A new method for computing numerical solutions to the inverse kinematics problem of robotic manipulators is developed in this paper.With the joint limitations,the electromagnetism-like method(EM)utilizes an attraction...A new method for computing numerical solutions to the inverse kinematics problem of robotic manipulators is developed in this paper.With the joint limitations,the electromagnetism-like method(EM)utilizes an attraction-repulsion mechanism to move the sample points towards the optimum solution rapidly.Based on this approximate solution given by EM,a modified DavidonFletcher-Powell(DFP)algorithm is developed to solve the problem at the desired precision.Unlike the traditional algorithms,this modified DFP(MDFP)algorithm randomly chooses the search step size between 0 and 1.Hence,the computational complexity is greatly reduced.The experimental results based on ten general test functions and PUMA 560 robot show that this new near-real time hybrid method can produce best performance.展开更多
This paper deals with the mean-square exponential input-to-state stability(exp-ISS)of Euler-Maruyama(EM)method applied to stochastic control systems(SCSs).The aim is to find out the conditions of the exact and EM meth...This paper deals with the mean-square exponential input-to-state stability(exp-ISS)of Euler-Maruyama(EM)method applied to stochastic control systems(SCSs).The aim is to find out the conditions of the exact and EM method solutions to an SCS having the property of mean-square exp-ISS without involving control Lyapunov functions.Second moment boundedness and an appropriate form of strong convergence are achieved under global Lipschitz coeffcients and mean-square continuous random inputs.Under the strong convergent condition,it is shown that the mean-square exp-ISS of an SCS holds if and only if that of the EM method is preserved for suffciently small step size.展开更多
This paper develops the mean-square exponential input-to-state stability（exp-ISS） of the Euler-Maruyama（EM） method for stochastic delay control systems（SDCSs）.The definition of mean-square exp-ISS of numerical m...This paper develops the mean-square exponential input-to-state stability（exp-ISS） of the Euler-Maruyama（EM） method for stochastic delay control systems（SDCSs）.The definition of mean-square exp-ISS of numerical methods is established.The conditions of the exact and EM method for an SDCS with the property of mean-square exp-ISS are obtained without involving control Lyapunov functions or functional.Under the global Lipschitz coefficients and mean-square continuous measurable inputs,it is proved that the mean-square exp-ISS of an SDCS holds if and only if that of the EM method is preserved for a sufficiently small step size.The proposed results are evaluated by using numerical experiments to show their effectiveness.展开更多
As a new-style stochastic algorithm, the electromagnetism-like mechanism（EM） method gains more and more attention from many researchers in recent years. A novel model based on EM（NMEM） for multiobjective optimizat...As a new-style stochastic algorithm, the electromagnetism-like mechanism（EM） method gains more and more attention from many researchers in recent years. A novel model based on EM（NMEM） for multiobjective optimization problems is proposed, which regards the charge of all particles as the constraints in the current population and the measure of the uniformity of non-dominated solutions as the objective function. The charge of the particle is evaluated based on the dominated concept, and its magnitude determines the direction of a force between two particles. Numerical studies are carried out on six complex test functions and the experimental results demonstrate that the proposed NMEM algorithm is a very robust method for solving the multiobjective optimization problems.展开更多
Calculations of the ElectroMagnetic(EM) response produced by a large horizontal loop placed over layered medium are rather complex because its integral expression contains the product of two Bessel functions and has a...Calculations of the ElectroMagnetic(EM) response produced by a large horizontal loop placed over layered medium are rather complex because its integral expression contains the product of two Bessel functions and has a divergent term. In this paper, an improved fast Hankel and Gaver-Stehfest transforms are introduced to solve the strong-oscillation and slow-decay properties of the integrand, where one Bessel function in the product is substituted by a carefully chosen polynomial of high accuracy and the other used as the digital filter coefficients in the convolution integral. Comparisons prove the validity and the efficiency of the proposed method.展开更多
Realising the importance of pore fluid salinity on the dewatering behaviour of fine-grained porous systems,the present study systematically investigated such impacts on temporal moisture dynamics of kaolin subjected t...Realising the importance of pore fluid salinity on the dewatering behaviour of fine-grained porous systems,the present study systematically investigated such impacts on temporal moisture dynamics of kaolin subjected to evaporative dewatering.A detailed discussion is provided pertaining to the background processes dictating evaporative dewatering response and corresponding alterations in the dielectric behaviour of kaolin.Frequency dependent dielectric spectra of soil,which can be considered as the fingerprint of the transient changes in the condition of water phase within the pore system of the soil and associated densification,are monitored in real time during dewatering using an open-ended coaxial probe with a vector network analyser.The spatial sensitivity of the coaxial probe has been quantified through layered media approach.Combining the results of volume change behaviour of the material along with its moisture loss response,the study characterised the hydro-mechanical response of the material from the windows of frequency dependent dielectric spectroscopy.展开更多
This paper builds on exploring the applications of biomediated pathways to solve geotechnical challenges.First,the state of the art of biological remediation strategies including microbial remediation and phytoremedia...This paper builds on exploring the applications of biomediated pathways to solve geotechnical challenges.First,the state of the art of biological remediation strategies including microbial remediation and phytoremediation have been introduced and critically reviewed in the context of decontaminating the soils.Next,biopolymerisation,biomineralisation and bioneutralisation processes have been depicted with a special emphasis on the applications including but not limited to soil stabilisation,soil erosion prevention,anti-desertification and pH neutralisation.Each of these methods have their own limitations and bottlenecks while scaling up,and these challenges have been summarised and some possible paths to overcome the challenges have also been discussed.The state of the art of electromagnetic(EM)monitoring methods to capture the effects of biomediation on spatio-temporal soil properties are then highlighted as a non-invasive and rapid pathway to track the progress of biomediated soil processes.Finally,each of the technologies discussed have been evaluated for their maturity level using the principles of technology readiness level(TRL).A majority of the technologies amounting to around 77%are still in the TRL 4e7,i.e.in the valley of death.It is thus evident that development of these technologies needs to be supported with appropriate funding for improving their maturity to a level of industrial deployment.展开更多
The inverse black body radiation problem, which is to reconstruct the area temperature distribution from the measurement of power spectrum distribution, is a well-known ill-posed problem. In this paper, a variational ...The inverse black body radiation problem, which is to reconstruct the area temperature distribution from the measurement of power spectrum distribution, is a well-known ill-posed problem. In this paper, a variational expectation-maximization （EM） method is developed and its convergence is studied. Numerical experiments demonstrate that the variational EM method is more efficient and accurate than the traditional methods, including the Tikhonov regularization method, the Landweber method and the conjugate gradient method.展开更多
This work is concerned with the convergence and stability of the truncated EulerMaruyama(EM)method for super-linear stochastic differential delay equations(SDDEs)with time-variable delay and Poisson jumps.By construct...This work is concerned with the convergence and stability of the truncated EulerMaruyama(EM)method for super-linear stochastic differential delay equations(SDDEs)with time-variable delay and Poisson jumps.By constructing appropriate truncated functions to control the super-linear growth of the original coefficients,we present two types of the truncated EM method for such jump-diffusion SDDEs with time-variable delay,which is proposed to be approximated by the value taken at the nearest grid points on the left of the delayed argument.The first type is proved to have a strong convergence order which is arbitrarily close to 1/2 in mean-square sense,under the Khasminskii-type,global monotonicity with U function and polynomial growth conditions.The second type is convergent in q-th(q<2)moment under the local Lipschitz plus generalized Khasminskii-type conditions.In addition,we show that the partially truncated EM method preserves the mean-square and H∞stabilities of the true solutions.Lastly,we carry out some numerical experiments to support the theoretical results.展开更多
基金Supported by National High Technology Research and Development Program of China(863 Program)(2008AA04Z214)National Natural Science Foundation of China(2008BAF36B01)
文摘A new method for computing numerical solutions to the inverse kinematics problem of robotic manipulators is developed in this paper.With the joint limitations,the electromagnetism-like method(EM)utilizes an attraction-repulsion mechanism to move the sample points towards the optimum solution rapidly.Based on this approximate solution given by EM,a modified DavidonFletcher-Powell(DFP)algorithm is developed to solve the problem at the desired precision.Unlike the traditional algorithms,this modified DFP(MDFP)algorithm randomly chooses the search step size between 0 and 1.Hence,the computational complexity is greatly reduced.The experimental results based on ten general test functions and PUMA 560 robot show that this new near-real time hybrid method can produce best performance.
基金Supported by National Natural Science Foundation of China(10571036)the Key Discipline Development Program of Beijing Municipal Commission(XK100080537)
文摘This paper deals with the mean-square exponential input-to-state stability(exp-ISS)of Euler-Maruyama(EM)method applied to stochastic control systems(SCSs).The aim is to find out the conditions of the exact and EM method solutions to an SCS having the property of mean-square exp-ISS without involving control Lyapunov functions.Second moment boundedness and an appropriate form of strong convergence are achieved under global Lipschitz coeffcients and mean-square continuous random inputs.Under the strong convergent condition,it is shown that the mean-square exp-ISS of an SCS holds if and only if that of the EM method is preserved for suffciently small step size.
基金supported by the National Natural Science Foundation of China(6127312660904032)the Natural Science Foundation of Guangdong Province(10251064101000008)
文摘This paper develops the mean-square exponential input-to-state stability（exp-ISS） of the Euler-Maruyama（EM） method for stochastic delay control systems（SDCSs）.The definition of mean-square exp-ISS of numerical methods is established.The conditions of the exact and EM method for an SDCS with the property of mean-square exp-ISS are obtained without involving control Lyapunov functions or functional.Under the global Lipschitz coefficients and mean-square continuous measurable inputs,it is proved that the mean-square exp-ISS of an SDCS holds if and only if that of the EM method is preserved for a sufficiently small step size.The proposed results are evaluated by using numerical experiments to show their effectiveness.
基金supported by the National Natural Science Foundation of China(60873099)the Fundamental Research Funds for the Central Universities(2011QNA29)
文摘As a new-style stochastic algorithm, the electromagnetism-like mechanism（EM） method gains more and more attention from many researchers in recent years. A novel model based on EM（NMEM） for multiobjective optimization problems is proposed, which regards the charge of all particles as the constraints in the current population and the measure of the uniformity of non-dominated solutions as the objective function. The charge of the particle is evaluated based on the dominated concept, and its magnitude determines the direction of a force between two particles. Numerical studies are carried out on six complex test functions and the experimental results demonstrate that the proposed NMEM algorithm is a very robust method for solving the multiobjective optimization problems.
基金Supported by Chinese Government SinoProbe Plan(No.SinoProbe-09-02)R&D of Key Instruments and Technologies for Deep Resources Prospecting(No.ZDYZ 2012-1-03)
文摘Calculations of the ElectroMagnetic(EM) response produced by a large horizontal loop placed over layered medium are rather complex because its integral expression contains the product of two Bessel functions and has a divergent term. In this paper, an improved fast Hankel and Gaver-Stehfest transforms are introduced to solve the strong-oscillation and slow-decay properties of the integrand, where one Bessel function in the product is substituted by a carefully chosen polynomial of high accuracy and the other used as the digital filter coefficients in the convolution integral. Comparisons prove the validity and the efficiency of the proposed method.
基金supported through’Australian Government Research Training Program Scholarship’(formerly’International Postgraduate Research Scholarship’)UQ Centennial Scholarship(the University of Queensland)+1 种基金Top-up Scholarship(School of Civil Engineering,the University of Queensland)awarded to Mr.P.N.Mishrathe Port of Brisbane/UQ research venture.
文摘Realising the importance of pore fluid salinity on the dewatering behaviour of fine-grained porous systems,the present study systematically investigated such impacts on temporal moisture dynamics of kaolin subjected to evaporative dewatering.A detailed discussion is provided pertaining to the background processes dictating evaporative dewatering response and corresponding alterations in the dielectric behaviour of kaolin.Frequency dependent dielectric spectra of soil,which can be considered as the fingerprint of the transient changes in the condition of water phase within the pore system of the soil and associated densification,are monitored in real time during dewatering using an open-ended coaxial probe with a vector network analyser.The spatial sensitivity of the coaxial probe has been quantified through layered media approach.Combining the results of volume change behaviour of the material along with its moisture loss response,the study characterised the hydro-mechanical response of the material from the windows of frequency dependent dielectric spectroscopy.
文摘This paper builds on exploring the applications of biomediated pathways to solve geotechnical challenges.First,the state of the art of biological remediation strategies including microbial remediation and phytoremediation have been introduced and critically reviewed in the context of decontaminating the soils.Next,biopolymerisation,biomineralisation and bioneutralisation processes have been depicted with a special emphasis on the applications including but not limited to soil stabilisation,soil erosion prevention,anti-desertification and pH neutralisation.Each of these methods have their own limitations and bottlenecks while scaling up,and these challenges have been summarised and some possible paths to overcome the challenges have also been discussed.The state of the art of electromagnetic(EM)monitoring methods to capture the effects of biomediation on spatio-temporal soil properties are then highlighted as a non-invasive and rapid pathway to track the progress of biomediated soil processes.Finally,each of the technologies discussed have been evaluated for their maturity level using the principles of technology readiness level(TRL).A majority of the technologies amounting to around 77%are still in the TRL 4e7,i.e.in the valley of death.It is thus evident that development of these technologies needs to be supported with appropriate funding for improving their maturity to a level of industrial deployment.
基金the National Basic Research Program of China (2006CB705700)the National Science Foundation of China(60532080)Microsoft Research of Asia
文摘The inverse black body radiation problem, which is to reconstruct the area temperature distribution from the measurement of power spectrum distribution, is a well-known ill-posed problem. In this paper, a variational expectation-maximization （EM） method is developed and its convergence is studied. Numerical experiments demonstrate that the variational EM method is more efficient and accurate than the traditional methods, including the Tikhonov regularization method, the Landweber method and the conjugate gradient method.
基金the National Natural Science Foundation of China(62273003,12271003)the Open Project of Anhui Province Center for International Research of Intelligent Control of High-end Equipment(IRICHE-01)+4 种基金the Natural Science Foundation of Universities in Anhui Province(2022AH050993)the Startup Foundation for Introduction Talent of AHPU(2021YQQ058)the Royal Society(WM160014,Royal Society Wolfson Research Merit Award)the Royal Society and the Newton Fund(NA160317,Royal Society-Newton Advanced Fellowship)the Royal Society of Edinburgh(RSE1832)for their financial support.
文摘This work is concerned with the convergence and stability of the truncated EulerMaruyama(EM)method for super-linear stochastic differential delay equations(SDDEs)with time-variable delay and Poisson jumps.By constructing appropriate truncated functions to control the super-linear growth of the original coefficients,we present two types of the truncated EM method for such jump-diffusion SDDEs with time-variable delay,which is proposed to be approximated by the value taken at the nearest grid points on the left of the delayed argument.The first type is proved to have a strong convergence order which is arbitrarily close to 1/2 in mean-square sense,under the Khasminskii-type,global monotonicity with U function and polynomial growth conditions.The second type is convergent in q-th(q<2)moment under the local Lipschitz plus generalized Khasminskii-type conditions.In addition,we show that the partially truncated EM method preserves the mean-square and H∞stabilities of the true solutions.Lastly,we carry out some numerical experiments to support the theoretical results.
