Filters
total: 1345
-
Catalog
- Publications 1135 available results
- Journals 49 available results
- Conferences 19 available results
- People 22 available results
- Inventions 3 available results
- Projects 2 available results
- Research Teams 4 available results
- e-Learning Courses 89 available results
- Open Research Data 22 available results
displaying 1000 best results Help
Search results for: MENISCUS GEOMETRY
-
On the current state of dovetail wall-corner joints in wooden Greek Catholic churches in Polish Subcarpathia with structural and sensitivity analyses
PublicationThis paper describes the current condition of some dovetail joints which form the wall corners of two Greek Catholic churches of wooden construction in Polish Subcarpathia. It also gives the historical background of the sacral architecture of that region. The two structures, which represent the same type of log corner joints are situated in Chotylub and Cewków. The buildings were examined e.g. for damage, wood moisture content,...
-
Short and Long Term Measurements in Assessment of FRP Composite Footbridge Behavior
PublicationThe paper presents application of different sensors for the purpose of short and long term measurements, as well as a structural health monitoring (SHM) system to assess the behavior of a novel fiber reinforced plastics (FRP) composite footbridge. The aim is to present a thorough and concise description of these sensors networks and results gathered with their aid during in situ measurement of strains, displacements, and vibrations,...
-
Modelling of the Heat Flux Density Distribution for Laser Beam Welding
PublicationGreat interest of the laser beam welding in industry is a new theoretical task, making planning the welding procedure specification and the quality control of welded joints easier. Estimating and calculating the dimensions of a weld pool and temperature distribution near weld mainly concern heat source modelling. In the presented work calculations of welding pool shape and thermal field for cylindrical-powered-normally model of...
-
Implementation of spatial information for monitoring and analysis of the area around the port using laser scanning techniques
PublicationNowadays, maritime infrastructure is heavily exploited, which requires monitoring. The article presents the implementation of spatial information which are point clouds for monitoring and analysis of the area around the port (buildings and wharves). For this study, point clouds coming from terrestrial (TLS) and airborne laser scanning (ALS), each of them having different accuracy, were used. An important part of the analysis was...
-
Objective relaxation algorithm for reliable simulation-driven size reduction of antenna structure
PublicationThis letter investigates reliable size reduction of antennas through electromagnetic-driven optimization. It is demonstrated that conventional formulation of the design task by direct footprint miniaturization with imposing constraints on electrical performance parameters may not lead to optimum results. The reason is that—in a typical antenna structure—only a few geometry parameters explicitly determine the antenna footprint,...
-
Rapid EM-driven antenna dimension scaling through inverse modeling
PublicationIn this letter, a computationally feasible technique for dimension scaling of antenna structures is introduced. The proposed methodology is based on inverse surrogate modeling where the geometry parameters of the antenna structure of interest are explicitly related to the operating frequency. The surrogate model is identified based on a few antenna designs optimized for selected reference frequencies. For the sake of computational...
-
A compact microstrip rat-race coupler constituted by nonuniform transmission lines
PublicationIn this work, a step-by-step development of a compact microstrip rat-race coupler (RRC) has been presented and discussed. A high degree of miniaturization has been obtained by substituting six quarter-wavelength uniform atomic building blocks of a RRC by their nonuniform counterparts. The miniaturization procedure has been realized in three progressive steps: (i) the first layout solution of a miniaturized RRC has been acquired...
-
Measurements of Spectral Spatial Distribution of Scattering Materials for Rear Projection Screens used in Virtual Reality Systems
PublicationRapid development of computing and visualisation systems has resulted in an unprecedented capability to display, in real time, realistic computer-generated worlds. Advanced techniques, including three-dimensional (3D) projection, supplemented by multi-channel surround sound, create immersive environments whose applications range from entertainment to military to scientific. One of the most advanced virtual reality systems are CAVE-type...
-
Rectangular Waveguide Filters Based on Deformed Dual-Mode Cavity Resonators
PublicationIn this paper, a novel design for rectangular waveguide filters with deformed dual-mode (DM) cavity resonators is demonstrated. The new resonant cavity shape is a result of applying shape deformation to the basic rectangular cavity to enable its dual-mode operation. Internal coupling between the two orthogonal cavity modes is realized by geometry deformation, eliminating the need for additional coupling elements. The designs are...
-
Framework for extracting rails and setting-out railway line axis based on UAV photogrammetric measurements
PublicationTechnical diagnostics enables assessing the current technical condition of a railway line and adjacent infrastructure, and forecasting its changes over a specific time horizon. One of its elements is the periodic monitoring of rail position and their geometry. This article presents a new framework for the setting-out of a railway track axis. The process presented in the manuscript is based on the specific filtration and extraction...
-
Fast Design Optimization of Waveguide Filters Applying Shape Deformation Techniques
PublicationThis paper presents an efficient design of microwave filters by means of geometry optimization using shape deformation techniques. This design procedure allows for modelling complex 3D geometries which can be fabricated by additive manufacturing (AM). Shape deforming operations are based on radial basis function (RBF) interpolation and are integrated into an electromagnetic field simulator based on the 3D finiteelement method (FEM)....
-
Fractographic-fractal dimension correlation with crack initiation and fatigue life for notched aluminium alloys under bending load
PublicationIn this study, fatigue fracture surfaces of aluminium alloy 2017-T4 notched specimens were investigated under cyclic bending to find an alternative failure loading index.. The surface topographies were measured on the entire fracture area with an optical profilometer for different loading conditions. Fatigue crack initiation life Ni and total fatigue life Nf were examined using standard surface topography parameters (such as, root...
-
Validation study on a new semi-empirical method for the prediction of added resistance in waves of arbitrary heading in analyzing ship speed trial results
PublicationThis paper describes an open and extensive validation study carried out by the Specialist Committee on Ships in Operation at Sea (SOS) of the International Towing Tank Conference (ITTC) on the newly developed SHOPERA-NTUA-NTU-MARIC (SNNM) wave-added resistance prediction method. The SNNM method aims at a simple, fast and transparent determination of the added resistance in regular waves of arbitrary encounter directions, even when...
-
Portico Farmhouses of the Vistula Delta: Architecture, Current State and Finite Element Modelling of Timber Roof Truss under Material and Cross-section Uncertainty
PublicationThe article focuses on the oldest surviving I-type portico houses located in the Vistula Delta, which were built in the 17th and 18th centuries. The study describes the houses’ origins, structure, details of roof structures and technical condition, and it also includes numerical modelling of a roof truss and its mechanical analysis. Numerical models of the roof trusses are defined and analysed by means of the finite element method....
-
FEM modelling of stress and strain distribution in weld joints of steel sandwich panels
PublicationThe development of laser welding technology has enabled the mass production of thin-walled structures, including steel sandwich panels. The technology of joining plating panels with stiffeners by welding allows us to create joints with a specific geometry and material properties. In comparison with other types of joints, laser welds are characterized by their specific behaviour under cyclic load and, as a consequence, a different...
-
Energy Modeling of Single-Family Houses in the Conceptual Phase
PublicationThe aim of the article is to identify the potential impact of the latest commercial digital tools for building energy analysis on the everyday architectural practice in Poland in the context of typology and energy optimization of single –family houses. The reason for this survey is that “architect friendly” interfaces simulation results’ visualization and energy analysis tools are not given deserved attention in the architectural...
-
Ultrasonic Tomography of Brick Columns Based on FEM Calculations
PublicationUltrasonic tomography is one of the most developed method of non-destructive testing. Despite being used mainly in medicine, it is becoming more and more popular as a method for monitoring of structural elements. It allows to examine the internal structure and technical condition of the tested element. This paper investigates the influence of crosssectional geometry on an obtained tomographic image. Wave propagation signals were...
-
Comparative analysis of different numerical models of a steel radial gate
PublicationHydrotechnical structures are important components in water management system and general flooding safety. Their reliability should be ensured since potential damage might lead to catastrophic consequences. Weir gates are considered to be highly vulnerable elements of each hydro power plant, with regard to its dynamic resistance. The aim of the paper is to compare different numerical models and their influence on the results of...
-
Discrete-continuous optimisation of an axial flow blood pump
PublicationThis paper presents results of discrete-continuous optimisation of an axial flow blood pump. Evolution Strategies (ES) are used as a global optimisation method in order to localise the optimal solution in relatively short time. The whole optimisation process is fully automated. This also applies to geometry modelling. Numerical simulations of the flow inside the pump is performed by means of the Reynolds-Average Navier-Stokes...
-
LDFEM analysis of FDP auger installation in cohesive soil
PublicationThis paper deals with large deformation finite element (LDFE) preliminary modelling of Full Displacement Pile (FDP) installation in cohesive soil deposit located in Jazowa, Poland. The detailed FDP auger geometry is applied and the drilling process is modelled with full 3D Coupled Eulerian-Lagrangian (CEL) formulation. The total stress approach and elastic-perfectly plastic model with rate-dependent Mises plasticity is used. The...
-
Design and optimization of a novel miniaturized low-profile circularly polarized wide-slot antenna
PublicationThis paper presents a novel structure of a compact circularly polarized (CP) antenna. CP is obtained using a parasitic quasi-rectangular strip placed coplanar to the feedline. A ground plane perturbation combined with the asymmetric geometry of the coplanar waveguide ground planes is utilized to excite additional CP modes. All antenna dimensions are rigorously optimized to achieve the best possible performance in terms of the impedance...
-
Analityczna metoda projektowania łuków odwrotnych
PublicationW pracy przedstawiono nową metodę projektowania rejonu zmiany kierunku trasy kolejowej, dostosowaną do techniki Mobilnych Pomiarów Satelitarnych. Metoda ta może się okazać szczególnie przydatna wówczas, gdy obydwu prostych kierunków trasy nie można połączyć w sposób elementarny, stosując łuk kołowy z krzywymi przejściowymi; dotyczy to również. zastosowania łuku koszowego. Jedynym rozwiązaniem staje się wówczas wprowadzenie do układu...
-
Graphical interface adaption for children to explain astronomy proportions and distances
PublicationMobile Science Center is a Polish project that seeks to bring astronomy knowledge to wider social groups through various applications. In its development it is necessary to design a graphical interface that explains a concept that is difficult to assimilate such as spatial proportions and distances. This paper develops a framework to create graphical representations that explain this learning to the target audience of children....
-
Jakub Jabłoński inż.
PeopleEducation In 2016 Jakub Jabłoński finished Zbigniew Herbert XX High School in Gdańsk (math-physics-IT profile). In 2017 he started an undergraduate course in Civil Engineering at the Faculty of Civil and Environmental Engineering of the Gdańsk University of Technology, which he graduated in 2021 with the title of Bachelor of Science in Engineering. During his studies he took active part in the scientific association "Hevelius". Employment About...
-
FEM modeling of structures based on close range digital photogrammetry
PublicationPraca dotyczy metodologii przygotowania modelu konstrukcji istniejącej do analizy mechanicznej metodą element ow skończonych. MOdelowanie geometrii budowli jest oparte na danych pozyskanych z pomiarów fotogrametrycznych. Praca wskazuje na możliwości oraz efektywność zastosowania metod optometrycznych w rewitalizacji budowli zabytkowych, an przykładzie modelu dachu drewnianego.
-
A computer system for the complete design of ship propellers
PublicationPraca zawiera opis metody obliczeniowej pozwalającej na zaprojektowanie okrętowej śruby napędowej dla również obliczeniowo wyznaczonego niejednorodnego pola prędkości za kadłubem statku o znanej geometrii i parametrach ruchu. Metoda pozwala na właściwe ujęcie efektu skali i konsekwencji obecności płetwy sterowej za projektowaną śrubą.
-
Główne elementy projektu regatowej łodzi podwodnej „Nautilus” napędzanej mechanicznie
PublicationW pracy przedstawiono wybrane rozwiązania projektu podwodnego pojazdu regatowego o napędzie mięśniowym: analizę oporową kadłuba, koncepcję systemu sterującego, rozwiązania układu napędowego oraz geometrię pędnika. Projekt został wykonany przez Koło Naukowe CAD/CAE Studentów PG „PIKSEL”, działające na Wydziale Oceanotechniki i Okrętownictwa Politechniki Gdańskiej.
-
Constructive entanglement test from triangle inequality
PublicationWe derive a simple lower bound on the geometric measure of entanglement for mixed quantum states in the case of a general multipartite system. The main ingredient of the presented derivation is the triangle inequality applied to the root infidelity distance in the space of density matrices. The obtained bound leads to entanglement criteria with a straightforward interpretation. The proposed criteria provide an experimentally accessible,...
-
Przedmiot Wyrównawczy (GiGK i MF) 2022/2023
e-Learning CoursesKurs wyrównawczy dla specjalności Matematyka Finansowa oraz Geometria i Grafika Komputerowa. Kurs wyrównawczy dla specjalności Analityk Danych znajduje się tutaj: https://enauczanie.pg.edu.pl/moodle/course/view.php?id=25761
-
AVHRR Level1CD covering Baltic Sea area year 2005
Open Research DataThe dataset contains data derived from recordings of the AVHRR/3 radiometer operating on board the NOAA POES (Polar Orbiting Environmental Satellites) Series - 5th Generation Satellites covering the Baltic Sea area. The satellite data was recorded in the years 2000-2012 directly by the HRPT station installed at the University of Gdańsk. The registration...
-
AVHRR Level1CD covering Baltic Sea area year 2004
Open Research DataThe dataset contains data derived from recordings of the AVHRR/3 radiometer operating on board the NOAA POES (Polar Orbiting Environmental Satellites) Series - 5th Generation Satellites covering the Baltic Sea area. The satellite data was recorded in the years 2000-2012 directly by the HRPT station installed at the University of Gdańsk. The registration...
-
AVHRR Level1CD covering Baltic Sea area year 2003
Open Research DataThe dataset contains data derived from recordings of the AVHRR/3 radiometer operating on board the NOAA POES (Polar Orbiting Environmental Satellites) Series - 5th Generation Satellites covering the Baltic Sea area. The satellite data was recorded in the years 2000-2012 directly by the HRPT station installed at the University of Gdańsk. The registration...
-
AVHRR Level1CD covering Baltic Sea area year 2002
Open Research DataThe dataset contains data derived from recordings of the AVHRR/3 radiometer operating on board the NOAA POES (Polar Orbiting Environmental Satellites) Series - 5th Generation Satellites covering the Baltic Sea area. The satellite data was recorded in the years 2000-2012 directly by the HRPT station installed at the University of Gdańsk. The registration...
-
Badanie anizotropii magnetycznej oraz dynamiki relaksacji dla nowych heteroleptycznych silanotiolanów Co(II) o geometrii tetraedrycznej.
ProjectsProject realized in Department of Inorganic Chemistry according to DECYZJA DYREKTORA NARODOWEGO CENTRUM NAUKI Nr DEC-2021/05/X/ST4/00488 agreement from 2021-10-18
-
Simulation of damage process of containership's side structure due to collision with a rock
PublicationW artykule przedstawiono wyniki uproszczonego modelowania numerycznego procesu kolizji burty kontenerowca ze skałą. Analiza wyników modelowania pozwala wyciągnąć wnioski o charakterze zjawiska jak również określić obszar i głębokość uszkodzenia wywołanego przez penetrującą skałę w celu doboru wymiarów geometrii i wypełniacza dla drugiej bariery ochronnej.
-
Purely quantum superadditivity of classical capacities of quantum multiple access channels
PublicationWe are studying classical capacities of quantum memoryless multiaccess channels in geometric terms and we are revealing a break of additivity of the Holevo-like capacity. This effect is a purely quantum mechanical one, since, as we point out, the capacity regions of all classical memoryless multiaccess channels are additive. It is the first such effect revealed in the field of classical information transmission via quantum channels.
-
Wpływ rozmieszczenia źródeł w rozproszonym systemie rozgłoszeniowym na zrozumiałość mowy.
PublicationDźwiękowe systemy ostrzegawcze instalowane w obiektach użyteczności publicznej muszą zapewniać odpowiednio wysoką zrozumiałość mowy. W praktyce systemy nagłośnieniowe nie zawsze spełniają to kryterium. Referat przedstawia badania symulacyjne dwóch systemów wykorzystujących rozproszone układy źródeł.Celem badań jest określenie związków między geometrią rozkładu źródeł a zrozumiałością mierzoną parametrem RASTI.
-
Modernization of tram lines with the use of railway design standards
PublicationThe article presents the main differences between the process of upgrading railway and tram routes. Geometrical layout designing is an issue of the interest. Railway designing rules that may be helpful in the design of the modernization are specified.
-
O zbieżności rozwiązań w nieliniowym mikropolarnym ośrodku sprężysto-plastycznym - zastosowanie elementów skończonych wyższego rzędu.
PublicationEfekty lokalizacji w nieliniowym geometrycznie sprężysto-plastycznym mikropolarnym ośrodku z osłabieniem materiału. Hipotezy Hubera-Misesa-Hencky’ego i Druckera-Pragera. Rozwiązanie równań sprężysto-plastycznych przy użyciu algorytmu powrotnego. Opis zastosowanych elementów skończonych. Przykłady numeryczne obliczeń w geotechnice.
-
obieralne: Zastosowanie "foldable tessellation" w projektowaniu fasad i przykryć architektonicznych
e-Learning CoursesW dobie cyfrowej fabrykacji oraz oprogramowania, wiedza z zakresu geometrii pozwala na skuteczne i świadome stosowanie nowych narzędzi. Jedną z dziedzin geometrii która znajduje bezpośrednie zastosowanie w projektowaniu architektonicznym są origami modułowe oraz “origami tessellation” które pozwalają na tworzenie zaawansowanych geometrii z wykorzystaniem powtarzających się paneli oraz pojedynczego arkusza materiału, ułatwiając...
-
Rhythm and Colours of the Angles
PublicationABSTRACT The game of space was and still is a crucial aspect of visual arts. The aim of this study is to examine how the arrangement of hues, rhythms and angles of various polygons can create an impression of depth and movement on a flat surface. The so-called Penrose tiling and Ulam's spiral are mathematical models that have been applied for the painting experiment. There is a vast amount of evidence gathered over the ages that...
-
O topologii w architekturze
PublicationOpracowanie dotyczy inspiracji we współczesnej architekturze topologicznymi koncepcjami. Wzbogacenie warsztatu projektowego o komputerowe narzędzia obliczeniowe umożliwiające tworzenie i modyfikowanie unikalnej, krzywoliniowej, geometrii katalizuje formalne i konceptualne eksploracje przestrzeni topologicznej przez awangardowych projektantów. Podejście topologiczne manifestuje się zarówno w dynamice procesu projektowania opartego...
-
Performance Assessment of Using Docker for Selected MPI Applications in a Parallel Environment Based on Commodity Hardware
PublicationIn the paper, we perform detailed performance analysis of three parallel MPI applications run in a parallel environment based on commodity hardware, using Docker and bare-metal configurations. The testbed applications are representative of the most typical parallel processing paradigms: master–slave, geometric Single Program Multiple Data (SPMD) as well as divide-and-conquer and feature characteristic computational and communication...
-
Materiały i fabrykacja w kontekście paradygmatu cyfrowego w architekturze
PublicationOpracowanie dotyczy wpływu jaki na współczesną architekturę ma rozwój nauki o materiałach i technologii CNC. Nowe technologie pozwalają na realizację wielokrzywiznowej geometrii oraz uzyskiwanie unikalnych efektów materiałowych z wykorzystaniem zarówno nowych budulców jakimi są materiały kompozytowe i polimery jak również tradycyjnych materiałów takich jak cegła i kamień.
-
Obliczenia i projekt nowego łożyska nr 1 turbozespołu TG-2 EC w Gdańsku
PublicationCelem pracy było wykonanie optymalizacji geometrii łożyska nr 1 turbozespołu TG2 w celu uzyskania maksymalnej poprawy własności dynamicznych łożyska. W tym celu przeanalizowano kilkanaście różnych wariantów geometrycznych i wybrano najbardziej optymalne dla tego przypadku rozwiązanie. Opracowano dokumentację techniczną nowego łożyska. Łożysko wdrożono w turbinie parowej EC Gdańsk.
-
PROBABILISTIC ANALYSIS OF A SPACE TRUSS BY MEANS OF A MULTIDIMENSIONAL VARIABLE DESCRIPTION
PublicationThe objective of this paper is to present a variant of the point estimate method (PEM) to determine mean values and standard deviations of limit loads of engineering structures. This approach is illustrated by limit state analysis of a space truss, considering geometric and material imperfections. The calculations were performed for different random models, so the influence of random parameters on the limit load of the truss can...
-
Materiały i fabrykacja w kontekście paradygmatu cyfrowego w architekturze
PublicationOpracowanie dotyczy wpływu jaki na współczesną architekturę ma rozwój nauki o materiałach i technologii CNC. Nowe technologie pozwalają na realizację wielokrzywiznowej geometrii oraz uzyskiwanie unikalnych efektów materiałowych z wykorzystaniem zarówno nowych budulców jakimi są materiały kompozytowe i polimery jak również tradycyjnych materiałów takich jak cegła i kamień.
-
Two dimensional inverse solution for diagonal pumps
PublicationW pracy przedstawiono rozwiązanie zadania odwrotnego dla wirnika i kierownicy pompy diagonalnej. Dla założonego kształtu powierzchni prądu wyznaczono kształt łopatek obu palisad. Geometria kanałów łopatkowych została wyznaczona w wyniku rozwiązania układu równań zapisanych w krzywoliniowym układzie współrzędnych. W pracy przedstawiono fotografie wirnika wykonanego techniką Rapid Prototyping.
-
FE investigations of the effect of fluctuating local tensile strength on coupled energetic-statistical size effect in concrete beams
PublicationThe effect of fluctuating local tensile strength on a coupled energetic-statistical size effect in plain concrete beams under bending was numerically investigated. First, the influence of varying autocorrelation length of the random field describing a spatial variation of local tensile strength was studied. Next, the influence of the coefficient of variation of local tensile strength was analyzed. The numerical FE investigations...
-
Mechatronics design, modelling and controlling of the Stewart-Gough platform
PublicationThis paper presents a mechatronics design of a low cost Stewart-Gough platform (SGP) with rotary actuators. The designed SGP is supposed to be applied in a ball & plate control system. The synthesis of the ball & plate control system is also within the subject of the paper. A mechatronics design process of the SGP was conducted with computer-aided design (CAD) software. Unique analytical solutions of an inverse kinematics problem...