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Search results for: TIME-DEPENDENT
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Security Evaluation of IT Systems Underlying Critical Networked Infrastructures
PublicationCritical infrastructures have become highly dependent on information and communication technology (ICT). The drawback of this situation is that the consequences of disturbances of the underlying ICT networks may be serious as cascading effects can occur. This raises a high demand for security assurance, with a high importance assigned to security evaluations. In this paper we present an experiment-centric approach for the characterisation...
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Correlated Particle Motion and THz Spectral Response of Supercritical Water
PublicationMolecular dynamics simulations of supercritical water reveal distinctly different distance-dependent modulations of dipolar response and correlations in particle motion compared to ambient conditions. The strongly perturbed H-bond network of water at supercritical conditions allows for considerable translationaland rotational freedom of individual molecules. These changes give rise to substantially different infrared spectra and...
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Security ontology construction and integration
PublicationThere are many different levels on which we can examine security. Each one is different from others, all of them are dependent on the context. Hence the need to bear additional knowledge enabling efficient utilization of the knowledge by the computers. Such information can be provided by ontologies. The paper presentsgathered requirements needed to be taken into account when creating an ontology. The method of ontology creation...
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Enhancing nitrogen removal in the partial denitrification/anammox processes for SO4− - Rich wastewater treatment: Insights into autotrophic and mixotrophic strategies
PublicationThe investigation of partial denitrification/anammox (PD/anammox) processes was conducted under autotrophic (N–S cycle) and mixotrophic (N–S–C cycle) conditions over 180 days. Key findings revealed the remarkable capability of SO42--dependent systems to produce NO2− effectively, supporting anaerobic NH4+ oxidation. Additionally, SO42− served as an additional electron acceptor in sulfate reduction ammonium oxidation (SRAO). Increasing...
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The influence of Nigella sativa essential oil on proliferation, activation, and apoptosis of human T lymphocytes in vitro
PublicationIn previous work, we tested the immunomodulatory effect of Nigella sativa (NS) fatty oil. Our results demonstrated that unrefined, obtained by cold pressing black cumin seed oil inhibited lymphocytes’ proliferation and induced their apoptosis in a dose-dependent manner. In this study, we examined the immunomodulatory properties of essential oil (EO) obtained from the NS seeds by hydrodistillation and its two main constituents:...
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Dissection of σE‐dependent cell lysis in Escherichia coli: roles of RpoE regulators RseA, RseB and periplasmic folding catalyst PpiD
PublicationTo understand the mechanism of sigma(E)-dependent cell lysis, we examined the consequences of deletion derivatives of rpoE regulators rseA, rseB and rseC on sigma(E) transcription, on levels of free versus membrane-bound sigma(E) and on OMP-biogenesis limiting factor(s) that could impact cell lysis. RT-PCR showed that individual nonpolar DeltarseA and DeltarseB increased the rpoE expression to varying extents, with pronounced induction...
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Superconductivity in the Nb-Ru-Ge σ phase
PublicationWe show that the previously unreported ternary σ-phase material Nb20.4Ru5.7Ge3.9 (Nb0.68Ru0.19Ge0.13) is a superconductor with a critical temperature of 2.2 K. Temperature-dependent magnetic susceptibility, resistance, and specific-heat measurements were used to characterize the superconducting transition. The Sommerfeld constant γ for Nb20.4Ru5.7Ge3.9 is 91 mJ mol f.u. −1K−2 (∼3 mJ mol atom−1 K−2) and the specific-heat anomaly at...
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Selected problems of experimental investigation of dynamically loaded journal bearings
PublicationIn the paper some problems concerning relations between external bearing loadings and critical lining stresses are described for test stand with rotating load vector. According to the standard ISO 7905/1 this type of test stand, for dynamically loaded slide bearing, is recommended as a basic research unit for material testing in a complete bearing unit. The lining stress calculation results occurred being dependent on applied calculation...
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New clicked full agonists of the estrogen receptor β
PublicationA click chemistry approach was used to synthesize a series of 1,4-diaryl-substituted 1,2,3-triazoles designed to behave as estrogen receptor (ER) ligands. We studied their affinities for both receptors α and β, their agonist activities in a cell-based luciferase reporter assay and their effect on the proliferation of the hormone-dependent MCF-7 cell line. We found two compounds (3a and 3c) that behave as selective full agonists...
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Interferometric Sensor of Wavelength Detuning Using a Liquid Crystalline Polymer Waveplate
PublicationOperation of a polarization interferometer for measurement of the wavelength changes of a tunable semiconductor laser was investigated. A lambda/8 waveplate made from liquid crystalline polymer is placed in one of interferometers’ arms in order to generate two output signals in quadrature. Wavelength was measured with resolution of 2 pm in the wavelength range 628–635 nm. Drift of the interferometer, measured in the period of 500...
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The homometallic warwickite V 2 OBO 3
PublicationThe synthesis, structure and elementary magnetic characterization of the homometallic warwickite V2OBO3 are reported. The material adopts the orthorhombic warwickite structure type at room temperature, space group Pnma (No. 62) with lattice parameters a = 9.2317(1) Å, b = 3.1172(1) Å, and c = 9.5313(1) Å. Temperature-dependent magnetic susceptibility, electrical resistivity, and specific heat measurements show anomalies near 35 K,...
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Thermodynamics and Intermolecular Interactions of Nicotinamide in Neat and Binary Solutions: Experimental Measurements and COSMO-RS Concentration Dependent Reactions Investigations
PublicationIn this study, the temperature-dependent solubility of nicotinamide (niacin) was measured in six neat solvents and five aqueous-organic binary mixtures (methanol, 1,4-dioxane, acetonitrile, DMSO and DMF). It was discovered that the selected set of organic solvents offer all sorts of solvent effects, including co-solvent, synergistic, and anti-solvent features, enabling flexible tuning of niacin solubility. In addition, differential...
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Rheology of potato starch chemically modified with microwave-assisted reactions
PublicationNative potato starch was sulfated, selenated, borated, silicated and zincatated by means of microwave-assisted reactions with varying doses of relevant reagents. Resulting products were characterized involving rheological behavior of pastes, their weight-average molecular weight (Mw), and radius of gyration (Rg). Most of the pastes showed shear-thinning behavior, with the flow behavior index (n) below unity. The pastes of starch...
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In vitro enzyme kinetics and NMR-based product elucidation for glutathione S-conjugation of the anticancer unsymmetrical bisacridine C-2028 in liver microsomes and cytosol: major role of glutathione S-transferase M1-1 isoenzyme
PublicationThis work is the next step in studying the interplay between C-2028 (anticancer-active unsymmetrical bisacridine developed in our group) and the glutathione S-transferase/glutathione (GST/GSH) system. Here, we analyzed the concentration- and pH-dependent GSH conjugation of C-2028 in rat liver microsomes and cytosol. We also applied three recombinant human GST isoenzymes, which altered expression was found in various tumors. The...
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Adipokine and cytokine levels in non-functioning adrenal incidentalomas (NFAI)
PublicationDue to the fact that overweight or obesity is accompanied by hormonally active adrenal tumors: Cushing Syndrome-(CS) and Subclinical Cushing Syndrome (SCS), it is of high interest the correlation between different adipokines and cytokines secreted by adipose tissue, with metabolic disorders and hormonal activity in this group. Even in non-functioning adrenal incidentalomas (NFAI) elevated risk for cardiovascular disease and metabolic...
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Characterization of d-xylose reductase, XyrB, from Aspergillus niger
PublicationD-xylose reductase is a member of the aldo-keto reductase family, and is involved in D-xylose and L-arabinose conversion through the Pentose Catabolic Pathway (PCP) in fungi. In this study, we biochemically characterized a newly identified second D-xylose reductase (XyrB) from Aspergillus niger. This NADPH-dependent reductase is able to efficiently convert D-xylose and L-arabinose, and it has the highest affinity for these sugars...
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Polarization interferometer using a Liquid Crystalline Polymer waveplate for wavelength measurement
PublicationA two-beam polarization interferometer for measuring wavelength changes of a tunable semiconductor laser was designed, built and tested. This interferometer uses a λ/8 waveplate made from Liquid Crystalline Polymer in order to generate two output signals in quadrature. The λ/8 waveplate can be manufactured either on a beamsplitter face or on the mirror surface, reducing the cost and complexity of the optomechnical assembly. Experiment...
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Electrochemical oxidation of sulphamerazine at boron-doped diamond electrodes: Influence of boron concentration
PublicationThe boron-doped diamond (BDD) electrodes with different boron concentrations have been tested as electrode material for sulphamerazine (SRM) oxidation in water solution. An investigation of the electrode morphology and molecular structure was carried out using high resolution scanning electron microscopy (SEM) and Raman spectroscopy. Electrochemical results showed clearly that the kinetics and efficiency of SRM oxidation were dependent...
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A Trisection Filter Design With Negative Slope of Frequency-Dependent Crosscoupling Implemented in Substrate Integrated Waveguide (SIW)
PublicationThis letter reports on a novel realization of a microwave bandpass filter in a triplet configuration with a frequency-dependent crosscoupling implemented in substrate integrated waveguide (SIW). The design involves implementing dispersive coupling with a negative slope, a feature that allows the capabilities of the classic triplet topology to be extended. In this particular case, the implementation of two transmission zeros on...
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Coupled-Resonator Waveguide Filter in Quadruplet Topology With Frequency-Dependent Coupling - A Design Based on Coupling Matrix
PublicationThis letter presents an application of a recently developed coupling matrix synthesis technique to design of coupled-resonator filters with dispersive inter-resonator couplings. This technique is used to design a novel coupled-cavity bandpass filter. Measurements validate the design and confirm effectiveness of the synthesis method. The filter is a four-pole generalized Chebyshev filter with three transmission zeros. Resonators...
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The Determinants of False Self-Employment: A Survey of Polish Enterprises
PublicationThe main goal of this article is to advance the emergent research on tax evasion in Poland in the form of false self-employment (FSE), in particular to identify its causes. The dependent character of some self-employed workers is a big problem in the Polish economy, which has been completely unexplored because of the lack of available data. In this article, we use data from a survey of Polish companies. Our empirical results show...
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Modified SPWM Technique with Zero-Sequence Voltage Injection for a Five-Phase, Three-Level NPC Inverter
PublicationThis article presents a modified sinusoidal pulse-width modulation (SPWM) scheme for a five-phase, three-level neutral-point-clamped inverter. The modulation scheme deploys a modified min–max function to inject the zero-sequence components into the reference modulating signals; hence enabling the effective utilization of the DC-link voltage. Balanced split-input DC-link voltages were achieved through further incorporation of adjustable...
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Tunable Dielectric Switching of (Quinuclidinium)[MnCl4] Hybrid Compounds
PublicationInorganic−organic hybrid QMnCl (Q = quinuclidinium) crystals were synthesized and characterized. The X-ray and variable-temperature IR/Raman analysis demonstrate that the crystals undergo a reversible structural phase transition, which originates from an order−disorder process and is related to the dynamics of the organic Q cation. Dielectric function measurements disclose a switchability between low (“OFF”) and high (“ON”) dielectric...
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Badanie rozkładów parametrów sygnału mowy w zastosowaniach do prognozowania prawdopodobieństwa popełnienia błędów w systemach identyfikacji mówców = Examining distribution of speech signal parameters for the prognosis of error probability in speaker verification systems
PublicationPrzedmiotem pracy jest system identyfikacji mówców w sposób zależny od tekstu ("text dependent''). Dokonano analizy wielu różnych wypowiedzi kilkudziesięciu mówców. Zastosowana metoda parametryzacji to metoda oparta na wynikach analizy cepstralnej sygnału mowy. Zdefiniowane zostały nowe parametry skojarzone z elementarnymi zdarzeniami w procesie weryfikacji mówców. Na tej podstawie dokonano estymacji funkcji gęstości prawdopodobieństwa...
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Annihilation rates of low-energy positron scattering from simple diatomic molecules
PublicationWe discuss the calculations of Zeff coefficients for a series of diatomic molecules over the range of energies below the positronium formation. During the development of a general code for polyatomic, nonlinear molecules colliding with positrons, it was discovered that the earlier one, employed only for diatomic molecules, had an error. The error is corrected and the corrected results are presented here. We also discuss a way of...
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Situational Awareness Network for the Electric Power System: the Architecture and Testing Metrics
PublicationThe contemporary electric power system is highly dependent on Information and Communication Technologies which results in its exposure to new types of threats, such as Advanced Persistent Threats (APT) or Distributed-Denial-of-Service (DDoS) attacks. The most exposed components are Industrial Control Systems in substations and Distributed Control Systems in power plants. Therefore, it is necessary to ensure the cyber security of...
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TS-based RSM-aided design of cold-formed steel stiffened C-sectional columns susceptible to buckling
PublicationThe paper focuses on joint-performance analysis of a built-up cold-formed thin-walled C-sectional column with a fillister (stiffener) of the same type, interconnected with a series of bolts located along the length of the compressed members in specific spacing. The quantity of bolts and the non-connected starting distance of the fillister are considered random variables of the problem. Optimal distribution of joints on the stiffener...
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The field–dependent interface recombination velocity for organic–inorganic heterojunction
PublicationWe have derived an analytical formula which describes the field–dependent interface recombination velocity for the boundary of two materials characterized by different permittivities. The interface recombination of charge carriers has been considered in the presence of image force Schottky barrier. We suggest that this effect may play an important role in the loss of current for organic–inorganic hybrid heterojunctions. It has...
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The impact of training and neurotrophins on functional recovery after spinal cord transection: cellular and molecular mechanisms contributing to motor improvement
PublicationBeneficial effects of locomotor training on the functional recovery after complete transection of the spinal cord indicate that in chronic spinal animals spontaneous recovery processes are enhanced and shaped by the training. The mechanisms of that use-dependent improvement are still not fully understood. This review tackles three aspects of this issue: (1) neurochemical attributes of functional improvement...
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City scan as a tool to assess resilience challenges and vulnerabilities at the community level
PublicationThe majority of the world’s population lives in cities and cities are the key to achieving resilience. Local governments own only part of the land and can only partially decide about measures that should be taken ‘on the ground’. Local governments are therefore highly dependent on individuals, communities, and businesses to adapt and transform and take action in their own backyards or neighbourhoods. Since, for many people, climate...
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Evolution of charge density wave order in continuous solid solutions Lu(Ni1-xCox)C2
PublicationPseudo-ternary solid solutions, Lu(Ni1-xCox)C2 (0 ≤ x ≤ 1), were studied by means of powder X-ray diffraction, differential thermal analysis as well as electrical resistivity and heat capacity measurements. The crystal structure of the Lu(Ni1-xCox)C2 series, as investigated by means of X-ray powder diffraction, is of structure type CeNiC2, space group Amm2, Pearson symbol oS8. The structural analysis reveals a non-monotonous evolution,...
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Two bacterial small heat shock proteins, IbpA and IbpB, form a functional heterodimer
PublicationSmall heat shock proteins (sHsps) are a conserved class of ATP-independent chaperones which in stress conditions bind to unfolded protein substrates and prevent their irreversible aggregation. Substrates trapped in sHsps-containing aggregates are efficiently refolded into native structures by ATP-dependent Hsp70 and Hsp100 chaperones. Most γ-proteobacteria possess a single sHsp (IbpA), while in a subset of Enterobacterales, as...
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Fluctuation enhanced gas sensing with WO3-based nanoparticle gas sensors modulated by UV light at selected wavelengths
PublicationThe sensitivity and selectivity of WO3-based gas sensors can be enhanced by UV-irradiation-induced modulation, especially if different wavelengths are employed. We used fluctuation-enhanced gas sensing, based on measurements of resistance fluctuations in the gas sensor, to study the effects of such modulation on the noise intensity for ambient atmospheres of synthetic air without and with additions of small amounts of ethanol,...
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Predicting the viscosity and electrical conductivity of ionic liquids on the basis of theoretically calculated ionic volumes
PublicationSelected physical properties of the ionic liquids might be quantitatively predicted based on the volumes of the ions these systems are composed of. It is demonstrated that the ionic volumes calculated using relatively simple theoretical quantum chemistry methods can be utilised to estimate the viscosities and electrical conductivities of various commonly used ionic liquids. The fitting formulas of the exponential form are offered...
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Miniaturized bandpass substrate integrated waveguide filter with frequency-dependent coupling realized using asymmetric GCPW discontinuity
PublicationAn asymmetric GCPW discontinuity is proposed to provide frequency-dependent coupling in microwave bandpass filters. Wider and narrow sections introduce, respectively, the capacitive and inductive component to the equivalent circuit representing coupling. By selecting the dimensions of the discontinuity and width of the inductive window in substrate integrated waveguide, an additional transmission zero can be introduced at prescribed...
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Dissociation of furan-2-carboxylic acid by low energy electrons
PublicationElectron attachment to molecular target can lead to a variety of negative fragment ions. We experi- mentally probe the main dissociative electron attachment channels in furan-2-carboxylic acid (C3H3O2 − COOH) - a molecular target composed of two important structural units: a furan ring and a carboxylic group. In our studies we utilise nearly mono-energetic electrons at electron energies from 0 eV up to 15 eV. Our detection setup...
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Methods of determination of C coefficient for period of rolling vessel in calm water for example of pax cargo ship
PublicationThis article presents a different approach to calculate the C coefficient needed to determine the period of own rolling vessel in calm water. The C coefficient is usually adopted as the approximate value from the available literature, usually depending on the type of vessel, and less dependent on the loading condition. In experimental studies of marine properties (seakeeping) often have a problem with the selection of the correct...
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Efficient synthesis and antifungal investigation of nucleosides’ quaternary ammonium salt derivatives
PublicationQuaternary ammonium salts are a group of compounds with diverse biological properties, the most important of which are their antiviral, antibacterial, and antifungal activities. The quaternization reactions of 5'-O-tosyl derivatives of uridine and thymidine with triethylamine, trimethylamine, 4-(N ,N -dimethylamino)pyridine, 2-methylpyridine, and pyridine are described in this article. Two of the synthesized compounds are exceptional...
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On adaptive selection of estimation bandwidth for analysis of locally stationary multivariate processes
PublicationWhen estimating the correlation/spectral structure of a locally stationary process, one should choose the so-called estimation bandwidth, related to the effective width of the local analysis window. The choice should comply with the degree of signal nonstationarity. Too small bandwidth may result in an excessive estimation bias, while too large bandwidth may cause excessive estimation variance. The paper presents a novel method...
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Properties of Nasicon-based CO2 sensors with Bi8Nb2O17 reference electrode
PublicationPotentiometric CO2 sensors based on Nasicon (Na+ conductor, Na3Zr2Si2PO12) electrolyte, Bi8Nb2O17/Pt reference electrode and different sensing electrodes have been prepared. Besides the sensing electrode material, sensors differ from each other in the reference electrode preparation technique. The main aim of this study is to investigate sensor construction and electrode fabrication process influence on sensor properties. The optimal...
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The Impact of Wind Generation on the Transmission System
PublicationThis article has been published to investigate the im-pact of the wind power on the power system- this is a system dependent issue that requires to perform sys-tem specific impact study. This paper discusses the impact of power flow, short circuit current, power quali-ty, voltage stability and the power system during the connection of a wind farm into transmission system. W referacie omówiono wpływ farm wiatrowych na pracę systemu...
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Deep learning approach on surface EEG based Brain Computer Interface
PublicationIn this work we analysed the application of con-volutional neural networks in motor imagery classification for the Brain Computer Interface (BCI) purposes. To increase the accuracy of classification we proposed the solution that combines the Common Spatial Pattern (CSP) with convolutional network (ConvNet). The electroencephalography (EEG) is one of the modalities we try to use for controlling the prosthetic arm. Therefor in this...
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Ferro- and antiferro-magnetism in (Np, Pu)BC
PublicationTwo new transuranium metal boron carbides, NpBC and PuBC, have been synthesized. Rietveld refinements of powder XRD patterns of {Np,Pu} BC confirmed in both cases isotypism with the structure type of UBC. Temperature dependent magnetic susceptibility data reveal antiferromagnetic ordering for PuBC below T-N = 44 K, whereas ferromagnetic ordering was found for NpBC below T-C = 61 K. Heat capacity measurements prove the bulk character...
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Continuous wave sonar with hyperbolic frequency modulation keyed by pseudo-random sequence
PublicationA CW FM type sounding signal is used in the classical solution of silent sonar. While the signal provides a relatively simple implementation of digital signal processing, and ensures good detection conditions, unfortunately, in the presence of the Doppler effect, distance measurement results tend to be wrong. This is due to the fact that the received signal’s instantaneous frequency value is dependent both on the distance to the...
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On mechanics of piezocomposite shell structures
PublicationThis study presents an original and novel investigation into the mechanics of piezo-flexo-magneto-elastic nanocomposite doubly-curved shells (PFMDCSs) and the ability to detect the lower and higher levels of electro-magnetic fields. In this context, by utilizing the first-order shear deformation shell model, stresses and strains are acquired. By imposing Hamilton's principle and the von Kármán approach, the governing equations...
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Thriving in multicultural workplace
PublicationThriving at work is defined as the psychological state that links both a sense of vitality and learning. The vitality component of thriving may be seen as positive energy, while learning enhances a sense of competence and efficacy. Thriving sheds new light on individual psychological functioning and the experience of growth in the work context. Thriving at work promotes growth through playing an active role in interaction with...
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Heat transfer in plate heat exchanger channels: experimental validation of selected correlation equations
PublicationThis study is focused on experimental investigation of selected type of brazed plate heat exchanger. The Wilson approach was applied in order to estimate heat transfer coefficients for the PHEx passages. The main aim of the paper was to experimentally check ability of several correlations published in the literature to predict heat transfer coefficients by comparison experimentally obtained data with appropriate predictions. The...
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Integrity level verification for safety-related functions
PublicationThis article describes methods for safety integrity level (SIL) verification of safety-related functions with regard to probabilistic criteria given international standards IEC 61508 and IEC 61511. These functions are to be realized using the electrical, electronic and programmable electronic (E/E/PE) systems or safety instrumented systems (SIS). Some methods are proposed for quantitative probabilistic modelling taking into account...
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Mercury in Different Feather Types from Great Cormorants (Phalacrocorax carbo L.) Inhabiting the Vistula Lagoon Ecosystem in Poland
PublicationTotal mercury levels in different feather types (down, contour, tail and flight) in Great Cormorants (Phalacrocorax carbo L.) were determined using CV-AAS. Feathers from Great Cormorants inhabiting the Vistula Lagoon ecosystem have an average Hg level of 7.14 ± 3.99 (μg/g w.w.). Age-dependent concentrations of Hg were statistically significant (ANOVA Kruskal-Wallis, p < 0.0001). There were also significant differences in Hg levels...
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Agents in Simulation of Cyberattacks to Evaluate Security of Critical Infrastructures
PublicationIn the last years critical infrastructures have become highly dependent on the information technologies and exposed to cyberattacks. Because the effects of the attacks can be detrimental, it is crucial to comprehensively asses the security of the infrastructures' information systems. This chapter describes MAlSim - the simulator of malicious software based on software agents, developed for the needs of a testbed for critical infrastructures...