Wyszukiwarka
Wyniki wyszukiwania dla: OPTICAL MATERIALS
-
Optimizing FSO networks resilient to adverse weather conditions by means of enhanced uncertainty sets
PublikacjaThis work deals with dimensioning of wireless mesh networks (WMN) composed of FSO (free space optics) links. Although FSO links realize broadband transmission at low cost, their drawback is sensitivity to adverse weather conditions causing transmission degradation on multiple links. Hence, designing such FSO networks requires an optimization model to find the cheapest configuration of link capacities that will be able to carry...
-
Shrinking-shifting and amplifying-shifting device using transformation optics
PublikacjaBased on transformation optics (TO), this paper uses geometric divisions and linear coordinate transformations to design “shrinking-shifting—and reshaping”, and “amplifying-shifting—and reshaping” devices. The proposed devices can reshape the sizes and locations of the wrapped-objects inside the core-region. The shrinking-shifting device shrinks the larger object into a smaller one and shifts it to different location, whereas the...
-
Mathematical analysis of the lasing eigenvalue problem for the optical modes in a layered dielectric cavity with a quantum well and distributed Bragg reflectors
Publikacja -
An optimization model for robust FSO network dimensioning
Publikacja -
Optoelectronic and non-linear optical properties of Lu-doped AgGaGe3Se8 crystallites
Publikacja -
Information-driven network resilience: Research challenges and perspectives
PublikacjaInternet designed over 40 years ago was originally focused on host-to-host message delivery in a best-effort manner. However, introduction of new applications over the years have brought about new requirements related with throughput, scalability, mobility, security, connectivity, and availability among others. Additionally, convergence of telecommunications, media, and information technology was responsible for transformation...
-
Opto-Electrochemical Sensing Device Based on Long-Period Grating Coated with Boron-Doped Diamond Thin Film
PublikacjaThe fabrication process of thin boron-doped nanocrystalline diamond (B-NCD) microelectrodes on fused silica single mode optical fiber cladding has been investigated. The B-NCD films were deposited on the fibers using Microwave Plasma Assisted Chemical Vapor Deposition (MW PA CVD) at glass substrate temperature of 475 ºC. We have obtained homogenous, continuous and polycrystalline surface morphology with high sp3 content in B-NCD...
-
Low to intermediate energy elastic electron scattering from dichloromethane (CH2Cl2)
PublikacjaWe report a theoretical-experimental investigation of electron scattering by dichloromethane (CH2Cl2) in the low- and intermediate energy ranges. Experimental elastic differential cross sections (DCS), in the incident electron energy range of 0.5-800 eV and scattering angle range of 10°–130°, were measured using a crossed beam relative flow technique. Integral and momentum- transfer cross sections were determined from the experimental...
-
Optical-Fiber Microsphere-Based Temperature Sensors with ZnO ALD Coating—Comparative Study
PublikacjaThis study presents the microsphere-based fiber-optic sensor with the ZnO Atomic Layer Deposition coating thickness of 100 nm and 200 nm for temperature measurements. Metrological properties of the sensor were investigated over the temperature range from 100 °C to 300 °C, with a 10 °C step. The interferometric signal was used to monitor the integrity of the microsphere and its attachment to the connecting fiber. For the sensor...
-
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...
-
PROGRAMMABLE YANG - BASED INTERFACE IN CONTROL OF OPTICAL TRANSPORT NETWORK
PublikacjaSince over a decade we observe intensive effort of research institutions and industrial consortia on extending flexibility and automation of the transport network control also known under the term network programmability. Key aspect of each programming interface is ability to evolve but also sensitivity to future modifications. As indicated in the past work in the specific context of optical transport networks an important criterion...
-
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...
-
Salinity enhances high optically active L-lactate production from co-fermentation of food waste and waste activated sludge: Unveiling the response of microbial community shift and functional profiling
PublikacjaLactic acid (LA), a versatile platform molecule, can be fermented from organic wastes, such as food waste and waste activated sludge. In this study, an efficient approach using salt, a component of food waste as an additive, was proposed to increase LA production. The LA productivity was increased at 10 g NaCl/L and optical pure L-lactate was obtained at 30 g NaCl/L. The enhancement of LA was in accordance with the increased solubilization...
-
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...
-
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...
-
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...
-
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...
-
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...
-
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.
-
An Optical Low-Coherence System for 2-Dimensional Visualization of Thin Polymer Layers
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.
-
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.
-
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.
-
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...
-
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...
-
Optical flow method for measuring deformation of soil specimen subjected to torsional shearing
PublikacjaIn this study optical flow method was used for soil small deformation measurement in laboratory tests. The main objective was to observe how the deformation distributes along the whole height of cylindrical soil specimen subjected to torsional shearing (TS test). The experiments were conducted on dry non-cohesive soil specimens under two values of isotropic pressure. Specimens were loaded with low-amplitude cyclic torque to analyze...
-
Brownian Motion in Optical Tweezers, a Comparison between MD Simulations and Experimental Data in the Ballistic Regime
PublikacjaThe four most popular water models in molecular dynamics were studied in large-scale simulations of Brownian motion of colloidal particles in optical tweezers and then compared with experimental measurements in the same time scale. We present the most direct comparison of colloidal polystyrene particle diffusion in molecular dynamics simulations and experimental data on the same time scales in the ballistic regime. The four most...
-
Non invasive optical cellular imaging in humans.
PublikacjaOne of the most appealing and still unsolved problems in biological and medical imaging is the possibility of noninvasive visualization of tissue in vivo with an accuracy of microscopic examination. A major difficulty to solve in biomedical imaging is a degradation of image quality caused by the presence of optical inhomogeneity of tissue. Is there any chance to develop a microscopic method that allows non-invasive observation...
-
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...
-
Efficient Complex Root Finding Algorithm for Microwave and Optical Propagation Problems
PublikacjaArticle relates to the use of innovative root finding algorithm (on a complex plane) to study propagation properties of microwave and optical waveguides. Problems of this type occur not only in the analysis of lossy structures, but also in the study of complex and leaky modes (radiation phenomena). The proposed algorithm is simple to implement and can be applied for functions with singularities and branch cuts in the complex plane...
-
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...
-
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,...
-
The passive operating mode of the linear optical gesture sensor
PublikacjaThe study evaluates the influence of natural light conditions on the effectiveness of the linear optical gesture sensor, working in the presence of ambient light only (passive mode). The orientations of the device in reference to the light source were modified in order to verify the sensitivity of the sensor. A criterion for the differentiation between two states - "possible gesture" and "no gesture" - was proposed. Additionally,...
-
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...
-
Estimation of the amplitude of the signal for the active optical gesture sensor with sparse detectors
PublikacjaIn this paper we deal with the problem of precise gesture recognition for the active optical proximity sensor with sparse 8 photodiodes. We particularly focus on developing the method of estimating the real, usually not observable, maximum signal value representing maximum intensity of light reflected from an obstacle present in the front of the sensor. Different configurations of the fingers were used as an obstacle. The Monte Carlo...
-
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.
-
Microcrystalline diamond film evaluation by spectroscopic optical coherence tomography
PublikacjaThis study has focused on the microcrystalline diamond film (MCD) thickness evaluation. For this purpose, optical coherence tomography (OCT) enhanced by spectroscopic analysis has been used as a method of choice. The average thickness of the tested layer was about 1.5 µm, which is below the standard 2-point OCT resolution. In this case, the usefulness of the spectroscopic analysis was confirmed for the evaluation of the thickness...
-
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...
-
Computer support of analysis optical spectra measurements
PublikacjaVerification of measurement errors has a big impact on assessment of accuracy of conducted measurements and obtained results. In many cases computer simulation results are compared with measurement results in order to evaluate measurement errors. The purpose of our research was to check the accuracy of measurements made with Fabry-Perot interferometer working in the transmission mode. In measurement setup, a 1310 nm superluminescent...
-
Nondestructive Optical Sensing of Flavonols and Chlorophyll in White Head Cabbage ( Brassica oleracea L. var. capitata subvar. alba ) Grown under Different Nitrogen Regimens
PublikacjaA multiparametric optical sensor was used to nondestructively estimate phytochemical compounds in white cabbage leaves directly in the field. An experimental site of 1980 white cabbages (Brassica oleracea L. var. capitata subvar. alba), under different nitrogen (N) treatments, was mapped by measuring leaf transmittance and chlorophyll fluorescence screening in one leaf/cabbage head. The provided indices of flavonols (FLAV) and...
-
The potential of imogolite nanotubes as (co-)photocatalysts: a linear-scaling density functional theory study
PublikacjaWe report a linear-scaling density functional theory (DFT) study of the structure, wall-polarization absolute band-alignment and optical absorption of several, recently synthesized, open-ended imogolite (Imo) nanotubes (NTs), namely single-walled (SW) aluminosilicate (AlSi), SW aluminogermanate (AlGe), SW methylated aluminosilicate (AlSi-Me), and double-walled (DW) AlGe NTs. Simulations with three different semi-local and dispersion-corrected...
-
Advanced Monte Carlo simulator of the polarization-sensitive optical coherence tomography systems
PublikacjaSimulations of the optical coherence tomography (OCT) systems using the Monte Carlo method is a widely explored research area. However, there are several difficulties that need to be overcome in order to properly model the OCT imaging with the Monte Carlo algorithm. First of all, the temporal and the spatial coherence of the scattered light need to be considered, since OCT is based on the interference phenomenon. For the same reason,...
-
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....
-
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...
-
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...
-
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...
-
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...
-
Detection of immunological agent by optical fiber sensor: preliminary study
PublikacjaThe objective of this study is the application of optical methods for detection of immunological agent concentration. As the agent we used the Cyclaid, produced by Apotex Inc. In this article we investigated different Cyclaid concentrations in water. We used a Fabry-Pérot interferometer working in a reflective mode, the measurements were performed with source with central wavelength λ = 1550 nm. The preliminary investigation have...
-
Burst loss probability for the combination of extended offset time based service differentiation scheme and PPS in optical burst switching network
PublikacjaIn the paper analytical model for calculating burst loss probabilities for the combination of two service differentiation schemes for OBS network namely: extended offset time based scheme and PPS (Preemption Priority Schemes) is revised. Moreover authors introduce analytical model for calculating burst loss probabilities for an optical path when OBS network employs both service differentiation schemes and JET signaling. The comparison...
-
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...
-
Optical fiber aptasensor for label-free bacteria detection in small volumes
PublikacjaHighly sensitive devices for fast bacteria detection are sought to be developed with the task of quantifying the worldwide problem of pathogenic bacteria and thus helping to take control over spreading bacterial infections. This work concerns a sensing solution based on microcavity in-line Mach-Zehnder interferometer (μIMZI) induced in an optical fiber. Such a device exhibits ultrahigh sensitivity to refractive index changes...