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Articles 1 - 27 of 27

Full-Text Articles in Engineering

Identification Of Faults In Highways Using Approximation Methods And Algorithms, Khudayberdiyev Khakkulmirzayevich Mirzaakbar, Anvar Asatilloyevich Ravshanov Feb 2024

Identification Of Faults In Highways Using Approximation Methods And Algorithms, Khudayberdiyev Khakkulmirzayevich Mirzaakbar, Anvar Asatilloyevich Ravshanov

Chemical Technology, Control and Management

Many fast Fourier transforms are used to identify defective parts of uneven surfaces on roads and send information to relevant organizations on the road, using the " RAVON YO‘LLAR" application installed on a mobile device during car movement. We determine the uneven parts of the road. Smooth and well-maintained roads reduce the risk of vehicle collisions, skidding and other road-related incidents. Timely measures contribute to overall safety, comfort and economic efficiency.


Algorithms For Multi-Factory Polynomial Modeling Of Technological Processes, Farrukh Do'stmirzayevich Jo'rayev, Murodjon Ashurqulovich Ochilov Feb 2023

Algorithms For Multi-Factory Polynomial Modeling Of Technological Processes, Farrukh Do'stmirzayevich Jo'rayev, Murodjon Ashurqulovich Ochilov

Chemical Technology, Control and Management

The article reveals the meaning and essence of the modeling method in the study of complex technological processes based on the problematic aspects of building multifactorial relationships and the principles for their elimination. In the case of non-linearity of multifactorial connections of a complex system, the expediency of approximating such functions by polynomials is substantiated. The authors' ideas about the increasing importance of interpolation methods in practice against the background of the possibility of simplification based on the use of modern mathematical hardware and software for integration into the process of modeling and optimizing technological processes due to the complexity …


Mathematical Models Of New Magnetoelastic Sensor For Measure Of Power And Vibration Parameters, Javhar Sulton Ugli Fayzullayev Mar 2021

Mathematical Models Of New Magnetoelastic Sensor For Measure Of Power And Vibration Parameters, Javhar Sulton Ugli Fayzullayev

Chemical Technology, Control and Management

In the paper, the mathematical models of the new magnetoelastic sensor for measuring power and vibration parameters are developed taking into account the aggregation or scattering of the parameters of electromagnetic chains and the characteristics of the magnetization curve of the magnetic conductor material. The analysis of the generated mathematical models and graphs based on them showed that the magnetic chain in which the coils are assembled does not take into account the nonlinearity of the magnetization curve of the magnetic conductive material (electrotechnical steel), the result is 12 ÷ 15% of the experimental results. It varies by 6 ÷ …


Optimizing Power Consumption Of Freight Railroad Bearings Using Laboratory Experimental Data, Carlos E. Lopez Iii, Constantine Tarawneh, Arturo A. Fuentes, Harry Siegal Jul 2020

Optimizing Power Consumption Of Freight Railroad Bearings Using Laboratory Experimental Data, Carlos E. Lopez Iii, Constantine Tarawneh, Arturo A. Fuentes, Harry Siegal

Mechanical Engineering Faculty Publications and Presentations

Based on projected freight truck fuel efficiency, freight railroad and equipment suppliers need to identify, evaluate and implement technologies and/or operating practices to maintain traditional railroad economic competitiveness. The railway industry uses systems that record the total energy efficiency of a train but not energy efficiency or consumption by components. Lowering the energy consumption of certain train components will result in an increase in its overall energy efficiency, which will yield cost benefits for all the stakeholders. One component of interest is the railroad bearing whose power consumption varies depending on several factors that include railcar load, train speed, condition …


Optimization Of Modes Of Electr Power Systems By Genetic Algorothms, B.M. Pulatov Sep 2019

Optimization Of Modes Of Electr Power Systems By Genetic Algorothms, B.M. Pulatov

Technical science and innovation

In article discusses issues for solving optimization problems based on the use of genetic algorithms. To date, the genetic use algorithm for solving various problems. Which includes the shortest path search, approximation, data filtering and others. In particular, data is being examined regarding the use of a genetic algorithm to solve problems of optimizing the modes of electric power systems. Imagine an algorithm for developing the development of mathematical models, which includes developing the structure of the chromosome, creating a started population, creating a directing force for the population, etc. As well as the presentation, the selected structure should take …


Approximation Model Of A Typical Mechanical Object With Distributed Parameters, A.F. Verlan, M.V. Sagatov, D.K. Karimova, U.S. Fayzullaev Jun 2019

Approximation Model Of A Typical Mechanical Object With Distributed Parameters, A.F. Verlan, M.V. Sagatov, D.K. Karimova, U.S. Fayzullaev

Technical science and innovation

The article discusses the method of approximation transformations for the study of a typical mechanical object with distributed parameters. A mathematical description of an object with distributed parameters, which is given in the form of a partial differential equation, and their structural models are considered. An approximation model has been obtained with a number of unique properties that have proven useful in the construction of structural models of electromechanical systems.


Computational Methods For Bicubic L1 Splines, Priyesh Koyu Rai Jan 2019

Computational Methods For Bicubic L1 Splines, Priyesh Koyu Rai

Graduate Research Theses & Dissertations

The past two decades have seen the development of L1 splines for interpolation and approximation of geometric data. L1 splines have been shown to preserve shapes better than the conventional L2 splines, especially for data with abrupt changes in the magnitude of spacing. Efficient computation plays an important role in the practical application of L1 splines. This thesis creates new computational methods for constructing bicubic L1 interpolating splines and bicubic L1 spline fits. The bicubic splines in this study are piecewise bicubic polynomials defined on a rectangular grid generated by the tensor product of nodes. We developed a hybrid computational …


Analytic Description Of The Magnetic Permeability Of The Core Of Magnetoelastic Force Sensors Against Mechanical Voltage, S.F Amirov, K.K Jurayeva Jun 2018

Analytic Description Of The Magnetic Permeability Of The Core Of Magnetoelastic Force Sensors Against Mechanical Voltage, S.F Amirov, K.K Jurayeva

Chemical Technology, Control and Management

The articlegives an analytical expression of the dependence of the relative magnetic permeability of the ferromagnetic core of the mafnetoelastic force sensor on the applied mechanical stresses. It is shown that for magnetoelastic force transducers whose magnetic circuit operates on a linear portion of the main magnetization curve, the dependence of the relative magnetic permeability of the ferromagnetic core on the applied mechanical stresses applied to the sensors can be approximated as a linear function with a negative coefficient of proportionality.


Process Modeling Of Optimum Mixing Of Cyanic Solutions With Use Of Intellectual Systems Of Measurement On A Basis To A Fuzzy Logic, O.A Jumayev, A.A Akhmatov, G.B Makhmudov Apr 2018

Process Modeling Of Optimum Mixing Of Cyanic Solutions With Use Of Intellectual Systems Of Measurement On A Basis To A Fuzzy Logic, O.A Jumayev, A.A Akhmatov, G.B Makhmudov

Chemical Technology, Control and Management

Analyzes the principles of the development of microprocessor-based intelligent measurement and control systems that operate based on fuzzy logic rules. Using the possibilities of microprocessor intelligent systems, methods of automatic adjustment of the selected regulator are based on the dynamic model of the object, using the example of the process of optimal displacement of cyanide solutions.


Decision Support Models For A Few Critical Problems In Transportation System Design And Operations, Ran Zhang Apr 2017

Decision Support Models For A Few Critical Problems In Transportation System Design And Operations, Ran Zhang

USF Tampa Graduate Theses and Dissertations

Transportation system is one of the key functioning components of the modern society and plays an important role in the circulation of commodity and growth of economy. Transportation system is not only the major influencing factor of the efficiency of large-scale complex industrial logistics, but also closely related to everyone’s daily life. The goals of an ideal transportation system are focused on improving mobility, accessibility, safety, enhancing the coordination of different transportation modals and reducing the impact on the environment, all these activities require sophisticated design and plan that consider different factors, balance tradeoffs and maintaining efficiency. Hence, the design …


An Accurate Approximation Formula For Pricing European Options With Discrete Dividend Payments, Song-Ping Zhu, Xinjiang He Jan 2016

An Accurate Approximation Formula For Pricing European Options With Discrete Dividend Payments, Song-Ping Zhu, Xinjiang He

Faculty of Engineering and Information Sciences - Papers: Part A

In this article, two relevant problems related to pricing European options with discrete dividend under the classic Black-Scholes framework are considered. For the case when a discrete dividend payment is proportional to the underlying asset value, we discuss an interesting phenomenon observed; the option price is independent of the dividend payment date. This appears to be at odds with one's intuition that dividend amount, as well as the dividend date, should both affect the price of a European call or put option. We reveal the fundamental reasons, from both mathematical and financial viewpoints, why this occurs. When the amount of …


Fault Approximation Tool For Grid-Connected Inverter-Interfaced Distributed Generators, Joel Kennedy, Philip Ciufo, Ashish Agalgaonkar Apr 2015

Fault Approximation Tool For Grid-Connected Inverter-Interfaced Distributed Generators, Joel Kennedy, Philip Ciufo, Ashish Agalgaonkar

Dr Philip Ciufo

A novel fault approximation tool (FAT) is presented for use in distribution networks with a high penetration of inverter-interfaced distributed generation. The FAT does not rely on balanced operation nor an absolute reference point for voltage calculations, both of which are required for Newton-Raphson load flow calculations. Simulations show that the FAT provides an accurate representation of the transient and steady-state fault response for unbalanced faults when juxtaposed with a detailed small-signal model. The `sub-transient' response of the inverter-interfaced distributed generation is omitted to remove data considered extraneous from the perspective of distribution line protection analysis. The FAT is not …


Multi-View Twri Scene Reconstruction Using A Joint Bayesian Sparse Approximation Model, Van Ha Tang, Abdesselam Bouzerdoum, Son Lam Phung, Fok Hing Chi Tivive Jan 2015

Multi-View Twri Scene Reconstruction Using A Joint Bayesian Sparse Approximation Model, Van Ha Tang, Abdesselam Bouzerdoum, Son Lam Phung, Fok Hing Chi Tivive

Faculty of Engineering and Information Sciences - Papers: Part A

This paper addresses the problem of scene reconstruction in conjunction with wall-clutter mitigation for compressed multi-view through-the-wall radar imaging (TWRI). We consider the problem where the scene behindthe-wall is illuminated from different vantage points using a different set of frequencies at each antenna. First, a joint Bayesian sparse recovery model is employed to estimate the antenna signal coefficients simultaneously, by exploiting the sparsity and inter-signal correlations among antenna signals. Then, a subspace-projection technique is applied to suppress the signal coefficients related to the wall returns. Furthermore, a multi-task linear model is developed to relate the target coefficients to the image …


A Dft Study On An Alkali Atom Doped Decahedral Silver Nanocluster For Potential Application In Opto-Electronics And Catalysis Dec 2014

A Dft Study On An Alkali Atom Doped Decahedral Silver Nanocluster For Potential Application In Opto-Electronics And Catalysis

Faculty of Engineering University of Malaya

A systematic study of the structural, electronic and optical properties of the decahedral bimetallic Ag12X cluster is presented in the framework of density functional theory (DFT), where one atom of an alkali metal (X = Li, Na, K, Rb, Cs, Fr) is added, replacing a Ag atom in the decahedral Ag-13 cluster in core (c-doped), vertex (v-doped) and surface (s-doped) positions. Geometrical optimization of the clusters indicated that Li and Na doped clusters exhibited the highest stability. The binding energy (BE), vertical ionization potential (VIP), vertical electron affinity (VEA) and HOMO-LUMO gaps were calculated to compare the electronic stability and …


The Odijk Regime In Slits, Douglas R. Tree, Wesley F. Reinhart, Kevin D. Dorfman May 2014

The Odijk Regime In Slits, Douglas R. Tree, Wesley F. Reinhart, Kevin D. Dorfman

Faculty Publications

De Gennes’ blob theory has been remarkably successful at describing weakly confined polymers in both slits and channels, and comparable results surround Odijk’s theory of deflection segments for strongly confined wormlike polymers in nanochannels. However, given the success of Odijk’s theory in channels, it is remarkable that there is no comprehensive theory for the simple case of a wormlike polymer strongly confined between two parallel plates. We propose such a theory by drawing inspiration from the existing literature on ideal wormlike chains in slits and Daoud and de Gennes’ idea of mapping a slit-confined chain to a two-dimensional chain. We …


Fault Approximation Tool For Grid-Connected Inverter-Interfaced Distributed Generators, Joel Kennedy, Philip Ciufo, Ashish Agalgaonkar Jan 2014

Fault Approximation Tool For Grid-Connected Inverter-Interfaced Distributed Generators, Joel Kennedy, Philip Ciufo, Ashish Agalgaonkar

Faculty of Engineering and Information Sciences - Papers: Part A

A novel fault approximation tool (FAT) is presented for use in distribution networks with a high penetration of inverter-interfaced distributed generation. The FAT does not rely on balanced operation nor an absolute reference point for voltage calculations, both of which are required for Newton-Raphson load flow calculations. Simulations show that the FAT provides an accurate representation of the transient and steady-state fault response for unbalanced faults when juxtaposed with a detailed small-signal model. The `sub-transient' response of the inverter-interfaced distributed generation is omitted to remove data considered extraneous from the perspective of distribution line protection analysis. The FAT is not …


Background And Available Potential Energy In Numerical Simulations Of A Boussinesq Fluid, Shreyas S. Panse Jan 2013

Background And Available Potential Energy In Numerical Simulations Of A Boussinesq Fluid, Shreyas S. Panse

Masters Theses 1911 - February 2014

In flows with stable density stratification, a portion of the gravitational potential energy is available for conversion to kinetic energy. The remainder is not and is called “background potential energy”. The partition of potential energy is analogous to the classical division of energy due to motion into its kinetic and internal components. Computing background and available potential energies is important for understanding stratified flows. In many numerical simulations, though, the Boussinesq approximations to the Navier-Stokes equations are employed. These approximations are not consistent with conservation of energy. In this thesis we re-derive the governing equations for a buoyancy driven fluid …


Approximation Algorithm For Data Broadcasting In Duty Cycled Multi-Hop Wireless Networks, Dianbo Zhao, Kwan-Wu Chin Jan 2013

Approximation Algorithm For Data Broadcasting In Duty Cycled Multi-Hop Wireless Networks, Dianbo Zhao, Kwan-Wu Chin

Faculty of Engineering and Information Sciences - Papers: Part A

Broadcast is a fundamental operation in wireless networks. To this end, many past studies have studied the NP-hard, broadcast problem for always-on multi-hop networks. However, in wireless sensor networks, nodes are powered by batteries, meaning, they have finite energy. Consequently, nodes are required to have a low duty cycle, whereby they switch between active and sleep state periodically. This means that a transmission from a node may not reach all of its neighbors simultaneously. Consequently, any developed broadcast protocols must consider collisions and the wake-up times of neighboring nodes. Henceforth, this paper studies the minimum latency broadcast scheduling problem in …


Approximation Algorithms For Interference Aware Broadcast In Wireless Networks, Dianbo Zhao, Kwan-Wu Chin Jan 2013

Approximation Algorithms For Interference Aware Broadcast In Wireless Networks, Dianbo Zhao, Kwan-Wu Chin

Faculty of Engineering and Information Sciences - Papers: Part A

Broadcast is a fundamental operation in wireless networks and is well supported by the wireless channel. However, the interference resulting from a node's transmission pose a key challenge to the design of any broadcast algorithms/protocols. In particular, it is well known that a node's interference range is much larger than its transmission range and thus limits the number of transmitting and receiving nodes, which inevitably prolong broadcast. To this end, a number of past studies have designed broadcast algorithms that account for this interference range with the goal of deriving a broadcast schedule that minimizes latency. However, these works have …


A Soft-In Soft-Out Detection Approach Using Partial Gaussian Approximation, Qinghua Guo, Licai Fang, Defeng (David) Huang, Sven Nordholm Jan 2012

A Soft-In Soft-Out Detection Approach Using Partial Gaussian Approximation, Qinghua Guo, Licai Fang, Defeng (David) Huang, Sven Nordholm

Faculty of Engineering and Information Sciences - Papers: Part A

This paper concerns the implementation of the softin soft-out detector in an iterative detection system. A detection approach is proposed based on the properties of Gaussian functions. In this approach, for the computation of the APP (a posteriori probability) of a concerned symbol, the other symbols are distinguished based on their contributions to the APP of the concerned symbol, and the symbols with less contributions are treated as Gaussian variables to reduce the computational complexity. The exact APP detector and the well-known LMMSE (linear minimum mean square error) detector are two special cases of the proposed detector. Simulation results show …


A Logistic Approximation To The Cumulative Normal Distribution, Shannon R. Bowling, Mohammad T. Khasawneh, Sittichai Kaewkuekool, Byung R. Cho Jan 2009

A Logistic Approximation To The Cumulative Normal Distribution, Shannon R. Bowling, Mohammad T. Khasawneh, Sittichai Kaewkuekool, Byung R. Cho

Engineering Management & Systems Engineering Faculty Publications

This paper develops a logistic approximation to the cumulative normal distribution. Although the literature contains a vast collection of approximate functions for the normal distribution, they are very complicated, not very accurate, or valid for only a limited range. This paper proposes an enhanced approximate function. When comparing the proposed function to other approximations studied in the literature, it can be observed that the proposed logistic approximation has a simpler functional form and that it gives higher accuracy, with the maximum error of less than 0.00014 for the entire range. This is, to the best of the authors’ knowledge, the …


Reactive Oxygen Emission From Microwave Discharge Plasmas, S. Popovic, M. Rašković, S. P. Kuo, L. Vuskovic Jan 2007

Reactive Oxygen Emission From Microwave Discharge Plasmas, S. Popovic, M. Rašković, S. P. Kuo, L. Vuskovic

Physics Faculty Publications

Metastable oxygen atoms and molecules have received increased interest because of their function in surface modification, bio-decontamination and many other industrial applications, in addition to the role in the upper atmospheric layer chemistry. We review work on production and detection of metastable oxygen and we describe our experiments, including the development of techniques for measurement of metastable molecular oxygen. We show that either metastable oxygen molecules or metastable oxygen atoms can be produced in large quantities in electrical discharges, carefully tailored to promote the required kinetics. Although the two species may coexist, colder discharge regimes favor production of molecules, while …


Design Optimization Of Solid Rocket Motor Grains For Internal Ballistic Performance, Roger Hainline Jan 2006

Design Optimization Of Solid Rocket Motor Grains For Internal Ballistic Performance, Roger Hainline

Electronic Theses and Dissertations

The work presented in this thesis deals with the application of optimization tools to the design of solid rocket motor grains per internal ballistic requirements. Research concentrated on the development of an optimization strategy capable of efficiently and consistently optimizing virtually an unlimited range of radial burning solid rocket motor grain geometries. Optimization tools were applied to the design process of solid rocket motor grains through an optimization framework developed to interface optimization tools with the solid rocket motor design system. This was done within a programming architecture common to the grain design system, AML. This commonality in conjunction with …


Methods For Approximate Reasoning, Perry Groot, Pascal Hitzler, Ian Horrocks, Boris Motik, Jeff Z. Pan, Heiner Stuckenschmidt, Daniele Turi, Holger Wache Jan 2005

Methods For Approximate Reasoning, Perry Groot, Pascal Hitzler, Ian Horrocks, Boris Motik, Jeff Z. Pan, Heiner Stuckenschmidt, Daniele Turi, Holger Wache

Computer Science and Engineering Faculty Publications

This deliverable shows examples about approximating symbolic inference engines in a Semantic Web environment. Approaches of language weakening, knowledge compilation, and approximated deduction are presented. The last one is evaluated in practical applications with mixed results.


Fuzzy System Identification Based Upon A Novel Approach To Nonlinear Optimization, Raymond Scott Starsman Apr 2003

Fuzzy System Identification Based Upon A Novel Approach To Nonlinear Optimization, Raymond Scott Starsman

Electrical & Computer Engineering Theses & Dissertations

Fuzzy systems are often used to model the behavior of nonlinear dynamical systems in process control industries because the model is linguistic in nature, uses a natural-language rule set, and because they can be included in control laws that meet the design goals. However, because the rigorous study of fuzzy logic is relatively recent, there is a shortage of well-defined and understood mechanisms for the design of a fuzzy system. One of the greatest challenges in fuzzy modeling is to determine a suitable structure, parameters, and rules that minimize an appropriately chosen error between the fuzzy system, a mathematical model, …


Missile Longitudinal Autopilot Design Using A New Suboptimal Nonlinear Control Method, Ming Xin, S. N. Balakrishnan Jan 2003

Missile Longitudinal Autopilot Design Using A New Suboptimal Nonlinear Control Method, Ming Xin, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A missile longitudinal autopilot is designed using a new nonlinear control synthesis technique called the θ-D approximation. The particular θ-D methodology used is referred to as the θ-D H2 design. The technique can achieve suboptimal closed-form solutions to a class of nonlinear optimal control problems in the sense that it solves the Hamilton-Jacobi-Bellman equation approximately by adding perturbations to the cost function. An interesting feature of this method is that the expansion terms in the expression for suboptimal control are nothing but solutions to the state-dependent Riccati equations associated with this class of problems. The θ-D H2 design has the …


Navigation Satellite Selection Using Neural Networks, Daniel J. Simon, Hossny El-Sherief May 1995

Navigation Satellite Selection Using Neural Networks, Daniel J. Simon, Hossny El-Sherief

Electrical and Computer Engineering Faculty Publications

The application of neural networks to optimal satellite subset selection for navigation use is discussed. The methods presented in this paper are general enough to be applicable regardless of how many satellite signals are being processed by the receiver. The optimal satellite subset is chosen by minimizing a quantity known as Geometric Dilution of Precision (GDOP), which is given by the trace of the inverse of the measurement matrix. An artificial neural network learns the functional relationships between the entries of a measurement matrix and the eigenvalues of its inverse, and thus generates GDOP without inverting a matrix. Simulation results …