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Wyniki wyszukiwania dla: light transmission measurement
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Research and Analysis of High-Speed Data Transmission Radio Link Designed for Maritime Environment
PublikacjaIn these article, the realization of digital radio link for high-speed data transmission was presented. Its concept and practical realization, using USRP devices from National Instruments, were described. Developed software for generation and reception of digital signals in baseband, including description of modulation types, and time and frequency synchronization mechanisms, was presented. Moreover, an operation of designed radio...
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Performance of data transmission in UMTS with turbo code about decreased number of states
PublikacjaIn the paper a structure of turbo encoder and decoder about decreased number of states has been described. The simulation results of transmission performance based on turbo coding without the reduction of the number of iterations for the uplink and downlink of WCDMA/FDD interface have been presented. The SOVA algorithm for turbo decoding has been used. The investigations have been carried out for Outdoor to Indoor & Pedestrian...
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Multi-functional sensor based on photonic crystal fiber using plasmonic material and magnetic fluid
PublikacjaA unique highly sensitive photonic crystal fiber is investigated based on plasmonic material and magnetic fluid (MF) for the simultaneous measurement of temperature and magnetic field sensor. The designed sensor is explored by tracing the different parameters such as birefringence, coupling length, power spectrum, and the peak wavelength of the transmission intensity. The magnetic field and temperature computation are attained...
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Analysis of Video Transmission Capabilities in a Simulated OFDM-Based Supplementary BPL-PLC System
PublikacjaThe design and maintenance of a reliable communication system, especially in harsh working conditions for the oil and mining industry, brings many challenges. With the use of a video transmission system, one can monitor the crew and their working environment. Broadband over power line–power line communication (BPL-PLC) seems an ideal medium for such a service, since it enables the use of the existing wired infrastructure for supplementary...
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Quaternion encryption methods for multimedia transmission, a survey of existing approaches
PublikacjaIn this paper we review quaternion encryption methods for multimedia transmission. We explain their weak and strong properties as well as suggest possible modifications. Our main focus is an algorithm QFC presented in paper by Dzwonkowski et al. (2015). All encryption methods, presented in this paper, use special properties of quaternions to perform rotations of data sequences in 3D space. Each method uses a common key generation...
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Approximate models and parameter analysis of the flow process in transmission pipelines
Publikacjathe paper deals with the problem of early leak detection in transmission pipelines. First we present the derivation of state-space equations of the flow process in the pipelines. This description is then aggregated in order to obtain a principal model. Next, the problem of process model parameterization is addressed, taking into account the maximization of a model stability margin. The location of the maximum is determined using...
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Evolution of Ag nanostructures created from thin films: UV–vis absorption and its theoretical predictions
PublikacjaAg-based plasmonic nanostructures were manufactured by thermal annealing of thin metallic films. Structure and morphology were studied using scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM) and X-ray photoelectron spectroscopy (XPS). SEM images show that the formation of nanostructures is influenced by the initial layer thickness as well as the...
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The effect of gold shape and size on the properties and visiblelight-induced photoactivity of Au-TiO2
PublikacjatIn the present investigation, TiO2modified with a different geometry and size of gold particles, suchas nanospheres (NSPs), nanostars (NSTs) and nanorods (NRs), were prepared by the immobilizationmethod. The effect of the gold shape, size and TiO2matrix type (TiO2microspheres or rutile TIO-6 TiO2)were systematically investigated. The obtained photocatalysts were thoroughly characterized by UV–visdiffuse-reflectance spectroscopy...
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From structure to luminescence investigation of oxyfluoride transparent glasses and glass-ceramics doped with Eu3+/Dy3+ ions
PublikacjaGlasses and glass-ceramics with nominal composition 73 TeO2– 4BaO– 3Bi2O3–18SrF2-2RE2O3 (where RE = Eu, Dy) have been synthesized by conventional melt-quenching technique and subsequent heat treatment at 370 °C for 24 h in air atmosphere. Various Eu3+ to Dy3+ molar ratio have been applied to investigate luminescence properties in both glass and glass-ceramic matrices. Especially, white light emission through simultaneous excitation...
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Application of the Fractional Fourier Transform for dispersion compensation in signals from a fiber-based Fabry-Perot interferometer
PublikacjaOptical methods of measurement do not require contact of a probe and the object under study, and thus have found use in a broad range of applications such as nondestructive testing (NDT), where noninvasive measurement is crucial. Measuring the refractive index of a material can give a valuable insight into its composition. Low‑coherence radiation sources enable measurement of the sample’s properties across a wide spectrum, while...
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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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Considerations of Adaptive Digital Communications in Underwater Acoustic Channel
PublikacjaDown-link communication (DLC) and air transportable communication (ATAC) buoys as well as autonomous underwater vehicles (AUV) use acoustic links for gathering oceanographic data from underwater monitoring systems. The underwater channel propagation conditions are diverse in nature and require a special adaptive approach to the communication system design. The article presents a methodology for the communication systems design,...
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Measuring research on radio wave propagation
PublikacjaTelecommunication connections are increasingly based on the wireless links, both fixed and mobile, carried out under different radio systems. This kind of solution has many advantages. However, the propagation medium is a factor that causes many difficulties in designing wireless networks, because of large diversity of propagation environments. Transmission loss in each environment is determined by many variables phenomena and...
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Selection of C-Type Filters for Reactive Power Compensation and Filtration of Higher Harmonics Injected into the Transmission System by Arc Furnaces
PublikacjaThis article presents a method for selecting the elements of a C-type filter working with a conventional LC-type filter for compensating reactive power and filtering out higher harmonics generated by arc furnaces and ladle furnaces. The study was conducted in a steel mill supplied by a 110 kV transmission system, where higher harmonic currents and nonlinear loads were measured. A series of computer simulations were performed under...
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Assessment of Wooden Beams from Historical Buildings Using Ultrasonic Transmission Tomography
PublikacjaThe main goal of this study was non-destructive evaluation of wooden elements using ultrasonic waves. The inspection was carried out on wooden beams from a historical object. Elastic wave signals were processed by ultrasonic transmission tomography to obtain imaging of the internal structure of tested elements without disturbing their state and integrity. The focus was on the influence of wood anisotropy on the propagation of ultrasonic...
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Routing Method for Interplanetary Satellite Communication in IoT Networks Based on IPv6
PublikacjaThe matter of interplanetary network (IPN) connection is a complex and sophisticated topic. Space missions are aimed inter alia at studying the outer planets of our solar system. Data transmission itself, as well as receiving data from satellites located on the borders of the solar system, was only possible thanks to the use of powerful deep space network (DSN) receivers, located in various places on the surface of the Earth. In...
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Quality Evaluation of Speech Transmission via Two-way BPL-PLC Voice Communication System in an Underground Mine
PublikacjaIn order to design a stable and reliable voice communication system, it is essential to know how many resources are necessary for conveying quality content. These parameters may include objective quality of service (QoS) metrics, such as: available bandwidth, bit error rate (BER), delay, latency as well as subjective quality of experience (QoE) related to user expectations. QoE is expressed as clarity of speech and the ability...
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Laser-Assisted Synthesis and Oxygen Generation of Nickel Nanoparticles
PublikacjaNowadays, more than ever, environmental awareness is being taken into account when it comes to the design of novel materials. Herein, the pathway to the creation of a colloid of spherical, almost purely metallic nickel nanoparticles (NPs) through pulsed laser ablation in ethanol is presented. A complex description of the colloid is provided through UV-vis spectroscopy and dynamic light scattering analysis, ensuring insight into...
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A New Direct-Sequence Spread Spectrum Signal Detection Method for Underwater Acoustic Communications in Shallow-Water Channel
PublikacjaDirect-Sequence Spread Spectrum (DSSS) is one of the modulation and coding techniques used in Underwater Acoustic Communication (UAC) systems for reliable data transmision even at low signal levels. However, in a shallow water channel, there is a strong multipath propagation which causes a phase fluctuation of the received signal, affecting the performance of the spread-spectrum system. The article presents a differential method...
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Resonator-Loaded Waveguide Notch Filters with Broad Tuning Range and Additive-Manufacturing-Based Operating Frequency Adjustment Procedure
PublikacjaThis article presents a new class of ring-resonator-loaded waveguide notch filters with a broad tuning range, low cost, and improved performance. The proposed approach employs a comple-mentary asymmetric split ring resonator coupled to a microstrip transmission line and excited in a rectangular waveguide. An equivalent circuit model is proposed to explain the working principle of the proposed notch filter. The adjustment of the...
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Earth wires currents calculation by tableau analysis
PublikacjaThe paper presents a new method to compute a phase-to-earth fault current distribution in overhead transmission line. The method is based on the tableau analysis of an unbalanced, multi-wire model of a transmission line. It allows for the calculation of current distribution in overhead earth wires along the transmission line. Additionally, it may be used to calculate currents in a tower’s earthing system as well as voltages over...
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Measuring the density of DNA films using ultraviolet-visible interferometry
PublikacjaIn order to determine a proper value for the density of dry DNA films we have used a method based upon the measurement of interference effects in transmission spectra of thin DNA layers. Our results show that the methodology is effective and the density of DNA in this state, 1.407 g/cm3, is much lower than the commonly used 1.7 g/cm3. Obtaining accurate values for the DNA film density will allow the optical constants for DNA to...
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Towards Designing an Innovative Industrial Fan: Developing Regression and Neural Models Based on Remote Mass Measurements
PublikacjaThis article presents the process of the construction and testing a remote, fully autonomous system for measuring the operational parameters of fans. The measurement results obtained made it possible to create and verify mathematical models using linear regression and neural networks. The process was implemented as part of the first stage of an innovative project. The article presents detailed steps of constructing a system to...
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Performance analysis of data transmission in MC-CDMA radio interface with turbo codes
PublikacjaMulti-carrier code division multiple access (MC-CDMA) technique is a combination of two radio access techniques: CDMA and orthogonal frequency division multiplexing and has the advantages of both techniques. The paper presents the design of transmitter and receiver for MC-CDMA radio interface. It also presents encoders and decoders of turbo codes which were used in simulation of the MC-CDMA technique. Two turbo codes with 8-state...
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Stability evaluation of the marine propulsion unit mechanical system bymeans of vibrations measurements and their analysis.
PublikacjaIn paper selected issues concerning vibration diagnosis of the mechanical system within marine propulsion units have been given. The analysis of vibration parameters was carried out on the basis of experimental examinations of a real object in which an exceedance of the allowable vibration's level had been observed. In the beginning, the vibration apparatus being on laboratory equipment of the Department of Ship Power Plants of...
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Stability evaluation of the marine propulsion unit's mechanical system by means of vibration measurements and their analysis
PublikacjaIn this paper selected issues concerning vibration diagnosis of the mechanical system within marine propulsion units have been given. The analysis of vibration parameters was carried out on the basis of experimental examinations of a real object in which an exceedance of the allowable vibration's level had been observed. In the beginning, the vibration apparatus being on laboratory equipment of the Department of Ship Power Plants...
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A compact microstrip rat-race coupler constituted by nonuniform transmission lines
PublikacjaIn this work, a step-by-step development of a compact microstrip rat-race coupler (RRC) has been presented and discussed. A high degree of miniaturization has been obtained by substituting six quarter-wavelength uniform atomic building blocks of a RRC by their nonuniform counterparts. The miniaturization procedure has been realized in three progressive steps: (i) the first layout solution of a miniaturized RRC has been acquired...
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The study of Arduino Uno feasibility for DAQ purposes
PublikacjaUsing microcontroller systems becomes a routine in various measurement and control tasks. Their wide availability together with a huge potential of extending their functionality by additional modules allows developing advanced measuring and monitoring systems by non-specialists. However, using popular example codes often leads the user to pass over or not to be aware of the limitations of the system and drawing too far-reaching...
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Mono- and bimetallic (Pt/Cu) titanium(IV) oxide photocatalysts. Physicochemical and photocatalytic data of magnetic nanocomposites’ shell
PublikacjaSurface modification of titania with noble and semi-noble metals resulted in significant enhancement of photocatalytic activity. Presented data, showing the photocatalytic properties of TiO2-M (where M is Pt and/or Cu) photocatalysts were further used as Fe3O4@SiO2/TiO2-M magnetic nanocomposites shells in "Mono- and bimetallic (Pt/Cu) titanium(IV) oxide core-shell photocatalysts with Vis light activity and magnetic separability"...
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Performance of Coherent Modulation Scheme Used in Acoustic Underwater Communication System
PublikacjaThe development of an acoustic underwater communication system for shallow waters is still a big scientificand construction challenge. Currently, non-coherent modulations in combination with strong channel coding are used to achieve reliable communication with low rate in such a channel. To obtain transmission with a higher transmission rate, it is required to use coherent modulation. This paper presents the assumptions of such...
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Study Analysis of Transmission Efficiency in DAB+ Broadcasting System
PublikacjaDAB+ is a very innovative and universal multimedia broadcasting system. Thanks to its updated multimedia technologies and metadata options, digital radio keeps pace with changing consumer expectations and the impact of media convergence. Broadcasting analog and digital radio services does vary, concerning devices on both transmitting and receiving side, as well as content processing mechanisms. However, the biggest difference is...
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Photoactivity of decahedral TiO2 loaded with bimetallic nanoparticles: Degradation pathway of phenol-1- 13 C and hydroxyl radical formation
PublikacjaDecahedral TiO2decorated with bimetallic nanoparticles were synthesized via radiolysis and photode-position method. The effect of bimetallic surface composition (Ag Pt, Ag Au, Au Pd, Au Pt) as well asdeposition technique (simultaneous or sequential) on the photocatalytic activity in phenol degradationand efficiency of hydroxyl radicals generation under UV–vis light irradiation were investigated. Modifiedand pristine decahedral...
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Structural Health Monitoring of Overhead Power Transmission Lines
PublikacjaStructural Health Monitoring (SHM) is a novel and continuously developing branch of science and technology that draws attention of scientists all over the world. It creates opportunities to detect, localize and identify structural damage of various types such as: line breakage, permissible sag, bolt loosening, fatigue cracking or insulator contamination. On the other hand the methods used to estimate the remaining operational...
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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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Reduction of the Multipath Propagation Effect in a Hydroacoustic Channel Using Filtration in Cepstrum
PublikacjaDuring data transmission in a hydroacoustic channel, one of the problems is the multipath propagation effect, which leads to a decrease in the transmission parameters and sometimes completely prevents it. Therefore, we have attempted to develop a method, which is based on a recorded hydroacoustic signal, that allows us to recreate the original (generated) signal by eliminating the multipath effect. In our method, we use cepstral...
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Fiber optic low-coherence Fabry-Pérot interferometer with ZnO layers in transmission and reflective mode: comparative study
PublikacjaA construction of a low-coherence fiber-optic Fabry-Pérot interferometer using a thin ZnO layer as a reflective surfaces was proposed and examined. In the investigated setup, the ZnO layer of thickness 200 nm were deposited on the face of the standard telecommunication single-mode optical fiber (SMF-28). Measurements of interference signal were performed for the interferometer working in the transmission and reflective mode, as...
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Spectral reflectance and transmission modeling of multi-cavity Fabry-Pérot interferometer with ZnO thin films
PublikacjaIn this paper spectral reflectance and transmission of a low-coherence fiber-optic Fabry-Pérot interferometer with thin ZnO layers is analyzed using a multi-cavity approach. In the investigated setup two standard single-mode optical fibers (SMF-28) with thin ZnO films deposited on their end-faces form an extrinsic Fabry-Pérot interferometer with air cavity. Calculations of the spectral response of the interferometer were performed...
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Mobile wireless measurement system for potatoes storage management
PublikacjaThe paper discusses the idea and the design of a remote control system for a storage management of agricultural products which temperature may rise in a result of biological processes during the storage. Exemplary potatoes storehouse is discussed as an application of the automation system. Because of existing buildings and infrastructure in the farm, wireless data transfer system has been proposed for both sensors to data acquisition...
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Multimedia System for Environmental Noise Monitoring. [Multimedialny System Monitorowania Hałasu Środowiskowego]
PublikacjaIntroductionNumerous reports relating to noise threats in Poland indicate that they occur commonly. The noise has an enormous impact on the health and life quality of the human beings. Noise pollution in Poland is greater than in others UE countries, moreover it has been increased recently. Taking into account 2002/49/WE directive related to the control and assessment of environmental noise a necessity of monitoring these threats...
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Implementation of an Adaptive Method for Changing the Frequency Division of the Counter Clock Signal in a Frequency-to-Code Converter
PublikacjaProcessing physical quantities into an indirect signal is a standard method of transferring information about the measured quantity to the master system, which analyzes the data obtained from the acquisition system. The intermediate signal is very often the voltage, but another transmission medium can be the frequency of the output signal of the “physical quantity-to-frequency” converter. The article presents the implementation...
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Comparison of Doppler Effect Estimation Methods for MFSK Transmission in Multipath Hydroacoustic Channel
PublikacjaUnderwater wireless communication remains a challenging topic, particularly for applications such as wreck penetration where multipath and Doppler effects are very intense. These effects are becoming even more difficult to mitigate for fast data transmission systems that utilize wideband signals. Due to the low propagation speed of acoustic wave in the water, there is a significant difference between the Doppler shift for lower...
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Design of a compact planar transmission line for miniaturized rat-race coupler with harmonics suppression
PublikacjaThis paper presents an elegant yet straightforward design procedure for a compact rat-race coupler (RRC) with an extended harmonic suppression. The coupler’s conventional λ/4 transmission lines (TLs) are replaced by a specialized TL that offers significant size reduction and harmonic elimination capabilities in the proposed approach. The design procedure is verified through the theoretical, circuit, and electromagnetic (EM) analyses,...
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Adaptive Method of Raster Images Compression and Examples of Its Applications in the Transport Telematic Systems
PublikacjaThe paper presents a concept and exemplary application of an adaptive method of compression of raster images which may be applied, i.a. in ITS systems. The described method allows to improve the efficiency of systems belonging to ITS category, which require transmission of large volumes of image data through telecommunications networks. The concept of the adaptive method of compression of raster images described in the paper uses...
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Inline Microwave Filters With N+1 Transmission Zeros Generated by Frequency-Variant Couplings: Coupling-Matrix-Based Synthesis and Design
PublikacjaA general coupling-matrix-based synthesis methodology for inline Nth-order microwave bandpass filters (BPFs) with frequency-variant reactive-type couplings that generate N+1 transmission zeros (TZs) is presented in this brief. The proposed approach exploits the formulation of the synthesis problem as three inverse nonlinear eigenvalue problems (INEVPs) so that the coupling matrix is built from their sets of eigenvalues. For this...
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Reliability assessment of an OVH HV power line truss transmission tower subjected to seismic loading
PublikacjaThe study focuses on the reliability of a transmission tower OS24 ON150 + 10, an element of an OVH HV power line, under seismic loading. In order to describe the seismic force, the real-life recording of the horizontal component of the El Centro earthquake was adopted. The amplitude and the period of this excitation are assumed random, their variation is described by Weibull distribution. The possible space state of the phenomenon...
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Case studies of resonance phenomena in high voltage overhead power lines with shunt reactors
PublikacjaMisguided design of the towers of power transmission lines can lead to serious problems such as voltage asymmetry, overvoltages, electric arc extinction difficulties or resonance – in case of double circuit line with shunt reactors. The paper points out those threats on example of 400 kV double circuit overhead transmission line with shunt reactors.
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Comparative Analysis of Reactive Power Compensation Devices in a Real Electric Substation
PublikacjaA constant worldwide growing load stress over a power system compelled the practice of a reactive power injection to ensure an efficient power network. For this purpose, multiple technologies exist in the knowledge market out of which this paper emphasizes the usage of the flexible alternating current transmission system (FACTS) and presents a comparative study of the static var compensator (SVC) with the static synchronous compensator...
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Preparation and characterization of Pt–N/TiO2 photocatalysts and their efficiency in degradation of recalcitrant chemicals
PublikacjaSeries of Pt–N/TiO2 photocatalysts were synthesized using the sol–gel method. The photocatalysts’ characteristics by X-ray diffractometry (XRD), scanning transmission electron microscopy (STEM), diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS) showed that sample with the molar ratio Ti:N equal 1:4 and platinum nanoparticles size of about 3 nm had anatase structure, about 94 m2/g specific surface area...
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LTE and NB-IoT Performance Estimation Based on Indicators Measured by the Radio Module
PublikacjaMonitoring the operating parameters of power grids is extremely important for their proper functioning as well as for ensuring the security of the entire infrastructure. As the idea of the Internet of Things becomes more ubiquitous, there are tools for monitoring the state of the complex electrical grid and means to control it. There are also developed new measuring devices and transmission technologies allowing for the transfer...
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Monometallic nanoparticles decorated and rare earth ions doped KTaO3/K2Ta2O6 photocatalysts with enhanced pollutant decomposition and improved H2 generation
PublikacjaNew, monometallic nanoparticles (MNPs) decorated surface and rare earth (RE) ions doped lattice of perovskite-type (KTaO3)/pyrochlore-type (K2Ta2O6) photocatalysts were successfully prepared by facile hydrothermal incorporation of RE ions into KTaO3/K2Ta2O6 lattices followed by photodeposition of MNPs. The impact of noble metal type (MNPs = Au, Pt, Rh) and rare earth dopant type (RE = Er, Pr) on the physicochemical properties correlated...