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Minimal surfaces and conservation laws for bidimensional structures
PublikacjaWe discuss conservation laws for thin structures which could be modeled as a material minimal surface, i.e., a surface with zero mean curvatures. The models of an elastic membrane and micropolar (six-parameter) shell undergoing finite deformations are considered. We show that for a minimal surface, it is possible to formulate a conservation law similar to three-dimensional non-linear elasticity. It brings us a path-independent...
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Detection of debonding in reinforced concrete beams using ultrasonic transmission tomography and hybrid ray tracing technique
PublikacjaThis paper concerns inspection of reinforced concrete elements, with particular emphasis on assessing the quality of the adhesive connection between steel and concrete. A novel theoretical model was developed to determine the paths of transmitted, refracted and reflected elastic waves as well as a creeping wave propagated along the inclusion surface. Imaging the internal structure of tested beams was based on wave propagation measurements...
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Stability of an imperfect truss loaded by wind
PublikacjaThe present paper is devoted to the numerical research of stability of a truss loaded by wind and stiffened by elastic supports located at the top chord. The lateral braces or lateral and torsional braces were taken into account. In this paper, the linear buckling analysis re- sults for the beam and shell model were presented. Two different shapes of initial geometric imperfections were considered in the non-linear static analysis...
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Analysis of sloping brace stiffness influence on stability and load bearing capacity of a truss
PublikacjaThe paper is focused on the numerical study of stability and load bearing capacity of a truss with side elastic braces. The structure is made in reality. The rotational and sliding brace stiffnesses were taken into account. Linear buckling analysis and non-linear static analysis with geometric and material nonlinearity were performed for the beam and shell model of the truss with respect to the angle of sloping braces. As a result...
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Effect of underwater local cavity welding method conditions on diffusible hydrogen content in deposited metal
PublikacjaOne of the methods with great potential for applications in underwater repairs is local cavity welding. In local cavity method, cooling conditions and diffusible hydrogen amount in weld metal are nearly the same as those existed during welding in the air. This paper presents the results of literature survey and preliminary tests of the effect of local cavity welding conditions on diffusible hydrogen amount in a deposited metal....
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Nonlinear resultant theory of shells accounting for thermodiffusion
PublikacjaThe complete nonlinear resultant 2D model of shell thermodiffusion is developed. All 2D balance laws and the entropy imbalance are formulated by direct through-the-thickness integration of respective 3D laws of continuum thermodiffusion. This leads to a more rich thermodynamic structure of our 2D model with several additional 2D fields not present in the 3D parent model. Constitutive equations of elastic thermodiffusive shells...
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2022-2023 - Strenght of materials towards applications, PG_00053661
Kursy OnlineThe course is mainly dedicated to the DAPE Students. From the theoretical point of view the course consists of the following problems to be discussed during the lectures and exercises: -fundamentals of strength of materials -basic structures and environment -loads on structures -strength of materials: tension, stress, analysis of stress and strain, bending moments and shearing forces, longitudinal and shearing stress in beams,...
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Strenght of materials towards applications , PG_00053661
Kursy OnlineThe course is dedicated to the DAPE WIMiO Students. From the theoretical point of view the course consists of the following problems to be discussed during the lectures: -fundamentals of strength of materials -basic structures and environment -loads on structures -strength of materials: tension, stress, analysis of stress and strain, bending moments and shearing forces, longitudinal and shearing stress in beams, bending stress...
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Surface finite viscoelasticity and surface anti-plane waves
PublikacjaWe introduce the surface viscoelasticity under finite deformations. The theory is straightforward generalization of the Gurtin–Murdoch model to materials with fading memory. Surface viscoelasticity may reflect some surface related creep/stress relaxation phenomena observed at small scales. Discussed model could also describe thin inelastic coatings or thin interfacial layers. The constitutive equations for surface stresses are...
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Assessment of Wooden Beams from Historical Buildings Using Ultrasonic Transmission Tomography
PublikacjaThe 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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ANALYSIS OF BRACE STIFFNESS INFLUENCE ON STABILITY OF THE TRUSS
PublikacjaThe 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
PublikacjaThe 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
PublikacjaCalculations 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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Acoustical images of the Gulf of Gdansk
PublikacjaAcoustic 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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A two dimensional approach for modelling of pennate muscle behaviour
PublikacjaThe 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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Geometrically nonlinear FEM analysis of FGM shells based on neutral physical surface approach in 6-parameter shell theory
PublikacjaThe 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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Identification of Shear Modulus Parameters of Half-space Inhomogeneous by Depth
PublikacjaThe 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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Potential of Functionalized Polyolefins in a Sustainable Polymer Economy: Synthetic Strategies and Applications
PublikacjaPolymers play a crucial role in our modern life as no other material exists that is so versatile, moldable, and lightweight. Consequently, the demand for polymers will continue to grow with the human population, modernization, and technological developments. However, depleted fossil resources, increasing plastic waste production, ocean pollution, and related growing emission of greenhouse gases has led to a change in the way we...
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Influence of Bingham fluid viscosity on energy performances of a vortex chamber pump
PublikacjaOne of the problems in the development of coal-water technologies is the use of reliable and long-lasting pumps. To date, classic pumps, due to the use of mechanical moving parts and seals, are subject to rapid abrasive wear. The solution to this problem can lie in the creation of new vortex chamber pumps developed by the authors. They are highly reliable, simple in design and have no moving parts. The object of this paper consists...
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Biobased Ultralow-Density Polyurethane Foams with Enhanced Recyclability
PublikacjaPolyurethane (PUR) foams are widely used in many engineering applications, but their efficient recycling has remained a major challenge for many years. This study presents a novel strategy of incorporating hydrolyzable ester units into the PUR structure to enhance PUR foam recyclability. The present ecodesign concept of PUR materials enables fully the replacement of petrochemical polyols with biobased alternatives and production...
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Degradation of implantable materials – in vivo and in vitro research
PublikacjaThe article concerns the biological and electrochemical degradation of metallic implants in vivo and in vitro studies. The in vivo research dealt with degradation of plates used to join bones, as well as endoprostheses. The most common damages were: metalosis, breaking in the microstructure changes, breaking in area of holes, as well as plastic deformation throughout the length of an implant. The material used for the research...
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Raman Spectra Measurements for Chemical Identifications - Aspect of Uncertainty Sources and Reduction of Their Effects
PublikacjaRaman spectrometers enable fast and non-contact identification of examined chemicals. These devices measure Raman spectra and compare with the spectra database to identify unknown and often illicit chemicals (e.g. drugs, explosives) usually without any sample preparation. Raman spectra measurements are a challenge due to noise and interferences present outside the laboratories (field applications). The design of a portable Raman...
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Manufacturing and Recycling Impact on Environmental Life Cycle Assessment of Innovative Wind Power Plant Part 1/2
PublikacjaWind power plants are considered as ecologically-clean source of energy. However, manufacturing processes cannot be treated that way. Manufacturing processes consume huge amount of electrical and thermal energy and significant amount of materials, e.g. steel, polymers, oils and lubricants. All of the above could be potentially harmful for environment. There are not many works and publications regarding life-cycle analysis of wind...
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Challenges and recent advances in bio-based isocyanate production.
PublikacjaPolyurethanes (PUs) are key players in the plastics industry. According to the Global Polyurethane Market (2019–2023), their value in the global market reached $95.13 billion in 2019 and is expected to grow at a compound annual growth rate of 12%. This is in line with the increase in the number of research papers and patents on the synthesis and application of petroleum-based PUs (P-PUs) and biomass or green PUs (G-PUs) (from 67 657...
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Air bubble and oil droplet interactions in centrifugal fields during air-sparged hydrocyclone flotation
PublikacjaWzajemne oddziaływania pęcherzyka powietrza i kropli oleju w polu siły odśrodkowej były rozpatrywane w odniesieniu do warunków procesowych obecnych podczas flotacji za pomocą hydrocyklonu. Efektywności zetknięcia się kropli oleju z pęcherzykami powietrza zostały zidentyfikowane jako znacząco mniejsze w porównaniu do efektywności zetknięcia się cząstek minerałów. Wyznaczono czasy zderzenia i styku ślizgowego. Chociaż przyczepność...
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Scuffing and rolling contact fatigue resistance of discrete laser spot hardened austempered ductile iron
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Regional effects of amphetamine, cocaine, nomifensine and GBR 12909 on the dynamics of dopamine release and metabolism in the rat brain
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Selective Laser Sintering And Melting Of Pristine Titanium And Titanium Ti6Al4V Alloy Powders And Selection Of Chemical Environment For Etching Of Such Materials
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Microscopic Imaging to Visualize the Distribution of Dietary Nucleic Acids in Food Products of Various Origins
PublikacjaDietary nucleic acids (dietNAs) are being increasingly recognized as important food components with nutritional value. However, the precise dietary recommendations for dietNAs are limited, because established methods for determining the quantity and nutritional role of dietNAs are still lacking. One of the tools to narrow this gap could be microscopic imaging, as a convenient approach to visualize the abundance and distribution...
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Effect of Hydroxypropylation and Beta-Amylase Treatment on Complexation of Debranched Starch With Naringenin
PublikacjaNaringenin exhibits many health benefits but it has limited water solubility and consequently low bioavailability. The objective of this study is to investigate the effect of hydroxypropylation and enzymatic treatments on starch complexation with naringenin. Potato starch and Hylon VII are hydroxypropylated to two substitution degrees and then debranched or debranched/β‐amylase treated prior to complexing with naringenin. Both...
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Effect of Acetylation and Beta‐Amylase Treatment on Complexation of Debranched Starch with Naringenin
PublikacjaStarch inclusion complexation has been shown to improve solubility of water insoluble molecules. Potato starch and Hylon VII are acetylated at two levels and then debranched alone or combined with β‐amylase hydrolysis, and its complexes with naringenin are prepared in aqueous conditions and characterized in this study. Both soluble and insoluble complexes are formed with the soluble complex present in the supernatant and the insoluble...
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Thermal analysis and experimental verification of permanent magnet synchronous motor by combining lumped-parameter thermal networks with analytical method
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ENTREPRENEURSHIP AND CREATIVITY - summer term 2021/22
Kursy OnlineThe aim of the course is to acquaint students with entrepreneurship as a phenomenon, increase their pro-entrepreneurial attitudes and develop skills necessary in entrepreneurship process. Special emphasis will be placed on fashion business as representing creative industry. The main objectives are as follows: Learn how to prepare a business model canvas and business plan. Know the backstage of the fashion industry. Identify...
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Architectural and urban theories in urban regeneration
Kursy OnlineThis course deals with key issues associated with contemporary architectural and urban teories associated with transformation and revitalization of the distressed / degradated areas and buildings / objects. The architectural topics will be presented by dr Ksenia Piątkowska and Prof. Lucyna Nyka, while urban topics will be discussed by Prof. Piotr Lorens. Particular topics and themes will be presented according to the individual...
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ENTREPRENEURSHIP AND CREATIVITY - summer term 2023/24
Kursy OnlineThe aim of the course is to acquaint students with entrepreneurship as a phenomenon, increase their pro-entrepreneurial attitudes and develop skills necessary in entrepreneurship process. Special emphasis will be placed on fashion business as representing creative industry. The main objectives are as follows: Learn how to prepare a business model canvas and business plan. Know the backstage of the fashion industry. Identify...
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Space and Landscape in a Global Context
Kursy OnlineModule SPACE AND LANDSCAPE IN A GLOBAL CONTEXT (2022/2023, autumn semester) Objective The objective of the module is to debate different approaches to managing spatial development and contemporary issues in a global context. The course is founded on the students' knowledge about urban planning and instruments used to make them better places both for people and the environment. Course proceedings Lectures and classes run online...
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MANAGEMENT AND ENVIRONMENT MONITORING 2021/22 - summer
Kursy OnlineThe course is dedicated to students at 3 semester of Environmental Engineering. The subject is related to two issues. First is monitoring of the environment- different component of the environment like water, air, soil. Conditions necessary for reliable monitoring and analysis of the results of this monitoring are also discussed. Second is management and covers: Historical development of environmental strategies for protection...
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Steam and Gas Turbines Constuction_ seminar/project
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Project application workshops_Inter PhD_electronics, telecommunications and informatics
Kursy Onlinedisciplinary field: ETI / The aim of the course is to provide the necessary information related to the search for sources of funding for scientific research and development work, with particular emphasis on competitions addressed to young researchers. Procedures for writing grant applications will be presented.
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Material Engineering and Manufacturing Technology kopiuj 1
Kursy OnlineSOME MODERN MATERIALS IN OCEAN ENGINEERING (Lectures)
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Building Structures and Technologies (BSc 2022/2023)
Kursy OnlineWykład przeznaczony dla Studentów Wydziału Architektury (sem. 5 inż.). Tematem wykładów są podstawy projektowania konstrukcji metalowych.
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Groundwater and Soil Protection EE 22/23
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Biomaterials processing and testing methods 2022/23
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Solid State Electronics and Nanoelectronics 2021/22
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Robotics for human health and performance 03.2022
Kursy OnlineThis course is to provide knowledge in area of biomechanics, necessary to design instrumentation for human health and performance, and automatics necessary to design simple instrumentation as well as about human-robot interface.
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Hydro and marine civil engineering (2023-2024)
Kursy OnlineKurs realizowany na Wydziale Inżynierii Lądowej i Środowiska (WILiŚ) Politechniki Gdańskiej. Studia: II stopnia - magisterskie, stacjonarne Kierunek: Budownictwo Semestr: 1 (letni) Presentation of basic hydro and marine civil engineering structures together with basic computational procedures for determining environmental forces acting on a structure (vertical-wall breakwater, rubble mound breakwater, submarine pipelines...
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Web intelligence and its applications 2022/2023
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Physical and chemical basis of energy generation
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Digital Platforms and Services - STAC - 2023/2024
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Civilization Threats and Sustainable Development -2022/23
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