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In-situ optical diagnostics of boron-doped diamond films growth
PublicationInterferometry is a desirable method for in-situ measurement of thin, dielectric film growth, as it don't modify conditions of film deposition. Here we present interferometrical measurements of thickness of doped diamond films during Chemical Vapor Deposition (CVD) process. For this purpose we used a semiconductor laser with a 405nm wavelength. Additional ex-situ measurement using spectral interferometry and ellipsometry...
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Detection of damages in a rivetted plate
PublicationThe paper presents the results of damage detection in a riveted aluminium plate. The detection method has been based on Lamb wave propagation. The plate has been analysed numerically and experimentally. Numerical calculations have been carried out by the use of the time-domain spectral finite element method, while for the experimental analysis laser scanning Doppler vibrometry (LSDV) has been utilised. The panel has been excited...
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Lamb wave propagation in a single lap adhesive joint
PublicationThe aim of the paper is the analysis of Lamb wave propagation in adhesive joints. The research was performed on a single lap adhesive joint of two steel plates. Two types of joints, namely an intact and with defect were considered. In experimental investigations the condition assessment of the joint was performed with the use of antisymmetric Lamb waves excited by a plate piezo actuators and measured by a laser vibrometer. Numeri-cal...
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Generalized access control in hierarchical computer network
PublicationThe paper presents the design of the security layer for a distributed system located in the multizone hierarchical computer network. Depending on the zone from which a client’s request comes to the system and the type of the request, it will be either authorized or rejected. There is one common layer for the access to all the business services and interactions between them. Unlike the commonly used RBAC model, this system enforces...
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High temperature corrosion of evaporator tubes with thermal sprayed coatings
PublicationDegradation examinations of outer surface of low-emission steam boiler evaporator tubes are presented in the paper. Metallographic evaluation of scale morphology, its micro sites chemical composition analysis and distribution of elements on cross sections have been performed. Water-wall tubes were exposed in steam boiler for up to two years period. Common tubes made of 16Mo3 steel suffered sulphide and molten salts corrosions....
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Interaction of SrTi0.65Fe0.35O3-δ with LaNi0.6Fe0.4O3-δ, La0.6Sr0.4Co0.2Fe0.8O3-δ and Ce0.8Gd0.2O2-δ
PublicationIron doped strontium titanates SrTi1-xFexO3-δ are perovskites of versatile properties. They can be used in solid oxide fuel cells or high temperature oxygen sensors. Their reactivity with electrolyte materials, cathode buffer layer materials, other cathode materials or current collector layers has not been fully tested. In this study we use X-ray diffraction to check SrTi0.65Fe0.35O3-δ compatibility with Ce0.8Gd0.2O2-δ (used as...
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Evidence for solid state electrochemical degradation within a small molecule OLED
PublicationAcridone derivative have been synthesised and used as OLED (Organic Light Emitting Diode) emitters which were found to be electroactive. Electrochemical investigations showed a side reaction takes place inside an active layer which diminished the overall device efficiency. By using a dopant and host active layer architecture, the formation of the by product was removed. The by-product was identified as a σ-dimer formed inside an...
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Performance improvement of NN based RTLS by customization of NN structure - heuristic approach
PublicationThe purpose of this research is to improve performance of the Hybrid Scene Analysis – Neural Network indoor localization algorithm applied in Real-time Locating System, RTLS. A properly customized structure of Neural Network and training algorithms for specific operating environment will enhance the system’s performance in terms of localization accuracy and precision. Due to nonlinearity and model complexity, a heuristic analysis...
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Numerical Modeling of Cone Penetration Test in Slightly Overconsolidated Clay with Arbitrary Lagrangian-Eulerian Formulation
PublicationIn this paper the results of the cone penetration test (CPT) modeling with the arbitrary Lagrangian-Eulerian (ALE) formulation provided by Abaqus software package have been presented. The study compares the cone resistance and sleeve friction obtained in numerical analysis with values measured in soundings performed in the uniform layer of clayey soil in the Koszalin area. The clay layer was found to be slightly overconsolidated...
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Changes in conditions of acoustic wave propagation in the Gdansk deep as an effect of climate changes in the Baltic Sea region
PublicationThe article presents the results from a research project investigating acoustic climate changes in the Gdansk Deep based on data extending from 1902 to 2019. This part of the southern Gotland Basin, is rarely discussed in the scientific literature. The speed of sound in the seawater is a function of temperature, salinity, and depth. In such shallow sea as Baltic Sea, the impact of depth is not substantial. The other two factors...
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Detection of petroleum products using optical coherence tomography
PublicationIn this work, we present a novel method developed for the analysis of the properties of thin layers for detecting petroleum products on a water surface using a commercially available optical coherence tomography (OCT) system. The spectral density analysis of the signal from a spectroscopic OCT (S-OCT) enables us to perform the precision calculation of the thin layer thickness and other properties like homogeneity, and dispersion,...
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Nanotubular Ti Oxide Layers for Enhancement of Bone-Implant Bonding and Bioactivity
PublicationAbstrakt artykułu pt. ''Nanotubular Ti Oxide Layers for Enhancement of Bone-Implant Bonding and Bioactivity''. The paper describes techniques to improve the bioactivity of titanium and ehnahnce the bone-implant bonding ability by the electrochemical anodization to fabricate titania nanotubular oxide layer.
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Analiza przydatności różnych metod do pomiaru przemieszczeń i ugięcia dźwigarów oraz belek
PublicationPrzedstawiono nowoczesny sposób pomiarów przemieszczeń elementów poziomych obciążonych statycznie. Zaprezentowano ideę wykorzystania źródła lasera w prototypie urządzenia własnej koncepcji do pomiaru ugięcia belek wraz z analizą wyników w warunkach modelowych.
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Wpływ natężenia kawitacji na względną odporność kawitacyjną obrobionej laserowo stali 45
PublicationPrzedstawiono badania odporności kawitacyjnej stali 45 w początkowym okresie niszczenia po przetapianiu jej powierzchni wiązką lasera CO2 o mocy 6 kW. Stwierdzono spadek względnej odporności kawitacyjnej wraz ze wzrostem natężenia kawitacji.
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Numerical simulation of laminate composite specimens failure
PublicationThis work presents some numerical results concerning simulation of failure of laminate composite specimens. In the article two tests to determine ultimate strength in an orthotropic layer, are considered: tension (TT1) and compression (TC1) test. The outcome is compared with experimental data provided by [9,10].
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Comparison of stump closure techniques during laparoscopic appendectomies for complicated appendicitis – results from Pol-LA (Polish laparoscopic appendectomy) multicenter large cohort study
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Progress in module design for membrane distillation
PublicationThere have been tremendous advances in membrane distillation (MD) since the concept was introduced in 1961: new membrane designs and process configurations have emerged, and its commercial viability has been evaluated in several pilot-scale studies. However, its high energy consumption has hindered its commercialization. One of the most promising ways to overcome this obstacle is to develop more energy-efficient membrane modules....
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CGO FILMS ON YSZ ELECTROLYTE FABRICATED BY SPRAY PYROLYSIS FOR SOFC
PublicationINTRODUCTION Solid oxide fuel cells are one of the fastest developing energy converters. The advancement introduced by research community provides steady state progress is stability and performance of the fuel cells. Significant influence on the cell’s performance and stability is related to cell design. The simplest design just consists of an anode, a solid electrolyte and a cathode. However, in order to improve the properties,...
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Artificial neural network prophecy of ion exchange process for Cu (II) eradication from acid mine drainage
PublicationThe removal of heavy metal ions from wastewater was found to be significant when the cation exchange procedure was used effectively. The model of the cation exchange process was built using an artificial neural network (ANN). The acid mine drainage waste’s Cu(II) ion was removed using Indion 730 cation exchange resin. Experimental data from 252 cycles were recorded. In a column study, 252 experimental observations validated the...
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Optical sensor of a person sitting on a chair and dressed in multi-layered clothes vital signs monitoring
PublicationAn optoelectronic device enhancing a smart chair functionality is presented in the paper. Its essential purpose is a detection of a sitting person presence on the chair by means of detecting the vital signs. Additionally, it could be used for determining of clothes layer parameters useful in adjusting a system of a capacitive electrocardiography.
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Multi-instrument analysis of L-band amplitude scintillation observed over the Eastern Arabian Peninsula
PublicationThe study of scintillation-causing ionospheric irregularities is important to mitigate their effects on satellite communications. It is also important due to the spatial and temporal variability of these irregularities, given that their characteristics differ from one region to another. This study investigates the spatial and temporal characteristics of L1 amplitude scintillation-causing ionospheric irregularities over the Eastern...
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Formation of bubbles from a single nucleation site.
PublicationPrzedstawiono wyniki systematycznych badań eksperymentalnych wrzenia wody destylowanej i metanolu z pojedynczego, sztucznego centrum nukleacji. Jako centra nukleacji służyły otwory wywiercone na czołowej powierzchni miedzianego pręta. Średnice otworów wynosiły: 0.25 mm, 0.60 mm oraz 1.0 mm. Do pomiaru częstotliwości odrywania się pęcherzyków zastosowano układ laser diodowy-fotodioda. Sygnał z fotodiody był rejestrowany za...
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Wave propagation in damage assessment of ground anchors
PublicationThe inspection possibilities of ground anchors are limited to destructive test such as pull-out test. Guided wave propagation gives an opportunity to develop an inspection system dedicated to determine the condition of inspected element without violation of their integrity. In this paper the experimental study on wave propagation in laboratory models of ground anchors are presented. Experiments were conducted for different bonding...
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ESTIMATION OF YOUNG`S MODULUS OF THE POROUS TITANIUM ALLOY WITH THE USE OF FEM PACKAGE
PublicationPorous structures made of metal or biopolymers with a structure similar in shape and mechanical properties to human bone can easily be produced by stereolithographic techniques, e.g. selective laser melting (SLM). Numerical methods, like Finite Element Method (FEM) have great potential in testing new scaffold designs, according to their mechanical properties before manufacturing, i.e. strength or stiffness. An example of such designs...
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3D Printing of Metallic Implants
PublicationThe fabrication of various elements, solid and open porous structures of stainless steel and Ti alloy is described. The process was started with the design of 3D models in CAD/CAM system. The 3D models were transformed into *.stl files and then the manufacturing process of the real structures by means of the selective laser melting with the SLM Realizer 100 3D printer was made. The paper shows the porous specimens made for possible...
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Investigations of the optical activity of nonlinear crystals by means of dual-wavelength polarimeter
PublicationA dual-wavelength method in high accuracy polarimetry has been successfully tested and applied to measure optical activity (OA) of nonlinear crystals. In proposed polarimetric scheme two neighboring semiconductor laser wavelengths (635 and 650 nm) are used, which increases number of parameters measured simultaneously and improves the data processing. By neglecting dispersion of eigen wave ellipticity in crystals, more efficient...
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Processing of Hydroacoustic and LiDAR Data for Three-dimensional Surface Reconstruction
PublicationThe technologies of sonar and laser scanning are commonly used for obtaining spatial information about underwater and over ground environments in the form of point clouds. Since this data model has known disadvantages, a more practical solution of visualising such data involves the creation of solid three-dimensional meshes composed of edges and facets. In this paper, several methods for 3D shape reconstruction of data obtained...
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Optymalizacja topologiczna części lotniczych
PublicationOstatnie 40 lat to ciągły rozwój przemysłu lotniczego, dzięki któremu możliwe jest wykonywanie bezpiecznych, szybkich oraz ekonomicznych lotów. Projektowanie i budowa nowoczesnych samolotów wymaga jednak wykorzystywania wysoko rozwiniętych metod oraz technologii, dzięki którym możliwe jest sprostanie stawianym przed nimi wymaganiom. EADS Innovation Works, jako organizacja badawczo-technologiczna, jest zaangażowana w rozwój oraz...
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Damage localisation in a stiffened plate structure using a propagating wave
PublicationThe paper presents an application of changes in propagating waves for damage detection in a stiffened aluminium plate. The experimental investigation was conducted on an aluminium plate with riveted two L-shape stiffeners. The wave has been excited with a piezoelectric transducer and measured with the Laser Scanning Doppler Vibrometer. Recorded signals were analysed using the special signal processing techniques developed for damage...
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Impact of cross-section centers estimation on the accuracy of the Point cloud spatial expansion using robust M-estimation and Monte Carlo simulation
PublicationThe point cloud spatial expansion (PCSE) method creates an alternative form of representing the shape of symmetrical objects and introduces additional descriptive geometric parameters. An important element of the procedure is determining the course of the axis of symmetry of cylindrical objects based on cross-sections of point clouds. Outliers occurring in laser measurements are of great importance in this case. In this study,...
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Study on Microstructure-Property Relationship of Inconel 617 Alloy/304L SS Steel Dissimilar Welds Joint
PublicationWelding of Inconel 617 (IN617) alloy and austenitic 304L SS steel has been attempted using the autogenous Laser Beam Welding (LBW) process. Characterization of dissimilar weldments was performed on either side of the fusion boundaries. The metallographic results showed that the inhomogeneous microstructure formation for weld metal contained columnar and cellular dendrites near the interface, whilst the columnar, cellular and equiaxed...
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Charakterystyka kawitacyjna laserowo obrabianych napoin Fe-Cr-Mn
PublicationPrzedstawiono badania odporności kawitacyjnej napoin Fe-Cr-Mn w dwóch przypadkach: bez dodatkowej obróbki powierzchniowej oraz po przetapianiu powierzchni napoiny wiązką lasera CO2 o mocy 1000W. Oceniano głębokość i stopień umocnienia warstwy wierzchniej.
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Zgred - Zgred Graph Editor
PublicationThe paper presents a graph editor that was developed as a supplementary tool for the Koala graph library. We discuss its requirements, design choices and main ideas behind the implementation. The later part of the paper is meant to be a brief user manual, as we go through the functionality provided by the editor
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Changes in conditions of acoustic wave propagation in the Gdansk deep as an effect of climate changes in the Baltic Sea region
PublicationThe article presents the results from a research project investigating acoustic climate changes in the Gdansk Deepbased on data extending from 1902 to 2019. This part of the southern Gotland Basin, is rarely discussed in thescientific literature.The speed of sound in the seawater is a function of temperature, salinity, and depth. In such shallow sea asBaltic Sea, the impact of depth is not substantial....
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Dissolution of Nb-doped hydroxyapatite prepared via low-temperature mechanochemical method: Spectroscopy studies
PublicationCalcium phosphate glass ceramics with nominal hydroxyapatite stoichiometry doped with niobium were synthesized using simple as well as low-temperature mechanochemical method and then in the form of compressed pellet were submitted to the static dissolution process in distilled water for one month. The results of structural analysis, performed mainly on the base of spectroscopic methods such as: infrared absorption spectroscopy,...
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The effect of multiaxial geocomposite reinforcement on fatigue performance and crack propagation delay in double-layered asphalt beams
PublicationThe presented study investigates the effect of a recently developed multiaxial geocomposite made of polypropylene geogrid and non-woven fabric on the delay of crack propagation, based on four-point bending tests of large asphalt concrete beams – both for reinforced and non-reinforced specimens. Several approaches are described in this study, including analysis of stiffness modulus decrease and analysis of crack propagation using...
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Evaluation of ASON/GMPLS Connection Control Servers Performance
PublicationPerformance aspects have always been very important in telecommunications, especially in control elements. That problem also regards ASON/GMLPS network, which is one of the propositions for Next Generation Network (NGN) transport stratum. In this paper we investigate performance of ASON/GMPLS Connection Control Servers (CCSs) in laboratory testbed, which architecture and operation are also described. In order to evaluate the performance...
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2-D constitutive equations for orthotropic Cosserat type laminated shells in finite element analysis
PublicationWe propose 2-D Cosserat type orthotropic constitutive equations for laminated shells for the purpose of initial failure estimation in a laminate layer. We use nonlinear 6-parameter shell theory with asymmetric membrane strain measures and Cosserat kinematics as the framework. This theory is specially dedicated to the analysis of irregular shells, inter alia, with orthogonal intersections, since it takes into account the drilling...
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Theoretical Model of Acoustic Wave Propagation in Shallow Water
PublicationThe work is devoted to the propagation of low frequency waves in a shallow sea. As a source of acoustic waves, underwater disturbances generated by ships were adopted. A specific feature of the propagation of acoustic waves in shallow water is the proximity of boundaries of the limiting media characterised by different impedance properties, which affects the acoustic field coming from a source situated in the water layer “ deformed”...
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Wide-field magnetometry using nitrogen-vacancy color centers with randomly oriented micro-diamonds
PublicationMagnetometry with nitrogen-vacancy (NV) color centers in diamond has gained significant interest among researchers in recent years. Absolute knowledge of the three-dimensional orientation of the magnetic field is necessary for many applications. Conventional magnetometry measurements are usually performed with NV ensembles in a bulk diamond with a thin NV layer or a scanning probe in the form of a diamond tip, which requires a...
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Tensile failure study of 3D printed PLA using DIC technique and FEM analysis
PublicationThe paper presents the experimental and numerical study of the failure behaviour of Fused Filament Fabricated (FFF) Polylactic Acid (PLA) samples subjected to tensile load. The examined samples are printed in flat orientation with 0◦, 45◦ and 90◦ raster angles. During the experiments the deformation of the specimens is continuously scanned with the 3D Aramis measuring system utilizing the digital imaging correlation technique,...
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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...
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Towards spectral sensitivity curve for two-photon vision mechanism
PublicationAbstract Purpose: The perceived brightness of different visible light sources can be compared with photometric units based on the standardized luminosity curves (300-780nm range). As reported previously (PNAS 111(50), pp. E5445-E5454 (2014)), near-infrared (NIR) radiation can cause isomerization of visual pigments by one- or two-photon absorption. The perceived color of the stimulus is red in the case of one-photon vision (1PV)...
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Effective dielectric constant of two phase dielectric systems
PublicationW tym artykule model brick-layer ścianie został rozszerzony na dwufazowe systemy perkolacyjne. Porównano wyniki obliczeń z danymi eksperymentalnymi. Stałe dielektryczne obu faz oraz próg perkolacji pozwala na wyznaczenie efektywnej stałej dielektrycznej systemu dwufazowego.
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Heat tint colours on stainless steel and welded joints
PublicationSurface layer condition of stainless steels and welded joints influences strongly their corrosion resistance. This problem seems to be underestimated. This current study explains the phenomenon of heat tint forming on welds, the methods of its removal, inspection procedures after heat tint removing and post weld finishing
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Badanie właściwości czujników wilgotności na bazie nanocząstek tlenku cynku
PublicationW celu pomiaru wilgotności szeroko stosowane są czujniki elektryczne. Warstwą czynną, zmieniającą swoje właściwości pod wpływem pary wodnej, stanowią najczęściej materiały ceramiczne lub polimerowe. Tlenek cynku jest jednym z materiałów ceramicznych będących dobrym kandydatem do zastosowania go jako warstwy czynną w czujnikach wilgotności. W tej pracy przedstawiono wyniki badań właściwości struktur czujnikowych z warstwą tlenku...
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Aktywny system RFID do lokalizacji i identyfikacji obiektów w wielomodalnej infrastrukturze bezpieczeństwa
PublicationPrzedstawiono prace koncepcyjne, badawcze oraz implementacyjne skoncentrowane na praktycznej realizacji systemu detekcji obiektów z wykorzystaniem kamer wizyjnych i identyfikacji radiowej. Zaproponowano rozbudowę wielomodalnego teleinformatycznego systemu bezpieczeństwa o warstwę identyfikacji radiowej obiektów. Omówiono założenia zaprojektowanego systemu oraz opracowaną warstwę sprzętową. Zaproponowano i przedyskutowano praktyczne...
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Przemiany strukturalne warstwy wierzchniej stopu Al-Si za pomocą nadtapiania laserowego w niskiej temperaturze
PublicationPrzedstawiono technologię laserowego nadtapiania w warunkach kriogenicznych stopu Al-Si przy mocy wiązki lasera 1500-6000 W. Wykazano wzrost odporności na korozję i zużycie ścierne po nadtapianiu. Uzasadniono obserwowane efekty utworzeniem struktury nanokrystalicznej i amorficznej.
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Optimalization of TiO2 nanotube geometry using fuzzy reasoning approach
PublicationThe geometry of TiO2 nanotube layer on titanium, obtained by electrochemical anodization, has been determined by using fuzzy reasoning approach. A proposed method showed the possibility of nanotube array architecture optimization by choosing an appropriate anodization condition. A fuzzy logic controller (FLC) was utilized using Matlab Software.
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On some accuracy limiting factors in wood sawing
PublicationPrzedstawiono szczegółową klasyfikację czynników determinujących dokładność przecinania drewna piłami. Uwzględniono w niej również pozorną utratę dokładności wynikającą z anatomicznej budowy drewna i metody pomiaru (wykorzystywanie lasera). Występujące błędy przecinania zobrazowano szeregiem przykładów z badań doświadczalnych.