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1.
LetX be a reduced compact complex space, X a coherent sheaf, andV=V() its associated linear fiber space. LetV R be the reduction ofV, letA be the analytic set inX over which is not locally-free, and letV be the closure inV R ofV R |(X–A). is (primary) weakly positive if the zerosection ofV (V) is exceptional. is (primary) cohomologically positive if, for any coherent sheaf X, for all 0,k1. Then is (primary) weakly positive if and only if is (primary) cohomologically positive.LetX be a normal irreducible compact complex space. ThenX is Moishezon if and only if it carries a primary weakly positive, and hence primary cohomologically positive, coherent sheaf.Several other positivity notions are also discussed.  相似文献   

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f . , , — , A f f(). , , f() 0 . , , ,A , f . , f() - f() . , , . (1976) ( ¦f(z)¦<1) . . (1969) ( ).  相似文献   

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For a class of structural sets of penalty functions={i} i=1 n with lower quasiconvex functions i defined for sets of jobs={i} i=1 n , one gives an algorithm for solving the problem n /1/ preemp ¦ max, having order 0(np), where n is the number of jobs i and p is the total length of the completion of all jobs of the set.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 102, pp. 61–67, 1980.In conclusion, the author expresses her gratitude to K. V. Shakhbazyan for his interest in this paper.  相似文献   

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Analogues are formulated of the well-known, in the theory of analytic functions, Phragmen-Lindelöf theorem for the gradients of solutions of a broad class of quasilinear equations of elliptic type. Examples are given illustrating the accuracy of the results obtained for the gradients of solutions of the equations of the form div(|U|–2u)=f(x, u, u), where f(x, u, u) is a function locally bounded in 2n+1. f(x, 0, u)=0, uf(x, u, u) c¦u¦1+q(1+ ¦u|), > 1, c > 0, q > 0, is an arbitrary real number, and n >- 2. The basic role in the technique employed in the paper is played by the apparatus of capacitary characteristics.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 44, No. 10, pp. 1376–1381, October, 1992.The author sincerely appreciates E. M. Landis's permanent attention and numerous useful discussions.  相似文献   

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In this paper we continue the study of Tbk-semigroups [1]. We define a weak Tbk-semigroup as an algebra (s,·,) which satisfies (A1) a(bc) = (ab)c, (A2) (S, ) is a semilattice, (A3) × (a b) y = xay xby, (A4) a (a b) S S (a b) . We shall prove that every weak Tbk-semigroup can be embedded into a Tbk-semigroup with 1, and we shall show that the theory of [1] can be developed already in weak Tbk-semigroups.

Über den Inhalt dieser Note berichtete der Autor verschiedene Male , zuletzt im Juni 1974 an der T.U. München.  相似文献   

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Let G be a graph with order p, size q and component number . For each i between p – and q, let be the family of spanning i-edge subgraphs of G with exactly components. For an integer-valued graphical invariant if H H is an adjacent edge transformation (AET) implies |(H)-(H')|1 then is said to be continuous with respect to AET. Similarly define the continuity of with respect to simple edge transformation (SET). Let M j() and m j() be the invariants defined by . It is proved that both M p–() and m p–(;) interpolate over , if is continuous with respect to AET, and that M j() and m j() interpolate over , if is continuous with respect to SET. In this way a lot of known interpolation results, including a theorem due to Schuster etc., are generalized.  相似文献   

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This paper deals with linear systems of difference equations whose coefficients admit generalized factorial series representations atz=. We are concerned with the behavior of solutions near the pointz= (the only fixed singularity for difference equations). It is important to know whether a system of linear difference equations has a regular singularity or an irregular singularity. To a given system () we can assign a number , called the Moser's invariant of (), so that the system is regular singular if and only if 1. We shall develop an algorithm, implementable in a computer algebra system, which reduces in a finite number of steps the system of difference equations to an irreducible form. The computation ot the number can be done explicitly from this irreducible form.  相似文献   

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Summary Forf ( C n() and 0 t x letJ n (f, t, x) = (–1)n f(–x)f (n)(t) +f(x)f (n) (–t). We prove that the only real-analytic functions satisfyingJ n (f, t, x) 0 for alln = 0, 1, 2, are the exponential functionsf(x) = c e x,c, . Further we present a nontrivial class of real-analytic functions satisfying the inequalitiesJ 0 (f, x, x) 0 and 0 x (x – t)n – 1Jn(f, t, x)dt 0 (n 1).  相似文献   

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Tamás Szamuely 《K-Theory》1999,18(2):173-179
For a proper smooth variety X defined over a local field k, unramified class field theory investigates the reciprocity map X: SK1(X) ab 1(X) as introduced by S. Saito. We study this map in the case when X is a surface admitting a proper surjection onto a smooth geometrically connected curve C with a smooth conic as generic fibre. Without any assumption on the reduction of C, we prove that X is injective modulo n for all n invertible in k and its cokernel is the same as that of C.  相似文献   

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Let u be the solution of the equation u=f with a finite function f in the exterior domain Ru and satisfying the conditions u¦=0, u0 as ¦x¦ . It is shown that the coercive estimate is valid only for p < n/2. For p n/2 it holds for the solution of the exterior Dirichlet problem, which does not vanish at infinity, and may tend to constant or even to a linear (for p > n) function.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 146, pp. 92–101, 1985.  相似文献   

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A family of subtrees of a graphG whose edge sets form a partition of the edge set ofG is called atree decomposition ofG. The minimum number of trees in a tree decomposition ofG is called thetree number ofG and is denoted by(G). It is known that ifG is connected then(G) |G|/2. In this paper we show that ifG is connected and has girthg 5 then(G) |G|/g + 1. Surprisingly, the case wheng = 4 seems to be more difficult. We conjecture that in this case(G) |G|/4 + 1 and show a wide class of graphs that satisfy it. Also, some special graphs like complete bipartite graphs andn-dimensional cubes, for which we determine their tree numbers, satisfy it. In the general case we prove the weaker inequality(G) (|G| – 1)/3 + 1.  相似文献   

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Summary This paper is concerned with the rate of convergence to zero of theL pmetrics np1p, constructed out of differences between distribution functions, for departure from normality for normed sums of independent and identically distributed random variables with zero mean and unit variance. It is shown that the np are, under broad conditions, asymptotically equivalent in the strong sense that, for 1p, p, np/np is universally bounded away from zero and infinity asn.  相似文献   

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, ( ) . , : , , .

This research was partially supported by National Science Foundation under grant INT-8400708.  相似文献   

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H (G), f(g)H (G) , (, 1)- OHMC G. , OHMC, A. H. . , . , OHMC, lim supp n=, , ,n .. . , 117 234 . . -   相似文献   

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- L. , .

This paper is to be part of the author's doctoral dissertation written at the University of Campinas under the supervision of Prof. D. L. Fernandez.  相似文献   

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(L 1,H) (, ) , ; H — . , , L 1 . [13] , . , , , .  相似文献   

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