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Tailoring optical constants of few-layer black phosphorus coatings: Spectroscopic ellipsometry approach supported by ab-initio simulation
Publication2D black phosphorus (BP) has attracted extensive attention as an anisotropic platform for novel optoelectronic and polarizing optics applications. Insight into the factors that tune the optical and polarizing properties of 2D BP reveals their essential influence on BP-based photonic and optoelectronic devices. In this work, studies of the optical constants of few-layer black phosphorus coatings are studied and discussed, with particular...
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Integrated Control in High-Speed Networks Using Constrained Model Predictive Control
PublicationThis paper studies congestion control in high-speed communication networks using Model Predictive Control (MPC). Network traffic is assumed to consist of best-effort and priority traffic sources. An integrated controller consisting of two control parts is designed. The controller calculates the capacity for priority sources and the input rate of best-effort sources. MPC is desirable as it can take into account the constraints on...
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A Selection of Starting Points for Iterative Position Estimation Algorithms Using Feedforward Neural Networks
PublicationThis 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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Connectivity in Multi-Interface Networks
PublicationRozważano zagadnienie minimalizacji energii w sieciach bezprzewodowych bez infrastruktury, w których niektóre węzły są wyposażone w więcej, niż jeden interfejs. W przyjętym modelu sieci podano nowe algorytmy przybliżone oraz wyniki dotyczące złożoności obliczeniowej dla problemu najtańszej spójnej podsieci spinającej.
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Scanning networks with cactus topology
PublicationThe family of Pursuit and Evasion problems is widelystudied because of its numerous practical applications,ranging from communication protocols to cybernetic andphysical security. Calculating the search number of a graphis one of most commonly analyzed members of this problemfamily. The search number is the smallest number of mobileagents required to capture an invisible and arbitrarily fastfugitive, for instance piece of malicious...
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Comments on "Decomposition of Permutation Networks"
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Neuromorphic Binarized Polariton Networks
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VNFs reconfiguration in 5G networks
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Fair Optimization and Networks: A Survey
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Design and modeling of reliable networks
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Monitoring objects over networks
PublicationW pracy rozważa się uniwersalny pomysł na monitorowanie obiektów przemysłowych, firmowych i prywatnych, z inteligentnymi budynkami włšcznie. Rozmaite zadania diagnostyczne, sterownicze i zarzšdcze łatwo mogš być zintegrowane w taki projekt. Współczesne narzędzia technologii informacyjnych (IT) mogš być spożytkowane w celu stworzenia kompletnych i efektywnych systemów realizujšcych takie zadania. Oparłszy się na wysokich technologiach...
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Survivability issues in multilayer networks
PublicationW artykule rozważa się zagadnienia zabezpieczenia i odtwarzania w wielowarstwowych architekturach sieciowych w celu osiągnięcia określonego poziomu przeżywalności po awarii węzła lub łącza. Problem optymalizacji polega na znalezieniu dla każdej optycznej ścieżki aktywnej, przenoszącej dany strumień IP, węzłowo-rozłącznej optycznej ścieżki zabezpieczającej w taki sposób, by awaria pojedyńczego węzła lub łącza spowodowana atakiem...
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Graph models of clos networks
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Reliable Networks Design and Modeling
PublicationSłowo wstępne numeru specjalnego czasopisma Telecommunication Systems Journal
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Fiber-optic temperature sensor using low-coherence interferometry
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<title>Fiber optic probe for monitoring of drinking water</title>
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On The Application Of Fiber Optics In The Development Of Sensor Systems Of Intelligent Robots
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Assessment of water quality based on multiparameter fiber optic probe
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Modeling of active fiber Bragg grating underwater acoustic sensor.
PublicationW pracy przedstawiono wyniki modelowania nowego typu przetwornika hydroakustycznego wykorzystującego światłowodową siatkę Bragga. Siatka ta, domieszkowana jonami pierwiastków ziem rzadkich, pracuje jako laser z rozłożonym sprzężeniem zwrotnym, co pozwala na znaczne zwiększenie czułości tego prztwornika w porównaniu z rozwiązaniami wykorzystującymi siatki pasywne. W celu uzyskania równomiernego rozkładu naprężeń siatki zastosowano...
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Time-of-flight fiber optic sensors for strain and temperature measurement
PublicationW pracy przedstawiono światłowodowy sensor czasu przelotu do pomiaru odkształceń i temperatury mogący pracować zarówno w modzie transmisyjnym, jak i odbiciowym. W pomiarach czasu przelotu wykorzystano krótkie impulsy światłowodowe wprowadzane do jednodomowego światłowodu. Pod wpływem czynników zewnętrznych (temperatura, odkształcenie, siła rozciągająca) zmieniała się droga optyczna w światłowodzie, co powodowało zmiany czasu przelotu...
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The influence of small amount of substances present in tissue on the optical spectrum of immunosuppressive drug
PublicationIn this paper, we describe how commonly present in tissue substances - sodium chloride and glucose - affect the optical spectrum of an immunosuppressive drug (Cyclaid® by Apotex). Prepared samples were investigated using the spectrophotometer in the spectrum range from 250 nm to 1100 nm. The maximum wavelength shift calculated on the basis of measurement results is not bigger than the measurement wavelength step. So, it can be...
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Tailoring Electro/Optical Properties of Transparent Boron-Doped Carbon Nanowalls Grown on Quartz
PublicationCarbon nanowalls (CNWs) have attracted much attention for numerous applications in electrical devices because of their peculiar structural characteristics. However, it is possible to set synthesis parameters to vary the electrical and optical properties of such CNWs. In this paper, we demonstrate the direct growth of highly transparent boron-doped nanowalls (B-CNWs) on optical grade fused quartz. The effect of growth temperature...
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Screw displacement pile shaft deformations measured by vibrating wire and fiber optic systems during a static load test
PublicationThis paper describes a full scale static load test performed on a 400 mm diameter screw displacement pile equipped with four different strain measuring systems. Three types of vibrating wire strain gauges (VWSG) were used: global - retrievable, local attached to steel pipe and local concrete embedded. The fourth system was distributed fiber optic sensors based on Rayleigh back scattering (DFOS) - three in the pile cross section....
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Fast method for IEEE 802.16-2004 standard-based networks coverage measuring
PublicationThis paper presents the time and cost efficient method for measuring effective coverage of IEEE 802.16-2004 standard-based networks. This is done by performing a series of continuous measurements on the grid basis. Due to this kind of signal quality surveying, estimationof the probable coverage area can be made. It is significant that themethod is fast and is uses a standard customer equipment which makes it more accessible for...
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Selfish Attacks in Two-Hop IEEE 802.11 Relay Networks: Impact and Countermeasures
PublicationIn IEEE 802.11 networks, selfish stations can pursue a better quality of service through selfish MAC-layer attacks. Such attacks are easy to perform, secure routing protocols do not prevent them, and their detection may be complex. Two-hop relay topologies allow a new angle of attack: a selfish relay can tamper with either source traffic, transit traffic, or both. We consider the applicability of selfish attacks and their variants...
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Structure and optical measurements of Eu doped tellurium oxide thin films
Open Research DataThin films were deposited by magnetron sputtering method and simultaneously heated at 200 oC. Presence of Eu ions and their valence states was confirmed by X-ray photoemission spectroscopy measurements. The structure of the films as well as the influence of europium dopant on crystalline structure of the films was examined by X-ray diffraction method. ...
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Optical properties of TeOx gels doped with a mix of rare-earth ions
Open Research DataThe DataSet contains the UV-Vis spectra of the TeOx gels doped with a mix of rare-earth ions. The material was obtained by the sol-gel method. The starting solution was prepared by mixing telluric acid (precursor) with thetraetylene glycol, water, and ethanol. Next, the different molar concentration of rare-earth ions was added, nitrates were used...
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Frequency-Variant Double-Zero Single-Pole Reactive Coupling Networks for Coupled-Resonator Microwave Bandpass Filters
PublicationIn this work, a family of frequency-variant reactive coupling (FVRC) networks is introduced and discussed as new building blocks for the synthesis of coupled-resonator bandpass filters with real or complex transmission zeros (TZs). The FVRC is a type of nonideal frequency-dependent inverter that has nonzero elements on the diagonal of the impedance matrix, along with a nonlinear frequency-variation profile of its transimpedance...
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A novel genetic approach to provide differentiated levels of service resilience in IP-MPLS/WDM networks
PublicationThis paper introduces a novel class-based method of survivable routing for connection-oriented IP-MPLS/WDM networks, called MLS-GEN-H. The algorithm is designed to provide differentiated levels of service survivability in order to respond to varying requirements of end-users. It divides the complex problem of survivable routing in IP-MPLS/WDM networks into two subproblems, one for each network layer, which enables finding the...
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USING ARTIFICIAL NEURAL NETWORKS FOR PREDICTING SHIP FUEL CONSUMPTION
PublicationIn marine vessel operations, fuel costs are major operating costs which affect the overall profitability of the maritime transport industry. The effective enhancement of using ship fuel will increase ship operation efficiency. Since ship fuel consumption depends on different factors, such as weather, cruising condition, cargo load, and engine condition, it is difficult to assess the fuel consumption pattern for various types...
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Automatic Singing Voice Recognition EmployingNeural Networks and Rough Sets
PublicationCelem badań jest automatyczne rozpoznawanie głosów śpiewaczych w kategorii rodzaju i jakości technicznej śpiewu. W artykule opisano stworzoną bazę danych głosów, która zawiera próbki głosu śpiewaków profesjonalnych i amatorskich. W dalszej części opisano parametry zdefiniowane w oparciu o zjawiska biomechaniczne w narządzie głosu podczas śpiewania. W oparciu o stworzone macierze parametrów wytrenowano i porównano automatyczne klasyfikatory...
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Dempster-shafer theory-based trust and selfishness evaluation in mobile ad hoc networks
PublicationThe paper addresses the problem of selfishness detec-tion in mobile ad hoc networks. It describes an approach based on Dempster-Shafer theory of evidence. Special attention is paid to trust evaluation and using it as a metric for coping with (weighted) recommendations from third-party nodes. Efficiency and robustness of the pre-sented solution is discussed with an emphasis on resil-iency to false recommendations.
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Measurement of selected characteristics of low-coherence optical signal sources for optical coherence tomography
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Measurement of selected characteristics of low-coherence optical signal sources for optical coherence tomography
PublicationOCT to nowa metoda badania wewnętrznych struktur materiałów. Wśród wielu technik detekcji sygnału optycznego wykorzystywanych w OCT najpopularniejszą i najbardziej obiecującą jest OLCR (Opticla-Low Coherence Reflectomerty - reflektometria niskokoherentna). OLCR wykorzystuje szerokopasmowe źródła, których parametry, jak np.: charakterystyka widmowa, charakterystyka szumowa, determinują właściwości metrologiczne systemu OCT. W artykule...
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Raman diagnostics in manufacturing of polymer planar optical waveguides. Optical Fibers and Their Applications VIII.
PublicationZastosowano spektroskopię ramanowską do diagnostyki procesu syntezy nowego typu materiałów cienkowarstwowych polimerów hybrydowych, przeznaczonych do wytwarzania światłowodów planarnych. Zbadano poprawność poszczególnych etapów procesu technologicznego oraz strukturę molekularną materiału. Zademonstrowano możliwość kontroli procesu technologicznego w czasie rzeczywistym.
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Hybrid DUMBRA: an efficient QoS routing algorithm for networks with DiffServ architecture
PublicationDynamic routing is very important issue of current packet networks. It may support the QoS and help utilize available network resources. Unfortunately current routing mechanisms are not sufficient to fully support QoS. Although many research has been done in this area no generic QoS routing algorithm has been proposed that could be used across all network structures. Existing QoS routing algorithms are either dedicated to limited...
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Characterization of Optical and Electrical Properties of Transparent Conductive Boron-Doped Diamond thin Films Grown on Fused Silica
PublicationA conductive boron-doped diamond (BDD) grown on a fused silica/quartz has been investigated. Diamond thin films were deposited by the microwave plasma enhanced chemical vapor deposition (MW PECVD). The main parameters of the BDD synthesis, i.e. the methane admixture and the substrate temperature were investigated in detail. Preliminary studies of optical properties were performed to qualify an optimal CVD synthesis and film parameters...
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Deep Learning-Based LOS and NLOS Identification in Wireless Body Area Networks
PublicationIn this article, the usage of deep learning (DL) in ultra-wideband (UWB) Wireless Body Area Networks (WBANs) is presented. The developed approach, using channel impulse response, allows higher efficiency in identifying the direct visibility conditions between nodes in off-body communication with comparison to the methods described in the literature. The effectiveness of the proposed deep feedforward neural network was checked on...
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The application of neural networks in forecasting the influence of traffic-induced vibrations on residential buildings
PublicationTraffic-induced vibrations may cause the cracking of plaster, damage to structural elements and, in extreme cases, may even lead to the structural collapse of residential buildings. The aim of this article is to analyse the effectiveness of a method of forecasting the impact of vibrations on residential buildings using the concept of artificial intelligence. The article presents several alternative forecasting systems for which...
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Optical and photocatalytic properties of rare earth metal-modified ZnO quantum dots
PublicationA series of novel ZnO quantum dots modified with rare earth metals was successfully prepared by a simple sol-gel approach. The effects of types (Eu, Er, Tb, Yb, Ho, La) and amounts (from 0.09 to 0.45 mmol) of lanthanides on the optical properties, structural characterization and photocatalytic activity of ZnO/RE QDs were systematically investigated. The X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform...
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Modulo N Backoff Scheme for effective QoS differentiation and increased bandwidth utilization in IEEE 802.11 networks
PublicationThe paper presents a new "modulo N" channel access scheme for wireless Local Area Networks (WLANs). The novel solution derives from the Distributed Coordination Function (DCF) of the IEEE 802.11 standard, further elaborated as Enhanced Distribution Channel Access (EDCA) by the 802.11e draft specification. The main innovation concerns improvement of the binary exponential backoff scheme used for collision avoidance in 802.11 networks....
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Forwarding and optical indices of a graph
PublicationW pracy rozstrzygnięto dwa problemy dotyczące komunikacji wszyscy-do-wszystkich w grafach. Stwierdzono, że dla wersji skierowanej problemu parametry ''pi'' (maksymalne obciążenie krawędzi) i ''w'' (parametr chromatyczny) nie muszą być w ogólności sobie równe. Dla wersji nieskierowanej problemu pokazano, że wyznaczenie wartości zarówno ''pi'', jak i ''w'', jest w ogólności problemem NP-trudnym.
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Optical readout of superheated emulsions
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Optical fibers and their applications 2012
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Specialty optical fibers: revisited
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Development of optical sciences in Poland
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Optical Fibre Technology In Poland
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Optical Fibre Technology - A Digest
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Multicore Optical Fibres For Sensors
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