Wood density is a key indicator for tree functionality and end utilization. Appropriate chemometric methods play an important role in the successful prediction of wood by visible near infrared (Vis-NIR) spectroscopy. The objective this study was to select appropriate pre-processing, variable selection multivariate calibration techniques improve accuracy Chinese white poplar (Populus tomentosa c...

objective(s): in spect, the sinogram contains scatter and lack of attenuated counts that degrade the reconstructed image quality and quantity. many techniques for attenuation and scatter correction have been proposed. an acceptable method of correction is to incorporate effects into an iterative statistical reconstruction. here, we propose new maximum likelihood expectation maximization (mlem) ...

introduction: scattered photon is one of the main defects that degrade the quality and quantitative accuracy of nuclear medicine images. accurate estimation of scatter in projection data of spect is computationally extremely demanding for activity distribution in uniform and non-uniform dense media. methods: the objective of this paper is to develop and validate a scatter correction technique t...

Near infrared (NIR) spectroscopy has become a promising technique for the in vivo monitoring of glucose. Several capillary-rich locations in the body, such as the tongue, forearm, and finger, have been used to collect the in vivo spectra of blood glucose. For such an in vivo determination of blood glucose, collected NIR spectra often show some dependence on the measurement conditions and human ...

We propose four methods for finding local subspaces in large spectral libraries. The proposed four methods include (a) cosine angle spectral matching; (b) hit quality index spectral matching; (c) self-organizing maps and (d) archetypal analysis methods. Then evaluate prediction accuracies for global and subspaces calibration models. These methods were tested on a mid-infrared spectral library c...

During the past decades, large amounts of diffuse cadmium (Cd) and zinc (Zn) contaminated soil material have been deposited in the floodplains of the river Rhine in the Netherlands. As spatial information on soil quality is required at different scale levels covering the whole area, characterisation exclusively based on soil sampling and analysis is time-consuming and very expensive. A quicker ...

Reflectance spectra of winter wheat leaves specimens was acquired with portable spectroradiometer and integral sphere, after pretreatment with the method of multiplicative scatter correction(MSC), the principal components calculated were used as the inputs of artificial neural networks to build the Back--Propagation artificial neural networks model(BP-ANN), which can be used to predict moisture...

Introduction: Scatter radiation is one of the major sources of error in nuclear medicine data processing. Different methods of scatter correction have been introduced in order to improve the quality of data. However the best method is to avoid recording of scatter photons in acquisition. The only difference between scattered and non-scattered photons is the energy. Pulse height analyzer i...

introduction: the key characteristics of positron emission tomography (pet) are its quantitative capability and its sensitivity, which allow the in vivo imaging of biochemical interactions with small amounts of tracer concentrations. therefore, accurate quantification is important. however, it can be sensitive to several physical factors. the aim of this investigation is the assessment of the e...