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Shielded HMSIW-Based Self-Triplexing Antenna With High Isolation for WiFi/WLAN/ISM Band
PublikacjaThis article presents a novel design of a miniaturized self-triplexing antenna (STA) based on the shielded half-mode substrate integrated waveguide (S-HMSIW) for WiFi/WLAN/ISM-band applications. The S-HMSIW is constructed by assembling one row of vias and an open slot at the open-ended side of the conventional HMSIW. This configuration increases the quality factor and minimizes unwanted radiation loss, which allows for achieving...
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Analiza zmiennych objaśniających i rozbudowa modelu wyboru środka transportu
PublikacjaW artykule poddano analizie potrzebę uwzględnienia dodatkowych czynników wpływających na wybór środka transportu w prognozowaniu podróży. Przedstawiono dotychczasowe badania wpływu wybranych czynników na podział zadań przewozowych. W oparciu o wyniki krajowych Kompleksowych Badań Ruchu zostały wykonane analizy zależności udziału podróży transportem zbiorowym w obszarach zurbanizowanych od wybranych czynników zewnętrznych.
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Estimation of the effectiveness of nbpt for limiting ammonia emission from urea based on the field experiments
PublikacjaThe efectiveness of the ammonia emission reduction from NBPT-stabilized urea was investigating in 2011 during a field experiment on a grassland plot fertilized with a one-time dose of 60 kgN/ha. The obtained reduction coefficient of ammonia emission equaled 73% and 39-51% relative to erea without the inhibitor and ammonium nitrate, respectively.
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Closed-Loop Control System Design for Wireless Charging of Low-Voltage EV Batteries with Time-Delay Constraints
PublikacjaThis paper presents an inductive power transfer system on the basis of a double single- phase three-level T-type inverter and two split transmitting coils for constant current and constant voltage wireless charging of low-voltage light electric vehicle batteries with closed-loop control, considering time-delay communication constraints. An optimal control structure and a modified control strategy were chosen and implemented to...
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A distributed system for conducting chess games in parallel
PublikacjaThis paper proposes a distributed and scalable cloud based system designed to play chess games in parallel. Games can be played between chess engines alone or between clusters created by combined chess engines. The system has a built-in mechanism that compares engines, based on Elo ranking which finally presents the strength of each tested approach. If an approach needs more computational power, the design of the system allows...
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Software Implementation of the RAKE receiver
PublikacjaThis paper presents concept of the RAKE receiver method with implemented algorithm of shifted phase WMSA filter (Weighed Multi-Slot Averaging). First, the RAKE receiver block diagram and WMSA filter analysis have been described. Next, the results of the simulation have been described. In summary usefulness of the concept has been confirmed.
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Mode choice modelling for urban areas
PublikacjaThe article presents the question of mode choice modelling in a four-stage travel modelling process. The article indicates limitations of currently used simplified methods of mode choice modelling and presents the possibility of using a more detailed approach that accounts for additional, statistically significant factors with the use of advanced mathematical tools, discrete choice models. A need has also been identified to include...
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NP-completeness of convex and weakly convex domiating set decision problems.
PublikacjaLiczby dominowania wypukłego i słabo wypukłego są nowymi rodzajami liczb dominowania. W tym artykule pokazujemy, że problemy decyzyjne dominowania wypukłegi i słabo wypukłego są NP-zupełne w przypadku grafów dwudzielnych oraz split grafów. Posługując się zmodyfikowanym algorytmem Washalla możemy w czasie wielomianowym określić, czy dany podzbiór wierzchołków grafu jest spójny bądź słabo spójny.
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A Simple-Topology Compact Broadband Circularly Polarized Antenna With Unidirectional Radiation Pattern
PublikacjaIn this letter, a geometrically simple, reflector-backed single-point-fed circularly polarized (CP) antenna with unidirectional radiation pattern is presented. The structure comprises a simple coplanar waveguide (CPW) feeding circuit with an open slot etched on one side of the coplanar ground. The enhanced CP bandwidth is obtained by combining the loop mode, the slot mode, and the asymmetrical configuration of the coplanar ground...
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On Alternative Approaches to Design of Corporate Feeds for Low-Sidelobe Microstrip Linear Arrays
PublikacjaTwo design approaches, illustrated by simulations and measurements, aiming at a systematic computer-aided design of printed circuit feeds for low-sidelobe microstrip antenna arrays are described. The novelty of these approaches resides in identification of the optimal feed architectures with subsequent simulation-based optimization of the feed and array aperture dimensions. In this work, we consider microstrip corporate feeds realizing...
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Effects of the Covid-19 travel restrictions on metropolises mobility: empirical evidence from the Tricity metropolis (Poland)
PublikacjaThis paper aims to assess changes in mobility and modal shift caused by COVID-19 travel restrictions among the residents of Gdańsk Bay Metropolis (Poland). Measurement’s moments were assumed in periods differing in the level of restric- tions. The computer-assisted telephone interview (CATI) was carried out in November and December 2020. The results did not confirm the expected modal shift. However, significant changes in the number...
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On Rapid Design Optimization and Calibration of Microwave Sensors Based on Equivalent Complementary Resonators for High Sensitivity and Low Fabrication Tolerance
PublikacjaThis paper presents the design, optimization, and calibration of multivariable resonators for mi-crowave dielectric sensors. An optimization technique for circular complementary split ring reso-nator (CC-SRR) and square complementary split ring resonator (SC-SRR) is presented to achieve the required transmission response in a precise manner. The optimized resonators are manufac-tured using a standard photolithographic technique...
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Low-Cost Surrogate Modeling of Miniaturized Microwave Components Using Nested Kriging
PublikacjaIn the paper, a recently reported nested kriging methodology is employed for modeling of miniaturized microwave components. The approach is based on identifying the parameter space region that contains high-quality designs, and, subsequently, rendering the surrogate in this subset. The results obtained for a miniaturized unequal-power-split rat-race coupler and a compact three-section impedance transformer demonstrate reliability...
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The prns butterfly synthesis in the FPGA
Publikacjaw pracy przedstawiono sprzętową implementację elementarnych obliczeń, określanych jako obliczenia motylkowe, dla splotu realizowanego z użyciem wielomianowego systemu resztowego(ang. polynomial residue number system - prns). obliczenia są wykonywane z zastosowaniem reprezentacji systemu diminished-1. opisano syntezę układu realizującego obliczenie motylkowe w środowisku xilinx w układzie virtex 4. podano również wymaganą ilość...
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Ograniczone (p1, p2,...,pk) kolorowanie wierzchołków grafów.
PublikacjaProblem ograniczonego (p1,...,pk) kolorowania grafów polega na poszukiwaniu odpowiedzi na pytanie, czy istnieje takie pokolorowanie wierzchołków grafu , że krotności użycia poszczególnych barw są równe ustalonym progom p1,...,pk. W ogólnym przypadku problem ten, jako uogólnienie klasycznego kolorowania grafów pozostaje NP-zupełnym. W pracy przedstawiamy wyniki dotyczące ograniczonego kolorowania split grafów, kografów oraz...
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Dynamic fracture of brittle shells in a space-time adaptive isogeometric phase field framework
PublikacjaPhase field models for fracture prediction gained popularity as the formulation does not require the specification of ad-hoc criteria and no discontinuities are inserted in the body. This work focuses on dynamic crack evolution of brittle shell structures considering large deformations. The energy contributions from in-plane and out-of-plane deformations are separately split into tensile and compressive components and the resulting...
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Autonomous Battery Drive in Trolleybuses: an Overview of Practical Examples
PublikacjaBattery electric buses are believed to be means of transportation of the future. However, despite the continuous development of electrochemical batteries technology and the multitude of electric buses on offer, it is still no proved solutions that can be widely used. Charging is the one of the weakness point of the electric buses. Trolleybuses are alternative for them. Especially, trolleybuses equipment with traction batteries...
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Właściwości sterowników przetwornic dc-dc opartych na algorytmach splotowych
PublikacjaW pracy przedstawiono wybrane problemy projektowania cyfrowych sterowników przetwornic impulsowych. Szczególny nacisk położono na syntezę umożliwiającą implementację sprzętową kontrolerów w oparciu o tanie technologie CMOS charakteryzujące się znacznymi ograniczeniami na szybkość działania bloków funkcjonalnych. Zaprezentowano symulacje porównawcze właściwości klasycznych korektorów cyfrowych uzyskanych na podstawie prototypu analogowego...
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Magnetic field microsensor based on GaAs MESFET
PublikacjaA novel concept of the drain separation design in a horizontally-split-drain GaAs MAGFET sensor, based on epitaxial layer growth, was developed. Proper choice of GaAs/AlAs/GaAs epitaxial layer sequence provided good electrical isolation between the drain regions. The measured leakage current between the drain regions was in the range of nA for up to 2V drain voltage bias difference. Performed analytical and numerical calculations...
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ANYTIME POLYNOMIAL HEURISTIC ALGORITHM FOR PARTITIONING GROUPS OF DATA WITH PRESERVING CLASS PROPORTIONS FOR CROSS-VALIDATION
PublikacjaThe article describes a problem of splitting data for k-fold cross-validation, where class proportions must be preserved, with additional constraint that data is divided into groups that cannot be split into different cross-validation sets. This problem often occurs in e.g. medical data processing, where data samples from one patient must be included in the same cross-validation set. As this problem is NP-complete, a heuristic...
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A Geometrically Simple Compact Wideband Circularly Polarized Antenna
PublikacjaA compact broadband wide-slot circular polarization (CP) antenna is proposed. An inverted L-shape parasitic strip at the open end of a microstrip line extension and a slot modification is applied to attain wideband CP. The advantage of this technique is simplicity which makes it readily re-designable for different frequency bands. To demonstrate the concept, three designs working at different frequencies are obtained. The redesign...
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A graphical approach to yield and boundary surfaces of selected hypoplastic constitutive equations
PublikacjaThe article describes how to identify the boundary and yield surface for hypoplastic constitutive equations proposed by Wu, Gudehus and Bauer. It is shown how to identify and plot the surfaces for any equation in this class. Calculation errors are analyzed characteristic for appleid set of numerical formulas. In the paper there are computer links to the source code prepared in the MATLAB system, based on istructions in the article....
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Adaptive acoustic crosstalk cancellation in mobile computer device
PublikacjaThe cancellation of acoustic crosstalk is employed to enhance the stereo image in mobile listening conditions. A practical setup employing a mobile computer is employed. The adaptation of the crosstalk cancellation filter to the position of the listener's head is featured. The measurement evaluating the possibility of practical application of the method are described. The head and torso simulator was used for measurements. The...
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Expedited two-objective dimension scaling of compact microwave passives using surrogate models
PublikacjaGeometry scaling of compact microwave structures is a challenging problem because of complex relationships between the physical dimensions and electrical characteristics, mostly caused by considerable cross-couplings in densely arranged layouts. Here, a procedure for expedited dimension scaling of compact microwave couplers with respect to two independent criteria has been presented. Our approach involves inverse surrogate models...
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Analyzing the Impact of Simulated Multispectral Images on Water Classification Accuracy by Means of Spectral Characteristics
PublikacjaRemote sensing is widely applied in examining the parameters of the state and quality of water. Spectral characteristics of water are strictly connected with the dispersion of electromagnetic radiation by suspended matter and the absorp-tion of radiation by water and chlorophyll a and b.Multispectral sensor ALI has bands within the ranges of electromagnetic radia-tion: blue and infrared, absent in sensors such as Landsat, SPOT,...
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On Computing Curlicues Generated by Circle Homeomorphisms
PublikacjaThe dataset entitled Computing dynamical curlicues contains values of consecutive points on a curlicue generated, respectively, by rotation on the circle by different angles, the Arnold circle map (with various parameter values) and an exemplary sequence as well as corresponding diameters and Birkhoff averages of these curves. We additionally provide source codes of the Matlab programs which can be used to generate and plot the...
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Modified SPWM Technique with Zero-Sequence Voltage Injection for a Five-Phase, Three-Level NPC Inverter
PublikacjaThis article presents a modified sinusoidal pulse-width modulation (SPWM) scheme for a five-phase, three-level neutral-point-clamped inverter. The modulation scheme deploys a modified min–max function to inject the zero-sequence components into the reference modulating signals; hence enabling the effective utilization of the DC-link voltage. Balanced split-input DC-link voltages were achieved through further incorporation of adjustable...
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Analyzing sets of phylogenetic trees using metrics
PublikacjaThe reconstruction of evolutionary trees is one of the primary objectives in phylogenetics. Such a tree represents historical evolutionary relationships between different species or organisms. Tree comparisons are used for multiple purposes, from unveiling the history of species to deciphering evolutionary associations among organisms and geographical areas. In this paper, we describe a general method for comparing phylogenetictrees...
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Using different types of capillary columns as denudation traps: a comparision of sorption properties
PublikacjaOpisano badania odcinków kapilarnych kolumn chromatograficznych (WCOT, SCOT,PLOT) jako pułapek denudacyjnych do ilościowego zatrzymywania śladowych ilości lotnych związków organicznych ze strumienia powietrza. W trakcie badań modelowych (z wykorzystaniem gazowych mieszanin wzorcowych) określono wartości współczynników podziału benzenu, toluenu, etylobenzenu, o-ksylenu i chlorobenzenu (Kfs). Stwierdzono, że grubość filmu fazy stacjonarnej...
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Price Changes in Wholesale Market of Electrical Energy in Poland
PublikacjaThe article discusses the Price changes on the wholesale electricity market in Poland Moreover, The price levels on the futures electricity markets and the spot transactions market are presented. The impact of emission charges under the EU ETS on the price of electricity in the domestic market has been taken into consideration Furthermore, the basic determinants of the generation structure in Poland that influence the level of...
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ANALIZA FUNKCJONOWANIA POLSKIEGO RYNKU ENERGII ELEKTRYCZNEJ W OKRESIE WPROWADZENIA STOPNI ZASILANIA W 2015 ROKU
PublikacjaW artykule przedstawiono opis sytuacji, która doprowadziła do wprowadzenia wysokich stopni zasilania w KSE w sierpniu 2015 r. Omówiono przyczyny i konsekwencje wprowadzenia stopni zasilania, na podstawie analizy zapotrzebowania na moc w KSE. Przedstawiono analizę cen i obrotów na Rynku Bilansującym w tym okresie. Opisano wpływ nietypowej sytuacji na Giełdę Energii oraz na ceny na rynku „spotowym” i rynkach terminowych.
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Shape-controllable synthesis of GdVO4 photocatalysts and their tunable properties in photocatalytic hydrogen generation
PublikacjaNovel visible light responsive materials for water splitting are essential for the efficient conversion of solar energy into hydrogen bond energy. Among other semiconductors, gadolinium orthovanadate has appropriate conduction and valence band edges positioned to split water molecules and a narrow band gap that allows the use of visible light for hydrogen generation. Thus, we present here that hydrogen evolution under visible light...
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INFLUENCE OF TIME ON THE BEARING CAPACITY OF PRECAST PILES
PublikacjaOne of the most popular types of foundations in layered subsoil with very differentiated soil shear strengths are precast piles. One of the reasons is a fact that we can well control the driving process during the installation of these piles. The principles of the assessment of bearing capacity and settlements of the piles given by Eurocode 7, concentrate on two main methods, i.e. Static Pile Load Tests (SPLT) and Dynamic Driving...
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N-phosphonomethylglycine utilization by the psychrotolerant yeast Solicoccozyma terricola M 3.1.4.
PublikacjaSolicoccozymaterricolaM 3.1.4., the yeast strain isolated from soil sample from blueberry cultivation in MiedzyrzecPodlaski in Poland, is capable to split of phosphorus to nitrogen and nitrogen to carbon bonds inN-phosphono-methylglycine (PMG, glyphosate). The biodegradation process proceeds in the phosphate-independent manner. Itis the first example of a psychrotolerant yeast strain able to degrade PMGviaCeN bond cleavage accompanied...
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Near Field Coupled Wireless Microwave Sensor
PublikacjaThis paper presents a wireless planar microwave sensor operating at industrial scientific and medical (ISM) frequency for the detection of dielectric materials. The microwave sensor consists of a reader (ground defected microstrip coupled line) and a passive tag where a complementary split-ring resonator (CSRR) is made on the commercially available copper-foil. The CSRR is a peel-off type tag that is excited using the near field...
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A Compact and Lightweight Microwave Tilt Sensor Based on an SRR-Loaded Microstrip Line
PublikacjaIn this paper, the symmetry property of split ring resonators (SRRs) is exploited to develop a tilt sensor. The sensor is composed of an SRR-loaded microstrip line operating at microwave frequencies. It is shown that the depth of notch in the reflection characteristic of the microstrip is a function of the tilt angle of the SRR. Thus, it can be used for sensing inclination. The sensor benefits from very compact size and light weight....
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Towards Emotion Acquisition in IT Usability Evaluation Context
PublikacjaThe paper concerns extension of IT usability studies with automatic analysis of the emotional state of a user. Affect recognition methods and emotion representation models are reviewed and evaluated for applicability in usability testing procedures. Accuracy of emotion recognition, susceptibility to disturbances, independence on human will and interference with usability testing procedures are...
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Design of compact self-quintuplexing antenna with high-isolation for penta-band applications
PublikacjaThis article presents a novel compact self-quintuplexing antenna architecture based on a substrate-integrated rectangular cavity (SIRC) for pentaband applications. The proposed self-quintuplexing antenna is constructed by employing an SIRC, one Pi-shaped slot (PSS), one T-shaped slot (TSS), and five 50Ω microstrip feedlines. The PSS and TSS are engraved on the top of the SIRC to create five radiating patches, which are excited...
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Broad Stopband, Low-Loss, and Ultra-Compact Dual-Mode Bandpass Filter Based on HMSIRC
PublikacjaIn this investigation, an ultra-compact dual-mode bandpass filter (BPF) with a wide stopband re-sponse is realized by using a half-mode substrate-integrated rectangular cavity (HMSIRC). The HMSIRC resonator is designed with a cavity that is rectangular in shape and has metallic vias along three of the sides. The fourth side is open-ended and contains microstrip feed lines. For the purpose of constructing a magnetic wall, a rectangular...
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Highly-Miniaturized Dual-Mode Bandpass Filter Based on Quarter-Mode Substrate Integrated Waveguide with Wide Stopband
PublikacjaThis paper presents a novel design of a highly-miniaturized dual-mode bandpass filter (BPF) employing a quarter-mode substrate integrated waveguide (QMSIW). The QMSIW resonator is based on a square cavity with metallic vias along two sides, and open-ended edges at the remaining sides that contain orthogonal feed lines. An open slot is introduced along the two sides of the square cavity with metallic vias to form a magnetic wall....
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System Loss in UWB Off-Body Communications in a Ferry Environment
PublikacjaIn this paper, the system loss in UWB off-body communications in a ferry environment based on measurements is presented. A mobile measurement set-up, consisting of WBAN nodes with UWB DWM1000 modules, was used. System loss was split into LOS and NLOS conditions. For the former, the smallest mean value, 24.4 dB, was obtained for the user approaching the fixed terminal, with the antenna on his chest, and the largest, 28.1 dB, for...
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Novel Low-Loss Substrates for 5G Applications
PublikacjaThis paper presents a feasibility study of a new type of microwave low-loss dielectric substrates for 5G network applications. The new substrate materials are composites of polypropylene and high-dielectric-constant micro-ceramics. This combination is expected to form a very low-loss dielectric material at low fabrication cost. Two substrate samples with different dielectric properties are fabricated and their characteristics at...
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Technology-Enhanced Environmental Learning: Co-design of Educational Mobile Application Case
PublikacjaThe process of co-creating an educational mobile application to support environmentally friendly behavior is presented in this paper. The research material consisted of quantitative data collected on the application during the first testing phase by early adopters. The results suggest that the most frequently used features of the app were related to transport and educational activities. While women tended to split their time between...
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Zachowania starszych klientów na rynku usług on-line
PublikacjaOsoby starsze stanowić będą w przyszłości stale zwiększający się rynek konsumencki. Jednocześnie stale rośnie rynek usług online. Dlatego problem korzystania osób starszych z usług on-line nabiera szczególnego znaczenia. W artykule przedstawione zostały wyniki badania sposobu korzystania z usługi pośrednictwa pracy w serwisach internetowych, uzyskane z wykorzystaniem badań okulograficznych - nagrań Gaze Plot oraz wywiadów ThinkAloud....
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Pin-on-Substrate Gap Waveguide: An Extremely Low-Cost Realization of High-Performance Gap Waveguide Components
PublikacjaConsidering the limitations of currently available technologies for the realization of microwave components and antennas, a trade-off between different factors including the efficiency and fabrication cost is required. The main objective of this letter is to propose a novel method for the realization of gap waveguides (GWGs) that take advantage of conventional PCB fabrication technology, thus are low cost and light weight. Moreover,...
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A structure and design of a novel compact UWB MIMO antenna
PublikacjaIn the paper, a concept and design procedure of a novel compact MIMO slot antenna is presented. In order to achieve a better filling of available space, individual antennas are constrained to a triangular shape and optimized for a reduced size. The MIMO structure is then assembled using the two of previously designed antennas in orthogonal arrangement. Surrogate-assisted numerical optimization involving variable-fidelity electromagnetic...
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Geometryczne elementy węzłów
PublikacjaW opracowaniu Geometryczne elementy węzłów opisano takie zagadnienia jak: podział węzła na elementy, drogi główne w obszarze węzła, zasady geometrycznego kształtowania zjazdów i wyjazdów na drogę główną (zjazdy z drogi głównej, wjazdy na drogę główną, lokalizacja wjazdów i zjazdów), zasady geometrycznego kształtowania łącznic (prędkość projektowa łącznic, przekroje poprzeczne dróg łącznikowych, formy geometryczne łącznic, pasy...
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Design of Microwave Lossy Filter Based on Substrate Integrated Waveguide (SIW)
PublikacjaIn this letter, we propose a lossy three-pole Chebyshev filter centered at 5.15 GHz, based on the substrate integrated waveguide (SIW) with scattering characteristics shifted down by 5.68 dB. The filter is composed of three directly coupled SIW cavities with three lossy couplings between nonadjacent resonators. These additional couplings are realized using mixed coupled slot and microstrip lines connected with metal electrode leadless...
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A Dual-Polarized 39 GHz 4x4 Microstrip Antenna Array for 5G MU-MIMO Airflight Cabin Connectivity
PublikacjaThis paper presents the design, fabrication, and experimental validation of a 39 GHz dual-polarized 4x4 microstrip antenna array. The array consists of 16 slot coupled circular microstrip patches, fed through SMPS connectors. The procedure requiring a reduced number of cables for measurement of the uniformly excited antenna array is also presented. The array exhibits 18 dBi peak gain and 2.9 GHz reflection bandwidth and is intended...
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Fatigue strength determination of ship structural joints. Part I - Analytical methods for determining fatigue strength of ship tructures
PublikacjaSpectacular accidents at sea which have happened for a few last years show that hull structures of contemporary sea-going ships are not perfect and must be systematically improved. Fatigue strength is one of the groups of strength problems which affect design of contemporary ship's structures and greatly contribute in their improvement process. In this paper several approaches to estimation of fatigue life of hull structural...