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141.
R. Ben Hassen A. Ben Salah A. Kallel A. Daoud J. Jaud 《Journal of chemical crystallography》2002,32(11):427-430
CH3NH3CdBr3 crystallizes in the space group Ccm21, a = 13.693(1) Å, b = 7.906(1) Å, c = 6.886(1) Å, V = 745.46(15) Å3, Z = 4, D
x
= 3.42 Mg m–3. The structure of the title compound is one-dimensional consisting of infinite chains made of face sharing CdBr6 octahedra. The methylammonium groups are situated in the space between chains. The cations and anions are joined by hydrogen bonding. 相似文献
142.
Sandra Fortini Lucia Ladelli Giovanni Petris Eugenio Regazzini 《Stochastic Processes and their Applications》2002,100(1-2):147-165
Let X be a chain with discrete state space I, and V be the matrix of entries Vi,n, where Vi,n denotes the position of the process immediately after the nth visit to i. We prove that the law of X is a mixture of laws of Markov chains if and only if the distribution of V is invariant under finite permutations within rows (i.e., the Vi,n's are partially exchangeable in the sense of de Finetti). We also prove that an analogous statement holds true for mixtures of laws of Markov chains with a general state space and atomic kernels. Going back to the discrete case, we analyze the relationships between partial exchangeability of V and Markov exchangeability in the sense of Diaconis and Freedman. The main statement is that the former is stronger than the latter, but the two are equivalent under the assumption of recurrence. Combination of this equivalence with the aforesaid representation theorem gives the Diaconis and Freedman basic result for mixtures of Markov chains. 相似文献
143.
Vivek S. Borkar 《Annals of Operations Research》1991,29(1):429-438
A new state variable is introduced for the problem of controlling a Markov chain under partial observations, which, under a suitably altered probability measure, has a simple evolution. 相似文献
144.
Heyman gives an interesting factorization of I-P, where P is the transition probability matrix for an ergodic Markov chain. We show that this factorization is valid if and only if
the Markov chain is recurrent. Moreover, we provide a decomposition result which includes all ergodic, null recurrent as well
as the transient Markov chains as special cases. Such a decomposition has been shown to be useful in the analysis of queues.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
145.
Revindra M. Phatarfod 《Stochastic Processes and their Applications》1982,13(3):279-292
It is known that the main difficulty in applying the Markovian analogue of Wald's Identity is the presence, in the Identity, of the last state variable before the random walk is terminated. In this paper we show that this difficulty can be overcome if the underlying Markov chain has a finite state space. The absorption probabilities thus obtained are used, by employing a duality argument, to derive time-dependent and limiting probabilities for the depletion process of a dam with Markovian inputs.The second problem that is considered here is that of a non-homogeneous but cyclic Markov chain. An analogue of Wald's Identity is obtained for this case, and is used to derive time- dependent and limiting probabilities for the depletion process with inputs forming a non- homogeneous (cyclic) Markov chain. 相似文献
146.
We study the properties of finite ergodic Markov Chains whose transition probability matrix P is singular. The results establish bounds on the convergence time of Pm to a matrix where all the rows are equal to the stationary distribution of P. The results suggest a simple rule for identifying the singular matrices which do not have a finite convergence time. We next study finite convergence to the stationary distribution independent of the initial distribution. The results establish the connection between the convergence time and the order of the minimal polynomial of the transition probability matrix. A queuing problem and a maintenance Markovian decision problem which possess the property of rapid convergence are presented. 相似文献
147.
E. Bolthausen 《Stochastic Processes and their Applications》1979,9(2):217-222
Let Xn be an irreducible aperiodic recurrent Markov chain with countable state space I and with the mean recurrence times having second moments. There is proved a global central limit theorem for the properly normalized sojourn times. More precisely, if , then the probability measures induced by {t(n)i/√n?√nπi}i?I(πi being the ergotic distribution) on the Hilbert-space of square summable I-sequences converge weakly in this space to a Gaussian measure determined by a certain weak potential operator. 相似文献
148.
June?DongEmail author Ding?Zhang Hong?Yan Anna?Nagurney 《Annals of Operations Research》2005,135(1):155-178
In this paper, we present a supply chain network model with multiple tiers of decision-makers, consisting, respectively, of
manufacturers, distributors, and retailers, who can compete within a tier but may cooperate between tiers. We consider multicriteria
decision-making for both the manufacturers and the distributors whereas the retailers are subject to decision-making under
uncertainty since the demands associated with the product are random. We derive the optimality conditions for the decision-makers,
establish the equilibrium conditions, and derive the variational inequality formulation. We then utilize the variational inequality
formulation to provide both qualitative properties of the equilibrium product shipment, service level, and price pattern and
to propose a computational procedure, along with convergence results. This is the first supply chain network model to capture
both multicriteria decision-making and decision-making under uncertainty in an integrated equilibrium framework. 相似文献
149.
John F. Nagle 《Journal of statistical physics》1985,38(3-4):531-540
It has been suggested that some lattice models of polymers, especially ones that incorporate more realistic excluded volume interactions extending to further neighbors, may be subject to gridlock. A model is defined to have the property of gridlock if it cannot melt at any temperature unless a density decrease is allowed. Classical theories of polymer melting are incompatible with the property of gridlock. This paper proves rigorously that a two-dimensional square-lattice model of polymer chains that have nearest-neighbor excluded volume interactions (called the X1S model) has the gridlock property. The proof uses elementary concepts from graph theory. Also, different interpretations of the X1S model are given in terms of real polymers. This leads to a discussion of a number of different classes of melting depending upon whether the intramolecular rotameric energies and the attractive intermolecular energies are antagonistic to or supportive of the melting transition. 相似文献
150.
Dan Teodorescu 《Stochastic Processes and their Applications》1980,10(3):255-270
A new class of operators performing an optimization (optimization operators or, simply, optimators) which generate transition matrices with required properties such as ergodicity, recurrence etc., is considered and their fundamental features are described. Some criteria for comparing such operators by taking into account their strenght are given and sufficient conditions for both weak and strong ergodicity are derived. The nearest Markovian model with respect to a given set of observed probability vectors is then defined as a sequence of transition matrices satisfying certain constraints that express our prior knowledge about the system. Finally, sufficient conditions for the existence of such a model are given and the related algorithm is illustrated by an example. 相似文献