CAJ | 학술논문

实测光谱常含有大量干扰信息，消噪在光谱数据处理和分析中极为重要，它直接影响后续的定量分析和信息挖掘。因此，选择适当的消噪方法是改善光谱分析精度，提升光谱分析能力的一个关键性突破。集合经验模态分解（EEMD）方法是一个以信号固有特征尺度为度量的时空滤波过程，能充分保留信号本身的非线性和非平稳特征，在信号的滤波和消噪中具有较大的优势。结合EEMD的多尺度滤波特性，提出了一种新的EEMD阈值光谱消噪方法，并应用于新疆塔里木河中游典型绿洲33个土壤剖面反射光谱数据的预处理。为探讨EEMD阈值法在土壤剖面反射光谱消噪中的效用，对EEMD阈值法和小波阈值法的消噪结果进行了对比分析。结果表明：与传统的小波阈值法相比，EEMD阈值法消噪结果的信噪比从14.8366 dB提高到34.2757 dB ，均方根误差由6.7861×10－5降到7.2406×10－6，相关系数从0.9825提高到0.9998， EEMD阈值法的三个消噪效果衡量指标均优于小波阈值法。证明了EEMD阈值法可有效地去除土壤剖面光谱噪声，较好地保留了光谱的细节信息，提高了光谱的定量分析精度，且与小波阈值消噪方法相比具有较强的可靠性和自适应优势，作为光谱数据预处理的一种新方法，其应用前景良好。
실측광보상함유대량간우신식，소조재광보수거처리화분석중겁위중요，타직접영향후속적정량분석화신식알굴。인차，선택괄당적소조방법시개선광보분석정도，제승광보분석능력적일개관건성돌파。집합경험모태분해（EEMD）방법시일개이신호고유특정척도위도량적시공려파과정，능충분보류신호본신적비선성화비평은특정，재신호적려파화소조중구유교대적우세。결합EEMD적다척도려파특성，제출료일충신적EEMD역치광보소조방법，병응용우신강탑리목하중유전형록주33개토양부면반사광보수거적예처리。위탐토EEMD역치법재토양부면반사광보소조중적효용，대EEMD역치법화소파역치법적소조결과진행료대비분석。결과표명：여전통적소파역치법상비，EEMD역치법소조결과적신조비종14.8366 dB제고도34.2757 dB ，균방근오차유6.7861×10－5강도7.2406×10－6，상관계수종0.9825제고도0.9998， EEMD역치법적삼개소조효과형량지표균우우소파역치법。증명료EEMD역치법가유효지거제토양부면광보조성，교호지보류료광보적세절신식，제고료광보적정량분석정도，차여소파역치소조방법상비구유교강적가고성화자괄응우세，작위광보수거예처리적일충신방법，기응용전경량호。
In the present paper ,based on the multi-resolution attribute of EEMD (ensemble empirical mode decomposition ) method ,we presented a new de-noising method for analyzing spectrum ,and applied it to process the reflecting spectrum data of 33 soil profiles in the typical oasis located in the middle reaches of the Tarim River .To explore the de-noising effect of EEMD threshold method for reflecting spectrum in soil profiles ,we compared EEMD threshold method with wavelet transform method . The results showed that compared with traditional wavelet transform method ,the signal to noise ratio (SNR) was improved from 14.836 6 to 34.275 7 dB ,and the root mean square error (RMSE) was reduced to 7.240 6 × 10-6 from 6.786 1 × 10-5 and the correlation coefficient (r) increased from 0.982 5 to 0.999 8 .Therefore ,three de-noising effect indicators of EEMD thresh-old method are better than those of wavelet transform method .This proved that the EEMD threshold method can effectively eliminate the noise of soil-profile spectrum and also preserve the detailed information of the original spectra well .Thus ,the anal-ysis precision of the spectrum will be improved .In addition ,by contrast with the wavelet threshold method ,the EEMD thresh-old method is adaptive and is fairly reliable .As a new method for spectral pretreatment ,the EEMD threshold method will have a good application prospect in spectra de-noising .