Non-linear dynamics,fractals,periodic oscillations,bifurcations,chaos,and other terminologies have been used to describe human biological systems in the literature for a few decades.The eight manuscripts included in t...Non-linear dynamics,fractals,periodic oscillations,bifurcations,chaos,and other terminologies have been used to describe human biological systems in the literature for a few decades.The eight manuscripts included in this special issue discussed the historical background,展开更多
The 3-hour-interval prediction of ground-level temperature from +00 h out to +45 h in South Korea (38 stations) is performed using the DLM (dynamic linear model) in order to eliminate the systematic error of numerical...The 3-hour-interval prediction of ground-level temperature from +00 h out to +45 h in South Korea (38 stations) is performed using the DLM (dynamic linear model) in order to eliminate the systematic error of numerical model forecasts. Numerical model forecasts and observations are used as input values of the DLM. According to the comparison of the DLM forecasts to the KFM (Kalman filter model) forecasts with RMSE and bias, the DLM is useful to improve the accuracy of prediction.展开更多
This paper deals with the Hyers-Ulam stability of the nonhomogeneous linear dynamic equation x~?(t)-ax(t) = f(t), where a ∈ R^+. The main results can be regarded as a supplement of the stability results of the corres...This paper deals with the Hyers-Ulam stability of the nonhomogeneous linear dynamic equation x~?(t)-ax(t) = f(t), where a ∈ R^+. The main results can be regarded as a supplement of the stability results of the corresponding homogeneous linear dynamic equation obtained by Anderson and Onitsuka(Anderson D R, Onitsuka M. Hyers-Ulam stability of first-order homogeneous linear dynamic equations on time scales. Demonstratio Math., 2018, 51: 198–210).展开更多
A finite dynamical system(FDS)over a lattice L is a pair(S(L),f),where S(L)is a left-L module and f is a mapping from S into itself.The phase space of(S(L),f)is a digraph whose vertex set is S(L)and there is an arc fr...A finite dynamical system(FDS)over a lattice L is a pair(S(L),f),where S(L)is a left-L module and f is a mapping from S into itself.The phase space of(S(L),f)is a digraph whose vertex set is S(L)and there is an arc from x to y if y=f(x).Let L be a finite distributive lattice,A an n×n matrix over L,and f(x)=Ax.The structure of the phase space of the FDS(Ln,f)is discussed.The number of limit cycles in the phase space of(Ln,f)is described in Möbius function.The phase spaces of some invertible,nilpotent,and idempotent FDS(Ln,f)are characterized explicitly.展开更多
Speedometer identification has been researched for many years.The common approaches to that problem are usually based on image subtraction,which does not adapt to image offsets caused by camera vibration.To cope with ...Speedometer identification has been researched for many years.The common approaches to that problem are usually based on image subtraction,which does not adapt to image offsets caused by camera vibration.To cope with the rapidity,robust and accurate requirements of this kind of work in dynamic scene,a fast speedometer identification algorithm is proposed,it utilizes phase correlation method based on regional entire template translation to estimate the offset between images.In order to effectively reduce unnecessary computation and false detection rate,an improved linear Hough transform method with two optimization strategies is presented for pointer line detection.Based on VC++ 6.0 software platform with OpenCV library,the algorithm performance under experiments has shown that it celerity and precision.展开更多
This paper presents a study on the statistical forecasts of typhoon tracks. Numerical models have their own systematic errors, like a bias. In order to improve the accuracy of track forecasting, a statistical model ca...This paper presents a study on the statistical forecasts of typhoon tracks. Numerical models have their own systematic errors, like a bias. In order to improve the accuracy of track forecasting, a statistical model called DLM (dynamic linear model) is applied to remove the systematic error. In the analysis of typhoons occurring over the western North Pacific in 1997 and 2000, DLM is useful as an adaptive model for the prediction of typhoon tracks.展开更多
In this paper,a dynamic linear detecting method,that the non-linear coefficient NL% was led and the non-linearity of data were estimated continuously and dynamically and determined when NL% exceeded reference value (...In this paper,a dynamic linear detecting method,that the non-linear coefficient NL% was led and the non-linearity of data were estimated continuously and dynamically and determined when NL% exceeded reference value (5%),was used for data processing and could solve the problem caused by the phenomenon of substrate depleting occurred following the redox reaction in portable blood sugar analyzer.By contrast to the conventional end-point method,the dynamic linear detecting method is based on multipoint data collecting.Experiments of measuring the calibration glucose solution with 8 various concentrations from 50 mg/dl to 400 mg/dl were carried out with the analyzer developed by our group.The linear regression curve,whose correlation for the data was 0.9995 and the residual was 2.8080,were obtained.The obtained correlation,residual, and the computation workload are all fit for the portable blood sugar analyzer.展开更多
We theoretically and numerically study the propagation dynamics of a Gaussian beam modeled by the fractional Schrodinger equation with different dynamic linear potentials. For the limited case α = 1(α is the Lé...We theoretically and numerically study the propagation dynamics of a Gaussian beam modeled by the fractional Schrodinger equation with different dynamic linear potentials. For the limited case α = 1(α is the Lévy index) in the momentum space, the beam suffers a frequency shift which depends on the applied longitudinal modulation and the involved chirp. While in the real space, by precisely controlling the linear chirp, the beam will exhibit two different evolution characteristics: one is the zigzag trajectory propagation induced by multi-reflection occurring at the zeros of spatial spectrum,the other is diffraction-free propagation. Numerical simulations are in full accordance with the theoretical results. Increase of the Lévy index not only results in the drift of those turning points along the transverse direction, but also leads to the delocalization of the Gaussian beam.展开更多
This paper applied the theory and method of non linear dynamic to study the integrated environ economic system( EES ). The results of the numerical computational experiment and theoretical inductions showed that the...This paper applied the theory and method of non linear dynamic to study the integrated environ economic system( EES ). The results of the numerical computational experiment and theoretical inductions showed that the system behaviour pattern of the EES will be changed with the variation of the force power level. When the force DP become higher, the system loss its stability gradually, until the chaos occurs. Based on these results, this paper presented an explanation for the long wave economic fluctuation, and proposed in order to guarantee the sustainable development of the specific EES, the DP value of the system should be limited within a reasonable range.展开更多
This paper aims to study robust impulsive synchronization problem foruncertain linear discrete dynamical network. For the discrete dynamical networks with unknown butbounded linear coupling, by introducing the concept...This paper aims to study robust impulsive synchronization problem foruncertain linear discrete dynamical network. For the discrete dynamical networks with unknown butbounded linear coupling, by introducing the concept of uniformly positive definite matrix functions,some robust impulsive controllers are designed, which ensure that the state of a discrete dynamicalnetwork globally asymptotically synchronizes with an arbitrarily assigned state of an isolate nodeof the network. This paper also investigates the synchronization problem where the network couplingfunctions are uncertain but bounded nonlinear functions. Finally, two examples are simulated toillustrate our results.展开更多
The experimental random error and desired valuse of non observed points in dynamic indexes were estimated by establishing the linear regression equations about variety regulations of dynamic indexes.The methods for d...The experimental random error and desired valuse of non observed points in dynamic indexes were estimated by establishing the linear regression equations about variety regulations of dynamic indexes.The methods for difference significant test among different treatments using dynamic point as indexes were presented without setting the replication on each dynamic point observed.展开更多
The use of functions, expressible in terms of Lucas polynomials of the second kind, allows us to write down the solution of linear dynamical systems—both in the discrete and continuous case—avoiding the Jordan...The use of functions, expressible in terms of Lucas polynomials of the second kind, allows us to write down the solution of linear dynamical systems—both in the discrete and continuous case—avoiding the Jordan canonical form of involved matrices. This improves the computational complexity of the algorithms used in literature.展开更多
In this article,an effective technique is developed to efficiently obtain the output responses of parameterized structural dynamic problems.This technique is based on the conception of reduced basis method and the usa...In this article,an effective technique is developed to efficiently obtain the output responses of parameterized structural dynamic problems.This technique is based on the conception of reduced basis method and the usage of linear interpolation principle.The original problem is projected onto the reduced basis space by linear interpolation projection,and subsequently an associated interpolation matrix is generated.To ensure the largest nonsingularity,the interpolation matrix needs to go through a timenode choosing process,which is developed by applying the angle of vector spaces.As a part of this technique,error estimation is recommended for achieving the computational error bound.To ensure the successful performance of this technique,the offline-online computational procedures are conducted in practical engineering.Two numerical examples demonstrate the accuracy and efficiency of the presented method.展开更多
The perovskite photodetectors can be used for image sensing, environmental monitoring, optical communication, and chemical/biological detection. In the recent five years, the perovskite photoelectric detectors with va...The perovskite photodetectors can be used for image sensing, environmental monitoring, optical communication, and chemical/biological detection. In the recent five years, the perovskite photoelectric detectors with various devices are welldesigned and have made unprecedented progress of light detection. It is necessary to emphasize the most interesting works and summarize them to provide researchers with systematic information. In this review, we report the recent progress in perovskite photodetectors, including highly sensitive, ultrafast response speed, high gain, low noise, flexibility, and narrowband, concentrating on the photodetection performance of versatile halide perovskites(organic–inorganic hybrid and all inorganic compositions). Currently, organic–inorganic hybrid and all-inorganic halide microcrystals with polycrystalline film, nanoparticle/wire/chip, and block monocrystalline morphology control show important performance in response rate,decomposition rate, noise equivalent power, linear dynamic range, and response speed. It is expected that a comprehensive compendium of the research status of perovskite photodetectors will contribute to the development of this area.展开更多
For a type of high⁃order discrete⁃time nonlinear systems(HDNS)whose system models are undefined,a model⁃free predictive control(MFPC)algorithm is proposed in this paper.At first,an estimation model is given by the imp...For a type of high⁃order discrete⁃time nonlinear systems(HDNS)whose system models are undefined,a model⁃free predictive control(MFPC)algorithm is proposed in this paper.At first,an estimation model is given by the improved projection algorithm to approach the controlled nonlinear system.Then,on the basis of the estimation model,a predictive controller is designed by solving the finite time domain rolling optimization quadratic function,and the controller’s explicit analytic solution is also obtained.Furthermore,the closed⁃loop system's stability can be ensured.Finally,the results of simulation reveal that the presented control strategy has a faster convergence speed as well as more stable dynamic property compared with the model⁃free sliding mode control(MFSC).展开更多
This article presented a new data fusion approach for reasonably predicting dynamic serviceability reliability of the long-span bridge girder.Firstly,multivariate Bayesian dynamic linear model(MBDLM)considering dynami...This article presented a new data fusion approach for reasonably predicting dynamic serviceability reliability of the long-span bridge girder.Firstly,multivariate Bayesian dynamic linear model(MBDLM)considering dynamic correlation among the multiple variables is provided to predict dynamic extreme deflections;secondly,with the proposed MBDLM,the dynamic correlation coefficients between any two performance functions can be predicted;finally,based on MBDLM and Gaussian copula technique,a new data fusion method is given to predict the serviceability reliability of the long-span bridge girder,and the monitoring extreme deflection data from an actual bridge is provided to illustrated the feasibility and application of the proposed method.展开更多
The dynamic linear state feedback control problem is addressed for a class of nonlinear systems subject to time-delay.First,using the dynamic change of coordinates,the problem of global state feedback stabilization is...The dynamic linear state feedback control problem is addressed for a class of nonlinear systems subject to time-delay.First,using the dynamic change of coordinates,the problem of global state feedback stabilization is solved for a class of time-delay systems under a type of nonhomogeneous growth conditions.With the aid of an appropriate Lyapunov-Krasovskii functional and the adaptive strategy used in coordinates,the closed-loop system can be globally asymptotically stabilized by the dynamic linear state feedback controller.The growth condition in perturbations are more general than that in the existing results.The correctness of the theoretical results are illustrated with an academic simulation example.展开更多
This study presents a CMOS receiver chip realized in 0.18μm standard CMOS technology and in- tended for high precision 3-D laser radar. The chip includes an adjustable gain transimpedance pre-amplifier, a post-amplif...This study presents a CMOS receiver chip realized in 0.18μm standard CMOS technology and in- tended for high precision 3-D laser radar. The chip includes an adjustable gain transimpedance pre-amplifier, a post-amplifier and two timing comparators. An additional feedback is employed in the regulated cascode tran- simpedance amplifier to decrease the input impedance, and a variable gain transimpedance amplifier controlled by digital switches and analog multiplexer is utilized to realize four gain modes, extending the input dynamic range. The measurement shows that the highest transimpedance of the channel is 50 kΩ, the uncompensated walk error is 1.44 ns in a wide linear dynamic range of 66 dB (1 : 2000), and the input referred noise current is 2.3 pA/√ (rms), resulting in a very low detectable input current of 1μA with SNR = 5.展开更多
We propose a new functional single index model, which called dynamic single-index model for functional data, or DSIM, to efficiently perform non-linear and dynamic relationships between functional predictor and functi...We propose a new functional single index model, which called dynamic single-index model for functional data, or DSIM, to efficiently perform non-linear and dynamic relationships between functional predictor and functional response. The proposed model naturally allows for some curvature not captured by the ordinary functional linear model. By using the proposed two-step estimating algorithm, we develop the estimates for both the link function and the regression coefficient function, and then provide predictions of new response trajectories. Besides the asymptotic properties for the estimates of the unknown functions, we also establish the consistency of the predictions of new response trajectories under mild conditions. Finally, we show through extensive simulation studies and a real data example that the proposed DSIM can highly outperform existed functional regression methods in most settings.展开更多
In this paper,a novel formation control strategy is proposed to address the target tracking and circumnavigating problem of multi-UAV formation.First,two sets of definitions,space angle definition and space vector def...In this paper,a novel formation control strategy is proposed to address the target tracking and circumnavigating problem of multi-UAV formation.First,two sets of definitions,space angle definition and space vector definition,are presented in order to describe the flight state and construct the desired relative velocity.Then,the relative kinematic model between the UAV and the moving target is established.The distributed control law is constructed by using dynamic feedback linearization so as to realize the tracking and circumnavigating control with the desired velocity,circing radius and relative angular spacing.Next,the exponential stability of the closed-loop system is further guaranteed by properly choosing some corresponding parameters based on the Lyapunov method.Finally,the numerical simulation is caried out to verify the effectiveness of the proposed control method.展开更多
文摘Non-linear dynamics,fractals,periodic oscillations,bifurcations,chaos,and other terminologies have been used to describe human biological systems in the literature for a few decades.The eight manuscripts included in this special issue discussed the historical background,
文摘The 3-hour-interval prediction of ground-level temperature from +00 h out to +45 h in South Korea (38 stations) is performed using the DLM (dynamic linear model) in order to eliminate the systematic error of numerical model forecasts. Numerical model forecasts and observations are used as input values of the DLM. According to the comparison of the DLM forecasts to the KFM (Kalman filter model) forecasts with RMSE and bias, the DLM is useful to improve the accuracy of prediction.
文摘This paper deals with the Hyers-Ulam stability of the nonhomogeneous linear dynamic equation x~?(t)-ax(t) = f(t), where a ∈ R^+. The main results can be regarded as a supplement of the stability results of the corresponding homogeneous linear dynamic equation obtained by Anderson and Onitsuka(Anderson D R, Onitsuka M. Hyers-Ulam stability of first-order homogeneous linear dynamic equations on time scales. Demonstratio Math., 2018, 51: 198–210).
基金National Natural Science Foundation of China(Nos.11671258 and 11371086)。
文摘A finite dynamical system(FDS)over a lattice L is a pair(S(L),f),where S(L)is a left-L module and f is a mapping from S into itself.The phase space of(S(L),f)is a digraph whose vertex set is S(L)and there is an arc from x to y if y=f(x).Let L be a finite distributive lattice,A an n×n matrix over L,and f(x)=Ax.The structure of the phase space of the FDS(Ln,f)is discussed.The number of limit cycles in the phase space of(Ln,f)is described in Möbius function.The phase spaces of some invertible,nilpotent,and idempotent FDS(Ln,f)are characterized explicitly.
基金Supported by the National Natural Science Foundation of China (61004139)Beijing Municipal Natural Science Foundation(4101001)2008 Yangtze Fund Scholar and Innovative Research Team Development Schemes of Ministry of Education
文摘Speedometer identification has been researched for many years.The common approaches to that problem are usually based on image subtraction,which does not adapt to image offsets caused by camera vibration.To cope with the rapidity,robust and accurate requirements of this kind of work in dynamic scene,a fast speedometer identification algorithm is proposed,it utilizes phase correlation method based on regional entire template translation to estimate the offset between images.In order to effectively reduce unnecessary computation and false detection rate,an improved linear Hough transform method with two optimization strategies is presented for pointer line detection.Based on VC++ 6.0 software platform with OpenCV library,the algorithm performance under experiments has shown that it celerity and precision.
基金the project"A study on improving forecast skill using a su-percomputer"of Meteorological Research Institute,KMA,2001.
文摘This paper presents a study on the statistical forecasts of typhoon tracks. Numerical models have their own systematic errors, like a bias. In order to improve the accuracy of track forecasting, a statistical model called DLM (dynamic linear model) is applied to remove the systematic error. In the analysis of typhoons occurring over the western North Pacific in 1997 and 2000, DLM is useful as an adaptive model for the prediction of typhoon tracks.
文摘In this paper,a dynamic linear detecting method,that the non-linear coefficient NL% was led and the non-linearity of data were estimated continuously and dynamically and determined when NL% exceeded reference value (5%),was used for data processing and could solve the problem caused by the phenomenon of substrate depleting occurred following the redox reaction in portable blood sugar analyzer.By contrast to the conventional end-point method,the dynamic linear detecting method is based on multipoint data collecting.Experiments of measuring the calibration glucose solution with 8 various concentrations from 50 mg/dl to 400 mg/dl were carried out with the analyzer developed by our group.The linear regression curve,whose correlation for the data was 0.9995 and the residual was 2.8080,were obtained.The obtained correlation,residual, and the computation workload are all fit for the portable blood sugar analyzer.
基金Project supported by the Natural Science Research Project of Anhui Provincal Education Department of China(Grant Nos.KJHS2018B01 and KJ2018A0407)the National Natural Science Foundation of China(Grant No.11804112)+1 种基金the Natural Science Foundation of Anhui Province of China(Grant No.1808085QA22)Start-up Fund of Huangshan University,China(Grant No.2015xkjq001).
文摘We theoretically and numerically study the propagation dynamics of a Gaussian beam modeled by the fractional Schrodinger equation with different dynamic linear potentials. For the limited case α = 1(α is the Lévy index) in the momentum space, the beam suffers a frequency shift which depends on the applied longitudinal modulation and the involved chirp. While in the real space, by precisely controlling the linear chirp, the beam will exhibit two different evolution characteristics: one is the zigzag trajectory propagation induced by multi-reflection occurring at the zeros of spatial spectrum,the other is diffraction-free propagation. Numerical simulations are in full accordance with the theoretical results. Increase of the Lévy index not only results in the drift of those turning points along the transverse direction, but also leads to the delocalization of the Gaussian beam.
文摘This paper applied the theory and method of non linear dynamic to study the integrated environ economic system( EES ). The results of the numerical computational experiment and theoretical inductions showed that the system behaviour pattern of the EES will be changed with the variation of the force power level. When the force DP become higher, the system loss its stability gradually, until the chaos occurs. Based on these results, this paper presented an explanation for the long wave economic fluctuation, and proposed in order to guarantee the sustainable development of the specific EES, the DP value of the system should be limited within a reasonable range.
文摘This paper aims to study robust impulsive synchronization problem foruncertain linear discrete dynamical network. For the discrete dynamical networks with unknown butbounded linear coupling, by introducing the concept of uniformly positive definite matrix functions,some robust impulsive controllers are designed, which ensure that the state of a discrete dynamicalnetwork globally asymptotically synchronizes with an arbitrarily assigned state of an isolate nodeof the network. This paper also investigates the synchronization problem where the network couplingfunctions are uncertain but bounded nonlinear functions. Finally, two examples are simulated toillustrate our results.
文摘The experimental random error and desired valuse of non observed points in dynamic indexes were estimated by establishing the linear regression equations about variety regulations of dynamic indexes.The methods for difference significant test among different treatments using dynamic point as indexes were presented without setting the replication on each dynamic point observed.
文摘The use of functions, expressible in terms of Lucas polynomials of the second kind, allows us to write down the solution of linear dynamical systems—both in the discrete and continuous case—avoiding the Jordan canonical form of involved matrices. This improves the computational complexity of the algorithms used in literature.
基金supported by the National Natural Science Foundation of China (10802028)the Major State Basic Research Development Program of China (2010CB832705)the National Science Fund for Distinguished Young Scholars (10725208)
文摘In this article,an effective technique is developed to efficiently obtain the output responses of parameterized structural dynamic problems.This technique is based on the conception of reduced basis method and the usage of linear interpolation principle.The original problem is projected onto the reduced basis space by linear interpolation projection,and subsequently an associated interpolation matrix is generated.To ensure the largest nonsingularity,the interpolation matrix needs to go through a timenode choosing process,which is developed by applying the angle of vector spaces.As a part of this technique,error estimation is recommended for achieving the computational error bound.To ensure the successful performance of this technique,the offline-online computational procedures are conducted in practical engineering.Two numerical examples demonstrate the accuracy and efficiency of the presented method.
基金Project supported by the International Cooperation and Exchange Project of Jilin Province,China(Grant Nos.20170414002GH and 20180414001GH)
文摘The perovskite photodetectors can be used for image sensing, environmental monitoring, optical communication, and chemical/biological detection. In the recent five years, the perovskite photoelectric detectors with various devices are welldesigned and have made unprecedented progress of light detection. It is necessary to emphasize the most interesting works and summarize them to provide researchers with systematic information. In this review, we report the recent progress in perovskite photodetectors, including highly sensitive, ultrafast response speed, high gain, low noise, flexibility, and narrowband, concentrating on the photodetection performance of versatile halide perovskites(organic–inorganic hybrid and all inorganic compositions). Currently, organic–inorganic hybrid and all-inorganic halide microcrystals with polycrystalline film, nanoparticle/wire/chip, and block monocrystalline morphology control show important performance in response rate,decomposition rate, noise equivalent power, linear dynamic range, and response speed. It is expected that a comprehensive compendium of the research status of perovskite photodetectors will contribute to the development of this area.
基金Sponsored by the National Natural Science Foundation of China(Grant No.61803224)the Natural Science Foundation of Shandong Province(Grant No.ZR2019QF005).
文摘For a type of high⁃order discrete⁃time nonlinear systems(HDNS)whose system models are undefined,a model⁃free predictive control(MFPC)algorithm is proposed in this paper.At first,an estimation model is given by the improved projection algorithm to approach the controlled nonlinear system.Then,on the basis of the estimation model,a predictive controller is designed by solving the finite time domain rolling optimization quadratic function,and the controller’s explicit analytic solution is also obtained.Furthermore,the closed⁃loop system's stability can be ensured.Finally,the results of simulation reveal that the presented control strategy has a faster convergence speed as well as more stable dynamic property compared with the model⁃free sliding mode control(MFSC).
基金This work was supported by Natural Science Foundation of Gansu Province of China(20JR10RA625,20JR10RA623)National Key Research and Development Project of China(Project No.2019YFC1511005)+1 种基金Fundamental Research Funds for the Central Universities(Grant No.lzujbky-2020-55)National Natural Science Foundation of China(Grant No.51608243).
文摘This article presented a new data fusion approach for reasonably predicting dynamic serviceability reliability of the long-span bridge girder.Firstly,multivariate Bayesian dynamic linear model(MBDLM)considering dynamic correlation among the multiple variables is provided to predict dynamic extreme deflections;secondly,with the proposed MBDLM,the dynamic correlation coefficients between any two performance functions can be predicted;finally,based on MBDLM and Gaussian copula technique,a new data fusion method is given to predict the serviceability reliability of the long-span bridge girder,and the monitoring extreme deflection data from an actual bridge is provided to illustrated the feasibility and application of the proposed method.
基金supported by US National Science Foundation under Grant No.HRD-0932339the National Natural Science Foundation of China under Grant Nos.61374038,61374050,61273119,61174076+1 种基金the Natural Science Foundation of Jiangsu Province of China under Grant No.BK2011253Research Fund for the Doctoral Program of Higher Education of China under Grant No.20110092110021
文摘The dynamic linear state feedback control problem is addressed for a class of nonlinear systems subject to time-delay.First,using the dynamic change of coordinates,the problem of global state feedback stabilization is solved for a class of time-delay systems under a type of nonhomogeneous growth conditions.With the aid of an appropriate Lyapunov-Krasovskii functional and the adaptive strategy used in coordinates,the closed-loop system can be globally asymptotically stabilized by the dynamic linear state feedback controller.The growth condition in perturbations are more general than that in the existing results.The correctness of the theoretical results are illustrated with an academic simulation example.
文摘This study presents a CMOS receiver chip realized in 0.18μm standard CMOS technology and in- tended for high precision 3-D laser radar. The chip includes an adjustable gain transimpedance pre-amplifier, a post-amplifier and two timing comparators. An additional feedback is employed in the regulated cascode tran- simpedance amplifier to decrease the input impedance, and a variable gain transimpedance amplifier controlled by digital switches and analog multiplexer is utilized to realize four gain modes, extending the input dynamic range. The measurement shows that the highest transimpedance of the channel is 50 kΩ, the uncompensated walk error is 1.44 ns in a wide linear dynamic range of 66 dB (1 : 2000), and the input referred noise current is 2.3 pA/√ (rms), resulting in a very low detectable input current of 1μA with SNR = 5.
基金supported by National Natural Science Foundation of China (Grant No. 11271080)
文摘We propose a new functional single index model, which called dynamic single-index model for functional data, or DSIM, to efficiently perform non-linear and dynamic relationships between functional predictor and functional response. The proposed model naturally allows for some curvature not captured by the ordinary functional linear model. By using the proposed two-step estimating algorithm, we develop the estimates for both the link function and the regression coefficient function, and then provide predictions of new response trajectories. Besides the asymptotic properties for the estimates of the unknown functions, we also establish the consistency of the predictions of new response trajectories under mild conditions. Finally, we show through extensive simulation studies and a real data example that the proposed DSIM can highly outperform existed functional regression methods in most settings.
基金supported in part by the National Natural Science Foundation of China(61703081,62173082)the Liaoning Joint Fund of National Natural Science Foundation of China(U1908217)+2 种基金the Liaoning Revitalization Talents Program(XLYC1801005)Natural Science Foundation of Liaoning Province(20170520113)and the Fundamental Research Funds for the Central Universities(N2004016).
文摘In this paper,a novel formation control strategy is proposed to address the target tracking and circumnavigating problem of multi-UAV formation.First,two sets of definitions,space angle definition and space vector definition,are presented in order to describe the flight state and construct the desired relative velocity.Then,the relative kinematic model between the UAV and the moving target is established.The distributed control law is constructed by using dynamic feedback linearization so as to realize the tracking and circumnavigating control with the desired velocity,circing radius and relative angular spacing.Next,the exponential stability of the closed-loop system is further guaranteed by properly choosing some corresponding parameters based on the Lyapunov method.Finally,the numerical simulation is caried out to verify the effectiveness of the proposed control method.