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  • Fast-response optoelectronic detection of explosives’ residues from the nitroaromatic compounds detonation: field studies approach
    • Jacek Wojtas
    • Robert Bogdanowicz
    • Agata Kamieńska-Duda
    • Beata Pietrzyk
    • Michał Sobaszek
    • Piotr Prasuła
    • Anna Dettlaff
    • Krzystof Achtenberg
    2020 Pełny tekst MEASUREMENT

    We are presenting an application of optoelectronic nitrogen dioxide (NO2) analyzer based on cavity enhanced absorption spectroscopy in the detection of traces of explosives after detonation. It has been shown that the analyzer using blue-violet laser is able to detect explosive residues after the detonation of various amounts of nitroaromatic compounds (75g-1kg) with higher efficiency than the HPLC soil sample testing equipment, which is the common standard in the analysis of explosives. Field studies have shown that it provided quick results, the amplitudes of which were about 8 dB despite the fact that NO2 in the air was 3 orders of magnitude smaller than explosives found in soil. The NO2 concentration after an explosion of different explosives at the distance of up to 20 m from the crater was 21-137 ppb, which was also dependent on the time between the explosion and the measurement, temperature and humidity of the atmospheric air and wind speed.

  • Fault Diagnostics in PEMFC Stacks by Evaluation of Local Performance and Cell Impedance Analysis
    • Jens Mitzel
    • J. Sanchez‐Monreal
    • D. Garcia‐Sanchez
    • P. Gazdzicki
    • M. Schulze
    • F. Häußler
    • Jurgen Hunger
    • G. Schlumberger
    • Ewa Janicka
    • Michał Mielniczek
    • Łukasz Gaweł
    2020 FUEL CELLS

    Starvation, flooding, and dry‐out phenomena occur in polymer electrolyte membrane fuel cells (PEMFCs), due to heterogeneous local conditions, material inhomogeneity, and uneven flow distribution across the single cell active area and in between the individual cells. The impact of the load level and air feed conditions on the performance was identified for individual single cells within a 10‐cell stack. Analysis of the current density distribution across the active area at the cell level was correlated with electrochemical impedance spectroscopy to enable operando fault diagnostic without any impact of the applied analytical tools on the single cell behavior. Moreover, the combination of both technologies allows in‐depth analysis of fault mechanisms in fuel cell single cells with improved sensitivity. Current density distribution and the quantitative assessment of the performance homogeneity demonstrated high sensitivity to small humidity changes and allow the detection of critical events, such as dry‐out in single cells. Impedance analysis is more sensitive regarding polarization and diffusion limitations and allows detection of cell flooding. The combination of both techniques is required for reliable identification of air starvation faults.

  • Fault Loop Impedance Measurement in Circuits Fed by UPS and Principle of Safety Protection
    • Jacek Katarzyński
    • Marek Olesz
    2020 Pełny tekst Sustainability

    This paper indicates a significant problem of uncertainty of fault loop impedance (FLI) measurement in circuits powered from uninterruptible power supply (UPS) (double-conversion AC-DC-AC). The correctly determined value of this impedance, related to the short-circuit current disconnection time and to the reference value, is one of the most important elements that determines the approval of an electrical installation and its receivers for operation. To define the principles of FLI measurement, several hundred measurements of the short-circuit loop impedance in the circuits fed by the UPS, in various UPS operation modes and with various FLI instruments, were made, which allowed for the definition of measurement rules that reduce the error in assessing the effectiveness of protection against electric shock by automatic disconnection of supply. Based on the analysis of voltage and current waveforms recorded during the real short-circuit tests in the circuit fed by the UPS, a proprietary algorithm for determining the short-circuit loop impedance has been proposed.

  • Faults and Fault Detection Methods in Electric Drives
    • Patrick Strankowski
    • Jarosław Guziński
    2020

    The chapter presents a review of faults and fault detection methods in electric drives. Typical faults are presented that arises for the induction motor, which is valued in the industry for its robust construction and cost-effective production. Moreover, a summary is presented of detectable faults in conjunction with the required physical information that allow a detection of specific faults. In order to address faults of a complete drive system, characteristic failures of the mechanical part of the drive system are as well presented. Furthermore, the physical forces, which arise during specific faults (i.e. centrifugal, kinematic) are presented along with dominant harmonics in the frequency spectrum. These dominant harmonics are especially important for the determination of a malfunction of the drive. The detection of the particular could be performed with signal processing methods which are tabular summarized for introduction purposes. In order to cover a further industry interest, a cost-effectiveness relation is presented, which describes whether a diagnostic system is appreciative or not. Moreover, most important international standards regarding the safety, health for human and machinery are summarized that are required to be fulfilled in every industrial application. The next subsection is dedicated to the presentation of fault detection methods that include a review of conventional methods for monitoring the conditions of the electric machine. That includes the monitoring of variables that are based on electrical, chemical, mechanical and thermal changes in the induction motor. The last subsection considers the fault detection methods, which are based on utilization of mathematical models. In this kind of fault detection, the model description is utilized to identify changes in the drive system, which then can be used for a potential fault identification procedure. Such mathematical constructs are mainly based on observer, Kalman filters or neural networks. The chapter is concluded with a short summary of the presented sections.

  • Feasibility Study GaN Transistors Application in the Novel Split-Coils Inductive Power Transfer System with T-Type Inverter
    • Viktor Shevchenko
    • Bohdan Pakhaliuk
    • Oleksandr Husev
    • Oleksandr Veligorskyi
    • Deniss Stepins
    • Ryszard Strzelecki
    2020 Pełny tekst ENERGIES

    A promising solution for inductive power transfer and wireless charging is presented on the basis of a single-phase three-level T-type Neutral Point Clamped GaN-based inverter with two coupled transmitting coils. The article focuses on the feasibility study of GaN transistor application in the wireless power transfer system based on the T-type inverter on the primary side. An analysis of power losses in the main components of the system is performed: semiconductors and magnetic elements. System modeling was performed using Power Electronics Simulation Software (PSIM). It is shown that the main losses of the system are static losses in the filter inductor and rectifier diodes on the secondary side, while GaN transistors can be successfully used for the wireless power transfer system. The main features of the Printed Circuit Board (PCB) design of GaN transistors are considered in advance

  • Feedback Control of Multiphase Induction Machines with Backstepping Technique
    • Marcin Morawiec
    • Patrick Strankowski
    • Arkadiusz Lewicki
    • Jarosław Guziński
    • Filip Wilczyński
    2020 IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS

    The paper presents the control possibility of five phase induction machines. In the proposed solution the machine model vector form is not transformed to the (dq)-coordinate system, that is connected to rotor flux vector, but utilizes the stationary system ( αβ ). Moreover, the nonlinear model linearization is based on demonstrated nonlinear variables transformation for i-orthogonal ( αβ )(n) planes. By introducing the backstepping approach, the independent stabilization of electromagnetic torque and rotor flux in each plane is obtained. A practical stability analysis of the proposed controller for a multi-phase machine is illustrated as well. Finally, experimental test results are demonstrated for a specific speed sensorless five phase induction motor test setup

  • FEM-based wave propagation modelling for SHM: Certain numerical issues in 1D structures
    • Magdalena Palacz
    • Arkadiusz Żak
    • Marek Krawczuk
    2020 Pełny tekst Materials

    The numerical modelling of structural elements is an important aspect of modern diagnostic systems. However, the process of numerical implementation requires advanced levels of consideration of multiple aspects. Important issues of that process are the positive and negative aspects of solution applied methods. Therefore the aim of this article is to familiarise the reader with the most important aspects related to the process of numerical modelling of one-dimensional problems related to the phenomena of the propagation of elastic waves and their application for damage detection purposes.

  • Filozofować z głębi człowieczeństwa. O fenomenologii Andrzeja Półtawskiego.
    • Andrzej Lisak
    2020 Kwartalnik Filozoficzny

    Dokonując krytyki tradycji nowożytnego empiryzmu i kartezjańskiego dualizmu Półtawski tworzy realistyczną i dynamiczną interpretację bytu ludzkiego. Przeżywanie, odczuwanie zmysłowe nie jest poślednią odmianą poznania jak i operacją dostarczania jedynie elementów, budulca poznaniu, ale odrębnym sposobem bycia w świecie, jest symbiotycznym kontaktem z otoczeniem, formą życia. Zrywa on radykalnie z tradycją brentanowsko-husserlowską traktowania świadomości jako zbioru aktów, a nie zbioru treści. Przeciwstawia temu model fenomenologii noematycznej. Nie możemy zobaczyć jak powstają noematy (treści świadomości), bo nie jest to robota samej świadomości, ani w sferze zmysłowego przeżywania, gdzie świat jest nam już pierwotnie dany jakby „od dołu” ani na wyższym poziomie świadomego funkcjonowania w świecie, gdzie świat (jako model świata), jest już nam znowuż dany, jakby „od góry”. Model świata tkwi nie w świadomości aktualnie obecnej, ale jakby za jej kulisami, aby umożliwić przytomne bycie człowieka w świecie. Ontologia wypracowana na gruncie najprostszego sposobu bycia człowieka jako tylko postrzegającego nie jest w stanie pojąć i zrozumieć realności świata, a zwłaszcza realności wartości. Oddać sprawiedliwość roli wartości może tylko całościowa i dynamiczna koncepcja człowieka, której wizji Półtawski szuka w konfrontacji z poglądami Ingardena , Strassera i Wojtyły.

  • Finiper
    • Luciano Segreto
    2020

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  • Finite Element Approaches to Model Electromechanical, Periodic Beams
    • Wiktor Waszkowiak
    • Marek Krawczuk
    • Magdalena Palacz
    2020 Pełny tekst Applied Sciences-Basel

    Periodic structures have some interesting properties, of which the most evident is the presence of band gaps in their frequency spectra. Nowadays, modern technology allows to design dedicated structures of specific features. From the literature arises that it is possible to construct active periodic structures of desired dynamic properties. It can be considered that this may extend the scope of application of such structures. Therefore, numerical research on a beam element built of periodically arranged elementary cells, with active piezoelectric elements, has been performed. The control of parameters of this structure enables one for active damping of vibrations in a specific band in the beam spectrum. For this analysis the authors propose numerical models based on the finite element method (FEM) and the spectral finite element methods defined in the frequency domain (FDSFEM) and the time domain (TDSFEM).

  • Finite element modelling of a historic church structure in the context of a masonry damage analysis
    • Marcin Kujawa
    • Izabela Lubowiecka
    • Czesław Szymczak
    2020 Pełny tekst ENGINEERING FAILURE ANALYSIS

    The paper includes a case study of modelling a real historic church using the finite element method (FEM) based on laser scans of its geometry. The main goal of the study was the analysis of the causes of cracking and crushing of masonry walls. An FEM model of the structure has been defined in ABAQUS. A non-linear dynamic explicit analysis with material model including damage plasticity has been performed. A homogenization procedure has been applied to obtain the material parameters used in the modelling of masonry. In the numerical analysis, the interactions between the church structure, the foundations and the ground were taken into account. The obtained results match well with the damaged area of the entire structure from the in-situ survey, and it should be highlighted that the proposed FEM model allows for a rather precise identification of the causes and effects of cracking walls in a qualitative sense. Also a brief research summary is presented.

  • Fish gelatin films containing aqueous extracts from phenolic-rich fruit pomace
    • Hanna Staroszczyk
    • Barbara Kusznierewicz
    • Edyta Malinowska-Pańczyk
    • Izabela Sinkiewicz
    • Karolina Gottfried
    • Ilona Kołodziejska
    2020 Pełny tekst LWT-FOOD SCIENCE AND TECHNOLOGY

    The aim of the work was to study the feasibility of using aqueous extracts from rowanberry, blue-berried honeysuckle, and chokeberry pomace for the formulation of fish gelatin films with antioxidant and antimicrobial activity as well as improved mechanical and water barrier properties. The predominant phenolic components in rowanberry and chokeberry extracts were hydroxycinnamates, and in blue-berried honeysuckle extract antho cyanins. Although the gelatin film itself showed antioxidative activity, addition of blue-berried honeysuckle extract increased it 3-fold. Unlike the films containing 1.2 mL of extract, the films with increased extract volume possessed strong antimicrobial properties against E. coli, P. fluorescens, S. aureus, L. innocua. Films plasticized with glycerol at 15 and 17.5% did not increase the mechanical strength in the presence of all extracts tested, but at 20%, a positive effect of each extract on mechanical strength was observed. None of the extracts affected the water barrier properties of the films.

  • Fixed Pattern Noise Reduction and Linearity Improvement in Time-Mode CMOS Image Sensors
    • Miron Kłosowski
    • Yichuang Sun
    2020 Pełny tekst SENSORS

    In the paper, a digital clock stopping technique for gain and offset correction in time-mode analog-to-digital converters (ADCs) has been proposed. The technique is dedicated to imagers with massively parallel image acquisition working in the time mode where compensation of dark signal non-uniformity (DSNU) as well as photo-response non-uniformity (PRNU) is critical. Fixed pattern noise (FPN) reduction has been experimentally validated using 128-pixel CMOS imager. The reduction of the PRNU to about 0.5 LSB has been achieved. Linearity improvement technique has also been proposed, which allows for integral nonlinearity (INL) reduction to about 0.5 LSB. Measurements confirm the proposed approach.

  • Flexoelectricity and apparent piezoelectricity of a pantographic micro-bar
    • Victor Eremeev
    • Jean-François Ganghoffer
    • Violetta Konopińska-Zmysłowska
    • Nikolay Uglov
    2020 Pełny tekst INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE

    We discuss a homogenized model of a pantographic bar considering flexoelectricity. A pantographic bar consists of relatively stiff small bars connected by small soft flexoelectric pivots. As a result, an elongation of the bar relates almost to the torsion of pivots. Taking into account their flexoelectric properties we find the corresponding electric polarization. As a results, the homogenized pantographic bar demonstrates piezoelectric properties inherited from the flexoelectric properties of pivots. The effective stiffness properties of the homogenized bars are determined by the geometry of the structural elements and shear stiffness whereas the piezoelectric properties follow from the flexoelectric moduli of the pivots.

  • Flexural behavior of composite structural insulated panels with magnesium oxide board facings
    • Łukasz Smakosz
    • Ireneusz Kreja
    • Zbigniew Pozorski
    2020 Pełny tekst Archives of Civil and Mechanical Engineering

    The current report is devoted to the flexural analysis of a composite structural insulated panel (CSIP) with magnesium oxide board facings and expanded polystyrene (EPS) core, that was recently introduced to the building industry. An advanced nonlinear FE model was created in the ABAQUS environment, able to simulate the CSIP’s flexural behavior in great detail. An original custom code procedure was developed, which allowed to include material bimodularity to significantly improve the accuracy of computational results and failure mode predictions. Material model parameters describing the nonlinear range were identified in a joint analysis of laboratory tests and their numerical simulations performed on CSIP beams of three different lengths subjected to three- and four-point bending. The model was validated by confronting computational results with experimental results for natural scale panels; a good correlation between the two results proved that the proposed model could effectively support the CSIP design process.

  • Flooding Extent Mapping for Synthetic Aperture Radar Time Series Using River Gauge Observations
    • Tomasz Berezowski
    • Tomasz Bieliński
    • Jakub Osowicki
    2020 Pełny tekst IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing

    The flooding extent area in a river valley is related to river gauge observations such as discharge and water elevations. The higher the water elevations, or discharge, the larger the flooding area. Flooding extent maps are often derived from synthetic aperture radar (SAR) images using thresholding methods. The thresholding methods vary in complexity and number of required parameters. We proposed a simple thresholding method that takes advantage of the correlation between the river gauge and the flooding area. To show the applicability of the method, we used a 2014–2018 time series of 161 Sentinel 1 SAR images acquired over a wetland floodplain located in Northeast Poland. We validated the method by extracting local water line elevations from a high-resolution digital elevation model for three river gauges, which resulted in a root-mean-square error of 0.16 m, a bias of 0.07 m, and a correlation of 0.86 for the best scenario. The scenario analysis showed that the most important factor affecting the method's accuracy was a proper delineation of the zone in which the flooding extent area was calculated. This was because other water sources, uncorrelated with river flow, were present in the floodplain as open water. Additionally, higher accuracy was obtained for the VV than VH polarization. The discharge can be used instead of water elevations as a river gauge variable, but this results in more bias in the water extent estimates.

  • Flow distribution and heat transfer in minigap and minichannel heat exchangers during flow boiling
    • Michał Klugmann
    • Paweł Dąbrowski
    • Dariusz Mikielewicz
    2020 Pełny tekst APPLIED THERMAL ENGINEERING

    The topic of boiling heat transfer in miniscale geometries has focused the ever increasing interest of researchers in recent years. However, most of the works are related to mini- and microchannels and much less to minigaps. Meanwhile, minigaps allow for more comprehensive experimental studies, i.e. flow visualisations due to the flat, two-dimensional configuration of the flow. The results of the experimental investigations of a model plate heat exchanger, composed of a single plate with a heat exchange surface of 0.1 m × 0.2 m, made of brass are presented. The working fluid is pure ethanol. Between the plate and the cover of the exchanger, 0.5 mm and 1.0 mm thick minigaps are arranged. The 0.5 mm minigap has been compared to an equivalent minichannel structure (a set of 50 parallel minichannels) with an equal cross-sectional area (rectangular 1 mm × 1 mm). An attempt to intensify the heat exchange by modifying the minigap wall was made. Two variants were tested to check the potential increase in the heat transfer coefficient and flow resistance. The section cover is transparent in order to simultaneously register the flow structures with the measurements. The heat is supplied using a water circuit, where the temperature and flow of the water can be regulated in a constant temperature water tank. The flow configuration of the exchanger is countercurrent, with the vertical flow of ethanol from the bottom to the top. The inlet and outlet manifolds are arranged as trapezoidal (Z-type design). The authors have analysed the efficiency of heat transport and pressure drop depending on the system operating parameters. The visualisations are thoroughly analysed to better understand the process. The main advantages of the presented work are a direct comparison of minigap and minichannel structures while standardising all other parameters; an interesting application of a simple, passive heat transfer intensification method which resulted in the unification of the velocity fields in the minigap and reduced maldistribution.

  • Fluctuation-Enhanced Sensing
    • Graziella Scandurra
    • Janusz Smulko
    • Laszlo B. Kish
    2020 Journal of Sensors

    Fluctuation-enhanced sensing (FES) is an exciting and relatively new research field that promises to extend the range of information that can be extracted from a single sensor. In FES, the stochastic fluctuations of the sensor signal, rather than its average value, are recorded and analyzed. Typical components of such fluctuations are due to interactions at the microscopic level. Proper statistical analysis provides optimum sensory information.

  • Fluctuation-Enhanced Sensing (FES): A Promising Sensing Technique
    • Graziella Scandurra
    • Janusz Smulko
    • Laszlo Kish
    2020 Pełny tekst Applied Sciences-Basel

    Fluctuation-enhanced sensing (FES) is a very powerful odor and gas sensing technique and as such it can play a fundamental role in the control of environments and, therefore, in the protection of health. For this reason, we conduct a comprehensive survey on the state-of-the-art of the FES technique, highlighting potentials and limits. Particular attention is paid to the dedicated instrumentation necessary for the application of the FES technique and also in this case limits and possible future developments are highlighted. In particular, we address resolution, measurement speed, reproducibility, memory, noise, and other problems such as the influence of humidity. A number of techniques and guidelines are proposed to overcome these problems. Circuit solutions are also discussed.

  • FLUID BED COATING OF MINITABLETS AND PELLETS WITH OPTIMIZATION OF THE PROCESS BASED ON TAGUCHI METHOD
    • Turk Magdalena
    • Bożenna Kawalec-Pietrenko
    • Małgorzata Sznitowska
    • Piotr Rybarczyk
    2020 Pełny tekst Acta Poloniae Pharmaceutica - Drug Research

    Small particles like pellets are coated in fluid bed systems. This method can be also feasible for minitablets but the selection of optimal process parameters is complicated. The aim of the research was to optimize the coating process for minitablets and to compare the conditions required for pellets. Minimum fluidization velocities (umf) for 2.0 and 2.5 mm minitablets and 0.7-0.8 mm or 1.0-1.25 mm pellets were determined experimentally. Additionally, the results were verified using the Ergun equation. The smallest relative differences between the calculated and experimental values of umf were obtained for P0.7 (4.6%), while the largest for MT2.5 (11.8%). To simplify optimization of the coating process, Design of Experiment (DoE) based on the Taguchi method was employed. Selection of the best process parameters was based on the film thickness measurements for minitablets, while the sieve analysis was used for pellets to detect agglomeration. The best combination of process parameters resulted in uniform film thickness in minitablets, with RSD less than 15%, and the pellets batch containing only 0.25% of bonded particles. It was found that the largest impact on the uniform film deposition on minitablets had a spraying pressure, responsible for the size of coating mixture droplets. In the case of pellets, the most critical was the inlet air temperature. The presented research demonstrated that it was possible to achieve the best parameters of the coating process for minitablets and pellets by combining calculations of minimum fluidization velocity and Design of Experiment based on the Taguchi method.

  • Forecasting risks and challenges of digital innovations
    • Marcin Sikorski
    2020

    Forecasting and assessment of societal risks related to digital innovation systems and services is an urgent problem, because these solutions usually contain artificial intelligence algorithms which learn using data from the environment and modify their behaviour much beyond human control. Digital innovation solutions are increasingly deployed in transport, business and administrative domains, and therefore, if abused by a malicious human activity or by a technical malfunction, may pose serious threats to public and to society. Contrary to enthusiastic promotional messages from business and industry circles, the public is increasingly concerned by numerous examples of abuse of DIs, including hacking of specific digital solutions, misuse of social media for destructive activities, or digital addiction spreading among young users. Although certainly not a new concept, the issue of designers’ responsibility for the social impact of their creations is becoming ever more actual, as a well as the search for preventive technological, cultural and institutional measures.This chapter presents early results of testing a new approach to forecasting and prioritizing societal risks associated with deploying digital innovations. This approach – termed the RADI methodology – features two new elements: combining small expert panels with AHP-processed human assessments, and a relationship matrix visually mapping identified threats with available preventive policies, including the Socially Responsible Design approach. Although in an early version, the RADI methodology has been shown to be useful in guiding expert panels in profiling arrays of interventions to be undertaken by specific institutions against potential damage caused by non-validated and non-certified digital innovations.

  • Formaldehyde detection with chemical gas sensors based on WO3 nanowires decorated with metal nanoparticles under dark conditions and UV light irradiation
    • Benachir Bouchikhi
    • Tomasz Chludziński
    • Tarik Saidi
    • Janusz Smulko
    • Nezha El Bari
    • He Wen
    • Radu Ionescu
    2020 Pełny tekst SENSORS AND ACTUATORS B-CHEMICAL

    We report results of formaldehyde gas (CH2O) detection under dark conditions and UV light irradiation with pristine tungsten trioxide nanowires (WO3 NWs) and metal nanoparticles decorated WO3 NWs gas sensing layers. The resistive layers were deposited by one step aerosol assisted chemical vapor deposition (AACVD) on commercial alumina substrates with 10-pair interdigitated platinum electrodes. The elaborated gas sensors, based on pristine WO3 and on WO3 decorated with Au, Pt, Au/Pt, Ni and Fe nanoparticles, were investigated towards three concentrations of formaldehyde gas (5, 10 and 15 ppm) under dark conditions and under UV light irradiation at the wavelength of 394 nm. Two main effects were observed: firstly, under UV light irradiation the response time for CH2O desorption was significantly reduced with the exception of the nanomaterial with Fe NPs dopant; secondly, the gas induced baseline shift was reduced under UV light irradiation conditions. These results can be explained by the additional energy induced by the UV light, accelerating the adsorption-desorption processes. The results obtained confirmed that both the decoration of WO3 NWs with selected metal nanoparticles as well as sensors operation under UV light irradiation are a practical and affordable way to enhance gas sensing towards formaldehyde detection, although both strategies applied together did not introduce an amplified synergetic effect.

  • Formation of a state institution on the basis of a process analysis - The concept of the institution of cadastre
    • Adam Klimek
    • Nogalski Bogdan
    • Agnieszka Szpitter
    • Joanna Czerska
    2020

    Modification of the structures of public administration encounters major obstacles. Institutional changes are difficult to introduce due to their complexity and broad impact. Non-substantial (political) factors are of importance as well. The resistance to change is aggravated by how difficult it is for decision-makers to assess the impact of the changes that are proposed. We present a method of handling such issues based on the process approach. It allows one to take a critical look at functioning state institutions and to develop draft changes. We discuss its application in the creation of concepts of institutional changes relying on the example of the administration segment, which handles geodesy and cartography in Poland. The study consists of three parts: the introduction, which defines the purpose of the work and presents the issues, method of conducting work, tools used, and the subject of research; the second part, in which the process of creating a cadastre concept is described based on the presented method; and the third part, namely the summary.

  • ─ Formation of a state institution on the basis of a process analysis - The concept of the institution of cadastre
    • Nogalski Bogdan
    • Adam Klimek
    • Joanna Czerska
    • Agnieszka Szpitte
    2020

    Modification of the structures of public administration encounters major obstacles. Institutional changes are difficult to introduce due to their complexity and broad impact. Non-substantial (political) factors are of importance as well. The resistance to change is aggravated by how difficult it is for decision-makers to assess the impact of the changes that are proposed. We present a method of handling such issues based on the process approach. It allows one to take a critical look at functioning state institutions and to develop draft changes. We discuss its application in the creation of concepts of institutional changes relying on the example of the administration segment, which handles geodesy and cartography in Poland. The study consists of three parts: the introduction, which defines the purpose of the work and presents the issues, method of conducting work, tools used, and the subject of research; the second part, in which the process of creating a cadastre concept is described based on the presented method; and the third part, namely the summary.

  • Formation of the hollow nanopillar arrays through the laser-induced transformation of TiO2 nanotubes
    • Jakub Wawrzyniak
    • Jakub Karczewski
    • Piotr Kupracz
    • Katarzyna Grochowska
    • Emerson Coy
    • Adam Mazikowski
    • Jacek Ryl
    • Siuzdak Katarzyna
    2020 Pełny tekst Scientific Reports

    In the following article, we present a simple, two-step method of creating spaced, hollow nanopillars, from the titania nanotube arrays via pulsed laser-treatment. Due to the high ordering of the structure, the prepared material exhibits photonic properties, which has been shown to increase the overall photoefficiency. The optical and morphological changes in the titania nanotubes after pulsed laser-treatment with 532, 355, and 266 nm wavelengths in the 10–50 mJ/cm2 fluence range are studied. The investigation reveals, that by using appropriate wavelength and energy, the number of surface defects, geometrical features, or both can be tailored.

  • Fotodachówka z systemem chłodzenia jako hybrydowy panel fotowoltaiczny – badania eksperymentalne
    • Jan Wajs
    • Aleksandra Gołąbek
    2020

    Panel fotowoltaiczny w formie dachówki, zbudowany z monokrystalicznych ogniw krzemowych, może tworzyć system solarny dla budownictwa, określany jako technologia Building-Integrated Photovoltaic (BIPV). Ze względu na spadek sprawności elektrycznej ogniw fotowoltaicznych wraz ze wzrostem temperatury pracy, poszukuje się metod ich skutecznego chłodzenia. Pozyskane w ten sposób ciepło można dodatkowo wykorzystać w innych procesach, np. dla potrzeb budownictwa mieszkaniowego lub budownictwa użyteczności publicznej. W artykule przedstawiono wyniki własnych badań z udziałem fotowoltaicznej dachówki chłodzonej powietrzem, stanowiącej hybrydowy panel fotowoltaiczny. Zaprezentowano stanowisko badawcze, wyposażone w symulator promieniowania słonecznego, oraz metodykę prowadzenia badań eksperymentalnych. Dokonano oceny wpływu warunków chłodzenia na temperaturę pracy dachówki oraz jej parametry elektryczne. W zakresie badań cieplnych, oszacowano gęstość pozyskanego strumienia ciepła, przy wydatkach objętościowych powietrza 1 i 4 m3/h, przepływającego w kanałach o wysokości 25 oraz 51 mm. Chłodzenie panelu fotowoltaicznego skutkowało maksymalnym wzrostem sprawności elektrycznej o 12,6%, a uzyskana całkowita sprawność konwersji promieniowania przekroczyła 32%.

  • fotografia pt. 'relacje nadzwyczajne'
    • Agnieszka Kurkowska
    2020

    Pandemia wymusiła relacje nadzwyczajne. Międzyludzkie i ludzko-przyrodnicze. Fotografia dokumentuje cykl instalacji artystycznych w przestrzeni lasu. Bohaterami dokumentowanych fotograficzne sytuacji są schematyczne zarysowane postaci ludzkie, w niecodziennej skali, niecodziennych ulokowaniach ale codziennych 'ułożeniach'. To czyni te relacje nadzwyczajnymi, choć pandemiczny kontekst społecznej izolacji ujmuje im semantyczny wydźwięk świąteczny. Utęskniona relacja z przyrodą paradoksalnie czyni te wykreowane spotkania wyjątkowymi.

  • FPGA Based Real Time Simulations of the Face Milling Process
    • Michał Mazur
    • Marek Galewski
    • Krzysztof Kaliński
    2020 Pełny tekst IEEE Access

    The article presents a successful implementation of the milling process simulation at the Field-Programmable Gate Array (FPGA). By using FPGA, very rigorous Real-Time (RT) simulation requirements can be met. The response time of the FPGA simulations is significantly reduced, and the time synchronization is better than in a typical RT system implemented in software. The FPGA-based approach is characterized by enormous flexibility when it comes to input and output operations that can be implemented deterministically in RT. Complex simulation software has been implemented using the High Level Synthesis technique, which is a relatively easy and fast approach for FPGA programming without using complex Hardware Description Languages. The hardware functions are based on procedures written in high-level C programming language. The mathematical descriptions of simulations, results of computer simulations, Hardware-in-the-Loop Simulation experiments, and real experiments are presented. The approach presented in this paper can be used to simulate the dynamics of various mechatronic systems.

  • FPGA-Based System for Electromagnetic Interference Evaluation in Random Modulated DC/DC Converters
    • Hermes Loschi
    • Piotr Lezynski
    • Robert Smolenski
    • Douglas Nascimento
    • Wojciech Śleszyński
    2020 Pełny tekst ENERGIES

    Field-Programmable Gate Array (FPGA) provides the possibility to design new “electromagnetic compatibility (EMC) friendly” control techniques for power electronic converters. Such control techniques use pseudo-random modulators (RanM) to control the converter switches. However, some issues connected with the FPGA-based design of RanM, such as matching the range of fixed-point numbers, might be challenging. The modern programming tools, such as LabVIEW, may facilitate the design process, but there are still fixed-point operations and limitations in arithmetic operations. This paper presents the design insights on the FPGA-based EMC friendly control system for DC/DC converter. Probability density functions (PDF) are used to analyse and improve pseudo-random algorithms. The theoretical algorithms, hardware details and experimental results are presented and discussed in terms of conducted electromagnetic interference emission.

  • Framework for Integration Decentralized and Untrusted Multi-vendor IoMT Environments
    • Andrzej Sobecki
    • Julian Szymański
    • David Gil
    • Higinio Mora
    2020 Pełny tekst IEEE Access

    Lack of standardization is highly visible while we use historical data sets or compare our model with others that use IoMT devices from different vendors. The problem also concerns the trust in highly decentralized and anonymous environments where sensitive data are transferred through the Internet and then are analyzed by third-party companies. In our research we propose a standard that has been implemented in the form of framework that allows describing requirements for methods and platforms that collect, manage, share, and perform data analysis form the Internet of Medical Things in order to increase trust. Further, we can distinguish two types of IoMT devices: passive and active. Passive devices measure some parameters of the body and save them in databases. Active devices have the functionality of passive devices and moreover, they can act in a defined way, eg.: inject directly into the patient's body some elements such as a medicament, electric signals to the nervous system, stimulus pacemaker, etc. Nevertheless how to create a safe and transparent environment for using data active sensors, developing safe ML models, performing medical decisions based on the created models and finally deploy this decision to the specified device. While the IoMT devices are used in real-life, professional healthcare the control system should offer tools for backtracking decisions, allowing e.g. to find who made a mistake, or which event caused a particular decision. Our framework provides backtracking in the IoMT environment in which for each medical decision supported by ML models we can prove which sensor sends the data, which data was used to create prediction/recommendation, what prediction was produced, who and when use it, what medical decision was made by who. We propose a vendor transparency framework for each IoMT devices and ML models that will process the medical data in order to increase patient's privacy and prevent for eventual data leaking.

  • Framework for Structural Health Monitoring of Steel Bridges by Computer Vision
    • Adam Marchewka
    • Patryk Ziółkowski
    • Victor Aguilar-vidal
    2020 Pełny tekst SENSORS

    The monitoring of a structural condition of steel bridges is an important issue. Good condition of infrastructure facilities ensures the safety and economic well-being of society. At the same time, due to the continuous development, rising wealth of the society and socio-economic integration of countries, the number of infrastructural objects is growing. Therefore, there is a need to introduce an easy-to-use and relatively low-cost method of bridge diagnostics. We can achieve these benefits by the use of Unmanned Aerial Vehicle-Based Remote Sensing and Digital Image Processing. In our study, we present a state-of-the-art framework for Structural Health Monitoring of steel bridges that involves literature review on steel bridges health monitoring, drone route planning, image acquisition, identification of visual markers that may indicate a poor condition of the structure and determining the scope of applicability. The presented framework of image processing procedure is suitable for diagnostics of steel truss riveted bridges. In our considerations, we used photographic documentation of the Fitzpatrick Bridge located in Tallassee, Alabama, USA.

  • Free Vibration of Flexomagnetic Nanostructured Tubes Based on Stress-driven Nonlocal Elasticity
    • Mohammad Malikan
    • Victor Eremeev
    2020 Pełny tekst

    A framework for the flexomagneticity influence is here considered extending the studies about this aspect on the small scale actuators. The developed model accommodates and composes linear Lagrangian strains, Euler-Bernoulli beam approach as well as an extended case of Hamilton’s principle. The nanostructured tube should subsume and incorporate size effect; however, for the sake of avoiding the staggering costs of experiments, here, via stress-driven nonlocal elasticity theory, the desired influence is captured. A given section is dedicated to reveal the accuracy of the achieved model. In view of solution, the numerical results are generated analytically. We receive the conclusion that in nanoscale tubes the diameter can affect fundamentally the performance of the flexomagnetic effect.

  • Frequency Diagnostics of Transformer Insulating Parameters
    • Peter Brnacal
    • Miroslav Gutten
    • Cefer Viktor
    • Daniel Korenciak
    • Leszek Jarzębowicz
    2020

    In the article is presented experimental analysis and diagnostics of insulating system oil-paper for power transformers, mainly by progressive frequency method – dielectric spectroscopy. In the 1-st part of the article is described base theory about measurement and diagnostics insulating part (oil and paper) of power transformers. In the 2-nd part of article is described measuring method of insulating frequency diagnostics - frequency domain spectroscopy (FDS). This method is used for analysis insulating condition of highvoltage equipment with insulating oil-paper. In the 3-st part of article is described measuring time method of insulating diagnostics - return voltage measurement (RVM). This method is used for analysis of condition of paper moisture of high-voltage equipment. The both measuring methods are unique in terms of analysis of insulating system of oil power transformers. In comparison with other methods, the RVM and FDS methods it is possible comparison and evaluate the moisture state of the dielectric paper of the power transformer with high reliability and accurate. Their reliability in determining moisture in paper was shown by determining the same result (3.5%) on the same measured distribution transformer.

  • Functional phase bistability in a nanocrystalline RbMn[Fe(CN)6] thin film fabricated by matrix-assisted laser evaporation
    • Dominik Maskowicz
    • Mirosław Sawczak
    • Rafał Jendrzejewski
    • Maria Gazda
    • Hiroko Tokoro
    • Shin-ichi Ohkoshi
    • Yann Garcia
    • Gerard Śliwiński
    2020 SCRIPTA MATERIALIA

    One of the main barriers hindering applications of Prussian blue metal assemblies is their poor processability, which makes the fabrication of intact thin films very difficult. In this work, a nanocrystalline RbMn[Fe(CN)6]·xH2O film on silicon substrate was obtained for the first time via laser-stimulated deposition and investigated. Temperature-induced phase transition and bistability within broad hysteresis loop (120 K), along with transition temperatures up to 317 K, which is the highest in the RbMnFe series, were observed using variable-temperature Raman spectroscopy. This study thus proposes a reliable deposition approach for preparing a functional magnetic materials that operate at room temperature.

  • Fundamental properties of solutions to fractional-order Maxwell's equations
    • Tomasz Stefański
    • Jacek Gulgowski
    2020 JOURNAL OF ELECTROMAGNETIC WAVES AND APPLICATIONS

    In this paper, fundamental properties of solutions to fractional-order (FO) Maxwell's equations are analysed. As a starting point, FO Maxwell's equations are introduced in both time and frequency domains. Then, we introduce and prove the fundamental properties of electromagnetic field in FO electromagnetics, i.e. energy conservation, uniqueness of solutions, and reciprocity. Furthermore, the algorithm of the plane wave simulation is developed and implemented in software, which allows us to demonstrate the general properties of electromagnetic field in the media described by FO models (FOMs). The differences in interpretation of the fundamental theorems of electromagnetics (i.e. Poynting's theorem, the uniqueness theorem and the Lorentz reciprocity theorem) in comparison to integer-order electromagnetics are analysed. It is demonstrated that all the properties of electromagnetic field, related to these fundamental theorems are preserved when time derivatives are generalized towards FO in Maxwell's equations.

  • Fundamental Schemes to Determine Disjoint Paths for Multiple Failure Scenarios
    • Teresa Gomes
    • Luisa Jorge
    • Rita Girão-Silva
    • Jose Yallouz
    • Péter Babarczi
    • Jacek Rak
    2020

    Disjoint path routing approaches can be used to cope with multiple failure scenarios. This can be achieved using a set of k (k> 2) link- (or node-) disjoint path pairs (in single-cost and multi-cost networks). Alternatively, if Shared Risk Link Groups (SRLGs) information is available, the calculation of an SRLG-disjoint path pair (or of a set of such paths) can protect a connection against the joint failure of the set of links in any single SRLG. Paths traversing disaster-prone regions should be disjoint, but in safe regions it may be acceptable for the paths to share links or even nodes for a quicker recovery. Auxiliary algorithms for obtaining the shortest path from a source to a destination are also presented in detail, followed by the illustrated description of Bhandari’s and Suurballe’s algorithms for obtaining a pair of paths of minimal total additive cost. These algorithms are instrumental for some of the presented schemes to determine disjoint paths for multiple failure scenarios.

  • Fundamentals of Communication Networks Resilience to Disasters and Massive Disruptions
    • Jacek Rak
    • David Hutchison
    • Janos Tapolcai
    • Rasa Bruzgiene
    • Massimo Tornatore
    • Carmen Mas-Machuca
    • Marija Furdek
    • Paul Smith
    2020

    Communication networks are exposed to a variety of massive failure events following from activities of nature, weather-induced disruptions, technology-implied problems, and malicious human activities. In this chapter, we first highlight the characteristics of these scenarios and discuss example failure events reported during the last three decades. Next, we explain the concept of network resilience and present an overview of major problems and related schemes further addressed in this monograph, concerning (a) measures and models for the analysis and evaluation of disaster-resilient networks, (b) techniques for design and update of disaster-resilient systems, (c) algorithms and schemes for resilient systems, and (d) advanced topics focusing, e.g. on emerging communication technologies.

  • Fuzzy Control of Waves Generation in a Towing Tank
    • Marcin Drzewiecki
    • Jarosław Guziński
    2020 Pełny tekst ENERGIES

    This paper presents the results of research related to the transformation of electrical energy into potential and kinetic energy of waves generated on the water surface. The waves are generated to model the environmental conditions for the needs of the model tests. The model tests are performed on model-scale objects to predict the features of full-scale maritime objects. It is done to improve human safety and the survivability of constructions. Electrical energy is transformed into the energy of the water waves using a wave maker. The wave maker considered is a facility with an electrohydraulic drive and an actuator submerged into the water. The actuator movement results in the waves being mechanically-generated in accordance with the wave maker theory. The study aimed to investigate the advantage of the newly implemented fuzzy-logic controller over the hitherto cascading proportional-integral controllers of the wave maker actuator. The research was focused on experimental investigation of the transformation process outcomes harvested under the fuzzy-logic controller, versus the cascading proportional-integral controllers. The waves were generated and measured in the real towing tank, located in the Maritime Advanced Research Centre (CTO S.A.). The investigation confirmed the advantage of the fuzzy-logic controller. It provides more accurate transformation of energy into the desired form of the water waves of specified parameters—frequency and amplitude—and more flat amplitude-frequency characteristic of the transformation process.

  • Fuzzy Divisive Hierarchical Clustering of Solvents According to Their Experimentally and Theoretically Predicted Descriptors
    • Miroslava Nedyalkova
    • Costel Sarbu
    • Marek Tobiszewski
    • Vasil Simeonov
    2020 Pełny tekst Symmetry-Basel

    The present study describes a simple procedure to separate into patterns of similarity a large group of solvents, 259 in total, presented by 15 specific descriptors (experimentally found and theoretically predicted physicochemical parameters). Solvent data is usually characterized by its high variability, dierent molecular symmetry, and spatial orientation. Methods of chemometrics can usefully be used to extract and explore accurately the information contained in such data. In this order, advanced fuzzy divisive hierarchical-clustering methods were eciently applied in the present study of a large group of solvents using specific descriptors. The fuzzy divisive hierarchical associative-clustering algorithm provides not only a fuzzy partition of the solvents investigated, but also a fuzzy partition of descriptors considered. In this way, it is possible to identify the most specific descriptors (in terms of higher, smallest, or intermediate values) to each fuzzy partition (group) of solvents. Additionally, the partitioning performed could be interpreted with respect to the molecular symmetry. The chemometric approach used for this goal is fuzzy c-means method being a semi-supervised clustering procedure. The advantage of such a clustering process is the opportunity to achieve separation of the solvents into similarity patterns with a certain degree of membership of each solvent to a certain pattern, as well as to consider possible membership of the same object (solvent) in another cluster. Partitioning based on a hybrid approach of the theoretical molecular descriptors and experimentally obtained ones permits a more straightforward separation into groups of similarity and acceptable interpretation. It was shown that an important link between objects’ groups of similarity and similarity groups of variables is achieved. Ten classes of solvents are interpreted depending on their specific descriptors, as one of the classes includes a single object and could be interpreted as an outlier. Setting the results of this research into broader perspective, it has been shown that the fuzzy clustering approach provides a useful tool for partitioning by the variables related to the main physicochemical properties of the solvents. It gets possible to oer a simple guide for solvents recognition based on theoretically calculated or experimentally found descriptors related to the physicochemical properties of the solvents.

  • Fuzzy Multi-Regional Fractional PID controller for Pressurized Water nuclear Reactor
    • Bartosz Puchalski
    • Tomasz Rutkowski
    • Kazimierz Duzinkiewicz
    2020 Pełny tekst ISA TRANSACTIONS

    The paper presents the methodology for the synthesis of a Fuzzy Multi-Regional Fractional Order PID controller (FMR-FOPID) used to control the average thermal power of a PWR nuclear reactor in the load following mode. The controller utilizes a set of FOPID controllers and the fuzzy logic Takagi-Sugeno reasoning system. The proposed methodology is based on two optimization parts. The first part is devoted to finding the optimal parameters of local FOPID controllers and in the second part, the optimal membership functions of the fuzzy reasoning system are designed. During the controller designing and comparison phase, the two validated nodal models of a nuclear reactor are used, simplified model and extended model respectively. The proposed approach has been verified by computer simulations that confirm its effectiveness.

  • GaN Nanowire Array for Charge Transfer in Hybrid GaN/P3HT:PC71BM Photovoltaic Heterostructure Fabricated on Silicon
    • Giorgi Tchutchulashvili
    • Sergij Chusnutdinow
    • Wojciech Mech
    • Krzysztof P. Korona
    • Anna Reszka
    • Marta Sobanska
    • Zbigniew R. Zytkiewicz
    • Wojciech Sadowski
    2020 Pełny tekst Materials

    Abstract: We demonstrate that a GaN nanowire array can be used for efficient charge transfer between the organic photovoltaic layer and silicon in a Si/GaN/P3HT:PC71BM inverted hybrid heterostructure. The band alignment of such a material combination is favorable to facilitate exciton dissociation, carrier separation and electron transport into Si. The ordered nature of the GaN array helps to mitigate the intrinsic performance limitations of the organic active layer. The dependence of photovoltaic performance enhancement on the morphology of the nanostructure with nanowire diameters 30, 50, 60, 100 and 150 nm was studied in detail. The short circuit current was enhanced by a factor of 4.25, while an open circuit voltage increase by 0.32 volts was achieved compared to similar planar layers.

  • Gdańsk 2020
    • Krzysztof Wróblewski
    2020

    Na wystawie Gdańsk 2020 prezentujemy prace, które były odpowiedzią na sytuację, w jakiej znaleźli się artyści w obliczu zamrożenia działań kulturalnych, które są oddaniem emocji pierwszych tygodni izolacji. To komentarz do konkretnego czasu, ale też do sytuacji artystów i kryzysu, który przed nami, a także do sytuacji twórców w Polsce w ogóle – mówi Aleksandra Szymańska, dyrektorka Instytutu Kultury Miejskiej. Otwarcie wystawy online, która prezentuje 50 prac gdańskich artystów i artystek odbędzie się 3 czerwca o godz. 19.00 na Facebooku IKM-u oraz na portalu gdansk.pl. Prace będą dostępne na stronie www.gdansk2020.eu. Wernisaż wystawy odbędzie się online 3 czerwca o godz. 19.00 na Facebooku IKM-u: https://www.facebook.com/IKMgdansk/ oraz na www.gdansk.pl.

  • Gdańsk: a City of Solidarity and Freedom
    • Piotr Lorens
    • Izabela Mironowicz
    2020 disP

    Only a few cities can claim that they have changed Europe and indeed the World. Gdańsk is privileged to be one of them. It is not a “caprice of history” that the Solidarity movement which, in the end, got the iron curtain torn, was born in this particular place. It is a logical consequence of ten centuries of the collective wisdom of the people that built Gdańsk and the region of Pomerania. The tragic assassination of the Mayor of Gdańsk, Paweł Adamowicz, in 2019, reminds us that these values that city represents – solidarity and freedom – should be recaptured from those who want to push our cities towards other principles. Gdańsk is once again becoming a symbol of the choice we all have to face. Is the city ready to set sail towards a new destination in its stormy history?

  • Gdyński modernizm lat międzywojennych. Oblicze stylowe epoki = Modernism of the Interwar Period of Gdynia. A Picture of the Style of the Epoch
    • Maria Sołtysik
    2020

    Lata dwudzieste i trzydzieste XX wieku, a więc czas w którym Gdynia powstawała, nie są w historii architektury okresem homogenicznym. Stylistyka modernizmu lat międzywojennych - wbrew swym uniwersalistycznym założeniom ideowym - nosiła w sobie dużą różnorodność. Widzimy to zarówno w odniesieniu do Gdyni, jak i w ogóle do architektury europejskiej tego okresu. Niniejszy rozdział prezentuje cztery główne oblicza architektury modernistycznej Gdyni: wczesno modernistyczny nurt Art Déco, skrajnie awangardowy nurt funkcjonalizmu, luksusowy nurt streamline moderne oraz umiarkowanie modernistyczny nurt wertykalizmu.

  • Gender-Related Differences in Trimethylamine and Oxidative Blood Biomarkers in Cardiovascular Disease Patients
    • Laura Bordoni
    • Donatella Fedeli
    • Marco Piangerelli
    • Iwona Pelikant-Malecka
    • Adrianna Radulska
    • Joanna J. Samulak
    • Angelika K. Sawicka
    • Lukasz Lewicki
    • Leszek Kalinowski
    • Robert A. Olek
    • Rosita Gabbianelli
    2020 Pełny tekst Biomedicines

    Gender differences in the burden of cardiovascular disease (CVD) have been observed worldwide. In this study, plasmatic levels of trimethylamine (TMA) and blood oxidative biomarkers have been evaluated in 358 men (89 controls and 269 CVD patients) and 189 women (64 control and 125 CVD patients). The fluorescence technique was applied to determine erythrocyte membrane fluidity using 1,6-diphenyl-1,3,5-hexatriene (DPH) and Laurdan, while lipid hydroperoxides were assessed by diphenyl − 1-pyrenylphosphine (DPPP). Results show that levels of plasmatic TMA were higher in healthy men with respect to healthy women (p = 0.0001). Significantly lower TMA was observed in male CVD patients (0.609 ± 0.104 μM) compared to healthy male controls (0.680 ± 0.118 μ M) ( p < 0.001), while higher levels of TMA were measured in female CVD patients (0.595 ± 0.115 μ M) with respect to female controls (0.529 ± .073 μ M) ( p < 0.001). DPPP was significantly higher in healthy control men than in women (p < 0.001). Male CVD patients displayed a lower value of DPPP (2777 ± 1924) compared to healthy controls (5528 ± 2222) ( p < 0.001), while no significant changes were measured in females with or without CVD (p > 0.05). Membrane fluidity was significantly higher ( p < 0.001) in the hydrophobic bilayer only in control male subjects. In conclusion, gender differences were observed in blood oxidative biomarkers, and DPPP value might be suggested as a biomarker predictive of CVD only in men.

  • Generalized Gradient Equivariant Multivalued Maps, Approximation and Degree
    • Zdzisław Dzedzej
    • Tomasz Gzella
    2020 Pełny tekst Mathematics

    Consider the Euclidean space Rn with the orthogonal action of a compact Lie group G. We prove that a locally Lipschitz G-invariant mapping f from Rn to R can be uniformly approximated by G-invariant smooth mappings g in such a way that the gradient of g is a graph approximation of Clarke’s generalized gradient of f . This result enables a proper development of equivariant gradient degree theory for a class of set-valued gradient mappings

  • Generation and Characterization of a DNA-GCN4 Oligonucleotide-Peptide Conjugate: The Impact DNA/Protein Interactions on the Sensitization of DNA
    • Paweł Wityk
    • Rafał Piątek
    • Dorota Kostrzewa-Nowak
    • Robert Nowak
    2020 Pełny tekst MOLECULES

    Radiotherapy, the most common therapy for the treatment of solid tumors, exerts its effects by inducing DNA damage. To fully understand the extent and nature of this damage, DNA models that mimic the in vivo situation should be utilized. In a cellular context, genomic DNA constantly interacts with proteins and these interactions could influence both the primary radical processes (triggered by ionizing radiation) and secondary reactions, ultimately leading to DNA damage. However, this is seldom addressed in the literature. In this work, we propose a general approach to tackle these shortcomings. We synthesized a protein-DNA complex that more closely represents DNA in the physiological environment than oligonucleotides solution itself, while being sufficiently simple to permit further chemical analyses. Using click chemistry, we obtained an oligonucleotide-peptide conjugate, which, if annealed with the complementary oligonucleotide strand, forms a complex that mimics the specific interactions between the GCN4 protein and DNA. The covalent bond connecting the oligonucleotide and peptide constitutes a part of substituted triazole, which forms due to the click reaction between the short peptide corresponding to the specific amino acid sequence of GCN4 protein (yeast transcription factor) and a DNA fragment that is recognized by the protein. DNAse footprinting demonstrated that the part of the DNA fragment that specifically interacts with the peptide in the complex is protected from DNAse activity. Moreover, the thermodynamic characteristics obtained using differential scanning calorimetry (DSC) are consistent with the interaction energies calculated at the level of metadynamics. Thus, we present an efficient approach to generate a well-defined DNA-peptide conjugate that mimics a real DNA-peptide complex. These complexes can be used to investigate DNA damage under conditions very similar to those present in the cell.

  • Generic invariant measures for iterated systems of interval homeomorphisms
    • Wojciech Czernous
    • Tomasz Szarek
    2020 Pełny tekst ARCHIV DER MATHEMATIK

    It is well known that iterated function systems generated by orientation preserving homeomorphisms of the unit interval with positive Lyapunov exponents at its ends admit a unique invariant measure on (0, 1) provided their action is minimal. With the additional requirement of continuous differentiability of maps on a fixed neighbourhood of {0,1} { 0 , 1 } , we present a metric in the space of such systems which renders it complete. Using then a classical argument (and an alternative uniqueness proof), we show that almost singular invariant measures are admitted by systems lying densely in the space. This allows us to construct a residual set of systems with unique singular stationary distribution. Dichotomy between singular and absolutely continuous unique measures is assured by taking a subspace of systems with absolutely continuous maps; the closure of this subspace is where the residual set is found.

  • Genetic Algorithm Approach for Gains Selection of Induction Machine Extended Speed Observer
    • Daniel Wachowiak
    2020 Pełny tekst ENERGIES

    The subject of this paper is gains selection of an extended induction machine speed observer. A high number of gains makes manual gains selection difficult and due to nonlinear equations of the observer, well-known methods of gains selection for linear systems cannot be applied. A method based on genetic algorithms has been proposed instead. Such an approach requires multiple fitness function calls; therefore, using a quality index based on simulations makes gains selection a time-consuming process. To find a fitness function that evaluates, in a short time, quality indices based on poles placement have been proposed. As the observer is nonlinear, equations describing the observer dynamics have been linearized. The relationship between poles placement and real dynamic properties has been shown. A series of studies has been performed to investigate the influence of the operating point of the machine on the dynamics of the observer. It has been proven that rotor speed has a significant impact on the placement of the poles and the observer may lose stability after a rotation direction change. A method of gains modification to maintain symmetrical properties of the observer for both directions has been presented. Experimental studies of the observer during machine reverse in the open and closed-loop control system have been performed. The results show that the observer can be implemented in a sensorless drive, using the proposed gains selection method.

  • Genetic and Epigenetic Aspects of Atopic Dermatitis
    • Bogusław Nedoszytko
    • Edyta Reszka
    • Danuta Gutowska-Owsiak
    • Magdalena Trzeciak
    • Magdalena Lange
    • Justyna Jarczak
    • Marek Niedoszytko
    • Ewa Jablonska
    • Jan Romantowski
    • Dominik Strapagiel
    • Jarosław Skokowski
    • Anna Siekierzycka
    • Roman J. Nowicki
    • Iwona T. Dobrucki
    • Anna Zaryczańska
    • Leszek Kalinowski
    2020 Pełny tekst INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES

    Atopic dermatitis is a heterogeneous disease, in which the pathogenesis is associated with mutations in genes encoding epidermal structural proteins, barrier enzymes, and their inhibitors; the role of genes regulating innate and adaptive immune responses and environmental factors inducing the disease is also noted. Recent studies point to the key role of epigenetic changes in the development of the disease. Epigenetic modifications are mainly mediated by DNA methylation, histone acetylation, and the action of specific non-coding RNAs. It has been documented that the profile of epigenetic changes in patients with atopic dermatitis (AD) di ff ers from that observed in healthy people. This applies to the genes a ff ecting the regulation of immune response and inflammatory processes, e.g., both a ff ecting Th1 bias and promoting Th2 responses and the genes of innate immunity, as well as those encoding the structural proteins of the epidermis. Understanding of the epigenetic alterations is therefore pivotal to both create new molecular classifications of atopic dermatitis and to enable the development of personalized treatment strategies.