Instytut Podstawowych Problemów Techniki
Polskiej Akademii Nauk

Pracownicy

dr hab. inż. Stanisław Tokarzewski

Zakład Biosystemów i Miękkiej Materii (ZBiMM)
Pracownia Fizyki Płynów Złożonych (PFPZ)
emeryt
telefon: (+48) 22 826 12 81 wewn.: 227
pokój: 323
e-mail:

Doktorat
1976 Ocena dynamicznych własności lepkosprężystych anizotropowych materiałów złożonych 
promotor -- prof. dr hab. inż. Stefan Zahorski, IPPT PAN
 
Habilitacja
2007-03-15 Multipoint continued fraction approach to the bounds on the effective transport coefficients of the phase media  

Ostatnie publikacje
1.  Tokarzewski S., Multipoint matrix Pad´e approximant bounds on effective anisotropic transport coefficients of two-phase media, ZEITSCHRIFT FUR ANGEWANDTE MATHEMATIK UND PHYSIK ZAMP, ISSN: 0044-2275, DOI: 10.1007/s00033-012-0214-z, Vol.64, pp.167-178, 2013

Streszczenie:
It is well known that a tensor Stieltjes function f represents an effective transport coefficient q of an inhomogeneous medium consisting of two isotropic components. In this paper, we investigate multipoint matrix Padé approximants to matrix expansions of f. We prove that matrix Padé ones to f estimate f from the top and below. Consequently the Padé approximants to q form upper and lower bounds on q. The inequalities for matrix Padé bounds on f and q are established. They reduce to the inequalities for scalar Padé ones Tokarzewski (ZAMP 61:773–780, 2010). As an illustrative example, matrix Padé estimates of an effective conductivity of a specially laminated two-phase medium are computed.

Słowa kluczowe:
Matrix Stieltjes functions, Matrix continued fractions, Effective transport coefficients, Composites, Porous materials, Bounds

Afiliacje autorów:
Tokarzewski S. - IPPT PAN
30p.
2.  Tokarzewski S., Wajnryb E., General inequalities for multipoint Padé approximants to a Stieltjes function expanded at real points, MATHEMATICAL INEQUALITIES AND APPLICATIONS, ISSN: 1331-4343, Vol.14, No.4, pp.977-988, 2011

Streszczenie:
In this paper we establish the general inequalities for diagonal and subdiagonal multipoint Pad´e approximants to a Stieltjes function f in terms of power expansion of f on the real line. The inequalities derived produce the best upper and lower bounds on f with respect to the given coefficients of Stieltjes series. As an example of applications sequences of upper and lower Pad´e bounds converging to the effective dielectric constant of a random array of spheres are evaluated.

Słowa kluczowe:
N -point Pad´e approximants, Stieltjes functions, continued fractions

Afiliacje autorów:
Tokarzewski S. - IPPT PAN
Wajnryb E. - IPPT PAN
25p.
3.  Tokarzewski S., Inequalities for bounds on effective transport coefficients of two-phase media from power expansions at real points, ZEITSCHRIFT FUR ANGEWANDTE MATHEMATIK UND PHYSIK ZAMP, ISSN: 0044-2275, DOI: 10.1007/s00033-009-0026-y, Vol.61, pp.773-780, 2010

Streszczenie:
The effective transport coefficient q of two-phase media is uniquely expressed by a special Stieltjes function f. In this paper, we incorporate into bounds on q, the power expansions of f available at a number of real points. To this end we apply the S-continued fraction technique developed in Baker (Essentials of Padé Approximants, Academic Press, New York, 1975) and Tokarzewski (IFTR Rep 4:3–171, 2005). Moreover, we establish the fundamental inequalities for S-bounds on q. As an example of an application the sequences of upper and lower S-bounds on the effective conductivity of a face-centered cubic lattice of spheres are evaluated.

Słowa kluczowe:
Stieltjes functions, S-continued fractions, Effective transport coefficients, Composites

Afiliacje autorów:
Tokarzewski S. - IPPT PAN
32p.
4.  Tokarzewski S., Magnus A., Gilewicz J., Estimation of a Stieltjes function expanded to Taylor series at complex conjugate points, JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS, ISSN: 0377-0427, Vol.233, No.3, pp.835-841, 200927p.
5.  Gilewicz J., Pindor M., Telega J.J., Tokarzewski S., N-point Padé approximants and two sided estimates of errors on the real axis for Stieltjes functions, JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS, ISSN: 0377-0427, DOI: 10.1016/j.cam.2003.12.051, Vol.178, pp.247-253, 2005

Streszczenie:
Upper and lower estimates of Stieltjes function by N-point Padé approximants can be obtained using the new general inequality reported by Tokarzewski et al. (Arch. Mech. 54 (2002) 141–153) and rigorously proved in the present paper. In addition, we prove that the multipoint Padé approximants to Stieltjes function are symmetric with respect to the order of choice of the considered points.

Słowa kluczowe:
N-point Padé approximants, Stieltjes functions

Afiliacje autorów:
Gilewicz J. - inna afiliacja
Pindor M. - inna afiliacja
Telega J.J. - IPPT PAN
Tokarzewski S. - IPPT PAN
6.  Gambin B., Gałka A., Telega J.J., Tokarzewski S., Influence of anisotropy induced by microcracks on effective elastic properties, ENGINEERING TRANSACTIONS (ROZPRAWY INŻYNIERSKIE), ISSN: 0867-888X, Vol.53, No.4, pp.409-420, 2005
7.  Gilewicz J., Pindor M., Telega J.J., Tokarzewski S., Continued fractions, two-point Padé approximants and errors in the Stieltjes case, JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS, ISSN: 0377-0427, DOI: 10.1016/S0377-0427(01)00538-6, Vol.145, No.1, pp.99-112, 2002

Streszczenie:
A Stieltjes function is expanded in mixed T- and S-continued fraction. The relations between approximants of this continued fraction and two-point Padé approximants are established. The method used by Gilewicz and Magnus (J. Comput. Appl. Math. 49 (1993) 79; Integral Transforms Special Functions 1 (1993) 9) has been adapted to obtain the exact relations between the errors of the contiguous two-point Padé approximants in the whole cut complex plane.

Słowa kluczowe:
Two-point Padé approximation, Stieltjes functions

Afiliacje autorów:
Gilewicz J. - inna afiliacja
Pindor M. - inna afiliacja
Telega J.J. - IPPT PAN
Tokarzewski S. - IPPT PAN
8.  Tokarzewski S., Telega J.J., S-Continued Fraction Method for the Investigation of a Complex Dielectric Constant of Two-Components Composite, Acta Applicandae Mathematicae, ISSN: 0167-8019, DOI: 10.1023/A:1005861519473, Vol.49, No.1, pp.55-83, 1997

Streszczenie:
The aim of this contribution is to examine the S-continued fraction method of obtaining bounds on the effective dielectric constant εe of a two-phase composite for the case where the dielectric coefficients ε1and ε2 of both components are either complex or real. The starting point for our study is a power expansion of εe(z) at(z)=0 (z)=ε2/ε1-1. The obtained S-continued fraction bounds have an interesting mathematical structure convenient for theoretical and numerical investigations of εe. They also agree with the earlier estimations reported by Bergman and Milton. Specific examples of calculation of bounds on εe by theS-continued fraction method are also provided.

Słowa kluczowe:
composite medium, bounds, dielectric constants, Stieltjes function

Afiliacje autorów:
Tokarzewski S. - IPPT PAN
Telega J.J. - IPPT PAN
9.  Tokarzewski S., Telega J.J., S-continued Fraction Representation for Effective Transport Coefficients of Two-phase Media, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.16, pp.1-58, 1995
10.  Tokarzewski S., Bławzdziewicz J., Andrianov I., Two-point Pade Approximants for Stieltjes Series, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.30, pp.1-17, 1993
11.  May S., Tokarzewski S., Zachara A., Cichocki B., Efektywna przewodność dwuskładnikowego kompozytu o regularnej dwuwymiarowej strukturze, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.24, pp.1-78, 1992
12.  Tokarzewski S., Ocena dynamicznych własności lepkosprężystych anizotropowych materiałów złożonych (Praca doktorska), Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.56, pp.1-93, 1975

Lista ostatnich monografii
1. 
Tokarzewski S., Multipoint continued fraction approach to the bounds on effective transport coefficients of two-phase media, Rozprawa habilitacyjna, IPPT Reports on Fundamental Technological Research, 4, pp.1-131, 2005

Abstrakty konferencyjne
1.  Gambin B., Tokarzewski S., Ivanova J., Bounds on strength tensor for piezoelectric composites, SolMech 2010, 37th Solid Mechanics Conference, 2010-09-06/09-10, Warszawa (PL), pp.32-33, 2010

Kategoria A Plus

IPPT PAN

logo ippt            ul. Pawińskiego 5B, 02-106 Warszawa
  +48 22 826 12 81 (centrala)
  +48 22 826 98 15
 

Znajdź nas

mapka
© Instytut Podstawowych Problemów Techniki Polskiej Akademii Nauk 2021