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Wyniki wyszukiwania dla: fiber-optics sensors
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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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Screw displacement pile shaft deformations measured by vibrating wire and fiber optic systems during a static load test
PublikacjaThis paper describes a full scale static load test performed on a 400 mm diameter screw displacement pile equipped with four different strain measuring systems. Three types of vibrating wire strain gauges (VWSG) were used: global - retrievable, local attached to steel pipe and local concrete embedded. The fourth system was distributed fiber optic sensors based on Rayleigh back scattering (DFOS) - three in the pile cross section....
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On-line measurement of wood surface smoothness
PublikacjaThe latest progress in the field of optics and microelectronics resulted in development of new generation vision systems capable of scanning surface topography with very high sampling frequencies. The blue color of illuminating light as well as novel systems for controlling ultra-thin laser line thickness allows measurement of the porous surface of wood with a triangulation method. Three alternative sensors were tested here in...
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5G/6G optical fronthaul modeling: cost and energy consumption assessment
PublikacjaIn fifth generation (5G) and the future beyond 5G (6G) radio access networks (RANs), the cost of fronthaul deployment is a main challenge for mobile network operators. Depending on different constraints, there are various solutions to deploy an efficient fronthaul. Fiber-optic-based fronthaul offers long-term support with regard to a rapid increase in capacity demands. When fiber connections, either point-to-point (P2P) or point-to-multipoint...
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Nitrogen-Doped Diamond Film for Optical Investigation of Hemoglobin Concentration
PublikacjaIn this work we present the fabrication and characterization of a diamond film which can be utilized in the construction of optical sensors for the investigation of biological samples. We produced a nitrogen-doped diamond (NDD) film using a microwave plasma enhanced chemical vapor deposition (MWPECVD) system. The NDD film was investigated with the use of scanning electron microscopy (SEM), atomic force microscopy (AFM) and Raman...
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BP-EVD: Forward Block-Output Propagation for Efficient Video Denoising
PublikacjaDenoising videos in real-time is critical in many applications, including robotics and medicine, where varying light conditions, miniaturized sensors, and optics can substantially compromise image quality. This work proposes the first video denoising method based on a deep neural network that achieves state-of-the-art performance on dynamic scenes while running in real-time on VGA video resolution with no frame latency. The backbone...
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BPL-PLC Voice Communication System for the Oil and Mining Industry
PublikacjaApplication of a high-efficiency voice communication systems based on broadband over power line-power line communication (BPL-PLC) technology in medium voltage networks, including hazardous areas (like the oil and mining industry), as a redundant mean of wired communication (apart from traditional fiber optics and electrical wires) can be beneficial. Due to the possibility of utilizing existing electrical infrastructure, it can...
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Cost-Efficient Optical Fronthaul Architectures for 5G and Future 6G Networks
PublikacjaFifth-generation and Beyond (5GB) wireless networks have introduced new centralized architectures such as cloud radio access network (CRAN), which necessitate extremely high-capacity low latency Fronthaul (FH). CRAN has many advantageous features in terms of cost reduction, performance enhancement, ease of deployment, and centralization of network management. Nevertheless, designing and deploying a cost-efficient FH is still a...
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Functional fluorine-doped tin oxide coating for opto-electrochemical label-free biosensors
PublikacjaSensors operating in multiple domains, such as optical and electrochemical, offer properties making biosensing more effective than those working in a single domain. To combine such domains in one sensing device, materials offering a certain set of properties are required. Fluorine-doped tin oxide (FTO) thin film is discussed in this work as functional optically for guiding lossy modes and simultaneously electrochemically, i.e....
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Application of boron-doped diamond film and ZnO layer in the Fabry-Pérot interferometer
PublikacjaIn this article there have been presented the use of boron-doped diamond films for sensor applications. The low-finesse Fabry-Pérot interferometer working in the reflective mode has been implemented. Two kinds of reflective layers have been elaborated: boron-doped diamond thin films and zinc-oxide (ZnO) layer. Thin ZnO layers were deposited by Atomic Layer Deposition (ALD) on the face of a standard telecommunication single-mode...
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Tuning of the finesse coefficient of optoelectronic devices
PublikacjaOptoelectronic devices attracted considerable attention in many branches of science and technology, which can be attributed to their unique properties. Many of them use optical cavities which parameters can be adopted to specific requirements. This thesis investigates the introduction of diamond structures (nitrogen-doped diamond film, boron-doped diamond film, undoped diamond sheet) to optical cavities to tune their finesse coefficient....
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Sensitive Demonstration of the Twin-Core Couplers including Kerr Law Non-Linearity via Beta Derivative Evolution
PublikacjaTo obtain new solitary wave solutions for non-linear directional couplers using optical meta-materials, a new extended direct algebraic technique (EDAT) is used. This model investigates solitary wave propagation inside a fiber. As a result, twin couplers are the subject of this study. Kerr law is the sort of non-linearity addressed there. Because it offers solutions to problems with large tails or infinite fluctuations, the resulting...
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Low-cost multiband four-port phased array antenna for sub-6 GHz 5G applications with enhanced gain methodology in Radio-over-fiber systems using modulation instability
PublikacjaPhased array antenna (PAA) technology is essential for applications requiring high gain and wide bandwidth, such as sensors, medical, and 5G. Achieving such a design, however, is a challenging and intricate process that calls for precise calculations and a combination of findings to alter the phase and amplitude of each unit. Furthermore, coupling effects between these PAA structure elements can only be completed with the use of...
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Sensors and System for Vehicle Navigation
PublikacjaIn recent years, vehicle navigation, in particular autonomous navigation, has been at the center of several major developments, both in civilian and defense applications. New technologies, such as multisensory data fusion, big data processing, or deep learning, are changing the quality of areas of applications, improving the sensors and systems used. Recently, the influence of artificial intelligence on sensor data processing and...
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Imaging polarimeter with high-accuracy measuring principles in crystal optics
PublikacjaAn imaging polarimeter based on the principles of high-accuracy polarimetry well known in crystal optics is proposed. The application of scientific digital cameras for performance light measurements leads to precise data on polarizers quality, i.e., maps of extinction ratio and transmission axis. Processing of numerous images, acquired at various settings in the polarizer-sample-analyser system, allows to determine the two-dimensional...
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Efficient quadrature for fast oscillating integralof paraxial optics
PublikacjaThe study concerns the determination of quadrature for the integral solutionof the paraxial wave equation. The difficulty in computation of the integral isassociated with the rapid change of the integrand phase. The developed quadraturetakes into account the fast oscillating character of the integrand. The presentedmethod is an alternative to the commonly used methods based on the use of theFourier transform. The determination...
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Sensors and Sensor’s Fusion in Autonomous Vehicles
PublikacjaAutonomous vehicle navigation has been at the center of several major developments, both in civilian and defense applications. New technologies such as multisensory data fusion, big data processing, and deep learning are changing the quality of areas of applications, improving the sensors and systems used. New ideas such as 3D radar, 3D sonar, LiDAR, and others are based on autonomous vehicle revolutionary development. The Special...
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High-accuracy computation of hard X-ray focusing and imaging for refractive optics
PublikacjaA mathematical apparatus for solving problems of X-ray wave propagation through complex optical systems, when the lens thickness can change with jumps, is developed and presented. The developed method is based on the use of the superposition of oriented Gaussian beams, which satisfy the Helmholtz equation with high accuracy. The wave propagation in air and through kinoform and ordinary lenses is considered. Focusing and imaging...
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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...
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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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Identification of defected sensors in an array of amperometric gas sensors
PublikacjaPurpose Amperometric gas sensors are commonly used in air quality monitoring in long-term measurements. Baseline shift of sensor responses and power failure may occur over time, which is an obstacle for reliable operation of the entire system. The purpose of this study is to check the possibility of using PCA method to detect defected samples, identify faulty sensor and correct the responses of the sensor identified as faulty. Design/methodology/approach In...
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An adaptive-noise Augmented Kalman Filter approach for input-state estimation in structural dynamics
PublikacjaThe establishment of a Digital Twin of an operating engineered system can increase the potency of Structural Health Monitoring (SHM) tools, which are then bestowed with enhanced predictive capabilities. This is particularly relevant for wind energy infrastructures, where the definition of remaining useful life is a main driver for assessing the efficacy of these systems. In order to ensure a proper representation of the physical...
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Electrochemically directed biofunctionalization of a lossy-mode resonance optical fiber sensor
PublikacjaIn this work, we present a direct electrochemical biofunctionalization of an indium-tin-oxide-coated lossy-mode resonance optical fiber sensor. The functionalization using a biotin derivative was performed by cyclic voltammetry in a 10 mM biotin hydrazide solution. All stages of the experiment were simultaneously verified with optical and electrochemical techniques. Performed measurements indicate the presence of a poly-biotin...
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Application of Thin ZnO ALD Layers in Fiber-Optic Fabry-Pérot Sensing Interferometers
PublikacjaIn this paper we investigated the response of a fiber-optic Fabry-Pérot sensing interferometer with thin ZnO layers deposited on the end faces of the optical fibers forming the cavity. Standard telecommunication single-mode optical fiber (SMF-28) segments were used with the thin ZnO layers deposited by Atomic Layer Deposition (ALD). Measurements were performed with the interferometer illuminated by two broadband sources operating...
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A Review of Emotion Recognition Methods Based on Data Acquired via Smartphone Sensors
PublikacjaIn recent years, emotion recognition algorithms have achieved high efficiency, allowing the development of various affective and affect-aware applications. This advancement has taken place mainly in the environment of personal computers offering the appropriate hardware and sufficient power to process complex data from video, audio, and other channels. However, the increase in computing and communication capabilities of smartphones,...
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Flicker Noise in Resistive Gas Sensors—Measurement Setups and Applications for Enhanced Gas Sensing
PublikacjaWe discuss the implementation challenges of gas sensing systems based on low-frequency noise measurements on chemoresistive sensors. Resistance fluctuations in various gas sensing materials, in a frequency range typically up to a few kHz, can enhance gas sensing by considering its intensity and the slope of power spectral density. The issues of low-frequency noise measurements in resistive gas sensors, specifically in two-dimensional...
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Gas mixtures recognition using an array of amperometric gas sensors with drifting or faulty sensors
PublikacjaIn this study, the possibility of using selected methods for diagnostics of performance of matrix composed with six amperometric electrochemical gas sensors is investigated. Measurements of sensor responses in selected concentrations of single toxic gases or gas mixtures were performed and were repeated over time to show sensor drift. Additionally, the studies on the sensors’ drift were performed. The drift has been recognized...
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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...
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Highly sensitive microwave sensors based on open complementary square split-ring resonator for sensing liquid materials
PublikacjaThis paper presents high-sensitivity sensors based on open complementary square split-ring resonator and modified open complementary split-ring resonator operating at 4.5 GHz and 3.4 GHz, respectively. The sensors are designed for the detection of multiple liquid materials, including distilled water, methanol, and ethanol. The liquid under test is filled in a glass container loaded using a pipette. Compared to the conventional...
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Taguchi sensors under temperature modulation
PublikacjaSemiconductor gas sensors are widely used in gas- analyzing applications for various gas species determination due to their low cost and possibility to detect number of different gases. However, one of the main problems with such sensors is their lack of selectivity. To overcome this issue different ap- proaches can be used. One of them is the operation with sensor temperature modulation combined with dedicated data process- ing...
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The Effect of Flexible Pavement Mechanics on the Accuracy of Axle Load Sensors in Vehicle Weigh-in-Motion Systems
PublikacjaWeigh-in-Motion systems are tools to prevent road pavements from the adverse phenomena of vehicle overloading. However, the effectiveness of these systems can be significantly increased by improving weighing accuracy, which is now insufficient for direct enforcement of overloaded vehicles. Field tests show that the accuracy of Weigh-in-Motion axle load sensors installed in the flexible (asphalt) pavements depends on pavement temperature...
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Analytical fluctuation enhanced sensing by resistive gas sensors
PublikacjaResistance fluctuations across polarised resistive gas sensors were studied in detail to evaluate sensor working conditions for detecting methane and ammonia at various concentrations. The 1/f noise component typically dominates other noise sources up to a few kHz and can be utilised to improve gas selectivity when compared with measurements of the sensor DC resistance. The Arrhenius plot was created and the activation energy for...
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Portable Electronic Nose Based on Electrochemical Sensors for Food Quality Assessment
PublikacjaThe steady increase in global consumption puts a strain on agriculture and might lead to a decrease in food quality. Currently used techniques of food analysis are often labour-intensive and time-consuming and require extensive sample preparation. For that reason, there is a demand for novel methods that could be used for rapid food quality assessment. A technique based on the use of an array of chemical sensors for holistic analysis...
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Application of Ionic Liquids in Amperometric Gas Sensors
PublikacjaThis article presents an analysis of available literature data on metrological parameters of the amperometric gas sensors containing ionic liquids as an electrolyte. Four mechanism types of signal generation in amperometric sensors with ionic liquid are described. Moreover, this article describes the influence of selected physico-chemical properties of the ionic liquids on the metrological parameters of these sensors. Some metrological...
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Exhaled breath analysis by resistive gas sensors
PublikacjaBreath analysis has attracted human beings for centuries. It was one of the simplest methods to detect various diseases by using human smell sense only. Advances in technology enable to use more reliable and standardized methods, based on different gas sensing systems. Breath analysis requires the detection of volatile organic compounds (VOCs) of the concentrations below individual ppm (parts per million). Therefore, advanced detection...
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Fiber optic displacement sensor with signal analysis in spectral domain
PublikacjaIn this paper, a study of a low-coherence fiber optic displacement sensor is presented. The sensor consisted of a broadband source whose central wavelength was either at 1310 nm or 1550 nm, a sensing Fabry-Pérot interferometer operating in reflective mode and an optical spectrum analyzer acting as the detection setup. All these components were connected by a single-mode fiber coupler. Metrological parameters of the sensor were...
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Femtosecond Er-doped fiber laser source tunable from 872 to 1075 nm for two-photon vision studies in humans
PublikacjaWe report the development of a widely-tunable femtosecond fiber laser system and its application for two-photon vision studies. The source is based on an Er-doped fiber laser with spectral shift up to 2150 nm, followed by a second harmonic generation module to generate a frequency-doubled beam tunable from 872 to 1075 nm. The source delivers sub-230 fs pulses with nearly-constant duration over the entire tuning range, with output...
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Simple Measurement Method for Resistive Sensors Based on ADCs of Microcontrollers
PublikacjaA new, complete measurement method for resistance measurement of resistive sensors for systems based on microcontrollers equipped with analog-to-digital converters (ADCs) is proposed. The interface circuit consists of only four resistors, including a resistive sensor and a reference resistor, connected directly to the microcontroller pins. It is activated only during measurements, which significantly reduces power consumption....
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Inertial Sensors Applications in Underwater Measurements
PublikacjaOver the past decades microelectromechanical systems (MEMS) researchers have demonstrated a number of microsensors for almost every possible sensing modality, including attitudes. Current MEMS inertial measurement units (IMU) come in many shapes, sizes, and costs — depending on the application, and performance required. MEMS sensors have proved and demonstrated performance exceeding those of their macroscale counterpart sensors. In...
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UV-Light-Induced Fluctuation Enhanced Sensing by WO3-Based Gas Sensors
PublikacjaWO3-based gas sensors were investigated under UV-light irradiation and at different working temperatures with the object of achieving superior sensitivity and selectivity. Resistance fluctuations in the WO3 layer were studied together with dc resistance measurements. The data were taken in synthetic air, ethanol, nitrogen dioxide, and mixtures of these gases. We conclude that UV irradiation can easily be applied to enhance the...
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Selectivity of amperometric gas sensors in multicomponent gas mixtures
PublikacjaIn recent years smog and poor air quality became a growing environmental problem. There is a need to continuously monitor the quality of air. The lack of selectivity is one of the most important problems limiting the use of gas sensors for this purpose. In this study, a selectivity of the six amperometric gas sensors is being investigated. Calibration of sensors has been performed in order to find a correlation between concentration...
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Characterization of Highly Filled Glass Fiber/Carbon Fiber Polyurethane Composites with the Addition of Bio-Polyol Obtained through Biomass Liquefaction
PublikacjaThis work aims to investigate the process of obtaining highly filled glass and carbon fiber composites. Composites were manufactured using previously obtained cellulose derived polyol, polymeric methylene diphenyl diisocyanate (pMDI). As a catalyst, dibutyltin dilaurate 95% and Dabco® 33-LV were used. It was found that the addition of carbon and glass fibers into the polymer matrix causes an increase in the mechanical properties...
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An electronic nose based on the semiconducting and electrochemical gas sensors
PublikacjaThe practical application of human nose for fragrance recognition is severely limited by the fact that our sense of smell is subjective and gets tired easily. Consequently, there is a significant need for an instrument that can be a substitution of the human sense of smell. Development of an electronic nose devices is an active area of research starting from pioneering research of Dodd and Persuad in the mid-1980s. Such systems...
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GAS SENSORS WITH TEMPERATURE MODULATION – AN OVERVIEW
PublikacjaAlthough different methods of improving semiconductor gas sensor properties have been proposed, a technique involving temperature modulation seems to be the most promising. Semiconductor gas sensors working with modulated temperature can be more stable and are more selective comparing with sensor working at one temperature. In this paper, various approaches to temperature modulation are reviewed.
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Gas sampling system for matrix of semiconductor gas sensors
PublikacjaSemiconductor gas sensors are popular commercial sensors applied in numerous gas detection systems. They are reliable, small, rugged and inexpensive. However, there are a few problem limiting the wider use of such sensors. Semiconductor gas sensor usually exhibits a low selectivity, low repeatability, drift of response, strong temperature and moisture influence on sensor properties. Sample flow rate is one of the parameters that...
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High Dynamic Range Microwave Displacement and Rotation Sensors Based on the Phase of Transmission in Groove Gap Waveguide Technology
PublikacjaThis research is focused on the design and realization of displacement sensors in gap waveguide technology. It is shown that with a small but fundamental change in the structure of a conventional gap waveguide, a linear displacement can be sensed. To this end, a unique feature of gap waveguides, i.e. the fact that no electrical connection between the top and bottom parts of the gap waveguide is required, is used. It is further shown...
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Displacement Sensors Based on the Phase of the Reflection Coefficient of a Split Ring Resonator Loaded Transmission Line
Publikacja— In this paper, novel displacement sensors using a microstrip loaded with a pair of split ring resonators (SRRs) are proposed. It is shown that the phase of the reflection coefficient from the loading SRRs can be used for displacement sensing. The paper also proposes a differential version of the sensor that benefits from a higher sensitivity and reference zero, which is useful for alignment purposes. It is further shown that...
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Automatic Regularization by Quantization in Reducible Representations of CCR: Point-Form Quantum Optics with Classical Sources
PublikacjaElectromagnetic fields are quantized in a manifestly covariant way by means ofa class of reducible "center-of-mass N-representations" of the algebra of canonical commutationrelations (CCR). The four-potential Aa(x) transforms in these representations as aHermitian four-vector field in Minkowski four-position space (without change of gauge), butin momentum space it splits into spin-1 massless photons and two massless scalars. Whatwe...
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Essentials and merits of the method of analytical regularization in computational optics and photonics
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Analysis of activity of people using motion sensors
PublikacjaThe article presents the designed and implemented system for activity monitoring of people using passive motion sensors and methods for activity maps generation. In the paper he method is presented and results obtained for simulated data and for data from observations with the participation of people.