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Wydział Elektroniki, Telekomunikacji i Informatyki
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Rok 2025
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Selective light-activation of sensing regions in hybrid Au-graphene-TiO2 chemiresistive gas sensor
PublikacjaControlling the sensing activity of novel gas sensors is a desirable and simultaneously challenging issue. In this work, ink-printed graphene-based hybrid sensors are demonstrated, and the possibility of selective activation of gas-sensitive components with light is presented. Graphene flakes were mixed with TiO2 nanoparticles and decorated with Au nanoparticles to produce sensors of photocatalytic and plasmonic properties (Au-G-TiO2)....
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Self-Isolation in MIMO Array Using Mode Diversity
PublikacjaA new isolation technique is proposed for multiple-input multiple-output (MIMO) microstrip patch antenna (MPA) arrays utilizing mode’s diversity. Typically, similar modes are excited in each element of the MIMO array. However, the proposed MIMO array uses two elements of different sizes excited in distinct modes at the same frequency. It is found that the TM01 mode excited in one MPA, a hybrid mode (TM03+TM21) is induced in the...
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Sensing of NO2, NH3, and C3H6O by graphene-Si Schottky diode at chosen voltage biases
PublikacjaOur research aims to propose a selective gas sensor based on a single graphene-silicon Schottky junction. By polarizing the sensor with selected voltage, we move between different regions of its gas sensitivity dependent on the lighting conditions. Our results show that low detection limits (36 ppb for NO2, 238 ppb for NH3, and 640 ppb for C3H6O) are obtained under UV irradiation at -0.4 V; however, a light source power supply...
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Separation of Simultaneous Speakers with Acoustic Vector Sensor
PublikacjaThis paper presents a method of sound source separation in live audio signals, based on sound intensity analysis. Sound pressure signals recorded with an acoustic vector sensor are analyzed, and the spectral distribution of sound intensity in two dimensions is calculated. Spectral components of the analyzed signal are selected based on the calculated source direction, which leads to a spatial filtration of the sound. The experiments...
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Serverless–edge computing with mobile document agents
PublikacjaExchange of documents as email attachments in collaborative decision making lacks support for keeping track ofthreads of performed activities, which often leads to email overload and strain. A proactive document email attach-ment linking the passive content and active services could build reproducibility in collaborative processes, even ifworkers may tend to exchange emails indiscriminately. The key role in achieving this is...
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Speech intelligibility improvement for public address systems in noisy environments based on automatic gain selection in octave bands
PublikacjaA method of speech intelligibility improvement in public address (PA) systems installed in reverberant acoustic spaces is proposed. The method is mainly intended for systems operating in high background noise levels. The algorithm is based on the near end listening enhancement approach. Signal-to-noise ratio (SNR) is evaluated in the octave frequency bands. Signal levels in the acoustic space are estimated using the measured impulse...
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Strategies for feature-assisted development of topology agnostic planar antennas using variable-fidelity models
PublikacjaDesign of antennas for contemporary applications presents a complex challenge that integrates cognitive-driven topology development with the meticulous adjustment of parameters through rigorous numerical optimization. Nevertheless, the process can be streamlined by emphasizing the automatic determination of structure geometry, potentially reducing the reliance on traditional methods that heavily rely on engineering insight in the...
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Surrogate modeling of passive microwave circuits using recurrent neural networks and domain confinement
PublikacjaElectromagnetic (EM) simulation is widespread in microwave engineering. EM tools ensure evaluation reliability but incur significant expenses. These can be mitigated by employing surrogate modeling methods, especially to expedite design workflows like local/global optimization or uncertainty quantification. However, building accurate surrogates is a daunting task beyond simple cases (low dimensionality, narrow geometry parameter...
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Survey of Asynchronous Radiolocation Methods
PublikacjaThis publication reviews asynchronous radiolocation methods, emphasizing their analytical descriptions. Radiolocation systems evolve through the integration of advancements from multiple scientific disciplines, including telecommunications, computer science, electronics, and digital signal processing, making them inherently interdisciplinary. Most existing literature focuses on radiolocation systems with synchronized reference...
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System of gas detection by two-dimensional materials
PublikacjaThis thesis demonstrates light-assisted gas sensing by low-dimensional structures (graphene and two-dimensional metal chalcogenides). Studies on the prototype graphene-based resistive sensors show that the configuration of the device and the used substrate affect sensing properties. The sensors with Schottky diode configuration with graphene deposited directly on silicon exhibited high sensitivity and stability at lower voltage...
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The Impact of 8- and 4-Bit Quantization on the Accuracy and Silicon Area Footprint of Tiny Neural Networks
PublikacjaIn the field of embedded and edge devices, efforts have been made to make deep neural network models smaller due to the limited size of the available memory and the low computational efficiency. Typical model footprints are under 100 KB. However, for some applications, models of this size are too large. In low-voltage sensors, signals must be processed, classified or predicted with an order of magnitude smaller memory. Model downsizing...
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Toward 6G Optical Fronthaul: A Survey on Enabling Technologies and Research Perspectives
PublikacjaThe anticipated launch of the Sixth Generation (6G) of mobile technology by 2030 will mark a significant milestone in the evolution of wireless communication, ushering in a new era with advancements in technology and applications. 6G is expected to deliver ultra-high data rates and almost instantaneous communications, with three-dimensional coverage for everything, everywhere, and at any time. In the 6G Radio Access Networks (RANs)...
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Tuning charge transport in polydopamine tetramers via oxidation state and orientation in supramolecular junctions with gold contacts: An ab initio DFT study
PublikacjaThis work presents a comprehensive computational investigation of gold-polydopamine supramolecular junctions and their electronic properties using density functional theory (DFT) and non-equilibrium Green's functions (NEGF) methodology. Non-covalent interactions between gold and PDA models are described in the slab configuration, and the molecular junction. By modulating the oxidation state, molecular structure, and surface arrangements...
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Two Approaches to Constructing Certified Dominating Sets in Social Networks
PublikacjaSocial networks are an important part of our community. In this context, certified dominating sets help to find in networks a group of people, referring as officials, such that 1) for each civilian, there is an official that can serve the civilian, and 2) no official is adjacent to exactly one civilian, to prevent potential abuses. To delve deeper into this topic, this study considers two approaches to the problem of finding certified...
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Ultra-Compact Quintuple-Band Terahertz Metamaterial Biosensor for Enhanced Blood Cancer Diagnostics
PublikacjaCancer and its diverse variations pose one of the most significant threats to human health and well-being. One of the most aggressive forms is blood cancer, originating from bone marrow cells and disrupting the production of normal blood cells. The incidence of blood cancer is steadily increasing, driven by both genetic and environmental factors. Therefore, early detection is crucial as it enhances treatment outcomes and improves...
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Uncovering the electrochemical processes and understanding the causes of the degradation via EIS-DRT in large-scale solid oxide fuel cell
PublikacjaInducing changes in performance and observation of electrochemical processes is quite easy to do using ‘button cells’, which are the favorite objects in most research studies. Unfortunately, those cells may sometimes provide misleading outcomes or lead to promising results, applicable only on small scale, belittling their technological value. In this study, a large-scale SOFC with a 100 cm2 cathode active surface area was subjected...
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UNRES web server: Extensions to nucleic acids, prediction of peptide aggregation, and new types of restrained calculations
PublikacjaThe third version of the UNRES web server is described, in which the range of biological macromolecules treated and calculation types has been extended significantly. DNA and RNA molecules have been added to enable the user to run simulations of their folding/hybridization and dynamics. To increase the accuracy of the simulated proteins models, the restraints on secondary structure have been enhanced to include the probabilities...
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Unsupervised Design and Geometry Optimization of High-Sensitivity Ring-Resonator-Based Sensors
PublikacjaIn this study, we introduce a technique for unsupervised design and design automation of resonator-based microstrip sensors for dielectric material characterization. Our approach utilizes fundamental building blocks such as circular and square resonators, stubs, and slots, which can be adjusted in size and combined into intricate geometries using appropriate Boolean transformations. The sensor's topology, including its constituent...
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Usability Issues With Mobile Applications: Insights From Practitioners and Future Research Directions
PublikacjaThis study is motivated by two key considerations: the significant benefits mobile applications offer individuals and businesses, and the limited empirical research on usability challenges. To address this gap, we conducted structured interviews with twelve experts to identify common usability issues. Our findings highlight the top five concerns related to: information architecture, user interface design, performance, interaction...
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UV light-activated gas mixture sensing by ink-printed WS2 layer
PublikacjaWe fabricated a sensing layer from ink-printed WS2 flakes and utilized it for UV-activated gas sensing. The optical imaging of the structure made by repeated printing revealed the continuous layer comprising sub-µm flakes, confirmed independently by small-area AFM images (1×1 µm2). The activity of the sensing surface was investigated locally via AFM scanning of the surface with a polarized probing tip. The results indicated that...
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Vehicle Type Recognition Based on Audio Data
PublikacjaIdentifying different vehicle types can help manage traffic more efficiently, reduce congestion, and improve public safety. This study aims to create a classification model that can recognize vehicle types based on the sound of passing vehicles. To achieve this, a database of raw audio files containing 1763 samples from two sources was assembled. The time-domain signals were converted to a time-frequency representation using the...
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Wideband High Efficiency Slot Array Antenna Based on Gap Waveguide Single-Layer Feeding Network
PublikacjaA single-layer, full metal, wideband and high efficiency slot array antenna operating in V-band (50-75 GHz) is proposed using single corporate-feeding network based on gap waveguide (GW) technology. Compared with conventional multi layered slot array antenna, the proposed antenna utilizes only one waveguide feeding layer excites the radiation slots, therefore the assembly complexity of multi-layer waveguide and manufacturing cost...
Rok 2024
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3-D Printable Metal-Dielectric Metasurface for Risley Prism-Based Beam-Steering Antennas
PublikacjaA 3-D printable, planar, metal-dielectric metasurface-based, 2-D beam-steering system for aperture-type antennas is presented in this paper. This beam steering system, also known as the near-field meta-steering system, comprises two fully passive phase-gradient metasurfaces placed in the antenna’s nearfield region to steer the radiation beam. To address the non-uniform electric field phase of the aperture antenna, phase correction...
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3D-Breast System for Determining the Volume of Tissue Needed for Breast Reconstruction
Publikacja3D imaging systems can be used to effectively determine breast volumes for surgical applications. This article presents methods for surface reconstruction and volume determination based on the point cloud created by 3D imaging. Such a system would be used to accurately estimate breast volume in patients classified for breast reconstruction surgery at plastic surgery centers. To develop such a system, various methods of determining...
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A 0.5 V Nanowatt Biquadratic Low-Pass Filter with Tunable Quality Factor for Electronic Cochlea Applications
PublikacjaA novel implementation of an analogue low-power, second-order, low-pass filter with tunable quality factor (Q) is presented and discussed. The filter feature is a relatively simple, buffer-based, circuit network consisting of eleven transistors operating in a subthreshold region. Q tuning is accomplished by injecting direct current into a network node, which changes the output resistance of the transistors and, as a result, modifies...
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A Compact Circularly Polarized Dielectric Resonator Antenna with MIMO Characterizations for UWB Applications
PublikacjaUltra-wideband (UWB) technology is extensively used in indoor navigation, medical applications, and Internet of Things (IoT) devices due to its low power consumption and resilience against multipath fading and losses. This paper examines a multiple input multiple-output (MIMO), circularly polarized (CP) dielectric resonator antenna (DRA) for UWB systems. Compact form factor, high gain, wideband response, improved port isolation,...
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A Comparison of Directional Beamforming Capabilities: High-Order Ambisonic Microphone vs. Shotgun Microphones
PublikacjaThis article presents the practical implications of the directional beamforming capability of a higher-order ambisonic microphone compared with popular shotgun microphones. Five different microphones were used in the study: Sennheiser MKH 416, Rode NTG2, Panasonic AG-MC200, Zoom SGH-6, and Zylia ZM-1 (ambisonic microphone). The results highlight the versatility of higher-order ambisonics for non-immersive use, which allows for...
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A Data-Driven Comparative Analysis of Machine-Learning Models for Familial Hypercholesterolemia Detection
PublikacjaThis study presents an assessment of familial hypercholesterolemia (FH) probability using different algorithms (CatBoost, XGBoost, Random Forest, SVM) and its ensembles, leveraging electronic health record data. The primary objective is to explore an enhanced method for estimating FH probability, surpassing the currently recommended Dutch Lipid Clinic Network (DLCN) Score. The models were trained using the largest Polish cohort...
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A gap waveguide-based mechanically reconfigurable phase shifter for high-power Ku-band applications
PublikacjaThis paper presents a novel design of a low-loss, reconfgurable broadband phase shifter based on groove gap waveguide (GGW) technology. The proposed phase shifter consists of a folded GGW and three bends with a few pins forming the GGW and one bend attached to a movable plate. This movable plate allows for adjustments to the folded waveguide length, consequently altering the phase of electromagnetic waves. The advantage of GGW...
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A high-gain gap waveguide-based 16 × 16 slot antenna array with low sidelobe level for mmwave applications
PublikacjaThis study presents the design of a high-gain 16 × 16-slot antenna array with a low sidelobe level (SLL) using a tapered ridge gap waveguide feeding network for Ka-band applications. The proposed antenna element includes four cavity-backed slot antennas. A tapered feeding network is designed and utilized for unequal feeding of the radiating elements. Ridge gap waveguide technology is used to reduce the feeding network loss and...
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A Highly Compact Split Ring Resonator Based Rectangular Dielectric Resonator Antenna with Multiband Characterization
PublikacjaThis work encompasses a novel highly compact Split Ring Resonator (SRR) based quad-band Dielectric Resonator Antenna (DRA) for 4G and 5G applications. The proposed antenna comprises of an extended rectangular feedline and a rectangular DR in combination with two SRRs. The DRA uses the extended rectangular microstrip feedline for providing better impedance matching and enhanced performance. Remarkably, the introduction of SRRs on...
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A learning community model: the Center for Innovative Education supporting academic didactics at Gdańsk University of Technology, Poland
PublikacjaThe current digital transformation requires academics to apply their pedagogical and technological skills to their teaching and professional development to address the newly emerging needs of the digital era. This study aims to analyse the operating model of the Center for Innovative Education (CIE) at Gdańsk University of Technology (Gdańsk Tech), Poland, as an incubator for professional development of academic staff at Gdańsk...
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A Low-Profile 3-D Printable Metastructure for Performance Improvement of Aperture Antennas
PublikacjaIn order to increase the radiation performance of aperture-type antennas, this paper demonstrates a low-profile, planar, single-layer, three-dimensional (3-D) printable metastructure. The proposed hybridized metastructure is highly transparent as it is made out of novel hybrid meta-atoms having transmission coefficient magnitudes greater than -0.72 dB and fully complies with the near-field phase transformation principle. The hybridized...
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A Low-Profile Metal-backed Dipole Loaded with Closely Coupled Arc-shaped Open Stubs for On-metal Tag Design with Wide Frequency Tuning Capability
PublikacjaThis research has presented a single-layer metal-backed dipole antenna, which consists of a feedline loaded with two pairs of closely-coupled arc-shaped open stubs, for designing a metal-mountable tag that features tuning capability over a wide range of frequency. Here, the stubs can generate sufficient inductive reactance for bringing down the tag resonant frequency tunable in both the regulated UHF RFID passbands (North American...
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A Machine Learning Approach for Estimating Overtime Allocation in Software Development Projects
PublikacjaOvertime planning in software projects has traditionally been approached with search-based multi-objective optimization algorithms. However, the explicit solutions produced by these algorithms often lack applicability and acceptance in the software industry due to their disregard for project managers' intuitive knowledge. This study presents a machine learning model that learns the preferred overtime allocation patterns from solutions...
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A machine learning approach to classifying New York Heart Association (NYHA) heart failure
PublikacjaAccording to the European Society of Cardiology, globally the number of patients with heart failure nearly doubled from 33.5 million in 1990 to 64.3 million in 2017, and is further projected to increase dramatically in this decade, still remaining a leading cause of morbidity and mortality. One of the most frequently applied heart failure classification systems that physicians use is the New York Heart Association (NYHA) Functional...
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A Mammography Data Management Application for Federated Learning
PublikacjaThis study aimed to develop and assess an application designed to enhance the management of a local client database consisting of mammographic images with a focus on ensuring that images are suitably and uniformly prepared for federated learning applications. The application supports a comprehensive approach, starting with a versatile image-loading function that supports DICOM files from various medical imaging devices and settings....
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A modified DC Hebb–Wagner polarization method for determining the partial protonic electrical conductivity in mixed-conducting BaGd0.3La0.7Co2O6−δ
PublikacjaIn this work, partial protonic conductivity in mixed conducting (BZCY721) and BaGd0.3La0.7Co2O6−d (BGLC137) was studied. For this purpose, a modified DC Hebb–Wagner polarization method was used. A four-wire type of galvanic cell as well as a suitable calculation model was applied. The method was validated using proton conducting electrolyte – BaZr0.7Ce0.2Y0.1O3−d – as a reference material. For the first time, protonic partial conductivity...
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A Novel Device and System for Fall Detection Under the Shower
PublikacjaIn this paper, device construction and preliminary results for shower safety assistance are presented. The device allows monitoring of shower-taking persons without violating privacy and intimacy, while it has the ability to detect a persons entering and leaving the shower and detecting fall conditions. It allows better supervision of elders living independently at their locations.
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A Novel Iterative Decoding for Iterated Codes Using Classical and Convolutional Neural Networks
PublikacjaForward error correction is crucial for communication, enabling error rate or required SNR reduction. Longer codes improve correction ratio. Iterated codes offer a solution for constructing long codeswith a simple coder and decoder. However, a basic iterative code decoder cannot fully exploit the code’s potential, as some error patterns within its correction capacity remain uncorrected.We propose two neural network-assisted decoders:...
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A Planar-Structured Circularly Polarized Single-Layer MIMO Antenna for Wideband Millimetre-Wave Applications
PublikacjaIn this paper, a simple geometry, planar-structured printed multiple-input-multiple-output (MIMO) antenna utilizing dual circular polarization (CP) is presented. The proposed numerically and experimentally validated design features a fully grounded coplanar waveguide (CPW) and a systematically perturbed feedline radiator. The fringing electric (E) field along the feedline is altered by extruding periodic stubs on each side of the...
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A Probabilistic Optimisation Approach to the Equitable Controller Location Problem
PublikacjaThe ability of the Software-Defined Network (SDN) to transport traffic flows depends, in particular, on the SDN switches being able to communicate with SDN controllers, which are responsible for the setup of network connections and the configuration of switches. Since in principle the number of SDN controllers is limited they must be installed in a set of carefully selected node locations. Whereas the problem of controller placement...
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A procedure for the visualization of fingerprint traces on standard and thermal paper using the electron excitation energy of 1,8-diazafluoren-9- one aggregates in a polyvinylpyrrolidone polymer
PublikacjaThe scope of this study is a new procedure for visualizing dactyloscopic traces on an absorbent surface using a solution based on aggregates of 1,8-diazafluoren-9-one (DFO) in a polyvinylpyrrolidone polymer (PVP). An absorbent surface is defined as a plain or thermal paper, which is considered to be a difficult surface due to its varying chemical composition. In the case of the thermal paper surface, the procedure can be further...
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A prototype information system for managing and pricing e-waste
PublikacjaThere is no doubt that innovation drives development in all areas of human activity, including electrical and electronic equipment. However, the production of new equipment has a significant impact on the natural environment and a relatively high consumption of natural resources. To address these issues, the circular economy has been implemented in recent years by promoting and introducing numerous measures to facilitate the recycling...
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A review of explainable fashion compatibility modeling methods
PublikacjaThe paper reviews methods used in the fashion compatibility recommendation domain. We select methods based on reproducibility, explainability, and novelty aspects and then organize them chronologically and thematically. We presented general characteristics of publicly available datasets that are related to the fashion compatibility recommendation task. Finally, we analyzed the representation bias of datasets, fashion-based algorithms’...
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A Review on Machine Learning Deployment Patterns and Key Features in the Prediction of Preeclampsia
PublikacjaPrevious reviews have investigated machine learning (ML) models used to predict the risk of developing preeclampsia. However, they have not addressed the intended deployment of these models throughout pregnancy, nor have they detailed feature performance. This study aims to provide an overview of existing ML models and their intended deployment patterns and performance, along with identified features of high importance. This review...
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A Selection of Starting Points for Iterative Position Estimation Algorithms Using Feedforward Neural Networks
PublikacjaThis article proposes the use of a feedforward neural network (FNN) to select the starting point for the first iteration in well-known iterative location estimation algorithms, with the research objective of finding the minimum size of a neural network that allows iterative position estimation algorithms to converge in an example positioning network. The selected algorithms for iterative position estimation, the structure of the...
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A simple route of providing a soft interface for PEDOT: PSS film metallic electrodes without loss of their electrical interface parameters
PublikacjaThe work presents the development of a soft interface at PEDOT:PSS film without changing its electrical interface parameters. In the first step, PEDOT:PSS is electrodeposited on the commercial platinum electrode under the state-of-the-art conditions desirable for different electrochemical electrodes. Secondly, a pure hydrogel layer is deposited on the top of the electrodeposited PEDOT:PSS film under conditions that provide desirable...
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A simplified channel estimation procedure for NB-IoT downlink
PublikacjaThis paper presents a low-complexity channel estimation procedure which is suitable for use in energy-efficient NB-IoT user equipment devices. The procedure is based on the well-established least squares scheme, followed by linear interpolation in the time domain and averaging in the frequency domain. The quality of channel estimation vs. signal-to-noise ratio is evaluated for two channel models and compared with the performance...
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A Survey on the Datasets and Algorithms for Satellite Data Applications
PublikacjaThis survey compiles insights and describes datasets and algorithms for applications based on remote sensing. The goal of this review is twofold: datasets review for particular groups of tasks and high-level steps of data flow between satellite instruments and end applications from an implementation and development perspective. The article outlines the generalized data processing pipelines, taking into account the variations in...