Wyniki wyszukiwania dla: MODELING APPLICATIONS
-
Nonlinear planar modeling of massive taut strings travelled by a force-driven point-mass
PublikacjaThe planar response of horizontal massive taut strings, travelled by a heavy point-mass, either driven by an assigned force, or moving with an assigned law, is studied. A kinematically exact model is derived for the free boundary problem via a variational approach, accounting for the singularity in the slope of the deflected string. Reactive forces exchanged between the point-mass and the string are taken into account via Lagrange...
-
MATHEMATICAL MODELING OF FLOOD MANAGEMENT SYSTEM IN THE CITY OF GDAŃSK, ORUŃSKI STREAM CASE STUDY
PublikacjaAim of the study This study analyses the efficiency of flood protection in a small urban catchment, based on a system of small reservoirs. Material and methods To assess the flood routing and surge reduction, a mathematical model of the river catchment was implemented. This was a lumped hydrological model, based on the SCS-CN method. Channel routing was performed, using kinematic wave equation. The sub-catchments have been determined...
-
On Inadequacy of Sequential Design of Experiments for Performance-Driven Surrogate Modeling of Antenna Input Characteristics
PublikacjaDesign 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...
-
Design-Oriented Two-Stage Surrogate Modeling of Miniaturized Microstrip Circuits with Dimensionality Reduction
PublikacjaContemporary 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...
-
Reliable Surrogate Modeling of Antenna Input Characteristics by Means of Domain Confinement and Principal Components
PublikacjaA reliable design of contemporary antenna structures necessarily involves full-wave electromagnetic (EM) analysis which is the only tool capable of accounting, for example, for element coupling or the effects of connectors. As EM simulations tend to be CPU-intensive, surrogate modeling allows for relieving the computational overhead of design tasks that require numerous analyses, for example, parametric optimization or uncertainty...
-
Editorial for the special issue on advances in forward and inverse surrogate modeling for high-frequency design
PublikacjaThe design of modern‐day high‐frequency devices and circuits, including microwave/RF, antenna and photonic components, historically has relied on full‐wave electromagnetic (EM) simulation tools. Initially used for design verification, EM simulations are nowadays used in the design process itself, for example, for finding optimum values of geometry and/or material parameters of the structures of interest. In a growing number of...
-
Interatomic potential suitable for the modeling of penta-graphene: Molecular statics/molecular dynamics studies
PublikacjaWe test the potentials available for elemental carbon, with the scope to choose the potential suitable for the modeling of penta-graphene, the latest two dimensional carbon allotrope. By using molecular statics and molecular dynamics simulations we show that there is only one potential e namely the Tersoff-type potential proposed by Erhart and Albe in 2005 e which is able to correctly describe all the important features of penta-graphene....
-
Free surface flow modeling in numerical estimation of flood risk zones: a case study
PublikacjaNa przykładzie doliny Wisły w Warszawie przedstawiono metodę wyznaczenia stref zagrożenia powodziowego. Symulowana numerycznie powódź wywołana została potencjalnym przerwaniem obwałowania rzeki w okolicach Saskiej Kępy. Do obliczeń zastosowano opracowany w Katedrze Hydrotechniki Wydziału Inżynierii Lądowej i Środowiska Politechniki Gdańskiej model dwuwymiarowego, płaskiego przepływu wody ze swobodną powierzchnią.
-
Modeling of effect of plastic deformation on Barkhausen noise and magnetoacoustic emission in iron with 2% silicon
PublikacjaW modelowaniu zaadaptowano model Alessandro-Beatrice-Bertotti-Montorsi dla opisu ruchu granic nie-180 stopniowych oraz model Jiles-Atherton dla opisu wpływu plastycznej deformacji na natężenie efektu Barkhausena oraz emisji magnetoakustcznej.
-
Accurate modeling of layout parasitic to forecast EMI emitted from a DC-DC converter.
PublikacjaThis paper illustrates how to account for all parasitic due to the layout of a power converter (inductive and capacitive), in order to forecast electromagnetic interferences (EMI). The method is generic, and is validated here in the simple example of a DC-DC converter, realized on different technologies: insulated metal substrate (IMS), printed circuit board (PCB). In addition, several layouts aspects will be investigated. Conclusions...
-
Modelowanie hydraulicznych skutków katastrofy zapory wodnej. Modeling of dam-break water flow
PublikacjaPrzedstawiono numeryczne rozwiązanie równań przepływu wody płytkiej wywołanego katastrofą zapory wodnej. Przestrzenną dyskretyzację równań wykonano metodą objętości skończonych. Metodę zastosowano do prognostycznych obliczeń propagacji fali wezbraniowej wywołanej katastrofą zapory wodnej w dolinie rzeki Toce. Wyniki obliczeń porównano z dostępnymi (obcymi) pomiarami wykonanymi na fizycznym modelu doliny. Uzyskano zadowalającą...
-
An advanced tool integrating failure and sensitivity analysis into novel modeling of the stormwater flood volume
PublikacjaAn innovative tool for modeling the specific flood volume was presented that can be applied to assess the need for stormwater network modernization as well as for advanced flood risk assessment. Field measurements for a catchment area in Kielce, Poland, were used to apply the model and demonstrate its usefulness. This model extends the capability of recently developed statistical and machine learning hydrodynamic models developed...
-
Weather Hazard Avoidance in Modeling Safety of Motor-Driven Ship for Multicriteria Weather Routing
PublikacjaWeather 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...
-
The protocol for using elastic wall model in modeling blood flow within human artery
PublikacjaMedical diagnostic tools will play a major role in the future for an effective patient treatment and reduction their mortality, related to the cardiovascular system diseases (CVDs). There is an urgent need for developing diagnostic procedure to be robust, reliable, accurate and efficient, in the framework of a paradigm shift. Application of numerical techniques is seen as a perspective tool for such purpose. Nevertheless, existing...
-
A new approach to modeling of selected human respiratory system diseases, directed to computer simulations
PublikacjaThis paper presents a new versatile approach to model severe human respiratory diseases via computer simulation. The proposed approach enables one to predict the time histories of various diseases via information accessible in medical publications. This knowledge is useful to bioengineers involved in the design and construction of medical devices that are employed for monitoring of respiratory condition. The approach provides the...
-
Geospatial Modeling of the Tombolo Phenomenon in Sopot using Integrated Geodetic and Hydrographic Measurement Methods
Publikacja -
Comparative modeling of shear zone patterns in granular bodies with finite and discrete element method
PublikacjaW artykule przedstawiono wyniki numeryczne naporu piasku na ściankę szczelną. Obliczenia wykonano stosując metodę elementów dyskretnych i skończonych na bazie mikropolarnego hipoplastycznego prawa materiałowego. Porównanie obu podejść wykonano na poziomie makro i mikro. Wyniki numeryczne porównano także z wynikami doświadczalnymi.
-
Evaluation of open drone map toolkit for geodetic grade aerial drone mapping – case study
PublikacjaAn open source tool’s popularity has increased considerably, as well as micro aerial vehicles (MAV) technologies based on open source hardware. An open source software and hardware delivers a wide variety of applications and technology. The world’s most successful open source projects have their roots in the academy, and now its participation includes a wide variety of academic programs and research. Based on open source technology,...
-
On Applications of Elements Modelled by Fractional Derivatives in Circuit Theory
PublikacjaIn this paper, concepts of fractional-order (FO) derivatives are reviewed and discussed with regard to element models applied in the circuit theory. The properties of FO derivatives required for the circuit-level modeling are formulated. Potential problems related to the generalization of transmission-line equations with the use of FO derivatives are presented. It is demonstrated that some formulations of FO derivatives have limited...
-
Numerical Modeling of Steel Surface Hardening in the Process of High Energy Heating by High Frequency Currents
Publikacja -
Count Data Modeling About Relationship Between Dubai Housing Sales Transactions and Financial Indicators
Publikacja -
The Impact of Lightning Flashes and Sprites on the Earth’s Global Electric Circuit: An Overview of Recent Modeling Results
Publikacja -
Modeling hydrolysis of slowly biodegradable organic compounds in biological nutrient removal activated sludge systems
PublikacjaHydrolysis is an important process in biological wastewater treatment and is known to be the ratelimiting step in organic carbon removal from municipal or industrial wastewater. The influence of the readily biodegradable chemical oxygen demand fraction in biological wastewater treatment systems has been extensively investigated, but little is known about the effects of slowly biodegradable substrate (XS) on denitrification and...
-
Molecular modeling and evaluation of novel dibenzopyrrole derivatives as telomerase inhibitors and potential drug for cancer therapy
PublikacjaDuring previous years, many studies on synthesis, as well as on anti-tumor, anti-inflammatory and anti-bacterial activities of the pyrazole derivatives have been described. Certain pyrazole derivatives exhibit important pharmacological activities and have proved to be useful template in drug research. Considering importance of pyrazole template, in current work the series of novel inhibitors were designed by replacing central...
-
Modelowanie asymetrycznego procesu walcowania blach bimetalowych = The modeling of asymetrical rolling process of bimetallic plate
PublikacjaW pracy rozważano problem płynięcia plastycznego bimetalowego pasma podczas asymetrycznego procesu walcowania blach bimetalowych. Asymetrię procesu uzyskano w wyniku wprowadzenia różnic w wartościach sił tarcia na powierzchniach styku pasma z poszczególnymi walcami.
-
Modeling by finite element methods of impact of erosion on frequency of normal modes of L-0 blade
PublikacjaAfter 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...
-
Modeling of Common Mode Currents Induced by Motor Cable in Converter Fed AC Motor Drives
PublikacjaInvestigation of conducted EMI generation in AC motor fed by pulse width modulated frequency converters requires to consider parasitic capacitances in converters, motor windings and feeding cables to be taken into account. Motor voltage transients and related common mode currents are significantly correlated with resonance effects occurring in load circuits. An analysis of frequency converter load impedance-frequency characteristics...
-
Molecular dynamics simulation of human neurohypophyseal hormone receptors complexed with oxytocin—modeling of an activated state
Publikacja -
Modeling of the L and M x-ray line structures for tungsten in high-temperature tokamak plasmas
Publikacja -
Comparison of single best artificial neural network and neural network ensemble in modeling of palladium microextraction
Publikacja -
Modeling the photodynamic effect in 2D versus 3D cell culture under normoxic and hypoxic conditions
Publikacja -
Brassica Napus Florescence Modeling Based on Modified Vegetation Index Using Sentinel-2 Imagery
Publikacja -
Fabrication and Characterization of Flexible Medical-Grade TPU Filament for Fused Deposition Modeling 3DP Technology
Publikacja -
Editorial: smart modeling support for managing complexities and dynamics of knowledge-based systems-part 1
Publikacja -
Design-oriented modeling of antenna structures by means of two-level kriging with explicit dimensionality reduction
PublikacjaThe employment of full-wave electromagnetic (EM) analysis is a practical necessity in the design of contemporary antenna structures. This is because simpler models are generally not available or of limited accuracy. At the same time, EM-based design is computationally expensive. Consequently, the ways of accelerating tasks such as parametric optimization or uncertainty quantification have to be sought. A possible workaround that...
-
In-Out Surface Modification of Halloysite Nanotubes (HNTs) for Excellent Cure of Epoxy: Chemistry and Kinetics Modeling
PublikacjaIn-out surface modification of halloysite nanotubes (HNTs) has been successfully performed by taking advantage of 8-hydroxyquinolines in the lumen of HNTs and precisely synthesized aniline oligomers (AO) of different lengths (tri- and pentamer) anchored on the external surface of the HNTs. Several analyses, including FTIR, H-NMR, TGA, UV-visible spectroscopy, and SEM, were used to establish the nature of the HNTs’ surface engineering....
-
Adaptive Method for Modeling of Temporal Dependencies between Fields of Vision in Multi-Camera Surveillance Systems
PublikacjaA method of modeling the time of object transition between given pairs of cameras based on the Gaussian Mixture Model (GMM) is proposed in this article. Temporal dependencies modeling is a part of object re-identification based on the multi-camera experimental framework. The previously utilized Expectation-Maximization (EM) approach, requiring setting the number of mixtures arbitrarily as an input parameter, was extended with the...
-
Modeling process of planning finished product sales volumes at industrial enterprises in modern economic conditions
PublikacjaThis article presents improving the existing system of planning finished products sales volumes. The influencing factors of the sales volumes in modern economic conditions have been determined: falling world oil prices, the reduction of pipe consumption in the domestic market, the global pandemic. The algorithm of planning finished products sales volumes has been constructed. Calculations based on the Holt forecasting method has...
-
Spectral reflectance and transmission modeling of multi-cavity Fabry-Pérot interferometer with ZnO thin films
PublikacjaIn this paper spectral reflectance and transmission of a low-coherence fiber-optic Fabry-Pérot interferometer with thin ZnO layers is analyzed using a multi-cavity approach. In the investigated setup two standard single-mode optical fibers (SMF-28) with thin ZnO films deposited on their end-faces form an extrinsic Fabry-Pérot interferometer with air cavity. Calculations of the spectral response of the interferometer were performed...
-
Cost-Efficient Bi-Layer Modeling of Antenna Input Characteristics Using Gradient Kriging Surrogates
PublikacjaOver the recent years, surrogate modeling has been playing an increasing role in the design of antenna structures. The main incentive is to mitigate the issues related to high cost of electromagnetic (EM)-based procedures. Among the various techniques, approximation surrogates are the most popular ones due to their flexibility and easy access. Notwithstanding, data-driven modeling of antenna characteristics is associated with serious...
-
Fabrication and Characterization of Flexible Medical-Grade TPU Filament for Fused Deposition Modeling 3DP Technology
PublikacjaThe possibility of using additive manufacturing (AM) in the medicine area has created new opportunities in health care. This has contributed to a sharp increase in demand for 3D printers, their systems and materials that are adapted to strict medical requirements. We described herein a medical-grade thermoplastic polyurethane (S-TPU) which was developed and then formed into a filament for Fused Deposition Modeling (FDM) 3D printers...
-
Numerical modeling and experimental validation of full-scale segment to support design of novel GFRP footbridge
PublikacjaThe paper contains analysis of full-scaled three meters long segment of a novel composite footbridge. Both numerical modeling and experimental validation were performed. Analyzed object is a shell type sandwich channel-like structure made of composite sandwich with GFRP laminates as a skin and PET foam as a core. Several static load schemes were performed including vertical and horizontal forces. In FEM analysis multilayered laminate...
-
BUILDING INFORMATION MODELING - ANALIZA ZAKRESU I STANU IMPLEMENTACJI W POLSKIEJ BRANŻY BUDOWLANEJ
PublikacjaProblematyka BIM (Building Information Modeling) jest obecnie tematem wielu publikacji naukowych, ale także przedmiotem działań podejmowanych przez uczestników szeroko pojętego procesu budowlanego. Liczne zalety i szanse płynące ze stosowania technologii BIM w kolejnych etapach cyklu życia obiektu budowlanego, należy rozpatrywać z punktu widzenia inwestora/zamawiającego, architekta, projektanta konstrukcji i instalacji, dewelopera,...
-
Numerical Modeling of Cone Penetration Test in Slightly Overconsolidated Clay with Arbitrary Lagrangian-Eulerian Formulation
PublikacjaIn this paper the results of the cone penetration test (CPT) modeling with the arbitrary Lagrangian-Eulerian (ALE) formulation provided by Abaqus software package have been presented. The study compares the cone resistance and sleeve friction obtained in numerical analysis with values measured in soundings performed in the uniform layer of clayey soil in the Koszalin area. The clay layer was found to be slightly overconsolidated...
-
Mathematical Modeling of Ice Thrusting on the Shore of the Vistula Lagoon (Baltic Sea) and the Proposed Artificial Island
PublikacjaCoastal lagoons are inland and shallow water bodies, separated from the ocean by a barrier. In cold regions, ice phenomena in shallow water coastal lagoons occur every winter season. Ice is predominantly formed on the surface due to density stratification and surface cooling. The ice dynamics in such areas are dominantly affected by winds. Water dynamics also cause ice movement, but due to the large areal scale of lagoons, the...
-
Rigid finite elements and multibody modeling in analyses of a robot shaped elastic/plastic deformations of a beam
PublikacjaDynamics analysis of a system composed of a parallel manipulator and of an elastic beam is presented in the paper. Classic 3RRR parallel manipulator is considered and used to deform the beam. Elasto-plastic deformations are investigated. Rigid-finite-elements technique is employed to deal with dynamics of the beam. A multibody structure is associated with the introduced hybrid system in order to model its dynamics. Idea of the...
-
Surrogate modeling of impedance matching transformers by means of variable‐fidelity electromagnetic simulations and nested cokriging
PublikacjaAccurate 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...
-
Self-Organization in Multi-Agent Systems Based on Examples of Modeling Economic Relationships between Agents
PublikacjaThe goal of the research was to observe and analyze self-organization patterns in Multi-Agent Systems (MAS) by modeling basic economic relationships between agents forming a closed loop of relations necessary for their survival. The paper describes a worked-out MAS including an example of a production cycle and used economic rules. A special focus is put on behavior rules and decision systems of an individual agent such as: product...
-
Count Data Modeling About Relationship Between Dubai Housing Sales Transactions and Financial Indicators
PublikacjaIn this study, illustrating and comparing the performances of count data models such as Poisson, negative binomial (NB), Hurdle and zero-inflated models for the determination of factors affected housing sales in Dubai. Model comparisons are made via Akaike’s information criterion (AIC), the Vuong test and examining the residuals. Main purpose of this study is building reliable statistical model for relationship between Dubai housing...
-
Modeling and MANOVA studies on toxicity and endocrine potential of packaging materials exposed to different extraction schemes
PublikacjaThe stability of the linings of packaging that is in contact with the goods stored has been of major concern during decades of the development of packaging materials. In this work, an attempt was undertaken to assess the applicability of using two bioassays (Microtox® and XenoScreen YES/YAS) in estimating the stability of packaging (cans, caps, multilayer material) and the impact of their degradation on the toxicity of some simulated media....