scholarly journals ANGULAR MOVEMENT PROGRAM CALCULATION PROCEDURE SPACECRAFT WHEN TAKING THE SURFACE OF THE EARTH IN AREA MODE

2019 ◽  
Vol 27 (4) ◽  
pp. 86-100
Author(s):  
Oleg Viktorovich Lutz ◽  
Galina Alexandrovna Borshchova ◽  
Evgeny Dmitrievich Yarmolchuk ◽  
Alexander Alekseevich Manoilenko
Keyword(s):  
Mathematical Model ◽  
Angular Motion ◽  
Field Of View ◽  
Method Of Calculation ◽  
Angular Movement ◽  
The Earth ◽  
Program Calculation ◽  
Large Width ◽  
Definition Of ◽  
The Mathematical Model

Currently increased interest in satellite images of the Earth's surface with high resolution terrain  (1 to 10 m). To obtain such images, you must use a long focus optical system (OS) having a limited field of view that does not allow the images of the large width. To increase the effectiveness of shooting in modern space systems (SS) Earth observation provides the opportunity after shooting a segment of the Earth's surface to redirect the OS to another area and spend it shooting. With sufficient speed shift OS it is possible to survey two or more adjacent parcels, which is almost equivalent to the corresponding increase in the width of the field of view of the removing apparatus. In this connection there is the task of restoring the OS, which is solved by the use of appropriate hardware and software control the angular movement of the removing apparatus. When creating the SS there is also the need to solve the following tasks: calculation of the program angular motion in a given length of the removable sections and a predetermined number of adjacent strips to be shot, with the purpose of definition of system requirements, spacecraft (SC) control and calculation under given characteristics of the system orientation of the SC possible number of the maximum length and remove adjacent portions of the surface of the Earth. To solve these tasks the mathematical model software of angular motion of the SC. Given the necessary initial data, mathematical model and method of calculation of kinematic parameters of a software angular motion of a SC in the mode of area highway shooting adjacent sections of the Earth's surface located at a predetermined distance from a trace route SC; examples and results of numerical calculations of the programmes angular motion by moving the instrument in remote sensing.

scholarly journals Possibilities of improving the TD88 atmospheric total density model

2010 ◽  
pp. 57-61
Author(s):  
S. Segan ◽  
D. Marceta
Keyword(s):  
Mathematical Model ◽  
Control Model ◽  
Density Model ◽  
Total Density ◽  
Polyharmonic Function ◽  
The Earth ◽  
The Mathematical Model

In this paper we have examined possibilities for preserving and improving the total density model of the Earth?s neutral thermosphere TD88 (Sehnal and Posp?silov? 1988) via modelling differences between TD88 and NRLMSISE-00 (Picone et al. 2002), which is used as a control model. It is shown that these residuals can be approximated with polyharmonic function. Starting from this we have developed the mathematical model of the residuals to identify their origin and possibilities to improve the TD88 model itself.

Mathematical model of the artificial muscle with two actuators

2020 ◽  
pp. 095440622094156
Author(s):  
Ljubinko B Kevac ◽  
Mirjana M Filipovic ◽  
Ana M Djuric
Keyword(s):  
Mathematical Model ◽  
Control Structure ◽  
Artificial Muscle ◽  
Parallel Robot ◽  
Simulation Results ◽  
Proportional Derivative Controller ◽  
Definition Of ◽  
The Mathematical Model ◽  
The Given ◽  
Very High

Characteristic construction of cable-suspended parallel robot of artificial muscle, which presents an artificial forearm, is analyzed and synthesized. Novel results were achieved and presented. Results presented in this paper were initially driven to recognize and mathematically define undefined geometric relations of the artificial forearm since it was found that they strongly affect the dynamic response of this system. It gets more complicated when one has more complex system, which uses more artificial muscle subsystems, since these subsystems couple and system becomes more unstable. Unmodeled or insufficiently modeled dynamics can strongly affect the system’s instability. Because of that, the construction of this system and its new mathematical model are defined and presented in this paper. Generally, it can be said that the analysis of geometry of selected mechanism is the first step and very important step to establish the structural stability of these systems. This system is driven with two actuators, which need to work in a coordinated fashion. The aim of this paper is to show the importance of the geometry of this solution, which then strongly affects the system’s kinematics and dynamics. To determine the complexity of this system, it was presumed that system has rigid cables. Idea is to show the importance of good defined geometry of the system, which gives good basis for the definition of mathematical model of the system. Novel program package AMCO, artificial muscle contribution, was defined for the validation of the mathematical model of the system and for choice of its parameters. Sensitivity of the system to certain parameters is very high and hence analysis of this system needs to be done with a lot of caution. Some parameters are very influential on the possible implementation of the given task of the system. Only after choosing the parameters and checking the system through certain simulation results, control structure can be defined. In this paper, proportional–derivative controller was chosen.

Nonlinear waves in compacting media

1986 ◽  
Vol 164 ◽  
pp. 429-448 ◽  
Author(s):  
Victor Barcilon ◽  
Frank M. Richter
Keyword(s):  
Mathematical Model ◽  
Solitary Waves ◽  
Nonlinear Waves ◽  
Nonlinear Interaction ◽  
Phase Speed ◽  
Governing Equations ◽  
One Dimensional ◽  
The Earth ◽  
Permanent Shape ◽  
The Mathematical Model

An investigation of the mathematical model of a compacting medium proposed by McKenzie (1984) for the purpose of understanding the migration and segregation of melts in the Earth is presented. The numerical observation that the governing equations admit solutions in the form of nonlinear one-dimensional waves of permanent shape is confirmed analytically. The properties of these solitary waves are presented, namely phase speed as a function of melt content, nonlinear interaction and conservation quantities. The information at hand suggests that these waves are not solitons.

scholarly journals Computer Modeling in the Application to Geothermal Engineering

2021 ◽  
Vol 2021 ◽  
pp. 1-23
Author(s):  
Karpenko Vasily Nikolaevich ◽  
Yuriy Starodub ◽  
Andrii Havrys
Keyword(s):  
Remote Sensing ◽  
Mathematical Model ◽  
Mathematical Models ◽  
Computer Modeling ◽  
Thermal Energy ◽  
Geothermal Energy ◽  
Heat Fluxes ◽  
The Earth ◽  
Earth’S Interior ◽  
The Mathematical Model

In the article, investigation is given of the developed mathematical models of nonequilibrium in time and distributed in space thermodynamic state of Earth’s matter from its center to its surface depending on the cases of the presence and absence of an internal source of thermal energy concentrated in the center of mass taking into account known geophysical data about the nucleus, mantle, lithosphere and atmosphere, and endogenous and exogenous heat fluxes. The objects of research are as follows: mathematical models of geothermal energy of the Earth, its internal source, and heat balance of endogenous and exogenous heat fluxes on the Earth’s surface. Research methods used are as follows: thermometry in deep wells, ground and remote sensing of heat fluxes of the Earth and the planets of the Solar System, mathematical modeling of heat exchange and thermoelastic processes from compression of Earth’s matter by gravitational field energy information and classical physical and mathematical methods, and computer modeling. The aim of research: in computer modeling to provide new mathematical models that determine the geophysical parameters of geothermal energy, which are aimed on solving problems of energy, environmental and economic security of society, using modern technical means of calculating ground and remote sensing data development of geothermal resources, and regulation of the heat balance of the ecosystem, namely: (i) study of the geological structure of the lithosphere to a depth of 10 km by remote sensing to determine the physical parameters of its layers more accurately than ground methods; (ii) development of projects of geothermal power plants on the basis of single isolated wells of a given depth with a capacity of up to 2 ÷ 3 mW of electricity on continents of the globe; (iii) real-time monitoring and forecasting of the temperature field of the atmosphere according to its physical and chemical composition. The novelty of the obtained research results: (i) developed the mathematical model of the physical process of origin and distribution in the bowels of the density of geothermal energy of the Earth from the surface to its center, which is the density of internal energy of an elementary geological object, and which increases when approaching the center of the planet; (ii) developed the mathematical model of the thermal energy source of infrared (IR) waves of the elementary geophysical object of the Earth’s interior depending on the depth of its occurrence, which allows to determine the stable generation of geothermal energy by rocks in a deep well for extraction and conversion into electricity and to study the geological structure and physical properties of the Earth’s interior; (iii) the mathematical model of heat exchange between the layers of the Earth’s subsoil with the thermal energy of infrared waves according to the laws of Fourier thermal conductivity and Stefan–Boltzmann heat transfer, which together with the geothermal energy source model allows to determine a thermal capacity of rocks in a deep well; (iv) developed the mathematical model of stable action of a source of thermal energy in the center of mass of the Earth, in the absence of which it is hard to explain the power of its endogenous infrared heat flux, parameters of geothermal energy distribution in the Earth, and the current thermodynamic state of the atmosphere, and the change in temperature of which depends on the thermophysical parameters of the physical-chemical composition of the atmosphere more than on changes in the thermal activity of the Sun; (v) determination of new numerical values: thermophysical parameters of the Earth’s interior; kinetic, potential and own gravitational energy of the Earth and own gravitational energy of the planets of the Solar System.

Measurement and Calculation of Heat Exchanger Performance Using Film Method

Volume 3 ◽  
2004 ◽  
Author(s):  
Che´rif Bougriou ◽  
Rachid Bessai¨h ◽  
Kerstin Eckert ◽  
Mahfoud Kadja
Keyword(s):  
Heat Transfer ◽  
Mathematical Model ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Computer Code ◽  
Method Of Calculation ◽  
Finned Tubes ◽  
The Mathematical Model ◽  
The Heat Transfer Coefficient ◽  
Film Method

In this paper, we present a method of calculation by partial or total condensation of the water vapor contained in the humid air, over the smooth or finned tubes-heat recupurators. This study presents an implantation of the film method in a computer code developed here. The mathematical model used is validated by our experimental approach, using tubes bundles in staggered and aligned arrangements. The heat transfer coefficient by convection around the fin is supposed too be constant. The computer code predicts the heat flux exchanged in a range of 20% and 5%, in wet and dry regime, respectively. The apparent heat transfer coefficient by condensation can exceed 10 times the value of the heat transfer coefficient. The mathematical model used is validated with the experimental data obtained in this study.

scholarly journals Machine Directional Register System Modeling for Shaft-Less Drive Gravure Printing Machines

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Shanhui Liu ◽  
Xuesong Mei ◽  
Jian Li ◽  
Li'e Ma
Keyword(s):  
Mathematical Model ◽  
System Modeling ◽  
System Model ◽  
Experimental Setup ◽  
Gravure Printing ◽  
Servo Motor ◽  
Definition Of ◽  
The Mathematical Model ◽  
Register Error ◽  
Control Accuracy

In the latest type of gravure printing machines referred to as the shaft-less drive system, each gravure printing roller is driven by an individual servo motor, and all motors are electrically synchronized. The register error is regulated by a speed difference between the adjacent printing rollers. In order to improve the control accuracy of register system, an accurate mathematical model of the register system should be investigated for the latest machines. Therefore, the mathematical model of the machine directional register (MDR) system is studied for the multicolor gravure printing machines in this paper. According to the definition of the MDR error, the model is derived, and then it is validated by the numerical simulation and experiments carried out in the experimental setup of the four-color gravure printing machines. The results show that the established MDR system model is accurate and reliable.

The Estimation of the Thermal Properties of Refractory Materials According to the Temperatures Acceleration Curve at the Blast Furnace Blowing-In

2015 ◽  
Vol 1095 ◽  
pp. 476-482 ◽  
Author(s):  
A.N. Dmitriev ◽  
Maxim O. Zolotykh ◽  
Yury A. Chesnokov ◽  
Oleg Yu. Ivanov ◽  
Galina Yu. Vitkina
Keyword(s):  
Thermal Conductivity ◽  
Mathematical Model ◽  
Blast Furnace ◽  
Thermal Properties ◽  
Thermal Conductivity Coefficient ◽  
Refractory Materials ◽  
Different Types ◽  
Definition Of ◽  
The Mathematical Model

In a laying of a hearth it is usually used to ten different types of the flameproof materials. The characteristics of materials declared by the manufacturer can differ from the actual. For creation of the mathematical model [1, 2] temperatures distributions in a laying of the concrete furnace it is necessary to know thermal conductivity of materials of the specific parties used at construction of the furnace. Definition of the thermal conductivity coefficient allows adapt mathematical model for specific conditions of use. The technique of determination of thermal properties of refractory materials on the temperatures acceleration curve at blowing-in of the blast furnace is described.

Earth Rotation in the Hipparcos Reference Frame

1997 ◽  
Vol 165 ◽  
pp. 115-122 ◽  
Author(s):  
J. Vondrák ◽  
C. Ron ◽  
I. Pešek
Keyword(s):  
Mathematical Model ◽  
Reference Frame ◽  
Rheological Parameters ◽  
Earth Orientation Parameters ◽  
The Earth ◽  
Celestial Pole ◽  
The Mathematical Model ◽  
Orientation Parameters ◽  
Celestial Reference Frame

AbstractNew determination of the Earth orientation parameters (EOP), based on optical astrometry observations since the beginning of the century, is now under preparation by the Working group established by Commission 19 of the IAU. The Hipparcos catalog is to define the celestial reference frame in which the new series of EOP are to be described. The novelties of the prepared solution are the higher resolution (5 days) and more parameters estimated from the solution (celestial pole offsets, rheological parameters of the Earth, certain instrumental constants). The mathematical model of the solution is described, and the results based on the observations made with 46 instruments at 29 observatories and a preliminary Hipparcos catalog are presented.

Improving the Performance of a Two Way Flow Control Valve, Using a 3D CFD Modeling

2014 ◽  
Author(s):  
Emma Frosina ◽  
Adolfo Senatore ◽  
Dario Buono ◽  
Michele Pavanetto ◽  
Micaela Olivetti ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Flow Control ◽  
Fluid Dynamic ◽  
Control Valve ◽  
Operating Conditions ◽  
Cfd Modeling ◽  
Flow Control Valve ◽  
Development Costs ◽  
Definition Of ◽  
The Mathematical Model

The paper introduces a methodology aimed to optimize the performance of hydraulic components; in particular the design of a new two way flow control valve studying the valve internal fluid-dynamic behavior will be introduced. The methodology is based on the definition of a CFD tridimensional fluid-dynamic model. In fact, the model can help engineers to develop the best geometry, to optimize the valve performance, reducing the prototyping requirement and finally the time-to-market and, consequently, the development costs. At first, the original spool internal geometry has been evaluated and studied to tune the mathematical model and to validate it comparing its results with the data obtained through an experimental campaign. Then, the same approach has been applied to investigate several different internal spool geometries to define the best one in all operating conditions. A limited number of solutions have been prototyped and tested to verify the mathematical model predictions, in order to find the best configuration whose performances are consistent with the assigned objective for the component.

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