scholarly journals Roll Attitude Determination of Spin Projectile Based on GPS and Magnetoresistive Sensor

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Dandan Yuan ◽  
Wenjun Yi ◽  
Jun Guan
Keyword(s):  
Mathematical Model ◽  
Attitude Determination ◽  
Accurate Determination ◽  
Blind Spot ◽  
Gps Measurements ◽  
Guidance And Control ◽  
Magnetoresistive Sensor ◽  
Proposed Model ◽  
And Control

Improvement in attack accuracy of the spin projectiles is a very significant objective, which increases the overall combat efficiency of projectiles. The accurate determination of the projectile roll attitude is the recent objective of the efficient guidance and control. The roll measurement system for the spin projectile is commonly based on the magnetoresistive sensor. It is well known that the magnetoresistive sensor produces a sinusoidally oscillating signal whose frequency slowly decays with time, besides the possibility of blind spot. On the other hand, absolute sensors such as GPS have fixed errors even though the update rates are generally low. To earn the benefit while eliminating weaknesses from both types of sensors, a mathematical model using filtering technique can be designed to integrate the magnetoresistive sensor and GPS measurements. In this paper, a mathematical model is developed to integrate the magnetoresistive sensor and GPS measurements in order to get an accurate prediction of projectile roll attitude in a real flight time. The proposed model is verified using numerical simulations, which illustrated that the accuracy of the roll attitude measurement is improved.

scholarly journals A Mathematical Model for Locating the Medical and Emergency Centers considering the Failure Probability of Centers

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Alireza Mosayebi ◽  
Barat Mojaradi ◽  
Ali Bonyadi Naeini ◽  
Seyed Hamid Khodadad Hosseini
Keyword(s):  
Mathematical Model ◽  
Strategic Planning ◽  
Failure Probability ◽  
Health Sector ◽  
Chemical Production ◽  
Coverage Level ◽  
Performance Accuracy ◽  
Proposed Model ◽  
Reducing Costs ◽  
And Control

Enhancing the amount of industrial and chemical production is one of the most important effects of increasing rural people’s migration to cities, which leads to many abnormalities in the healthcare domain. In this regard, one of the most important tasks of health sector managers is designing and implementing some programs to monitor and control the level of community health, which is one of the health organizations’ strategic planning. On the other hand, the location of service centers is one of the most important problems in the area of strategic planning by any organization because selecting an appropriate site for constructing facilities can have a significant effect on reducing costs and increasing the coverage level. However, an appropriate site to construct the facilities must also have maximum reliability in addition to reducing costs and increasing the coverage level. This problem is important because many factors, such as natural disasters, result in failure of centers and influence the confidence level of system performance. Therefore, it is necessary to consider maximizing reliability in locating centers. For this purpose, an integer mathematical model is presented in this paper to select the optimum site for constructing the medical and emergency centers by considering the failure probability of each center. The research model’s objective function minimizes the system costs, including the costs of construction, patient transfer, and failure of medical and emergency centers. Finally, a numerical example is designed and reviewed by real-world problems to ensure the performance accuracy of the proposed model.

scholarly journals The Brandon mathematical model describing the effect of calcination and reduction parameters on specific surface area of ex-ADU UO₂ powders

2016 ◽  
Vol 6 (3) ◽  
pp. 54-59
Author(s):  
Trong Hung Nguyen ◽  
Ba Thuan Le
Keyword(s):  
Mathematical Model ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Uranyl Carbonate ◽  
Proposed Model ◽  
And Control ◽  
The Relationship ◽  
Fabrication Parameters ◽  
Good Agreement

The report “Brandon mathematical model describing the effect of calcination and reduction parameters on specific surface area of UO2 powders” [14] has built up a mathematical model describing the effect of the fabrication parameters on SSA (Specific Surface Area) of ex-AUC (Ammonium Uranyl Carbonate) UO2 powders. In the paper, the Brandon mathematical model that describe the relationship between the essential fabrication parameters [reduction temperature (TR), calcination temperature (TC), calcination time (tC) and reduction time (tR)] and SSA of the obtained ex-ADU (Ammonium Di-Uranate) UO2 powder product has established. The proposed model was tested with Wilcoxon’s rank sum test, showing a good agreement with the experimental parameters. The proposed model can be used to predict and control the SSA of ex-ADU UO2 powders

scholarly journals Mathematical modeling of the corpse cooling under conditions of varying ambient temperature

2021 ◽  
Vol 7 (1) ◽  
pp. 29-35
Author(s):  
German V. Nedugov
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Model ◽  
Ambient Temperature ◽  
Analytical Determination ◽  
Time Of Death ◽  
Main Condition ◽  
Proposed Model ◽  
Thermometric Determination ◽  
Early Postmortem

Background: The constancy of the ambient temperature is the main condition to correctly determine the time of death by thermometric method. However, in practice, this requirement is met only in cases of death in closed rooms. In this study, an exponential mathematical model was proposed for corpse cooling under any changes in ambient temperature. Aim: This study aimed to develop a mathematical model to determine the time of death based on the NewtonRichman cooling law in changing ambient temperature conditions. Materials and methods: Mathematical modeling of corpse cooling under changing ambient temperature is performed, focusing on problem solving of thermometric determination of the time of death. The axillary hollow was used as the diagnostic zone of the corpse, and the temperature of which at the time of death is taken is 36.6С. Results: A method of reverse reproduction of the cadaver temperature in conditions of changing ambient temperature has been developed. Results allow a relatively simple analytical determination of the time of death in the early postmortem period. Conclusions: The proposed method is advisable to be used in forensic medical practice to determine the time of death in early postmortem period. The developed mathematical model is implemented in the format of the application program Warm Bodies NRN. Use of tympanic and intraocular thermometry was recommended within the proposed model.

scholarly journals Error Analysis and Error Allocation for Turntable Systems Used in GyroWheel Calibration Tests

2017 ◽  
Vol 2017 ◽  
pp. 1-13 ◽  
Author(s):  
Yuyu Zhao ◽  
Hui Zhao ◽  
Xin Huo ◽  
Yu Yao
Keyword(s):  
Error Analysis ◽  
Theoretical Basis ◽  
Attitude Determination ◽  
Control Device ◽  
Orientation Error ◽  
Accuracy Requirement ◽  
Calibration Accuracy ◽  
And Control ◽  
The Relationship

Calibration tests are of great importance to ensure rate-sensing accuracy of GyroWheel, an innovative attitude determination and control device. In the process of calibration tests, turntable errors are inevitable, which hinder the calibration accuracy and rate-sensing capability. Hence, error analysis for GyroWheel calibration tests is conducted, and the relationship between the calibration accuracy and the orientation error is established based on analytical derivation and numerical simulations. Subsequently, an error model of the turntable system is derived using rigid body kinematics, by which the relationship between the orientation error and turntable errors is described. According to sensitivity analysis and manufacturing capability, an error allocation method is proposed to determine the accuracy requirement of the test turntable, and the effectiveness of the proposed method is verified by repeated simulation tests. Based on the presented analysis and proposed method in this paper, the effects of various turntable errors on the calibration accuracy can be obtained quantitatively, and a theoretical basis for the determination of the turntable accuracy is provided, which are of great significance to guide the calibration tests and improve the calibration accuracy of GyroWheel.

Using informative Multinomial-Dirichlet prior in a t-mixture with reversible jump estimation of nucleosome positions for genome-wide profiling

2015 ◽  
Vol 14 (6) ◽  
Author(s):  
Rawane Samb ◽  
Khader Khadraoui ◽  
Pascal Belleau ◽  
Astrid Deschênes ◽  
Lajmi Lakhal-Chaieb ◽  
...  
Keyword(s):  
Simulated Data ◽  
Reversible Jump ◽  
Control Of Gene Expression ◽  
Monte Carlo Simulation Technique ◽  
Genome Wide ◽  
Proposed Model ◽  
Heuristic Strategy ◽  
And Control ◽  
Physical Access

AbstractGenome-wide mapping of nucleosomes has revealed a great deal about the relationships between chromatin structure and control of gene expression. Recent next generation CHIP-chip and CHIP-Seq technologies have accelerated our understanding of basic principles of chromatin organization. These technologies have taught us that nucleosomes play a crucial role in gene regulation by allowing physical access to transcription factors. Recent methods and experimental advancements allow the determination of nucleosome positions for a given genome area. However, most of these methods estimate the number of nucleosomes either by an EM algorithm using a BIC criterion or an effective heuristic strategy. Here, we introduce a Bayesian method for identifying nucleosome positions. The proposed model is based on a Multinomial-Dirichlet classification and a hierarchical mixture distributions. The number and the positions of nucleosomes are estimated using a reversible jump Markov chain Monte Carlo simulation technique. We compare the performance of our method on simulated data and MNase-Seq data from Saccharomyces cerevisiae against PING and NOrMAL methods.

scholarly journals A New Mathematical Model for the Accurate Determination of Volatile Fatty Acids Concentration in Anaerobic Digesters

2020 ◽  
Vol 06 (02) ◽  
pp. 67-84
Author(s):  
Gaston Nsavyimana ◽  
Salvator Kaboneka ◽  
Casimir Harerimana ◽  
Chema Keffala ◽  
Marc Elskens ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Fatty Acids ◽  
Volatile Fatty Acids ◽  
Accurate Determination ◽  
Anaerobic Digesters

scholarly journals Mathematical Model for Velocity Calculation of Three Types of Vehicles in the Case of Pedestrian Crash

2018 ◽  
Vol 68 (3) ◽  
pp. 95-110
Author(s):  
Hoxha Gëzim ◽  
Shala Ahmet ◽  
Likaj Ramë ◽  
Bajrami Xhevahir
Keyword(s):  
Mathematical Model ◽  
Accurate Determination ◽  
Geometrical Parameters ◽  
Vehicle Speed ◽  
Model Formulation ◽  
Vehicle Velocity ◽  
Pedestrian Accidents ◽  
Throw Distance ◽  
Front Profile

AbstractThis paper treats influencing factors in the determination of vehicles speed on the pedestrian crash moment according to pedestrian throw distance and formulates a mathematical model for vehicle speed determination. Vehicle speed is one of the highest causes of accidents. The mathematical model formulation (as the target of this paper) for velocity calculation, in the case of pedestrian accidents, presents great help and guidance to experts of this field when dealing with accident analysis that through accurate determination of this parameter to find other circumstances as close as possible to the technical process of pedestrian accidents. The target of this paper is to define a mathematical model formulation for vehicle velocity calculation in pedestrian crash moment depending on relevant parameters. For the purpose of model formulating, we have selected three cases of real accidents that involved vehicles (“Peugeot 307”, “VW Golf ” and “Mercedes E 220”) with different geometrical parameters of the front profile and pedestrians with different heights and weights. For regression analysis we used “R” and “SPSS” software, which enables the statistical analysis of the data and mathematical model formulation. Also, for analysis of impact of relevant factors, model formulation and model testing have used “Virtual Crash” and “PC Crash” software, which enables pedestrian-vehicle crash simulation using vehicles with real technical characteristics and various pedestrian characteristics. Inductive, comparative, and deductive methods are part of the research methods in this paper.

scholarly journals Determinación Mejorada del Volumen de Pesas Patrón por Medición Geométrica

2019 ◽  
Vol 7 (20) ◽  
Author(s):  
Omar Jair Purata Sifuentes
Keyword(s):  
Mathematical Model ◽  
Current Model ◽  
Title Page ◽  
Manufacturing Processes ◽  
Volume Determination ◽  
New Model ◽  
Proposed Model ◽  
Surface Contact ◽  
Geometric Measurement

<div class="page" title="Page 1"><div class="layoutArea"><div class="column"><p><span><strong>Purpose</strong>  </span><span>̶  </span><span>to develop an improved mathematical model for volume determination of standardized weights by geometric measurement.</span></p><p><span><strong>Methodology</strong>  </span><span>̶  </span><span>the new model eliminates an assumption considered in the current model published in the OIML R 111-1 recommendation, since it considers existing deviations from the assumed shape of the weights in the current model, specifically in the so-called knob and ring sections. These deviations might originate during the manufacturing processes of the weights. </span></p><p><span><strong>Results</strong>  </span><span>̶  </span><span>an improved mathematical model for the calculation of the volume of standard weights by geometric measurement was deduced. Additionally, the model has the advantage of eliminating the risk of scratching the weights, which makes it possible to extend the use of the new model to higher accuracy classes.</span></p><p><span><strong>Limitations</strong>  </span><span>̶  </span><span>the proposed model involves the possibility of making geometric measurements without surface contact of the weights, for example, with an optical comparator. </span></p><p><span><strong>Findings</strong>  </span><span>̶  </span><span>an assessment of the current model against data previously published allows highlighting the relevance and higher accuracy of the new model, which makes it possible to calculate the density of standard weights, even for E class, through only geometric measurements. </span></p></div></div></div>

scholarly journals Numerical Analysis of Switching Processes in Class D Modulators

2021 ◽  
Vol 7 (1) ◽  
pp. 71-80
Author(s):  
V. Nikolaev ◽  
E. Rylov ◽  
D. Devyatkin ◽  
R. Nikolaev
Keyword(s):  
Mathematical Model ◽  
Optimal Control ◽  
Numerical Analysis ◽  
Output Voltage ◽  
Accurate Determination ◽  
Power Losses ◽  
Active Devices ◽  
Current Pulses ◽  
Class D

The article investigates the switching processes in class D modulators for optimal control of active devices (transistors, triodes, tetrodes, etc.) in real conditions, to reduce power losses in them and non-linear distortions of the modulator output voltage, as well as more accurate determination of the devices efficiency. The presented mathematical model takes into account the inertia of the switching processes, the duration of the rise and fall fronts of voltage and current pulses, as well as losses in switching elements.

Analysis, modeling and simulation of step up converter using Matlab–Simulink and simplorer

2016 ◽  
Vol 07 (02) ◽  
pp. 1650004
Author(s):  
Walid Emar
Keyword(s):  
Accurate Determination ◽  
Simulation Software ◽  
Control Technique ◽  
Output Current ◽  
Two Phase ◽  
Solar Systems ◽  
Development Costs ◽  
And Control ◽  
Operating Points

The basic configuration of step up converter usually used in photovoltaic solar systems to increase the DC voltage generated at their outputs suffers from some drawbacks just like high ripple in the output voltage, greater losses in the system and unstable dynamic behavior. To eliminate these drawbacks, this paper introduces a two-phase connection of step up converter with uncoupled smoothing reactors. Detailed analysis, simulation and control strategy have been proposed in this paper to investigate the advantages of using such connection with uncoupled reactors. This paper is intended to prove that two-phase connection with uncoupled reactors helps increasing the output power of the converter, minimizing its output ripple and making its control easier and more efficient. It also increases the converter chopping frequency and consequently decreases the size of smoothing reactors and filters used in the system. Concerning the design of such converters, it requires a long working period of time with a significant cost and specific technical tests at nominal operating points. Therefore, simulation can essentially decrease economic and development costs. Using modulation and simulation software techniques (Simplorer, Simulink, and Matlab) throughout this paper helped simulation of very fast the converter behavior and accurate determination of its dynamic characteristics. Moreover, the paper deals with modulation of voltage control technique using Matlab and Simplorer, thus regulating the converter output current and voltage. Simulation results show that this control technique provides robust output current and voltage of step up converters and is more feasible for their chopper up conversion technique.

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