in Biometrics. Biometrics refers to the authentication techniques. In biometrics it can be classified into several types, they are face, fingerprint, retina, hand geometry etc. In this paper they introduced a new fingerprint compression algorithm. This algorithm is based on sparse representation. On the basis of a set of fingerprint patches got from over complete dictionary we are allowed to represent a sparse linear combination of dictionary atoms. A dictionary for predefined fingerprint image patches is constructed first in the algorithm. Because the patches are represented by a new given fingerprint images as per the computing l 0 – minimization and quantize and encode the representation of the dictionary. The effect of various factors on compression results is considered by us here and for that we test three groups of fingerprint images. It is demonstrated that several competing compression techniques (JPEG, JPEG 2000, and WSQ) especially at high compression ratios are not as efficient as our algorithm. It is also illustrated that the proposed algorithm is robust to extract minutiae.
A transfer-matrix approach to random resistor networks

Introduces a transfer-matrix formulation to compute the conductance of random resistor networks. The authors apply this method to strips of width up to 40, and use finite size scaling arguments to obtain an estimate for the conductivity critical exponent in two dimensions, t=1.28+or-0.03.
Decomposition of one-dimensional waveform using iterative Gaussian diffusive filtering methods

The Gaussian smoothing method is shown to have a wide transition zone around the cut-off frequency selected to filter a given dataset. We proposed two iterative Gaussian smoothing methods to tighten the transition zone: one being approximately diffusive and the other being strictly diffusive. The first version smoothes repeatedly the remaining high-frequency parts and the second version requires an additional step to further smooth the resulting smoothed response in each of the smoothing operation. Based on the choice of the criterion for accuracy, the smoothing factor and the number of iterations are derived for an infinite data length in both methods. By contrast, for a finite-length data string, results of the interior points (sufficiently away from the two endpoints) obtained by both methods can be shown to exhibit an approximate diffusive property. The upper bound of the distance affected by the error propagation inward due to the lack of data beyond the two ends is numerically estimated. Numerical experiments also show that results of employing the iterative Gaussian smoothing method are almost the same as those obtained by the strict diffusive version, except that the error propagation distance induced by the latter is slightly deeper than that of the former. The proposed method has been successfully applied to decompose the wave formation of a number of test cases including two sets of real experimental data.
Experimental and theoretical study of the inhomogeneous electron kinetics in the dc column plasma

The radial change of the electron velocity distribution function and of related macroscopic quantities of the electrons are studied theoretically and experimentally in the positive column plasma of a neon dc low pressure glow discharge. The theoretical investigations are based on the solution of electron kinetic equations. The measurements of electron kinetic quantities are performed by using a single probe technique with automated recording. To avoid the strict treatment of the complicated radially varying electron kinetics in the microphysical description of the column plasma, various simplifications of the appropriate inhomogeneous kinetic equation have been adopted in the past. Recently a strict solution approach of this complex kinetic problem could be developed. Using this strict solution approach and experimentally determined electron kinetic quantities the approximation quality, obtained by applying various simplified approaches to treat the electron kinetics as the conventional homogeneous approach, the nonlocal approach and the local field approximation, is illustrated and critically evaluated in this paper.
Trilateration-Based Localization Algorithm Using the Lemoine Point Formulation

ABSTRACT The centroid of three most closely spaced intersections of constant-range loci is conventionally used as trilateration estimate without rigorous justification. In this paper, we address the quality of trilateration intersections through range scaling factors. Several triangle centres, including centroid, incentre, Lemoine point, and Fermat point, are discussed in detail. Lemoine point (LP) is proposed as the best trilateration estimator thanks to the desired property that the total distance to three triangle edges is minimized. It is demonstrated through simulation that LP outperforms centroid localization without additional computational load. In addition, severe trilateration scenarios such as two-intersection cases are considered in this paper, and enhanced trilateration algorithms are proposed.
African Climate Change: Taking the Shorter Route

Numerous factors are associated with poverty and underdevelopment in Africa, including climate variability. Rainfall, and climate more generally, are implicated directly in the United Nations "Millennium Development Goals" to eradicate extreme poverty and hunger, and reduce child mortality and incidence of diseases such as malaria by the target date of 2015. But, Africa is not currently on target to meet these goals. We pose a number of questions from a climate science perspective aimed at understanding this background: Is there a common origin to factors that currently constrain climate science? Why is it that in a continent where human activity is so closely linked to interannual rainfall variability has climate science received little of the benefit that saw commercialization driving meteorology in the developed world? What might be suggested as an effective way for the continent to approach future climate variability and change? We make the case that a route to addressing the challenges of climate change in Africa rests with the improved management of climate variability. We start by discussing the constraints on climate science and how they might be overcome. We explain why the optimal management of activities directly influenced by interannual climate variability (which include the development of scientific capacity) has the potential to serve as a forerunner to engagement in the wider issue of climate change. We show this both from the perspective of the climate system and the institutions that engage with climate issues. We end with a thought experiment that tests the benefits of linking climate variability and climate change in the setting of smallholder farmers in Limpopo Province, South Africa
Type II-L supernovae-standard bombs

A method for deriving supernovae (SNs) luminosity functions is presented and it is used to derive the luminosity distribution of Type II SNs with «linear» light curves (SN II-L's). The luminosity function (of the absolute B-magnitude at maximum) can be represented by a Gaussian centered on M B = -16.45 with a 1 σ dispersion of only ± 0.3 mag and a few higher luminosity SNs. The scatter about the mean is consistent with the uncertainties in the apparent B-magnitude at maximum and in the distances to the host galaxies
Sensitivity of the Residual Circulation Diagnosed from the UARS Data to the Uncertainties in the Input Fields and to the Inclusion of Aerosols

Abstract The simultaneous measurements of temperature, aerosol extinction, and concentrations of radiatively active gases by several instruments aboard the Upper Atmosphere Research Satellite permit an assessment of the uncertainties in the diagnosed stratospheric heating rates and in the resulting residual circulation. In this paper, measurements taken by the Cryogenic Limb Array Etalon Spectrometer (CLAES) are used to compute the circulation and to compare it against values obtained previously from the measurements obtained by the Microwave Limb Sounder (MLS). There is a broad agreement between the two sets of calculations and known biases in either CLAES or MLS ozone and temperature measurements are found to be responsible for the areas of disagreement. The inclusion of aerosols has improved the estimates of the residual circulation in the lower stratosphere during the 1992–93 period covered by CLAES. Present estimates of the aerosol heating are significantly different from those found in other studies.
An analytic approach to tensor scale with efficient computational solution and applications to medical imaging

Scale is a widely used notion in medical image analysis that evolved in the form of scale-space theory where the key idea is to represent and analyze an image at various resolutions. Recently, a notion of local morphometric scale referred to as “tensor scale” was introduced using an ellipsoidal model that yields a unified representation of structure size, orientation and anisotropy. In the previous work, tensor scale was described using a 2-D algorithmic approach and a precise analytic definition was missing. Also, with previous framework, 3-D application is not practical due to computational complexity. The overall aim of the Ph.D. research is to establish an analytic definition of tensor scale in n-dimensional (n-D) images, to develop an efficient computational solution for 2and 3-D images and to investigate its role in various medical imaging applications including image interpolation, filtering, and segmentation. Firstly, an analytic definition of tensor scale for n-D images consisting of objects formed by pseudo-Riemannian partitioning manifolds has been formulated. Tensor scale captures contextual structural information which is useful in local structure-adaptive anisotropic parameter control and local structure description for object/image matching. Therefore, it is helpful in a wide range of medical imaging algorithms and applications. Secondly, an efficient computational solution of tensor scale for 2and 3-D images has been developed. The algorithm has combined Euclidean distance transform and several novel differential geometric approaches. The accuracy of the algorithm has been verified on both geometric phantoms and real images compared to the theoretical results generated using brute-force method. Also, a matrix representation has been derived facilitating several operations including tensor field smoothing to capture larger contextual knowledge. Thirdly, an inter-slice interpolation algorithm using 2-D tensor scale information of adjacent slices has been developed to determine the interpolation line at each image
Improvement of the element-free Galerkin method for electromagnetic field calculation

The element-free Galerkin method (EFGM) is meshless method, it can solve some problems that the finite element method (FEM) can not solve effectively in electromagnetic field, such as thin plate problems, narrow gap problems, moving conductors, etc. In this paper, an improved formulation of the EFGM is proposed for electromagnetic field computations. Detailed research is conducted on some key problems, such as the selection of the weight function, the treatment of imposing boundary conditions and interface conditions. Finally, numerical examples are cited for demonstration.
The influence of crack shape on the effective elasticity of fractured rocks

A circle is the basic fracture shape adopted by conventional effective media theories to describe the overall elasticity of cracked solids. Fractures in rocks do not resemble circles, so it is important to find out to what extent the available theoretical results apply to realistic fracture shapes. To address this issue, we conduct 3D numerical experiments on the so-called digital rocks containing irregular cracks that might be partially closed and might intersect each other. Despite profound deviations of our fracture geometries from circles, we find that basic theoretical results originally developed for penny-shaped cracks remain valid for arbitrary fracture shapes. Based on a series of finite-element computations, we show that as far as the effective elasticity is concerned, flat fractures with random in-plane irregularities are represented accurately by circular ones. We also show that approximate effective elliptical orthotropy established for multiple sets of dry, penny-shaped cracks embedded in is.
Matrix‐analytic Models and their Analysis

We survey phase‐type distributions and Markovian point processes, aspects of how to use such models in applied probability calculations and how to fit them to observed data. A phase‐type distribution is defined as the time to absorption in a finite continuous time Markov process with one absorbing state. This class of distributions is dense and contains many standard examples like all combinations of exponential in series/parallel. A Markovian point process is governed by a finite continuous time Markov process (typically ergodic), such that points are generated at a Poisson intensity depending on the underlying state and at transitions; a main special case is a Markov‐modulated Poisson process. In both cases, the analytic formulas typically contain matrix‐exponentials, and the matrix formalism carried over when the models are used in applied probability calculations as in problems in renewal theory, random walks and queueing. The statistical analysis is typically based upon the EM algorithm, viewing the whole sample path of the background Markov process as the latent variable.
A generalized solution to the adaptive nulling problem in the presence of coherent jammers

The solution suggested by A.K. Luthra (1986) for the adaptive nulling problem with a look-direction constraint in the presence of coherent jammers, but under the realistic assumption of independent numbers of array elements and of coherent jammers, is reinvestigated. Some limitations of this solution are pointed out. A generalized solution is proposed which has additional useful merits of being less complex and of increased adaptation speed. Computer simulations validated the correctness of the presented theoretical arguments. >
Theoretical analysis of a modified Koch monopole with reduced dimensions

Fractal antennas are characterised by their special geometric characteristics, which allow a reduction of the antenna dimensions. The fractal parameters and the radiative properties of modified Koch monopoles are analysed. The geometries of the antennas are obtained by an ad hoc iterative function system algorithm for fractal curve generation. Using the method of moments for numerical calculations, the influence of the antenna geometry on the resonant frequency, current, efficiency, input impedance and radiation pattern are analysed.
Laser-induced oscillatory instabilities in amorphous materials

An oscillatory behaviour of the optical properties of amorphous materials is observed as a function of time, when the samples are irradiated by CW laser beams. The Raman TO peak and line width have a quasi-periodic behaviour parallel to that of the transmitted light, which indicate a structural oscillation between metastable states. A kinetic model is proposed, which is based on the generation of hot mobile electrons by the laser and on thermally activated atomic transitions between metastable states assisted by the transient local energy release caused by the electron trapping.
Depletion-mode InGaAs metal-oxide-semiconductor field-effect transistor with oxide gate dielectric grown by atomic-layer deposition

Recently, significant progress has been made on GaAs metal-oxide-semiconductor field-effect transistors (MOSFETs) using atomic-layer deposition (ALD)-grown Al2O3 as gate dielectric. We show here that further improvement can be achieved by inserting a thin In0.2Ga0. 8As layer as part of the channel between Al2O3 and GaAs channel. A 1-μm-gate-length, depletion-mode, n-channel In0.2Ga0. 8As/GaAs MOSFET with an Al2O3 gate oxide of 160 A shows a gate leakage current density less than 10−4 A/cm2, a maximum transconductance ∼105 mS/mm, and a strong accumulation current at Vgs>0 in addition to buried-channel conduction. Together with longer gate-length devices, we deduce electron accumulation surface mobility for In0.2Ga0. 8As as high as 660 cm2/V s at Al2O3/In0.2Ga0. 8As interface.
Sonodynamic approach to tumor treatment

The localization of sonochemical reactions with focused ultrasound is investigated by developing a sonochemically active tissue mimicking phantom. It is demonstrated that the sonochemical effects can be localized within a region of size not larger than typical tumors to be treated. Sonochemically efficient methods of ultrasound irradiation, which may neither require standing wave situations nor extremely high ultrasound intensity in order to induce substantial sonochemical effects, are studied. The ultrasound intensity threshold for the sonochemical reaction is drastically decreased by the second harmonic superimposition. It is also demonstrated by in vitro experiments that a gallium-deuteroporphyrin complex, ATX-70, has three times higher sonochemical activity than hematoporphyrin (Hp) and induces cell damage at twice the rate of Hp in combination with ultrasound. <<ETX>>
Simulating cyclic voltammetry under advection for electrochemical cantilevers

We present a mathematical model describing an electrochemical system involving electrode–electrolyte interaction. The model is governed by a system of advection–diffusion equations with a nonlinear reaction term at the boundary. Our calculations based on such model demonstrate the dynamics of ionic currents in the electrolyte. The model allows us to predict the effect of varying flow rates, scan rates, and electrolyte concentration of the electrochemical system. Copyright © 2014 John Wiley & Sons, Ltd.