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921.
In this paper we analyze a queueing system with a general service scheduling function. There are two types of customer with different service requirements. The service order for customers of each type is determined by the service scheduling function αk(i, j) where αk(i, j) is the probability for type-k customer to be selected when there are i type-1 and j type-2 customers. This model is motivated by traffic control to support traffic streams with different traffic characteristics in telecommunication networks (in particular, ATM networks). By using the embedded Markov chain and supplementary variable methods, we obtain the queue-length distribution as well as the loss probability and the mean waiting time for each type of customer. We also apply our model to traffic control to support diverse traffics in telecommunication networks. Finally, the performance measures of the existing diverse scheduling policies are compared. We expect to help the system designers select appropriate scheduling policy for their systems. 相似文献
922.
将存在多个工作环境的加速度计组合件温度控制受控对象描述为存在有界时变参数摄动和有界干扰的非线性时变不确定系统,提出了一种基于信号补偿的鲁棒温度控制方法,该方法设计的控制器由标称控制器和鲁棒补偿器组成.证明了闭环系统的鲁棒控制特性,实验结果显示所设计的控制系统能够在多个工作环境下实现高精度的鲁棒温度控制. 相似文献
923.
924.
Motivated by a simple optimal control problem with state constraints, we consider an inexact implementation of the primal-dual interior point algorithm of Zhang, Tapia, and Dennis. We show how the control problem can be formulated as a linear program in an infinite dimensional space in two different ways and prove convergence results.The research of this author was supported by an Overseas Research Scholarship of the Ministry of Education, Science and Culture of Japan.The research of this author was supported by National Science Foundation grants #DMS-9024622 and #DMS-9321938, North Atlantic Treaty Organization grant #CRG 920067, and an allocation of computing resources from the North Carolina Supercomputing Program.The research of this author was supported by North Atlantic Treaty Organization grant #CRG 920067. 相似文献
925.
Motivated by ABR class of service in ATM networks, we study a continuous time queueing system with a feedback control of the
arrival rate of some of the sources. The feedback about the queue length or the total workload is provided at regular intervals
(variations on it, especially the traffic management specification TM 4.0, are also considered). The propagation delays can
be nonnegligible. For a general class of feedback algorithms, we obtain the stability of the system in the presence of one
or more bottleneck nodes in the virtual circuit. Our system is general enough that it can be useful to study feedback control
in other network protocols. We also obtain rates of convergence to the stationary distributions and finiteness of moments.
For the single botterneck case, we provide algorithms to compute the stationary distributions and the moments of the sojourn
times in different sets of states. We also show analytically (by showing continuity of stationary distributions and moments)
that for small propagation delays, we can provide feedback algorithms which have higher mean throughput, lower probability
of overflow and lower delay jitter than any open loop policy. Finally these results are supplemented by some computational
results.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
926.
用集成电路制成程序控制器,示教板性能稳定,寿命长,效果好,操作方便.其主要部分由电源、时钟、逻辑电路、输出驱动器四部分组成. 相似文献
927.
Manuel de León 《Reports on Mathematical Physics》2004,53(1):55-78
In this paper we study general symmetries for optimal control problems making use of the geometric formulation proposed in [7]. This framework allows us to reduce the number of equations associated with optimal control problems with symmetry and compare the solutions of the original system with the solutions of the reduced one. The reconstruction of the optimal controls starting from the reduced problem is also explored. 相似文献
928.
929.
Multi-Armed bandit problem revisited 总被引:1,自引:0,他引:1
In this paper, we revisit aspects of the multi-armed bandit problem in the earlier work (Ref. 1). An alternative proof of the optimality of the Gittins index rule is derived under the discounted reward criterion. The proof does not involve an explicit use of the interchange argument. The ideas of the proof are extended to derive the asymptotic optimality of the index rule under the average reward criterion. Problems involving superprocesses and arm-acquiring bandits are also reexamined. The properties of an optimal policy for an arm-acquiring bandit are discussed.This research was supported by NSF Grant IRI-91-20074. 相似文献
930.
Jos M. Asua 《Journal of polymer science. Part A, Polymer chemistry》2004,42(5):1025-1041
Emulsion polymers are “products by process” whose main properties are determined during polymerization. In this scenario of margins reduction, increasing competition, and public sensitivity to environmental issues, the challenge is to achieve an efficient production of high‐quality materials in a consistent, safe, and environmentally friendly way. This highlight reviews the investigations carried out at The University of the Basque Country to develop a knowledge‐based strategy to achieve these goals. First, the research in fundamental mechanisms is discussed. This includes studies in radical entry and exit, oil‐soluble initiators, propagation‐rate constants of acrylic monomers, processes involved in the formation of branched and crosslinked polymers, microstructure modification by postreaction operations, the formation of particle morphology, and reactive surfactants. The advanced mathematical models developed in the group are also reviewed. In the second part, the advances in process development (optimization, online monitoring and control, monomer removal, production of high‐solids, low‐viscosity latices, and process intensification) are presented. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1025–1041, 2004 相似文献