Wyniki wyszukiwania dla: underwater%20communications
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Minichannel and minigap classification criteria based on the aspect ratio of the minigeometry: A numerical study
PublikacjaA detailed numerical investigation has been carried out to analyze the diabatic flow distribution and velocity profile in 18 minigeometries with various aspect ratios for V-type and I-type flow configurations (for 36 cases) assuming ethanol as a working fluid. The aim of the study is to distinguish the value of the aspect ratio for which the flow in minigeometry starts to be two-dimensional (minigap). Cases with a constant Reynolds...
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A compact spline-enhanced monopole antenna for broadband/multi-band and beyond UWB applications
PublikacjaIn this work, a compact monopole antenna for broadband/multi-band and beyond ultra- wideband (UWB) communication has been proposed. The structure is based on a spline-enhanced radiator with a broadband feed and a modified ground plane. Rigorous design optimization of the radiator has been performed in a two-stage framework where optimization of the structure with respect to electrical performance is followed by explicit miniaturization...
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A finite element analysis of thermal energy inclination based on ternary hybrid nanoparticles influenced by induced magnetic field
PublikacjaThe use of hybrid nanoparticles to improve thermal processes is a key method that has implications for a variety of interventions utilized in many sectors. This paper aimed to look into the impacts of ternary nanoparticles on hyperbolic tangent materials to establish their thermal characteristics. Flow describing equations have been explored in the presence of heat production, non-Fourier heat flux, and an induced magnetic field....
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Generalization of Kramers-Krönig relations for evaluation of causality in power-law media
PublikacjaClassical Kramers-Krönig (K–K) relations connect real and imaginary parts of the frequency-domain response of a system. The K–K relations also hold between the logarithm of modulus and the argument of the response, e.g. between the attenuation and the phase shift of a solution to a wave-propagation problem. For square-integrable functions of frequency, the satisfaction of classical K–K relations implies causality in the time domain....
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On possible applications of media described by fractional-order models in electromagnetic cloaking
PublikacjaThe purpose of this paper is to open a scientific discussion on possible applications of media described by fractional-order (FO) models (FOMs) in electromagnetic cloaking. A 2-D cloak based on active sources and the surface equivalence theorem is simulated. It employs a medium described by FOM in communication with sources cancelling the scattered field. A perfect electromagnetic active cloak is thereby demonstrated with the use...
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Design-oriented modeling of antenna structures by means of two-level kriging with explicit dimensionality reduction
PublikacjaThe employment of full-wave electromagnetic (EM) analysis is a practical necessity in the design of contemporary antenna structures. This is because simpler models are generally not available or of limited accuracy. At the same time, EM-based design is computationally expensive. Consequently, the ways of accelerating tasks such as parametric optimization or uncertainty quantification have to be sought. A possible workaround that...
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Double-diffusive natural convection energy transfer in magnetically influenced Casson fluid flow in trapezoidal enclosure with fillets
PublikacjaThe prime motive of this disquisition is to deal with mathematical analysis of natural convection energy transport driven by combined buoyancy effects of thermal and solutal diffusion in a trapezoidal enclosure. Casson fluid rheological constitutive model depicting attributes of viscoelastic liquids is envisioned. The influence of the inclined magnetic field governed by Lorentz field law is also considered. To raise the essence...
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High Isolation Metamaterial-based Dual-band MIMO Antenna for 5G Millimeter-wave Applications
PublikacjaThis article presents a high-isolation metamaterial-based dual-band multiple-input multiple-output (MIMO) antenna for 5G millimeter-wave communication networks. The proposed antenna is a pentagon-shaped monopole that provides a dual-band response with a wide operating bandwidth at 5G 28/28 bands. The antenna is printed on 0.508-mm-thick Rogers RT5880 substrate of relative permittivity ɛr =2.2. It exhibits a small physical size...
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Seafloor characterisation using multibeam data: sonar image properties, seabed surface properties and echo properties
PublikacjaIn the paper, the approach to seafloor characterisation is presented. The multibeam sonars, besides their well verified and widely used applications like high resolution bathymetry and underwater object detection and imaging, are also the promising tool in seafloor characterization and classification, having several advantages over conventional single beam echosounders. The proposed approach relies on the combined, concurrent use...
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Methodology for Processing of 3D Multibeam Sonar Big Data for Comparative Navigation
PublikacjaAutonomous navigation is an important task for unmanned vehicles operating both on the surface and underwater. A sophisticated solution for autonomous non-global navigational satellite system navigation is comparative (terrain reference) navigation. We present a method for fast processing of 3D multibeam sonar data to make depth area comparable with depth areas from bathymetric electronic navigational charts as source maps during...
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DATABASE AND BIGDATA PROCESSING SYSTEM FOR ANALYSIS OF AIS MESSAGES IN THE NETBALTIC RESEARCH PROJECT
PublikacjaA specialized database and a software tool for graphical and numerical presentation of maritime measurement results has been designed and implemented as part of the research conducted under the netBaltic project (Internet over the Baltic Sea – the implementation of a multi-system, self-organizing broadband communications network over the sea for enhancing navigation safety through the development of e-navigation services.) The...
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Cost-Efficient EM-Driven Size Reduction of Antenna Structures by Multi-Fidelity Simulation Models
PublikacjaDesign of antenna systems for emerging application areas such as the Internet of Things (IoT), fifth generation wireless communications (5G), or remote sensing, is a challenging endeavor. In addition to meeting stringent performance specifications concerning electrical and field properties, the structure has to maintain small physical dimensions. The latter normally requires searching for trade-off solutions because miniaturization...
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Direct Constraint Control for EM-Based Miniaturization of Microwave Passives
PublikacjaHandling constraints imposed on physical dimensions of microwave circuits has become an important design consideration over the recent years. It is primarily fostered by the needs of emerging application areas such as 5G mobile communications, internet of things, or wearable/implantable devices. The size of conventional passive components is determined by the guided wavelength, and its reduction requires topological modifications,...
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UWB Microstrip Antennas on a Cylindrical Surfaces
PublikacjaConformal antennas are becoming popular due to their many advantages and possibilities of applications they offer. The advantages of using antennas with a curved surface arise not only from the possibility of integrating them with the object on which they are mounted on but also from the increase, relatively to planar antennas, of their visible angular range. The circular antenna arrays, or arrays of radiators located on the surface...
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A Comprehensive Survey on Antennas On-Chip Based on Metamaterial, Metasurface, and Substrate Integrated Waveguide Principles for Millimeter-Waves and Terahertz Integrated Circuits and Systems
PublikacjaAntennas on-chip are a particular type of radiating elements valued for their small footprint. They are most commonly integrated in circuit boards to electromagnetically interface free space, which is necessary for wireless communications. Antennas on-chip radiate and receive electromagnetic (EM) energy as any conventional antennas, but what distinguishes them is their miniaturized size. This means they can be integrated inside...
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A Novel Versatile Decoupling Structure and Expedited Inverse-Model-Based Re-Design Procedure for Compact Single-and Dual-Band MIMO Antennas
PublikacjaMultiple-input multiple-output (MIMO) antennas are considered to be the key components of fifth generation (5G) mobile communications. One of the challenges pertinent to the design of highly integrated MIMO structures is to minimize the mutual coupling among the antenna elements. The latter arises from two sources, the coupling in the free space and the coupling currents propagating on a ground plane. In this paper, an array of...
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Effect of slag coal ash and foamed glass on the mechanical properties of two-stage concrete
PublikacjaTwo-stage concrete (TSC) is known by various names such as colcrete, Polcrete, preplaced aggregate concrete and prepacked concrete. It is different from traditional concrete in two fundamental ways, namely method of construction and mix proportion. Two-stage concrete (TSC) is defined as firstly, coarse aggregates are placed into the formwork and grout is applied to fill in the between coarse aggregate particles voids. Secondly,...
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Improved-Efficacy EM-Based Antenna Miniaturization by Multi-Fidelity Simulations and Objective Function Adaptation
PublikacjaThe growing demands for integration of surface mount design (SMD) antennas into miniatur-ized electronic devices have been continuously imposing limitations on the structure dimen-sions. Examples include embedded antennas in applications such as on-board devices, picosatel-lites, 5G communications, or implantable and wearable devices. The demands for size reduction while ensuring a satisfactory level of the electrical and field...
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Network-aware Data Prefetching Optimization of Computations in a Heterogeneous HPC Framework
PublikacjaRapid development of diverse computer architectures and hardware accelerators caused that designing parallel systems faces new problems resulting from their heterogeneity. Our implementation of a parallel system called KernelHive allows to efficiently run applications in a heterogeneous environment consisting of multiple collections of nodes with different types of computing devices. The execution engine of the system is open for...
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Theory and implementation of a virtualisation level Future Internet defence in depth architecture
PublikacjaAn EU Future Internet Engineering project currently underway in Poland defines three parallel internets (PIs). The emerging IIP system (IIPS, abbreviating the project’s Polish name), has a four-level architecture, with level 2 responsible for creation of virtual resources of the PIs. This paper proposes a three-tier security architecture to address level 2 threats of unauthorised traffic injection and IIPS traffic manipulation...
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Crystal structures of eight- and ten-membered cyclic bisanisylphosphonothioyl disulfanes and comparison with their P-ferrocenyl analogues
PublikacjaTwo new crystal structures of eight- and ten-membered cyclic bisanisylphosphonothioyl disulfanes, namely 2,5-bis(4-methoxyphenyl)-1,6,3,4,25,55- dioxadithiadiphosphocane-2,5-dithione, C16H18O4P2S4, and 2,5-bis(4-methoxyphenyl)-1,6,3,4,25,55-dioxadithiadiphosphecane-2,5-dithione, C18H22O4P2S4, have been determined and compared to structures of the ferrocenyl analogues. The eight-membered rings have similar conformations (TBC) but...
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Dynamic Re-Clustering Leach-Based (Dr-Leach) Protocol for Wireless Sensor Networks
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Crystal structures of (E)-3-(4-hydroxybenzylidene)chroman-4-one and (E)-3-(3-hydroxybenzylidene)-2-phenylchroman-4-one
PublikacjaThe synthesis and crystal structures of (E)-3-(4-hydroxybenzylidene)chroman-4-one, C16H12O3,I, and (E)-3-(3-hydroxybenzylidene)-2-phenylchroman-4-one,C22H16O3,II, are reported. These compounds are of interest with respect to biological activity. Both structures display intermolecular C—H---O and O—H---O hydrogen bonding, forming layers in the crystal lattice. The crystal structure of compound I is consolidated...
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Hydrological indicators of water zones in inundation, historical water levels, and forcing data for the 1881-2099 period in the lower Biebrza valley
Dane BadawczeThis data set contains hydrological (1) indicators of water source extents in the Biebrza River floodplain (NE Poland) simulated using an integrated hydrological model (IHM), (2) forcing data for the IHM, and (3) water levels in the Osowiec station from the period 1881-1910.
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Model zaangażowania w relacji usługodawca-klient
PublikacjaW niniejszej monografii przedstawiono rozwiązania pozwalające lepiej zrozumieć złożoność relacji występujących pomiędzy usługodawcami a klientami oraz metody, które pozwalają tę wiedzę wykorzystać w doskonaleniu procesów organizacji usługowych. Monografia podejmuje problem kształtowania zaangażowania na styku usługodawca–klient jako wstępnego i koniecznego warunku rozwijania relacji w usługach. Opierając się na klasycznej drabinie...
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(2,2'-Bipyridine)bis(tri-tert-butoxysilanethiolato-kS)lead(II) and (4,7-diphenyl-1,10-phenanthroline-k2N,N')bis(tri-tert-butoxysilanethiolato-kS)lead(II) benzene hemisolvate
PublikacjaWyznaczono i opisano struktury rentgenowskie tytułowych związków. Atom ołowiu w obu przypadkach wykazuje koordynację typu zniekształconej piramidy kwadratowej o rdzeniu PbON2S2 w której jeden z atomów siarki leży w pozycji osiowej. Struktury są stabilizowane przez oddziaływania międzycząsteczkowe typu pi-pi oraz C-H...pi.
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Supramolecular structures of bis-thionooxalamic acid esters derived from (±)-cyclohexane-1,2-diamine and (±)-1,2-diphenylethylenediamine
PublikacjaZsyntezowano dwa racemiczne estry kwasu bis(tiooksamowego) i zbadano ich sposób upakowania w sieci krystalicznej. Analiza rentgenograficzna monokryształów badanych związków wykazała, że organizują się one w jednowymiarowe struktury, które tworzone są przez molekuły o przeciwnej chiralności, połączone za pomocą trójcentrowych wiązań wodorowych C=S...NH...O=C. Powstające agregaty są dodatkowo stabilizowane przez słabe oddziaływania...
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A study of chirality in bis(1,2-dimethoxyethane-κ^2 O,O')sodium bis(tri-tert-butoxysilanethiolato-κ2O,S)sodate
PublikacjaPraca prezentuje analizę samoorganizacji związku kompleksowego z prostszych jonów na przykładzie silanotiolanosodanu bis(dimetoksyetan)sodu. Stwierdzono, że w anionie (RS)2Na- obie grupy tri-tert-butoksysilanotiolanowe mają tę samą skręcalność - obie (P) lub obie (M). Zjawisko to występuje we wszystkich znanych sodanach i litanach zawierających grupę (tert-BuO)3SiS.
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10-Methyl- and 9,10-dimethyl acridinium methyl sulfate
PublikacjaThe title compounds, C(14)H(12)N(+).CH(3)O(4)S(-), (I), and C(15)H(14)N(+).CH(3)O(4)S(-), (II), respectively, crystallize with the planar 10-methylacridinium or 9,10-dimethylacridinium cations arranged in layers, parallel to the twofold axis in (I) and perpendicular to the 2(1) axis in (II). Adjacent cations in both compounds are packed in a 'head-to-tail' manner. The methyl sulfate anion only exhibits planar symmetry in (II)....
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9-Cyano-10-methylacridinium hydrogen dinitrate
PublikacjaThe title compound, C15H11N2+·HN2O6−, crystallizes in the monoclinic space group C2/c with four molecules in the unit cell. The planar 9-cyano-10-methylacridinium cations lie on crystallographic twofold axes and are arranged in layers, almost perpendicular to the ac plane, in such a way that neighbouring molecules are positioned in a `head-to-tail' manner. These cations and the hydrogen dinitrate anions are linked through C—H⋯O...
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9-(Trichloroacetylimino)acridine monohydrate
PublikacjaThe title compound, alternatively called N-acridin-9(10H)-ylidene-2,2,2-trichloroacetamide monohydrate, C15H9Cl3N2O·H2O, crystallizes in space group P21/c with Z = 4. The acridine moieties are arranged in layers, tilted at an angle of 15.20 (4)° relative to the ac plane, while adjacent molecules pack in a head-to-tail manner. Acridine and water molecules form columns along the b axis held in place by a network of hydrogen...
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Tetraethylammonium bis(N,N-diethyldithiocarbamato-k2S,S')iodocadmate(II)
PublikacjaW ramach prezentowanej pracy otrzymano bis-(N,N-dietyloditiokarbaminiano-2S,S')jodokadmian tetraetyloamoniowy, krystalizujący w układzie rombowym, w grupie przestrzennej Pnma. Związek ten posiada kompleksowy anion [Cd(S2NEt2)2I]-, w którym do centralnego atomu Cd przykoordynowane są dwa kleszczowe ligandy ditiokarbaminianowe oraz atom jodu. Centralny rdzeń tego związku, w odróżnieniu od innych układów typu [Cd(dtc)X], posiada...
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Bis(diisopropylammonium) thiosulfate and bis(tert-butylammonium) thiosulfate
PublikacjaTwo new dialkylammonium thiosulfates, namely bis(diisopropylammonium) thiosulfate, 2C6H16N+S2O3 2-, (I), and bis(tert-butylammonium) thiosulfate, 2C4H12N+S2O3 2-, (II), have been characterized. The secondary ammonium salt (I) crystallizes with Z = 4, while the primary ammonium salt (II), with more...
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The 2:1 cocrystal of benzamide and pentafluororbenzoic acid
PublikacjaKrystaliczna struktura centrosymetrycznej supermolekuły składa się z czterech cząsteczek benzamidu oraz dwóch kwasu karboksylowego, które powiązane są ze sobą za pomocą wiązań wodorowych typu O-H...O oraz N-H...O.
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The first compound with an unusual type of anion, [Li(SR)2]-:bis(µ2-aqua-d2)tetrakis(aqua-d2)]dilithium(I)bis[bis(tri-tert-butoxysilanethiolato-k2O,S)lithate(I)]dihydrate-d2
PublikacjaTytułowy związek [Li2(D2O)6][Li(C9H27SSiO3)2]2*2D2O, jest pierwszym związkiem z wiązaniem S-M (M-metal alkaliczny), zawierającym niespotykany typ anionu litanowego: [Li(SR)2]-,gdzie R=Si{OC{CH3)3}3. Centrum symetrii związku znajduję się pośrodku pierścienia Li2O2 wchodzącego w skład kationu. Wszystkie atomy litu budujące rdzenie kationów - LiO4 i anionów - LiO2S2, są czterokoordynacyjne. Jednoujemne aniony [Li(SR)2]- są dobrze...
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Two pseudopolymorphs of licl trimers with semicubane structures
PublikacjaCząsteczki tytułowych związków w ciele stałym przyjmują strukturę semikubanów - jest to pierwsza tego typu struktura dla solwatowanego chlorku litu. Jej budowę można opisać jako kuban [Li4Cl4(OPEt3)4], w którym jedna z cząsteczek LiCl została usunięta. Brak tej cząsteczki, a dokładniej mostkującego atomu Li, powoduje deformację struktury kubanu. Naroża zdeformowanego kubanu stanowią trzy atomy litu pochodzące z LiCl oraz cztery...
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Two isomorphic ZnII/CoII complexes with tri-tert-butoxysilanethiol and histamine, and (4-hydroxymethyl-1H-imidazole-κN)bis(tri-tert-butoxysilanethiolato-κ2O,S)zinc(II)
PublikacjaOtrzymano dwa izomorficzne kompleksy cynku(II) i kobaltu(II) z tri-tert-butoksysilanotiolem i histaminą oraz kompleks cynku(II) z tri-tert-butoksysilanotiolem i 4(5)-hydroksymetyloimidazolem. Scharakteryzowano strukturę otrzymanych kompleksów w ciele stałym.
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Influence of chloroform on crystalline products yielded in reactions of 5,10,15,20-tetraphenylporphyrin with HCl and copper(II) salts
PublikacjaStwierdzono, że chloroform wbudowuje się do sieci krystalicznej dichlorowodorku 5,10,15,20-tetrafenyloporfiryny, oraz że powoduje krystalizację nowej, jednoskośnej odmiany polimorficznej porfirynianu miedzi(II), CuTPP. W pracy opisano strukturę krystaliczną solwatu dichlorowodorku porfiryny z ośmioma cząsteczkami chloroformu, C44H32N42+·2Cl-·8CHCl3, i porównano ją...
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(Di-tert-butylmethylphosphane)(η2-di-tert-butylphosphanylphosphinidene)(triphenylphosphane)platinum(0)
PublikacjaStruktura krystaliczna tytułowego związku, [(Ph3P)(tBu2PMe)Pt(η2-tBu2PP)], zawiera cztery cząsteczki w części niezależnej nieznacznie różniące się konformacjami. Odległości P-P w ligandzie tBu2PP są zbliżone dla wszystkich czterech cząsteczek [2.0661(13)-2.0678(13)A˚]. Odległości te, wskazują na wielokrotny charakter wiązania P-P w ligandzie tBu2PP. Atom platyny w kompleksie wykazuje koordynację płaską kwadratową. Prezentowana...
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Structure of EstA esterase from psychrotrophic Pseudoalteromonas sp. 643A covalently inhibited by monoethylphosphonate.
PublikacjaThe crystal structure of the esterase EstA from the cold-adapted bacteriumPseudoalteromonas sp. 643A was determined in a covalently inhibited form at aresolution of 1.35 A˚. The enzyme has a typical SGNH hydrolase structureconsisting of a single domain containing a five-stranded beta-sheet, with threehelices at the convex side and two helices at the concave side of the sheet, and isornamented with a couple of very short helices...
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COPCAMS Kamery umożliwiające kontekstowe rozumienie pozyskiwanego obrazu
ProjektyProjekt realizowany w Wydział Elektroniki, Telekomunikacji i Informatyki zgodnie z porozumieniem 332913 z dnia 2013-11-25
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Influence of intermixing at the Ta/CoFeB interface on spin Hall angle in Ta/CoFeB/MgO heterostructures
PublikacjaWhen a current is passed through a non-magnetic metal with strong spin-orbit coupling, an orthogonal spin current is generated. This spin current can be used to switch the magnetization of an adjacent ferromagnetic layer or drive its magnetization into continuous precession. The interface, which is not necessarily sharp, and the crystallographic structure of the nonmagnetic metal can both affect the strength of current-induced...
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Justyna Zander dr inż.
Osoby -
BEYOND5 Budowa europejskiego łańcucha dostaw dla RFSOI, umożliwiającego tworzenie nowych aplikacji bezprzewodowych do detekcji, komunikacji, komunikacji 5G i przyszłych technologii radiowych
ProjektyProjekt realizowany w Katedra Inżynierii Mikrofalowej i Antenowej zgodnie z porozumieniem 876124 z dnia 2020-05-28