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1.
《Change》2012,44(5):62-66
Abstract Everything Looks Impressive by Hugh Kennedy. New York: Doubteday, 1993, $10.00. Generation X: Tales For An Accelerated Culture by Douglas Coupland. New York: St. Martin's Press, 1991, $13.95. Also Cited: Campus Life: Undergraduate Cultures From The End Of The Eighteenth Century To The Present by Helen Lefkowitz Horowitz. New York: Alfred A. Knopf, 1987. Coming Of Age In New Jersey: College In American Culture by Michael Moffatt. New Brunswick: Rutgers University Press, 1989. Stover At Yale by Owen Johnson. New York: Collier Books, 1968 (originally published by Frederick A. Stokes Company, 1912). The Plastic Age by Percy Marks. New York: Grosset &; Dunlap, 1924. 相似文献
2.
I. Sh. Kalimullin 《Algebra and Logic》2007,46(6):399-408
We argue for the existence of structures with the spectrum {x : x ≰ a} of degrees, where a is an arbitrary low degree. Also it is stated that there exist structures with the spectrum of degrees, {x : x ≰ a} ⋃ {x : x ≰ b}, for any low degrees a and b.
Supported by RFBR grant No. 05-01-00605.
__________
Translated from Algebra i Logika, Vol. 46, No. 6, pp. 729–744, November–December, 2007. 相似文献
3.
Raffaele Mosca 《Graphs and Combinatorics》2001,17(3):517-528
Let G be a graph with n vertices, and denote as γ(G) (as θ(G)) the cardinality of a minimum edge cover (of a minimum clique cover) of G. Let E (let C) be the edge-vertex (the clique-vertex) incidence matrix of G; write then P(E)={x∈ℜ
n
:Ex≤1,x≥0}, P(C)={x∈ℜ
n
:Cx≤1,x≥0}, α
E
(G)=max{1
T
x subject to x∈P(E)}, and α
C
(G)= max{1
T
x subject to x∈P(C)}. In this paper we prove that if α
E
(G)=α
C
(G), then γ(G)=θ(G).
Received: May 20, 1998?Final version received: April 12, 1999 相似文献
4.
Mihai Cristea 《Complex Analysis and Operator Theory》2011,5(3):863-880
The paper continues the work of Royster (Duke Math J 19:447–457, 1952), Mocanu [Mathematica (Cluj) 22(1):77–83, 1980; Mathematica
(Cluj) 29:49–55, 1987], Cristea [Mathematica (Cluj) 36(2):137–144, 1994; Complex Var 42:333–345, 2000; Mathematica (Cluj)
43(1):23–34, 2001; Mathematica (Cluj), 2010, to appear; Teoria Topologica a Functiilor Analitice, Editura Universitatii Bucuresti,
Romania, 1999] of extending univalence criteria for complex mappings to C
1 mappings. We improve now the method of Loewner chains which is usually used in complex univalence theory for proving univalence
criteria or for proving quasiconformal extensions of holomorphic mappings f : B → C
n
to C
n
. The results are surprisingly strong. We show that the usual results from the theory, like Becker’s univalence criteria remain
true for C
1 mappings and since we use a stronger form of Loewner’s theory, we obtain results which are stronger even for holomorphic
mappings f : B → C
n
. In our main result (Theorem 4.1) we end the researches dedicated to quasiconformal extensions of K-quasiregular and holomorphic mappings f : B → C
n
to C
n
. We show that a C
1 quasiconformal map f : B → C
n
can be extended to a quasiconformal map F : C
n
→ C
n
, without any metric condition imposed to the map f. 相似文献
5.
6.
Rosa Gini 《manuscripta mathematica》2001,104(1):49-69
Some properties of non-orientable 3-manifolds are shown. In particular, for a connected, non-orientable 3-manifold M, the group of cobordism clases of immersions of surfaces in M is isomorphic to a group structure on the set H
2(M,Z/2Z)×H
1(M,Z/2Z)×Z/2Z.
Received: 8 June 2000 / Revised version: 2 October 2000 相似文献
7.
Narong Punnim 《Graphs and Combinatorics》2002,18(3):597-603
We prove that if G runs over the set of graphs with a fixed degree sequence d, then the values χ(G) of the function chromatic number completely cover a line segment [a,b] of positive integers. Thus for an arbitrary graphical sequence d, two invariants minχ(d):=a and maxχ(d):=b naturally arise. For a regular graphical sequence d=r
n
:=(r,r,…,r) where r is the degree and n is the number of vertices, the exact values of a and b are found in all situations, except the case where n and r are both even and n<2r.
Received: September 16, 2000 Final version received: December 13, 2001
Acknowledgments. We would like to thank Professor Tommy R. Jensen for his useful comment and editing thorough the paper. 相似文献
8.
Guangquan Guo 《代数通讯》2013,41(6):2269-2280
In this article, the notions of a Frobenius pair of functors and Frobenius corings are generalized to an l-QF pair of functors and l-QF corings. We prove that an extension ι:B → A is left quasi-Frobenius if and only if (F 1,G 1) is an l-QF pair of functors, where F 1: A ? → B ? is the restriction of scalars functors, and G 1 = A? B ? : B ? → A ? is the induction functor. For an A-coring , we prove that is an l-QF coring if and only if A → ? is an l-QF extension and A is a finitely generated projective modules if and only if (G 2,F 2) is an l-QF pair of functors, where G 2 = ? A ? : A ? → ? is the induction functor, F 2: ? → A ? is the forgetful functor, the result of Brzezinski is generalized. 相似文献
9.
J. B. Lasserre 《TOP》2012,20(1):119-129
We consider the semi-infinite optimization problem:
f*:=minx ? X {f(x):g(x,y) £ 0, "y ? Yx},f^*:=\min_{\mathbf{x}\in\mathbf{X}} \bigl\{f(\mathbf{x}):g(\mathbf{x},\mathbf{y}) \leq 0, \forall\mathbf{y}\in\mathbf {Y}_\mathbf{x}\bigr\}, 相似文献
10.
《Change》2012,44(5)
Abstract The Great Transformation in Higher Education, 1960–1980 by Clark Kerr, Albany; State University of New York Press, 1991, xxii + 383 pages, notes, index. Learning in Adulthood: A Comprehensive Guide by Sharon B. Merriam and Rosemary S. Caffarella, San Francisco, Oxford: Jossey-Bass, 1991, xx + 376 pages, references, indices. Literacy in the United States: Readers and Reading Since 1880 by Carl F. Kaestle, et al. New Haven, London: Yale University Press, 1991, xxiii + 338 pages, appendix, bibliography, index. Major American Higher Education Issues and Answers in the 1990s by Richard I. Miller, London: Jessica Kingsley, 1990, 219 pages, references, index. 相似文献
11.
Let Top
0
be the category of topological T
0-spaces, QU
0
the category of quasi-uniform T
0-spaces, T : QU
0
→ Top
0
the usual forgetful functor and K : QU
0
→ QU
0
the bicompletion reflector with unit k : 1 → K. Any T-section F : Top
0
→ QU
0
is called K-true if KF = FTKF, and upper (lower)
K-true if KF is finer (coarser) than FTKF. The literature considers important T-sections F that enjoy all three, or just one, or none of these properties. It is known that T(K,k)F is well-pointed if and only if F is upper K-true. We prove the surprising fact that T(K,k)F is the reflection to Fix(TkF) whenever it is idempotent. We also prove a new characterization of upper K-trueness. We construct examples to set apart some natural cases. In particular we present an upper K-true F for which T(K,k)F is not idempotent, and a K-true F for which the coarsest associated T-preserving coreflector in QU
0
is not stable under K.
We dedicate this paper to the memory of Sérgio de Ornelas Salbany (1941–2005). 相似文献
12.
Narong Punnim 《Graphs and Combinatorics》2002,18(4):781-785
Let ω(G) be the clique number of a graph G. We prove that if G runs over the set of graphs with a fixed degree sequence d, then the values ω(G) completely cover a line segment [a,b] of positive integers. For an arbitrary graphic degree sequence d, we define min(ω,d) and max(ω,d) as follows:
13.
We show that if a smooth projective 4-fold M contains an ample divisor A which is P
1-bundle π :A→S over a smooth projective surface S, π is extended to a P
2-bundle π :S→S, unless $A$ is isomorphic to P
2×P
1.
Received: 28 September 1998 / Revised version: 16 August 1999 相似文献
14.
A. W. Hager 《代数通讯》2013,41(5):1487-1503
Let frA denote the category of f-rings which are reduced and Archimedean, and let Φ be the (nonfull) subcategory of such rings with identity (each with the natural morphisms). Some time ago, the second author showed, using his representation theory, that for each A ∈ | frA| there is a certain minimal embedding u A :A→ uA ∈ | Φ|. More recently, he has revisited the representation theory, expanding it to include the representation of morphisms. Based upon this, the present article analyzes the operator u:| frA| → Φ: the construction of uA is tidied, several characterizations of the pair (u A , uA) are given, and the relation between the maximal ideal structures of A and uA is described. Membership in the class U of frA-morphisms that are “u-extendable” is characterized and it is shown that U = (| frA|,U) is a category in which Φ is a full essentially-reflective subcategory. The frA-objects are characterized for which, respectively, ? B(frA(A, B) = U (A, B)), and, ? B ≠ 0(frA(B, A) = U(B, A)). 相似文献
15.
Franc Forstneric 《Journal of Geometric Analysis》1999,9(1):93-117
Let n > 1 and let
C
n
denote the complex n-dimensional Euclidean space. We prove several jet-interpolation results for nowhere degenerate entire
mappings F:C
n →C
n
and for holomorphic automorphisms of
C
n
on discrete subsets of
C
n.We also prove an interpolation theorem for proper holomorphic embeddings of Stein manifolds into
C
n.For each closed complex submanifold (or subvariety) M ⊂
C
n
of complex dimension m < n we construct a domain Ω ⊂C
n
containing M and a biholomorphic map F: Ω →
C
n
onto
C
n
with J F ≡ 1such that F(M) intersects the image of any nondegenerate entire map G:C
n−m →C
n
at infinitely many points. If m = n − 1, we construct F as above such that
C
n ∖F(M) is hyperbolic. In particular, for each m ≥ 1we construct proper holomorphic embeddings F:C
m →C
m−1
such that the complement
C
m+1 ∖F(C
m
)is hyperbolic. 相似文献
16.
《代数通讯》2013,41(9):2899-2920
ABSTRACT Let R be a Noetherian ring and M a finitely generated R -module. In this article, we introduce the set of prime ideals Fnd M , the foundation primes of M . Using the fact that this set is nicely organized by foundation levels, we present an approach to the problem of understanding Annspec M , the annihilator primes of M , via Fnd M . We show: (1) Fnd M is a finite set containing Annspec M . Further, suppose that moreover every ideal of R has a centralizing sequence of generators; now, Annspec M is equal to the set Ass M of associated primes of M. Then: (2) For an arbitrary P ∈ Fnd M , P ∈ Annspec M if and only if there is no Q ∈ Annspec M such that P contains Q , and at the same time, the minimal foundation level on which appears P is greater than the minimal foundation level on which appears Q . 相似文献
17.
By a totally regular parallelism of the real projective 3-space
P3:=PG(3, \mathbb R){\Pi_3:={{\rm PG}}(3, \mathbb {R})} we mean a family T of regular spreads such that each line of Π
3 is contained in exactly one spread of T. For the investigation of totally regular parallelisms the authors mainly employ Klein’s correspondence λ of line geometry and the polarity π
5 associated with the Klein quadric H
5 (for details see Chaps. 1 and 3). The λ-image of a totally regular parallelism T is a hyperflock of H
5, i.e., a family H of elliptic subquadrics of H
5 such that each point of H
5 is on exactly one subquadric of H. Moreover, {p5(span l(X))|X ? T}=:HT{\{\pi_5({{\rm span}} \,\lambda(\mathcal {X}))\vert\mathcal {X}\in\bf{T}\}=:\mathcal {H}_{\bf{T}}} is a hyperflock determining line set, i.e., a set Z{\mathcal {Z}} of 0-secants of H
5 such that each tangential hyperplane of H
5 contains exactly one line of Z{\mathcal {Z}} . We say that dim(span HT)=:dT{{{\rm dim}}({{\rm span}}\,\mathcal {H}_{\bf{T}})=:d_{\bf{T}}} is the dimension of
T and that T is a d
T
- parallelism. Clifford parallelisms and 2-parallelisms coincide. The examples of non-Clifford parallelisms exhibited in Betten
and Riesinger [Result Math 47:226–241, 2004; Adv Geom 8:11–32, 2008; J Geom (to appear)] are totally regular and of dimension
3. If G{\mathcal{G}} is a hyperflock determining line set, then {l-1 (p5(X) ?H5) | X ? G}{\{\lambda^{-1}\,{\rm (}\pi_5(X){\,\cap H_5)\,|\, X\in\mathcal{G}\}}} is a totally regular parallelism. In the present paper the authors construct examples of topological (see Definition 1.1)
4- and 5-parallelisms via hyperflock determining line sets. 相似文献
18.
Jean B. Lasserre 《Optimization Letters》2011,5(4):549-556
We consider the convex optimization problem P:minx {f(x) : x ? K}{{\rm {\bf P}}:{\rm min}_{\rm {\bf x}} \{f({\rm {\bf x}})\,:\,{\rm {\bf x}}\in{\rm {\bf K}}\}} where f is convex continuously differentiable, and
K ì \mathbb Rn{{\rm {\bf K}}\subset{\mathbb R}^n} is a compact convex set with representation
{x ? \mathbb Rn : gj(x) 3 0, j = 1,?,m}{\{{\rm {\bf x}}\in{\mathbb R}^n\,:\,g_j({\rm {\bf x}})\geq0, j = 1,\ldots,m\}} for some continuously differentiable functions (g
j
). We discuss the case where the g
j
’s are not all concave (in contrast with convex programming where they all are). In particular, even if the g
j
are not concave, we consider the log-barrier function fm{\phi_\mu} with parameter μ, associated with P, usually defined for concave functions (g
j
). We then show that any limit point of any sequence (xm) ì K{({\rm {\bf x}}_\mu)\subset{\rm {\bf K}}} of stationary points of fm, m? 0{\phi_\mu, \mu \to 0} , is a Karush–Kuhn–Tucker point of problem P and a global minimizer of f on K. 相似文献
19.
Let s ∈ {2.3,…} and E be an Archimedean vector lattice. We prove that there exists a unique pair (E ? ,?), where E ? is an Archimedean vector lattice and ?:E× ··· ×E (s times) → E ? is a symmetric lattice s-morphism, such that for every Archimedean vector lattice F and every symmetric lattice s-morphism T:E × ··· × E (s times) → F, there exists a unique lattice homomorphism T ? :E ? → F such that T = T ? ○?. We give two approaches to construct (E ? ,?) based on f-algebras and functional calculus, respectively, provided that E is also uniformly complete. 相似文献
20.
George Voutsadakis 《代数通讯》2013,41(8):3093-3112
Let ? = ?F, R, ρ? be a system language. Given a class of ?-systems
|