Search
Filters
total: 677
filtered: 470
Search results for: SPECTRUM
-
Spectrum Sensing Based on Hybrid Spectrum Handoff in Cognitive Radio Networks
PublicationThe rapid advancement of wireless communication combined with insufficient spectrum exploitation opens the door for the expansion of novel wireless services. Cognitive radio network (CRN) technology makes it possible to periodically access the open spectrum bands, which in turn improves the effectiveness of CRNs. Spectrum sensing (SS), which allows unauthorized users to locate open spectrum bands, plays a fundamental part in CRNs....
-
Lamp of adjustable spectrum for photographic usage
PublicationPhotography is a unique rapidly growing interdisciplinary field encompassing aspects of science, art and technology. Expectations of photographers are steadily increasing with the development of technology. One of the areas playing a crucial role in photography is lighting. Consequently, several types of light sources for photographic use have been developed. The ongoing research in this field concentrates on lamps with tunable...
-
Isotope shifts in the spectrum of Pb I
Publication -
The problem of “spectrum leakage” in the measurement of harmonics
Publication -
Analysis of Satellite Compass Error’s Spectrum
Publication -
Direct spectrum detection based on Bayesian approach
PublicationThe paper investigates the Bayesian framework's performance for a direct detection of spectrum parameters from the compressive measurements. The reconstruction signal stage is eliminated in by the Bayesian Compressive Sensing algorithm, which causes that the computational complexity and processing time are extremely reduced. The computational efficiency of the presented procedure is significantly...
-
Ab Initio Study of the Electronic Spectrum of 7-Hydroxyquinoline
PublicationThe electronic spectrum of 7-hydroxyquinoline has been studied by using ab initio Multi-State Multi-Reference Møller-Plesset Second-Order Perturbation Theory (MSMRMP2). The energy range up to 6.5 eV is taken into consideration. The lowest π–π* transition is calculated to have an energy of 3.65 eV in good agreement with experimental data. Several other π–π* transitions are predicted to have excitation energies of 4.93, 5.20, 5.47,...
-
Stress Monitoring System for Individuals with Autism Spectrum Disorders
PublicationIn this article, a stress monitoring system tailored for individuals with Autism Spectrum Disorders (ASD) and developed for the educational institution is presented. People with ASD face problems with effective stress management due to their high self-perceived levels of stress, poor ability to cope with it, and dificulties with the accurate detection of the source of stress. Consistently, being able to measure stress appears to...
-
Behaviometrics of Digital Games for Children with Autism Spectrum Disorder
PublicationTe paper reports current stage of the project Automated Terapy Monitoring for Children with Developmental Disorders of Autism Spectrum (AUTMON), that aims at development of methods and tools to allow for the automatic evaluation of the therapy progress among children with autism. Finding objective measures suitable for evaluating therapy progress would let create a system supporting those who diagnose autism and the therapists...
-
Pounding force response spectrum under earthquake excitation
PublicationW artykule przedstawiono możliwość wykorzystania spektrum siły zderzenia jako zaproponowanego przez autora narzędzia pomocnego przy projektowaniu budynków narażonych na zderzenia podczas trzęsień ziemi. Przedstawione wykresy spektrów pokazały, iż właściwy dobór parametrów budowli, takich jak szerokość przerwy pomiędzy budynkami, okres drgań własnych konstrukcji, liczba tłumienia, masa, współczynnik ciągliwości, czy też przesunięcie...
-
Influence of local electron interactions on phonon spectrum in iron
Publication -
On autoregressive spectrum estimation using the model averaging technique
PublicationThe problem of estimating spectral density of a nonstationary process satisfying local stationarity conditions is considered. The proposed solution is a two step procedure based on local autoregressive (AR) modeling. In the first step Bayesian-like averaging of AR models, differing in order, is performed. The main contribution of the paper is development of a new final-prediction-error-like statistic, which can be used to select...
-
FFT spectrum based matching algorithm for activedynamic thermography
PublicationIn Active Dynamic thermography (ADT) sequences of consecutive temperature distributions are analyzed. In biomedical applications of ADT, the problems of a patient's movements in front of a thermal camera should be eliminated before data analysis. Complete mechanical stabilization of the patients is impossible due to natural voluntary and involuntary moves caused by pulse breathing, etc. This paper presents a simple and efficient...
-
Matrix representation of the ARMA(p, q) process spectrum
PublicationPraca dotyczy szeregów czasowych i ich modelowania scałkowanymi procesami autoregresji i średniej ruchomej ARIMA(p,q). Dla dowolnych parametru modelu p i q, zaproponowano opis spektrum wykorzystując zapis macierzowy. Takie podejście pozwoliło na znaczne uproszczenia przy różnego rodzaju wyprowadzeniach, a w efekcie i obliczeniach.
-
Uncertainty in measuring the power spectrum density of a random signal
PublicationPrzedstawiono sposób oszacowania niepewności wyznaczania gęstości widmowej mocy przebiegu losowego. Przeprowadzono ocenę niepewności estymacji gęstości widmowej mocy biorąc pod uwagę propagację niepewności związanej z rejestracją pojedynczej próbki sygnału w algorytmie cyfrowego przetwarzania sygnału oraz błąd obciążenia estymatora wynikający z zastosowanego modelu matematycznego wielkości wyznaczanej. Wyprowadzono zależności na...
-
Efficiency of IEEE 802.15.4a UWB Impulse Radio Spectrum Shaping
PublicationThis paper presents results of impulse radio signal spectrum shaping efficiency investigations. Basic parameters of IEEE 802.15.4a UWB signal and outline of proposed spectrum shaping methods are briefly described. The main part of the paper presents influence of signal and algorithms parameters on the results of spectrum shaping.
-
Application of IR UWB Spectrum Shaping to IEEE 802.15.4a Standard
PublicationCoexistence of existing narrowband systems and new ultra wideband devices in the same frequency range requires using some interference mitigation techniques, for example based on spectrum shaping. This paper presents efficiency of impulse radio spectrum shaping methods, applied to IEEE 802.15.4a UWB alternate physical layer signals. Basic parameters of 802.15.4a signal structure and outline of proposed spectrum shaping methods...
-
Analytical studies of spectrum broadcast structures in quantum Brownian motion
PublicationSpectrum broadcast structures are a new and fresh concept in the quantum-to-classical transition, introduced recently in the context of decoherence and the appearance of objective features in quantum mechanics. These are specific quantum state structures, responsible for the objectivization of the decohered state of a system. Recently, they have been demonstrated by means of the well-known quantum Brownian motion model of the recoilless...
-
Detection of the Direct Sequence Spread Spectrum Signals with BPSK Modulation
PublicationThis paper presents a method of the DS CDMA signals with BPSK modulation detection through the examination of the enhanced signal spectrum density. On the base of experiments carried out on the real radio communication signals the impact of a narrowband emission occurring in the examined frequency band on the detection process effectiveness was shown. The results of the experiment aimed at the detection of the satellite navigation...
-
The influence of intermolecular correlations on the infrared spectrum of liquid dimethyl sulfoxide
PublicationDimethyl sulfoxide (DMSO) is routinely applied as an excellent, water-miscible solvent and chemical reagent. Some of the most important data concerning its liquid structure were obtained using infrared (IR) spectroscopy. However, the actual extent of intermolecular correlations that connect the isolated monomer spectrum to the IR response of the bulk liquid is poorly studied thus far. Using ab initio molecular dynamics (AIMD) simulations,...
-
On adaptive covariance and spectrum estimation of locally stationary multivariate processes
PublicationWhen estimating the correlation/spectral structure of a locally stationary process, one has to make two important decisions. First, one should choose the so-called estimation bandwidth, inversely proportional to the effective width of the local analysis window, in the way that complies with the degree of signal nonstationarity. Too small bandwidth may result in an excessive estimation bias, while too large bandwidth may cause excessive...
-
The optimized Rayleigh–Ritz scheme for determining the quantum-mechanical spectrum
Publication -
The Effect of the Phenomenon of “Spectrum Leakage” on the Measurement of Power Quality Parameters
Publication -
Supply current spectrum estimation of digital cores at early design
PublicationPrzedstawiono nową aproksymacyjną metodę obliczania widma prądu zasilania układów cyfrowych. Metoda oparta jest na charakterystyce impulsów prądowych w kategoriach ich czasu narastania, opadania i długości impulsu. Górną granicę widma (obwiednię) można obliczyć posługując się gęstością prawdopodobieństwa zmian stanu sygnałów w węzłach układu cyfrowego. W odróżnieniu od znanych metod, metoda proponowana wykorzystuje ograniczoną...
-
Spectrum-based modal parameters identification with Particle Swarm Optimization
PublicationThe paper presents the new method of the natural frequencies and damping identification based on the Artificial Intelligence (AI) Particle Swarm Optimization (PSO) algorithm. The identification is performed in the frequency domain. The algorithm performs two PSO-based steps and introduces some modifications in order to achieve quick convergence and low estimation error of the identified parameters’ values for multi-mode systems....
-
On Adaptive Spectrum Estimation of Multivariate Autoregressive Locally Stationary Processes
PublicationAutoregressive modeling is a widespread parametricspectrum estimation method. It is well known that, in the caseof stationary processes with unknown order, its accuracy canbe improved by averaging models of different complexity usingsuitably chosen weights. The paper proposes an extension of thistechnique to the case of multivariate locally stationary processes.The proposed solution is based on local autoregressive...
-
Simulations of impact force spectrum for earthquake-induced structural pounding.
PublicationCelem artykułu jest analiza możliwości zastosowanie tzw. spektrum siły zderzenia przy projektowaniu sąsiadujących ze sobą konstrukcji budowlanych na terenach sejsmicznych, w przypadku zbyt małej przerwy dylatacyjnej między nimi. W artykule przedstawiono wyniki symulacji numerycznych przeprowadzonych dla różnych wartości parametrów dynamicznych konstrukcji.
-
New method of IEEE 802.15.4a UWB Impulse Radio Spectrum Shaping
PublicationThis paper presents a new technique of IEEE 802.15.4a ultra-wideband signal spectrum control, based on changes in sequences of transmitted pulses with very short duration time. Basic parameters of UWB signal and outline of proposed spectrum shaping methods are briefly described. The main part of the paper presents influence of signal and algorithms parameters on the results of spectrum shaping.
-
IEEE 802.15.4a Impulse Radio Spectrum Shaping by Changes in Pulse Sequence
PublicationThis paper presents one of possible techniques of IEEE 802.15.4a ultra-wideband signal spectrum control, based on changes in sequences of transmitted pulses with very short duration time. This technique can reduce probability of mutual interferences between new ultra-wideband and existing narrowband devices, which may be helpful in further studies on allowing UWB transmission in wider range of spectrum in theEuropean Union.
-
Investigation on accelerated impedance spectrum measurement method with multisine signal stimulation
PublicationThe paper presents an investigation on the accelerated impedance spectrum measurement method, oriented at parameter identification of technical objects modelled by a linear equivalent circuit, e.g. anticorrosion coatings.The method is based on multisine signal stimulation of an object and response analysis by triangle window filterbanks.It has several advantages, as compared with conventional point-by-point spectrum measurement....
-
Ground-based, Hyperbolic Radiolocation System with Spread Spectrum Signal - AEGIR
PublicationThe most popular radiolocation systems in the world (at present), is the American GPS (Global Positioning System). It is managed by the Department of Defense and there is always the possibility of the occasional inaccuracies or deliberate introduction of errors that prevent its use by the special services or armies of other countries than the U.S.A. This situation has spawned the need to develop an autonomous, ground-based radiolocation...
-
Employees With Autism Spectrum Disorders in the Digitized Work Environment: Perspectives for the Future
PublicationThe aim of this article is to examine the opportunities for employees with autism spectrum disorders (ASDs), arising from digital technology (DT) development. The author discusses assistive technology (AT) as a mean of creating a better work environment, making the digitized workplace more friendly for people with ASD. A possible solution of communication problems is replacing the interpersonal communication between employees with...
-
Multifractal estimates of monofractality in RR-heart series in power spectrum ranges
Publication -
“Evolution of ‘Dementia Infantilis to Childhood disintegrative Disorder, or Autism Spectrum Disorder”
Publication -
Stochastic model of the load spectrum for main engines of sea-going ships
PublicationW artykule przedstawiono możliwość zastosowania procesów semimarkowskich do probabilistycznego opisu widma obciążeń silników o zapłonie samoczynnym, zastosowanych do napędu statków - czyli silników głównych. W rozważaniach uwzględnione zostały charakterystyki zewnętrzne mocy tego rodzaju silników. Umożliwiły one sformułowanie czteroelementowego zbioru stanów procesu obciążeń tego rodzaju silników. Do opisu rzeczywistego procesu...
-
The Role of Dopaminergic Genes in Probabilistic Reinforcement Learning in Schizophrenia Spectrum Disorders
Publication -
Confirmation Bias in the Course of Instructed Reinforcement Learning in Schizophrenia-Spectrum Disorders
Publication -
The Combination of Beta-Blockers and ACE Inhibitors Across the Spectrum of Cardiovascular Diseases
Publication -
Efficiency of exciton splitting in organic photovoltaic cells within EQE spectrum
PublicationThe paper presents a procedure of estimating the efficiency of exciton splitting at ED/EA interface. The procedure consists in evaluation of splitting of excitons into electron-hole pairs on the basis of the external quantum efficiency spectra of planar cells and spectra of absorbance of active organic layers. The fitting parameters are the exciton splitting probabilities at ED/EA interface. The presented procedure was applied...
-
Impact force spectrum for damage assessment of earthquake-induced structural pounding
PublicationCelem artykułu jest zastosowanie spektrum siły zderzenia do szacowania zniszczeń powstałych na skutek zderzeń pomiędzy konstrukcjami budowlanymi, do których dochodzi podczas trzęsień ziemi. Wyniki analizy wskazują, iż spektrum takie może być przydatnym narzędziem przy projektowaniu konstrukcji podatnych na zderzenia. Przykłady spektrów odpowiedzi pokazują, iż zapewnienie odpowiedniej przerwy dylatacyjnej lub zgranie parametrów...
-
Improving the accuracy of bearing in active sonar with cylindrical array using spectrum estimation.
PublicationThe articles presents a method for improving the accuracy of bearing in multibeam sonar with a cylindrical array. Based on a known spatial spectrum estimation technique, the method has been successfully used in linear array systems. Its accuracy of bearing is satisfactory and ensures a relatively low computational effort. The article discusses certain simplifications and assumptions to adapt the spatial spectrum estimation technique...
-
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...
-
Inclusive Communication Model Supporting the Employment Cycle of Individuals with Autism Spectrum Disorders
PublicationDifficulties with interpersonal communication experienced by individuals with autism spectrum disorders (ASD) significantly contribute to their underrepresentation in the workforce as well as problems experienced while in employment. Consistently, it is vital to understand how communication within the employment cycle of this group can be improved. This study aims to identify and analyze the possibilities of modifying the communication...
-
Context of Digitalized Employment for Older Adults with Autism Spectrum Disorder in the New Normal
PublicationEmployers are actively considering how to normalize remote work technology across different industries. The residual risk of coronavirus disease-19 (COVID-19) will necessarily lower the bar for allowing some workers to stay remote on a more permanent basis. This is based on the realization that many essential jobs can be teleworked while retaining or enhancing productivity. The decisions employers make regarding future work arrangements...
-
Robot-Based Intervention for Children With Autism Spectrum Disorder: A Systematic Literature Review
PublicationChildren with autism spectrum disorder (ASD) have deficits in the socio-communicative domain and frequently face severe difficulties in the recognition and expression of emotions. Existing literature suggested that children with ASD benefit from robot-based interventions. However, studies varied considerably in participant characteristics, applied robots, and trained skills. Here, we reviewed robot-based interventions targeting...
-
Spectrum of Bacterial Pathogens from Urinary Infections Associated with Struvite and Metabolic Stones
Publication -
<title>Spectrum analysis of measuring signals in sensor circuits with frequency outputs</title>
Publication -
Application of Pierson-Moskowitz wave spectrum to solution differential equations of multihull vessel
PublicationMotion of a dynamic system can be generated by different external or internal factors. At mathematical modelling external excitation factors of the most significant effect on the system, are selected. Such external factors are usually called excitations. Response of the system to given excitations is mathematically characterized by a definite transformation called operator of a system. For a broad class of dynamic systems the...
-
From limits of quantum operations to multicopy entanglement witnesses and state spectrum estimation.
PublicationBadano ograniczenia na nieliniowe transformacje stanu kwantowego. Wprowadzono strukturalne fizyczne przybliżenia niefizycznych odwzorowań liniowych.Zdefiniowano świadków splątania działających na wielu kopiach danego stanu.Pokazano zastosowanie obserwabli kwantowych w detekcji entropii Tsallisa.
-
Accelerated impedance spectrum measurement via multisine perturbationand digital filter banks
PublicationPrzedstawiono przyspieszoną metodę pomiaru widma impedancyjnego, zorientowaną na pomiary jakości powłok przeciwkorozyjnych, modelowanych liniowymi obwodami zastępczymi. Metoda polega na pobudzeniu układu wielosinusoidalnym sygnałem popudzającym oraz analizie pobudzenia i odpowiedzi obiektu przez bank filtrów cyfrowych. Przedstawiono podstawy teoretyczne metody oraz propozycję metodologii pomiaru. Przeanalizowano wyniki symulacji...