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Current issues of functional safety and cybersecurity analysis of the industrial and critical infrastructures
PublicationThis article addresses some functional safety assessment procedures with cybersecurity aspects in critical industrial installations with regard to the functional safety requirements specified in standards IEC 61508 and IEC 61511. The functional safety management includes hazard identification, risk analysis and assessment, specification of overall safety requirements and definition of safety functions. Based on the risk assessment...
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The effect of the late wood share in the annual ring growth on the cutting power
PublicationW pracy przedstawiono wpływ udziału drewna późnego w przyroście rocznym na zapotrzebowanie mocy skrawania na jedną piłę podczas przecinania drewna sosnowego na pilarce ramowej PRW15-M. Drewno sosnowe pochodziło z 4. Krain Geograficznych Polski. Otrzymane wyniki poddano analizie statystycznej, która wykazała, że dla większości Krain korelacja pomiędzy udziałem drewna późnego w przyroście rocznym i mocą skrawania była znacząca na...
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Behavior of residual current devices at earth fault currents with DC component
PublicationLow-voltage electrical installations are increasingly saturated with power electronic converters. Due to very high popularity of photovoltaic (PV) installations and the spread of electric vehicles (EV) as well as their charging installations, DC–AC and AC–DC converters are often found in power systems. The transformerless coupling of AC and DC systems via power electronic converters means that an electrical installation containing...
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Potential applications of crude glycerol in polymer technology–Current state and perspectives
PublicationThe increasing use of bio-based fuels and fuel additives, among them biodiesel, causes significant surplus of crude glycerol on the market which creates new challenges in terms of its sustainable utilization. A lot of ways for the incorporation of this by-product into different branches of industry requires purification by expensive and complicated processes. Therefore, researchers are seeking for applications of untreated crude...
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Calculations of Short-Circuit Current Flows in Earth Wires of HV Lines
PublicationThis paper presents a method which enables calculating flows of short-circuit currents in earth wires of high voltage transmission lines, and its implementation in the form of a computer programme. The algorithm enables performing calculations for a double-fed line and starconnected lines (three terminal lines). The developed programme enables verifying dimensioning of earth wires in the context of their short-circuit thermal withstand...
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Methodology for determination of the selected mechanical properties of wood based on cutting tests
PublicationFrom kiln-dried spruce wood (with steam) as well as in natural conditions were randomly selected 8 samples. After determining the average dimensions, moisture content and density of the samples they have been cut on the frame sawing machine PRW15M for measurement of cutting power. Based on those results from a linear rela-tionship of cutting power versus feed per toot mechanical properties of wood such as facture toughness and...
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Good sleep and exhausting work-efforts, burnout and insomnia in nursing profession
PublicationThe role of insomnia in burnout syndrome among nurses - empirical study
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Comprehensive compensation of grid current distortion by shunt active power filters
PublicationThe paper presents a comprehensive approach to the compensation of grid current distortion in shunt active power filter systems. Four sources of current distortion are addressed: imperfect grid synchronization caused by the distortion in the grid voltages, time delays in the evaluation of grid voltages and computation of compensating currents, fluctuations of the dc bus voltage, and the distortion of inverter output voltages due...
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Spurring the community involvement in planning - lessons from post-socialist cities
PublicationPublic participation and community involvement in planning processes is – in general – not a new topic for contemporary planners. But in many parts of the world – including the post-socialist countries like Poland or Russia – we can still face the lack of understanding of importance of proper community involvement in planning and development processes. Situation in these countries is significantly different from both highly-developed...
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Automated Diagnostics of Current Pick-Up Disturbances in Electric Traction Networks
PublicationThe present work defines the basic causes of bow disturbances of current pick-up, sets a task of establishing a system of automated control of bow disturbances at feeder zones of electric traction networks, proposes structural variants of the technical system implementation, describes the algorithm of detection of bow disturbances of current pick-up.
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Local dynamics of fluids and dielectrics as the foundation of signal-carrying wave properties
PublicationThis paper develops an original approach to fundamental problems of classical linear acoustics and electromagnetics, proving a crucial role of doubly-dynamic local properties of a propagation medium in supporting wave-like fields able to carry information signals. The proof is composed of two steps concerning, subsequently, fluid acoustics and dielectric electromagnetics. The first step consists in complementing a common, practically...
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The fundamentals of narrow-kerf sawing; the mechanics and quality of cutting / K. A. Orłowski.
PublicationW pracy przedstawiono ekonomiczne i ekologiczne uwarunkowania dokładnego przecinania drewna za pomocą pił cienkich (o niewielkiej wartości rzazu). Opisano współczesne technologie wykorzystujące cienkie piły: pilarki tarczowe wielopiłowe, pilarki taśmowe i ramowe. W rozdziale drugim omówiono siły skrawania w ujęciu klasycznym, w którym do ich szacowania przyjmuje się przede wszystkim wartości właściwego powierzchniowego oporu skrawania,...
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IPMSM rotor position estimator based on analysis of phase current derivatives
PublicationThis paper describes an algorithm for estimation of IPMSM angular rotor position. The algorithm uses derivatives of motor phase currents resulting from PWM modulation to obtain the rotor position. The presented method is designed for medium- and high-speed range, since it is based on determination of the EMF vector. Algorithm is characterised by a very simple formulae. The calculation of rotor position is performed in every PWM...
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Current trends in the field of steganalysis and guidelines for constructions of new steganalysis schemes
PublicationThe paper concerns blind steganalysis techniques in the passive steganalysis scenario designed to detect the steganographic cover modification schemes. The goal is to investigate the state-of-art in the field of steganalysis, and, above all, to recognize current trends existing in this field and determine guidelines for constructions of new steganalysis schemes. The intended effects are to examine the possibilities for the development...
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Application of ionic liquids in microextraction techniques: Current trends and future perspectives
PublicationIonic liquids (ILs) with their unique properties found so far numerous analytical applications. Among them ILs both in their liquid form and immobilized on the surface or within the pores of a solid support were successfully utilized in microextraction techniques. The scope of this review will cover a comprehensive summarizing of available literature data on selected properties of ILs playing a key role in analytical purposes,...
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Nonlinear Control of a Doubly Fed Generator Supplied by a Current Source Inverter
PublicationNowadays, wind turbines based on a doubly fed induction generator (DFIG) are a commonly used solution in the wind industry. The standard converter topology used in these systems is the voltage source inverter (VSI). The use of reverse-blocking insulated gate bipolar transistor (RB-IGBT) in the current source inverter topology (CSI), which is an alternative topology, opens new possibilities of control methods. This paper presents...
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Artificial-Hand Technology—Current State of Knowledge in Designing and Forecasting Changes
PublicationThe subject of human-hand versatility has been intensively investigated for many years. Emerging robotic constructions change continuously in order to mimic natural mechanisms as accurately as possible. Such an attitude is motivated by the demand for humanoid robots with sophisticated end effectors and highly biomimic prostheses. This paper provides wide analysis of more than 80 devices that have been created over the last 40 years....
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Corporate Social Responsibility and Family Business: Current Debates and Future Prospects
PublicationThis paper aims at examining the main perspectives on corporate social responsibility (CSR) in family firms discussed in international literature. The topic of CSR has grown exponentially in the last two decades in both, business practice and as an area of interest among academics and researchers. Most studies focus on multinational corporations, some on small and medium enterprises (SMEs) and the smallest number on family business...
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Dead-Time Effect Compensation Based on Additional Phase Current Measurements
PublicationThis paper proposes a new method of dead-time effect compensation. The proposed solution is based on additional phase current measurements realized by analog-to-digital converters. These measurements are carried out at the time instants specified by a pulsewidth-modulation (PWM) strategy. This makes it possible to estimate inverter currents at the commutation instants and, finally, to estimate the voltage error caused by dead time. This...
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Method of sacrificial anode dual transistor-driving in stray current field
PublicationIn order to control a magnesium anode in a stray current interference field, a dual transistor driving system has been proposed. It consisted of a combination of PNP and NPN transistors. Dual transistor driven system and direct anode to cathode connection were electrochemically tested in 3% NaCl solution. The dual transistor driven system increased the anode efficiency and reduced hydrogen evolution and the risk of embrittlement....
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AN ALTERNATIVE WAY OF DETERMINING MECHANICAL PROPERTIES OF WOOD BY MEASURING CUTTING FORCES
PublicationThe cutting force is an energetic effect of splitting material, and might be therefore considered from a point of view of modern fracture mechanics. The dedicated mathematical model developed for description of the wood cutting has been developed here on the base of fracture theory, and includes work of separation (fracture toughness) in addition to the material plasticity and friction. The effect of the cutting edge dullness is...
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Feedback Control of Doubly-Fed Generator Connected to Current Source Converter
PublicationDoubly-fed induction generator (DFIG) system supplied by current source converter (CSC) is considered in this article. The DFIG can work in two independent modes: AC grid connection and stand-alone mode. The DFIG is connected to the ac grid directly through its stator and the CSC links the rotor side. In this mode, the active and reactive powers of the DFIG must be controlled. This article proposes two control system structures...
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Requirements for Residual Current Devices Intended for Electric Vehicle Charging Systems
PublicationThe properties of residual current devices have been presented from the point of view of their ability to detect a specific shape of the residual current waveform. Moreover, the standard requirements relating to residual current protection used in electric vehicle charging installations have been pointed out. The operating characteristics of the IC-CPD and RDC-DD protections, which are intended for charging electric vehicles in...
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Orbital blowout trauma occurring at the workplace – clinical, biomechanical and legal aspects
PublicationIntroduction and objective: Craniofacial injury at the workplace may lead to orbital blowout fractures. The aim of the study is the development of own numerical model of the eye orbit, assessment of the damage zones, and comparing them with clinical examinations. In addition, the current legal status of patients after injuries is presented Material and methods: In laboratory tests performed on bones collected from the upper and...
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Optimal segmented dampers configuration for a laminar body carrying variable payload
PublicationPublikacja prezentuje zagadnienia analizy doboru tłumienia i konfiguracji elementów tłumiących dla ciała płaskiego poddanego dwóm stanom obciążenia. W pracy zaakceptowano użycie elementów tłumiących o tłumieniu wiskotycznym i o współczynniku tłumienie zależnym od położenia tłoka tego elementu. Ponieważ różne aspekty komfortu prowadzą do przeciwnych wytycznych odnośnie wyboru własności tłumiących, rozwiązanie dobory parametrów tłumienia...
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Cut layer of a circular saw with radiaj run-out of cutting edges
PublicationW pracy przedstawiono analizę wpływu bicia promieniowego ostrzy piły tarczowej na zmianę nominalnego i całkowitego pola przekroju warstwy skrawanej.
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Natural sweeteners: Sources, extraction and current uses in foods and food industries
PublicationFood producers have leaned towards alternative natural and synthetic sweeteners in food formulations to satisfy market demands. Even so, several synthetic sweeteners (e.g., aspartame, saccharin, sucralose) are becoming less popular due to health-related concerns, lower nutritional values, and controversies around their safety. Conversely, natural sweeteners confer favourable customer perceptions due to their association to a healthier...
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Sustainability reporting in the airline industry: Current literature and future research avenues
PublicationSustainability reporting (SR) allows organisations to communicate their non-financial impacts to stakeholders. It has also become a widespread business practice in aviation, a transport sector that contributes significantly to global warming. Academia has begun to examine SR in the context of airlines surprisingly late, and no comprehensive reviews of its respective developments have been made so far. Consequently, a systematic...
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A versatile analog CMOS cell: voltage - buffer /current - conveyor/ multiplier
PublicationW pracy przedstawiono koncepcję uniwersalnej komórki analogowej przeznaczonej dla programowalnych układów analogowych (FPAA). Komórka może pełnić funkcję bufora napięciowego, konwjora prądowego lub mnożnika analogowego. Układ przesymulowano w technologii CMOS 2 ćm.
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Investigations of non-uniform structure of the tetacene layer by photoen-hanced current
PublicationBadano stany pułapkujące nośniki w powierzchniowych obszarach warstwy tetra-cenu. W badaniach wykorzystano metodę prądów fotowzmocnionych. Wykazano obe-cność różnych rozkładów energetycznych pułapek przy obu powierzchniach war-stw tetracenu.
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Theoretical analysis of current induced by high-energetic radiation in dielectric materials
PublicationW pracy poddano analizie mechanizmy generacji i rekombinacji nośników ładunku w obecności wysokoenergetycznego promieniowania. Przedstawiono zależności gęstości prądu elektrycznego od natężenia promieniowania i napięcia polaryzujacego próbkę.
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Effect of contactless hybrid current limiter on voltage dips in power system
PublicationW referacie przedstawiono działanie hybrydowego niskonapięciowego ogranicznika prądu zwarciowego, składającego się z ultraszybkiego bezpiecznika, tranzystora mocy i warystora. W szczególności omówiono możliwości polepszenia jakości dostarczanej do odbiorców energii elektrycznej. Zastosowanie hybrydowego ogranicznika prądu znacznie ogranicza czasy trwania zapadów napięcia w systemie elektroenergetycznym. Obliczenia wykonano przy...
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Effect of contactless hybrid current limiter on voltage dips in power system.
PublicationW referacie przedstawiono działanie hybrydowego niskonapięciowego ogranicznika prądu zwarciowego, składającego się z ultraszybkiego bezpiecznika, tranzystora mocy i warystora. W szczególności omówiono możliwości polepszenia jakości dostarczanej do odbiorców energii elektrycznej. Zastosowanie hybrydowego ogranicznika prądu znacznie ogranicza czasy trwania zapadów napięcia w systemie elektroenergetycznym. Obliczenia wykonano przy...
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Magnetic field effects on emission and current in Alq3 - based electroluminescent devices.
PublicationW pracy zaobserwowano stromy wzrost natężenia elektroluminescencji w polach magnetycznych nie przekraczających 300mT. Efekt ten wywołany jest magnetyczno polową redukcją stopnia zmieszania singletowych i trypletowych par elektron dziura, wymuszonego przez nadsubtelne oddziaływanie spinów elektronowych z ich otoczeniem jądrowym.
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Photoenhanced current as a tool for investigating non-uniform structures of tetracene layer.
PublicationPowierzchniowe prądy fotowzmocnione używane były jako narzędzie do badań fizycznych własności powierzchni warstw od strony podłoża, a także od strony przeciwległej podłożu.
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Detection of stray current field interference on metal constructions using STFT
PublicationZaprezentowano metodę detekcji pola prądów błądzących wykorzystującą krótkoczasową transformatę Fouriera STFT. Ten sposób analizy umożliwia wyznaczenie zmian spektralnej gęstości mocy sygnału (np. potencjału konstrukcji) w funkcji czasu. Przedstawiono rezultaty analizy zmian potencjału w polu prądów błądzących generowanych przez trakcję tramwajową. Spektrogramy są kompozycją prążków w łącznej dziedzinie czasu i częstotliwości....
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Current mechanisms of IGP routing - expectations and possibilities in terms of QoS constraints
PublicationOd mechanizmów rutingu oczekuje się nowych możliwości z chwilą wprowadzenia wymagań QoS. W tym kontekście aktualne techniki rutingu IGP nie oferuja rozwiązań określających ścieżki gwarantujące QoS. W pracy przedstawiono propozycję rozszerzenia OSPF, które umożliwia uwzględnienie ograniczeń wynikających z QoS, gwarantując jednocześnie usługi na żądanym poziomie. To rozszerzenie zawiera zarówno liniowe jak i nieliniowe metryki. Wartości...
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Evaluation of the stiffness modulus and phase angle of cold in-place recycled mix-tures for long curing periods
PublicationArticle presents the changes inbehaviour of cold-in place recycling mixtures made using cement and bituminous emulsion (CIR mixtures) after anelongated time of curing. Most of the available literatureregarding change instiffness modulus and phase angle presents resultsfor a maximum of several dozen days,which makesit difficult to predict the behaviour over the whole life of the compacted layer. The article...
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Qualitative characteristics and comparison of volatile fraction of vodkas made from different botanical materials by comprehensive two-dimensional gas chromatography and the electronic nose based on the technology of ultra-fast gas chromatography
PublicationBACKGROUND Vodka is a spirit-based beverage made from ethyl alcohol of agricultural origin. At present, increasingly more vodka brands have labels that specify the botanical origin of the product. Until now, the techniques for distinguishing between vodkas of different botanical origin have been costly, time-consuming and insufficient for making a distinction between vodka produced from similar raw materials. Therefore, it is...
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Characteristics of Cucumis metuliferus, Actinidia deliciosa and Musa paradisica fragrance profiles using a comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometric detection (GC×GC-TOF MS)
PublicationComprehensive two-dimensional gas chromatography with time-of-flight mass spectrometric detection (GC×GC-TOF-MS) is a modern analytical technique used in many fields. This technique enables an effective separation of volatile chemical compounds [1]. In recent years, the topic of healthy food and healthy living has become very popular. For this reason, more and more scientific publications related to the analysis of food products...
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Thermo-mechanical reclaiming of ground tire rubber via extrusion at low temperature: Efficiency and limits
PublicationThermomechanical reclaiming of ground tire rubber (GTR) was performed at different temperatures (60, 120, and 180°C) using a co-rotating twin-screw extruder. Obtained samples were used in styrene-butadiene rubber (SBR) blends. As reference samples, SBR compounds containing untreated GTR were used. Curing characteristics, static and dynamic mechanical properties, and morphology of the obtained blends were determined. The results...
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The Development of Anammox and Chloroflexi Bacteria during the Composting of Sewage Sludge
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From evil demiurge to caring hero: Images of geneticists in the movies
PublicationAlthough images of science and scientists depicted in popular culture have been criticized as an exaggeration and fear mongering, the cinema is an important resource that influences individuals’ beliefs about science. Because popular depictions of science play a crucial role in constructing the public’s ‘scientific imaginary’ they constitute an inherent dimension of the social understanding of science and are as important for...
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Different Modes of Hydrogen Peroxide Action During Seed Germination
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Benign Acute Childhood Myositis During Influenza B Outbreak
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The effects of ischemia during rest intervals on strength endurance performance
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Sympathetic neural responses to coronary occlusion during balloon angioplasty
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Military Food Supply Chain during the COVID-19 Pandemic
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DISPLACEMENT MEASUREMENTS DURING LOAD TESTING OF THE RAILWAY ARCH BRIDGE
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THE DETERMINANTS OF ENTERPRISE PROFI TABILITY DURING REDUCED ECONOMIC ACTIVITY
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