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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
321

Strypų konstrukcijų prisitaikomumo analizė inkrementiniu-iteratyviniu metodu / An incremental-iterative method for shakedown analysis of bar structures

Blaževičius, Gediminas 17 June 2011 (has links)
Darbo tikslas – tampriųjų-plastinių strypų konstrukcijų (santvaros, rėmų), veikiamų kartotinės kintamosios apkrovos, prisitaikomumo proceso ir būvio įtempių ir deformacijų analizė optimalaus konstrukcijų projektavimo kontekste. Darbo aktualumas grindžiamas prisitaikančių konstrukcijų optimizavimo uždaviniuose figūruojančių standumo sąlygų-apribojimų kokybės gerinimo būtinumu. Prisitaikančių konstrukcijų deformacijų būvis priklauso nuo apkrovimo istorijos, o poslinkių ribojimui taikoma nepakankamai tiksli Koiterio sąlyga arba liekamųjų poslinkių influentinė matrica, nepagrįstai laikant, kad plastinio deformavimo procesas yra išimtinai holonominis. Anotuojamame darbe apkrovimo istoriją siūloma įvertinti, atliekant papildomą inkrementinę deformacijų būvio analizę. Tyrimai atlikti taikant idealiai tamprių plastinių santvarų ir rėmų techniškosios skaičiavimo teorijos prielaidas (maži poslinkiai ir deformacijos). Taikomi ekstreminiai energiniai mechanikos principai, matematinio programavimo teorija ir metodai. Inkrementinės analizės matematiniai modeliai sudaryti, besikeičiančias plastines deformacijas tapatinant su distorsijomis. Taip nustatomos konkrečios apkrovimo istorijos liekamųjų poslinkių kitimo maksimalios ir minimalios reikšmės. Gautieji rezultatai panaudoti optimizavimo uždavinių sprendiniams tikslinti ir, esant būtinumui, leidžiantys keisti pradines pagrindinio optimizavimo uždavinio sąlygas. Pateikti išsamūs skaitinių eksperimentų rezultatai. / The purpose of this work is analysis of stress-deformation state of perfectly elastic-plastic shakedown structures (truss, frames) subjected to repeated variable load in the context of optimal design. Relevance of this work is based on a need of improvement of accurateness of stiffness constrains in optimization problems of structures. Stress-deformation state of shakedown structures depends on its loading history, while for the restriction of displacements inaccurate Koiter’s condition or an influence matrix of residual displacements, on the wrong supposition that the process of plastic deformation is exclusively holonomic, is used. In this work is proposed to evaluate loading history by performing an additional incremental analysis of stress-deformation state. This research was performed invoking the assumptions of technical computing theory of perfectly elastic-plastic trusses and frames (small deformations and displacements). Mechanics extremum energy principles, mathematical programming theory and methods are applied. Mathematical models of incremental analysis are composed by indentifying volatile plastic deformations with distortions. Thus particular maximum and minimum values of residual displacements are found. Obtained results are used to verify optimal design problems solutions and change the restrictions of main optimimization problem if necessary. Comprehensive results of numerical experiments presented.
322

Localização de modos de vibração em painéis modulados de lajes protendidas. / Mode localization of modular prestressed plate panels.

Kassab, Munir Mohamed 17 April 2009 (has links)
Nesta pesquisa, estuda-se o fenômeno de localização de modos de vibração em estruturas moduladas quase periódicas de comportamento linear e não-linear. Em particular, contempla-se uma aplicação na Engenharia Civil, os painéis de placas periódicos com pequenas imperfeições fracamente acoplados entre si através de viga de grande rigidez, e principalmente submetidos à variação de forças de membrana introduzidas por meio da protensão, o que só pode ser levado em conta introduzindo a rigidez geométrica no modelo matemático. No caso de sistemas lineares, a presença de pequenas desordens nas características de rigidez ou massa de subsistemas fracamente acoplados pode causar confinamento espacial nas vibrações livres, conhecido como Localização de Modos, e pode inibir a propagação da resposta forçada. È o que tem sido mostrado na literatura técnica, em especial nas áreas de Engenharia Mecânica e Aeroespacial. Os efeitos de localização serão obtidos numa perspectiva modal. O programa de elementos finitos DYMPLATE implementado pelo autor para análise dinâmica não-linear de estruturas de placas, será utilizado para modelar estruturas periódicas (ordenadas) e quase periódicas (desordenadas). Os modelos são linearizados em torno de configurações deformadas de referência. O problema algébrico de autovalores é resolvido para obter as freqüências naturais e correspondentes modos de vibração. Estruturas planas constituídas por placas protendidas com módulos repetidos, pequenas imperfeições e diferentes condições de apoio e de carregamento, serão utilizadas na investigação numérica da influência de diversos fatores na Localização de Modos, em especial as forças de membrana. / In this research, the phenomenon of vibration modes localization in nearly periodic modular structures of linear and nonlinear behavior is studied. Of special interest is an application in Civil Engineering, lightly coupled periodic plate panels with small imperfections, mainly submitted to the variation of membrane forces introduced by prestress forces, which can be only considered by introducing geometric stiffness in the mathematical model. In the linear case, the presence of small disorders in the stiffness or mass characteristics of lightly coupled sub-systems can cause spatial confinement of free vibrations, known as Mode Localization, and can inhibit the propagation of the forced response. That is what has been shown in the literature, especially in the areas of Mechanical and Aerospace Engineering. The effects of localization are viewed from a modal perspective. DYMPLATE, a finite element software implemented by the author for nonlinear dynamic analysis of plates, will be utilized to model ordered and disordered plate periodic structures. The models are linearized about a deformed reference configuration. The algebraic eigenvalue problem is solved to obtain the natural frequencies and corresponding modes shapes. Plane structures constituted by prestressed plates with repetitive dynamic characteristics, small imperfections and different boundary conditions and loads, will be utilized in the numerical investigation of the influence of numerous factors in the Mode Localization.
323

Estimação de modelos geoestatísticos com dados funcionais usando ondaletas / Estimation of Geostatistical Models with Functional Data using Wavelets

Sassi, Gilberto Pereira 03 March 2016 (has links)
Com o recente avanço do poder computacional, a amostragem de curvas indexadas espacialmente tem crescido principalmente em dados ecológicos, atmosféricos e ambientais, o que conduziu a adaptação de métodos geoestatísticos para o contexto de Análise de Dados Funcionais. O objetivo deste trabalho é estudar métodos de krigagem para Dados Funcionais, adaptando os métodos de interpolação espacial em Geoestatística. Mais precisamente, em um conjunto de dados funcionais pontualmente fracamente estacionário e isotrópico, desejamos estimar uma curva em um ponto não monitorado no espaço buscando estimadores não viciados com erro quadrático médio mínimo. Apresentamos três abordagens para aproximar uma curva em sítio não monitorado, demonstramos resultados que simplificam o problema de otimização postulado pela busca de estimadores ótimos não viciados, implementamos os modelos em MATLAB usando ondaletas, que é mais adequada para captar comportamentos localizados, e comparamos os três modelos através de estudos de simulação. Ilustramos os métodos através de dois conjuntos de dados reais: um conjunto de dados de temperatura média diária das províncias marítimas do Canadá (New Brunswick, Nova Scotia e Prince Edward Island) coletados em 82 estações no ano 2000 e um conjunto de dados da CETESB (Companhia Ambiental do Estado de São Paulo) referentes ao índice de qualidade de ar MP10 em 22 estações meteorológicas na região metropolitana da cidade de São Paulo coletados no ano de 2014. / The advance of the computational power in last decades has been generating a considerable increase in datasets of spatially indexed curves, mainly in ecological, atmospheric and environmental data, what have leaded to adjustments of geostatistcs for the context of Functional Data Analysis. The goal of this work is to adapt the kriging methods from geostatistcs analysis to the framework of Functional Data Analysis. More precisely, we shall interpolate a curve in an unvisited spot searching for an unbiased estimator with minimum mean square error for a pointwise weakly stationary and isotropic functional dataset. We introduce three different approaches to estimate a curve in an unvisited spot, we demonstrate some results simplifying the optimization problem postulated by the optimality from these estimators, we implement the three models in MATLAB using wavelets and we compare them by simulation. We illustrate the ideas using two dataset: a real climatic dataset from Canadian maritime provinces (New Brunswick, Nova Scotia and Prince Edward Island) sampled at year 2000 in 82 weather station consisting of daily mean temperature and data from CETESB (environmental agency from the state of São Paulo, Brazil) sampled at 22 weather station in the metropolitan region of São Paulo city at year 2014 consisting of the air quality index PM10.
324

Anslutning av givare och ett dSPACE-system till en hydraulisk kran

Josefsson, Per January 2009 (has links)
Det här rapporten är en del av mitt examensarbete för högskoleingenjörsexamen i elektroteknik vid Växjö Universitet, MSI. Arbetet är en del av ett större projekt kallat Kranstyrningsprojektet som bedrivs av Växjö Universitet, Rottne Industri med flera, vars syfte är att underlätta för förare att kontrollera den kran som finns på Rottnes skotare. För projektet har det använts en laborationskran och nu har önskemålet varit att det till kranen ska installeras ett nytt styrsystem från dSPACE. Dessutom vill man att nya givare ska sättas på kranen och kopplas till dSPACE. Man vill även ha en manual för att nya studenter ska kunna använda systemet. Det nya dSPACE-systemet består av en datorlåda med processor- och I/O-kort. Man kommunicerar med dSPACE från en PC. Arbetet med installationen har stött på flera problem och arbetet har dragit ut på tiden. När systemet till slut gick att använda utfördes ett par tester och sen implementerades det på kranen. Arbete med att ta fram underlag för installation av accelerometrar på kranen pågick samtidigt och en jämförelse mellan olika alternativ gjordes. Arbetet resulterade i att laborationskranen nu går att styra med det nyinköpta systemet från dSPACE och en manual skapades för att underlätta användandet av systemet. / This document is a part of my bachelor degree thesis in electronic engineering was done at Växjö University, MSI. This work is a part of a bigger project called Crane Tip Control which is pursued by Växjö University, Rottne Industri and others, whose purpose is to facilitate for drivers to control the crane used on forwarders from Rottne. For this project, a laboratory crane has been used and they requested that a new control system from dSPACE was installed to the crane. Also they want new sensors to be placed on the crane and connected to dSPACE. A manual should also be created for new students who want to use the system. The new dSPACE-system consists of a computer box with processor- and I/O-boards. Communication with dSPACE is done via a PC. The work with the installation has encountered many problems and the work has been overrun. When the system finally was working, some tests were performed and then the system was installed at the crane. A task to assemble data for installation of accelerometers, was done during the same time and a comparison between different alternatives was made. The work resulted in the laboratory crane is now able to be controled by the new dSPACE-system and a manual was created to facilitate the usage of the system.
325

Calculating zeros of analytic functions with MatLab

Henrysson, Magdalena January 2008 (has links)
Betrakta en analytisk funktion f som beror av en komplex variabel z och ett ändligt antal reella parametrar param1, param2, ..., paramk, där k är ett positivt heltal. Rötterna till funktionen, med avseende på variabeln z, erhålls genom att lösa ekvationen f(z, param1, param2, ..., paramk)=0. Således kommer dessa rötter att vara beroende av parametrarna. Låt en av parametrarna paramj, där j är ett positivt heltal mindre än eller lika med k, vara monotont ökande eller avtagande på ett reellt intervall. Även funktionens rötter kommer att variera, till följd av de olika värdena på parametern paramj. Ett datorprogram, som beräknar och undersöker rörelsen hos rötterna till en funktion då en parameter varierar, har utvecklats och implementerats i MatLab. Underprogram som använder numerisk analys i form av sekantmetoden för att beräkna approximationer av rötter och linear algebra för att kunna identifiera de rötter som är felaktiga, har också skrivits. Det vill säga, programmets huvudsakliga åtgärder ligger i att kontrollera om de beräknade värdena är korrekta och att rätta till de som är felaktiga. Examensuppgiften och det implementerade programmet har främst varit inriktade på ljuddämpare, vilket innebär en problemställning, där rötterna till en funktion undersöks för att analysera hur akustiska vågor fortplantas vid olika villkor. Således har den huvudsakliga målsättningen varit att förenkla tillvägagångssättet för att beräkna rötter. / Consider an analytic function f of a complex variable z and of a finite number of real parameters param1, param1, ..., paramk, for a positive integer k. The roots of the function, with respect to the variable z, are obtained by solving the equation f(z, param1, param2, ..., paramk)=0. Consequently those roots will depend on the parameters. Let one of the parameters paramj, where j is a positive integer less or equal to k, be monotonically increasing or decreasing on an interval of the real line. As a consequence of those different values of paramj, also the roots of the function f will vary. A computer program that calculates and examines the behavior of the roots of a function as one parameter varies, has been developed and implemented in MatLab. Subroutines have been written, which use numerical analysis by using the secant method to calculate approximations of roots and linear algebra to identify the false roots. That is, the main measures of this program is to make sure that the calculated values are correct and to adjust the false ones. The paper and the implemented program are principally concentrated on silencers, that is, on modal analysis. Modal analysis is the examination of how the shape and the behaviour of acoustic waves are affected by different conditions, which is done by studying the roots of a function. Consequently, the main purpose has been to facilitate the procedure of finding roots.
326

Calculating zeros of analytic functions with MatLab

Henrysson, Magdalena January 2008 (has links)
<p>Betrakta en analytisk funktion f som beror av en komplex variabel z och ett ändligt antal reella parametrar param1, param2, ..., paramk, där k är ett positivt heltal. Rötterna till funktionen, med avseende på variabeln z, erhålls genom att lösa ekvationen f(z, param1, param2, ..., paramk)=0. Således kommer dessa rötter att vara beroende av parametrarna. Låt en av parametrarna paramj, där j är ett positivt heltal mindre än eller lika med k, vara monotont ökande eller avtagande på ett reellt intervall. Även funktionens rötter kommer att variera, till följd av de olika värdena på parametern paramj.</p><p>Ett datorprogram, som beräknar och undersöker rörelsen hos rötterna till en funktion då en parameter varierar, har utvecklats och implementerats i MatLab. Underprogram som använder numerisk analys i form av sekantmetoden för att beräkna approximationer av rötter och linear algebra för att kunna identifiera de rötter som är felaktiga, har också skrivits. Det vill säga, programmets huvudsakliga åtgärder ligger i att kontrollera om de beräknade värdena är korrekta och att rätta till de som är felaktiga.</p><p>Examensuppgiften och det implementerade programmet har främst varit inriktade på ljuddämpare, vilket innebär en problemställning, där rötterna till en funktion undersöks för att analysera hur akustiska vågor fortplantas vid olika villkor. Således har den huvudsakliga målsättningen varit att förenkla tillvägagångssättet för att beräkna rötter.</p> / <p>Consider an analytic function f of a complex variable z and of a finite number of real parameters param1, param1, ..., paramk, for a positive integer k. The roots of the function, with respect to the variable z, are obtained by solving the equation f(z, param1, param2, ..., paramk)=0. Consequently those roots will depend on the parameters. Let one of the parameters paramj, where j is a positive integer less or equal to k, be monotonically increasing or decreasing on an interval of the real line. As a consequence of those different values of paramj, also the roots of the function f will vary.</p><p>A computer program that calculates and examines the behavior of the roots of a function as one parameter varies, has been developed and implemented in MatLab. Subroutines have been written, which use numerical analysis by using the secant method to calculate approximations of roots and linear algebra to identify the false roots. That is, the main measures of this program is to make sure that the calculated values are correct and to adjust the false ones.</p><p>The paper and the implemented program are principally concentrated on silencers, that is, on modal analysis. Modal analysis is the examination of how the shape and the behaviour of acoustic waves are affected by different conditions, which is done by studying the roots of a function. Consequently, the main purpose has been to facilitate the procedure of finding roots.</p>
327

Anslutning av givare och ett dSPACE-system till en hydraulisk kran

Josefsson, Per January 2009 (has links)
<p>Det här rapporten är en del av mitt examensarbete för högskoleingenjörsexamen i elektroteknik vid Växjö Universitet, MSI. Arbetet är en del av ett större projekt kallat Kranstyrningsprojektet som bedrivs av Växjö Universitet, Rottne Industri med flera, vars syfte är att underlätta för förare att kontrollera den kran som finns på Rottnes skotare. För projektet har det använts en laborationskran och nu har önskemålet varit att det till kranen ska installeras ett nytt styrsystem från dSPACE. Dessutom vill man att nya givare ska sättas på kranen och kopplas till dSPACE. Man vill även ha en manual för att nya studenter ska kunna använda systemet. Det nya dSPACE-systemet består av en datorlåda med processor- och I/O-kort. Man kommunicerar med dSPACE från en PC. Arbetet med installationen har stött på flera problem och arbetet har dragit ut på tiden. När systemet till slut gick att använda utfördes ett par tester och sen implementerades det på kranen. Arbete med att ta fram underlag för installation av accelerometrar på kranen pågick samtidigt och en jämförelse mellan olika alternativ gjordes. Arbetet resulterade i att laborationskranen nu går att styra med det nyinköpta systemet från dSPACE och en manual skapades för att underlätta användandet av systemet.</p> / <p>This document is a part of my bachelor degree thesis in electronic engineering was done at Växjö University, MSI. This work is a part of a bigger project called Crane Tip Control which is pursued by Växjö University, Rottne Industri and others, whose purpose is to facilitate for drivers to control the crane used on forwarders from Rottne. For this project, a laboratory crane has been used and they requested that a new control system from dSPACE was installed to the crane. Also they want new sensors to be placed on the crane and connected to dSPACE. A manual should also be created for new students who want to use the system. The new dSPACE-system consists of a computer box with processor- and I/O-boards. Communication with dSPACE is done via a PC. The work with the installation has encountered many problems and the work has been overrun. When the system finally was working, some tests were performed and then the system was installed at the crane. A task to assemble data for installation of accelerometers, was done during the same time and a comparison between different alternatives was made. The work resulted in the laboratory crane is now able to be controled by the new dSPACE-system and a manual was created to facilitate the usage of the system.</p>
328

Radiolokatoriaus elektromagnetinio spinduliavimo vertinimas / Evaluation of Radar Electromagnetic Radiation

Saja, Šarūnas 21 June 2011 (has links)
Baigiamojo darbo tikslas – radiolokatoriaus elektromagnetinio spinduliavimo srauto tankio skaičiavimas bei analizė, remiantis Europos Sąjungos bei Lietuvos higienos normomis impulsiniams elektromagnetinės spinduliuotės šaltiniams. Skaičiavimo ypatybė ta, kad atsižvelgiama į reljefo įtaką srauto kitimui erdvėje. Tyrimui naudojama Matlab duomenų analizės programa suteikia galimybę gauti maksimalų tikslumą bei ištirti galimą antenos aukščio mažinimą, neviršijant higienos normoje nustatyto 10µW/cm2 vidutinio elektromagnetinio srauto tankio vertės 1,5 m aukštyje gyvenamojoje zonoje. Parašytas programos kodas leidžia analizuoti bet kokio reljefo įtaką pasirinkto radiolokatoriaus spinduliavimo parametrams. Rezultatuose pateikiami dvimačiai bei trimačiai grafikai kaip pagrindą naudojant Palangos oro uosto teritorijos išplanavimą, taip pat skaičiavimai menamam reljefui bei esant skirtingiems antenos aukščio parametrams. Magistriniame darbe nustatyta, kad tiriamo radiolokatoriaus darbo zona atitinka higienos normas net ir sumažinus anteną iki minimalaus aukščio. Aptariami spinduliavimo mažinimo būdai, alternatyvių sistemų galimybė. / The object of this thesis is evaluation and analysis of spatial radar electromagnetic radiation density with reference to EU and Lithuania Hygiene Norm for pulse electromagnetic wave emitters. Relief influence on spatial electromagnetic radiation density distribution is taken into account. Calculations and analysis are processed using Matlab data analysis program and allows to upscale the precision and manipulate antenna height to reach its minimum value without exceeding 10μW/cm2 radiation density for inhabited area at a height of 1,5m as directed by Hygiene Norm. Written Matlab script enables to analyze various relief influence on a range of radar performance. Results are produced in the form of two and three dimensional charts having Palanga airport area as a base for building layout as well as the results for artificial relief including variable height of antenna. Results brought the conclusion of analyzed radar to be well ahead of the Hygiene Norm even with the minimum antenna height. Possible methods of minimizing radiation are explained in conjunction with new alternative aircraft detection systems being introduced.
329

Estudo comparativo do desempenho de controladores robustos aplicados a um sistema de tanques acoplados.

Galdino, Jean Carlos da Silva 27 May 2011 (has links)
Made available in DSpace on 2014-12-17T14:08:47Z (GMT). No. of bitstreams: 1 JeanCSG_DISSERT.pdf: 2590836 bytes, checksum: a8999e4e7cb4dfe6cb037286ddf5336d (MD5) Previous issue date: 2011-05-27 / Currently the uncertain system has attracted much academic community from the standpoint of scientific research and also practical applications. A series of mathematical approaches emerge in order to troubleshoot the uncertainties of real physical systems. In this context, the work presented here focuses on the application of control theory in a nonlinear dynamical system with parametric variations in order and robustness. We used as the practical application of this work, a system of tanks Quanser associates, in a configuration, whose mathematical model is represented by a second order system with input and output (SISO). The control system is performed by PID controllers, designed by various techniques, aiming to achieve robust performance and stability when subjected to parameter variations. Other controllers are designed with the intention of comparing the performance and robust stability of such systems. The results are obtained and compared from simulations in Matlab-simulink. / Atualmente os sistemas que qpresentam incertezas t?m atra?do muito a comunidade acad?mica do ponto de vista da investiga??o cient?fica e tamb?m das aplica??es pr?ticas. Uma s?rie de abordagens matem?ticas surgem com o objetivo de resolver problemas relacionados ?s incertezas de sistemas f?sicos reais. Nesse contexto, o trabalho aqui apresentado tem como foco a aplica??o da teoria de controle em um sistema din?mico n?o linear e com varia??es param?tricas visando a robustez. Utilizamos, como aplica??o pr?tica deste trabalho, um sistema de tanques associados da Quanser, em uma configura??o cujo modelo matem?tico ? representado por um sistema de segunda ordem com uma entrada e uma sa?da (SISO). O controle do sistema ? realizado por controladores PIDs, projetados por diversas t?cnicas, objetivando alcan?ar o desempenho e estabilidade robusta, quando submetido a varia??es de par?metros. Outros controladores s?o projetados com esse mesmo intuito e os resultados obtidos s?o comparados a partir de simula??es realizadas no Matlabsimulink.
330

Localização de modos de vibração em painéis modulados de lajes protendidas. / Mode localization of modular prestressed plate panels.

Munir Mohamed Kassab 17 April 2009 (has links)
Nesta pesquisa, estuda-se o fenômeno de localização de modos de vibração em estruturas moduladas quase periódicas de comportamento linear e não-linear. Em particular, contempla-se uma aplicação na Engenharia Civil, os painéis de placas periódicos com pequenas imperfeições fracamente acoplados entre si através de viga de grande rigidez, e principalmente submetidos à variação de forças de membrana introduzidas por meio da protensão, o que só pode ser levado em conta introduzindo a rigidez geométrica no modelo matemático. No caso de sistemas lineares, a presença de pequenas desordens nas características de rigidez ou massa de subsistemas fracamente acoplados pode causar confinamento espacial nas vibrações livres, conhecido como Localização de Modos, e pode inibir a propagação da resposta forçada. È o que tem sido mostrado na literatura técnica, em especial nas áreas de Engenharia Mecânica e Aeroespacial. Os efeitos de localização serão obtidos numa perspectiva modal. O programa de elementos finitos DYMPLATE implementado pelo autor para análise dinâmica não-linear de estruturas de placas, será utilizado para modelar estruturas periódicas (ordenadas) e quase periódicas (desordenadas). Os modelos são linearizados em torno de configurações deformadas de referência. O problema algébrico de autovalores é resolvido para obter as freqüências naturais e correspondentes modos de vibração. Estruturas planas constituídas por placas protendidas com módulos repetidos, pequenas imperfeições e diferentes condições de apoio e de carregamento, serão utilizadas na investigação numérica da influência de diversos fatores na Localização de Modos, em especial as forças de membrana. / In this research, the phenomenon of vibration modes localization in nearly periodic modular structures of linear and nonlinear behavior is studied. Of special interest is an application in Civil Engineering, lightly coupled periodic plate panels with small imperfections, mainly submitted to the variation of membrane forces introduced by prestress forces, which can be only considered by introducing geometric stiffness in the mathematical model. In the linear case, the presence of small disorders in the stiffness or mass characteristics of lightly coupled sub-systems can cause spatial confinement of free vibrations, known as Mode Localization, and can inhibit the propagation of the forced response. That is what has been shown in the literature, especially in the areas of Mechanical and Aerospace Engineering. The effects of localization are viewed from a modal perspective. DYMPLATE, a finite element software implemented by the author for nonlinear dynamic analysis of plates, will be utilized to model ordered and disordered plate periodic structures. The models are linearized about a deformed reference configuration. The algebraic eigenvalue problem is solved to obtain the natural frequencies and corresponding modes shapes. Plane structures constituted by prestressed plates with repetitive dynamic characteristics, small imperfections and different boundary conditions and loads, will be utilized in the numerical investigation of the influence of numerous factors in the Mode Localization.

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