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Search results for: large-scale fading
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Large-scale converting waste coffee grounds into functional carbon materials as high-efficient adsorbent for organic dyes
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Distributed System for Monitoring of the Large Scale Infrastructure Structures Based on Analysis of Changes of its Static and Dynamic Properties
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A Large Scale Survey of the Great grey shrikeLanius excubitorin Poland: Breeding Densities, Habitat use and Population Trends
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Experimental and model-based evaluation of the role of denitrifying polyphosphate accumulating organisms at two large scale WWTPs in northern Poland
PublicationW pracy dokonano oceny zdolności denitryfikacyjnych bakterii fosforowych na przykładzie oczyszczalni ścieków ''Wschód'' w Gdańsku i ''Dębogórze'' w Gdyni. W tym celu wykonano serię testów z wykorzystaniem tzw. reaktora ''wsadowego'', które następnie były modelowane za pomocą modelu ASM2d. Badania wykazały, że tylko 32% bakterii fosforowych posiada zdolność do denitryfikacji. Szybkość denitryfikacji związana z aktywnością bakterii...
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The wintering distribution of Great Grey Shrike <I>Lanius excubitor</I> in Poland: predictions from a large-scale historical survey
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Practical Approach to Large-Scale Electronic Structure Calculations in Electrolyte Solutions via Continuum-Embedded Linear-Scaling Density Functional Theory
PublicationWe present the implementation of a hybrid continuum-atomistic model for including the effects of a surrounding electrolyte in large-scale density functional theory (DFT) calculations within the Order-N Electronic Total Energy Package (ONETEP) linear-scaling DFT code, which allows the simulation of large complex systems such as electrochemical interfaces. The model represents the electrolyte ions as a scalar field and the solvent...
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Uncertainty quantification of modal parameter estimates obtained from subspace identification: An experimental validation on a laboratory test of a large-scale wind turbine blade
PublicationThe uncertainty afflicting modal parameter estimates stems from e.g., the finite data length, unknown, or partly measured inputs and the choice of the identification algorithm. Quantification of the related errors with the statistical Delta method is a recent tool, useful in many modern modal analysis applications e.g., damage diagnosis, reliability analysis, model calibration. In this paper, the Delta method-based uncertainty...
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Radiation-induced Changes in Levels of Selected Proteins in Peripheral Blood Serum of Breast Cancer Patients as a Potential Triage Biodosimeter for Large-scale Radiological Emergencies
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Large‐Scale Traveling Ionospheric Disturbances Over the European Sector During the Geomagnetic Storm on March 23–24, 2023: Energy Deposition in the Source Regions and the Propagation Characteristics
PublicationMultiple Large-Scale Traveling Ionospheric Disturbances (LSTIDs) are observed in the European sector in both day-time and night-time during the magnetic storm on March 23–24, 2023. The Total Electron Content (TEC) observation from a network of GNSS receivers shows the propagation of LSTIDs with amplitudes between around 0.5 and 1 TECU originating from auroral and polar cusp regions down to southern Europe (35°N) with velocities...
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Impact of Large-scale urban interventions on contemporary city centers. Gdansk case study. Wpływ przedsiewzięć urbanistycznych dużej skali na centra miast. Studium przypadku Gdańska
PublicationLarge scale urban interventions have become a common development practice in cotemporary cities, allowing achieving rapid changes in their urban structure. They can be analyzed taking into account various perspectives. Some of them include planning and development models, transformation of brownfields and other types of distressed urban areas, as well as consequences and results of their implementation in existing urban structures....
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Serce dzielnicy w stanie embrionalnego rozwoju - śrómieście reurbanizowanego wielkiego osiedla w polskim mieście metropolitalnym = Heart of the districts in embrional faze of development -city core structures for the large scale housing in Polish metropolitan city
PublicationW ostatnich 10 latach obserwowana jest intensyfikacja procesu uzupełniania zabudowy śródmieścia Gdańska. Jest to z jednej strony kontynuacja odbudowy historycznego centrum miasta, z drugiej zaś rewitalizacja dzielnic o przewadze zabudowy z początku wieku obejmująca śródmiejskie tereny powojskowe i poprzemysłowe m.in dawnej Stoczni Gdańskiej, koszaty we Wrzeszczu. Liczne komercyjne projekty prowadzą do istotnych dogęszczeń funcjami...
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[Chapter] 22. Application of physical modeling to study combustion process-es and flow patterns in large-scale boilers and furmaces. W: Optical me- thods and data processing in heat and fluid flow. Ed. C. Greated, J. Cos-grove, J.M. Buick. Bury St. Edmunds. London: Profess. Eng. Publ.**2002 s. 267-277, 4 rys. bibliogr. 6 poz. Zastosowanie modelowania fizycznego do badania procesów spalania pola prze- pływu w przemysłowych kotłach i piecach.
PublicationRozdział zawiera wyniki badań modelowania fizycznego dwuwymiarowego i trój-wymiarowego pola przepływu i procesów spalania w wybranych urządzeniachprzemysłowych.
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Fading Characteristics for Dynamic Body-to-Body Channels in Indoor and Outdoor Environments
PublicationThis paper presents an analysis of the fading characteristics in dynamic body-to-body channels, based on measurements performed at 2.45 GHz in indoor and outdoor environments. The statistical analysis of the small- and large-scale fading shows that the Nakagami Distribution is the best model for the former and the Log-Normal one for the latter. An important influence of body shadowing...
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Fading Analysis in Off-Body Channels in a Straight Metallic Corridor in a Passenger Ferry Environment
PublicationThis paper presents a fading analysis for Body Area Networks off-body communications at 2.45 GHz in a passenger ferry environment. The results are based on measurements performed for dynamic scenarios in a straight metallic corridor. Two components, extracted from instantaneous system loss values, have been analysed: small- and large-scales fading, separately for each scenario. Well-known probability distribution functions have...
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An Off-Body Narrowband and Ultra-Wide Band Channel Model for Body Area Networks in a Ferryboat Environment
PublicationIn the article an off-body narrowband and ultra-wide band channel model for body area networks in a ferryboat environment is described. Considering the limited number of publications there is a need to develop an off-body channel model, which will facilitate the design of radio links, both from the multimedia services provider and the security point of view, for body area networks in this atypical environment. A mobile heterogeneous...
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Characterization of slow and fast fading in off-body communication at 2.45 GHz with space diversity scheme in indoor environment
PublicationThe characterization of slow and fast fading in Wireless Body Area Networks with space diversity scheme has been presented. The analysis, based on the measurements at 2.45 GHz in indoor environment, has shown that for all investigated configurations of receiving wearable antennas the correlation coefficient values of received signals’ parameters are below the assumed value of 0.5, being close to zero for the vast majority of cases. It...
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Characterization of Slow and Fast Fading in Off-Body Communication at 2.45 GHz with Space Diversity Scheme in an Indoor Environment
PublicationThe characterization of slow and fast fading in wireless body area networks with space diversity scheme has been presented. The analysis, based on the measurements at 2.45 GHz in an indoor environment, has shown that for all investigated configurations of receiving wearable antennas, the correlation coefficient values of the received signals’ parameters are below the assumed value of 0.5, being close to zero for the vast majority...
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Fading Modeling in Maritime Container Terminal Environments
PublicationIn this paper, an analytical model for slow and fast fading effects in maritime container terminals is derived, from fitting distributions to the results of measurements performed in an actual operational environment. The proposed model is composed of a set of equations, enabling to evaluate fading statistical distribution parameters for different system and environments conditions, as a function of frequency, base station antenna...
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Fading Modelling in Dynamic Off-Body Channels
PublicationThis paper presents an off-body fading channel model for Body Area Networks. The proposed model, based on both simulations and measurements at 2.45 GHz in a realistic indoor environment, consists of three components: mean path loss, body shadowing, and multipath fading. The first is modelled as a log function of distance, the path loss exponent being in between 0.4 and 1.6. A statistical perspective is taken for the other two components,...
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Fading Modelling in Dynamic Off-Body Channels
PublicationThis paper presents an off-body fading channel model for Body Area Networks (BANs) in indoor environments. The proposed model, which is based on both simulations and measurements in a realistic environment, consists of three components: mean path loss, body shadowing, and multipath fading. Seven scenarios in an indoor environment (a medium-size room with furniture, mostly consisting of wooden tables and chairs) have been measured:...
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Fast Fading Characterization for Body Area Networks in Circular Metallic Indoor Environments
PublicationWith the increasing development of 5G and Body Area Network based systems being implemented in unusual environments, propagation inside metallic structures is a key aspect to characterize propagation effects inside ships and other similar environments, mostly composed of metallic walls. In this paper, indoor propagation inside circular metallic structures is addressed and fast fading statistical distributions parameters are obtained...
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Fast Fading Influence on the Deep Learning-Based LOS and NLOS Identificationin Wireless Body Area Networks
PublicationIn the article, the fast fading influence on the proposed DL (Deep Learning) approach for LOS (Line-of-Sight) and NLOS (Non-Line-of-Sight) conditions identification in Wireless Body Area Networks is investigated. The research was conducted on the basis of the off-body communication measurements using the developed mobile measurement stand, in an indoor environment for both static and dynamic scenarios. The measurements involved...
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Territorial Aspects of Entrepreneurial Activity in Polish Suburban Zones
PublicationGlobalization has led to an increased correlation and integration of various fields in modern civilization, including those connected with allocation of entrepreneurial functions. Connection, on a global scale, has shown an increased significance of worldwide corporations. Territorial allocation of the entrepreneurial function has become the subject of translocation and revaluation. Translocation can be understood as the change...
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Bandwidth Dependence of the Propagation Channel in Circular Metallic BAN Environments
PublicationIn this paper, the bandwidth dependence of the propagation channel for Body Area Networks (BANs) in circular metallic environments is addressed and models are proposed to evaluate the appropriate short-term fading margins that should be considered as a function of the system bandwidth. The deployment of BANs in metallic indoor environments, such as ships, factories, warehouses and other similar environments, involves additional...
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An Empirical Model for the Polarisation Characteristics of Indoor Off-Body Channels
PublicationThis paper presents an analysis of the polarisation characteristics for the channel in dynamic off-body communications, and an empirical channel model, based on measurements performed at 2.45 GHz in an office environment. Body presence and propagation conditions have a strong influence on signal depolarisation. The model assumes three components for the total path loss: mean path loss, represented by a log-distance function with...
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An Off-Body Narrowband and Ultra-Wide Band Channel Model for Body Area Networks in a Ferry Environment
PublicationIn the article an off-body narrowband and ultra-wide band channel model for Body Area Networks in a ferry environment is described. A mobile, heterogeneous measurement stand, that consists of three types of devices: miniaturized mobile nodes, stationary reference nodes and a data acquisition server was developed. A detailed analysis of both radio channels parameters in untypical indoor environment was carried out. An analysis of...
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Measurement of Coherence Bandwidth in UHF Radio Channels for Narrowband Networks
PublicationThis paper presents results of investigation on the coherence bandwidth of narrowband radio channels in 430MHz band. The coherence bandwidth values were estimated froma power delay profile obtained by recording CDMA2000 forward channel signals during real-fieldmeasurements in various environments:mediumcity, flat terrain, and hilly terrain in northern Poland.The results of measurements are compared with characteristic parameters...
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Estimation of Rician K-factor Values in Urban Terrain
PublicationThis paper presents results of Rician K-factor estimation from CDMA2000 downlink signals recorded in the area of medium city. Signal and data processing methods used to estimate fading parameters are also briefly described.
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An Empirical System Loss Model for Body Area Networks in a Passenger Ferry Environment
PublicationThis paper presents a general empirical system loss model for estimating propagation loss in Body Area Networks in off-body communications at 2.45 GHz in a passenger ferry environment. The model is based on measurements, which were carried out in dynamic scenarios in the discotheque passenger ferry environment. The model consists of three components: mean system loss, attenuation resulting from the variable antenna position on...
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An Empirical System Loss Model for Body Area Networks in a Passenger Ferry Environment
PublicationThis paper presents a general empirical system loss model for estimating propagation loss in Body Area Networks in off-body communications at 2.45 GHz in a passenger ferry environment. The model is based on measurements, which were carried out in dynamic scenarios in the discotheque passenger ferry environment. The model consists of three components: mean system loss, attenuation resulting from the variable antenna position on...
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Characteristics of the Polarised Off-Body Channel in Indoor Environments
PublicationThis paper addresses the depolarisation effect in off-body Body Area Networks channels, based on measurements performed at 2.45 GHz in an indoor environment. Seven different scenarios, involving both static and dynamic users, were considered, taking a statistical perspective. The analysis of the cross-polarisation discrimination is performed, as well as the analysis of path loss in co- and cross-polarised channels. Results show...
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Method of selective fading as a educational tool to study the behaviour of prestressed concrete elements under excess loading
PublicationPrestressed structures are a key to realization of the boldest architectural ideas, characteristic feature of prestressed structure is better use of concrete material properties by insertion of internal forces. Learning about pre-stressed reinforced concrete structures is an integral part of Graduate Studies Program in construction engineering. Know-how of geometry change patterns in prestressed concrete elements under certain...
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Proposal of a System Loss Model for Body Area Network in Passenger Ferry Environment
PublicationIn the paper, proposal of an empirical off-body system loss model for Body Area Networks working in a passenger ferry environment at 2.45 GHz has been presented. The measurements were carried out for dynamic scenarios in the discotheque passenger ferry environment. The general model formula consists of three components: mean system loss, attenuation resulting from the variable antenna position on the human body, and attenuation...
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An Off-Body Channel Model for Body Area Networks in Indoor Environments
PublicationThis paper presents an off-body channel model for body area networks (BANs) in indoor environments. The proposed model, which is based on both simulations and measurements in a realistic environment, consists of three components: mean path loss, body shadowing, and multipath fading. Seven scenarios in a realistic indoor office environment containing typical scatterers have been measured: five were static (three standing and two...
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On bidirectional preestimates and their application to identification of fast time-varying systems
PublicationWhen applied to the identification of time-varying systems, such as rapidly fading telecommunication channels, adaptive estimation algorithms built on the local basis function (LBF) principle yield excellent tracking performance but are computationally demanding. The subsequently proposed fast LBF (fLBF) algorithms, based on the preestimation principle, allow a substantial reduction in complexity without significant performance...
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Mural i jego rola w przestrzeni zurbanizowanej
PublicationCzym tak naprawdę jest mural? Definicji jest bardzo wiele. Według Słownika języka polskiego PWN mural to „wielkie malowidło wykonane bezpośrednio na ścianie budynku”. Pierwotnymi malowidłami tego typu były prace naskalne z epoki paleolitu. Następnie ważnymi epokami dla rozwoju tego typu prac był starożytny Egipt i starożytny Rzym. Samo słowo „mural” pochodzi z języka hiszpańskiego (h. mural – ścienny; malarstwo ścienne). To dzięki...
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Problemy planowania rozwoju systemu transportowego w obszarach metropolitalnych – przykład Obszaru Metropolitalnego G-G-S
PublicationProblemy rozwoju systemów transportowych w metropoliach wynikają ze specyfiki tych obszarów, ich skali i struktury przestrzennej. Obszary te charakteryzują się dużą wewnętrzną integracją funkcjonalną oraz dobrze rozwiniętą siecią transportową. Dynamicznie rozwijające się obszary metropolitalne mają odrębne systemy zarządzania finansami, rozwią- zania prawne oraz administrację, a także własne organy planowania i zarządzania, które...
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Synchronization system for underwater acoustic communications using in shallow waters
PublicationA reliable synchronization system of the transmitted data frame has a significant impact on the efficiency of the underwater communication system. This applies in particular to communication systems dedicated to work in shallow waters, where the phenomenon of multipath permanently occurs. To overcome these difficulties, the concept of a synchronization system consisting of two broadband signals of opposite monotonicity was presented....
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Multiple-Input Multiple-Output Technique for Underwater Acoustic Communication System
PublicationThe performance of an underwater acoustic communication (UAC) system is limited due to tough propagation conditions in the UAC channel. Multiple-Input Multiple-Output (MIMO) technique can improve the reliability of the data transmission system, increase its speed, increase its range, and reduce the energy consumption. The paper presents an implementation method of MIMO technique in the form of coding the Space-Time Block Code and...
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MOST PODWIESZONY kreowanie przestrzeni i konsekwencje konstrukcyjne
PublicationProjektowanie i budowa - wyzwania dla projektantów i wykonawców mostów. Mosty podwieszone i wiszące ich estetyka i konsekwencje strukturalne. Artykuł dotyczy aspektów estetycznych i konstrukcyjnych zaprojektowanych pylonów dla mostów podwieszonych lub wiszących. Autor zwraca uwagę na fakt, że niezwykłe rozwiązanie konstrukcyjne zastosowane do kładki lub małego wiaduktu może działać prawidłowo dzięki zjawiskom efektu skali. Nadzwyczajne...
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Performance of Coherent Modulation Scheme Used in Acoustic Underwater Communication System
PublicationThe development of an acoustic underwater communication system for shallow waters is still a big scientificand construction challenge. Currently, non-coherent modulations in combination with strong channel coding are used to achieve reliable communication with low rate in such a channel. To obtain transmission with a higher transmission rate, it is required to use coherent modulation. This paper presents the assumptions of such...
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Underwater acoustic communication system using broadband signal with hyperbolically modulated frequency
PublicationThe implementation of reliable acoustic underwater communication in shallow waters is a scientific and engineering challenge, mainly due to the permanent occurrence of the multipath phenomenon. The article presents the concept of a transmission system using a broadband signal with hyperbolically modulated frequency (HFM) to transmit data symbols and synchronize data frames. The simulation tests were carried out in channels with...
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Red Algae – An Alternative Source of Carbon Material for Energy Storage Application
PublicationNew electrode material obtained by pyrolysis of aquatic biomass macro (red algae) soaked with glucose solution has been characterized by SEM, EDX and Raman spectroscopy. Graphitized carbon was identified by Raman spectroscopy. Galvanostatic cyclic polarization of the materials in contact with 1M LiPF6 electrolyte in EC:DMC (1:1 v/v) and Li as a counter electrode was performed. Specific capacity of the novel material was enhanced...
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Surface finite viscoelasticity and surface anti-plane waves
PublicationWe introduce the surface viscoelasticity under finite deformations. The theory is straightforward generalization of the Gurtin–Murdoch model to materials with fading memory. Surface viscoelasticity may reflect some surface related creep/stress relaxation phenomena observed at small scales. Discussed model could also describe thin inelastic coatings or thin interfacial layers. The constitutive equations for surface stresses are...
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Problemy mieszkaniowe w budującej się Gdyni, „mieście poszukiwaczy złota”
PublicationMiasto Gdynia, zbudowane zupełnie od podstaw w przeciągu kilkunastu lat, na przestrzeni lat 1923-1939, stanowiło jedno z najważniejszych przedsięwzięć inwestycyjnych II Rzeczypospolitej. Szybka budowa dwóch składowych tego nowoczesnego ośrodka, jakimi były port i miasto, wiązała się nierzadko z nowymi, wcześniej trudnymi do przewidzenia wyzwaniami natury planistycznej i organizacyjnej. W początkowych latach budowy Gdyni zapewnienie...
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Assessment of User Mobility’s Influence on System Loss in Several Body-to-Body Scenarios
PublicationIn this paper, Body-to-Body communications in indoor and outdoor environments for different on-body antenna configurations and different mobility scenarios were studied, based on system loss measurements at 2.45 GHz. The main objective is to properly characterise the influence of the Transmitter-Receiver configuration on system loss and fast fading behaviour, the latter being modelled by the Rice Distribution. Globally, it is observed...
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Ultrawideband transmission in physical channels: a broadband interference view
PublicationThe superposition of multipath components (MPC) of an emitted wave, formed by reflections from limiting surfaces and obstacles in the propagation area, strongly affects communication signals. In the case of modern wideband systems, the effect should be seen as a broadband counterpart of classical interference which is the cause of fading in narrowband systems. This paper shows that in wideband communications, the time- and frequency-domain...
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Electrochemical Characterization of Gelatine Derived Ceramics
PublicationNew materials obtained by pyrolysis of gelatine (G) and poly(1,2-dimethylsilazane) (PSN) (weight ratio: G/PSN 70/30) at temperatures 700 and 900 °C were characterized by SEM and Raman spectroscopy. The presence of ceramics influences on the cluster size of the materials. Electrochemical tests were performed by cyclic voltammetry and galvanostatic cyclic polarization. The capacity of G/PSN was 464 and 527 mAh/g for materials pyrolysed...
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Overview of Fading Channel Modeling
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Measurements of Path Loss in Off-Body Channels in Indoor Environments
PublicationThis paper presents a measurements of the path loss for validation of a statistical model for off-body radio channels in an indoor multipath environment, which considers the distance dependent mean path loss, and describes body shadowing and fast fading components in a statistical way. The measurement equipment and propagation indoor environment have been presented. Two different bodies and five static and two walking scenarios...