Dissertation > Excellent graduate degree dissertation topics show

Pretreating Near-infrared Spectra by Orthogonal Signal Correction

Author: YuHao
Tutor: ChengYiYuï¼›ZuoHaiBin
School: Zhejiang University
Course: Chemical Engineering
Keywords: Near-infrared spectroscopy orthogonal signal correction multiple chains wavelength selection pretreatment
CLC: O657.33
Type: Master's thesis
Year: 2004
Downloads: 408
Quote: 4
Read: Download Dissertation

Abstract


Analytical applications of Near-Infrared spectroscopy technique have grown dramatically in recent years. It is widely used in lots of areas, such as petrochemical industry, agriculture and food industry, textile industry, pharmaceutics industry and clinical medicine. The wide using of NIR should attribute to the data processing method based on chemometrics. The purpose of this paper focused on pretreatment, one of important steps in the data processing of NIR spectra.Orthogonal signal correction (OSC) is a new popular pretreatment method, and its basic idea is that it removes the parts linearly unrelated (orthogonal) to the response matrix Y from spectral matrix X. In this paper, OSC was applied to preprocess the NIR spectra of herbal medicines. The results show that OSC is suited to preprocess the NIR spectra of herbal medicines. Furthermore, six different algorithms of OSC were compared and the results show that OPLS is the most powerful method of them.The drawback of OSC was discussed in this paper. The noises in the spectra are not absolutely orthogonal to Y, so only the projection on the orthogonal direction to Y can be removed by OSC. The residuals of noises will influence the stability of models and may be a reason of over-fitting. An improvement method is proposed in this paper. Multiple chains method is used for wavelength selection before OSC, and the unrelated points to models are removed for eliminating the interference of noises in some extent. This method is applied to treat the NIR spectra of corn, and the accuracy of calibration model are improved.

Related Dissertations

  1. Research on the Detection of Petechia in Tongue Images,TP391.41
  2. Process and Mechanism of Eucalyptus Pulp Bleaching Catalysed by Cu2+/Co2+,TS745
  3. Cellulose Pretreatment with Ionic Liquid for Enzymatic Hydrolysis,TQ352.1
  4. Monitoring Leaf Nitrogen Status in Rice with Near Infrared Spectroscopy,S511
  5. Based on Rough Set of Urban Areas When Traffic Green Control System Research,TP18
  6. Study of Propylene Oxide Wastewater Pretreatment by Five-effect Evaporation Process,X78
  7. Experimental Study on the Ethylene/air Diffusion Flame Based on Near-infrared Emission Spectrometry Measurement,TK16
  8. Instrument-to-Instrument Calibration Transfer and Standardization of Spectra,O657.33
  9. DSP FPGA -based near-infrared detector key technology research,TN791
  10. Study on Filtering Algorithm of the Aerial Gravity Measurement Data Processing,P223
  11. Research on the Method of Near-infrared Detection of E.coli,R378
  12. Study on Identification of Cashmere and Wool Using Near Infrared Spectroscopy,TS131
  13. Study on Predict the Carcass and Beef Quality of Kerchin Cattle,TS251.52
  14. Study on Rapidly Detecting the Quality of Milk by Near -Inrared Spectroscopy,TS251
  15. The Study of the Separation of Rice Straw Composition and the Fermentation of Its Hydrolyzate to Ethanol,S216.2
  16. Research on Treatment of Micro-polluted Source Water by Slow Biofiltration,TU991.2
  17. Research of Drinking Water Fluoride Removal by Ultra-filtration,TU991.266
  18. Different Frequencies of Electroacupuncture Pretreatment on Rabbit Model of Acute Myocardial Ischemia Comparison of Protective Effect,R245
  19. The Research of the Methods of Detecting Pesticide Residues in Vegetable Based on NIR Technology,TP274
  20. Detection Method and Research for the Quality of Edible Oil Based on Near Infrared Spectroscopy,TN219
  21. Preparation of Zirconia Composite Ultrafiltration Membranes and Application in Seawater Desalination Pretreatment,P747

CLC: > Mathematical sciences and chemical > Chemistry > Analytical Chemistry > Instrument analysis ( physics and physical chemistry ) > Photochemical analysis ( spectral analysis method) > Infrared Spectroscopy
© 2012 www.DissertationTopic.Net  Mobile