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Combination of air-dispersion cathode with sacrificial iron anode generating Fe2+Fe3+2O4 nanostructures to degrade paracetamol under ultrasonic irradiation
PublicationIn the present study, ultrasound (US) was coupled with an electrochemical process (ECP) consisting of a novel cathode of carbon cloth (CC)-carbon black (CB) as the nano-composite air-dispersion cathode (NADC) for the degradation of paracetamol (APAP) in an aquatic medium. The NADC favored in situ production of H2O2 by the cathodic reduction. The implementation of iron sacrificial anode instead of dimensionally stable anodes resulted...
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Investigating the effects of structural pounding on the seismic performance of adjacent RC and steel MRFs
PublicationAn insufficient separation distance between adjacent buildings is the main reason for structural pounding during severe earthquakes. The lateral load resistance system, fundamental natural period, mass, and stiffness are important factors having the influence on collisions between two adjacent structures. In this study, 3-, 5- and 9-story adjacent reinforced concrete and steel Moment Resisting Frames (MRFs) were considered to investigate...
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Geographic Information System for Flood Hazard Analysis and Early Warning Using Numerical Weather Predictions
PublicationFloods are a phenomenon which causes significant losses of lives as well as property damage, which in turn severely impact the local economy. The nature of a flooding has been well researched, and several methods of flood hazard simulation have been established over the last decades. The current legislation in the European Union requires the Member States to create, maintain and update flood risk and hazard maps, as well as identify...
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Investigation of the antimicrobial potential and microbiota of bee pollen and bee bread derived from Polish apiaries
PublicationThe phenomenon of resistance of microorganisms to antibiotics is becoming one of the greatest challenges of modern medicine. At the same time, the number of new antibiotics introduced into clinical practice is decreasing. This creates the need to search for new, effective, non-antibiotic methods of combating and preventing infectious diseases. Over the last two decades, there has been renewed interest in the antimicrobial potential...
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Study on the Coastline Evolution in Sopot (2008–2018) Based on Landsat Satellite Imagery
PublicationThe coastline is the boundary between the water surface in a reservoir or watercourse and the land, which is characterised by high instability and functional diversity. For these reasons, research on coastal monitoring has been conducted for several decades. Currently, satellite images performed with synthetic aperture radars (SARs) are used to determine its course and variability together with high-resolution multispectral imagery...
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Horizontally-split-drain MAGFET - a highly sensitive magnetic field sensor
PublicationWe propose a novel magnetic field sensitive semiconductor device, viz., Horizontally-Split-Drain Magnetic-Field Sensitive Field-Effect Transistor (HSDMAGFET) which can be used to measure or detect steady or variable magnetic fields. Operating principle of the transistor is based on one of the galvanomagnetic phenomena and a Gradual Channel Detachment Effect (GCDE) and is very similar to that of Popovic and Baltes's SDMAGFET. The...
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Kagome Lattice Promotes Chiral Spin Fluctuations
PublicationDynamical spin fluctuations in magnets can be endowed with a slight bent toward left- or right-handed chirality by Dzyaloshinskii-Moriya interactions. However, little is known about the crucial role of lattice geometry on these chiral spin fluctuations and on fluctuation-related transport anomalies driven by the quantum-mechanical (Berry) phase of conduction electrons. Via thermoelectric Nernst effect and electric Hall effect experiments,...
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ATTEMPT AT EVALUATING THE INFLUENCE OF BENDING STRESS ON SHAFT WEAR PROCESSES IN WATER LUBRICATED SLIDING BEARING WITH A RUBBER BUSHING
PublicationWater lubricated bearings find increasingly wide application in shipbuilding or hydro–power industry, the popularity stemming from their numerous advantages. Unfortunately, as it turns out, water lubricated bearings do not always meet expectations, as on occasion they become subject to intense, premature wear which requires costly repair. One of the still unexplained phenomena is the process of excessive bearing wear, in particular...
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Estimation of the steam condensation flow via CFD methods
PublicationThe results of numerical simulations to predict the performance of different steam models have been presented. All of the considered models of steam condensation have been validated on the base of benchmark experiment employing expansion in nozzle and next on the low pressure part of the steam turbine stage. For numerical analysis three models have been finally used – the ideal steam model without condensation, an equilibrium steam...
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Visualizing spatially decomposed intermolecular correlations in the infrared spectra of aprotic liquids
PublicationInfrared (IR) spectroscopy is commonly used to study intermolecular interactions in the liquid phase, including solvation phenomena. On the other hand, ab initio molecular dynamics (AIMD) simulations offer the possibility to obtain IR spectra from first principles. Surpassing the experiment, AIMD simulations can deliver additional information on the spatial intermolecular correlations underlying the IR spectrum of the liquid. Although...
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Multiple reference frame theory in the synchronous generator model considering harmonic distortions caused by nonuniform pole shoe saturation
PublicationThe paper describes a synchronous generator model developed based on the multiple reference frame theory. The main physical phenomena included in the model are the machine armature non-sinusoidal voltage waveform and the influence of armature current in load conditions on the armature voltage waveform higher harmonic components. The modified multiple reference frame theory model is proposed. In this modified theory model the field...
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Flow Analysis of a Kaplan Turbine
PublicationThis monograph is a guide to a method of experimental and numerical flow investigations for Kaplan - type turbines. The numerical calculations were compared with the test results of the model Kaplan turbine. The tests were carried out on the model test rig in the Gdańsk University of Technology. The turbine has been thoroughly experimentally investigated, resulting in the identification of optimum setting combination of the stator...
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Evaluating Business Accelerator Participants’ Experiences – Effectuation at Play?
PublicationResponding to the new phenomena in entrepreneurship ecosystems in Poland, the author undertakes the study that aims to explore experiences of participants of (pre)accelerator programme for start-ups. Clipster is a business an acceleration and incubation programme, where participants have a unique co-living opportunity and work on their new venture ideas. With phenomenological interviews with six nascent entrepreneurs - participants...
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THE INFLUENCE OF THE URBAN DESIGN ON THE AIR EXCHANGE IN CITIES. SELECTED PROBLEMS IN POLISH REALITY
PublicationThe progress of the architecture and urbanism raises problems requiring interdisciplinary research conducted with the use of advanced experimental techniques and computer simulation. The fields of this research include aerodynamics, especially in intensively developed area of Environmental Wind Engineering (EWE). Aerodynamic phenomena occurring around buildings have a significant impact on the quality of the climate in the cities....
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Evaluating Business Accelerator Participants’ Experiences – Effectuation at Play?
PublicationResponding to the new phenomena in entrepreneurship ecosystems in Poland, the author undertakes the study that aims to explore experiences of participants of (pre)accelerator programme for start-ups. Clipster is a business an acceleration incubation programme, where participants have a unique co-living opportunity and work on their new venture ideas. With phenomenological interviews with six nascent entrepreneurs - participants...
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Experimental study of pressure rise at the evaporator of capillary pumped loop with acetone and water as working fluids
PublicationIn this work studied is the possibility of fluid pumping using capillary forces in the capillary pumped loop. Experimental and theoretical studies have been performed to understand the phenomena associated with heat transfer in porous structure of the evaporator. The capillary effect was studied during operation of two different capillary porous structures with two different working fluids, namely water and acetone. The results...
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Elderly persons professional activity - substantive issues and methodological challenges
PublicationPopulation ageing in Europe and mass withdrawal from professional activity leads to a number of adverse phenomena, such as increased public spending, reduced consumer demand and the growing problem of social exclusion. The study focuses on the problems of population ageing in Europe as well as on the feasible steps that may be taken with a view to professional activation of the elderly. The first part is concerned with the trends...
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The influence of reactions conditions on aggregation of dyes used in biochemistry
PublicationSelf-association of dyes and related substances is a very important phenomenon in many fields of applied chemistry. It is also fundamental model reaction of many kinds of molecular interactions such as the micelle formation of amphiphilic substances and the binding of small organic molecules to macromolecules. In spite of many studies concerning the dimerization equilibria of dyes and related substances, the mechanism seems not...
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Data-driven, probabilistic model for attainable speed for ships approaching Gdańsk harbour
PublicationThe growing demand for maritime transportation leads to increased traffic in ports. From this arises the need to observe the consequences of the specific speed ships reach when approaching seaports. However, usually the analyzed cases refer only to the statistical evaluation of the studied phenomenon or to the empirical modelling, ignoring the mutual influence of variables such as ship type, length or weather conditions. In this...
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Toward an understanding of occupational burnout among employees with autism – the Job Demands‑Resources theory perspective
PublicationThis article aims to gain insight into the phenomenon of occupational burnout among employees with autism based on the theoretical framework of the Job Demands-Resources theory and the literature on employees with autism in the workplace. Firstly, we argue that although the resources and demands of the neurotypical and neurodivergent employees might be different, the theoretical mechanism of occupational burnout formation remains...
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GPR investigation of the strengthening system of a historic masonry tower
PublicationIn this paper the condition assessment of the strengthening system of a masonry tower was carried out by the GPR method. The study provided unique experimental data acquired during measurements of the reinforced concrete frame embedded in masonry walls. Conducted numerical and experimental investigations were focused on the phenomenon of the diffraction-refraction scattering of the electromagnetic energy. A hyperbola resulting...
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Assessment of Supercapacitor’s Quality by Means of Low Frequency Noise
PublicationLow frequency noise is a well-known tool for quality and reliability assessment of electronic devices. This phenomenon is observed in different electrochemical devices as well (e.g., smart windows, electrochemical corrosion processes). Thus, we can assume that the same tool can be used to asses quality of supercapacitors. Their quality is usually determined only by capacitance and/or equivalent series resistance (ESR), or impedance....
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Barcelona - from the province to Metropolis.The cogent strategy of branding the city
PublicationThe phenomenon of rebranding Barcelona's image, called the Barcelona effect or 'Barcelona Model', is exampled as one of the most spectacular transformations of the city perception in the last decade. Why has Barcelona been successful? Is it the effect of the recently intensified revitalization practice, or has the city of Barcelona built its brand market value for years? The aim of the research is to name these transition...
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Peripheral industrial NUTS 3 sub-regions in the European Union – identification and typology
PublicationA common phenomenon of development is the big difference in its levels, especially between metropolitan and non-metropolitan areas. Non-metropolitan areas are also very different. In some of them, industry plays a big role. European Union’s NUTS 3 non-metropolitan low developed sub-regions, whose gross domestic product per capita in 2011 was below 75% of the EU average, were the subject of research. It is based on the data and...
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Structure and performance properties of environmentally-friendly biocomposites based on poly(ɛ-caprolactone) modified with copper slag and shale drill cuttings wastes
PublicationThe potential application of two types of industrial wastes, drill cuttings (DC) and copper slag (CS), as silica-rich modifiers of poly(ɛ-caprolactone) (PCL) was investigated. Chemical structure and physical properties of DC and CS fillers were characterized using X-ray diffractometer, X-ray fluorescence spectroscopy, particle size and density measurements. PCL/DC and PCL/CS composites with a variable content of filler (5 to 50...
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Optical Detection of Ketoprofen by Its Electropolymerization on an Indium Tin Oxide-Coated Optical Fiber Probe
PublicationIn this work an application of optical fiber sensors for real-time optical monitoring of electrochemical deposition of ketoprofen during its anodic oxidation is discussed. The sensors were fabricated by reactive magnetron sputtering of indium tin oxide (ITO) on a 2.5 cm-long core of polymer-clad silica fibers. ITO tuned in optical properties and thickness allows for achieving a lossy-mode resonance (LMR) phenomenon and it can be...
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Influence of Bitumen Type and Asphalt Mixture Composition on Low-Temperature Strength Properties According to Various Test Methods
PublicationIn regions with low-temperatures, action transverse cracks can appear in asphalt pavements as a result of thermal stresses that exceed the fracture strength of materials used in asphalt layers. To better understand thermal cracking phenomenon, strength properties of different asphalt mixtures were investigated. Four test methods were used to assess the influence of bitumen type and mixture composition on tensile strength properties...
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Detection of anomalies in bee colony using transitioning state and contrastive autoencoders
PublicationHoneybees plays vital role for the environmental sustainability and overall agricultural economy. Assisting bee colonies within their proper functioning brings the attention of researchers around the world. Electronics systems and machine learning algorithms are being developed for classifying specific undesirable bee behaviors in order to alert about upcoming substantial losses. However, classifiers could be impaired when used...
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A note on the applications of artificial intelligence in the hospitality industry: preliminary results of a survey
PublicationIntelligent technologies are widely implemented in different areas of modern society but specific approaches should be applied in services. Basic relationships refer to supporting customers and people responsible for services offering for these customers. The aim of the paper is to analyze and evaluate the state-of-the art of artificial intelligence (AI) applications in the hospitality industry. Our findings show that the major...
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State Interventionism in Tax System - Example of Action in a COVID-19 Crisis
PublicationThe following article presents and classifies changes in tax systems of selected countries as well as counts them as the response to the emergence of the crisis caused by the COVID-19 pandemic. Such actions were undertaken the context of state interventionism in the tax system. In order to achieve the objective of presenting the state interventionism in the context of tax rates, an analysis of the literature on the phenomenon described,...
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Tax Evasion, Tax Morale, and Trade Regulations: Company-Level Evidence from Poland
PublicationObjective: To investigate the determinants of the phenomenon of evading taxes among polish entrepreneurs. In particular, I examine such factors as tax administration satisfaction, tax morale, tax burden, and the influence of trade regulations. Research Design & Methods: A survey study conducted in 2017 in Poland among 454 enterprises. I used the zero-inflated negative binomial modelling technique to examine the impact of factors...
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Processing, physico-mechanical and thermal properties of reclaimed GTR and NBR/reclaimed GTR blends as function of various additives
PublicationIn this work, ground tire rubber (GTR) was mechano-chemically reclaimed in the presence of bitumen and various additives. During studies three types of processing and curing additives: (i) peptizer P300; (ii) vulcanization accelerator tetramethylthiuram disulfide (TMTD) and (iii) organic peroxide di(2-tert-butyl-peroxyisopropyl)benzene (BIB1) were applied to enhance reclaiming of GTR. Reclaiming process was evaluated by oscillating...
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Aerodynamic Shape Optimization for Delaying Dynamic Stall of Airfoils by Regression Kriging
PublicationThe phenomenon of dynamic stall produce adverse aerodynamic loading which can adversely affect the structural strength and life of aerodynamic systems. Aerodynamic shape optimization (ASO) provides an effective approach for delaying and mitigating dynamic stall characteristics without the addition of auxiliary system. ASO, however, requires multiple evaluations time-consuming computational fluid dynamics models. Metamodel-based...
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Coupling between Blood Pressure and Subarachnoid Space Width Oscillations during Slow Breathing
PublicationThe precise mechanisms connecting the cardiovascular system and the cerebrospinal fluid (CSF) are not well understood in detail. This paper investigates the couplings between the cardiac and respiratory components, as extracted from blood pressure (BP) signals and oscillations of the subarachnoid space width (SAS), collected during slow ventilation and ventilation against inspiration resistance. The experiment was performed on...
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Interfacially modified LDPE/GTR composites with non-polar elastomers: From microstructure to macro-behavior
PublicationThis paper provides some new insights into the mechanism of interaction and modifications in thermoplastic composites based on low density polyethylene (LDPE), ground tire rubber (GTR) and non-polar elastomer. The composites were prepared using a co-rotating twin-screw extruder at variable LDPE/GTR ratio and constant elastomer content. Two types of commercial elastomer were applied: styrene-butadiene-styrene (SBS) block copolymers (Kraton®)...
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Natural convective heat transfer from isothermalconic
PublicationTheoretical considerations on convective heat transfer from isothermal upward conicalsurfaces have been presented. The physical model of this phenomenon consists of an isothermalcone of inclination angle (φ) between the cone generating line (X) and the radius (R) of the cone base. The angle is a parameter of conical surface which varied from (φ = 0−circular horizontal plate) to (φ = π/2—vertical cylinder) . Onthe basis of Navier–Stokes...
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A current-controlled FET
PublicationA novel semiconductor device, viz., Horizontally-Split-Drain Current-Controlled Field-Effect Transistor (HSDCCFET) with two control electrodes is proposed in this works. For the sake of brevity, the device can be called a CCFET. Operating principle of the proposed transistor is based on one of the galvanomagnetic phenomena, the Biot-Savart-Laplace law and a Gradual Channel Detachment Effect (GCDE). The transistor is dedicated...
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Analysis of the structure of the atomized fuel spray with marine diesel engine injector in the early stage of injection
PublicationThis paper presents the results of the experimental research of the atomized fuel spray with the marine diesel engine injector in the constant volume chamber. The specificity of the phenomena occurring in the marine engine cylinder was the reason to use the optical visualisation method in the studies – the Mie scattering technique. This work presents an analysis of the influence of different geometry of outlet orifice and opening...
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Hybrid model of geared rotor system
PublicationIn the paper a hybrid model of a geared multirotor system has been developed. The model is obtained by application of both the modal decomposition methodology and the spatial discretization method. Reduced modal model was constructed for the system without gyroscopic and damping effects. The gyroscopic interaction, damping and other phenomena which are difficult to include in the modal approach were modeled by application of simply...
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High-quality Experiment Dedicated to microGravity Exploration, Heat Flow and Oscillation Measurement from Gdańsk
PublicationIn this paper we propose HEDGEHOG (High-quality Experiment Dedicated to microGravity Exploration, Heat flow and Oscillation measurement from Gdańsk) REXUS experiment to investigate vibrational and heat flow phenomena during the whole (ascent, microgravity phase, descent and recovery) flight of a sounding rocket. First, a proposed system of cantilever beams is discussed to study dynamic behaviour of dummy payload. Dimensioning has...
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Analysis and Comparison of Safety of Children and Adult Passenger in Car Based on Crash Tests Results
PublicationMost important features of the child seat were presented. There was made analysis of selected dynamic loads acting on mannequins heads during a collision. Comparison of loads acting on the kid in a child seat and the other passengers in a car is presented. In analysis of the results particular attention has been paid on the children's secure in a car. The phenomena of collision child's occipital bone with seat backrest was described....
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Preliminary studies on the effect of feed speed on the colour change of wood
PublicationThis paper presents the results of preliminary analyses of the effect of cutting parameters on changes in the colour of wood. Beech wood cut with use circular saw was analysed. The cutting parameter tested was the feed speed, represented by the feed per tooth. Sawing processes with different feed per tooth ranging from 0.0008 mm to 0.09 mm were analysed. It was observed that over the entire range of feed rate per tooth analysed,...
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Tracking Fluorescent Dye Dispersion from an Unmanned Aerial Vehicle
PublicationCommercial unmanned aerial vehicles continue to gain popularity and their use for collecting image data and recording new phenomena is becoming more frequent. This study presents an effective method for measuring the concentration of fluorescent dyes (fluorescein and Rhodamine WT) for the purpose of providing a mathematical dispersion model. Image data obtained using a typical visible-light camera was used to measure the concentration...
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The effect of cable duct diameter on the ampacity of high-voltage power cables
PublicationThe ampacity of power cables depends, among others, on the conditions of heat dissipation from the cable to the environment. Cables are usually laid directly in the ground, but in some sections, they may be placed in ducts, which adversely affects the ampacity of the cable line. The paper presents heat transfer phenomena for cables installed in pipe-type ducts filled with air. The effect of cable duct diameter on this ampacity...
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Ultrawideband transmission in physical channels: a broadband interference view
PublicationThe superposition of multipath components (MPC) of an emitted wave, formed by reflections from limiting surfaces and obstacles in the propagation area, strongly affects communication signals. In the case of modern wideband systems, the effect should be seen as a broadband counterpart of classical interference which is the cause of fading in narrowband systems. This paper shows that in wideband communications, the time- and frequency-domain...
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Guided waves for nondestructive diagnostics of embedded waveguides
PublicationThe thesis concentrates on comprehensive theoretical, numerical and experimental analysis of guided wave propagation in bars embedded in concrete or mortar. The investigations are focused on a particular type of objects representing a laboratory model of a ground anchor. Complex description of wave propagation phenomena in partially embedded bars is given and its application in...
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High Frequency Conducted Emission in AC Motor Drives Fed By Frequency Converters: Sources and Propagation Paths
PublicationProvides a concise and thorough reference for designing electrical and electronic systems that employ adjustable speed drives Electrical and electronic systems that employ adjustable speed drives are being increasingly used in present-day automation applications. They are considered by many application engineers as one of the most interfering components, especially in a contemporarily faced industrial environment. This book fills...
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Marine and Cosmic Inspirations for AI Algorithms
PublicationArtificial Intelligence (AI) is a scientific area that currently sees an enormous growth. Various new algorithms and methods are developed and many of them meets practical, successful applications. Authors of new algorithms draw different inspirations. Probably the most common one is the nature. For example, Artificial Neural Networks were inspired by the structure of human brain and nervous system while the classic Genetic Algorithm...
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NUMERYCZNY MODEL OBLICZENIOWY OBIEGU TURBINY KLASY 300 MW
PublicationNiniejszy artykuł stanowi opis modelu obiegu cieplnego turbiny o mocy 360MW, utworzonego w preprocesorze numerycznego programu obliczeniowego onazwie DIAGAR. Zadaniem opisywanego modelu jest odtwarzanie zjawisk fizycznych zachodzących w poszczególnych urządzeniach składowych obiegu, zarówno podczas poprawnej (sprawnej) pracy bloku energetycznego, jak i w przypadku pojawienia się niesprawności. Utworzony...
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Remarks on steam condensation modeling related to steam turbine large output
PublicationIn the paper numerical simulations have been performed to predict the performance of the diferent steam models. All of the considered models of steam condensation have been validated on the base of benchmark experiment employing expansion in nozzle and next on the low pressure part of the steam turbine equipped with the so-called Baumann stage. For numerical analysis three models have been finally used - the ideal steam model without...