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991.
G.Ch. Pflug A. Świętanowski E. Dockner H. Moritsch 《Annals of Operations Research》2000,99(1-4):189-206
The AURORA financial management system under development at the University of Vienna is a modular decision support tool for portfolio and asset–liability management. It is based on a multivariate Markovian birth-and-death factor model for the economic environment, a pricing model for the financial instruments and an objective function which is flexible enough to express risk aversion.The core of the system is a large scale linear or convex program, which due to its size and structure is well suited for parallel optimization methods.As the system is still at an early stage of development, the results are preliminary in nature. Only a few types of financial instruments are handled and just two types of objectives are considered. The parallel optimization modules are still in the development phase. 相似文献
992.
Micropolar and micromorphic solids are continuum mechanics models, which take into account, in some sense, the microstructure of the considered real material. The characteristic property of such continua is that the state functions depend, besides the classical deformation of the macroscopic material body, also upon the deformation of the microcontinuum modeling the microstructure, and its gradient with respect to the space occupied by the material body. While micropolar plasticity theories, including non-linear isotropic and non-linear kinematic hardening, have been formulated, even for non-linear geometry, few works are known yet about the formulation of (finite deformation) micromorphic plasticity. It is the aim of the three papers (Parts I, II, and III) to demonstrate how micromorphic plasticity theories may be formulated in a thermodynamically consistent way.In the present article we start by outlining the framework of the theory. Especially, we confine attention to the theory of Mindlin on continua with microstructure, which is formulated for small deformations. After precising some conceptual aspects concerning the notion of microcontinuum, we work out a finite deformation version of theory, suitable for our aims. It is examined that resulting basic field equations are the same as in the non-linear theory of Eringen, which deals with a different definition of the microcontinuum. Furthermore, geometrical interpretations of strain and curvature tensors are elaborated. This allows to find out associated rates in a natural manner. Dual stress and double stress tensors, as well as associated rates, are then defined on the basis of the stress powers. This way, it is possible to relate strain tensors (respectively, micromorphic curvature tensors) and stress tensors (respectively, double stress tensors), as well as associated rates, independently of the particular constitutive properties. 相似文献
993.
R. Rojas-Díaz A. Sáez F. García-Sánchez Ch. Zhang 《International Journal of Solids and Structures》2008,45(1):144-158
Two-dimensional (2-D) and three-dimensional (3-D) time-harmonic Green’s functions for linear magnetoelectroelastic solids are derived in this paper by means of Radon-transform. Displacement field and electric and magnetic potentials in a fully anisotropic magnetoelectroelastic infinite solid due to a time-harmonic point force, point charge and magnetic monopole are obtained in form of line integrals over a unit circle in 2-D case and surface integrals over a unit sphere in 3-D case. This dynamic fundamental solution is then split into the sum of regular dynamic plus singular terms. The singular terms coincide with the Green’s functions for the static problem and may be further reduced to closed form expressions. The proposed Green’s functions can be used in the corresponding boundary element method (BEM) formulation. 相似文献
994.
Scenario tree generation for multiperiod financial optimization by optimal discretization 总被引:1,自引:0,他引:1
G.Ch. Pflug 《Mathematical Programming》2001,89(2):251-271
Multiperiod financial optimization is usually based on a stochastic model for the possible market situations. There is a rich
literature about modeling and estimation of continuous-state financial processes, but little attention has been paid how to
approximate such a process by a discrete-state scenario process and how to measure the pertaining approximation error.?In
this paper we show how a scenario tree may be constructed in an optimal manner on the basis of a simulation model of the underlying
financial process by using a stochastic approximation technique. Consistency relations for the tree may also be taken into
account.
Received: December 15, 1998 / Accepted: October 1, 2000?Published online December 15, 2000 相似文献
995.
996.
Chávez-Casillas Jonathan A. Elliott Robert J. Rémillard Bruno Swishchuk Anatoliy V. 《Methodology and Computing in Applied Probability》2019,21(3):699-719
We propose a simple stochastic model for the dynamics of a limit order book, extending the recent work of Cont and de Larrard (SIAM J Financial Math 4(1), 1–25 2013), where the price dynamics are endogenous, resulting from market transactions. We also show that the conditional diffusion limit of the price process is the so-called Brownian meander.
相似文献997.
998.
Chávez-Díaz Mercedes P. Luna-Sánchez Rosa M. Vazquez-Arenas Jorge Lartundo-Rojas Luis Hallen José M. Cabrera-Sierra Román 《Journal of Solid State Electrochemistry》2019,23(11):3187-3196
Journal of Solid State Electrochemistry - The passivation mechanism of the film formed on the alloy Ti-6Al-4V was evaluated in Hank’s solution to infer the properties of this alloy as an... 相似文献
999.
Experimental Mechanics - Background: Despite a wealth of literature on medical high-intensity focused ultrasound (HIFU), there are knowledge gaps related to therapeutic ultrasound in the presence... 相似文献
1000.