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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.
We argue for the existence of structures with the spectrum {x : xa} of degrees, where a is an arbitrary low degree. Also it is stated that there exist structures with the spectrum of degrees, {x : xa} ⋃ {x : xb}, 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.
 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 :Ex1,x0}, P(C)={x∈ℜ n :Cx1,x0}, α E (G)=max{1 T x subject to xP(E)}, and α C (G)= max{1 T x subject to xP(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.
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 : BC 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 : BC n . In our main result (Theorem 4.1) we end the researches dedicated to quasiconformal extensions of K-quasiregular and holomorphic mappings f : BC n to C n . We show that a C 1 quasiconformal map f : BC 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.
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/2ZH 1(M,Z/2ZZ/2Z. Received: 8 June 2000 / Revised version: 2 October 2000  相似文献   

7.
 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.
In Short     
《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.
 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:
where is the graph of realizations of d. Thus the two invariants a:=min(ω,d) and b:=max(ω,d) naturally arise. For a graphic degree sequence d=r n :=(r,r,…,r) where r is the vertex degree and n is the number of vertices, the exact values of a and b are found in all situations. Since the independence number, α(G)=ω(Gˉ), we obtain parallel results for the independence number of graphs. Received: October, 2001 Final version received: July 25, 2002 RID="*" ID="*" Work supported by The Thailand Research Fund, under the grant number BRG/09/2545  相似文献   

13.
We show that if a smooth projective 4-fold M contains an ample divisor A which is P 1-bundle π :AS over a smooth projective surface S, π is extended to a P 2-bundle π :SS, 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 :AuA ∈ | 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.
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 nC 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 ΩC 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−mC n at infinitely many points. If m = n − 1, we construct F as above such that C nF(M) is hyperbolic. In particular, for each m ≥ 1we construct proper holomorphic embeddings F:C mC m−1 such that the complement C m+1F(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.
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.
Let ? = ?F, R, ρ? be a system language. Given a class of ?-systems K and an ?-algebraic system A = ?SEN,?N,F??, i.e., a functor SEN: Sign → Set, with N a category of natural transformations on SEN, and F:F → N a surjective functor preserving all projections, define the collection K A of A-systems in K as the collection of all members of K of the form 𝔄 = ? SEN,?N,F?,R 𝔄 ?, for some set of relation systems R 𝔄 on SEN. Taking after work of Czelakowski and Elgueta in the context of the model theory of equality-free first-order logic, several relationships between closure properties of the class K, on the one hand, and local properties of K A and global properties connecting K A and K A, whenever there exists an ?-morphism ? F,α? : A → A′, on the other, are investigated. In the main result of the article, it is shown, roughly speaking, that K A is an algebraic closure system, for every ?-algebraic system A, provided that K is closed under subsystems and reduced products.  相似文献   

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