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Wyniki wyszukiwania dla: shape function
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Heat exchange enhancement of jet impingement cooling with the novel humped-cone heat sink
PublikacjaJet impingement cooling technology is applicable to control temperature of devices, where very high heat flux is generated within a small area. This paper is about the improvement of the jet impingement cooling efficiency by the heat sink geometry modification. Two reference cases were sourced from the literature – flat heat sink and modified one with cone in the jet stagnation region. Such a change improves cooling capability...
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A Numerical Study on Baseline-Free Damage Detection Using Frequency Steerable Acoustic Transducers
PublikacjaIn structural health monitoring (SHM) a considerable amount of damage detection algorithms based on guided waves (GW) have been developed. Most of them rely on extensive transducer networks, besides preliminary reference measurements of the structures. This originated a growing demand for hardware simplification and cost reduction of the wave-based SHM methods, driving the conception of new solutions enabling both: the reduction...
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Clays as Inhibitors of Polyurethane Foams’ Flammability
PublikacjaPolyurethanes are a very important group of polymers with an extensive range of applications in different branches of industry. In the form of foams, they are mainly used in bedding, furniture, building, construction, and automotive sectors. Due to human safety reasons, these applications require an appropriate level of flame retardance, often required by various law regulations. Nevertheless, without the proper modifications,...
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DETERMINATION OF THE AERODYNAMIC DRAG OF PNEUMATIC LIFE RAFTS AS A FACTOR FOR INCREASING THE RELIABILITY OF RESCUE OPERATIONS
PublikacjaEnsuring the safety of ship crews at sea is of the utmost importance. Life rafts are one of the basic components of any seagoing vessel and ensuring their stability is an important component of maritime research. This study concerns the determination of the aerodynamic drag coefficients of pneumatic life rafts in a full range of wind speed and directions. The drag coefficients are based on full-scale experimental studies and numerical...
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Deformable model of a butterfly in motion on the example of Attacus atlas
PublikacjaInsect wings can undergo significant chordwise (camber) as well as spanwise (twist) deformation during flapping flight but the effect of these deformations is not well understood. The shape and size of butterfly wings leads to particularly large wing deformations, making them an ideal test case for investigation of these effects. High-speed videogrammetry was used to capture the wing kinematics and deformations. The movements of...
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Morphology Regulation Mechanism and Enhancement of Photocatalytic Performance of BiOX (X = Cl, Br, I) via Mannitol-Assisted Synthesis
PublikacjaBiOX (X = Cl, Br, I) photocatalysts with dominant (110) facets were synthesized via a mannitol-assisted solvothermal method. This is the first report on the exposed (110) facets-, size-, and defects-controlled synthesis of BiOX achieved by solvothermal synthesis with mannitol. This polyol alcohol acted simultaneously as a solvent, capping agent, and/or soft template. The mannitol concentration on the new photocatalysts morphology...
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Specialist Pavilion Hospitals Of West Prussia In The 19th Century – Evolution Of The Idea
PublikacjaThe size and shape of the largest pavilion hospitals established in West Prussia in the 19th century changed along with the advancing technical and medical knowledge, the progress of ideas regarding modern society, architectural patterns, and the needs for which the hospitals were built. Apart from the medical treatment section, there were administrative, social and technical facilities, all constituting parts of the complex. The...
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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...
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Nanostructuring of thin Au films deposited on ordered Ti templates for applications in SERS
PublikacjaIn this work the results on thermal nanostructuring of the Au films on Ti templates as well as morphology and optical properties of the obtained structures are reported. The bimetal nanostructures are fabricated in a multi-step process. First, the titania nanotubes are produced on the surface of Ti foil by anodization in an ethylene glycol-water solution containing fluoride ions. This is followed by chemical etching in oxalic acid...
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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...
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Effect of alkyl sulfate on the phase behavior of microemulsions stabilized with monoacylglycerols
PublikacjaIn this study the effect of an anionic surfactant (sodium dodecyl sulfate SDS) and oils (hydrocarbons: C12-C16) on the formation and phase behavior of the systems of oil/monoacylglycerols (MAG):SDS/propylene glycol/water has been investigated. The effects of the surfactant mixture on the phase behavior and the concentrationof water or oil in the systems were studied at three temperatures (50, 55, 60 C). Electrical conductivity...
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Enhancing Seismic Performance of Semi-rigid Connection Using Shape Memory Alloy Bolts Considering Nonlinear Soil–Structure Interaction
PublikacjaSteel Moment-Resisting Frames (SMRFs) have their lateral resistance for their rigid connections, while real conditions have shown that the rigidity of a connection depends on the bolts and the end-plate thickness, which may not provide the assumed rigidity in design process. In this research, the main goal is to enhance the semi-rigid connections using shape memory alloy (SMA) bolts and explore their effects on the seismic limit-state...
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Superconductivity in a breathing kagome metals ROs2 (R = Sc, Y, Lu)
PublikacjaWe have successfully synthesized three osmium-based hexagonal Laves compounds ROs2 (R = Sc, Y, Lu), and discussed their physical properties. LeBail refinement of pXRD data confirms that all compounds crystallize in the hexagonal centrosymmetric MgZn2- type structure (P63/mmc, No. 194). The refined lattice parameters are a = b = 5.1791(1) Å and c = 8.4841(2) Å for ScOs2, a = b = 5.2571(3) Å and c = 8.6613(2) Å for LuOs2 and a =...
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MOF/TiO2 erythrocyte-like heterostructures decorated by noble metals for use in hydrogen photogeneration and pollutant photodegradation
PublikacjaVarious metal–organic framework (MOF)/TiO2 heterostructures can be obtained by the partial hydrolysis or calcination of Ti-based MOFs. By adjusting the hydrolysis and calcination steps of NH2-MIL-125 (Ti), a novel photoactive material composed of a MOF (NH2-MIL-125 (Ti)) and TiO2, with a unique “erythrocyte” shape, was developed. Furthermore, modification of the composition prepared by the partial hydrolysis of NH2- MIL-125 (Ti)...
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Protection and renovation of public areas in a modernist city: the case of three streets in the historic City Centre of Gdynia
PublikacjaThis article concerns issues related to the preservation and restoration of public space in Gdynia’s city centre, which was designed and built mainly in the 1920s and 1930s. In 2007, a major part of the city centre was entered into the register of monuments asa historic complex of urban architecture. Moreover, in 2015, the area was declared a Monument of History. Protection of a complex of urban architecture covers not only the...
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Morphology and internal structure of small-scale washovers formed in the coastal zone of the semi-enclosed tideless basin, Gulf of Gdańsk, Baltic Sea
PublikacjaThis study explores the morphological features and internal structure of small-scale washovers along the southeastern Baltic Sea coast, providing insights into these most widespread yet often neglected deposits in the recent research of geomorphological and sedimentary record of storm surges. A 15-year-long record of morphological changes of the coast was acquired from regional orthophotos to analyse their geometry and spatial...
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New synthesis route of highly porous InxCo4Sb12 with strongly reduced thermal conductivity
PublikacjaHighly porous, In-filled CoSb3 skutterudite materials with an attractive thermoelectric figure of merit (ZT * 1) and corresponding dense samples were fabricated through the cost-effective method of reduction in oxides in dry hydrogen and the pulsed electric current sintering (PECS) method, respectively. The reduction process was described in detail using in situ thermogravimetric analysis of Co2O3, Sb2O3 and In(NO3)35H2O separately...
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Planning Around Polarisation: Components of Finding Common Ground Based on Regeneration Projects in London and Gdańsk
PublikacjaVarious forms of public participation in urban design and planning—as presented and discussed in literature—have recently been challenged by the needs and expectations of different stakeholders, including those coming from the private sector. This comes with a redefinition of the public good and the roles and responsibilities of municipal authorities in post‐liberal times. As a result, contemporary participatory processes need...
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Experimental and numerical analysis of the pyrolysis dynamics of a single wood particle: presentation of the radiographic technique
PublikacjaPyrolysis is an oxygen-free process for the thermal decomposition of raw materials. The heat conduction and flow of pyrolysis products (i.e., the gas fraction and liquid vapour generated during pyrolysis) influence the process and products. In this work, the influence of the orientation of wooden particle fibres with respect to the direction of the heat source on the dynamics of the process was investigated, where there were two...
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Design and Optimization of Metamaterial-based Highly-isolated MIMO Antenna with High Gain and Beam Tilting Ability for 5G Millimeter Wave Applications
PublikacjaThis paper presents a wideband multiple-input multiple-output (MIMO) antenna with high gain and isolation, as well as beam tilting capability, for 5G millimeter wave (MMW) applications. A single bow-tie antenna fed by a substrate-integrated waveguide (SIW) is proposed to cover the 28 GHz band (26.5–29.5 GHz) with a maximum gain of 6.35 dB. To enhance the gain, H-shaped metamaterial (MM)-based components are incorporated into the...
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Design of a Shape-Memory-Alloy-Based Carangiform Robotic Fishtail with Improved Forward Thrust
PublikacjaShape memory alloys (SMAs) have become the most common choice for the development of mini- and micro-type soft bio-inspired robots due to their high power-to-weight ratio, ability to be installed and operated in limited space, silent and vibration-free operation, biocompatibility, and corrosion resistance properties. Moreover, SMA spring-type actuators are used for developing different continuum robots, exhibiting high degrees...
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Elastic scattering of electrons from chloroform
PublikacjaWe present experimental and theoretical cross sections for elastic electron scattering from CHCl3. This is an important target because of its relevance to environmental chemistry and the plasma etching industry as a source of chlorine radicals. The experimental results were obtained at incident electron energies ranging from 0.5 to 800 eV in the 10deg-130deg scattering angle range. Theoretically, the scattering cross sections in...
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The Influence of the Electrodeposition Parameters on the Properties of Mn-Co-Based Nanofilms as Anode Materials for Alkaline Electrolysers
PublikacjaIn this work, the influence of the synthesis conditions on the structure, morphology, and electrocatalytic performance for the oxygen evolution reaction (OER) of Mn-Co-based films is studied. For this purpose, Mn-Co nanofilm is electrochemically synthesised in a one-step process on nickel foam in the presence of metal nitrates without any additives. The possible mechanism of the synthesis is proposed. The morphology and structure...
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OPTIMAL FARM SIZE AND EFFECTIVENESS OF AGRICULTURE IN THE EU: THE CASE OF WHEAT YIELDS
PublikacjaThe article concentrates on the relationship between the size of a farm and its efficiency in relation to wheat production in the European Union (EU). The issue is not new, however fundamental from the point of view of the agricultural policy, as the appropriate shape of the agrarian structure affects the economic rationality in agriculture and significantly improves the productivity. We analysed data for the period between 2004...
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Design and computational fluid dynamics analysis of the last stage of innovative gas-steam turbine
PublikacjaResearch regarding blade design and analysis of flow has been attracting interest for over a century. Meanwhile new concepts and design approaches were created and improved. Advancements in information technologies allowed to introduce computational fluid dynamics and computational flow mechanics. Currently a combination of mentioned methods is used for the design of turbine blades. These methods enabled us to improve flow efficiency...
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Simulation of unsteady flow over floodplain using the diffusive wave equation and the modified finite element method
PublikacjaWe consider solution of 2D nonlinear diffusive wave equation in a domain temporarily covered by a layer of water. A modified finite element method with triangular elements and linear shape functions is used for spatial discretization. The proposed modification refers to the procedure of spatial integration and leads to a more general algorithm involving a weighting parameter. The standard finite element method and the finite difference...
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The analysis of the influence of the corrosion protection method of selected steel elements on the steel structure life cycle costs
PublikacjaSteel products are widely used in the construction for the performance of essential and additional elements of engineering structures. They are characterized by high tensile strength, compression and bending, the structure homogeneity, the possibility of assembly regardless of the season and climatic conditions, ease of processing and the possibility of almost any shape. The main disadvantage of steel structures is their high susceptibility...
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Colour Terms in Five Linguistic Images of the World: The Semantic Perspective
PublikacjaSocial and cultural factors shape the linguistic perception of colour. At the same time, colour terms co-create the linguistic image of the world, which allows us to interpret reality and profile our statements and beliefs. This paper presents six basic colour terms: white, black, red, green, yellow, and blue (both as adjectives and as nouns) in the five different linguistic images of the world of the following languages: English,...
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The experience of movement in orbital space architecture: A narrative of weightlessness
PublikacjaBased upon a combination of architectural theories, the knowledge of space environment, and psychology of isolated and confined environments, this qualitative research aims to study orbital space settlement in a way to get the built space congenial to the human experience of movement. In this sense, sensors, self-propulsion or mechanical actuators, the inhabitant’s mental and visual capacity for movement, as well as the represented...
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Sustainability of Civil Structures through the Application of Smart Materials: A Review
PublikacjaEvery year, structural flaws or breakdowns cause thousands of people to be harmed and cost billions of dollars owing to the limitations of design methods and materials to withstand extreme earthquakes. Since earthquakes have a significant effect on sustainability factors, there is a contradiction between these constraints and the growing need for more sustainable structures. There has been a significant attempt to circumvent...
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Structural evaluation of percolating, self-healing polyurethane–polycaprolactone blends doped with metallic, ferromagnetic, and modified graphene fillers
PublikacjaComposites with differently shaped micro- and nanofillers show various, unique thermal, and physicochemical properties when mixed with carefully chosen polymer matrix. Selected composition holds strategic value in achieving desired properties that is biodegradability, thermoelectric conductivity, and shape memory for organic coating. The main aim of this work is to briefly examine structural changes after reaching percolation...
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Multi-fidelity robust aerodynamic design optimization under mixed uncertainty
PublikacjaThe objective of this paper is to present a robust optimization algorithm for computationally efficient airfoil design under mixed (inherent and epistemic) uncertainty using a multi-fidelity approach. This algorithm exploits stochastic expansions derived from the Non-Intrusive Polynomial Chaos (NIPC) technique to create surrogate models utilized in the optimization process. A combined NIPC expansion approach is used, where both...
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Electron scattering from 2-methyl–1,3-butadiene,C5H8, molecules: Role of methylation
PublikacjaWe report cross-section results from experimental and theoretical investigations into electron collisions with the 2-methyl–1,3-butadiene [C5H8] molecule. The current results are compared with our previous results for the 1,3-butadiene [C4H6] molecule, a structural homologue of 2-methyl–1,3-butadiene, to investigate how the methylation (the substitution of hydrogen atom by a methyl group) affects the shape and/or magnitude of the...
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Mobile inventory system for hydrotechnical objects using data from multiple sensors operating simultaneously
PublikacjaThe knowledge of the location, shape and other characteristics of spatial objects in the coastal areas has a significant impact on the functioning of ports, shipyards, and other water-infrastructure facilities, both offshore and inland. Therefore, measurements are taken of the underwater part of the waterside zone, which means the bottom of water and other underwater objects (e.g. breakwaters, docks, etc.), and objects above the...
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Algorithm for Automatic Wear Estimation of Railway Contact Strips Based on 3D Scanning Results
PublikacjaElectric rail vehicles use current collection system which consists of overhead contact line and a current collector (pantograph) mounted on the roof of a vehicle. A pantograph is equipped with contact strips, which slide along the contact wire, ensuring steady electric contact. Contact strips are made of carbon layer, fixed to an aluminum carrier. The carbon layer wears down due to friction. Using overly worn contact strips increases...
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Electronic conductivity in the SiO2-PbO-Fe2O3 glass containing magnetic nanostructures
PublikacjaThe linear impedance spectra of iron–silicate–lead glass samples were measured in the frequency range from 1 MHz to 1 MHz and in the temperature range from 153 K to 423 K. The structure was investigated by means of XRD and atomic force microscopy. Local electrical and magnetic properties of the samples were tested with the aid of electrostatic force microscopy (EFM) and magnetic force microscopy (MFM). The obtained results show...
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Chromatographic behavior of a new hybrid type RP material containing silica bonded 1,3-alternate 25,27-bis-[cyanopropyloxy]-26,28-bis-[3-propyloxy]-calix[4]arene
PublikacjaA novel 1,3-alternate 25,27-bis-[cyanopropyloxy]-26,28-bis-[3-propyloxy]-calix[4]arene-bonded silica gel stationary phase (CalixPrCN) was prepared and it's structure was confirmed by ATR-FTIR spectroscopy and elemental analysis. The CalixPrCN phase was characterized in terms of their surface coverage, hydrophobic selectivity, aromatic selectivity, shape selectivity, hydrogen bonding capacity, residue metal content, and silanol...
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Structure of Microemulsion Formulated with Monoacylglycerols in the Presence of Polyols and Ethanol
PublikacjaThe influence of polyols as cosurfactants (propylene glycol PG; glycerol G) and short chain alcohol as a cosolvent (ethanol EtOH) on the formation and solubilization capacity of the systems: hexadecane/monoacylglycerols (MAG)/polyol/water:EtOH, at 60C, was investigated. Electrical conductivity measurement, and the DSC method were applied to determine the structure and type of microemulsions formed. The dimension of the droplets...
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New Technologies Adoption and Diffusion Patterns in Developing Countries. An Empirical Study for the Period 2000-2011
PublikacjaIn recent years, enormous changes are noted worldwide when broad adoption of Information and Communication Technologies (ICT). These unique technologies – often perceived as economic development incentives – have a great ability to spread at high pace and low cost in world countries, bringing to people opportunities to contribute to economic development and growth. New Technologies play a special role in developing countries, where...
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Game theory-based virtual machine migration for energy sustainability in cloud data centers
PublikacjaAs the demand for cloud computing services increases, optimizing resource allocation and energy consumption has become a key factor in achieving sustainability in cloud environments. This paper presents a novel approach to address these challenges through an optimized virtual machine (VM) migration strategy that employs a game-theoretic approach based on particle swarm optimization (PSO) (PSO-GTA). The proposed approach leverages...
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Effect of the ex situ physical and in situ chemical modification of bacterial nanocellulose on mechanical properties in the context of its potential applications in heart valve design
PublikacjaBacterial nanocellulose (BNC) is a promising material for heart valve prostheses. However, its low strength properties limit its applicability in cardiovascular surgery. To overcome these limitations, the mechanical properties of BNC can be improved through modifications. The aim of the research was to investigate the extent to which the mechanical properties of BNC can be altered by modifying its structure during its production...
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Oxide nanoparticle exsolution in Lu-doped (Ba,La)CoO3
PublikacjaThis study investigated Lu doping of Ba0.5La0.5CoO3 and its influence on the exsolution of oxide nanoparticles (NPs). As a result of Lu doping, we observed the phase segregation into the main Ba0.4La0.6Co0.85Lu0.15O3 (BLCO–Lu) phase and the secondary Ba0.85La0.15Co0.75Lu0.25O3 (BCO–Lu) phase. We noticed the exsolution of BCO–Lu nanoparticles on the main BLCO–Lu phase. Moreover, the BLCO–Lu phase exsolved in the form of nanoparticles...
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Corrosion damage identification based on the symmetry of propagating wavefield measured by a circular array of piezoelectric transducers: Theoretical, experimental and numerical studies
PublikacjaThe article investigates the results obtained from numerical simulations and experimental tests concerning the propagation of guided waves in corroded steel plates. Developing innovative methodologies for assessing corrosion-induced degradation is crucial for accurately diagnosing offshore and ship structures exposed to harsh environmental conditions. The main aim of the research is to analyze how surface irregularities affect...
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Broad Stopband, Low-Loss, and Ultra-Compact Dual-Mode Bandpass Filter Based on HMSIRC
PublikacjaIn this investigation, an ultra-compact dual-mode bandpass filter (BPF) with a wide stopband re-sponse is realized by using a half-mode substrate-integrated rectangular cavity (HMSIRC). The HMSIRC resonator is designed with a cavity that is rectangular in shape and has metallic vias along three of the sides. The fourth side is open-ended and contains microstrip feed lines. For the purpose of constructing a magnetic wall, a rectangular...
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The In-House Method of Manufacturing a Low-Cost Heat Pipe with Specified Thermophysical Properties and Geometry
PublikacjaVarious types of heat pipes are available to purchase off the shelf, from various manufacturers, but most of them have strictly defined geometry and technical parameters. However, when there is a need to use a heat pipe (HP) with an unusual size and shape or working conditions other than the standard ones, it becomes very costly to order them from manufacturers, especially in small quantities, and only a few producers are willing...
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The significance of institutions' potential to increase Youth civic participation – case study of the South Baltic Youth Core Groups Network Project
PublikacjaYoung people are a very important group of modern societies, they will replace the currently ruling generation and will shape our common future. Due to that, young people have become the relevant target of national and international policy and science researches. Youth civic participation is a key aspect of the development of a society and should be shaped by effective youth policy at the national and international levels. This...
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Structural evaluation of percolating, self-healing polyurethane–polycaprolactone blends doped with metallic, ferromagnetic, and modified graphene fillers
PublikacjaComposites with differently shaped micro- and nanofillers show various, unique thermal, and physicochemical properties when mixed with carefully chosen polymer matrix. Selected composition holds strategic value in achieving desired properties that is biodegradability, thermoelectric conductivity, and shape memory for organic coating. The main aim of this work is to briefly examine structural changes after reaching percolation threshold...
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Fast Multi-Objective Aerodynamic Optimization Using Sequential Domain Patching and Multifidelity Models
PublikacjaExploration of design tradeoffs for aerodynamic surfaces requires solving of multi-objective optimization (MOO) problems. The major bottleneck here is the time-consuming evaluations of the computational fluid dynamics (CFD) model used to capture the nonlinear physics involved in designing aerodynamic surfaces. This, in conjunction with a large number of simulations necessary to yield a set of designs representing the best possible...
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Curved Surface Minijet Impingement Phenomena Analysed with ζ-f Turbulence Model
PublikacjaThe jet impingement phenomenon plays an important role among the heat transfer intensification methods. Very often its application and analyses refer to simple flat surfaces, while there is a lack of information in the literature for cases addressing curved surfaces. In the present work, the single jet impingement on the non-flat (concave and convex) surface is studied for a wide range of geometries, which originate from the mini-jet...
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PARAMETERS OF THE ELECTROPHORETIC DEPOSITION PROCESS AND ITS INFLUENCE ON THE MORPHOLOGY OF HYDROXYAPATITE COATINGS. REVIEW
PublikacjaMetallic materials intended for bone implants should exhibit not only appropriate mechanical properties, but also high biocompatibility. The surface treatment modifications, for example acidic treatment, laser treatment, ion implantation and deposition of highly biocompatible coatings, are practiced. One of the most popular methods of surface modification is to deposit hydroxyapatite (HAp) coatings. HAp naturally occurs in human...