This paper mainly studies the optimal investment problem of defined contribution(DC)pension under the self-protection and minimum security.First,we apply Ito?theorem to obtain the differential equation of the real sto...This paper mainly studies the optimal investment problem of defined contribution(DC)pension under the self-protection and minimum security.First,we apply Ito?theorem to obtain the differential equation of the real stock price after discounting inflation.Then,under the constraint of external guarantee of DC pension terminal wealth,self-protection is introduced to study the maximization of the expected utility of terminal wealth at retirement time and any time before retirement.The explicit solution of the optimal investment strategy of DC pension at retirement time and any time before retirement should be derived by martingale method.Finally,the influence of selfprotection on the optimal investment strategy of DC pension is numerically analyzed.展开更多
Distributed Denial of Service(DDoS) attacks have been one of the most destructive threats to Internet security. By decoupling the network control and data plane, software defined networking(SDN) offers a flexible netw...Distributed Denial of Service(DDoS) attacks have been one of the most destructive threats to Internet security. By decoupling the network control and data plane, software defined networking(SDN) offers a flexible network management paradigm to solve DDoS attack in traditional networks. However, the centralized nature of SDN is also a potential vulnerability for DDo S attack. In this paper, we first provide some SDN-supported mechanisms against DDoS attack in traditional networks. A systematic review of various SDN-self DDo S threats are then presented as well as the existing literatures on quickly DDoS detection and defense in SDN. Finally, some promising research directions in this field are introduced.展开更多
According to the data from IFSL(International Financial Services, London), Pension funds increased rapidly in recent year. Pension funds always have different ways to build up. One form always from the institutional i...According to the data from IFSL(International Financial Services, London), Pension funds increased rapidly in recent year. Pension funds always have different ways to build up. One form always from the institutional investment and the funds will build up during the working life by the worker's company and then workers use the funds as the retirement income during workers retired. Alternatively some employees invest in a fund of their choosing and the money can be used to buy an annuity to obtain the pension funds. For this form, one of the important forms of stock market investments of pension funds is shares and bonds.展开更多
Results on the composite generalized Laguerre-Legendre interpolation in unbounded domains are established. As an application,a composite Laguerre-Legendre pseudospectral scheme is presented for nonlinear Fokker-Planck...Results on the composite generalized Laguerre-Legendre interpolation in unbounded domains are established. As an application,a composite Laguerre-Legendre pseudospectral scheme is presented for nonlinear Fokker-Planck equations on the whole line. The convergence and the stability of the proposed scheme are proved. Numerical results show the efficiency of the scheme and conform well to theoretical analysis.展开更多
We consider solving integral equations of the second kind defined on the half-line [0, infinity) by the preconditioned conjugate gradient method. Convergence is known to be slow due to the non-compactness of the assoc...We consider solving integral equations of the second kind defined on the half-line [0, infinity) by the preconditioned conjugate gradient method. Convergence is known to be slow due to the non-compactness of the associated integral operator. In this paper, we construct two different circulant integral operators to be used as preconditioners for the method to speed up its convergence rate. We prove that if the given integral operator is close to a convolution-type integral operator, then the preconditioned systems will have spectrum clustered around 1 and hence the preconditioned conjugate gradient method will converge superlinearly. Numerical examples are given to illustrate the fast convergence.展开更多
基金Supported by the National Social Science Foundation of China(20BTJ048)Anhui University Humanities and Social Science Research Major Project(SK2021ZD0043)。
文摘This paper mainly studies the optimal investment problem of defined contribution(DC)pension under the self-protection and minimum security.First,we apply Ito?theorem to obtain the differential equation of the real stock price after discounting inflation.Then,under the constraint of external guarantee of DC pension terminal wealth,self-protection is introduced to study the maximization of the expected utility of terminal wealth at retirement time and any time before retirement.The explicit solution of the optimal investment strategy of DC pension at retirement time and any time before retirement should be derived by martingale method.Finally,the influence of selfprotection on the optimal investment strategy of DC pension is numerically analyzed.
基金supported in part by the“973”Program of China under Grant No.2013CB329103the National Natural Science Foundation of China under Grant No.61271171 and No.61401070+1 种基金National Key Research and Development Program of China No.2016YFB0800105the“863”Program of China under Grant No.2015AA015702 and No.2015AA016102
文摘Distributed Denial of Service(DDoS) attacks have been one of the most destructive threats to Internet security. By decoupling the network control and data plane, software defined networking(SDN) offers a flexible network management paradigm to solve DDoS attack in traditional networks. However, the centralized nature of SDN is also a potential vulnerability for DDo S attack. In this paper, we first provide some SDN-supported mechanisms against DDoS attack in traditional networks. A systematic review of various SDN-self DDo S threats are then presented as well as the existing literatures on quickly DDoS detection and defense in SDN. Finally, some promising research directions in this field are introduced.
文摘According to the data from IFSL(International Financial Services, London), Pension funds increased rapidly in recent year. Pension funds always have different ways to build up. One form always from the institutional investment and the funds will build up during the working life by the worker's company and then workers use the funds as the retirement income during workers retired. Alternatively some employees invest in a fund of their choosing and the money can be used to buy an annuity to obtain the pension funds. For this form, one of the important forms of stock market investments of pension funds is shares and bonds.
文摘Results on the composite generalized Laguerre-Legendre interpolation in unbounded domains are established. As an application,a composite Laguerre-Legendre pseudospectral scheme is presented for nonlinear Fokker-Planck equations on the whole line. The convergence and the stability of the proposed scheme are proved. Numerical results show the efficiency of the scheme and conform well to theoretical analysis.
文摘We consider solving integral equations of the second kind defined on the half-line [0, infinity) by the preconditioned conjugate gradient method. Convergence is known to be slow due to the non-compactness of the associated integral operator. In this paper, we construct two different circulant integral operators to be used as preconditioners for the method to speed up its convergence rate. We prove that if the given integral operator is close to a convolution-type integral operator, then the preconditioned systems will have spectrum clustered around 1 and hence the preconditioned conjugate gradient method will converge superlinearly. Numerical examples are given to illustrate the fast convergence.
