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1.
Two kinds of noise strategies in binary opinion dynamics on ER random networks are discussed. Random noise p1 in the initial configuration plays a role in redistributing the opinion states associated with the network. Under synchronous updating, the system can attain a stable state within few time steps. The fraction of nodes with changed opinion states F decreases exponentially with time, and the ratio of one of the two opinion states R remains almost unchanged during the evolution. The average ratio c...  相似文献   

2.
With a dynamic Monte Carlo simulation, which is free of critical slowing down, the critical behavior of two-dimensional Ising model at non-equilibrium states is investigated. We focus on the two-time autocorrelation function A(t, t' ) to identify the dynamic exponent z in two different evolution stages, quenched from a high temperature state and a completely ordered state to the critical state at TC, re-spectively. By using the heat-bath algorithm, the dynamic critical exponent is estimated as z ≈ 2.16. As a result, the universality of the scaling behavior is verified numerically, and the exponent λC is deter-mined complete by λC = β /ν for the evolutions from an initial completely ordered state.  相似文献   

3.
In order to remove the fluctuating atmospheric effects from the Case 2 water, an algorithm for retrieval of suspended sediment concentration from NOAA weather satellite imagery was developed under a new approach. This model is based on the linear response from water-leaving to satellite-detected reflectance spectra, simply reflected by the gradient for correlation curve between reflectance of the advanced very high resolution radiometer (AVHRR) channels 1 (R1, 580–680 nm) and 2R 2, 720–1100 nm). Proportional factor for this gradient transiting, mathematically represented as (td2÷td1) (t0z2÷toz1g), depends on a ratio of atmospheric transmittance for such two channels, including ozone and diffuse transmittance. As a simple but efficient algorithm of gradient, the algorithm of αR1 R 2 is selected to retrieve gradient α and then sea surface suspendend sediment concentration.  相似文献   

4.
The effect of Mach number on transonic flow past a circular cylinder is investigated numerically for the free-stream Mach number M∞ from 0.85 to 0.98 and the Reynolds number 2×10^5 based on the diameter of the cylinder. The work provides an insight into several salient features, including unsteady and quasi-steady flow state, formation of local supersonic zone, and evolution of turbulent shear layer. Results show that there exist two flow states dependent of a critical Mach number Mcr around 0.9. One is an unsteady flow state characterized by moving shock waves interacting with the turbulent flow in the near region of the cylinder for M∞〈Mcr, and the other is a quasi-steady flow state with nearly stationary shock waves formed in the near wake for M∞〉Mcrs, suppressing vortex shedding from the cylin- der. Some flow behaviors in the unsteady and quasi-steady flow states are revealed. From time evolu- tion of flow structures, local supersonic zones are identified in the wake and generated by two typical processes, i.e. reverse flow behind the cylinder and shed vortices in the near wake. The convective Mach number Mc of turbulent shear layers shed from the cylinder is identified nearly as Mc〈I in the unsteady flow regime and Mc〉I in the quasi-steady flow regime, resulting in different evolutions of the shear layers.  相似文献   

5.
Suppose that P=(p\-1, p\-2, ..., p\-M)\% is a probability vector with p\-i>0 and Y={1, 2, ..., M}. Let (Y, 2\+Y, μ) be a probability space with μ(i)=p\-i, i=1, 2, ..., M, and (∑\-M, B, m)= Π \+∞\-0(Y, 2\+U, μ). It is shown that for any a \%(0≤a ≤1) \%, there exists a set U∈B such that m(U)=a and the Julia set associated with U is equal to the Julia set associated with ∑\-M\%. Moreover repelling fixed points with respect to U are dense in the Julia set associated with U.  相似文献   

6.
We study the spaces Hp, Sp, Kp, ∑p and ,p of martingales with measure du=ψdυ,where ψ is a function with Clifford algebra values and satisfies bp+-condition. We proved they are equivalent and isomorphic to the corresponding spaces of martingales with real measure dυ, respectively(1≤p<∞). In the end,we give a martingale f such that f=(fn) ∞∈1K∞ but f=(E(ψ| n)fn)n≥ ∈1K∞.  相似文献   

7.
8.
Based on the prerequisite that the earliest acid rock formed because of the initial global expanding tectonic processes, by combining it with other geological limitation conditions, and starting from the lithosphere elastic mechanics, the following is defined: the earth expansion started at about 4300 Ma ago, the average increasing rate of the earth radius is 0.40 mm/a, the initial expanding earth radius is 4651 km, and the initial global expansion of tectonic processes happened at 4183.7 Ma ago. From the natural and attenuation evolution condition of the earth and terrestrial planets, through the limit condition got from the combination of the mathematics logic and the geological significance, the limited expanding earth evolution model is established as follows: in whichR 0= 4.651×106 m,A =1.86×106 m, β = -6.01×10−10/ a andt s=3×108 a. From this model the maximum radiusR maxof the limited expanding earth evolution should be 6511 km. The earth’s radius increasing rate is about 0.1 mm/a at present.  相似文献   

9.
Some weak asymptotic results for average σ-K width and average σ_L width of the isotropic Besov classes S r pθB(R d), S r pθb(R d) and the anisotropic Besov classes S r pθB(R d), S r pθb(R d) in L p(R d) (1≤p<∞) are obtained, and the corresponding weak asymptotic optimal subspaces are identified. Furthermore, the weak asymptotic behavior of optimal recovery is established for the isotropic Besov classes S r pθB(R d) in L p(R d) (1≤p≤∞).  相似文献   

10.
The kinetic parameters of hydrocarbon generation from the marine carbonate source rocks were determined and calibrated through kinetic simulating experiment. The kinetic parameters of hydrocarbon generation then were extrapolated to geological condition by using the relative software. The result shows that gaseous hydrocarbons (C_1, C_2, C_3, C_(4-5)) were generated in condition of 150℃相似文献   

11.
It is dealt with positive solutions to the systems: u-t-u- XX =v+p, v-t-v XX =u+q in Ω×(0, T) subject to either initial conditions or boundary_value conditions. The exact blowup rate estimates of solution are established under some monotonicity assumptions on the initial values.  相似文献   

12.
We discussed the Dirichlet problem of semilinear elliptic equationin (Pβ,α)D;-β△u=uε+εu,u>0,in Ω u=0, on(e),Ω where Ω(∪)RN(N≥4) is smooth and bounded domain,P=N+2/N-2,β,ε>0. We have proved that there exist positive ε0 and ε1 , such that when 0≤ε≤ε0,β>√ε1,(P0,1)has a single-peaked solution uβ, furthermore, |▽μβ|-0in the sense of measure as ε→0 and β→0.  相似文献   

13.
Orientational domains at room temperature in orthorhombic perovskite La0.33Ca0.67MnO3 were studied by group-theory and observed systematically using transmission electron microscopy. There are six orientational variants (A, A′, B, B′, C andC′) in orthorhombic perovskite La0.33Ca0.67MnO3. Their orthorhombicb o directions are parallel to thea p,b p andc p directions of the cubic prototypic perovskite, respectively. In each case there are two orientational variants (e.g.,A andA′) with theira o andc o axes interchanged. Among the possible 15 boundaries between these 6 variants there are only two types of domain boundaries: (1) m<100>boundariesC′/C, A′/A, andB′/B. (2) m<110>boundaryiesC′/A, C′/A′, C′/B, C′/B′, C/A, C/A′, C/B, C/B′, B′/A, B′/A′, B/A, andB/A′. Foundation item: Supported by the National Natural Science Foundation of China (19974031) and US DOE(DE-AC02-98CH10886) Biography: WANG Ren-hui (1937-), male, Professor.  相似文献   

14.
Molecular devices are the ultimate goal in the miniaturization of the electronic technology. Based on the unique properties of DNA (e.g. self-assembly and molecular recognition), people have made great efforts to develop molecular devices in the last few …  相似文献   

15.
The current study was to investigate mRNA expression of cyclin D2 and p16 during the transition from cardiac myocyte hyperplasia to hypertrophy. Cultured cardiac myocytes (CM) and fibroblasts (FC) obtained from 1-day-old Sparague-Dawley rats were used in this study. We have determined (1) hyperplasia by cell growth curve and fluorescence activated cell sorting (FACS); and (2) ultrastructure by electron microscope observation; and (3) expresions of cyclin D2 mRNA and p16 mRNA by using in situ hybridization and image analysis. The results were shown (1) Results of cell growth curve and FACS analysis showed CM could proliferate in the first 3 cultured days (4 days in postnatal development). But the ability decreased quickly, concomitant with the differentiation. (2) The ultrastructure of CM showed the large amount of myofilaments and mitochondrion and FC showed moderate amount of rough endoplasmic reticulum. (3) The expression of cyclin D2 mRNA in 3−, 4−, 5−day CM group was 0.89 times (p<0.05), 0.80 times (p<0.05) and 0.56 times (p<0.01) of that in 1-day group respectively. P16 mRNA in 2−, 3−, 4−, 5−day CM group were 1.63 times (p<0.01), 1.72 times (p<0.01), 1.99 times (p<0.01) and 2.84 times (p<0.01) of that in 1−day group respectively. It can be concluded that cultured neonatal rat cardiac myocytes could proliferate during the first 3 cultured days, but the ability of proliferation decreased, from the fourth day, concomitant with differentiation. Cyclin D2 and p16 have the key roles during the transition from myocyte hyperplasia to hypertrophy. Biography: Zhang Yu-xia (1974-), female, Master, research direction: cardiovascular pathology.  相似文献   

16.
0 IntroductionInrecentyears,studiesonBinghamfluid ,suchasElec trorheologicalfluid ,areactivelypursued[1 6] .Rheologicaltechniqueshavebeenplayinganimportantroleinsyntheticchem istry .Therheologicalphasereactionmethodisthe processofpreparingcompoundsormaterialsfromasolid liquidrheologicalmixture.Thatis,thesolidreactantsarefullymixedinapropermolarratio ,andmadeupbyaproperamountofwaterorothersolventstoaBinghambodyinwhichthesolidparticlesandliquidsubstanceareuniformlydistributed ,sothattheprodu…  相似文献   

17.
Nanometer ferromagnetic metal-semiconductor matrix Fe−In2O3 granular films are fabricated by the radio frequency sputtering. Magnetic properties and the giant magnetoresistance (GMR) effect of Fex(In2O3)1−x granular film samples are studied. The result shows that the magnetoresistance (MR) ratio Δρ/ρ 0 value of the granular film samples with Fe volume fraction x=35% is 4.5% at room temperature. The temperature dependence (T=1.5–300 K) of the MR ratio Δρ/ρ 0 value of Fe0.35(In2O3)0.65 granular films shows that Δρ/ρ 0 value below 10 K increases rapidly with the decrease of the temperature, and when T=2 K, Δρ/ρ 0 value is 85%. Through the study of the dependence of low field susceptibility on temperature and the hysteresis loops at different temperatures, it has been found that, when the temperature decreases to a critical point T p=10 K, the change of the structure in Fe0.35)In2O3)0.65 granular films results in the transformation of state from ferromagnetic to spin-glass-like. The remarkable increase of the MR ratio Δρ/ρ 0 value of Fe0.35(In2O3)0.65 granular films below 10 K seems to arise from the peculiar conducting mechanism of the granular film samples in the spin-glass-like state.  相似文献   

18.
The compressional sound velocity Vp for enstatite of polycrystalline specimens were measured at pressures from 40 to 140 GPa using the optical analytical techniques under shock loading. The dependence of VP, (in km/s) on Hugoniot pressure (P, in GPa) can be described by InVp= 3.079-0.691 In(P) + 0.094(lnP)2. Vp satisfies Birch’s law:V p = 4.068 + 1.677ρ, where ρ is corresponding density, which indicated that enstatite is stable throughout the conditions of the lower mantle. The wave velocityP is 0.5% lower and the wave velocity S is 2% higher than that of PREM respectively. We concluded that the lower mantle is mainly composed of perovskite-(Mg1-x, Fex) SiO3 and only a small amount of (Mg1-x, Fex) O is allowed in it.  相似文献   

19.
In this paper, we prove an extrapolation theorem of operators in martingale spaces with A p weights, which shows that for operators T defined on martingale space L u 1 , if T is bounded on martingale space L p0(w) for some 1 < p 0 < ∞ and every, wA , so it is on L p,s (w) for every 1 < p, s < ∞, and wA . We also get some properties of A p weights and prove that if wA 1, then the maximal operator M is bounded on L p,q (w) with 1 < p < ∞, 1 < q ≤ ∞.  相似文献   

20.
Song  Jirong  Chen  Zhaoxu  Xiao  Heming  Hu  Rongzu  Li  Fuping 《科学通报(英文版)》1999,44(3):214-218
[Li(NTO)(H2O)2] was prepared by mixing the aqueous solution of 3-nitro-1,2,4-triazol-5-one (NTO) and lithium hydroxide. The crystal structure of [Li(NTO)(H2O)2] was determined by single crystal diffraction analysis. The crystal is monoclinic, space group P21/n with crystal parameters of a = 0.742 0(2) nm, b = 0.344 9(1) nm,c = 2.490 6(3) nm, β= 94.89(1)°, Z = 4,D c , = 1.799 g cm−3,V = 0.635 nm3, μ = 1.591 cm−1, F(000) = 392. The finalR is 0.051. The MNDO MO calculation shows that the coordinate bonds of title compound possess certain extent of covalent character. O2 atom of NTO anion is bonded to Li atom; the nitro group will be lost first when NTO is decomposed.  相似文献   

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