Hysteresis in discrete systems of possibly interacting elements with a double-well energy

Summary We study in this paper the hysteretic behavior of a discrete system constituted by a finite number of elements (snap-springs) whose energy has two parabolic wells. The guideline idea is that, in many circumstances, hysteresis can be due to the presence of relative minimizers of a potential (metastable states) in which the system might get locked during its quasistatic evolution. A careful investigation is thus carried out of the relative minimizers of the total energy of our system of snap-springs under imposed total displacement, and of the barriers separating them. This is done both in the case of noninteracting elements and in the case in which some interaction is present that gives rise in the energy to an extra coherence term of special form. The results allow discussion of various hysteretic phenomena, also in the presence of vibrational motion of the elements. This study of a simple but suggestive discrete system will hopefully prove itself of help in understanding the implications regarding hysteresis of certain continuum theories recently proposed to model phase transitions in the solid state, in which the energy density is assumed, as here, to be biparabolic, and in which the coherence energy term we adopt arises in a natural way when equilibria involving mixtures of kinematically noncoherent phases are considered. In these cases the optimal microstructures are known to be layered, and physically this gives a good basis to our discrete calculation.     

Maximal inequalities,convexity inequality,and their duality. II

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On convergence of function series

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On the angular derivative and univalence

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Continuation of functionals on ultradifferentiable function spaces

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This work is supported by N.B.H.M. grant No. 48/1/94-R&D-II.     

Limiting behavior of certain mixtures of distributions

U — [0, 1] Y — . X=[1–U ^1/v /Y], U Y.     

Rate of approximation by rectangular partial sums of double orthogonal series

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Dedicated to Professor K. Tandori on his seventieth birthday

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This research was supported in part by Grant # K41 100 of the Joint Fund of the Government of Ukraine and the International Science Foundation.     

Exact estimates for partially monotone approximation

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Lattice Polytopes Associated to Certain Demazure Modules of sl n + 1

Let w be an element of the Weyl group of sl _{n + 1}. We prove that for a certain class of elements w (which includes the longest element w₀ of the Weyl group), there exist a lattice polytope R ^l(w) , for each fundamental weight _i of sl _{n + 1}, such that for any dominant weight = _{i = 1} ⁿ a _{i i} , the number of lattice points in the Minkowski sum _w = _{i = 1} ⁿ a _{i i} ^w is equal to the dimension of the Demazure module E _w (). We also define a linear map A ^w : R ^l(w) P _Z R where P denotes the weight lattice, such that char E _w () = e e^–A(x) where the sum runs through the lattice points x of ^w .     

The Dual of the martingale Hardy space ℋΦ with general Young function Φwith general Young function Φ

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О Сходимости метода подобластей

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Investigation of Haar and Franklin series in Hardy spaces

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Subsets with Restricted Movement

Let G be a finite permutation group on a set with no fixed points in and let m and k be integers with 0 < m < k. For a finite subset of the movement of is defined as move() = max_gG| ^g \ |. Suppose further that G is not a 2-group and that p is the least odd prime dividing |G| and move() m for all k-element subsets of . Then either || k + m or k (7m – 5) / 2, || (9m – 3)/2. Moreover when || > k + m, then move() m for every subset of .     

Groups acting simply transitively on the vertices of a building of typeà 2, II: The casesq=2 andq=3

If (P, L) is a projective plane and is a triangle presentation compatible with a point-line correspondence :P L, then gives rise to a group and a thick building of typeà ₂ on the vertices of which acts simply transitively. We find all triangle presentations (up to natural equivalence) compatible with some point-line correspondence :P L, when (P, L) is the projective plane of orderq=2 orq=3. For some, but not all, of these , is isomorphic to the building associated withG=PGL(3,K) whereK is a local field with discrete valuation and residual field of orderq. We identify the for which this is the case, and in these cases, find embeddings of intoG. We also describe the arithmetic nature of these groups.     

The trace to subsets ofR n of Besov spaces in the general case

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This work has been supported in part by the Swedish Natural Science Research Council.     

Convergence of simultaneous Padé approximants to two dilogarithms

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О лагранжевом интерполировании с узлами в корнях многочленов сонина-маркова

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On depth first search strees inm-out digraphs

We consider depth first search (DFS for short) trees in a class of random digraphs: am-out model. Let _i be thei ^th vertex encountered by DFS andL(i, m, n) be the height of _i in the corresponding DFS tree. We show that ifi/n asn, then there exists a constanta(,m), to be defined later, such thatL(i, m, n)/n converges in probability toa(,m) asn. We also obtain results concerning the number of vertices and the number of leaves in a DFS tree.     

On convex multipliers of convergence of some classes of bivariate fourier series

- ()N²,L _F ( ) — , 2- , {s _m() f} -L. — . (L _F( ),L _F( ) ={(k)} (kZ²) , fL_F( ) f , , L _F( ). - ={()} ={()} , n(())m()n(()+()) . R() , .. - . , . (L _F ( ),L _F ( )) , R(,)=O(1) (x).

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The author wishes to express his gratitude to S. A.Teljakovski for setting the problem and for his attention to this paper.     

Morera type theorems on the unit disc

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