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EN
Purpose: The aim of the article was to prepare a simulation analysis of artificial neural network and XGBoost algorithm with determining which of the method was characterized by a lower level of forecast errors for time series predictions. Design/methodology/approach: The objective of the article was reached by applying, a simulation study on a sample of 1000 artificially generated time series. The analyzed XGBoost algorithm and the artificial neural network ANN model were intended to prepare forecasts for five periods ahead. These forecasts were compared with the actual implementations of the time series and proposed forecast error measures. Findings: It is possible to use simulated time series to check which of the presented algorithms were characterized by a lower forecast error. The study showed that applying of the artificial neural networks ANN to forecast future observations generated a lower level of MAPE, MAE and RMSE errors than in the case of the XGBoost algorithm. It was found that both methods generate a lower level of forecast error for time series characterized by a high level of mean value, standard deviation and variance, and levels of kurtosis and skewness close to 0. Practical implications: The research results can be used by both investors and enterprises to better adjust their business decisions to changing market prices by using a model with a lower forecast bias. Originality/value: The original contribution of this article is a comprehensive comparison of forecasts generated by the XGBoost and ANN algorithm, along with determining for which types of time series of the algorithms forecast future values with less error. Moreover, due to the use of simulated artificial time series, it was possible to test each algorithm for various market conditions.
EN
This review article explores the historical background and recent advances in the application of artificial intelligence (AI) in the development of radiofrequency pulses and pulse sequences in nuclear magnetic resonance spectroscopy (NMR) and imaging (MRI). The introduction of AI into this field, which traces back to the late 1970s, has recently witnessed remarkable progress, leading to the design of specialized frameworks and software solutions such as DeepRF, MRzero, and GENETICS-AI. Through an analysis of literature and case studies, this review tracks the transformation of AI-driven pulse design from initial proof-of-concept studies to comprehensive scientific programs, shedding light on the potential implications for the broader NMR and MRI communities. The fusion of artificial intelligence and magnetic resonance pulse design stands as a promising frontier in spectroscopy and imaging, offering innovative enhancements in data acquisition, analysis, and interpretation across diverse scientific domains.
EN
In mining, where production is affected by several factors, including equipment availability, it is necessary to develop reliable models to accurately predict mine production to improve operational efficiency. Hence, in this study, four (4) machine learning algorithms - namely: artificial neural network (ANN), random forest (RF), gradient boosting regression (GBR) and decision tree (DT)) - were implemented to predict mine production. Multiple Linear Regression (MLR) analysis was used as a baseline study for comparison purposes. In that regard, one hundred and twenty-six (126) datasets from an open-pit gold mine were used. The developed models were evaluated and compared using the correlation coefficient (R2), mean absolute percentage error (MAPE) and variance accounted for (VAF). It has been shown in this study that the ANN model can best estimate open-pit mine production by comparing its performance to that of the other machine learning models. The R2, MAPE, RMSE and VAF of the models were 0.8003, 0.7486, 0.7519, 0.6538, 0.6044, 4.23%, 5.07%, 5.44%, 6.31%, 6.15% and 79.66%, 74.69%, 74.10%, 65.16% and 60.11% for ANN, RF, GBR, DT and MLR, respectively. Overall, this study has shown that machine learning algorithms predict mine production with higher accuracy.
EN
The interpretation of breast magnetic resonance imaging (MRI) in the healthcare field depends on the good knowledge and experience of radiologists. Recent developments in artificial intelligence (AI) have shown advances in the field of radiology. However, the desired levels have not been reached in the field of radiology yet. In this study, a novel model structure is proposed to characterize the diagnostic performance of AI technology for individual breast dynamic contrast material–enhanced (DCE) MRI sequences. In the proposed model structure, Inception-v3, EfficientNet-B3, and DenseNet-201 models were used as hybrids together with the Yolo-v3 algorithm to detect breast and cancer regions. In the proposed model, DCE-MRI sequences (T2, ADC, Diffusion, Non-Contrast Fat Non-Suppressed T1, Non-Contrast Fat Suppressed T1, Contrast Fat Suppressed T1, and Subtraction T1) were evaluated separately and validation was made, thus providing a unique perspective. According to the validation results, the model structure with the best performance was determined as Yolo-v3 + DenseNet-201. With this model structure, 92.41% accuracy, 0.5936 loss, 92.44% sensitivity, and 92.44% specificity rates were obtained. In addition, it was determined that the results obtained without using contrast material in the best model were 91.53% accuracy, 0.9646 loss, 92.19% sensitivity, and 92.19% specificity. Therefore, it is predicted that the need for contrast material use can be reduced with the help of this model structure.
EN
Plantar pressure distribution offers insights into foot function, gait mechanics, and foot-related issues. This systematic review presents an analysis of the use of artificial neural network techniques in the context of plantar pressure analysis. 60 studies were included in the review. Sample size, pathology, pressure sensor number, data collection device, utilization of other sensor devices, ground-truth methods, pre-processing dataset, neural network type, and evaluation metrics were evaluated. Utilization of customized wearable footwear devices for the acquisition of data was common amongst both healthy participants and patients. Inertial measurement units emerged as an effective compensatory measure to address the limitations associated with the distribution of plantar pressure. Ground truth methods predominantly relied on the usage of both annotations and reference devices. Multilayer perceptron, convolutional neural networks, and recurrent neural networks were identified as the most frequently employed artificial neural network algorithms across the reviewed studies. Finally, the evaluation of performance largely drew upon statistical descriptions and other machine learning methods. This review provides a comprehensive understanding of the use of artificial neural network techniques in plantar pressure analysis, highlighting opportunities for future research.
EN
In recent years, the groundwater resources of Arak plain have been under severe stress, so in some areas, due to the drying up of wells, the depth of wells has increased to access water. In some areas, the groundwater depth is high, which will lead to the salinization of those lands in the future. Regional modeling was used to organize and measure the response of the groundwater resources of Arak plain against the implementation of different management and implementation scenarios. This study aims to investigate the effective factors in the groundwater depth to provide a regional model with multiple linear regression (MLR) methods for Arak plain aquifer. For this purpose, the average groundwater potential maps (GPMs) in the Arak plain, as a dependent variable, and the transmissivity of the aquifer formations, groundwater exploitation values, altitude, average precipitation of the region, the amount of evaporation, and the distance from water resources are considered independent variables and regression analysis is done in SPSS software media. It was done to present a linear model. In the next stage, the presented model was evaluated by applying it to places where its statistics and information were not used to present the model, and finally, by applying this model in the GIS environment, the GPMs for the region were created. The study was prepared. Also, an artificial neural network (ANN) was used to simulate the depth of underground water. The performance of the ANN was measured through parameters such as root-mean-square error (RMSE) and correlation coefficient between real and desired outputs (R). The results of both methods indicate that factors such as the transmissivity of aquifer formations, GPMs drawdown, topography (the height of the well site on the level of the watershed), the groundwater exploitation values at the maximum operating radius of the well, and the distance from water resources are the main factors of GPMs drawdown. But the effectiveness of ANN in estimating GPMs drawdown is higher than the MLR method. The implemented methodology could be generalized to other watersheds with water scarcity problems for groundwater management.
EN
A method of creating a constitutive model of layered rocks based on an artificial neural network (ANN) is reported in this work. The ANN gives an implicit constitutive function Ʃⁿ⁺¹= F( Ʃⁿ , ΔE), relating the new state of homogenized stresses Ʃⁿ⁺¹ with the old state Ʃⁿ and with the increment of homogenized strains ΔƩ. The first step is to repeatedly run a strain- controlled homogenisation on an uni-dimensional finite element model of a periodic cell with elastic-plastic models (Drucker-Prager) of the components. Paths are created in (Ʃ, E) space, from which, a set of patterns is formed to train the ANN. A description of how to prepare this data and a discussion on ANN training issues are presented. Finally, the procedure based on trained ANN is put into a finite-element code (ZSoil.PC) as a user-delivered constitutive function. The approach is verified by comparing the results of the developed model basing on ANN with a direct (single-scale) analysis, which showed acceptable accuracy.
PL
W niniejszym artykule zaproponowano system do automatycznego rozpoznawania zwierząt na obrazach z nagrań wideorejestratorów samochodowych wykorzystujący sztuczne sieci neuronowe. Na przygotowanej bazie obrazów przeprowadzono trening, walidację i testy pod kątem rozpoznawania m.in. krów, dzików, saren oraz innych, także mniejszych, zwierząt spotykanych na polskich drogach. Osiągnięto satysfakcjonujące wyniki rozpoznawania nawet na obrazach o niskiej jakości. Do obsługi systemu przygotowano aplikację użytkownika umożliwiającą przeprowadzenie testów rozpoznawania na pojedynczych zdjęciach i plikach wideo.
EN
This article proposes a system for automatic recognition of animals based on images from car video recorders using artificial neural net works. Training, validation and tests were conducted on the prepared image database in terms of recognizing, among others: cows, wild boars, roe deer and other, also smaller, animals encountered on Polish roads. Satisfactory recognition results were achieved even on low-quality image frames. A user application has been prepared to operate the system, enabling recognition tests to be conducted on photos and video files.
EN
Since the generalization of the use of electricity, energy consumption, conversion and energy storage has led to research and development of new sources of supply. This interest has increased due to the depletion of fossil fuels, their impact on the environment and the waste they generate. Photovoltaic (PV) technology is an attractive solution as a replacement or complementary to conventional sources of electricity supply due to its many advantages. This work focuses on studying, modeling and designing of an advanced controller for a step up converter that uses an artificial neural network (ANN) as a maximum power point tracking (MPPT) algorithm to generate maximum power. The effectiveness was proved for climatic conditions variation. A comparative study between the proposed method and the conventional ones was carried out using Matlab/Simulink software.
PL
Od czasu uogólnienia wykorzystania energii elektrycznej jej zużycie, konwersja i magazynowanie energii doprowadziły do badań i rozwoju nowych źródeł zaopatrzenia. Zainteresowanie to wzrosło ze względu na wyczerpywanie się paliw kopalnych, ich wpływ na środowisko i generowane przez nie odpady. Technologia fotowoltaiczna (PV) jest atrakcyjnym rozwiązaniem jako zamiennik lub uzupełnienie konwencjonalnych źródeł zaopatrzenia w energię elektryczną ze względu na swoje liczne zalety. Praca ta koncentruje się na badaniu, modelowaniu i projektowaniu zaawansowanego sterownika do przetwornicy podwyższającej, która wykorzystuje sztuczną sieć neuronową (ANN) jako algorytm śledzenia punktu mocy maksymalnej (MPPT) do generowania maksymalnej mocy. Skuteczność została wykazana przy zmienności warunków klimatycznych. Badanie porównawcze proponowanej metody z metodami konwencjonalnymi przeprowadzono z wykorzystaniem oprogramowania Matlab/Simulink.
EN
Artificial intelligence is poised to revolutionise the energy sector. Its data-based learning capabilities enable both energy production and consumption optimization. Energy needs are better assessed to support the energy transition. This digital innovation is necessary to implement the development policies for preserving the environment. There are many projects in this direction. They concern the oil industry as well as gas extraction or the intelligence of electrical networks. In fact, artificial intelligence is gradually becoming the tool that optimizes energy production and consumption.
PL
Sztuczna inteligencja może zrewolucjonizować sektor energetyczny. Jego możliwości uczenia się w oparciu o dane umożliwiają zarówno optymalizację produkcji energii, jak i jej zużycia. Potrzeby energetyczne są lepiej oceniane, aby wesprzeć transformację energetyczną. Ta cyfrowa innowacja jest niezbędna do realizacji polityki rozwoju na rzecz ochrony środowiska. Projektów w tym kierunku jest wiele. Dotyczą one zarówno przemysłu naftowego, jak i wydobycia gazu czy inteligencji sieci elektrycznych. W rzeczywistości sztuczna inteligencja stopniowo staje się narzędziem optymalizującym produkcję i zużycie energii.
EN
The article presents issues related to the possibility of using an artificial neural network to classify factors describing the lightning hazard. It also analyzed the selection of the most optimal type of neural network for this type of task, as well asthe issue of input data, which both teach the neural network and form the basis for the final classification. Finally, the conclusions and assumptions necessary for the practical implementation of the task were drawn. The practical part of the task is planned as the following consideration stage.
PL
W artykule została przedstawiona problematyka związana z możliwością wykorzystania sztucznej sieci neuronowej do przeprowadzenia klasyfikacji współczynników opisujących zagrożenie piorunowe. Przeanalizowano wybór najbardziej optymalnego rodzaju sieci neuronowej dla tego rodzaju zadania, a także kwestię danych wejściowych, które posłużą zarówno do uczenia sieci neuronowej, jak również stanowią podstawę do końcowej klasyfikacji. Na koniec wyciągnięte zostały wnioski oraz założenia niezbędne do praktycznej realizacji zadania. Praktyczna część zadania będzie stanowić kolejny etap rozważań.
EN
The crisis that the general public is worried about is particulate matter as small as 2.5 microns, which is invisible to the naked eye, causing a great lack of awareness of health hazards. One of the key goals and visions of government leaders around the world is to tackle PM2.5 particulate matter, but without measurements, reports and predictions, how will it lead to emission reduction and remedial steps? Therefore, the prediction of PM2.5 is considered as the main factor that will help to reduce the pollution of PM2.5. So, Neural networks have been widely used in predictive research, but the problem is What type of neural network would be most suitable for predicting the value of PM2.5? In this research, the predictions were compared between Artificial Neural Network (ANN) and Long Short -Term Memory (LSTM) using values measured from the performance test results with accuracy. The results showed that when the values of similar hyperparameters were given different results, the average ANN accuracy is 91.1460%. The average accuracy LSTM is 96.8496%. The values obtained from the comparison clearly show that for the prediction of PM2.5, the LSTM neural network was significantly more suitable than the ANN neural network.
PL
Kryzys, który niepokoi opinię publiczną, to pył zawieszony o wielkości zaledwie 2,5 mikrona, który jest niewidoczny gołym okiem, powodując ogromny brak świadomości zagrożeń dla zdrowia. Jednym z kluczowych celów i wizji przywódców rządów na całym świecie jest rozwiązanie problemu pyłu zawieszonego PM2,5, ale bez pomiarów, raportów i prognoz, w jaki sposób doprowadzi to do redukcji emisji i działań zaradczych? Dlatego prognoza PM2,5 jest uważana za główny czynnik, który pomoże zmniejszyć zanieczyszczenie PM2,5. Tak więc sieci neuronowe były szeroko stosowane w badaniach predykcyjnych, ale problem polega na tym, jaki typ sieci neuronowej byłby najbardziej odpowiedni do przewidywania wartości PM2,5? W tym badaniu porównano przewidywania między sztuczną siecią neuronową (ANN) a pamięcią długokrótkoterminową (LSTM) przy użyciu wartości zmierzonych z wynikami testu wydajności z dużą dokładnością. Wyniki pokazały, że przy różnych wartościach podobnych hiperparametrów średnia dokładność ANN wynosi 91,1460%. Średnia dokładność LSTM wynosi 96,8496%. Uzyskane z porównania wartości jednoznacznie wskazują, że do predykcji PM2,5 sieć neuronowa LSTM okazała się znacznie bardziej odpowiednia niż sieć neuronowa ANN.
13
Content available remote Autonomiczna kamera do wykrywania wolnych miejsc parkingowych
PL
W artykule została opisana architektura systemu autonomicznej kamery do wykrywania wolnych miejsc parkingowych. System został zrealizowany i przetestowany zarówno w warunkach laboratoryjnych, jak i rzeczywistych. Omówione zostały kluczowe elementy systemu, ich współdziałanie, a także możliwości modyfikacji i rozwoju.
EN
The article describes the architecture of an autonomous camera system to detect free parking spaces. The system was implemented and tested both in laboratory and real conditions. The key elements of the system, their interaction, as well as the possibilities of modification and development were discussed.
14
Content available remote Automatyczne rozpoznawanie pojazdów uprzywilejowanych
PL
W niniejszym artykule zaprezentowano system do automatycznego rozpoznawania pojazdów uprzywilejowanych występujących na terenie Polski, działający na podstawie analizy obrazów i wykorzystujący sztuczne sieci neuronowe. Przygotowano bazę obrazów do przeprowadze nia skuteczności klasyfikacji wybranych rodzajów pojazdów uprzywilejowanych, z uwzględnieniem ich gabarytów i możliwości wykrywania sygnałów świetlnych. Dla najlepszej konfiguracji przebadanych sieci neuronowych i rozdzielczości obrazów osiągnięto ponad 99% dokładność klasyfikacji.
EN
This article presents a system for automatic recognition of emergency vehicles in Poland, using artificial neural networks and image anal ysis. A database of images was prepared to carry out the classification tests of selected types of emergency vehicles, taking into account their di mensions and the ability to detect light signals. For the best configuration of the tested neural networks and image resolution, over 99% classification accuracy was achieved.
EN
Accurate information on Young’s modulus (E) is required for simulating rock deformation in mines; on the other hand, it is very cumbersome to obtain in the laboratory and collecting drilled cores in sufficient amounts, especially in the case of soft rocks, is quite impossible. Empirical equations were deducted for - from easily determinable rock properties, and the final model was selected through different statistical strength parameter tests. The generalization of the equation was verified through the normal distribution tests of residues of the equation. R2 came to be 0.609 and was validated using an artificial neural network with an improved value of 0.73.
EN
Identifying and assessing Parkinson's disease in its early stages is critical to effectively monitoring the disease's progression. Methodologies based on machine learning enhanced speech analysis are gaining popularity as the potential of this field is revealed. Acoustic features, in particular, are used in a variety of algorithms for machine learning and could serve as indicators of the general health of subjects' voices. In this research paper, a novel method is introduced for the automated detection of Parkinson's disease through speech signal analysis, a support vector machines classifier (SVM) and an Artificial Neural Network (ANN) are used to evaluate and classify the data based on two acoustic features: Bark Frequency Cepstral Coefficients (BFCC) and Mel Frequency Cepstral Coefficients (MFCC). These features are extracted from the denoised signals using Empirical Mode Decomposition (EMD). The most relevant results obtained for a dataset of 38 participants are by the BFCC coefficients with an accuracy up to 92.10%. These results confirm that EMD-BFCC-SVM method can contribute to the detection of Parkinson's disease.
EN
The wind energy conversion systems (WECS) suffer from an intermittent nature of source (wind) and the resulting disparity between power generation and electricity demand. Thus, WECS are required to be operated at maximum power point (MPP). This research paper addresses a sophisticated MPP tracking (MPPT) strategy to ensure optimum (maximum) power out of the WECS despite environmental (wind) variations. This study considers a WECS (fixed pitch, 3KW, variable speed) coupled with a permanent magnet synchronous generator (PMSG) and proposes three sliding mode control (SMC) based MPPT schemes, a conventional first order SMC (FOSMC), an integral back-stepping-based SMC (IBSMC) and a super-twisting reachability-based SMC, for maximizing the power output. However, the efficacy of MPPT/control schemes rely on availability of system parameters especially, uncertain/nonlinear dynamics and aerodynamic terms, which are not commonly accessible in practice. As a remedy, an off-line artificial function-fitting neural network (ANN) based on Levenberg-Marquardt algorithm is employed to enhance the performance and robustness of MPPT/control scheme by effectively imitating the uncertain/nonlinear drift terms in the control input pathways. Furthermore, the speed and missing derivative of a generator shaft are determined using a high-gain observer (HGO). Finally, a comparison is made among the stated strategies subjected to stochastic and deterministic wind speed profiles. Extensive MATLAB/Simulink simulations assess the effectiveness of the suggested approaches.
EN
Biological treatment in wastewater treatment plants appears to be one of the most crucial factors in water quality management and planning. Though, measuring this important factor is challenging, and obtaining reliable results requires signifi cant eff ort. However, the use of artifi cial neural network (ANN) modeling can help to more reliably and cost-effectively monitor the pollutant characteristics of wastewater treatment plants and regulate the processing of these pollutants. To create an artifi cial neural network model, a study of the Samsun Eastern Advanced Biological WWTP was carried out. It provides a laboratory simulation and prediction option for flexible treatment process simulations. The models were created to forecast influent features that would affect effluent quality metrics. For ANN models, the correlation coefficients R-TRAINING and R-ALL are more than 0.8080. The MSE, RMSE, and MAPE were less than 0.8704. The model’s results showed compliance with the permitted wastewater quality standards set forth in the Turkish water pollution control law for the environment where the treated wastewater is discharged. This is a useful tool for plant management to enhance the quality of the treatment while enhancing the facility’s dependability and efficiency.
EN
In this study, artificial neural networks were used to predict the plastic flow behaviour of S355 steel in the process of high-temperature deformation. The aim of the studies was to develop a model of changes in stress as a function of strain, strain rate and temperature, necessary to build an advanced numerical model of the soft-reduction process. The high-temperature characteristics of the tested steel were determined with a Gleeble 3800 thermo-mechanical simulator. Tests were carried out in the temperature range of 400-1450 °C for two strain rates, i.e. 0.05 and 1 s-1. The test results were next used to develop and verify a rheological model based on artificial neural networks (ANNs). The conducted studies show that the selected models offer high accuracy in predicting the high-temperature flow behaviour of S355 steel and can be successfully used in numerical modelling of the soft-reduction process.
EN
The paper present the research concerning the value of the electric component of the electromagnetic (EM) energy determined by NHT3DL meter by Microrad with the 01E measuring probe during flight of Robinson R44 Raven helicopter. The point of reference for the recorded measurement was the normative limits of the electromagnetic field (EMF), which can influence a pilot in the course of a flight. Selected studies of the maximum value recorded by the meter was E = 7.68 V/m when landing at an airfield equipped with the VHF (Very High Frequency) omnidirectional radio range (VOR) approach system. The developed model of neural networks is used to predict the value of electric field exposure in the context of flight safety analysis.
PL
W artykule przedstawiono badania dotyczące wartości składowej elektrycznej energii elektromagnetycznej (EM) wyznaczonej miernikiem NHT3DL firmy Microrad z sondą pomiarową 01E podczas lotu śmigłowca Robinson R44 Raven. Punktem odniesienia dla zarejestrowanego pomiaru były granice normatywne pola elektromagnetycznego (PEM), które może oddziaływać na pilota w trakcie lotu. W wybranych pomiarach maksymalna wartość zarejestrowana przez miernik wynosiła E = 7.68 V/m podczas lądowania na lotnisku wyposażonym w system podejścia dookólnego VHF (Very High Frequency) -VOR. Opracowany model sieci neuronowych służy do przewidywania wartości ekspozycji pola elektrycznego w kontekście analizy bezpieczenstwa lotów.
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