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991.
Max Karoubi 《K-Theory》1990,4(1):55-87
Résumé Dans cet article nous définissons un nouveau foncteur MK(X), K-théorie multiplicative de X, dans lequel prennent leurs valeurs les classes caractéristiques primaires et secondaires connues de fibrés vectoriels munis de structures supplementaires. Il s'agit notamment des classes caractéristiques de fibrés plats, feuilletés ou holomorphes ainsi que des régulateurs en K-théorie algébrique.
In this paper we define a new functor MK(X), multiplicative K-theory of X, which is the target of known characteristic classes (primary and secondary) of vector bundles provided with additional structures. One should mention characteristic classes of flat, foliated or holomorphic vector bundles as well as regulators in algebraic K-theory.
A Alexander Grothendieck pour son 60e anniversaire 相似文献
992.
Bruno Kahn 《K-Theory》1991,5(6):555-566
Let F be a field, G
F its absolute Galois group, : G
FGL(C) a continuous complex representation of G
F and c
i() H2i(F, Z) its Chern classes. We show, under a mild assumption on F. that c
i ()=0 for all i2. For general F, one has that 2ci ()=0 for all i 2.
Cette dernière condition résulte en fait de la continuité de . 相似文献
993.
The central path plays a very important role in interior-point methods. By an equivalent reformulation of the central path, we obtain a new search direction which targets at a small neighborhood of the central path. For a full-Newton step interior-point algorithm based on this search direction, the complexity bound of the algorithm is the best known for linear optimization. 相似文献
994.
We classify all closed non-orientable -irreducible 3-manifolds with complexity up to 7, fixing two mistakes in our previous complexity-up-to-6 classification. We show that there is no such manifold with complexity less than 6, five with complexity 6 (the four flat ones and the filled Gieseking manifold, which is of type Sol), and three with complexity 7 (one manifold of type Sol, and the two manifolds of type with smallest base orbifolds). 相似文献
995.
Asymptotic Geometry and Growth of Conjugacy Classes of Nonpositively Curved Manifolds 总被引:1,自引:0,他引:1
Gabriele Link 《Annals of Global Analysis and Geometry》2007,31(1):37-57
Let X be a Hadamard manifold and Γ⊂Isom(X) a discrete group of isometries which contains an axial isometry without invariant flat half plane. We study the behavior
of conformal densities on the limit set of Γ in order to derive a new asymptotic estimate for the growth rate of closed geodesics
in not necessarily compact or finite volume manifolds.
Mathematics Subject Classifications (2000): 20E45, 53C22, 37F35 相似文献
996.
This note investigates two-machine flow shop scheduling with transportation constraints to minimize makespan. Recently, Soukhal et al. [A. Soukhal, A. Oulamara, P. Martineau, Complexity of flow shop scheduling problems with transportation constraints, European Journal of Operational Research 161 (2005) 32–41] proved that this problem is strongly NP-hard when the capacity of the truck is limited to two or three parts. The considered problem with blocking constraints is also proved to be strongly NP-hard by Soukhal et al. Unfortunately, their proofs contain mistakes. We point out their proofs’ invalidity and then show that, when the capacity of the truck is limited to two parts, the problem is binary NP-hard, and when the capacity of the truck is limited to three parts the problem is strongly NP-hard even if the jobs have a common processing time on machine one and all jobs have the same transportation time. We show also that the last result can be generalized to any fixed c (c ? 3) parts. 相似文献
997.
Consider a set of n fixed length intervals and a set of n (larger) windows, in one-to-one correspondence with the intervals, and assume that each interval can be placed in any position
within its window. If the position of each interval has been fixed, the intersection graph of such set of intervals is an
interval graph. By varying the position of each interval in all possible ways, we get a family of interval graphs. In the
paper we define some optimization problems related to the clique, stability, chromatic, clique cover numbers and cardinality
of the minimum dominating set of the interval graphs in the family, mainly focussing on complexity aspects, bounds and solution
algorithms. Some problems are proved to be NP-hard, others are solved in polynomial time on some particular classes of instances.
Many practical applications can be reduced to these kind of problems, suggesting the use of Shiftable Intervals as a new interesting
modeling framework. 相似文献
998.
999.
Renzo Cavalieri 《Advances in Mathematics》2008,218(5):1419-1429
We describe explicit generating functions for a large class of Hurwitz-Hodge integrals. These are integrals of tautological classes on moduli spaces of admissible covers, a (stackily) smooth compactification of the Hurwitz schemes.Admissible covers and their tautological classes are interesting mathematical objects on their own, but recently they have proved to be a useful tool for the study of the tautological ring of the moduli space of curves, and the orbifold Gromov-Witten theory of DM stacks. 相似文献
1000.
设P(G,λ)是图的色多项式。如果对任意使P(G,λ)=P(H,λ)的图H都与G同构,则称图G是色唯一图.这里通过比较t 1色类的色划分数目,讨论了由Koh和Teo在文献[1]中提出的问题(若|ni-nj|≤2,当min(n1,n2,…,nt)充分大时,完全t部图K(n1,n2,…,nt)是否是色唯一图?)。改进了文献[5]中的结果。证明了若Σ1≤i≤ta2i=T,min{n a1,n a2,…,nt at,n-1}≥(T 1)/2,则K(n a1,n a2,…,n at)是色唯一图(其中ai是实数,n ai是正整数)。从而证明了若|ni-nj|≤k(i,j=1,2,…,t),min{n1,n2,…,nt}≥tk2/8 1,则K(n1,n2,…,nt)是色唯一图。 相似文献