Miracle-dz/UniFAR-FTUs huggingface dataset:
Using Frequency Distributions of Catch per Unit Effort to Measure Fish‐Stock Abundance

Abstract Mean catch per unit effort often is used as an index of fish abundance, N. This index is often biased. Frequency distributions of catch per unit effort (C/f) and independent estimates of N from a headboat sport fishery for yellowtail snappers Ocyurus chrysurus off Islamorada, Florida, indicated that mean C/f underestimated changes in N. Frequency distributions of C/f were skewed and fit the negative binomial distribution. Some descriptors of the distributions (median, variance, negative binomial parameter k, and frequency of zero C/f) were systematically related to N. These relationships were used to derive an index of N less biased than mean C/f. The new index, square root of relative frequency of zero C/f, could be applicable to any recreational, scientific, or commercial fishing activity for which C/f distributions are available, skewed, and have fairly high frequencies of zero C/f. Skewness could be due to spatial dispersion of the fish population or to a gradient of skill among fishing units.
Decoherence without dissipation due to fermionic bath

On the basis of the formalism of the fermionic coherent state of Cahil and Glauber (1999 Phys. Rev. A 59 1538), we have provided an exact solution to a model of a harmonic oscillator coupled to a fermionic environment via a quantum non-demolition type interaction. Quantum phase diffusion and linear entropy dynamics show their signature felt by the suppression of decoherence with temperature in comparison to the bosonic bath case, which may be worth investigating for their application in the coherent dynamics domain at finite temperature. We have shown an unconventional motional narrowing of the quantum Kubo oscillator, which is realized from this model due to the antibunching character of fermionic quantum noise. It is possible to bring this out explicitly here by the consideration of the non-commutative property of interaction obeying the Grassmann algebra.
Local Buckling in Crease Induced by Wrapping Fold of Space Membrane

This paper addresses the mechanics of local buckling induced in the creased membrane, which determines the folded size and the residual deformation of space membranes. The details of local buckling are investigated by demonstrating finite-element simulations. Based on properties of local buckling obtained through simulations, a simple analytical model is formulated in consideration of the deformed shape of the creased membrane to identify the dominant parameters and the conditions for local buckling. These results are verified by performing wrapping fold experiments. Based on these results, the mechanics of local buckling are discussed. The dominant parameters of local buckling are obtained by theoretical analysis in terms of the tensile force, the membrane thickness, the interval of the fold line, and the center hub radius. Conditions for local buckling are identified as the function of the dominant parameters, and the conditions show good agreement with the experimentally obtained results.
Recursive Estimation in Diffusion Model

This paper is concerned with the nonlinear identification of dynamical systems disturbed by white noise, an important problem in control engineering. A nonparametric identification procedure for such systems which are usually described by a diffusion model is given in Banon (1977), (1978), where weak consistency of estimators has been obtained and simulation study has been carried out successfully. In this paper, we prove a stronger result concerning asymptotic properties of the estimators of the drift term, namely, strong consistency, and also related results.
Introducing multi‐dimensional ‘hybrid wavelets’ for enhanced evaluation of hyperspectral image cubes and multi‐way data sets

Multi‐dimensional wavelet transforms (WTs) have been introduced for efficient data compression in order to accelerate chemometric calculations and to reduce requirements for data storage space. For hyphenated measurement techniques or hyperspectral imaging this wavelet compression becomes vital because such sensors acquire unprecedented amounts of information in short periods of time. Conventional, multi‐dimensional wavelet compression uses the same wavelet for all dimensions. However, from a mathematical perspective there is no need for this restriction as the transforms in different dimensions are independent from each other. This manuscript presents multidimensional ‘hybrid wavelet transforms’, which utilize different wavelet types for different dimensions. Thus, hybrid wavelets optimize wavelet compression by adjusting WTs to the different types of data sets. In this manuscript we demonstrate that hybrid wavelets improve acceleration factors compared to conventional multi‐dimensional wavelet compression and determine more precise models. Combinations of Haar, Daub4, Daub6, Daub8, Daub10, Daub12, Daub14, Daub16, Daub18 and Daub20 wavelets are considered in this study. Data obtained with two different experimental techniques are used for assessing hybrid wavelet compression: (i) a data cube obtained by means of mid‐infrared hyperspectral imaging; (ii) data acquired by excitation‐emission matrix (EEM) fluorescence spectroscopy in photo‐catalytic studies. For the hyperspectral data cube hybrid wavelets were found, which are superior regarding acceleration and model quality to all 10 conventional WTs (Haar–Daub20). For the EEM example this was achieved in 9 out of 10 cases; thus in 19 out of 20 investigated cases hybrid WTs were found to be superior to conventional wavelet compression. Copyright © 2006 John Wiley & Sons, Ltd.
Aggregation Decomposition and Aggregation Guidelines for a Class of Minimax and Covering Location Models

Facility location problems often involve movement between facilities to be located and customers/demand points, with distances between the two being important. For problems with many customers, demand point aggregation may be needed to obtain a computationally tractable model. Aggregation causes error, which should be kept small. We consider a class of minimax location models for which the aggregation may be viewed as a second-order location problem, and use error bounds as aggregation error measures. We provide easily computed approximate Òsquare rootÓ formulas to assist in the aggregation process. The formulas establish that the law of diminishing returns applies when doing aggregation. Our approach can also facilitate aggregation decomposition for location problems involving multiple ÒseparateÓ communities.
Numerical and Experimental Analyses of the Ducted Fan for the Small VTOL UAV Propulsion

Ducted fans have higher thrust performance, higher propulsion efficiency and lower noise characteristics due to their duct system compared with commercial isolated propellers. The purpose of this study is to present design procedures in order to improve the aerodynamic performance of the ducted fan for the small VTOL UAV propulsion. In addition, the duct effect of ducted fans is analyzed to satisfy design requirements and improve performance. Aerodynamic design of the rotor and the stator blades of the ducted fan involves a series of steps: meanline analysis, through-flow analysis and aerodynamic analysis, based on consideration of the design requirements. The thrust performance of the ducted fan is somewhat higher compared with that of the rotor only, but wind tunnel test results of the ducted fan do not satisfy the design requirements. The thrust performance of the ducted fan is significantly different in the CFD results and wind tunnel results due to the inconsistency of the intake and the duct shape. Therefore, the thrust performance of the ducted fan would be somewhat improved by the optimization of the intake and the duct shape.
D-optimal designs for mixed discrete and continuous outcomes analyzed using nonlinear models

Many dose-response experiments in toxicology and other biological sciences are designed to measure multiple outcomes. Unfortunately, most of these studies are powered or designed for a single response, and the inference on the under-powered endpoints is limited. As additional design challenges, the outcomes may have different regions and shapes of activity or have different response types. As a new application to the traditional D-optimality criterion, we have developed optimal designs for mixed discrete and continuous outcomes that are analyzed with nonlinear models. These designs use a numerical algorithm to choose the location of the dose groups and proportion of total sample size allocated to each group that minimize the generalized variance of a model-based covariance matrix that incorporates the correlation between outcomes. Using this methodology, we designed a dose-response experiment with binary, count, and continuous outcomes to evaluate neurotoxicity. In this example, the optimal designs placed dose groups at the predicted dose thresholds and throughout the active range. The designs were generally robust to different correlation structures. In addition, when the expected correlation was moderate or large, we observed a substantial gain in efficiency compared to optimal designs created for each outcome separately.
Dynamical mapping of hot stellar systems

We show how to recover the distribution function f(E, L 2 ) of an equilibrium population in a spherical stellar system, as well as the gravitational potential Φ(r) in which that population orbits, given its joint distribution of apparent positions and line-of-sight velocities. No assumptions are made about the variation with radius of the mass-to-light ratio or the form of f. Practical nonparametric algorithms are presented for the case of continuous data, as derived from integrated stellar spectra, and discrete data, in the form of individual radial velocities
Convergence of a multiple reflection method for calculation stokes flow in a suspension

The calculation of solutions of Stokes equations in the complex geometry of a suspension with many particles of arbitrary shape and arrangement is reduced to a sequence of calculations of flows with single particle boundary conditions. The sequence of approximate solutions converge to the solution of the full problem in the energy dissipation norm at an exponential rate. The convergence proof is based on the observation that the flow in a suspension minimizes the rate of energy dissipation over a certain class of flows. Each flow in the approximating sequence minimizes the rate of dissipation over a subclass of these flows containing the previous flow, so the energy dissipation norm is decreasing monotonically. From the latter minimum principle, it follows that each approximate flow is obtained from the previous one through application of one of a finite number of orthogonal projection operators. The properties of the subspaces of flows associated with these projections assure that the sequence converges.
Cascaded silicon Raman lasers as mid-infrared sources

It is shown by numerical simulations that cascaded silicon Raman lasers, in which the pump light undergoes multiple Stokes shifts in a silicon waveguide, can efficiently convert near-IR to mid-IR radiation. For pump wavelengths significantly below 2 µm, two-photon-absorption-induced free-carrier absorption degrades conversion efficiency, and the effective carrier lifetime determines the shortest possible pump wavelength.
A large Time Step Generalization of Godunov’s Method for Systems of Conservation Laws

A generalization of Godunov–s method for solving systems of conservation laws is proposed which can be applied for arbitrarily large time steps. Interactions of waves from neighboring Riemann problems are handled in an approximate but conservative manner that is exact for linear problems. For nonlinear systems it is found that better accuracy and sharper resolution of discontinuities is often obtained with Courant numbers somewhat larger than those allowed in Godunov's method. We explore the reasons for this behavior and, more generally, the effects of approximating wave interactions linearly. This linearization is easy to implement and may also be useful in other contexts, such as mesh refinement or shock tracking. A large time step generalization of the random choice method is also mentioned.
Shear Excitation of Gravity Waves. Part I: Modes of a Two-Scale Atmosphere

Abstract The stabilities of two model tropospheric jets are compared. The first jet is a simple, smooth, idealized profile governed by a single scale length of tropospheric dimensions. The second jet takes the first model flow and superimposes on it a localized deformation of much smaller scale. In this second model, the shears deriving from the small-scale structure provide the subcritical Richardson numbers that support instability. The two-scale model produces a much wider range of wave instabilities. Its Kelvin-Helmholtz waves span a wavenumber domain that is nearly two orders of magnitude wider than the domain of the one-scale model, while the gravity shear waves fill out into the small wavenumber areas of the stability diagrams. However, the growth rates of the instabilities displace significantly toward smaller scales in the two-scale model. It is suggested that the two-scale model is probably geophysically more realistic, and removes the necessity for deep layers of subcritical Richardson numbers,.
Surface Feature Extraction Based on Curvelet Transform from Point Cloud Data

Aiming at multi directions analysis problem of surface feature extraction from point cloud data, Curvelet transform is introduced to multi directions analysis of point cloud data. Based on the preprocessing of location and expansion, second-generation discrete Curvelet transform is used to analyze point cloud data. Curvelet transform coefficients are processed to enhance the contour of point cloud data. Nonlinear function is used to process Curvelet transform coefficients of coarse layer. Compromise for soft and hard thresholds is used to process Curvelet transform coefficients of detail layer. Piecewise nonlinear function is used to process Curvelet transform coefficients of fine layer. The data point is reconstructed from the enhanced Curvelet transform coefficient with Curvelet inverse transformation. Initial surface feature is achieved with edge detection. The precise surface feature is achieved with morphological dilation and erosion to filter edge without real shape significance. Example of part point cloud data of brake shell shows the proposed surface feature extraction method can accurately extract surface feature from data point.
Electron density diagnositc line ratios from the n = 3 lines of O v

New atomic physic calculations are presented for electron excitation rates for transitions between the n = 2 and n = 3 levels of O v. These are used to calculate theoretical line intensity ratios for the 192 A, 215 A, 220 A and 248 A lines of O v. These line intensity ratios are electron density sensitive and provide valuable diagnostics at T/sub e/approx.2 x 10/sup 5/ K for samll impulsive flare events in which the transition zone ions are enhanced relative to the coronal ions. Two flares observed by NRL spectroheliograph on Skylab, on 1973 December 22 and 1974 January 21, are studied, with electron densities of approximately 3 x 10/sup 11/ cm/sup -3/ being deduced.
LMI solutions to the mixed ℋ︁−/ℋ︁∞ fault detection observer design for linear parameter‐varying systems

This paper addresses the mixed ℋ︁−/ℋ︁∞ fault detection observer design issue for a class of linear parameter‐varying (LPV) systems. Analogous to the definition of the quadratic ℋ︁∞ performance for LPV systems and the ℋ︁− index for linear time invariant (LTI) systems, the quadratic ℋ︁− index and the affine quadratic ℋ︁− index for LPV systems are defined in terms of linear matrix inequalities (LMIs). The first algorithm for designing the mixed ℋ︁−/H∞ observer is proposed, which aims at minimizing the quadratic ℋ︁∞ performance and maximizing the quadratic ℋ︁− index of the observer error dynamic systems. To reduce the conservativeness of this algorithm, the affine quadratic ℋ︁∞ performance and the affine ℋ︁− index for LPV systems are utilized. The robustness conditions and affine ℋ︁− index conditions for the underlying observer optimization issue are formulated as parameter‐dependent LMIs. The Gridding technique and multi‐convexity concept are applied, respectively, for reducing the parameter‐dependent LMIs to finite LMI constraints. Correspondingly, two iterative algorithms are proposed. Furthermore, the threshold design and the estimation of the worst undetectable fault size are investigated. An example is studied to demonstrate the effectiveness of the proposed algorithms. Copyright © 2010 John Wiley & Sons, Ltd.
Scattering near specular direction for horizontally oriented ice discs

Scattering phase function on horizontally oriented ice particles near the specular reflective direction is analytically modeled using a mixed method combining direct reflection and Fraunhofer diffraction components, where particles are simply treated as circular facets and the effect of fluttering is introduced under the assumption of Gauss distribution. The obtained model expression reveals that the essence of far-field scattering around specular direction is the diffraction pattern modulated by fluttered geometric reflection. Four groups of experiments are designed to validate this model at different wavelengths and incidence angles, and the calculated phase functions present good agreement both in distributions and peak values with that of T-matrix method in conjunction with a Monte Carlo stochastic process.
Effects of Mach Number and Specific Heat Ratio on Low-Reynolds-Number Airfoil Flows

The effects of Reynolds number, Mach number, and gas species (air and CO2) on aerodynamic characteristics of a thin flat plate and a NACA 0012-34 airfoil were investigated under low-Reynolds-number (Re=0.43×104 to 4.1×104) and high-subsonic-flow (M=0.1 to 0.6) conditions. In addition to lift and drag measurements by a two-component balance system, the pressure-sensitive paint technique was applied to measure pressure profiles on the model surface. For the flat plate, the Reynolds number moderately affects the lift and drag characteristics because of a simple behavior of the leading-edge separation bubble; the length of the separation bubble increases as the angle of attack increases. By contrast, the Mach number and specific heat ratio contribute little to the aerodynamic performance. For the NACA 0012-34 airfoil, the lift curves are highly dependent on the Reynolds number because of the formation, shift, and burst of the separation bubble, whereas the compressibility affects only the stall characteristic.
Prediction of Space-Time Correlations by Large Eddy Simulation

﻿The recently increasing application of large eddy simulation to unsteady problems [1], suchnas turbulence-generated sound and turbulent reacting flows, requires that large-eddy simulation n (LES) with a sub-grid scale (SGS) model could accurately predict space-time correlations. Mostnof the currently existing SGS models are based on the energy budget equations. Therefore, theynare able to correctly predict energy spectra at large scales, but they may not accurately predictnother statistical quantities that are not determined fully by large-scale energy spectra, such asnspace-time correlations. In this paper, we will investigate the effects of SGS modeling on space-time correlations in LES. The numerical simulations of isotropic turbulence [2, 3] and turbulencenchannel flows [4] show that, compared with the results of direct numerical simulation (DNS), LES under-predicts the un-normalized correlation magnitude and over-predict the decorrelation time scales. This can lead to inaccurate solutions in applications such as sound power spectra. Innturbulence-generated sound, according to Lighthill's theory, the acoustic intensity radiated bynturbulent flows depends on two-point, two-time correlations, or Eulerian space-time correlations. Therefore, an accurate calculation of the Eulerian space-time correlation is important to the prediction of the sound radiations. The application of space-time correlations to acoustic powernin LES is also discussed. n
Unsteady flow calculation in a radial flow centrifugal pump with spiral casing

SUMMARY The prediction of the two-dimensional unsteady flow established in a radial flow centrifugal pump is considered. Assuming the fluid incompressible and inviscid, the velocity field is represented by means of source and vorticity surface distributions as well as a set of point vortices. Using this representation, a gridfree (Lagrangian) numerical method is derived based on the coupling of the boundary element and vortex particle methods. In this context the source and vorticity surface distributions are determined through the non-entry boundary condition together with the unsteady Kutta condition. In order to satisfy Kelvin's theorem, vorticity is shed at the trailing edges of the impeller blades. Then the vortex particle method is used to approximate the convection of the free vorticity distribution. Results are given for a pump configuration experimentally tested by Centre Technique des Industries Mecaniques (CETIM). Comparisons between predictions and experimental data show the capability of the proposed method to reproduce the main features of the flow considered.
A partial inexact alternating direction method for structured variational inequalities

In this article, a new method is proposed for solving a class of structured variational inequalities (SVIs). The proposed method is referred to as the partial inexact proximal alternating direction (piPAD) method. In the method, two subproblems are solved independently. One is handled by an inexact proximal point method and the other is solved directly. This feature is the major difference between the proposed method and some existing alternating direction-like methods. The convergence of the piPAD method is proved. Two examples of the modern convex optimization problem arising from engineering and information sciences, which can be reformulated into the encountered SVIs, are presented to demonstrate the applicability of the piPAD method. Also, some preliminary numerical results are reported to validate the feasibility and efficiency of the piPAD method.
Study on electric field in Au/CdZnTe/In detectors under high fluxes of X-ray and laser irradiation

We used simultaneous Pockels effect and photoconductivity measurements to study of processes in high-resistivity CdZnTe semiconductor X-ray and gamma ray detector material at steady state high flux conditions. We have proven, that with an appropriate choice of monochromatic laser light, the profile of the electric field is nearly the same as with a polychromatic X-ray source. We observed that the electric field is strongly deformed in the case of both above and below bandgap laser radiation. This leads to a decrease of the photocurrent when the sample is illuminated with above bandgap radiation. When below bandgap illumination is used the photocurrent values are not affected by electric field weakening. This is explained by increased filling of the midgap trap with trapped electrons leading to an increase of the lifetime.
Patterned growth of ZnO nanorods by micromolding of sol-gel-derived seed layer

An effective method for fabricating micropatterned ZnO nanorods without a catalyst via hydrothermal synthesis using a micromolding technique is presented. Micromolding of a sol-gel-derived seed layer was flawlessly accomplished by conformal contact of elastic mold with microscale pattern. The patterned growth of the nanorods over a large area of the preconfined seed layer was observed with a pattern feasibility attaining 1μm. The orientation of the resulting crystalline nanorods was observed to be normal to the seed layer while characteristic sizes of the nanorods did not show any dependences on the diameter of the seed particles. The presented synthetic process can provide a simpler and more inexpensive way for the fabrication of an array of one-dimensional nanostructures using a wet-chemical method.