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Wyniki wyszukiwania dla: STATISTICAL APPROACH
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Statistical analysis and robust design of circularly polarized antennas using sequential approximate optimization
PublikacjaIn the paper, reliable yield estimation and tolerance-aware design optimization of circular polarization (CP) antennas is discussed. We exploit auxiliary kriging interpolation models established in the vicinity of the nominal design in order to speed up the process of statistical analysis of the antenna structure at hand. Sequential approximate optimization is then applied to carry out robust design of the antenna, here, oriented...
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APPLICATION OF STATISTICAL FEATURES AND MULTILAYER NEURAL NETWORK TO AUTOMATIC DIAGNOSIS OF ARRHYTHMIA BY ECG SIGNALS
PublikacjaAbnormal electrical activity of heart can produce a cardiac arrhythmia. The electrocardiogram (ECG) is a non-invasive technique which is used as a diagnostic tool for cardiac diseases. Non-stationarity and irregu- larity of heartbeat signal imposes many difficulties to clinicians (e.g., in the case of myocardial infarction arrhythmia). Fortunately, signal processing algorithms can expose hidden information within ECG signal contaminated...
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Verification of Economic and Agricultural Indicators With the Use of Statistical Methods on the Example of Individual Farms
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Ryzyko statystyczne a ryzyko rzeczywistego pacjenta = Statistical risk and risk of the real patient
PublikacjaDzięki wieloletnim obserwacjom populacji ludzkiej udało się zidentyfikować czynniki ryzyka choroby wieńcowej. Najważniejsze z nich to: wiek, płeć, obciążenie genetyczne, palenie papierosów, stężenie cholesterolu we krwi, ciśnienie tętnicze, brak aktywności fizycznej, nadwaga, obecność cukrzycy. Obserwacje prospektywne populacji dostarczyły danych do opracowania modeli, które określają relacje między wartościami czynników ryzyka...
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Trace of Flicker Sources by Using Non-Parametric Statistical Analysis of Voltage Changes
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Statistical description and numerical calculations of cylindrical vertical tanks with initial geometric imperfections
PublikacjaDokonano identyfikacji rzeczywistych wstępnych imperfekcji geometrycznych stalowych pionowych zbiorników walcowych. Imperfekcje przedstawiono jako pole losowe opisane za pomocą odpowiednio dobranej funkcji korelacyjnej, wartości oczekiwanej oraz obwiedni pola. Wykorzystując własne programy numeryczne przeprowadzono generację zbioru odchyłek geometrycznych zbiornika. Porównano estymatory wygenerowanego pola losowego z parametrami...
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Statistical data of hull main parameters useful for preliminary design of SWATH ships
PublikacjaW artykule przedstawiono rezultaty badań dotyczących statystycznych relacji głównych parametrów projektowych kadłuba statków typu SWATH, wykonanych w oparciu o zebrane w literaturze przedmiotu dane o ponad osiemdziesięciu statkach. Zależności statystyczne przedstawiono w postaci histogramów: długości statku L, histogramów wartości stosunków długości do szerokości L/B, długości do wysokości bocznej L/H, długości pływaków do ich...
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Measurements of Two-phase Flows in Pipelines Using Radioisotopes and Statistical Signal Processing
PublikacjaThis paper presents an application of radiotracers and gamma absorption method in two-phase flow measurements in pipelines. Two different methods were implemented to analysis of acquired signals. Investigated methods are based on the cross-correlation function and the phase of the cross-spectral density distribution. The examples presented in the article illustrate the application of the radioisotopes to evaluation of liquid-gas...
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Statistical evaluation of the changes in cellulose properties caused by the stepwise solvent exchange and esterification
PublikacjaThe objective of the research was to empirically confirm the changes in cellulose reactivity caused by the pre-treatment with solvents of different polarity. Therefore, 5 solvents varying in their polar component of surface tension from 0 to 4.6 mN/m were chosen. Their impact on the biopolymer properties was carefully analysed concerning chemical structure, crystallinity and surface characteristics. It was revealed that the length...
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Karhunen-Loeve-based approach to tracking of rapidly fading wireless communication channels
PublikacjaWhen parameters of wireless communication channels vary at a fast rate, simple estimation algorithms, such as weighted least squares (WLS) or least mean squares (LMS) algorithms, cannot estimate them with the accuracy needed to secure the reliable operation of the underlying communication systems. In cases like this, the local basis function (LBF) estimation technique can be used instead, significantly increasing the achievable...
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Evaluation of a Novel Approach to Virtual Bass Synthesis Strategy
PublikacjaThe aim of this paper is to present a novel approach to the Virtual Bass Synthesis (VBS) strategy applied to portable computers. The developed algorithms involve intelligent, rule-based settings of bass synthesis parameters with regard to music genre of an audio excerpt and the type of a portable device in use. The Smart VBS algorithm performs the synthesis based on a nonlinear device (NLD) with artificial controlling synthesis...
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SCRAMBLE’N’GAMBLE: a tool for fast and facile generation of random data for statistical evaluation of QSAR models
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Statistical evaluation of the effectiveness of different extraction techniques for determining robenidyne levels in poultry feed.
PublikacjaPoprzez zastosowanie testu Kruskala-Wallisa i chemometrycznej techniki analizy podobieństwa porównano efektywność sześciu różnych technik ekstrakcji (wytrząsanie, ekstrakcja w aparacie Soxhleta, w aparacie Soxteca, wspomaganej ultradźwiękami, wspomaganej promieniowaniem mikrofalowym oraz przyspieszonej ekstrakcji rozpuszczalnikiem) na podstawie wyników odzysku robenidyny z próbek paszy dla ptaków. W zależności od zastosowanej techniki...
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Optimization of briquetting technology of fine-grained metallurgical materials based on statistical models of compressibility
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Multivariate statistical comparison of analytical procedures for benzene and phenol determination with respect to their environmental impact
PublikacjaThe studydescribesthepossibilityofapplicationofself-organizingmapstechniquetoassessthe greenness ofanalyticalmethodologies.Themetrologicaland “environmentalimpact” parametersof proceduresforbenzeneandphenoldeterminationinwatersamplesweresetsofinputdatafor chemometric analysis.Totally47objectsand8variablesformedthedatausedforanalysis.Themajor factors responsiblefornon-greencharacterofthemethodologyaretheamountoforganicsolventand amount...
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Drawing conclusions about reliability of power systems from small number of statistical data
PublikacjaW artykule podjęto próbę udzielenia odpowiedzi na pytanie, czy możliwe jest wyciągnięcie przydatnych w praktyce wniosków o niezawodności elementów technicznych, wchodzących w skład systemów energetycznych, mając do dyspozycji nieliczne dane statystyczne. W opinii autora jest to możliwe. Wskazano dwie drogi postępowania. Pierwsza opiera się na wykorzystaniu metod statystycznych. Druga wykorzystuje elementy teorii zbiorów rozmytych.
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Furan Fragmentation in the Gas Phase: New Insights from Statistical and Molecular Dynamics Calculations
PublikacjaWe present a complete exploration of the different fragmentation mechanisms of furan (C4H4O) operating at low and high energies. Three different theoretical approaches are combined to determine the structure of all possible reaction intermediates, many of them not described in previous studies, and a large number of pathways involving three types of fundamental elementary mechanisms: isomerization, fragmentation, and H/H2 loss...
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Optimization of Single-Sided Lapping Kinematics Based on Statistical Analysis of Abrasive Particles Trajectories
PublikacjaThe chapter presents the influence of selected kinematic parameters on the geometrical results of the single-sided lapping process. The optimization of these parameters is aimed at improving the quality and flatness of the machined surfaces. The uniformity of tool wear was assumed as main optimization criterion. Lapping plate wear model was created and in detail was analyzed. A Matlab program was designed to simulate the abrasive...
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FE analysis of a coupled energetic-statistical size effect in plain concrete beams with varying material properties.
PublikacjaThe numerical FE investigations of a coupled energetic-statistical size effect in unnotched concrete beams of similar geometry under quasi-static three point bending were performed within elasto-plasticity with non-local softening. The stochastic FE analyses were carried out with three different beam sizes. Deterministic calculations were performed with the uniform distribution of a uniaxial tensile strength. In statistical calculations...
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The Efficiency of Polish Stock Market: Ordinal Patterns Approach
PublikacjaZunino et al. analyzed the problem of discrimination of developed and emergent markets by the use of ordinal patterns methods: number of forbidden patterns and ordinal pattern probability distribution as a basis for entropy and statistical measure of complexity. In this paper we apply the same methodology for the analysis of Polish stock market (index WIG). The results indicate that Polish market belongs neither to developed, nor...
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Application of gamma densitometry and statistical signal analysis to gas phase velocity measurements in pipeline hydrotransport
PublikacjaThe work presents selected methods of signal analysis used in the processing of data obtained from radiometric probes. The used data came from an exemplary study of a two-phase liquid-gas flow at the laboratory installation. In such rigs many possible transport types may be observed, i.e. slug, plug and bubble flow, and each of them gives different signal-to-noise ratio of recorded data. Therefore, available radiometric methods...
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Application of gamma densitometry and statistical signal analysis to gas phase velocity measurements in pipeline hydrotransport
PublikacjaThe work presents selected methods of signal analysis used in the processing of data obtained from radiometric probes. The used data came from an exemplary study of a two-phase liquid-gas flow at the laboratory installation. In such rigs many possible transport types may be observed, i.e. slug, plug and bubble flow, and each of them gives different signal-to-noise ratio of recorded data. Therefore, available radiometric methods...
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Example applications of control charts as a quality tool for statistical process control in a small manufacturing company
PublikacjaPraca zawiera przykład wdrożenia kart kontrolnych w małym zakładzie produkcyjnym zajmującym się wytwarzaniem komponentów z blach. Pokazano jak z zastosowaniem dostępnego pakietu biurowego, można stworzyć statystyczną kontrolę procesu(SPC)w małej firmie. Artykuł zawiera wyniki z przykładowych analizowanych procesów.
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FE-investigations of a deterministic and statistical size effect in granular bodies within a micro-polar hypoplasticity
PublikacjaArtykuł omawia deterministyczny i statystyczny efekt skali w materiałach granulowanych podczas ścinania cienkiej warstwy piasku między dwoma bardzo szorstkimi ścianami. Obliczenia wykonano metodą elementów skończonych na bazie mikropolarnego prawa hipoplastycznego. Przyjęto różne wysokości warstw.
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Deterministic and statistical size effect during shearing of granular layer within a micro-polar hypoplasticity
PublikacjaArtykuł omawia deterministyczny i statystyczny efekt skali w materiałach granulowanych podczas ścinania cienkiej warstwy piasku między dwoma bardzo szorstkimi ścianami. Obliczenia wykonano metodą elementów skończonych na bazie mikropolarnego prawa hipoplastycznego. Przyjęto różne metody redukujące ilość realizacji pól losowych dla początkowego wskaźnika porowatości..
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FE investigations of the effect of fluctuating local tensile strength on coupled energetic-statistical size effect in concrete beams
PublikacjaThe effect of fluctuating local tensile strength on a coupled energetic-statistical size effect in plain concrete beams under bending was numerically investigated. First, the influence of varying autocorrelation length of the random field describing a spatial variation of local tensile strength was studied. Next, the influence of the coefficient of variation of local tensile strength was analyzed. The numerical FE investigations...
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Classifying Emotions in Film Music - A Deep Learning Approach
PublikacjaThe paper presents an application for automatically classifying emotions in film music. A model of emotions is proposed, which is also associated with colors. The model created has nine emotional states, to which colors are assigned according to the color theory in film. Subjective tests are carried out to check the correctness of the assumptions behind the adopted emotion model. For that purpose, a statistical analysis of the...
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Using Statistical Methods to Estimate The Worst Case Response Time of Network Software Running on Indeterministic Hardware Platforms
PublikacjaIn this paper we investigate whether the statistical Worst Case Execution Time (WCET) estimation methods devised for embedded platforms can be successfully applied to find the Worst Case Response Time (WCRT) of a network application running on a complex hardware platform such as a contemporary commercial off-the-shelf (COTS) system. Establishing easy-to-use timing validation techniques is crucial for real-time applications and...
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Motives for Going International and Entry Modes of Family Firms in Poland
PublikacjaThe artucule in the theoretical part focuses on theoretical concepts of firm internationalisation and specifics of internationalisation of FBs, especially their motives for going international. In the empirical part the quqantitative approach is adopted. The results of survey are presented on the sample of 216 firms, including 88 FBs. The statistical analysis is carried out
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Catching-up and club convergence from cross-national perspective. A statistical study for the period 1980-2010
PublikacjaArtykuł o charakterze empirycznym, w którym podjęto analizę konwergencji 101 gospodarek świata pod względem poziomu PKB per capita. Analizę przeprowadzono dla lat 1980-2010. Dodatkowo, w ramach analizy empirycznej, zidentyfikowano tzw. kluby konwergencji ekonomicznej, tj. grupy krajów, które ''zbliżały się'' do siebie pod względem poziomu rozwoju gospodarczego w latach 1980-2010.
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Parametric FE studies on a coupled energetic-statistical size effect in plain concrete beams under bending
PublikacjaW 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.
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The influences of the information and communication technology on the structural changes of Japanese energy sectors from 1985 through 2005: a statistical analysis
PublikacjaThe purpose of this study is to analyse the influences of information and communication technology (ICT) on the structural changes of Japanese energy sectors from 1985-2005. In this study, ICT is represented by two explanatory variables, namely: 1) computers, main parts and accessories; 2) telecommunications equipment. We employ a statistical tool in investigating the influences quantitatively, namely constrained multivariate regression...
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The Presidential Campaign of Małgorzata Kidawa-Błońska in Media Discourse: Analysis Based on Statistical Corpus Analysis and Topic Modelling
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Statistical process control in software project management : a way to transfer single incident-related knowledge into organizational knowledge
PublikacjaZaproponowano statystyczne podejście do procesu kontroli zarządzania projektami informatycznymi. Przedstawiono sposób zamiany wiedzy incydentalnej na wiedzę organizacyjną.
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Statistical optimization of the synthesis of plant-derived fatty acid esters of TMP over homogeneous organometallic tin catalyst
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Sustainable Development and Motivation Opportunities from the Perspective of Women in the Polish Science Sector in the Light of Statistical Data and Surveys
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Adaptive Method for Modeling of Temporal Dependencies between Fields of Vision in Multi-Camera Surveillance Systems
PublikacjaA method of modeling the time of object transition between given pairs of cameras based on the Gaussian Mixture Model (GMM) is proposed in this article. Temporal dependencies modeling is a part of object re-identification based on the multi-camera experimental framework. The previously utilized Expectation-Maximization (EM) approach, requiring setting the number of mixtures arbitrarily as an input parameter, was extended with the...
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A multi‑criteria approach to investigate spatial distribution,sources, and the potential toxicological effect of polycyclic aromatic hydrocarbons (PAHs) in sediments of urban retention tanks
PublikacjaBottom sediments deposited in retention tanks (RTs) located on two urban streams (Oliwski and Strzyza) in the central part of Gdansk (Poland) were analysed for polycyclic aromatic hydrocarbons’ (PAHs) content. PAHs were extracted from samples with methylene chloride, then the extracts were subjected to clean-up applying the solid phase extraction (SPE) method. Quantitative and qualitative determination of 16 PAHs was performed...
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Spatial Differences in the Chemical Composition of Surface Water in the Hornsund Fjord Area: A Statistical Analysis with A Focus on Local Pollution Sources
PublikacjaSurface catchments in Svalbard are sensitive to external pollution, and yet what is frequently considered external contamination may originate from local sources and natural processes. In this work, we analyze the chemical composition of surface waters in the catchments surrounding the Polish Polar Station in Svalbard, Hornsund fjord area. We have pooled unpublished and already published data describing surface water composition...
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Characterization of Defects Inside the Cable Dielectric With Partial Discharge Modeling
PublikacjaThe continuous monitoring of power system devices is an important step toward keeping such capital assets safe. Partial discharge (PD)-based measurement tools provide a reliable and accurate condition assessment of power system insulations. It is very common that voids or cavities exist in every solid dielectric insulation medium. In this article, different voids are modeled and analyzed using an advanced finite element (FE)-based...
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BLOOD PRESSURE ESTIMATION BY MEANS OF A JOINT IMPEDANCE– PHOTOPLETYSMOGRAPHIC METHOD
PublikacjaThe knowledge of patient’s day to day blood pressure changes is invaluable to physicians for both diagnostics and health monitoring reasons. Constant observation of the pressure throughout a day would provide even more valuable clinical information. A convenient non-invasive methods of blood pressure estimation for monitoring purposes are widely proposed. This work shows a statistical approach to...
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Statistical Data Pre-Processing and Time Series Incorporation for High-Efficacy Calibration of Low-Cost NO2 Sensor Using Machine Learning
PublikacjaAir pollution stands as a significant modern-day challenge impacting life quality, the environment, and the economy. It comprises various pollutants like gases, particulate matter, biological molecules, and more, stemming from sources such as vehicle emissions, industrial operations, agriculture, and natural events. Nitrogen dioxide (NO2), among these harmful gases, is notably prevalent in densely populated urban regions. Given...
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Airfoil Design Under Uncertainty Using Non-Intrusive Polynomial Chaos Theory and Utility Functions
PublikacjaFast and accurate airfoil design under uncertainty using non-intrusive polynomial chaos (NIPC) expansions and utility functions is proposed. The NIPC expansions provide a means to efficiently and accurately compute statistical information for a given set of input variables with associated probability distribution. Utility functions provide a way to rigorously formulate the design problem. In this work, these two methods are integrated...
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Fiscal decentralization in the European Countries: a cluster analysis approach
PublikacjaThe scope of public authority depend on many factors. One of them is a declaration, usually expressed in the constitution of a given country (Sferlea, 2014, Libman, 2010, Nehmelman, Vetzo, 2016) of the application of the decentralisation principle in the performance of public tasks. Despite this declaration, the structure of the public sector and the tasks carried out at different levels in particular countries are not identical....
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A probabilistic-driven framework for enhanced corrosion estimation of ship structural components
PublikacjaThe work proposes a probabilistic-driven framework for enhanced corrosion estimation of ship structural components using Bayesian inference and limited measurement data. The new approach for modelling measurement uncertainty is proposed based on the results of previous corrosion tests that incorporate the non-uniform character of the corroded surface of structural components. The proposed framework's basic features are outlined,...
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Statistical radii associated with amino acids to determine the contact map: fixing the structure of a type I cohesin domain in theClostridium thermocellumcellulosome
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FE calculations of a deterministic and statistical size effect in concrete under bending within stochastic elasto-plasticity and non-local softening
PublikacjaW artykule przedstawiony wyniki obliczeń MES deterministycznego i statystycznego efektu skali w belkach betonowych podczas zginania. Zastosowano model w ramach stochastycznej sprężysto-plastyczności i nielokalnego osłabienia. Belki były geometrycznie podobne. Wyniki porównano z modelem efektu skali Bazanta.
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Extensions of ETSI performance measurements methodology for statistical results analysis =Rozszerzenia metodologii pomiarów wydajności zaproponowanej przez ETSI przy statystycznej analizy wyników
PublikacjaNext Generation Network (NGN) architecture was proposed by International Telecommunication Union Telecommunication Standardization Sector (ITU-T) to deliver telecommunication services satisfying the needs of modern society for an access to information. The core of NGN service stratum are IP Multimedia Subsystem (IMS) elements acting as service controls units. To assess performance of IMS components, European Telecommunications...
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Польские словари с русским языком как лингводидактический инструмент (статистический аспект) [Polish dictionaries of the Russian language as a linguodidactic tool (statistical aspect)]
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Continuous blood pressure monitoring by photoplethysmography - signal preprocessing requirements based on blood flow modelling
PublikacjaObjective. The aim of the study is to investigate the effect of the signal sampling frequency and low-pass filtering on the accuracy of the localisation of the fiducial points of the photoplethysmographic signal (PPG), and thus on the estimation of the blood pressure (i.e. the accuracy of the estimation). Approach. Statistical analysis was performed on 3,799 data samples taken from a publicly available database. Four PPGfiducial...