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  • Data Acquisition and Processing for GeoAI Models to Support Sustainable Agricultural Practices
    • Agustin Garcia Pereira
    • Adegboyega Ojo
    • Curry Edward
    • Lukasz Porwol
    2020 Pełny tekst

    There are growing opportunities to leverage new technologies and data sources to address global problems related to sustainability, climate change, and biodiversity loss. The emerging discipline of GeoAI resulting from the convergence of AI and Geospatial science (Geo-AI) is enabling the possibility to harness the increasingly available open Earth Observation data collected from different constellations of satellites and sensors with high spatial, spectral and temporal resolutions. However, transforming these raw data into high-quality datasets that could be used for training AI and specifically deep learning models are technically challenging. This paper describes the process and results of synthesizing labelled-datasets that could be used for training AI (specifically Convolutional Neural Networks) models for determining agricultural land use pattern to support decisions for sustainable farming. In our opinion, this work is a significant step forward in addressing the paucity of usable datasets for developing scalable GeoAI models for sustainable agriculture.

  • Data governance: Organizing data for trustworthy Artificial Intelligence
    • Marijn Janssen
    • Paul Brous
    • Elsa Estevez
    • Luis S. Barbosa
    • Tomasz Janowski
    2020 Pełny tekst GOVERNMENT INFORMATION QUARTERLY

    The rise of Big, Open and Linked Data (BOLD) enables Big Data Algorithmic Systems (BDAS) which are often based on machine learning, neural networks and other forms of Artificial Intelligence (AI). As such systems are increasingly requested to make decisions that are consequential to individuals, communities and society at large, their failures cannot be tolerated, and they are subject to stringent regulatory and ethical requirements. However, they all rely on data which is not only big, open and linked but varied, dynamic and streamed at high speeds in real-time. Managing such data is challenging. To overcome such challenges and utilize opportunities for BDAS, organizations are increasingly developing advanced data governance capabilities. This paper reviews challenges and approaches to data governance for such systems, and proposes a framework for data governance for trustworthy BDAS. The framework promotes the stewardship of data, processes and algorithms, the controlled opening of data and algorithms to enable external scrutiny, trusted information sharing within and between organizations, risk-based governance, system-level controls, and data control through shared ownership and self-sovereign identities. The framework is based on 13 design principles and is proposed incrementally, for a single organization and multiple networked organizations.

  • Data regarding a new, vector-enzymatic DNA fragment amplification-expression technology for the construction of artificial, concatemeric DNA, RNA and proteins, as well as biological effects of selected polypeptides obtained using this method
    • Piotr Skowron
    • Natalia Krawczun
    • Joanna Żebrowska
    • Daria Krefft
    • Olga Żołnierkiewicz
    • Marta Bielawa
    • Joanna Jeżewska-Frąckowiak
    • Łukasz Janus
    • Małgorzata Witkowska
    • Małgorzata Palczewska
    • Adriana Schumacher
    • Anna Wardowska
    • Milena Deptuła
    • Artur Czupryn
    • Piotr Mucha
    • Arkadiusz Piotrowski
    • Paweł Sachadyn
    • Sylwia Rodziewicz-Motowidło
    • Michal Pikuła
    • Agnieszka Zylicz-Stachula
    2020 Pełny tekst Data in Brief

    Applications of bioactive peptides and polypeptides are emerging in areas such as drug development and drug delivery systems. These compounds are bioactive, biocompatible and represent a wide range of chemical properties, enabling further adjustments of obtained biomaterials. However, delivering large quantities of peptide derivatives is still challenging. Several methods have been developed for the production of concatemers – multiple copies of the desired protein segments. We have presented an efficient method for the production of peptides of desired length, expressed from concatemeric Open Reading Frame. The method employs specific amplification-expression DNA vectors. The main methodological approaches are described by Skowron et al., 2020 [1]. As an illustration of the demonstrated method's utility, an epitope from the S protein of Hepatitis B virus (HBV) was amplified. Additionally, peptides, showing potentially pro-regenerative properties, derived from the angiopoietin-related growth factor (AGF) were designed and amplified. Here we present a dataset including: (i) detailed protocols for the purification of HBV and AGF – derived polyepitopic protein concatemers, (ii) sequences of the designed primers, vectors and recombinant constructs (iii) data on cytotoxicity, immunogenicity and stability of AGF-derived polypeptides.

  • Daylight Appraisal Classes For Achitecture Students A Survey Combined With A Practical Assessment For Educational Training Recommendations
    • Natalia Sokół
    • Marta Waczyńska
    • Justyna Martyniuk-Pęczek
    2020 Pełny tekst

    The main objectives of this article are: (i) to present the relations between architecture students' subjective assessment of daylight in classrooms and the objective evaluation of daylit conditions using daylight simulations tools, (ii) to formulate guidelines and recommendations on daylight appraisal methods and tools which may be useful in architectural training. The methodology used includes an evaluation of the results of the direct questionnaire and the computational simulations of the observed conditions. One hundred ninety-four architecture students form three different universities in Poland assessed daylight in 13 different classrooms. The questionnaire aimed to investigate relationships between daylight subjective assessment, students’ perception and daylight knowledge. This paper focuses only on the results of the subjective appraisal of daylit interior spaces and the objective evaluation of the investigated conditions. The simulations of Daylight Factor and Daylight Autonomy were carried out using various available software and the available climate and weather data (for DA). The key findings of the study are: Daylight appraisal part: (i) Daylight factor simulations results correspond with subjective students' assessments of daylight sufficiency within the rooms for eight out of 13 cases. (ii) The were no significant correlations found between the mean illuminances values and the subjective students' appraisals of daylight. The subjective description of daylight within the investigated classrooms was similar (medium) for all the sessions. (iii) The subjective perception of uniformity for task illumination was rated by observers as a medium, while the mean illuminance levels varied from 61 to 460 lx. Architectural training part: (iv) The use of advanced computer daylight simulations tools supports educational activities and aids architectural design, only if the students can comprehend the obtained results (v) Available informative packages should cover contemporary analysis daylight tools.

  • Debonding Size Estimation in Reinforced Concrete Beams Using Guided Wave-Based Method
    • Beata Zima
    • Rafał Kędra
    2020 Pełny tekst SENSORS

    The following paper presents the results of the theoretical and experimental analysis of the influence of debonding size on guided wave propagation in reinforced concrete beams. The main aim of the paper is a development of a novel, baseline-free method for determining the total area of debonding between steel rebar embedded in a concrete cover on the basis of the average wave velocity or the time of flight. The correctness of the developed relationships was verified during the experimental tests, which included propagation of guided waves in concrete beams with the varying debonding size, shape and location. The analysis of the collected results proved that guided waves can be efficiently used not only in the debonding detection, but also in an exact determining of its total area, which is extremely important in the context of the nondestructive assessment of the load capacity of the reinforced concrete structures. The undeniable advantage of the proposed method is that there are no requirements for any baseline signals collected for an undamaged structure. The paper comprises of the detailed step by step algorithm description and a discussion of both the advantages and disadvantages.

  • Decomposition of halogenated nucleobases by surface plasmon resonance excitation of gold nanoparticles
    • Telma S. Marques
    • Małgorzata Śmiałek-Telega
    • Robin Schürmann
    • Ilko Bald
    • Maria Raposo
    • Samuel Eden
    • Nigel J. Mason
    2020 Pełny tekst EUROPEAN PHYSICAL JOURNAL D

    Halogenated uracil derivatives are of great interest in modern cancer therapy, either as chemotherapeutics or radiosensitisers depending on their halogen atom. This work applies UV-Vis spectroscopy to study the radiation damage of uracil, 5-bromouracil and 5- uorouracil dissolved in water in the presence of gold nanoparticles upon irradiation with an Nd:YAG ns-pulsed laser operating at 532nm at dierent uences. Gold nanoparticles absorb light eciently by their surface plasmon resonance and can signicantly damage DNA in their vicinity by an increase of temperature and the generation of reactive secondary species, notably radical fragments and low energy electrons. A recent study using the same experimental approach characterized the ecient laser-induced decomposition of the pyrimidine ring structure of 5-bromouracil mediated by the surface plasmon resonance of gold nanoparticles. The present results show that the presence of irradiated gold nanoparticles decomposes the ring structure of uracil and its halogenated derivatives with similar eciency. In addition to the fragmentation of the pyrimidine ring, for 5-bromouracil the cleavage of the carbon-halogen bond could be observed, whereas for 5- uorouracil this reaction channel was inhibited. Locally-released halogen atoms can react with molecular groups within DNA, hence this result indicates a specic mechanism by which doping with 5-bromouracil can enhance DNA damage in the proximity of laser irradiated gold nanoparticles.

  • Decrease in Photovoltaic Module Efficiency Due to Deposition of Pollutants
    • Ewa Klugmann-Radziemska
    • Małgorzata Rudnicka
    2020 Pełny tekst IEEE Journal of Photovoltaics

    The deposition of pollutants on the surface of photovoltaic (PV) modules reduce the efficiency that can be achieved in given climatic conditions. This results in the loss of energy yield obtained from the solar installation. A number of factors determine the scale of this problem. The first of these is the amount of impurities deposited, the associated amount of precipitation, and the speed and direction of the wind. A second aspect is the type of pollution and the composition and structure of the sludge, which depends on the location of the installation. The type of installation, either stationary or sun tracking, is essential because the angle of inclination of modules, depending on the latitude, will determine the amount of dust deposited, especially for stationary installations. The observed decrease in efficiency of PV modules covered with dust equals 6–10% of the efficiency of a module free of impurities. This means that the user should maintain the module surface and schedule routine cleaning.

  • Decyzje optymalne z Solverem
    • Anna Baj-Rogowska
    2020

    Na rynku można odnaleźć wiele podręczników pomocnych w rozwijaniu kompetencji związanych z posługiwaniem się arkuszem kalkulacyjnym w praktyce menedżerskiej. Niewiele jest natomiast pozycji literaturowych pokazujących możliwości wykorzystania MS Solver do wspomagania decyzji. Niniejsza książka ma za zadanie wypełnić tę lukę. Jej celem jest przedstawienie możliwości dodatku Solver w procesie podejmowania decyzji optymalnych. Intencją Autorki było stworzenie podręcznika dla osób zainteresowanych samodzielną nauką pracy z MS Excel Solver. Niniejsze opracowanie składa się z trzech rozdziałów. Rozdział pierwszy zawiera teoretyczne podstawy wprowadzające do zagadnień podejmowania decyzji optymalnych. Przedstawiono w nim podstawowe pojęcia z tego zakresu, omówiono czym jest proces rozwiązywania problemów decyzyjnych ze szczególnym rozróżnieniem pomiędzy rozwiązywaniem problemów decyzyjnych a ich podejmowaniem. Drugi rozdział został dedykowany przedstawieniu funkcjonalności dodatku Solver wraz z omówieniem opcji ustawień i metod rozwiązań dostępnych w programie oraz raportów wyników, wrażliwości i granic. Na tak przygotowanej podbudowie teoretycznej w dalszej części rozdziału zaprezentowano praktyczne rozwiązanie krok po kroku prostego zadania decyzyjnego. Takie podejście przygotowuje Czytelnika do treści zawartych w rozdziale trzecim. Przedstawiono tutaj różnorodne i znacznie bardziej złożone problemy decyzyjne. Dobór przykładów ma na celu pokazanie potencjału Solvera.

  • Deep eutectic solvents vs ionic liquids: Similarities and differences
    • Justyna Płotka-Wasylka
    • Miguel De la Guardia
    • Vasil Andruch
    • Mária Vilková
    2020 Pełny tekst MICROCHEMICAL JOURNAL

    Deep eutectic solvents (DES) were introduced as an alternative to ionic liquids (IL) to overcome the drawbacks of IL solvents. However, some authors consider them to be a subclass of ILs. In contrast, other authors emphasize that these are by their nature independent, different groups of substances. Thus, the question arises: Which solvent group should DESs belong to? Maybe a new class should be added to the existing ones. The aim of this work is to attract the attention of researchers using DES in their studies to the need for a proper use of terms.

  • Deep Instance Segmentation of Laboratory Animals in Thermal Images
    • Magdalena Mazur-Milecka
    • Tomasz Kocejko
    • Jacek Rumiński
    2020 Pełny tekst Applied Sciences-Basel

    In this paper we focus on the role of deep instance segmentation of laboratory rodents in thermal images. Thermal imaging is very suitable to observe the behaviour of laboratory animals, especially in low light conditions. It is an non-intrusive method allowing to monitor the activity of animals and potentially observe some physiological changes expressed in dynamic thermal patterns. The analysis of the recorded sequence of thermal images requires smart algorithms for automatic processing of millions of thermal frames. Instance image segmentation allows to extract each animal from a frame and track its activity and thermal patterns. In this work, we adopted two instance segmentation algorithms, i.e., Mask R-CNN and TensorMask. Both methods in different configurations were applied to a set of thermal sequences, and both achieved high results. The best results were obtained for the TensorMask model, initially pre-trained on visible light images and finally trained on thermal images of rodents. The achieved mean average precision was above 90 percent, which proves that model pre-training on visible images can improve results of thermal image segmentation.

  • Deep learning based thermal image segmentation for laboratory animals tracking
    • Magdalena Mazur-Milecka
    • Jacek Rumiński
    2020 QIRT Journal

    Automated systems for behaviour classification of laboratory animals are an attractive alternative to manual scoring. However, the proper animals separation and tracking, especially when they are in close contact, is the bottleneck of the behaviour analysis systems. In this paper, we propose a method for the segmentation of thermal images of laboratory rats that are in close contact during social behaviour tests. For this, we are using thermal imaging – a technology that requires neither light nor human presence. The aim of the study was: (1) an efficiency analysis of deep learning based image segmentation algorithms for the need of laboratory rats images, (2) analysis of different methods of original thermal data conversion to grey scale images for the purpose of the segmentation, (3) evaluation of the image data range impact on segmentation results using deep learning networks. We have trained U-Net and V-Net architectures with images obtained from different temperature ranges. The results indicate, that networks trained on images containing a narrow range of temperature data equal to animals’ body temperature or even its part, are able to better perform the object segmentation than networks trained on the original data.

  • Deep learning for recommending subscription-limited documents
    • Grzegorz Chłodziński
    • Karol Woźniak
    2020 Pełny tekst

    Documents recommendation for a commercial, subscription-based online platform is important due to the difficulty in navigation through a large volume and diversity of content available to clients. However, this is also a challenging task due to the number of new documents added every day and decreasing relevance of older contents. To solve this problem, we propose deep neural network architecture that combines autoencoder with multilayer perceptron in a hybrid recommender system. We train our model using real-world historical data from commercial platform using interactions to capture user similarity and categorical document features to predict the probability of a user-document interaction. Our experimental results demonstrate the effectiveness of the proposed architecture. We plan to release our model in a commercial online platform to support a personalized user experience.

  • Deep Learning-Based Intrusion System for Vehicular Ad Hoc Networks
    • Li Fei
    • Zhang Jiayan
    • Song Jiaqi
    • Edward Szczerbicki
    2020 Pełny tekst CMC-Computers Materials & Continua

    The increasing use of the Internet with vehicles has made travel more convenient. However, hackers can attack intelligent vehicles through various technical loopholes, resulting in a range of security issues. Due to these security issues, the safety protection technology of the in-vehicle system has become a focus of research. Using the advanced autoencoder network and recurrent neural network in deep learning, we investigated the intrusion detection system based on the in-vehicle system. We combined two algorithms to realize the efficient learning of the vehicle’s boundary behavior and the detection of intrusive behavior. In order to verify the accuracy and efficiency of the proposed model, it was evaluated using real vehicle data. The experimental results show that the combination of the two technologies can effectively and accurately identify abnormal boundary behavior. The parameters of the model are self-iteratively updated using the time-based back propagation algorithm. We verified that the model proposed in this study can reach a nearly 96% accurate detection rate.

  • Defective TiO2 Core-Shell Magnetic Photocatalyst Modified with Plasmonic Nanoparticles for Visible Light-Induced Photocatalytic Activity
    • Zuzanna Bielan
    • Agnieszka Sulowska
    • Szymon Dudziak
    • Siuzdak Katarzyna
    • Jacek Ryl
    • Anna Zielińska-Jurek
    2020 Pełny tekst Catalysts

    In the presented work, for the first time, the metal-modified defective titanium(IV) oxide nanoparticles with well-defined titanium vacancies, was successfully obtained. Introducing platinum and copper nanoparticles (NPs) as surface modifiers of defective d-TiO2 significantly increased the photocatalytic activity in both UV-Vis and Vis light ranges. Moreover, metal NPs deposition on the magnetic core allowed for the effective separation and reuse of the nanometer-sized photocatalyst from the suspension after the treatment process. The obtained Fe3O4@SiO2/d-TiO2-Pt/Cu photocatalysts were characterized by X-ray diffractometry (XRD) and specific surface area (BET) measurements, UV-Vis diffuse reflectance spectroscopy (DR-UV/Vis), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). Further, the mechanism of phenol degradation and the role of four oxidative species (h+, e−, •OH, and •O2−) in the studied photocatalytic process were investigated

  • Deflated Preconditioned Solvers for Parametrized Local Model Order Reduction
    • Martyna Mul
    • Michał Mrozowski
    2020

    One of steps in the design of microwave filters is numerical tuning using full-wave simulators. Typically, it is a time-consuming process as it uses advanced computational methods, e.g. the finite-element method (FEM) and it usually requires multiple optimization steps before the specification goals are met. FEM involves solving a large sparse system of equations at many frequency points and therefore its computational cost is high. One of the ideas to speed up the numerical optimization is parametrized model-order reduction (PMOR). The key point in model order reduction, is that the original large sparse system of FE equations is replaced with a small and dense one, that can be solved at many frequency points with substantially smaller computational effort. PMOR yields in the parameter dependent reduced-order model which might be reused in subsequent optimization steps.

  • Deformation and Surface Color Changes of Beech and Oak Wood Lamellas Resulting from the Drying Process
    • Jacek Barański
    • Aleksandra Konopka
    • Tatiana Vilkovská
    • Ivan Klement
    • Peter Vilkovský
    2020 Pełny tekst BIORESOURCES

    The drying process was examined relative to parameters’ influence on the deformation and surface layer color changes of beech wood (Fagus sylvatica L.) and oak wood (Quercus robur L.). The goal was to analyze the impact of drying process conditions, wood and growth rings types, and load on the deformation and surface color changes of drying thin wooden elements. A further aim was to reduce the time of the lamella drying and minimize wood products defects. During each drying, 40 pieces of wood were dried, divided into two groups. For the first group, 30 pieces were dried under a uniformly distributed load of approximately 50 kg, while for the second group, 10 samples were dried without weight. The lamellas dried under load exhibited fewer cup, bow, and twist deformations than the lamellas dried without load. Cracks in the dried lamellas occurred comparably in those dried under and without load. Color changes in the specimens before and after drying were observed and measured. The differences in colorimetric parameters (a, b, and L) between wood without defects and with defects were less marked after drying than before drying. The color changes were only noticed in the surface layers of the specimens.

  • Degradation of ferritic X10CrAlSi18 stainless steel caused by slurry
    • Alicja Krella
    • Marta Buszko
    • Grzegorz Gajowiec
    2020 ENGINEERING FAILURE ANALYSIS

    The slurry erosion tests of ferritic X10CrAlSi18 steel were carried out using a slurry pot device. In order to investigate the erosion process, two series of tests were performed: first one with a constant impact velocity of 5 m/s, 7 m/s and 9 m/s and the second one, during which the impact velocity was changed after every exposure. During each test, an influence of test conditions on volume loss, surface hardness and roughness with exposure time was studied. The normalized erosion rate and erosion efficiency parameter increased linearly with velocity in the range between 5 and 9 m/s. Surface hardness increased exponentially with an exponent n = 0.27. The erosive efficiency parameter determined for tests carried out with variable impact velocity was higher than for tests with constant velocity. The erosion performance increased as the difference in consecutive impact velocity increased. At the beginning of slurry tests, surface hardness and roughness increased rapidly. A fluctuation in erosion rate and surface roughness was noted in the tests performed with variable impact velocity. The amplitudes of these fluctuations decreased with the test duration. Surface hardness influenced damage formed on the specimen’s surface. With increasing surface hardness, surface roughness (Ra parameter) decreased. For surface hardness over 280 HV flakes were formed on the specimen surface.

  • Degradation of Kinematic PPP of GNSS Stations in Central Europe Caused by Medium-Scale Traveling Ionospheric Disturbances During the St. Patrick’s Day 2015 Geomagnetic Storm
    • Mateusz Poniatowski
    • Grzegorz Nykiel
    2020 Pełny tekst Remote Sensing

    In solar cycle 24, the strongest geomagnetic storm took place on March 17, 2015, when the geomagnetic activity index was as high as -223 nT. To verify the impact that the storm had on the Global Navigation Satellite System (GNSS)’s positioning accuracy and precision, we used 30-s observations from 15 reference stations located in Central Europe. For each of them, we applied kinematic precise point positioning (PPP) using gLAB software for the day of the storm and, for comparison, for a selected quiet day (13 March 2015). Based on the conducted analyses, we found out that the position root mean square (RMS) values on the day of the geomagnetic storm were significantly high and amounted to several dozen centimeters. The average RMS for the altitude coordinates was 0.58 m between 12:00 and 24:00 (GPS time), and 0.37 and 0.26 m for directions North and East, respectively. The compromised accuracy level was caused by a sudden decrease in the number of satellites used for calculations. This was due to a high number of cycle slips (CSs) detected during this period. The occurrence of these effects was strictly correlated with the appearance of traveling ionospheric disturbances (TIDs). This was proven by analyzing changes in the total electron content (TEC) estimated for each station–satellite pair.

  • Degree of monopoly and market power vs. price flexibility in Polish economy: empirical analysis based on COICOP classification
    • Paweł Umiński
    2020 Pełny tekst Oeconomia Copernicana

    Research background: The issue of price flexibility is crucial in the economy both in the aspect of company theory and its macroeconomic consequences. In a number of publications, the sources of variable price flexibility are linked to the market power of enterprises as well as the market structure that has developed in a given branch. It is difficult to indicate empirical studies that would state clearly whether price flexibility depends on the degree of monopoly or the market power of enterprises. This paper concerns that particular field of study. Purpose of the article: The purpose of the paper is to present the statistical dependence of the degree of monopoly and market power vs. price flexibility in the economy. Methods: The analysis has been conducted using aggregated data concerning Polish economy in the period from 2001 to 2013, based on COICOP. The degree of monopoly indicator was the average number of companies in a given branch, following the classical models of market structures; the market power indicator was the average net revenue from sales of products per enterprise representing a given branch; the measure of price flexibility was the probability of price variation estimated using the Calvo pricing model. It is, therefore, a frequency-based approach to price flexibility. Statistical dependence was analyzed using the Spearman's rank and Kendall’s tau correlation coefficient and simple regression models. Findings & Value added: The outcomes indicate that in the case of Poland in the analyzed period there is no statistically significant relation between the degree of monopoly and price flexibility and also between the market power and price flexibility. Thus, the findings of the analysis support the studies which reject the assumption that higher degree of monopoly or higher market power of an enterprise is followed by less flexible prices.

  • Density functional LCAO calculations of vibrational modes and phonon density of states in the strained single-layer phosphorene
    • Krzysztof Pyrchla
    • Robert Bogdanowicz
    2020 Pełny tekst APPLIED SURFACE SCIENCE

    The paper presents an investigation of phosphorene under axial strain on the phonon density of states and vibrational modes. The studies were performed by means of density functional theory (DFT) within the linear combination of atomic orbitals (LCAO). The strained models were constructed using optimised supercell techniques. The vibrational mode spectra were estimated for strains applied for both the zigzag and armchair directions of phosphorene. This approach is an attractive candidate for the calculation the dynamical matrix of the system because its numerical complexity gradually increases together with the size of the analysed cell. The shift of peaks in the PDOS of black phosphorene is monotonic, and inversely proportional to the applied strain over the zigzag direction. This relation is valid for small strains (below 10%) of peaks corresponding to modes B2g and Ag2. For a strain applied over the armchair PDOS, the shifts are proportional to the strain. The peak shifts tend to become higher as the strain increases. This dependence is not monotonic, and is clearly more rapid for compressing strains. Moreover, the peaks shift slower for an armchair strain than for a zigzag strain, revealing its strong anisotropy.

  • Deodorization of model biogas by means of novel non-ionic deep eutectic solvent
    • Edyta Słupek
    • Patrycja Makoś
    • Jacek Gębicki
    2020 Pełny tekst Archives of Environmental Protection

    The paper presents new non-ionic deep eutectic solvent (DES) composed of natural and non-toxic components i.e. guaiacol, camphor and levulinic acid in 1:1:3 molar ratio as a promising absorbent for removal of selected volatile organic compounds (VOCs) including dichloromethane, toluene, hexamethyldisiloxane and propionaldehyde from model biogas. The affi nity of DES for VOCs was determined as vapour-liquid coeffi cients and the results were compared with several well-known DESs based on quaternary ammonium salt as well as n-hexadecane and water. For new DES, the absorption process was carried out under dynamic conditions. The results indicate that non-ionic DES has high affi nity and capacity for VOCs being comparable to n-hexadecane. In addition, absorbed VOCs could be easily desorbed from DES using activated carbon and absorbent could be re-use minimum five times without signifi cant loss of absorption capacity

  • DESIGN ANALYSIS OF HYBRID GAS TURBINE - FUEL CELL POWER PLANT IN STATIONARY AND MARINE APPLICATIONS
    • Tomasz Kwaśniewski
    • Marian Piwowarski
    2020 Pełny tekst Polish Maritime Research

    The paper concerns design analysis of a hybrid gas turbine power plant with a fuel cell (stack). The aim of this work was to find the most favorable variant of the medium capacity (approximately 50 MW) hybrid system. In the article, computational analysis of two variants of such a system was carried out. The analysis let to calculate capacity, efficiency of both variants and other parameters like flu gas temperature. The paper presents that such a hybrid cycles can theoretically achieve extremely high efficiency over 60%. The most favorable one was selected for further detailed thermodynamic and flow calculations. As part of this calculation, a multi-stage axial compressor, axial turbine, fuel cell (stack) and regenerative heat exchanger were designed. Then an analysis of the profitability of the installation was carried out, which showed that the current state of development of this technology and its prices make the project unprofitable. For several years, however, tendencies of decreasing prices of fuel cells have been observed, which allows to conclude that hybrid systems will start to be created. This may apply to both stationary and marine applications. Hybrid solutions related to electrical power transmission, including fuel cells, are real and very promising for smaller car ferries and shorter ferry routes.

  • Design Analysis of Micro Gas Turbines in Closed Cycles
    • Krzysztof Kosowski
    • Marian Piwowarski
    2020 Pełny tekst ENERGIES

    The problems faced by designers of micro-turbines are connected with a very small volume flow rate of working media which leads to small blades’ height and high rotor speed. In the case of gas turbines this limitation can be overcome by the application of a closed cycle with very low pressure at the compressor inlet (lower than atmospheric pressure). In this way we may apply a micro gas turbine unit of accepted efficiency to work in a similar range of temperatures and the same pressure ratios, but in the range of smaller pressure values and smaller mass flow rate. Thus, we can obtain a gas turbine of a very small output but of the efficiency typical of gas turbines with a much higher power. In the paper the results of the thermodynamic calculations of the turbine cycles are discussed and the designed gas turbine flow parts are presented. Suggestions of the design solutions of micro gas turbines for different values of power output are proposed. This new approach to gas turbine arrangement makes it possible to build a gas turbine unit of a very small output and a high efficiency. The calculations of cycle and gas turbine design were performed for different cycle parameters and different working media (air, nitrogen, hydrogen, helium, xenon and carbon dioxide).

  • Design and characterization of apatite La9.8Si5.7Mg0.3O26±δ-based micro-tubular solid oxide fuel cells
    • Sea-Fue Wang
    • Yung-Fu Hsu
    • Pu Hsia
    • Wei-Kai Hung
    • Piotr Jasiński
    2020 JOURNAL OF POWER SOURCES

    In this study, electrolyte-supported (Cell A) and anode-supported (Cell B) micro-tubular solid oxide fuel cells (SOFCs) based on the La9.8Si5.7Mg0.3O26±δ (LSMO) electrolyte is built through an extrusion and dip-coating processes. The formulations and process conditions for these cells are established and optimized. Both cell configurations show no visible delamination or cracking, and reaction zones and inter-diffusion of any species are absent at the interfaces of the multilayer structures. The micro-tubes LSMO and LSMO-NiO have a high flexural strength of ~70 MPa. Cell B with a 3.33 mm outer diameter, a 12 μm LSMO electrolyte layer, a ~300 μm LSMO-NiO functional anode layer, a 9 μm NiO current-collector layer, and a 44 μm La0.6Sr0.4Co0.2Fe0.8O3-δ cathode layer has superior electrochemical performances than does Cell A. The polarization resistance (Rp) value for Cell B accounts for 67.6% and 50.5% of the total resistance (Rt) value at 700 °C and 895 °C, respectively, suggesting that Rp dominates at low temperatures and ohmic resistance (Ro) and Rp values are equally important at high temperatures. Cell B's open-circuit voltages (OCVs) are slightly below the theoretical value due to poor sealing of cells. The maximum power densities (MPDs) of Cell B, increase with increasing operating temperature and are 0.12, 0.24, and 0.27 W cm−2 at 750 °C, 850 °C, and 895 °C, respectively. Compared to Cell A, Cell B displays lower OCV values but higher MPD (0.27 W cm−2 vs. 0.06 W cm−2 at 895 °C) due to its significantly lower Ro value, mainly due to the thin layer of LSMO electrolytes.

  • Design and Evaluation of the Platform for Weight-Shifting Exercises with Compensatory Forces Monitoring
    • Wiktor Sieklicki
    • Robert Barański
    • Szymon Grocholski
    • Patrycja Matejek
    • Mateusz Dyrda
    2020 Pełny tekst Communications in Computer and Information Science

    Details of a platform for the rehabilitation of people with severe balance impairment are discussed in the paper. Based upon a commercially available static parapodium, modified to fit force sensors, this device is designed to give a new, safe tool to physiotherapists. It is designed for the patients who cannot maintain equilibrium during a bipedal stance and need to hold to or lean on something during the rehabilitation. Visual, real-time information about weight distribution between left and right leg as well as the information about the force applied to the pillows supporting the patient's body is provided to the patient with help of a LED display. The control system allows registering forces applied by the patient to the device and analyze them after the therapy. The results of a preliminary evaluation of the device are presented in the paper with four healthy and one Cerebral Palsy ataxic participants. Two exercise scenarios are tested showing significant dependence between balance impairment and compensatory forces measured by the device, as well as a notable difference in how the subject strives for better results if the visual feedback is provided.

  • DESIGN AND THEORETICAL ANALYSIS OF A PROTOTYPE TILTING-PAD RADIAL BEARING WITH ADJUSTABLE CLEARANCE
    • Artur Olszewski
    • Grzegorz Żywica
    • Tomasz Żochowski
    2020 Pełny tekst TRIBOLOGIA

    The article introduces a design and analysis results of a prototype ORC (organic Rankine cycle) turbo generator rotor assembly of 300kW power, supported by tilting-pad bearings of original design. The calculations were performed for a prototype turbo generator rotor. The shaft of this machine is supported with two radial bearings, lubricated with an unusual lubricant – a low-boiling-point agent. The main objective of the presented research was to perform calculations verifying the feasibility of using hydrodynamic tilting-pad radial bearings with a low-viscosity lubricant to support a rather massive and high-speed rotor of the developed turbo generator and to determine the geometry and design of the bearings which would ensure optimal kinetostatic and dynamic properties of the rotating system, while simultaneously providing ease of assembly and smooth clearance adjustment.

  • Design aspects of a low-cost prosthetic arm for people with severe movement disabilities
    • Tomasz Kocejko
    • Radosław Węglarski
    • Tomasz Zubowicz
    • Jacek Rumiński
    • Jerzy Wtorek
    • Krzysztof Armiński
    2020

    In this paper the main aspects of mechanical design behind the low-cost prosthetic arm are presented. The fundamentals of a proper design has been defined to obtain functional 3D printed 5 degree of freedom (DOF) prosthesis. The designed prosthetic arm is a part of the hybrid interface with eye tracking movement control. The main focus was to create affordable but usable prosthesis which corresponds in size and weights to the human arm. The iterative process (starting from the final segment of the arm) was used to design fully functioning arm. All the elements were evaluated regarding total weight and the maximum load that can be carried by the arm. The result of this work is a prototype that weighs below 6kg and has a range of motion comparable to the human's arm. Final product is able to freely move an object of a total weight of 1 kg. All the mechanical parts of the designed arm were 3D printed which therefore presented construction can be adopted by people with different disabilities and (when connected to interfaces like EEG, EMG or eye tracking) provide support in everyday life activities.

  • DESIGN LOGICAL LINGUISTIC MODELS TO CALCULATE NECESSITY IN TRUCKS DURING AGRICULTURAL CARGOES LOGISTICS USING FUZZY LOGIC
    • Ievgen Medvediev
    • Dmitriy Muzylyov
    • Natalya Shramenko
    • Pavlo Nosko
    • Peter Eliseyev
    • Vitalii Ivanov
    2020 Pełny tekst Acta Logistica

    : The study is aimed to develop the logic-linguistic models to design a number of rules for the correct calculation of the vehicles needed, taking into account the technical, technological, and weather and climate conditions of the harvesting and transport complex. The article has shown that the construction of the design of logic-linguistic models was not performed earlier to solve the problem of the agro-industrial production transportation support, considering the opportunity of forecasting size of influences of the weather and climatic factors on improving the productivity of the harvesting and transport complex elements. It is determined that the experience of applying the fuzzy logic theory in many practice situations confirms the universality of the mathematical apparatus. This toolkit provides better results than classical approaches (set theory, probability theory). This aspect indicates the expediency of the chosen mathematical apparatus for solving the tasks. The article using fuzzy logic explores the relationship and interdependence of technical, technological factors and weather and climate conditions for modeling transport support in harvesting and transport complex. Fuzzification of the parameters is carried out, based on the compiled equations using trapezoidal and triangular membership functions. The set of rules necessary for the creation of logical-linguistic models (LLM) for each factor has been arranged. LLMs were developed for dependent parameters, which will allow further modeling of the transport support of the harvesting and transport complex in the Fuzzy Logic Toolbox application of the MATLAB package.

  • Design of battery charging system update for glider launcher
    • Wojciech Rosiński
    • Szymon Potrykus
    • Michał Michna
    2020 Pełny tekst Archives of Electrical Engineering

    This paper presents an innovative solution for increasing life of lead-acid batteries used in a glider launcher. The study is focused on upgrading a charging system instead of a costly full replacement of it. Based on literature review, the advanced three-stage charging profile was indicated. The new topology of the power converter was proposed and a simulation model was developed. A simulation study was performed which leads to a conclusion that the suggested solution can be successfully applied to the studied device. As a result, the conclusion of this work is the recommendation for modification of the launching system with an additional converter enabling 3 stage charging.

  • Design of new cholinesterase inhibitors based on phosphorus analogs of tacrine as potential anti-Alzheimer’s disease agents
    • Maja Przybyłowska
    • Krystyna Dzierzbicka
    • Iwona Inkielewicz-Stępniak
    2020

    Based on the analysis of the determined free binding energy (using the AutoDock Vina 1.1.2 docking program), the most potent cholinesterase inhibitors were selected. Moreover, studies of 3D visualization of the results of molecular modeling led to the identification of potential sites for the interaction of new potential inhibitors with amino acid residues building active sites of investigated cholinesterases.

  • Design of optimal state feedback controller with observer for multidimensional electrical system
    • Robert Piotrowski
    • Maciej Szafrański
    • Konrad Żuk
    2020 Pełny tekst Przegląd Elektrotechniczny

    From the control point of view, two-input-two-output RC electrical system is a linear and multidimensional system. In this paper, integral control and closed-loop observer are verified whether they can be used and designed. To verify this, Kalman tests are made. These structures are presented and discussed. Integral Control is tested with some base disturbances impact and checked whether it can handle them. The estimated values from the observer are compared with the original states. Simulation tests and real tests of control systems are presented.

  • Design of poroelastic wearing course with the use of direct shear test
    • Dawid Ryś
    • Piotr Jaskuła
    • Marcin Stienss
    • Cezary Szydłowski
    2020 Pełny tekst

    Poroelastic Road Surfaces (PERS) are characterized by porous structure with at least 20% of air void content and stiffness almost 10 times lower than typical asphalt course. Such properties enable noise reduction up to 12 dB in comparison to SMA 11 mixture. However, the main disadvantage of previously used poroelastic mixtures, based on resin type binders, was their low durability, which resulted in raveling and delamination from the lower layer. This paper presents initial results obtained for new type of PERS mixture, based on highly modified bitumen as a binder instead of resin type binder. The direct shear test was applied to estimate resistance of the mixture to raveling as well as to evaluate interlayer bond quality. Observations of first short test sections with different compositions of new PERS mixtures yielded promising results.

  • Design of power cable lines partially exposed to direct solar radiation – special aspects
    • Stanisław Czapp
    • Seweryn Szultka
    • Adam Tomaszewski
    2020 Pełny tekst ENERGIES

    Power cable lines are usually buried in the ground. However, in some cases, their ending sections are mounted along the supports of overhead lines. This leads to a situation where the cables are exposed to direct solar radiation and, consequentially, overheat. The paper presents the advanced computer modelling of power cables’ heating, considering their insolation as well as the effect of wind. The temperature and current-carrying capacity of power cables – during exposure to direct solar radiation – are evaluated. An effective method of limiting the unfavourable impact of the sun is discussed. In the presence of solar radiation, the proposed method enables a significant increase in the power cables current-carrying capacity.

  • Design of Resilient Vehicle-to-Infrastructure Systems
    • Jacek Rak
    • Magnus Jonsson
    • Alexey Vinel
    • Karol Jurczenia
    2020

    Vehicular ad hoc networks (VANETs) have recently gained noticeable attention due to advantages in improving road traffic safety, shaping the road traffic and providing infotainment opportunities to travellers. However, transmission characteristics following from the IEEE 802.11p standard and the high mobility of VANET nodes remarkably reduce the lifetime, reach and capacity of wireless links, and often lead to simultaneous disruptions of communications at multiple links. In this chapter, we present a set of solutions to enhance the performance of VANETs (which can be applied independently of particular applications) concerning (a) design of the VANET infrastructure (location of road-side units—RSUs and gateways), (b) communications along vehicle-to-infrastructure (V2I) links and (c) resilience of VANET services to malicious human activities.

  • Design, synthesis and high antitumor potential of new unsymmetrical bisacridine derivatives towards human solid tumors, specifically pancreatic cancers and their unique ability to stabilize DNA G-quadruplexes
    • Ewa Paluszkiewicz
    • Barbara Horowska
    • Barbara Borowa-Mazgaj
    • Grażyna Peszyńska-Sularz
    • Jolanta Paradziej-Łukowicz
    • Ewa Augustin
    • Jerzy Konopa
    • Zofia Mazerska
    2020 EUROPEAN JOURNAL OF MEDICINAL CHEMISTRY

    New promising unsymmetrical bisacridine derivatives (UAs), have been developed. Three groupsincluding 36 compounds were synthesized by the condensation of 4-nitro or 4-methylacridinone, imi-dazoacridinone and triazoloacridinone derivatives with 1-nitroacridine compounds linked with anaminoalkyl chain. Cytotoxicity screening revealed the high potency of these compounds against severaltumor cell lines. Particularly, imidazoacridinone-1-nitroacridine dimers strongly inhibited pancreaticPanc-1, Mia-Pa-Ca-2, Capan-2 and prostate cancer DU-145 cell growth. The studied compounds showedvery strong antitumor activity (T/C>300%) against Walker 256 rat adenocarcinoma. The selected 26 UAswere tested against 12 human tumor xenografts in nude mice, including colon, breast, prostate andpancreatic cancers. The studies on the molecular mechanism of action demonstrated that these un-symmetrical dimers significantly responded to the presence of G-quadruplex not to dsDNA. Structure-activity relationships for UAs potency to G-quadruplex stabilization indicated that thermal stability ofthis drug-G-quadruplex complex depended not only on the structure of heterocyclic rings, but also onthe properties of dialkylamino chains of the ring linkers. In conclusion, the presented studies identifiedthe new group of effective antitumor agents against solid human tumors, particularly pancreatic Panc-1,BxPC-3 and Mia-Pa-Ca-2 and strongly indicated their distinctive interactions with DNA. In contrast tomonomers, G-quadruplex not dsDNA is proposed to be thefirst molecular target for these compounds.

  • Design thinking (DT) for the design and planning education of engineer-architects
    • Dorota Kamrowska-Załuska
    • Tomasz Parteka
    2020 Pełny tekst World Transactions on Engineering and Technology Education

    Engineers are facing new challenges connected with globalisation, digitisation and the increased complexity of the design process. This calls for new, more interdisciplinary and user-oriented approaches to problem- solving. In this article, the authors analyse design thinking (DT) as a method to support the education of engineers specialising in architecture and urban planning. Identified in this study are the opportunities this method offers to solve design and planning problems, as well as the limitations of the method. It is based on experience gained, while conducting regional and urban planning courses for engineers in the Faculty of Architecture at Gdańsk University of Technology (FA-GUT). Gdańsk, Poland, The design thinking method is not a remedy for all design problems, but the user-centric, iterative and experimental approach that can help to prepare future professionals to conduct participatory design in the changing conditions of the modern world.

  • Designing control strategies of aeration system in biological WWTP
    • Robert Piotrowski
    • Tomasz Ujazdowski
    2020 Pełny tekst ENERGIES

    The paper presents the complete design processes of a novel aeration control systems in the SBR (Sequencing Batch Reactor) wastewater treatment plant (WWTP). Due to large energy expense and high influence on biological processes, the aeration system plays a key role in WWTP operation. The paper considers the aeration system for a biological WWTP located in the northeast of Poland. This system consists of blowers, the main collector pipeline, three aeration lines with different diameters and lengths, and diffusers. Classical control systems applied for this type of installation are based on PID (Proportional–Integral–Derivative) controllers, the settings of which are often found experimentally. The article presents the optimization of these settings and the design of an alternative control algorithm – the fuzzy controller.

  • Designing of Parking Spaces on Parking Taking into Account the Parameters of Design Vehicles
    • Miroslava Mikusova
    • Jamshid Abdunazarov
    • Joanna Żukowska
    • Juraj Jagelcak
    2020 Pełny tekst Computation

    Nowadays, in all cities, there is an acute problem of a lack of parking spaces. The number of vehicles is constantly increasing not only in big cities and megacities, but also in small towns of the country, and there are not enough parking places—the pace of solving the problem is several times slower than the growth rate of transport among citizens. The paper is dedicated to the determination of an optimal size of a parking place for design vehicles in a parking space as an element of roads. In the example of passenger cars and trucks, the optimal number of parking places is presented. The results of the research on the dimensioning of parking spaces serve as recommendations and can be used for the design of objects of transportation infrastructure. According to the research, authors introduce the term “design vehicle” and provide its definition. They also figure out optimal parameters for each design vehicle and recommend a special template for designing parking places.

  • DESIGNING OF PARKING SPACES TAKING INTO ACCOUNT THE PARAMETERS OF DESIGN VEHICLES IN RUSSIA
    • Miroslava Mikusova
    • Jamshid Abdunazarov
    • Joanna Żukowska
    • Alisher Usmankulov
    2020 Pełny tekst Communications - Scientific Letters of the University of Zilina

    Nowadays, in all the cities, there is an acute problem of a lack of parking spaces. The number of vehicles are becoming more and more larger, not only in megacities, but in small cities of the country, as well and there are no more parking places - the pace of solving the problem is several times slower than the rate of the transport growth among the citizens. The article is dedicated to the determination of the optimum sizes parking place for designing vehicles on a parking space, which is an element of the roads. The optimum amount parking places are determined on examples of the passenger cars and trucks. The results of research on dimensioning of parking spaces and recommendations to use the results for design of objects of transportation infrastructure are presented. According to the research, authors included the term "design vehicle" and gave its definition. The authors developed a template for 7 types of design vehicles and their sizes and also recommended sizes for longitudinal parking for each of their design vehicles. The optimum parking plot angles are determined, as well.

  • Design-oriented computationally-efficient feature-based surrogate modelling of multi-band antennas with nested kriging
    • Sławomir Kozieł
    • Anna Pietrenko-Dąbrowska
    2020 Pełny tekst AEU-INTERNATIONAL JOURNAL OF ELECTRONICS AND COMMUNICATIONS

    Design of modern antenna structures heavily depends on electromagnetic (EM) simulation tools. EM analysis provides reliable evaluation of increasingly complex designs but tends to be CPU intensive. When multiple simulations are needed (e.g., for parameters tuning), the aggregated simulation cost may become a serious bottleneck. As one possible way of mitigating the issue, the recent literature fosters utilization of faster representations, or surrogates, of the system at hand. Notwithstanding, conventional models are severely affected by the curse of dimensionality. In practice, modelling of antenna structures described by no more than a few parameters over narrow parameter ranges is possible. In the context of the structural complexity of modern antennas, this is hardly acceptable. This paper presents a novel technique for cost-efficient design-oriented modelling of multi-band antennas. Our approach integrates a recently reported nested kriging framework and the response feature technology. This combination enables rendering of reliable surrogates valid within broad ranges of geometry parameters while using small training data sets. Benchmarking against conventional modelling methods demonstrates superiority of the proposed framework in terms of both the predictive power of the surrogate and its setup cost. Design applications for antenna optimization are discussed as well.

  • Design-oriented modeling of antenna structures by means of two-level kriging with explicit dimensionality reduction
    • Sławomir Kozieł
    • Anna Pietrenko-Dąbrowska
    2020 AEU-INTERNATIONAL JOURNAL OF ELECTRONICS AND COMMUNICATIONS

    The employment of full-wave electromagnetic (EM) analysis is a practical necessity in the design of contemporary antenna structures. This is because simpler models are generally not available or of limited accuracy. At the same time, EM-based design is computationally expensive. Consequently, the ways of accelerating tasks such as parametric optimization or uncertainty quantification have to be sought. A possible workaround that has been gaining popularity over the recent years is utilization of fast surrogates. Among these, data-driven models are the most popular due to their versatility and easy handling. Notwithstanding, the curse of dimensionality and utility requirements (e.g., having the surrogate valid over broad ranges of geometry and operating parameters) limit the applicability of conventional approximation approaches to antenna modeling. Recently proposed performance-driven methods, especially the nested kriging framework, allow for going beyond the capability of the standard techniques. This is achieved by an appropriate confinement of the model domain, defined to contain only high-quality designs with respect to the selected performance figures. This paper proposes a novel approach, which combines the main idea of the nested kriging, specifically, the first-level model as a tool for constructing the domain-defining manifold, as well as principal component analysis to reduce the domain dimensionality in an explicit manner. Comprehensive benchmarking using three antenna structures indicates superiority of our methodology over conventional techniques, but also nested kriging, in terms of the achievable predictive power. The latter is obtained without compromising design utility of the model as demonstrated through application case studies.

  • Design-Oriented Two-Stage Surrogate Modeling of Miniaturized Microstrip Circuits with Dimensionality Reduction
    • Sławomir Kozieł
    • Anna Pietrenko-Dąbrowska
    • Muath Al-hasan
    2020 Pełny tekst IEEE Access

    Contemporary 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 parametric optimization and uncertainty quantification. These can be accelerated using fast replacement models, among which the data-driven surrogates are the most popular. Notwithstanding, a construction of approximation models for microwave components is hindered by the dimensionality issues as well as high nonlinearity of system characteristics. A partial alleviation of the mentioned difficulties can be achieved with the recently reported performance-driven modeling methods, including the nested kriging framework. Therein, the computational benefits are obtained by appropriate confinement of the surrogate model domain, spanned by a set of pre-optimized reference designs, and by focusing on the parameter space region that contains high quality designs with respect to the considered performance figures. This paper presents a methodology that incorporates the concept of nested kriging and enhances it by explicit dimensionality reduction based on spectral decomposition of the reference design set. Extensive verification studies conducted for a compact rat-race coupler and a three-section impedance matching transformer demonstrate superiority of the presented approach over both the conventional techniques and the nested kriging in terms of modeling accuracy. Design utility of our surrogates is corroborated through application cases studies.

  • Detection and Imaging of Debonding in Adhesive Joints of Concrete Beams Strengthened with Steel Plates Using Guided Waves and Weighted Root Mean Square
    • Erwin Wojtczak
    • Magdalena Rucka
    • Magdalena Knak
    2020 Pełny tekst Materials

    Strengthening of engineering structures is an important issue, especially for elements subjected to variable loads. In the case of concrete beams or slabs, one of the most popular approaches assumes mounting an external reinforcement in the form of steel or composite elements by structural adhesives. A significant disadvantage of adhesive joints is the lack of access to the adhesive film for visual condition assessment, thus, there is a need for non-destructive diagnostics of these kinds of connections. The aim of this paper was the identification and visualization of defects in adhesive joints between concrete beams and steel plates using the guided wave propagation technique. The initial theoretical and numerical analyses were performed. The experimental wave field was excited and measured by the scanning laser Doppler vibrometry. The collected signals were processed by the weighted root mean square (WRMS) calculation. As a result, 2-D damage maps were obtained. The numerical simulations were performed to corroborate the experimental results. The results showed that the guided waves could be successfully applied in non-destructive diagnostics of adhesive joints between concrete and steel elements. However, the quality of damage visualizations strongly depended on the location of excitation.

  • Detection and size estimation of crack in plate based on guided wave propagation
    • Beata Zima
    • Rafał Kędra
    2020 Pełny tekst MECHANICAL SYSTEMS AND SIGNAL PROCESSING

    The paper presents results of the comprehensive theoretical and experimental investigation of crack detection in metallic plate using guided wave propagation. The main aim of the paper is to develop the novel method which would allow for linear crack size estimation with the use of minimal number of the transducers. In general, there exists the relation between length of the propagation path and the wave amplitude value. However, we have shown that the amplitude value can be also influenced by the interaction with the damage. The meaningful differences in the amplitudes of waves reflected from various damage zones (the end and middle point) have become the foundation of the novel algorithm of line-crack detection. All stages of the algorithm have been described in detail and then the experimental tests were conducted. The experimental investigation involved crack detection and its size estimation for four different configurations of piezo transducers. Each configuration consisted of one actuator and three sensors, what which so far was the minimum number of sensors for point damage detection. The damage maps created on the basis of the collected time-domain signals visualized the exact crack orientation in each case. It has been revealed that the developed algorithm allows also for determining the crack size when the configuration of the transducers is designed properly.

  • Detection, identification and determination of chiral pharmaceutical residues in wastewater: Problems and challenges
    • Aysegul Dogan
    • Justyna Płotka-Wasylka
    • Dagmara Kempińska-Kupczyk
    • Jacek Namieśnik
    • Agata Kot-Wasik
    2020 Pełny tekst TRAC-TRENDS IN ANALYTICAL CHEMISTRY

    Chiral pharmaceuticals (CPs) are widely used in different areas of human life, thus they are frequentlydetected in different ecosystems. However, before CPs reach the environment, wastewater is subjected todifferent treatment processes in order to remove them. Nevertheless, such processes may affect thechirality of CPs, thus it is very important to monitor CP levels during the wastewater treatment.This review addresses the present state of knowledge concerning the input, occurrence, fate and ef-fects of CPs in the environment. It focuses primarily on wastewater analysis, problems and challengesconnected with trace levels of CP enantiomers and highly complex matrices of samples. Analytical ap-proaches used in detection, identification and determination of enantiomers are presented. The appli-cation of the results of wastewater analysis to obtain information on the population's health andbehaviour has been included and discussed. Moreover, the prospects of the future trends in greenenantiomeric analysis are described.

  • Detection of debonding in reinforced concrete beams using ultrasonic transmission tomography and hybrid ray tracing technique
    • Monika Zielińska
    • Magdalena Rucka
    2020 Pełny tekst CONSTRUCTION AND BUILDING MATERIALS

    This paper concerns inspection of reinforced concrete elements, with particular emphasis on assessing the quality of the adhesive connection between steel and concrete. A novel theoretical model was developed to determine the paths of transmitted, refracted and reflected elastic waves as well as a creeping wave propagated along the inclusion surface. Imaging the internal structure of tested beams was based on wave propagation measurements carried out on their surface and computed tomography. The ray tracing was performed by the hybrid approach as a combination of the network theory and the ray bending methods. The obtained results indicated a great potential of ultrasonic tomography in detection of debonding in reinforced concrete structures.

  • DETERMINATION OF ADDITIONAL TENSION IN TOWED STREAMER CABLE TRIGGERED BY COLLISION WITH UNDERWATER MOVING OBJECT
    • Vladimir Blintsov
    • Konstantin Trunin
    • Wiesław Tarełko
    2020 Pełny tekst Polish Maritime Research

    The paper deals with issues connected with the behaviour of a streamer cable towed by a survey seismic vessel when the cable undergoes a strike triggered by collision with an underwater moving object. The consequences of such collisions may be both threat to the life of marine animals or damage to underwater units and large economic losses suffered by vessel owners. The risk of such collisions has increased over the last years as a result of increased offshore seismic survey operations. Therefore, a towed streamer should be very robust. To assure its robustness, we should know the deformation mechanism of a single streamer cable. This in turn requires the development of an appropriate mathematical model of such a phenomenon. In particular, the paper presents the characteristics of seismic survey vessels and streamers; an analysis of collisions that have occurred in the past; a statement of the problem, and a computer-aided system supporting simulation of the cable behaviour. To obtain all the necessary design parameters regarding the deformation mechanism of a streamer cable, we set up a dedicated computer-aided system that supports their calculation.

  • Determination of aminoglycoside antibiotics: current status and future trends
    • Marta Glinka
    • Wojciech Wojnowski
    • Andrzej Wasik
    2020 Pełny tekst TRAC-TRENDS IN ANALYTICAL CHEMISTRY

    The use of aminoglycoside antibiotics is prevalent in medicine and agriculture. Their overuse increases their mobility in the environment, resulting in a need for reliable methods for their determination in a variety of matrices. However, the properties of aminoglycosides, in particular their high polarity, make the development of such methods a non-trivial task, inciting researchers to tackle this complex issue from different angles. The necessity to determine aminoglycosides in complex matrices and at low concentration levels requires the development of relatively elaborate sample preparation methods and the use of selective and sensitive detection techniques. Various modes of liquid chromatography coupled with tandem mass spectrometry are usually the analytical methods of choice. However, the recent developments in techniques such as bioassays, quantum dot-based colourimetric applications and various aptasensors point towards the development of more easily accessible and user-friendly point-of-need tests for screening applications in food control and environmental monitoring. This review summarizes the state-of-the-art in sample preparation protocols and the determination of aminoglycosides using various techniques and outlines the future trends with an emphasis placed on the novel and emerging solutions in this area.

  • Determination of bromhexine and its metabolites in equine serum samples by liquid chromatography – Tandem mass spectrometry: Applicability to the elimination study after single oral dose
    • Emilia Waraksa
    • Katarzyna Owczarek
    • Paweł Kubica
    • Ewa Kłodzińska
    • Mariusz Ozimek
    • Robert Wrzesień
    • Barbara Bobrowska-Korczak
    • Jacek Namieśnik
    2020 Pełny tekst JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES

    Bromhexine (BH), expectorant used in the treatment of respiratory disorders associated with viscid or excessive mucus, is not permitted for use in the competing horse by many authorities in horseracing and Olympic disciplines. Metabolic studies are of the great importance in anti-doping field because they allow for updating the selection of the most appropriate markers for prohibited substances, such as metabolites present at higher concentration levels and/or lasted for a longer period of time in biological samples than a parent drug. This study describes LC-MS/MS-based method for simultaneous determination of BH and its metabolites, including 4-(2-amino-3,5-dibromobenzylamino)cyclohexanol (4-HDMB), 3-(2-amino-3,5-dibromobenzylamino)cyclohexanol (3-HDMB), in equine serum samples. The 2-(2-amino-3,5-dibromobenzylamino)cyclohexanol (2-HDMB) was monitored as well. The assay was validated in terms of linearity (R2 greater than 0.9951), intra- and inter-assay accuracy (91.6 – 109.1%) and precision (CV < 9.6%) as well as recovery (94.8 – 105.65%). The LODs were 0.0052, 0.0053, 0.0056 and 0.0043 ng/mL for BH, 2-HDMB, 3-HDMB and 4-HDMB, respectively. The developed method was applied to determine the time curses of BH and its metabolites concentrations in equine serum collected for 95.25 h following a single oral administration of BH to two healthy mares (in dose of 0.8 mg/kg). The parent drug was found at higher concentration levels than 3-HDMB (major metabolite) and 4-HDMB (minor metabolite), however, both BH metabolites lasted for a longer period of time in equine serum than the parent drug. Thus, both metabolites of BH can be considered as BH abuse markers.

  • Determination of energy-transfer distributions in ionizing ion-molecule collisions
    • Suvasthika Indrajith
    • Ewa Erdmann
    • Jacopo Chiarinelli
    • Alicja Domaracka
    • Marta Łabuda
    • Lorenzo Avaldi
    • Manuel Alcami
    • Nestor F. Aguirre
    • Sergio Díaz-Tendero
    • Paola Bolognesi
    • Patrick Rousseau
    • Bernd Alan Huber
    2020 Pełny tekst Journal of Physics : Conference Series

    The main objective of this study is to determine the energy transfer occuring in ion-molecule collisions. In order to solve this problem, we followed two approaches; the first one by validating a purely experimental method and the second one by testing a new theoretical model M3C (Microcanonical Metropolis Monte Carlo).