Filtry
wszystkich: 3638
wybranych: 3146
-
Katalog
- Publikacje 3146 wyników po odfiltrowaniu
- Czasopisma 76 wyników po odfiltrowaniu
- Konferencje 12 wyników po odfiltrowaniu
- Osoby 47 wyników po odfiltrowaniu
- Wynalazki 1 wyników po odfiltrowaniu
- Projekty 4 wyników po odfiltrowaniu
- Kursy Online 78 wyników po odfiltrowaniu
- Wydarzenia 8 wyników po odfiltrowaniu
- Dane Badawcze 266 wyników po odfiltrowaniu
Filtry wybranego katalogu
wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: FLUID FILM MODELS
-
Time fractional analysis of Casson fluid with application of novel hybrid fractional derivative operator
PublikacjaA new approach is used to investigate the analytical solutions of the mathematical fractional Casson fluid model that is described by the Constant Proportional Caputo fractional operator having non-local and singular kernel near an infinitely vertical plate. The phenomenon has been expressed in terms of partial differential equations, and the governing equations were then transformed in non-dimensional form. For the sake of generalized...
-
Influence of electropolymerization conditions on the morphological and electrical properties of PEDOT film
PublikacjaIn this work the effects of electropolymerization conditions on the morphological properties and conductivity of poly(3,4-ethylenedioxythiophene) (PEDOT) film have been studied. PEDOT films were electrochemically synthesized in a one step process from acetonitrile solution containing 3,4-ethylenedioxythiophene (EDOT) and lithium perchlorate. Based on atomic force microscopy, scanning electron microscopy, cyclic voltammetry and...
-
Thick film traps with an irregular film. Preparation and evaluation.
PublikacjaOpisano nową metodę wytwarzania otwartych pułapek kapilarnych do wzbogacania lotnych związków organicznych z próbek gazowych. Badanie właściwości tego typu pułapek wykazało, że spadek ich sprawności chromatograficznej w porównaniu z pułapkami z filmem regularnym, jest rzędu 20-30%. Opracowana technologia jest bardzo prosta i pozwala na szybkie i tanie wytwarzanie dużych ilości pułapek z grubymi filmami również przez niewyspecjalizowane...
-
Wettability of shale rock as an indicator of fracturing fluid composition
PublikacjaShales have become one of the main unconventional gas resources in the world. However, physicochemical properties of rocks are still at the center of research. There have been conducted major researches in wettability of shales by fluids and advances in understanding and control of shale rock wettability. Also influence of interfacial phenomena on a production capacity of reservoirs have been made. The aim of this study is to find...
-
Laser patterned platform with PEDOT–graphene composite film for NO2 sensing
PublikacjaThis work presents a simple and fully electrochemical route used for fabricating of a NO2 gas sensor made of reduced-graphene-oxide-poly(3,4-ethylenedioxythiophene) composite film. The sensing platform was fabricated from alumina substrate and equipped with gold interdigitated electrodes and built-in heater.The temperature distribution on the surface of interdigitated electrodes was investigated by a thermalimaging camera and compared...
-
OBTAINING FLUID FLOW PATTERN FOR TURBINE STAGE WITH NEURAL MODEL.
PublikacjaIn the paper possibility of applying neural model to obtaining patterns of proper operation for fluid flow in turbine stage for fluid-flow diagnostics is discussed. Main differences between Computational Fluid Dynamics (CFD) solvers and neural model is given, also limitations and advantages of both are considered. Time of calculations of both methods was given, also possibilities of shortening that time with preserving the accuracy...
-
A Concept of Automatic Film Color Grading Based on Music Recognition and Evoked Emotions
PublikacjaThe article presents the aspects of the final selection of the color of shots in film production based on the psychology of color. First of all, the elements of color processing, contrast, saturation or white balance in the film shots were presented and the definition of color grading was given. In the second part of the article the analysis of film music was conducted in the context of stimulating appropriate emotions while watching...
-
Acoustic Heating Produced in the Thermoviscous Flow of a Shear-Thinning Fluid
PublikacjaThis study is devoted to the instantaneous acoustic heating of a shear-thinningfluid. Apparent viscosity of a shear-thinning fluid depends on the shear rate. Thatfeature distinguishes it from a viscous Newtonian fluid. The special linear combi-nation of conservation equations in the differential form makes it possible to derivedynamic equations governing both the sound and non-wave entropy mode inducedin the field of sound. These...
-
New Generation of Water lubricated Foil bearing - Numerical Models and Experimental Verification
PublikacjaIn the paper a new idea of foil water lubricated bearing and methodology of hydrodynamic characteristics calculations is presented. To assesses the theoretical characteristics of these bearings two different computer models were built. First is structural model coupled with fluid model. It takes into account: fluid flow in the deformed fluid gap, specific design of bearing support and friction in bearing support. The second is...
-
Performance Evaluation of Asphalt Binder Modified with Shear Thickening Fluid
PublikacjaThis paper aims at using a dilatant or shear thickening fluid (STF) [a non-Newtonian fluid consisting of particles of nano-silica suspended in a liquid medium, i.e., ethylene glycol (EG), which acts as a carrier fluid; proportion 40:60] as additive or modifier of bitumen in order to enhance its viscoelastic properties. A commonly-used performance grading (PG) system, storage stability test, and different conventional and rheological...
-
Simulation of fluid structure interaction in a novel design of high pressure axial piston pump
PublikacjaA novel type of an axial, piston-driven high pressure hydraulic pump with variable capacity marks a significant improvement in the area of the hydraulic machinery design. Total discharge from hydrostatic forces eliminates a need for a servomechanism, thus simplifying operation, reducing weight and introducing the possibility of the pump displacement control by computer. PWK-type pumps, invented in the Gdansk University of Technology,...
-
Three dimensional fluid equations from distribution function with discontinuity in velocity space
PublikacjaUkład równań typu hydrodynamicznego dla rozwarstwionego gazu w polu grawitacyjnym jest wyprowadzony z równania BKG przy użyciu metody kawałków ciągłej funkcji dystrybucji. Otrzymany układ równań uogólnia układ Naviera-Stokesa dla dowolnych liczb Knudsena.
-
Improved model of isothermal and incompressible fluid flow in pipelines versus the Darcy–Weisbach equation and the issue of friction factor
PublikacjaIn this article, we consider the modelling of stationary incompressible and isothermal one-dimensional fluid flow through a long pipeline. The approximation of the average pressure in the developed model by the arithmetic mean of inlet and outlet pressures leads to the known empirical Darcy–Weisbach equation. Most importantly, we also present another improved approach that is more accurate because the average pressure is estimated...
-
Microcrystalline diamond film evaluation by spectroscopic optical coherence tomography
PublikacjaThis study has focused on the microcrystalline diamond film (MCD) thickness evaluation. For this purpose, optical coherence tomography (OCT) enhanced by spectroscopic analysis has been used as a method of choice. The average thickness of the tested layer was about 1.5 µm, which is below the standard 2-point OCT resolution. In this case, the usefulness of the spectroscopic analysis was confirmed for the evaluation of the thickness...
-
Efficiency of acoustic heating produced in the thermoviscous flow of a fluid with relaxation
PublikacjaInstantaneous acoustic heating of a fluid with thermodynamic relaxation is the subject of investigation. Among others, viscoelastic biological media described by the Maxwell model of the viscous stress tensor, belong to this type of fluid. The governing equation of acoustic heating is derived by means of the special linear combination of conservation equations in differential form, allowing the reduction of all acoustic terms in...
-
In-situ and ex-situ resistance measurements of polypyrrole film using double-band electrode
PublikacjaMany in-situ techniques are performed in order to determine the resistance of conducting polymer film. However, the resistance measured in solution can be the combination of polymer resistance and that of other components, such as resistance of supporting electrolyte. Therefore, in this work, the influence of the solution on the resistance of polypyrrole (PPy) film has been studied. PPy film was electrchemically synthesized onto...
-
A universal NDT method for examination of low energy impact damage in CFRP with the use of TLC film
PublikacjaThe article presents an attempt to use a sheet of laminated thermochromic liquid crystal film (TLC film) for non-destructive testing of the impact damage (energy values: 1J, 2J, 3J and 4J) in carbon fibre-reinforced polymer (CFRP). This is a new, alternative NDT approach based on the thermo-optical effect. The main advantages of this method are a) the low cost of TLC film, b) the low cost of recording devices due to the usage of...
-
FAILURE OF MAGNETIC FLUID SEALS OPERATING IN WATER: PRELIMINARY CONCLUSIONS
PublikacjaThe article analyses properties of magnetic fluid seals installed in rotary sealing no des which operate in the utility water environment. Seals of this type have been examined as a possible solution to the problem with ship manoeuvring propulsion sealing. The present analysis bases on laboratory durability tests of magnetic fluid seals expo sed to long - term utility water loads, at different water pressures and shaft revolutions....
-
Enhanced energy conversion as a result of fluid-solid interaction in micro- and nanoscale
PublikacjaIt is known that nano- and micromechanics require new approaches to right describing of surface-like phenomena which lead to an enhanced energy conversion. In this work, a general form of surface forces that consist of a contribution from both the friction and mobility components has been extended to collect the effects of bulk and surface motion of a fluid. Quite similar impact can be observed for a solid-fluid mixture, where...
-
Simulation of fluid structure interaction in a novel design of high pressure axial piston hydraulic pump
PublikacjaA novel type of an axial, piston-driven high pressure hydraulic pump with variable capacity marks a significant improvement in the area of the hydraulic machinery design. Total discharge from hydrostatic forces eliminates a need for a servomechanism, thus simplifying operation, reducing weight and introducing the possibility of the pump displacement control by computer. PWK-type pumps, invented in the Gdansk University of Technology,...
-
Application of bismuth film electrode for determination of heavy metals by stripping voltammetry
PublikacjaWhen Wang's research group introduced a new type of a working electrode: bismuth film plated electrode (BiFE), it has started attracting increasing attention in the field of electrochemical stripping analysis. These electrodes are shown to be very attractive alternative to common mercury-based electrodes, which are predominantly used in analysis of trace heavy metals.For the determination of heavy metals (Zn, Cd, Pb, Cu) used square...
-
Vortex flow caused by periodic and aperiodic sound in a relaxing maxwell fluid
PublikacjaThis paper concerns the description of vortex flow generated by periodic and aperiodic sound in relaxing Maxwell fluid. The analysis is based on governing equation of vorticity mode, which is a result of decomposition of the hydrodynamic equations for fluid flow with relaxation and thermal conductivity into acoustical and non-acoustical parts. The equation governing vorticity mode uses only instantaneous, not averaged over sound...
-
Application of the fluid–structure interaction technique for the analysis of hydrodynamic lubrication problems.
PublikacjaFluid–structure interaction technique seems to be one of the most promising possibilities for theoretical analysis of lubrication problems. It allows coupling of different physical fields in one computational task, taking into account the interaction between them. In this article, two sets of fluid–structure interaction analyses focusing on the bearing performance evaluation are presented. One analysis was applied to a water-lubricated...
-
Pharmaceutical and forensic drug applications of chiral supercritical fluid chromatography
PublikacjaTHE SUPERCRITICAL FLUID IS AN EXCELLENT CHOICE AS THE CHROMATOGRAPHIC MOBILE PHASE BECAUSE IT ALLOWS RAPID SEPARATION WITH HIGH EFFICIENCY AND APPLICATIONS INVOLVING ENANTIORESOLUTION ARE COMMON. SUPERCRITICAL FLUID CHROMATOGRAPHY (SFC) IS INCREASINGLY USED FOR ANALYTICAL, SEMI-PREPARATIVE AND PREPARATIVE PURIFICATION OF CHIRAL COMPOUNDS, INCLUDING PRODUCTION OF ENANTIOMERS THAT ARE MAINLY ENCOUNTERED DURING DRUG DEVELOPMENT. SFC...
-
Optical properties of thin TiO2 film deposited on the fiber optic sensor head
PublikacjaThe presented study was focused on investigation of the titanium dioxide (TiO2) thin film deposited on the fiber tip. The intention of this investigation was using TiO2 film in the construction of the optical fiber sensor head. In the demonstrated construction TiO2 thin layer was deposited on the tip of a commonly used telecommunication single mode optical fiber (SMF-28) by means of the Atomic Layer Deposition (ALD). Thickness...
-
Application of spatial neural simulators of turbine blade rows to fluid flow diagnostics
PublikacjaThis chapter presents the results of neural modelling of fluid flow in steam turbine row. In modelling working conditions of the flow channel varied, thus the aim of the work was to reconstruct the reference state - distributions of velocity, pressure, and losses in flow channel - with high accuracy for fluid flow diagnostics.
-
NEW DESIGNS OF CENTRIFUGAL MAGNETIC FLUID SEALS FOR ROTATING SHAFTS IN MARINE TECHNOLOGY
PublikacjaThe centrifugal magnetic fluid seals have important advantage over the conventional centrifugal seals. They maintain very good sealing capacity at static, medium and high speeds of shaft rotation, with the increased seal lifetime, and minimum torque and static friction. These seals are particularly useful in cases when the angular shaft velocity varies and sometimes decreases to nearly or exactly zero, such as in flywheel applications,...
-
Design Equation for Stirring Fluid by a Stream Pump in a Circulating Tank
PublikacjaA circulating tank is a very useful theoretical scheme for many fluid-flow objects in several branches of engineering. The motion of the fluid in such objects can be induced in different ways. A stream pump provides an especially interesting possibility; however, the quantitative description of such devices shows some shortcomings. Such a device is analogous to a jet pump, thus has similar advantages (simplicity of construction,...
-
The oil film parameters of the wankel engine apex seal in aspects of durability of mating elements
PublikacjaThe Wankel engine is one of only few alternatives to the reciprocating engines. The advantages such as good value of maximum engine power to its mass ratio are still present and can have great sense in selected fields of application, for example General Aviation. Nevertheless the disadvantages of the Wankel engine design have never lost its importance and still pose an obstacle to wider use of the Wankel engine. One of the main...
-
Development of beltless respiration and heartbeat sensor based on flexible piezoelectric film
PublikacjaThe main goal of this work is to report initial development on a respiration and heartbeat measurement sensor that can be used in continuous monitoring conditions at a minimal impact on the patient. General description of the sensor, consisting of a PVDF film and the bonding layer, is given. Open-circuit voltage generated by the sensor is estimated by analytical and numerical calculations. Analog and digital interface used to extract...
-
Life tests of a rotary single-stage magnetic-fluid seal for shipbuilding applications
PublikacjaUse of the magnetic fluid seal technology in water is much more difficult technological problem in comparisonto gas or vacuum environment. Some seals constructed up to time been are designed as hybrid, two stagesealing structures with shields or mechanical seals used as protection measures to the magnetic fluid seal.Anyway, there is always problem with immediate contact between magnetic fluid and the environmentalliquid. In the...
-
Direct amination of boron-doped diamond by plasma polymerized allylamine film
PublikacjaA novel microwave pulsed-plasma based method for the modification of the hydrogen-terminated polycrystalline boron-doped diamond (BDD) with a thin film of polymerized allylamine (PPAAm) is reported. A modified BDD surface is resistant to hydrolysis and delamination and is characterized by a high density of positively charged amino groups. Pulsed microwave plasma was applied to improve the degree of cross-linking and bonding of...
-
Tuning of the plasmon resonance location in Au nanostructures coated with a ultrathin film of Al2O3 – Optical measurements and FDTD simulations
PublikacjaThe Au nanostructures have been coated with an ultra-thin films of amorphous aluminium oxide. Optical absorption spectra show the influence of the thickness of Al2O3 on plasmon resonance wavelength. The observed red-shift of the resonance location with the increase of the thickness of the Al2O3 film, can be explained by the change in the dielectric function of this film. It allows control of the optical spectra of the coated particles....
-
Running performance of an aerodynamic journal bearing with squeeze film effect
PublikacjaResults of theoretical and experimental studies concerning the performance of an aerodynamic journal bearing of which running is assisted by squeeze film ultrasonic levitation (SFUL) are presented in this paper. The SFUL mechanism not only can separate journal from the bearing at the start and stop phases of operation but also can significantly contribute to the dynamic stability of the bearing when it runs at speed. Computer calculations...
-
Trawl-Door Shape Optimization with 3D CFD Models and Local Surrogates
PublikacjaDesign and optimization of trawl-doors are key factors in minimizing the fuel consumption of fishing vessels. This paper discusses optimization of the trawl-door shapes using high-fidelity 3D computational fluid dynamic (CFD) models. The accurate 3D CFD models are computationally expensive and, therefore, the direct use of traditional optimization algorithms, which often require a large number of evaluations, may be prohibitive....
-
DEVELOPMENT OF THE ALGORITHM OF POLISH LANGUAGE FILM REVIEWS PREPROCESSING
PublikacjaThe algorithm and the software for conducting the procedure of Preprocessing of the reviews of films in the Polish language were developed. This algorithm contains the following steps: Text Adaptation Procedure; Procedure of Tokenization; Procedure of Transforming Words into the Byte Format; Part-of-Speech Tagging; Stemming / Lemmatization Procedure; Presentation of Documents in the Vector Form (Vector Space Model) Procedure; Forming...
-
Language Models in Speech Recognition
PublikacjaThis chapter describes language models used in speech recognition, It starts by indicating the role and the place of language models in speech recognition. Mesures used to compare language models follow. An overview of n-gram, syntactic, semantic, and neural models is given. It is accompanied by a list of popular software.
-
Influence of Fluid Compressibility and Movements of the Swash Plate Axis of Rotation on the Volumetric Efficiency of Axial Piston Pumps
PublikacjaThis paper describes the design of a swash plate axial piston pump and the theoretical models describing the bulk modulus of aerated and non-aerated fluids. The dead space volume is defined and the influence of this volume and the fluid compressibility on the volumetric efficiency of the pump is considered. A displacement of the swash plate rotation axis is proposed to reduce the dead space volume for small swash plate swing angles....
-
Minimum drag shape bodies moving in inviscid fluid - revisited
PublikacjaThis paper presents the classic approach to minimum drag shape body problem, moving at hypersonic speeds, leading to famous power law shapes with value of the exponent of 3/4. Two- and three-dimensional cases are considered. Furthermore, an exact pseudo solution is given and its uselessness is discussed. Two new solutions are introduced, namely an approximate solution due to form of the functional and solution by means of optimisation...
-
Models of Structures in Didactics
PublikacjaThe final aim of teaching students subjects, such as structural mechanics, reinforced concrete, and steel structures is to teach them how structures work in a given building as well as to provide them with skills enabling them to calculate and design structures. The behavioral model of the structure, contrary to the architectural model, which focuses mainly on the external form of the building, shows workings from both the static...
-
Bridging the gap between business process models and use-case models
PublikacjaToday's software development methodologies are equipped with a plethora of methods and techniques for business process engineering and Requirements Engineering. However, heavy investments in IT have not brought forth expected results. What seems to be lacking is a systematic approach that consolidates both disciplines to gain a synergistic effect. To address this challenge we extend Use-Case Driven Approach (UCDA) by binding use...
-
Double layer adhesive silicone dressing as a potential dermal drug delivery film in scar treatment
PublikacjaThe present studies focused on the evaluation of design of an adhesive silicone film intended for scar treatment. Developed silicone double layer film was examined in terms of its future relevance to therapy and applicability on the human skin considering properties which included in vitro permeability of water vapor and oxygen. In order to adapt the patches for medical use in the future there were tested such properties as...
-
Comparison of technology adoption models
PublikacjaThere are several technology adoption models, that try to explain, how and why the technologies are adopted and used. Among those, that are widely used to explain, how the older adults accept technologies, there are some general models and models specific to the group of older users. Among the general ones I would recommend paying attention to the following models: Technology Acceptance Model (TAM) proposed by Davis...
-
Kriging Models for Microwave Filters
PublikacjaSurrogate modeling of microwave filters’ response is discussed. In particular, kriging is used to model either the scattering parameters of the filter or the rational representation of the filter’s characteristics. Surrogate models for these two variants of kriging are validated in solving a microwave filter optimization problem. A clear advantage of surrogate models based on the rational representation over the models based on scattering...
-
Thermal self-action effects for acoustic beams containing fronts in a Maxwell relaxing fluid
PublikacjaThis paper examines the thermal self-action of acoustic beams in a Maxwell relaxing fluid. This type of thermal self-action differs from that in a Newtonian fluid and behaves differently depending on a ratio of sound period and time of thermodynamic relaxation. The self-action which relates to sound beams containing shock fronts is also discussed. In addition, stationary and non-stationary types of self-action are considered.
-
Numerical simulations of transonic flow with film cooling and jet vortex generators
PublikacjaW pracy przedstawiono wyniki obliczeń przepływu transonicznego na stronie ssącej łopatki turbiny gazowej. Obliczenia wykonano dla geometrii komory pomiarowej w tunelu transonicznym IMP PAN, zaprojektowanej tak, aby odwzorować warunki przepływowe istniejące w palisadzie turbinowej. Przedstawiono wyniki obliczeń przepływu z zastosowaniem otworów chłodzących (film cooling) oraz strumieniowych generatorów wirów. Porównano je z danymi...
-
Multibody models for gait analysis
PublikacjaThe aim of this study was to create multibody biomechanical models to analyze a normal gait of the human. Proposed models can be used to identify joint moments of the lower limbs during normal gait in the single and double support phases. Applying Newton-Euler formulation, following planar models were developed: 1) a mathematical 6DOF model describing a gait in the sagittal plane of the body for single support phase and double...
-
Study of the NO2 sensing mechanism of PEDOT-RGO film using in situ Raman Spectroscopy
PublikacjaIn this work, the mechanism of the NO2 reaction with PEDOT-RGO composite film has been investigated via in situ Raman spectroscopy. Reduced graphene oxide (RGO), poly(3,4-ethylenedioxytiophene)-reduced graphene oxide (PEDOT-RGO) and poly(3,4-ethylenedioxytiophene)/ClO4− (PEDOT/ClO4−) films were fabricated using an electrodeposition method and used as resistance sensors of gaseous nitrogen dioxide. The experimental results indicate...
-
EXPERIMENTAL STUDY OF SURFACE ROUGHNESS EFFECT ONTHE RHEOLOGICAL BEHAVIOR OF MR FLUID
PublikacjaPaper presents the results of shear stress measurements of a commercial magnetorheological fluid using a plate-plate type geometry with a modified working surface. The purpose of the study was to determine the effect of changing the roughness of the measuring plate on the obtained shear stress results. Controlled shear rate tests and Magneto Sweep measurements were carried out for three MR fluid layer heights. The tests were...
-
Role of nitrogen in optical and electrical band gaps of hydrogenated/hydrogen free carbon nitride film
PublikacjaWe report the optical and electrical band gap energy of amorphous hydrogenated carbon nitride (a-HCNx) and carbon nitride (a-CNx) as a function of nitrogen concentration (N/C). The optical band gap of a-HCNx and a-CNx films has been determined by means of Ellipsometry and UV-VIS. Both optical and electrical band gaps increase with elevated nitrogen concentration. Experimentally obtained electrical band gap is compared with the...