Moment-Based Method to Estimate Image Affine Transform

The estimation of affine transform is a crucial problem in the image recognition field. This paper resorted to some invariant properties under translation, rotation and scaling, and proposed a simple method to estimate the affine transform kernel of the two-dimensional gray image. Maps, applying to the original, produce some correlative points that can accurately reflect the affine transform feature of the image. Furthermore, unknown variables existing in the kernel of the transform are calculated. The whole scheme only refers to one-order moment, therefore, it has very good stability.

Joint DOA and polarization estimation for unequal power sources based on reconstructed noise subspace

In most literature about joint direction of arrival（DOA） and polarization estimation, the case that sources possess different power levels is seldom discussed. However, this case exists widely in practical applications, especially in passive radar systems. In this paper, we propose a joint DOA and polarization estimation method for unequal power sources based on the reconstructed noise subspace. The invariance property of noise subspace（IPNS） to power of sources has been proved an effective method to estimate DOA of unequal power sources. We develop the IPNS method for joint DOA and polarization estimation based on a dual polarized array. Moreover, we propose an improved IPNS method based on the reconstructed noise subspace, which has higher resolution probability than the IPNS method. It is theoretically proved that the IPNS to power of sources is still valid when the eigenvalues of the noise subspace are changed artificially. Simulation results show that the resolution probability of the proposed method is enhanced compared with the methods based on the IPNS and the polarimetric multiple signal classification（MUSIC） method. Meanwhile, the proposed method has approximately the same estimation accuracy as the IPNS method for the weak source.

On Lie symmetries and invariant solutions of Broer-Kaup-Kupershmidt equation in shallow water of uniform depth

The dynamics of atmosphere and ocean can be examined under different circumstances of shallow water waves like shallow water gravity waves,Kelvin waves,Rossby waves and inertio-gravity waves.The influences of these waves describe the climate change adaptation on marine environment and planet.Therefore,the present work aims to derive symmetry reductions of Broer-Kaup-Kupershmidt equation in shallow water of uniform depth and then a variety of exact solutions are constructed.It represents the propagation of nonlinear and dispersive long gravity waves in two horizontal directions in shallow water.The invariance of test equations under one parameter transformation leads to reduction of independent variable.Therefore,twice implementations of symmetry method result into equivalent system of ordinary differential equations.Eventually,the exact solutions of these ODEs are computed under parametric constraints.The derive results entail several arbitrary constants and functions,which make the findings more admirable.Based on the appropriate choice of existing parameters,these solutions are supplemented numerically and show parabolic nature,intensive and non-intensive behavior of solitons.

Symmetry and nonexistence of positive solutions to an integral system with weighted functions

Consider the system of integral equations with weighted functions in Rn,{u(x) =∫Rn|x-y|α-nQ(y)v(y)qdy1,v(x)=∫Rn|x-y|α-nK(y)u(y)pdy,where 0 < α < n,1/(p+1) + 1/(q+1)≥(n-α)/n1,α/(n-α) < p1q < ∞1,Q(x) and K(x) satisfy some suitable conditions.It is shown that every positive regular solution(u(x)1,v(x)) is symmetric about some plane by developing the moving plane method in an integral form.Moreover,regularity of the solution is studied.Finally,the nonexistence of positive solutions to the system in the case 0 < p1q <(n+α)/(n-α) is also discussed.

Low-complexity 2D coherently distributed sources decoupled DOAs estimation method

The existing directions-of-arrival （DOAs） estimation methods for two-dimensional （2D） coherently distributed sources need one- or two-dimensional search, and the computational complexities of them are high. In addition, most of them are designed for special angular signal distribution functions. As a result, their performances will degenerate when deal with different sources with different angular signal distribution functions or unknown angular signal distribution functions. In this paper, a low-complexity decoupled DOAs estimation method without searching using two parallel uniform linear arrays （ULAs） is proposed for coherently distributed sources, as well as a novel parameter matching method. It can resolve the problems mentioned above efficiently. Simulation results validate the effectiveness of our approach.

Queue reduction in discrete-event systems by relabeling

The customer population of entities potentially requesting to join a queue for service often have identical structure, i.e., the same state set and isomorphic transitions. The state size of the automaton modeling a queue will grow rapidly with increase of the size of this population. However, by relabeling the queue arrival events and service events to the same symbols respectively, the automaton model of a queue will be converted to the structure of a buffer, which is proved to be independent of the total size of the customer population, as long as the queue size is held fixed. We propose the model of a dynamic buffer to embody order and shift of a queue. The result is applied to a manufacturing facility with a dynamic buffer to manage the repair of broken down machines.

Analysis and Invariant Properties of a Lattice Boltzmann Method

We investigate a two-relaxation-time(TRT)lattice Boltzmann algorithm with the asymptotic analysis technique.The results are used to analyze invariance properties of the method.In particular,we focus on time dependent Stokes and Navier-Stokes problems.