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Search results for: ELASTIC PIPE
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Numerical Modelling of Connections Between Stones in Foundations of Historical Buildings
PublicationThe aim of this paper is to analyse the behaviour of old building foundations composed of stones (the main load-bearing elements) and mortar, based on numerical analysis. Some basic aspects of historical foundations are briefly discussed, with an emphasis on their development, techniques, and material. The behaviour of a foundation subjected to the loads transmitted from the upper parts of the structure is described...
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Separation of the effects of notch and macro residual stress on the MFL signal characteristics
PublicationMagnetic flux leakage (MFL) distribution for three configurations of samples has been investigated in order to study the influence of notch and plastic deformation separately as well as together. Samples have been made of S355 steel. The MFL signal measurements were carried out along the longest dimension of the sample over a length of 120 mm. Two components of magnetic field were measured: 1) tangential to the main axis and 2)...
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Fracture in Asymmetric Bonded Joints
PublicationAdhesion was studied in asymmetric bonded joints using fracture mechanics tests. The asymmetric bonded joints consist of two different type and/or thickness materials bonded by an adhesive. Mentions of asymmetric bonded joint tests employed so far are rare in the literature. They are imperfect and therefore are not standardized. Accordingly three new tests were introduced in this work to study bonded joints. The new metrological...
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Study of the influence of thermal factors on the welding process of polyethylene gas pipelines,
PublicationA one-dimensional calculation scheme is proposed with the help of which it is possible to determine and set the technological parameters with the accuracy to be realized in production conditions: the temperature of the heating element and the heating time, which allows maximum mechanization of the technological operations of polyethylene gas pipelines welding. The numerical value of the coefficient of temperature for polyethylene...
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Installation of CMC columns in overconsolidated clays
PublicationDuring rigid inclusions execution in the subsoil some monitoring data are registered by a drilling rig for quality control. The use of these data can improve the design procedure of soil improvement as they can provide some information about the position of bearing strata and the energy necessary to install the column in the ground. In this paper the parameters registered in a drilling machine are described, the installation...
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Przetwarzanie i wnioskowanie z wiedzy o różnym poziomie zaufania
PublicationOntologie i bazy wiedzy wykorzystuje się w wielu zastosowaniach, takŜe takich, w których wnioskowanie ma charakter krytyczny, jak np. w przypadku systemów medycznych. W rozdziale przedstawione zostały kwestie zaufania do danych przechowywanych w bazach wiedzy i pobieranych z zewnętrznych źródeł. Opisane zostały przykłady uwzględnienia aspektów zaufania wykorzystujące kartograficzną reprezentację wiedzy - nowe podejście opracowane...
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Revisiting The Determination Of Cutting Power While Sawing Of Wood With Circular Saw Blades By Means Of Fracture Mechanics
PublicationIn the classical approach, energetic effects (cutting forces and cutting power) of wood sawing process are generally calculated on the basis of the specific cutting resistance, which is in the case of wood cutting the function of more or less important factors. On the other hand, cutting forces (power) could be considered from a point of view of modern fracture mechanics. Cutting forces may be employed to determine not only toughness...
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Jakub Konkol dr inż.
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Acoustical images of the Gulf of Gdansk
PublicationAcoustic images of seabed are of interest to specialists in the field of marine engineering, marine navigation, marine archeology, hydrogeology, etc. New technolo gies based on use of elastic waves, predominantly acoustic waves that allow detecting complexity of geometric forms of seabed, ensure progress in studying the bathymetric structure of seafloor. Use of parametric sources of waves generated...
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Geometrically nonlinear FEM analysis of FGM shells based on neutral physical surface approach in 6-parameter shell theory
PublicationThe paper presents the formulation of the elastic constitutive law for functionally graded materials (FGM) on the grounds of nonlinear 6-parameter shell theory with the 6th parameter being the drilling degree of freedom. The material law is derived by through-the-thickness integration of the Cosserat plane stress equations. The constitutive equations are formulated with respect to the neutral physical surface. The influence of...
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ANALYSIS OF BRACE STIFFNESS INFLUENCE ON STABILITY OF THE TRUSS
PublicationThe paper is devoted to the numerical and experimental research of stability of a truss with side elastic supports at the top chord. The structure is a model of a real roof truss scaled by factor ¼. The linear buckling analysis and non-linear static analysis were carried out. The buckling length factor for the compressed top chord was calculated and the limit load for the imperfect truss shell model with respect to brace stiffness...
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Mechanical properties of mosquito nets in the context of hernia repair
PublicationThe paper deals with issue of applying mosquito nets as implants in hernia repair, which have already been used in resource-poor developing countries. Uniaxial tensile tests have been conducted on polyester mosquito meshes in two orthogonal directions. Non-linear elastic constitutive laws parameters have been identified to be applied in dense net material models. Mechanical performance of tested mosquito nets has been compared...
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Dipole-driven dynamics for near-threshold electron/positron interactions with pyrimidinic DNA bases: a path to compound formations
PublicationCalculations are reported for electron and positron scattering from isolated cytosine and thymine, where the two pyrimidinic single-ring DNA bases, in the gas-phase at energies near the elastic threshold, they reveal the special features of the dipole-driven scattering states. All molecules examined exhibit, in fact, supercritical (>1.67 D) permanent dipoles which can therefore also support, below threshold, excited bound compound...
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A two dimensional approach for modelling of pennate muscle behaviour
PublicationThe purpose of this study was to elaborate a two-dimensional approach for unipennate and bipennate striated skeletal muscle modelling. Behavior of chosen flat pennate muscle is modelled as a rheological system composed of serially linked passive and active fragments having different mechanical properties. Each fragment is composed of three elements: mass element, elastic element and viscous element. Each active fragment furthermore...
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Assessment of Wooden Beams from Historical Buildings Using Ultrasonic Transmission Tomography
PublicationThe main goal of this study was non-destructive evaluation of wooden elements using ultrasonic waves. The inspection was carried out on wooden beams from a historical object. Elastic wave signals were processed by ultrasonic transmission tomography to obtain imaging of the internal structure of tested elements without disturbing their state and integrity. The focus was on the influence of wood anisotropy on the propagation of ultrasonic...
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Identification of Shear Modulus Parameters of Half-space Inhomogeneous by Depth
PublicationThe paper propose a method for determining of the parameters of the exponential shear modulus of a functionally graded half-space based on the solution of the problem of a pure shear of an elastic functionally graded half-space by a strip punch. The solution of the integral equation of the contact problem is constructed by asymptotic methods with respect to the dimensionless parameter. The dependence of contact stresses on the...
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Perspektywy rozwoju w Europie systemów sanitarnych z zastosowaniem toalet separujących
PublicationIstniejące technologie z tradycyjnymi toaletami zbiorczymi (WC), kanalizacją ogólnospławną (względnie rozdzielczą) oraz oczyszczalnią centralną niosą za sobą szereg wad i nie rozwiązują problemu gospodarki wodno-ściekowej. Ochrona wód bazuje nadal na filozofii "end-of-pipe" i oczyszczalniach komunalnych. Pomimo wysokiej efektywności oczyszczania ścieków, z obiegu przyrodniczego zostają po drodze usunięte wysoko wartościowe substancje...
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Experimental and Computational Fluid Dynamics Studies on Straight and U-Bend Double Tube Heat Exchangers with Active and Passive Enhancement Methods
PublicationIn this work, the authors wanted to demonstrate the possibility to increase the heat transfer efficiency by using simple wire coil inserts to create turbulent flow in the boundary layer as well as air blowing into the annulus of the pipe. Experimental investigations were carried out for four heat exchanger constructions, i.e., plain double tube, turbulized double tube, plain U-bend double tube, U-tube with turbulator, plain double...
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3D printed ABS thermoplastic vs. steel. Dry sliding wear test in constant load & velocity ring on flat configuration. Test parameters: print layer thickness and orientation. Test symbol: 009_v_2
Open Research DataData gathered in sliding ring-on-block (flat contact) tribological experiment. Materials: alloy steel (heat treated) vs. ABS plastic.
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3D printed ABS thermoplastic vs. steel. Dry sliding wear test in constant load & velocity ring on flat configuration. Test parameters: print layer thickness and orientation. Test symbol: 009_v_3
Open Research DataData gathered in sliding ring-on-block (flat contact) tribological experiment. Materials: alloy steel (heat treated) vs. ABS plastic.
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3D printed ABS thermoplastic vs. steel. Dry sliding wear test in constant load & velocity ring on flat configuration. Test parameters: print layer thickness and orientation. Test symbol: 009_h_3
Open Research DataData gathered in sliding ring-on-block (flat contact) tribological experiment. Materials: alloy steel (heat treated) vs. ABS plastic.
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3D printed ABS thermoplastic vs. steel. Dry sliding wear test in constant load & velocity ring on flat configuration. Test parameters: print layer thickness and orientation. Test symbol: 019_v_5
Open Research DataData gathered in sliding ring-on-block (flat contact) tribological experiment. Materials: alloy steel (heat treated) vs. ABS plastic.
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3D printed ABS thermoplastic vs. steel. Dry sliding wear test in constant load & velocity ring on flat configuration. Test parameters: print layer thickness and orientation. Test symbol: 009_h_5
Open Research DataData gathered in sliding ring-on-block (flat contact) tribological experiment. Materials: alloy steel (heat treated) vs. ABS plastic.
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3D printed ABS thermoplastic vs. steel. Dry sliding wear test in constant load & velocity ring on flat configuration. Test parameters: print layer thickness and orientation. Test symbol: 009_h_4
Open Research DataData gathered in sliding ring-on-block (flat contact) tribological experiment. Materials: alloy steel (heat treated) vs. ABS plastic.
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3D printed ABS thermoplastic vs. steel. Dry sliding wear test in constant load & velocity ring on flat configuration. Test parameters: print layer thickness and orientation. Test symbol: 039_h_4
Open Research DataData gathered in sliding ring-on-block (flat contact) tribological experiment. Materials: alloy steel (heat treated) vs. ABS plastic.
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3D printed ABS thermoplastic vs. steel. Dry sliding wear test in constant load & velocity ring on flat configuration. Test parameters: print layer thickness and orientation. Test symbol: 019_v_4
Open Research DataData gathered in sliding ring-on-block (flat contact) tribological experiment. Materials: alloy steel (heat treated) vs. ABS plastic.
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3D printed ABS thermoplastic vs. steel. Dry sliding wear test in constant load & velocity ring on flat configuration. Test parameters: print layer thickness and orientation. Test symbol: 019_h_5
Open Research DataData gathered in sliding ring-on-block (flat contact) tribological experiment. Materials: alloy steel (heat treated) vs. ABS plastic.
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3D printed ABS thermoplastic vs. steel. Dry sliding wear test in constant load & velocity ring on flat configuration. Test parameters: print layer thickness and orientation. Test symbol: 039_v_4
Open Research DataData gathered in sliding ring-on-block (flat contact) tribological experiment. Materials: alloy steel (heat treated) vs. ABS plastic.
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3D printed ABS thermoplastic vs. steel. Dry sliding wear test in constant load & velocity ring on flat configuration. Test parameters: print layer thickness and orientation. Test symbol: 009_v_4
Open Research DataData gathered in sliding ring-on-block (flat contact) tribological experiment. Materials: alloy steel (heat treated) vs. ABS plastic.
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3D printed ABS thermoplastic vs. steel. Dry sliding wear test in constant load & velocity ring on flat configuration. Test parameters: print layer thickness and orientation. Test symbol: 039_v_3
Open Research DataData gathered in sliding ring-on-block (flat contact) tribological experiment. Materials: alloy steel (heat treated) vs. ABS plastic.
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3D printed ABS thermoplastic vs. steel. Dry sliding wear test in constant load & velocity ring on flat configuration. Test parameters: print layer thickness and orientation. Test symbol: 019_v_3
Open Research DataData gathered in sliding ring-on-block (flat contact) tribological experiment. Materials: alloy steel (heat treated) vs. ABS plastic.
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3D printed ABS thermoplastic vs. steel. Dry sliding wear test in constant load & velocity ring on flat configuration. Test parameters: print layer thickness and orientation. Test symbol: 019_h_3
Open Research DataData gathered in sliding ring-on-block (flat contact) tribological experiment. Materials: alloy steel (heat treated) vs. ABS plastic.
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3D printed ABS thermoplastic vs. steel. Dry sliding wear test in constant load & velocity ring on flat configuration. Test parameters: print layer thickness and orientation. Test symbol: 039_h_5
Open Research DataData gathered in sliding ring-on-block (flat contact) tribological experiment. Materials: alloy steel (heat treated) vs. ABS plastic.
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3D printed ABS thermoplastic vs. steel. Dry sliding wear test in constant load & velocity ring on flat configuration. Test parameters: print layer thickness and orientation. Test symbol: 019_h_4
Open Research DataData gathered in sliding ring-on-block (flat contact) tribological experiment. Materials: alloy steel (heat treated) vs. ABS plastic.
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3D printed ABS thermoplastic vs. steel. Dry sliding wear test in constant load & velocity ring on flat configuration. Test parameters: print layer thickness and orientation. Test symbol: 039_v_2
Open Research DataData gathered in sliding ring-on-block (flat contact) tribological experiment. Materials: alloy steel (heat treated) vs. ABS plastic.
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3D printed ABS thermoplastic vs. steel. Dry sliding wear test in constant load & velocity ring on flat configuration. Test parameters: print layer thickness and orientation. Test symbol: 039_h_3
Open Research DataData gathered in sliding ring-on-block (flat contact) tribological experiment. Materials: alloy steel (heat treated) vs. ABS plastic.
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Mechanical testing of technical woven fabrics
PublicationThis article presents a review of technical fabrics testing methods used by the authors on the basis of their experience with research on properties of polytetrefluoroethylene-coated fabrics used for Forest Opera in Sopot (Poland). First, the different types of testing methods used for description of mechanical properties (uniaxial tensile tests, biaxial tensile tests and shear tests) of technical woven fabrics are described. The...
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Influence of selected submicron inorganic particles on mechanical and thermo-mechanical properties of unsaturated polyester/glass composites
PublicationIn this paper, the influence of different submicron-scaled particles (zinc oxide, titanium dioxide, or silica) on mechanical and thermo-mechanical properties of unsaturated polyester matrix composites reinforced with glass fabric was investigated. Surface morphology of obtained composites was also examined. At first inorganic particles were mechanically dispersed into unsaturated polyester resin system as per the calculated weight...
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Influence of thermal effects on mechanical properties of PVDF-coated fabric
PublicationThis paper describes the method of laboratory tests necessary for identification of temperature influence on mechanical properties of polyvinylidene fluoride-coated polyester fabric often used for tensile structures. Two nonlinear model descriptions are investigated. The first one is based on the piece-wise linear relations between stress and strain and the second one on the Murnaghan model of solid behavior. This paper is proposed...
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Mechanical properties of polyvinyl chloride-coated fabric under cyclic tests
PublicationThe aim of the present paper is to propose a method of laboratory tests necessary for the identification of mechanical properties of the coated fabric. The material parameters of the coated fabric AF 9032 are specified on the basis of the uniaxial and biaxial tensile tests. For the identification process, the techniques based on the least squares methods are used. Additionally, the uniaxial and biaxial cyclic tests are performed...
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Polyurethane/ground tire rubber composite foams based on polyglycerol: processing, mechanical and thermal properties
PublicationDuring the synthesis of rigid polyurethane foams, petrochemical polyol was substituted with polyglycerol, the product of thermo-catalytic polycondensation of waste glycerol, resulting from biodiesel production. Two types of ground tire rubbers, untreated and thermo-mechanically reclaimed, were used to obtain ‘‘green’’ polyurethane-polyglycerol composite foams. Samples were prepared by a single-step method for the ratio of NCO/OH...
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Eco-Friendly Electromagnetic Interference Shielding Materials from Flexible Reduced Graphene Oxide Filled Polycaprolactone/Polyaniline Nanocomposites
PublicationHybrid nanocomposites have the unique ability of enhancing material properties due to the existing synergistic effect of the fillers. In this study, the authors report such an eco-friendly hybrid nanocomposite comprising of polyaniline and reduced graphene oxide in polycaprolactone. The conducting polyaniline improved the processability of polycaprolactone, and the final composites were prepared by incorporating graphene oxide...
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Cavitation Erosion of P110 Steel in Different Drilling Muds
PublicationThe P110 steel specimens were subjected to ultrasonic cavitation erosion in different compositions of drilling muds and surfactant additive. The test procedure was based on ASTM-G-32 standard recommendations. API 5CT-P110 steel is used for pipes in oil and gas industry. The harsh environment and high velocity of flows poses corrosive and erosive threat on materials used there. The composition of drilling fluid influences its rheological...
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The use of GFRP tubes as load-bearing jackets in concrete-composite columns
PublicationThe paper presents the fields of applications of polymer composites in building structures. The use of composite glass fibre tubes is discussed in more detail. The laboratory methods used to test the mechanical properties of these pipes are presented. An original research program is presented, including six concrete-filled glass fibre tubes. The cylinders and columns made in this way were tested for their axial load capacity. Conclusions...
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Experimental study on the behaviour of steel columns under seismic-induced axial impact load
PublicationIt has been observed during major earthquakes that the so called soft-storey failure of an upper floor of a structure results in large impact load acting on structural members of the lower storeys. It may further lead to progressive collapse of the whole structure substantially intensifying human and material losses. Therefore, the aim of this paper is to investigate experimentally the behaviour of columns under bending (observed...
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Deregulacja polskiego rynku pracy
PublicationHistorycznie ukształtowana regulacja rynku pracy związana jest z jego infrastrukturą organizacyjno-prawną, tzn. przepisami dotyczącymi płac, czasu pracy i ochrony stosunku pracy. W opinii zwolenników deregulacji utrudnia ona elastyczne dostosowywanie się do rozmiarów zatrudnienia w zależności od zaistniałej sytuacji gospodarczej, powodując wzrost bezrobocia strukturalnego i wzrost kosztów pracy. Deregulacja rynku pracy związana...
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Minimum drag shape bodies moving in inviscid fluid - revisited
PublicationThis paper presents the classic approach to minimum drag shape body problem, moving at hypersonic speeds, leading to famous power law shapes with value of the exponent of 3/4. Two- and three-dimensional cases are considered. Furthermore, an exact pseudo solution is given and its uselessness is discussed. Two new solutions are introduced, namely an approximate solution due to form of the functional and solution by means of optimisation...
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Effect of applied standard wood machining fluid on colour and chemical composition of the machined wood surface
PublicationAppropriate monitoring of wood machining processes is a key issue to ensure the expected quality of the processed wood, expected efficiency and minimize energy consumption of production processes. A new trend is the design of environmentally friendly machining fluids. In this paper, as a preliminary study in this field, the effect of applied standard wood machining fluid on changes in the colour and chemical composition of the...
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Two-Step Model Based Adaptive Controller for Dissolved Oxygen Control in Sequencing Wastewater Batch Reactor
PublicationDissolved Oxygen (DO) concentration is a crucial parameter for efficient operation of biological processes taking place in the activated sludge Wastewater Treatment Plant (WWTP). High-quality DO control is difficult to achieve because of complex nonlinear behavior of the plant and substantial influent disturbances. A method to improve the Direct Model Reference Adaptive Control (DMRAC) technology in application to DO tracking for...
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Fluid Mechanics, L/L/E, DaPE, sem. 04, summer 21/22 (PG_00050282)
e-Learning CoursesLECTURES Introduction and basic definitions. Properties of fluids. Models of fluids. Fluids in equilibrium. Determination of hydrostatic forces. Archimedes" law. Methods of fluid flow description. General motion of fluid. Deformation of fluid element. Vortex motion of fluid. Principles of conservation of mass, momentum and energy. Balance of entropy. Navier-Stokes equation. Bernoulli equation. Similarity of flow phenomena. Potential...