ass日本风韵熟妇pics男人扒开女人屁屁桶到爽|扒开胸露出奶头亲吻视频|邻居少妇的诱惑|人人妻在线播放|日日摸夜夜摸狠狠摸婷婷|制服 丝袜 人妻|激情熟妇中文字幕|看黄色欧美特一级|日本av人妻系列|高潮对白av,丰满岳妇乱熟妇之荡,日本丰满熟妇乱又伦,日韩欧美一区二区三区在线

基于嶺回歸的土壤含水率高光譜反演研究
CSTR:
作者:
作者單位:

作者簡介:

通訊作者:

中圖分類號:

基金項目:

國家重點研發(fā)計劃項目(2017YFC0403302,、2016YFD0200700)和楊凌示范區(qū)科技計劃項目(2016NY-26)


Inversion of Soil Moisture Content from Hyperspectra Based on Ridge Regression
Author:
Affiliation:

Fund Project:

  • 摘要
  • |
  • 圖/表
  • |
  • 訪問統(tǒng)計
  • |
  • 參考文獻
  • |
  • 相似文獻
  • |
  • 引證文獻
  • |
  • 資源附件
  • |
  • 文章評論
    摘要:

    以以色列南部Seder Boker地區(qū)采集的粘壤土樣品為研究對象,。在室內利用ASD FieldSpec 3型高光譜儀獲取土壤的原始光譜,在進行數(shù)據(jù)預處理和不同數(shù)學變換后,,共獲取了4種光譜指標:光譜反射率(REF)、倒數(shù)之對數(shù)(LR),、一階微分(FDR)和去包絡線(CR),。采用偏最小二乘回歸法(PLSR)、逐步回歸法(SR)和嶺回歸法(RR)構建了基于不同指標的土壤含水率高光譜反演模型,,并對反演結果進行精度驗證與比較,。結果表明:REF-PLSR模型在所有回歸模型中的反演與預測效果均為最優(yōu)(R2c=0.990,R2p=0.987),,在逐步回歸模型和嶺回歸模型中,,LR-SR(R2c=0.981,R2p=0.971),、LR-RR(R2c=0.975,,R2p=0.979)均為最佳模型,。對于其他3種指標,雖然逐步回歸法和嶺回歸法的建模效果較偏最小二乘回歸法略有下降,,但R2c均大于0.9,,R2p均大于0.8,RPD均大于2.5,,RMSE均小于0.03,,模型仍具有較好的反演效果;逐步回歸法和嶺回歸法均實現(xiàn)了模型的簡化,,但嶺回歸法采用有偏估計從而提高了模型的穩(wěn)健性,,且實現(xiàn)了波段的優(yōu)選(用于建模的波段數(shù)僅為全光譜的03%)。粘壤土土壤含水率LR-RR高光譜反演模型的建立為高光譜模型的優(yōu)化,、土壤含水率的快速測定提供了途徑,。

    Abstract:

    Obtaining soil moisture quickly and timely can grasp the needs of water of the crops, which is very important for the agricultural production. Soil spectral reflectance provides an alternative method to classical physical and chemical analysis of soil in laboratory for the estimation of a large range of key soil properties. Therefore, the soil moisture was quickly achieved by using hyperspectral technology and the application of ridge regression was explored in the optimization and quantitative analysis of hyperspectral bands. Totally 91 soil samples were collected from the soil depth of 0~5cm in Seder Boker area in the southern Israeli. These soil samples were analyzed in the process of physical and chemical properties in laboratory. After that, the raw hyperspectral reflectance of soil samples was measured by an ASD FieldSpec 3 instrument equipped with a high intensity contact probe under the darkroom conditions. Next, the raw spectral reflectance (REF) was transformed to three spectral indices, i.e. inverselog reflectance (LR), the first order differential reflectance (FDR) and continuum removal reflectance (CR). Regression models of soil moisture with different indices were established by three methods: partial least squares regression (PLSR), stepwise regression (SR) and ridge regression (RR). The inversion results of the model were validated and compared with each other. The results showed that the method of LR transform can eliminate the interference of external factors much better, and it appeared to be the optimal spectral index in stepwise regression model and ridge regression model (R2c were 0.981 and 0.975, and R2p were 0.971 and 0.979). For the three spectral indices about REF, FDR and CR, although the modeling effect of SR and RR was slightly lower than that of PLSR, the coefficient of modeling determination was above 0.9. Both SR and RR had simplified and optimized the model, but RR had better validation results and the number of bands used for modeling was only 0.3% of the full spectrum (400~2400Nm). After comparing the three regression models established with the four spectral indices, the LR-RR model not only had the characteristics of simple model and less calculation, but also improved the robustness of the model better by using biased estimation at the cost of losing the part accuracy. The result indicated that ridge regression method can not only achieve the efficient selection of hyperspectral bands, but also use the LR-RR hyperspectral inversion model for the reference of monitoring the aerospace hyperspectral remote sensing of regional soil moisture in the future.

    參考文獻
    相似文獻
    引證文獻
引用本文

張智韜,王海峰,KARNIELI Arnon,陳俊英,韓文霆.基于嶺回歸的土壤含水率高光譜反演研究[J].農業(yè)機械學報,2018,49(5):240-248. ZHANG Zhitao, WANG Haifeng, KARNIELI Arnon, CHEN Junying, HAN Wenting. Inversion of Soil Moisture Content from Hyperspectra Based on Ridge Regression[J]. Transactions of the Chinese Society for Agricultural Machinery,2018,49(5):240-248.

復制
分享
文章指標
  • 點擊次數(shù):
  • 下載次數(shù):
  • HTML閱讀次數(shù):
  • 引用次數(shù):
歷史
  • 收稿日期:2017-10-27
  • 最后修改日期:
  • 錄用日期:
  • 在線發(fā)布日期: 2018-05-10
  • 出版日期:
文章二維碼