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781.
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783.
Souvik Sengupta Jordi Garcia Xavi Masip‐Bruin 《International Journal of Communication Systems》2020,33(10)
Fog‐to‐cloud (F2C) computing is an emerging computational platform. By combing the cloud, fog, and IoT, it provides an excellent framework for managing and coordinating the resources in any smart computing domain. Efficient management of these kinds of diverse resources is one of the critical tasks in the F2C system. Also, it must be considered that different types of services are offered by any smart system. So, before managing these resources and enabling the various types of services, it is essential to have some comprehensive informational catalogue of resources and services. Hence, after identifying the resource and service‐task taxonomy, our main aim in this paper is finding out a solution for properly organizing this information over the F2C system. For that purpose, we are proposing a modified F2C framework where all the information is distributively stored near to the edge of the network. Finally, by presenting some experimental results, we evaluate and validate the performance of our proposing framework. 相似文献
784.
Souvik Mondal Durga Sankar Chowdhuri Soumen Ghosh Ajay Misra Sudipta Dalai 《Journal of Molecular Structure》2007,810(1-3):81-89
DFT calculations has been done applying 6-31G* basis set on a series of dipeptides where the N-terminus position is fixed with phenylalanine and the C-terminus is varied with eight different amino acids. Different geometrical parameters (bond angle, bond length, geometry around -carbon atom) are thoroughly investigated to study the effect of amino acid sequence on dipeptide. Dihedral angle data analysis shows the deviation of amide plane from planarity, which is due to the combined effect of the steric hindrance of –R group and hydrogen bonding. The λmax value for phenylalanine has been calculated, which shows good agreement with the experimental value. A rigid potential energy scan is performed on phenylalanine by rotating –CH2Ph, –COOH and –NH2 groups separately to get some idea about the conformational stability. 相似文献
785.
Sengupta Soumitra K. Pandey Om P. Srivastava Akhilesh K. Bhatt Alpana Mishra Kushal N. 《Transition Metal Chemistry》1999,24(6):703-707
The reactions of Cp2>HfCl2> with hydrazones (LH) derived from acetylferrocene and aromatic acid hydrazides (benzoic, 2-chlorobenzoic, 3-nitrobenzoic and 4-toluic) in various stoichiometric ratios have been studied and the complexes of the types [Cp2>Hf(L)Cl] and [CpHf(L)3>] were obtained. Tentative structural conclusions are drawn for the reaction products based upon elemental analyses, electrical conductance, magnetic moment and spectral data (u.v.–vis, i.r., 1>H-n.m.r. and 13>C-n.m.r.). Studies were conducted to assess the growth-inhibiting potential of the complexes synthesized, and the ligands, against various fungal and bacterial strains. 相似文献
786.
Two-phase routing, where traffic is first distributed to intermediate nodes before being routed to the final destination, has been recently proposed for handling widely fluctuating traffic without the need to adapt network routing to changing traffic. Preconfiguring the network in a traffic independent manner using two-phase routing simplifies network operation considerably. In this paper, we extend this routing scheme by providing resiliency against link failures through fast restoration along link backup detours. We view this as important progress towards adding carrier-class reliability to the robustness of the scheme so as to facilitate its future deployment in Internet Service Provider (ISP) networks. On the theoretical side, the main contribution of the paper is the development of linear programming based and fast combinatorial algorithms for two-phase routing with link restoration so as to minimize the maximum utilization of any link in the network, or equivalently, maximize the throughput. The algorithms developed are fully polynomial time approximation schemes (FPTAS)-for any given isin > 0, an FPTAS guarantees a solution that is within a (1 + isin)-factor of the optimum and runs in time polynomial in the input size and 1/isin. To the best of our knowledge, this is the first work in the literature that considers making the scheme resilient to link failures through preprovisioned fast restoration mechanisms. We evaluate the performance of link restoration (in terms of throughput) and compare it with that of unprotected routing. For our experiments, we use actual ISP network topologies collected for the Rocketfuel project and three research network topologies. 相似文献
787.
Susanta K. Sengupta Urvashi Sandhir Nira Misra 《Journal of polymer science. Part A, Polymer chemistry》2001,39(10):1584-1588
Contact glow-discharge electrolysis (CGDE) is an unconventional electrolytic phenomenon in which a plasma is sustained by a direct current (dc) glow-discharge between an electrode and the liquid electrolyte around it. A remarkable feature of CGDE is highly nonfaradaic chemical effects at the glow-discharge electrode. During anodic CGDE of an aqueous electrolyte, non-Faradaic yields originate mainly from reactions triggered by H• and OH• radicals generated in high local concentrations near the anodic plasma/liquid electrolyte interface during the process. The radical-generating potentiality of anodic CGDE was explored for the polymerization of acrylamide in aqueous media. The percentage of monomer conversion, rate of polymerization, charge efficiency, and viscometric average molar mass of the polymers produced were measured as functions of the quantities of electricity passed. The charge efficiency of the polymerization of acrylamide by anodic CGDE was at least 1 order of magnitude higher than that of ordinary electrochemically initiated polymerization. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1584–1588, 2001 相似文献
788.
Two-phase routing, where traffic is first distributed to intermediate nodes before being routed to the final destination, has been recently proposed for handling widely fluctuating traffic without the need to adapt network routing to changing traffic. Preconfiguring the network in a traffic-independent manner using two-phase routing simplifies network operation considerably. In this paper, we extend this routing scheme by providing resiliency against link failures through fast path restoration along disjoint end-to-end backup paths. We view this as important progress toward adding carrier-class reliability to the robustness of the scheme so as to facilitate its future deployment in Internet service provider (ISP) networks. On the theoretical side, the main contribution of the paper is the development of linear-programming-based and fast combinatorial algorithms for two-phase routing with fast path restoration so as to minimize the maximum utilization of any link in the network, or equivalently, maximize the throughput. The algorithms developed are fully polynomial time approximation schemes (FPTAS)-for any given epsiv > 0, an FPTAS guarantees a solution that is within a (1+epsiv)-factor of the optimum and runs in time polynomial in the input size and [ 1/(relax epsiv)]. To the best of our knowledge, this is the first work in the literature that considers making the scheme resilient to link failures through preprovisioned fast restoration mechanisms. We evaluate the performance of fast path restoration (in terms of throughput) and compare it to that of unprotected routing. For our experiments, we use actual ISP network topologies collected for the Rocketfuel project and three research network topologies. 相似文献
789.
Machine reliability and preventive maintenance planning for cellular manufacturing systems 总被引:1,自引:0,他引:1
The paper proposes a preventive maintenance (PM) planning model for the performance improvement of cellular manufacturing systems (CMS) in terms of machine reliability, and resource utilization. In a CMS, parts are processed by a group of interdependent machines, where machine reliability plays an important role in the performance improvement of the cell. Assuming that machine failure times follow a Weibull distribution, the proposed model determines a PM interval and a schedule for performing PM actions on each machine in the cell by minimizing the total maintenance cost and the overall probability of machine failures. The model uses a combined cost and reliability based approach, and optimizes maintenance costs by administering a group maintenance policy subject to a desirable machine reliability threshold. The study also proposes a CMS design model that integrates the above PM concepts into the design process. Illustrative examples are presented to demonstrate the applicability of the proposed approach. 相似文献
790.
This paper presents an analytical solution to the problem of the optimal rendezvous using power-limited propulsion for a spacecraft
in an elliptic orbit in a gravitational field. The derivation of the result assumes small relative distances, but does not
make any assumption on the eccentricity of the orbit and does not require numerical integration. The results are generalized
to include the possibility of different weights on the control effort for each axis (radial, along-track, and out-of-plane).
When the weights on the control efforts are unequal, several integrals are used whose solutions may be represented by infinite
series in a small parameter dependent on the eccentricity. A methodology is introduced where the series can be extended trivially
to as many terms as desired. Furthermore, for a given numerical tolerance, an upper bound on the number of terms required
to represent the series is also obtained. When the weights are equal for all the three axes, the series representations are
no longer necessary. The results can be used easily to design optimal feedback controls for rendezvous maneuvers, or for generating
initial guesses for two-point boundary-value problems for numerical solutions to the nonlinear rendezvous problem. 相似文献