共查询到20条相似文献，搜索用时 156 毫秒
1.
By bilinear approach we derive N-soliton-like solutions for a variable coefficient KdV equation with some x-dependent coefficients. This equation can be considered as a non-isospectral variable coefficient KdV equation. Solutions in Hirota’s form and Wronskian form are given, respectively. 相似文献
2.
毕金钵 《上海大学学报(英文版)》2004,8(3):286-288
AA modified version of the bilinear Baecklund transformation for the MKdV equation was given, with which some new solutions of the MKdV equation are obtained. The approach used here is general and can be applied to other soliton equations. 相似文献
3.
In this paper, the Toda equation and the discrete nonlinear Schrdinger equation with a saturable nonlinearity via the discrete ＂ （G′/G＂）-expansion method are researched. As a result, with the aid of the symbolic computation, new hyperbolic function solution and trigonometric function solution with parameters of the Toda equation are obtained. At the same time, new envelop hyperbolic function solution and envelop trigonometric function solution with parameters of the discrete nonlinear Schro¨dinger equation with a saturable nonlinearity are obtained. This method can be applied to other nonlinear differential-difference equations in mathematical physics. 相似文献
4.
HUXiaohong ZHANGXingyou 《重庆大学学报(英文版)》2004,3(1):89-91
The existences of the global attractor A^ε for a degenerate parabolic equation and of the homogenized attractor A^0 forthe corresponding homogenized equation are studied, and explicit estimates for the distance between A^ε and A^0 are given. 相似文献
5.
HUANGDe－bin LIUZeng－rong 《上海大学学报(英文版)》2001,5(4):273-275
In this paper,the nonlinear Schrodinger(NLS)equation was analytically solved.Firstly,the stationary solutions of NLS equation were explicitly given by the elliptic functions.Then a family of exact solutions of NLS equation were botained from these stationary solutions by a method for finding new exact solutions from the stationary solutions of integrable evolution equations. 相似文献
6.
张大军 《上海大学学报(英文版)》2005,9(3):206-209
An infinite number of semi-discrete and continuous conservation laws for the differential-difference KP equation were obtained by using a solvable generalized Riccati equation. 相似文献
7.
张大军 《上海大学学报(英文版)》2004,8(1):4-7
N-soliton solutions in the Wronskian form for the KdV equation with loss and nonuniformity terms were obtained. New rational-like solutions and mixed solutions were further derived. All these solutions were verified by direct substitutions into bilinear equation. 相似文献
8.
The mixed AKNS nonlinear evolution equation in equation, which contains an isospectral term the AKNS system. So searching for its exact and a nonisospectral term, is an important solutions is vital both for the AKNS system and in mathematical sense. In this paper, the corresponding Lax pair was given, the bilinear forms of the mixed AKNS equation were obtained through introducing the transformation of dependent variables. By using Hirota＇s bilinear method, the N-soliton solutions were obtained. 相似文献
9.
One-dimensional traffic model was studied with the consideration of stochastic deceleration by using the lattice Boltzmannmethod.The evolution equation for vehicle density was derived,which has the form of the Burgers equation exhibiting the effect of viscosity corresponding to the deceleration.The simulation with the model shows that the variation of vehicle density in space tends to a periodic one,which implies the existence of kinematic waves in the 1D traffic flow and coincides with theoretical prediction. 相似文献
10.
11.
Abstract A new function-valued partial Padé-type approximation was introduced in the polynomial space, and an explicit determinant formula was derived by means of some orthogonal polynomials. This method can be applied to estimating surplus eigenvalues of the Fredholm integral equation of the second kind when its partial eigenvalues have been known, and at the same time, it can be applied to solving the approximating solution of the given equation. 相似文献
12.
In an effort to find the effect of mass transfer ,surface tesion and drag forces on the velocity distribution,the mathematical model of the velocity profile of a nascent hollow fiber during membrane formation in the air gap region was numerically simulated by using the Runge-Kutta method (fourth-order method).The effect of mass transfer on velocity distribution based on the complicated function(G(Ch^s))was presented and the dffects of a complicated function were studied in two cases:in the first case,G(Ch^s) was constant;in the second,G(Ch^s) was variable.The latter was done by varying with the concentration of solvent in a nascent hollow fiber through the air-gap region.One empirical equation was used to describe this change and the predected values had a better agreement with the experimental values.To verify the moedl hypotheses,hollow fiber membranes were spun from 20:80 polybenzimidazole/polyetherimide dopes with 25.6 wt％ solid in N,N-dimethylacetamide (DMAc) using water as the external and internal coagulants.Based on the experimental results of dry-jet wet-spinning process for the fabrication of hollow fiber membranes,it is found that the model calculated values were in a good agreement with the experimental values. 相似文献
13.
In this paper, we prove that any polygon P in R2 containing a fixed smooth. strictly convex and origin-symmetric body Γ whose boundary is real analytic in its interior, can be determined by its Γ-section functions among the polygons. 相似文献
14.
Exchange coupling and magnetization reversal mechanism in two series of Co_xNi_(1-x)/CoO(30 nm)(x=0.2 and 0.4)bilayers are studied by vector magnetometer.Two components of magnetization are measured parallel and perpendicular to the applied field.At low temperatures,coercivity H_c∝(t_(FM))~(-n),n=1.5 and 1.38 for x=0.2 and 0.4,respectively,in agreement with the random field model.At room temperature,the coercivity is nearly proportional to the inverse FM layer thickness.In addition to the exchange field and the coercivity,the characteristic of the magnetization reversal mechanism was found to change with temperature.At temperatures below 180 K,magnetization reversal process along the unidirectional axis is accompanied only by nucleation and pinning of domain wall while magnetization rotation is also involved at high temperatures. 相似文献
15.
In the light of Ф-mapping method and the relationship between entropy and the Euler characteristic, the intrinsic topological structure of entropy of Kerr black holes is studied. From the Ganss-Bonnet-Chem theorem, it is shown that the entropy of Kerr black hole is determined by singularities of the Killing vector field of spacetime. These singularities naturally carry topological numbers, Hopf indices and Brouwer degrees, which can also be viewed as topological quantization of entropy of Kerr black holes. Specific results S = A/4 for non-extreme Kerr black holes and S = 0 for extreme ones are calculated independently by using the above-mentioned methods. 相似文献
16.
The Bacillus firmus was immobilized into Ca-alginate beads according to the different initial biomass concentration, calcification time and activation time.Three types of immobilized Bacillus firmus beads were packed respectively in trickling biofilter to purify xylene contained waste gases,and the performance of immobilized-cell biofilter was compared with traditional biofilm attached biofilter packed with two types of ceramic pellets.The results showed that three types of immobilized beads had different capabilities for removing xylene and life-spans.Higher initial biomass in immobilized beads resulted in better performance but shorter life-span.Activation process can remarkably enhance the activity of bacteria,and the removal efficiency of xylene can substantially be improved.Calcification time had influence on life-span of immobilized beads.Without acclimation,the cell-entrapped biofilter can obtain the maximum elimination capacity of 92.4 g/(m~3·h).However,compared with biofilm attached biofilter,it has a poorer intrinsic drawback in volatile organic compounds (VOCs) removal due to the existence of excess mass transfer resistance. 相似文献
17.
关于混沌洛伦兹系统和陈系统中的广义投影同步 总被引：1，自引：1，他引：1
1 Introduction Since Pecora and Carroll[1]showed that it is possibleto synchronize two identical chaotic systems , chaossynchronization has been intensively and extensivelystudied due to its potential applications in secure com-munication,ecological systems ,systemidentification,etc.(see [2] and a huge volume of references citedtherein) . Among all kinds of chaos synchronizations ,projec-tive synchronization is one of the most noticeableones .This kind of synchronization was first observedin … 相似文献
18.
A rice mutant with Yaponica 9522 cultivar background Oryza sativa extraordinary glume 1 （Oseg 1） was identified from the M2 mutant pool mutagenized by ^60Co γ-ray. Compared with wild type plants, Oseg 1 developed longer empty glumes and rudimentary glumes. In some Oseg 1 mutants, the number of stamens of flowers was reduced and leaf-like lodicules occurred, and excessive lemma/palea-like organ could be observed in some mutant spikelets. This indicated that OsEG1 could regulate the development of rudimentary glumes, empty glumes, lemma/palea, lodicules, and stamens. Genetic analysis indicated that Oseg 1 came from a single recessive genetic locus. To clone OsEG1 gene, F2 population was constructed by a cross between Oseg 1 （Japonica） and Guangluai4 （Indica）. Using map-based cloning approach, OsEG1 was mapped on chromosome 4, between INDEL marker OS407 and WHM0466 with genetic distance of 2.0 cm and 1.0 cm, respectively. These results are useful for further cloning and functional analysis of the OsEG1 gene. 相似文献
19.
Xia A-gen Ye Jian-ting Ye Quan-lin Tao Xiang-ming Jin Jin-sheng Ye Gao-xiang 《浙江大学学报(A卷英文版)》2001,2(4):379-383
A new aluminum thin film percolation system, deposited on glass and silicon wafer surfaces by a vapor deposition method, was
investigated. By using the expansive and mobile behaviors of the silicone oil, the Al films are quenched gradually by the
silicone oil during the deposition process. TheR-I behavior of the film system was studied, and the anomalous conductivity indicated that, at very low current, the hopping
and tunneling effects in the films are much stronger than those of the normal film systems.
Project supported by NSFC (Grant No. 19874016) and the Special Fund of Zhejiang Provincial Natural Science Foundation for
Young Scientists (Grant No. 1997-RC9603). 相似文献
20.
Stabilization for a class of second-order switched systems with saturation constrains 总被引：1，自引：0，他引：1
This paper proposes a global stabilization method for a class of planar switched systems with input saturation constrains
by using a state feedback and switching strategy. This method is proved to be effective by analyzing the characteristics of
the trajectory of second-order linear systems with input saturation.
Project supported by the China Postdoctoral Science Foundation (Grant No.20070420643), the National Natural Science Foundation
of China (Grant No.60774059), and the Innovation Program of the Shanghai Municipal Science and Technology Commission (Grant
No.08DZ2272400) 相似文献