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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.
41

A Study of Problem-Solving Strategies in Linear Equations with One Unknown for Junior High School Students under the Different Understanding of the Equal sign

Pan, Heng-tsu 23 June 2010 (has links)
The purpose of this study is to investigate students¡¦ understanding of the equal sign, problem-solving strategies of equations with one unknown, and the strategies of solving equations with one unknown under different understanding types of the equal sign. To achieve this purpose, the investigator did a survey and development instruments. The participants were 203 seventh-grade students in a convenient sample. Descriptive statistics were used to analyze data in frequency and percentages. The main results was that participants with a relational definition of the equal sign were the most (close to 50%), and an operational definition of the equal sign was approximately 1/4. There was a higher successful performance associated with a relational definition than an operational definition. The primary strategy of operations on the left-hand side of equal sign is the mathematical operations; the main strategy of an unknown quantity on the right-hand side of the equal sign was by going to the parenthesis-reverse and bringing different denominators into a common denominator; the principal strategies of one number on the right-hand side of the equal sign, equations with operations on the right side of the equal sign and equations with operations on both sides of the equal sign are cover-up and transposing. To use the strategies of trial and error substitution and undoing is minority in a linear equation with one unknown. The strategy of an operational definition participant in five equal sign topics is similar to the strategy of one with a relational definition. However, those with a relational definition apply multiple strategies and exhibited varying particular and algebraic property. On the other hand, participants with an operational definition used arithmetic strategies more frequently than participants with a relational definition. From the above results, the researcher suggested instruction to include strategies with algebraic property to help learners to develop stable understanding of the equal sign in Algebra. In addition, the recommendation is to have teachers to encourage students to apply multi-dimensional thinking and different strategies in algebraic problem-solving.
42

Generalized minimal polynomial over finite field and its application in coding theory

Jen, Tzu-Wei 27 July 2011 (has links)
In 2010, Prof. Chang and Prof. Lee applied Lagrange interpolation formula to decode a class of binary cyclic codes, but they did not provide an effective way to calculate the Lagrange interpolation formula. In this thesis, we use the least common multiple of polynomials to compute it effectively. Let E be an extension field of degree m over F = F_p and £] be a primitive nth root of unity in E. For a nonzero element r in E, the minimal polynomial of r over F is denoted by m_r(x). Then, let Min (r, F) denote the least common multiple of m_r£]^i(x) for i = 0, 1,..., n-1 and be called the generalized minimal polynomial of over F. For any binary quadratic residue code mentioned in this thesis, the set of all its correctable error patterns can be partitioned into root sets of some generalized minimal polynomials over F. Based on this idea, we can develop an effective method to calculate the Lagrange interpolation formula.
43

Modelling and Simulation of Unknown Factors in Simulation Based Acquisition

Hultberg, Ida January 2002 (has links)
<p>When a new product should be acquired, a model over its functionality is made. A quite new idea in the military area is to use simulations to find out what and how much to acquire. Since the product never has been on the market before it is hard to know how factors in the surroundings, like weather and other active objects, will affect it. Therefore these unknown factors that appear during the creation or acquiring of a new product need to be taken into consideration.</p><p>A literature study is performed about how modelling of simulations can be done, and how unknown factors can be considered when modelling a simulation. The study goes into if unknown factors are taken into consideration when modelling in the Process component in Simulation Based Acquisition (SBA). The result of this study shows that SBA facilitates in the process of finding and reducing unknown factors.</p>
44

Doubling and Desire

Zepf, Diana January 2010 (has links)
This thesis proposes that an investigation into the phenomenon of doubling may engage architecture with a type of desire that has deep rooted connections with the complexities of human nature, with the very human condition of desiring to know who/what/where/when/how we are. It proposes that an experience of doubling is suggestive of a specific kind of affective space that tests this relationship, expanding into the interval we have formed between our body, its being and space. The proposal is to explore the material, spatial, and psychological characteristics of such a phenomenon - to understand the virtual space created through this doubling and its architectonic characteristics. The design ambition of this thesis is to construct an architectural fiction that engages with this doubling. If architecture has the capacity to embody the ambitions and anxieties of society, the work produced attempts to invoke, through choreographed doublings manifested by the movement of figure and light through constructions in time, that human condition of desire that is concerned with finding/defining itself in the unknown, not to provide an answer for what the unknown is, but to engage with its enigmatic nature. By engaging in the protean dynamics of doubling and desire, this thesis attempts to poeticize the interval between the body and its built environment.
45

Bringing our boy home : the Tomb of the Unknown Warrior, its visitors, and contemporary war remembrance in New Zealand : a thesis submitted to the Victoria University of Wellington in partial fulfilment of the requirements for the degree of Master of Museum and Heritage Studies /

Phipps, Gareth. January 2009 (has links)
Thesis (M.M.H.S.)--Victoria University of Wellington, 2009. / Includes bibliographical references.
46

Integrated structural study of the FrpD protein from Neisseria meningitidis / Crystallographic study of the iron-regulated outer membrane lipoprotein (FrpD) from Neisseria meningitidis

SVIRIDOVA, Ekaterina January 2016 (has links)
Neisseria meningitidis (N. meningitidis) is a Gram-negative commensal bacterium colonizing nasopharynx of about 10 % of healthy individuals, which can cause invasive diseases, such sepsis and meningitis, upon occasional penetration into bloodstream. Pathogenesis of N. meningitidis appears to be directly related to conditions of limited iron availability. Under these conditions two proteins of unknown function: FrpC and FrpD, are synthesized. FrpD is a highly conserved lipoprotein of N. meningitidis anchored to the bacterial outer membrane. It is known that FrpD tightly binds the FrpC protein, which belongs to the Repeat-in-Toxin (RTX) protein family and may act as bacterial exotoxin. However, the mechanism of FrpD-FrpC interaction and the exact function of this complex are unknown due to the absence of structural information on these proteins. Therefore, we set out to determine the structure of FrpD and provide insights into its interaction mechanism with FrpC and structure-functional relationships of these two proteins. We determined the first crystal and solution structures of the FrpD protein. We found that atomic structures of FrpD reveal a novel protein fold. We uncovered the structure-function relationships underlying the mechanism of interaction between the FrpD and FrpC proteins and tested the putative function of the FrpD-FrpC1-414 complex in vitro. Finally, we proposed the putative function of the FrpD-FrpC1-414 complex as a new minor adhesin of N. meningitidis, which mediates the bacterial adhesion to the host epithelial cells and facilitate the colonization. Our work constitutes the first step in clarifying the molecular basis of the FrpD-FrpC interaction and sets the base for further investigation of the role of FrpD and FrpC in the virulence mechanism of N. meningitidis.
47

Identificação e análise da função de transferência do circuito equivalente de um sistema de medição por correntes parasitas

Tondo, Felipe Augusto January 2016 (has links)
Este trabalho apresenta o estudo de um sistema genérico de medição que utiliza o princípio das correntes de Foucault, comumente conhecidas como correntes parasitas. O modelo do sistema é representado como um circuito elétrico equivalente composto por R1 e L1, respectivamente caracterizando a resistência e a indutância do circuito primário, as quais são conhecidas por uma bobina de excitação. Já no secundário, R2 e L2, estão representando a perda ôhmica e a indutância da amostra no qual as correntes parasitas são induzidas, além de outros dois componentes, M indutância mútua dos indutores acoplados e k, coeficiente relacionado ao acoplamento magnético entre os circuitos primário e secundário. A análise tradicionalmente utilizada para este tipo de medição é a avaliação da reflexão da impedância equivalente do circuito secundário representando a amostra no circuito primário. O trabalho analisa as equações de malha do circuito equivalente no domínio da frequência e identifica os parâmetros do modelo. A partir da identificação do sistema realizada com os ensaios experimentais, foi possível descobrir a constante de tempo indutiva τL do sistema. A partir dessa constante, observou-se a variação acentuada da mesma em relação a variação da impedância equivalente. Ainda é apresentada uma estimativa dos valores de R2 e L2 realizada por meio da unificação das informações obtidas com a identificação, aliada com as informações de campo magnético obtidas a partir de um sensor do tipo GMR e pela simulação em um software de elementos finitos COMSOL Multiphysics. / This work presents the study of a generic measurement system that uses the prin- ciple of eddy currents. The system model is represented as an equivalent electric circuit composed of R1 and L1 respectively characterizing the resistance and induc- tance of primary circuit, which are known by an excitation coil. In the secondary, R2 and L2 are representing the ohmic loss and the inductance of the sample in which the eddy currents are induced, in addition two other components, the mutual induc- tance of the coupled inductors and k, coefficient related to the magnetic coupling between the primary and secondary circuits. The analysis traditionally used for this type of measurement is the reflection evaluation of the equivalent impedance of the secondary circuit representing the sample in the primary circuit. The work analyzes the mesh equations of the equivalent circuit in the frequency domain and identifies the parameters of the model. From the identification of the system performed with the experimental tests, it was possible to discover the inductive time constant τL of the system. From this constant, it was observed the sharp variation of the same in relation to the variation of equivalent impedance. An estimate values, R2 and L2 performed by unification of the information obtained with the identification, to- gether with the magnetic field information obtained from a GMR type sensor and by simulation in a finite element software COMSOL Multiphysics.
48

Identificação e análise da função de transferência do circuito equivalente de um sistema de medição por correntes parasitas

Tondo, Felipe Augusto January 2016 (has links)
Este trabalho apresenta o estudo de um sistema genérico de medição que utiliza o princípio das correntes de Foucault, comumente conhecidas como correntes parasitas. O modelo do sistema é representado como um circuito elétrico equivalente composto por R1 e L1, respectivamente caracterizando a resistência e a indutância do circuito primário, as quais são conhecidas por uma bobina de excitação. Já no secundário, R2 e L2, estão representando a perda ôhmica e a indutância da amostra no qual as correntes parasitas são induzidas, além de outros dois componentes, M indutância mútua dos indutores acoplados e k, coeficiente relacionado ao acoplamento magnético entre os circuitos primário e secundário. A análise tradicionalmente utilizada para este tipo de medição é a avaliação da reflexão da impedância equivalente do circuito secundário representando a amostra no circuito primário. O trabalho analisa as equações de malha do circuito equivalente no domínio da frequência e identifica os parâmetros do modelo. A partir da identificação do sistema realizada com os ensaios experimentais, foi possível descobrir a constante de tempo indutiva τL do sistema. A partir dessa constante, observou-se a variação acentuada da mesma em relação a variação da impedância equivalente. Ainda é apresentada uma estimativa dos valores de R2 e L2 realizada por meio da unificação das informações obtidas com a identificação, aliada com as informações de campo magnético obtidas a partir de um sensor do tipo GMR e pela simulação em um software de elementos finitos COMSOL Multiphysics. / This work presents the study of a generic measurement system that uses the prin- ciple of eddy currents. The system model is represented as an equivalent electric circuit composed of R1 and L1 respectively characterizing the resistance and induc- tance of primary circuit, which are known by an excitation coil. In the secondary, R2 and L2 are representing the ohmic loss and the inductance of the sample in which the eddy currents are induced, in addition two other components, the mutual induc- tance of the coupled inductors and k, coefficient related to the magnetic coupling between the primary and secondary circuits. The analysis traditionally used for this type of measurement is the reflection evaluation of the equivalent impedance of the secondary circuit representing the sample in the primary circuit. The work analyzes the mesh equations of the equivalent circuit in the frequency domain and identifies the parameters of the model. From the identification of the system performed with the experimental tests, it was possible to discover the inductive time constant τL of the system. From this constant, it was observed the sharp variation of the same in relation to the variation of equivalent impedance. An estimate values, R2 and L2 performed by unification of the information obtained with the identification, to- gether with the magnetic field information obtained from a GMR type sensor and by simulation in a finite element software COMSOL Multiphysics.
49

Estudo de diferentes estruturas de grupos genéticos aditivos visando ao aumento da eficiência de seleção em bovinos de corte / Study of different additive genetic groups structures in order to increase the efficiency of genetic selection in beef cattle

Gerson Antônio de Oliveira Júnior 22 February 2013 (has links)
A estratégia de criação de grupos genéticos aditivos é uma técnica que permite que animais de paternidade desconhecida tenham seus valores genéticos preditos de forma mais adequada quando incluídos em programas de melhoramento genético. O modo como esses grupos são formados é ainda arbitrário, o que torna importante o estudo de metodologias de formação de grupos genéticos aditivos (GG) visando a uma estrutura apropriada para as avaliações dos rebanhos em programas de melhoramento genético animal. O objetivo do trabalho foi definir a estrutura de grupo genético adequada às avaliações genéticas, comparando-as em relação às mudanças efetivas na eficiência do processo seletivo dos animais com paternidade desconhecida. As características estudadas foram: peso ao desmame, peso ao sobreano, ganho de peso pós-desmama, perímetro escrotal ao sobreano e escore visual de musculosidade ao sobreano. Três cenários foram simulados a partir de um banco de dados composto apenas por animais com pedigree completo (grupo controle). O primeiro teve 30% dos animais com identificação de pai apagada, o segundo 50% e um terceiro com 70%. As estratégias de formação de GG foram: a fazenda de nascimento do animal com paternidade desconhecida; o ano de nascimento (SAFRA) e a concatenação de ano de nascimento e fazenda de nascimento (FAZSAFRA). Os componentes de variância foram calculados para o banco controle pelo software VCE e os valores genéticos foram preditos pelo software PEST, utilizando duas estruturas de modelo animal que se diferenciaram pela inclusão ou não do efeito fixo de GG. A definição da estrutura de grupo genético aditivo adequado à avaliação genética dos animais foi baseada na eficiência de seleção e na comparação entre os valores genéticos preditos quanto aos seus valores absolutos e quanto à classificação dos animais, sendo que animais do grupo controle foram assumidos como tendo o máximo em resposta à seleção genética. Os resultados demonstraram que os grupos genéticos aditivos proporcionam uma melhora na predição genética dos animais com paternidade desconhecida. As estratégias que proporcionaram valores mais próximos aos do grupo controle foram SAFRA e FAZSAFRA e, mesmo com similaridade de valores, a estratégia SAFRA foi superior na seleção dos melhores animais. / The structure of genetic groups is a technique that allows that animals with unknown paternity be included in breeding programs. The ways these groups are formed are still arbitrary, which makes it important to study formation methodologies of genetic groups aiming an appropriate framework for the evaluation of livestock in animal breeding programs. Therefore, the aim of this study was to define the structure of genetic group suited to genetic evaluations, comparing them regarding changes in the effective efficiency of the process of animals with unknown parentage. The characteristics studied were: weaning weight, post-weaning weight, post-weaning weight gain, scrotal circumference at 18 months of age and visual muscularity score at 18 months of age. Three scenarios were simulated from a database consisting only of complete pedigree animals (control group). The first had 30% of animals with identification of father off, the second with 50% and a third with 70%. The training strategies additive genetic groups were: the farm of birth of the animal with unknown parentage; birth year (SAFRA) and the concatenation of year of birth and birth farm (FAZSAFRA). The variance components were calculated for the data bank control program by VCE and breeding values were predicted using PEST software, with two structures of animal models that differ by the inclusion or not of the fixed effect of additive genetic group. The definition of the structure of genetic group suitable for genetic evaluation of animals was based on the efficiency of selection and comparison of estimated breeding values to the \"control\" breeding values and the classification of animals, while control animals were assumed to have the maximum response to selection whereas the choice of any other group of animals results in a reduction thereof. The results demonstrated that the additives genetic groups provide an improvement in the genetic prediction of animals with unknown paternity. Strategies that provided values closer to those of the control group were SAFRA and FAZSAFRA and even with similarity values, strategy SAFRA was superior in selecting the best animals.
50

Modelling and Simulation of Unknown Factors in Simulation Based Acquisition

Hultberg, Ida January 2002 (has links)
When a new product should be acquired, a model over its functionality is made. A quite new idea in the military area is to use simulations to find out what and how much to acquire. Since the product never has been on the market before it is hard to know how factors in the surroundings, like weather and other active objects, will affect it. Therefore these unknown factors that appear during the creation or acquiring of a new product need to be taken into consideration. A literature study is performed about how modelling of simulations can be done, and how unknown factors can be considered when modelling a simulation. The study goes into if unknown factors are taken into consideration when modelling in the Process component in Simulation Based Acquisition (SBA). The result of this study shows that SBA facilitates in the process of finding and reducing unknown factors.

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