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Search results for: FINITE-DIFFERENCE TIME-DOMAIN (FDTD) METHODS
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ECHOES REDUCTION DURING DIGITAL DATA TRANSMISSION IN HYDROACOUSTIC CHANNEL – LABORATORY EXPERIMENT
PublicationThe possibility of using a hydroacoustic channel for digital data transmission is very limited. This is due to the effect of multipath propagation of the emitted acoustic wave and the damping of the mechanical wave in this medium, which increase with frequency. The first of these phenomena results in inter-symbol interference disturbances in data transmission systems, including even hundreds of symbols. Due to the number of reflections...
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Privacy-Preserving, Scalable Blockchain-Based Solution for Monitoring Industrial Infrastructure in the Near Real-Time
PublicationThis paper proposes an improved monitoring and measuring system dedicated to industrial infrastructure. Our model achieves security of data by incorporating cryptographical methods and near real-time access by the use of virtual tree structure over records. The currently available blockchain networks are not very well adapted to tasks related to the continuous monitoring of the parameters of industrial installations. In the database...
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Evaluation of high-frequency roughness measurement errors for composite and ceramic surfaces after machining
PublicationPrecise characterisation of surface topography is of the greatest importance since many factors directly affect the accuracy of the whole measurement process. In this paper, the variety of surface topographies from machined composite and ceramic workpieces was studied with a special emphasis on the measurement results. Surfaces were subjected to the ground diamond, honing and milling processes. Measurement results were analysed...
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Autistic Employees’ Technology-Based Workplace Accommodation Preferences Survey—Preliminary Findings
PublicationBackground: There has been an increase in the number of research studies focused on the design of accommodations aimed at improving the well-being and work performance of autistic employees. These accommodations took various forms; some of them were based on modification of management practices, for example, support in the area of effective communication, or involved modifications to the physical working environment aimed at limiting...
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Multi-sensor monitoring of the corrosion rate and the assessment of the efficiency of a corrosion inhibitor in utility water installations
PublicationThis paper presents an implementation of the monitoring of the corrosion rate and the assessment of the efficiency of a corrosion inhibitor in a utility water installation using an automated corrosion monitoring system. Due to the fact that the corrosion inhibitor was added to water intended for human consumption, it was necessary to build a multi-sensor monitoring system. In order to implement corrosion monitoring using a linear...
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Green aspects of techniques for the determination of pesticides in fruits and vegetables
PublicationApplied all over the world, pesticides are some of the most dangerous pollutants of the environment because of their stability, mobility, their ability to accumulate in the environment and their consequent long-term adverse effects on living organisms in general and human health in particular. Their presence in the environment is a particular danger. It is therefore crucial to monitor pesticide residues using all available analytical...
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Electricity demand prediction by multi-agent system with history-based weighting
PublicationEnergy and load demand forecasting in short-horizons, over an interval ranging from one hour to one week, is crucial for on-line scheduling and security functions of power system. Many load forecasting methods have been developed in recent years which are usually complex solutions with many adjustable parameters. Best-matching models and their relevant parameters have to be determined in a search procedure. We propose a hybrid...
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Computer-assisted assessment of learning outcomes in the laboratory of metrology
PublicationIn the paper, didactic experience with broad and rapid continuous assessment of students’ knowledge, skills and competencies in the Laboratory of Metrology, which is an example of utilisation of assessment for learning, is presented. A learning management system was designed for manage, tracking, reporting of learning program and assessing learning outcomes. It has ability to provide with immediate feedback, which is used by the...
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Road safety information system in Poland - supporting tools and their development
PublicationAs a signatory to the UN Declaration on road safety and member of the EU, Poland has an obligation to comply with relevant EU policies and in particular to halve the overall number of road deaths by 2020. To monitor the progress in reaching the targets, the road safety situation must be evaluated and its processes understood. For this purpose regional and national road safety observatories were launched in Poland, which triggered...
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An Archaeological - Architectural Documentation Based on Close Range Photogrammetry
PublicationWisłoujście Fortress is a historical defensive object located on the southwest coast of the Gulf of Gdańsk. Fort Carre, Eastern Sconce and Ravelin are parts of this postmediaeval fortification. In view of planned regeneration of this fortification complex, at the initiative of the Gdańsk History Museum and Institute of Archaeology and Ethnology of the University of Gdańsk it was decided to perform a documentation of one Fortress...
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UAV IN TODAYS PHOTOGRAMMETRY – APPLICATION AREAS AND CHALLENGES
PublicationThere a few important factors, that nowadays, unmanned aerial vehicles (UAV) are used by wider community, and for cases and applications, that cannot be performed never before. Small UAVs, as a photogrammetry measurement tool provide flexibility, reliability, are safe and easy to use, can be deployed in minutes, initial measurement can be delivered yet on the field, and final accurate measurements are calculated in a very short...
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The dynamic signature verification using population-based vertical partitioning
PublicationThe dynamic signature is an attribute used in behavioral biometrics for verifying the identity of an individual. This attribute, apart from the shape of the signature, also contains information about the dynamics of the signing process described by the signals which tend to change over time. It is possible to process those signals in order to obtain descriptors of the signature characteristic of an individual user. One of the methods...
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Using the ultrasonic tomography method to study the condition of wooden beams from historical buildngs
PublicationThe need to evaluate the integrity of wooden structural elements is constantly increasing. Non-destructive methods are becoming more popular in this field of research. One type of non-destructive testing is the ultrasonic imaging method, which allows the analysis of internal wood structures without disturbing their state and integrity. In this study, we are interested in assessing the effect of wood condition on the ultrasound...
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AGREEprep – Analytical greenness metric for sample preparation
PublicationThis work proposes for the first time, a metric tool that gives prominence to sample preparation. The developed metric (termed AGREEprep) was based on 10 categories of impact that were recalculated to 0 e1 scale sub-scores, and then used to calculate the final assessment score. The criteria of assessment evaluated, among others, the choice and use of solvents, materials and reagents, waste generation, energy consumption, sample...
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Breastfeeding as a regulating factor of the development of the intestinal microbiome in the early stages of life
PublicationSince the first bacterial inhabitants of the human gastrointestinal tract were identified, a lot of research into the study of the human microbiome and its effects on health has been conducted. Currently, it is accepted that humans have a symbiotic relationship with the gut microbiome, though the specifics of this relationship are not well understood. The microbiome of neonates constantly changes and appears to influence many facets...
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Ultrasound-assisted deep eutectic solvent-based liquid–liquid microextraction for simultaneous determination of Ni (II) and Zn (II) in food samples
PublicationA new approach was developed for the simultaneous pre-concentration and determination of Ni (II) and Zn (II) in food samples. This method is based on ultrasound-assisted liquid–liquid micro extraction using hydrophobic deep eutectic solvent (DES) and 1,10-phenanthroline as chelating agent. The effect of several parameters, such as pH, selection and volume of DES, amount of chelating agent, time of sonication and centrifugation,...
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A sense of security and freedom in a residential environment
PublicationThe article is based on the results of a survey carried out among students of architecture faculties in several countries, which examined the students’ knowledge of shaping the housing environment in such a way as to enable them to fulfil two basic and, at the same time, seemingly mutually exclusive psychological needs of a person: a sense of security and a sense of freedom. In examining these issues, particular emphasis was placed...
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Automatic analysis of the aggressive behavior of laboratory animals using thermal video processing
PublicationThe bite detection is very important but difficult element of the social interaction analysis. Standard observation methods like human observer or a camcorder of visible light frequencies fail in this case. However, it is possible to discern cooler spots on the rodent's body that appear after body contact with another individual, and vanish after short time. These spots are assumed to be a saliva trace left on fur after bite. In...
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Bis-phosphonated carbon nanotubes: one pot synthesis and their application as efficient adsorbent of mercury
PublicationEffective, one-pot method of CNTs phosphonylation is presented. Cheap and readily available reagents are used, so the process can be easily transferred to large-scale production. The product was analyzed using spectroscopic methods (FTIR, UV-vis, XPS). Thermal properties of the bis-phosphonated nanotubes are reported for the first time. Newly obtained material was tested as an adsorbent for mercury removal from water. The sorption...
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OPTIMALIZATION OF SORBENT FEEDING IN THE DRY METHOD OF FLUE GAS DESULFURIZATION
PublicationThe swiftly developing sea transport contributes to a considerable increase of fuel usage in the international shipping, which results in the escalation of toxic compounds emitted into the atmosphere. It is followed by the constantly heightened requirements limiting those emissions. In the case of sulfur oxide emission, inside of SECA (Sulfur Emission Control Area), the maximum content of sulfur in the shipping fuels used on the...
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Algorithms for testing security in graphs
PublicationIn this paper we propose new algorithmic methods giving with the high probability the correct answer to the decision problem of security in graphs. For a given graph G and a subset S of a vertex set of G we have to decide whether S is secure, i.e. every subset X of S fulfils the condition: |N[X] \cap S| >= |N[X] \ S|, where N[X] is a closed neighbourhood of X in graph G. We constructed a polynomial time property pseudotester based...
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Comparative analysis of IP-based mobility protocols and fast handover algorithms in IEEE 802.11 based WLANs
PublicationA rapid growth of IP-based networks and services created the vast collection of resources and functionality available to users by means of an uniform method of access - an IP protocol. At the same time, advances in design of mobile electronic devices allowed them to reach utility level comparable to stationary, desktop computers, while still retaining their mobility advantage. Unfortunately, the base IP protocol does not perform...
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Resistant to correlated noise and outliers discrete identification of continuous non-linear non-stationary dynamic objects
PublicationIn this article, specific methods of parameter estimation were used to identify the coefficients of continuous models represented by linear and nonlinear differential equations. The necessary discrete-time approximation of the base model is achieved by appropriately tuned FIR linear integral filters. The resulting discrete descriptions, which retain the original continuous parameterization, can then be identified using the classical...
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Resistant to correlated noise and outliers discrete identification of continuous non-linear non-stationary dynamic objects
PublicationIn this study, dedicated methods of parameter estimation were used to identify the coefficients of continuous models represented by linear and nonlinear differential equations. The necessary discrete-time approximation of the base model is achieved by appropriately tuned FIR linear integral filters. The resulting discrete descriptions, which retain the original continuous parameterization, can then be identified using the classical...
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Chromogenic azomacrocycles with imidazole residue: Structure vs. properties
PublicationNew diazo macrocycles linked by hydrocarbon chain bearing imidazole or 4-methylimidazole residue have been synthetized with satisfactory yield (24–55%). The structure of macrocycles was confirmed by X-ray analysis and spectroscopic methods (1H NMR, MS, FTIR). Metal cation complexation studies were carried out in acetonitrile and acetonitrile-water system. It was found that azomacrocyles form triple-decker complexes with lead(II)....
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Assessment of image processing methods for the determination of propagation of squat-type defects in rails
PublicationWe demonstrate the idea of squat-type defect measurement in the rail and the concept of tracking of the defect development using the techniques of image acquisition and image processing as well as the methods of metric spaces. We introduce the concepts of a set diameter δ(A) and the metric ρ1, which come from the properties of plane figures, to compare and to observe the development of the defects. We characterize the feasibility...
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Experimental and Numerical Investigation of Mechanical Properties of Lightweight Concretes (LWCs) with Various Aggregates
PublicationHigh requirements for the properties of construction materials and activities directed at environment protection are reasons to look for new solutions in concrete technology. This research was directed at solutions affecting the reduction of energy consumption and CO2 emissions. The use of lightweight concretes (LWCs) allows one to meet both conditions at the same time. The purpose of the research presented in this paper was to...
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Linear viscoelastic transversely isotropic model based on the spectral decomposition of elasticity tensors
PublicationThe linear viscoelasticity is still a useful model in the engineering for studying the behavior of materials loaded with different loading rates (frequencies). Certain types of materials reveal also an anisotropic behavior: fiber reinforced composites, asphalt concrete mixtures, or wood, to name a few. In general, researchers try to identify experimentally the dependence of engineering constants like: directional Young’s moduli...
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Alkohol-społeczny problem XXI wieku. Zastosowanie biowskaźników spożywania alkoholu w diagnostyce medycznej.
PublicationAlkohol etylowy jest legalną i ogólnodostępną substancją o działaniu psychoaktywnym. Spożywany w niewielkich ilościach może pozytywnie wpływać na zdrowie, ale jego nadmierna konsumpcja powoduje silne uzależnienie. Może być to przyczyną agresywnych zachowań, przemocy w rodzinie, problemów w kontaktach z ludźmi, problemów z prawem, samobójstw, wypadków samochodowych oraz problemów finansowych. Dlatego też, szybka i jednoznaczna diagnostyka...
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Adaptacyjny system oświetlania dróg oraz inteligentnych miast
PublicationPrzedmiotem rozprawy jest zbadanie praktycznej możliwości wykrywania w czasie rzeczywistym anomalii w systemie oświetlenia drogowego w oparciu o analizę danych ze inteligentnych liczników energii. Zastosowanie inteligentnych liczników energii elektrycznej (Smart Meter) w systemach oświetlenia drogowego stwarza nowe możliwości w zakresie automatycznej diagnostyki takich niepożądanych zjawisk jak awarie lamp, odstępstwa od harmonogramu...
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China’s international trade and global value chains under One-Belt One-Road initiative
PublicationResearch background: After China acceded to the WTO in 2001, its foreign trade has expanded rapidly to be the largest share in the world. However, China's economic development changing from high-speed growth to medium high-speed growth in recent years. At the same time, the increase in labour cost and overcapacity also hinder China’s international trade. In order to solve these challenges and strengthening ties...
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Maximizing Bio-Hydrogen and Energy Yields Obtained in a Self-Fermented Anaerobic Bioreactor by Screening of Different Sewage Sludge Pretreatment Methods
PublicationEgypt faces significant challenges in managing its sewage sludge generated in large quantities from wastewater treatment plants. This study investigates the feasibility of utilizing sewage sludge as a renewable resource for hydrogen production through anaerobic digestion at the 100 L bioreactor level. Hydrogen is considered a promising alternative energy source due to its high energy content and environmental benefits. To optimize...
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The searchlight problem for road networks
PublicationWe consider the problem of searching for a mobile intruder hiding in a road network given as the union of two or more lines, or two or more line segments, in the plane. Some of the intersections of the road network are occupied by stationary guards equipped with a number of searchlights, each of which can emit a single ray of light in any direction along the lines (or line segments) it is on. The goal is to detect the intruder,...
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Analysis of the impact of wastewater discharge on recipients: synergistic approach
PublicationThe dissertation presents the analysis of chemical and microbial composition of wastewater and examines the impact of wastewater discharge on the environment. Various case studies were analysed: from small settlements in a pristine European Arctic, to large municipal wastewater treatment plants in areas subjected to greater anthropogenic pressure. In order to comprehensively analyse the impact of wastewater discharge on the receiving...
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Transcriptomic landscape of blood platelets in healthy donors
PublicationBACKGROUND Blood platelet RNA-sequencing is increasingly used among the scientific community. Aberrant platelet transcriptome is common in cancer or cardiovascular disease, but reference data on platelet RNA content in healthy individuals are scarce and merit complex investigation. METHODS We sought to explore the dynamics of platelet transcriptome. Datasets from 204 healthy donors were used for the analysis of splice variants,...
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Variable-fidelity CFD models and co-Kriging for expedited multi-objective aerodynamic design optimization
PublicationPurpose – Strategies for accelerated multi-objective optimization of aerodynamic surfaces are investigated, including the possibility of exploiting surrogate modeling techniques for computational fluid dynamic (CFD)-driven design speedup of such surfaces. The purpose of this paper is to reduce the overall optimization time. Design/methodology/approach – An algorithmic framework is described that is composed of: a search space reduction,...
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A Development of a Capacitive Voltage Divider for High Voltage Measurement as Part of a Combined Current and Voltage Sensor
PublicationThis article deals with the development of capacitive voltage divider for high voltage measurements and presents a method of analysis and optimization of its parameters. This divider is a part of a combined voltage and current sensor for measurements in high voltage power networks. The sensor allows continuous monitoring of the network distribution status and performs a quick diagnosis and location of possible network failures....
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Wpływ modernizacji linii kolejowych na poprawę wybranych parametrów techniczno - eksploatacyjnych
PublicationW artykule przedstawiono pojęcie jakości robót inwestycyjnych poszczególnych elementów infrastruktury kolejowej oraz metody jej oceny. Skupiono uwagę na jakości początkowej nawierzchni kolejowej po pracach modernizacyjnych na sieci Polskich Linii Kolejowych. Wskazano błędy oraz najczęstsze problemy techniczne występujące w trakcie trwania robót oraz po ich zakończeniu na poszczególnych etapach odbiorów. Opisano wpływ jakości początkowej...
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Functional safety and reliability analysis methodoloogy for hazardous industrial plants
PublicationThis monograph is devoted to current problems and methods of the functional safety and reliability analyses of the programmable control and protection systems for industrial hazardous plants. The results of these analyses are useful in the process of safety management in life cycle, for effective reducing relevant risks at the design stage, and then controlling these risks during the operation of given installation. The methodology...
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On Computationally-Efficient Reference Design Acquisition for Reduced-Cost Constrained Modeling and Re-Design of Compact Microwave Passives
PublicationFull-wave electromagnetic (EM) analysis has been playing a major role in the design of microwave components for the last few decades. In particular, EM tools allow for accurate evaluation of electrical performance of miniaturized structures where strong cross-coupling effects cannot be adequately quantified using equivalent network models. However, EM-based design procedures (parametric optimization, statistical analysis) generate...
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Improved Modeling of Microwave Structures Using Performance-Driven Fully-Connected Regression Surrogate
PublicationFast replacement models (or surrogates) have been widely applied in the recent years to accelerate simulation-driven design procedures in microwave engineering. The fundamental reason is a considerable—and often prohibitive—CPU cost of massive full-wave electromagnetic (EM) analyses related to solving common tasks such as parametric optimization or uncertainty quantification. The most popular class of surrogates are data-driven...
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Design-Oriented Two-Stage Surrogate Modeling of Miniaturized Microstrip Circuits with Dimensionality Reduction
PublicationContemporary microwave design heavily relies on full-wave electromagnetic (EM) simulation tools. This is especially the case for miniaturized devices where EM cross-coupling effects cannot be adequately accounted for using equivalent network models. Unfortunately, EM analysis incurs considerable computational expenses, which becomes a bottleneck whenever multiple evaluations are required. Common simulation-based design tasks include...
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Ontological Modeling for Contextual Data Describing Signals Obtained from Electrodermal Activity for Emotion Recognition and Analysis
PublicationMost of the research in the field of emotion recognition is based on datasets that contain data obtained during affective computing experiments. However, each dataset is described by different metadata, stored in various structures and formats. This research can be counted among those whose aim is to provide a structural and semantic pattern for affective computing datasets, which is an important step to solve the problem of data...
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Using Decisional DNA to Enhance Industrial and Manufacturing Design: Conceptual Approach
PublicationDuring recent years, manufacturing organizations are facing market changes such as the need for short product life cycles, technological advancement, intense pressure from competitors and the continuous customers’ expectation for high quality products at lower costs. In this scenario, knowledge and its associated engineering/management of every stage involved in the industrial design has become increasingly important for manufacturing...
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Efficiency of gas mixtures detection by resistive gas sensors
PublicationResistive gas sensors are very popular and are commonly used to detect various gases and their mixtures. Theeir main disadvantage is very limited selectivity. Practical use of gas sensors in environenmental applications requires determination of concentration of a few mixed gases at the same time. We would like to present recent results of gas detection improvement by utilizing a single gas sensor and additional measurements to...
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The use of a one-step PCR method for the identification of Microsporum canis and Trichophyton mentagrophytes infection of pets
PublicationIntroduction: Dermatophytes are a closely related group of keratinophilic fungi. They encompass important etiological agents of superficial fungal infections. These fungi are able to invade keratinized tissues of humans and animals, causing dermatophytosis (ringworm) of hair, nails or skin. The aim: Traditional diagnostics of ringworm is based on morphological identification of cultured fungi and is time-consuming. Materials and methods:...
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CHROMATOGRAPHIC TECHNIQUES IN PHARMACEUTICAL ANALYSIS IN POLAND: HISTORY AND THE PRESENCE ON THE BASIS OF PAPERS PUBLISHED IN SELECTED POLISH PHARMACEUTICAL JOURNALS IN XX CENTURY
PublicationFor a long time, chromatographic techniques and techniques related to them have stimulated the development of new procedures in the field of pharmaceutical analysis. The newly developed methods, characterized by improved metrological parameters, allow for more accurate testing of, among others, the composition of raw materials, intermediates and final products. The chromatographic techniques also enable studies on waste generated...
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Loudness Scaling Test Based on Categorical Perception
PublicationThe main goal of this research study is focused on creating a method for loudness scaling based on categorical perception. Its main features, such as: way of testing, calibration procedure for securing reliable results, employing natural test stimuli, etc., are described in the paper and assessed against a procedure that uses 1/2-octave bands of noise (LGOB) for the loudness growth estimation. The Mann-Whitney U-test is employed...
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New generation of analytical tests based on the assessment of enzymatic and nuclear receptor activity changes induced by environmental pollutants
PublicationAnalytical methods show great potential in biological tests. The analysis of biological response that results from environmental pollutant exposure allows: (i) prediction of the risk of toxic effects and (ii) provision of the background for the development of markers of the toxicants presence. Bioanalytical tests based on changes in enzymatic activity and nuclear receptor action provide extremely high specificity and sensitivity....
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Molecular mobility of water protons under interaction with chemically modified starches. DSC and HMR-relaxation investigations
PublicationThe change of water protons mobility in the system chemically modified starches – water were investigated by DSC and NMR-relaxation methods. The amount of unfrozen water at subzero temperature as well as additional unfrozen water which appears after gelatinization have lower values for chemically modified starches in comparison with the native starch. The proton spin-spin relaxation time Т2 for chemically modified starch samples,...