Search
Filters
total: 5165
-
Catalog
- Publications 2455 available results
- Journals 197 available results
- Conferences 100 available results
- Publishing Houses 1 available results
- People 65 available results
- Projects 7 available results
- Laboratories 1 available results
- Research Teams 2 available results
- e-Learning Courses 134 available results
- Events 6 available results
- Open Research Data 2197 available results
displaying 1000 best results Help
Search results for: CFD COMPUTATIONS
-
Spatial Cognition and Computation
Journals -
The finite difference methods of computation of X-rays propagation through a system of many lenses
PublicationThe propagation of X-ray waves through an optical system consisting of many beryllium X-ray refrac- tive lenses is considered. In order to calculate the propagation of electromagnetic in the optical sys- tem, two differential equations are considered. First equation for an electric field of a monochromatic wave and the second equation derived for complex phase of the same electric The propagation of X-ray waves through an optical system...
-
Data Partitioning and Task Management in the Clustered Server Layer of the Volunteer-based Computation System
PublicationWhile the typical volunteer-based distributed computing system focus on the computing performance, the Comcute system was designed especially to keep alive in the emergency situations. This means that designers had to take into account not only performance, but the safety of calculations as well. Quadruple-layered architecture was proposed to separate the untrusted components from the core of the system. The main layer (W) consists...
-
Accelerated Monte Carlo method for computation of photon migration by matrix description of photon direction
PublicationPrzedstawiono metodę obliczeń dyfuzji fotonów w materiałach silnie rozpraszających, będącą modyfikacją metody Monte Carlo. Modyfikacja ta polega na zastąpieniu wektorowego opisu kierunku propagacji fotonów poprzez opis macierzowy, co pozwala na około 5% redukcję czasu obliczeń na komputerach z jednopotokowym przetwarzaniem zmiennopozycyjnym lub większą w wypadku wielopotokowego przetwarzania.
-
Implementation of high-precision computation capabilities into the open-source dynamic simulation framework YADE
PublicationThis paper deals with the implementation of arbitrary precision calculations into the open-source discrete element framework YADE published under the GPL-2+ free software license. This new capability paves the way for the simulation framework to be used in many new fields such as quantum mechanics. The implementation details and associated gains in the accuracy of the results are discussed. Besides the "standard" double (64 bits)...
-
Composites-Mechanics Computations Applications
Journals -
Computational Selectivity Assessment of Protease Inhibitors against SARS-CoV-2
Publication -
Using a computational model to compare objective negotiations in real and virtual environments
PublicationZaprezentowano obliczeniowy model negocjacji uwzględniający warunki początkowe, przebieg negocjacji i wyniki negocjacji. Przedstawiono komputerowy system wspomagający rejestrację przebiegu negocjacji i ich wyników oraz analizę negocjacji zgodną z proponowanym modelem.
-
Modeling of Performance, Reliability and Energy Efficiency in Large-Scale Computational Environment
PublicationLarge scale of complexity of distributed computational systems imposes special challanges for prediction of quality in such systems.Existing quality models for lower-scale systems include functionality,performance,reliability,flexibility and usability.Among these attributes,performance and reliability have a particular significance to the large-scale systems computing quality modeling due to their strong dependence on the system...
-
Computational issues of solving the 1D steady gradually varied flow equation
PublicationIn this paper a problem of multiple solutions of steady gradually varied flow equation in the form of the ordinary differential energy equation is discussed from the viewpoint of its numerical solution. Using the Lipschitz theorem dealing with the uniqueness of solution of an initial value problem for the ordinary differential equation it was shown that the steady gradually varied flow equation can have more than one solution....
-
The computational complexity of the backbone coloring problem for planar graphs with connected backbones
PublicationIn the paper we study the computational complexity of the backbone coloring problem for planar graphs with connected backbones. For every possible value of integer parameters λ≥2 and k≥1 we show that the following problem: Instance: A simple planar graph GG, its connected spanning subgraph (backbone) HH. Question: Is there a λ-backbone coloring c of G with backbone H such that maxc(V(G))≤k? is either NP-complete or polynomially...
-
Modeling of Performance, Reliability and Energy Efficiency in Large-Scale Computational Environments
PublicationLarge scale of complexity of distributed computational systems imposes special challenges for prediction of quality in such systems. Existing quality models for lower-scale systems include functionality, performance, reliability, flexibility and usability. Among these attributes, performance and reliability have a particular significance to the large-scale systems computing quality modeling due to their strong dependence on the...
-
The potential of computational methods for the categorization of architectural objects on the example of media architecture
PublicationThe paper presents an example of the categorization of architectural objects and assessment of the characteristics of urban space, based on the analysis of specific features of architectural objects and urban landscape. The conducted analysis refers to media architecture and is presented in the complex context of the development of media solutions. The field of influence of IT on architecture is also stressed, both on the architect’s...
-
Computational and experimental evaluation of view out according to European Standard EN17037.
PublicationThis paper presents an experimental evaluation of view out based on EN17037:2018 Daylight in Buildings within an educational building. The primary motivation to conduct the research was an introduction of a view out appraisal criteria by the mentioned standard. The study gives insights into the following: (i) the use of computational evaluation of an outside view according to the EN17037 criteria (ii) the use of the direct simultaneous...
-
Contact with coupled adhesion and friction: Computational framework, applications, and new insights
PublicationContact involving soft materials often combines dry adhesion, sliding friction, and large deformations. At the local level, these three aspects are rarely captured simultaneously, but included in the theoretical models by Mergel et al., (2019). We here develop a corresponding finite element framework that captures 3D finite-strain contact of two deformable bodies. This framework is suitable to investigate sliding friction even...
-
Experimental and computational study on mechanical behaviour of carpentry corner log joints
PublicationThis work concerns experimental and numerical research on carpentry joints used in historic wooden buildings in southeastern Poland and western Ukraine. These structures are mainly sacred buildings, and the types of corner log joints characteristic of this region are primarily saddle-notch and dovetail joints; thus, these two types of joints were analysed in this study. The modelling of historic timber structures is a complex...
-
Computational methods for calculation of binding free energy for ligand-receptor complexes
PublicationAccurate description of the molecular complexes energetic influence is required for understanding of many biological functions carried out by proteins. Therefore, estimation of binding free energy for ligand-receptor complexes is of highest importance for structure-based ligand design and drug discovery approaches.Experimental methods of determination of difference in Gibbs'es free energy have many limitations. Thus, computational...
-
A Computational Analysis of the Proton Affinity and the Hydration of TEMPO and Its Piperidine Analogs
PublicationThe study investigated the impact of protonation and hydration on the geometry of nitroxide radicals using B3LYP and M06-2X methods. Results indicated that TEMPO exhibited the highest proton affinity in comparison to TEMPOL and TEMPONE. Two pathways contribute to hydrated protonated molecules. TEMPO shows lower first enthalpies of hydration (ΔH1-M), indicating stronger H-bonding interactions, while TEMPONE shows higher values,...
-
Computational Model of Time for Stiff Hybrid Systems Applied to Control Synthesis
PublicationComputational representation.
-
Investigating an Optimal Computational Strategy to Retrofit Buildings with Implementing Viscous Dampers
PublicationCivil engineering structures may seriously suffer from different damage states re-sult of earthquakes. Nowadays, retrofitting the existing buildings is a serious need among designers. Two important factors of required performance level and cost of retrofitting play a crucial role in the retrofitting approach. In this study, a new optimal computational strategy to retrofit structures by implementing linear Viscous Dampers (VDs)...
-
Diaryl Sulfide Derivatives as Potential Iron Corrosion Inhibitors: A Computational Study
PublicationThe present work aimed to assess six diaryl sulfide derivatives as potential corrosion inhibitors. These derivatives were compared with dapsone (4,4′-diaminodiphenyl sulfone), a common leprosy antibiotic that has been shown to resist the corrosion of mild steel in acidic media with a corrosion efficiency exceeding 90%. Since all the studied compounds possess a common molecular backbone (diphenyl sulfide), dapsone was taken as the...
-
Modelling of Hydraulic Fracturing in Rocks in Non-isothermal Conditions Using Coupled DEM/CFD Approach with Two-Phase Fluid Flow Model
PublicationSkała łupkowa jest materiałem silnie niejednorodnym, nieciągłym i porowatym. W warunkach nieizotermicznych ruch płynu w układzie porów i kapilar jest silnie sprzężony z przenoszeniem ciepła. Przebieg szczeliny hydraulicznej silnie zależy od stopnia nasycenia skały. Opracowano innowacyjny model termo-hydro-mechaniczny oparty na modelu DEM w celu szczegółowego śledzenia frakcji ciecz/gaz w porach i pęknięciach pod kątem ich różnej...
-
Modelling hydraulic and capillary-driven two-phase fluid flow in unsaturated concretes at the meso-scale with a unique coupled DEM-CFD technique
PublicationThe goal of the research was to demonstrate the impact of thin porous interfacial transition zones (ITZs) between aggregates and cement matrix on fluid flow in unsaturated concrete caused by hydraulic/capillary pressure. To demonstrate this impact, a novel coupled approach to simulate the two-phase (water and moist air) flow of hydraulically and capillary-driven fluid in unsaturated concrete was developed. By merging the discrete...
-
Hydraulic fracturing process in rocks – small-scale simulations with a novel fully coupled DEM/CFD-based thermo-hydro-mechanical approach
PublicationW artykule przedstawiono dwuwymiarową (2D) symulację numeryczną szczelinowania hydraulicznego w małej skali przeprowadzoną w próbkach skał posiadających pojedynczą szczelinę wtryskową. Wykorzystano unikalny model termo-hydro-mechaniczny (THM) w skali porów oparty na DEM/CFD do symulacji dwufazowego laminarnego przepływu płynu (wody i gazu) z przenoszeniem ciepła w nienasyconych materiałach porowatych o niskiej porowatości. Korzystając...
-
The basics of design and experimental tests of the commutation unit of a hydraulic satellite motor
Publicationhe article presents an analytical method to design the commutation unit in a hydraulic satellite motor. It is shown that the size of the holes feeding the working chambers and their location on the plates closing those chambers depends on the geometrical dimensions of the working mechanism. The overlap in the commutation unit depends on the rotational speed range. It is demonstrated that the geometrical dimensions of the commutation...
-
Hydrostatically discharged commutation unit and it's impact on axial pump's performance
PublicationW pracy przedstawiono wyniki analizy teoretycznej funkcjonowania rozrządu czołowego i hydrostatycznie odciążonego rozrządu krzywkowego w pompach wielotłoczkowych osiowych. Zaprezentowano także wyniki porównawczych badań sprawności mechaniczno-ciśnieniowej, objętościowej i całkowitej dla pomp o różnej konstrukcji. Podano informacje o produkowanych obecnie pompach typu PWK.
-
System optoelektroniczny do kontroli procesów μPA CVD
PublicationPrzedstawiono prototyp optoelektronicznego systemu do monitorowania in-situ procesu CVD, wspomaganych plazmą mikrofalową. System składa się z układu optycznej spektroskopii emisyjnej OES oraz specjalizowanego spektroskopu ramanowskiego RS. Umożliwia on równoczesne monitorowanie składu plazmy oraz określanie dynamiki wzrostu i zawartości defektów warstwy. Przedstawiono wyniki badań przebiegu procesu wytwarzania warstw diamentopodobnych...
-
Surrogate models and automated cad of passive microwave components
PublicationW pracy pokazane zostały techniki modelowania złożonych układów elektronicznych wysokiej częstotliwości. Modele zastępcze mają postać sparametryzowanych modeli matematycznych tworzonych za pomocą schematów interpolacyjnych lub skupionych, pasywnych układów zastępczych dedykowanych analizie w dziedzinie czasu. Do konstrukcji modeli wykorzystywane są wyniki symulacji elektromagnetycznych, co pozwala na osiągnięcie lepszej dokładności...
-
CVD generated mesoporous hollow carbon spheres as supercapacitors
Publication -
Development of low noise CCD readout front-end
Publication -
Development of low noise CCD readout front-end
Publication -
Thin CVD diamond films - synthesis, properties, applications
PublicationThe basic model of diamond films growth, in the low pressure synthesis, deposition from the CVD gas phase, is the mixture of hydrocarbon gas in presence with activated hydrogen and its nucleation on the substrate as a result of pyrolysis reaction. It allows to cross the great energetic barrier between graphite and diamond. High pressure and temperature are replaced by change of electronic structure of atoms into gas precursors...
-
Experimental investigation of joint with positive eccentricity in CFS truss
PublicationDue to technological restrictions, in the case of trusses made of CFS open cross-sections, positive eccentricities in the truss joints have become very frequent. Therefore studies concerning the load-bearing capacity of truss joints with positive eccentricity were undertaken. It was assumed that the resistance of cold-formed steel (CFS) open cross-section truss joints located on compression chords and with positive eccentricity...
-
Projektowanie filtru DFT-VFD metodą Hooke-Jeevesa
PublicationZaletą filtrów ułamkowo opóźniających typu DFT-VFD określanych przez współczynniki ich dyskretnej charakterystyki częstotliwościowej z pasma przejściowego jest ich powiązanie z metodą okien przesuwanych. Czyni je to szczególnie przydatnymi w zastosowaniach do zmiany szybkości próbkowania. Problem stanowi jednak projektowanie tych filtrów. Dotychczas dostępna metoda POCS co prawda gwarantuje zbieżność, ale jest ona bardzo powolna....
-
Comparing of optical properties and morphology of polyoxadiazoles with CF3 groups
PublicationPurpose: The aim of this paper is to compare optical properties of 4-(1,1,1,3,3,3-hexafluoro-2(-4(-3(4-(5-(4-m-tolyoxy)phenyl)-1,3,4-oxadiazol-2-yl)phenoxy)phenylcarbomyl)phenyl)propan2-yl)-N-methylbenzamide(Oxad 6F-D) and 4-(1,1,1,3,3,3-hexafluoro-2(-4-(4-(4-(5-(4-(p-tolyoxy)phenyl)-1,3,4-oxadiazol-2-yl)phenoxycarbaomyl)phenyl)propan-2-yl)-N-methylbenzamide (Oxad 6F-E).Design/methodology/approach: The Oxad 6F polymer thin films...
-
Internet as a new platform for delivery of microwave CAD services.
PublicationZaprezentowano aplikację przeznaczoną do syntezy filtrów rezonatorowych, która jest realizacją nowego sposobu myślenia związanego z rewolucją usług internetowych, które charakteryzują się niskim kosztem tworzenia oraz szybką i bezpieczną dystrybucją. Opisano stworzoną wielowarstwową aplikację, która gwarantuje łatwy, bezpieczny oraz ograniczony dostęp do aplikacji dla szerokiego kręgu osób. Zawarto w niej algorytm szybkiej syntezy...
-
Diagnostics of cvd process by means of optical emission spectroscopy.
PublicationZastosowano optyczną spektroskopię emisyjną do badania w trybie in-situ dysocjacji cząsteczek oraz wzbudzenia i jonizacji atomów wodoru podczas procesu syntezy cienkich warstw diamentowych metodą chemicznego osadzania z par gazowych wspomaganego plazmą mikrofalową (mPACVD). Zbudowano tor światłodowy, umożliwiający sprzężenie komory CVD z systemem spektroskopowym i wykonywanie pomiarów bezinwazyjnych. Wykonano pomiary spektralne...
-
Characteristics of the Radunia river and its catchment in view of WFD
PublicationCelem Ramowej Dyrektywy Wodnej (RDW), między innymi problemami jest ochrona śródlądowych wód powierzchniowych, zabezpieczenie przed dalszym pogorszenien ich stanu i poprawa stanu ekosystemów wodnych. Badania Rzeki Raduni i jej zlewni zostały wykonane przez Instytut Budownictwa Wodnego i Politechnikę Gdańską. Dotyczyły one wód śródlądowych (rzeki, jeziora, zbiorniki), ich hydrologii, hydrauliki i jakości wody. Rzeka jest istotna...
-
TECHNIKI CAD W INŻYNIERII ELEKTRYCZNEJ - WYBRANE ZAGADNIENIA
PublicationW pracy przedstawiono różne techniki CAD (ang. Computer Aided Design) wykorzystywane w inżynierii elektrycznej dla potrzeb komputerowego modelowania 3D przetworników elektromechanicznych. Wirtualne modele 3D różnych urządzeń są użyteczne nie tylko przy opracowywaniu dokumentacji technicznej ale są także wykorzystywane w obliczeniach inżynierskich:...
-
Quadratic programming approach to coupled resonator filter cad
PublicationArtykuł prezentuje technikę komputerowego wspomagania procesu projektowania filtrów zbliżeniowych. Polega ona na sformułowaniu macierzy sprzężeń jako problemu programowania kwadratowego (QP). Dzięki zdefiniowaniu procedury optymalizacyjnej jako problemu QP, przy założeniu liniowej zależności współczynników sprzężeń od wymiarów geometrycznych struktury, uzyskano znaczącą redukcję liczby pełnofalowych symulacji prowadzących do uzyskania...
-
Development of Microstructured Carbon Coatings by Substrate-Catalytic CVD
PublicationCarbon nanostructured films were synthesized by chemical vapor deposition (CVD) on H18 stainless steel (AISI 440C) sheets with an H2/CH4/N2 gas mixture at various substrate temperatures. During the synthesis, the iron and chromium oxide layer was formed between the steel and carbonaceous layer. The carbon films exhibited wall-like and spherical morphologies and structures, as characterized by scanning electron microscopy and Raman...
-
The lipophilicity indices of flavonoids estimated by reversed-phase liquid chromatography using different computation methods
PublicationDo oceny właściwości chromatograficznych wybranych flawonoidów zastosowano wyskokosprawną chromatografię cieczową z odwróconym układem faz i kolumnami chromatograficznymi typu C-8 i C-18.Lipofilowość wyrażono za pomocą różnych deskryptów lipofilowości.
-
Greedy Multipoint Model-Order Reduction Technique for Fast Computation of Scattering Parameters of Electromagnetic Systems
PublicationThis paper attempts to develop a new automated multipoint model-order reduction (MOR) technique, based on matching moments of the system input–output function, which would be suited for fast and accurate computation of scattering parameters for electromagnetic (EM) systems over a wide frequency band. To this end, two questions are addressed. Firstly, the cost of the wideband reduced model generation is optimized by automating a...
-
Full scale CFD seakeeping simulations for case study ship redesigned from V-shaped bulbous bow to X-bow hull form
PublicationIncreasing propulsion efficiency, safety, comfort and operability are of the great importance, especially for small ships operating on windy sites like the North Sea and the Baltic Sea. Seakeeping performance of ships and offshore structures can be analysed by different methods and the one that is becoming increasingly important is CFD RANS. The recent development of simulation techniques together with rising HPC accessibility...
-
COMPUTATIONAL MECHANICS
Journals -
Role of Glycosaminoglycans in Procathepsin B Maturation: Molecular Mechanism Elucidated by a Computational Study
Publication -
The computational complexity of the backbone coloring problem for bounded-degree graphs with connected backbones
PublicationGiven a graph G, a spanning subgraph H of G and an integer λ>=2, a λ-backbone coloring of G with backbone H is a vertex coloring of G using colors 1, 2, ..., in which the color difference between vertices adjacent in H is greater than or equal to lambda. The backbone coloring problem is to find such a coloring with maximum color that does not exceed a given limit k. In this paper, we study the backbone coloring problem for bounded-degree...
-
Synthesis, spectroscopy and computational studies of some biologically important hydroxyhaloquinolines and their novel derivatives
PublicationA series crystalline compounds of methyl and phosphinyl derivatives of 2-methylquinolin-8-ol (1a) and related 5,7-dichloro-2-methylquinolin-8-ol (1b) were quantitatively prepared and characterized by microanalysis, IR, UV-vis and multinuclear NMR spectroscopy. Five of them have been characterized by single crystal X-ray diffraction method. The known compounds, 8-methoxy-2-methylquinoline (2a) and 8-methoxyquinoline (2d), were synthesised...
-
A proposition of the computational model for the dynamic analysis of stress and strain distribution in the hip joint
PublicationCelem pracy jest sformułowanie zadania modelowania dynamiki odkształceń i rozkładu naprężeń stawu biodrowego, a w szczególności kości udowej, pod wpływem sił mięśniowych oraz zadanych sił zewnętrznych. Rozwiązanie tego zadania pozwoli wyjaśnić niektóre zjawiska np. jakie ruchy kości udowej oraz jakie materiały użyte do jej alloplastyki są przyczyną urazów i poważnych uszkodzeń. Omówiono problemy związane z zastosowaniem metody...
-
Validation Process for Computational Model of Full-Scale Segment for Design of Composite Footbridge
PublicationExperimental tests and numerical simulations of a full-scale segment of a foot and cycle bridge made of polymer composites are presented in the paper. The analysed structure is made of sandwich panels, which consist of glass fibre reinforced polymer (GFRP) multi-layered laminate faces and a PET foam (obtained from recycling) core. The dimensions of the segment cross-section are the same as for the target footbridge; however, span...