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Fragility analysis of structural pounding between adjacent structures arranged in series with various alignment configurations under near‑field earthquakes
PublicationA major cause of local to total damages is related to structural pounding in a large number of past earthquakes. In general, these collisions take place as a result of differences in the dynamic characteristics of the colliding structures. To acquire a better perception of the behavior of structures, in this paper, three structures featuring different heights are modeled in series and with various configurations next to each other...
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Patryk Ziółkowski dr inż.
PeoplePatryk Ziolkowski is a graduate of the Faculty of Civil and Environmental Engineering at the Gdansk University of Technology, specializing in Building and Engineering Structures. He works as an Assistant Professor at the Department of Engineering Structures. He participated in international projects, including projects for the Ministry of Transportation of the State of Alabama (2015), he is also the winner of a grant from the Kosciuszko...
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Sub-national structures matter when evaluating physical activity promotion: Lessons from Germany
PublicationBackground Public policies are increasingly acknowledged as important part of promoting physical activity (PA). However, especially in states with sub-national administrative structures such as Germany, national and sub-national approaches differ considerably. In Germany, sport for all (SfA) promotion is mostly organized at sub-national level, which is usually not covered in national evaluations. Knowledge of these structures helps...
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Fast multi-objective design optimization of microwave and antenna structures using data-driven surrogates and domain segmentation
PublicationPurpose Strategies and algorithms for expedited design optimization of microwave and antenna structures in multi-objective setup are investigated. Design/methodology/approach Formulation of the multi-objective design problem oriented towards execution of the population-based metaheuristic algorithm within the segmented search space is investigated. Described algorithmic framework exploit variable fidelity modeling, physics- and...
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Isothermal calorimetry data for cement pastes containing pristine Bi2O3/Gd2O3 and silica-coated Bi2O3/Gd2O3 structures
Open Research DataCsv file containing raw calorimetric data determined up to 168 h (Tam Air 3 8-channel isothermal calorimeter) of cement pastes containing Bi2O3+Gd2O3 amd silica-coated Bi2O3-Gd2O3 structures. Sample designation in the .csv file is in line with sample designation in the manuscript associated with dataset.
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Improved selectivity compact band-stop filter with gosper fractal-shaped defected ground structures
PublicationA novel band-stop filter using Gosper fractal-shaped defected ground structures has been designed and manufactured. The improvement in the filter selectivity has been achieved by introducing a multiresonance fractal-shaped defect leading to a higher filter order, simultaneously maintaining its compact size. The experimental results prove the validity of proposed solution and its utility in novel miniaturized and severe requirement...
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Non-Linear Analysis of Structures Utilizing Load-Discretization of Stiffness Matrix Method with Coordinate Update
PublicationThis paper proposes a stiffness method based structural analysis algorithm for geometrically non-linear structures. In this study, the applied load on the joints has been discretized to a sequence of a few loadings applied. Each loading step produces incremental external nodal displacements, which are added to the corresponding coordinates to get a new geometrical shape of the structure. This process is iteratively repeated until...
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Closer look into the structures of tetrabutylammonium bromide–glycerol-based deep eutectic solvents and their mixtures with water
PublicationIn recent years, deep eutectic solvents (DES) and it’s mixture with water have become more and more attention as green solvents used in chemistry. However, there are only a few theoretical studies on the mechanisms of pure DES and DES-water complex formation. Therefore, the structural properties of tetrabutylammonium bromide–glycerol-based deep eutectic solvents and their mixtures with water have been investigated by means of Molecular...
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Image-based numerical modeling of the tensile deformation behavior and mechanical properties of additive manufactured Ti–6Al–4V diamond lattice structures
PublicationThis work concerns the numerical modeling of the deformation process and mechanical properties of structures obtained by the additive method laser power bed fusion (LPBF). The investigation uses diamond structures of Ti–6Al–4V titanium implantation alloy with various relative densities. To model the process of tensile deformation of the materials, geometric models were used, mapping the realistic shape of the examined structures....
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On Improved-Reliability Design Optimization of High-Frequency Structures Using Local Search Algorithms
PublicationThe role of numerical optimization has been continuously growing in the design of high-frequency structures, including microwave and antenna components. At the same time, accurate evaluation of electrical characteristics necessitates full-wave electromagnetic (EM) analysis, which is CPU intensive, especially for complex systems. As rigorous optimization routines involve repetitive EM simulations, the associated cost may be significant....
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Investigating the Effects of Geometrical Parameters of Re-Entrant Cells of Aluminum 7075-T651 Auxetic Structures on Fatigue Life
PublicationIn this study, the effects of two geometrical parameters of the re-entrant auxetic cells, namely, internal cell angle (θ) and H/L ratio in which H is the cell height, and L is the cell length, have been studied on the variations of Poisson’s ratio and fatigue life of Aluminum 7075-T6 auxetic structures. Five different values of both the H/L ratio and angle θ were selected. Numerical simulations and fatigue life predictions have...
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Kriging metamodels and design re‐utilization for fast parameter tuning of antenna structures
PublicationThe paper addresses the problem of computationally efficient electromagnetic (EM)‐driven design closure of antenna structures. The foundations of the presented approach are fast kriging interpolation metamodels, utilized for two purposes: (a) producing a good starting point for further parameter tuning, and (b) yielding a reasonable Jacobian matrix estimate to jump‐start the optimization procedure. The models are rendered using...
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Shaking table experimental study on the effectiveness of polymer bearings for seismic isolation of structures
PublicationSeismic isolation has been recognised to be a very effective way of protecting structures from damage during earthquakes. It allows us to extend the natural period of the structure and therefore avoid resonance with the ground motion. Moreover, by increasing damping in the isolation devices, more energy can be dissipated and thus the structural response can be further reduced. The aim of this paper is to show the results of the...
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A higher order transversely deformable shell-type spectral finite element for dynamic analysis of isotropic structures
PublicationThis paper deals with certain aspects related to the dynamic behaviour of isotropic shell-like structures analysed by the use of a higher order transversely deformable shell-type spectral finite element newly formulated and the approach known as the Time-domain Spectral Finite Element Method (TD-SFEM). Although recently this spectral approach is reported in the literature as a very powerful numerical tool used to solve various...
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Multi-layered mineral glass units used as viewport elements of underwater ship structures
PublicationIn the paper, Authors deals with viewport elements of underwater marine constructions. If a single-plate viewport constructions are considered, big thicknesses of the glass plate are required to resist the pressure. To build the viewports from the commercially accessible glass panes, multi-layered glass units are proposed in the paper. Numerical calculations are presented, summarized and compared with experimental tests. Focusing...
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Field investigations of stack ventilation in a residential building with multiple chimneys and tilted window in cold climate
PublicationArtykuł przedstawia wyniki pomiarów wykonanych w budynku mieszkalnym w północnej Polsce w zimnym klimacie podczas zimy i lata. Budynek zawierał kominy i uchylne okna. Pomierzono lokalne i wewnętrzne warunki klimatu oraz prędkości powietrza. Zaproponowano zmodyfikowany model uchylnych okien oparty na modelu wentylacji jednokierunkowej.
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Cold Start Emissions of Spark-Ignition Engines at Low Ambient Temperatures as an Air Quality Risk
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Cold atmospheric plasma-induced chemical vapor generation in trace element analysis by spectrometric methods
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Usage of Over-the-Counter and Herbal Products in Common Cold in Poland: Findings from Consumer Survey
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Rapid Yield Estimation and Optimization of Microwave Structures Exploiting Feature-Based Statistical Analysis
PublicationIn this paper, we propose a simple, yet reliable methodology to expediteyield estimation and optimization of microwave structures. In our approach,the analysis of the entire response of the structure at hand (e.g., $S$-parameters asa function of frequency) is replaced by response surface modeling of suitablyselected feature points. On the one hand, this is sufficient to determinewhether a design satisfies given performance specifications....
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Theoretical and experimental analysis of guided wave propagation in plate-like structures with sinusoidal thickness variations
PublicationGuided waves have attracted significant attention for non-destructive testing (NDT) and structural health monitoring (SHM) due to their ability to travel relatively long distances without significant energy loss combined with their sensitivity to even small defects. Therefore, they are commonly used in damage detection and localization applications. The main idea of incorporating guided waves in NDT and SHM is based on processing...
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Small signal spectra of complex capacitance obtained on organic heterojunction formed from copper phthalocyanine and perylene dye
PublicationPraca przedstawia małosygnałowe widma zespolonej pojemności otrzymane na strukturze z heterozłączem organicznym CuPc/Py-PTC w zakresie 25Hz-1MHz.
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Modeling and experimental investigation of the hydraulic jump in liquid film formed by an impinging two-phase air-water jet
PublicationPrzedstawiono model analityczny układu hydraulicznego powstałego na skutek uderzenia strugi dwufazowej wody i powietrza. Obliczenia porównano z badaniami eksperymentalnymi przeprowadzonymi na własnym stanowisku badawczym. Uzyskano zadowalającą zgodność.
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Preliminary Microbiological Tests of S-Carvone and Geraniol and Selected Derivatives of These Compounds That May Be Formed in the Processes of Isomerization and Oxidation
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Experimental validation of the theoretical analysis of heat transfer between a liquid layer formed by an impinging jet and a solid surface
PublicationPrzedstawiono wyniki badań eksperymentalnych wymiany ciepła między poziomą powierzchnią a przepływająca po niej warstwa cieczy utworzoną z napływającej strugi gazowo-cieczowej. Wyniki badań eksperymentalnych porównano z modelem teoretycznym zjawiska.
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Theoretical analysis of heat transfer between a liquid layer formed by an impinginf gas liquid jet AND a solid surface
PublicationHeat transfer phenomenon between a horizontal solid surface and a liquid layer created on a surface by an axisymmetrical liquid gas impinging jet has been analysed. The analytical treatment of the phenomenon is devoted to the area whose diameter is lower than the diameter of the hydraulic jump. W pracy przedstawiono teoretyczną analizę wymiany ciepła pomiędzy warstwą cieczy a stałą powierzchnią po której przepływa.
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Modelling and experimental investigation of the phenomenon of brekdown of the liquid layer formed by an impinging two-phase air-water jet
PublicationW pracy przedstawiono analizę teoretyczną i badania eksperymentalne badania zjawiska rozrywania warstwy cieczy powstałej z uderzającej strugi
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Zinc Oxide Nanoparticles Cytotoxicity and Release from Newly Formed PMMA–ZnO Nanocomposites Designed for Denture Bases
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Trace analyses of gaseous products formed during heat treatment of high stage H2SO4-GICs and expanded graphite
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Comprehensive stabilization of all streams of solid residues formed during sewage sludge thermal treatment – Case study
PublicationModern wastewater treatment plants are currently struggling with the problem of processing and ecological management of sewage sludge. Thermal utilization is a frequently used practice of excess sludge utilization especially in large wastewater treatment plants, which seems to be a quite promising concept. However, during thermal treatment, fractions of ashes and dusts are generated. Such wastes, especially the dust fraction, can...
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32P-postabeling detection of DNA adducts formed by 4-methyl-1-nitro-9-aminoacridine C-1748
PublicationWykazano zdolność do tworzenia przez nową pochodną 1-nitroakrydyny o symbolu C-1748, adduktów z DNA komórek nowotworowych oraz z DNA w systemie bezkomórkowym.
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Accurate Modeling of Antenna Structures by Means of Domain Confinement and Pyramidal Deep Neural Networks
PublicationThe importance of surrogate modeling techniques has been gradually increasing in the design of antenna structures over the recent years. Perhaps the most important reason is a high cost of full-wave electromagnetic (EM) analysis of antenna systems. Although imperative in ensuring evaluation reliability, it entails considerable computational expenses. These are especially pronounced when carrying out EM-driven design tasks such...
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Novel 1,2,3-Triazole Derivatives as Mimics of Steroidal System—Synthesis, Crystal Structures Determination, Hirshfeld Surfaces Analysis and Molecular Docking
PublicationHerein, we present the synthesis and crystal structures determination of five 4-(1-phenyl-1H-1,2,3-triazol-4-yl)phenol derivatives containing halogen atoms, 6a–e, which may be used as an excellent mimic of steroids in the drug development process. Good quality crystals obtained for all of the synthesized compounds allowed the analysis of their molecular structures. Subsequently, the determined crystal structures were used to calculate...
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Molecular structures of two E-azobenzocrown ethers
PublicationRentgenowska analiza strukturalna monokryształów posłużyła do scharakteryzowania struktury izomerów E dwóch azobenzokoron: 13- i 16-członowej. Oba związki krystalizują w układzie jednoskośnym. W komórce elementarnej, w każdym przypadku znajdują się dwie niezależne cząsteczki, różniące się konformacją, szczególnie łańcucha eterowego. Porównując konformacje ''wolnych'' makrocykli z konformacjami ich kompleksów z jonami metali wskazano,...
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Meander microstrip line with defected ground structures
PublicationW artykule omówiono koncepcję miniaturyzacji sekcji linii mikropaskowej poprzez modyfikację brzegu linii oraz warstwy metalizacji masy. W pracy zaprezentowano projekt oraz wyniki eksperymentu sprzęgacza gałęziowego skonstruowanego w oparciu o linię meandrową z zaburzoną warstwą metalizacji masy. Pomierzone charakterystyki transmisyjne potwierdzają atrakcyjność zastosowanych metod redukcji zajmowanej przez układ powierzchni. Osiągnięto...
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Propagation of elastic waves in shell-like structures
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Damage detection in riveted structures by laser measurements
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Two pseudopolymorphs of licl trimers with semicubane structures
PublicationCząsteczki tytułowych związków w ciele stałym przyjmują strukturę semikubanów - jest to pierwsza tego typu struktura dla solwatowanego chlorku litu. Jej budowę można opisać jako kuban [Li4Cl4(OPEt3)4], w którym jedna z cząsteczek LiCl została usunięta. Brak tej cząsteczki, a dokładniej mostkującego atomu Li, powoduje deformację struktury kubanu. Naroża zdeformowanego kubanu stanowią trzy atomy litu pochodzące z LiCl oraz cztery...
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Wavelet Analysis for Damage Identification in Composite Structures
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Wave propagation in plate structures for crack detection
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Parameterized diagnostic module implemented in FPGA structures
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Special Issue: “Non-Destructive Testing of Structures”
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Functionality stored in the structures of cyclodextrin–porphyrinoid systems
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Wavelet analysis for damage identification in composite structures
Publicationw pracy zaproponowano metodę analizy sygnalu opartą o transformatę falkową, pozwalajacą na identyfikcaje pęknięcia zmęczeniowego w jednowymiarowych elementach konstrukcyjnych wykonanych z materialow kompozytowych
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MAINTENANCE OF BASIC DRAINAGE STRUCTURES IN THE STARGARD DISTRICT
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Factors that strengthen and weaken the identity of the cluster structures
PublicationThe main aim of this paper is the application of "identity" to the issues related to "clustering process" and particularly - to the cooperation in the clusters and the cluster initiatives. The authors distinguish these factors that have the greatest influence on the formation and maintenance of identity in mentioned networks of cooperation.
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Modal FEM Analysis of Ferrite Resonant Structures
PublicationThe finite-element method (FEM) is applied for modal analysis of ferrite-loaded spherical resonators. To improve the efficiency of the numerical calculations, the body-of-revolution (BOR) technique is utilized. Due to the frequency-dependent ferrite permeability, FEM leads to a nonlinear eigenvalue problem that is challenging to solve. To this end, Beyn’s method is proposed. The effectiveness of the proposed approach is confirmed...
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Impedance measurements of coating properties on bridge structures
PublicationPomiary impedancyjne pozwalają na prostą ocenę właściwości ochronnych powłok ochronnych i wykładzin. Pomiary stosuje się w celu porównania powłok, monitorowania ich właściwości i oceny mechanizmu działania. Metodyka jest z powodzeniem stosowana w pomiarach laboratoryjnych. Pomiary terenowe są bardziej skomplikowane ponieważ wymagają w pełni kontrolowanych komputerowo przyrządów, kontroli warunków pogodowych oraz wielu innych parametrów...
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Wave propagation in plate structures for crack detection.
PublicationW pracy przedstawiono analizę propagacji fali poprzecznej w płycie z pęknięciem. Do modelowania zagadnienia zastosowano metodę elementów spektralnych.
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Developing Polycentricity to Shape Resilient Metropolitan Structures: The Case of the Gdansk–Gdynia–Sopot Metropolitan Area
PublicationMaking the metropolitan area resilient, in many cases, calls for amending its spatial structures. This may take various forms, including both reshaping the metropolitan core and redeveloping the entire regional network of cities and centres, making them part of a coherent structure. The latter strategy is associated with reinforcing secondary urban centres as well as shaping new connections between them. In this case, the term...