Tesi sul tema "NDE test"

A hanseníase é uma doença infecciosa que acomete pele e nervos periféricos. Seu diagnóstico é baseado eminentemente nos seus aspectos clínicos variáveis e poucos são os exames complementares que auxiliam no diagnóstico, como baciloscopia do raspado intradérmico, histopatologia, ELISA anti- PGL1 (APGL1) e anti-LID, geralmente positivos nas formas multibacilares, dificultando o diagnóstico das formas paucibacilares. Busca-se comparar os resultados obtidos com o teste rápido imunológico (LID-NDO) Orange Life® com os resultados da PCR tempo real realizada nas amostras de raspado intradérmico e os resultados do ELISA APGL1 coletadas durante a ação por demanda espontânea (Hanseníase Brasília 2014), além de comparar eficiência entre dois métodos diferentes de conservação destas amostras (papel-filtro x álcool). Foram coletadas 277 amostras de raspado dérmico de 50 pacientes clinicamente diagnosticados com hanseníase durante a ação. Na mesma ocasião, os indivíduos diagnosticados foram submetidos à coleta de sangue periférico para teste rápido sorológico (Orange Life®) e ELISA APGL1. A extração de DNA do raspado intradérmico, armazenado no álcool e no papel-filtro, foi realizada no Laboratório de Dermatologia do HC-FMRP-USP. A PCR em tempo real foi realizada usando par de primers específicos RLEP, e o master mix sybr greenPromega. Dos 50 pacientes diagnosticados clinicamente, 90% são multibacilares. Todos os testes, tanto o teste rápido sorológico como a PCR, apresentaram maior positividade nos pacientes multibacilares. O teste rápido sorológico foi positivo em 64,44% dos pacientes multibacilares e em 40% dos paucibacilares. A PCR nas amostras armazenadas no álcool foi positiva em 19,05% dos pacientes multibacilares e a PCR do papel-filtro em 17,78%; nenhuma PCR foi positiva em pacientes paucibacilares. O ELISA APGL foi positivo em 56% dos pacientes diagnosticados. Na PCR das amostras armazenadas no papel-filtro, o sítio de coleta com maior positividade foram os cotovelos (75%). A concordância entre o teste rápido sorológico e a PCR e a concordância entre o teste rápido e o ELISA APGL1 foram fair (suave). Já a concordância entre a PCR das amostras armazenadas no álcool e a PCR das amostras armazenadas no papel-filtro foi perfeita. Concluímos que o exame clínico é ainda essencial para o diagnóstico da hanseníase, principalmente das formas paucibacilares. Os métodos de armazenamento do material coletado por raspado intradérmico (papel-filtro x álcool) não interferiram no resultado final da PCR, portanto o armazenamento no papel-filtro pode ser feito preferencialmente, pois apresenta menor custo para a extração de DNA. O teste rápido sorológico e o ELISA anti-PGL1 têm baixa especificidade, porém podem ter outras aplicações, diferentes do diagnóstico da hanseníase.
Leprosy is an infectious disease that affects skin and peripheral nerves. Leprosy diagnosis is mainly based on its variable clinical aspects and few complementary tests that aid in the diagnosis, such as bacilloscopy, histopathology, besides the antiPGL1 ELISA (APGL1) and anti-LID, all of which are generally positive in multibacillary forms, confirming the difficulty in diagnosis of paucibacillary patients. The aim of this study was to compare the results obtained with the Orange Life® Immunological Rapid Test (LID-NDO) with the real-time PCR results obtained in the intradermal scraping samples and the results of the ELISA APGL1, collected during the \"Hanseníase\" action in Brasília in January 2014, in addition to comparing efficiency between two different methods of preservation of these samples (filter paper x alcohol). A total of 277 dermal smear samples were collected from 50 patients clinically diagnosed with leprosy during the procedure. At the same time, the individuals diagnosed were submitted to peripheral blood collection for serological rapid test (Orange Life®) and ELISA APGL1. The extraction of DNA from intradermal scrapings, stored in alcohol and filter paper, was carried out at the Dermatology Laboratory of HC-FMRP-USP. Real-time PCR was performed using a pair of primers specific for the RLEP gene, and the master sybr green-Promega. From 50 patients diagnosed clinically, 90% are multibacillary. All tests, both the serological rapid test and the PCR, were more positive in multibacillary patients. The rapid serological test was positive in 64.44% of the multibacillary patients, and in 40% of the paucibacillary. The PCR in the samples stored in the alcohol was positive in 19.05% of the multibacillary patients and the PCR of the filter paper in 17.78%; PCR weren\'t positive in paucibacillary patients. ELISA APGL was positive in 56% (28) of the diagnosed patients. In the PCR of the samples stored in the filter paper, the collection site with the highest positivity was the elbows (75%). The agreement between the rapid serological test and the PCR and the agreement between the rapid test and the ELISA APGL1 were fair. The agreement between the PCR of the samples stored in the alcohol and the PCR of the samples stored on the filter paper was perfect. We conclude that the clinical examination is still essential for the diagnosis of leprosy, especially in paucibacillary forms. We also concluded that the methods of storing the material collected by intradermal scraping (filter paper x alcohol) do not interfere in the final result of the PCR, therefore the storage in the filter paper can be done preferentially because it presents a lower cost for the extraction of DNA. Rapid serological test and the anti-PGL1 ELISA have low specificity, but may have other different applications than the diagnosis of leprosy.

The diploma thesis deals with non-destructive testing of concrete as well as with the relationship between determined parameters and the compressive strength of concrete. The thesis is mainly focused on the ultrasonic pulse velocity method and the rebound hammer test. The experimental part of the thesis describes non-destructive tests performed on concrete blocks. The compressive strength was tested on the drill cores taken from the concrete blocks. The aim of this thesis is to find regression models of the relationship between the compressive strength and non-destructive parameters, and the subsequent analysis of the results.

Radiography is an extensively used NDT method, especially in nuclear, aerospace and automotive industries where optimal designs call for greater reliability. The rules corresponding to industrial radiography are defined in a system of radiographic standards. The standards related to the radiographic testing of metallic welded joints had been harmonised in all over the Europe and at the end in 1997, the standard "
EN 1435"
was established and published. Since then, this standard has become the most widely used standard where the radiographic applications are necessary. To eliminate the person based errors during application of the standard, moreover to save time, cost and effort in radiographic exposures, in this study it was aimed to write a computer program which is able to calculate all necessary parameters for a radiographic exposure related to this standard EN 1435. In the programming stage, Visual Basic 6.0 &
#61651
was used. The program consists of many windows, each giving and controlling separate parameters related to the exposure. Besides giving all the needed parameters, the evolved program is able to prepare a report with these parameters. So, both radiography technicians and experts can use it. It is believed that this study constructs a basis for developing other computerised test procedures for any kind of non-destructive testing methods used in industry today.

[EN] The test for determining the resonance frequencies has traditionally been used to investigate the mechanical integrity of concrete cores, to assess the conformity of concrete constituents in different accelerated durability tests, and to ascertain constitutive properties such as the elastic modulus and the damping factor. This nondestructive technique has been quite appealed for evaluation of mechanical properties in all kinds of durability tests. The damage evolution is commonly assessed from the reduction of dynamic modulus which is produced as a result of any cracking process. However, the mechanical behavior of concrete is intrinsically nonlinear and hysteretic. As a result of a hysteretic stress-strain behavior, the elastic modulus is a function of the strain. In dynamic tests, the nonlinearity of the material is manifested by a decrease of the resonance frequencies, which is inversely proportional to the excitation amplitude. This phenomenon is commonly referred as fast dynamic effect. Once the dynamic excitation ceases, the material undergoes a relaxation process whereby the elastic modulus is restored to that at rest. This phenomenon is termed as slow dynamics. These phenomena (fast and slow dynamics) find their origin in the internal friction of the material. Therefore, in cement-based materials, the presence of microcracks and interfaces between its constituents plays an important role in the material nonlinearity. In the context of the assessment of concrete durability, the damage evolution is based on the increase of hysteresis, as a result of any cracking process. In this thesis three different nondestructive techniques are investigated, which use impacts for exciting the resonant frequencies. The first technique consists in determining the resonance frequencies over a range of impact forces. The technique is termed Nonlinear Impact Resonant Acoustic Spectroscopy (NIRAS). It consists in ascertaining the downward resonant frequency shift that the material undergoes upon increasing excitation amplitude. The second technique consists in investigating the nonlinear behavior by analyzing the signal corresponding to a single impact. This is, to determine the instantaneous frequency, amplitude and attenuation variations corresponding to a single impact event. This technique is termed as Nonlinear Resonant Acoustic Single Impact Spectroscopy (NSIRAS). Two techniques are proposed to extract the nonlinear behavior by analyzing the instantaneous frequency variations and attenuation over the signal ring down. The first technique consists in discretizing the frequency variation with time through a Short-Time Fourier Transform (STFT) based analysis. The second technique consists of a least-squares fit of the vibration signals to a model that considers the frequency and attenuation variations over time. The third technique used in this thesis can be used for on-site evaluation of structures. The technique is based on the Dynamic Acousto- Elastic Test (DAET). The variations of elastic modulus as derived through NIRAS and NSIRAS techniques provide an average behavior and do not allow derivation of the elastic modulus variations over one vibration cycle. Currently, DAET technique is the only one capable to investigate the entire range of nonlinear phenomena in the material. Moreover, unlike other DAET approaches, this study uses a continuous wave source as probe. The use of a continuous wave allows investigation of the relative variations of the elastic modulus, as produced by an impact. Moreover, the experimental configuration allows one-sided inspection.
[ES] El ensayo de determinación de las frecuencias de resonancia ha sido tradicionalmente empleado para determinar la integridad mecánica de testigos de hormigón, en la evaluación de la conformidad de mezclas de hormigón en diversos ensayos de durabilidad, y en la terminación de propiedades constitutivas como son el módulo elástico y el factor de amortiguamiento. Esta técnica no destructiva ha sido ampliamente apelada para la evaluación de las propiedades mecánicas en todo tipo de ensayos de durabilidad. La evolución del daño es comúnmente evaluada a partir de la reducción del módulo dinámico, producido como resultado de cualquier proceso de fisuración. Sin embargo, el comportamiento mecánico del hormigón es intrínsecamente no lineal y presenta histéresis. Como resultado de un comportamiento tensión-deformación con histéresis, el módulo elástico depende de la deformación. En ensayos dinámicos, la no linealidad del material se manifiesta por una disminución de las frecuencias de resonancia, la cual es inversamente proporcional a la amplitud de excitación. Este fenómeno es normalmente denominado como dinámica rápida. Una vez la excitación cesa, el material experimenta un proceso de relajación por el cual, el módulo elástico es restaurado a aquel en situación de reposo. Este fenómeno es denominado como dinámica lenta. Estos fenómenos ¿dinámicas rápida y lenta¿ encuentran su origen en la fricción interna del material. Por tanto, en materiales basados en cemento, la presencia de microfisuras y las interfaces entre sus constituyentes juegan un rol importante en la no linealidad mecánica del material. En el contexto de evaluación de la durabilidad del hormigón, la evolución del daño está basada en el incremento de histéresis, como resultado de cualquier proceso de fisuración. En esta tesis se investigan tres técnicas diferentes las cuales utilizan el impacto como medio de excitación de las frecuencias de resonancia. La primera técnica consiste en determinar las frecuencias de resonancia a diferentes energías de impacto. La técnica es denominada en inglés: Nonlinear Impact Resonant Acoustic Spectroscopy (NIRAS). Ésta consiste en relacionar el detrimento que el material experimenta en sus frecuencias de resonancia, con el aumento de la amplitud de la excitación. La segunda técnica consiste en investigar el comportamiento no lineal mediante el análisis de la señal correspondiente a un solo impacto. Ésta consiste en determinar las propiedades instantáneas de frecuencia, atenuación y amplitud. Esta técnica se denomina, en inglés, Nonlinear Single Impact Resonant Acoustic Spectroscopy (NSIRAS). Se proponen dos técnicas de extracción del comportamiento no lineal mediante el análisis de las variaciones instantáneas de frecuencia y atenuación. La primera técnica consiste en la discretización de la variación de la frecuencia con el tiempo, mediante un análisis basado en Short-Time Fourier Transform (STFT). La segunda técnica consiste en un ajuste por mínimos cuadrados de las señales de vibración a un modelo que considera las variaciones de frecuencia y atenuación con el tiempo. La tercera técnica empleada en esta tesis puede ser empleada para la evaluación de estructuras in situ. La técnica se trata de un ensayo acusto-elástico en régimen dinámico. En inglés Dynamic Acousto-Elastic Test (DAET). Las variaciones del módulo elástico obtenidas mediante los métodos NIRAS y NSIRAS proporcionan un comportamiento promedio y no permiten derivar las variaciones del módulo elástico en un solo ciclo de vibración. Actualmente, la técnica DAET es la única que permite investigar todo el rango de fenómenos no lineales en el material. Por otra parte, a diferencia de otras técnicas DAET, en este estudio se emplea como contraste una onda continua. El uso de una onda continua permite investigar las variaciones relativas del módulo elástico, para una señal transito
[CAT] L'assaig de determinació de les freqüències de ressonància ha sigut tradicionalment empleat per a determinar la integritat mecànica de testimonis de formigó, en l'avaluació de la conformitat de mescles de formigó en diversos assajos de durabilitat, i en la terminació de propietats constitutives com són el mòdul elàstic i el factor d'amortiment. Esta tècnica no destructiva ha sigut àmpliament apel·lada per a l'avaluació de les propietats mecàniques en tot tipus d'assajos de durabilitat. L'evolució del dany és comunament avaluada a partir de la reducció del mòdul dinàmic, produït com resultat de qualsevol procés de fisuración. No obstant això, el comportament mecànic del formigó és intrínsecament no lineal i presenta histèresi. Com resultat d'un comportament tensió-deformació amb histèresi, el mòdul elàstic depén de la deformació. En assajos dinàmics, la no linealitat del material es manifesta per una disminució de les freqüències de ressonància, la qual és inversament proporcional a l'amplitud d'excitació. Este fenomen és normalment denominat com a dinàmica ràpida. Una vegada l'excitació cessa, el material experimenta un procés de relaxació pel qual, el mòdul elàstic és restaurat a aquell en situació de repòs. Este fenomen és denominat com a dinàmica lenta. Estos fenòmens --dinámicas ràpida i lenta troben el seu origen en la fricció interna del material. Per tant, en materials basats en ciment, la presència de microfissures i les interfícies entre els seus constituents juguen un rol important en la no linealitat mecànica del material. En el context d'avaluació de la durabilitat del formigó, l'evolució del dany està basada en l'increment d'histèresi, com resultat de qualsevol procés de fisuración. En esta tesi s'investiguen tres tècniques diferents les quals utilitzen l'impacte com a mitjà d'excitació de les freqüències de ressonància. La primera tècnica consistix a determinar les freqüències de ressonància a diferents energies d'impacte. La tècnica és denominada en anglés: Nonlinear Impact Resonant Acoustic Spectroscopy (NIRAS). Esta consistix a relacionar el detriment que el material experimenta en les seues freqüències de ressonància, amb l'augment de l'amplitud de l'excitació. La segona tècnica consistix a investigar el comportament no lineal per mitjà de l'anàlisi del senyal corresponent a un sol impacte. Esta consistix a determinar les propietats instantànies de freqüència, atenuació i amplitud. Esta tècnica es denomina, en anglés, Nonlinear Single Impact Resonant Acoustic Spectroscopy (NSIRAS). Es proposen dos tècniques d'extracció del comportament no lineal per mitjà de l'anàlisi de les variacions instantànies de freqüència i atenuació. La primera tècnica consistix en la discretización de la variació de la freqüència amb el temps, per mitjà d'una anàlisi basat en Short-Time Fourier Transform (STFT). La segona tècnica consistix en un ajust per mínims quadrats dels senyals de vibració a un model que considera les variacions de freqüència i atenuació amb el temps. La tercera tècnica empleada en esta tesi pot ser empleada per a l'avaluació d'estructures in situ. La tècnica es tracta d'un assaig acusto-elástico en règim dinàmic. En anglés Dynamic Acousto-Elastic Test (DAET). Les variacions del mòdul elàstic obtingudes per mitjà dels mètodes NIRAS i NSIRAS proporcionen un comportament mitjà i no permeten derivar les variacions del mòdul elàstic en un sol cicle de vibració. Actualment, la tècnica DAET és l'única que permet investigar tot el rang de fenòmens no lineals en el material. D'altra banda, a diferència d'altres tècniques DAET, en este estudi s'empra com contrast una ona contínua. L'ús d'una ona contínua permet investigar les variacions relatives del mòdul elàstic, per a un senyal transitori. A més, permet la inspecció d'elements per mitjà de l'accés per una sola cara.
Eiras Fernández, JN. (2016). Studies on nonlinear mechanical wave behavior to characterize cement based materials and its durability [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/71439
TESIS
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PROQUALI (UFJF)
A infecção subclínica pode ser avaliada por meio de teste sorológico, que determina imunoglobulinas circulantes. O objetivo do presente estudo foi analisar a reatividade de diferentes antígenos em casos novos de hanseníase, contatos domiciliares de casos e em população de área endêmica, com o intuíto de identificar o melhor antígeno para o diagnóstico sorológico da hanseníase e detecção de indivíduos infectados pelo Mycobacterium leprae. Trata-se de um estudo transversal de natureza exploratória e analítica. A reatividade anti-LID1, NDO-LID, NDO-HSA e PGL-1 foi avaliada por meio do enzyme-linked immunosorbent assay. Foram analisadas amostras de sangue total em papel de filtro Whatman de 2494 indivíduos da população de sete municípios da microrregião de Almenara e de soro de 94 casos novos de hanseníase e 104 contatos domiciliares de casos residentes no município de Uberlândia. O Banco de Dados foi criado no Software Epi Info versão 3.5.1 e análise realizada no software Statistical Package for the Social Sciences for Windows 18 e no GraphPad Prism versão 5. Para análise estatística foram utilizados os seguintes testes: Kolmogorov-Smirnov, Kruskal-Wallis one-way (H), Mann-Whitney (U) com correção de Bonferroni, kappa, Spearman (rho), teste Qui-quadrado de Pearson e regressão logística binária. Foi observado maior soropositividade no grupo de casos multibacilares (MB), em contatos domiciliares de casos MB e nos indivíduos residentes nos municípios de Almenara e Jequitinhonha. Obteve-se correlação positiva entre a sorologia e o índice baciloscópico, concordância substancial e significativa no grupo de casos novos de hanseníase e correlação positiva para todos os antígenos testados. Os testes anti-LID-1 e anti-NDO-LID apresentaram melhor performance para identificar os contatos domiciliares e ou indivíduos da população infectados pelo M. leprae. O PGL-1 nativo teve maior positividade do que o NDO-HSA para todas as formas clínicas da hanseníase e no grupo de contatos domiciliares. A prevalência de soropositividade na população foi superior à taxa de detecção de casos de hanseníase em todos os municípios avaliados. A faixa etária, a renda familiar, residir em município endêmico, conhecer alguém que teve ou tem hanseníase, ter ou ter tido caso de hanseníase na familia e residir ou ter residido com caso de hanseníase são fatores que podem explicar a diferença de soropositividade anti-NDO-LID. Apenas a faixa etária e conhecer alguém que teve ou tem hanseníase é capaz de explicar a diferença de soropositividade anti-NDO-HSA. E em relação ao LID-1 nenhuma variável foi explicativa. Todos os antígenos analisados podem auxiliar na diferenciação e caracterização da hanseníase MB e na identificação de indivíduos expostos ao M. leprae, porém o NDO-LID apresentou melhor performance na identificação desses indivíduos e dos casos paucibacilares, quando comparado aos testes envolvendo os antígenos LID-1 e NDO-HSA separadamente, portanto fornece benefício adicional a esses antígenos e poderia ser utilizado como ferramenta auxiliar na vigilância epidemiológica da hanseníase.
The subclinical infection can be evaluated by serologic test which determine circulating immunoglobulins. The aim of this study was to analyze the reactivity of different antigens in leprosy cases, household contacts of index cases and the population of the endemic area to identify the best antigen for the diagnosis of leprosy and detection of individuals infected with Mycobacterium leprae. It is a cross-sectional study of exploratory and analytical nature. The reactivity anti-LID-1, NDO-LID, NDO-HAS e PGL-1 were evaluated using the enzymelinked immunosorbent assay. The whole blood in Whatman filter paper of 2494 individuals from the general population of seven municipalities in the micro-Almenara and serum of 94 patients with leprosy and 104 household contacts of patients residing in Uberlândia were analyzed. The database was created in Epi Info software version 3.5.1 and analysis in the software Statistical Package for Social Sciences for Windows 18 and GraphPad Prism version 5. For statistical analysis the following tests were used: Kolmogorov-Smirnov, Kruskal Wallis one-way (H), Mann-Whitney (U) with Bonferroni correction, kappa, Spearman (rho), chisquare test of Pearson and binary logistic regression. Identied higher seropositivity in the group of MB patients, household contacts of MB patients and in individuals living in the municipalities of Almenara and Jequitinhonha. Observed positive correlation between serology test and bacterial index, substantial agreement and significant in patients positive and positive correlation for all antigens. The LID-1 and NDO-LID antigens showed greater ability to identify household contacts or the general population infected with M. leprae, but the performance of the NDO-LID was better. The native PGL-1 had higher seropositivity than the NDO-HSA for all clinical forms of leprosy and household contacts. The seropositivity prevalence in the general population was higher than the detection rate of leprosy cases in all evaluated municipalities. The age, family income, living in a city endemic, knowing someone who had or has leprosy, had or have the case in the family and live or lived with leprosy case are factors that can explain the anti-NDO-LID seropositivity difference. Only the age range and know someone who had or has leprosy is able to explain the anti-NDO-HSA seropositivity difference. And for the LID-1 no variable explained the anti-LID-1 seropositivity difference. All serological tests analyzed can assist in the differentiation and characterization of MB leprosy and the identification of individuals exposed to M. leprae, but NDO-LID performed better in identifying these individuals and PB patients, when compared to the tests involving the LID-1 and NDO-HSA antigens separately, therefore provides additional benefit to these antigens and could be used as an auxiliary tool in epidemiological surveillance of leprosy.

L'objectif de ce travail de thèse est d'étudier le comportement de l'endommagement des matériaux composites sous chargement statique et fatigue par contrôle non destructif (C.N.D) thermographie et soutenu par émission acoustique et la tomographie (CT scan). Pour cela, ce unidirectionnels composite à fibres de verre (GFRP) et discontinue composite à fibres de carbone (DCFC) ont été utilisés comme les éprouvettes qui ont fourni par PSA peugeot citröen, France. Une série d'essais mécaniques a été réalisée pour déterminer le comportement de l'endommagement sous chargement statique et fatigue. Pendant tout des essais mécanique, la thermographie a été utilisé pour l'observation en temps réel pour suivre l'évolution des températures sur la surface de l'éprouvette et supporté par émission acoustique dans certaines conditions. Cette étude a utilisé une forme rectangulaire et se compose d'éprouvettes trouées et non trouées au centre de l'éprouvette. La vitesse de déplacement constante est appliquée pour observer l'effet sur le comportement de l'endommagement sous chargement de traction statique. Sous les essais de fatigue, le paramètre constant de la fréquence et de l'amplitude de stress a été étudiée pour chaque niveau de charge pour avoir les propriétés de fatigue et l'évolution de l'endommagement de l'éprouvette. La tomographie a été utilisée pour confirmer l'apparition de l'endommagement et l'etat du matériau après l'essai de fatigue. L'analyse des résultats de l'expérimentation et de l'observation NDT montré le bon accord entre les résultats mechnical et NDT thermographie avec prise en charge par l'observation de l'émission acoustique en détecter l'apparition et la propagation de l'endommagement de GFRP PRV et DCFC sous chargement de statique en traction. Les essais en fatigue montrent que la dissipation thermique est liée à l'évolution de l'endommagement et également thermographie et peut être utilisé avec succès pour déterminer la limite d'endurance (HCFS) et la courbe de Wöhler du matériau composite. Les résultats par CT scan ont mesurée avec succès les endommagements et l'état du matériau après essai de fatigue du matériau composite
The aim of this study is to investigate the damage behaviour of composite material in static and fatigue condition with non destructive testing (NDT) thermography method and supported by acoustic emission and also computed tomography (CT) scan. Thermography and acoustic emission are used in real-time monitoring techniques during the test. On the other hand, NDT observation of tomography is used for a post-failure analysis. In order to achive this, continuous glass fiber composite (GFRP) and discontinuous carbon fiber composite (DCFC) have been used as the test specimens which supplied by PSA Company, France. A series of mechanical testing was carried out to determine the damage behaviour under static and fatigue loading. During all the mechanical testing, thermography was used in real-time observation to follow the temperature change on specimen surface and supported by acoustic emission in certain condition. This study used rectangular shape and consist of specimen with and without circular notches (hole) at the center. The constant displacement rate is applied to observe the effect on damage behaviour under tensile static loading. Under fatigue testing, the constant parameter of frequency and amplitude of stress was explored for each load level to have the fatigue properties and damage evolution of specimen. The tomography was used to confirm the appearance of damage and material condition after fatigue testing. The analysis from the experiment results and NDT observation shown the good agreement between mechnical results and NDT thermography with supported by acoustic emission observation in detect the appearance and propagation of damage for GFRP and DCFC under static loading. Fatigue testing shows that thermal dissipation is related to the damage evolution and also thermography and can be successfully used to determine high cycle fatigue strength (HCFS) and S-N curve of fiber composite material. From post failure analysis, CT scan analysis successfully measured and evaluated damage and material condition after fatigue test for fiber composite material. v

L’une des grandes problématiques actuelles des secteurs aéronautique et spatial est la réduction du taux d’émission de CO2. Une des solutions est l’allègement et l’optimisation des structures. Dans cette optique, certains avions comme l’a380 ou l’a350 XWB ont été fabriqués en grande partie à l’aide de matériaux composites. Plus résistants et plus légers, ils permettent un gain de poids important comparés aux matériaux métalliques. Cependant, ces pièces composites sont encore assemblées à l’aide de rivets ou de boulons. Ces procédés non adaptés aux matériaux composites limitent le gain de poids que pourrait engendrer leur utilisation. L’emploi de colles en revanche permettrait ce palier à ce problème, permettant ainsi de réduire de manière plus efficace le poids des structures. Cependant, ce procédé peut aussi être à l’origine de la création de joints faibles. Un joint est qualifié de faible quand sa tenue mécanique est inférieure à sa tenue nominale prévue. Actuellement, l’absence de Control Non Destructif (CND) permettant d’évaluer les propriétés mécaniques de ces pièces collées est l’un des principaux verrous à l’utilisation de ce procédé d’assemblage.Le Test d’Adhérence par Choc Laser (LASAT) a déjà prouvé sa capacité à évaluer la tenue mécanique de joints de colle dans des structure en Polymère Renforcé de Fibres de Carbone (PRFC). Cependant il ne peut s’appliquer qu’à quelques géométries d’assemblage spécifiques et a aussi démontré des limites en termes de détection de joint faible. Ce travail propose une étude expérimentale et numérique d’une des optimisations du LASAT : le Test d’Adhérence par Choc Laser Symétrique (S-LASAT). Le but est d’approfondir la compréhension de la physique mise en jeu afin de mieux appréhender les prérequis nécessaires à la technologie pour détecter les joints faibles. Cette étude conclura sur une étude unique de test d’adhérence réalisée sur de vraies pièce aéronautiques collées
The limitation of carbon dioxide emissions is one of today’s greatest challenges for the aerospace industry. Weight reduction is seen as one of the most promising lead for that matter and a first step has already been made toward this goal through the use of composite materials. Lighter and more mechanically efficient than their metallic counterparts, their use helped optimising the weight of several aircrafts such as the A350 XWB or A380. Nevertheless, if the material has changed, the assembly process did not evolve along with it. Hence, techniques such as riveting or bolting previously used for metallic structure are still used for composite parts assembly, but they are not suitable anymore for this type of material (creation of local constraints, corrosion, …). Instead, bonding composite parts using adhesives would be a better solution and could help further reducing the overall weight of the aircraft. However, with this new assembly method also come new problems, such as weak bonding. A weak bond is characterised by a loss of mechanical adherence that cannot be spotted using conventional Non-Destructive Tests (NDTs) such as ultrasound scanning. Since the industry currently lacks these NDTs to assess the mechanical integrity of bonded structures, the use of adhesives for composite assembly is limited.The LAser Shock Adhesion Test (LASAT), has already demonstrated its capacity to evaluate bonded composite assembly but also proved to be limited in terms of assembly configuration and weak bond detection capability. This work focuses on one of its optimisations, the Symmetrical LASAT (S-LASAT). Both experimental and numerical studies are realised to better understand the prerequisites of the technique as well as the level of mastery required for the technology to best detect weak bonds within Carbon Fibre Reinforce Polymer (CFRP) structures. This manuscript concludes with a one of a kind experimental campaign realised on real bonded CFRP aircraft parts

Civil Engineering
M.S.C.E.
Proper design of bridge structures requires an appreciation for the possible failure mechanisms that can develop over the lifetime of the bridge, many of which are related to natural hazards. For example, scour is one of the most common causes of bridge failures. Scour occurs due to the erosion of soil and sediment within a channel with flowing water. During a flood event, the extent of scour can be so great that it can destabilize an existing bridge structure. In order to evaluate the scour potential of a bridge, it is necessary to have information regarding the substructure, particularly the bridge foundations. However, as of 2011 there are more than 40,000 bridges across United States with unknown foundations. Generally for these bridges there are no design or as-built plans available to show the type, depth, geometry, or materials incorporated into the foundations. Several non-destructive testing (NDT) methods have been developed to evaluate these unknown foundations. The primary objective of this research is to identify the most current and widely used NDT methods for determining the embedment depth of unknown bridge foundations and to compare these methods to an ultrasonic P-wave reflection imaging system. The ultrasonic P-wave reflection system has tremendous potential to provide more information and address several short-comings of other NDT methods. A laboratory study was initiated to explore various aspects related to the P-wave system performance, in order to characterize the limitations of the system in evaluation of unknown foundations prior to deployment in field studies. Moreover, field testing was performed using the P-wave system and a number of the current NDT methods at two selected bridge foundations to allow comparison between the results.
Temple University--Theses

Nowadays, in Transport Asset Management, there is the need to identify measures to guarantee high levels of performance over time. The application of Non-Destructive Techniques, through high-efficiency equipment, turns out to be an optimal solution to ensure the quality of transport infrastructures. Asset Management take into account the importance of monitoring the performance characteristics of the transport infrastructures and QA/QC performance-based contracts specifications in order to guarantee the preservation of environmental, social and economic resources, as well. This study consists of two parts of research activity: in field tests and numerical simulations. The first part consists of in situ experimental activities to investigate both road and rail transport infrastructures. The tests have shown the versatility of high-performance instruments, such as FWD, LWD, GPR and ARAN, in railway monitoring, in the evaluation of ballast conditions and sleeper/ballast interaction, and also in the reuse of volcanic ashes that after stabilization can be used in road subbase layers. The high-efficiency equipment allow a faster execution of the tests with the possibility of a higher number of measurements, the combination of several instruments at the same time with a continuous mapping of the infrastructures, performance measures and a significant cost reduction. In the second part, the study focuses more specifically on road pavements. Considering several flexible pavements pulled out from the Italian Catalog, numerical simulations of FWD tests were carried out in the hypothesis of multilayer elastic theory with the aim to develop performance-based criteria and specifications for QC of pavement construction work. The results allow to estimate effects of structural deficits in the perspective of future performance and Life Cycle Cost Analysis in order to quantify penalties to restore expected higher maintenance costs.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Foram avaliados parâmetros clínicos, imunitários e epidemiológicos da vacinação contra a Doença de Newcastle em periquitos-australianos (Melopsittacus undulatus) através de dois experimentos. Foram utilizadas amostras vacinais Ulster 2C, B1 e La Sota do VDN. No experimento 1, foram utilizados 72 periquitos australianos com cinco meses de idade, distribuídos em 4 tratamentos de 18 animais cada, num total de três repetições, submetidos a diferentes esquemas imunoprofiláticos. A resposta imune foi avaliada pelo teste de HI, com posterior desafio frente a estirpe patogênica do VDN, aos 11 meses de vida das aves. Em todos os grupos, coletou-se suabes cloacais para pesquisa de RNA viral através da reação de cadeia de polimerase pós Transcrição Reversa (RT-PCR). Independente do grupo experimental, sinais clínicos da reação vacinal não foram observados. Os resultados dos títulos de anticorpos (HI) mostraram que os programas imunoprofiláticos ensaiados foram igualmente eficientes no estímulo da resposta imune humoral. Os periquitos-australianos desafiados mostraram-se refratários à enfermidade clínica com o VDN. Entretanto, ficou caracterizado o estado de portador de VDN nesta espécie decorridos até 19 dias da infecção experimental com este patógeno. No experimento 2, foram utilizadas aves SPF conviventes com periquitos-australianos inoculados com uma estirpe patogênica do VDN. Observou-se a transmissão de vírus patogênico (VDN) dos periquitos-australianos para as aves SPF conviventes decorridos até 19 dias da infecção experimental com este patógeno, o que vem realçar a importância do periquito-australiano como fonte potencial de infecção de VDN para aves domésticas
The clinical, epidemiological, immunological and parameters of vaccination against Newcastle disease in budgerigars (Melopsittacus undulatus) were investigated using 2 experiments. Ulster 2C, B1 and LaSota vaccines strains of the Newcastle disease virus (NDV) were used. In experiment 1, 72 budgerigars were used, and divided into 4 different groups with 18 birds per group. They were submitted to different vaccination programs. The immunological responses in these birds were measured by HI test. These birds were also challenged with a pathogenic VDN strain at 11 months of age. In all the groups, cloacal swabs were collected for RT-PCR. Independent of the group, clinical signs of reaction to the vaccine were not observed. The antibody titers (HI) results showed that the immune vaccine programs adopted were equally efficient in stimulating protective levels of humoral immune responses. Challenged budgerigars were refractory to the NDV clinical disease. However, a NDV carrier state was shown in this species until 19 days after experimental infection. In experiment 2, SPF chickens were housed with budgerigars which were previously inoculated with a pathogenic NDV strain. Therefore, the pathogenic virus (NDV) was transmitted from the budgerigars to SPF birds up to 19 days after challenge, showing the importance of the budgerigars as source of dissemination of NDV to domestic birds

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The addition of the food coloring plays an important role in the food industry under the technological point of view. Natural dyes are difficult to navigate in standard products, so we were created synthetic dyes. Among artificial synthetic dyes allowed by law, are those of azo group and its use is one of the most controversial developments in the sector. The use of these substances is still raising a lot of questions as to toxicity, because in the literature, working with this momentum is limited and controversial. In this context, the aim, with this study was to evaluate the genotoxic potential of azo dyes by the micronucleus assay (MN). The MN test is widely used and internationally accepted for evaluation of mutagenic actions. The in vivo genotoxicity test was applied to research observed in erythrocytes Polychromatic (PCE) extracted from the bone marrow of the femur 168 Swiss mice Albinus, male and female, underwent five treatments (N-nitroso-N-ethylurea: control+; 150 mM NaCl: Control–; dye at 1, 1.5 and 2 g.Kg-1) and used four azo dyes (Tartrazine, Sunset Yellow, Red 40, Ponceau 4R) for 24h and 48h (after this time euthanasia was performed). We analyzed also the PCE/NCE ratio, which it is an important marker of cytotoxicity. The data obtained in the MN assay were subjected to analysis of one-way variance (ANOVA) using a factorial scheme of 5 × 2 × 2 (treatment × sex × time), and average compared to Tukey's test (p < 0.05) using SAS® software version 9.3. The dye Tartrazine showed genotoxicity dose- and sex-dependent; Sunset Yellow was genotoxic sex-independent; Red 40, its genotoxicity was dependent on the exposure time and the sex of the animal; the dye Ponceau 4R genotoxicity depends on the dose and time until euthanasia. However, it can be concluded that studies of these food additives often must be performed in order to constantly update data that are safe for consumption, since all four dyes tested in this study showed some degree of toxicity. Recalling that they have the use regulated by specific legislation establishing the Maximum Allowable Limits (LMP) and patterns of Acceptable Daily Intake for humans, extrapolated to animals. However, despite the control required by regulatory agencies, the use of dyes in food continues to raise a number of questions, mainly due to lack of studies evaluating the toxicity of these compounds which reinforces the attention they should be given.
A adição de corantes em alimentos e rações assume papel importante na indústria alimentícia sob o ponto de vista tecnológico. Corantes naturais são difíceis de serem utilizados em produtos padronizados, portanto, foram criados corantes sintéticos. Dentre os corantes sintéticos artificiais permitidos por lei, estão aqueles do grupo Azo e seu uso é um dos avanços mais controversos no setor. A utilização destas substâncias continua levantando uma série de dúvidas quanto à toxicidade, uma vez que, na literatura, trabalhos com esse ímpeto são escassos e controversos. Neste contexto, objetivou-se, com este trabalho, avaliar o potencial genotóxico de corantes azóicos através do ensaio de micronúcleo (MN). O teste do MN é amplamente utilizado e aceito internacionalmente para avaliação de ações mutagênicas. O teste in vivo foi aplicado para investigação de genotoxicidade observada em Eritrócitos Policromáticos (PCE) extraídos da medula óssea do fêmur de 168 camundongos Swiss albinus, machos e fêmeas, submetidos a cinco tratamentos (N-Nitroso-N-etilureia: controle+; 150 mM NaCl: controle–; corante a 1, 1,5 e 2 g.Kg-1), sendo utilizados quatro corantes azóicos (Tartrazina, Amarelo Crepúsculo, Vermelho 40, Ponceau 4R) nos tempos de 24h e 48h (após estes períodos foi executada eutanásia). Foi analisada também a relação PCE/NCE, cujo se trata de um importante biomarcador de citotoxicidade. Os dados obtidos no ensaio de MN foram submetidos à análise de variância (ANOVA), utilizando um esquema fatorial de 5 × 2 × 2 (tratamento × sexo × tempo), e comparação das médias pelo teste de Tukey (p < 0,05) usando o programa computacional SAS® versão 9.3. O corante Tartrazina apresentou genotoxicidade dose e sexo dependentes; Amarelo Crepúsculo foi genotóxico independente do sexo; Vermelho 40, a sua genotoxicidade foi dependente do tempo de exposição e do sexo do animal; a genotoxicidade do corante Ponceau 4R foi dependente da dose administrada e do tempo até a eutanásia. Contudo, pode-se concluir que estudos envolvendo estes aditivos alimentares devem ser realizados frequentemente com a finalidade de atualização constante de dados que ofereçam segurança para seu consumo, uma vez que todos os quatro corantes testados nesta pesquisa apresentaram algum grau de toxicidade. Lembrando que os mesmos possuem o uso regulamentado por legislação específica, que estabelece os Limites Máximos Permitidos (LMP) e padrões de Ingestão Diária Aceitável por humanos, extrapolados para animais. Porém, apesar do controle exigido pelas agências reguladoras, a utilização de corantes em alimentos continua levantando uma série de dúvidas, principalmente devido a escassez de trabalhos avaliando a toxicidade destes compostos o que reforça a atenção que lhes deve ser conferida.

Orientador: Antonio Carlos Paulillo
Banca: Elizabeth Moreira dos Santos Schmidt
Banca: Adriano de Oliveira Torres Carrasco
Resumo: Foram avaliados parâmetros clínicos, imunitários e epidemiológicos da vacinação contra a Doença de Newcastle em periquitos-australianos (Melopsittacus undulatus) através de dois experimentos. Foram utilizadas amostras vacinais Ulster 2C, B1 e La Sota do VDN. No experimento 1, foram utilizados 72 periquitos australianos com cinco meses de idade, distribuídos em 4 tratamentos de 18 animais cada, num total de três repetições, submetidos a diferentes esquemas imunoprofiláticos. A resposta imune foi avaliada pelo teste de HI, com posterior desafio frente a estirpe patogênica do VDN, aos 11 meses de vida das aves. Em todos os grupos, coletou-se suabes cloacais para pesquisa de RNA viral através da reação de cadeia de polimerase pós Transcrição Reversa (RT-PCR). Independente do grupo experimental, sinais clínicos da reação vacinal não foram observados. Os resultados dos títulos de anticorpos (HI) mostraram que os programas imunoprofiláticos ensaiados foram igualmente eficientes no estímulo da resposta imune humoral. Os periquitos-australianos desafiados mostraram-se refratários à enfermidade clínica com o VDN. Entretanto, ficou caracterizado o estado de portador de VDN nesta espécie decorridos até 19 dias da infecção experimental com este patógeno. No experimento 2, foram utilizadas aves SPF conviventes com periquitos-australianos inoculados com uma estirpe patogênica do VDN. Observou-se a transmissão de vírus patogênico (VDN) dos periquitos-australianos para as aves SPF conviventes decorridos até 19 dias da infecção experimental com este patógeno, o que vem realçar a importância do periquito-australiano como fonte potencial de infecção de VDN para aves domésticas
Abstract: The clinical, epidemiological, immunological and parameters of vaccination against Newcastle disease in budgerigars (Melopsittacus undulatus) were investigated using 2 experiments. Ulster 2C, B1 and LaSota vaccines strains of the Newcastle disease virus (NDV) were used. In experiment 1, 72 budgerigars were used, and divided into 4 different groups with 18 birds per group. They were submitted to different vaccination programs. The immunological responses in these birds were measured by HI test. These birds were also challenged with a pathogenic VDN strain at 11 months of age. In all the groups, cloacal swabs were collected for RT-PCR. Independent of the group, clinical signs of reaction to the vaccine were not observed. The antibody titers (HI) results showed that the immune vaccine programs adopted were equally efficient in stimulating protective levels of humoral immune responses. Challenged budgerigars were refractory to the NDV clinical disease. However, a NDV carrier state was shown in this species until 19 days after experimental infection. In experiment 2, SPF chickens were housed with budgerigars which were previously inoculated with a pathogenic NDV strain. Therefore, the pathogenic virus (NDV) was transmitted from the budgerigars to SPF birds up to 19 days after challenge, showing the importance of the budgerigars as source of dissemination of NDV to domestic birds
Mestre

Pour évaluer la résistance mécanique du béton dans un ouvrage existant, la méthodologie courante combine des mesures non destructives (CND) comme le rebond ou/et la vitesse des ondes ultrasoniques avec la technique destructive (carottes) afin de produire une relation‘‘modèle de conversion” entre la résistance mécanique et les mesures CND. Le modèle de conversion est utilisé pour estimer la valeur locale de résistance mécanique à chaque emplacement de test en utilisant la valeur CND correspondante. Ensuite, on calcule les estimations de la résistance moyenne et/ou de l’écart-type de la résistance (variabilité de la résistance du béton). Cependant, la fiabilité d’estimation est toujours discutable en raison des incertitudes associées à l’évaluation de la résistance basée sur les mesures CND. Pour améliorer la fiabilité, les incertitudes doivent être réduites en spécifiant et en contrôlant leurs facteurs d’influence. Par conséquent, l’objectif de cette thèse est d’analyser la méthodologie d’évaluation courante afin de fournir des recommandations pratiques qui peuvent améliorer la fiabilité de l’évaluation de la résistance in-situ du béton dans les ouvrages existantes par des tests non destructifs et des carottes.Pour ce but, un simulateur a été construit afin d’analyser les effets des facteurs les plus influents en utilisant une vaste campagne de données provenant de sources différentes (études in situ ou en laboratoire et données synthétiques générées). La première contribution de ce travail est le développement d’une nouvelle approche d’identification du modèle ‘‘bi-objectif” qui peut efficacement capturer la variabilité de la résistance mécanique en plus de la moyenne. Après avoir étudié l’effet du mode de sélection des emplacements pour les carottes, une méthode a été proposée pour sélectionner ces emplacements en fonction des mesures CND ‘‘sélection conditionnelle” qui améliore la qualité de l’évaluation sans coût supplémentaire. Une dernière innovation est l’établissement de courbes de risque qui quantifient la relation entre le nombre de carottes et la précision de l’estimation. Enfin, des recommandations ont été formulées afin de fournir des estimations plus fiables
To assess concrete strength in an existing structure, the current methodology combines nondestructive measurements (NDT) like rebound hammer or/and pulse velocity with destructive technique (cores) in order to implement a relationship ‘‘conversion model” between the compressive strength and NDT measurements. The conversion model is used to estimate the local strength value at each test location using the corresponding NDT value.Then the estimated mean strength and/or estimated strength standard deviation (concrete strength variability) values are calculated. However, the reliability of these estimated values isalways a questionable issue because of the uncertainties associated with the strength assessment based upon NDT measurements. To improve the reliability, the uncertainties must be reduced by specifying and controlling their influencing factors. Therefore, the objective of this thesis is to analyze the current assessment methodology in order to provide practical recommendations that can improve the reliability of assessing the in-situ strength in existing concrete structures by nondestructive tests and cores.To this end, a simulator was built in order to analyze the effects of the most influencing factors using a large campaign of datasets from different sources (in-situ or laboratory studies,and generated synthetic data).The first contribution of this work is the development of a new model identification approach“bi-objective” that can efficiently capture the strength variability in addition to the mean strength. After studying the effect of the way of selection the core locations, a method was proposed to select these locations depending on the NDT measurements “conditional selection” that improves the quality of assessment without additional cost. A third innovation was the development of a procedure to identify the relation between the number of cores and the accuracy of the estimation. Finally recommendations were derived in order to providemore reliable estimated values

L’évaluation des performances des procédures de Contrôle Non Destructifs (CND) en aéronautique est une étape clé dans l’établissement du dossier de certification de l’avion. Une telle démonstration de performances est faite à travers l’établissement de probabilités de détection (Probability Of Detection – POD), qui intègrent l’ensemble des facteurs influents et sources d’incertitudes inhérents à la mise en œuvre de la procédure. Ces études, basées sur des estimations statistiques faites sur un ensemble représentatif d’échantillons, reposent sur la réalisation d’un grand nombre d’essais expérimentaux (un minimum de 60 échantillons contenant des défauts de différentes tailles, qui doivent être inspectés par au moins 3 opérateurs [1]), afin de recueillir un échantillon suffisant pour une estimation statistique pertinente. Le coût financier associé est élevé, parfois prohibitif, et correspond majoritairement à la mise en œuvre des maquettes servant aux essais. Des travaux récents [2-5] ont fait émerger une approche de détermination de courbes POD utilisant la simulation des CND, notamment avec le logiciel CIVA. L’approche, dite de propagation d’incertitudes, consiste à : - Définir une configuration nominale d’inspection, - Identifier l’ensemble des paramètres influents susceptibles de varier dans l’application de la procédure, - Caractériser les incertitudes liées à ces paramètres par des lois de probabilités, - Réaliser un grand nombre de simulations par tirage aléatoire des valeurs prises par les paramètres variables selon les lois de probabilités définies. Le résultat de cet ensemble de simulations constitue enfin la base de données utilisée pour l’estimation des POD. Cette approche réduit de façon très importante les coûts d’obtention des POD mais est encore aujourd’hui sujette à discussions sur sa robustesse vis-à-vis des données d’entrée (les lois de probabilité des paramètres incertains) et sur la prise en compte des facteurs humains. L’objectif de cette thèse est de valider cette approche sur des cas d’application AIRBUS et d’en améliorer la robustesse afin de la rendre couramment utilisable au niveau industriel, notamment en la faisant accepter par les autorités de vol (FAA et EASA). Pour ce faire le thésard devra mener des campagnes de validations des codes de simulation des CND, mettre en œuvre la méthodologie décrite plus haut sur les cas d’application AIRBUS, puis proposer et mettre en œuvre des stratégies d’amélioration de la robustesse de la méthode vis-à-vis des données d’entrée et des facteurs liés à l’humain
The performance assessment of non-destructive testing (NDT) procedures in aeronautics is a key step in the preparation of the aircraft's certification document. Such a demonstration of performance is done through the establishment of Probability of Detection (POD) laws integrating all sources of uncertainty inherent in the implementation of the procedure. These uncertainties are due to human and environmental factors in In-Service maintenance tasks. To establish experimentally these POD curves, it is necessary to have data from a wide range of operator skills, defect types and locations, material types, test protocols, etc. Obtaining these data evidences high costs and significant delays for the aircraft manufacturer. The scope of this thesis is to define a robust methodology of building POD from numerical modeling. The POD robustness is ensured by the integration of the uncertainties through statistical distributions issued from experimental data or engineering judgments. Applications are provided on titanium beta using high frequency eddy currents NDT technique. First, an experimental database will be created from three environments: laboratory, A321 aircraft and A400M aicraft. A representative sample of operators, with different certification levels in NDT technique, will be employed. Multiple inspection scenarios will be carried out to analyze these human and environmental factors. In addition, this study will take into account the impact of using different equipments in the HFEC test. This database is used, subsequently, to build statistical distributions. These distributions are the input data of the simulation models of the inspection. These simulations are implemented with the CIVA software. A POD module, based on the Monte Carlo method, is integrated into this software. This module will be applied to address human and ergonomic influences on POD. Additionally this module will help us to understand in a better way the equipment impact in POD curves. Finally, the POD model will be compared and validated with the experimental results developed

Longitudinal joints are one of the critical factors that cause premature pavement failure. Poor-quality joints are characterized by a low density and high permeability; which generates surface distresses such as ravelling or longitudinal cracking. Density has been traditionally considered as the primary performance indicator of joint construction. Density measurements consist of taking cores in the field and determining their density in the laboratory. Although this technique provides the most accurate measure of joint density, it is destructive and time consuming. Nuclear and non-nuclear gauges have been used to evaluate the condition of longitudinal joint non-destructively, but did not show good correlation with core density tests. Consequently, agencies are searching for other non-destructive testing (NDT) options for longitudinal joints evaluation. NDT methods have significantly advanced for the evaluation of pavement structural capacity during the past decade. These methods are based either on deflection or wave velocity measurements. The light weight deflectometer (LWD) is increasingly being used in quality control/quality assurance to provide a rapid determination of the surface modulus. Corresponding backcalculation programs are able to determine the moduli of the different pavement layers; these moduli are input parameters for mechanistic-empirical pavement design. In addition, ultrasonic wave-based methods have been studied for pavement condition evaluation but not developed to the point of practical implementation. The multi-channel analysis of surface waves (MASW) consists of using ultrasonic transducers to measure surface wave velocities in pavements and invert for the moduli of the different layers. In this study, both LWD and MASW were used in the laboratory and in the field to assess the condition of longitudinal joints. LWD tests were performed in the field at different distances from the centreline in order to identify variations of the surface modulus. MASW measurements were conducted across the joint to evaluate its effect on wave velocities, frequency content and attenuation parameters. Improved signal processing techniques were used to analyze the data, such as Fourier Transform, windowing, or discrete wavelet transform. Dispersion curves were computed to determine surface wave velocities and identify the nature of the wave modes propagating through the asphalt pavement. Parameters such as peak-to-peak amplitude or the area of the frequency spectrum were used to compute attenuation curves. A self calibrating technique, called Fourier transmission coefficient (FTC), was used to assess the condition of longitudinal joints while eliminating the variability introduced by the source, receivers and coupling system. A critical component of this project consisted of preparing an asphalt slab with a joint in the middle that would be used for testing in the laboratory. The compaction method was calibrated by preparing fourteen asphalt samples. An exponential correlation was determined between the air void content and the compaction effort applied to the mixture. Using this relationship, an asphalt slab was prepared in two stages to create a joint of medium quality. Nuclear density measurements were performed at different locations on the slab and showed a good agreement with the predicted density gradient across the joint. MASW tests were performed on the asphalt slabs using different coupling systems and receivers. The FTC coefficients showed good consistency from one configuration to another. This result indicates that the undesired variability due to the receivers and the coupling system was reduced by the FTC technique. Therefore, the coefficients were representative of the hot mix asphalt (HMA) condition. A comparison of theoretical and experimental dispersion curves indicated that mainly Lamb waves were generated in the asphalt layer. This new result is in contradiction with the common assumption that the response is governed by surface waves. This result is of critical importance for the analysis of the data since MASW tests have been focusing on the analysis of Rayleigh waves. Deflection measurements in the field with the LWD showed that the surface modulus was mostly affected by the base and subgrade moduli, and could not be used to evaluate the condition of the surface course that contains the longitudinal joints. The LWDmod software should be used to differentiate the pavement layers and backcalculate the modulus of the asphalt layer. Testing should be performed using different plate sizes and dropping heights in order to generate different stress levels at the pavement surface and optimize the accuracy of the backcalculation. Finally, master curves were computed using a predictive equation based on mix design specifications. Moduli measured at different frequencies of excitation with the two NDT techniques were shifted to a design frequency of 25 Hz. Design moduli measured in the field and in the laboratory with the seismic method were in good agreement (less than 0.2% difference). Moreover, a relatively good agreement was found between the moduli measured with the LWD and the MASW method after shifting to the design frequency. In conclusion, LWD and MASW measurements were representative of HMA condition. However, the condition assessment of medium to good quality joints requires better control of the critical parameters, such as the measurement depth for the LWD, or the frequency content generated by the ultrasonic source and the coupling between the receivers and the asphalt surface for the MASW method.

Tese de Doutoramento em Engenharia Civil - Ramo de Conhecimento em Estruturas
O trabalho apresentado nesta tese foi desenvolvido no Departamento de Engenharia Civil da Universidade do Minho e no Departamento de Engenharia Estrutural do Politécnico de Milão, Itália. A prática moderna na conservação de edifícios históricos é uma tarefa complexa que requer um diagnóstico profundo e cuidadoso. A investigação preliminar é essencial afim de intervir correctamente e com sucesso. Os objectivos dessa investigação são recolher de informação apropriada sobre o edifício ou a estrutura, e avaliar as propriedades mecânicas dos materiais, sendo esta última uma tarefa difícil devido à complexidade de materiais e alvenarias antigos. É imprescindível conhecer o estado de conservação da estrutura, a extensão dos danos, a ocorrência de humidades, a geometria e características escondidas tais como vazios, fendas e destacamentos. Com o intuito de aumentar o conhecimento sobre materiais de construção antigos, foi efectuada a caracterização de tijolos cerâmicos provenientes de seis mosteiros Portugueses do século XII a XIX. Os resultados mostraram uma grande dispersão, evidenciando as seguintes características: porosidade e sucção elevadas e resistência à compressão baixa. A composição química indica que estes tijolos não foram fabricados com o mesmo tipo de matéria-prima que os artefactos antigos de cerâmica. As restrições à remoção de material para efeitos de amostragem ou para a realização de testes destrutivos são muito elevadas. Assim, nas últimas décadas, o uso de técnicas não destrutivas para investigação e diagnóstico de edifícios históricos aumentou de maneira significativa. No entanto, a avaliação da resistência à compressão e doutras propriedades mecânicas dos materiais antigos utilizando técnicas não destrutivas permanece um desafio. Uma metodologia semi-destrutiva recente baseada na microperfuração é apresentada neste trabalho para a caracterização de tijolos cerâmicos dos séculos XII a XIX. Os resultados mostram que é possível estimar de maneira fiável a resistência à compressão dos tijolos através de curvas de regressão usando a técnica de microperfuração adoptada neste trabalho. A substituição de materiais de construção antigos é um tema relevante para o património arquitectónico. Os materiais modernos são geralmente incompatíveis, exibindo uma resistência e um módulo de elasticidade muito mais elevados. Assim, este trabalho também inclui o estudo de tijolos fabrico tradicional, e que se destinam à substituição de tijolos antigos. Este estudo mostra que os tijolos modernos são mais duráveis mas evidenciam uma resistência à compressão semelhante. Além disso, as correlações propostas anteriormente para a resistência à compressão permanecem válidas para os tijolos modernos de fabrico tradicional. Estava prevista a construção de réplicas de paredes de alvenaria antigas com recurso aos tijolos modernos de fabrico tradicional e argamassa de cal de baixa resistência, com vazios e outras inclusões colocados no seu interior. Essas paredes seriam testadas utilizando outra técnica não destrutiva, que não se encontra facilmente disponível em Portugal. O Radar de Prospecção Geotécnica é uma técnica de investigação não destrutiva que permite detectar alterações de materiais através das suas propriedades dieléctricas. O Radar de Prospecção Geotécnica foi empregue na determinação da geometria e na detecção de características escondidas em elementos de alvenaria tais como vazios, fendas e destacamentos. A determinação dessas características é essencial devido ao elevado grau de heterogeneidade das estruturas antigas e às implicações destas no desempenho estrutural dos edifícios. Assim, através duma série de exemplos em provetes laboratoriais e in situ, o Radar de Prospecção Geotécnica foi usado para ajudar na detecção de características geométricas e para encontrar elementos metálicos e vazios em alvenaria histórica. Os ensaios em provetes laboratoriais incluem duas paredes de três panos em alvenaria de pedra para avalização geométrica dos panos exteriores, detecção de vazios e elementos de madeira, e uma terceira parede de alvenaria mais complexa, construída com um número significativo de deficiências, diferentes materiais (tijolo e pedra) e elementos com diferente geometria, simulando situações comuns em edifícios históricos. Os ensaios in situ, foram efectuados em diversos monumentos antigos localizados em vários países Europeus para avaliar o desempenho da técnica numa série de aplicações distintas. A medição no modo de reflexão (2D) com o Radar de Prospecção Geotécnica foi efectuada em todos os casos e produziu resultados satisfatórios relativamente à avaliação das características geométricas dos painéis de alvenaria assim como na localização de outras características (vazios, fendas, destacamentos) e objectos (elementos em madeira e metálicos) que se encontram frequentemente em elementos estruturais alvenaria. Técnicas de aquisição mais precisas e rotinas de processamento de sinais mais avançadas foram utilizadas quando é necessário um posicionamento mais preciso e para a avaliação das dimensões de prováveis objectos. Aquisições para a obtenção de volumes 3D foram efectuadas, permitindo obter o posicionamento tridimensional de vazios cilíndricos, de barras de aço e dum balaústre de betão. No entanto, esta técnica não reproduziu com suficiente precisão as dimensões dos objectos devido, essencialmente, à resolução da antena quando comparado com as dimensões do respectivo objecto. Para detectar camadas de pequena espessura na alvenaria, de difícil detecção através de perfis 2D em reflexão, foram efectuadas medições em modo de transmissão. A partir dos resultados dos tomogramas foi possível distinguir o material deteriorado do material são. Devido à grande quantidade de dados necessária, ao tempo dispendido durante a aquisição no local e aos recursos informáticos elevados para aplicar os algoritmos de reconstrução 3D e tomografia, essas técnicas apenas podem ser aplicadas localmente, caso as aquisições normais em modo de reflexão não permitam obter a informação necessária.
The work presented in this thesis has been developed at the Department of Civil Engineering of University of Minho, Portugal, and at the Department of Structural Engineering of Polytechnic of Milan, Italy. Modern practice in conservation of historical buildings is a complex task that requires a deep and careful diagnosis. Preliminary investigation is essential in order to intervene correctly and successfully. The objectives of such investigation are to gather adequate information about the building or structure, and to evaluate the mechanical properties of materials, being the latter a difficult task due to the complexity of old materials and historic fabrics. Necessary information is the state of conservation, the extent of damages, the presence of moisture, the geometry and hidden features such as voids, cracks and detachments. In order to increase the knowledge about ancient building materials, characterization of clay brick from historic monuments in Portugal was performed in bricks from the 12th to 19th century, collected from six monasteries. The results showed a large scatter, and the main characteristics are high porosity, high suction and low compressive strength. Chemical composition indicates that bricks are not prepared with the same raw materials as old clay artefacts. The restrictions to remove material for mechanical sampling or to carry out destructive tests are very large. Therefore, in the last decades, the use of non-destructive testing techniques for investigation and diagnosis of historical buildings has increased significantly. However, the evaluation of the compressive strength and other mechanical properties of historic materials using such techniques remains a challenge. A recent minor-destructive methodology based on microdrilling is used in this research work for the characterization of clay bricks from the 12th to 19th century. The results show that it is possible to reliably estimate the compressive strength of bricks by means of regression curves using the adopted microdrilling technique. The replacement of old material is a matter of concern in every intervention in architectural heritage. Modern materials are usually incompatible, as they present much higher strength and elastic modulus. Thus, this work addresses also the study of traditional handmade clay bricks as replacing bricks. The study shows that new bricks are more durable but exhibit comparable compressive strength. Moreover, the proposed correlations for compressive strength of ancient bricks remain valid for new traditional handmade clay bricks. Originally, it was planned to use new handmade bricks and weak lime mortars to build replicas of ancient masonry walls, with voids and other inclusions. These would be tested using another technique, which is fully non-destructive and not easily available in Portugal. Ground Penetrating Radar is a non-destructive technique that allows the detection of material changes through changes in dielectric properties. Ground Penetrating Radar was used to determine the geometry and to map hidden features of masonry such as voids, cracks and detachments. The detection of these properties is of high relevance due to the high heterogeneity of old structures, which has implications in the structural performance of buildings. Thus, through a series of examples in laboratory specimens and in situ, the Ground Penetrating Radar was used to help in the detection of geometrical characteristics and to find metallic elements and voids in masonry. The tests in laboratory specimens included two three-leaf stone masonry walls for the geometrical assessment of the exterior panels, the detection of voids and embedded wood beams, and a third complex stone/masonry wall built with a significant amount of deficiencies, construction materials and elements with different geometry, simulating typical situations on historical buildings. The experiments in situ were performed in several masonry monuments from different European countries to assess the performance of the technique for a number of applications. Radar measurements in reflection mode (2D) were carried out in every case and produced satisfactory results regarding geometry assessment of masonry leaves and in the location of features (air voids, cracks, detachments) and objects (wood beams, steel objects) that are often found in masonry structural elements. More precise acquisition techniques and advanced signal processing routines were used when more accurate positioning was needed and for the assessment of the dimensions of possible objects. Acquisitions for the construction of advanced 3D volumes were performed and allowed to obtain the three-dimensional position of cylindrical voids, steel bars and concrete baluster. However, the technique failed to reproduce adequately the dimensions of the objects due, essentially, to the resolution of the antenna when compared to the dimensions of the targets. Transmission measurements were performed to detect thin layers of masonry. The resultant tomograms identify damaged and undamaged material. Due to the significant amount of data that is necessary, the time for accurate field acquisition and the large computer resources to run 3D reconstruction and inversion algorithms, these techniques can only be applied locally, if typical 2D radargrams do fail to provide the necessary information.
Fundação para a Ciência e a Tecnologia (FCT)

碩士
國立臺灣大學
財務金融學研究所
87
First, this study adopts the Cointegration and Error Correction Model to investigate the price discovery function of N.T./U.S. dollar non-delivery forward (NDF). The result of the study indicates that the NDF as well as the spot rate series for the NT dollar are non-stationary, but the NDF rates of the NT dollar are cointegrated with the spot rates of the NT dollar. In other words, in the long run, the NDF and spot rates of the NT dollar converge to stable equilibrium. On the other hand, there exists feedback relationship between the NDF and spot rate of the NT dollar, in the short run. Second, this study employs the conditional variance from GARCH(1,1) model as the proxy of volatility of the exchange rate series. Furthermore, this study also adopts the vector autoregressive(VAR) model to investigate the relationship between NDF trading activity and the volatility in the spot rate of the NT dollar. Based on the Granger Causality test, we find that the conditional variance of the spot rates of the NT dollar is not affected by the NT NDF daily trading volume. Third, based on Granger (1969), the conditional variance of the spot rates of the NT dollar is affected by the conditional variance of the NDF rates of the NT dollar. Probably due to the lower transaction costs and better market liquidity, NDF market reacts faster to the information than cash market does. Therefore, the volatility change of the NDF rate of the NT dollar leads the volatility change of the spot rate of the NT dollar.

Dissertação de Mestrado apresentada ao Instituto Superior de Psicologia Aplicada para obtenção de grau de Mestre na especialidade de Psicologia Clínica.
O presente estudo teve como objectivo primordial obter valores normativos, para uma população com Necessidades Educativas Especiais (NEE) do Concelho de Vila de Franca de Xira e compará-los com os já aferidos para a população do Concelho de Loures, do Teste Comprehensive Test of Nonverbal Intelligence (CTONI; Hammill, Pearson & Wiederholt, 1996), de acordo com a idade, escolaridade e género. Estudou-se uma amostra de 120 sujeitos (63 do sexo masculino e 57 do sexo feminino), com idades compreendidas entre os 9 e os 12 anos que frequentavam os 4º e 5ºanos do Ensino básico. Não se verificam diferenças significativas no que concerne à idade, escolaridade e género, na nossa amostra. Foi elaborada uma Tabela de valores médios que concilia o desempenho dos sujeitos consoante a idade. Os resultados foram interpretados de acordo com a literatura e foram ainda apresentadas sugestões para futuras investigações com este Teste.
The main goal of this study was to obtain normative data based on a population with Educational Special Necessities (NEE) of Vila de Franca de Xira and compare them with a previous study of Loures’s population with the Comprehensive Test of Nonverbal Intelligence (CTONI; Hammill, Pearson & Wiederholt, 1996), according to age, education and gender. A sample of 120 subjects was studied (63 male and 57 female), with ages between 9 and 12 years and they were in 4th and 5th grade. Age, education and gender significant differences were not found in our sample. The results were understood according to the literature revised and suggestions for future studies with those tests were made.