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41.
The convexification of a noninferior frontier can be achieved in an appropriate equivalent objective space for general nonconvex multiobjective optimization problems. Specifically, this paper proves that taking the exponentials of the objective functions can act as a convexification scheme. This convexification scheme further leads to the exponential generating method that guarantees the identification of the entire set of noninferior solutions. 相似文献
42.
We consider a single server retrial queueing system in which each customer (primary or retrial customer) has discrete service times taking on value Dj with probability , and . An arriving primary customer who finds the server busy tries later. Moreover, each retrial customer has its own orbit, and the retrial customers try to enter the service independently of each other. We call this retrial queue an M/{Dn}/1 retrial queue. A necessary and sufficient condition for this system stability is given. In the steady state, we derive the joint distribution of the state of the server and the number of customers in the retrial orbits. The explicit expressions of some performance measures are given. In addition, the steady-state distribution of the waiting time is discussed. 相似文献
43.
44.
Single line queue with repeated demands 总被引:2,自引:0,他引:2
K. Farahmand 《Queueing Systems》1990,6(1):223-228
We analyze a model of a queueing system in which customers can only call in to request service: if the server is free, the
customer enters service immediately, but if the service system is occupied, the unsatisfied customer must break contact and
reinitiate his request later. Such a customer is said to be in “orbit”. In this paper we consider three models characterized
by the discipline governing the order of re-request of service from orbit. First, all customers in orbit can reapply, but
are discouraged and reduce their rate of demand as more customers join the orbit. Secondly, the FCFS discipline operates for
the unsatisfied customers in orbit. Finally, the LCFS discipline governs the customers in orbit and the server takes an exponentially
distributed vacation after each service is completed. We calculate several characteristics quantities of such systems, assuming
a general service-time distribution and different exponential distributions for the times between arrivals of first and repeat
requests. 相似文献
45.
MacMahon’s definition of self-inverse composition is extended ton-colour self-inverse composition. This introduces four new sequences which satisfy the same recurrence relation with different
initial conditions like the famous Fibonacci and Lucas sequences. For these new sequences explicit formulas, recurrence relations,
generating functions and a summation formula are obtained. Two new binomial identities with combinatorial meaning are also
given. 相似文献
46.
47.
We define a new statistic on the even hyperoctahedral groups which is a natural analogue of the odd length statistic recently defined and studied on Coxeter groups of types and . We compute the signed (by length) generating function of this statistic over the whole group and over its maximal and some other quotients and show that it always factors nicely. We also present some conjectures. 相似文献
48.
We present two conjectures concerning the diameter of a direct power of a finite group. The first conjecture states that the diameter of Gn with respect to each generating set is at most n(|G|?rank(G)); and the second one states that there exists a generating set 𝒜, of minimum size, for Gn such that the diameter of Gn with respect to 𝒜 is at most n(|G|?rank(G)). We will establish evidence for each of the above mentioned conjectures. 相似文献
49.
一类扩展Euler和的表示问题 总被引:1,自引:0,他引:1
应用Parseval定理和Nielsen广义多重对数函数的性质,给出了非线性扩展Euler和的Riemann Zeta函数表示.对来自于实验数学中的扩展Euler和∑n=1∞H2n/n2的经验公式给出了严格的理论证明.此方法也适用于求其它扩展Euler和的计算问题. 相似文献
50.
lie Panafieu 《Random Structures and Algorithms》2019,55(2):427-495
We enumerate the connected graphs that contain a number of edges growing linearly with respect to the number of vertices. So far, only the first term of the asymptotics and a bound on the error were known. Using analytic combinatorics, that is, generating function manipulations, we derive a formula for the coefficients of the complete asymptotic expansion. The same result is derived for connected multigraphs. 相似文献