We consider an extension to Sequential Probability Ratio Tests for when we have uncertain costs, but also opportunity to learn about these in an adaptive manner. In doing so we demonstrate the effects that allowing un...We consider an extension to Sequential Probability Ratio Tests for when we have uncertain costs, but also opportunity to learn about these in an adaptive manner. In doing so we demonstrate the effects that allowing uncertainty has on observation cost, and the costs associated with Type I and Type II error. The value of information relating to modelled uncertainties is derived and the case of statistical dependence between the parameter affecting decision outcome and the parameter affecting unknown cost is also examined. Numerical examples of the derived theory are provided, along with a simulation comparing this adaptive learning framework to the classical one.展开更多
In the system of Computer Network Collaborative Defense(CNCD),it is difficult to evaluate the trustworthiness of defense agents which are newly added to the system,since they lack historical interaction for trust eval...In the system of Computer Network Collaborative Defense(CNCD),it is difficult to evaluate the trustworthiness of defense agents which are newly added to the system,since they lack historical interaction for trust evaluation.This will lead that the newly added agents could not get reasonable initial trustworthiness,and affect the whole process of trust evaluation.To solve this problem in CNCD,a trust type based trust bootstrapping model was introduced in this research.First,the division of trust type,trust utility and defense cost were discussed.Then the constraints of defense tasks were analyzed based on game theory.According to the constraints obtained,the trust type of defense agents was identified and the initial trustworthiness was assigned to defense agents.The simulated experiment shows that the methods proposed have lower failure rate of defense tasks and better adaptability in the respect of defense task execution.展开更多
When the permanent magnet high-speed Electrical Multiple Unit(EMU)train runs at extremely high speeds,it is necessary to solve the problem of optimal exertion of wheel-rail adhesion to ensure the adhesion utilization ...When the permanent magnet high-speed Electrical Multiple Unit(EMU)train runs at extremely high speeds,it is necessary to solve the problem of optimal exertion of wheel-rail adhesion to ensure the adhesion utilization rate of the train and the smooth and safe operation of the vehicle.To improve the adhesion utilization rate of the train and passenger comfort,this paper proposes an adaptive adhesion utilization control strategy for permanent magnet high-speed EMU trains.This method automatically identifies the wheelrail state,matches the wheel-rail adhesion characteristics,automatically adjusts the adhesion control parameters according to the wheelset idling and sliding state,reduces the fluctuation range of traction force,improves the stability of traction force exertion and effectively improves the adhesion utilization control performance of the permanent magnet high-speed EMU train.Both simulation and experimental tests demonstrate this method’s superiority over traditional control methods.It has been shown to enhance adhesion utilization efficiency by over 5%and to significantly narrow the traction force adjustment range by more than 10%.It also improves passenger comfort indicators such as train stability and comfort,and enhances the safety of train operation.展开更多
文摘We consider an extension to Sequential Probability Ratio Tests for when we have uncertain costs, but also opportunity to learn about these in an adaptive manner. In doing so we demonstrate the effects that allowing uncertainty has on observation cost, and the costs associated with Type I and Type II error. The value of information relating to modelled uncertainties is derived and the case of statistical dependence between the parameter affecting decision outcome and the parameter affecting unknown cost is also examined. Numerical examples of the derived theory are provided, along with a simulation comparing this adaptive learning framework to the classical one.
基金supported by the National Natural Science Foundation of China under Grant No.61170295
文摘In the system of Computer Network Collaborative Defense(CNCD),it is difficult to evaluate the trustworthiness of defense agents which are newly added to the system,since they lack historical interaction for trust evaluation.This will lead that the newly added agents could not get reasonable initial trustworthiness,and affect the whole process of trust evaluation.To solve this problem in CNCD,a trust type based trust bootstrapping model was introduced in this research.First,the division of trust type,trust utility and defense cost were discussed.Then the constraints of defense tasks were analyzed based on game theory.According to the constraints obtained,the trust type of defense agents was identified and the initial trustworthiness was assigned to defense agents.The simulated experiment shows that the methods proposed have lower failure rate of defense tasks and better adaptability in the respect of defense task execution.
文摘When the permanent magnet high-speed Electrical Multiple Unit(EMU)train runs at extremely high speeds,it is necessary to solve the problem of optimal exertion of wheel-rail adhesion to ensure the adhesion utilization rate of the train and the smooth and safe operation of the vehicle.To improve the adhesion utilization rate of the train and passenger comfort,this paper proposes an adaptive adhesion utilization control strategy for permanent magnet high-speed EMU trains.This method automatically identifies the wheelrail state,matches the wheel-rail adhesion characteristics,automatically adjusts the adhesion control parameters according to the wheelset idling and sliding state,reduces the fluctuation range of traction force,improves the stability of traction force exertion and effectively improves the adhesion utilization control performance of the permanent magnet high-speed EMU train.Both simulation and experimental tests demonstrate this method’s superiority over traditional control methods.It has been shown to enhance adhesion utilization efficiency by over 5%and to significantly narrow the traction force adjustment range by more than 10%.It also improves passenger comfort indicators such as train stability and comfort,and enhances the safety of train operation.
