EFFECTS OF SOIL MOISTURE CONTENT ON ABSORBANCE SPECTRA OF SANDY SOILS IN SENSING PHOSPHORUS CONCENTRATIONS USING UV-VIS-NIR SPECTROSCOPY

ABSTRACT. This study was conducted to investigate the effects of soil moisture content on the absorbance spectra of sandy soils with different phosphorus (P) concentrations using ultraviolet (UV), visible (VIS), and near-infrared (NIR) absorbance spectroscopy. Sieve sizes were 125, 250, and 600 �m for fine, medium, and coarse, respectively. The medium size of th

IMPROVING PHOSPHORUS SENSING BY ELIMINATING SOIL PARTICLE SIZE EFFECT IN SPECTRAL MEASUREMENT

ABSTRACT. This study investigated the effects of soil particle size on the reflectance spectra of sandy soils using ultraviolet, visible, and near-infrared spectroscopy in sensing phosphorus (P) concentration. Pure sandy soil was graded into three particle sizes. Sieve sizes were 125, 250, and 600 �m for fine, medium, and coarse, respectively. Phosphorus application rates for the soil samples were 0.0, 12.5, 62.5, 175.0, 375.0, 750.0, and 1000.0 mg kg −1. Concentrations of P in the soil samples were analyzed. The reflectance of the samples was measured between 225 and 2525 nm at 1 nm intervals. Overall, soils with coarse particles absorbed light more than those with medium and fine particles. Detection analysis for soil particle sizes was conducted using ratio and discriminant analysis methods. Prediction analyses for P concentration were performed using multiple linear regression (MLR; stepwise and maximum R 2 methods) and linear partial least squares (PLS). Results showed that detection of the particle size in a spectrum and then the prediction of P using individual calibration models for each soil particle size produced lower prediction errors. For the maximum R 2 MLR, stepwise MLR, and linear PLS analyses, respectively, the standard errors of prediction (SEPs) for determining P concentration without removing the particle size effect were 105.8, 106.2, and 69.8 mg kg −1 and after removing the particle size effect were 52.8, 73.4, and 64.4 mg kg −1. Phosphorus (P) is currently measured by methods including chemical analysis, atomic spectroscopy, and chromatography that require sampling, handling

Surface characterization by accurate measurement and image processing systems on machined surfaces of precision cutting tools

High precise measurement techniques and surface structure analysis are required in advanced fields of interchangeable manufacturing and precision engineering. This study presents the characterization of the surface roughness of the machined milling cutters by experimental precision measurements and the image processing tool. The data obtained are compared to assess the surface characterization parameters and computational data in terms of precision, accuracy, sensitivity, repeatability and resolution. In the experimental measurement phase, the roughness measurements and surface topography characterization were performed in the nanotechnology laboratory using the stylus profilometry and digital microscopy. The computational phase was performed using an image processing toolbox with precise evaluation of the roughness for the machined metal surfaces of the end mill cutting tool. The surface parameter database is established exhibiting an advantage over the traditional method. This study reveals a comparison methodology of the end mill surface parameters using both stylus readings and image processing software for widely used end mill cutting tools that have considerable effect on characterization of sensitive manufacturing surface of millings

Measurement and Image Processing Evaluation of Surface Modifications of Dental Implants G4 Pure Titanium Created by Different Techniques

Foreign substances and organic tissue interaction placed into the jaw in order to eliminate tooth loss involves a highly complex process. Many biological reactions take place as well as the biomechanical forces that influence this formation. Osseointegration denotes to the direct structural and functional association between the living bone and the load-bearing artificial implant's surface. Taking into consideration of the requirements in the manufacturing processes of the implants, surface characterizations with high precise measurement techniques are investigated and thus long-term success of dental implant is emphasized on the importance of these processes in this study. In this research, the detailed surface characterization was performed to identify the dependence of the manufacturing techniques on the surface properties by using the image processing methods and using the scanning electron microscope (SEM) for morphological properties in 3D and Taylor Hobson stylus profilometer for roughness properties in 2D. Three implant surfaces fabricated by different manufacturing techniques were inspected, and a machined surface was included into the study as a reference specimen. The results indicated that different surface treatments were strongly influenced surface morphology. Thus 2D and 3D precise inspection techniques were highlighted on the importance for surface characterization. Different image analyses techniques such as Dark-light technique were used to verify the surface measurement results. The computational phase was performed using image processing toolbox in Matlab with precise evaluation of the roughness for the implant surfaces. The relationship between the number of black and white pixels and surface roughness is presented. FFT image processing and analyses results explicitly imply that the technique is useful in the determination of surface roughness. The results showed that the number of black pixels in the image increases with increase in surface roughness