The size-dependent growth of dexamethasone sodium phosphate was studied in a MSMPR crystallizer. The Bransom,CR,ASL,MJ2 and MJ3 size-dependent growth rate models were discussed in details. Using experimental steady st...The size-dependent growth of dexamethasone sodium phosphate was studied in a MSMPR crystallizer. The Bransom,CR,ASL,MJ2 and MJ3 size-dependent growth rate models were discussed in details. Using experimental steady state population density data of dexamethasone sodium phosphate, the parameters of five size-dependent growth rate models were determined by the non-linear least-squares method. By comparison of experimental population density data and linear growth rate data with those calculated from five size-dependent growth rate models, it was found that the MJ3 model was the best one for predicting the growth of dexamethasone sodium phosphate.展开更多
A hybrid compensation scheme for piezoelectric ceramic actuators(PEAs)is proposed.In the hybrid compensation scheme,the input rate-dependent hysteresis characteristics of the PEAs are compensated.The feedforward contr...A hybrid compensation scheme for piezoelectric ceramic actuators(PEAs)is proposed.In the hybrid compensation scheme,the input rate-dependent hysteresis characteristics of the PEAs are compensated.The feedforward controller is a novel input rate-dependent neural network hysteresis inverse model,while the feedback controller is a proportion integration differentiation(PID)controller.In the proposed inverse model,an input ratedependent auxiliary inverse operator(RAIO)and output of the hysteresis construct the expanded input space(EIS)of the inverse model which transforms the hysteresis inverse with multi-valued mapping into single-valued mapping,and the wiping-out,rate-dependent and continuous properties of the RAIO are analyzed in theories.Based on the EIS method,a hysteresis neural network inverse model,namely the dynamic back propagation neural network(DBPNN)model,is established.Moreover,a hybrid compensation scheme for the PEAs is designed to compensate for the hysteresis.Finally,the proposed method,the conventional PID controller and the hybrid controller with the modified input rate-dependent Prandtl-Ishlinskii(MRPI)model are all applied in the experimental platform.Experimental results show that the proposed method has obvious superiorities in the performance of the system.展开更多
A wavelet-based spectral correlation algorithm to detect and estimate BPSK signal chip rate is proposed. Simulation results show that the proposed method can correctly estimate the BPSK signal chip rate, which may be ...A wavelet-based spectral correlation algorithm to detect and estimate BPSK signal chip rate is proposed. Simulation results show that the proposed method can correctly estimate the BPSK signal chip rate, which may be corrupted by the quadratic characteristics of the spectral correlation function, in a low SNR environment.展开更多
Rheological behavior of this article presents rapeseed oil. Dynamic viscosity of rapeseed oil was determined at temperatures between 40 ℃-90 ℃ and shear rates ranging from 3.3-120 s1. All types of oils studied Bingh...Rheological behavior of this article presents rapeseed oil. Dynamic viscosity of rapeseed oil was determined at temperatures between 40 ℃-90 ℃ and shear rates ranging from 3.3-120 s1. All types of oils studied Bingham fluid behavior in the temperature range from 313-363 K. Correlation coefficients have similar values to one for all oils studied.展开更多
A rate equation approach was presented for the exact computation of the three vertex degree correlations of the fixed act-size collaboration networks.Measurements of the three vertex degree correlations were based on ...A rate equation approach was presented for the exact computation of the three vertex degree correlations of the fixed act-size collaboration networks.Measurements of the three vertex degree correlations were based on a rate equation in the continuous degree and time approximation for the average degree of the nearest neighbors of vertices of degree k,with an appropriate boundary condition.The rate equation proposed can be generalized in more sophisticated growing network models,and also extended to deal with related correlation measurements.Finally,in order to check the theoretical prediction,a numerical example was solved to demonstrate the performance of the degree correlation function.展开更多
Input selection is probably one of the most critical decision issues in neural network designing, because it has a great impact on forecasting performance. Among the many applications of artificial neural networks to ...Input selection is probably one of the most critical decision issues in neural network designing, because it has a great impact on forecasting performance. Among the many applications of artificial neural networks to finance, time series forecasting is perhaps one of the most challenging issues. Considering the features of neural networks, we propose a general approach called Autocorrelation Criterion (AC) to determine the inputs variables for a neural network. The purpose is to seek optimal lag periods, which are more predictive and less correlated. AC is a data-driven approach in that there is no prior assumptiona bout the models for time series under study. So it has extensive applications and avoids a lengthy experimentation and tinkering in input selection. We apply the approach to the determination of input variables for foreign exchange rate forecasting and conductcomparisons between AC and information-based in-sample model selection criterion. The experiment results show that AC outperforms information-based in-sample model selection criterion.展开更多
Herein we extract all the frequency-dependent coupling-of-modes (COM) parameters, which will be used to the rapid simulation and optimal design of surface acoustic wave (SAW) devices. FEM/BEM is used to calculate ...Herein we extract all the frequency-dependent coupling-of-modes (COM) parameters, which will be used to the rapid simulation and optimal design of surface acoustic wave (SAW) devices. FEM/BEM is used to calculate the exact field distributions of forward and backward surface acoustic waves within a finite-length periodic grating at every frequency. The middle compo- nent of the grating, regarded as a periodic structure, is selected to be investigated which can satisfy the presupposition of the COM model. From these field distributions, the values of P-matrix elements of one cell are calculated. The COM parameters taken as functions of frequency are accurately obtained. Specifically, the frequency-dependent relationships of reflection coefficient and propagation velocity are obtained independently. Using the resultant COM parameters, a one-port resonator on the substrate of 128°YX-LiNbO3 is simulated and the admittance curve shows good agreement with the simulating results using FEM/BEM. These results verify the validity and accuracy of this method.展开更多
A better understanding of nitrogen (N) transformation in agricultural soils is crucial for the development of sustainable and environmental-friendly N fertilizer management and the proposal of effective N20 mitigati...A better understanding of nitrogen (N) transformation in agricultural soils is crucial for the development of sustainable and environmental-friendly N fertilizer management and the proposal of effective N20 mitigation strategies. This study aimed: i) to elucidate the seasonal dynamic of gross nitrification rate and N20 emission, ii) to determine the influence of soil conditions on the gross nitrification, and iii) to confirm the relationship between gross nitrification and N20 emissions in the soil of an apple orchard in Yantai, Northeast China. The gross nitrification rates and N20 fluxes were examined from March to October in 2009, 2010, and 2011 using the barometric process separation (BaPS) technique and the static chamber method. During the wet seasons gross nitrification rates were 1.64 times higher than those under dry season conditions. Multiple regression analysis revealed that gross nitrification rates were significantly correlated with soil temperature and soil water-filled pore space (WFPS). The relationship between gross nitrification rates and soil WFPS followed an optimum curve peaking at 60% WFPS. Nitrous oxide fluxes varied widely from March to October and were stimulated by N fertilizer application. Statistically significant positive correlations were found between gross nitrification rates and soil N20 emissions. Further evaluation indicated that gross nitrification contributed significantly to N20 formation during the dry season (about 86%) but to a lesser degree during the wet season (about 51%). Therefore, gross nitrification is a key process for the formation of N20 in soils of apple orchard ecosystems of the geographical region.展开更多
文摘The size-dependent growth of dexamethasone sodium phosphate was studied in a MSMPR crystallizer. The Bransom,CR,ASL,MJ2 and MJ3 size-dependent growth rate models were discussed in details. Using experimental steady state population density data of dexamethasone sodium phosphate, the parameters of five size-dependent growth rate models were determined by the non-linear least-squares method. By comparison of experimental population density data and linear growth rate data with those calculated from five size-dependent growth rate models, it was found that the MJ3 model was the best one for predicting the growth of dexamethasone sodium phosphate.
基金National Natural Science Foundation of China(Nos.62171285,61971120 and 62327807)。
文摘A hybrid compensation scheme for piezoelectric ceramic actuators(PEAs)is proposed.In the hybrid compensation scheme,the input rate-dependent hysteresis characteristics of the PEAs are compensated.The feedforward controller is a novel input rate-dependent neural network hysteresis inverse model,while the feedback controller is a proportion integration differentiation(PID)controller.In the proposed inverse model,an input ratedependent auxiliary inverse operator(RAIO)and output of the hysteresis construct the expanded input space(EIS)of the inverse model which transforms the hysteresis inverse with multi-valued mapping into single-valued mapping,and the wiping-out,rate-dependent and continuous properties of the RAIO are analyzed in theories.Based on the EIS method,a hysteresis neural network inverse model,namely the dynamic back propagation neural network(DBPNN)model,is established.Moreover,a hybrid compensation scheme for the PEAs is designed to compensate for the hysteresis.Finally,the proposed method,the conventional PID controller and the hybrid controller with the modified input rate-dependent Prandtl-Ishlinskii(MRPI)model are all applied in the experimental platform.Experimental results show that the proposed method has obvious superiorities in the performance of the system.
文摘A wavelet-based spectral correlation algorithm to detect and estimate BPSK signal chip rate is proposed. Simulation results show that the proposed method can correctly estimate the BPSK signal chip rate, which may be corrupted by the quadratic characteristics of the spectral correlation function, in a low SNR environment.
文摘Rheological behavior of this article presents rapeseed oil. Dynamic viscosity of rapeseed oil was determined at temperatures between 40 ℃-90 ℃ and shear rates ranging from 3.3-120 s1. All types of oils studied Bingham fluid behavior in the temperature range from 313-363 K. Correlation coefficients have similar values to one for all oils studied.
基金Project(20090162110058) supported by the Research Fund for the Doctoral Program of Higher Education of ChinaProject(KJ101210) supported by the Foundation of Chongqing Municipal Education Committee,China Project(2009GK3010) supported by the Hunan Science & Technology Foundation,China
文摘A rate equation approach was presented for the exact computation of the three vertex degree correlations of the fixed act-size collaboration networks.Measurements of the three vertex degree correlations were based on a rate equation in the continuous degree and time approximation for the average degree of the nearest neighbors of vertices of degree k,with an appropriate boundary condition.The rate equation proposed can be generalized in more sophisticated growing network models,and also extended to deal with related correlation measurements.Finally,in order to check the theoretical prediction,a numerical example was solved to demonstrate the performance of the degree correlation function.
基金This research is partially supported by Chinese Academy of SciencesNational Science Foundation of ChinaJapan Society for the Promotion of Science.
文摘Input selection is probably one of the most critical decision issues in neural network designing, because it has a great impact on forecasting performance. Among the many applications of artificial neural networks to finance, time series forecasting is perhaps one of the most challenging issues. Considering the features of neural networks, we propose a general approach called Autocorrelation Criterion (AC) to determine the inputs variables for a neural network. The purpose is to seek optimal lag periods, which are more predictive and less correlated. AC is a data-driven approach in that there is no prior assumptiona bout the models for time series under study. So it has extensive applications and avoids a lengthy experimentation and tinkering in input selection. We apply the approach to the determination of input variables for foreign exchange rate forecasting and conductcomparisons between AC and information-based in-sample model selection criterion. The experiment results show that AC outperforms information-based in-sample model selection criterion.
基金supported by the National Natural Science Foundation of China(Grant Nos. 10774073 and 11174143)
文摘Herein we extract all the frequency-dependent coupling-of-modes (COM) parameters, which will be used to the rapid simulation and optimal design of surface acoustic wave (SAW) devices. FEM/BEM is used to calculate the exact field distributions of forward and backward surface acoustic waves within a finite-length periodic grating at every frequency. The middle compo- nent of the grating, regarded as a periodic structure, is selected to be investigated which can satisfy the presupposition of the COM model. From these field distributions, the values of P-matrix elements of one cell are calculated. The COM parameters taken as functions of frequency are accurately obtained. Specifically, the frequency-dependent relationships of reflection coefficient and propagation velocity are obtained independently. Using the resultant COM parameters, a one-port resonator on the substrate of 128°YX-LiNbO3 is simulated and the admittance curve shows good agreement with the simulating results using FEM/BEM. These results verify the validity and accuracy of this method.
基金supported by the Special Fund for Agro-scientific Research in the Public Interest of China (No. 201103003)the Earmarked Fund for China Agriculture Research System (No. CARS-28)
文摘A better understanding of nitrogen (N) transformation in agricultural soils is crucial for the development of sustainable and environmental-friendly N fertilizer management and the proposal of effective N20 mitigation strategies. This study aimed: i) to elucidate the seasonal dynamic of gross nitrification rate and N20 emission, ii) to determine the influence of soil conditions on the gross nitrification, and iii) to confirm the relationship between gross nitrification and N20 emissions in the soil of an apple orchard in Yantai, Northeast China. The gross nitrification rates and N20 fluxes were examined from March to October in 2009, 2010, and 2011 using the barometric process separation (BaPS) technique and the static chamber method. During the wet seasons gross nitrification rates were 1.64 times higher than those under dry season conditions. Multiple regression analysis revealed that gross nitrification rates were significantly correlated with soil temperature and soil water-filled pore space (WFPS). The relationship between gross nitrification rates and soil WFPS followed an optimum curve peaking at 60% WFPS. Nitrous oxide fluxes varied widely from March to October and were stimulated by N fertilizer application. Statistically significant positive correlations were found between gross nitrification rates and soil N20 emissions. Further evaluation indicated that gross nitrification contributed significantly to N20 formation during the dry season (about 86%) but to a lesser degree during the wet season (about 51%). Therefore, gross nitrification is a key process for the formation of N20 in soils of apple orchard ecosystems of the geographical region.