bluuebunny/crossref_metadata_2025_split huggingface dataset:
Qualified Thresholds forWavelet Shrinkage
Authors: Boese F. G. 
Published: December 2005

AbstractOne of many method for noise reduction in measured data is the wavelet‐based Wavelet Shrinkage propagated by D. L. Donoho, I. M. Johnstone et al. since about 1990. A crucial step within this approach is the setting of the treshold which decides whether a wavelet coefficient is considered as noise or as data. We propose an one‐paramerter family of thresholds. The parameter is the probability of making a false decision. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Prediction of Extreme Ship Motions in Irregular Waves
Authors: Kreuzer Edwin , Sichermann Wolfgang 
Published: December 2005

AbstractThe occurrence of indirectly excited large amplitude roll motions of ships is investigated under the influence of a time‐varying righting lever curve in waves. In order to account for the irregular character of ocean waves appropriately, the ship motions are described within the framework of nonlinear dynamics and stochastic process theory. The analysis of roll motions in regular waves provides a qualitative understanding of the occurrence of unpredictable large amplitude roll motions as observed in ocean waves. However, quantitative information on the rolling behavior in irregular waves may be retrieved only from a probabilistic analysis. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Vibration of a Beam on Random and Microperiodic Subsoil Caused by Moving Load
Authors: Mazur‐Sniady K. , Rystwej A. , Sniady P. 
Published: December 2005

AbstractThe subject of the analysis is a vibration problem of an infinitive beam resting on a foundation with periodic and stochastic parameters under a stochastic moving load. The problem is solved using the Tolerance Averaging Approximation procedure and also concept of a stochastic dynamic influence function. In this way we obtained an effective solution which may be applied in the railway engineering. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Estimation of the Bar Structure Safety with Respect to the Plastic Reserve of Material and Random Physical and Geometrical Parameters
Authors: Sieniawska Roza , Wysocka Alina , Zukowski Stanislaw 
Published: December 2005

AbstractAn approach for estimation of the bar structure safety is presented. It is assumed that the structure is made of an elasticperfectly plastic material, with random lengths of the elements, random dimensions of the cross‐sections and material parameters, is subjected to the dead and variable live loads and works in uniaxial state of stresses. It is also assumed that the probabilistic characteristics of the random parameters are known and that all random variables are mutually independent. As the structure safety measure the reliability index is regarded. A new formula for reliability index estimation is proposed. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Sensitivity analysis of uncertain structures subject to stochastic load in the framework of SFEM
Authors: Zielichowski‐Haber W. 
Published: December 2005

AbstractIn the paper, sensitivity analysis of linear system with uncertain parameters subject to stochastic stationary and non stationary stochastic point process is presented. The proposed approach for the design sensitivity of probabilistic system is formulated in the framework of Stochastic FEM on the basis of the concept of a sensitivity random influence vector in the context of correlation theory i.e. restricted to the probabilistic moments of second order. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
An Extension of the Conjugate Directions Method With Orthogonalization to Large‐Scale Problems With Bound Constraints
Authors: Boudinov Edouard , Manevich Arkadiy 
Published: December 2005

AbstractIn our previous works a new method of conjugate directions for large‐scale unconstrained minimization problems has been presented [1, 2]. In the paper this algorithm is extended to minimization problems with bound constraints. Because the linear minimization along the newly found conjugate vector is not needed for constructing the next conjugate vector and one arbitrarily step‐size (not necessarily the optimal one) is calculated along this conjugate direction, we are able to incorporate naturally the bound constraints into the algorithm. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Parameter estimation for forward Kolmogorov equation with application to nonlinear exchange rate dynamics
Authors: Jäger Simon , Kostina Ekaterina 
Published: December 2005

AbstractDiffusion processes are widely used for mathematical modeling in finance e.g. in modeling foreign exchange rates. Stochastic differential equations describing diffusion processes are linked directly to the forward Kolmogorov equations. In order to calibrate the models, efficient algorithms identifying the system parameters are in demand. Taking into account nonlinear effects in volatility and drift and dependence on observed economical data, which are not directly modeled, one obtains problems which cannot be treated by standard numerical methods. The coefficients are rapidly oscillatory and strong instabilities may arise. To handle these problem we develop special numerical methods, which are used to simulate the nonlinear dynamics of exchange rates depending on economic data. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Multicriterion optimization of hybrid composite plates with various supports under transverse load
Authors: Kasprzak Jakub , Ostwald Marian 
Published: December 2005

AbstractIn this paper applications of multicriteria optimization to design hybrid laminates is shown. In the considered numerical example, the obtained preferred solution is 30% heavier than Carbon/Epoxy laminate and use a third of the more expensive material. Moreover, a small number of layers is needed to build an optimal solution. In the case of scalar optimization three layers are required. In the case of bicriteria optimization one E‐Glass/Epoxy layer placed between four Carbon/Epoxy layers is enough to build an optimal laminate. Two criteria may lead to a set of preferred equal solutions. Thus, connection of Pareto concept with a lexicographic order by introduction of an additional criterion is useful for ordering them. A similar approach may be used for designing hybrid laminates with a requirement of a compromise between the stiffness and cost of a plate. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Bicriterion optimization of cold‐formed thin‐walled beams with I‐type shape
Authors: Rodak Marcin , Ostwald Marian 
Published: December 2005

AbstractThe work is devoted to bi‐criterion optimization of thin‐walled cold‐formed beams under pure bending. The first objective function is the area of a beam cross‐section and the maximum deflection of a beam is taken as the second one. The strength and stability constraints in bi‐objective optimization problem are taken into account and formulated analytically. Some results of numerical calculations are presented in the form of the tables. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A Boundary Integral Equation Method for the Numerical Modeling of Particles of Arbitrary Shape
Authors: Illyashenko‐Raguin Lyudmyla , Arbenz Peter 
Published: December 2005

AbstractA variant of the Boundary Integral Equation method for the numerical study of dielectric particles has been developed. In addition to the advantages of the classical BEI method, the proposed modification allows to study the particles of almost arbitrary shape, including the accurate numerical treatment of the integral equation singularities and geometrical singularities of the particle boundary. It guarantees the fast and accurate solution with small computer resources. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Multiscale Flow Simulation by Adaptive Finite Volume Particle Methods
Authors: Jürgens Markus 
Published: December 2005

AbstractWe present a discretisation of parabolic problems in the time direction based on piecewise linear wavelets. This discretisation of the solution admits a sparse representation, i.e. few coef.cients have to be stored to achieve a reasonable close approximation to the exact solution. To demonstrate the advantages of this method we provide numerical experiments for Tikhonov regularisation of the inverse heat equation. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Wavelets on the 3–dimensional Ball
Authors: Michel V. 
Published: December 2005

AbstractIn this article wavelets on a ball in ℝ3are introduced. Corresponding properties like an approximate identity and decomposition/reconstruction (scale step property) are proved. The advantage of this approach compared to a classical Fourier analysis in orthogonal polynomials is a better localization of the used ansatz functions. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Based on Walsh packet parametric identification technique for dynamic systems
Authors: Napiorkowska‐Alykow Magdalena , Glabisz Wojciech 
Published: December 2005

AbstractThe article presents an application of wavelet packet analysis in the parametric identification of discrete dynamic systems. The Walsh packet basis and their operational matrixes enables reduction of row derivatives, which are necessary in the procedure of identification of signal derivatives for systems, which are analyzed, and also enable algebraization their mathematical describe, what in combination with wavelet packet analysis with Haar filter properties decided on a great efficiency of parametric identification of linear systems procedure, which is built on wavelet packet analysis. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Method of order 1 + $\sqrt 2$ for the solution of nonlinear equations with Hölder continuous divided differences
Authors: Shakhno S. M. 
Published: December 2005

AbstractWe study an iterative method with order 1 + $\sqrt 2$ for solving nonlinear operator equations in Banach spaces. We present the received new results of local convergence, when the first‐order divided differences of a nonlinear operator are Hölder continuous. Method needs almost the same number of computations as the classical Secant method, but has a higher order of convergence. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The relationship between the models of perturbed Newton iterations, with applications
Authors: Cătinaş Emil 
Published: December 2005

AbstractThe quasi‐Newton method and the inexact Newton method are classical models of Newton iterates which take into account certain error terms. We have recently introduced the inexact perturbed Newton method, which takes into account all the possible sources of perturbations. We show that these models are in fact equivalent, in the sense that each one may be used to characterize the high convergence orders of the other two. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A New Eigenvalue Localization Theorem via Graph Theory
Authors: Cvetković Ljiljana , Kostić Vladimir 
Published: December 2005

AbstractWe give a generalization of a well‐known result of Brualdi concerning eigenvalue localization and compare this generalization with related results in this area. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Die beschleunigte Ritz‐Iteration im Eigenwertalgorithmus ECP
Authors: Falk S. , Wagner N. 
Published: December 2005

AbstractDie Eigenwerte einer Polynommatrix werden parallel und in beliebiger Reihenfolge aus einer skalaren Gleichung iterativ berechnet und eingeschlossen. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Using Core Formulations for Ill‐posed Linear Systems
Authors: Sima Diana M. , Van Huffel Sabine 
Published: December 2005

AbstractWe investigate the application of core problem formulations to the context of ill‐posed linear algebraic systems. We note that in order to impose regularization on such systems by using core formulations, one is lead to a technique similar to the Truncated (Total) Least Squares method. Choosing an appropriate truncation level from given data can be made efficient by incorporating the truncation level decision as a stopping criterion into a partial bidiagonalization algorithm. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Relaxed Krylov subspace approximation
Authors: Simoncini Valeria , Szyld Daniel B. 
Published: December 2005

AbstractRecent computational and theoretical studies have shown that the matrix‐vector product occurring at each step of a Krylov subspace method can be relaxed as the iterations proceed, i.e., it can be computed in a less exact manner, without degradation of the overall performance. In the present paper a general operator treatment of this phenomenon is provided and a new result further explaining its behavior is presented. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Coupled Partial Differential Equations in Fuel Cell Models
Authors: Heidebrecht Peter , Sundmacher Kai 
Published: December 2005

AbstractMathematical models play a vital role in fuel cell development. Some of the aspects treated with the help of models are the analysis of steady state and transient system behaviour during regular operation or start‐up and shut‐down, optimisation of system design and operating conditions and failure detection by online observation. In this contribution, we present some typical equations for high temperature fuel cell models and demonstrate their numerical treatment. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The perturbation index of linear PDAEs with a hyperbolic part
Authors: Rang Joachim , Angermann Lutz 
Published: December 2005

AbstractFor numerous problems in science and engineering a refined modelling approach leads to initial‐boundary value problems for partial differential‐algebraic equations (PDAEs). A perturbation index of the variational formulation of the PDAE is introduced. As examples, the compressible Navier–Stokes equations and a model problem from MHD are considered. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Multirate methods for the transient analysis of electrical circuits
Authors: Verhoeven A. , El Guennouni A. , ter Maten E. J. W. , Mattheij R. M. M. 
Published: December 2005

AbstractMultirate integration is an important tool to increase the speed of the transient analysis of circuits. This paper shows an approach for the “Compound‐Fast” multirate algorithm how to control the errors at the coarse and the refined time‐grid by means of the independent stepsizes of these grids. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On Discrete Korn's Inequality for some Nonconforming Finite Element Approaches to Linear Elasticity
Authors: Attia Frank S. , Starke Gerhard 
Published: December 2005

AbstractThe role of the discrete Korn's inequality for some nonconforming .nite element approaches to linear elasticity is discussed. Such methods enable uniform approximation in the incompressible limit and may be used in combination with a standard displacement‐based variational principle or with a least‐squares mixed formulation. A proof of the discrete Korn's inequality for a .nite element space recently proposed by Mardal, Tai and Winther is sketched. Numerical results illustrate the performance of these MTW elements for nearly incompressible linear elasticity. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Stabilized finite element schemes for generalized Oseen systems
Authors: Bause Markus 
Published: December 2005

AbstractIn recent works [1, 2], advanced approximation schemes for the numerical calculation of compressible viscous flow were developed, analyzed theoretically and applied successfully to benchmark problems. These methods are based on splitting the Poisson–Stokes system (1.1) describing the motion of a viscous compressible fluid into a generalized Oseen problem for the velocity and a hyperbolic transport equation for the density. Highly refined finite element techniques were proposed for the numerical solution of these separated subproblems of simpler structure; cf. [2]. In this paper, error estimates for a SUPG/(PSPG) and grad‐div stabilized finite element approximation of the generalized Oseen problems that arise in the course of the splitting procedure are presented. LBB‐stable pairs of finite element spaces are used for velocity and pressure. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Equilibrium shapes of a ferrofluid drop
Authors: Lavrova O. , Polevikov V. , Tobiska L. 
Published: December 2005

AbstractA numerical solution strategy for calculating equilibrium free surfaces of a ferrofluid drop under the action of uniform magnetic fields is proposed. Based on this strategy, drop shapes of nonlinear magnetisable fluids are obtained numerically in a wide range of field intensities and compared with existing theoretical results. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Numerical and Stability Aspects of Non‐Newtonian Fluid Flow
Authors: Scurtu Nicoleta , Bänsch Eberhard 
Published: December 2005

AbstractThis paper is concerned with nonlinear rheological fluids of Oldroyd type. We present a (formal) stability analysis of the corresponding system of equations, showing stability limits on the Weißenberg number in certain cases. Moreover, we introduce a numerical method for solving the full time‐dependent Oldroyd system based on the finite element spatial discretization and on the fractional step θ‐scheme time approximation. Numerical solutions are presented for two well known benchmark problems: the lid driven cavity and the four‐to‐one planar contraction. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Tuning the Acid/Base Surface Character of Carbonaceous Materials by Means of Cold Plasma Treatments
Authors: Favia Pietro , De Vietro Nicoletta , Di Mundo Rosa , Fracassi Francesco , d'Agostino Riccardo 
Published: December 2005

AbstractSummary: Carbonaceous materials, in the form of flat graphite slabs and carbon black granules, are surface‐modified in radio frequency (RF, 13.56 MHz) glow discharges fed with NH3/O2 mixtures at different power values, in order to graft oxygen‐containing and/or nitrogen‐containing chemical groups. In this way, it is possible to adjust the acid/base character of the material surfaces in a predictable way, as a function of the feed composition and of the power. A plasma reactor equipped with a rotating vacuum chamber and internal glass wings is used to keep the granular materials homogeneously stirred and to modify the surface of both graphite slabs and carbon black granules. The chemical modifications have been evaluated using X‐ray photoelectron spectroscopy. Water contact angle measurements have been carried out on flat graphite, with water solutions at different pH, in order to study the acid/base character imparted to the functionalized surface. Scanning electron microscopy analysis has been performed to check the effects of plasma treatments on the morphology of the substrates.SEM images of an untreated CB granule (left) and the same granule after 20 min of a O2‐plasma treatment (right).magnified imageSEM images of an untreated CB granule (left) and the same granule after 20 min of a O2‐plasma treatment (right).
The role of a conserved histidine–tyrosine interhelical interaction in the ion channel domain of δ‐endotoxins fromBacillus thuringiensis
Authors: Seale Jeffrey W. 
Published: December 2005

AbstractThe δ‐endotoxin proteins are produced byBacillus thuringiensisduring the sporulation phase of its life cycle. These proteins exhibit insecticidal activity through receptor‐mediated ion channel formation. The mode of action of these proteins requires the conversion of the protein from a water‐soluble conformation to a membrane‐inserted conformation. While there is X‐ray structure information for the soluble protein, no detailed structure exists for the membrane‐inserted protein. However, based on peptide studies, an umbrella model for the membrane‐inserted state has been proposed. Here, we investigated the role of a conserved hydrogen bond interaction between two helices that are suggested to undergo a large conformational change upon membrane insertion. Mutation of either the histidine or the tyrosine resulted in a protein that has significantly reduced bioactivity, increased overall flexibility, and significantly reduced stability. These data highlight an important role for this interaction in the overall stability of the protein. Additionally, the conservation of histidine and tyrosine in these positions may suggest a functional role for the interaction in the conformational switching from soluble to membrane protein. Proteins 2006. © 2005 Wiley‐Liss, Inc.
Assessing a novel approach for predicting local 3D protein structures from sequence
Authors: Benros Cristina , de Brevern Alexandre G. , Etchebest Catherine , Hazout Serge 
Published: December 2005

AbstractWe developed a novel approach for predicting local protein structure from sequence. It relies on the Hybrid Protein Model (HPM), an unsupervised clustering method we previously developed. This model learns three‐dimensional protein fragments encoded into a structural alphabet of 16 protein blocks (PBs). Here, we focused on 11‐residue fragments encoded as a series of seven PBs and used HPM to cluster them according to their local similarities. We thus built a library of 120 overlapping prototypes (mean fragments from each cluster), with good three‐dimensional local approximation, i.e., a mean accuracy of 1.61 Å Cα root‐mean‐square distance. Our prediction method is intended to optimize the exploitation of the sequence‐structure relations deduced from this library of long protein fragments. This was achieved by setting up a system of 120 experts, each defined by logistic regression to optimize the discrimination from sequence of a given prototype relative to the others. For a target sequence window, the experts computed probabilities of sequence‐structure compatibility for the prototypes and ranked them, proposing the top scorers as structural candidates. Predictions were defined as successful when a prototype <2.5 Å from the true local structure was found among those proposed. Our strategy yielded a prediction rate of 51.2% for an average of 4.2 candidates per sequence window. We also proposed a confidence index to estimate prediction quality. Our approach predicts from sequence alone and will thus provide valuable information for proteins without structural homologs. Candidates will also contribute to global structure prediction by fragment assembly. Proteins 2006. © 2005 Wiley‐Liss, Inc.
Locally defined protein phylogenetic profiles reveal previously missed protein interactions and functional relationships
Authors: Kim Yohan , Subramaniam Shankar 
Published: December 2005

AbstractPhylogenetic profiles encode patterns of presence or absence of genes across genomes, and these profiles can be used to assign functional relationships to nonhomologous pairs of proteins (Pellegrini et al., Proc Natl Acad Sci USA 1999;96:4284–4288). Although it is well known that many proteins were created from combinations of domains, most of the existing implementations of phylogenetic profiles do not consider this fact. Here, we introduce an extension that considers the multidomain nature of proteins and test the method against the known interaction data sets. Whereas earlier implementations associated one entire sequence with one protein phylogenetic profile (Single‐Profile), our method instead breaks the sequence into a set of segments of predetermined size and constructs a separate profile for each segment (Multiple‐Profile). The results show that the Multiple‐Profile method performs as well as the Single‐Profile method. However, the two methods share, surprisingly, a small fraction of their predictions, indicating that the Multiple‐Profile method can detect known interactions missed by the Single‐Profile method. Thus, the Multiple‐Profile method can be used with other methods to determine functional relationships on a genome scale with wider coverage. Proteins 2006. © 2005 Wiley‐Liss, Inc.