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Search results for: INDOOR AIR QUALITY
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Badania jakości usług szybkiej transmisji danych z wykorzystaniem turbokodowania w systemie UMTS.
PublicationW pracy przedstawiono budowę kodera oraz dekodera turbokodu pracującego w oparciu o algorytm SOVA w systemie radiokomunikacyjnym trzeciej generacji UMTS. Omówiono wyniki badań symulacyjnych jakości transmisji z szybkością 384 kb/s z wykorzystaniem turbokodowania. Badania przeprowadzono dla obu kierunków transmisji w środowiskach Indoor Office B oraz Outdoor to Indoor & Pedestrian B.
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Modelowanie dokładności radiolokalizowania w różnych warunkach środowiskowych przy wykorzystaniu interfejsu radiowego 5G-NR
PublicationW artykule przedstawiono wyniki eksperymentalnych badań dokładności estymacji położenia terminala użytkownika korzystającego~z interfejsu radiowego 5G-NR. W środowisku miejskim dokonano rejestracji rzeczywistych sygnałów sieci 5G, a następnie przeprowadzono badania numeryczne. Celem było zweryfikowanie różnic dokładności estymacji położenia w trzech różnych środowiskach: wewnątrz- i zewnątrzbudynkowym oraz tzw. deep-indoor.
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Unconventional and user-friendly sampling techniques of semi-volatile organic compounds present in an indoor environment: An approach to human exposure assessment
PublicationThe commonly applied solutions used to assess the potential risk of human exposure to semi-volatile organic compounds (SVOCs) are based on the investigation of biological samples collected in an invasive or non-invasive manner. For SVOCs, which are typically introduced to humans through the respiratory system, dermal adsorption, or digestive system, sampling solutions generally used in the indoor environments are classified as...
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A VISION-BASED UNMANNED AERIAL VEHICLE NAVIGATION METHOD
PublicationThe satellite navigation systems are the main position sources for unmanned aerial vehicles (UAVs). This fact limits the area of UAVs operation to the places where radio signals is visible for a satellite navigation system receiver, mounted on the vehicle-outdoor navigation. Closed spaced are unavailable for vehicles which navigation is based on global satellite navigation systems (GNSS). Miniature UAV (MiniUAV) is able to operate...
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‘Personas for lighting’. Three methods to develop personas for the indoor lighting environment
PublicationThe objective of this research is to describe and compare three different methods of generating ‘persona for lighting’ to envision users’ behaviour within the lighting environment. ‘Personas’ are used to represent typical users, highlighting their needs, perspectives, and expectations to aid user-centric design approaches. The researchers looked for the most useful method of shaping ‘personas for lighting’ to learn about users’...
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Influence of a Radio Frequency on RF Fingerprinting Accuracy Based on Ray Tracing Simulation
PublicationIn this paper the influence of a radio signal frequency on performance of Indoor Positioning System based on fingerprinting has been examined using ray-tracing simulations. It has been simulated how spatial distribution of an RF signal strength change with the signal’s frequency. The results were used to show its’ impact on the behavior of localization algorithms that are employing RSS measurements to determine node’s position...
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Sensors and System for Vehicle Navigation
PublicationIn recent years, vehicle navigation, in particular autonomous navigation, has been at the center of several major developments, both in civilian and defense applications. New technologies, such as multisensory data fusion, big data processing, or deep learning, are changing the quality of areas of applications, improving the sensors and systems used. Recently, the influence of artificial intelligence on sensor data processing and...
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Analogue GPS repeater
PublicationThis article concerns the problem of difficulty in correct indoor Global Positioning System (GPS) signals reception due to attenuation. Radio signal repeaters are proposed as means to solve this problem. Firstly, the GPS signal characteristics are described, emphasizing their low power in the point of reception. In the second part, various applications of GPS signal repeater, where indoor GPS signals reception is required, are...
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New Method for Increasing Precision of Position Estimation of a Moving Person in Hybrid Inertial Navigation System
PublicationIn this article a new method for increasing precision of position estimation of inertial navigation in hybrid localization system with reduced number of reference nodes for radio distance measurements is presented. Measuring tests were carried out to verify precision of position estimation of moving person in indoor environment.
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New Method for Increasing Precision of Position Estimation in Hybrid Inertial Navigation System
PublicationIn article new method for increasing precision of position estimation by using inertial navigation in hybrid localization system with reduced number of reference nodes for radio distance measurements was presented. Measuring campaign using developed measuring stand were carried out to verify precision of position estimation of moving person in indoor environment.
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Research and Analysis of Accuracy of Location Estimation in Inertial Navigation System
PublicationIn the article the research and analysis of digital signal processing and its influence on accuracy of location estimation in developed inertial navigation system was presented. The purpose of the system is to localize moving people in indoor environment. During research a measuring unit for recording selected movement parameters was made. In the article were also described author’s inertial navigation algorithms.
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Determination of polybrominated diphenyl ethers in house dust using standard addition method and gas chromatography with electron capture and mass spectrometric detection
PublicationMonitoring of the environmental fate of polybrominated diphenyl ethers (PBDEs) involves determination of their concentration in air, airborne particles and settled dust. This requires the implementation of appropriate analytical tools like measuring instruments, reference materials and analytical procedures. In this study an analytical procedure was developed for determining PBDEs in samples with a complex matrix composition. The...
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Online Volatile Compound Emissions Analysis Using a Microchamber/Thermal Extractor Coupled to Proton Transfer Reaction-Mass Spectrometry
PublicationIndoor air is a complex and dynamic mixture comprising manifold volatile organic compounds (VOCs) that may cause physiological and/or psychological discomfort, depending on the nature of exposure. This technical note presents a novel approach to analyze VOC emissions by coupling a microchamber/thermal extractor (μ-CTE) system to a proton transfer reaction-mass spectrometer (PTR-MS). This configuration provides an alternative to...
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Porównanie efektywności kodów LDPC
PublicationW referacie zaprezentowano porównanie wyników badań symulacyjnych jakości transmisji z wykorzystaniem kodów LDPC w interfejsie radiowym systemu UMTS. Badania symulacyjne zostały przeprowadzone dla szybkości transmisji 144 kb/s w środowisku propagacyjnym Outdoor to Indoor & Pedestrian B. W referacie przedstawiono również zasadę działania i algorytmy dekodowania kodów LDPC.
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Technologie prośrodowiskowe dla budynków miejskich
PublicationWspółczesne duże miasta na całym świecie charakteryzują się dużą i wciąż rosnącą intensywnością zabudowy. Jest to tendencja utrwalona, którą pogłębia idea „miasta zwartego” jako rozwiązania dla problemu nadmiernego rozrastania terytorialnego i rozpraszania się struktury terenów miejskich. Jednocześnie realną potrzebą współczesnych miast jest poprawa jakości ich środowiska (eliminacja zanieczyszczeń, minimalizacja zjawiska miejskiej...
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Survey of Radio Navigation Systems
PublicationAt present, there is a growing demand for radio navigation systems, ranging from pedestrian navigation to consumer behavior analysis. These systems have been successfully used in many applications and have become very popular in recent years. In this paper we present a review of selected wireless positioning solutions operating in both indoor and outdoor environments. We describe different positioning techniques, methods, systems,...
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Series-Slot-Fed Circularly Polarized Multiple-Input-Multiple-Output Antenna Array Enabling Circular Polarization Diversity for 5G 28-GHz Indoor Applications
PublicationIn this paper, a four-element circularly polarized series-slot-fed multiple-input-multiple-output (MIMO) antenna array with circular polarization diversity is presented. The proposed design utilizes a combination of 45-degree inclined slots and a straight microstrip line feeding technique. The two antennas are designed to operate with the opposite sense of circular polarization (CP). CP is achieved by placing a patch of just about...
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Performance of data transmission in UMTS with turbo code about decreased number of states
PublicationIn the paper a structure of turbo encoder and decoder about decreased number of states has been described. The simulation results of transmission performance based on turbo coding without the reduction of the number of iterations for the uplink and downlink of WCDMA/FDD interface have been presented. The SOVA algorithm for turbo decoding has been used. The investigations have been carried out for Outdoor to Indoor & Pedestrian...
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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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Air Pollution: Monitoring
PublicationThe entry presents an overview of the issues in the field of air pollution monitoring. At the beginning, the general objectives of air monitoring, ambient air quality standards for so-called criteria pollutants, and their sources are discussed. In the next part, both analytical methods and instruments for monitoring of ambient air and stack gases are briefly presented. Additionally, other approaches used in air pollution monitoring,...
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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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Embedded device for indoor positioning of mobile terminals in ISM 2.4 GHz frequency band integrated with ESPAR antenna
PublicationIn the era of multifunctional mobile phones, wireless positioning is one of the most important branches of telecommunications development. This functionality is possible thanks to global positioning systems such as GPS, whose services are available to every average user. Global systems, however, suffer from their low accuracy in confined environments such as forests and building interiors. A popular...
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Badanie efektywności mechanizmu redukcji liczby iteracji turbodekodera w systemie UMTS
PublicationStreszczenie: W referacie przedstawiono budowę turbokodera zastosowanego w systemie UMTS i dekodera turbokodu z mechanizmem redukcji liczby iteracji wykorzystującym informację o przekroczeniu zadanego progu przez wielkość logarytmu stosunku prawdopodobieństw a-posteriori LLR w turbodekoderze Zostały porównane i omówione wyniki badań symulacyjnych dla obu kierunków transmisji w środowisku propagacyjnym miejskim wokoło-budynkowym...
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Badania jakości turbodekodowania z mechanizmem redukcji liczby iteracji w systemie UMTS
PublicationW referacie została przedstawiona budowakodera oraz dekodera turbokodu pracującego w oparciuo algorytm SOVA z zastosowanym mechanizmem redukującymliczbę iteracji w systemie UMTS. Zostały porównanei omówione wyniki badań symulacyjnych przeprowadzonychdla obu kierunków transmisji w środowisku propagacyjnymOutdoor to Indoor & Pedestrian B dla trzech szybkościtransmisji danych 64 kb/s, 144 kb/s i 384 kb/s, w przypadkuzastosowania mechanizmu...
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The Relationships Between BTEX, NOx, and O3 Concentrations in Urban Air in Gdansk and Gdynia, Poland
PublicationThis paper presents the results of atmospheric air quality research conducted in the areas of two shipyard cities: Gdansk and Gdynia (Poland), in the period between March and December 2011. The purpose of the research was focused on determination of benzene, toluene, ethylbenzene, and xylenes (BTEX) compounds in atmospheric air. Passive sampling technique, with Radiello® diffusive passive samplers, was used for BTEX sample collection...
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Adaptive Positioning Systems Based on Multiple Wireless Interfaces for Industrial IoT in Harsh Manufacturing Environments
PublicationAs the industrial sector is becoming ever more flexible in order to improve productivity, legacy interfaces for industrial applications must evolve to enhance efficiency and must adapt to achieve higher elasticity and reliability in harsh manufacturing environments. The localization of machines, sensors and workers inside the industrial premises is one of such interfaces used by many applications. Current localization-based systems...
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Person Tracking in Ultra-Wide Band Hybrid Localization System Using Reduced Number of Reference Nodes
PublicationIn this article a novel method of positional data integration in an indoor hybrid localization system combining inertial navigation with radio distance measurements is presented. A point of interest is the situation when the positional data and the radio distance measurements are obtained from less than thee reference nodes and it is impossible to unambiguously localize the moving person due to undetermined set of positional equations....
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Customization of UWB 3D-RTLS Based on the New Uncertainty Model of the AoA Ranging Technique
PublicationThe increased potential and effectiveness of Real-time Locating Systems (RTLSs) substantially influence their application spectrum. They are widely used, inter alia, in the industrial sector, healthcare, home care, and in logistic and security applications. The research aims to develop an analytical method to customize UWB-based RTLS, in order to improve their localization performance in terms of accuracy and precision. The analytical...
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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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An Approach to Mean Path Loss Model Estimation for Off-Body Channels
PublicationThis paper presents an approach to estimation of the mean path loss model parameters in off-body Body Area Networks channels. In this approach, the path loss exponent is constrained to a value obtained for the line-of-sight (LoS) propagation in the co-polarised channel, considering a generalised static scenario. The comparison of the goodness of fit between the proposed approach and other approaches, for a set of measurements obtained...
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BADANIE JAKOŚCI TRANSMISJI W KANALE RADIOWYM Z PROPAGACJĄ WIELODROGOWĄ DLA INTERFEJSU RADIOWEGO MC-CDMA
PublicationW referacie zostały zaprezentowane wyniki badań symulacyjnych jakości transmisji w interfejsie radiowym MC-CDMA dla transmisji w kanale z propagacją wielodrogową. Symulacje zostały przeprowadzone w środowisku miejskim okołobudynkowym dla użytkowników pieszych i w pojazdach (ang. Outdoor to Indoor and Pedestrian Environment). Środowisko to charakteryzuje się małymi mocami nadajników i małymi promieniami komórek. W symulacjach terminal...
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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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Wideband Off-Body Channel Characteristics with Dynamic User
PublicationThis paper presents the preliminary results of a dynamic off-body channel characterisation study, based on wideband measurements at 5.8 GHz in an indoor environment. The Channel Impulse Response (CIR) was measured for a scenario with the user approaching and departing from the off-body antenna. A CIR deconvolution procedure was performed jointly in two polarisations, and the received signal power, Cross-Polarisation Discrimination...
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The home-made in situ passive flux sampler for the measurement of monoterpene emission flux: preliminary studies
PublicationThe paper presents the construction and metrological characteristics of the home-made in situ passive flux sampler, an analytical tool representing small-scale emission chambers working in situ and passively sampling analytes from the gaseous phase. The sorption element was a cylindrical container made of stainless steel net, packed with a carbon sorbent bed-graphitized charcoal, Carbograph 4 (35/50mesh). The recommended working/exposure...
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Effect of band gap on power conversion efficiency of single-junction semiconductor photovoltaic cells under white light phosphor-based LED illumination
PublicationOn the basis of the detailed balance principle, curves of efficiency limit of single-junction photovoltaic cells at warm and cool white light phosphor-based LED bulbs with luminous efficacy exceeding 100 lm/W have been simulated. The effect of energy band gap and illuminance on the efficiencies at warm and cool light is discussed. The simulations carried out show that maximum power conversion efficiency at 1000 lx reaches 52.0%...
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On the Usefulness of the Generalised Additive Model for Mean Path Loss Estimation in Body Area Networks
PublicationIn this article, the usefulness of the Generalised Additive Model for mean path loss estimation in Body Area Networks is investigated. The research concerns a narrow-band indoor off-body network operating at 2.45 GHz, being based on measurements performed with four different users. The mean path loss is modelled as a sum of four components that depend on path length, antenna orientation angle, absolute difference between transmitting...
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Badanie i analiza efektywności alokacji strumieni danych w heterogenicznej sieci WBAN
PublicationW niniejszej dysertacji doktorskiej poddano dyskusji efektywność alokacji strumieni danych w heterogenicznej radiowej sieci WBAN (Wireless Body Area Networks). Biorąc pod uwagę dynamiczny rozwój nowoczesnych sieci radiokomunikacyjnych piątej generacji (5G), którego część stanowią radiowe sieci działające w obrębie ciała człowieka, bardzo ważnym aspektem są metody maksymalizujące wykorzystanie dostępnych zasobów czasowo –częstotliwościowych...
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Verification of ESPAR Antennas Performance in the Simple and Calibration Free Localization System
PublicationThis paper presents the results of simulations and measurements of an indoor localization system that uses Electronically Steerable Parasitic Array Radiator (ESPAR) antennas with switched directional beam. Proposed antennas are dedicated for 2.4GHz ISM low-cost applications where determination of the incoming signal is required. The antennas performance is analyzed and verified with relation to positioning methods based on the...
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Stereo image visualization for a VISROBOT system
PublicationThe article describes a novel approach to robotic vision in mobile robot systems. The system implements a Visrobot system which implements a generic idea of using mobile robots for exploring an indoor environment. The task of such a robot is to visualize a stereo image properly for an operator. The system uses different stereo baseline values. Variable baseline can result in increasing depth resolution for distant objects. We assume...
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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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Performance improvement of NN based RTLS by customization of NN structure - heuristic approach
PublicationThe purpose of this research is to improve performance of the Hybrid Scene Analysis – Neural Network indoor localization algorithm applied in Real-time Locating System, RTLS. A properly customized structure of Neural Network and training algorithms for specific operating environment will enhance the system’s performance in terms of localization accuracy and precision. Due to nonlinearity and model complexity, a heuristic analysis...
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Mobile Systems (Portable, Handheld, Transportable) for Monitoring Air Pollution
PublicationThe monitoring and analysis of atmospheric air pollutants is a rapidly developing branch of analytical chemistry. The in situ analysis of atmospheric air quality using mobile instrumentation is becoming routine. The article provides information on devices used in various kinds of mobile laboratories. It reviews the portable gas chromatographs and handheld devices used for detecting and determining specific harmful substances in...
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Evaluation of the Commercial Electrochemical Gas Sensors for the Monitoring of CO in Ambient Air
PublicationAir pollution is a growing concern of civilized world, which has a significant impact on human health and the environment. Recent studies highlight that the exposure to polluted air can increase the incidence of diseases and deteriorate the quality of life. Hence, it is necessary to develop tools for real-time air quality monitoring. For air pollution monitoring a wide range of stationary gas and particulate analysers can be used....
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Design and implementation of an illumination system to mimic skyglow at ecosystem level in a large‐scale lake enclosure facility
PublicationLight pollution is an environmental stressor of global extent that is growing exponentially in area and intensity. Artificial skyglow, a form of light pollution with large range, is hypothesized to have environmental impact at ecosystem level. However, testing the impact of skyglow at large scales and in a controlled fashion under in situ conditions has remained elusive so far. Here we present the first experimental setup to mimic...
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User Mobility’s Influence on System Loss in Off-Body BAN Scenarios
PublicationIn this paper, a measurement campaign for off-body communications in an indoor environment is investigated for a set of on-body antennas. The channel impulse response was measured with the user approaching and departing from an off-body fixed antenna using two user dynamics: standing at fixed positions and walking. The processing of the measurement data allowed to evaluate system loss statistics. Different antenna configurations...
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Mobility’s Influence on System Loss in Off-Body BAN Scenarios
PublicationIn this paper, a measurement campaign for off body communications in an indoor environment is investigated for a set of on-body antennas. The channel impulse response was measured with the user approaching and departing from an off-body fixed antenna using two user dynamics, standing at fixed positions and walking. The processing of the measurement data allowed to evaluate system loss statistics. Different antenna configurations...
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Efficiency limit of excitonic photovoltaic cells under phosphor-based white LED illumination
PublicationThe limit of energy conversion of excitonic photovoltaic cells working under white light illumination generated by phosphor-based LED is analysed using the modified Giebink approach. Particularly, the impact of the optical energy gap and energy loss associated with the excitons dissociation at the heterojunction interface on power conversion efficiency of the device are discussed. From the results of our study it follows that the...
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Three-dimensional mapping for data collected using variable stereo baseline
PublicationThe paper describes a system of 3D mapping of data collected with due regard for variable baseline. This solution constitute an extension to a VisRobot sub-system developed as a subsystem, necessary for implementing the generic idea of using mobile robots to explore an indoor static environment. This subsystem is to acquire stereo images, calculate the depth in the images and construct the sought 3D map. Stereo images are obtained...
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Analysis of a caustic formed by a spherical reflector: Impact of a caustic on architectural acoustics
PublicationFocusing sound in rooms intended for listening to music or speech is an acoustic defect. Design recommendations provide remedial steps to effectively prevent this. However, there is a category of objects of high historical or architectural value in which the sound focus correction is limited or even abandoned. This also applies to indoor or outdoor concert shells, installations for teaching and acoustic presentations, etc. The...
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Conception of interactive information and decision support system for urban and industrial air management
PublicationThis article presents the conception of interactive system for air quality management.