# Joseph DubrovkinWestern Galilee College · Multidisciplinary Department

Joseph Dubrovkin

PhD

Mathematical processing of matrix data.

## About

130

Publications

133,272

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140

Citations

Introduction

Additional affiliations

Education

January 1982 - January 1988

## Publications

Publications (130)

In the earlier days of spectrometry, identifying and quantizing unknown atoms, functional molecular fragments, and different compounds in samples under study involved non-automated instruments, and were performed using parameters of the most informative isolated spectral lines and bands, namely, locations of their peaks and intensities. With the de...

This book summarizes studies and major materials on data compression methods in analytical spectroscopy, including some important topics on imaging. Its rigorous mathematical basis, in-depth detailed description, and numerous examples of the applications in chemistry and physics will be of value for theorists, practitioners, and students specializi...

Storage, processing, and transfer of huge matrices are becoming challenging tasks in the process analytical technology and scientific research. Matrix compression can solve these problems successfully. We developed a novel compression method of spectral data matrix based on its low-rank approximation and the fast Fourier transform of the singular v...

Supplementary bibliography to the book
Continued
Joseph Dubrovkin. Derivative Spectroscopy. Cambridge Scholar Publishing. 2021

For hundreds of years, improving the resolution of scientific instruments was one of the main concerns of optical techniques. The importance of this problem is shown by studies which claim that the human perception of images strongly depends on their resolution. Particularly in spectroscopy, overlapping contours make it difficult to assign each ele...

Supplementary programs to the book "Derivative Spectroscopy"

Bibliography Derivative Spectroscopy

This book will appeal to both practitioners and researchers in both industrial and university chemical, bio-pharmaceutical, and physical, analytical laboratories, and students specializing in analytical spectroscopy, bio-pharmaceutical analysis, chemometrics, and laser physics. It sums up the results of more than half a century of research in deriv...

Supplementary bibliography to the book
Joseph Dubrovkin. Derivative Spectroscopy. Cambridge Scholar Publishing. 2021
https://www.cambridgescholars.com/product/978-1-5275-6348-3

This brief review serves pedagogical purposes and can be used as a free source of information in relevant training courses.

This preprint is the authorized translation from Russian. We modified the source by taking into account some new publications. In our opinion, the paper may serve as a textbook for educational purposes.

This preprint is the authorized translation from Russian. The source taken from our book
[ Dubrovkin, J. & Belikov, V. G. (1988). Derivative Spectrometry. Theory, Technics, Application. Rostov University. [Russian]] was modified. In our opinion, the reading may be interesting from a historical point of view. It can also be used for education purpo...

Excited-state reactions (ESR) play an essential role in chemical, physical, and biological processes. The mathematical models are usually used to study ESR in kinetics and steady-state regimes. In these models, the excitation pulse populates the first excited state (the first singlet level) of the primary molecular form. Recently, researchers' paid...

In this preprint, we intend to demonstrate a simple method of smoothing noisy spectra using the Fast Fourier Transform. Smoothing of noisy data using Fourier Transform (FT) has a long history: from empirical algorithms of Lanczos to the mathematically rigorous regularization methods of Tikhonov which are continuously developed. In spectroscopy, the...

Old materials published in 1980th years in Russian and unknown to English readers became the basis of this preprint.
The first articles dedicated to the spectra processing in the Fourier domain are:
1. K. R. Betty, G. Horlick. A Simple and Versatile Fourier Domain Digital Filter. Appl. Spectr.30, 23, 1976.
2. J. Dubrovkin, S. Zubarev. Fourier tran...

The author of the present communication devoted many years of his youth to study "Derivative Spectroscopy" and, particularly, SGF. Unfortunately, many old articles were written in Russian and, therefore, escaped the attention of the English-speaking reader. Now, the author decided to publish free sources of English versions of some of his works. Ou...

Part 3. Computer-based tutorial on chemometrics. Multivariate Calibration and Prediction

The tutorial is intended for a wide range of readers including practitioners and researchers of industrial and university analytical laboratories as well for students specializing in analytical spectroscopy and chemometrics.

Excited-state reactions (ESR) are of overwhelming importance in chemistry, physics and biology. Kinetics and steady-state characteristics of ESR are usually analyzed in the framework of the model, in which the first excited state of the initial form is populated. Due to the growing attention which is lately paid to the reactions excited through the...

It was shown that linear transformations are suitable for use in multivariate calibration in NIR spectroscopy as data compression tools. PLS calibration models were built using spectral data transformed by expansion in the series of classical orthogonal polynomials, Fourier and wavelet harmonics. These models allowed estimating properties of diesel...

Effect of intensity redistribution of two fluorescence bands of N,N'-Dimethylaminobenzonitrile in polar solutions of the different viscosity was studied using selective UV irradiation over the red edge of the main absorption band. The effect being depends on temperature and viscosity, indicated eloquently strong inhomogeneous spectral broadening ap...

A method for deconvoluting strongly overlapping spectral bands into separate components that enables the uniqueness of the deconvolution procedure to be monitored was proposed. An asymmetric polynomial-modified function subjected to Fourier filtering (PMGFS) that allowed more accurate and physically reasonable band shapes to be obtained and also im...

The dependences of the relative peak shifts of the second-order derivatives of spectral doublets and of the deconvoluted doublets on the separation of the doublet components were evaluated numerically. Doublets were composed of symmetrical Gaussian and Lorentzian lines with widely ranging relative intensities and widths. It was shown that the decon...

The Big Data approach to the Process Analytical Technology was proposed and discussed. The main stages of Analytical Big Data processing have been described. The Partial Least Squares regression and Principal Component Analysis of huge data matrices were performed using Fourier compression.

It is shown that the errors of quantitative analysis of multicomponent mixtures using absorption spectra perturbed by randomly varying baseline, could be significantly reduced by the introduction of
the noise covariance matrix in the least-squares estimation. The effectiveness of the proposed method is demonstrated on the example of Excedrin drug a...

The resolution limit of doublets that consist of symmetrical and asymmetrical lines of unequal intensities and widths was, for the first time, evaluated theoretically and numerically using the Sparrow and the information criteria. Gaussian, Lorentzian, Voigt, and sinc–squared-like line shapes were studied. The obtained results may be useful for pra...

For the first time, it was shown theoretically that the condition number of the matrix representing individual bands of the multiplex structure of a spectrum profile is a power function of the band separation. This function strongly depends on the number of the structure components. The results obtained are confirmed by computer modelling. Possible...

## Questions

Questions (105)

I am searching for journals that publish reviews of books on spectroscopy, including analytical chemistry, computers in spectroscopy, and signal processing in spectroscopy.

The multiplex advantage of HTS in signal-to-noise ratio is explained by the fact that light energy incident on the detector significantly increases due to signal collecting from the full set of the masks. If the answer to the question is "Yes", then maybe the signal averaging during a longer time interval may improve S/N without masking?

The example (taken from different sources) is in the attached file.

One can see that the string 'aa' from the lookahead buffer is not in the dictionary, but in the long input string.

Can a string (matched to buffer) leave the dictionary?

Thank you for your interest in this question!

Is it possible, the zero of a Wirtinger derivative of an expression that includes a non-analytical function |z|

^{2 }( z is a complex variable) to be considered a condition for the extremum of a function?Do you know open large datasets of NIR spectra ?

I am looking for very large matrices of NIR spectra (more than 3000-5000 samples) for multivariate calibration. Maybe some data have been published and the matrices are in supplementary materials?

Does it make sense to develop compression methods for large matrices used in chemometrics for multivariate calibration?

The main argument of opponents of this method is “increasing computational power and speed of computers for data processing and unlimited cloud data storage available” do not require compression since the compression slightly reduces the accuracy in multivariate calibration. (Cited from Personal communication).

For example, a robot for venous blood analysis and the Automatic Measurement Systems for venous blood analysis.