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Search results for: POUNDING, TIMBER FRAME BUILDINGS, EARTHQUAKES, SEISMIC, FEM, NUMERCIAL MODELING, GROUND MOTIONS
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Design-Oriented Two-Stage Surrogate Modeling of Miniaturized Microstrip Circuits with Dimensionality Reduction
PublicationContemporary microwave design heavily relies on full-wave electromagnetic (EM) simulation tools. This is especially the case for miniaturized devices where EM cross-coupling effects cannot be adequately accounted for using equivalent network models. Unfortunately, EM analysis incurs considerable computational expenses, which becomes a bottleneck whenever multiple evaluations are required. Common simulation-based design tasks include...
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Improved Modeling of Microwave Structures Using Performance-Driven Fully-Connected Regression Surrogate
PublicationFast replacement models (or surrogates) have been widely applied in the recent years to accelerate simulation-driven design procedures in microwave engineering. The fundamental reason is a considerable—and often prohibitive—CPU cost of massive full-wave electromagnetic (EM) analyses related to solving common tasks such as parametric optimization or uncertainty quantification. The most popular class of surrogates are data-driven...
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On Inadequacy of Sequential Design of Experiments for Performance-Driven Surrogate Modeling of Antenna Input Characteristics
PublicationDesign of contemporary antennas necessarily involves electromagnetic (EM) simulation tools. Their employment is imperative to ensure evaluation reliability but also to carry out the design process itself, especially, the adjustment of antenna dimensions. For the latter, traditionally used parameter sweeping is more and more often replaced by rigorous numerical optimization, which entails considerable computational expenses, sometimes...
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The Characterization of Ground Raspberry Seeds and the Physiological Response to Supplementation in Hypertensive and Normotensive Rats
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Never ending story: a lesson in using sampling efficiency methods with ground beetles
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Effect of extraction method on the antioxidative activity of ground elder (Aegopodium podagraria L.)
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Characterization and properties of LDPE/(ground tire rubber)/crosslinked butyl rubber blends
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Spatio-Temporal Variation in Predation on Artificial Ground Nests: A 12-Year Experiment
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Velocity measurement using the fdoa method in ground-based radio navigation system
PublicationVelocity is one of the main navigation parameters of the moving objects. However some systems of position estimation using radio wave measurements cannot provide velocity data due to limitation of their performance. In this paper a velocity measurement method for DS-CDMA radio navigation system is proposed, which doesn’t require full synchronization of reference stations carrier frequencies. The article presents basics of FDOA...
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Numerical analysis of a test embankment on soft ground using an anisotropic model with destructuration
PublicationPrzeprowadzono analizę numeryczną konsolidacji podłoża słabonośnego pod obciążeniem próbnego nasypu drogowego metodą elementów skończonych. Zachowanie się gruntu słabonośnego zamodelowano przy użyciu nowego modelu konstytutywnego typu multi-laminate uwzględniającego anizotropię wytrzymałości oraz zjawisko destrukturyzacji. Wyniki obliczeń porównano z pomiarami polowymi.
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Analysis of coupled coplanar waveguide with ideal bonding wires between ground conductors
PublicationPrzedstawiono zmodyfikowaną analizę sprzężonych linii koplanarnych prowadzącą do uproszczenia procesu modelowania struktur wieloprzewodowych zawierających poprzecznie ułożone względem kierunku propagacji fali mostki dla wyrównania potencjałów na odseparowanych przestrzennie przewodach. Wyniki analizy teoretycznej zweryfikowano doświadczalnie uzyskując potwierdzenie poprawności zastosowanego podejścia.
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Study of pozzolanic action of ground waste expanded perlite by means of thermal methods
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Influence of feed rate on the granularity and homogenity of oak sawdust obtained during the sawing process on the frame sawing machine PRW15M
PublicationOpisano wpływ prędkości posuwu na skład granulometryczny i jednorodność trocin dębowych otrzymanych podczas procesu przecinania na pilarce ramowej PRW15M. Wykazano, że otrzymane trociny mogą być wykorzystane w produkcji produktów drewnopochodnych w ilości 75% dla posuwu 0.36 m/min i 82% przy posuwie 1.67 m/min. Pozostałe trociny stanowią odpad.
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Sawdust size distribution analysis of thermally modified and unmodified oak wood sawed on the frame sawing machine PRW15-M
PublicationW pracy przedstawiono wyniki analizy granulometrycznej składu wiórów drewna dębowego niemodyfikowanego i modyfikowanego termicznie uzyskanych podczas piłowania na pilarce ramowej PRW15-M z prędkością posuwu 1.67 mmin-1. Otrzymane trociny termicznie modyfikowanego drewna dębowego składają się z wiórów o ziarnistości w przedziale od 44.7 mm do 4.6 mm, podczas gdy dla drewna niemodyfikowanego zaobserwowano zmiany ziarnistości w granicach...
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Vibrational inelastic electron-H2 scattering revisited: numerically converged coupled channels space frame calculations with model interaction
PublicationZderzeniowe wzbudzenie niższych oscylacyjnych poziomów molekuły H2 (^1Σ^+,g) przez elektrony o niskiej energii. Obliczenia wykonano przy użyciu empirycznego modelowego potencjału oraz przez rozwiązanie równania rozpraszania dwukanałowego w układzie współrzędnych, związanych z molekułą.
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Chosen aspects of skeletal system modeling: Numerical solid and shell models of femur part
PublicationThe purpose of this paper is to present a new method of femur part modeling by using the finite element method. This method treats a femur part as a system composed of cortical and trabecular bone. For the purpose of determining a proper shape of femur part model there were created three models: a) the first one describes a femur part as a solid structure; b) the second one describes a femur part as a connection of cortical bone...
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Multiplication Analysis of the Cause, Form and Extent of Damage to Buildings in Areas with Mining Impact
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The methodology of technical due diligence report preparation for an office, residential and industrial buildings
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An Innovative Decision Support System to Improve the Energy Efficiency of Buildings in Urban Areas
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STUDIES ON THE USE OF TERRESTRIAL LASER SCANNING IN THE MAINTENANCE OF BUILDINGS BELONGING TO THE CULTURAL HERITAGE
PublicationWithin the frames of the use of terrestrial laser scanning we find numerous examples of registration of building facilities, including also historical and valuable in their culture. In the case presented in this paper, at the root of the problem there is a preservation of the historic blacksmith’s forge located in Gdansk Orunia. The facility dating from the early nineteenth century was intended to repair involving the complete...
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Studies on the use of terrestrial laser scanning in the maintenance of buildings belonging to the cultural heritage
PublicationWithin the frames of the use of terrestrial laser scanning we find numerous examples of registration of building facilities, including also historical and valuable in their culture. In the case presented in this paper, at the root of the problem there is a preservation of the historic blacksmith's forge located in Gdansk Orunia. The facility dating from the early nineteenth century was intended to repair involving the complete...
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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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Numerical investigations of effect of indoor air quality on thermal comfort in residential buildings.
PublicationArtykuł przedstawia wyniki numeryczne MES odnośnie wpływu koncentracji CO2 w lokalnej strefie powietrza w budynkach mieszkalnych naturalnie wentylowanych na zachowanie mieszkańców. Obliczenia wykonano w 2 wymiarach. Zbadano wpływ położenia mieszkańców i prędkości wchodzącego powietrza.
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Modeling Methodologies for the Environment EE Msc sem. II r.a. 23/24
e-Learning CoursesZrozumienie procesów które mają wpływ na migrację i przemiany zanieczyszczeń w środowisku (ze szczególnym uwzględnieniem wód powierzchniowych). Zajęcia dotyczą podstaw i zasad budowy modeli jakości wody oraz służą pokazaniu jak te modele mogą być wykorzystywane do rozwiązywania problemów w inżynierii środowiska.
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Modeling lignin extraction with ionic liquids using machine learning approach
PublicationLignin, next to cellulose, is the second most common natural biopolymer on Earth, containing a third of the organic carbon in the biosphere. For many years, lignin was perceived as waste when obtaining cellulose and hemicellulose and used as a biofuel for the production of bioenergy. However, recently, lignin has been considered a renewable raw material for the production of chemicals and materials to replace petrochemical resources....
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Achieving Efficient and Stable Deammonification at Low Temperatures—Experimental and Modeling Studies
PublicationThe short-term effects of temperature on deammonification sludge were evaluated in a laboratory-scale sequencing batch reactor (SBR). Mathematical modeling was used for further evaluations of different intermittent aeration strategies for achieving high and stable deammonification performance at decreasing temperatures. As for the biomass cultivated at high temperatures (e.g., 30 C), a higher temperature dependency (the adjusted...
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Modeling the impact of discretizing rotor angular position on computation of field-oriented current components in high speed electric drives
PublicationModern drives consist of alternating current electric motors, and the field-oriented control (FOC) of such motors enables fast, precise, and robust regulation of a drive's mechanical variables such as torque, speed, and position. The control algorithm, implemented in a microprocessor, requires feedback from motor currents, and the quality of this feedback is essential to a drive's control properties. Motor phase currents are sampled...
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Weather Hazard Avoidance in Modeling Safety of Motor-Driven Ship for Multicriteria Weather Routing
PublicationWeather routing methods find the most suitable ocean?s route for a vessel, taking into account changeable weather conditions and navigational constraints. In the multicriteria approach based on the evolutionary SPEA algorithm one is able to consider a few constrained criteria simultaneously. The approach applied for a ship with hybrid propulsions has already been presented by one of the authors on previous TransNav?2009. This time...
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Modeling of Surface Roughness in Honing Processes by UsingFuzzy Artificial Neural Networks
PublicationHoning processes are abrasive machining processes which are commonly employed to improve the surface of manufactured parts such as hydraulic or combustion engine cylinders. These processes can be employed to obtain a cross-hatched pattern on the internal surfaces of cylinders. In this present study, fuzzy artificial neural networks are employed for modeling surface roughness parameters obtained in finishing honing operations. As...
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Rapid Design of 3D Reflectarray Antennas by Inverse Surrogate Modeling and Regularization
PublicationReflectarrays (RAs) exhibit important advantages over conventional antenna arrays, especially in terms of realizing pencil-beam patterns without the employment of the feeding networks. Unfortunately, microstrip RA implementations feature narrow bandwidths, and are severely affected by losses. A considerably improved performance can be achieved for RAs involving grounded dielectric layers, which are also easy to manufacture using...
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Modeling N2O behavior during denitrification with different carbon sources and electron acceptors
PublicationA mathematical model was developed for identification of the most important mechanism leading to nitrous oxide (N2O) accumulation in denitrifying activated sludge systems. The activated sludge model No. 2d (ASM2d) was extended to include intermediate three steps of the denitrification process. The formation and accumulation of nitric oxide (NO) was assumed to be very low in the performed laboratory experiments. These experiments...
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Modeling by finite element methods of impact of erosion on frequency of normal modes of L-0 blade
PublicationAfter some time of exploitation steam turbine rotors blades in energetic industry they are being eroded and also their frequency of normal modes is changed. Those changes can cause to unwanted shift of blades normal mode frequencies. It is necessary to find quick method of rating changes of frequency in connection of mass loss due erosion. The evaluation of this dependence was made by finite element modeling method using HyperWorks...
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Surrogate modeling of impedance matching transformers by means of variable‐fidelity electromagnetic simulations and nested cokriging
PublicationAccurate performance evaluation of microwave components can be carried out using full‐wave electromagnetic (EM) simulation tools, routinely employed for circuit verification but also in the design process itself. Unfortunately, the computational cost of EM‐driven design may be high. This is especially pertinent to tasks entailing considerable number of simulations (eg, parametric optimization, statistical analysis). A possible...
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Uniform sampling in constrained domains for low-cost surrogate modeling of antenna input characteristics
PublicationIn this letter, a design of experiments technique that permits uniform sampling in constrained domains is proposed. The discussed method is applied to generate training data for construction of fast replacement models (surrogates) of antenna input characteristics. The modeling process is design-oriented with the surrogate domain spanned by a set of reference designs optimized with respect to the performance figures and/or operating...
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Computational Analysis of Transformational Organisational Change with Focus on Organisational Culture and Organisational Learning: An Adaptive Dynamical Systems Modeling Approach
PublicationTransformative Organisational Change becomes more and more significant both practically and academically, especially in the context of organisational culture and learning. However computational modeling and formalization of organisational change and learning processes are still largely unexplored. This chapter aims to provide an adaptive network model of transformative organisational change and translate a selection of organisational...
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Curing characteristics of ground tire rubber modified by commercial additives
Open Research DataThe presented results show the influence of commercially available bitumen and transoctenamer rubber (TOR) on the curing behavior of GTR treated by a peroxide. Samples were prepared using a two-roll mill– all in the same manner. After 24 hours of aging at ambient conditions, they were submitted to the curing analysis via Rheometer Monsanto 100S. The...
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Expedited Acquisition of Database Designs for Reduced-Cost Performance-Driven Modeling and Rapid Dimension Scaling of Antenna Structures
PublicationFast replacement models have been playing an increasing role in high-frequency electronics, including the design of antenna structures. Their role is to improve computational efficiency of the procedures that normally entail large numbers of expensive full-wave electromagnetic (EM) simulations, e.g., parametric optimization or uncertainty quantification. Recently introduced performance-driven modeling methods, such as the nested...
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Numerical analysis by FEM and analytical study of the dynamic thermal behavior of hollow bricks with different cavity concentration
PublicationThis paper presents the investigation results on the influence of the cavity concentration in hollow bricks on static and dynamic thermal parameters: a time lag, a decrement factor, an equivalent thermal diffusivity (ETD) and an equivalent thermal conductivity (ETC). The dynamic thermal behavior of hollow bricks is studied with an optimized cavity shape to reduce the intensity of radiation and convective heat exchange. The thermal...
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Finite element method (FEM) implementation in some chosen areas in dental tytanium-ceramic crown design
PublicationAnaliza rozkładu naprężeń wykazała, że szczególnie duże spiętrzenia naprężeń powstają w częściach przyszyjkowych tytanowo-ceramicznej korony stomatologicznej. W przyszyjkowej części modelu występują największe naprężenia rozciągające, szczególnie niebezpieczne dla ceramiki nieodpornej na tego typu obciążenia. Mogą one stanowić przyczynę spękania i odprysków w części przyszyjkowej korony. Wyniki symulacji komputerowej metodą MES...
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A FEM membrane model of human fascia-synthetic implant system in a case of a stiff ventral hernia orifice
PublicationPraca prezdstawia model matematyczny układu tkanka ludzka - implant syntetyczny w postaci tzw. siatki w leczeniu przepuklin brzusznych. Implant jest tu moelowany jako struktura membranowa. Ocena wpływu danych materiałowych oraz wstępnego napięcia na zachowanie pracującej membrany po implantacji została przedstawiona na podstawie analizy wrażliwości. Pracę podsumowują pewne wskazówki dla chirurgów implantujących siatki.
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Application of 3D Digital Image Correlation for Development and Validation of FEM Model of Self-Supporting Arch Structures
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Nonlinear FEM 2D failure onset prediction of composite shells based on 6-parameter shell theory
PublicationWithin the framework of the nonlinear 6-parameter shell theory with the drilling rotation and asymmetric stress measures, the modifications of Tsai-Wu and Hashin laminate failure initiation criteria are proposed. These improvements enable to perform first ply failure estimations taking into account the non-symmetric stress measures. In order to check the validity of the proposed criteria, finite element analyses are performed with...
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Design of Structure of Tension Leg Platform for 6 MW Offshore Wind Turbine Based On Fem Analysis
PublicationThe article presents the calculation and design stages of the TLP platform serving as a supporting construction of a 6 MW offshore wind turbine. This platform is designed to anchor at sea at a depth of 60 m. The authors presented the method of parameterization and optimization of the hull geometry. For the two selected geometry variants, the load and motion calculations of the platform subjected to wind, wave and current under...
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Numerical analysis by FEM and analytical study of the dynamic thermal behavior of hollow bricks with different cavity concentration
PublicationThis paper presents the investigation results on the influence of the cavity concentration in hollow bricks on static and dynamic thermal parameters: a time lag, a decrement factor, an equivalent thermal diffusivity (ETD) and an equivalent thermal conductivity (ETC). The dynamic thermal behavior of hollow bricks is studied with an optimized cavity shape to reduce the intensity of radiation and convective heat exchange. The thermal...
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Modeling two phase flow in large scale fractured porous media with an extended multiple interacting continua method
PublicationWe present a two phase flow conceptual model, the corresponding simulator (2pMINC) and a workflow for large-scale fractured reservoirs, based on a continuum fracture approach which uses the multiple interacting continua (MINC) method complemented with an improved upscaling technique. The complex transient behavior of the flow processes in fractured porous media is captured by subgridding the coarse blocks in nested volume elements...
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Computer modeling and testing of structural metamaterials
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Molecular Modeling of Meta II Rhodopsin
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Modeling of nonlinear generation in a bubble layer
PublicationPraca prezentuje numeryczne podejście do zagadnienia liniowego i nieliniowego rozpraszania w warstwie z pęcherzykami. Badania numeryczne niekoherentnego rozpraszania wykonano stosując metodę Monte Carlo. Propagację i wsteczne rozpraszanie sygnałów badano w oparciu o równanie Rayleigha-Plesseta.
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The CFD modeling in bioreactor tracer studies
PublicationW artykule zaprezentowano badania traserowe w bioreaktorach z osadem czynnym. Przedstawiono efekty działania procesu dyspersji na podstawie obliczonych podłużnych profili koncentracji znacznika w komorach osadu czynnego zlokalizowanych na Oczyszczalni Ścieków "Wschód" w Gdańsku. W ramach badań wykonano symulację przepływu substancji nieaktywnej (bazując na pomierzonych profilach stężenia znacznika) stosując jednowymiarowe równanie...
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Modeling Dynamics of Autonomous Underwater Vehicle.
PublicationArtykuł dotyczy budowy modelu autonomicznego pojazdu podwodnego do celów syntezy układu sterowania pojazdem. Rozważany pojazd ma długośc ok. 1 m i 30 cm średnicy. Wyposażony jest w 5 pędników, które pozwalają na sterowanie w pięciu stopniach swobody. Do badań wykorzystano model o 4 stopniach swobody. Dokonano identyfikacji parametrycznej modelu. Model zrealizowano w środowisku programowym Matlab/Simulink.