MATHEMATICAL MODELING OF PROPELLER SERIES

2014 ◽  
Vol 156 (B2) ◽  
Author(s):  
M Bukarica
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Model ◽  
Expert System ◽  
Propulsion System ◽  
Test Results ◽  
Reliability Of Results ◽  
Mathematical Functions ◽  
Ship Propulsion ◽  
Mathematical Expressions ◽  
Selection Of

Propeller series are used in the process of designing the ship propulsion system, propeller and engine. The emergence of computers has made it possible to create a program, an expert system, which greatly accelerates and improves this process. In order to create such a program, it is necessary to provide a mathematical model of the test results, i.e. describe them by some mathematical expressions. In addition to this mathematical model, such a program must also have a mathematical model of the ship resistance. Precision and reliability of results produced by the expert system for the selection of the ship propulsion system depends on precision of the mathematical models it uses. Usual modeling procedures use standard mathematical functions and statistical methods. The aim of this paper is to present a "natural method" of mathematical modeling using spline functions, to compare them with each other, and to point out their advantages and deficiencies.

scholarly journals Mathematical modeling in economics for selection of optimum investment solution

2021 ◽  
Vol 273 ◽  
pp. 08003
Author(s):  
Arthur Alukhanyan ◽  
Olga Panfilova
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Model ◽  
Linear Programming ◽  
Mathematical Models ◽  
Programming Problem ◽  
Linear Programming Problem ◽  
Target Function ◽  
Investment Portfolio ◽  
Monetary Relations ◽  
Selection Of

This work is devoted to development of economic and mathematical models for selection of the optimum investment solution. Moreover, it states the basis for development of model examples and correction of the model considering the results obtained in the examples. In the work the problem is set for selection of the investment sources and objects, which is limited to the linear programming problem. The controlled variable and basic limitations simulating real credit and monetary relations are distinguished in the provided model. The discounted profit obtained from implementation of the optimum investment portfolio is considered as a target function. The economic and mathematical model presented in the article allows finding the optimum investment solution within the limits of the credit and monetary relations taking place both at the micro- and macroeconomic level.

Based on the Theory of the Miner Fatigue Damage of Fuzziness Analysis and Mathematical Modeling

2013 ◽  
Vol 437 ◽  
pp. 124-128 ◽  
Author(s):  
Xiao Fen Liu ◽  
Zhuo Wu ◽  
Ming Song ◽  
Min Zheng
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Model ◽  
Fatigue Life ◽  
Fatigue Damage ◽  
Membership Function ◽  
Test Results ◽  
Fuzzy Analysis ◽  
Loading Sequence ◽  
The Membership Function

In this paper, based on Miner rule, fuzzy analysis was carried out on predicting the fatigue damage, and mathematical model was established by considering loading sequence and interaction between loads and introducing the membership function. The analysis results show that the predicting fatigue life via the "Blurredregion" extension methods is closer to the test results.

scholarly journals Metode ARIMA untuk Memodelkan Volume Produksi Kelapa Sawit pada PT. SOCFINDO di Kabupaten Aceh Tamiang

2021 ◽  
Vol 3 (2) ◽  
pp. 309-319
Author(s):  
Wiwin Apriani ◽  
◽  
Rahmi Hayati
Keyword(s):  
Mathematical Model ◽  
Time Series ◽  
Stationary State ◽  
Oil Palm ◽  
Time Series Data ◽  
Series Data ◽  
Test Results ◽  
Selection Of

This study aims to create a mathematical model that can be used to predict the amount of oil palm that will be produced at PT. Socfindo in Aceh Tamiang Regency in the coming period. The data used is data on the amount of oil palm that is ready to be produced every month in 2012-2015. The method used is the ARIMA method. The selection of this method is based on the data used, namely time series data. Before carrying out further testing, first, ensure that the data used meets the stationary state. From the test results, it is found that the data used fulfills the stationary state, then it is found that the MA (1) model can be used to predict the time series data. Furthermore, we obtain a model that can be used to predict the volume of oil palm production at PT. Socfindo is: Z_t = a_t-0.4096a_ (t-1) +521.57 With a_t ~ N (0; 29192.72)

Integration of Expert System Into a CAD System of Springs

1987 ◽  
Author(s):  
Yu Jin ◽  
Liu Shihua ◽  
Qin Jing ◽  
Zhou Ji
Keyword(s):  
Mathematical Model ◽  
Expert System ◽  
Optimal Design ◽  
Structure Characteristic ◽  
Cad System ◽  
System Technique ◽  
Characteristic Features ◽  
Determination Of Parameters ◽  
Selection Of

Abstract By combining the reasoning design of the expert system with the analysis and calculation of spring based on a mathematical model and its optimal design, an intelligent spring CAD system has been established. The expert system technique is adopted for such non-calculating designing steps as the selection of scheme, the determination of parameters as well as for the development of the technological process, thus greatly strengthening the original CAD system of springs. This paper provides a detailed description of the function, structure, characteristic features and significance of the said system.

scholarly journals A method for selection of parameters of ship propulsion system fitted with compromise screw propeller

2007 ◽  
Vol 14 (4) ◽  
pp. 3-6 ◽  
Author(s):  
Jan Michalski
Keyword(s):  
Optimization Problems ◽  
Mathematical Optimization ◽  
Stage Structure ◽  
Propulsion System ◽  
Design Stage ◽  
Design Parameters ◽  
Inland Waterways ◽  
Ship Propulsion ◽  
Screw Propeller ◽  
Selection Of

A method for selection of parameters of ship propulsion system fitted with compromise screw propeller This paper concerns an algorithmic method for preliminary selection of parameters of ship propulsion system fitted with fixed screw propeller in the case when the ship's operation is associated with significant changes of waterway depth and width, hull resistance of the ship and its service speed. Mathematical model arguments of the considered design problem are main ship design parameters identified in the preliminary design stage. Structure of the formulated model complies with formal requirements for continuous- discrete mathematical optimization problems. The presented examples of application of the method concern an inland waterways ship fitted with compromise screw propeller optimized in the sense of minimization of fuel consumption for passing a given route distance within a given time. The elaborated method may be especially useful in designing such ships as: coasters, inland waterways ships, tugs, pushers, trawlers, mine sweepers, icebreakers etc.

scholarly journals Influence evaluation of the ship propulsion system on the energy efficiency for small, medium and large container vessels

2021 ◽  
Vol 327 ◽  
pp. 02005
Author(s):  
Viktor Nikiforov ◽  
Irina Kostova
Keyword(s):  
Energy Efficiency ◽  
Maximum Energy ◽  
Propulsion System ◽  
Fuel Type ◽  
Proper Selection ◽  
Ship Propulsion ◽  
Harmful Emissions ◽  
Large Container ◽  
Marine Vessels ◽  
Selection Of

The transportation of goods worldwide has a vital meaning for the entire of humanity. The seaborne transport is considered to be the most efficient – economically and environmentally friendly way to convey large amount of goods when compared to the other transport options available. Marine vessels contribute for the carriage of about 90 percent of the worldwide trade and a significant part of the goods delivered by sea are performed by container vessels. Even considered as the most efficient way of transportation the negative aspects of the shipping should not be neglected. The fuels intended for the ship propulsion generating enormous amounts of Greenhouse gases (GHG) and harmful emissions which are directly released into the atmosphere. When it comes to Energy Efficiency of the ships, the proper selection of the propulsion system and the fuel type used are essential with regard to achieve the best values. In the current paper a diverse alternative propulsion system options in order to achieve maximum Energy Efficiency on various sizes of container vessels will be analyzed.

scholarly journals Development of mathematical model prime cost milling operations optimization.

2014 ◽  
Vol 2014 (2) ◽  
pp. 86-91
Author(s):  
Андрей Аверченков ◽  
Andrey Averchenkov ◽  
Евгений Кукло ◽  
Evgeniy Kuklo
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Model ◽  
Cutting Tools ◽  
Prime Cost ◽  
Automatic Selection ◽  
Milling Operations ◽  
Software Modules ◽  
Operations Optimization ◽  
Selection Of

The automatic selection of cutting tools for efficient milling was issued. Mathematical modeling procedures and developing software modules for the automated selection of cutting tools were described.

Mathematical modeling of the frequencies of letters for their occurrence in corpora, words (types) and in the initial positions of words of corpora

Glottotheory ◽  
2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Hemlata Pande
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Model ◽  
American English ◽  
The Mathematical Model ◽  
Selection Of ◽  
National Corpus

AbstractIn the present paper an attempt has been made to determine the mathematical model for the frequencies of occurrence of letters in the corpora, in the word types of the corpora and in the initial positions of words of the corpora while both the word tokens and word types have been taken into account. In the current study corpora written in American English have been used by the selection of the entities from ‘The Open American National Corpus (OANC)’.

scholarly journals Mathematical Modeling of the Coaxial Quadrotor Dynamics for Its Attitude and Altitude Control

Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1232
Author(s):  
Wojciech Giernacki ◽  
Jarosław Gośliński ◽  
Jagoda Goślińska ◽  
Tadeo Espinoza-Fraire ◽  
Jinjun Rao
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Model ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Viscous Friction ◽  
Control Techniques ◽  
Aerial Vehicle ◽  
Altitude Control ◽  
Selection Of ◽  
Three Dimensional Space

In this paper, an easily implementable coaxial quadrotor model and its validation on data from a real unmanned aerial vehicle (UAV), are presented. The proposed mathematical model consists of two parts: description of orientation and position of the UAV in the three-dimensional space. It takes into consideration the gyroscopic effect, influence of the Coriolis force, viscous friction and a several drag-like effects (blade flapping, rotor drag, translational drag and profile drag). In contrast to multirotor models available in the literature, this one is characterized by complementarity in relation to the available control techniques. Depending on selection of these techniques, the model can be narrowed (simplified) to meet the needs without the loss of behaviour adequacy to a real UAV.

APPLICATION OF OPTIMIZATION OF SPECIFIED PARAMETERS OF THE ACCIDENT-RESISTANT FUEL SYSTEM OF THE HELICOPTER IN SIMINTECH SOFTWARE PACKAGE

2020 ◽  
pp. 7-13
Author(s):  
D. I. Smagin ◽  
K. S. Napreenko ◽  
R. S. Savel’ev ◽  
S. V. Grachev
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Model ◽  
Life Cycle ◽  
Software Package ◽  
Operation Mode ◽  
Design Stage ◽  
Fuel System ◽  
Software Complex ◽  
High Degree ◽  
Selection Of

The process of creating an accident-resistant fuel system (AFS) of a helicopter using mathematical modeling is considered. Possibility of applying optimization algorithms in mathematical modeling of parameters of units of accident-resistant fuel system of helicopter in domestic software complex SimInTech is studied. An approach to solving the problem of optimizing given parameters, both in theory and in practice, is described. Results of the simplest optimization of AFS parameters for nominal operation mode are covered, examples of algorithms for selection of unit parameters are shown. This method of researching the system will allow, with a high degree of accuracy, to determine the necessary parameters at the design stage of the system. It is worth noting that the functionality of the developed dynamic mathematical model in the SimInTech software package is sufficient to perform tasks not only of the conceptual design stage, but also of the subsequent stages of the AFS life cycle.

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