Application of Wavelength Selection Combined with DS Algorithm for Model Transfer between NIR Instruments

This study aims to realize the sharing of near-infrared analysis models of lignin and holocellulose content in pulp wood on two different batches of spectrometers and proposes a combined algorithm of SPA-DS,MCUVE-DS and SiPLS-DS.The Successive Projection Algorithm(SPA),the Monte-Carlo of Uninformative Variable Elimination(MCUVE)and the Synergy Interval Partial Least Squares(SiPLS)algorithms are respectively used to reduce the adverse effects of redundant information in the transmission process of the full spectrum DS algorithm model.These three algorithms can improve model transfer accuracy and efficiency and reduce the manpower and material consumption required for modeling.These results show that the modeling effects of the characteristic wavelengths screened by the SPA,MCUVE and SiPLS algorithms are all greatly improved compared with the full-spectrum modeling,in which the SPA-PLS result in the best prediction with RPDs above 6.5 for both components.The three wavelength selection methods combined with the DS algorithm are used to transfer the models of the two instruments.Among them,the MCUVE combined with the DS algorithm has the best transfer effect.After the model transfer,the RMSEP of lignin is 0.701,and the RMSEP of holocellulose is 0.839,which was improved significantly than the full-spectrum model transfer of 0.759 and 0.918.

An Ant Colony Algorithm Based on Cross-Layer Design for Routing and Wavelength Assignment in Optical Satellite Networks

This paper introduces an ant colony routing and wavelength assignment algorithm based on cross-layer design(CL-ACRWA),which can overcome the adverse effects of Doppler wavelength shift on data transmission in optical satellite networks. Firstly, a cross-layer optimization model is built, which considers the Doppler wavelength shift, the transmission delay as well as wavelength-continuity constraint. Then an ant colony algorithm is utilized to solve the cross-layer optimization model, resulting in finding an optimal light path satisfying the above constraints for every connection request. The performance of CL-ACRWA is measured by the communication success probability, the convergence property and the transmission delay. Simulation results show that CL-ACRWA performs well in communication success probability and has good global search ability as well as fast convergence speed. Meanwhile, the transmission delay can meet the basic requirement of real-time transmission of business.

Rapid and simultaneous analysis of multiple wine quality indicators through near-infrared spectroscopy with twice optimization for wavelength model

Alcohol,total sugar,total acid,and total phenol contents are the main indicators of wine quality detection.This study aims to establish simultaneous analysis models for the four indicators through near-infrared(NIR)spectroscopy with wavelength optimization.A Norris derivative filter(NDF)platform with multiparameter optimization was established for spectral pretreatment.The optimal parameters(i.e.,derivative order,number of smoothing points,and number of differential gaps)were(2,9,3)for alcohol,(1,19,5)for total sugar,(1,17,11)for total acid,and(1,1,1)for total phenol.The equidistant combinationpartial least squares(EC-PLS)was used for large-scale wavelength screening.The wavelength step-by-step phaseout PLS(WSP-PLS)and exhaustive methods were used for secondary optimization.The final optimization models for the four indicators included 7,10,15,and 13 wavelengths located in the overtone or combination regions,respectively.In an independent validation,the root mean square errors,correlation coefficient for prediction(i.e.,SEP and RP),and ratio of performance-to-deviation(RPD)were 0.41 v/v,0.947,and 3.2 for alcohol;1.48 g/L,0.992,and 6.8 for total sugar;0.68 g/L,0.981,and5.1 for total acid;and 0.181 g/L,0.948,and 2.9 for total phenol.The results indicate high correlation,low error,and good overall prediction performance.Consequently,the established reagent-free NIR analytical models are important in the rapid and real-time quality detection of the wine fermentation process and finished products.The proposed wavelength models provide a valuable reference for designing small dedicated instruments.

Matched-Cladding Single-Mode Optical Fiber Optimized at 850 nm Wavelength

A single-mode optical fiber with quadratic curve index profile in core layer is introduced. The profile is optimized at 850 ran wavelength. The 850 nm bandwidth of this fiber can reach up to 2056.35 MHz.km. This fiber can be used at 850 nm, 1310 nm, and 1550 nm wavelength.