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991.
The paper proposes several mathematical models of the multidirectional associative memory (MAM) neural network by analyzing
its structure. A model of MAM with distributed delays is studied. Under some new assumptions on activation functions, 2n0[m/2]{2^{n_0[m/2]}} invariant subsets of MAM are constructed. Then the existence and the exponential stability of 2n0[m/2]{2^{n_0[m/2]}} periodic solutions located on invariant subsets are obtained by constructing a suitable Liapunov function and a Poincaré
mapping. An estimating method of the exponential convergence rate is given. The obtained results are new to MAM neural networks.
An example is given to illustrate the effectiveness of the results. 相似文献
992.
Examining mobile banking user adoption from the perspectives of trust and flow experience 总被引:2,自引:0,他引:2
Tao Zhou 《Information Technology and Management》2012,13(1):27-37
Due to the high perceived risk and poor experience associated with using mobile banking, it is critical for service providers
to build users’ trust and improve their experience. Integrating both perspectives of trust and flow experience, this research
examined the factors affecting mobile banking user adoption. The results indicate that structural assurance is the main factor
affecting trust, whereas ubiquity and perceived ease of use are the main factors affecting flow experience. Trust has a significant
effect on flow experience, and both factors determine usage intention, which in turn affects actual usage. Thus mobile service
providers need to concern both trust and flow experience to facilitate user adoption and usage of mobile banking services. 相似文献
993.
A major task of a Web GIS (Geographic Information Systems) system is to transfer map data to client applications over the
Internet, which may be too costly. To improve this inefficient process, various solutions are available. Caching the responses
of the requests on the client side is the most commonly implemented solution. However, this method may not be adequate by
itself. Besides caching the responses, predicting the next possible requests from a client and updating the cache with responses
for those requests together provide a remarkable performance improvement. This procedure is called “prefetching” and makes
caching mechanisms more effective and efficient. This paper proposes an efficient prefetching algorithm called Retrospective
Adaptive Prefetch (RAP), which is constructed over a heuristic method that considers the former actions of a given user. The
algorithm reduces the user-perceived response time and improves user navigation efficiency. Additionally, it adjusts the cache
size automatically, based on the memory size of the client’s machine. RAP is compared with four other prefetching algorithms.
The experiments show that RAP provides better performance enhancements than the other methods. 相似文献
994.
Chengcheng Zhou Kang Xue Lidan Gou Chunfang Sun Gangcheng Wang Taotao Hu 《Quantum Information Processing》2012,11(6):1765-1773
In this paper, a 3?×?3-matrix representation of Birman?CWenzl?CMurakami (BWM) algebra has been presented. Based on which, unitary matrices A(??, ?? 1, ?? 2) and B(??, ?? 1, ?? 2) are generated via Yang?CBaxterization approach. A Hamiltonian is constructed from the unitary B(??, ??) matrix. Then we study Berry phase of the Yang?CBaxter system, and obtain the relationship between topological parameter and Berry phase. 相似文献
995.
Xu Yuhua Zhou Wuneng Fang Jian-an 《International Journal of Control, Automation and Systems》2012,10(2):415-420
To simulate more realistic networks, we introduce a complex dynamical network model with double non-delayed and double delayed
coupling and further investigate its synchronization phenomenon in this paper. Based on Lyapunov stability theory, adaptive
synchronization criteria is obtained. Analytical result shows that under the designed adaptive controllers, the complex dynamical
network with double non-delayed and double delayed coupling can asymptotically synchronize to a given trajectory. What is
more, the coupling matrix is not assumed to be symmetric or irreducible. Finally, simulation results show the method is effective. 相似文献
996.
Computational modeling and simulation can provide an effective predictive capability for flow properties of the confined fluids in micro/nanoscales. In this paper, considering the boundary slip at the fluid–solid interface, the motion property of fluids confined in parallel-plate nanochannels are investigated to couple the atomistic regime to continuum. The corrected second-order slip boundary condition is used to solve the Navier–Stokes equations for confined fluids. Molecular dynamics simulations for Poiseuille flows are performed to study the influences of the strength of the solid–fluid coupling, the fluid temperature, and the density of the solid wall on the velocity slip at the fluid boundary. For weak solid–fluid coupling strength, high temperature of the confined fluid and high density of the solid wall, the large velocity slip at the fluid boundary can be obviously observed. The effectiveness of the corrected second-order slip boundary condition is demonstrated by comparing the velocity profiles of Poiseuille flows from MD simulations with that from continuum. 相似文献
997.
In level set based structural optimization, semi-Lagrange method has an advantage to allow for a large time step without the limitation of Courant–Friedrichs–Lewy (CFL) condition for numerical stability. In this paper, a line search algorithm and a sensitivity modulation scheme are introduced for the semi-Lagrange method. The line search attempts to adaptively determine an appropriate time step in each iteration of optimization. With consideration of some practical characteristics of the topology optimization process, incorporating the line search into semi-Lagrange optimization method can yield fewer design iterations and thus improve the overall computational efficiency. The sensitivity modulation is inspired from the conjugate gradient method in finite-dimensions, and provides an alternative to the standard steepest descent search in level set based optimization. Two benchmark examples are presented to compare the sensitivity modulation and the steepest descent techniques with and without the line search respectively. 相似文献
998.
Baocheng Wang Zhijun Li Wenjun Ye Qing Xie 《International Journal of Control, Automation and Systems》2012,10(6):1225-1231
Human-robot control interfaces have received increased attention during the past decades for conveniently introducing robot into human daily life. In this paper, a novel Human-machine Interface (HMI) is developed, which contains two components. One is based on the surface electromyography (sEMG) signal, which is from the human upper limb, and the other is based on the Microsoft Kinect sensor. The proposed interface allows the user to control in real time a mobile humanoid robot arm in 3-D space, through upper limb motion estimation by sEMG recordings and Microsoft Kinect sensor. The effectiveness of the method is verified by experiments, including random arm motions in the 3-D space with variable hand speed profiles. 相似文献
999.
G. I. N. Rozvany M. Zhou M. Rotthaus W. Gollub F. Spengemann 《Structural and Multidisciplinary Optimization》1989,1(1):47-72
Continuum-type optimality criteria for the iterative optimization of large finite element systems (i.e. systems with over ten thousand finite elements) are discussed. By investigating optimization problems with up to one million elements and one million variables, it is shown that for a single displacement constraint the proposed method results in a rapid and almost uniform convergence, the rate of which, even for relatively ill-conditioned problems, does not depend significantly on the number of elements. Additional refinements, including upper and lower limits on the cross-sectional dimensions, segmentation, allowance for selfweight and the cost of supports, non-linear and non-separable objective functions, inclusion of shear deformations, built-up cross-sections as well as additional stress constraints and two-dimensional (plane stress) problems, will be considered in Part II of this contribution. The current development constitutes an extension and generalization of pioneering work by Berke, Khot, Venkayya and their associates, whose methods are also reviewed herein. In addition to an elementary truss example and a more advanced beam example, some simple layout optimization problems are considered in this Part. A special feature of the paper is that all numerical results presented are confirmed by closed form analytical solutions. 相似文献
1000.
Equations of state and contact values of hard-sphere radial distribution functions (rdf's) which are given by a linear combination of the Percus— Yevick and scaled-particle virial expressions are considered. In the one-component case the mixing coefficient() is, in general, a function of the volume fraction. In mixtures the coefficient(
i
,d
i
), in general, depends upon the volume fraction
i
, and diameterd
i
, of each species,i andj. For the contact valuesY
ij
of the rdf's, the mixing coefficients
ij
(
k
) also depend on speciesi andj. Density expansions for the exact for the one-component hard-sphere fluid are obtained and compared with several approximations made in earlier works and in our own work, as well as with simulations. For a mixture, it turns out that one cannot obtain the exact fourth virial coefficient by using a linear combination of the Percus-Yevick and scaled-particle virial expressions forY
ij
unless one allows
ij
to depend on mole fractionsx
i
even at the zeroth order of its density expansion. We also find that
ij
must depend on particle speciesi andj in order to satisfy the exact limits obtained earlier by Sung and Stell. A new equation of state for the binary hard-sphere mixture which satisfies all the exact limits we have considered is suggested.Paper presented at the Tenth Symposium on Thermophysical Properties, June 20–23, 1988, Gaithersburg, Maryland, U.S.A. 相似文献