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EN
This paper presents a preliminary study delving into the application of machine learning-based methods for optimizing parameter selection in filtering techniques. The authors focus on exploring the efficacy of two prominent filtering methods: smoothing and cascade filters, known for their profound impact on enhancing the quality of brain signals. The study specifically examines signals acquired through functional near-infrared spectroscopy (fNIRS), a noninvasive neuroimaging modality offering valuable insights into brain activity. Through meticulous analysis, the research underscores the potential of machine learning approaches in discerning optimal parameters for filtering, thereby leading to a significant enhancement in the quality and reliability of fNIRS-derived signals. The results demonstrate the effectiveness of machine learning-based methods in optimizing parameter selection for filtering techniques, particularly in the context of fNIRS signals. By leveraging these approaches, the study achieves notable improvements in the quality and reliability of brain signal data. This work sheds light on promising avenues for refining neuroimaging methodologies and advancing the field of signal processing in neuroscience. The successful application of machine learning-based techniques highlights their potential for optimizing neuroimaging data processing, ultimately contributing to a deeper understanding of brain function.
EN
Parametric results describing the geometric structure of a surface are influenced by many factors. One of the most important is the correct preparation of input data. This is related to the type of Surface levelling, the selection of a suitable measuring section or the applied filtration. The data preparation procedure depends on the adopted measurement technique: contact or optical. Depending on the type of data acquisition, it is necessary to implement supplementary procedures. Each of the applied operations on data directly influences the obtained values of individual spatial parameters 3D and surface parameters 2D, such as roughness, waviness or base profile. In this paper, different surface levelling options and selected filtering methods were analysed. In the case of optical measurements, the influence of filling in non-measured points was also considered. The results obtained allowed us to develop of a data preparation procedure and to determine the influence of the different steps on representative parametric values. It was found that the most significant factor influencing the parameter values obtained is the removal of outliers. In this study, based on two measurement techniques: contact and optical, a procedure for sequential processing of input data was prepared to assess the impact of the steps performed on the resulting values of parameters describing the surface structure. The procedure is based on one of two main types of surface levelling: levelling with the least squares plane (LS) and levelling line by line (LbL), along with the impact of one filtering method – removal of outliers (RO). In the case of optical measurements, the impact of filling unmeasured points (NM) was also considered. It was found that the most significant factor affecting the obtained parameter values is the removal of outliers (RO). The relative differences between the data for which this operation was not applied are 13 % for contact profilometry and approximately 1% for optical profilometry. On the other hand, the procedure of filling unmeasured points (NM) has the least impact – however, this is only applicable in the case of optical measurement techniques. The choice of the appropriate levelling method can affect the final results. Differences between these methods are generally small (up to 5 %), but in certain situations, they can be significant. The obtained results allowed for the development of a data preparation procedure and determining the impact of various stages on the representative parametric values.
EN
Infrared detectors are usually characterized by 1/f noise when operating with biasing. This type of noise significantly reduces detection capabilities for low-level and slow signals. There are a few methods to reduce the influence of 1/f noise, like filtering or chopper stabilization with lock-in. Using the first one, a simple 1st-order analog low-pass filter built-in amplifier usually cuts off 1/f noise fluctuations at low frequencies. In comparison, the stabilization technique modulates the signal transposing to a higher frequency with no 1/f noise and then demodulates it back (lock-in amplifiers). However, the flexible tuned device, which can work precisely at low frequencies, is especially desirable in some applications, e.g., optical spectroscopy or interferometry. The paper describes a proof-of-concept of an IR detection module with an adjustable digital filter taking advantage of finite impulse response type. It is based on the high-resolution analog-to-digital converter, field-programmable gate array, and digital-to-analog converter. A microcontroller with an implemented user interface ensures control of such a prepared filtering path. The module is a separate component with the possibility of customization and can be used in experiments or applications in which the reduction of noises and unexpected interferences is needed.
EN
This study investigates and filters harmonics currents generated by a hybrid system with a storage system (photovoltaic-wind-battery) for Household Applications. In this paper, we prefer to use passive filtering to mitigate the harmonic’s currents especially the passive tuned filter (single and multiple). This method is the most used because it's cheap and effective. The hybrid system studied is used for power supply household applications. This modern system can improve efficiency, reliability, and security while reducing operating costs and offering flexibility. For better working for our system, we use two commands called maximum power point tracking command (MPPT); one for photovoltaic panels, and the second for the wind system, the pulse width modulation control (PWM) for the inverter, and for the control the battery we apply a DC/DC buck-boost. The simulation results obtained with filtering show the improvement of current waveforms and acceptable values of total harmonic distortion (THD).
PL
Niniejsze badanie koncentruje się na badaniu i filtrowaniu prądów harmonicznych generowanych przez system hybrydowy z systemem magazynowania (bateria fotowoltaiczna-wiatrowa) do zastosowań domowych. W tym artykule wolimy stosować filtrowanie pasywne do łagodzenia prądów harmonicznych, zwłaszcza pasywny filtr strojony (pojedynczy i wielokrotny). Ta metoda jest najczęściej używana, ponieważ jest tania i skuteczna. Badany system hybrydowy jest wykorzystywany do zasilania w gospodarstwach domowych. Ten nowoczesny system może poprawić wydajność, niezawodność i bezpieczeństwo przy jednoczesnym obniżeniu kosztów operacyjnych i zapewnieniu elastyczności. Aby lepiej pracować dla naszego systemu, używamy dwóch poleceń zwanych poleceniem śledzenia maksymalnego punktu mocy (MPPT); jeden do paneli fotowoltaicznych, a drugi do systemu wiatrowego, sterowanie modulacją szerokości impulsu (PWM) dla falownika, a do sterowania akumulatorem stosujemy buck-boost DC/DC. Wyniki symulacji uzyskane z filtrowaniem wskazują na poprawę przebiegów prądowych oraz akceptowalne wartości całkowitego zniekształcenia harmonicznego (THD).
EN
The paper presents investigations concerning the decision rule filtering process controlled by the estimated relevance of available attributes. In the conducted study, two search directions were used, sequential forward selection and sequential backward elimination, applied after the knowledge discovery step to the rule sets inferred from a dataset. The steps of sequential search, along with two different strategies of rule selection, were governed by three rankings obtained for variables, all related to characteristics of data and rules that can be induced, as follows, (i) a ranking based on the weighting factor referring to the occurrence of attributes in generated decision reducts, (ii) the OneR ranking exploiting short rule properties, and (iii) the proposed ranking defined through the operation of greedy algorithm for rule induction. The three rankings were confronted and compared from the perspective of their usefulness for the selection of rules performed in the two directions. The resulting sets of rules were analysed with respect to the properties of the constituent decision rules and from the point of performance for all constructed rule-based classifiers. Substantial experiments were carried out in the stylometric domain, treating the task of authorship attribution as classification. The results obtained indicate that for all three rankings and search paths it was possible to obtain a noticeable reduction of attributes while at least maintaining the power of inducers, at the same time improving characteristics of rule sets.
6
Content available remote Emotion-Based Literature Books Recommender Systems
EN
In this paper we propose two book recommendation methods based on emotions extracted from user reviews, using content-based filtering and collaborative filtering. The methods were experimentally evaluated on our own dataset that we collected from Goodreads -- a popular website with large database of books and readers reviews. We created an experimental setup where the recommendation algorithms for carrying out the evaluation using two proposed evaluation metrics: coverage and average recommendations similarity.
PL
W czerwcu 2020 roku, po blisko trzymiesięcznej przerwie spowodowanej pandemią COVID-19, swoją pracę wznowiła stacja naukowo-badawcza zlokalizowana w Oczyszczalni Ścieków Jeleń Dąb w Jaworznie. Jej głównym celem i założeniem jest ozonowanie ścieków oczyszczonych z zamiarem redukcji z nich farmaceutyków na poziomie 80-90%, przy całkowitym braku powstawania substancji kancerogennych. Chodzi o bezpieczne rozkładanie farmaceutyków do związków nieaktywnych. Dzięki temu do środowiska naturalnego wprowadzane zostają oczyszczone ścieki, które będą bezpieczne dla środowiska wodnego. To pierwsza tego typu stacja oraz projekt badawczy w Polsce.
EN
This paper proposes a deep learning approach to recognize Tamil Letter from images which contains text. This is recognition process, the text in the images are divided to letter or characters. Each recognized letters are sending to recognition system and filter the text using deep learning algorithms. Our proposed algorithm is used to separate letter from the text using convolution neural network approach. The filtering system is used for identifying font based on that letters are found. The Tamil letters are test data and loaded in recognition systems. The trained data are input which contains filtered letter from image. For example, Tamil letters such as are available in test dataset. The trained data are applied into deep convolution neural network process. The two dataset are created which contains test data with Tamil letter and second one for recognized input data or trained data. 15 thousands of letters are taken and 512 X 512 X 3 size deep convolution network is created with font and letters. As the result, 85% Tamil letters are recognized and 82% are tested using font. TensorFlow is used for testing the accuracy and success rate.
EN
In this paper various smoothing filters were applied in order to smooth inverted pendulum’s movement trajectory. The filtering was implemented for the purpose of some artifacts removal. The authors tested various classical smoothing filters on the single-inverted pendulum, which is a classical problem in control theory and is widely used for the purpose for testing various control algorithms, neural networks, fuzzy control, genetic algorithms etc.
PL
W niniejszym artykule zastosowano filtry wygładzające w celu wygładzenia trajektorii ruchu odwróconego wahadła. Filtracja została użyta do usunięcia zakłóceń . Autorzy przetestowali różne klasyczne filtry wygładzające na wahadle odwróconym, który jest klasycznym problemem w teorii sterowania i ma szerokie zastosowanie do testów różnych algorytmów, sieci neuronowych, w logice rozmytej, algorytmach genetycznych itp.
EN
A fast phase reconstruction method (FPRM) employing a free-sample hologram can improve the efficiency of phase reconstruction in off-axis digital holography. However, the space-bandwidth product is still confined by spectrum aliasing in the hologram owing to the zero-order term. In this paper, we propose an FPRM that features an efficient zero-order term suppression method called the average gray that can eliminate spectrum shifting. We can implement phase reconstruction by considering both speed and the space-bandwidth product. We verified the validity of our approach for off-axis digital holography using laser and white-light illumination.
EN
In this paper, we show that signal sampling operation can be considered as a kind of all-pass filtering in the time domain, when the Nyquist frequency is larger or equal to the maximal frequency in the spectrum of a signal sampled. We demonstrate that this seemingly obvious observation has wide-ranging implications. They are discussed here in detail. Furthermore, we discuss also signal shaping effects that occur in the case of signal under-sampling. That is, when the Nyquist frequency is smaller than the maximal frequency in the spectrum of a signal sampled. Further, we explain the mechanism of a specific signal distortion that arises under these circumstances. We call it the signal shaping, not the signal aliasing, because of many reasons discussed throughout this paper. Mainly however because of the fact that the operation behind it, called also the signal shaping here, is not a filtering in a usual sense. And, it is shown that this kind of shaping depends upon the sampling phase. Furthermore, formulated in other words, this operation can be viewed as a one which shapes the signal and performs the low-pass filtering of it at the same time. Also, an interesting relation connecting the Fourier transform of a signal filtered with the use of an ideal low-pass filter having the cut frequency lying in the region of under-sampling with the Fourier transforms of its two under-sampled versions is derived. This relation is presented in the time domain, too.
EN
The paper presents a method of obtaining short-term positioning accuracy based on micro electro-mechanical system (MEMS) sensors and analysis of the results. A high-accuracy and fast-positioning algorithm must be included due to the high risk of accidents in cities in the future, especially when autonomous objects are taken into account. High-level positioning systems should consider a number of sub-systems such as global positioning system (GPS), CCTV – video analysis, a system based on analysis of signal strength of access points (AP), etc. Short-term positioning means that there are other locating systems with a sufficiently high degree of accuracy based on, e.g. a video camera, but the located object can disappear when it is hidden by other objects, e.g. people, things, shelves etc. In such a case, MEMS sensors can be employed as a positioning system. The paper examines typical movement profiles of a radio-controlled (RC) model and fundamental filtering methods in respect of position accuracy. The authors evaluate the complexity and delay of the filter and the accuracy of the positioning in respect of the current speed and phase of movement (positive acceleration, constant) of the object. It is necessary to know whether and how the length of the filter changes the position accuracy. It has been shown that the use of fundamental filters, which provide solutions in a short time, enables to locate objects with a small error in a limited time.
EN
This paper presents a geomagnetic detection method for pipeline defects using complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) and wavelet energy product (WEP) - Teager energy operator (TEO), which improves detection accuracy and defect identification ability as encountering strong inference noise. The measured signal is first subtly decomposed via CEEMDAN into a series of intrinsic mode functions (IMFs), which are then distinguished by the Hurst exponent to reconstruct the filtered signal. Subsequently, the scale signals are obtained by using gradient calculation and discrete wavelet transform and are then fused by using WEP. Finally, TEO is implemented to enhance defect signal amplitude, completing geomagnetic detection of pipeline defects. The simulation results created by magnetic dipole in a noisy environment, indoor experiment results and field testing results certify that the proposed method outperforms ensemble empirical mode decomposition (EEMD)-gradient, EEMD-WEP-TEO, CEEMDAN-gradient in terms of detection deviation, peak side-lobe ratio (PSLR) and integrated side-lobe ratio (ISLR).
EN
In this study, the optimum parameters of membrane desalinization of model solutions were determined and the required efficiency was achieved. Methods for stabilizing treatment of water before barometric desalination were developed to improve the efficiency of membranes. Methods of reagent processing of concentrates after barometric water were proposed to create a low-waste technologies for demineralization of water. It was shown that the precipitate can be used as an additive for cements and a sulfate activator for slag-portland cement.
EN
Strong motion recordings are the key in many earthquake engineering applications and are also fundamental for seismic design. The present study focuses on the automated correction of accelerograms, analog and digital. The main feature of the proposed algorithm is the automatic selection for the cut-off frequencies based on a minimum spectral value in a predefined frequency bandwidth, instead of the typical signal-to-noise approach. The algorithm follows the basic steps of the correction procedure (instrument correction, baseline correction and appropriate filtering). Besides the corrected time histories, Peak Ground Acceleration, Peak Ground Velocity, Peak Ground Displacement values and the corrected Fourier Spectra are also calculated as well as the response spectra. The algorithm is written in Matlab environment, is fast enough and can be used for batch processing or in real-time applications. In addition, the possibility to also perform a signal-tonoise ratio is added as well as to perform causal or acausal filtering. The algorithm has been tested in six significant earthquakes (Kozani-Grevena 1995, Aigio 1995, Athens 1999, Lefkada 2003 and Kefalonia 2014) of the Greek territory with analog and digital accelerograms.
PL
Przedmiotem badań, których wyniki przedstawiono w pracy, jest proces rozdzielania zdyspergowanych układów dwufazowych typu olej w wodzie (0/W) i woda w oleju (W/0) realizowany z wykorzystaniem wysokosprawnych struktur koalescencyjnych. Szczególny nacisk położono na usuwanie zemulgowanej wody z oleju napędowego, co stanowiło główny nurt badawczy i doprowadziło do opracowania nowatorskiego rozwiązania dwustopniowego kompaktowego filtra do montażu w pojazdach wyposażonych w silniki wysokoprężne. W pierwszym rozdziale pracy dokonano przeglądu metod separacji układów ciecz-ciecz, z naciskiem na urządzenia wyposażone w elementy koalescencyjne do rozdzielania stabilnych emulsji. Wskazano powszechnie obserwowane trudności oraz przedyskutowano znaczenie najistotniejszych parametrów, mających bezpośredni wpływ na ograniczenie skuteczności pracy struktur koalescencyjnych. Wykonano studium literaturowe dotyczące mechanizmu koalescencji rozproszonych kropel unoszonych w przepływie i związanych z nim modeli efektywności ich łączenia się. Następnie zestawiono i przedyskutowano różnorodne zależności opisujące skuteczność wychwytywania i koalescencji kropel dyspersji przepływającej przez złoże porowate. Sformułowano nowy model pozwalający na opis zjawisk depozycji i ociekania dużych kropel po koalescencji dla pojedynczej komórki obliczeniowej, który uwzględnia zarówno wpływ zwilżalności włókien i związanego z tym nasycenia struktury na skuteczność separacji, jak i umożliwia oszacowanie rozmiarów kropel i mechanizmów prowadzących do ich odłączania na wylocie. W części eksperymentalnej przeprowadzono w szerokim zakresie prace doświadczalne separacji dyspersji ciecz-ciecz z wykorzystaniem struktur polimerowych, celulozowych i włókien szklanych, w ramach których zweryfikowano tendencje podawane w literaturze przedmiotu oraz sformułowano wnioski, których część okazała się przeciwstawna doniesieniom literaturowym. Dla wyników odbiegających od ustalonych opinii nt. koalescencji kropel w strukturach włókninowych przedstawiono interpretację domniemanych mechanizmów mających wpływ na przebieg procesu. W ramach prac laboratoryjnych wykonano szereg modyfikacji badanych struktur koalescencyjnych w celu poprawy ich skuteczności. Badania separacji emulsji przeprowadzono w samodzielnie zaprojektowanej instalacji testowej, której uniwersalny charakter umożliwia badania separacji dyspersji wody w oleju i odwrotnej, a także prowadzenie eksperymentów w szerokim zakresie parametrów operacyjnych i dla różnej geometrii warstw włókninowych. Zwieńczeniem realizowanych badań doświadczalnych, wspartych teoretyczną analizą zjawisk i ich numerycznym opisem, jest zgłoszenie patentowe oraz praktyczne zastosowania opracowanych rozwiązań, których szczegóły przedstawiono w ostatnim rozdziale pracy.
EN
The aim of the monograph is the separation of liquid-liquid emulsions performed using fibrous coalescence media. The emphasis was put on removal of dispersed water from diesel fuel, which was the main course of the research work. The problems of diesel fuel filtration are commonly observed issue due to change of fuel properties in recent years. Hence, devising of a high-efficiency water separation system arises from a real demand from filter manufacturers. The research described in the monograph led to designing of a new two-stage filter for mounting directly in vehicles, but it can be easily scaled-up for higher throughputs. In first part of this work a review of coalescence separators for highly emulsified and stable dispersions was carried out. The parameters which negatively affect the separation performance were pointed out. A literature study on mechanism of binary coalescence between two free-flowing droplets was done, including review of the coalescence efficiency models. Then relations and models, which describe the operation of the coalescence porous media, were presented and discussed. The new modelling approach for deposition of emulsion droplets and drainage of large ones after the coalescence, i.e. detaching from the fibrous structures, was formulated. The model includes the effect of fiber wettability and saturation on the efficiency of separation as well as it allows to estimate the size of detached droplets, and determine a dominant mechanism leading to droplet disengagement. Its assumptions and simplifications were discussed in details. In experimental part of the work a wide range of experiments were carried out using the coalescence structures made of polymers, fiberglass and cellulose. The tendencies described in literature were verified. For results which do not comply with trends reported in literature, own interpretation of mechanisms which affect the process was proposed. Some modifications of coalescence structures were carried out, the properties of applied functionalization was verified in laboratory, and in final stage the effect of modification was established in emulsion separation test. The in-house designed test rig enabled examination of various elements, i.e. in form of flat sandwiched multilayer media or in form of cylindrical cartridges of various sizes. The universal design of the experimental system allowed testing of both O/W or W/O emulsions at a wide range of operating parameters. The experimental research programme supported with theoretical analysis of mechanisms and its numerical description enabled to design a new type of diesel filter, which was patented. The prototype system was built and the high-efficiency was confirmed in testing, as described in last chapter of the monograph. Other practical applications of coalescence media designed for a specific process were described.
PL
Poniższy artykuł ma na celu określenie wpływu na jakość pszenicy zastosowania w uprawie preparatów zawierających pożyteczne mikroorganizmy. Podczas przeprowadzonych badań określono wpływ tych preparatów na zawartości makroskładników w glebie oraz na zawartość składników będących podstawowymi parametrami ziarna pszenicy konsumpcyjnej.
EN
The following article is intended to determine the effect of wheat on the use of preparations containing useful microorganisms. The results of the investigations determine the influence of these formulations on the content of macronutrients in soil and on the content of components which are the basic parameters of wheat grain consumption.
18
Content available Filtracja a czystość cieczy hydraulicznych
PL
W artykule przedstawiono rozważania dotyczące filtracji cieczy roboczej w układach hydraulicznych oparte na przyjętym modelu matematycznym zjawiska. Rozważano zależność liczby zanieczyszczeń w cieczy hydraulicznej (popularnie „klasy czystości medium”) od wybranych czynników. W szczególności wzięto pod uwagę: współczynnik filtracji βx, natężenie przepływu przez filtr Q, objętość cieczy roboczej V zawartej w układzie hydraulicznym oraz strumień zanieczyszczeń Θ. Wyniki analizy wskazują, że bardzo ważnym czynnikiem wpływającym na czystość cieczy roboczej jest natężenie przepływu przez filtr.
EN
In paper is presented a model of the filtering phenomena in the hydraulic system. Was analyzed relationship between the cleanliness of hydraulic liquid and different variables. Into consideration were taken: the filter efficiency βx, flowrate Q through the filter, the volume of hydraulic liquid V contained into system, stream of pollution solid particles Θ. The results showed that the most effective way to improve the cleanliness of the hydraulic fluid is the increasing of the volume flow rate through the filter.
EN
Recognition of objects in pictures and movies requires the use of techniques, such as filtering, segmentation and classification. Image filtering is required to remove all artifacts that hinder the unequivocal identification and sharpen interesting objects. Segmentation refers to finding areas of images respected to individual objects. For the selected areas corresponding to objects in the selected picture, the classification of objects finally gives information about the type of object which orientation is made. This paper presents a method for the classification of objects from drawings as a bitmap using the method of fundamental solutions (MFS). The MFS was tested on the selected bitmap depicting simple geometric shapes. The correlations between errors occurring on the boundary for particular shapes are used for the selection of geometric shape figures. Due to this correlation, it is possible to recognize the shape of the image appearing on the drawing by an analysis consisting of the comparison of recognized points describing the shape of contour to a database containing solutions of boundary value problems for the selected shape. In one way, the comparison of the pattern can determine which shape from database it is most similar to in terms of contour. This article appear that this approach is very simple and clearly. In result, this method can be used to recognition of the objects in the systems of real-time processing.
EN
Detection of an object motion is the growing research field of image processing which revealed the several applications. Several techniques (including the proposed one) are discussed so far in literatures. In this paper the edge detection and frame differencing also known as background subtraction technique with block matching algorithm has been implemented to detect the object motion. The object taken for experimentation is arbitrary having no fixed shape and size. The MATLAB output result showing the practicability of the both algorithms.
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