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  • 51.
    Bergh, Jöran
    et al.
    Chalmers University of Technology, Department of Mathematics.
    Burenkov, Victor
    Department of Differential Equations and Functional Analysis, Russian Peoples' Friendship University.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Best constants in reversed Hardy's inequalities for quasimonotone functions1994Ingår i: Acta Scientarum Mathematicarum, ISSN 0001-6969, Vol. 59, nr 1-2, s. 221-239Artikel i tidskrift (Refereegranskat)
  • 52.
    Bergh, Jöran
    et al.
    Chalmers University of Technology, Department of Mathematics.
    Burenkov, Victor
    Department of Differential Equations and Functional Analysis, Russian Peoples' Friendship University.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    On some sharp reversed Hölder and Hardy type inequalities1994Ingår i: Mathematische Nachrichten, ISSN 0025-584X, E-ISSN 1522-2616, nr 169, s. 19-29Artikel i tidskrift (Refereegranskat)
  • 53.
    Blahota, I.
    et al.
    Institute of Mathematics and Computer Sciences, College of Nyíregyháza, Nyíregyháza, Hungary.
    Nagy, K.
    Institute of Mathematics and Computer Sciences, College of Nyíregyháza, Nyíregyháza, Hungary.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper. UiT the Arctic University of Norway, Narvik, Norway.
    Tephnadze, G.
    School of IT, Engineering and Mathematics, IV, University of Georgia, Tbilisi, Georgia.
    A sharp boundedness result for restricted maximal operators of Vilenkin–Fourier series on martingale Hardy spaces2019Ingår i: Georgian Mathematical Journal, ISSN 1072-947X, E-ISSN 1572-9176, Vol. 26, nr 3Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The restricted maximal operators of partial sums with respect to bounded Vilenkin systems are investigated. We derive the maximal subspace of positive numbers, for which this operator is bounded from the Hardy space H p {H-{p}} to the Lebesgue space L p {L-{p}} for all 0 < p ≤ 1 {0<p\leq 1}. We also prove that the result is sharp in a particular sense. 

  • 54.
    Blahota, I.
    et al.
    Institute of Mathematics and Computer Sciences, University of Nyìıregyhàza.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Tephnadze, George
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Two-sided Estimates of the Lebesgue Constants with respect to Vilenkin Systems and Applications2018Ingår i: Glasgow Mathematical Journal, ISSN 0017-0895, E-ISSN 1469-509X, Vol. 60, nr 1, s. 17-34Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, we derive two-sided estimates of the Lebesgue constants for bounded Vilenkin systems, we also present some applications of importance, e.g., we obtain a characterization for the boundedness of a subsequence of partial sums with respect to Vilenkin–Fourier series of H1 martingales in terms of n's variation. The conditions given in this paper are in a sense necessary and sufficient.

  • 55.
    Blahota, István
    et al.
    Institute of Mathematics and Computer Sciences, College of Nyíregyháza.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Tephnadze, George
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    On the Nörlund means of Vilenkin-Fourier series2015Ingår i: Czechoslovak Mathematical Journal, ISSN 0011-4642, E-ISSN 1572-9141, Vol. 65, nr 4, s. 983-1002Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We prove and discuss some new (H p ,L p )-type inequalities of weighted maximal operators of Vilenkin-Nörlund means with non-increasing coefficients {q k : k ⩾ 0}. These results are the best possible in a special sense. As applications, some well-known as well as new results are pointed out in the theory of strong convergence of such Vilenkin-Nörlund means. To fulfil our main aims we also prove some new estimates of independent interest for the kernels of these summability results.In the special cases of general Nörlund means t n with non-increasing coefficients analogous results can be obtained for Fejér and Cesàro means by choosing the generating sequence {q k : k ⩾ 0} in an appropriate way.

  • 56.
    Burtseva, Evgeniya
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Lundberg, Staffan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper. UiT, The Arctic University of Norwa.
    Samko, Natasha
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Multi–dimensional Hardy type inequalities in Hölder spaces2018Ingår i: Journal of Mathematical Inequalities, ISSN 1846-579X, E-ISSN 1848-9575, Vol. 12, nr 3, s. 719-729Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Most Hardy type inequalities concern boundedness of the Hardy type operators in Lebesgue spaces. In this paper we prove some new multi-dimensional Hardy type inequalities in Hölder spaces.

  • 57. Burtseva, Evgeniya
    et al.
    Lundberg, Staffan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Samko, Natasha
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Potential type operators in PDEs and their applications2017Ingår i: AIP Conference Proceedings, ISSN 0094-243X, E-ISSN 1551-7616, Vol. 1798, artikel-id 020178Artikel i tidskrift (Refereegranskat)
    Abstract [en]

     We prove the boundedness of Potential operator in weighted generalized Morrey space in terms of Matuszewska-Orlicz indices of weights and apply this result to the Hemholtz equation in r3 with a free term in such a space. We also give a short overview of some typical situations when Potential type operators arise when solving PDEs.

  • 58. Bylund, Nicklas
    et al.
    Byström, Johan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Persson, Lars-Erik
    Reiterated homogenization with applications to autopart construction2001Ingår i: ICCE 8: Eight Annual International Conference on Composites Engineering / [ed] David Hui, 2001, s. 31-34Konferensbidrag (Refereegranskat)
  • 59.
    Byström, Johan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Jekabsons, Normunds
    Persson, Lars-Erik
    A comparison of different homogenization models and experimental results1999Ingår i: ICCE 6: Sixth Annual International Conference on Composites Engineering / [ed] David Hui, 1999, s. 97-98Konferensbidrag (Refereegranskat)
  • 60.
    Byström, Johan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Persson, Lars-Erik
    Random versus periodic cells in homogenization2002Ingår i: ICCE 9: Ninth Annual International Conference on Composites Engineering / [ed] David Hui, 2002, s. 83-84Konferensbidrag (Refereegranskat)
  • 61.
    Byström, Johan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Persson, Lars-Erik
    Tillämpad matematik: en populär introduktion för lärare och ingenjörer2004Ingår i: Kvinnor och matematik : konferens den 12-14 april 2002: konferensrapport / [ed] Barbro Grevholm; Lisbeth Lindberg, Kristianstad: Högskolan Kristianstad , 2004, s. 37-48Konferensbidrag (Övrigt vetenskapligt)
  • 62.
    Byström, Johan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Persson, Lars-Erik
    Jekabsons, Normunds
    Luleå tekniska universitet.
    Varna, Janis
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Using reiterated homogenization for stiffness computation of woven composites1998Ingår i: ICCE 5: Fifth International Conference on Composites Engineering / [ed] David Hui, 1998, s. 133-134Konferensbidrag (Refereegranskat)
  • 63. Börjesson, Per Ola
    et al.
    Feichtinger, Hans G
    NUHAG (Numerical Harmonic Analysis Group), Dept. of Mathematics, University of Vienna.
    Grip, Niklas
    Isaksson, Mikael
    Telia Research AB.
    Kaiblinger, Norbert
    NUHAG (Numerical Harmonic Analysis Group), Dept. of Mathematics, University of Vienna.
    Ödling, Per
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    A low-complexity PAR-reduction method for DMT-VDSL1999Ingår i: Proceedings of the 5th International Symposium on Digital Signal Processing for Communication Systems: DSPCS'99, Perth, Australia, Feb. 1999, 1999, s. 164-169Konferensbidrag (Refereegranskat)
    Abstract [en]

    DMT-VDSL signals have a high peak-to-average power ratio (PAR). In the transmitters, the PAR governs the necessary resolution of the digital-to-analog converter (DAC) and is an important factor for the power consumption of the line-driver. Aiming at implementation in a specific system, we propose a low complexity PAR-reduction method based on the iterative algorithm derived in [5, 20, 24, 25]. We maintain good performance while stressing a straigthforward and low-complex implementation. Key elements of the method are: low latency; no loss in data rate; precalculated and stored peak-cancellation waveform; and bit-shifts (multiplication with powers of two) replacing the scaling of the waveform. Computer simulations show that, for a DMT frame length of 4096 samples and a frame clip rate of 10-4, the PAR can be reduced about 1.5 to 2.0 dB, depending on the number of peaks cancelled. When multiplication is replaced by bit-shifts, the reduction is still 1.5-1.7 dB.

  • 64.
    Carro, Maria J.
    et al.
    Department of Applied Mathematics and Analysis, University of Barcelona.
    Ericsson, Stefan
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Real interpolation for divisible cones1999Ingår i: Proceedings of the Edinburgh Mathematical Society, ISSN 0013-0915, E-ISSN 1464-3839, Vol. 42, nr 2, s. 285-304Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We give necessary and sufficient conditions on a general cone of positive functions to satisfy the Decomposition Property (DP) introduced in [5] and connect the results with the theory of interpolation of cones introduced by Sagher [9]. One of our main result states that if Q satisfies DP or equivalently is divisible, then for the quasi-normed spaces E0 and E1, According to this formula, it yields that the interpolation theory for divisible cones can be easily obtained from the classical theory

  • 65.
    Carro, Maria J.
    et al.
    Departamento de Matemàtica, Aplicada i Anàlisi, Universitat de Barcelona.
    Ericsson, Stefan
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    S-divisibility property and a Holmstedt type formula1999Ingår i: Journal of Approximation Theory, ISSN 0021-9045, E-ISSN 1096-0430, Vol. 98, nr 1, s. 1-24Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Given a conePof positive functions and an operatorS: →Pwith an additive group, we extend the concept ofK-divisibility to get some new formulas for theK-functional of finite families of lattices. Applications are given in the setting of rearrangement invariant spaces and weighted Lorentz spaces. As a consequence of our results, we also obtain a generalized Holmstedt formula due to Asekritova

  • 66.
    Carro, Maria J.
    et al.
    Departamento de Matemàtica, Aplicada i Anàlisi, Universitat de Barcelona.
    Nikolova, Ljudmila I.
    Department of Mathematics, Sofia University.
    Peetre, Jaak
    Department of Mathematics, University of Lund.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Some real interpolation methods for families of Banach spaces: a comparison1997Ingår i: Journal of Approximation Theory, ISSN 0021-9045, E-ISSN 1096-0430, Vol. 89, nr 1, s. 26-57Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We consider certain real interpolation methods for families of Banach spaces. We also define some new such methods obtained by passing to the limit in the constructions of Sparr and Cobos-Peetre. The relations between all these methods are studied. Characterizations of minimal and maximal spaces are obtained. Some concrete examples as well as sharp estimates of the corresponding operator norms are also exhibited.

  • 67.
    Carro, Maria J.
    et al.
    University of Barcelona.
    Nikolova, Ludmila
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Norms of interpolation operators controlled by the Dicesar function2000Ingår i: Function spaces and applications / [ed] David E. Edmunds, New Delhi: University of Dehli , 2000, s. 44-59Konferensbidrag (Refereegranskat)
  • 68.
    Chechkin, G. A.
    et al.
    Department of Differential Equations, Faculty of Mechanics and Mathematics, Moscow Lomonosov State University.
    Koroleva, Yulia O.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    On the precise asymptotics of the constant in Friedrich's inequality for functions vanishing on the part of the boundary with microinhomogeneous structure2007Ingår i: Journal of inequalities and applications (Print), ISSN 1025-5834, E-ISSN 1029-242XArtikel i tidskrift (Refereegranskat)
    Abstract [en]

    We construct the asymptotics of the sharp constant in the Friedrich-type inequality for functions, which vanish on the small part of the boundary Γ1ɛ. It is assumed that Γ1ɛ consists of (1/δ)n-1 pieces with diameter of order O(ɛδ). In addition, δ=δ(ɛ) and δ→0 as ɛ→0.

  • 69.
    Chechkin, G.A.
    et al.
    Department of Mechanics and Mathematics, Moscow State University.
    Koroleva, Yulia O.
    Meidell, Annette
    Narvik University College, 8505 Narvik, Norway.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    On the Friedrichs inequality in a domain perforated aperiodically along the boundary: Homogenization procedure. Asymptotics for parabolic problems2009Ingår i: Russian journal of mathematical physics, ISSN 1061-9208, E-ISSN 1555-6638, Vol. 16, nr 1, s. 1-16Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper is devoted to the asymptotic analysis of functions depending on a small parameter characterizing the microinhomogeneous structure of the domain on which the functions are defined. We derive the Friedrichs inequality for these functions and prove the convergence of solutions to corresponding problems posed in a domain perforated aperiodically along the boundary. Moreover, we use numerical simulation to illustrate the results.

  • 70.
    Chechkin, G.A.
    et al.
    Department of Differential Equations, Faculty of Mechanics and Mathematics, Moscow Lomonosov State University.
    Koroleva, Yulia
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Wall, Peter
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    On spectrum of the Laplacian in a circle perforated along the boundary: application to a Friedrichs-type inequality2011Rapport (Övrigt vetenskapligt)
  • 71.
    Chechkin, Gregory
    et al.
    Moscow Lomonosov State University.
    Koroleva, Yulia
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Wall, Peter
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    A new weighted Friedrichs-type inequality for a perforated domain with a sharp constant2011Ingår i: Eurasian Mathematical Journal, ISSN 2077-9879, Vol. 2, nr 1, s. 81-103Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We derive a new three-dimensional Hardy-type inequality for a cube for the class of functions from the Sobolev space $H^1$ having zero trace on small holes distributed periodically along the boundary. The proof is based on a careful analysis of the asymptotic expansion of the first eigenvalue of a related spectral problem and the best constant of the corresponding Friedrichs-type inequality.

  • 72.
    Chechkin, Gregory
    et al.
    Department of Differential Equations, Faculty of Mechanics and Mathematics, Moscow Lomonosov State University.
    Koroleva, Yulia
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Wall, Peter
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    On spectrum of the Laplacian in a circle perforated along the boundary: Application to a Friedrichs-type inequality2011Ingår i: International Journal of Differential Equations, ISSN 1687-9643, E-ISSN 1687-9651, Vol. 2011, artikel-id 619623Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper we construct and verify the asymptotic expansion for the spectrum of a boundary-value problem in a unit circle periodically perforated along the boundary. It is assumed that the size of perforation and the distance to the boundary of the circle are of the same smallness. As an application of the obtained results the asymptotic behavior of the best constant in a Friedrichs-type inequality is investigated.

  • 73.
    Cizmesija, Alexandra
    et al.
    Department of Mathematics, University of Zagreb.
    Pecaric, Josip
    Faculty of Textile Technology, University of Zagreb.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    On strengthened Hardy and Pólya–Knopp's inequalities2003Ingår i: Journal of Approximation Theory, ISSN 0021-9045, E-ISSN 1096-0430, Vol. 125, nr 1, s. 74-84Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper we prove a strengthened general inequality of the Hardy–Knopp type and also derive its dual inequality. Furthermore, we apply the obtained results to unify the strengthened classical Hardy and Pólya–Knopp's inequalities deriving them as special cases of the obtained general relations. We discuss Pólya–Knopp's inequality, compare it with Levin–Cochran–Lee's inequalities and point out that these results are mutually equivalent. Finally, we also point out a reversed Pólya–Knopp type inequality.

  • 74.
    Cizmesija, Alexandra
    et al.
    Department of Mathematics, University of Zagreb.
    Pecaric, Josip
    Faculty of Textile Technology, University of Zagreb.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    On strengthened weighted Carleman´s inequality2003Ingår i: Bulletin of the Australian Mathematical Society, ISSN 0004-9727, E-ISSN 1755-1633, Vol. 68, nr 3, s. 481-490Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper we prove a new refinement of the weighted arithmetic-geometric mean inequality and apply this result in obtaining a sharpened version of the weighted Carleman's inequality

  • 75. Cizmesija, Alexandra
    et al.
    Persson, Lars-ErikLuleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Mathematical inequalities and applications: proceedings of the conference in honour of professor Josip Pecaric, Trogir, Croatia, June 8-14, 20082009Samlingsverk (redaktörskap) (Övrigt vetenskapligt)
  • 76.
    Cizmesija, Alexandra
    et al.
    Department of Mathematics, University of Zagreb.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Wedestig, Anna
    Weighted integral inequalities for Hardy and geometric mean operators with kernals over cones in Rn2005Ingår i: Italian Journal of Pure and Applied Mathematics, ISSN 1126-8042, nr 18, s. 89-118Artikel i tidskrift (Refereegranskat)
  • 77.
    Cobos, Fernando
    et al.
    Departamento de Análisis Matémático, Facultad de Matemáticas, Universidad Complutense de Madrid.
    Peetre, Jaak
    Matematiska institutionen, Lunds universitet.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    On the connection between real and complex interpolation of quasi-banach spaces1998Ingår i: Bulletin des Sciences Mathématiques, ISSN 0007-4497, E-ISSN 1952-4773, Vol. 122, nr 1, s. 17-37Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We describe a new approach to interpolate by the complex method quasi-Banach couples formed by real-intermediate spaces. End-point cases are also considered, and applications are given to function spaces and to operator spaces.

  • 78.
    Cobos, Fernando
    et al.
    Department of Mathematical Analysis, Faculty of Mathematics, Universidad Complutense de Madrid.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Real interpolation of compact operators between quasi-Banach spaces1998Ingår i: Mathematica Scandinavica, ISSN 0025-5521, E-ISSN 1903-1807, Vol. 82, nr 1, s. 138-160Artikel i tidskrift (Refereegranskat)
  • 79.
    Culjak, Vera
    et al.
    Department of Mathematics, Faculty of Civil Engineering, University of Zagreb.
    Pecaric, Josip
    Faculty of Textile Technology, University of Zagreb.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    A generalized Simpson, Trapetsoid and Ostrowski type inequality for convex functions2005Ingår i: Soochow Journal of Mathematics, ISSN 0250-3255, Vol. 31, nr 4, s. 617-627Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, the authors prove a new generalization and unification of some recent generalizations of Simpson, trapezoid and Ostrowski type inequalities for convex functions. Both the case with the usual canonical partition and the case with the generalized partition are considered

  • 80.
    Culjak, Vera
    et al.
    Department of Mathematics, Faculty of Civil Engineering, University of Zagreb.
    Pecaric, Josip
    Faculty of Textile Technology, University of Zagreb.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    A note on Simpson type numerical integration2003Ingår i: Soochow Journal of Mathematics, ISSN 0250-3255, Vol. 29, nr 2, s. 191-200Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Some new results concerning Simpson type numerical integration are proved, discussed and compared with other similar results in the literature. A technique to improve the error estimates also in some other recent related results is pointed out

  • 81.
    Cwikel, Michael
    et al.
    Department of Mathematics, Technion - Israel Institute of Technology.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Rochberg, Richard
    Washington University, St. Louis.
    Sparr, Gunnar
    Lund Institute of Technology.
    Jaak Peetre, the man and his work2002Ingår i: Function spaces, interpolation theory and related topics: proceedings of the International Conference in Honour of Jaak Peetre on His 65th Birthday, Lund, Sweden, August, 17 - 22, 2000 / [ed] Michael Cwikel, Berlin: Walter de Gruyter, 2002, s. 1-22Konferensbidrag (Refereegranskat)
  • 82. Dasht, Johan
    et al.
    Engström, Jonas
    Kufner, Alois
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Rothe's method for parabolic equations on non-cylindrical domains2006Ingår i: Advances in Algebra and Analysis, ISSN 0973-2306, Vol. 1, nr 1, s. 59-80Artikel i tidskrift (Refereegranskat)
  • 83. Dasht, Johan
    et al.
    Engström, Jonas
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Degeneracy in stochastic homogenization2003Ingår i: Proceedings of the International Conference on Composites Engineering: ICCE/10 / [ed] David Hui, 2003Konferensbidrag (Refereegranskat)
  • 84.
    Dechevski, Ljubomir T.
    et al.
    Department of Numerical Methods and Analysis, Technical University, Sofia.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Sharp generalized Carleman inequalities with minimal information about the spectrum1994Ingår i: Mathematische Nachrichten, ISSN 0025-584X, E-ISSN 1522-2616, Vol. 168, s. 61-77Artikel i tidskrift (Refereegranskat)
  • 85.
    Dechevsky, Ljubomir T.
    et al.
    Department of Numerical Methods and Analysis, Technical University, Sofia.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    On sharpness, applications and generalizations of some Carleman type inequalities1996Ingår i: Tohoku mathematical journal, ISSN 0040-8735, Vol. 48, nr 1, s. 1-22Artikel i tidskrift (Refereegranskat)
  • 86.
    Dechevsky, Lubomir T.
    et al.
    Narvik University College, 8505 Narvik, Norway.
    Grip, Niklas
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Sharp error estimates for approximation by wavelet frames in Lebesgue spaces2003Ingår i: Journal of Analysis and Applications, ISSN 0972-5954, Vol. 1, nr 1, s. 11-31Artikel i tidskrift (Refereegranskat)
  • 87.
    Dragomir, S. S.
    et al.
    Department of Mathematics, University of Timisoara.
    Pecaric, Josip
    Faculty of Textile Technology, University of Zagreb.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Some inequalities of Hadamard type1995Ingår i: Soochow Journal of Mathematics, ISSN 0250-3255, Vol. 21, nr 3, s. 335-341Artikel i tidskrift (Refereegranskat)
  • 88.
    Dragomir, S.S.
    et al.
    Department of Mathematics, University of Timisoara.
    Pecaric, J.
    Faculty of Textile Technology, University of Zagreb.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Properties of some functionals related to Jensen's inequality1995Ingår i: Acta Mathematica Hungarica, ISSN 0236-5294, E-ISSN 1588-2632, Vol. 69, nr 4, s. 129-143Artikel i tidskrift (Refereegranskat)
  • 89.
    Dunkels, Andrejs
    et al.
    Luleå tekniska universitet.
    Ekblom, Håkan
    Hedberg, Torbjörn
    Luleå tekniska universitet.
    Näslund, Reinhold
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Flervariabelanalys med numeriska metoder för tekniska högskolor1987Bok (Övrig (populärvetenskap, debatt, mm))
  • 90.
    Dunkels, Andrejs
    et al.
    Luleå tekniska universitet.
    Ekblom, Håkan
    Hednerg, Torbjörn
    Luleå tekniska universitet.
    Näslund, Reinhold
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Flervariabelanalys med numeriska metoder1990Bok (Övrig (populärvetenskap, debatt, mm))
  • 91.
    Dunkels, Andrejs
    et al.
    Luleå tekniska universitet.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Creative Teaching by Mistakes1980Ingår i: The College Mathematics Journal, ISSN 0746-8342, E-ISSN 1931-1346, Vol. 11, nr 5, s. 296-300Artikel i tidskrift (Refereegranskat)
  • 92.
    Englis, Miroslav
    et al.
    MÚ AV ČR, Zitná 25, 11567 Prague.
    Lukkassen, Dag
    Peetr, Jaak
    Centre for Mathematical Sciences, Lund University.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    On the formula of Jacques-Louis Lions for reproducing kernels of harmonic and other functions2004Ingår i: Journal für die Reine und Angewandte Mathematik, ISSN 0075-4102, E-ISSN 1435-5345, Vol. 570, s. 89-129Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In an earlier work, J.-L. Lions produced a means for creating reproducing formulas for the space of harmonic functions with Sobolev boundary values on a domain in real Euclidean space. The present authors give a new proof of this result and also generalize the Lions formula to handle spaces of functions that are annihilated by an elliptic operator. The method of constructing the reproducing kernels seems to be based on the old paradigm of Aronszajn and Bergman. It is interesting to note that this model---that the kernel should take the form $$ K(x,y)=\sum_j e_j(x)·e_j(y) $$ for a suitable orthonormal basis $\{e_j\}$---goes back to the thesis of Bochner. That thesis well predates the early work of Bergman and Szegö.

  • 93. Engström, Jonas
    et al.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Piatnitski, Andrey
    Narvik University College, 8505 Narvik, Norway.
    Wall, Peter
    Homogenization of random degenerated nonlinear monotone operators2006Ingår i: Glasnik Matematicki - Serija III, ISSN 0017-095X, E-ISSN 1846-7989, Vol. 41, nr 1, s. 101-114Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper deals with homogenization of random nonlinear monotone operators in divergence form. We assume that the structure conditions (strict monotonicity and continuity conditions) degenerate and are given in terms of a weight function. Under proper integrability assumptions on the weight function we construct the effective operator and prove the homogenization result.

  • 94. Ericsson, Stefan
    et al.
    Grip, Niklas
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Johansson, Elin
    Luleå tekniska universitet.
    Persson, Lars-Erik
    Sjöberg, Ronny
    Nåiden Teknik AB.
    Strömberg, Jan-Olov
    Department of Mathematics/NADA, Royal Institute of Technology.
    Towards automatic detection of local bearing defects in rotating machines2005Ingår i: Mechanical systems and signal processing, ISSN 0888-3270, E-ISSN 1096-1216, Vol. 19, nr 3, s. 509-535Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper we derive and compare several different vibration analysis techniques for automatic detection of local defects in bearings. Based on a signal model and a discussion on to what extent a good bearing monitoring method should trust it, we present several analysis tools for bearing condition monitoring and conclude that wavelets are especially well suited for this task. Then we describe a large-scale evaluation of several different automatic bearing monitoring methods using 103 laboratory and industrial environment test signals for which the true condition of the bearing is known from visual inspection. We describe the four best performing methods in detail (two wavelet-based, and two based on envelope and periodisation techniques). In our basic implementation, without using historical data or adapting the methods to (roughly) known machine or signal parameters, the four best methods had 9–13% error rate and are all good candidates for further fine-tuning and optimisation. Especially for the wavelet-based methods, there are several potentially performance improving additions, which we finally summarise into a guiding list of suggestion.

  • 95. Essel, Emmanuel Kwame
    et al.
    Kuliev, Komil
    Department of Mathematics and Statistics, University of Cape Coast.
    Kulieva, Gulchehra
    Department of Mathematics and Statistics, University of Cape Coast.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Homogenization of quasilinear parabolic problems by the method of rothe and two scale convergence2008Rapport (Övrigt vetenskapligt)
  • 96. Essel, Emmanuel Kwame
    et al.
    Kuliev, Komil
    Kuliev, Gulchehra
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    On linear parabolic problems with singular coefficients in non-cylindrical domains2006Rapport (Övrigt vetenskapligt)
  • 97. Essel, Emmanuel Kwame
    et al.
    Kuliev, Komil
    Department of Mathematics and Statistics, University of Cape Coast.
    Kulieva, Gulchehra
    Department of Mathematics and Statistics, University of Cape Coast.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Homogenization of quasilinear parabolic problems by the method of Rothe and two scale convergence2010Ingår i: Applications of Mathematics, ISSN 0862-7940, E-ISSN 1572-9109, Vol. 55, nr 4, s. 305-327Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We consider a quasilinear parabolic problem with time dependent coefficients oscillating rapidly in the space variable. The existence and uniqueness results are proved by using Rothe's method combined with the technique of two-scale convergence. Moreover, we derive a concrete homogenization algorithm for giving a unique and computable approximation of the solution.

  • 98. Euler, Norbert
    et al.
    Lindblom, Ove
    Luleå tekniska universitet.
    Euler, Marianna
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    The higher dimensional Bateman equation and Pailevé analysis of nonintegrable wave equations1997Ingår i: Proceedings of the second international conference: Memorial Prof. W. Fushchych conference, July 7 - 13, 1997, Kyiv, Ukraine / [ed] Mykola Shkil, Kyev: Institute of Mathematics of the National Academy of Sciences of Ukraine , 1997, Vol. 1, s. 185-192Konferensbidrag (Refereegranskat)
    Abstract [en]

    The paper starts with recalling the basics of the Painlevé analysis and its applications to the construction of particular solutions to nonintegrable equations. Next, the authors recall known facts on the Bateman equation in the space of $n$ independent variables and establish some properties of its solutions. It is further shown that the singular manifold equations, arising in the process of singularity analysis of the $n$-dimensional ($n\geq 2$ for double sine-Gordon and $n\geq 3$ for other equations) versions of Liouville, Tzitzéika-Mikhailov, sine-Gordon and double sine-Gordon equations, are equivalent to the Bateman equation. It is also proved that the general solution of the 2-dimensional Bateman equation satisfies the singular manifold equations for the equations $\partial^{2}u/\partial x\partial t+u^{k}=0$, $k\geq 2$.

  • 99.
    Finol, Carlos E.
    et al.
    Department of Mathematics, Central University of Venezuela.
    Maligranda, Lech
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Reiteration for and exact relations between some real interpolation spaces1991Ingår i: Function spaces: Proceedings of the 2nd international conference, Poznan, Poland, August 28-September 2, 1989 / [ed] Julian Musielak; Henry Hudzik; Ryszard Urbanski, Stuttgart: Teubner , 1991, s. 238-247Konferensbidrag (Refereegranskat)
  • 100. Gogatishvili, A.
    et al.
    Persson, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    Stepanov, V. D.
    Wall, Peter
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Matematiska vetenskaper.
    On scales of equivalent conditions characterizing weighted Stieltjes inequality2012Ingår i: Doklady Akademii Nauk, ISSN 0869-5652, Vol. 447, nr 1, s. 13-14Artikel i tidskrift (Refereegranskat)
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