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71.
Gan Huang  Jinde Cao  Yuzhong Qu 《Physica A》2009,388(18):3911-3916
In this paper, we focus on the effect of a network’s structure on the process of opinion formation. Emphasis is placed on the minority’s opinion evolution in a community structured network, where the majority rule is applied to govern the evolution. A model is developed for theoretical analysis using the mean field method. In this model, the connections are dense in the community, but sparse outside. A bifurcation diagram can thus be constructed, which is also verified through experimental study. The phase transition in the evolution is also investigated. In addition, a further investigation shows that a larger group size would bring more advantage to the minority.  相似文献   
72.
In this paper we present novel double gate (DG) metal oxide semiconductor field effect transistor (MOSFET) and gate all around (GAA) nanowire metal oxide semiconductor field effect transistor (NWT) with a diminished exchange-correlation (Ex-Corr) effect. The key idea in this work is to use Indium Arsenide (InAs) semiconductor instead of Si. We have evaluated and compared different parameters of DG-MOSFET and GAA-NWTs such as threshold voltage, sub-threshold slope, drain induced barrier lowering and ON and OFF state currents from quantum view. Quantum mechanical transport approach based on non-equilibrium green’s function (NEGF) has been performed in the frame work of effective mass theory in consideration with Ex-Corr effect. This simulation method consists of three dimensional Poisson’s equation in which a Schrodinger equation is first solved in each slice of the device to find Eigen energies and Eigen functions. Then, a transport equation of electrons moving in the sub-bands is solved. This fully quantum method treats such effects as source-to-drain tunneling, ballistic transport, and quantum confinement on equal footing. The results show that only a few lowest Eigen sub-bands are occupied and the upper sub-bands can be safely neglected. Also, the interaction between electrons and Ex-Corr effect is diminished in the proposed structure.  相似文献   
73.
We put forward an opinion model that considers internal decay and external activation or deactivation. Agents may withdraw from the discussion, meanwhile, these inactive agents are likely to be motivated by active neighbors. In addition, external influence from outside circumstances is added to the population. We focus on the majority rule of opinion exchange. Our investigations reveal under the impact of external circumstances, the system evolves to different stable states. One opinion can finally be made dominant when the internal motivation is large sufficiently. However, without external activation, consensus is hardly reached in the system with interest decay.  相似文献   
74.
In a (t, n) secret sharing scheme, a secret s is divided into n shares and shared among a set of n shareholders by a mutually trusted dealer in such a way that any t or more than t shares will be able to reconstruct this secret; but fewer than t shares cannot know any information about the secret. When shareholders present their shares in the secret reconstruction phase, dishonest shareholder(s) (i.e. cheater(s)) can always exclusively derive the secret by presenting faked share(s) and thus the other honest shareholders get nothing but a faked secret. Cheater detection and identification are very important to achieve fair reconstruction of a secret. In this paper, we consider the situation that there are more than t shareholders participated in the secret reconstruction. Since there are more than t shares (i.e. it only requires t shares) for reconstructing the secret, the redundant shares can be used for cheater detection and identification. Our proposed scheme uses the shares generated by the dealer to reconstruct the secret and, at the same time, to detect and identify cheaters. We have included discussion on three attacks of cheaters and bounds of detectability and identifiability of our proposed scheme under these three attacks. Our proposed scheme is an extension of Shamir’s secret sharing scheme.   相似文献   
75.
Data on the paraffinic hydrocarbon content of mussels (Mytilus edulis and M. califomianus) were analyzed statistically in an attempt to assess oil contamination of several aquatic areas of the greater Puget Sound basin in the State of Washington. The mussels were collected quarterly over a period of two years from ten locations. Fundamental statistical treatment of the data did not reveal meaningful trends. Application of pattern recognition techniques to the hydrocarbon data set allowed the mussel samples to be successfully classified into groups, from areas near known sources of potential pollution or from areas remote from known pollution. Several samples however, could not be grouped consistently as either from contaminated or uncontaminated sites. In addition, the mussels from a particular area could be separated as to season of sampling. Seasonal variation in levels of individual paraffinic hydrocarbons were greater than annual changes. The n-C16 hydrocarbon concentration was the most useful of the 34 features studied for establishing possible oil contamination of the areas. The n-C16 hydrocarbon content was also used successfully to detect oil spills and to define uncontaminated locations in Puget Sound.  相似文献   
76.
We study the majority rule transformation applied to the Gibbs measure for the 2D Ising model at the critical point. The aim is to show that the renormalized Hamiltonian is well defined in the sense that the renormalized measure is Gibbsian. We analyze the validity of Dobrushin-Shlosman uniqueness (DSU) finite-size condition for the constrained models corresponding to different configurations of the image system. It is known that DSU implies, in our 2D case, complete analyticity from which, as recently shown by Haller and Kennedy. Gibbsianness follows. We introduce a Monte Carlo algorithm to compute an upper bound to Vasserstein distance (appearing in DSU) between finite-volume Gibbs measures with different boundary conditions. We get strong numerical evidence that indeed the DSU condition is verified for a large enough volumeV for all constrained models.  相似文献   
77.
针对全场光学相干层析术实用化时成像速度不高的问题,提出一种基于FPGA控制的相位调制快速全场光学相干层析系统成像方法.首先用FPGA搭建电路以产生频率可调的高准确度正弦信号与脉冲信号,然后利用所产生的信号作为调制频率,采用四步移相法获取光学断层图像.采用该方法对洋葱表皮细胞进行光学断层成像,并与传统相移法及采用单片机调制方式获取的图像进行对比,结果表明该方法不仅能提高成像质量,且对高分辨率光学断层图像的采集时间从目前的4s(0.25 Hz)减少到0.03~0.05s(20Hz~35Hz),提高了系统的成像速度.  相似文献   
78.
We consider a game played by two players, Paul and Carol. At the beginning of the game, Carol fixes a coloring of n balls. At each turn, Paul chooses a pair of the balls and asks Carol whether the balls have the same color. Carol truthfully answers his question. Paul’s goal is to determine the most frequent (plurality) color in the coloring by asking as few questions as possible. The game is studied in the probabilistic setting when Paul is allowed to choose his next question randomly.We give asymptotically tight bounds both for the case of two colors and many colors. For the balls colored by k colors, we prove a lower bound Ω(kn) on the expected number of questions; this is asymptotically optimal. For the balls colored by two colors, we provide a strategy for Paul to determine the plurality color with the expected number of questions; this almost matches the lower bound .  相似文献   
79.
Based on the first-principles computational method and elastic scattering Green's function theory, we have investigated the effect of gate electric field on electronic transport properties of a series of single organic molecular junctions theoretically. The numerical results show that the molecular junctions that have redox centers and relatively large dipole moments parallel gate direction can respond to the gate electric field remarkably. The current-voltage properties of 2,5-dimethyl-thiophene-dithiol present N-channel-metal-oxide-semiconductor-like characteristics. Its distinct current-voltage properties can be understood from the evo-lution of eigenvalues, coupling energies, and atomic charges with gate electric field.  相似文献   
80.
针对高光谱成像需求,设计了一套可见/近红外实时成像光谱仪.光谱仪基于声光可调谐滤波器(Acousto-Optic Tunable Filter,AOTF)分光器件进行设计,光谱带宽为1.3μm,其中可见光相机工作在400~1000 nm波段,近红外相机工作在1000~1700 nm波段.光谱仪控制系统以现场可编程门阵列...  相似文献   
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