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Search results for: THE PARAMETRIC METHOD WITH CONDITIONS
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Distributed processing in medical, parametric imaging
PublicationArtykuł prezentuje metodę dystrybucji bazującej na JavaSpace do zastosowania w wyznaczaniu obrazów parametrycznych. Zaimplementowano metodologię Compute Server, którą użyto do aktywnej termografii i dynamicznych badań MRI mózgu.
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Images of the Seabed of the Gulf of Gdansk Obtained by Means of the Parametric Sonar
PublicationThe main goal of this paper is to present results of the experimental investigation of the seabed by means of parametric echosounder in the form of chosen images. The phenomena of nonlinear interaction between two parallel beams of high intensity gives as a results very narrow beam of low frequency wave, that enables to penetrate the sea bottom. The first step of our investigations was calibration of all the elements of the measuring...
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Detection of Objects Buried in the Sea Bottom with the Use of Parametric Echosounder
PublicationThe paper contains results of a in situ research main task of which was to detect objects buried, partially or completely, in the sea bottom. Object detecting technologies employing acoustic wave sources based on nonlinear interaction of elastic waves require application of parametric sound sources. Detection of objects buried in the sea bottom with the use of classic hydroacoustic devices such as the sidescan sonar or multibeam...
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Processing data on sea bottom structure obtained by means of the parametric sounding
PublicationThe aim of the paper is to analyze data obtain during sounding of the Gdansk Bay by means of the parametric sonar. The accuracy of the sea bottom structure investigation needs the correct configuration of research equipment and the proper calibration of peripheral devices (GPS, heading sensor, motion sensor MRU-Z and navigation units) which provide necessary data to bathymetrical measurement system enabling its work with whole...
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Processing data on sea bottom structure obtained by means of the parametric sounding
PublicationThe aim of the paper is to analyze data obtained during sounding the Gdansk Bay sea bed by means of the parametric echo-sounder. The accuracy of the sea bottom structure investigation needs correct configuration of research equipment and proper calibration of peripheral devices (GPS, heading sensor, MRU-Z motion sensor and navigation instruments which provide necessary data to bathymetrical measurement system, enabling its work...
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Estimating the parameter of inequality aversion on the basis of a parametric distribution of incomes
PublicationResearch background: In applied welfare economics, the constant relative inequality aversion function is routinely used as the model of a social decisionmaker’s or a society’s preferences over income distributions. This function is entirely determined by the parameter, ε, of inequality aversion. However, there is no authoritative answer to the question of what the range of ε an analyst should select for empirical work. Purpose...
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Parametric optimization of hybrid metalworking machinery quality
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Selected results of the parametric sounding of the Gdansk Bay
PublicationW pracy przedstawiono metodykę i wyniki sondowania dna Zatoki Gdańskiej echosondą parametryczną.
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Synthesis of parametric images in the medical active thermography
PublicationArtykuł przedstawia zastosowanie nowej metody syntezy obrazów w termografii dla potrzeb opisu ilościowego właściwości termicznych tkanek. opis taki umożliwia różnicowanie przypadków medycznych. Metodę zastosowania dla licznych pomiarów fantomowych oraz in vitro. Przedstawiono i omówiono rezultaty prac.
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PROPERTIES OF PARAMETRIC ALGORITHMIC DESIGN OF RESIDENTIAL HOUSES IN URBAN CONTEXT
PublicationDesign explorations of architectural avant-garde resulted in the development of digital techniques that allow solving very complex and demanding contemporary design challenges. In the architectural discourse the new design workshop seems to be symbolized mainly by the projects of sports facilities, cultural, administrative or multifunctional high-rise buildings. However for the quality of society life is more important to exploit...
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Parametric Study on a Performance of a Small Counter-Rotating Wind Turbine
PublicationA small Counter-Rotating Wind Turbine (CRWT) has been proposed and its performancehas been investigated numerically. Results of a parametric study have been presented in this paper.As parameters, the axial distance between rotors and a tip speed ratio of each rotor have been selected.Performance parameters have been compared with reference to a Single Rotor Wind Turbine (SRWT).Simulations were carried out with Computational Fluids...
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A study of the kinetics of bismuth telluride synthesis by an oxide reduction method
PublicationThe kinetics of a reduction of bismuth and tellurium oxides in a hydrogen atmosphere, leading to the formation of thermoelectric bismuth telluride is investigated. The evaluation of the reaction kinetics was based on a thermogravimetric analysis performed in non-isothermal conditions. A non-parametric analysis method and the Friedman method were used for the evaluation of the data. Additionally, for a better understanding of the...
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Usage of parametric echosounder with emphasis on buried object searching.
PublicationThe purpose of this article is to present the results of investigation to search for buried objects. The paper will contain echograms and other means of visualization from buried pipe placed between area of W?adys?awowo and gas platform and interesting in terms of the number of small and medium-sized unidentified objects found in the muddy bottom at different depths localized in the Gulf of Puck - results will be presented also...
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Hyperelastic Microcantilever AFM: Efficient Detection Mechanism Based on Principal Parametric Resonance
PublicationThe impetus of writing this paper is to propose an efficient detection mechanism to scan the surface profile of a micro-sample using cantilever-based atomic force microscopy (AFM), operating in non-contact mode. In order to implement this scheme, the principal parametric resonance characteristics of the resonator are employed, benefiting from the bifurcation-based sensing mechanism. It is assumed that the microcantilever is made...
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Pressure distribution and beam pattern of the parametric acoustic arrays.
PublicationPrzedstawiono model matematyczny i wyniki badań teoretycznych zjawiska oddziaływań fal dla źródeł parametrycznych. Model matematyczny zbudowano w oparciu o równanie KZK. Do rozwiązania zagadnienia zastosowano metodę różnic skończonych. Badano zmiany ciśnienia fal wybranych częstotliwości w obrębie wiązki akustycznej oraz charakterystyki kierunkowe dla kołowych źródeł parametrycznych generujących fale różnych częstotliwości.
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Automatic synthesis of parametric images in dynamic MRI imaging
PublicationArtykuł opisuje automatyczne metody czasu dojścia kontrastu (BAT) i tętniczą funkcję wejścia (AIF). Metody te porównano dla klinicznych i symulacyjnych danych.
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Parametric imaging in dynamic glucose metabolism studies in brain
PublicationArtykuł analizuje badania dynamiczne 18FDG-PET, które służą do estymacji metabolizmu glukozy w mózgu. Zbadano w nim wpływ zakłóceń na wyznaczanie interesującego nas parametru LCMRGlc.
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Parametric analysis of Istanbul's Ring Road viaduct for three levels of seismic load
PublicationThe paper presents a parametric analysis of the Istanbul's ring road viaduct that is currently under construction within the Northern Marmara Highway project. The structure, due to its location on seismic prone areas is exposed to seismic loads of different strengths and different return periods. The study is focused on concrete bridge supports that are design to work in nonlinear range. The parametric study, conducted in MATLAB...
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Parametric optimization of sandwich composite footbridge with U-shaped cross-section
PublicationParametric optimization of sandwich composite footbridge was presented in the paper. Composite footbridge has 14,5 m long and has U-shaped cross-section with inner dimensions 2,6 × 1,3 m. The sandwich structure in made from GFRP laminate as a faces and PET foam as a core. The aim of analysis was to minimize the mass of the new footbridge that can lead to minimize the cost of structure. After optimization was conducted, the new...
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Parametric versus nonparametric modelling of dynamic susceptibility contrast enhanced MRI based data
PublicationDynamic tracking of a bolus of a paramagnetic agent (dynamic susceptibility contract - DSC) in MRI (magnetic resonance imaging) measurements is successfully used for assessment of the tissue perfusion and the other features and functions of the brain (i.e. cerebral blood flow - CBF, cerebral blood volume - CBV, mean transit time - MTT). The parametric and nonparametric approaches to the identification of MRI models are presented...
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A hybrid speech codec employing parametric and perceptual coding techniques
PublicationW referacie przedstawiono hybrydowy kodek mowy dla zastosowan w komunikacji VoIP wykorzystujący kodowanie parametryczne i percetualne. Sygnał mowy jest dzielony na składowe dźwięczne, które podlegają kodowania perceptualnemu, składowe bezdźwięczne, które kodowane są metodą parametryczną oraz transjenty, które nie są kodowane żadną stratną metodą. Dodatkowo przedstawiono architekturę kodeka, w której perceptualnie kodowana i przesyłana...
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Parametric study of radiation from circumferential slots on a conducting cylinder
PublicationBadania numeryczne dotyczące promieniowania z szyku szczelin umieszczonych na powierzchni przewodzącego walca. Zaproponowana została prosta i szybka metoda analizy zjawiska, przy uwzględnieniu efektu sprzężenia pomiędzy szczelinami. Metoda bazuje na transformacji Fouriera sumy pól wypromieniowanych przez każdą ze szczelin. Metodę zweryfikowano poprzez porównanie wyników z wynikami metody pełnofalowej. Zaprezentowano charakterystyki...
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Investigation of Transmit and Receive Characteristics of Laboratory Model for the Parametric Echosounder
PublicationInvestigation and operation of devices based on nonlinear interaction of high-intensity waves have been carried out for several decades. However, it is still a new tool to study the properties of the water environment and especially the upper layers of the seabed. This paper describes the results of tests of the new device that is intended to be applied for sounding underwater areas. The device has been designed and built in collaboration with...
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Acoustic imaging of selected areas of Gdansk Bay with the aid of parametric echosounder and side-scan sonar
PublicationThe article presents and analyses the data recorded during sounding of the Gdansk Bay seabed with the aid of a parametric echosounder and a side-scan sonar. The accuracy of seabed structure examination, as a condition for obtaining valuable results, requires correct configuration of echolocation devices and proper calibration of peripheral devices, such as the survey unit geographical position sensor – GPS, the navigation unit,...
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Geometry Parametric Model Order Reduction with Randomly Generated Projection Bases
PublicationIn this work, a reduced-order model for geometry parameters and fast frequency sweep is proposed. The Finite Element Method is used to solve time-harmonic Maxwell’s equations. Taking into account the electromagnetic field does not arbitrarily vary as a function of frequency and geometry parameters, a low dimension system manifold is identified. Thus, the original Finite Element problem can be approximated by a model of reduced...
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A Mesh Deformation Technique Based on Solid Mechanics for Parametric Analysis of High-Frequency Devices With 3-D FEM
PublicationIn this paper, a versatile technique for mesh defor- mation is discussed, targeted at the electromagnetic (EM) field simulation of high-frequency devices using the 3-D finite element method (FEM). The approach proposed applies a linear elasticity model to compute the displacements of the internal mesh nodes in 3-D when the structure geometry is changed. The technique is compared with an alternative approach...
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Application of decision–making parametric structures in the analysis of a compound planetary gear
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"FEM Parametric Study on Ultimate Bearing Capacity of CFST Arch Bridge
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Impact of an unsecured excavation on an underground pipeline
PublicationThe paper presents a numerical analysis of the impact of an unsecured excavation on an underground pipeline in selected soil conditions. The research was inspired by a real-life failure of a water pipeline which was caused by a nearby unsecured excavation (Sikora et al. 2015). The failure was triggered by displacement of soil mass in the vicinity of the pipeline. The study conducted in the framework of Finite Element...
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Comparison of selected parametric methods for prediction of inland waterways ship hull resistance in towing tank test
PublicationIn the paper selected approximate methods for calculation of inland waterways ship resistance and their verification by towing tests, compared on the example of a small urban ferry, are presented. The test results are made for both the bare hull and the hull with appendages (skeg, azimuthal propeller). Significant differences between results of the theoretical methods and experimental ones, especially in the case of the model with...
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Globalized parametric optimization of microwave components by means of response features and inverse metamodels
PublicationSimulation-based optimization of geometry parameters is an inherent and important stage of microwave design process. To ensure reliability, the optimization process is normally carried out using full-wave electromagnetic (EM) simulation tools, which entails significant computational overhead. This becomes a serious bottleneck especially if global search is required (e.g., design of miniaturized structures, dimension scaling over...
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Non-parametric application of Tsallis statistics to systems consisting of M hydrogen molecules
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Improving signal quality of a speech codec using hybrid perceptual-parametric algorithm
PublicationW artykule zaprezentowano hybrydową architekturę parametryczno-perceptualną kodeka mowy. Jego podstawę stanowi kodek CELP, który wspomagany jest kodekiem perceptualnym. Celem zastosowania proponowanej metody jest uzyskanie poprawy jakości kodowania sygnału mowy. Badaniom poddano dwie architektury, z których w jednej dźwięczne części sygnału rezydualnego kodeka CELP kodowane są perceptualnie. Drugi z proponowanych kodeków dokonuje...
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Trace of Flicker Sources by Using Non-Parametric Statistical Analysis of Voltage Changes
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Brain perfusion imaging with the use of parametric modelling basing on DSC-MRI data
PublicationW pracy do estymacji parametrów perfuzji mózgu: przepływu krwi mózgowej (cerebral blood flow, CBF), objętości krwi mózgowej (cerebral blood volume, CBV) oraz średniego czasu przejścia (mean transit time, MTT) wykorzystano pomiary DSC-MRI (Dynamic Susceptibility Contrast Magnetic Resonance Imaging). W modelowaniu danych MRI zastoswoano model trzykompartmentowy. Przedstawiono i porównano dwa podejścia do identyfikacji modelu różniące...
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Identification of quasi-periodically varying systems using the combined nonparametric/parametric approach
PublicationW artykule przedstawiono tzw. uogólniony periodogram pozawlający na określenie liczby funkcji bazowych opisujących obiekt o parametrach zmieniających się w sposób pseudookresowy. Pokazano w jaki sposób określić wartości początkowe dla algorytmów opartych na metodzie funkcji bazowych na jego podstawie. Skuteczność zaproponowanych metod zilustrowano przykładami.
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Parametric analysis of Istanbul's Ring Road viaduct for three levels of seismic load
PublicationThe paper presents a numerical analysis of the Istanbul's ring road viaduct that is currently under construction within the Northern Marmara Highway project. The structure, due to its location on seismic prone areas is exposed to seismic loads of different magnitude and different return periods. The study is fo-cused on concrete bridge supports that are design to work in nonlinear range. The study, conducted in SOFISTIK environment,...
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Optimal input design using sensitivity criterion for parametric identification of pharmacokinetic models
PublicationPrzedstawiono identyfikację parametryczną kompartmentowych modeli SISO zmiennych stanu systemów farmakokinetycznych. Struktura modelu formułowana jest na podstawie wiedzy a priori. Początkowe estymaty parametrów obliczane są w oparciu o pomiary zgromadzone w eksperymencie intuicyjnym. Na ich podstawie projektowane jest pobudzenie optymalne, które zapewnia najlepszą dokładność estymat parametrów. Przedstawiono optymalizację czułościową...
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Design of Jack-up Platform for 6 MW Wind Turbine: Parametric Analysis Based Dimensioning of Platform Legs
PublicationThe article presents the results of the research conducted within the framework of the project entitled WIND-TU-PLA (ERA-NET, MARTEC II), the general aim of which was to design and analyse supporting structures for wind turbines intended for operation on the South Baltic area. The research part described in the article aimed at developing a preliminary design for a jack-up platform which can operate on water areas with depth of...
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Application of shifted Chebyshev polynomial-based Rayleigh–Ritz method and Navier’s technique for vibration analysis of a functionally graded porous beam embedded in Kerr foundation
PublicationPresent study is dealt with the applicability of shifted Chebyshev polynomial based Rayleigh-Ritz method and Navier’s technique on free vibration of Functionally Graded (FG) beam with uniformly distributed porosity along the thickness of the beam. The material properties such as Young’s modulus, mass density, and Poisson’s ratio are also considered to vary along the thickness of the FG beam as per the power-law exponent model....
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Laboratory investigation with subbottom parametric echosounder SES-2000 standard with an emphasis on reflected pure signals analysis
PublicationThe main goal of the paper is to describe correlations between measurements results of trials taken on Gulf of Gdańsk bottom sounded with parametric echosounder SES-2000 Standard and laboratory research where collected during survey sediments were measured. Stationary tests took place at Gdansk University of Technology where 30 meters long 1.8 meter deep and 3 meters wide water tank is located. Main lobe of antenna was directed...
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The concept of estimation of elevator shaft control measurement results in the local 3D coordinate system.
PublicationGeodetic control measurements play an important part because they provide information about the current state of repair of the construction, which has a direct impact on the safety assessment of its exploitation. Authors in this paper have focused on control measurements of the elevator shaft. The article discusses the problem of determining the deviation of elevator shaft walls from the vertical plane in the local 3D coordinate...
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Parametric impulsive noise detector for corrupted audio signals based on hidden Markow model
PublicationThe paper addresses the problem of impulsive noise detection for audio signals. A structure of threshold parameter detectors using modelingof signals was introduced. the algorithm of the noise detection, based on discrete-time hidden Markow model (HMM)of whitened audio signal is elaborated
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Implementation of Non-Probabilistic Methods for Stability Analysis of Nonlocal Beam with Structural Uncertainties
PublicationIn this study, a non-probabilistic approach based Navier’s Method (NM) and Galerkin Weighted Residual Method (GWRM) in term of double parametric form has been proposed to investigate the buckling behavior of Euler-Bernoulli nonlocal beam under the framework of the Eringen's nonlocal elasticity theory, considering the structural parameters as imprecise or uncertain. The uncertainties in Young’s modulus and diameter of the beam are...
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PARAMETRIC ANALYSIS OF THE EFFICIENCY OF THE COMBINED GAS-STEAM TURBINE UNIT OF A HYBRID CYCLE FOR THE FPSO VESSEL
PublicationA thermal diagram of the combined gas‒steam turbine unit of a hybrid cycle, which is an energy complex consisting of a base gas turbine engine with a steam turbine heat recovery circuit and a steam-injected gas turbine operating with overexpansion, is proposed. A mathematical model of a power plant has been developed, taking into consideration the features of thermodynamic processes of simple, binary, and steam-injected...
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Two-Stage Identification of Locally Stationary Autoregressive Processes and its Application to the Parametric Spectrum Estimation
PublicationThe problem of identification of a nonstationary autoregressive process with unknown, and possibly time-varying, rate of parameter changes, is considered and solved using the parallel estimation approach. The proposed two-stage estimation scheme, which combines the local estimation approach with the basis function one, offers both quantitative and qualitative improvements compared with the currently used single-stage methods.
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Post processing and selecting data obtain with parametric sub-bottom profiler SES-2000 Standard during sounding the Gulf of Gdansk
PublicationThe main goal of the paper is to describe the results of sounding the Gulf of Gdansk seabed using a parametric sub-bottom profiler SES-2000 Standard. Quality of obtained during trials data depends inter alia on proper location of antenna to reduce influence of pitch, roll, heave and ship noise (bubbles from propeller and a hull flow, vibration from main engine and peripheral devices). Furthermore calibration of complementary units...
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Transient response of oscillated carbon nanotubes with an internal and external damping
PublicationThe present works aims at modeling a viscoelastic nanobeam with simple boundary conditions at the two ends with the introduction of the Kelvin-Voigt viscoelasticity in a nonlocal strain gradient theory. The nanobeam lies on the visco-Pasternak matrix in which three characteristic parameters have a prominent role. A refined Timoshenko beam theory is here applied, which is only based on one unknown variable, in accordance with the...
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Parametric study of fluid flow and heat transfer over louvered fins of air heat pump evaporator
PublicationTwo-dimensional numerical investigations of the fluid flow and heat transfer have been carried out for the laminar flow of the louvered fin-plate heat exchanger, designed to work as an air-source heat pump evap- orator. The transferred heat and the pressure drop predicted by simulation have been compared with the corresponding experimental data taken from the literature. Two dimensional analyses of the louvered fins with varying...
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Parametric FE studies on a coupled energetic-statistical size effect in plain concrete beams under bending
PublicationW artykule omówiono wyniki połączonego deterministyczno-statystycznego efektu skali w betonowych belkach podczas zginania. Obliczenia wykonano stosując MES w zakresie sprężysto-plastyczności z nielokalnym osłabieniem. Obliczenia wykonano dla różnych długości korelacji i współczynnika zmienności.