The objective of this paper was to study the growth and development laws of Pudong chicken. The growth curve of Pudong chicken （cock and hen） from 0 to 20 weeks was analyzed and fitted with three models（Gompertz, L...The objective of this paper was to study the growth and development laws of Pudong chicken. The growth curve of Pudong chicken （cock and hen） from 0 to 20 weeks was analyzed and fitted with three models（Gompertz, Logistic and Bertalanffy）. It was concluded that the growth curves were appropriately fitted with three models, and fitness degree （R2）in growth data of Pudong chicken were all above 0.992. The Bertalanffy model was the most effective with the highest R2 for cock （R^2=0.995） and hen （R^2=0.999）, respectively. With further analysis of fitted parameters for Logis- tic model of cock, 0-3 weeks＇ fitted values were significantly greater than measured values and 4-8 weeks＇ fitted values were lower than measured values. Compared with Logistic model, the values calculated by Gompertz model and Bertalanffy model were more coincident with the practical measuring values. For hens, 0-3 weeks＇ fitted values of Logistic model were significantly greater than measured values and 0-2 weeks＇ fitted values of Gompertz model were slightly greater than measured values, while the values calculated by Bertalanffy model best matched the observed values from actual measure. The results showed that Bertalanffy model used to estimate the growth weight of Pudong chicken was the best while Logistic model was the worst. So the fitness and analysis of growth curves of Pudong chicken are valid, which may be adopted to predict growth and development laws of Pudong chicken and provide reliable data for precise feeding and breeding.展开更多
Geometric fitting based on discrete points to establish curve structures is an important problem in numerical modeling.The purpose of this paper is to investigate the geometric fitting method for curved beam structure...Geometric fitting based on discrete points to establish curve structures is an important problem in numerical modeling.The purpose of this paper is to investigate the geometric fitting method for curved beam structure from points,and to get high-quality parametric model for isogeometric analysis.ATimoshenko beam element is established for an initially curved spacial beam with arbitrary curvature.The approximation and interpolation methods to get parametric models of curves from given points are examined,and three strategies of parameterization,meaning the equally spaced method,the chord length method and the centripetal method are considered.The influences of the different geometric approximation algorithms on the precision of isogeometric analysis are examined.The static analysis and the modal analysis with the established parametric models are carried out.Three examples with different complexities,the quarter arc curved beam,the Tschirnhausen beam and the Archimedes spiral beam are examined.The results show that for the geometric approximation the interpolation method performs good and maintains high precision.The fitting algorithms are able to provide parametric models for isogeometric analysis of spacial beam with Timoshenko model.The equally spaced method and centripetal method perform better than the chord length method for the algorithm to carry out the parameterization for the sampling points.展开更多
Fourier transform infrared(FTIR)spectroscopy was used to study two kinds of broad beans with white and green cotyledons respectively.The results show that the infrared spectra of the two kinds of broad beans are simil...Fourier transform infrared(FTIR)spectroscopy was used to study two kinds of broad beans with white and green cotyledons respectively.The results show that the infrared spectra of the two kinds of broad beans are similar and mainly made up of the absorption bands of protein,and polysaccharides.The second derivative infrared spectra amplified the differences and revealed that there were some obvious differences in the range of 1 800-700 cm-1and 1 200-700 cm-1.Hierarchical cluster analysis(HCA)were used for the discrimination of the two kinds broad beans based on the second derivative spectral data in the region of 1 611-1 100 cm-1,and yielded 88.9%accuracy.The spectra in the range from 1 700 to 1 600 cm-1were used to perform Fourier self-deconvolution and curve fitting,which obtained nine peaks.The ratios of relative areas of the bands atα-helix,β-sheet,β-turn and the unordered structure of protein in white beans were 67.71%,35.6%,35.6%and 21.09%respectively,while the ratios in green beans were 8.02%,31.59%,37.12%and 23.27%respectively.The results indicate that the secondary structure of protein was different in the two kinds of broad beans.展开更多
A structured perturbation analysis of the least squares problem is considered in this paper.The new error bound proves to be sharper than that for general perturbations. We apply the new error bound to study sensitivi...A structured perturbation analysis of the least squares problem is considered in this paper.The new error bound proves to be sharper than that for general perturbations. We apply the new error bound to study sensitivity of changing the knots for curve fitting of interest rate term structure by cubic spline.Numerical experiments are given to illustrate the sharpness of this bound.展开更多
基金Supported by Seed Industry Project of Science and Technology Promoting Agriculture in Shanghai City(2017 number 2-3)
文摘The objective of this paper was to study the growth and development laws of Pudong chicken. The growth curve of Pudong chicken （cock and hen） from 0 to 20 weeks was analyzed and fitted with three models（Gompertz, Logistic and Bertalanffy）. It was concluded that the growth curves were appropriately fitted with three models, and fitness degree （R2）in growth data of Pudong chicken were all above 0.992. The Bertalanffy model was the most effective with the highest R2 for cock （R^2=0.995） and hen （R^2=0.999）, respectively. With further analysis of fitted parameters for Logis- tic model of cock, 0-3 weeks＇ fitted values were significantly greater than measured values and 4-8 weeks＇ fitted values were lower than measured values. Compared with Logistic model, the values calculated by Gompertz model and Bertalanffy model were more coincident with the practical measuring values. For hens, 0-3 weeks＇ fitted values of Logistic model were significantly greater than measured values and 0-2 weeks＇ fitted values of Gompertz model were slightly greater than measured values, while the values calculated by Bertalanffy model best matched the observed values from actual measure. The results showed that Bertalanffy model used to estimate the growth weight of Pudong chicken was the best while Logistic model was the worst. So the fitness and analysis of growth curves of Pudong chicken are valid, which may be adopted to predict growth and development laws of Pudong chicken and provide reliable data for precise feeding and breeding.
基金This work is funded by the National Key R&D Program of China(Grant No.2018YFA0703200)Project of the National Natural Science Foundation of China(Grant No.11702056)the Fundamental Research Funds for the Central Universities(Grant No.DUT20JC34).
文摘Geometric fitting based on discrete points to establish curve structures is an important problem in numerical modeling.The purpose of this paper is to investigate the geometric fitting method for curved beam structure from points,and to get high-quality parametric model for isogeometric analysis.ATimoshenko beam element is established for an initially curved spacial beam with arbitrary curvature.The approximation and interpolation methods to get parametric models of curves from given points are examined,and three strategies of parameterization,meaning the equally spaced method,the chord length method and the centripetal method are considered.The influences of the different geometric approximation algorithms on the precision of isogeometric analysis are examined.The static analysis and the modal analysis with the established parametric models are carried out.Three examples with different complexities,the quarter arc curved beam,the Tschirnhausen beam and the Archimedes spiral beam are examined.The results show that for the geometric approximation the interpolation method performs good and maintains high precision.The fitting algorithms are able to provide parametric models for isogeometric analysis of spacial beam with Timoshenko model.The equally spaced method and centripetal method perform better than the chord length method for the algorithm to carry out the parameterization for the sampling points.
基金National Natural Science Foundation of China(30960179)
文摘Fourier transform infrared(FTIR)spectroscopy was used to study two kinds of broad beans with white and green cotyledons respectively.The results show that the infrared spectra of the two kinds of broad beans are similar and mainly made up of the absorption bands of protein,and polysaccharides.The second derivative infrared spectra amplified the differences and revealed that there were some obvious differences in the range of 1 800-700 cm-1and 1 200-700 cm-1.Hierarchical cluster analysis(HCA)were used for the discrimination of the two kinds broad beans based on the second derivative spectral data in the region of 1 611-1 100 cm-1,and yielded 88.9%accuracy.The spectra in the range from 1 700 to 1 600 cm-1were used to perform Fourier self-deconvolution and curve fitting,which obtained nine peaks.The ratios of relative areas of the bands atα-helix,β-sheet,β-turn and the unordered structure of protein in white beans were 67.71%,35.6%,35.6%and 21.09%respectively,while the ratios in green beans were 8.02%,31.59%,37.12%and 23.27%respectively.The results indicate that the secondary structure of protein was different in the two kinds of broad beans.
基金Funds for Major State The work of the second author is partly supported by the Special Basic Research Projects （2005CB321700）the National Science Foundation of China under grant No. 10571031The work of the third author is partly supported by the National Science Foundation of China under grant No. 10571031.
文摘A structured perturbation analysis of the least squares problem is considered in this paper.The new error bound proves to be sharper than that for general perturbations. We apply the new error bound to study sensitivity of changing the knots for curve fitting of interest rate term structure by cubic spline.Numerical experiments are given to illustrate the sharpness of this bound.
