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Catalog Publications
Year 2025
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A Highly Compact Low-Profile Beam Switching Transmitarray Antenna for ISM-Band Applications
PublicationThis paper presents a novel, very low-profile transmitarray antenna (TA) designed specifically for applications in the 24 GHz Industrial, Scientific, and Medical (ISM) band. The design innovation lies in embedding the switchable feed antenna into the beam-focusing surface and adding a reflector, which effectively halves the antenna’s size in the boresight direction. This compact antenna allows for easy beam switching through the...
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A Miniaturized and High Optically Transparent Frequency Selective Surface for RF Shielding using Double-Glazed Glass Windows for Green Building Applications
PublicationThis research presents a miniaturized and high optically transparent (OT) frequency selective surface (FSS) for achieving RF shielding through glass window panels. The proposed FSS consists of a single-layered copper pattern sandwiched between two ordinary glass substrates to suppress the dual bands of sub-6 fifth generation (5G). In particular, the design effectively shields n65-downlink (2.1 GHz) and a portion of n78-band (3.5...
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A Non-PCM-Based 2 × 2 MIMO Antenna Array With Low Radar Cross-Section Using Characteristic Mode Analysis
PublicationIn this paper, we introduced a 2×2 multiple-input-multiple-output (MIMO) antenna array using a non-polarization conversion metasurface (NPCM) with reduced radar cross section (RCS). To achieve a low RCS, a chess-board configuration is typically adopted. However, in conventional NPCM designs, subarrays with 180◦ phase shifts apart exhibit radiating modes at different resonance frequencies due to varied unit cell sizes and spacing....
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AI-Driven Sustainability in Agriculture and Farming
PublicationIn this chapter, we discuss the role of artificial intelligence (AI) in promoting sustainable agriculture and farming. Three main themes run through the chapter. First, we review the state of the art of smart farming and explore the transformative impact of AI on modern agricultural practices, focusing on its contribution to sustainability. With this in mind, our analysis focuses on topics such as data collection and storage, AI...
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An 8–18 GHz ultrawideband gap waveguide folded bandpass filter for radar applications
PublicationThe present work introduces a compact ultrawideband filter based on folded ridge gap waveguide. The design and fabrication of a ninth-order bandpass filter demonstrates its capabilities, achieving a 75 % fractional bandwidth, a return loss (RL) of 17.6 dB, and an insertion loss (IL) of 0.52 dB within the 8.22 to 18.15 GHz frequency range. The fabricated prototype shows excellent agreement between simulations and measurements. The...
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An All-Metal Broadband Low SLL slot array antenna for use in 5G Sub-6 GHz networks
PublicationThis paper describes the design and implementation of an all-metal wideband cavity-backed slot array antenna specifically optimized for 5G sub-6GHz networks. The antenna is engineered to feature low sidelobe levels (SLL), which enhance signal clarity and reduce interference. The proposed antenna utilizes a novel approach, directly exciting all radiating slots through the cavity layer, thus eliminating the need for a complex and...
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An ultrawideband monopulse feed with slant polarization for tracking radar systems
PublicationAn ultrawideband slant-polarized monopulse feed is designed and fabricated for microwave applications. The proposed configuration features four end-launched diagonal horns allowing for the production of sum and difference channels in two principal planes. The key advantage of this proposed monopulse antenna over traditional monopulse feeds is its ability to combine the benefits of ultrawideband performance with slant polarization...
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Anterior prefrontal EEG theta activities indicate memory and executive functions in epilepsy patients
PublicationObjective: Cognitive deficits are one of the most debilitating comorbidities in epilepsy and other neurodegenerative, neuropsychiatric, and neurodevelopmental brain disorders. Current diagnostic and therapeutic options are limited and lack objective measures of the underlying neural activities. In this study, electrophysiological biomarkers that reflect cognitive functions in clinically validated batteries were determined to aid...
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Automatic Cleaning of Time Series Data in Rural Internet of Things Ecosystems That Use Nomadic Gateways
PublicationA serious limitation to the deployment of IoT solutions in rural areas may be the lack of available telecommunications infrastructure enabling the continuous collection of measurement data. A nomadic computing system, using a UAV carrying an on-board gateway, can handle this; it leads, however, to a number of technical challenges. One is the intermittent collection of data from ground sensors governed by weather conditions for...
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CeO2/La2O3/MWCNTs as an efficient nano-electrocatalyst for use in the anode of alcohol fuel cells
PublicationOne of the most important challenges in commercializing Direct Alcohol Fuel Cells (DAFCs) is the significant expense of advanced catalysts used in their anodes and cathodes and the CO poisoning of these catalysts with alcohol oxidation by-products. Alcohols oxidation reaction occurred in the anode of DAFCs. Within this study, a tripartite catalyst, comprising cerium oxide (CeO2) and lanthanum oxide (La2O3) integrated with multi-walled...
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Cost-Efficient Behavioral Modeling of Antennas by Means of Global Sensitivity Analysis and Dimensionality Reduction
PublicationComputational tools, particularly electromagnetic (EM) solvers, are now commonplace in antenna design. While ensuring reliability, EM simulations are time-consuming, leading to high costs associated with EM-driven procedures like parametric optimization or statistical design. Various techniques have been developed to address this issue, with surrogate modeling methods garnering particular attention due to their potential advantages....
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D-Band High Gain Planer Slot Array Antenna using Gap Waveguide Technology
PublicationA D-band high gain slot array antenna with corporate-fed distribution network based on gap waveguide structures is proposed at 140GHz. To overcome the fabrication challenges at such high frequency, the gap waveguide technology is deployed in which good electrical contact between different parts of the waveguide structure is not required. The proposed sub-array has four radiating slots that are excited by a groove gap cavity and...
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Declarative ship arenas under favourable conditions
PublicationAccording to maritime regulations, a collision-avoidance action shall be taken at an “ample time” while strict interpretation of this term is ambiguous. Evasive manoeuvres, executed by marine navigators on a daily basis, are usually carried out well in advance, while the distance at which they decide to perform such a manoeuvre is mostly subjective and results, e.g., from the navigator's seagoing experience. A proper understanding...
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Dermoscopy of External Ear Melanocytic Lesions: Performance of Selected Dermoscopic Screening Algorithms and Proposal of a New Predictive Model for Malignancy (AuriCheck Dermoscopic Algorithm)
PublicationBackground/Objectives: External ear melanocytic lesions (EEMLs) are frequently encountered in clinical practice. EEMLs belong to dermoscopic special site locations and their dermoscopic presentation is poorly characterized. The aims of the study were to determine the dermoscopic features and patterns of EEMLs, to evaluate the performance of selected dermoscopic screening algorithms for EEML and to propose a dedicated site-specific...
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Dynamic anaerobic digestion-based biorefineries for on-demand renewable energy and bioproducts in a circular bioeconomy
PublicationAnaerobic digestion (AD) is an important biotechnology for treating biodegrad- able residues and producing bioenergy, yet its full potential remains untapped. We investigate a two-phase AD system for biorefinery applications, producing valuable bioproducts, such as volatile fatty acids (VFAs) and biogas, from grass feedstock. We introduce a demand-driven operational approach to match mar- ket conditions, while minimising water...
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Elucidating charge transfer process and enhancing electrochemical performance of laser-induced graphene via surface engineering with sustainable hydrogel membranes: An electrochemist's perspective
PublicationLaser-induced graphene (LIG) has emerged as a promising solvent-free strategy for producing highly porous, 3D graphene structures, particularly for electrochemical applications. However, the unique character of LIG and hydrogel membrane (HM) coated LIG requires accounting for the specific conditions of its charge transfer process. This study investigates electron transfer kinetics and the electroactive surface area of LIG electrodes,...
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Enhanced electrochemical performance of sulfur-doped laser-induced graphene supercapacitors: Synergistic effects of doping and plasmochemical surface modification
PublicationThis work introduces a novel, scalable methodology for rapidly fabricating sulfur-doped laser-induced graphene with enhanced porosity and wetting characteristics, targeting advanced supercapacitor applications. An infrared laser scribing technique was employed to create a three-dimensional porous graphene network, with in-situ sulfur doping achieved through physical evaporation using powder precursor. A second-pass laser process...
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Evaluation of Selected Modulation Techniques in Underwater Multipath Channel
PublicationThere is a growing interest in the use of Autonomous Underwater Vehicles (AUVs) and Underwater Sensor Networks (USNs) for scientific, military, and industrial applications, leading to the development of wireless underwater communications. However, the channel for Underwater Acoustic (UWA) communications is challenging compared to the radio wave propagation in the air. Especially in shallow waters, where the channel has strong multipath...
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Expert system against machine learning approaches as a virtual sensor for ventricular arrhythmia risk level estimation
PublicationRecent advancements in machine learning have opened new avenues for preventing fatal ventricular arrhythmia by accurately measuring and analyzing QT intervals. This paper presents virtual sensor based on an expert system designed to prevent the risk of fatal ventricular arrhythmias associated with QT-prolonging treatments. The expert system categorizes patients into three risk levels based on their electrocardiogram-derived QT...
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Exploration of Behavioral Patterns and Cognitive Biases among Stock Market Investors
PublicationThis study aims to explore behavioral patterns and cognitive biases among stock market investors. By analyzing investor behavior through a stock market simulator, the research seeks to understand the impact of cognitive biases on investment decisions. The methodology encompasses a detailed analysis of transaction data to identify prevalent patterns and biases. Findings suggest that biases such as overconfidence, representativeness...
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Follow-up assessment of the microvascular function in patients with long COVID
PublicationLong COVID is a complex pathophysiological condition. However, accumulating data suggests that COVID-19 is a systemic microvascular endothelial dysfunction with different clinical manifestations. In this study, a microvascular function was assessed in long COVID patients (n = 33) and healthy controls (n = 30) using flow-mediated skin fluorescence technique (FMSF), based on measurements of nicotinamide adenine dinucleotide fluorescence...
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Frequency Reconfigurable PIN Diode-Based Reuleaux-Triangle-Shaped Monopole Antenna for UWB/Ku Band Applications
PublicationThis paper presents a frequency reconfigurable monopole antenna developed for UWB/Ku band applications. The design employs a microstrip-fed Reuleaux-triangle-shaped patch with a defected ground structure. The antenna exhibits a wide operating bandwidth achieved due to rectangular slits integrated into the Reuleaux-triangle patch. Meanwhile, adding rectangular slots in the ground plane improves the return loss level. Frequency reconfigurability...
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Highly Compact Dual-Band Frequency Selective Surface for Path-loss and Coverage Improvement in Millimeter-wave Advanced Wireless Applications
PublicationIn this work, a compact dual-band frequency selective surface (FSS) for path-loss and coverage improvement in advanced wireless communication is showcased. The proposed FSS is a single-layer design with stable and high performance at both 24 GHz and 38 GHz operating frequencies, respectively. The design is highly compact with two wide-band reflection coefficient responses having 49.5% (14.5 – 26.4 GHz) and 66.57% (35.8 – 39.8 GHz)...
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Implementation of Time-Averaged Restraints with UNRES Coarse-Grained Model of Polypeptide Chains
PublicationTime-averaged restraints from nuclear magnetic resonance (NMR) measurements have been implemented in the UNRES coarse-grained model of polypeptide chains in order to develop a tool for data-assisted modeling of the conformational ensembles of multistate proteins, intrinsically disordered proteins (IDPs) and proteins with intrinsically disordered regions (IDRs), many of which are essential in cell biology. A numerically stable variant...
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Implementing an Analytical Model to Elucidate the Impacts of Nanostructure Size and Topology of Morphologically Diverse Zinc Oxide on Gas Sensing
PublicationThe development of state-of-the-art gas sensors based on metal oxide semiconductors (MOS) to monitor hazardous and greenhouse gas (e.g., methane, CH4, and carbon dioxide, CO2) has been significantly advanced. Moreover, the morphological and topographical structures of MOSs have significantly influenced the gas sensors by means of surface catalytic activities. This work examines the impact of morphological and topological networked...
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Isolation Improvement in MIMO Antenna with a Simple Hybrid Technique of Orthogonal and Inverse Currents
PublicationThis paper presents a compact high-isolation multiple-input multiple-output (MIMO) antenna developed using a hybrid approach. The proposed technique combines induced orthogonal currents and self-inverse currents to enhance the antenna's performance. Orthogonal currents are generated by strategically etching open slots on the antenna patches, while self-inverse currents are introduced by integration of annular vias. By carefully...
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Machine learning tools match physician accuracy in multilingual text annotation
PublicationIn the medical field, text annotation involves categorizing clinical and biomedical texts with specific medical categories, enhancing the organization and interpretation of large volumes of unstructured data. This process is crucial for developing tools such as speech recognition systems, which help medical professionals reduce their paperwork. It addresses a significant cause of burnout reported by up to 60% of medical staff....
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Modeling of microstructure evolution during high-temperature oxidation of porous Fe-Cr steels
PublicationResearch on the high-temperature oxidation of metals and alloys is experimentally challenging due to the requirement for long-term corrosion exposure, and in the case of porous alloys, due to their complex internal microstructure. In this study, a corrosion model based on the morphological operations of dilation and erosion has been developed. This approach allows for a utilization of various raster representations of the microstructure...
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Nanotechnology meets radiobiology: Fullerenols and Metallofullerenols as nano-shields in radiotherapy
PublicationDespite significant advances in the development of radioprotective measures, the clinical application of radioprotectors and radiomitigators remains limited due to insufficient efficacy and high toxicity of most agents. Additionally, in oncological radiotherapy, these compounds may interfere with the therapeutic effectiveness. Recent progress in nanotechnology highlights fullerenols (FulOHs) and metallofullerenols (Me@FulOHs) as...
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Noisy (Binary) Searching: Simple, Fast and Correct
PublicationThis work considers the problem of the noisy binary search in a sorted array. The noise is modeled by a parameter p that dictates that a comparison can be incorrect with probability p, independently of other queries. We state two types of upper bounds on the number of queries: the worst-case and expected query complexity scenarios. The bounds improve the ones known to date, i.e., our algorithms require fewer queries. Additionally,...
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Optimizing nature-based solutions for urban flood risk mitigation: A multi-objective genetic algorithm approach in Gdańsk, Poland
PublicationNature-based Solutions (NbS) have emerged as a sustainable approach to managing flood risks by enhancing natural water retention and reducing surface runoff in urban areas. As climate change and rapid urbanization exacerbate flood hazards, optimizing the spatial deployment of NbS is crucial for improving urban resilience and mitigating flood impacts. This study presents a comprehensive optimization framework for the spatial allocation...
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Physicochemical properties of La0.5Ba0.5Co1-xFexO3-δ (0≤x≤1) as positrode for proton ceramic electrochemical cells
PublicationWe report on essential properties of materials in the series La0.5Ba0.5Co1-xFexO3-δ as positrodes for proton ceramic electrochemical cells (PCECs). The unit cell and thermochemical expansion coefficient (TCEC) of these cubic perovskites decrease with iron content x, the TCEC of La0.5Ba0.5FeO3-δ going as low as 11·10-6 1/K. The materials behave as LaMO3 perovskites with small band gaps and Ba acting as acceptors compensated by electron...
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Polymer Materials for U-Shaped Optic Fiber Sensors: A Review
PublicationFiber optic sensors have gained popularity over the last few decades. This is due to their numerous advantages, such as good metrological parameters, biocompatibility and resistance to magnetic and electric fields and environmental pollution. However, those built from glass fiber have one main disadvantage—they are fragile, meaning they can be easily damaged, even by the presence of vibration. Due to the great progress made by...
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Power Transmission for Millimeter-Wave Indoor/Outdoor Wearable IoT Devices Using Grounded Coplanar Waveguide-Fed On-Body Antenna
PublicationThis paper presents for the first-time evaluation of wireless power transmission (WPT) for sustainable low-powered Internet of Things (IoT) devices in realistic indoor/outdoor scenarios using empirical propagation models at 28 GHz. The used empirical propagation models have shown that using an on-body 9×9 mm-wave rectenna array based on a proposed mm-wave antenna is able to charge IoT devices at a distance of 57 m for line-of-sight...
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RCS Enhancement of Millimeter Wave LTCC Van Atta Arrays With 3-D Printed Lenses for Chipless RFID Applications
PublicationIn this paper, we present a new method to enhance the radar- cross section (RCS) of Van Atta arrays which can be used in chipless radio-frequency identification tags operating in millimeter wave frequency bands. Small planar Low-Temperature Co-fired Ceramic (LTCC) Van Atta arrays, that are durable and can operate in harsh environments, are combined with 3-D printed lenses to increase or modify the shape of their RCS by up to 10...
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Room vs. Body Temperature to Evaluate Electrical Interface Parameters of State-Of-The-Art PEDOT : PSS-Based Electrodes
PublicationIn this work, the effect of the simulated body fluid temperature on the electrical interface parameters of the state-of-the-art PEDOT-PSS electrode was studied. PEDOT-PSS was synthesized by electrodeposition on graphite and gold-coated-graphite electrodes. All electrochemical measurements were performed in phosphate-buffered saline aqueous solution (pH 7.4) at room temperature (25 °C) and body temperature (37 °C). The results of...
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Secondary Structure in Free and Assisted Modeling of Proteins with the Coarse-Grained UNRES Force Field
PublicationSecondary structure is a solid scaffold on which the three-dimensional structure of a protein is built. Therefore, care must be taken to reproduce the secondary structure as accurately as possible in the simulations of protein systems. In this chapter, we summarize the physics-based energy terms that govern secondary-structure formation, the auxiliary restraints on secondary structure derived from bioinformatics and from the experimental...
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Strategies for feature-assisted development of topology agnostic planar antennas using variable-fidelity models
PublicationDesign 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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The Impact of 8- and 4-Bit Quantization on the Accuracy and Silicon Area Footprint of Tiny Neural Networks
PublicationIn 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
PublicationThe 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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Two Approaches to Constructing Certified Dominating Sets in Social Networks
PublicationSocial 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
PublicationCancer 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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UNRES web server: Extensions to nucleic acids, prediction of peptide aggregation, and new types of restrained calculations
PublicationThe 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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UV light-activated gas mixture sensing by ink-printed WS2 layer
PublicationWe 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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Wideband High Efficiency Slot Array Antenna Based on Gap Waveguide Single-Layer Feeding Network
PublicationA 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...
Year 2024
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3-D Printable Metal-Dielectric Metasurface for Risley Prism-Based Beam-Steering Antennas
PublicationA 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
Publication3D 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
PublicationA 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
PublicationUltra-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
PublicationThis 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...