Wyniki wyszukiwania - Biblioteka Nauki

1

On some modified (0,....,m-2,m) interpolation

100%

Prasad J. , Jhunjhunwala N. , Katz R.

Demonstratio Mathematica

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2001

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tom Vol. 34, nr 1

199-204

EN

The problems of modified (0,1,... ,m-2,m) interpolation, m > 2, on Legendre abscissas are investigated here.

2

Off-diagonal multilinear interpolation between adjoint operators

100%

Grafakos L. , Lynch R. G.

Commentationes Mathematicae

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2015

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tom Vol 55, No. 1

17--22

EN

We extend a theorem by Grafakos and Tao on multilinear interpolation between adjoint operators [Multilinear interpolation between adjoint operators, J. Funct. Anal. 199 (2003), 379–385] to an off-diagonal situation. We provide an application.

3

Increasing resolution of digital images using edge-based approach

80%

Świerczyński Z. , Rokita P.

Opto-Electronics Review

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2008

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tom Vol. 16, No. 1

76-84

EN

This paper presents the results of our research aimed at obtaining new methods for increasing resolution of digital images giving better visual results. Classification of these methods and implementation of some algorithms is also shortly presented here. The main part of the paper presents modification and development of the new methods. Main new feature, which we added to the interpolation algorithms, consists in taking into consideration in the final image (i.e., after interpolation at high resolution) the edges detected in the original image (i.e., before interpolation). Summing an image and its properly processed edges in the interpolation process enables us to get final image characterized by better sharpness with simultaneous precise presentation of the image details interpolated to higher resolution.

4

Interpolated subspaces of exponential vectors of the unbounded operators in Banach spaces

80%

Dmytryshyn M. , Lopushansky O.

Demonstratio Mathematica

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2004

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tom Vol. 37, nr 1

149--158

EN

It is shown that the spectral subspaces of the unbounded operators in Ba-nach spaces and also their integer degrees can be described with help of interpolation. The spectral subspaces of operators are described on the basis of abstract Bernstein inequality. The results are applied to research of the root subspaces of regular elliptic operators in a bounded domains.

5

Partial retractions for weighted Hardy spaces

80%

Kisliakov S. , Xu Q.

Studia Mathematica

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2000

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tom 138

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nr 3

251-264

EN

Let 1 ≤ p ≤ ∞ and let $w_0, w_1$ be two weights on the unit circle such that $log(w_0w_1^{-1})∈ BMO$. We prove that the couple $(H_p(w_0), H_p(w_1))$ of weighted Hardy spaces is a partial retract of $(L_p(w_0), L_p(w_1))$. This completes previous work of the authors. More generally, we have a similar result for finite families of weighted Hardy spaces. We include some applications to interpolation.

6

Methods of modeling the power characteristics of wind turbines

80%

Jarmuda T.

Computer Applications in Electrical Engineering

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2016

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tom Vol. 14

393--406

EN

The work presents three methods of modeling the power characteristics of a wind turbine in the MATLAB & SIMULINK environment, that is – linear interpolation, nonlinear approximation, and linear approximation. Simulation tests were performed for two wind turbines: AH and AIRCON, with the nominal power of 10 kW. Calculations of the amount of electric energy generated by the above–mentioned types of wind turbines were performed for the constraint assumed (wind speed measurements in the south–eastern Poland for January and June 2014). The differences between the energy amounts calculated with the use of the three power characteristic modeling methods were determined. The results were summarized and final conclusions were formulated.

7

On interpolation in NEXT(KB.Alt(2))

80%

Kostrzycka Z.

Bulletin of the Section of Logic

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2018

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tom 47

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nr 3

EN

We prove that there is infinitely many tabular modal logics extending KB.Alt(2) which have interpolation.

8

Packing in Orlicz sequence spaces

80%

Rao M. M. , Ren Z. D.

Studia Mathematica

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1997

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tom 126

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nr 3

235-251

EN

We show how one can, in a unified way, calculate the Kottman and the packing constants of the Orlicz sequence space defined by an N-function, equipped with either the gauge or Orlicz norms. The values of these constants for a class of reflexive Orlicz sequence spaces are found, using a quantitative index of N-functions and some interpolation theorems. The exposition is essentially selfcontained.

9

On some generalization of box splines

80%

Wronicz Z.

Annales Polonici Mathematici

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1999

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tom 72

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nr 3

261-271

EN

We give a generalization of box splines. We prove some of their properties and we give applications to interpolation and approximation of functions.

10

Optimising ray tracing for visualisation of volumetric medical image data

80%

Lorang T. , Schuster E. , Gengler M. , Prinz M.

Machine Graphics and Vision

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1999

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tom Vol. 8, No. 4

691-697

EN

The presented optimizations provide an approach to fast rendering of medical volume data. They are based on the ray casting algorithm, which is substantially speeded up with regard to voxel addressing and interpolation.

11

A modified linear approximation for weakly singular integrals

80%

Nadir M.

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tom Vol. 9, nr 4

19--25

EN

In this work, we present a new approximation for a weakly singular integral, in particular Abel's integral. This approximation is based on the modification of the linear spline function, this one leads to eliminate the weak singularity. Noting that, it is clear that in the future we use this approximation for solving numerically all weakly singular integrals equations on an oriented smooth curve or on an interval.

12

Satellite image pansharpening by chrominance propagation combined with kernel interpolation

80%

Iwanowski M. , Huk A.

Machine Graphics and Vision

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2006

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tom Vol. 15, No. 3/4

429-438

EN

This paper describes a method for propagation-based spatial interpolation of missing color information in satellite images. Most of the land-observation satellites produce two types of imagery for every scene multispectral and panchromatic. The first kind is characterized by lower spatial resolution but higher spectral one, while the second is a graylevel image at higher resolution. In order to get full color visualization of a scene, the high-resolution panchromatic image must be combined with the low-resolution color information taken from multispectral bands. This process is called pansharpening. In this paper, a new method for pansharpening is proposed which combines chrominance propagation with kernel interpolation. Thanks to the propagation step, the method properly reconstructs color information and does not blur the edges on color channels.

13

OFDM Performance of Ultra Wideband in Wireless Body Area Network Channel

80%

Karan Y. , Şaylı O. , Kahveci S.

Acta Physica Polonica A

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2017

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tom 132

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nr 3

574-576

EN

Data transfer for health monitoring can be highly critical because of life dependency transmitted data. IEEE 802.15.6 is a standard for wireless body area network published in 2012 to satisfy the reliability which is required by health monitoring systems. Ultra wideband is one of proposed physical layer technologies specified in the wireless body area network standard which offers high bandwidth, low power, and low interference with other devices. Orthogonal frequency-division multiplexing is commonly used to transmit the data in many wireless communication standards due to its high spectral efficiency and immunity to the inter symbol interference. In this study, bit-error rate performance for orthogonal frequency-division multiplexing with different interpolation based least square channel estimation is given for wireless body area network channel model. OFDM symbol length and pilot length used in OFDM symbol is investigated in bit error rate - signal to noise ratio graphs.

14

Contribution of GIS in the Mapping, Interpolation and Modeling of Isohypses of the Pliocene Aquifuge of the Free Water Table of the Fez-Meknes Basin

80%

El Fakir R. , Mili E. M.

Ecological Engineering & Environmental Technology

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2022

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tom Vol. 23, iss. 5

272--284

EN

In order to model the water flow of the free Quaternary aquifer of the Fez-Meknes basin, it is essential to determine the precise geometric limits of the aquifer. Indeed, the characterization and representation of the underground structure of the Miocene marl top which forms the aquiclude of the aquifer, constitutes the fundamental step to study and understand its influence on the groundwater flow. This study is facilitated by the available data, which allow to represent the underground formations on isohypses maps. The data base is formed by reconnaissance drillings, and the extraction of marl altitudes from previous geological works. During this work the generation of the marl top elevation map was based on the test of four interpolation methods, which correspond to : Kriging, IDW method, Natural Neighbors, and Topo to Raster, in order to choose the most reliable and best suited to the study area. On the one hand, the calculation of the conformity index between the values measured in the field and the estimated values for each method was successively (0.9796, 0.9848, 0.9814, 0.9842). On the other hand the values of the root mean square error (RMSE) were successively (13.59, 7.42, 21.27, 14.01). The comparison of these results allowed us to choose the IDW interpolation as the most reliable and suitable to interpolate the top of the aquiclude of the free water table of the Fez Meknes basin with a compliance index the highest and a RMSE the lowest compared to other methods.

15

Determination and evaluation of spatio-temporal trends on the example of PM10 concentration in Poland (2000-2018)

80%

Jackowska M. , Fiedukowicz A. , Gąsiorowski J.

Polish Cartographical Review

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2021

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tom Vol. 53. No. 1

37--48

EN

. Increasing amounts of rapidly growing data are the driving force behind proposing and automating new processing, enabling the extraction of useful information from data. One of such possibilities is determining trends to consider in terms of time and space. Thus far, the analysis of these aspects has been separate and lacked automated tools. Therefore, the authors proposed, implemented, and tested a tool for analyzing spatio-temporal linear trends. The tool was tested on PM10 concentration data in the years 2000–2018. The results, presented as cartographic visualization, were then evaluated, both in terms of time and space. The proposed approach facilitates analyzing spatio-temporal trends and assessing their accuracy; it can be developed using other types of analyzed trends or considering additional factors that influence the trend by using cokriging.

16

Reduced data for curve modeling – applications in graphics, computer vision and physics

80%

Janik M. , Kozera R. , Kozioł P.

Advances in Science and Technology. Research Journal

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2013

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tom Vol. 7, nr 18

28--35

EN

In this paper we consider the problem of modeling curves in R n via interpolation with out apriori specified interpolation knots. We discuss two approaches to estimate missing knots{ti}mi=0 for non-parametric data(i.e.collection of points {qi}mi=0, where qiRn). The first approach (uniforme valuation) is based on blind guess in which knots {ˆti}mi=0 are chosen uniformly. The second approach (cumulative chord parameterization), incorporates the geometry of the distribution of data points.More precisely the difference ˆti+1−ˆti is equal to the Euclidean distance between data points qi+1 and qi. The second method partially compensates for the loss of the information carried by the reduced data. We also present the application of the above schemes for fitting non-parametric data in computer graphics (light-source motion rendering),in computer vision (image segmentation)and in physics (high velocity particles trajectory modeling).Though experiments are conducted for points in R2 and R3 the entire method is equally applicable in Rn.

17

The structure of the crust in TESZ area by kriging interpolation

80%

Majdański M.

Acta Geophysica

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2012

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tom Vol. 60, no. 1

59-75

EN

A precise 3D model of the crust is necessary to start any tectonic or geodynamic interpretation. It is also essential for seismic interpretations of structures lying below as well as for correct analysis of shallow structures using reflection seismics. During the last decades, a number of wide-angle refraction experiments were performed on the territory of central and eastern Europe (POLONAISE’97, CELEBRATION 2000, SUDETES 2003), resulting in many high quality 2D models. It is an interesting and complicated transition zone between Precambrian and Palaeozoic Platforms. This paper presents 3D model of the velocity distribution in the crust and upper mantle interpolated from 2D models of the structure along 33 profiles. The obtained model extends to a depth of 50 km and accurately describes the main features of the crustal structures of Poland and surrounding areas. Different interpolation techniques (Kriging, linear) are compared to assure maximum precision. The final model with estimated uncertainty is an interesting reference of the area for other studies.

18

An approach for electrical harmonic analysis based on interpolation DFT

80%

Jiao L. , Du Y.

Archives of Electrical Engineering

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2022

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tom Vol. 71, nr 2

445--454

EN

The discrete Fourier transform (DFT) is the main method of electrical harmonic analysis since it’s easily realized in an embedded system. But there were some difficulties in performing synchronized sampling. The spectral leakage caused by asynchronous sampling affects the accuracy of harmonics analysis. Using window functions and interpolation algorithms can improve the accuracy of harmonics analysis. An approach for electrical harmonic analysis based on the interpolation DFT was proposed. A window function reduces DFT leakage and the interpolation algorithm modifies the calculation results of frequency, amplitude and the initial phase angle. The simulation results indicate that, by using the interpolation DFT electrical harmonic analysis method based on the Hanning window or the Blackman window, the error of calculating amplitudes and frequencies is not greater than 0.5%.

19

$(H_p,L_p)$-type inequalities for the two-dimensional dyadic derivative

70%

Weisz F.

Studia Mathematica

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1996

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tom 120

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nr 3

271-288

EN

It is shown that the restricted maximal operator of the two-dimensional dyadic derivative of the dyadic integral is bounded from the two-dimensional dyadic Hardy-Lorentz space $H_{p,q}$ to $L_{p,q}$ (2/3 < p < ∞, 0 < q ≤ ∞) and is of weak type $(L_1,L_1)$. As a consequence we show that the dyadic integral of a ∞ function $f ∈ L_1$ is dyadically differentiable and its derivative is f a.e.

20

Two-dimensional EMD with shape-preserving spline interpolation

70%

Brown W. G. , Walt M. D. v. d.

Journal of Applied Analysis

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2023

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tom Vol. 29, nr 2

287--296

EN

Empirical mode decomposition (EMD) is a popular, user-friendly, data-driven algorithm to decompose a given (non-stationary) signal into its constituting components, utilizing spline interpolation. This algorithm was first proposed in 1998 in the one-dimensional setting, and it employed standard cubic spline interpolation. Since then, different two-dimensional extensions of EMD have been proposed. In this paper, we consider one of these two-dimensional extensions and adapt it to use a shape-preserving interpolation scheme based on quadratic B-splines, ensuring that monotonicity and concavity in the input data are preserved. Using multiple numerical experiments, we show that this new scheme outperforms the original EMD, both qualitatively and quantitatively.