Low-complexity PTS scheme based on phase factor sequences optimization

In this paper, a new partial transmit sequence（PTS）scheme with low computational complexity is proposed for the problems of high computational complexity in the conventional PTS method. By analyzing the relationship of candidate sequences in the PTS method under the interleaved partition method, it has been discovered that some candidate sequences generated by phase factor sequences have the same peak average power ratio（PAPR）. Hence, phase factor sequences can be optimized to reduce their searching times. Then, the computational process of generating candidate sequences can be simplified by improving the utilization of data and minimizing the calculations of complex multiplication. The performance analysis shows that, compared with the conventional PTS scheme, the proposed approach significantly decreases the computational complexity and has no loss of PAPR performance.

Theoretical investigation on the dendritic cells algorithm

The aims of this paper are to helpunderstand the dendritic cells algorithm （DCA） and re- duce the potential incorrect applications and implementations, to clearly present the formal descrip- tion of the dendritic cells algorithm, and to theoretically deduce the algorithm＇ s runtime complexity and detection performance. The entire dendritic cells population of the algorithm is specified using quantitative measures at the functional level. Basic set theory and computational functions, such as addition, multiplication and recursion, are used for clarity and definition, and theoretical analysis is implemented via introduction of three runtime variables in terms of three phases of the algorithm. Consequently, the data structures, procedural operations and pseudocode description of the dendrit- ic cells algorithm are given. The standard DCA achieves a lower bound of ^（n） runtime complexity and an upper bound of O（ n2） runtime complexity under the worst case. In addition, the algorithm＇ s runtime complexity can be improved to O （max（ nN, nS）） by utilizing segmentation approach, where n is the number of input instances, N is the population size and 8 is the size of each segment.

A new complex variable meshless method for transient heat conduction problems

In this paper, based on the improved complex variable moving least-square （ICVMLS） approximation, a new complex variable meshless method （CVMM） for two-dimensional （2D） transient heat conduction problems is presented. The variational method is employed to obtain the discrete equations, and the essential boundary conditions are imposed by the penalty method. As the transient heat conduction problems are related to time, the Crank-Nicolson difference scheme for two-point boundary value problems is selected for the time discretization. Then the corresponding formulae of the CVMM for 2D heat conduction problems are obtained. In order to demonstrate the applicability of the proposed method, numerical examples are given to show the high convergence rate, good accuracy, and high efficiency of the CVMM presented in this paper.

Zero-field splitting parameters and local structures for tetragonal Cr^(2+) centers in Cr^(2+)-doped ZnSe semiconductors

The inter-relation between zero-field splitting （ZFS） parameters and local lattice structures of the （CrSe4）6 clusters in ZnSe semiconductors has been established by using the complete diagonalization （of the energy matrix） method. On the basis of this, the local lattice distortions, the ZFS parameters D, a, F and the optical spectrum for Cr2＋ ions doped into ZnSe are theoretically investigated, and the contributions of the spin singlets have been taken into account. The calculated ZFS parameters are in good agreement with the experimental values. From our calculations, the tetragonal distortion parameters AR = 0.091A and Aθ = 4.28° of Cr2＋ in ZnSe are acquired, and the results suggest that there exists a tetragonal expansion distortion for the local lattice structure of （CrSe4）6- clusters in ZnSe crystals. The influence of the spin singlets on ZFS parameters is also discussed, indicating that the contributions to ZFS parameters a and F cannot be ignored.