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901.
提出利用线性判别函数,d(x)=W'x,对轰炸机和战斗机两类目标进行旋转不变识别。每一目标有72个旋转模式,其中9个为训练样本,63个为测试样本,在每个目标的训练样本中随机取一个相减作为线性判别函数的系数(Wij)的初始值,然后利用误判的训练样本优化判别函数的权值以提高函数的正确识别率。为便于光电实现,线性判别函数的权值系数只有2、1、0、-1、-2五个值。计算机模拟表明利用此判别函数进行分类的正 相似文献
902.
Federico Incitti 《Journal of Combinatorial Theory, Series A》2006,113(7):1332-1350
In this paper, we solve the conjecture about the combinatorial invariance of Kazhdan-Lusztig polynomials for the first open cases, showing that it is true for intervals of length 5 and 6 in the symmetric group. We also obtain explicit formulas for the R-polynomials and for the Kazhdan-Lusztig polynomials associated with any interval of length 5 in any Coxeter group, showing in particular what they look like in the symmetric group. 相似文献
903.
Wei Chen 《计算数学(英文版)》2002,(4)
AbstractThis paper discuss band-limited scaling function, especially on the interval band case and three interval bands case, its relationship to oversampling property and weakly translation invariance are also studied. At the end, we propose an open problem. 相似文献
904.
The First-Order Nonholonomic Connections with the Galilean Groups of Local Transformations. III 总被引:1,自引:1,他引:0
In the canonical smooth fiber bundles
endowed with the metric tensor fields of relevant structure, we consider natural representations of the Galilean groups
(1, n) and construct
(1, n)-invariant generalized differential-geometric connections. In both regular and special cases of the representations of the considered groups
(1, n), we find all affine nonholonomic
, and 1,2-connections of the first order (see [1]–[3]) possessing the local Lie groups of transformations
(1, n) and also describe the corresponding
(1, n)invariant planar connections. 相似文献
905.
Necessary and Sufficient Condition for the Functional Central Limit Theorem in Hölder Spaces 总被引:2,自引:0,他引:2
Let (X
i
)
i1 be an i.i.d. sequence of random elements in the Banach space B, S
n
X
1++X
n
and
n
be the random polygonal line with vertices (k/n,S
k
), k=0,1,...,n. Put (h)=h
L(1/h), 0h1 with 0<1/2 and L slowly varying at infinity. Let H
0
(B) be the Hölder space of functions x:[0,1]B, such that x(t+h)–x(t)=o((h)), uniformly in t. We characterize the weak convergence in H
0
(B) of n
–1/2
n
to a Brownian motion. In the special case where B= and (h)=h
, our necessary and sufficient conditions for such convergence are E
X
1=0 and P(|X
1|>t)=o(t
–p()) where p()=1/(1/2–). This completes Lamperti (1962) invariance principle. 相似文献
906.
Rafael D Benguria Isabelle Catto Jean Dolbeault Régis Monneau 《Journal of Differential Equations》2004,205(1):253-269
By variational methods, we prove the inequality
907.
To a pair (G, G) of ADE Dynkin diagrams one can associate five types of sesquilinear forms on the space of Virasoro characters. These forms can be interpreted, in terms of minimal models, as twisted partition functions. Our classification rests on the possibility of twisting the torus structures of the two diagrams G and G. For the torus structure of a given diagram, one can introduce a single twist, two twists, or no twist at all. We describe the general situation and study an example pertaining to the case of the Virasoro minimal models. 相似文献
908.
Artur B. Adib 《Journal of statistical physics》2004,117(3-4):581-597
In an attempt to derive thermodynamics from classical mechanics, an approximate expression for the equilibrium temperature of a finite system has been derived (M. Bianucci, R. Mannella, B. J. West and P. Grigolini, Phys. Rev. E
51: 3002 (1995)) which differs from the one that follows from the Boltzmann principle S = kln(E) via the thermodynamic relation 1/T=S / E by additional terms of dynamical character, which are argued to correct and generalize the Boltzmann principle for small systems (here (E) is the area of the constant-energy surface). In the present work, the underlying definition of temperature in the Fokker–Planck formalism of Bianucci et al., is investigated and shown to coincide with an approximate form of the equipartition temperature. Its exact form, however, is strictly related to the volume entropy S = k ln (E) via the thermodynamic relation above for systems of any number of degrees of freedom ((E) is the phase space volume enclosed by the constant-energy surface). This observation explains and clarifies the numerical results of Bianucci et al., and shows that a dynamical correction for either the temperature or the entropy is unnecessary, at least within the class of systems considered by those authors. Explicit analytical and numerical results for a particle coupled to a small chain (N~10) of quartic oscillators are also provided to further illustrate these facts. 相似文献
909.
Singularities of Centre Symmetry Sets 总被引:2,自引:0,他引:2
The center symmetry set (CSS) of a smooth hypersurface S inan affine space Rn is the envelope of lines joining pairs ofpoints where S has parallel tangent hyperplanes. The idea stemsfrom a definition of Janeczko, in an alternative version dueto Giblin and Holtom. For n = 2 the envelope is always real,while for n > 3 the existence of a real envelope dependson the geometry of the hypersurface. In this paper we make alocal study of the CSS, some results applying to n 5 and othersto the cases n = 2,3. The method is to construct a generatingfunction whose bifurcation set contains the CSS and possiblysome other redundant components. Focal sets of smooth hypersurfacesare a special case of the construction, but the CSS is an affineand not a euclidean invariant. Besides the familiar local formsof focal sets there are other local forms corresponding to boundarysingularities, and yet others which do not appear to have arisenelsewhere in a geometrical context. There are connections withFinsler geometry. This paper concentrates on the theory andthe proof of the local normal forms for the CSS. 2000 MathematicsSubject Classification 57R45, 58K40, 32S25, 58B20. 相似文献
910.
With regard to applications in quantum theory, we consider the classical wave equation involving the scalar curvature with an arbitrary coefficient . General properties of this equation and its solutions are studied based on modern results in group analysis with the aim to fix a physically justified value of . These properties depend essentially not only on the values of and the mass parameter but also on the type and dimension of the space. Form invariance and conformal invariance must be distinguished in general. A class of Lorentz spaces in which the massless equation satisfies the Huygens principle and its Green's function is free of a logarithmic singularity exists only for the conformal value of . The same value of follows from other arguments and the relation to the known WKB transformation method that we establish. 相似文献