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Rok 2021
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Strength analysis of container ship subjected to torsional loading
PublikacjaThe objective of this work is to investigate the torsional response of a container ship, with particular consideration of the warping effect. Two different models are investigated. In the first case, the full length model of a ship is analyzed and a distributed load is applied with the use of a novel approach. The model is supported in the torsional centre of the cross-section, which is derived analytically. In the second case,...
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Structural and Material Determinants Influencing the Behavior of Porous Ti and Its Alloys Made by Additive Manufacturing Techniques for Biomedical Applications
PublikacjaOne of the biggest challenges in tissue engineering is the manufacturing of porous structures that are customized in size and shape and that mimic natural bone structure. Additive manufacturing is known as a sufficient method to produce 3D porous structures used as bone substitutes in large segmental bone defects. The literature indicates that the mechanical and biological properties of scaffolds highly depend on geometrical features...
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Study of a Multicriterion Decision-Making Approach to the MQL Turning of AISI 304 Steel Using Hybrid Nanocutting Fluid
PublikacjaThe enormous use of cutting fluid in machining leads to an increase in machining costs, along with different health hazards. Cutting fluid can be used efficiently using the MQL (minimum quantity lubrication) method, which aids in improving the machining performance. This paper contains multiple responses, namely, force, surface roughness, and temperature, so there arises a need for a multicriteria optimization technique. Therefore,...
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Study of Non-Newtonian biomagnetic blood flow in a stenosed bifurcated artery having elastic walls
PublikacjaFluid structure interaction (FSI) gained attention of researchers and scientist due to its applications in science felds like biomedical engineering, mechanical engineering etc. One of the major application in FSI is to study elastic wall behavior of stenotic arteries. In this paper we discussed an incompressible Non-Newtonian blood fow analysis in an elastic bifurcated artery. A magnetic feld is applied along x direction. For...
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Study on Dry Sliding Wear and Friction Behaviour of Al7068/Si3N4/BN Hybrid Composites
PublikacjaHybrid aluminium metal matrix composites have the potential to replace single reinforced aluminium metal matrix composites due to improved properties. Moreover, tribological performance is critical for these composites, as they have extensive application areas, such as the automotive, aerospace, marine and defence industries. The present work aims to establish the tribological characteristics of Al7068/Si3N4/BN hybrid metal matrix...
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Study on Microstructural Characterization, Mechanical Properties and Residual Stress of GTAW Dissimilar Joints of P91 and P22 Steels
PublikacjaThis article deals with the dissimilar joining of two different grade Cr-Mo steel (2.25Cr-1Mo: P22 and modified 9Cr-1Mo: P91) for power plant application. The dissimilar butt-welded joint was produced for conventional V groove design by using the gas tungsten arc welding (GTAW) process with the application of an ERNiCrMo-3 Ni-based super alloy filler. A microstructure characterization was performed to measure the inhomogeneity...
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Study on Microstructure and Mechanical Properties of Laser Welded Dissimilar Joint of P91 Steel and INCOLOY 800HT Nickel Alloy
PublikacjaThis investigation attempts to explore the weld characteristics of a laser welded dissimilar joint of ferritic/martensitic 9Cr-1Mo-V-Nb (P91) steel and Incoloy 800HT austenitic nickel alloy. This dissimilar joint is essential in power generating nuclear and thermal plants operating at 600–650 °C. In such critical operating conditions, it is essential for a dissimilar joint to preserve its characteristics and be free from any kind...
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Surface Roughness Evaluation in Thin EN AW-6086-T6 Alloy Plates after Face Milling Process with Different Strategies
PublikacjaLightweight alloys made from aluminium are used to manufacture cars, trains and planes. The main parts most often manufactured from thin sheets requiring the use of milling in the manufacturing process are front panels for control systems, housing parts for electrical and electronic components. As a result of the final phase of the manufacturing process, cold rolling, residual stresses remain in the surface layers, which can influence...
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Surface Texture after Turning for Various Workpiece Rigidities
PublikacjaIn the paper, we present an analysis of the surface texture of turned parts with L/D (length/diameter) ratios of 6 and 12 and various rigidity values. The studies were carried out on samples made of S355JR steel and AISI 304 stainless steel. A detailed analysis of 2D surface profiles was carried out by using a large number of parameters that allowed us to distinguish significant differences in the surface microgeometry, which confirmed...
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Technical and Economic Analysis of the Supercritical Combined Gas-Steam Cycle
PublikacjaCombined cycle power plants are characterized by high efficiency, now exceeding 60%. The record-breaking power plant listed in the Guinness Book of World Records is the Nishi-Nagoya power plant commissioned in March 2018, located in Japan, and reaching the gross efficiency of 63.08%. Research and development centers, energy companies, and scientific institutions are taking various actions to increase this efficiency. Both the gas...
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TEST METHOD FOR DETERMINING THE CHEMICAL EMISSIONS OF A MARINE DIESEL ENGINE EXHAUST IN OPERATION
PublikacjaThe article briefly describes the problem of air pollution caused by sea-going ships and the resulting restrictions on the emission of toxic and harmful chemical compounds in the exhaust of marine engines, introduced by the International Maritime Organization (IMO) under the International Convention for the Prevention of Sea Pollution from Ships (MARPOL 73/78). Such emissions provide a significant metrological problem, not only...
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The Chemical and Biological Properties of Nanohydroxyapatite Coatings with Antibacterial Nanometals, Obtained in the Electrophoretic Process on the Ti13Zr13Nb Alloy
PublikacjaThe risk of an early inflammation after implantation surgery of titanium implants has caused the development of different antimicrobial measures. The present research is aimed at characterizing the effects of nanosilver and nanocopper dispersed in the nanohydroxyapatite coatings, deposited on the Ti13Zr13Nb alloy, and on the chemical and biological properties of the coatings.The one-stage deposition process was performed by the...
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The Development of a Combined Method to Quickly Assess Ship Speed and Fuel Consumption at Different Powertrain Load and Sea Conditions
PublikacjaDecision support systems (DSS) recently have been increasingly in use during ships operation. They require realistic input data regarding different aspects of navigation. To address the optimal weather routing of a ship, which is one of the most promising field of DSS application, it is necessary to accurately predict an actually attainable speed of a ship and corresponding fuel consumption at given loading conditions and predicted...
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The Effectiveness of Basic Resuscitation Activities Carried out by Combat Paramedics of the Police, as Exemplified by Polish Counterterrorist Units
PublikacjaThe tasks carried out by Police officers are often accompanied by dangerous situations that threaten the life and health of the people involved, the police themselves, and bystanders. It concerns especially counter-terrorism police units whose activities are aimed at terrorists and particularly dangerous criminals, and their course is violent and aggressive. In conjunction with the inability to bring civilian rescue services into...
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The efficiency of turbomachinery in the zero-and three-dimensional approaches
PublikacjaEfficiency of turbomachinery is usually defined using an isentropic process. This approach provides a reliable reference point only when pressure and temperature measurements are available, e.g. at the casing inlet and outlet. In the case of a single stage internal efficiency determination the reference point is difficult. Computational fluid dynamics allows for an exact calculation of values of losses occurring in a turbine...
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The Influence of Drying Temperature on Color Change of Hornbeam and Maple Wood Used as Surface and Inner Layers of Wood Composites
PublikacjaThe thermal treatment of wood changes its structure due to the degradation of wood polymers (cellulose, hemicellulose and lignin), so the physical properties of wood are either improved or degraded. Color changes apply not only to natural wood, but also to such wood composites for which some amount of glue is used in their construction (e.g., plywood, blockboard or laminboard). This article is focused on the analysis of hornbeam...
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The Influence of Nanometals, Dispersed in the Electrophoretic Nanohydroxyapatite Coatings on the Ti13Zr13Nb Alloy, on Their Morphology and Mechanical Properties
PublikacjaIn this work, nanohydroxyapatite coatings with nanosilver and nanocopper have been fabricated and studied. The presented results concern coatings with a chemical composition that has never been proposed before. The present research aims to characterize the effects of nanosilver and nanocopper, dispersed in nanohydroxyapatite coatings and deposited on a new, non-toxic Ti13Zr13Nb alloy, on the physical and mechanical properties of...
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The influence of selected strain-based failure criteria on ship structure damage resulting from a collision with an offshore wind turbine monopile
PublikacjaOffshore wind farms are developing well all over the world, providing green energy from renewable sources. The evaluation of possible consequences of a collision involves Finite Element computer simulations. The goal of this paper was to analyse the influence of selected strain-based failure criteria on ship damage resulting from a collision with an offshore wind turbine monopile. The case of a collision between an offshore supply...
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The influence of the basic conditions of the forced feed of abrasive compound on the roughness of flat ceramic elements after lapping.
PublikacjaW docieraniu standardowym zawiesina ścierna dostarczana jest do strefy obróbki w sposób ciągły - zalewowo lub kroplowo, co generuje duże straty ścierniwa. W artykule opisano innowacyjny system dozowania i nanoszenia zawiesiny ściernej na powierzchnię żeliwnego docieraka tarczowego, który eliminuje tą wadę. W przeprowadzonych eksperymentach badano wpływ procentowej zawartości ziaren ściernych w nośniku oraz wielkość dawki zawiesiny...
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The influence of the grid density of measurement points on damage detection in an isotropic plate by the use of elastic waves and laser scanning Doppler vibrometry
PublikacjaDamage detection in structural components, especially in mechanical engineering, is an 2 important element of engineering practice. There are many methods of damage detection, in which 3 changes in various parameters caused by the presence of damage are analysed. Recently, methods 4 based on the analysis of changes in dynamic parameters of structures, i.e. frequencies or mode shapes 5 of natural vibrations, as well as changes in...
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The Influence of Tool Shape and Process Parameters on the Mechanical Properties of AW-3004 Aluminium Alloy Friction Stir Welded Joints
PublikacjaThe purpose of the following study was to compare the effect of the shape of a tool onthe joint and to obtain the values of Friction Stir Welding (FSW) parameters that provide the bestpossible joint quality. The material used was an aluminium alloy, EN AW-3004 (AlMn1Mg1). To theauthors’ best knowledge, no investigations of this alloy during FSW have been presented earlier. Fivebutt joints were made with a self-developed, cylindrical,...
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The Influence of Water and Mineral Oil on Pressure Losses in Hydraulic Motor
PublikacjaIn this paper, pressure losses in hydraulic motor supplied with water and mineral oil (two liquids that have significantly different viscosity and lubricating properties) are described and compared. The experimental tests were conducted using a hydraulic satellite motor that is dedicated to working with different liquids, including water. The methodology of measuring the pressure drop in internal channels of this motor is also...
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The Matter of Decision-Making Control Over Operation Processes of Marine Power Plant Systems with the Use of their Models in the form of Semi-Markov Decision-Making Processes
PublikacjaThe article presents the possibility to control the real operation process of an arbitrary device installed in the marine power plant based on the four-state semi-Markov process, being the model of the process, which describes the transition process of operational states of the device and the transition process of its technical states. All these states are precisely defined for the ship main engine (SG). A hypothesis is proposed...
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The non-invasive evaluation of heart function in patients with an acute myocardial infarction: The role of impedance cardiography
PublikacjaBackground: The purpose of this study was to analyze hemodynamic changes in patients treated with percutaneous coronary intervention (PCI) at an early stage of acute myocardial infarction (AMI) and at one-month follow-up. Methods: Patients with AMI (n = 27) who underwent PCI were analyzed using impedance cardiography (ICG). ICG data were collected continuously (beat by beat) during the whole PCI procedure and thereafter at every...
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The Physicochemical and Antibacterial Properties of Chitosan-Based Materials Modified with Phenolic Acids Irradiated by UVC Light
PublikacjaThis paper concerns the physicochemical properties of chitosan/phenolic acid thin films irradiated by ultraviolet radiation with wavelengths between 200 and 290 nm (UVC) light. We investigated the preparation and characterization of thin films based on chitosan (CTS) with tannic (TA), caffeic (CA) and ferulic acid (FA) addition as potential food‐packaging materials. Such materials were then exposed to the UVC light (254 nm) for...
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The Staged Combustion of Meat-and-Bone Meal:The Characteristics of Conversion Sub-processes and Large-Scale Process Outputs
Publikacjat Organic waste has been playing an increasingly important role in the energy market as those that may support the economies in pursuing towards decarbonization by increasing the share of renewables in the overall energy balance. In this group of alternative fuels, meat-and-bone meals being a post-production waste of the steadily developing meat industry, constitute a considerable proportion. Though they are rich in minerals, their...
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The use of thermal imaging camera to estimate velocity profiles based on temperature distribution in a free convection boundary layer
PublikacjaThis work describes an attempt to assess whether the temperature field from a thermal imaging camera can be converted into a velocity field with an accuracy sufficient for qualitative conducting or describing the phenomenon, i.e. when the Navier-Stokes, Fourier-Kirchhoff and continuity equations are mutually coupled. The consequence of this link between temperature fields and velocity is the possibility to formulate the hypothesis...
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Thermal and Hydrodynamic Phenomena in the Stagnation Zone — Impact of the Inlet Turbulence Characteristics on the Numerical Analyses
PublikacjaOne of the methods of heat transfer enhancement is utilization of the turbulent impinging jets, which were recently applied, for example, in the heat exchangers. Their positive impact on the heat transfer performance was proven, but many questions related to the origin of this impact are still unanswered. In general, the wall-jet interaction and the near-wall turbulence are supposed to be its main reason, but their accurate numerical...
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Thermal and technological aspects of double face grinding of C45 carbon steel
PublikacjaIn grinding, the contact zone temperature is a decisive factor influencing the achievable surface quality and the grinding tool wear. In contrast to other grinding processes, only few information regarding double face grinding with planetary kinematics when processing steel is known up to date. Since the successive substitution of in-dustrial double-sided lapping processes by double-sided grinding, it has become necessary to the...
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Thermal utilization of meat-and-bone meal using the rotary kiln pyrolyzer and the fluidized bed boiler – The performance of pilot-scale installation
PublikacjaThermal utilization of meat-and-bone meal (MBM) is subject to stringent regulations that are meant to provide elimination of any potential pathogens. Incineration as well as other possible routes for thermal conversion of MBM are still at the research state. The universal technology was developed that allows to combust various types of waste organic materials, including animal waste, municipal solid waste and sludge, mixed at any...
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Thermodynamic Analysis of Negative CO2 Emission Power Plant Using Aspen Plus, Aspen Hysys, and Ebsilon Software
PublikacjaAbstract: The article presents results of thermodynamic analysis using a zero-dimensional mathematical models of a negative CO2 emission power plant. The developed cycle of a negative CO2 emission power plant allows the production of electricity using gasified sewage sludge as a main fuel. The negative emission can be achieved by the use this type of fuel which is already a “zeroemissive” energy source. Together with carbon capture...
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Thermo-Mechanical Simulation of Underwater Friction Stir Welding of Low Carbon Steel
PublikacjaThis article investigates the flow of materials and weld formation during underwater friction stir welding (UFSW) of low carbon steel. A thermo-mechanical model is used to understand the relation between frictional heat phenomena during the welding and weld properties. To better understand the effects of the water environment, the simulation and experimental results were compared with the sample prepared by the traditional friction...
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Three-dimensional modeling and automatic analysis of the human nasal cavity and paranasal sinuses using the computational fluid dynamics method
PublikacjaPurpose The goal of this study was to develop a complete workflow allowing for conducting computational fluid dynam- ics (CFD) simulation of airflow through the upper airways based on computed tomography (CT) and cone-beam computed tomography (CBCT) studies of individual adult patients. Methods This study is based on CT images of 16 patients. Image processing and model generation of the human nasal cavity and paranasal sinuses...
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Torque capacity of multidisc wet clutch with reference to friction occurrence on its spline connections
PublikacjaIn this article developed mathematical model that includes friction occurrence on spline connections is presented. The work also contains results of experimental research on torque capacity of multidisc wet clutch. These results are expressed as a function of contact pressure for different number of friction surfaces. Due to increased interest in research concerning multidisc wet clutches it is essential to determine impact of...
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Torque Transmitted by Multi-plate Wet Clutches in Relation to Number of Friction Plates and Their Dimensions
PublikacjaIn the paper results of experimental tests on multi-plate wet clutch torque capacity for various diameters and numbers of friction plates are presented. Construction of an apparatus for laboratory tests of wet clutch engagement, drag torque and maximum torque is shown. Methodology of maximum torque capacity experiment and hydraulic circuit diagram, which supplies a motor and an actuator for the experiment are described. Analytically...
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Trends shaping innovations in the aerosol market
PublikacjaNew hygiene regimes and sustainability commitments are helping to shape the aerosol market. Norbert Piotrowski of Aerosol Service Poland explains the thinking behind the company’s latest hygiene innovations.
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Turning maneuver as a potential cause of the next stability failure mode for a ship in operation
PublikacjaThe only formal stability-related requirement referring to a turning maneuver of a ship results from the IS Codeand its application is limited to passenger ships only. The goal of the adopted criterion is to prevent an excessiveangle of heel in turn. Likewise, the remaining prescriptive criteria, this one is simply based on the concept ofa threshold that must not be exceeded. In this case, the angle of heel...
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Ultimate compressive strength assessment of uncleaned and cleaned corroded plates with locked crack
PublikacjaThe work presented here investigates the structural response of cleaned corroded plates, subjected to compressive load in the presence of a locked crack, where the change of mechanical properties as a result of corrosion development and the cleaning process is also accounted for. A Finite Element model for assessing the compressive strength, considering geometric and material nonlinearities, is developed, and the analysed plates...
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Volumetric and torque efficiency of pumps during start-up in low ambient temperatures
PublikacjaThe volumetric, torque and total efficiency of hydraulic pumps change during start-up in low ambient temperatures, as well as in thermal shock conditions, un-til they reach the set conditions. The time to reach steady-state conditions de-pends on many parameters: ambient temperature, flow rate, fluid temperature, design of hydraulic units. The author carried out tests of hydraulic pumps in the Hydraulics Laboratory of the Faculty...
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Water-lubricated stern tube bearing - experimental and theoretical investigations of thermal effects
PublikacjaThe paper presents research results of thermal phenomena accompanying operation of a water-lubricated stern tube bearing with axial grooves. Experimental tests revealed, that intensity of forced axial flow has strong influence on bush temperature. Numerical simulations focused on investigation of the thermal phenomena under operation of water-lubricated journal bearing showed, that restricted axial flow promotes backflow of the...
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W-dominance: Tradeoff-inspired dominance relation for preference-based evolutionary multi-objective optimization
PublikacjaThe paper presents a method of incorporating decision maker preferences into multi-objective meta-heuristics. It is based on tradeoffcoefficients and extends their applicability from bi-objective to multi-objective. The method assumes that a decision maker specifies a priori each objective’s importance as a weight interval. Based on this, w-dominance relation is introduced, which extends Pareto dominance. By replacing reference...
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Weldability of Underwater Wet-Welded HSLA Steel: Effects of Electrode Hydrophobic Coatings
PublikacjaThe paper presents the effects of waterproof coatings use to cover electrodes on the weldability of high-strength, low-alloy (HSLA) steel in water. With the aim of improving the weldability of S460N HSLA steel in water, modifications of welding filler material were chosen. The surfaces of electrodes were covered by different hydrophobic substances. The aim of the controlled thermal severity (CTS) test was to check the influence...
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Wood Moisture-Content Measurement Accuracy of Impregnated and Nonimpregnated Wood
PublikacjaThe influence of the impregnation process of pine wood (Pinus sylvestris L.) samples on the electrical resistance changes and the moisture-content measurement accuracy is presented in this paper. In this study, the resistances of impregnated and nonimpregnated green pine timber harvested from northern Poland were compared. An impregnation method based on a vacuum-pressure chamber was used. Copper salts were applied as the impregnated...
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Worm Gear Drives with Improved Kinematic Accuracy
PublikacjaThis paper presents the fundamentals of the design and applications of new worm gear drive solutions, which enable the minimisation of backlash and are characterised by higher kinematic accuracy. Different types of worm surfaces are briefly outlined. Technological problems concerning the principles of achieving a high degree of precision in machining are also described. Special attention is paid to the shaping of conical helical...
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Wpływ parametrów zewnętrznych na wytwarzanie pary w kotle opalanym
PublikacjaW artykule przedstawiono analizę statystyczną wpływu parametrów zewnętrznych na strumień ciepła zawartego w paliwie dolotowym do okrętowego kotła opalanego. Jako parametry niezależne wytypowano średnią dobową moc chwilową silnika głównego i agregatów prądotwórczych, temperaturę wody zaburtowej oraz zanurzenie. Analizę przeprowadzono dla czterech różnych stanów eksploatacyjnych badanego statku.
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Wpływ sposobu suszenia na wiązkość i naprężenia tnące przy przecinaniu wybranych gatunków drewna
PublikacjaW rozprawie doktorskiej przedstawiono wpływ sposobów suszenia na wiązkość i naprężenia tnące w strefie skrawania, które zgodnie ze współczesną mechaniką pękania można uznać za energetyczne wskaźniki skrawalności. Badania zostały przeprowadzone dla próbek z drewna sosnowego (Pinus sylvestris L.) i bukowego (Fagus silvatica L.) suszonego czterema sposobami. Trzy z nich, to najczęściej wykorzystywane w przemyśle, suszenie w sposób...
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Wpływ właściwości czynnika roboczego na eksploatację wybranych systemów chłodniczych
PublikacjaW artykule przedstawiono wpływ wyboru czynnika roboczego na eksploatację teoretycznego systemu chłodniczego. Niniejszą analizę przeprowadzono dla trzech układów chłodniczych, które na potrzeby prowadzonej analizy sklasyfikowano jako: grupa domowa, grupa przemysłowa i grupa specjalna. Przyjętymi urządzeniami są: w grupie domowej – klimatyzator typu powietrze-powietrze, w grupie przemysłowej – chłodnia statku do transportu żywności...
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Wpływ zmiany parametrów geometrycznych na wydajność i efektywność protezy zastawki aortalnej Human Aortic Bioprosthesis
PublikacjaW pracy wykazano na podstawie rezultatów badań in vitro, że konstrukcja wykonana z nanocelulozy bakteryjnej, posiada wszelkie cechy protezy zastawki aortalnej możliwe do wykazania na drodze ww. badań oraz że określone cechy geometrii protezy wpływają na jej efektywność i funkcjonalność. W szczególności, w pracy przedstawiono wyniki badań in vitro trzech modeli konstrukcji protezy zastawki aortalnej, oznaczonych M2, M4’ i M4. Badania...
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Z działalności polonijnych stowarzyszeń inżynierów i techników
PublikacjaPrzedstawiono pokrótce historię i działalność wybranych polonijnych stowarzyszeń inżynierów i techników w Europie i Ameryce. Szczegółowiej omówiono historię i dokonania Stowarzyszenia Techników Polskich w Wielkiej Brytanii, które w roku 2020 obchodziło 80-lecie działalności.
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Z historii polonijnych stowarzyszeń inżynierów i techników
PublikacjaPrzedstawiono ogólną charakterystykę wybranych polonijnych stowarzyszeń inżynierów i techników działających w Europie i Ameryce. Podano motywy ustanowienia międzynarodowego dnia inżyniera, obchodzonego corocznie 4 marca, począwszy od roku 2020.