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EN
In this study, the Artificial Neural Network (ANN) models and multiple linear regression techniques were used to estimate the relation between the concentration of total coliform, E. coli and Pseudomonas in the wastewater and the input variables. Two techniques were used to achieve this objective. The first is a classical technique with multiple linear regression models, while the second one is data mining with two types of ANN (Multilayer Perceptron (MLP) and Radial Basis Function (RBF). The work was conducted using (SPSS) software. The obtained estimated results were verified against the measured data and it was found that data mining by using the RBF model has good ability to recognize the relation between the input and output variables, while the statistical error analysis showed the accuracy of data mining by using the RBF model is acceptable. On the other hand, the obtained results indicate that MLP and multiple linear regression have the least ability for estimating the concentration of total coliform, E. coli and pseudomonas in wastewater.
PL
Rozlewanie się miast powoduje pogorszenie jakości zamieszkania, utrudnia dostęp służb ratowniczych, a także wpływa na zanieczyszczenie środowiska. Osiedla podmiejskie rozwijają się chaotycznie i pochłaniają ogromne obszary, co przekłada się na jakość infrastruktury. Brak sieci wodociągowej i kanalizacyjnej oznacza indywidualne ujęcia wody i zbiorniki szczelne, często nielegalnie zamieniane na przydomowe oczyszczalnie ścieków. Brak sieci gazowej i ciepłowniczej oznacza korzystanie z paliw stałych i ciekłych, a w praktyce smog. Obraz dopełnia długotrwałe czekanie w korku. Rozlewanie się miast ma zatem bezpośredni wpływ na aspekty zdrowotne. W tym kontekście badanie skoncentrowane jest na stworzeniu modelu analitycznego, którego zastosowanie pozwala określać parametry warunkujące tempo rozwoju, a przez to wspomagać proces planowania przestrzennego. Badania przeprowadzono na wybranych terenach mieszkaniowych objętych planami miejscowymi w granicach aglomeracji poznańskiej.
EN
Urban sprawl causes a deterioration in the quality of housing, hinders access to emergency services, and also influences the environmental pollution. Suburban development is chaotic and absorbs huge areas. In turn, it leads to the low quality of infrastructure. Lack of water supply and sewage treatment results in individual water intakes and septic tanks, often illegally turned into individual sewage treatment plants. Lack of gas and heating network causes the usage of solid and liquid fuels, and in practice smog emission. The picture is completed with traffic jams. Therefore, urban sprawl has also a direct impact on the public health issues. In this context, the research is focused on establishing a regression model. Its application will allow to determine the parameters indicating the future development. This model can be used as the spatial planning supporting. The study was conducted in selected residential areas covered by local spatial development plans according to within the Poznan urban agglomeration out of city area.
EN
Nowadays, unprecedented amounts of heterogeneous data collections are stored, processed and transmitted via the Internet. In data analysis one of the most important problems is to verify whether data observed or/and collected in time are genuine and stationary, i.e. the information sources did not change their characteristics. There is a variety of data types: texts, images, audio or video files or streams, metadata descriptions, thereby ordinary numbers. All of them changes in many ways. If the change happens the next question is what is the essence of this change and when and where the change has occurred. The main focus of this paper is detection of change and classification of its type. Many algorithms have been proposed to detect abnormalities and deviations in the data. In this paper we propose a new approach for abrupt changes detection based on the Parzen kernel estimation of the partial derivatives of the multivariate regression functions in presence of probabilistic noise. The proposed change detection algorithm is applied to oneand two-dimensional patterns to detect the abrupt changes.
EN
The Electroencephalogram (EEG) recordings from the frontal lobe of the human brain help in analyzing several important brain functions like motor functions, problem-solving skills, etc. or brain disorders. These recordings are often contaminated by high amplitude and long duration ocular artifacts (OAs) like eye blinks, flutters and lateral eye movements (LEMs), hence corrupting a considerable segment of EEG. In this study, an enhanced version of signal decomposition scheme i.e. Variational Mode Decomposition (VMD) based algorithm is used for suppression of OAs. The signal decomposition is preceded by identification of ocular artifact corrupted segment using Multiscale modified sample entropy (mMSE). The band limited intrinsic mode functions (BLIMFs) are obtained using predefined K (number of required BLIMFs) and α (balancing parameter). These parameters help to detrend the EEG segment in yielding the low frequency and high amplitude BLIMFs related to OA efficiently. Upon identifying OA components from the BLIMFs and estimating OA, it is regressed with the contaminated EEG to obtain the clean EEG. The proposed VMD based algorithm provides an improved performance in comparison with the existing single channel algorithms based on Empirical mode decomposition (EMD) and Ensembled EMD (EEMD) and multi-channel algorithms like Independent component analysis (ICA) and wavelet enhanced ICA for artifact suppression and is also able to overcome their limitations. The significance of the algorithm are: (1) no additional reference EOG channel requirement, (2) OA artifact based thresholds for identification and estimation from the mode functions obtained using VMD, and (3) also address the flutter artifacts.
EN
This study presents an assessment of the equivalence of measurements of particulate matter PM10 concentrations using a low-cost electronic device as compared to the reference method. Data for the study were collected in accordance with the guidelines for research equivalence of the two devices operating in parallel. On this basis, a model correcting raw measurement results was developed. The best results were obtained for the model having the form of a second degree polynomial and taking into account air temperature. Corrected measurement results were used in the equivalence testing procedure. As a result, confirmation of equivalence was obtained for the vast majority of data sets generated from original measurements. This confirms the usefulness of the device as a tool for monitoring air quality.
PL
W pracy przedstawiono identyfikację charakterystyk energetycznych kotłów dla potrzeb diagnostyki i optymalizacji eksploatacji. Dla skorygowania nieuniknionych błędów pomiaru i uzyskania wymaganej dokładności predykcji zastosowano rachunek wyrównawczy. Estymację parametrów i dobór optymalnej struktury dokonano metodą regresji krokowej. W procedurze estymacyjnej wykorzystano pomiary eksploatacyjne i specjalne oraz wyniki obliczeń symulacyjnych z wykorzystaniem modeli matematycznych. Przedstawiono wyniki identyfikacji charakterystyk energetycznych kotła pyłowego elektrowni kondensacyjnej, kotła rusztowego ciepłowni i kotła wielopaliwowego w hutnictwie miedzi. Omówiono przydatność opracowanych modeli w systemach diagnostyki eksploatacji i w optymalizacji bieżącej w systemach sterowania.
EN
The paper presents mathematical modelling of steam boilers by the usage of regression modelling techniques for the purpose of thermal diagnostic systems and exploitation optimization. In order to correct unavoidable measurement errors and to achieve the satisfying prediction quality of developed models Advanced Data Validation and Reconciliation method has been used. The estimation procedure of model parameters and determination of optimal structure of developed model have been carried out with stepwise regression technique. Within estimation procedure, operational measurements as well as simulation calculation results (with usage of mathematical models) have been used. The results related to identification of coal dust fired boiler, stoker-fired boiler as well as multi fuel industrial boiler energy characteristics have been presented. The usage of developed models have been described from the thermal diagnostic systems as well as exploitation optimization point of view.
EN
This article presents regression formulas for the preliminary design of tankers, bulk carriers and container vessels, based on the data of ships built from 2000 to 2018. The formulas could have practical application for the estimation of total engine power by using ship’s deadweight or TEU capacity and speed. The regressions presented in this article are based on the most recent data and were developed for individual sub-types of tankers, bulk carriers and container ships. The presented regressions comply with trends found in the literature and offer greater accuracy for characteristics of new-built ships.
EN
The relationships between atmospheric circulation patterns and water surface temperature along the coast of the southern Baltic Sea were studied. Seasonal water temperature values for Świnoujście, Międzyzdroje, Kołobrzeg, Władysławowo, Hel and Gdynia stations measured during the period of 1951-2010 were used. The methods of correlation and regression were applied to determine the relationships between water temperature and the number of days of atmospheric circulation patterns. It was demonstrated that the strongest relationships occur in winter, chiefly on account of intense atmospheric circulation activity and weaker effects of solar radiation. The relationships with western circulation are slightly stronger than that associated with the eastern circulation. During the remaining seasons, those dependencies are clearly weaker. Asynchronous relationships between water temperature and atmospheric circulation are less pronounced than the synchronous ones. Despite being weaker, the asynchronous relations are still statistically significant, mainly in the spring season and as such, they may have a prognostic significance.
PL
Na tle innych obiektów pływających jacht żaglowy wyróżnia się m.in. tym, że choć jest zaprojektowany jako pojazd poruszający się w pozycji wyprostowanej, to jednak znaczną część czasu żegluje w przechyle. Dlatego tak ważne jest poznanie zachodzących wtedy zjawisk, zwłaszcza związanych z oporem hydrodynamicznym. W artykule zaprezentowano porównanie oparte na weryfikacji wybranej, przybliżonej metody oszacowania zmian oporu całkowitego gołego kadłuba w wyniku jego przechylania się, polegającej na sprawdzeniu wykonanym metodą numeryczną (CFD) i eksperymentalną (przez badania modelowe). Obliczenia uproszczone oparto na metodach opracowanych w ramach serii Delft (The Delft Systematic Yacht Hull Series, DSYHS). W artykule przedstawiono wyniki oszacowań dla wybranego jachtu żaglowego.
EN
Unlike other floating structures yachts sail in heel most of their life, however, resistance in design process is estimated in upright condition. Thus, it is crucial to investigate into phenomena related to change of hull resistance due to heel. This article presents assessment of influence of yacht’s heel on bare hull resistance using approximate method. Results were compared to towing tank experiments and numerical computation (CFD). Calculations were performed using formulae developed based on The Delft Systematic Yacht Hull Series. Article presents results of analysis for specific sailing yacht.
EN
In this article, we present a comprehensive measurement system to determine the level of user emotional arousal by the analysis of electrodermal activity (EDA). A number of EDA measurements were collected, while emotions were elicited using specially selected movie sequences. Data collected from 16 participants of the experiment, in conjunction with those from personal questionnaires, were used to determine a large number of 20 features of the EDA, to assess the emotional state of a user. Feature selection was performed using signal processing and analysis methods, while considering user declarations. The suitability of the designed system for detecting the level of emotional arousal was fully confirmed, throughout the number of experiments. The average classification accuracy for two classes of the least and the most stimulating movies varies within the range of 61‒72%.
EN
Roundabout entry capacity is influenced by geometric features of the roundabout, traffic flow characteristics, vehicle are checked. In comparison with the existing empirical models such as the LR942 regression model and German empirical model, the proposed regression model produced better estimates and much lower RMSE values. Approach width is found to have the highest impact on entry capacity. The entry capacity is found to be negatively influenced by entry angle. Circulating flow is considered in terms of per metre width against the usual convention. This modification incorporates the effect of circulatory roadway width also into consideration. The circulatory roadway width has a diverse effect on entry capacity at different levels of circulating flow. Modification of inscribed circle diameter and circulatory roadway width is suggested as a potential solution for improving entry capacity. Sensitivity analysis is carried out to quantify the effect of variation of entry angle, circulatory roadway width, inscribed circle diameter and approach width on entry capacity based on the non-linear model. The sensitivity plots can be used to make subtle geometric modifications to improve capacity at congested roundabouts.
EN
This review paper presents a shortcoming associated to data mining algorithm(s) classification, clustering, association and regression which are highly used as a tool in different research communities. Data mining researches has successfully handling large amounts of dataset to solve the problems. An increase in data sizes was brought a bottleneck on algorithms to retrieve hidden knowledge from a large volume of datasets. On the other hand, data mining algorithm(s) has been unable to analysis the same rate of growth. Data mining algorithm(s) must be efficient and visual architecture in order to effectively extract information from huge amounts of data in many data repositories or in dynamic data streams. Data visualization researchers believe in the importance of giving users an overview and insight into the data distributions. The combination of the graphical interface is permit to navigate through the complexity of statistical and data mining techniques to create powerful models. Therefore, there is an increasing need to understand the bottlenecks associated with the data mining algorithms in modern architectures and research community. This review paper basically to guide and help the researchers specifically to identify the shortcoming of data mining techniques with domain area in solving a certain problems they will explore. It also shows the research areas particularly a multimedia (where data can be sequential, audio signal, video signal, spatio-temporal, temporal, time series etc) in which data mining algorithms not yet used.
EN
Sedimentary features of the Cambrian-age succession transected in seven borehole cores sited in the Podlasie region document vertical and lateral variations of shallow-marine sedimentary facies, deposited at the rifted western margin of the Baltica Palaeocontinent. The boreholes are distributed along two lines of cross-section (E–W and NE–SW) running roughly perpendicular to the margin of the palaeocontinent. The easternmost borehole represents a proximal setting located on a relatively stable, shallow basement in the east; the remaining boreholes document conditions of deposition in the subsiding shallow-marine basin, extending towards the SW. Fourteen sedimentary facies defined on the basis of their lithological and sedimentary features are interpreted in terms of the sedimentary environments they represent. Strata deposited upon the stable craton in the east document a stratigraphically condensed succession of proximal facies, 240 m thick, whereas a sequence three times thicker is positioned distally, 170 km to the west. Facies associations in the proximal section represent the lower to upper shoreface in the lower part of the section and evolve upwards to the intermediate shoreface. Facies complexes in the remaining, intermediate and distal areas form a symmetrical megasequence, composed of a positive (i.e., fining-upwards – FU) transgressive sequence, overlain by a negative (coarsening-upwards – CU) regressive sequence. The vertical arrangement of the sedimentary subenvironments during the transgression indicates a tidally influenced shoreline followed by oscillations between the swash zone, the upper, intermediate and lower shoreface, and the offshore. The symmetry of the megasequences and the rhythmic pattern of the component facies complexes indicate that the intensity of supply in the terrigenous material and the efficiency of its reworking and redistribution within the basin were similar during the transgression and the regression. The facies types and variations within the basal part of the succession reflect syndepositional movements of tectonic blocks parallel to the rifted basin margin. Differences in total thickness and facies associations between the two lines of cross-section approximately perpendicular to the basin margin indicate that sedimentation was also influenced by a synsedimentary hinge fault, extending in a WSW–ENE direction.
PL
Celem artykułu jest przedstawienie możliwości wykorzystania testu zgodności chi-kwadrat, analizy korelacji i modelu regresji liniowej w modelowaniu zagrożeń. Są to metody zarówno proste na etapie tworzenia, jak i łatwe w interpretacji. Na potrzeby artykułu przyjmuje się, że modelowanie zagrożeń, to użycie sformalizowanego języka do analizy i opisania, za pomocą zmiennych, wybranego zagrożenia. Zastosowane metody umożliwiają wykorzystanie dostępnych informacji, takich jak: dane przetwarzane przez Główny Urząd Statystyczny, dane statystyczne Komendy Głównej Państwowej Straży Pożarnej czy wyniki Diagnozy Społecznej lub nowych, zbieranych w toku prac badawczych danych w obszarze bezpieczeństwa do budowania wielowymiarowych modeli. Modele te umożliwiają ilościową analizę zagrożeń, której wyniki pozwalają wykonać obiektywne testy i ocenę wybranych zagadnień.
EN
The aim of the paper is to introduce the possibility of use of the square-chi consistency test, the correlation analysis as well as the linear regression model in the threats simulation. The methods are both simple on the creation level and easy to interpret. The accepted threats simulation definition is the use of formal language for analysis and description, using variables of the selected threat. The applied methods use available information such as: data used by the Central Bureau for Statistics (GUS), statistic data of National Headquarters of State Fire Service, the results of Social Diagnosis or new, collected data obtained during all kinds of the research activities dealing with the safety. All of them make the construction of multidimensional models possible. The models enable to carry the quantitative threat analysis, the results of which can make objective tests and evaluation of the selected threats.
PL
Rewizja opiera się na weryfikacji wybranych przybliżonych metod prognozowania oporu całkowitego gołego kadłuba, opracowanych w wyniku badań systematycznej serii kadłubów jachtów żaglowych w latach 1973–2010, znanych jako The Delft Systematic Yacht Hull Series (DSYHS). Zademonstrowano wyniki otrzymane z wykorzystaniem wzorów przybliżonych (Metoda Delft), obliczeń numerycznych (CFD) i badań modelowych dla wybranego jachtu żaglowego o nowoczesnym kształcie kadłuba wraz z ich dyskusją.
EN
The revision is based on the verification of approximate methods of the prediction of the total resistance of the bare hull developed in the results of a systematic study of a series sailboat hulls from 1973 to 2010 known as The Delft Systematic Yacht Hull Series (DSYHS). Demonstrations were obtained based on approximate formulas (Delft method), numerical calculations (CFD) and the towing tank test for a selected sailing yacht with a modern hull shape along with a discussion of results.
EN
The mi is an important parameter in the use of the Hoek–Brown failure criterion. It can be estimated using a triaxial compressive strength test but in many projects there is no actual test result for the parameter. An estimation of mi comes from a reference table giving a constant value. Elsewhere some empirical equations for the value were suggested in the 1990s. Applying these equations is limited use since they are available for a few rock types and the equations are based on just uniaxial compressive strength tests of rock. In this research rocks were divided into three categories (Igneous, Sedimentary and Metamorphic) and three empirical formulas are suggested for the categories based on uniaxial compressive strength (σci) and tensile strength (σt) of rocks by nonlinear regression. The equations have been obtained by a combination of the two independent parameters and the trial and error method was used to find the equations with the highest correlation coefficient. The data base uses data from many original international research projects and much data from Iranian tunnelling projects. The models have a high level of accuracy and have been used to describe most rock types although the authors know that the technique can be improved using a new and larger collection of data in the future.
EN
The purpose of the following work is to review the methods used in predicting plant yields, with particular emphasis on potato production. The article refers to the histological methods of estimating plant yields and prevailing trends: groundbased remote sensing, which is often associated with regression calculus, multiple regression, artificial intelligence and image analysis. There are also two popular models SUBSTOR and LINTUL-POTATO, which are the foundation for developing more and more accurate tools of potato yield estimation. There are many methods that allow to predict yields before the end of the growing season. The most important element in creating prediction models is choosing the appropriate number of independent variables that actually shape the yielding of potatoes. Timely and accurate prediction of crop yields improve the management of agricultural production as well as limit financial, quantitative and qualitative losses of crops.
PL
Celem niniejszej pracy był przegląd metod wykorzystywanych w prognozowaniu plonów roślin ze szczególnym uwzględnieniem produkcji ziemniaka. W artykule nawiązano do historycznych sposobów szacowania plonów roślin oraz obecnie panujących trendów w predykcji: teledetekcji naziemnej, która często powiązana jest z rachunkiem regresyjnym, regresji wielorakiej, sztucznej inteligencji, analizie obrazów. Wspomniano także o dwóch popularnych modelach SUBSTOR i LINTULPOTATO, które stworzyły podwaliny do opracowywania coraz dokładniejszych narzędzi prognozujących plony ziemniaków. Wiele metod pozwala na predykcję plonów przed zakończeniem sezonu wegetacyjnego. Najistotniejszym elementem tworzenia modeli predykcyjnych jest dobór odpowiedniej liczby zmiennych niezależnych, które rzeczywiście kształtują plonowanie ziemniaków. Terminowe i dokładne prognozy plonów roślin uprawnych usprawniają zarządzanie produkcją rolniczą, pozwalają na ograniczanie strat finansowych, ilościowych i jakościowych plonów.
EN
This study focuses on modelling general and individual language change over several decades. A timeline prediction task was used to identify interesting temporal features. Our previous work achieved high accuracy in predicting publication year, using lexical features marked for syntactic context. In this study, we use four feature types (character, word stem, part-of-speech, and word n-grams) to predict publication year, and then use associated models to determine constant and changing features in individual and general language use. We do this for two corpora, one containing texts by two different authors, published over a fifty-year period, and a reference Corpus containing a variety of text types, representing general language style over time, for the same temporal span as the two authors. Our linear regression models achieve good accuracy with the two-author data set, and very good results with the reference corpus, bringing to light interesting features of language change.
PL
Biorąc pod uwagę poziom gazyfikacji Polski, szacowanie zadań inwestycyjnych i ich wybór do realizacji jest zagadnieniem istotnym dla przedsiębiorstwa energetycznego. Wiele z nowych inwestycji przeznaczonych do realizacji, planowane jest z wykorzystaniem technologii LNG oraz wyspowych sieci dystrybucyjnych. Z uwagi na wiele ryzyk związanych z szacowaniem zadań inwestycyjnych, kluczowe dla przedsiębiorstwa energetycznego jest wybieranie takich inwestycji, które gwarantują oczekiwane wskaźniki efektywności ekonomicznej. Dodatkowo szacowanie inwestycji, poprzez wywiady i bezpośrednia analizę danej lokalizacji, jest procesem czasochłonnym i kosztownym. Niniejszy artykuł jest próbą znalezienia odpowiedzi na pytanie, czy można, przynajmniej wstępnie, przy pomocy relatywnie prostych metod, np. przy wykorzystaniu analizy statystycznej dotychczasowych zadań inwestycyjnych, wskazać metodę na wstępną selekcję zadań inwestycyjnych, które będą opłacalne z punktu widzenia przedsiębiorstwa energetycznego. Korzyścią z takiego podejścia będzie to, iż szczegółowe analizy techniczno-ekonomiczne przedsięwzięć zostałoby ograniczone do wstępnie zweryfikowanych zadań inwestycyjnych.
EN
Taking into account the level of gasification in Poland, the estimation of investment tasks and their selection for implementation is an important issue for an energy company. Many of the new investments planned for implementation are planned using LNG technology and separated distribution networks. Due to many risks associated with the estimation of investment tasks, it is crucial for an energy company to choose investments that guarantee the expected economic efficiency indicators. In addition, estimating investments through interviews and direct analysis for a particular location is a time-consuming and costly process. This article is an attempt to find the answer to the question whether it is possible, at least initially, using relatively simple methods, eg. using statistical analysis of current investment tasks, to indicate a method for initial selection of investment tasks which will be profitable from the energy company's point of view. The benefit of this approach will be that the detailed technical and economic analysis of the investment projects would be limited to pre-verified investment tasks.
EN
The aim of this study was to identify the determinants of peak power achieved during vertical jumps in order to clarify relationship between the height of jump and the ability to exert maximum power. Methods: One hundred young (16.8±1.8 years) sportsmen participated in the study (body height 1.861 ± 0.109 m, body weight 80.3 ± 9.2 kg). Each participant performed three jump tests: countermovement jump (CMJ), akimbo countermovement jump (ACMJ), and spike jump (SPJ). A force plate was used to measure ground reaction force and to determine peak power output. The following explanatory variables were included in the model: jump height, body mass, and the lowering of the centre of mass before launch (countermovement depth). A model was created using multiple regression analysis and allometric scaling. Results: The model was used to calculate the expected power value for each participant, which correlated strongly with real values. The value of the coefficient of determination R2 equalled 0.89, 0.90 and 0.98, respectively, for the CMJ, ACMJ, and SPJ jumps. The countermovement depth proved to be a variable strongly affecting the maximum power of jump. If the countermovement depth remains constant, the relative peak power is a simple function of jump height. Conclusions: The results suggest that the jump height of an individual is an exact indicator of their ability to produce maximum power. The presented model has a potential to be utilized under field condition for estimating the maximum power output of vertical jumps.
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