Ograniczanie wyników
Czasopisma help
Autorzy help
Lata help
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 396

Liczba wyników na stronie
first rewind previous Strona / 20 next fast forward last
Wyniki wyszukiwania
Wyszukiwano:
w słowach kluczowych:  algorithm
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 20 next fast forward last
EN
In the article, the problem of detecting a suspicious object in the control by unmanned air vehicle (UAV) and tracking it by reaching and changing its direction in the shortest period of time is explored. To solve this optimal control problem, it is considered that the flight of UAV is described with simple motion equations. In the beginning, known quantities are current coordinates and speed of UAV, equation of motion of detected suspicious object.
EN
In recent years, 'weather routing' has been attracting increasing attention as a means of reducing costs and environmental impact. In order to achieve high-quality weather routing, it is important to accurately predict the ship's speed through ground during a voyage from ship control variables and predicted data on weather and sea conditions. Because sea condition forecasts are difficult to produce in-house, external data is often used, but there is a problem that the accuracy of sea condition forecasts is not sufficient and it is impossible to improve the accuracy of the forecasts because the data is external. In this study, we propose a machine learning method for predicting speed through ground by considering the actual values of the previous voyage’s drift speed for ships that regularly operate on the same route, such as ferries. Experimental results showed that this method improves the prediction performance of ship’s speed through ground.
EN
This article presents an in-depth analysis of the stress-deformation state (SDS) in the bottom structure of a semi-trailer truck body. Engineering analysis was conducted utilizing the SolidWorks software, focusing on a comprehensive CAD model of the semi-trailer truck body. The study explored variations in SDS parameters resulting from alterations in the geometric parameters of the body bottom elements. The research investigated alterations in static stress and displacement relative to changes in the proportions of the cross-section of the channel while maintaining fixed geometric dimensions of the workpiece, thickness of the workpiece, and the material of the body bottom. Graphical representations were generated to illustrate the variations in static stress, displacement, and safety margin concerning the thickness of the shelf and channel. Additionally, dependencies were derived that correlate static stresses in the channel with the thickness of the channel wall and the thickness of the body bottom sheet. The study results were compiled and summarized, offering valuable insights into the stress-deformation state of the semi-trailer truck body's bottom. Furthermore, machine learning techniques, specifically the RandomForest algorithm, were implemented in a Python environment to predict changes in static stress based on various factors. The model's predictions were validated by comparing predicted static stress values with actual values on a test sample. These findings facilitate efficient selection of appropriately sized elements by predicting static stress values, employing the RandomForest machine learning algorithm.
EN
In today’s manufacturing systems, especially in Industry 4.0, highly autonomous production cells play an important role. To reach this goal of autonomy, different technologies like industrial robots, machine tools, and automated guided vehicles (AGV) are deployed simultaneously which creates numerous challenges on various automation levels. One of those challenges regards the scheduling of all applied resources and their corresponding tasks. Combining data from a real production environment and Constraint Programming (CP-SAT), we provide a cascaded scheduling approach that plans production orders for machine tools to minimize makespan and tool changeover time while enabling the corresponding robot for robot-collaborated processes. Simultaneously, AGVs provide all production cells with the necessary material and tools. Hereby, magazine capacity for raw material as well as finished parts and tool service life are taken into account.
EN
Understanding the impact of power harmonic on energy transmission play an important role not only in the operation process but also in the designing procedure of MV grid. In 6kV mining grids of Vietnamese coal mines, because of rapidly utilizing the power electronic machines, the power quality violation occurs very frequently. This lead to many disadvantages such as: the increase of power losses, voltage distortion, over-heating in transformers and conductors. Moreover, the presence of power harmonic bring the bad impact of skin effect and proximity on conductor including overhead-conductors and cables. The actual operation exhibits that the losses of transmission lines are approximately over 50% of total network losses. If there are power quality violation, this amount could be higher. Basing on investigating the fact of power harmonic violations in 6kV grid of both underground and surface mines, the paper will analyze this kind of impact. An algorithm relying on Matlab programming is used to calculate the energy losses. Results are compared with on-site measurement datas and lab-measurement to obtain series of correction factors corresponding to individual line’s cross section. The outcomes of research could be applicable for power utilities to have better analysis in the designing stage of mining MV grids.
EN
The subject of the research is modeling and analysisof the characteristics of multichannel and multi-node computer networks with priority services. The work is devoted to the study of the qualitative indicators of the functioning of computer networks with priority service.In this work, mathematical modelsare developed that make it possible to assess the quality of functioning of modern computer networks, taking into account thenumber of channels, waiting places in network nodes and the number of network nodes. The proposed methods for calculating the probability of failures andthe probability of timely delivery of a stream of requests make it possible to determine the real values of the qualitative indicators of the functioningof computer networks and are suitable for both designed and operating computer networks. The proposed technique makes it possible to determinethe number of packets in the queue and the optimal amount of buffer memory in computer network nodes.
PL
Przedmiotem badań jest modelowanie i analiza charakterystyk wielokanałowych i wielowęzłowych sieci komputerowych z usługami priorytetowymi. Praca poświęcona jest badaniu jakościowych wskaźników funkcjonowania sieci komputerowych z usługami priorytetowymi. W pracy opracowano modele matematyczne umożliwiające ocenę jakości funkcjonowania nowoczesnych sieci komputerowych z uwzględnieniem liczby kanałów, miejsc oczekiwania w węzłach sieci oraz liczby węzłów sieci. Proponowane metody obliczania prawdopodobieństwa awarii i prawdopodobieństwa terminowego dostarczenia strumienia żądań umożliwiają określenie rzeczywistych wartości wskaźników jakościowych funkcjonowania sieci komputerowych i są odpowiednie zarówno dla projektowanych, jak i działających sieci komputerowych. Proponowana technika umożliwia określenie liczby pakietów w kolejce i optymalnej ilości pamięci buforowej w węzłach sieci komputerowej.
EN
This study aims to examine the water quality of Lake Sentani using both in-situ data and satellite remote sensing data. In-situ data was taken in July 2023 at 18 sampling sites, including temperature, DO, pH, TDS, and water transparency. In-situ data is also used to develop and validate algorithms for estimating water quality from satellite remote sensing data. Multi-temporal Landsat-8 satellite imagery was used to spatially and temporally map the surface water quality of Lake Sentani. In-situ data showed temperature, DO, pH, TDS, and water transparency ranging from 29.3°C to 31.8°C, 1.7 mg/L to 7.9 mg/L, 7.75 to 8.64, 23 mg/L to 46 mg/L, and 2.28 m to 2.94 m, respectively. Only water transparency does not meet the quality standards for water quality (class 1 and class 2), while the other parameters meet class 1 to class 3 quality standards for surface water samples. The accuracy of the algorithm used and the resulting one has a low Mean Absolute Error value, namely 0.81 (temperature), 0.37 (DO), 4.84 (TDS), and 0.12 (water transparency). The temperature and TDS concentrations from the satellite imagery data ranged from 28.110°C to 33.918°C, and 7.829 mg/L to 102.702 mg/L, respectively. Both of these parameters still meet water quality standards. The DO concentrations ranged from 2.228 mg/L to 12.562 mg/L, and water transparency ranged from 0.424 m to 3.151 m. The concentration of DO and water transparency do not meet quality standards in several parts of Lake Sentani, especially in November and August.
EN
In this paper three algorithms of motion planning for two-input, one-chained nonholonomic systems are presented. The classical Murray-Sastry algorithm is compared with two original algorithms aimed at optimizing energy of controls. Based on the generalized Campbell- Baker-Hausdorff-Dynkin formula applied to the systems, some observations are made concerning the optimal relationship between amplitudes and phases of harmonic controls. The observations help to optimize a selection of controls and to design new algorithms for planning a sub- optimal trajectory between given boundary configurations. It was also shown that for those particular systems the generalized C-B-H-D formula is valid not only locally (as in a typical case) but also globally. Simulations performed on the five-dimensional chain system facilitate distinguishing the proposed algorithms from the Murray-Sastry algorithm and to illustrate their features. Systems in a chained form are important from a practical point of view as they are canonical for a class of systems transformable into this form. The most prominent among them are mobile robots with or without trailers.
EN
In view of the high cost and difficulty of ensuring the accuracy in the measurement of fire smoke velocity, the measurement system developed using platinum resistance temperature detectors and an 8-bit microcontroller, is used to realize the fast measurement of high-temperature fire smoke velocity. The system is based on the thermodynamic method and adopts the Kalman filter algorithm to process the measurement data, so as to eliminate noise and interference, and reduce measurement error. The experimental results show that the Kalman filter algorithm can effectively improve the measurement accuracy of fire smoke velocity. It is also shown that the system has high measurement accuracy, short reaction time, low cost, and is characterized by high performance in the measurement of high-temperature smoke velocity in experiments and practice.
EN
The aim of this paper is to present a new method for generating random pairwise comparison matrices with a given inconsistency ratio (CR) interval using inconsistency reduction algorithms. Pairwise comparison (PC) is a popular technique for multi-criteria decision-making, its purpose is to assign weights to the compared entities, thus ranking them from best to worst. The presented method combines the traditional random generation of comparison matrices supported by inconsistency reduction algorithms: the “Xu and Wei” algorithm and the “Szybowski” algorithm. This paper presents research that shows an increase in performance when generating such matrices relative to the standard random comparison matrix generation procedure using the “Szybowski” algorithm. The other algorithms also improve the process, but to a lesser extent, making the “Szybowski” supporting algorithm the preferred solution for the new process. As a result of the research, a free online tool “PC MATRICES GENERATOR” has also been made available to efficiently generate a large number of comparison matrices with a given CR factor range, any matrix size, and any number of matrices, enabling much more efficient and less time-consuming research in many fields that use comparison matrices, as the analytic hierarchy/network process (AHP/ANP), ELECTREE, PAPRIKA, PROMETHE, VIKOR or the Best-Worst method (BWM).
EN
This paper presents a new approach for searching the most favourable mechanical assembly sequence. The proposed method is described and its basic modules are presented. The concept is based on the assumption that the method should help the engineer in specifying the best assembly sequence with the short possible time calculation, taking into account the principles of design for assembly at an early stage of development of the product design. The algorithm for generating an accurate assembly sequence was described in detail and its application on real-life example was presented.
PL
Zwiększone zapotrzebowanie na energię elektryczną spowodowane przewidywaną popularyzacją pojazdów elektrycznych może zagrozić bezpiecznej i ekonomicznej pracy sieci elektroenergetycznej. Z tego względu niezbędne są odpowiednie strategie ładowania pojazdów. Skoordynowane systemy ładowania pojazdów mogą być realizowane jako systemy scentralizowane, zdecentralizowane i hierarchiczne. W artykule skupiono się na celach i ograniczeniach dotyczących projektowania algorytmów sterowania ładowaniem.
EN
The increased demand for electricity due to the anticipated popularisation of electric vehicles (EVs) may threaten the safe and economic operation of the electrical grid. Therefore, appropriate EV charging strategies will be necessary. Coordinated EV charging systems might be implemented as centralized, decentralized and hierarchical systems. This paper focuses on the objectives and constraints for the design of charging control algorithms.
EN
The paper analyzes the main methods for determining the homogeneity of fine dispersed mixtures, as a result of which it has been found that all of them are characterized by significant complexity and low implementation rate. There has been developed a highly effective photoanalytical method for assessing homogeneity, which is based on software analysis of digital photo cross-cut of the mixture and determining the degree of its homogeneity based on comparison of the obtained color identifiers with the values of the reference database.
PL
W pracy przeanalizowano główne metody określania jednorodności drobno zdyspergowanych mieszanin, w wyniku czego stwierdzono, że wszystkie charakteryzują się dużą złożonością i niskim stopniem wdrożenia. Opracowano wysoce efektywną fotoanalityczną metodę oceny jednorodności, która opiera się na programowej analizie cyfrowego fotoprzekroju mieszaniny i określeniu stopnia jej jednorodności na podstawie porównania otrzymanych identyfikatorów barw z wartościami bazy referencyjnej.
EN
The revitalization of mining dumps in the Silesian agglomeration is a very difficult and complex problem. It has a substantial impact on the concepts of sustainable urban development. Other than the key areas including people, the environment and the economy, revitalization also refers to spatial management, and thus to a significant improvement in the functioning conditions of the local cities’ communities. The article describes an algorithm assessing the possibilities of revitalizing a mining dump by one of the Polska Grupa Górnicza’s mines. With legal status and location taken into account, several potential scenarios had been proposed, out of which one was chosen based on the adopted criteria. The chosen scenario had been subjected to further assessment using analyses such as SWOT/TOWS, FMEA, and QFD. The analyses had been carried out in order to acquire more effective and meaningful assessments, having taken social and economic aspects into consideration. In effect of the carried out analysis a recreational scenario was proposed. The adopted solution shows that the mine can continue its work in accordance with the principle of sustainable development as well as apply the concept of corporate social responsibility.
EN
The article presents the method of identifying surface damage by measuring changes in resistance in graphite-based sensing skin. The research focused on analysis of conductivity anomalies caused by surface damage. Sensitivity maps obtained with Finite Element Method (FEM) in conjunction with the analytical damage model were used to build the coating evaluation algorithm. The experiment confirmed the ability of this method to identify a single elliptical-shape damage. Eight electrodes were enough to locate the damage that covered about 0.1‰ of the examined area. The proposed algorithm can prove useful in simple applications for surface condition monitoring. It can be implemented wherever it is possible to apply a thin layer of conductor to a non-conductive surface.
EN
A collision avoidance algorithm applicable in simultaneous localization and mapping (SLAM) has been developed with a prospect of an on-line application for mobile platforms to search and map the operation area and avoid contact with obstacles. The algorithm, which was implemented in MATLAB software, is based on a linear discrete-time state transition model for determination of the platform position and orientation, and a ‘force’ points method for collision avoidance and definition of the next-step of platform motion. The proposed approach may be incorporated into real-time applications with limited on-board computational resources.
EN
The paper regards the urgency of creating small - sized systems for automated local sorting of household waste for modern residential complexes based on visual spectrometry. For this purpose, algorithms for system operation were developed and the procedure for designing a functional control scheme for the sorting process with the construction of the necessary contours of automated control was presented.
PL
Artykuł dotyczy pilną potrzebę stworzenia małogabarytowych systemów zautomatyzowanego lokalnego sortowania odpadów komunalnych dla nowoczesnych zespołów mieszkaniowych w oparciu o spektrometrię wizualną. W tym celu opracowano algorytmy pracy systemu oraz przedstawiono procedurę projektowania schematu funkcjonalnego sterowania procesem sortowania wraz z budową niezbędnych obwodów automatycznego sterowania. Przeprowadzono również analizę zastosowania modelu do oceny niezawodności zautomatyzowanego systemu sortowania odpadów.
EN
The basic parallel versions of the Danish Eulerian Model (UNI-DEM) has been implemented on the new petascale supercomputer DISCOVERER, installed last year in Sofia, Bulgaria by the company Atos. DISCOVERER is part of the European High Performance Computing Joint Undertaking (EuroHPC), which is building a network of 8 powerful supercomputers across the European Union (3 pre-exascale and 5 petascale).The results of some scalability experiments with the basic MPI and a hybrid MPI-OpenMP parallel implementations of UNI-DEM on the new Bulgarian petascale supercomputer DISCOVERER (in EuroHPC network) are presented here. They are compared with similar earlier experiments performed on the Mare Nostrum III supercomputer (petascale too) at Barcelona Supercomputing Centre - the most powerful supercomputer in Spain by that time, upgraded currently to the pre-exascale Mare Nostrum V, also part of the EuroHPC JU infrastructure.
EN
Using drones in groups in the military field is not a novel idea. A massive attack by a large amount of equipment is known to be very difficult to prevent. Therefore, it is a good tactic to sacrifice some of the relatively cheap drones to destroy special enemy targets in a massive attack. This raises the issue of joint control of the behaviour of a group of drones. This paper proposes a System of Systems ideology-based decision-making system that allows to individually control each drone in a group flight. An algorithm is developed that allows controlling drones by controlling their speed.
PL
W artykule opisano metodę analizy obszarów inwestycyjnych, mającą na celu prezentację docelowych wskaźników urbanistyczno-architektonicznych. Przedstawiono wiele statystyk ukazujących obecny stan inwestycji budowlanych w porównaniu do innych państw Unii Europejskiej oraz do wartości uśrednionych. Zaproponowano zmianę sposobu obliczenia parametrów z obecnej, bazującej na współczynnikach z powierzchni terenu, na obliczenia za podstawę obierające zagęszczenie planowanej liczby mieszkańców. Metodę przeanalizowano na podstawie obszaru Ogrodów Sukienniczych w Łodzi.
EN
The article describes the method of analyzing investment areas aimed at presenting the target urban and architectural parameters. A number of statistics were presented showing the current state of construction investments in comparison to other European Union countries and to averaged values. It was proposed to change the method of calculating the coefficients from the current one, based on the coefficients of the land surface, to the calculation based on the planned population density. The method was tested on the basis of the Ogrody Sukiennicze area in Łódź.
first rewind previous Strona / 20 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.