Fiber quarter-wave plates and magneto-optical fibers are important components that greatly affect the sensitivity of fiberoptic current sensors.A Tb:YAG crystal-derived silica fiber(TYDSF)was fabricated using a CO_(2)...Fiber quarter-wave plates and magneto-optical fibers are important components that greatly affect the sensitivity of fiberoptic current sensors.A Tb:YAG crystal-derived silica fiber(TYDSF)was fabricated using a CO_(2) laser-heating drawing technique.The linear birefringence of TYDSF was measured as 6.661×10^(-6)by a microscope birefringence measurement instrument.A fiber quarter-wave plate was fabricated by TYDSF at 1310 nm,which produced circularly polarized light with a polarization extinction ratio of 0.34 d B.Additionally,the linear birefringence of TYDSF was decreased by 22%by annealing at 750℃ for 7 h,and the Verdet constants of annealed TYDSF were measured to be 9.83,6.67,and 3.48 rad/(T·m)at 808,980,and 1310 nm,respectively.展开更多
In this paper, we consider an insurer who wants to maximize its expected utility of terminal wealth by selecting optimal investment and risk control strategies. The insurer’s risk process is modeled by a jump-diffusi...In this paper, we consider an insurer who wants to maximize its expected utility of terminal wealth by selecting optimal investment and risk control strategies. The insurer’s risk process is modeled by a jump-diffusion process and is negatively correlated with the returns of securities and derivatives in the financial market. In the financial model, a part of insurers’ wealth is invested into the financial market. Using a martingale approach, we obtain an explicit solution of optimal strategy for the insurer under logarithmic utility function.展开更多
基金supported by the National Natural Science Foundation of China(Nos.61935002,61975113,and 62275148)the 111 Project(No.D20031),the Shanghai Professional Technical Public Service Platform of Advanced Optical Waveguide Intelligent Manufacturing and Testing(No.19DZ2294000)the Jiangsu Province’s Industry OutlookandKeyCoreTechnologies–KeyProjects(No.BE2022055-4)。
文摘Fiber quarter-wave plates and magneto-optical fibers are important components that greatly affect the sensitivity of fiberoptic current sensors.A Tb:YAG crystal-derived silica fiber(TYDSF)was fabricated using a CO_(2) laser-heating drawing technique.The linear birefringence of TYDSF was measured as 6.661×10^(-6)by a microscope birefringence measurement instrument.A fiber quarter-wave plate was fabricated by TYDSF at 1310 nm,which produced circularly polarized light with a polarization extinction ratio of 0.34 d B.Additionally,the linear birefringence of TYDSF was decreased by 22%by annealing at 750℃ for 7 h,and the Verdet constants of annealed TYDSF were measured to be 9.83,6.67,and 3.48 rad/(T·m)at 808,980,and 1310 nm,respectively.
文摘In this paper, we consider an insurer who wants to maximize its expected utility of terminal wealth by selecting optimal investment and risk control strategies. The insurer’s risk process is modeled by a jump-diffusion process and is negatively correlated with the returns of securities and derivatives in the financial market. In the financial model, a part of insurers’ wealth is invested into the financial market. Using a martingale approach, we obtain an explicit solution of optimal strategy for the insurer under logarithmic utility function.