scholarly journals Multicriteria Optimization of a Dynamic System by Methods of the Theories of Similarity and Criteria Importance

Mathematics ◽  
2021 ◽  
Vol 9 (22) ◽  
pp. 2854
Author(s):  
Sergey Misyurin ◽  
German Kreynin ◽  
Andrey Nelyubin ◽  
Natalia Nosova

The problem of multicriteria optimization of a dynamic model is solved using the methods of the similarity theory and the criteria importance theory. The authors propose the original model of a positional system with two hydraulic actuators, synchronously moving a heavy object with a given accuracy. In order to reduce the number of optimizing parameters, the mathematical model of the system is presented in a dimensionless form. Three dimensionless optimization criteria that characterize the accuracy, size, and quality of the dynamic positioning process are considered. It is shown that the application of the criteria importance method significantly reduces the Pareto set (the set of the best solutions). This opens up the possibility of reducing many optimal solutions to one solution, which greatly facilitates the choice of parameters when designing a mechanical object.

2019 ◽  
Vol 53 (3) ◽  
pp. 807-827
Author(s):  
Ali Balma ◽  
Mehdi Mrad

This paper addresses the problem of allocating the terminal nodes to the hub nodes in a telecommunication network. Since the flow processing induces some undesirable delay, the objective is to minimize the total flow processed by the hubs. This study focuses on a real life network of the tunisian operator Tunisie Telecom whose operations managers are concerned by the quality of service. We provide three compact formulations that give optimal solutions for networks of large size. In particular, the last two are obtained by applying the Reformulation-Linearization Technique to a nonlinear formulation of the problem. The latter formulation derived within this approach is the most computationally effective, as pointed out by the computational experiments conducted on the real life network of Tunisie Telecom with 110 nodes and 5 hubs. Finally, we discuss and compare between the single allocation and double allocation configurations.


2018 ◽  
Vol 9 (4) ◽  
pp. 22-36
Author(s):  
Mohammed Mahseur ◽  
Abdelmadjid Boukra ◽  
Yassine Meraihi

Multicast routing is the problem of finding the spanning tree of a set of destinations whose roots are the source node and its leaves are the set of destination nodes by optimizing a set of quality of service parameters and satisfying a set of transmission constraints. This article proposes a new hybrid multicast algorithm called Hybrid Multi-objective Multicast Algorithm (HMMA) based on the Strength Pareto Evolutionary Algorithm (SPEA) to evaluate and classify the population in dominated solutions and non-dominated solutions. Dominated solutions are evolved by the Bat Algorithm, and non-dominated solutions are evolved by the Firefly Algorithm. Old and weak solutions are replaced by new random solutions by a process of mutation. The simulation results demonstrate that the proposed algorithm is able to find good Pareto optimal solutions compared to other algorithms.


2014 ◽  
Vol 707 ◽  
pp. 283-288
Author(s):  
Xiang Dong Wen ◽  
Zheng Zhou ◽  
Wen Yang Pan ◽  
Mei Shao

According to GB/T3286.1-2012(The determination of calcium oxide and magnesium oxide content in limestone and dolomite), the mathematical model of magnesium oxide content determination in limestone by atomic absorption spectrometry was established. The various uncertainty factors of different elements for a sample were discussed and compared in the testing process. The confidence interval for the measurement result was (0.74±0.03)%,k=2 in uncertainty evaluation .The results showed that the variability of working curve and accuracy of standard solution volume for working curve were main influence factors of uncertainty. It could effectively reduce the uncertainty from the perspective of the main factors,and improve the quality of analysis.


2014 ◽  
pp. 105-118 ◽  
Author(s):  
Jelena Stankovic ◽  
Vesna Jankovic-Milic ◽  
Marija Radosavljevic

One of the ways to determine the benefits of a particular municipality and indicate its readiness to cooperate with potential investors is to promote standards of effective and transparent local administration. This task can be realized through the certification of cities and municipalities with a favorable business environment. Certification is a process that, among other things, allows the assessment of quality of services and information that municipalities provide for investors and businessmen. It is a process aiming at improvement of business environment in Serbia through institutional reforms with the active participation and cooperation of industry, municipalities and citizens. One of the key questions is to determine the importance of the criteria relevant for evaluating the attractiveness of municipality in terms of potential investors. Analysis of criteria importance for certification of cities and municipalities with a favorable business environment, shown in this paper, aims to identify those who have played a key role in the efficiency of municipalities and cities in attracting foreign direct investment. This paper presents three alternative ways of determining the importance of the criteria. The results of this analysis should indicate to the authorities of cities and municipalities possible ways of improving their position at the list of those with a favorable business environment.


2015 ◽  
Vol 9 (1) ◽  
pp. 1025-1032
Author(s):  
Shi Pengtao ◽  
Li Yan ◽  
Yang Mingshun ◽  
Yao Zimeng

To furthermore optimize the machining parameters and improve the surface quality of the workpieces manufactured by single point incremental forming method, the formation mechanism of the sacle veins on the metal incremental froming workpieces was studied through experiment method. The influence principle of the spindle speed, the feed speed and the material of tip of tools on the length of scale veins was obtained through analyzing the experimental results and building the mathematical model among the length of scale veins were feed speed and spindle speed through measuring the roughness of surfaces and observing the appearance of the forming workpieces. The experimental results showed that, the spindle speed, the feed speed and the material of tool tips have a significant effect on the scale veins formation on the surface of forming workpieces. Therefore, an appropriate group of spindle speed and feed speed can reduce the effect of scale veins on the roughness of single point incremental forming workpieces and furthermore improve the surface quality of forming workpieces.


2012 ◽  
Vol 19 (Special) ◽  
pp. 57-65 ◽  
Author(s):  
Mirosław Tomera

ABSTRACT The dynamical positioning system is a complex control consisting of a number of components, including: filters, observers, controllers, and propeller allocation systems. The design and preliminary analysis of operational quality of system operation are usually done based on numerical simulations performed with the aid of the mathematical model of the ship. The article presents a concept of the dynamic positioning system applied to steering the training ship Blue Lady used for training captains in the ship handling research and training centre owned by the Foundation for Safety of Navigation and Environment Protection in Ilawa/Kamionka. The simulation tests performed in the numerical environment of Matlab/Simulink have proved the usability of the designed system for steering a ship at low speed.


Open Physics ◽  
2018 ◽  
Vol 16 (1) ◽  
pp. 57-62 ◽  
Author(s):  
Sebastian Różowicz

Abstract The paper presents the results of analytical and experimental studies concerning the influence of different kinds of fuel additives on the quality of the spark discharge for different configurations of the ignition system. The wear of the spark plug electrode and the value of spark discharge were determined for various impurities and configurations of the air-fuel mixture.


2021 ◽  
pp. 200-206
Author(s):  
I.N. Sedinin ◽  
V.F. Makarov

It is considered the complex of operations of the technological process for the heat treatment of steel 95X18-Sh, as a result of which the material of the samples increases the hardness to 59...61 HRC, and also improves the physical and mechanical properties. A full-scale full factorial experiment of face milling of samples was carried out using the method of mathematical planning. In the experiments, a high-precision machine and a carbide cutting tool were used. To calculate the values of the roughness function, the following are taken as independent variables: cutting speed, feed per tooth and depth of cut. In order to determine the coefficients of the linear equation, a central compositional orthogonal plan of the second order for three factors was used. A matrix of levels of variation of independent variable factors and a matrix of experiment planning were compiled. A regression analysis of the obtained experimental statistical data was carried out using the Microsoft Excel, Statistica and Wolfram Alpha programs. As a result of the calculations, a mathematical model of the roughness of the machined surface and optimal cutting conditions were determined.


2021 ◽  
pp. 68-72
Author(s):  
Il'ya A. Meshchikhin ◽  
Sergej S. Gavryushin

As part of the development of monitoring systems for the operation of technical objects, the problem of improving the quality of monitoring systems for the loaded state is considered. Based on the analysis of the mathematical model of the structure and its loading, a methodology for the selection of measuring instruments was developed. The urgency of the problem of calculating substantiation of the choice of key points of the structure is shown, at which it is possible to measure deformations for the subsequent restoration of the existing loads with maximum accuracy. An approach based on the envelope method for determining the rational composition of measuring instruments for restoring the loads acting on the structure is stated.


Author(s):  
Satya Swesty Widiyana ◽  
Rus Indiyanto

ABSTRACTThis study was taken from the problems in Heaven Store ranging from turnover does not reach the target, the different display products for each branch, and a just few reference customer visiting from problems in customer satisfaction. because the values of input and output obtained from each branch has a different values so demanding customers Heaven Store to correct weaknesses in the efficiency of customer service and satisfaction, then we tried to respond to the challenges of these improvements to the study "Analysis of Measurement Efficiency Services Methods Data envelopment analysis (DEA) In Heaven Store in West Surabaya "So in this study, researchers will assist the managementHeaven Store for measuring the level of efficiency that Heaven store along 5th branches can improve the quality of service by using data envelopment analysis (DEA), which is a methods that determine the level of efficiency similar organization where efficiency is not determined by the organization concerned. It is hoped this analysis will help the management to withdraw the customer so that the customer can buy the products that are sold in Heaven Store. After calculation of the mathematical model by referring to the calculation of the mathematical model DEA CRS, obtained the efficiency 0.8479688 on the fifth branch Heaven Store, then after an improvement in input and output according to the reference fixes the target model of DEA CRS, then the value of the relative efficiency DMU 5 can be increased from 0.8479688 (inefficient) to 1.000000 (efficient). Keywords: Data Envelopment Analysis, customer satisfaction, efficiency


Sign in / Sign up

Export Citation Format

Share Document