该文描述带有矩量序列{v_m}_0~∞■C^(q×q)的完全不确定Hamburger矩阵矩量问题:v_m=integral from n=-∞to∞x^m dρ(x),m=0,1,…的有限阶解,即该问题的那些解ρ,使得C^(q×q)-值多项式的线性空间P在对应的空间L^2(R,dρ/E(x)...该文描述带有矩量序列{v_m}_0~∞■C^(q×q)的完全不确定Hamburger矩阵矩量问题:v_m=integral from n=-∞to∞x^m dρ(x),m=0,1,…的有限阶解,即该问题的那些解ρ,使得C^(q×q)-值多项式的线性空间P在对应的空间L^2(R,dρ/E(x))内稠密,这里E(x)为在实轴R上取正值的某个数值多项式.作为预备知识,作者考虑所谓广义Akhiezer插值的矩阵变种与它的相关矩阵矩量问题之间的一种关系.展开更多
A class of matrix inverse problems minimizing ‖A-‖ F on the linear manifold l A={A∈R n×m |‖AX-B‖ F=min} is considered. The perturbation analysis of the solution to these problems is carried out. Th...A class of matrix inverse problems minimizing ‖A-‖ F on the linear manifold l A={A∈R n×m |‖AX-B‖ F=min} is considered. The perturbation analysis of the solution to these problems is carried out. The perturbation upper bounds of the solution are given for both the consistent and inconsistent cases. The obtained preturbation upper bounds are with respect to the distance from the perturbed solution to the unperturbed manifold.展开更多
The relay node with linear relaying transmits the linear combination of its past received signals.The optimization of two-hop relay channel with linear relaying is discussed in this paper.The capacity for the two-hop ...The relay node with linear relaying transmits the linear combination of its past received signals.The optimization of two-hop relay channel with linear relaying is discussed in this paper.The capacity for the two-hop Gaussian relay channel with linear relaying is derived,which can be formulated as an optimization problem over the relaying matrix and the covariance matrix of the signals transmitted at the source.It is proved that the solution to this optimization problem is equivalent to a "single-letter" optimization problem.We also show that the solution to this "single-letter" optimization problem has the same form as the expression of the rate achieved by Time-Sharing Amplify and Forward(TSAF).In order to solve this equivalent problem,we proposed an iterative algorithm.Simulation results show that if channel gain of one hop is relatively smaller,the achievable rate with TSAF is closer to the max-flow min-cut capacity bound,but at a lower complexity.展开更多
There are a lot of security issues in block cipher algorithm.Security analysis and enhanced design of a dynamic block cipher was proposed.Firstly,the safety of ciphertext was enhanced based on confusion substitution o...There are a lot of security issues in block cipher algorithm.Security analysis and enhanced design of a dynamic block cipher was proposed.Firstly,the safety of ciphertext was enhanced based on confusion substitution of S-box,thus disordering the internal structure of data blocks by four steps of matrix transformation.Then,the diffusivity of ciphertext was obtained by cyclic displacement of bytes using column ambiguity function.The dynamic key was finally generated by using LFSR,which improved the stochastic characters of secret key in each of round of iteration.The safety performance of proposed algorithm was analyzed by simulation test.The results showed the proposed algorithm has a little effect on the speed of encryption and decryption while enhancing the security.Meanwhile,the proposed algorithm has highly scalability,the dimension of S-box and the number of register can be dynamically extended according to the security requirement.展开更多
A traffic matrix is a necessary parameter fornetwork management functions,and itsupplies a flow-level view of a largescale IP-over-WDM backbone network.This paper studies the problem of traffic matrix estimationand pr...A traffic matrix is a necessary parameter fornetwork management functions,and itsupplies a flow-level view of a largescale IP-over-WDM backbone network.This paper studies the problem of traffic matrix estimationand proposes an exact traffic matrix estimation approach based on network tomography techniques.The traditional network tomography model is extended to make it compatible with compressive sensing constraints.First,a stochastic perturbation is introduced in the traditional network tomography inference model.Then,an algorithm is proposed to achieve additional optical link observations via optical bypass techniques.The obtained optical link observations are used as extensions for the perturbed network tomography model to ensure that the synthetic model can meetcompressive sensing constraints.Finally,the traffic matrix is estimated from the synthetic model by means of a compressive sensing recovery algorithm.展开更多
文摘该文描述带有矩量序列{v_m}_0~∞■C^(q×q)的完全不确定Hamburger矩阵矩量问题:v_m=integral from n=-∞to∞x^m dρ(x),m=0,1,…的有限阶解,即该问题的那些解ρ,使得C^(q×q)-值多项式的线性空间P在对应的空间L^2(R,dρ/E(x))内稠密,这里E(x)为在实轴R上取正值的某个数值多项式.作为预备知识,作者考虑所谓广义Akhiezer插值的矩阵变种与它的相关矩阵矩量问题之间的一种关系.
文摘A class of matrix inverse problems minimizing ‖A-‖ F on the linear manifold l A={A∈R n×m |‖AX-B‖ F=min} is considered. The perturbation analysis of the solution to these problems is carried out. The perturbation upper bounds of the solution are given for both the consistent and inconsistent cases. The obtained preturbation upper bounds are with respect to the distance from the perturbed solution to the unperturbed manifold.
基金supported by the National Natural Science Foundation of China under Grants No.60972045,No.61071089the Natural Science Foundation of Jiangsu Province under Grant No. BK2010077+4 种基金the Open Project of State Key Laboratory of Networking and Switching under Grant No.SKLNST-2009-1-12the Priority Academic Program Development of Jiangsu Provincethe University Postgraduate Research and Innovation Project in Jiangsu Province under Grant No.CXZZ11_0395the Fundamental Research Funds for the Central Universities under Grant No.2009B32114the Excellent Innovative Research Team of High Schools in Jiangsu Province under Grant No.TJ208029
文摘The relay node with linear relaying transmits the linear combination of its past received signals.The optimization of two-hop relay channel with linear relaying is discussed in this paper.The capacity for the two-hop Gaussian relay channel with linear relaying is derived,which can be formulated as an optimization problem over the relaying matrix and the covariance matrix of the signals transmitted at the source.It is proved that the solution to this optimization problem is equivalent to a "single-letter" optimization problem.We also show that the solution to this "single-letter" optimization problem has the same form as the expression of the rate achieved by Time-Sharing Amplify and Forward(TSAF).In order to solve this equivalent problem,we proposed an iterative algorithm.Simulation results show that if channel gain of one hop is relatively smaller,the achievable rate with TSAF is closer to the max-flow min-cut capacity bound,but at a lower complexity.
基金supported in part by National Natural Science Fundation of China under Grant No.61202458,61403109
文摘There are a lot of security issues in block cipher algorithm.Security analysis and enhanced design of a dynamic block cipher was proposed.Firstly,the safety of ciphertext was enhanced based on confusion substitution of S-box,thus disordering the internal structure of data blocks by four steps of matrix transformation.Then,the diffusivity of ciphertext was obtained by cyclic displacement of bytes using column ambiguity function.The dynamic key was finally generated by using LFSR,which improved the stochastic characters of secret key in each of round of iteration.The safety performance of proposed algorithm was analyzed by simulation test.The results showed the proposed algorithm has a little effect on the speed of encryption and decryption while enhancing the security.Meanwhile,the proposed algorithm has highly scalability,the dimension of S-box and the number of register can be dynamically extended according to the security requirement.
基金supported in part by the National Natural Science Foundation of China(Nos.61571104,61071124,61501105)the General Project of Scientific Research of the Education Department of Liaoning Province(No.L20150174)+2 种基金the Program for New Century Excellent Talents in University(No.NCET-11-0075)the Fundamental Research Funds for the Central Universities(Nos.N150402003,N120804004,N130504003,N150404018)the State Scholarship Fund(201208210013)
文摘A traffic matrix is a necessary parameter fornetwork management functions,and itsupplies a flow-level view of a largescale IP-over-WDM backbone network.This paper studies the problem of traffic matrix estimationand proposes an exact traffic matrix estimation approach based on network tomography techniques.The traditional network tomography model is extended to make it compatible with compressive sensing constraints.First,a stochastic perturbation is introduced in the traditional network tomography inference model.Then,an algorithm is proposed to achieve additional optical link observations via optical bypass techniques.The obtained optical link observations are used as extensions for the perturbed network tomography model to ensure that the synthetic model can meetcompressive sensing constraints.Finally,the traffic matrix is estimated from the synthetic model by means of a compressive sensing recovery algorithm.