Evaluating the characteristics of soil vis-NIR spectra after the removal of moisture effect using external parameter orthogonalization

Geoderma ◽  
2020 ◽  
Vol 376 ◽  
pp. 114568
Author(s):  
Ya Liu ◽  
Chao Deng ◽  
Yuanyuan Lu ◽  
Qianyan Shen ◽  
Haifeng Zhao ◽  
...  
Keyword(s):  
External Parameter ◽  
Moisture Effect

Reducing moisture effects on soil organic carbon content prediction in visible and near-infrared spectra with an external parameter othogonalization algorithm

2020 ◽  
Vol 100 (3) ◽  
pp. 253-262
Author(s):  
Yue Cao ◽  
Nisha Bao ◽  
Shanjun Liu ◽  
Wei Zhao ◽  
Shimeng Li
Keyword(s):  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Infrared Spectra ◽  
Prediction Accuracy ◽  
Near Infrared ◽  
Soil Samples ◽  
External Parameter ◽  
Moisture Effect ◽  
Field Spectroscopy ◽  
Near Infrared Spectra

Field spectroscopy and other efficient hyperspectral techniques have been widely used to measure soil properties, including soil organic carbon (SOC) content. However, reflectance measurements based on field spectroscopy are quite sensitive to uncontrolled variations in surface soil conditions, such as moisture content; hence, such variations lead to drastically reduced prediction accuracy. The goals of this work are to (i) explore the moisture effect on soil spectra with different SOC levels, (ii) evaluate the selection of optimal parameter for external parameter othogonalization (EPO) in reducing moisture effect, and (iii) improve SOC prediction accuracy for semi-arid soils with various moisture levels by combing the EPO with machine learning method. Soil samples were collected from grassland regions of Inner Mongolia in North China. Rewetting laboratory experiments were conducted to make samples moisturized at five levels. Visible and near-infrared spectra (350–2500 nm) of soil samples rewetted were observed using a hand-held SVC HR-1024 spectroradiometer. Our results show that moisture influences the correlation between SOC content and soil reflectance spectra and that moisture has a greater impact on the spectra of samples with low SOC. An EPO algorithm can quantitatively extract information of the affected spectra from the spectra of moist soil samples by an optimal singular value. A SOC model that effectively couples EPO with random forest (RF) outperforms partial least-square regression (PLSR)-based models. The EPO–RF model generates better results with R2 of 0.86 and root-mean squared error (RMSE) of 3.82 g kg−1, whereas a PLSR model gives R2 of 0.79 and RMSE of 4.68 g kg−1.

scholarly journals Removing the moisture effect in soil organic matter determination using NIR spectroscopy and PLSR with external parameter orthogonalization

2019 ◽  
Vol 145 ◽  
pp. 1094-1101 ◽  
Author(s):  
Felipe B. de Santana ◽  
Larissa O. de Giuseppe ◽  
André M. de Souza ◽  
Ronei J. Poppi
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Nir Spectroscopy ◽  
External Parameter ◽  
Moisture Effect

Humidity Distribution Simulation of Passenger Vehicle Cabin

2013 ◽  
Vol 291-294 ◽  
pp. 1880-1883
Author(s):  
Li Ping Xiang
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Air Conditioning ◽  
Passenger Vehicle ◽  
Air Conditioning System ◽  
Moisture Effect ◽  
Vehicle Cabin ◽  
Hygienic Standard ◽  
Computational Fluid Dynamics Cfd ◽  
Passenger Cabin

A numerical model to improve the air-conditioning system of vehicle cabin taking into the cabin air moisture and its transport by the airflow within the enclosure cabin is described. An efficient computational fluid dynamics(CFD) technique is using the “realisable” model. The temperature and humidity fields in the passenger cabin are investigated individually under having or no body moisture. The temperature in the vehicle cabin taking into account human moisture is lower than no taking into account moisture 0.5 °C. The human dispersing moisture effect significantly on the humidity, which lead to the humidity is elevating and the humidity in vehicle cabin is corresponded hygienic standard.

Predicting clay content on field-moist intact tropical soils using a dried, ground VisNIR library with external parameter orthogonalization

Geoderma ◽  
2015 ◽  
Vol 259-260 ◽  
pp. 196-204 ◽  
Author(s):  
Jason P. Ackerson ◽  
José A.M. Demattê ◽  
Cristine L.S. Morgan
Keyword(s):  
Clay Content ◽  
Tropical Soils ◽  
External Parameter
Sign in / Sign up

Export Citation Format

Share Document