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1.
F. Brock V. Ferone B. Kawohl 《Calculus of Variations and Partial Differential Equations》1996,4(6):593-599
Let be a ball in N, centered at zero, and letu be a minimizer of the nonconvex functional
over one of the classesC
M
:= {w W
loc
1,
() 0 w(x) M in,w concave} orE
M
:= {w W
loc
1,2
() 0 w(x) M in,w
0 inL()}of admissible functions. Thenu is not radial and not unique. Therefore one can further reduce the resistance of Newton's rotational body of minimal resistance through symmetry breaking. 相似文献
2.
M. Milman 《Analysis Mathematica》1978,4(3):215-223
X(Y) f -:X(Y)={fM(×): fX(Y)=f(x,.)YX< . =(0, ), M (×) — , ×, X, Y, Z— . X(Y) Z(×). 相似文献
3.
R. Ž. Nurpeisov 《Analysis Mathematica》1989,15(2):127-143
H
(G), f(g)H
(G) , (, 1)- OHMC G. , OHMC, A. H. . , . , OHMC, lim supp
n=, , ,n .. . , 117 234 . . - 相似文献
4.
F. Schipp 《Analysis Mathematica》1990,16(2):135-141
H={h
1,I } — , . : , I ¦(I)¦=¦I¦, ¦I¦ — I. H H
={h
(I),I} . , , . L
p
.
Dedicated to Professor B. Szökefalvi-Nagy on his 75th birthday
This research was supported in part by MTA-NSF Grants INT-8400708 and 8620153. 相似文献
Dedicated to Professor B. Szökefalvi-Nagy on his 75th birthday
This research was supported in part by MTA-NSF Grants INT-8400708 and 8620153. 相似文献
5.
Converse theorems for multidimensional Kantorovich operators 总被引:4,自引:0,他引:4
Ding -Xuan Zhou 《Analysis Mathematica》1993,19(1):85-100
L
p
[0, l]. . . - .
Supported by National Science Foundation, Zhejiang Provincial Science Foundation of China, and Alexander von Humboldt Foundation of Germany. 相似文献
Supported by National Science Foundation, Zhejiang Provincial Science Foundation of China, and Alexander von Humboldt Foundation of Germany. 相似文献
6.
Maxime Gouleau 《Annals of Global Analysis and Geometry》1987,5(3):217-259
Soient G une alébre de Lie nilpotente stratifée de rang 2, une sous-algébre de G, 0, la représentation de G dans l'espace L
2( \ G) indiute par le caractére trivial C, P un opérateur homogène appartenant à l'algébre universelle enveloppante (complexifiée) U(G) tel que l'opérateur 0, (P) soit hypoelliptique maximal. Cet opérateur peut s'exprimer par une intégrale dépendant de la restriction du symbole p de P au sousensemble = G · décrit par les orbites des éléments de dans la représentation contragrédiente de G dans G
*.Une algèbre de symboles définis sur est construite et permet de déterminer une paramétrixe de 0, (P); des résultats de réguralité de cet opérateur dans des espaces de Sobolev adaptés sont ensuite obtenus. 相似文献
7.
А. В. Резцов 《Analysis Mathematica》1995,21(2):129-135
Q (.. , L). Q . P(Sr(2)) — 2 (S
r(2) (r — ). , M(P(S
r(m=sup{t(·)t(·)1:t P(S
r(2)),t 0}. , /4+(1)M(P(S
r(2)))/r
215/17+(1)(r+). (Q), Q L. 相似文献
8.
Luigi Antonio Rosati 《Geometriae Dedicata》1987,24(3):261-267
Summary Let G be a sharply 3-transitive permutation set on a finite set E of even cardinality and let 1 be in G. The following theorems are proved.
G is one of the known examples if and only if there exists a non-identity normal subgroup N of G and an element of E such that NG
G.G is a group if and only if G for every G and for every G and for every G
.By using the classification of finite single groups a result concerning sharply k-transitive permutation sets k>3 is also proved.
Dedicato a Guido Zappa in occasione del suo 70° compleanno
Lavoro eseguito nell'ambito dei progetti finanziati dal Ministero della Pubblica Istruzione. 相似文献
Dedicato a Guido Zappa in occasione del suo 70° compleanno
Lavoro eseguito nell'ambito dei progetti finanziati dal Ministero della Pubblica Istruzione. 相似文献
9.
S. K. Sobolev 《Mathematical Notes》1977,22(1):528-532
Let L be the language of the intuitionistic propositional calculus J completed by the quantifiers and , and let calculus 2J in language L contain, besides the axioms of J, the axioms xB (x) B(y) and B(y) xB (x). A Kripke semantics is constructed for 2J and a completeness theorem is proven. A result of D. Gabbay is generalized concerning the undecidability of C2J+-extension of 2J by schemes x (x B) and x(A B(x))A xB (x) specificially: the undecidability is proven of each T theory in language L such that [2J]T [C2J+] ([2J] ([2J] denotes the set of all theorems of calculus 2J).Translated from Matematicheskie Zametki, Vol. 22, No. 1, pp. 69–76, July, 1977. 相似文献
10.
Rotraut Stanik 《Journal of Geometry》1992,43(1-2):188-197
Spaces called rectangular spaces were introduced in [5] as incidence spaces (P,G) whose set of linesG is equipped with an equivalence relation and whose set of point pairs P2 is equipped with a congruence relation , such that a number of compatibility conditions are satisfied. In this paper we consider isomorphisms, automorphisms, and motions on the rectangular spaces treated in [5]. By an isomorphism of two rectangular spaces (P,G, , ) and (P,G, , ) we mean a bijection of the point setP onto P which maps parallel lines onto parallel lines and congruent points onto congruent points. In the following, we consider only rectangular spaces of characteristic 2 or of dimension two. According to [5] these spaces can be embedded into euclidean spaces. In case (P,G, , ) is a finite dimensional rectangular space, then every congruence preserving bijection ofP onto P is in fact an isomorphism from (P,G, , ) onto (P,G, , ) (see (2.4)). We then concern ourselves with the extension of isomorphisms. Our most important result is the theorem which states that any isomorphism of two rectangular spaces can be uniquely extended to an isomorphism of the associated euclidean spaces (see (3.2)). As a consequence the automorphisms of a rectangular space (P,G, , ) are precisely the restrictions (onP) of the automorphisms of the associated euclidean space which fixP as a whole (see (3.3)). Finally we consider the motions of a rectangular space (P,G, , ). By a motion of(P.
G,, ) we mean a bijection ofP which maps lines onto lines, preserves parallelism and satisfies the condition((x), (y)) (x,y) for allx, y P. We show that every motion of a rectangular space can be extended to a motion of the associated euclidean space (see (4.2)). Thus the motions of a rectangular space (P,G, , ) are seen to be the restrictions of the motions of the associated euclidean space which mapP into itself (see (4.3)). This yields an explicit representation of the motions of any rectangular plane (see (4.4)).
Herrn Professor Burau zum 85. Geburtstag gewidmet 相似文献
Herrn Professor Burau zum 85. Geburtstag gewidmet 相似文献
11.
12.
Amos Nevo 《Geometriae Dedicata》2003,100(1):187-218
Let G denote a semisimple group, a discrete subgroup, B=G/P the Poisson boundary. Regarding invariants of discrete subgroups we prove, in particular, the following:(1) For any -quasi-invariant measure on B, and any probablity measure on , the norm of the operator () on L
2(B,) is equal to (), where is the unitary representation in L
2(X,), and is the regular representation of .(2) In particular this estimate holds when is Lebesgue measure on B, a Patterson–Sullivan measure, or a -stationary measure, and implies explicit lower bounds for the displacement and Margulis number of (w.r.t. a finite generating set), the dimension of the conformal density, the -entropy of the measure, and Lyapunov exponents of .(3) In particular, when G=PSL2() and is free, the new lower bound of the displacement is somewhat smaller than the Culler–Shalen bound (which requires an additional assumption) and is greater than the standard ball-packing bound.We also prove that ()=G() for any amenable action of G and L
1(G), and conversely, give a spectral criterion for amenability of an action of G under certain natural dynamical conditions. In addition, we establish a uniform lower bound for the -entropy of any measure quasi-invariant under the action of a group with property T, and use this fact to construct an interesting class of actions of such groups, related to 'virtual' maximal parabolic subgroups. Most of the results hold in fact in greater generality, and apply for instance when G is any semi-simple algebraic group, or when is any word-hyperbolic group, acting on their Poisson boundary, for example. 相似文献
13.
Summary We describe a large class of one-parameter families , {}, , of two-dimensional diffeomorphisms which arestable for <0, exhibit acycle for =0, and thereafter have a bifurcation set of positive but arbitrarily smallrelative measure for in small intervals [0, ]. A main assumption is that the basic sets involved in the cycle havelimit capacities that are not too large.The second author acknowledges hospitality and financial support from IMPA/CNPq during the period this paper was prepared 相似文献
14.
We prove that on a closed, smooth, convex surface of revolution , whose poles are not flattening points, there exists only a countable set of parallels n. Each of these parallels cuts surface into two parts so that one of the parts,
, admits nontrivial, infinitesimal bendings in the process of which all the points of its boundary n are displaced on a preassigned, conic sleeve K that is coaxial with the surface. The sequence of such parallels n converges to parallel *, which has the following properties: 1) the tangent cone to surface along * is orthogonal to sleeve K; 2) surface
, cut off from surface by parallel *, has rigidity of first order in the indicated class of bendings.Translated from Ukrainskii Geometricheskii Sbornik, No. 33, pp. 3–8, 1990. 相似文献
15.
S. V. Petras 《Journal of Mathematical Sciences》1984,24(3):380-386
The behavior of the poles zn(), n=1,2,... of the scattering matrix of the operatorl
u=–u(x), x , (u/n)+(x)u|=0 as 0 is considered. It is proved that |zn()–zn|=0((1/2)qn), where qn is the order of the pole of the scattering matrix for the operator 0u=–u, u/=0.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 117, pp. 183–191, 1981. 相似文献
16.
Xiang-Dong Hou 《Designs, Codes and Cryptography》1992,2(3):215-224
Let R(r, m) be the rth order Reed-Muller code of length 2
m
, and let (r, m) be its covering radius. We prove that if 2 k m - r - 1, then (r + k, m + k) (r, m + 2(k - 1). We also prove that if m - r 4, 2 k m - r - 1, and R(r, m) has a coset with minimal weight (r, m) which does not contain any vector of weight (r, m) + 2, then (r + k, m + k) (r, m) + 2k(. These inequalities improve repeated use of the known result (r + 1, m + 1) (r, m).This work was supported by a grant from the Research Council of Wright State University. 相似文献
17.
Wenpeng Zhang 《Acta Mathematica Hungarica》1998,78(4):345-357
Let p be an odd prime. For each integer a with x < a x + u and (a,p) = 1, we define by a 1 (mod p) and 1 p - 1. Let r(p,u,x) be the number of integers with x < a x + u and (a,p) = 1 for which a and are of opposite parity, and let E(n,u,x) = r(n,u,x) - 1/2
1, where
denotes summation over all a such that (a,p) = 1. The main purpose of this paper is to prove that for any positive integer 1 u
we have the asymptotic formula
. 相似文献
18.
Cai Tianxin 《数学学报(英文版)》1995,11(1):68-73
LetB
(a) be an additive function on a ring of integers in the quadratic number fieldQ(d) given byB
(a) =
p|a
*N
(p) with a fixed > 0, where the asterisk means that the summation is over the non-associate prime divisorsp of an integera inQ(d), N(a) is the norm ofa. In this paper we obtain the asymptotic formula of
N(a)x
*B
(a) in the case where the class-number ofQ(d) is one.Project supported by the National Natural Science Foundation of China. 相似文献
19.
Beitrag zur Reduktion des Entscheidungsproblems auf Klassen von Hornformeln mit kurzen Alternationen
Egon Börger 《Archive for Mathematical Logic》1974,16(1-2):67-84
Ohne Zusammenfassung
Zusatz bei der Korrektur: Ein vollständiger und korrekter Beweis für die Entscheidbarkeit der eingangs angeführten Aanderaaschen Klasse ((0, ), (, , ...)) erscheint demnächst im JSL (S.O. Aanderaa/H.R.Lewis: Prefix classes of Krom formulas). Ebendort wird auch die Reduktionstypeneigenschaft für ((0, ), (0, 0, )) und ((0, )), (0, 0, )) nachgewiesen, während ((0, ), (, )) sich als entscheidbar herausgestellt hat (s. E. Börger: Eine entscheidbare Klasse von Kromformeln. ZMLG 19 (1973), 117–120.) Der Kromsche Reduktionstyp konnte mittlerweile einerseits zu ((0, ), (0, 4)) verschärft werden (s. D. Rödding, E. Börger: The undecidability of (0, 4)-formulae with binary disjunctions, vorgetragen auf dem Logic Coll. Bristol 1973, ein abstract erscheint im JSL), andererseits kündigt H.R.Lewis die Reduktionstypeneigenschaft für ((0, ), (0, 1)) an (s. H.R.Lewis: Krom formulas with one dyadic predicate letter. Notices AMS 20, 5 (1973) A-500, abstr. no. 73T-E78.)Dieser Aufsatz geht aus der Dissertation [2] hervor, die dem Fachbereich Mathematik der Mathematisch-Naturwissenschaftlichen Fakultät der Universität Münster im Sommersemester 1971 vorgelegt worden ist. Die Ergebnisse stammen aus dem Wintersemester 1970/71. Eine Ankündigung der hauptsächlichen Resultate ist in den Notices of the American Mathematical Society 19, 2 (1972) A-333 unter der abstract no. * 72T-E24 erschienen. 相似文献
20.
Wojciech Jaworski 《Probability Theory and Related Fields》1995,101(2):147-171
Summary Consider a random walk of law on a locally compact second countable groupG. Let the starting measure be equivalent to the Haar measure and denote byQ the corresponding Markov measure on the space of pathsG
. We study the relation between the spacesL
(G
,
a
,Q) andL
(G
,
i
,Q) where
a
and
i
stand for the asymptotic and invariant -algebras, respectively. We obtain a factorizationL
(G
,
a
,Q) L
(G
,
i
,Q)L
(C) whereC is a cyclic group whose order (finite or infinite) coincides with the period of the Markov shift and is determined by the asymptotic behaviour of the convolution powers
n. 相似文献