Filtry
wszystkich: 225
wybranych: 221
Wyniki wyszukiwania dla: TERNANRY HYBRID NANOPARTICLES HYPERBOLIC TANGENT MODEL
-
Resonance Frequency Calculation of Spherical Microstrip Structure Using Hybrid Technique
PublikacjaIn this paper the spherical microstrip structure is considered. The structure is composed of a metallic patch with an arbitrary shape placed on a dielectric coated metallic sphere. In the analysis the hybrid technique is utilized. In this approach the finite-difference technique is applied in a cavity model to determine the current basis functions on the patch. Next, using method of moments, the resonance frequency of the structure...
-
The effect of microemulsion composition on the morphology of Pd nanoparticles deposited at the surface of TiO2 and photoactivity of Pd-TiO2
PublikacjaA series of microemulsion (ME) system, constituted by different water to surfactant molar ratios (Wo) and oil to surfactant mass ratios (S), have been applied for Pd-TiO2 preparation. The effect of ME properties on the morphology of Pd nanoparticles formed at TiO2 surface and an effect of Pd size and distribution on the surface and photocatalytic properties of Pd-TiO2 were investigated. Microemulsion systems were characterized...
-
Heat Transfer of the Multicolor-Laser-Sources-Irradiated Nanoparticles in Reference to Thermal Processes
PublikacjaUnlike the standard materials, metallic nanoparticles offer enhancing the heat convertion rate which implies the maximum and average temperature boost significantly in the considered system. The work’s purpose is to examine heat transfer in the metallic nanoparticles which have been deposited on a glassy substrate, enabling the nanostructures thermoablation. Furthermore, the functionalized substrate is irradiated with multicolor-laser-sources,...
-
Periodic and chaotic dynamics in a map‐based neuron model
PublikacjaMap-based neuron models are an important tool in modeling neural dynamics and sometimes can be considered as an alternative to usually computationally costlier models based on continuous or hybrid dynamical systems. However, due to their discrete nature, rigorous mathematical analysis might be challenging. We study a discrete model of neuronal dynamics introduced by Chialvo in 1995. In particular, we show that its reduced one-dimensional...
-
Four Degree-of-Freedom Hydrodynamic Maneuvering Model of a Small Azipod-Actuated Ship With Application to Onboard Decision Support Systems
PublikacjaThe main contribution of this paper is a numerical ship motion model of NTNU’s research vessel Gunnerus, capturing the surge, sway, roll, and yaw dynamics when sailing in uniform and steady currents. The model utilizes a crossflow drag formulation for the transverse viscous loads, and it includes a nonlinear formulation for the propulsion and steering loads provided by two azipod thrusters. A wide range of experimental data obtained...
-
Koncepcja i symulacja polowa generatora o zmiennej częstotliwości. Zastosowanie w autonomicznych systemach elektroenergetycznych = Conception and field simulations of a variable frequency generator. Application for autonomous power generation system
PublikacjaStreszczenie angielskie: This paper covers a conception and simulation results for a brushless synchronous generator working with variable speed in an autonomous energy generation system (e.g. airplane power grid, hybrid vehicle, micro-CHP). The papers has two parts: presentation of the generator conception used in modern autonomous energy generation systems, and simulation results using filed model elaborated in Flux2D software....
-
Modeling the impact of rotor movement on non-linearity of motor currents waveforms in high-speed PMSM drives
PublikacjaMotor current measurement techniques as well as predictive control algorithms for electric drives rely on an assumption of linear motor currents changes resulting from constant inverter output voltages. Recent research has reported that this assumption does not hold in motors with short electrical time constant, and in drives whose rotor position advances substantially during a control period. This paper proposes a simulation model...
-
Mitigating metal-organic framework (MOF) toxicity for biomedical applications
PublikacjaMetal-organic frameworks (MOFs) are a novel class of crystalline porous materials, consisting of metal ions and organic linkers. These hybrid materials are highly porous and have a large specific surface area, making them of great interest for applications in gas separation, energy storage, biomedical imaging, and drug delivery. As MOFs are being explored for biomedical applications, it is essential to comprehensively assess their...
-
Koncepcja i modelowanie silnika o wirującym tworniku oraz magneśnicy do zastosowania w napędzie miejskiego samochodu elektrycznego
PublikacjaW artykule zaprezentowano koncepcję, model oraz prototyp silnika z wirującym twornikiem oraz magneśnicą. Opisano historię powstania i zastosowania tego typu silników w motoryzacji. Przedstawiono nowoczesne rozwiązania konstrukcyjne i zastosowania we współczesnych samochodach elektrycznych i hybrydowych. Opracowano model silnika z wirującym twornikiem i magneśnicą oraz przedstawiono wybrane wyniki symulacji przeprowadzone w programie...
-
Znaczenie i dynamika efektuacji w działaniach zespołów projektowych IT
PublikacjaCel: Celem opracowania jest sprawdzenie, na ile wdrażanie zasad efektuacji jest korzystne dla efektywności zespołów projektowych pracujących nad innowacyjnymi rozwiązaniami i czy wpływa na ich satysfakcję. Metodyka badań: Badania ilościowe zrealizowano w studenckich zespołach projektowych z branży IT, opracowujących rozwiązania na zlecenie interesariuszy zewnętrznych. Do pomiaru zmiennych wykorzystano autorskie kwestionariusze....
-
Some Aspects of Shear Behavior of Soft Soil–Concrete Interfaces and Its Consequences in Pile Shaft Friction Modeling
PublikacjaThis paper examines the stiffness degradation and interface failure load on soft soil–concrete interface. The friction behavior and its variability is investigated. The direct shear tests under constant normal load were used to establish parameters to hyperbolic interface model which provided a good approximation of the data from instrumented piles. Four instrumented piles were used to obtain reference soil–concrete interface behavior....
-
Titanium lanthanum three oxides decorated magnetic graphene oxide for adsorption of lead ions from aqueous media
PublikacjaThe current study presents a viable and straightforward method for synthesizing titanium lanthanum three oxide nanoparticles (TiLa) and their decoration onto the ferrous graphene oxide sheets to produce FeGO-TiLa as efficient magnetic adsorbent. Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and vibration sample magnetometer (VSM) were used to evaluate...
-
BACTERIAL INACTIVATION VIA LASER-DRIVEN GOLD NANOPARTICLE HEATING: SIMULATION AND ANALYSIS
PublikacjaThis study utilizes CFD technique to simulate the inactivation of E. coli bacteria within a microfluidic chamber, employing gold nanoparticles irradiated by a laser beam. Employing a single-phase model, the presence of bacteria is considered by treating thermal properties in the governing equations as effective, combining those of water and bacteria using established correlations from scientific literature. The conversion of light...
-
Natural convective heat transfer from isothermalconic
PublikacjaTheoretical considerations on convective heat transfer from isothermal upward conicalsurfaces have been presented. The physical model of this phenomenon consists of an isothermalcone of inclination angle (φ) between the cone generating line (X) and the radius (R) of the cone base. The angle is a parameter of conical surface which varied from (φ = 0−circular horizontal plate) to (φ = π/2—vertical cylinder) . Onthe basis of Navier–Stokes...
-
Optimal spindle speed determination for vibration reduction during ball-end milling of flexible details
PublikacjaIn the paper a method of optimal spindle speed determination for vibration reduction during ball-end milling of flexible details is proposed. In order to reduce vibration level, an original procedure of the spindle speed optimisation, based on the Liao–Young criterion, is suggested. As the result, an optimal, constant spindle speed value is determined. For this purpose, on-stationary computational model of machining process is...
-
Modeling the effect of electric vehicles on noise levels in the vicinity of rural road sections
PublikacjaNumerous European countries experience a steady increase in the share of electric (EV) and hybrid electric (HEV) vehicles in the traffic stream. These vehicles, often referred to as low- or zero-emission vehicles, significantly reduce air pollution in the road environment. They also have a positive effect on noise levels in city centers and in the surroundings of low-speed roads. Nevertheless, issues related to modeling noise from...
-
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...
-
Deep learning for recommending subscription-limited documents
PublikacjaDocuments recommendation for a commercial, subscription-based online platform is important due to the difficulty in navigation through a large volume and diversity of content available to clients. However, this is also a challenging task due to the number of new documents added every day and decreasing relevance of older contents. To solve this problem, we propose deep neural network architecture that combines autoencoder with...
-
Turbulence model evaluation for numerical modelling of turbulent flow and heat transfer of nanofluids
PublikacjaIn this work, Nusselt number and friction factor are calculated numerically for turbulent pipe flow (Reynolds number between 6000 and 12000) with constant heat flux boundary condition using nanofluids. The nanofluid is modelled with the single-phase approach and the simulation results are compared with experimental data. Ethylene glycol and water, 60:40 EG/W mass ratio, as base fluid and SiO2 nanoparticles are used as nanofluid...
-
Magnetic semiconductor photocatalysts for the degradation of recalcitrant chemicals from flow back water
PublikacjaIn the present study treatability of persistent organic compounds from the flow back water after hydrauling fracturing was investigated. The combination of TiO2 photocatalyst and magnetic oxide nanoparticles enhance the separation and recoverable property of nanosized TiO2 photocatalyst. Fe3O4/ TiO2 and Fe3O4@SiO2/TiO2 nanocomposites were prepared by heteroagglomeration. The photocatalysts’ characteristics by X-ray diffractometry...
-
Towards an integrated assessment of environmental and human health impact of energy sector in Poland
PublikacjaReferat prezentuje system zintegrowanej oceny wpływu sektora energetycznego na stan środowiska i zdrowie ludzkie w Polsce. W podejściu wykorzystano kombinację modelu transportu zanieczyszczeń w powietrzu POLAIR 3D z modelem informacyjno-symulacyjnym RAINS. Model oszacowuje emisje i koncentracje zanieczyszczeń powietrza, koszty kontroli emisji zanieczyszczeń i inne koszty związane z różnymi scenariuszami rozwoju sektora energetycznego.The...
-
Hybrid stepless distribution transformer with four-quadrant AC/DC/AC converter at low voltage side - simulation tests
PublikacjaThe article presents the work of the stepless hybrid distribution transformer (HT), as an alternative to the so far applied Automatic Voltage Regulator (AVR) solutions, used to control the voltage in the power system in terms of the fundamental harmonic. The HT is a combination of a conventional distribution transformer and an AC/DC/AC converter connected in series with the transformers secondary winding. In the work the basic...
-
Detection of debonding in reinforced concrete beams using ultrasonic transmission tomography and hybrid ray tracing technique
PublikacjaThis paper concerns inspection of reinforced concrete elements, with particular emphasis on assessing the quality of the adhesive connection between steel and concrete. A novel theoretical model was developed to determine the paths of transmitted, refracted and reflected elastic waves as well as a creeping wave propagated along the inclusion surface. Imaging the internal structure of tested beams was based on wave propagation measurements...
-
Microwave Characterization of Dielectric Sheets in a Plano-Concave Fabry-Perot Open Resonator
PublikacjaDespite its long history, a double-concave (DC) Fabry-Perot open resonator (FPOR) has recently gained popularity in the characterization of dielectrics in the 20–110 GHz range, mainly due to such novel accomplishments as full automation of the measurement process and the development of even ore accurate and computationally efficient electromagnetic model. However, it has been discovered that such a DC resonator suffers from unwanted...
-
Cross-talk Between the Heart and Arteries in Older 65+ Adults
PublikacjaRegulatory synchronization between the heart and the arterial walls is essential for optimal blood delivery to tissues. We investigated functional coherence between heart rhythm and aortic wall compliance in 30 volunteers aged 65 – 74. ECG and carotid and iliac pulse-wave were recorded and digitized at 2 kHz. Carotid-femoral pulse-wave transit time (cfTT) which reflex aortic compliance was assessed using the intersecting tangent...
-
Voice command recognition using hybrid genetic algorithm
PublikacjaAbstract: Speech recognition is a process of converting the acoustic signal into a set of words, whereas voice command recognition consists in the correct identification of voice commands, usually single words. Voice command recognition systems are widely used in the military, control systems, electronic devices, such as cellular phones, or by people with disabilities (e.g., for controlling a wheelchair or operating a computer...
-
Preparation of platinum modified titanium dioxide nanoparticles with the use of laser ablation in water
PublikacjaWe report on the preparation method of nanocrystalline titanium dioxide modified with platinum by using nanosecond laser ablation in liquid (LAL). Titania in the form of anatase crystals has been prepared in a two-stage process. Initially, irradiation by laser beam of a titanium metal plate fixed in a glass container filled with deionized water was conducted. After that, the ablation process was continued, with the use of a platinum...
-
Evolution of the nanostructure of Pt and Pt–Co polymer electrolyte membrane fuel cell electrocatalysts at successive degradation stages probed by X-ray photoemission
PublikacjaWe present a set of XPS (X-ray photoemission spectroscopy) measurements and detailed data-analysis of electrodes for polymer electrolyte membrane fuel cell (PEMFC) based on carbon supported catalysts (Pt and Pt–Co) subjected to a step-like potential cycling (accelerated degradation test). The results of the measurements complete and corroborate parallel TEM (transmission electron microscopy), XRD (X-ray diffraction) and XAS (X-ray...
-
Model Predictive Super-Twisting Sliding Mode Control for An Autonomous Surface Vehicle
PublikacjaThis paper presents a new robust Model Predictive Control (MPC) algorithm for trajectory tracking of an Autonomous Surface Vehicle (ASV) in presence of the time-varying external disturbances including winds, waves and ocean currents as well as dynamical uncertainties. For fulfilling the robustness property, a sliding mode control-based procedure for designing of MPC and a super-twisting term are adopted. The MPC algorithm has been...
-
Pre-swirl energy saving device in marine application
PublikacjaThis paper covers topics of energy saving device (ESD) with application to marine propulsors. The form of ESD, considered in this paper, consists of fixed lifting foils mounted in front of the screw propeller (the pre-swirl stator/guide vanes). An algorithm for designing propulsion systems, consisting of guide vanes and screw propeller, is presented. The proposed method relies on hybrid lifting line (guide vanes)-lifting surface...
-
Displacement piles - classification and methods for the calculation of bearing capacity.
PublikacjaDisplacement piles belong to a group of technologies whose main idea is to install or make a pile without extracting ground material. According to definition, contained in PN-EN:1997-1:2008, displacement piles should be considered as driven, pressed in using vibrators and made with the use of spread augers. The classification of piles used so far with regard to the technology of execution is modified. An additional element is the...
-
Hierarchical dissolved oxygen control for activated sludge processes
PublikacjaA hierarchical controller for tracking the dissolved oxygen reference trajectory in activated sludge processes is proposed and investigated. The removal of nitrogen and phosphorous from wastewater is considered. Typically, an aeration system itself is a complicated hybrid nonlinear dynamical system with faster dynamics compared to the internal dynamics of the dissolved oxygen in a biological reactor. It is a common approach to...
-
On the generalized model of shell structures with functional cross-sections
PublikacjaIn the present study, a single general formulation has been presented for the analysis of various shell-shaped structures. The proposed model is comprehensive and a variety of theories can be used based on it. The cross-section of the shell structure can be arbitrarily analyzed with the presented equations. In other words, various types of shell structures, including cylindrical, conical, spherical, elliptical, hyperbolic, parabolic,...
-
Estimation of the Regenerative Braking Process Efficiency in Electric Vehicles
PublikacjaIn electric and hybrid vehicles, it is possible to recover energy from the braking process and reuse it to drive the vehicle using the batteries installed on-board. In the conditions of city traffic, the energy dissipated in the braking process constitutes a very large share of the total resistance to vehicle motion. Efficient use of the energy from the braking process enables a significant reduction of fuel and electricity consumption...
-
EM-driven topology evolution for bandwidth enhancement of hybrid quadrature patch couplers
PublikacjaA broad operational bandwidth is one of the key performance figures of hybrid patch couplers. Due to the lack of systematic design procedures, bandwidth enhancement is normally obtained through manual modifications of the structure geometry. In this work, an optimization-based topology evolution for EM-driven design of patch couplers with enhanced bandwidth has been proposed. The method exploits a novel spline-based EM model where...
-
Potential reduction of traffic noise by the means of increased fleet of electric vehicles using a combination of low-noise tyres and low-noise road surfaces
PublikacjaIn the future, the number of zero-emission vehicles like electric and plug-in hybrid vehicles (in electric mode) is expected to be a substantial part of the vehicle fleet. In Norway, such vehicles already account for approximately 20 % of all new cars sold. Since these vehicles emit negligible noise related to the power-train, the tyre/road noise is the dominating noise source. In the LEO project, tyres designed for such cars have...
-
Resonance Frequency Calculation of a Multilayer and Multipatch Spherical Microstrip Structure Using a Hybrid Technique
PublikacjaThis communication offers a rigorous analysis of the resonance frequency problem of a spherical microstrip structure mounted on a multilayer, dielectric-coated metallic sphere, with an electrically small radius. The structure consists of single or multiple metallic patches with arbitrary shapes. A full-wave analysis is employed with the use of proposed hybrid approach, combining the finite-difference technique with a spectral domain...
-
Functionalized Peptide Fibrils as a Scaffold for Active Substances in Wound Healing
PublikacjaTechnological developments in the field of biologically active peptide applications in medicine have increased the need for new methods for peptide delivery. The disadvantage of peptides as drugs is their low biological stability. Recently, great attention has been paid to self-assembling peptides that can form fibrils. Such a formulation makes bioactive peptides more resistant to enzymatic degradation and druggable. Peptide fibrils...
-
Optimization of hybrid parallel application execution in heterogeneous high performance computing systems considering execution time and power consumption
PublikacjaMany important computational problems require utilization of high performance computing (HPC) systems that consist of multi-level structures combining higher and higher numbers of devices with various characteristics. Utilizing full power of such systems requires programming parallel applications that are hybrid in two meanings: they can utilize parallelism on multiple levels at the same time and combine together programming interfaces...
-
Three-dimensional numerical investigation of hybrid nanofluids in chain microchannel under electrohydrodynamic actuator
PublikacjaEnergy efficiency enhancement methods have received considerable attentionwithin the industry and scientific community, owing to the rising concern ofglobal energy sustainability. The present article attempts to scrutinize the effectsof electrohydrodynamics and nanofluids on the rate of heat transfer and fluidflow in the 3-D chain microchannels. Improved heat exchangers (e.g., chainmicrochannel) would have a key role in increasing...
-
Analysis of the regenerative braking process for the urban traffic conditions
PublikacjaIn a regular drive system, with an internal combustion engine, vehicle braking is connected with the unproductive dissipation of kinetic and potential energy accumulated in the mass of the vehicle into the environment. This energy can constitute up to 70% of the energy used to drive a vehicle under urban conditions. Its recovery and reuse is one of the basic advantages of hybrid and electric vehicles. Modern traffic management...
-
Optimisation of cooperation of hybrid renewable energy sources with hydrogen energy storage toward the lowest net present cost
PublikacjaThe paper presents the results of a technical and economic analysis of the power supply for a model industrial facility based on intermittent renewable energy sources in the form of wind turbines and photovoltaic modules, supplemented with hydrogen energy storage. The adopted power supply strategy assumed the maximisation of self-consumption of self-produced electricity. Six variants were considered, including two with an energy...
-
A Model of Thermal Energy Storage According to the Convention of Bond Graphs (BG) and State Equations (SE)
PublikacjaThe main advantage of the use of the Bond Graphs method and State Equations for modeling energy systems with a complex structure (marine power plants, hybrid vehicles, etc.) is the ability to model the system components of different physical nature using identical theoretical basis. The paper presents a method of modeling thermal energy storage, which is in line with basic BG theory. Critical comments have been put forward concerning...
-
Model-based testing for execution algorithms in the simulation of cyber-physical systems
PublikacjaThe understanding of simulation semantics of a hybrid system is a challenge for computational engineers as it requires expertise in computer science, engineering, numerical methods, and mathematics at once. The testing methods for the execution of a simulation are being researched but not yet applied on the industrial level. Consequently, the semantics of the simulation becomes a critical artifact in the system development process....
-
Inverse modeling for fast design optimization of small-size rat-race couplers incorporating compact cells
PublikacjaIn the paper, a framework for computationally-efficient design optimization of compact rat-race couplers (RRCs) is discussed. A class of hybrid RRCs with variable operating conditions is investigated, whose size reduction is obtained by replacing ordinary transmission lines with compact microstrip resonant cells (CMRCs). Our approach employs a bottom-up design strategy leading to the development of compact RRCs through rapid design...
-
Transient modeling in common DC link of power converters
PublikacjaПредмет исследования. Представлена математическая модель силовых преобразователей электропривода, питающихся от общего звена постоянного тока, на примере тяговых электроприводов карьерного самосвала БЕЛАЗ-90 мощностью 280 кВт. Модель выполнена в пакете MATLAB/Simulink. Новизна предложенной модели заключается в применении новой топологии силовой схемы для исследования работы двух инверторов, под- ключенных к одному звену постоянного...
-
Techno-economic assessment of cooperation of hybrid renewable energy sources with hydrogen storage
PublikacjaThe paper presents a technical and economic analysis of the power supply for a model industrial facility with the use of the most promising renewable energy sources (RES), supported by a hydrogen energy storage. This scenario was compared with the variants of supplying the facility directly from the grid and from RES without energy storage. A strategy was proposed for powering the plant aimed at maximising self-consumption of self-generated...
-
Building Project and Project Team Characteristics For Creating Hybrid Management Processes
PublikacjaThis paper introduces a method of building the characteristic of Software Development Project. Project characteristic is determined on the basis of several factors such as the complexity of Software Development Project and Project Team, results of historical projects and information on processes and methodologies, which are implemented in analyzed organizations. Information on project complexity can be applied to many different...
-
Systematic Management of Simulation State for Multi-Branch Simulations in Simulink
PublikacjaSystematic simulation is a technique related and motivated by the formal analysis of hybrid dynamic systems. It combines the exhaustive and conservative nature of traditional model checking with numerical simulation for providing efficient algorithms to manage simulations. Multi-branch simulation is the concept advancing simulation efficiency by reducing the number of state transitions. This paper introduces an approach to implement...
-
VIBRATION SURVEILLANCE DURING MILLING OF FLEXIBLE DETAILS WITH A USE OF THE ACTIVE OPTIMAL CONTROL
PublikacjaThe main goal of modern machining operations is to achieve increasingly better performance. High Speed Machining and/or High Performance Cutting, despite a lot of advantages, have also some drawbacks, for example, a possibility of losing stability and development of self-excited chatter vibration. This paper presents an approach of vibration surveillance during high speed milling with a use of active optimal control. Non-stationary...