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Wyniki wyszukiwania dla: OPTICAL ACTIVITY
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Recent and Emerging Applications of Graphene-based metamaterials in Electromagnetics
PublikacjaSurface Plasmon Polaritons (SPPs) operating in mid-infrared up to terahertz (THz) frequencies have been traditionally manufactured on expensive metals such as gold, silver, etc. However, such metals have poor surface confinement that limits the optical applications of SPPs. The invention of graphene is a breakthrough in plasmon-based devices in terms of design, fabrication and applications, thanks to its plasmonic wave distribution,...
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Application of two-dimensional intensity maps in high-accuracy polarimetry
PublikacjaWe propose the analysis of 2D intensity contour maps which is based on the optical transmission function for the polarizer-specimen-analyzer system. A small modification of the high-accuracy universal polarimeter (HAUP) technique was used to measure the intensity maps (HAUP maps) and determine the phase retardation, linear dichroism (LD) parameters, and multiple light reflection contribution in uniaxial crystals. We have performed...
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Luminance Distribution Measurements in CAVE-Type Virtual Reality Systems
PublikacjaIn this article, the immerse 3D visualization lab just opened at the Gdańsk University of Technology is presented. The effect of user “immersion,” it such virtual reality systems, is largely dependent on the optical properties of projected images. Luminance distribution of screens was measured and the luminance uniformity was determined and discussed.
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Spectroscopic and wireless sensor of hematocrit level
PublikacjaAn optical method for hematocrit measurement has been presented. the sensor, designed and developed by authors, consists of spectroscopic set-up controlled by a microcontroller. measurement results are sent via wireless module. experiment has confirmed the ability of the sensor to determine the hematocrit with appropriate measurementaccuracy.
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Detection of gaseous compounds with different techniques
PublikacjaSensing technology has been developed for detection of gases in some environmental, industrial, medical, and scientific applications. The main tasks of these works is to enhance performance of gas sensors taking into account their different applicability and scenarios of operation. This paper presents the descriptions, comparison and recent progress in some existing gas sensing technologies. Detailed introduction to optical sensing...
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Detection of Face Position and Orientation Using Depth Data
PublikacjaIn this paper an original approach is presented for real-time detection of user's face position and orientation based only on depth channel from a Microsoft Kinect sensor which can be used in facial analysis on scenes with poor lighting conditions where traditional algorithms based on optical channel may have failed. Thus the proposed approach can support, or even replace, algorithms based on optical channel or based on skeleton...
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Efficiency limit of excitonic photovoltaic cells under phosphor-based white LED illumination
PublikacjaThe limit of energy conversion of excitonic photovoltaic cells working under white light illumination generated by phosphor-based LED is analysed using the modified Giebink approach. Particularly, the impact of the optical energy gap and energy loss associated with the excitons dissociation at the heterojunction interface on power conversion efficiency of the device are discussed. From the results of our study it follows that the...
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Fractal dimension for bending–torsion fatigue fracture characterisation
PublikacjaFracture surfaces after biaxial fatigue tests were compared using fractal dimension for three types of metallic materials in smooth and notched specimens made of S355J2 and 10HNAP steels and 2017-T4 aluminium alloy, considering both proportional and nonproportional cyclic loading. High-resolution optical 3D measurement studies were performed on the entire fracture surface. A direct correlation between fractal dimension and fatigue...
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Absorption spectroscopy setup for determination of whole human blood and blood–derived materials spectral characteristics
PublikacjaA dedicated absorption spectroscopy system was set up using tungsten-halogen broadband source, optical fibers, sample holder, and a commercial spectrometer with CCD array. Analysis of noise present in the setup was carried out. Data processing was applied to the absorption spectra to reduce spectral noise, and improve the quality of the spectra and to remove the baseline level. The absorption spectra were measured for whole blood...
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Optoelectronic device for hematocrit measurements
PublikacjaAn optoelectronic system for measurements of hematocrit level (HCT) in the whole human blood is presented. Proposed system integrates a dedicated optoelectronic sensor, a microcontroller and a small LCD display in a low cost, battery-powered, handheld device. Chosen method for determining blood hematocrit level is based on optical properties of whole blood in visible and NIR wavelength range. Measurements with the use of proposed...
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Non-invasive investigation of a submerged medieval harbour, a case study from Puck Lagoon
PublikacjaThis study presents an innovative approach to underwater archaeological prospection using non-invasive methods of seabed exploration. The research focuses on the Puck medieval harbour, a cultural heritage site, and utilises acoustic and optical underwater remote-sensing technology. The primary objectives include optimising the use of Airborne Laser Bathymetry in underwater archaeology, enhancing the filtration process for mapping...
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Topography measurement methods evaluation for entire bending-fatigued fracture surfaces of specimens obtained by explosive welding
PublikacjaIn this paper, the methods of compensation of differences in the results of entire bending-fatigued fracture surface topographies were presented. The roughness evaluation was performed with a focus variation microscope and confocal surface topography measurement techniques. The differences in the ISO 25178 roughness parameters were investigated and procedures for their compensation were studied. It was found that various types...
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Review of the Usefulness of Various Rotational Seismometers with Laboratory Results of Fibre-Optic Ones Tested for Engineering Applications
PublikacjaStarting with descriptions of rotational seismology, areas of interest and historical field measurements, the fundamental requirements for rotational seismometers for seismological and engineering application are formulated. On the above basis, a review of all existing rotational seismometers is presented with a description of the principles of their operation as well as possibilities to fulfill formulated requirements. This review...
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A new method of presosns identification based on comparative analysis of 3D face models
PublikacjaThe article presents the use of modern close range photogrammetry for possessing highly accurate 3D models of the human face (including the ears). Modern methods used to obtain precise data describing the construction of a human face, and even the whole human body, should allow to get finished measurement material in a very short time. Those features belong to the optical scanning technology. Comparative analysis of models of the...
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Fiber-optic sensors based on microspheres with nanocoatings (Zastosowanie mikrosfer optycznych z cienkowarstwowymi pokryciami w czujnikach światłowodowych)
PublikacjaTemperature is one of the most important physical quantities. Temperature measurements are used in every field of life, especially electronics, electrical engineering, energy-related fields, including energy source and storage devices. The goal of this dissertation is to design and optimize the microsphere-based fiber-optic sensors construction for measurement of the sensor surrounding medium temperature, including selection of...
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Gas Composition Influence on the Properties of Boron-Doped Diamond Films Deposited on the Fused Silica
PublikacjaThe main subject of this study are molecular structures and optical properties of boron-doped diamond films with [B]/[C] ppm ratio between 1000 and 10 000, fabricated in two molar ratios of CH 4 -H 2 mixture (1 % and 4 %). Boron-doped diamond (BDD) film on the fused silica was presented as a conductive coating for optical and electronic purposes. The scanning electron microscopy images showed homogenous and polycrystalline surface...
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Influence of reactive oxygen species during deposition of iron oxide films by high power impulse magnetron sputtering.
PublikacjaIron oxide films were deposited using high power impulse magnetron sputtering (HiPIMS) of an iron cathode in an argon/oxygen gas mixture at different gas pressures (0.5~Pa, 1.5~Pa, and 5.0~Pa). The HiPIMS system was operated at a repetition frequency $f = 100$~Hz with a duty cycle of 1~\%. A main goal is a comparison of film growth during conventional and electron cyclotron wave resonance-assisted HiPIMS. The deposition plasma...
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In-situ monitoring of electropolymerization processes at boron-doped diamond electrodes by Mach-Zehnder interferometer
PublikacjaIn this work, the Mach-Zehnder interferometer was designed to monitor the electrochemical processes conducted at boron-doped diamond electrode surface. The diamond electrodes were synthesized via Microwave Plasma-Assisted Chemical Vapor Deposition on optical grade quartz glass. The achieved transmittance in working are of diamond electrodes reached 55 %. A cage system-based Mach-Zehnder interferometer was used which allowed the...
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Zastosowanie optycznej tomografii niskokoherentnej do 2-wymiarowego obrazowania cienkich warstw polimerów
PublikacjaW artykule omówiono zasadę działania i przedstawiono podstawowe właściwości systemu OCT (Optical Coherence Tomography). Na przykładzie folii polietylenowej przedyskutowano możliwości wykorzystania systemu do badanie wewnętrznej struktury warstwowej obiektów niebiologicznych. Przedstawiono i omówiono wyniki przeprowadzonych badań nad warstwowymi materiałami przeźroczystymi.
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Guido: a musical score recognition system
PublikacjaThis paper presents an optical music recognition system Guido that can automatically recognize the main musical symbols of music scores that were scanned or taken by a digital camera. The application is based on object model of musical notation and uses linguistic approach for symbol interpretation and error correction. The system offers musical editor with a partially automatic error correction.
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Efficient method for octahedral NH2-MIL-125 (Ti) synthesis: Fast and mild conditions
PublikacjaA new hot injection method for preparing octahedral NH2-MIL-125 (Ti) was developed. This method is six times faster and conducted under milder conditions, i.e., at 120°C in a flask, and exhibits higher crystal formation efficiency than the commonly used solvothermal method while maintaining comparable structural, optical, and photocatalytic properties.
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The finite difference methods of computation of X-rays propagation through a system of many lenses
PublikacjaThe propagation of X-ray waves through an optical system consisting of many beryllium X-ray refrac- tive lenses is considered. In order to calculate the propagation of electromagnetic in the optical sys- tem, two differential equations are considered. First equation for an electric field of a monochromatic wave and the second equation derived for complex phase of the same electric The propagation of X-ray waves through an optical system...
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Quantum and carbon dots conjugated molecularly imprinted polymers as advanced nanomaterials for selective recognition of analytes in environmental, food and biomedical applications
PublikacjaSamples with complex matrix analyzed during explanation of pathogenesis of various diseases and food or environmental monitoring request advanced analytical and instrumental devices. Among the materials used for described purposes, quantum (QDs) or carbon dots (CDs) layered by molecularly imprinted polymer (MIP) shells have gained widespread attention. Unique optical and physicochemical properties of QDs/CDs together with high...
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High-performance graphene-based biosensor using a metasurface of asymmetric silicon disks
PublikacjaIn recent years, optical biosensors widely applicable for medical applications, have received much attention. In this paper, we propose a high-performance polarization-insensitive optical biosensor based on a graphene-dielectric metasurface. The metasurface consists of an asymmetric dielectric disk array that supports a high Q-factor Fano resonance. The provided sharp Fano resonance results in an enhanced light-matter interaction...
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Thermodynamics of solid phases containing rare earth oxides
PublikacjaRare earth elements (RE) are incorporated into a large variety of complex oxide phases to provide tailored mechanical, electrical, optical, and magnetic properties. Thermodynamics control phase stability, materials compatibility in use, corrosion, and transformation. This review presents, in one compilation, the thermodynamic properties of a large number of such materials and discusses systematic trends in energetics and the factors...
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Spectroscopic wireless sensor of hematocrit level
PublikacjaAn optical method for hematocrit measurement is presented. The sensor, designed and developed by authors, consists of a spectroscopic set-up and a microcontroller. The work of the sensor is based on measurement of intensity of two selected spectral bands. Tests confirmed the ability of the sensor to determine the hematocrit level with appropriate measurement accuracy. Measurement results can be transmitted via wireless module to...
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Response of a New Low-Coherence Fabry-Perot Sensor to Hematocrit Levels in Human Blood
PublikacjaIn this paper, a low-coherence Fabry-Perot sensor with a spectrally measured signal processing response to the refractive index of liquids is presented. Optical fiber sensors are potentially capable of continuous measuring hematocrit levels in blood. Low-coherence Fabry-Perot interferometric sensors offer a robust solution, where information about the measurand is encoded in the full spectrum of light reflected from the sensing...
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Predictions of cervical cancer identification by photonic method combined with machine learning
PublikacjaCervical cancer is one of the most commonly appearing cancers, which early diagnosis is of greatest importance. Unfortunately, many diagnoses are based on subjective opinions of doctors—to date, there is no general measurement method with a calibrated standard. The problem can be solved with the measurement system being a fusion of an optoelectronic sensor and machine learning algorithm to provide reliable assistance for doctors...
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Thermomagnetic behavior of a semiconductor material heated by pulsed excitation based on the fourth-order MGT photothermal model
PublikacjaThis article proposes a photothermal model to reveal the thermo-magneto-mechanical properties of semiconductor materials, including coupled diffusion equations for thermal conductivity, elasticity, and excess carrier density. The proposed model is developed to account for the optical heating that occurs through the semiconductor medium. The Moore–Gibson–Thompson (MGT) equation of the fourth-order serves as the theoretical framework...
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Natural carbon-based quantum dots and their applications in drug delivery: A review
PublikacjaNatural carbon based quantum dots (NCDs) are an emerging class of nanomaterials in the carbon family. NCDs have gained immense acclamation among researchers because of their abundance, eco-friendly nature, aqueous solubility, the diverse functionality and biocompatibility when compared to other conventional carbon quantum dots (CDs).The presence of different functional groups on the surface of NCDs such as thiol, carboxyl, hydroxyl,...
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Eine Eeue Technik zur Präzisen Rissfortschrittsmessung im DCB oder im Keilversuch = A novel technique for precise crack length measurement in the DCB or wedge test
PublikacjaDiverse methods have been tried to study crack length, most basic relying on direct, or microscopic, observation of the crack tip position. Optical correlation, both lasermoiré and speckle interferometry, a single strain gauge and displacement sensorshave also been employed. Crack length measurement is, however, delicate. We present a novel method making use of strain gauges attached to one of the adherends.
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Sensors for Rapid Detection of Environmental Toxicity in Blood of Poisoned People
PublikacjaRecently, the diagnosis and treatment of poisoned person can be done only in specialized centers. Furthermore, currently used clinical methods of intoxication diagnosis are not sufficient for early detection. Conventional laboratory tests based on urine and blood require professional, high skilled staff, high cost equipment as well as they are arduous and lasting analytical procedures. There is a need to elaborate relatively cheap...
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Inkjet Printing of Lanthanide–Organic Frameworks for Anti-Counterfeiting Applications
PublikacjaPhotoluminescent lanthanide−organic frameworks (Ln-MOFs) were printed onto plastic and paper foils with a conventional inkjet printer. Ln-MOF inks were used to reproduce color images that can only be observed under UV light irradiation. This approach opens a new window for exploring Ln-MOF materials in technological applications, such as optical devices (e.g., lab-on-a-chip), as proof of authenticity for official documents.
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Investigation of the Few‐Layer Black Phosphorus Degradation by the Photonic Measurements
PublikacjaFew-layer black phosphorus (FLBP) is a 2D material that gains worldwide interest for its possible applications, mainly in electronics and optoelec-tronics. However, as FLBP is prone to a degradation process under envi-ronmental conditions, there is a need for a monitoring method allowing investigation of its surface quality. Among many techniques, optoelectronic ones have unique advantages of fast response, non-contact, and non-invasive...
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Preparation and Characterization of Microsphere ZnO ALD Coating Dedicated for the Fiber-Optic Refractive Index Sensor
PublikacjaWe report the fabrication of a novel fiber-optic sensor device, based on the use of a microsphere conformally coated with a thin layer of zinc oxide (ZnO) by atomic layer deposition (ALD), and its use as a refractive index sensor. The microsphere was prepared on the tip of a single-mode optical fiber, on which a conformal ZnO thin film of 200 nm was deposited using an ALD process based on diethyl zinc (DEZ) and water at 100 °C....
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Using MusicXML to evaluate accuracy of OMR Systems
PublikacjaIn this paper a methodology for automatic accuracy evaluation in optical music recognition (OMR) applications is proposed. Presented approach assumes using ground truth images together with digital music scores describing their content. The automatic evaluation algorithm measures differences between the tested score and the reference one, both stored in MusicXML format. Some preliminary test results of this approach are presented...
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Application of the laser diode with central wavelength 975 nm for the therapy of neurofibroma and hemangiomas
PublikacjaThis paper presents newly developed dermatological laser (with central wavelength 975 nm) for application in therapies requiring deep penetration of tissue, e.g. cutaneous (dermal) neurofibroma (Recklinghausen disease) and hemangiomas. This laser can work either in pulse or continues wave mode. Laser radiation is transmitted toward the application region by optical fiber with a diameter of 0.6 mm. The compact design of the laser...
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DFT studies of the refractive index of boron-doped diamond
PublikacjaThe density functional theory is one of the optimal solutions in calculation of optical properties of materials on the quantum scale. In this paper, we have investigated the refractive index of a boron-doped diamond structure with the usage of Atomistic Toolkit software from Synopsys. During this study, various methods and pseudopotentials were checked to obtain an optimal performanceaccuracy method for calculation of such materials....
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Measurement of the Temporal and Spatial Temperature Distribution on the Surface of PVCP Tissue Phantom Illuminated by Laser Dataset
PublikacjaThe dataset entitled Measurement of the temporal and spatial temperature distribution on the surface of PVCP tissue phantom illuminated by laser was obtained with a laboratory set-up for characterisation of the thermal properties of optical tissue phantoms during laser irradiation. The dataset contains a single image file representing the spatial temperature distribution on the surface of a PVCP tissue phantom. This thermal image...
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Effect of temperature change on refractive index of an egg white and yolk: a preliminary study
PublikacjaIn this article, the refractive index of an egg white and yolk depending on temperature in range 30 - 47 °C over 1550 nm was determined. The measurement head was constructed as fiber optic Fabry-Perot interferometer with interference between polished fiber end-face and aluminum weighing dish. The measurement setup has been made of an optical spectrum analyzer, a superluminescent diode with a central wevelength of 1550 nm, 2:1 fiber...
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Coherent-wave Monte Carlo method for simulating light propagation in tissue
PublikacjaSimulating propagation and scattering of coherent light in turbid media, such as biological tissues, is a complex problem. Numerical methods for solving Helmholtz or wave equation (e.g. finite-difference or finite-element methods) require large amount of computer memory and long computation time. This makes them impractical for simulating laser beam propagation into deep layers of tissue. Other group of methods, based on radiative...
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Low-Level Aerial Photogrammetry as a Source of Supplementary Data for ALS Measurements
PublikacjaThe development of laser scanning technology ALS allows to make high-resolution measurements for large areas result-ing in significant reduction of costs. The main stakeholders at heights data received from the airborne laser scanning is mainly state administration. The state institutions appear among projects such as ISOK. Each point is classified in ac-cordance with the standard LAS 1.2, our research focuses on the class 6 -...
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Magnetically sensitive fiber probe with nitrogen-vacancy center nanodiamonds integrated in a suspended core
PublikacjaEfficient collection of photoluminescence arising from spin dynamics of nitrogen vacancy (NV) centers in diamond is important for practical applications involving precise magnetic field or temperature mapping. These goals may be realized by the integration of nanodiamond particles with optical fibers and volumetric doping of the particles alongside the fiber core. That approach combines the advantages of robust axial fixation of...
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A navigation device utilizing body communication channel for mobile wearable systems
PublikacjaA novel touch sensor utilizing a body communication technology is presented in the paper. The proposed device accepts orders (gestures) only from a person wearing it. Moreover, when comparing it to a similar, however an optical one, it appears as a less power consumable. Preliminary results of its properties examination are presented and discussed. Additionally, the developed sensor allows to measure a human body the electrical...
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Physical properties of homogeneous TiO2 films prepared by high power impulse magnetron sputtering as a function of crystallographic phase and nanostructure
PublikacjaOptical, photo-electrochemical, crystallographic and morphological properties of TiO2 thin films prepared by high power impulse magnetron sputtering at low substrate temperatures (<65 ◦C) without post-deposition thermal annealing are studied. The film composition-anatase, rutile or amorphous TiO2-is adjusted by the pressure (p ∼ 0.75-15 Pa) in the deposition chamber. The different crystallographic phases were determined with grazing...
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Niobate in silicate and phosphate glasses: Effect of glass basicity on crucible dissolution
PublikacjaUsing niobium crucibles for melting phosphate and silicate glasses of various modifier oxide contents, and therefore varying optical basicity (Λ), was found to result in varying dissolution rates of niobate during melting. Because of their high electronic polarizability, even small concentrations of niobates are detectable in the Raman spectra of glasses. Even less than 1 mol% Nb2O5 can be identified, as independently confirmed...
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Reduction of parasitic pitch variations in archival musical recordings
PublikacjaA new method for reducing parasitic pitch variations in archival audio recordings is presented. The method is intended for analyzing movie soundtracks recorded in optical films. It utilizes image processing for calculating and reducing effects of tape shrinkage being one of the main reasons for parasitic pitch variations in audio accompanying moving images. As long as the film tape characteristics are known the new method can be...
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Optoelektroniczny system przestrzennego monitoringu wzbudzenia plazmy w procesach syntezy optycznych warstw diamentopodobnych
PublikacjaPrzedmiotem pracy jest optoelektroniczny system do badania wzbudzenia plazmy mikrofalowej w procesie syntezy warstw DLC (ang. Diamond Like-Carbon). W komunikacie zaprezentowano budowę systemu do przestrzennego monitoringu stanu wzbudzenia plazmy podczas procesu CVD. System SR-OES (ang. Spatially Resolved Optical Emission Spectroscopy) umożliwia określanie rozkładu wzbudzenia cząstek w przestrzeni komory i na tej podstawie wybrania...
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High Resolution Sea Ice Floe Size and Shape Data from Knox Coast, East Antarctica
PublikacjaThis dataset contains floe size distribution data from a very high resolution (pixel size: 0.3 m) optical satellite image of sea ice, acquired on 16 Feb. 2019 off the Knox Coast (East Antarctica). The image shows relatively small ice floes produced by wave-induced breakup of landfast ice between Mill Island and Bowman Island. The ice floes are characterised by a narrow size distribution and angular, polygonal shapes, typical...
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The new version of contact-less method for localisation of catenary contact wire – theoretical assumption
PublikacjaThis article presents the theoretical basic of a new version of contact-less method for localising the catenary contact wires, using the advanced video techniques and image analysis. So far, contact line diagnostic systems exploited nowadays uses the contact measuring methods with special design current collector. This solutions make it impossible to measure the contact line geometry in a static way. The proposed measurement method...