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Wyszukujesz frazę "parameters optimization" wg kryterium: Wszystkie pola


Tytuł:
Stochastic schemata exploiter-based optimization of hyper-parameters for XGBoost
Autorzy:
Makino, Hiroya
Kita, Eisuke
Powiązania:
https://bibliotekanauki.pl/articles/38707755.pdf
Data publikacji:
2024
Wydawca:
Instytut Podstawowych Problemów Techniki PAN
Tematy:
evolutionary computation
Stochastic Schemata Exploiter
hyperparameter optimization
XGBoost
obliczenia ewolucyjne
eksplorator schematów stochastycznych
optymalizacja hiperparametrów
Opis:
XGBoost is well-known as an open-source software library that provides a regularizing gradient boosting framework. Although it is widely used in the machine learning field, its performance depends on the determination of hyper-parameters. This study focuses on the optimization algorithm for hyper-parameters of XGBoost by using Stochastic Schemata Exploiter (SSE). SSE, which is one of Evolutionary Algorithms, is successfully applied to combinatorial optimization problems. SSE is applied for optimizing hyper-parameters of XGBoost in this study. The original SSE algorithm is modified for hyper-parameter optimization. When comparing SSE with a simple Genetic Algorithm, there are two interesting features: quick convergence and a small number of control parameters. The proposed algorithm is compared with other hyper-parameter optimization algorithms such as Gradient Boosted Regression Trees (GBRT), Tree-structured Parzen Estimator (TPE), Covariance Matrix Adaptation Evolution Strategy (CMA-ES), and Random Search in order to confirm its validity. The numerical results show that SSE has a good convergence property, even with fewer control parameters than other methods.
Źródło:
Computer Assisted Methods in Engineering and Science; 2024, 31, 1; 113-132
2299-3649
Pojawia się w:
Computer Assisted Methods in Engineering and Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Chromium Ions Removal by Capacitive Deionization Process: Optimization of the Operating Parameters with Response Surface Methodology
Autorzy:
Issa, Zainab M.
Salman, Rasha H.
Powiązania:
https://bibliotekanauki.pl/articles/2202352.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
capacitive deionization
electrosorption
carbon fibre
chromium
wastewater
Opis:
An innovative desalination method called electrosorption or capacitive deionization (CDI) has significant benefits for wastewater treatment. This process is performed by using a carbon fiber electrode as a working electrode to remove hexavalent chromium ions from an aqueous solution. The pH, NaCl concentration, and cell voltage were optimized using the Box-Behnken experimental design (BDD) in response surface methodology (RSM) to study the effects and interactions of selected variables. To attain the relationship between the process variables and chromium removal, the experimental data were subjected to an analysis of variance and fitted with a quadratic model. The optimum conditions to remove Cr(VI) ions were: pH of 2, a cell voltage of 4.3V, and NaCl concentration of 1.4 g/L. This study demonstrated that the carbon fiber electrode was very efficient in Cr(VI) ions removal and the BBD methodology was a practical and effective strategy for predicting the results of various experimental conditions during a CDI process for the removal of chromium ions.
Źródło:
Journal of Ecological Engineering; 2023, 24, 1; 51--65
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modified Hooke-Jeeves optimization of operating parameters for required slider speeds and displacements in a feeder slider-crank mechanism
Autorzy:
Sarigecili, Mehmet Ilteris
Akcali, Abrahim Deniz
Powiązania:
https://bibliotekanauki.pl/articles/27309875.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
slider-crank
dynamic model
speed control
Hooke-Jeeves method
optimization
suwak-korba
model dynamiczny
kontrola prędkości
Metoda Hooke’a-Jeevesa
optymalizacja
Opis:
In such applications as in the case of feeders in which a slider-crank mechanism equipped with a rotational spring on its crank is driven by a constant force and a lumped mass at the crank-connecting rod joint center, the slider is required to take on desired speeds and displacements. For this purpose, after obtaining and solving the dynamic model of the slider-crank mechanism, the output of this model is subjected to a modified Hooke-Jeeves method resulting in the development of a procedure for the optimization of selected set of operating parameters. The basic contribution involved in the so-called Hooke-Jeeves method is the procedure by which a cost-effective advancement towards a target optimum point is accomplished in a very short time. A user-friendly interface has also been constructed to support this procedure. The optimization procedure has been illustrated on a numerical example. The validation of the resulting dynamic model has also been demonstrated.
Źródło:
Archive of Mechanical Engineering; 2023, LXX, 1; 63--83
0004-0738
Pojawia się w:
Archive of Mechanical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimization of drilling parameters for aluminum metal matrix composite using entropy-weighted TOPSIS under MQL conditions
Autorzy:
Ghalme, Sachin G.
Karolczak, Paweł
Powiązania:
https://bibliotekanauki.pl/articles/38910718.pdf
Data publikacji:
2023
Wydawca:
Instytut Podstawowych Problemów Techniki PAN
Tematy:
Al metal matrix composite
drilling; parameter optimization
entropy weight
grey relational analysis
Opis:
The aim of the present work is to understand the effect of drilling parameters (drill speed and feed rate) during the drilling of a Saffil fiber-reinforced Al metal matrix composite (MMC) under minimum quantity lubrication (MQL) condition. The effect of drilling parameters on individual response characteristics is evaluated and the optimum drilling parameters are also investigated using a multi-response optimization technique known as the entropy-weighted technique for order performance by similarity to ideal solution (EWTOPSIS). The drilling parameter optimization is performed with the aim of minimizing surface roughness in the drilled hole, roundness error in the drilled hole and feed force during drilling. The drilling parameters have a significant effect on individual responses. Weights were assigned to each response using the entropy weight method, and closeness coefficients were calculated to obtain the optimal level for the drilling parameters. A drill speed of 11 m/min and a feed rate of 0.05 mm/rev are the optimal combination to minimize the desired output responses simultaneously.
Źródło:
Engineering Transactions; 2023, 71, 4; 595-616
0867-888X
Pojawia się w:
Engineering Transactions
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimization of geometric and flow parameters of solar air heater roughened with artificial roughness by Taguchi method
Autorzy:
Sahu, Mukesh Kumar
Mishra, Shivam
Kumar, Avinash
Powiązania:
https://bibliotekanauki.pl/articles/27312207.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
roughness
nusselt number
friction factor
Taguchi method
optimization
Opis:
The paper presents the investigation of the optimum design parameters of a solar air heater (SAH) having wire ribs as artificial roughness by using the Taguchi method. The solar air heater has arc shape roughness geometry with apex upstream flow on the absorber plate. The objective of this paper is to obtain a set of parameters that deliver maximum thermo-hydraulic performance. For this objective, a new parameter the thermo-hydraulic improvement parameter (ηTHIP), has been introduced. For the present analysis, the effects of Reynolds number (Re), relative roughness pitch (P/e), angle of attack (α), and relative roughness height (e/Dh), denoted by A, B, C, and D, respectively, have been considered. An (L18 = 61 · 3 2 ) orthogonal array (OA) was chosen as an experimental plan for applying the Taguchi method. The set of control factors for the solar air heater SAH which delivers the maximum Nusselt number (Nu), and minimum friction factor (fr) – are A6B2C2, and A1B1C3 respectively. To obtain the maximum THIP the experimental set-up requires only one single run using the parameter A6B2C2, hence there is no need to run it all 54 times.
Źródło:
Archives of Thermodynamics; 2023, 44, 3; 3--33
1231-0956
2083-6023
Pojawia się w:
Archives of Thermodynamics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimization of GTAW Process Parameters of Dissimilar Al-Mg Alloys for Enhanced Joint Strength - Taguchi Approach
Autorzy:
Antony Prabu, D.
Jayakumar, K.S.
Madhavan Pillai, Elangovan
Kumaresan, G.
Powiązania:
https://bibliotekanauki.pl/articles/27765105.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
AA5052-H32
AA5083-H111
mechanical properties
microstructures
optimization
tungsten inert gas welding
Opis:
The Tungsten Inert Gas (TIG) welding processes one of the prevalent methods used for welding aluminum alloys. TIG welding is most commonly used due to its superiority in welding less dense materials. The most prevalent issues encountered with TIG welding aluminium alloys are porosity creation and cracking due to solidification, both of which result in lower mechanical properties. Because of the metal’s susceptibility to heat input, this occurs. The current work is the result of a desire to improve the mechanical properties of dissimilar aluminium metals: AA5052-H32 & AA5083-H111. The process parameters of TIG welding are optimized towards eliminating the previously discussed failure scenarios. Various optimization techniques exist towards obtaining optimizing processes such as Response Surface Methodology (RSM), Genetic Algorithm (GA), Artificial Neutral Network (ANN), Flower pollination algorithm, Taguchi method etc, The Taguchi method was chosen for the optimization of process parameters due to its inherent nature of solving problems of singular variance. The optimal parameters combination was determined i.e. welding current at 170 A, filler rod diameter 2.4 mm and Gas flow rate of 11 lpm. The optimized input parameter was used to TIG weld the confirmation specimen which are further investigated for mechanical and metallurgical characterizations. The parameters were optimized and the results indicate that the input current was found to be the most contributing towards improving mechanical properties over all the process parameters.
Źródło:
Archives of Metallurgy and Materials; 2023, 68, 2; 599--606
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimization of parts cutting process parameters working in conditions of cyclic loads
Optymalizacja parametrów procesu cięcia części pracujących w warunkach obciążeń cyklicznych
Autorzy:
Barandych, Kateryna
Vysloukh, Sergii
Tymchyk, Grygoriy
Murashchenko, Oleksandr
Smailova, Saule
Kumargazhanova, Saule
Powiązania:
https://bibliotekanauki.pl/articles/27315447.pdf
Data publikacji:
2023
Wydawca:
Politechnika Lubelska. Wydawnictwo Politechniki Lubelskiej
Tematy:
technological support
fatigue life
finishing turning process
optimization
wsparcie technologiczne
trwałość zmęczeniowa
proces toczenia wykańczającego
optymalizacja
Opis:
The paper is devoted to questions of technological fatigue life assurance of parts working in conditions of cyclic loads by optimization their cutting conditions for finish turning process. In order to solve the task of optimizing the parts cutting conditions, the corresponding software, based on the previously created mathematical model of the finishing turning process, was developed in the C# programming language. With the purpose of technological providing the necessary fatigue life of the part, taking into account the real conditions of its operation for the maximum productivity of the finishing turning process, the methodical recommendations for determining the optimal parts cutting conditions at the phase of production technological preparation are given. An example application of the proposed solution is presented.
Artykuł poświęcony jest zagadnieniom zapewnienia technologicznej trwałości zmęczeniowej części pracujących w warunkach obciążeń cyklicznych, poprzez optymalizację ich warunków skrawania w procesie toczenia wykańczającego. W celu rozwiązania zadania optymalizacji warunków skrawania części, zostało opracowane odpowiednie oprogramowanie w języku C#, oparte na wcześniej stworzonym modelu matematycznym procesu toczenia wykańczającego. W celu technologicznego zapewnienia niezbędnej trwałości zmęczeniowej części, biorąc pod uwagę rzeczywiste warunki jej działania dla maksymalnej wydajności procesu toczenia wykańczającego, podano metodyczne zalecenia dotyczące określania optymalnych warunków skrawania części na etapie technologicznego przygotowania produkcji. Zaprezentowano przykładowe zastosowanie proponowanego rozwiązania.
Źródło:
Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska; 2023, 13, 3; 90--93
2083-0157
2391-6761
Pojawia się w:
Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimization of support parameters for reusable mining excavations based on a neuro-heuristic prognostic model
Autorzy:
Babets, Dmytro
Sdvyzhkova, Olena
Dyczko, Artur
Gliwiński, Łukasz
Powiązania:
https://bibliotekanauki.pl/articles/27324371.pdf
Data publikacji:
2023
Wydawca:
Instytut Techniki Górniczej KOMAG
Tematy:
longwall mining
coal seam
geomechanical processes
excavation reuse
jointed rocks
Finite Element Analysis
stress-strain analysis
support parameters
multifactorial analysis
nonlinear optimization
górnictwo
proces geomechaniczny
analiza
optymalizacja
Opis:
This publication delves into geomechanical processes encountered during sequential longwall mining of coal seams, with a unique focus on reusing the conveyor track of the prior longwall as the ventilation pathway for the subsequent longwall. An in-depth geomechanical rationale is provided for the reuse of excavations within jointed rock formations.To ascertain the critical roles played by various support and protective elements at each distinct mining stage, a comprehensive analysis is performed using finite element techniques to delineate thethree-dimensional stress-strain characteristics of the rock mass.Employing an innovative methodology integrating multifactorial analysis, contemporary structural identification algorithms, and a neuro-heuristic approach for predictive mathematical modeling, an integral stability metric for reusable mining excavations isintroduced. Specifically, this metric quantifies the relative preservation of theexcavation's cross-sectional area following its connection to thesecond longwall.Furthermore, the study tackles the challenge of nonlinear optimization through the application of the generalized reduced gradient method (Frank-Wolfe), ultimately deriving the optimal combination of factors that maximizes the preservation of the cross-sectional area for these reusable excavations.
Źródło:
Mining Machines; 2023, 41, 3; 200--211
2719-3306
Pojawia się w:
Mining Machines
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Parameter identification approach using improved teaching and learning based optimization for hub motor considering temperature rise
Autorzy:
Li, Yong
Wang, Yuan
Zhang, Taohua
Hu, Han
Wu, Hao
Powiązania:
https://bibliotekanauki.pl/articles/2203368.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
parameters identification
teaching–learning-based optimization
hub motor
temperature rise
Opis:
Temperature rise of the hub motor in distributed drive electric vehicles (DDEVs) under long-time and overload operating conditions brings parameter drift and degrades the performance of the motor. A novel online parameter identification method based on improved teaching-learning-based optimization (ITLBO) is proposed to estimate the stator resistance, -axis inductance, -axis inductance, and flux linkage of the hub motor with respect to temperature rise. The effect of temperature rise on the stator resistance, -axis inductance, -axis inductance, and magnetic flux linkage is analysed. The hub motor parameters are identified offline. The proposed ITLBO algorithm is introduced to estimate the parameters online. The Gaussian perturbation function is employed to optimize the TLBO algorithm and improve the identification speed and accuracy. The mechanisms of group learning and low-ranking elimination are established. After that, the proposed ITLBO algorithm for parameter identification is employed to identify the hub motor parameters online on the test bench. Compared with other parameter identification algorithms, both simulation and experimental results show the proposed ITLBO algorithm has rapid convergence and a higher convergence precision, by which the robustness of the algorithm is effectively verified.
Źródło:
Metrology and Measurement Systems; 2023, 30, 1; 99--115
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The vertical screw conveying characteristics of cohesive particle and optimization of design parameters
Autorzy:
Chen, Suifan
Zhang, Xiaomeng
Li, Qipeng
Shen, Ce
Shi, Yongchang
Powiązania:
https://bibliotekanauki.pl/articles/24200814.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
discrete element method
conveying characteristics
NSGA-II
comprehensive evaluation
Opis:
The purpose of this paper is to solve the problem of low conveying efficiency and serious blade wear during vertical screw conveying of cohesive particles. Firstly, the reliability of DEM simulation was verified by comparing the simulated and theoretical values and the influence regularity of different design parameters (rotational speed, pitch, and clearance) on screw conveying characteristics were analyzed based on DEM. In addition, the effect of design parameters on the screw conveying characteristics is identified by ANOVA. Then, the multi-objective optimization model with the both of maximizing the average mass flow rate and minimizing the maximum wear depth of the blade was established using the polynomial fitting regression, which was solved by the non-dominated sorting genetic algorithm (NSGA-II). Finally, the comprehensive evaluation was used to determine the best design parameters. The above research results provide a certain reference for the study of cohesive particle’s vertical screw conveying characteristics and equipment optimization design.
Źródło:
Eksploatacja i Niezawodność; 2023, 25, 1; art. no. 13
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new tooling approach for friction stir welding of thin sheet AA2024-T3 - optimization of welding parameters
Nowe podejście narzędziowe do zgrzewania tarciowego cienkich blach AA2024-T3 - optymalizacja parametrów zgrzewania
Autorzy:
Myśliwiec, Piotr
Powiązania:
https://bibliotekanauki.pl/articles/2204386.pdf
Data publikacji:
2022
Wydawca:
Politechnika Rzeszowska im. Ignacego Łukasiewicza. Oficyna Wydawnicza
Tematy:
aluminium alloy AA2024-T3
ANOVA
ceramic tools
friction stir welding
FSW tool geometry
joining of thin sheets
RSM
stop aluminium AA2024-T3
narzędzia ceramiczne
zgrzewanie tarciowe z przemieszaniem
gemetria narzędzia do zgrzewanie tarciowego z przemieszaniem
łączenie cienkich blach
Opis:
In this study a new ceramics tools with different groove distributions were designed and manufactured in order to enrich technological storage of joining thinwall structures and obtain sound joint with high quality of Alclad AA2024-T3 alloy of 0.5 mm in thickness. Four types of tools were tested, without grooves, with 1, 2 and 6 grooves. The tools are made of two materials. The straight shank is made from tungsten carbide and tool body made from ceramics strengthened with whiskers. The influence of technological parameters on the strength of FSW joints was tested by the Response Surface Methodology (RSM) and Analysis of Variance (ANOVA) method. The least durable weld is produced by a tool without grooves. The single and double flute tool produces a good quality weld over a wide range of tool speeds. It has been shown that the grooves on the tool shoulder significantly affect the quality of the obtained FSW joint.
W pracy zaprojektowano i wykonano nowe narzędzia ceramiczne o różnym rozkładzie rowków w celu wzbogacenia technologii łączenia konstrukcji cienkościennych i uzyskania wysokiej jakości połączenia blach ze stopu aluminium AA2024-T3 Alclad o grubości 0,5 mm. Przetestowano cztery typy narzędzi, bez rowków, z 1, 2 i 6 rowkami. Narzędzia wykonano z dwóch materiałów. Część chwytową wykonano z węglika wolframu, a korpus narzędzia z ceramiki wzmocnionej whiskerami. Wpływ parametrów technologicznych na wytrzymałość złączy FSW badano metodami analizy powierzchni odpowiedzi (RSM) oraz analizy wariancji (ANOVA). Najmniej trwałą spoinę wytworzyło narzędzie bez rowków. Narzędzie z pojedynczym i podwójnym rowkiem zapewniło dobrej jakości spoinę w szerokim zakresie prędkości obrotowych narzędzia. Wykazano, że rowki na kołnierzu narzędzia istotnie wpływają na jakość uzyskanego połączenia FSW.
Źródło:
Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika; 2022, z. 94; 37--50
0209-2689
2300-5211
Pojawia się w:
Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Design Of the Tension Mechanism Of a Knotter And Optimization Of the Motion Parameters
Autorzy:
Lan, Jiahao
Feng, Pei
Zhang, Junping
Zhang, Ronggen
Yang, Chongchang
Powiązania:
https://bibliotekanauki.pl/articles/2200745.pdf
Data publikacji:
2022
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:
chemical fiber
filament knotting process
knotter
catenary
knotting rate
Opis:
Currently, the knotting of chemical fiber filament packages in factories primarily comprises manual operations. It also has a high labor intensity and is subject to artificial subjective factors, due to which it is difficult to guarantee the quality of the finished fiber products. Furthermore, it also significantly restricts the intelligent construction of chemical fiber production. This work employs partially oriented yarn (POY) and full draw yarn (FDY) to develop an automatic knotting device. The catenary theory was used to confirm the state of the yarn and to determine the relevant parameters of the tension mechanism. The results showed that the developed automatic knotting device satisfactorily meets the conditions required for manual knotting. The curve equation that was calculated using the catenary conformations of the yarn state verified that the actual yarn state was consistent with the theory. Moreover, the work provides a theoretical foundation for subsequent mechanism optimizations.
Źródło:
Fibres & Textiles in Eastern Europe; 2022, 6 (151); 12--18
1230-3666
2300-7354
Pojawia się w:
Fibres & Textiles in Eastern Europe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fractional order PIλDμ controller with optimal parameters using Modified Grey Wolf Optimizer for AVR system
Autorzy:
Verma, Santosh Kumar
Devarapalli, Ramesh
Powiązania:
https://bibliotekanauki.pl/articles/2134890.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
integer order PID controller
fractional order PID controller
automatic voltage regulator
evolutionary optimization
Grey Wolf Optimizer
Opis:
In this paper, an automatic voltage regulator (AVR) embedded with fractional order PID (FOPID) is employed for the alternator terminal voltage control. A novel meta-heuristic technique, a modified version of grey wolf optimizer (mGWO) is proposed to design and optimize the FOPID AVR system. The parameters of FOPID, namely, proportional gain (ΚP), the integral gain ( ΚI), the derivative gain ( ΚD), λ and μ have been optimally tuned with the proposed mGWO technique using a novel fitness function. The initial values of the ΚP, ΚI , and ΚD of the FOPID controller are obtained using Ziegler-Nichols (ZN) method, whereas the initial values of λ and μ have been chosen as arbitrary values. The proposed algorithm offers more benefits such as easy implementation, fast convergence characteristics, and excellent computational ability for the optimization of functions with more than three variables. Additionally, the hasty tuning of FOPID controller parameters gives a high-quality result, and the proposed controller also improves the robustness of the system during uncertainties in the parameters. The quality of the simulated result of the proposed controller has been validatedby other state-of-the-art techniques in the literature.
Źródło:
Archives of Control Sciences; 2022, 32, 2; 429--450
1230-2384
Pojawia się w:
Archives of Control Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modeling and optimization of cutting parameters when turning EN-AW-1350 aluminum alloy
Autorzy:
Khrouf, F.
Tebassi, H.
Yallese, M. A.
Chaoui, K.
Haddad, A.
Powiązania:
https://bibliotekanauki.pl/articles/2174201.pdf
Data publikacji:
2022
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
sztuczna sieć neuronowa
optymalizacja
ANOVA
artificial neural networks
chip shape
optimization
response surface methodology
Opis:
An experimental investigation is carried out to examine the effects of various cutting parameters on the response criteria when turning EN-AW-1350 aluminum alloy under dry cutting conditions. The experiments related to the analysis of the influence of turning parameters on the surface roughness (Ra) and material removal rate (MRR) were carried out according to the Taguchi L27 orthogonal array (313) approach. The analysis of variance (ANOVA) was applied to characterizing the main elements affecting response parameters. Finally, the desirability function (DP) was applied for a bi-objective optimization of the machining parameters with the objective of achieving a better surface finish (Ra) and a higher productivity (MRR). The results showed that the cutting speed is the most dominant factor affecting Ra followed by the feed rate and the depth of cut. Moreover, the Artificial Neural Network (ANN) approach is found to be more reliable and accurate than its Response Surface methodology (RSM) counterpart in terms of predicting and detecting the non-linearity of the surface roughness and material removal rate mathematical models. ANN provided prediction models with a precision benefit of 8.21% more than those determined by RSM. The latter is easier to use, and provides more information than ANN in terms of the impacts and contributions of the model terms.
Źródło:
International Journal of Applied Mechanics and Engineering; 2022, 27, 2; 124--142
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multi-criteria optimization of the parameters of PSS3B system stabilizers operating in an extended power system with the use of a genetic algorithm
Autorzy:
Nocoń, Adrian
Paszek, Stefan
Pruski, Piotr
Powiązania:
https://bibliotekanauki.pl/articles/2134887.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
power system
power system stabilizers
polyoptimization
transient states
electromechanical swings
angular stability
Opis:
In the paper, the application of multi-criteria optimization of the parameters of PSS3B system stabilizers to damping electromechanical swings in an extended power system (PS) is presented. The calculations of the power system stabilizer (PSS) parameters were divided into two stages. In the first stage, single-machine systems, generating unit - infinite bus, of generating units critical for the angular stability of the PS were analyzed. Time constants and preliminary values of the PSS gains were calculated. In the second stage, the main one, the main gains on which the effectiveness of operation of PSSs depends the most were calculated by multi-criteria optimization of the extended PS. The calculations were carried out in several variants: for two-dimensional objective functions and the six-dimensional objective function. In multi-criteria optimization, the solution is not one set of PSS parameters, but a set of sets of these parameters, i.e. a set of compromises that were determined for each analyzed case. Additionally, for the six-dimensional compromise set, projections of this set on the planes connected with the quantities of individual generating units and the boundary of these projections on these planes were determined. A genetic algorithm adapted to multi-criteria issues was used to minimize the multivariate objective function. Sample calculations were made for the model of the National (Polish) Power System taking into account 57 selected generating units operating in high and extra high voltage networks (220 and 400 kV). The presented calculations show that the applied multi-criteria optimization of the PSS3B stabilizer parameters allows effectively damping electromechanical swings without worsening the voltage waveforms of generating units in the extended PS.
Źródło:
Archives of Control Sciences; 2022, 32, 2; 233--255
1230-2384
Pojawia się w:
Archives of Control Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł

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