This paper presents a new adaptive mutation approach for fastening the convergence of immune algorithms (IAs). This method is adopted to realize the twin goals of maintaining diversity in the population and sustaining...This paper presents a new adaptive mutation approach for fastening the convergence of immune algorithms (IAs). This method is adopted to realize the twin goals of maintaining diversity in the population and sustaining the convergence capacity of the IA. In this method, the mutation rate (pm) is adaptively varied depending on the fitness values of the solutions. Solutions of high fitness are protected, while solutions with sub-average fitness are totally disrupted. A solution to the problem of deciding the optimal value of pm is obtained. Experiments are carried out to compare the proposed approach to traditional one on a set of optimization problems. These are namely: 1) an exponential multi-variable function;2) a rapidly varying multimodal function and 3) design of a second order 2-D narrow band recursive LPF. Simulation results show that the proposed method efficiently improves IA’s performance and prevents it from getting stuck at a local optimum.展开更多
This paper presents a dynamic optical phantom for the simulation of metabolic activities in the brain,and a linear equivalent model is built for control voltage versus substance concentration.A solid-solid dynamic opt...This paper presents a dynamic optical phantom for the simulation of metabolic activities in the brain,and a linear equivalent model is built for control voltage versus substance concentration.A solid-solid dynamic optical phantom is realized by using liquid crystal film as a voltage-controlled light intensity regulator on the surface of basic phantom,which uses epoxy resin as matrix material and nanometer carbon powder and titanium dioxide powder as absorption and scattering dopants,respectively.The dynamic phantom could mimic near-infrared spectrum(NIRS)signals with sampling rate up to 10 Hz,and the maximum simulation errors for oxy-hemoglobin and deoxy-hemoglobin concentrations varying in the range of 1μmol/l are 7.0%and 17.9%,respectively.Compared with similar solid biomimetic phantoms,the adjustable mimic substance concentration range is extended by an order of magnitude,which meets the simulation requirements of most brain NIRS signals.展开更多
文摘This paper presents a new adaptive mutation approach for fastening the convergence of immune algorithms (IAs). This method is adopted to realize the twin goals of maintaining diversity in the population and sustaining the convergence capacity of the IA. In this method, the mutation rate (pm) is adaptively varied depending on the fitness values of the solutions. Solutions of high fitness are protected, while solutions with sub-average fitness are totally disrupted. A solution to the problem of deciding the optimal value of pm is obtained. Experiments are carried out to compare the proposed approach to traditional one on a set of optimization problems. These are namely: 1) an exponential multi-variable function;2) a rapidly varying multimodal function and 3) design of a second order 2-D narrow band recursive LPF. Simulation results show that the proposed method efficiently improves IA’s performance and prevents it from getting stuck at a local optimum.
基金supported by the National Key Research and Development Program of China under Grant No.STI2030-Major Projects 2022ZD0208500.
文摘This paper presents a dynamic optical phantom for the simulation of metabolic activities in the brain,and a linear equivalent model is built for control voltage versus substance concentration.A solid-solid dynamic optical phantom is realized by using liquid crystal film as a voltage-controlled light intensity regulator on the surface of basic phantom,which uses epoxy resin as matrix material and nanometer carbon powder and titanium dioxide powder as absorption and scattering dopants,respectively.The dynamic phantom could mimic near-infrared spectrum(NIRS)signals with sampling rate up to 10 Hz,and the maximum simulation errors for oxy-hemoglobin and deoxy-hemoglobin concentrations varying in the range of 1μmol/l are 7.0%and 17.9%,respectively.Compared with similar solid biomimetic phantoms,the adjustable mimic substance concentration range is extended by an order of magnitude,which meets the simulation requirements of most brain NIRS signals.