By combining of the second gradient operator, the second class of integral theorems, the Gaussian-curvature-based integral theorems and the Gaussian （or spherical） mapping, a series of invariants or geometric conser...By combining of the second gradient operator, the second class of integral theorems, the Gaussian-curvature-based integral theorems and the Gaussian （or spherical） mapping, a series of invariants or geometric conservation quantities under Gaussian （or spherical） mapping are revealed. From these mapping invariants important transformations between original curved surface and the spherical surface are derived. The potential applications of these invariants and transformations to geometry are discussed展开更多
In this paper,a reinforced gradient-type iterative learning control pro file is proposed by making use of system matrices and a proper learning step to improve the tracking performance of batch processes disturbed by ...In this paper,a reinforced gradient-type iterative learning control pro file is proposed by making use of system matrices and a proper learning step to improve the tracking performance of batch processes disturbed by external Gaussian white noise.The robustness is analyzed and the range of the step is speci fied by means of statistical technique and matrix theory.Compared with the conventional one,the proposed algorithm is more ef ficient to resist external noise.Numerical simulations of an injection molding process illustrate that the proposed scheme is feasible and effective.展开更多
The partially coherent beams propagating through random media have been used in the past to enhance effect of nonlinear optical interaction. Moreover, after propagation through a random （or turbulent） medium the coh...The partially coherent beams propagating through random media have been used in the past to enhance effect of nonlinear optical interaction. Moreover, after propagation through a random （or turbulent） medium the coherent beam becomes a partially coherent one. In this research, the analytical formula for the average intensity of Gaussian beam propagating through random medium is derived and the influence of coherent partiality on optical gradient force acting on dielectric particle rounded by a random media is investigated.展开更多
In this work, we use the analytical expression of the propagation of Finite Olver-Gaussian beams (FOGBs) through a paraxial ABCD optical system to study the action of radiation forces produced by highly focused FOGBs ...In this work, we use the analytical expression of the propagation of Finite Olver-Gaussian beams (FOGBs) through a paraxial ABCD optical system to study the action of radiation forces produced by highly focused FOGBs on a Rayleigh dielectric sphere. Our numerical results show that the FOGBs can be employed to trap and manipulate particles with the refractive index larger than that of the ambient. The radiation force distribution has been studied under different beam widths. The trapping stability under different conditions is also analyzed.展开更多
Accelerated proximal gradient methods have recently been developed for solving quasi-static incremental problems of elastoplastic analysis with some different yield criteria.It has been demonstrated through numerical ...Accelerated proximal gradient methods have recently been developed for solving quasi-static incremental problems of elastoplastic analysis with some different yield criteria.It has been demonstrated through numerical experiments that these methods can outperform conventional optimization-based approaches in computational plasticity.However,in literature these algorithms are described individually for specific yield criteria,and hence there exists no guide for application of the algorithms to other yield criteria.This short paper presents a general form of algorithm design,independent of specific forms of yield criteria,that unifies the existing proximal gradient methods.Clear interpretation is also given to each step of the presented general algorithm so that each update rule is linked to the underlying physical laws in terms of mechanical quantities.展开更多
In this paper,we study a class of Finsler metrics defined by a vector field on a gradient Ricci soliton.We obtain a necessary and sufficient condition for these Finsler metrics on a compact gradient Ricci soliton to b...In this paper,we study a class of Finsler metrics defined by a vector field on a gradient Ricci soliton.We obtain a necessary and sufficient condition for these Finsler metrics on a compact gradient Ricci soliton to be of isotropic S-curvature by establishing a new integral inequality.Then we determine the Ricci curvature of navigation Finsler metrics of isotropic S-curvature on a gradient Ricci soliton generalizing result only known in the case when such soliton is of Einstein type.As its application,we obtain the Ricci curvature of all navigation Finsler metrics of isotropic S-curvature on Gaussian shrinking soliton.展开更多
Very few studies have benefited from the synergetic implementation of visible,near-infrared,and shortwave infrared(VNIR-SWIR)spectra and terrain attributes in predicting Pb content in agricultural soils.To fill this g...Very few studies have benefited from the synergetic implementation of visible,near-infrared,and shortwave infrared(VNIR-SWIR)spectra and terrain attributes in predicting Pb content in agricultural soils.To fill this gap,this study aimed to predict lead(Pb)contents in agricultural soils by combining machine learning algorithms(MLAs)with VNIR-SWIR spectra or/and terrain attributes under three distinct approaches.Six MLAs were tested,including artificial neural network(ANN),partial least squares regression,support vector machine(SVM),Gaussian process regression(GPR),extreme gradient boosting(EGB),and Cubist.The VNIR-SWIR spectral data were preprocessed by methods of discrete wavelet transformation,logarithmic transformation-Savitzky Golay smoothing,standard normal variate(SNV),multiplicative scatter correction,first derivative(Fi D),and second derivative.In approach 1,MLAs were combined with the preprocessed VNIR-SWIR spectral data.The Cubist-Fi D combination was the most effective,achieving a coefficient of determination(R2)of 0.63,a concordance correlation coefficient(CCC)of 0.51,a mean absolute error(MAE)of 6.87 mg kg^(-1),and a root mean square error(RMSE)of8.66 mg kg^(-1).In approach 2,MLAs were combined with both preprocessed VNIR-SWIR spectral data and terrain attributes,and the EGB-SNV combination yielded superior results with R2of 0.75,CCC of 0.65,MAE of 5.48 mg kg^(-1),and RMSE of 7.34 mg kg^(-1).Approach 3 combined MLAs and terrain attributes,and Cubist demonstrated the best prediction results,with R^(2) of 0.75,CCC of 0.66,MAE of 6.18 mg kg^(-1),and RMSE of 7.71 mg kg^(-1).The cumulative assessment identified the fusion of terrain properties,SNV-preprocessed VNIR-SWIR spectra,and EGB as the optimal method for estimating Pb content in agricultural soils,yielding the highest R2value and minimal error.Comparatively,GPR,ANN,and SVM techniques achieved higher R2values in approaches 2 and 3 but also exhibited higher estimation errors.In conclusion,the study underscores the significance of using relevant auxiliary datasets and appropriate MLAs for accurate Pb content prediction with minimal error in agricultural soils.The findings contribute valuable insights for developing successful soil management strategies based on predictive modeling.展开更多
基金Project supported by the National Natural Science Foundation of China (No.10572076)
文摘By combining of the second gradient operator, the second class of integral theorems, the Gaussian-curvature-based integral theorems and the Gaussian （or spherical） mapping, a series of invariants or geometric conservation quantities under Gaussian （or spherical） mapping are revealed. From these mapping invariants important transformations between original curved surface and the spherical surface are derived. The potential applications of these invariants and transformations to geometry are discussed
基金Supported by National Natural Science Foundation of China(F010114-6097414061273135)
文摘In this paper,a reinforced gradient-type iterative learning control pro file is proposed by making use of system matrices and a proper learning step to improve the tracking performance of batch processes disturbed by external Gaussian white noise.The robustness is analyzed and the range of the step is speci fied by means of statistical technique and matrix theory.Compared with the conventional one,the proposed algorithm is more ef ficient to resist external noise.Numerical simulations of an injection molding process illustrate that the proposed scheme is feasible and effective.
文摘The partially coherent beams propagating through random media have been used in the past to enhance effect of nonlinear optical interaction. Moreover, after propagation through a random （or turbulent） medium the coherent beam becomes a partially coherent one. In this research, the analytical formula for the average intensity of Gaussian beam propagating through random medium is derived and the influence of coherent partiality on optical gradient force acting on dielectric particle rounded by a random media is investigated.
文摘In this work, we use the analytical expression of the propagation of Finite Olver-Gaussian beams (FOGBs) through a paraxial ABCD optical system to study the action of radiation forces produced by highly focused FOGBs on a Rayleigh dielectric sphere. Our numerical results show that the FOGBs can be employed to trap and manipulate particles with the refractive index larger than that of the ambient. The radiation force distribution has been studied under different beam widths. The trapping stability under different conditions is also analyzed.
文摘Accelerated proximal gradient methods have recently been developed for solving quasi-static incremental problems of elastoplastic analysis with some different yield criteria.It has been demonstrated through numerical experiments that these methods can outperform conventional optimization-based approaches in computational plasticity.However,in literature these algorithms are described individually for specific yield criteria,and hence there exists no guide for application of the algorithms to other yield criteria.This short paper presents a general form of algorithm design,independent of specific forms of yield criteria,that unifies the existing proximal gradient methods.Clear interpretation is also given to each step of the presented general algorithm so that each update rule is linked to the underlying physical laws in terms of mechanical quantities.
基金Supported by the National Natural Science Foundation of China(11771020,12171005).
文摘In this paper,we study a class of Finsler metrics defined by a vector field on a gradient Ricci soliton.We obtain a necessary and sufficient condition for these Finsler metrics on a compact gradient Ricci soliton to be of isotropic S-curvature by establishing a new integral inequality.Then we determine the Ricci curvature of navigation Finsler metrics of isotropic S-curvature on a gradient Ricci soliton generalizing result only known in the case when such soliton is of Einstein type.As its application,we obtain the Ricci curvature of all navigation Finsler metrics of isotropic S-curvature on Gaussian shrinking soliton.
基金supported by an institutional Ph.D.grant(No.21130/1312/3131)from the Faculty of Agrobiology,Food,and Natural Resources at the Czech University of Life Sciences Prague(CZU),Czech Republic。
文摘Very few studies have benefited from the synergetic implementation of visible,near-infrared,and shortwave infrared(VNIR-SWIR)spectra and terrain attributes in predicting Pb content in agricultural soils.To fill this gap,this study aimed to predict lead(Pb)contents in agricultural soils by combining machine learning algorithms(MLAs)with VNIR-SWIR spectra or/and terrain attributes under three distinct approaches.Six MLAs were tested,including artificial neural network(ANN),partial least squares regression,support vector machine(SVM),Gaussian process regression(GPR),extreme gradient boosting(EGB),and Cubist.The VNIR-SWIR spectral data were preprocessed by methods of discrete wavelet transformation,logarithmic transformation-Savitzky Golay smoothing,standard normal variate(SNV),multiplicative scatter correction,first derivative(Fi D),and second derivative.In approach 1,MLAs were combined with the preprocessed VNIR-SWIR spectral data.The Cubist-Fi D combination was the most effective,achieving a coefficient of determination(R2)of 0.63,a concordance correlation coefficient(CCC)of 0.51,a mean absolute error(MAE)of 6.87 mg kg^(-1),and a root mean square error(RMSE)of8.66 mg kg^(-1).In approach 2,MLAs were combined with both preprocessed VNIR-SWIR spectral data and terrain attributes,and the EGB-SNV combination yielded superior results with R2of 0.75,CCC of 0.65,MAE of 5.48 mg kg^(-1),and RMSE of 7.34 mg kg^(-1).Approach 3 combined MLAs and terrain attributes,and Cubist demonstrated the best prediction results,with R^(2) of 0.75,CCC of 0.66,MAE of 6.18 mg kg^(-1),and RMSE of 7.71 mg kg^(-1).The cumulative assessment identified the fusion of terrain properties,SNV-preprocessed VNIR-SWIR spectra,and EGB as the optimal method for estimating Pb content in agricultural soils,yielding the highest R2value and minimal error.Comparatively,GPR,ANN,and SVM techniques achieved higher R2values in approaches 2 and 3 but also exhibited higher estimation errors.In conclusion,the study underscores the significance of using relevant auxiliary datasets and appropriate MLAs for accurate Pb content prediction with minimal error in agricultural soils.The findings contribute valuable insights for developing successful soil management strategies based on predictive modeling.
