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971.
To every finite-dimensional irreducible representation V of the quantum group U(g) where is a primitive lth root of unity (l odd) and g is a finite-dimensional complex simple Lie algebra, de Concini, Kac and Procesi have associated a conjugacy class C
V
in the adjoint group G of g. We describe explicitly, when g is of type A
n
, B
n
, C
n
, or D
n
, the representations associated to the conjugacy classes of minimal positive dimension. We call such representations fundamental and prove that, for any conjugacy class, there is an associated representation which is contained in a tensor product of fundamental representations. 相似文献
972.
Lu Zhi-Cheng 《Letters in Mathematical Physics》1992,25(1):51-59
It is shown for a family of *-products (i.e. different ordering rules) that, under a strong invariance condition, the functions of the quadratic preferred observables (which generate the Cartan subalgebra in phase space realization of Lie algebras) take only the linear or exponential form. An exception occurs for the case of a symmetric ordering *-product where trigonometric functions and two special polynomials can also be included. As an example, the quantized algebra of the oscillator Lie algebra is argued. 相似文献
973.
974.
针对某型单脉冲测量雷达对A/ R 型显示终端提出的多路、高带宽、多目标、连续全量程视频实时显示,雷达工作日志录取及与指控中心数据交互的需求,设计了一种基于嵌入式计算机和现场可编程门阵列的A 显处理模块,解决了高速视频传输、大带宽数据实时处理、数据录取远程交互等技术问题,实现了显示终端的小型化,满足了雷达系统战术要求。工程实践表明:A 显处理模块实现了多输入多输出的雷达视频处理功能,提高了雷达A 显实时显示分析及雷达目标人工辅助辨性的能力。 相似文献
975.
Xiaotie Deng 《Combinatorica》1996,16(4):453-464
In this paper, we consider the following distributed bipartite matching problem: LetG=(L,R;E) be a bipartite graph in which boys are partL (left nodes), and girls are partR (right nodes.) There is an edge(l
i
,r
j
)E iff boyl
i
is interested in girlr
j
. Every boyl
i
will propose to a girlr
j
among all those he is interested in, i.e., his adjacent right nodes in the bipartite graphG. If several boys propose to the same girl, only one of them will be accepted by the girl. We assume that none of the boys communicate with others. This matching problem is typical of distributed computing under incomplete information: Each boy only knows his own preference but none of the others. We first study the one-round matching problem: each boy proposes to at most one girl, so that the total number of girls receiving a proposal is maximized. If the maximum matching isM, then no deterministic algorithm can produce a matching of size not bounded by a constant, but a randomized algorithm achieves
— and this is shown optimal by an adversary argument. If we allow many rounds in matching, with the senders learning from their failures, then, for deterministic algorithms, the ratio (of the optimal solution to the solution of the algorithm) is unbounded when the number of rounds is smaller than (G), and becomes bounded (two) at the (G)-th round. In contrast, an extension of the one-round randomized algorithm establishes that there is no such discontinuity in the randomized case. This randomized result is also matched by an upper bound of asymptotically the same order. 相似文献
976.
Salvatore A. Marano 《Set-Valued Analysis》1996,4(3):287-300
Let be a bounded domain in n (n3) having a smooth boundary, let be an essentially bounded real-valued function defined on × h, and let be a continuous real-valued function defined on a given subset Y of Y h. In this paper, the existence of strong solutions u W
2,p (, h) W
o
1,p
(n/2<p<+) to the implicit elliptic equation (–u)=(x,u), with u=(u1, u2, ..., uh) and u=(u
1, u
2, ..., u
h), is established. The abstract framework where the problem is placed is that of set-valued analysis. 相似文献
977.
The relation between the set of transformations
of the quantum plane and the quantum universal enveloping algebra U
q
(u(2)) is investigated by constructing representations of the factor algebra U
q
(u(2))*
. The noncommuting coordinates of
, on which U
q
(2) * U
q
(2) acts, are realized as q-spinors with respect to each U
q
(u(2)) algebra. The representation matrices of U
q
(2) are constructed as polynomials in these spinor components. This construction allows a derivation of the commutation relations of the noncommuting coordinates of
directly from properties of U
q
(u(2)). The generalization of these results to U
q
(u(n)) and
is also discussed. 相似文献
978.
Nobuaki Obata 《Monatshefte für Mathematik》1997,124(4):317-335
Let
be a barreled locally convex space. A continuous operator on
is called anequicontinuous generator if {
n
/n!;n=0,1,2,...} is an equicontinuous family of operators. For each equicontinuous generator a one-parameter group of operators is constructed by means of power series. There is a one-to-one correspondence between the equicontinuous generators and the locally equicontinuous holomorphic one-parameter groups of operators. If two equicontinuous generators 1, 2 satisfy [1,2]=2 for some thena1+b2 is also an equicontinuous generator for anya, b. These general results are applied to a study of operators on white noise functions. In particular, a linear combination of the number operator and the Gross Laplacian, which are natural infinite dimensional analogues of a finite dimensional Laplacian, is always an equicontinuous generator. This result contributes to the Cauchy problems in white noise (Gaussian) space.Work supported by Alexander von Humboldt-Stiftung and Japan Society for Promotion of Sciences 相似文献
979.
Singular integral equations with Cauchy kernel and piecewise-continuous matrix coefficients on open and closed smooth curves are replaced by integral equations with smooth kernels of the form(t–)[(t–)
2–n
2
(t)
2]–1,0, wheren(t), t , is a continuous field of unit vectors non-tangential to . we give necessary and sufficient conditions under which the approximating equations have unique solutions and these solutions converge to the solution of the original equation. For the scalar case and the spaceL
2() these conditions coincide with the strong ellipticity of the given equation.This work was fulfilled during the first author's visit to the Weierstrass Institute for Applied Analysis and Stochastics, Berlin in October 1993. 相似文献
980.
Summary.
Methods for the numerical inversion of a Laplace transform
which
use a special bilinear transformation of are particularly
effective in
many cases and are widely used.
The main purpose of this paper is to analyze the convergence
and conditioning
properties of a special class of such methods, characterized
by the use of
Lagrange interpolation. The results derived apply both to
complex and real
inversion, and show that some known inversion methods are in
fact in this
class.
Received
June 21, 1993 / Revised version received March 10, 1994 相似文献