Sergey Kucheryavskiy

Aalborg University · Department of Chemistry and Bioscience

Modern hyperspectral images, especially acquired in remote sensing and from on-field measurements, can easily contain from hundreds of thousands to several millions of pixels. This often leads to a quite long computational time when, eg, the images are decomposed by Principal Component Analysis (PCA) or similar algorithms. In this paper, we are goi...

The paper describes mdatools – R package, which implements mainly basic but also some advanced chemometric methods providing a unified interface and user experience. The package was created to give a low entry level for beginners, so they can start using the implemented methods without writing much of code. While progressing, though, users can also...

A generalization of Procrustes Cross-Validation - recently introduced novel approach for validation of chemometric models - is proposed. The generalized approach is faster than its predecessor by several orders of magnitude and can be used for validation of a wider range of models. Furthermore, it provides new tools for exploring the heterogeneity...

The aim of this paper is twofold. First, it serves as a comprehensive tutorial on Data‐Driven Soft Independent Modelling of Class Analogy (SIMCA) (DD‐SIMCA) method for one‐class classification. It covers all practical aspects of developing, validation, and application of DD‐SIMCA models, using a set of simple examples. Second, it introduces web app...

This study demonstrates the sustainable advancement of fermentation media by blending the organic fraction of municipal solid waste (OFMSW) with organosolv beechwood cellulose. Investigations examined the effects of enzyme dosages and OFMSW integration into organosolv beechwood cellulose on sugar yield. The findings indicate that OFMSW inclusion an...

Multivalent biomass-based H 2 S scavengers have been prepared in a few steps from cheap and readily available chemicals and evaluated using state-of-the-art in situ Raman spectroscopy under reaction conditions relevant to industrial applications.

Well-functioning and stable microbial communities are critical for the operation of activated sludge (AS) wastewater treatment plants (WWTPs). Bioaugmentation represents a potentially useful approach to recover deteriorated systems or to support specific AS processes, but its application in full-scale WWTPs is generally problematic. We conducted a...

European plaice (Pleuronectes platessa) is a key species in commercial fisheries in the North Sea, Skagerrak, Kattegat, and Baltic Sea. The reformed European Union Common Fisheries Policy includes the possibility of exemptions from the landing obligation for “species for which scientific evidence demonstrates high survival rates”. Discard survival...

Large amount of information in hyperspectral images (HSI) generally makes their analysis (e.g., principal component analysis, PCA) time consuming and often requires a lot of random access memory (RAM) and high computing power. This is particularly problematic for analysis of large images, containing millions of pixels, which can be created by augme...

Significance Wastewater treatment plants are engineering technologies used worldwide to protect the environment and human health. Microbial communities sustain these plants, so it is crucial to know the key factors responsible for the community assembly. We show, in contrast to existing understanding, that microbial immigration largely controls the...

Basic tools for exploration and interpretation of Principal Component Analysis (PCA) results are well-known and thoroughly described in many comprehensive tutorials. However, in the recent decade, several new tools have been developed. Some of them were originally created for solving authentication and classification tasks. In this paper we demonst...

Anaerobic digestion (AD) is a key technology at many wastewater treatment plants (WWTPs) for converting surplus activated sludge to methane-rich biogas. However, the limited number of surveys and the lack of comprehensive datasets have hindered a deeper understanding of the characteristics and associations between key variables and the microbial co...

Eddy current (EC) measurements, widely used for diagnostics of conductive materials, are highly dependent on physical properties and geometry of a sample as well as on a design of an EC-sensor. For a sensor of a given design, the conductivity and thickness of a sample as well as the gap between the sample and the sensor (lift-off) are the most infl...

div> Basic tools for exploration and interpretation of Principal Component Analysis (PCA) results are well- known and thoroughly described in many comprehensive tutorials. However, in the recent decade, several new tools have been developed. Some of them were originally created for solving authentication and classification tasks. In this paper we...

Conventional wet chemical methods for the determination of soil phosphorus (P) pools, relevant for environmental and agronomic purposes, are labor-intensive. Therefore, alternative techniques are needed, and a combination of the spectroscopic techniques-in this case, laser-induced breakdown spectroscopy (LIBS)-and visible near-infrared spectroscopy...

In this paper we propose a new approach for validation of chemometric models. It is based on k-fold cross-validation algorithm, but, in contrast to conventional cross-validation, our approach makes possible to create a new dataset, which carries sampling uncertainty estimated by the cross-validation procedure. This dataset, called pseudovalidation...

Filamentous bulking is a common serious operational problem leading to deteriorated sludge settling that has long been observed in activated sludge biological wastewater treatment systems. A number of bacterial genera found therein possess filamentous morphology, where some have been shown to be implicated in bulking episodes (e.g., Ca. Microthrix)...

Anaerobic digestion (AD) is a key technology at many wastewater treatment plants (WWTPs) for converting surplus activated sludge to methane-rich biogas. However, the limited number of surveys and the lack of comprehensive data sets have hindered a deeper understanding of the characteristics and associations between key variables and the microbiome...

An open source MATLAB tool implementing the standard Partial least squares discriminant analysis (PLS-DA) method as well as its recent developments, known as multiclass PLS-DA in hard and soft versions, is presented. The main functionality of the tool and usage scenarios are described using a real-world example. A brief introduction to the underlyi...

div> In this paper we propose a new approach for validation of chemometric models. It is based on k-fold cross-validation algorithm, but, in contrast to conventional cross-validation, our approach makes possible to create a new dataset, which carries sampling uncertainty estimated by the cross-validation procedure. This dataset, called pseudo-vali...

Triazine is one of the most commonly used scavengers for removal of hydrogen sulphide in the offshore oil and gas industry, but the kinetics of the scavenging reactions are still poorly understood. In this work the feasibility of Raman spectroscopy for on-line monitoring of the aqueous phase reaction between 1,3,5-tri-(2-hydroxyethyl)-hexahydro-s-t...

The project aim was to estimate N uptake (Nup), dry matter yield (DMY) and crude protein concentration (CP) of forage crops both during typical harvest times and at a very early developmental stage. Canopy spectral reflectance of legume and grass mixtures was measured in Sweden using a commercialized radiometer (400–1000 nm range). In total, 377 pl...

Decision trees and their ensembles became quite popular for data analysis during the past decade. One of the main reasons for that is current boom in big data, where traditional statistical methods (such as, e.g., multiple linear regression) are not very efficient. However, in chemometrics these methods are still not very widespread, first of all b...

The feasibility of image texture analysis to evaluate X-ray images of fungal-infected maize kernels was investigated. X-ray images of maize kernels infected with Fusarium verticillioides and control kernels were acquired using high-resolution X-ray micro-computed tomography. After image acquisition and pre-processing, several algorithms were develo...

This research aims to study the wettability and zeta potential of photoactive TiO2/GO composite membranes. Full factorial design was utilized for the investigation of the influence of TiO2 content, reduction temperature and UV activation on the surface energy and zeta-potential of TiO2/GO composite membranes. Multivariate data analysis of FTIR data...

The influence of co-solvents on hydrothermal liquefaction (HTL) of Fallopia Japonica was studied as a function of temperature. Combination of low and high-resolution mass spectrometry with multi-layered data mining strategy resulted in a comprehensive characterization of the reaction products, mostly water-soluble organics (WSO) with a broad spectr...

The aim of the study was to assess the levels of PCBs in the breast milk of some Ghanaian women at suspected hotspot and relatively non-hotspot areas and to find out if the levels of these PCBs pose any risk to the breastfed infants. A total of 128 individual human breast milk were sampled from both primiparae and multiparae mothers. The levels of...

Multi-element fingerprinting demonstrates some potential for tracing the origin of agricultural products but not for discriminating among crop cultivars and nutrient management (source, rate). With principal component analysis (PCA) and univariate statistics, we examined 19 elements in grains from two winter wheat cultivars (Hereford, Mariboss) gro...

Adjustment of the ionic composition and strength of injected or imbibed brine for enhanced oil recovery (EOR) in carbonate reservoirs has been an area of active research for the past two decades. Despite many successful laboratory and field applications, the method has been re- ported ineffective in other cases. Most of the published results attrib...

Cardiovascular disease is the leading cause of death worldwide and patients with severe symptoms undergo cardiac surgery. Even after uncomplicated surgeries, some patients experience postoperative complications such as lung injury. We hypothesized that the procedure elicits metabolic activity that can be related to the disease progression, which...

The effect of eddy currents is widely used for diagnostics of conductive materials. It allows to create very simple and inexpensive systems for non-destructive measurements. However, the results of the measurements depend on many factors, including first of all, a conductivity of material and a margin between a sample and a measurement sensor. If b...

NIR hyperspectral imaging was evaluated to classify maize kernels of three hardness categories: hard, medium and soft. Two approaches, pixel-wise and object-wise, were investigated to group kernels according to hardness. The pixel-wise classification assigned a class to every pixel from individual kernels and did not give acceptable results because...

Hydrothermal liquefaction (HTL) is one of the most promising biomass reforming processes for production of drop-in biofuels. The technique has been under development for a number of years, and yet, due to its complexity, it has always been difficult to generalize information about the optimal conditions. The main issue regards to the limited knowle...

Introduction Pulmonary dysfunctions resulting in postoperative hypoxaemia is a common complication of cardiac surgery. The disease is challenging as it lacks predictive biomarkers. Since a comprehensive metabolic overview of lung microvasculature injury is lacking, we have compared the metabolome of patients undergoing cardiac surgery from blood co...

The concepts of pure variables as well as spectral unmixing methods that utilize the concept are presented. The methods have a number of advantages, comparing to alternatives, including speed (one of the fastest curve resolution methods), sequential procedure for resolving of pure components (which means there is no need for preliminary determinati...

This paper presents a study of the energy balance of utilising nature conservation biomass from meadow habitats in Danish biogas production. Utilisation of nature conservation grass in biogas production in Denmark represents an interesting perspective for enhancing nature conservation of the open grassland habitats, while introducing an alternative...

A feasibility study on using Raman spectral imaging for visualization and analysis of filler distribution in chalk filled polypropylene samples has been carried out. The spectral images were acquired using a Raman spectrometer with 785 nm light source. Eight injection-molded samples with concentration of chalk 25% and 50% were used in the experimen...

Estimation of nucleation and crystal growth rates from microscopic information is of critical importance. This can be an especially challenging task if needle growth of crystals is observed. To address this challenge, an image analytical method for counting of needle-shaped crystals and estimating their length is presented. Since the current algori...

The possibility of using near-infrared (NIR) spectroscopy for monitoring of liquid whey quality parameters during protein production process has been tested. The parameters included total solids, lactose, protein and fat content. The samples for the experiment were taken from real industrial processes and had a large variability for most of the par...

Regression models for predicting preharvest dry matter (DM) and soluble solids content (SSC), based on two spectral ranges (680-1000 nm and 1100-2350 nm), were compared. Models based on longer NIR spectra were more successful for both parameters (DM/SSC: R-2 = 0.78-0.84; RMECV = 0.78/0.44; LVs = 6/7). SSC prediction was better than expected conside...

Fruit dry matter (DM) and soluble solids content (SSC) are primarily composed of carbohydrate and are standard parameters for assessing quality. Near infrared spectroscopy provides potential for non-destructive fruit quality analysis but the collinearity between DM and SSC is an issue for prediction. Shorter wavelength spectra have been used for th...

A new method for victims' age estimation, based on the image processing and analysis of remains bones structure, is proposed. Digital images of lumbar vertebras cuts were used as a major information source. The age related properties were extracted from the images using classic texture analysis approach based on statistical analysis of grey-level c...

Methods for processing and analysis of medical images are observed. A method for recognition and classification of blood cells, based on the black-box model, is proposed. Two approaches (wavelet transformation and angle measure technique) are used for construction of feature vectors and PLS discriminant analysis is used for discrimination and class...

A new approach for discrimination of objects on hyperspectral images, which combines state-of-art image processing methods and multivariate image analysis, is proposed. The basic idea of the approach is to build a joint principal component space for all objects' pixels, detect patterns, pixels from a particular object shared in this space, and use...

The paper's focus is the use of spectral images for the distinction of small archaeological anomalies on the basis of the authors work. Special attention is given to the ground truthing perspective in the discussion of a number of cases from Norway. Different approaches to pattern-recognition are considered in the light of the increasing availabili...

The paper presents an overview of methods for extracting useful information from digital images. It covers various approaches that utilized different properties of images, like intensity distribution, spatial frequency content and several others. A few case studies including isotropic and heterogeneous, congruent and non-congruent images are used t...

A new method for calculation of latent variable space for exploratory analysis and dimension reduction of large hyperspectral images is proposed. The method is based on significant downsampling of image pixels with preservation of pixels' structure in feature (variable) space. To achieve this, information about pixels density in principal component...

Image analysis is an efficient technique used in many areas of science and industry. However, in process analytical applications it tends to be an ancillary tool, used mainly for visual monitoring or measuring some geometrical properties. At the same time, there are many other important aspects of the process samples appearance, besides measurable...

Analysis and classification of non-isotropic images with Angle Measure Technique (AMT) is augmented with a new object contour unfolding. The new unfolding algorithm is presented and compared with earlier unfolding options in AMT. The new unfolding with Projection on Latent Structures (PLS) discriminant analysis was applied for classification of dig...

The effects of digitization and quantification in one- and two-dimensional signals on angle measure technique (AMT) texture analysis are described in order to find optimal corrections. AMT analysis with varying parameters has been carried out on simulated and real images as well on time-series data. All images and signals are of high resolution in...

Texture characterization plays an important role in image analysis as do signal complexity characterization for one-dimensional arrays (time series a.o.). One of the most effective approaches for this task is Angle Measure Technique (AMT) which simultaneously describes the complexity of images or signals at all scales. This approach is not widespre...

The fourth regular event in the Drushbametrics (friendship-metrics) program, WSC-4, took place in Chernogolovka, a science city near Moscow, Russia, February 15 – 18, 2005. The conference was organized by the Russian Chemometrics Society, the Institute of Problems of Chemical Physics and the Institute of Chemical Physics. Beginning with this confer...

ACABS, AUE (visiting researcher) 2) ACABS, Ålborg University Esbjerg (AUE), Denmark Extended abstract Investigation of deformation structures and fracture for porous metals and materials under plastic deformation allows us to understand these processes in detail and to delineate the most effec-tive operative conditions. Fracture surfaces display st...

The structure of porous copper and iron materials with a porosity ranging from 5 to 45% was studied by fractal analysis. A relationship between the fractal dimension of the porous space boundary and the porosity value is established. A correlation between topological features of the porous material structure and the fractal dimension of the interfa...