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Experimental ultimate strength assessment of stiffened plates subjected to marine immersed corrosion
PublikacjaThis study experimentally analyses the impact of marine immersed corrosion degradation on the compressive strength of the stiffened plates where the lower degradation levels were considered. The corrosion degradation test was accelerated by controlling the natural corrosion environmental factors, avoiding applying an electric current. Different groups of corrosion degradation levels and initial plate thicknesses were investigated....
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Event-Triggered Communication in Cooperative, Adaptive Model Predictive Control of a Nuclear Power Plant’s Turbo–Generator Set
PublikacjaThis paper discusses the issue of optimizing the communication between the components of a cooperating control system formed by a pair of MPC controllers of a nuclear power plant turbine set using online recursive least squares identification. It is proposed to use event-triggered communication, i.e., sending information only at selected time instants, as opposed to the standard approach where communication is triggered by time...
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Preliminary experimental research on stability of truss' joint with positive eccentricity
PublikacjaRecently, a very large interest in lightweight steel structures made from cold-formed sections has been noticeable. In the design practice, a large emphasis is put on rational shaping of both the thin-walled elements and constructions designed on them. The aim of this paper is to present the methodology for preparation of experimental research that model the behaviour of members in trusses made of cold-formed sections with positive...
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The Effectiveness of Polymer Damper in Damage Reduction of Temporary Steel Grandstand
PublikacjaA large number of accidents involving damage of temporary grandstands during different types of events were observed in the past. The aim of the paper is to analyse numerically the effectiveness of a polymer damper in damage reduction of a temporary steel scaffolding grandstand exposed to dynamic load due to jumping. The element has been installed as a diagonal one at the back part of the structure. The method has been compared...
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Wear in reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). No lubrication (DRY). Specim. set K01
Dane BadawczeFriction and wear tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: DRY. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test rig: TPZ-1 Tribometer.Running time: progressive increments of 10, 15, 30, 60, 180 and 300s. (stored in separate folders).Specimen...
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Wear in reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). Lubricant - PARAFFIN OIL. Specim. set K09 - full run
Dane BadawczeFriction and wear tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: PARAFFIN OIL. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test rig: TPZ-1 Tribometer.Running time: progressive increments of 10, 15, 30, 60, 180 and 300s. (stored in separate...
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Wear in reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). Lubricant - DISTILLED WATER. Specim. set K06
Dane BadawczeFriction and wear tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: DISTILLED WATER. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test rig: TPZ-1 Tribometer.Running time: progressive increments of 10, 15, 30, 60, 180 and 300s. (stored in separate...
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Wear in reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). No lubrication (DRY). Specim. set K04
Dane BadawczeFriction and wear tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: DRY. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test rig: TPZ-1 Tribometer.Running time: progressive increments of 10, 15, 30, 60, 180 and 300s. (stored in separate folders).Specimen...
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Wear in reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). Lubricant - PARAFFIN OIL. Specim. set K09 - pre-run (10s)
Dane BadawczeFriction and wear tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: PARAFFIN OIL. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test rig: TPZ-1 Tribometer.Running time: progressive increments of 10, 15, 30, 60, 180 and 300s. (stored in separate...
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Wear in reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). Lubricant - PARAFFIN OIL. Specim. set K08
Dane BadawczeFriction and wear tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: PARAFFIN OIL. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test rig: TPZ-1 Tribometer.Running time: progressive increments of 10, 15, 30, 60, 180 and 300s. (stored in separate...
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Wear in reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). Lubricant - DISTILLED WATER. Specim. set K07
Dane BadawczeFriction and wear tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: DISTILLED WATER. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test rig: TPZ-1 Tribometer.Running time: progressive increments of 10, 15, 30, 60, 180 and 300s. (stored in separate...
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Wear in reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). No lubrication (DRY). Specim. set K05
Dane BadawczeFriction and wear tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: DRY. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test rig: TPZ-1 Tribometer.Running time: progressive increments of 10, 15, 30, 60, 180 and 300s. (stored in separate folders).Specimen...
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Wear in reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). Lubricant - DISTILLED WATER. Specim. set K02
Dane BadawczeFriction and wear tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: DISTILLED WATER. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test rig: TPZ-1 Tribometer.Running time: progressive increments of 10, 15, 30, 60, 180 and 300s. (stored in separate...
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Wear in reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). No lubrication (DRY). Specim. set K03
Dane BadawczeFriction and wear tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: DRY. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test rig: TPZ-1 Tribometer.Running time: progressive increments of 10, 15, 30, 60, 180 and 300s. (stored in separate folders).Specimen...
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Complex multidisciplinary optimization of turbine blading systems
PublikacjaThe paper describes the methods and results of direct optimization of turbine blading systems using a software package Opti_turb. The final shape of the blading is obtained from minimizing the objective function, which is the total energy loss of the stage, including the leaving energy. The current values of the objective function are found from 3D RANS computations (from a code FlowER) of geometries changed during the process...
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DEFORMATIONS OF INNOVATIVE COLD-FORMED GEB SECTIONS
PublikacjaPermanent urban growth of the world of today world implies demanding challenges for the steel construction industry. Nowadays, one of the most important issues is the cost optimization of steel structures. Since the weight of building materials is a major component of the total cost, engineers and designers try to reduce structural weight, without compromising durability and sustainability of a steel structure. Therefore, light...
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Nitrogen removal via the nitrite pathway during wastewater co-treatment with ammonia-rich landfill leachates in a sequencing batch reactor
PublikacjaThe biological treatment of ammonia-rich landfill leachates due to an inadequate C to N ratio requires expensive supplementation of carbon from an external carbon source. In an effort to reduce treatment costs, the objective of the study was to determine the feasibility of nitrogen removal via the nitrite pathway during landfill leachate co-treatment with municipal wastewater. Initially, the laboratory-scale sequencing batch reactor...
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A Multi Rig Screening Test for Thin Ceramic Coatings in Bio - Tribological Applications
PublikacjaA method is presented for the comparative testing of wear resistance of ceramic coatings made from materials potentially feasible in tribo - medical applications, mainly orthopaedic implants made from ceramics coated metals for low cost, long life and low wear particle emission into the body. The method was devised as the main tool for use in research and is comprised of flat on flat and ball on flat surface (sliding) tests. Seven...
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Influence of bush wear in water lubricated marine stern tube bearings with shaft misalignment
PublikacjaWater lubricated propeller shaft bearings are frequently employed on modern ships due to their advantages such as durability, simplicity and low price. Specific working conditions on ships cause shaft misalignment which often results in rapid wearing of bush and shaft. Shaft misalignment could be an effect of manufacturing or assembly faults but sometimes it appears due to hull or shaft deformation. The wearing process has influence...
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Influence of Actual Curing Conditions on Mechanical Properties of Concrete in Bridge Superstructures
PublikacjaThis article presents the research on the mechanical characteristics of concrete in the construction of three concrete bridges. A system of recording the internal temperature of concrete and automatic control of laboratory ovens was used for specimen curing. This allowed the specimens to be cured under conditions similar to those occurring in the structure. Before the construction, reference blocks were used to define similar curing...
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Investigations on fracture in reinforced concrete beams in 3-point bending using continuous micro-CT scanning
PublikacjaThis study explores a fracture process in rectangular reinforced concrete (RC) beams subjected to quasi-static three-point bending. RC beams were short and long with included longitudinal reinforcement in the form of a steel or basalt bar. The ratio of the shear span to the effective depth was 1.5 and 0.75. The focus was on the load–deflection diagram and crack formation. Three-dimensional (3D) analyses of the size and distribution...
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Die neue Straßenbrücke in Toruń (Thorn) – Teil 2 – Nachweise
PublikacjaAls Fortsetzung von Teil 1, der über den Entwurf und den Bau der neuen, die Weichsel querenden Straßenbrücken in Toruń (deutsch: Thorn) berichtet, geht es im Folgenden um die theoretischen und experimentalen Nachweisen zum Montageprozess und zu Probebelastungen. Somit eine umfassende Beurteilung der beschriebenen , herausragenden Ingenieursleistung gegeben.
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Zwodzona kładka dla pieszych na wyspę Ołowiankę w Gdańsku - analizy dynamiczne z wykorzystaniem modelu numerycznego MES
PublikacjaW artykule przedstawiono projekt zwodzonej kładki dla pieszych przez rzekę Motławę na wyspę Ołowiankę w Gdańsku. Omówiono jej konstrukcję oraz obliczenia numeryczne sprawdzające wytrzymałość, ugięcie i siły w siłownikach podczas zwodzenia. Dokonano również oceny poziomu komfortu i nośności konstrukcji pod wpływem działania obciążeń dynamicznych generowanych przez pieszych.
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Prognozowanie wpływu drgań komunikacyjnych na budynki mieszkalne za pomocą sztucznych sieci neuronowych i maszyn wektorów wspierających
PublikacjaDrgania komunikacyjne mogą stanowić duże obciążenie eksploatacyjne budynku, powodując zarysowania i spękania tynków, odpadanie wypraw, zarysowania konstrukcji, pękanie elementów konstrukcji lub nawet zawalenie się budynku. Pomiary drgań na rzeczywistych konstrukcjach są pracochłonne i kosztowne, a co ważne nie w każdym przypadku są one uzasadnione. Celem pracy jest analiza autorskiego algorytmu, dzięki któremu z dużym prawdopodobieństwem...
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Konzepte zur Energieeffizienzsteigerung bei Internet-Zugangsgeräten
PublikacjaThe key issue of this paper is the power management of Internet access devices. The paper commences with an outline on the energy consumption of today's IT devices. It is followed by a description of options to increase energy efficiency of computers. The paper proves that in practice network cards and other IT network components, such as modems, network access points, switches and routers have the maximum energy consumption -...
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Kinetic analysis of the stage for a high speed steam turbine
PublikacjaThis article analyzes possibilites of resonances within a control stage for a high speed steam turbine. This stage hase been based on assembling of a single blade to a rotating disk and increasing of rigidity of the system by using of a bandage. In the analysis will be nd a possiblity of resonance frequency, and mistuning by showing safety working ranges. The calculations have bean used the3D modal and harmonic analysis by the...
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Network-assisted processing of advanced IoT applications: challenges and proof-of-concept application
PublikacjaRecent advances in the area of the Internet of Things shows that devices are usually resource-constrained. To enable advanced applications on these devices, it is necessary to enhance their performance by leveraging external computing resources available in the network. This work presents a study of computational platforms to increase the performance of these devices based on the Mobile Cloud Computing (MCC) paradigm. The main...
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Numerical simulations of novel GFRP sandwich footbridge
PublikacjaIn the following paper some aspects of numerical analysis and designing stages of a footbridge made of composite materials are elucidated. Because of the used materials the design process in this case is not ordinary and requires the development of concepts, material selections, identification of material properties, numerical simulations, strength calculations, serviceability and durability analyses. This contribution presents...
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Experimental dynamic study on a timber-frame house using shaking table
PublikacjaThe aim of this paper is to show the results of the shaking table experimental study concerning the behaviour of the model of the timber-frame house under earthquake excitation and impact loading. In order to determine the basic dynamic properties of the undamaged structure, the free vibration and the sweep-sine tests were first conducted. Then, the model was excited using the time history record of the El Centro earthquake of...
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Structural design and sensitivity analysis of semi-rigid pavement of a motorway
PublikacjaThis paper presents application of mechanistic-empirical methods in design of semi-rigid pavement for a section of a motorway in Poland. The stage construction was assumed. Three fatigue criteria were applied in the design. For asphalt fatigue cracking and subgrade soil the criteria from the Asphalt Institute (USA) were applied. For fatigue cracking of cement stabilized bases the Dempsey (USA) and De Beer (South Africa) criteria...
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Influence of Wastewater Treatment Technology on Particle Size Distribution in the Effluent
PublikacjaSuspended solids in water and wastewater usually carry quite a large load of pollutants (organic substances, nutrients, heavy metals, etc.) adsorbed on the particles surface. Particles of different sizes carry different types and quantities of pollutants. Therefore, particle size distribution is of importance in waster and wastewater treatment. In the article the influence of different treatment technologies on particle size distribution...
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A multi-agent method for periodicity detection in distributed events
PublikacjaMulti-agent systems working in constantly changing environments may be challenged by instantaneous unavailability of their autonomous agents caused e.g. by limited computing resources. A new method of self-organization of distributed service components is proposed, suitable for multi-agent systems. This method relies on particular agents carrying out separate analyzes of their individual processing loads or other specific events....
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Airstrip Ground Improvement Works by Blasting Charge Technique and Dredged-Ash Material Mixture
PublikacjaSoil improvement by blasting charge technique is known in geotechnics as one of the efficient and inexpensive method. It can be used in preparing of underground to found road construction and buildings as well. The technique proves usefulness especially when dynamic load is applied. It is because of non-stiff or rather resilient type soil after improvement. In noncohesive or organic soil, blasting charge...
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Experimental research on marine oil-lubricated stern tube bearing
PublikacjaBearings of propeller shafts are very crucial elements of the propulsion system of each of the ships. The safety of shipping depends on their durability and reliability. The new legal restrictions mean that today we are looking for environmentally friendly solutions. That is why water-lubricated bearings are becoming more and more popular. So, will oil-lubricated shaft bearings belong to the past? The bearing with a white metal...
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Constant vs. Variable Efficiency of Electric Drive in Train Run Simulations
PublikacjaTrain run simulations, which focus on various power- and energy-oriented aspects, should reflect the losses in the electric powertrain. In general, the powertrain efficiency varies with respect to load and speed. Including this relation in simulation requires knowledge about detailed drivetrain parameters, which are often unavailable. This paper verifies the possibility to approximate the drivetrain efficiency in train run simulations...
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Sulfate‐reducing bacteria‐assisted hydrogen‐induced stress cracking of 2205 duplex stainless steels
PublikacjaThe paper presents the results of a laboratory investigation of the microbiologically assisted hydrogen‐induced stress cracking (HISC) of 2,205 duplex stainless steel (DSS). The testing of susceptibility toward HISC was performed with two different methods. Precharged in sulfate‐reducing bacteria (SRB), inoculated medium samples were subjected to slow strain‐rate testing in artificial seawater. In situ constant load tests were...
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Non-Destructive Testing of a Sport Tribune under Synchronized Crowd-Induced Excitation Using Vibration Analysis
PublikacjaThis paper presents the concept of repairing the stand of a motorbike speedway stadium. The synchronized dancing of fans cheering during a meeting brought the stand into excessive resonance. The main goal of this research was to propose a method for the structural tuning of stadium stands. Non-destructive testing by vibration methods was conducted on a selected stand segment, the structure of which recurred on the remaining stadium...
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Structural response of existing spatial truss roof construction based on Cosserat rod theory
PublikacjaPaper presents the application of the Cosserat rod theory and newly developed associated finite elements code as the tools that support in the expert-designing engineering practice. Mechanical principles of the 3D spatially curved rods, dynamics (statics) laws, principle of virtual work are discussed. Corresponding FEM approach with interpolation and accumulation techniques of state variables are shown that enable the formulation...
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Restricted open shop scheduling
PublikacjaIn the real applications the open shop scheduling models often require some additional constraints and adequate models. We concern the restrictions in the open shop scheduling related to an instance of the problem and to a feasible solution. Precisely, we require that each jobs consists of the bounded number of operations and each machine has a bounded load (i.e., the total number of operations executed on this machine in a schedule)....
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Numerical analysis of a temporary steel grandstand
PublikacjaThe purpose of this paper is to present the results of the numerical analysis focused on the response of the temporary steel scaffolding grandstand subjected to human-induced vibrations due to jumping. Shell as well as beam elements have been used in the numerical model. Its first stage has involved conducting modal analysis in order to determine the modes of free vibrations and the corresponding natural frequencies for the empty...
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Design of a test bench for determining the general characteristics of an internal combustion engine using a hydraulic power take-off system
PublikacjaThe paper presents a design of an engine test bench, which is used to determine the general characteristics of a truck engine using a power take-off (PTO). PTO drives a hydraulic system that generates a load on the engine at various points in its operation in the power range specified by the hydraulic system. The design allows for stationary and mobile tests with the test bench mounted on the truck, without any modification of...
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Strategies for achieving energy neutrality in biological nutrient removal systems - a case study of the Slupsk WWTP (northern Poland)
PublikacjaThe paper presents a model-based evaluation of technological upgrades on the energy and cost balance in a large biological nutrient removal wastewater treatment plant (WWTP) in the city of Slupsk (northern Poland). The proposed upgrades include chemically enhanced primary sludge removal and reduction of the nitrogen load in the deammonification process employed for reject water treatment. Simulations enabled to estimate the increased...
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Composite GFRP U-shaped footbridge
PublikacjaThe paper presents proposals for the use of glass fiber reinforced polymer composites for the construction of engineering objects, known and commonly used in the shipbuilding industry. An example of a pedestrian footbridge was used in this case, which, despite the considerable thickness of the structural material, was made using infusion technology in one production cycle. The designed and produced footbridge span is durable, dynamically...
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RESEARCH ON HYDRODYNAMIC PEEK JOURNAL BEARINGS LUBRICATED WITH WATER AND OIL
PublikacjaThe main purpose of the research was to determine the possibilities and experimentally test the benefits of replacing conventional oil lubrication with ecological water lubrication. Tests were carried out on a test rig for hydrodynamic radial bearings under conditions representative of the expected applications for the bearing in water turbines. Bearings made from the polymer material PEEK (polyether ether ketone) were tested under static...
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Differential Quadrature Method for Dynamic Buckling of Graphene Sheet Coupled by a Viscoelastic Medium Using Neperian Frequency Based on Nonlocal Elasticity Theory
PublikacjaIn the present study, the dynamic buckling of the graphene sheet coupled by a viscoelastic matrix was studied. In light of the simplicity of Eringen's non-local continuum theory to considering the nanoscale influences, this theory was employed. Equations of motion and boundary conditions were obtained using Mindlin plate theory by taking nonlinear strains of von Kármán and Hamilton's principle into account. On the other hand, a...
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LNG TANK IN ŚWINOUJŚCIE: NONLINEAR ANALYSIS OF THE TANK DOME ELEMENTS BEHAVIOUR
PublikacjaIn this paper, the dome of a tank in the Świnoujście LNG terminal is analysed. Some of the rafter ribs at the connection with hangers were not mounted during construction of the tank dome. Therefore, it has become necessary to estimate its response, which has been done with the aid of some computational models of the dome, that have been created in the finite element method environment. Different local models are studied, aiming...
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Examination of selected failure criteria with asymmetric shear stresses in the collapse analysis of laminated shells
PublikacjaThe paper is concerned with failure analysis of composite shells performed with the usage of the nonlinear 6‐parameter shell theory with drilling rotation degree of freedom. This special theory embodies naturally unlim-ited translations and rotations and is suitable for analysis of irregular shells for instance with various, partic-ularly orthogonal, intersections. The presence of the drilling rotation is inherently accompanied...
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EXPERIMENTAL EVALUATION OF DLC/STEEL SLIDING CONTACTS’ OPERATIONAL ENVELOPE
PublikacjaIn an industrial project concerning sliding bearings, a sliding pair was selected of high alloy steel vs. industrial grade DLC coated high alloy steel as a basis for an innovative design of high performance sliding bearings lubricated with a synthetic oil for use in geared transmission units. The development process required credible data on the ultimate resistance of the sliding pair to very high contact stress. An experimental...
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Strategies for Achieving Energy Neutrality in Biological Nutrient Removal Systems – a Case Study of the Slupsk WWTP (northern Poland)
PublikacjaThe paper presents a model-based evaluation of technological upgrades on the energy and cost balance in a large biological nutrient removal wastewater treatment plant (WWTP) in the city of Slupsk (northern Poland). The proposed upgrades include chemically enhanced primary sludge removal and reduction of the nitrogen load in the deammonification process employed for reject water treatment. Simulations enabled to estimate the increased...
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The determinants of morphology and properties of the nanohydroxyapatite coating deposited on the Ti13Zr13Nb alloy by electrophoretic techniqe
PublikacjaThe titanium and its alloys belong at present to the most preferred and commonly applied biomaterials for load- bearing implants. The surfaces of biomaterials are subjected to modification, including the hydroxyapatite coatings deposited in order to ensure corrosion resistance and better joining between an implant and a bone through the possibility of ingrowth bone into the coating. In this paper, the morphology and properties...