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1

Kumar, Hara. "Dynamic First Match : Reducing Resource Consumption of First Match Queries in MySQL NDB Cluster." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-289594.

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Dynamic First Match is a learned heuristic that reduces the resource consumption of first match queries in a multi-threaded, distributed relational database, while having a minimal effect on latency. Traditional first match range scans occur in parallel across all data fragments simultaneously. This could potentially return many redundant results. Dynamic First Match reduced this redundancy by learning to scan only a portion of the data fragments first, before scanning the remaining fragments with a pruned data set. Benchmark tests show that Dynamic First Match could reduce resource consumption of first match queries containing first match range scans by over 40% while having a minimal effect on latency.
Dynamisk Första Match är en lärd heuristik som minskar resursförbrukningen för första match frågor i en flertrådad och distribuerad relationsdatabas, samtidigt som den har en minimal effekt på latens. Första match frågor resulterar i många intervallavsökningar. Traditionellt intervallskanningarna körs parallellt över alla datafragment samtidigt. Detta kan potentiellt ge många överflödiga resultat. Dynamisk Första Match minskade denna redundans genom att lära sig att bara skanna en del av datafragmenten innan återstående datafragmenten skannades med en beskuren datamängd. Jämförelsetester visar att Dynamisk Första Match kan minska resursförbrukningen för första match frågor med intervallavsökningar med över 40% samtidigt som den har en minimal effekt på latens.
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2

Volminger, Alexander. "A comparison of Data Stores for the Online Feature Store Component : A comparison between NDB and Aerospike." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-295497.

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This thesis aimed to investigate what Data Stores would fit to be implemented as an Online Feature Store. This is a component in the Machine Learning infrastructure that needs to be able to handle low latency Reads at high throughput with high availability. The thesis evaluated the Data Stores with real feature workloads from Spotify’s Search system. First an investigation was made to find suitable storage systems. NDB and Aerospike were selected because of their state-of-the-art performance together with their suitable functionality. These were then implemented as the Online Feature Store by batch Reading the feature data through a Java program and by using Google Dataflow to input data to the Data Stores. For 1 client NDB achieved about 35% higher batch Read throughput with around 30% lower P99 latency than Aerospike. For 8 clients NDB got 20% higher batch Read throughput, with a varying P99 latency different compared to Aerospike. But in a 8 node setup NDB achieved on average 35% lower latency. Aerospike achieved 50% fasterWrite speeds when writing feature data to the Data Stores. Both Data Stores’ Read performance was found to suffer upon Writing to the data store at the same time as Reading, with the P99 Read latency increasing around 30% for both Data Stores. It was concluded that both Data Stores would work as an Online Feature Store. But NDB achieved better Read performance, which is one of the most important factors for this type of Feature Store.
Den här uppsatsen undersökte vilka datalagringssystem som passar för att implementeras som en Online Feature Store. Detta är en komponent i maskininlärningsinfrastrukturen som måste hantera snabba läsningar med hög genomströmning och hög tillgänglighet. Uppsatsen studerade detta genom att evaluera datalagringssystem med riktig feature data från Spotifys söksystem. En utredning gjordes först för att hitta lovande datalagringssystem för denna uppgift. NDB och Aerospike blev valda på grund av deras topp prestanda och passande funktionalitet. Dessa implementerades sedan som en Online Feature Store genom att batch-läsa feature datan med hjälp av ett Java program samt genom att använda Google Dataflow för att lägga in feature datan i datalagringssystemen. För 1 klient fick NDB runt 35% bättre genomströmning av feature data jämfört med Aerospike för batch läsningar, med ungefär 30% lägre P99 latens. För 8 klienter fick runt 20% högre genomströmning av feature data med en P99 latens som var mer varierande. Men klustren med 8 noder fick NDB i genomsnitt 35% lägre latens. Aerospike var 50% snabbare på att skriva feature datan till datalagringssystemet. Båda systemen led dock av sämre läsprestanda när skrivningar skedde till dem samtidigt. P99 läs-latensen gick då upp runt 30% för båda datalagringssystemen. Sammanfattningsvis funkade båda av de undersökta datalagringssystem som en Online Feature Store. Men NDB hade bättre läsprestanda, vilket är en av de mest viktigaste faktorerna för den här typen av Feature Store.
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3

Mandinga, Ailton Mendes dos Santos. "Potencial e viabilidade económica da utilização de estufas para produção de hortaliças em São Tomé e Príncipe." Master's thesis, ISA/UL, 2018. http://hdl.handle.net/10400.5/17809.

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Mestrado em Engenharia Agronómica - Instituto Superior de Agronomia
A sazonalidade na produção de hortaliças em São Tomé e Príncipe é causada principalmente pela presença das chuvas durante oito meses do ano, assim a produção da maioria das hortaliças é muito difícil durante esta época, o que afeta gravemente a disponibilidade, a qualidade e consequentemente a variação do preço destes produtos ao longo do ano. Com o objetivo de verificar o potencial da utilização das estufas como forma de minimizar o problema da sazonalidade, selecionaram-se oito estufas na ilha de São Tomé que foram acompanhadas durante cinco meses, de abril a setembro. Foram também selecionadas as duas hortaliças de maior importância económica e social e que mais são afetadas pela sazonalidade, o tomate (Lycopersicon esculentum) e o pimento (Capsicum annuum). Por conseguinte, acompanhou-se o ciclo cultural e a situação de mercado de forma a comparar potencial e a viabilidade económica das duas culturas dentro e fora da estufa. Começou-se por fazer a caracterização edafoclimática que revelou ser mais favorável para produção de hortaliças ao ar livre durante a época seca (junho a setembro), enquanto que a produção em estufa pode ser feita durante todo o ano, mas durante a época chuvosa (outubro a maio) é mais favorável pelo preço de mercado, sendo muitas vezes a única produção durante os meses de abril e maio. A cultura em estufa, durante a época chuvosa, beneficia dos preços mais elevados que variam entre 55 e 135 nDb kg-1 na cultura do pimento e 22,5 a 47, 5 nDb kg-1 na cultura do tomate. Durante a época seca os preços variam de 37,5 a 65 nDb kg-1 e 12,5 a 20 nDb kg-1 para a cultura do pimento e do tomate, respetivamente. verificou-se que não existe diferenciação de preço entre as hortaliças produzidas dentro e fora das estufas, mas os frutos da estufa possuem uma maior facilidade de venda por apresentarem uma maior qualidade. A produtividade média do tomate e do pimento foram 2,1 kg m-2 e 3,5 kg m-2, respetivamente. Ambas as produtividades são superiores às do ar livre, 1,8 kg m-2 para o tomate e 2,4 kg m-2 para o pimento. A produção total foi de 13 toneladas de pimento e 6 toneladas de tomate em que 62% e 91% respetivamente, foi produzido durante a época de maior escassez, época chuvosa. Assim, pode-se afirmar que, mesmo ainda distante do seu potencial produtivo, as estufas são mais produtivas e estão a contribuir para diminuição da sazonalidade. Por último o custo da estrutura é elevado, 83 USD/m2, com as produtividades atuais torna-se quase impraticável o empréstimo bancário para construção de estufas. Portanto é fundamental que as estufas se aproximem do seu potencial produtivo e para isso propôs-se a introdução de algumas melhorias nas fitotécnicas utilizadas bem como melhorias na gestão das cooperativas
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4

D'Souza, Jude Clement. "KTHFS – A HIGHLY AVAILABLE ANDSCALABLE FILE SYSTEM." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-117918.

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KTHFS is a highly available and scalable file system built from the version 0.24 of the Hadoop Distributed File system. It provides a platform to overcome the limitations of existing distributed file systems. These limitations include scalability of metadata server in terms of memory usage, throughput and its availability. This document describes KTHFS architecture and how it addresses these problems by providing a well coordinated distributed stateless metadata server (or in our case, Namenode) architecture. This is backed with the help of a persistence layer such as NDB cluster. Its primary focus is towards High Availability of the Namenode. It achieves scalability and recovery by persisting the metadata to an NDB cluster. All namenodes are connected to this NDB cluster and hence are aware of the state of the file system at any point in time. In terms of High Availability, KTHFS provides Multi-Namenode architecture. Since these namenodes are stateless and have a consistent view of the metadata, clients can issue requests on any of the namenodes. Hence, if one of these servers goes down, clients can retry its operation on the next available namenode. We next discuss the evaluation of KTHFS in terms of its metadata capacity for medium and large size clusters, throughput and high availability of the Namenode and an analysis of the underlying NDBcluster. Finally, we conclude this document with a few words on the ongoing and future work in KTHFS.
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5

Peinnequin, André. "La nadh : ubiquinone oxydoréductase de la bactérie photosynthétique Rhodobacter capsulatus : étude et caractérisation de 5 gènes (nuo8, nuo10, nuo11, nuo12 et nuo13) homologues aux gènes mitochondriaux nd1, nd6, nd4L, nd5 et nd4." Université Joseph Fourier (Grenoble ; 1971-2015), 1994. http://www.theses.fr/1994GRE10177.

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Recemment, deux genes (nuo8, nuo9) de la bacterie photosynthetique rhodobacter capsulatus, codant des proteines analogues aux sous-unites nd1 et tyky de la nadh:ubiquinone oxydoreductase bovine (complexe l) ont ete clones. Une mini-banque d'adn genomique de la bacterie r. Capsulatus a ete construite dans le vecteur lamdagem-11 pour explorer les regions de l'adn adjacentes aux genes nuo8 et nuo9. Le dechiffrage de la sequence d'un fragment d'adn de 4. 915 pb, localise a portee immediate du gene nuo9, a permis de mettre en evidence 4 genes (nuo10, nuo11, nuo12, nuo13) codant des proteines hydrophobes respectivement analogues aux sous-unites nd6, nd4l, nd5 et nd4 du complexe l mitochondrial. Des souches mutantes de r. Capsulatus ont ete obtenues par insertion d'une cassette de resistance a la kanamycine dans les genes nuo8 et nuo12. Ces mutations retentissent sur le developpement de la bacterie: le developpement aerobie est fortement ralenti, le developpement photoheterotrophique necessite du co#2, les bacteries ne se developpent pas en photoautotrophie. La caracterisation polarographique et biochimique des souches mutantes montre l'absence totale d'activite nadh:ubiquinone oxydoreductase. Les spectres rpe, realises sur les membranes des souches mutantes reduites par le dithionite montrent l'absence des signatures caracteristiques des centres fe-s du complexe l de la bacterie. Ces resultats demontrent que le locus nuo de r. Capsulatus, code pour la nadh:ubiquinone oxydoreductase de la bacterie. La destruction de l'un ou l'autre des genes nuo8 et nuo12 entraine l'absence d'assemblage du complexe l dans la membrane bacterienne. Le retentissement des mutations sur le developpement bacterien est attribue a des perturbations de la balance redox
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6

Ågersten, Alexandra. "Diagnosis of Leber’s hereditary optic neuropathy (LHON) : analysis of MT-ND1, MT-ND4 and MT-ND6 in patients with LHON." Thesis, Uppsala University, Department of Medical Biochemistry and Microbiology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-109492.

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Leber´s hereditary optic neuropathy (LHON), a disease affecting vision, is caused by several point mutations in mitochondrial DNA. Mutations leading to a defect NADH ubiquinone oxidoreductase protein will affect the respiratory chain and cause a disturbed ATP production. It is still unknown why this defect leads to the degeneration of retinal ganglion cells and cells in the opticus nerve as well as demyelination of axons in these areas. Analysis of mitochondrial DNA is an important tool in the diagnosis of the disease. At the present time analysis is based on cleavage by restriction enzymes, which only detects two of the most frequent mutations: m.3460G>A and m.11778G>A. This is far too few considering that more than 30 mutations are known to be associated with LHON. Therefore a new analysis method is requested. Here we describe a method based on the sequencing of the mitochondrial genes MT-ND1, MT-ND4 and MT-ND6, which will detect more than 15 different point mutations associated with the disease. To validate the analysis, DNA from 31 patients with LHON symptoms were sequenced; of these 10 were found to be positive for a LHON mutation. This result indicates that the sequencing analysis will be more effective in diagnosis of LHON than restriction enzymes.


Lebers hereditära optikus neuropati (LHON) är en sjukdom som beror på genetiska förändringar i arvsmassan som leder till att cellens energiomsättning rubbas. Detta gör att nervceller i ögat och synnerven bryts ned vilket leder till en synnedsättning. En patient som drabbas av LHON har inga symptom fram till dess att synen börjar försämras. Sjukdomsförloppet går snabbt och på bara några veckor är patienten ofta helt blind. Diagnostik av LHON idag utgörs av flera undersökningar av öga och synfält. Diagnosen bekräftas av en analys av arvsmassan som finns i mitokondrien, cellens energifabrik. Här beskriver vi en ny förbättrad analysmetod baserad på DNA sekvensering, dvs. bestämning av baserna i mitokondriella arvsmassan. För att utvärdera analysen har vi undersökt 31 patienter med misstänkt LHON - av dessa visade sig 10 bära på en sjuklig förändring. Resultatet visar att sekvensering med fördel kan ersätta den tidigare analysmetoden då fler sjukliga förändringar kan påvisas och utförandet av analysen är mer användarvänligt.

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7

Roy, Poorna Roy. "Analyzing and classifying bimolecular interactions:I. Effects of metal binding on an iron-sulfur cluster scaffold proteinII. Automatic annotation of RNA-protein interactions for NDB." Bowling Green State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1496412736120654.

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8

Bandúr, Juraj. "Návrh a zpracování výukových postupů přístrojové navigace." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231639.

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The diploma thesis deals with concepts of various key tasks for flights operated by device navigation, while these tasks are designed under the requirements of the regulation JAR-FCL 1. The work also includes explanation of the principles of operation of selected radio navigation devices, which are demonstrated in various roles, making these tasks serve well as a possible teaching material for navigation subjects. Part of the work also includes the evaluation of the simulator FlitePro for the purposes of its certification as a training device.
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9

Asif, Muhammad Haseeb. "FlinkNDB : Guaranteed Data Streaming Using External State." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-291361.

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Apache Flink is a stream processing framework that provides a unified state management mechanism which, at its core, treats stream processing as a sequence of distributed transactions. Flink handles failures, re-scaling and reconfiguration seamlessly via a form of a two-phase commit protocol that periodically commits all past side effects consistently into the state backends. This involves invoking and combining checkpoints and, in time of need, redistributing the state to resume data pipelines. All the existing Flink state backend implementations, such as RocksDB, are embedded and coupled with the compute nodes. Therefore, recovery time is proportional to the state needed to be reconfigured and that can take from a few seconds to hours. If application logic is compute-heavy and Flink’s tasks are overloaded, scaling out compute pipeline means scaling out storage together with compute tasks and vice-versa because of the embedded state backends. It also introduces delays due to expensive state re-shuffle and moving large state on the wire. This thesis work proposes the decoupling of the state storage from compute to improve Flink’s scalability. It introduces the design and implementation of a new State backend, FlinkNDB, that decouples state storage from compute. Furthermore, we designed and implemented new techniques to perform snapshotting, and failure recovery to reduce the recovery time close to zero.
Apache Flink är ett strömbehandlingsramverk som tillhandahåller en enhetlig tillståndshanteringsmekanism som i sin kärna behandlar strömbehandling som en sekvens av distribuerade transaktioner. Flink hanterar fel, omskalning och omkonfigurering sömlöst via en form av ett tvåfas-engagemangsprotokoll som regelbundet begår alla tidigare biverkningar konsekvent i tillståndets backends. Detta innebär att man åberopar och kombinerar kontrollpunkter och vid behov omdistribuerar dess tillstånd för att återuppta dataledningar. Alla befintliga backendimplementeringar för Flink-tillstånd, som Rocks- DB, är inbäddade och kopplade till beräkningsnoderna. Därför är återhämtningstiden proportionell mot det tillstånd som behöver konfigureras om och det kan ta från några sekunder till timmar. Om applikationslogiken är beräkningstung och Flinks uppgifter är överbelastade, innebär utskalning av beräkningsrörledning att utskalning av lagring, tillsammans med beräkningsuppgifter och vice versa på grund av det inbäddade tillståndet i backend. Det introducerar också förseningar i förhållande till dyra tillståndsförflyttningar och flyttning av stora datamängder som upptar stora delar av bandbredden. Detta avhandlingsarbete föreslår frikoppling av tillståndslagring från beräkning för att förbättra Flinks skalbarhet. Den introducerar designen och implementeringen av ett nytt tillstånd i backend, FlinkNDB, som frikopplar tillståndslagring från beräkning. Avslutningsvis designade och implementerade vi nya tekniker för att utföra snapshotting och felåterställning för att minska återhämtningstiden till nära noll.
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Sree, Kumar Sruthi. "External Streaming State Abstractions and Benchmarking." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-291338.

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Distributed data stream processing is a popular research area and is one of the promising paradigms for faster and efficient data management. Application state is a first-class citizen in nearly every stream processing system. Nowadays, stream processing is, by definition, stateful. For a stream processing application, the state is backing operations such as aggregations, joins, and windows. Apache Flink is one of the most accepted and widely used stream processing systems in the industry. One of the main reasons engineers choose Apache Flink to write and deploy continuous applications is its unique combination of flexibility and scalability for stateful programmability, and the firm guarantee that the system ensures. Apache Flink’s guarantees always make its states correct and consistent even when nodes fail or when the number of tasks changes. Flink state can scale up to its compute node’s hard disk boundaries using embedded databases to store and retrieve data. Nevertheless, in all existing state backends officially supported by Flink, the state is always available locally to compute tasks. Even though this makes deployment more convenient, it creates other challenges such as non-trivial state reconfiguration and failure recovery. At the same time, compute, and state are bound to be tightly coupled. This strategy also leads to over-provisioning and is counterintuitive on state intensive only workloads or compute-intensive only workloads. This thesis investigates an alternative state backend architecture, FlinkNDB, which can tackle these challenges. FlinkNDB decouples state and computes by using a distributed database to store the state. The thesis covers the challenges of existing state backends and design choices and the new state backend implementation. We have evaluated the implementation of FlinkNDB against existing state backends offered by Apache Flink.
Distribuerad dataströmsbehandling är ett populärt forskningsområde och är ett av de lovande paradigmen för snabbare och effektivare datahantering. Applicationstate är en förstklassig medborgare i nästan alla strömbehandlingssystem. Numera är strömbearbetning per definition statlig. För en strömbehandlingsapplikation backar staten operationer som aggregeringar, sammanfogningar och windows. Apache Flink är ett av de mest accepterade och mest använda strömbehandlingssystemen i branschen. En av de främsta anledningarna till att ingenjörer väljer ApacheFlink för att skriva och distribuera kontinuerliga applikationer är dess unika kombination av flexibilitet och skalbarhet för statlig programmerbarhet, och företaget garanterar att systemet säkerställer. Apache Flinks garantier gör alltid dess tillstånd korrekt och konsekvent även när noder misslyckas eller när antalet uppgifter ändras. Flink-tillstånd kan skala upp till dess beräkningsnods hårddiskgränser genom att använda inbäddade databaser för att lagra och hämta data. I allmänna tillståndsstöd som officiellt stöds av Flink är staten dock alltid tillgänglig lokalt för att beräkna uppgifter. Även om detta gör installationen bekvämare, skapar det andra utmaningar som icke-trivial tillståndskonfiguration och felåterställning. Samtidigt måste beräkning och tillstånd vara tätt kopplade. Den här strategin leder också till överanvändning och är kontraintuitiv för statligt intensiva endast arbetsbelastningar eller beräkningsintensiva endast arbetsbelastningar. Denna avhandling undersöker en alternativ statsbackendarkitektur, FlinkNDB, som kan hantera dessa utmaningar. FlinkNDB frikopplar tillstånd och beräknar med hjälp av en distribuerad databas för att lagra tillståndet. Avhandlingen täcker utmaningarna med befintliga statliga backends och designval och den nya implementeringen av statebackend. Vi har utvärderat genomförandet av FlinkNDBagainst befintliga statliga backends som erbjuds av Apache Flink.
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FERNANDES, Lorena Duarte. "Análise de alterações moleculares nos genes ND1 e ND3 em câncer de pulmão não pequenas células na população paraense." Universidade Federal do Pará, 2018. http://repositorio.ufpa.br/jspui/handle/2011/9904.

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CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico
O carcinoma broncopulmonar é o mais frequente em todo o mundo, sendo uma das neoplasias mais agressivas, possuindo uma razão mortalidade/incidência em torno de 90%, com sobrevida global em cinco anos baixa, cerca de 10 a 15%, na maioria das populações do mundo. Na Região Norte do Brasil, esta patologia é a terceira mais frequente entre os homens e a quarta entre as mulheres. Do ponto de vista anatomopatológico, o câncer de pulmão é classificado em dois tipos principais: pequenas células e não-pequenas células, sendo este último o mais incidente, respondendo por 75% dos casos. Atualmente, a distinção entre os subtipos se baseia em diferenças histológicas, imunohistoquímicas e moleculares. Nesse contexto, é importante ressaltar que as informações moleculares influenciam não só no diagnóstico, prognóstico, mas também na conduta terapêutica. Diversas alterações genéticas e epigenéticas do genoma nuclear estão relacionadas a patogênese deste tumor. Entretanto, alterações na fosforilação oxidativa resultantes da disfunção mitocondrial tem sido há muito tempo sugeridas como envolvidas no processo de tumorigênese. Dessa forma, o presente estudo analisou dois genes do DNA mitocondrial (ND1 e ND3) integrantes do complexo I da cadeia respiratória mitocondrial em 66 amostras de tecido pulmonar de pacientes com e sem câncer de pulmão não pequenas células na população do estado do Pará. Após a análise pelo sequenciamento, foram identificadas quatro alterações no gene ND1: C3553T, T3552A, C3595ins e G3666A e apenas duas alterações no gene ND3: A10398G e C10400T. Dentre as alterações encontradas no gene ND1, não foram observadas significância estatística em relação ao desenvolvimento do câncer de pulmão. Entretanto, foi descoberto uma alteração estrutural no gene ND1 na presença de C3595ins, ainda não descrita na literatura. Ao passo que, a presença do alelo A, observada em T3552A no gene ND1, foi associada de forma significativa ao um efeito protetor ao desenvolvimento de câncer de pulmão. Já alterações no gene ND3 (G10398A e T10400C) foram significantemente associadas com o câncer de pulmão, sendo estas alterações em ND3 potenciais para utilização como marcadores em pacientes com câncer de pulmão não pequenas células.
Bronchopulmonary carcinoma is the most frequent in the world, being one of the most aggressive neoplasms, with a mortality / incidence ratio of around 90%, with overall survival in five years low, about 10 to 15%, in most populations of the world. In the Northern Region of Brazil, this pathology is the third most frequent among men and the fourth among women. From the anatomopathological point of view, lung cancer is classified into two main types: small cells and non-small cells, the latter being the most incident, accounting for 75% of cases. Currently, the distinction between subtypes is based on histological, immunohistochemical, and molecular differences. In this context, it is important to emphasize that molecular information influences not only diagnosis, prognosis, but also therapeutic behavior. Several genetic and epigenetic alterations of the nuclear genome are related to the pathogenesis of this tumor. However, changes in oxidative phosphorylation resulting from mitochondrial dysfunction have long been suggested as involved in the process of tumorigenesis. Thus, the present study analyzed two mitochondrial DNA (ND1 and ND3) genes belonging to the I complex of the mitochondrial respiratory chain in 66 lung tissue samples from patients with and without non-small cell lung cancer in the population of the state of Pará. the sequencing analysis identified four alterations in the ND1 gene: C3553T, T3552A, C3595ins and G3666A and only two changes in the ND3 gene: A10398G and C10400T. Among the alterations found in the ND1 gene, no statistical significance was observed in relation to the development of lung cancer. However, a structural alteration in the ND1 gene was found in the presence of C3595ins, not yet described in the literature. Whereas, the presence of the A allele, observed in T3552A in the ND1 gene, was significantly associated with a protective effect on the development of lung cancer. Already changes in the ND3 gene (G10398A and T10400C) were significantly associated with lung cancer, these changes in ND3 being potential for use as markers in patients with non-small cell lung cancer
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Roncato, Juliana Foletto Fredo. "Estudo associativo entre polimorfismos nos genes ND2 e ND3 que codificam para subunidades da NADH desidrogenase em DNA mitocondrial de pacientes esquizofrênicos." Pontifícia Universidade Católica do Rio Grande do Sul, 2007. http://hdl.handle.net/10923/1373.

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A esquizofrenia é uma doença neuropsiquiátrica que afeta cerca de 1% da população mundial e que, devido aos seus diversos sintomas, acarreta um enorme custo social direto (hospitalizações, atendimentos, medicações) e indireto (improdutividade, repercussões familiares). Os estudos de genética populacional indicam que a esquizofrenia tenha um componente genético relevante além da influência do ambiente. Neste sentido, além de estudos no DNA nuclear, têm sido investigadas as alterações no DNA Mitocondrial (mtDNA). O mtDNA apresenta herança materna, e por isso é muito útil em estudos populacionais. Estudos com doenças neurodegenerativas como a doença de Parkinson e a doença de Alzheimer sugerem que, ao menos em parte, o mtDNA contribua para suas etiologias. Manifestações neuropsiquiátricas características de encefalopatias mitocondriais causadas por mutações do mtDNA são convulsões, demência e dor de cabeça. Além disso, um estado confusional agudo, com alguns sintomas semelhantes aos que ocorrem na esquizofrenia (desorganização mental e alucinações), às vezes é observado em MELAS (mitochondrial encephalomyopathy, lactic acidosis, stroke-like episodes), uma encefalopatia mitocondrial típica. Dessa forma, o objetivo dessa pesquisa foi averiguar uma possível associação entre polimorfismos A4769G e A10398G de mtDNA, que já foram descritos como predisponentes a outras doenças neuropsiquiátricas, com o desenvolvimento da esquizofrenia. Os polimorfismos A4769G e A10398G estão respectivamente localizados nos genes ND2 e ND3, que codificam para subunidades 2 e 3 da NADH Desidrogenase. Para relacionar esses polimorfismos com a esquizofrenia, testamos 76 pacientes esquizofrênicos quanto à ocorrência ou não destas variantes polimórficas no mtDNA e comparamos com as amostras de 88 controles sadios. Esses polimorfismos foram analisados utilizado-se o seqüenciador automático de DNA “MegaBACE” 1000 (GE Healthcare™) do Centro de Biologia Genômica e Molecular da PUCRS. Os cromatogramas gerados pela corrida eletroforética das reações de seqüenciamento foram analisadas no programa Chromas para determinar a ocorrência ou não da variação polimórfica. Quanto à análise estatística, foi realizado teste do qui-quadrado para variáveis categóricas. O nível de significância estatística foi p ≤ 0,05.Em relação ao polimorfismo A4769G, foram analisadas amostras de 76 pacientes dos quais 61 (80,3%) apresentaram o alelo G e 15 (19,7%) apresentaram o alelo A nesta posição. Das 88 amostras de controles analisadas, obtivemos 82 (93,2%) com o alelo G e 6 (6,8%) com o alelo A (Qui-quadrado p=0,014, Odds ratio=2. 895). Em relação ao polimorfismo A10398G, dos 62 pacientes analisados, 17 (27,4%) apresentaram o alelo G e 45 (72,6%) o alelo A. Dos 76 controles, 34 (44,7%) apresentaram a presença do alelo mutante G e 42 (55,3%) apresentaram o alelo A para esta posição (Qui-quadrado p=0,036, Odds ratio=1. 313). O estudo mostra diferenças estatisticamente significativas na freqüência dos sistemas polimórficos estudados entre pacientes esquizofrênicos e controles. Estudos adicionais são necessários para avaliar sua relevância do ponto de vista funcional.
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Roncato, Juliana Foletto Fredo. "Estudo associativo entre polimorfismos nos genes ND2 e ND3 que codificam para subunidades da NADH desidrogenase em DNA mitocondrial de pacientes esquizofr?nicos." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2007. http://tede2.pucrs.br/tede2/handle/tede/5471.

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A esquizofrenia ? uma doen?a neuropsiqui?trica que afeta cerca de 1% da popula??o mundial e que, devido aos seus diversos sintomas, acarreta um enorme custo social direto (hospitaliza??es, atendimentos, medica??es) e indireto (improdutividade, repercuss?es familiares). Os estudos de gen?tica populacional indicam que a esquizofrenia tenha um componente gen?tico relevante al?m da influ?ncia do ambiente. Neste sentido, al?m de estudos no DNA nuclear, t?m sido investigadas as altera??es no DNA Mitocondrial (mtDNA). O mtDNA apresenta heran?a materna, e por isso ? muito ?til em estudos populacionais. Estudos com doen?as neurodegenerativas como a doen?a de Parkinson e a doen?a de Alzheimer sugerem que, ao menos em parte, o mtDNA contribua para suas etiologias. Manifesta??es neuropsiqui?tricas caracter?sticas de encefalopatias mitocondriais causadas por muta??es do mtDNA s?o convuls?es, dem?ncia e dor de cabe?a. Al?m disso, um estado confusional agudo, com alguns sintomas semelhantes aos que ocorrem na esquizofrenia (desorganiza??o mental e alucina??es), ?s vezes ? observado em MELAS (mitochondrial encephalomyopathy, lactic acidosis, stroke-like episodes), uma encefalopatia mitocondrial t?pica. Dessa forma, o objetivo dessa pesquisa foi averiguar uma poss?vel associa??o entre polimorfismos A4769G e A10398G de mtDNA, que j? foram descritos como predisponentes a outras doen?as neuropsiqui?tricas, com o desenvolvimento da esquizofrenia. Os polimorfismos A4769G e A10398G est?o respectivamente localizados nos genes ND2 e ND3, que codificam para subunidades 2 e 3 da NADH Desidrogenase. Para relacionar esses polimorfismos com a esquizofrenia, testamos 76 pacientes esquizofr?nicos quanto ? ocorr?ncia ou n?o destas variantes polim?rficas no mtDNA e comparamos com as amostras de 88 controles sadios. Esses polimorfismos foram analisados utilizado-se o seq?enciador autom?tico de DNA MegaBACE 1000 (GE Healthcare ) do Centro de Biologia Gen?mica e Molecular da PUCRS. Os cromatogramas gerados pela corrida eletrofor?tica das rea??es de seq?enciamento foram analisadas no programa Chromas para determinar a ocorr?ncia ou n?o da varia??o polim?rfica. Quanto ? an?lise estat?stica, foi realizado teste do qui-quadrado para vari?veis categ?ricas. O n?vel de signific?ncia estat?stica foi p ≤ 0,05. Em rela??o ao polimorfismo A4769G, foram analisadas amostras de 76 pacientes dos quais 61 (80,3%) apresentaram o alelo G e 15 (19,7%) apresentaram o alelo A nesta posi??o. Das 88 amostras de controles analisadas, obtivemos 82 (93,2%) com o alelo G e 6 (6,8%) com o alelo A (Qui-quadrado p=0,014, Odds ratio=2.895). Em rela??o ao polimorfismo A10398G, dos 62 pacientes analisados, 17 (27,4%) apresentaram o alelo G e 45 (72,6%) o alelo A. Dos 76 controles, 34 (44,7%) apresentaram a presen?a do alelo mutante G e 42 (55,3%) apresentaram o alelo A para esta posi??o (Qui-quadrado p=0,036, Odds ratio=1.313). O estudo mostra diferen?as estatisticamente significativas na freq??ncia dos sistemas polim?rficos estudados entre pacientes esquizofr?nicos e controles. Estudos adicionais s?o necess?rios para avaliar sua relev?ncia do ponto de vista funcional.
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14

Pätsi, J. (Jukka). "Catalytic core of respiratory chain NADH-ubiquinone oxidoreductase:roles of the ND1, ND6 and ND4L subunits and mitochondrial disease modelling in Escherichia coli." Doctoral thesis, Oulun yliopisto, 2011. http://urn.fi/urn:isbn:9789514294723.

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Abstract NADH-ubiquinone oxidoreductase (complex I) is one of the largest enzymes in mammals. Seven (ND1-ND6 and ND4L) of its 45 subunits are encoded in mitochondrial DNA, mutations of which are usually behind mitochondrial diseases such as Leber hereditary optic neuropathy (LHON) and MELAS-syndrome. The rest of the genes are located in the nucleus. Bacterial homologs of complex I (NDH-1) consist of only 13–14 subunits, comprising the catalytic core of the enzyme. These complexes are simpler but perform a similar function. Escherichia coli NDH-1 was employed here to generate amino acid replacements at conserved sites in NuoH, NuoJ and NuoK, counterparts of ND1, ND6 and ND4L, to elucidate their role in complex I. Consequences of homologous amino acid substitutions brought about by ND1-affecting LHON/MELAS-overlap syndrome-associated m.3376G>A and m.3865A>G mutations and the ND6-affecting m.14498T>C substitution associated with LHON were also studied to validate their pathogenicity. Effects of the site-directed mutations were evaluated on the basis of enzyme activity, inhibitor sensitivity and growth phenotype. Highly conserved glutamate-residues 36 and 72 within transmembrane helices of NuoK in positions similar to proton translocating transmembrane proteins were found essential for electron transfer to ubiquinone and growth on medium necessitating normal proton transfer by NDH-1. NuoH and NuoJ replacements at sites corresponding to targets of m.3376G>A and m.14498T>C decreased ubiquinone reductase activity and altered the ubiquinone binding site, while the counterpart of m.3865A>G was without a major effect. Other NuoH and NuoJ mutations studied also affected the interactions of ubiquinone and inhibitors with NDH-1. The results corroborate the pathogenicity of the m.14498T>C and m.3376G>A mutations and demonstrate that the overlap syndrome-associated modification affects complex I in a pattern which appears to combine the effects of separate mutations responsible for LHON and MELAS. Change in ubiquinone binding affinity is a likely pathomechanism of all LHON-associated mutations. Effects of the NuoH, NuoJ and NuoK subunit substitutions also indicate that ND1 and ND6 subunits contribute to the ubiquinone-interacting site of complex I and the site is located in the vicinity of the membrane surface, while ND4L is likely involved in proton pumping activity of the enzyme
Tiivistelmä 45 alayksiköstä muodostuva NADH-ubikinoni oksidoreduktaasi (kompleksi I) on nisäkkäiden suurimpia entsyymejä. Sen mitokondriaalisessa DNA:ssa koodattujen alayksiköiden ND1-ND6 ja ND4L geeneihin liittyvät mutaatiot ovat yleisiä mitokondriosairauksien, kuten Leberin perinnöllisen näköhermoatrofian (LHON) ja MELAS-oireyhtymän, syitä. Bakteerien vastaava entsyymi (NDH-1) koostuu vain 13–14 alayksiköstä. Tästä huolimatta sen katalysoima reaktio on samankaltainen kuin kompleksi I:n. NDH-1:n katsotaankin edustavan entsyymin katalyyttistä ydintä. Tässä työssä tutkittiin ND1, ND6 ja ND4L alayksiköiden tehtävää kompleksi I:ssä niiden Escherichia coli bakteerissa olevien vastineiden (NuoH, NuoJ ja NuoK) kohdennetun mutageneesin avulla. Samaa lähestymistapaa käytettiin LHON/MELAS-oireyhtymässä todettujen ND1 alayksikön mutaatioiden, m.3376G>A ja m.3865A>G, ja LHON:ssa havaitun ND6:n m.14498T>C mutaation aiheuttamien aminohappomuutosten seurauksien selvittämiseen. Tehtyjen mutaatioiden vaikutuksia arvioitiin entsyymiaktiivisuus-mittauksin ja kasvukokein. NuoK:n solukalvon läpäisevissä rakenteissa olevien kahden glutamaatti-aminohappotähteen sijainti muistuttaa protoneita kalvon läpi kuljettavissa proteiineissa todettua. NuoK:n glutamaattien havaittiinkin olevan tärkeitä elektronien ja protonien kuljetukselle kompleksi I:ssä. m.3376G>A ja m.14498T>C mutaatioiden aiheuttamien aminohappomuutosten vastineet NDH-1:ssä alensivat NDH-1:n elektroninsiirtoaktiivisuutta ja heikensivät ubikinonin sitoutumista, kun taas m.3865A>G mutaatiolla ei ollut vaikutusta. Muut NuoH ja NuoJ alayksiköihin tehdyt aminohappovaihdokset johtivat huonontuneeseen ubikinonin ja kompleksi I:n inhibiittoreiden sitoutumiseen. Saadut tulokset vahvistavat m.3376G>A ja m.14498T>C mutaatioiden patogeenisyyden. Ne myös osoittavat, että LHON/MELAS-oireyhtymään liitetyn mutaation biokemiallisissa vaikutuksissa yhdistyvät sekä LHON:ssa että MELAS-oireyhtymässä todettujen mutaatioiden seuraukset. Esitetyt tulokset tukevat näkemystä siitä, että ubikinonin ja kompleksi I:n välisessä vuorovaikutuksessa tapahtuva muutos on kaikille LHON:aan liitetyille mutaatioille yhteinen vaikutusmekanismi. NuoH:n, NuoJ:n ja NuoK:n kohdennetusta mutageneesista saatujen tulosten perusteella ND1 ja ND6 alayksiköt ovat osa ubikinonin sitoutumispaikkaa entsyymikompleksissa, kun taas ND4L osallistuu protoninkuljetukseen
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15

Flückiger, Vera. "n/a not/available nachfrage und angebot von Standortinformation in der Immobilienbranche : NDK/NDS Nachdiplomarbeit im Rahmen des Nachdiplomstudiums in Raumplanung an der ETH Zürich /." Zürich : ETH Zürich, [Institut für Orts-, Regional- und Landesplanung], 2001. http://e-collection.ethbib.ethz.ch/show?type=dipl&nr=70.

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16

Bělohradová, Eva. "NDC důchodový systém." Master's thesis, Vysoká škola ekonomická v Praze, 2011. http://www.nusl.cz/ntk/nusl-85949.

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My diploma thesis deals with the introduction and analysis of the NDC system (Notional Defined Contribution). I devote myself to pension system in the Czech Republic too. The diploma thesis provides informations on individual elements of the NDC system and its financial sustainability. In the theoretical part I deal with the pension systems in general and with states that have already introduced the NDC system. In the practical part I deal with the pension system of the Czech Republic in according to the questionnaire. I try to evaluate whether the NDC system is advantageous for the Czech Republic.
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17

Guyot, Yannick. "Absorptions dans l'état excité et performances laser des cristaux dopés par l'ion néodyme : Y3Al5O12:Nd3+, YLiF4:Nd3+ et LaMgAl11O19:Nd3+." Lyon 1, 1993. http://www.theses.fr/1993LYO10221.

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Cette these constitue une etude comparative des proprietes spectroscopiques et laser de l'ion neodyme place dans differents types d'environnement des cristaux bien connus de yag, ylf mais aussi dans un materiau plus complexe: lma (systeme multisite). Les proprietes spectroscopiques generales sont d'abord rappelees. Des fluorescences anti-stokes sont alors mises en evidence sous excitation autour de 800 nm, longueur d'onde des diodes laser devant servir au pompage dans les systemes miniaturises. Ce phenomene est explique par des mecanismes de transfert d'energie entre les ions nd mais aussi par le processus d'absorption dans l'etat excite (aee). Une part importante de ce travail est donc consacree a l'etude quantitative directe des phenomenes d'aee tant dans le domaine d'emission laser infrarouge situe vers 1060 nm et 1032 nm que dans le domaine correspondant au pompage visible par lampe flash dans les systemes laser de forte puissance. Une analyse theorique commune tant des proprietes spectroscopiques generales que des phenomenes d'aee est mise en uvre grace au formalisme de judd-ofelt. Un developpement theorique montre d'autre part, le peu d'influence de l'aee dans le domaine de pompage sur les performances laser, alors que du point de vue thermique il en est autrement. Enfin, l'influence de l'elargissement inhomogene des raies optiques permet d'expliquer le comportement particulier de l'efficacite laser dans le lma:nd
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18

Breßler, Julia, and Evelina Koch. "Expansionslernprojekt Nachhaltigkeitsbeauftragter (ELP NHB)." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-212943.

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Veränderungen sind in Lebens- und Arbeitskontexten allgegenwärtig. Sie führen zum Durchbrechen von routinierten Pfaden und Auflösen von Rezeptwissen. Darüber hinaus generieren sie Unsicherheit, Komplexität und Widersprüchlichkeit. Studierenden diese Phänomene zu vergegenwärtigen bzw. sie für diese zu sensibilisieren ist ebenso eine Herausforderung der Hochschuldidaktik. Des Weiteren sieht sich die Hochschule des 21. Jahrhunderts mit der Bildung für nachhaltige Entwicklung konfrontiert. Im Rahmen des Lehr-Lern-Projekts haben wir uns dieser Schwerpunkte angenommen. Der Werkstattbericht verdeutlicht die Generierung einer expansiven Bildungskonzeption und versucht einen Möglichkeitsraum für die Hochschuldidaktik zu schaffen. Des Weiteren stellen wir die Evaluation sowie Implikationen für eine Weiterentwicklung des didaktischen Konzepts dar.
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19

Westerfield, Anne Laura. "Naval doctrine : an analysis of the effectiveness of NDP 1 and NDP 6 /." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1996. http://handle.dtic.mil/100.2/ADA313496.

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Thesis (M.S. in System Technology (Command, Control, and Communications)) Naval Postgraduate School, June 1996.
"June 1996." Thesis advisor(s): W.P. Hughes, W. G. Kemple. Bibliography: p. 49-53. Also Available online.
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20

Batalioto, Fernando. "Caracterização espectroscópica de vidros fluoroindogalato dopados com Nd3+ e com Nd3+ e Yb3+." Universidade de São Paulo, 2000. http://www.teses.usp.br/teses/disponiveis/76/76131/tde-07022014-084315/.

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O presente trabalho consiste em uma caracterização ótica de vidros fluoretos dopados com Nd3+ e com Yb3+ dando ênfase ao estudo dos processos de transferência de energia entre estes íons. Também são abordadas possíveis aplicações que os referidos vidros dopados com Nd3+ e codopados com Nd3+ e Yb3+ possam encontrar. Algumas destas aplicações são em meio ativo para laseres no infravermelho e em células solares. Para tal caracterização foram realizadas medidas de absorção, de tempo de vida, de luminescência no infravermelho e no visível e de luminescência resolvida no tempo. Também encontram-se neste trabalho cálculos sobre as probabilidades de transição radiativa dos níveis 4F3/2 do Nd3+ e 2F5/2 do Yb3+ além de um estudo sobre os processos de transferência de energia entre estes íons. Das medidas mencionadas acima foi encontrado que a concentração de neodímio para a qual se observa a emissão mais intensa é de ≅ 1,5% mol Nd F3 e que a eficiência quântica de emissão do nível 4F3/2 deste íon, no vidro fluoroindogalato, é alta (0,96). Nas amostras codopadas com Nd3+ e Yb3+ o máximo da emissão ocorre para a amostra com 1% NdF3 e 2% YbF3. Sobre os processos de transferência de energia, os parâmetros que caracterizam a transferência entre os íons Nd3+ e entre Nd3+ e Yb3+, foram calculados pelo modelo de Dexter e obtidos experimentalmente através das curvas de decaimento da luminescência. Os valores conseguidos das duas maneiras estão em boa concordância entre si
The present work consists in an optical characterization of Nd3+ doped and Nd3+ and Yb3+ codoped fluoride glasses with emphasis on the study of energy transfer processes among these ions. Possible applications that the refered Nd3+ doped and Nd3+ and Yb3+ codoped glasses can find are also considered. Some of these applications are as active media of infrared lasers and in solar cells. The characterization was done by absorption, lifetime, infrared and visible luminescence and time resolved measurements. In this work some calculations of the radioactive transition probabilities of the 4F3/2 do Nd3+ e 2F5/2 of Yb3+ levels and a study of the energy transfer processes among these ions were also carried out. From the above mentioned measurements it was found that the concentration at which the neodymium emission is higher is about 1,5% mol NdF3 and that the quantum efficiency of the emission for the 4F3/2 do Nd3+ of Nd3+ level, in fluoroindogallate, is high (0.96). In the Nd3+ and Yb3+ codoped samples the maximum emission is observed for the sample with 1% Nd3+ and 2% Yb F3. Considering the energy transfer processes, the parameter that characterizes the energy transfer among Nd3+ ions and among Nd3+ and Yb3+ was calculated by Dexter\'s model and experimentally obtained from the decay curve of the luminescence intensity. The values found are in good agreement to each other
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Boroujerdi, A. [Verfasser]. "Phasengleichgewichte in den Systemen UO₂-UO₃-NdO₁,₅ und NpO(2+x)-NdO₁,₅ / A. Boroujerdi." Karlsruhe : KIT-Bibliothek, 2009. http://d-nb.info/1186905646/34.

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22

Gros, X. E. "Fusion of multiprobe NDT data." Thesis, Robert Gordon University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294936.

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23

Meyendorf, N., M. Oppermann, P. Krueger, M. Roellig, and K. J. Wolter. "NDE applications in microelectronic industries." SPIE, 2016. https://tud.qucosa.de/id/qucosa%3A35100.

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New concepts in assembly technology boost our daily life in an unknown way. High end semiconductor industry today deals with functional structures down to a few nanometers. ITRS roadmap predicts an ongoing decrease of the “DRAM half pitch” over the next decade. Packaging of course is not intended to realize pitches at the nanometer scale, but has to face the challenges of integrating such semiconductor devices with smallest pitch and high pin counts into systems. Advanced techniques of nondestructive evaluation (NDE) with resolutions in volume better than 1 micrometer vixen size are urgently needed for the safety and reliability of electronic systems, especially those that are used in long living applications. The development speed of integrated circuits is still very high and is not expected to decrease in the next future. The integration density of microelectronic devices is increasing, the dimensions become smaller and the number of I/O's is getting higher. The development of new types of packages must be done with respect to reliability issues. Potential damage sources must be identified and finally avoided in the new packages. In power electronics production the condition monitoring receives a lot of interest to avoid electrical shortcuts, dead solder joints and interface crac king. It is also desired to detect and characterize very small defects like transportation phenomenon or Kirkendall voids. For this purpose, imaging technologies with resolutions in the sub-micron range are required.
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24

MacLeod, Charles Norman. "Considerations for automated NDE applications." Thesis, University of Strathclyde, 2014. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=24395.

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To ensure that infrastructure owners, operators and planners have sufficient information readily available to them regarding the state and condition of their asset, numerous advances and developments have been demonstrated in the field of Non Destructive Evaluation (NDE). The process of detailed imaging and examination of structures and components in a sensitive, safe and inherently non-intrusive manner has numerous advantages in operational, financial and safety terms. Only by delivering NDE sensors directly to all points of interest on a structure, can the desired coverage of the structure or component be undertaken. This vision has driven research and developments in the area of automated collection of NDE data. This thesis identifies and addresses key challenges and technical boundaries currently preventing wider industrial uptake of automated NDE. This has been accomplished through novel research and developments in key areas related to platform kinematics and dynamics, localisation and registration to the structure under inspection, path planning and physical NDE sensing. These advances provide a unified framework to both establish and progress remote automated NDE forward for future commercial deployment. A contribution to knowledge was presented on the positional performance characteristics of a custom rotary wing aerial inspection platform after a series of hover tests within a tracking volume. An additional contribution was presented on the results of a comprehensive evaluation of a laser based positioning sensor operating under a wide range of engineering materials, along with the development of a novel distance correction algorithm. A new custom approach for robotic NDE path planning was researched and developed based on conventional CAD/CAM machining, while utilising a novel custom agile ultrasonic thickness mapping crawler to highlight proof of principle. Both of these approaches provide an additional contribution to knowledge, both individually in their respective fields and also together in highlighting the unique advantages of their combined approach. Finally a new NDE sensor concept based on the vibrissae of rodents such as rats and mice, for both surface roughness and surface profiling measurement, was adapted and investigated for NDE sensing applications. The results document a contribution to knowledge in the area with discrimination down to 14 micrometre Roughness Average presented.
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25

Morsakov, Wladimir. "Elektroresistiver Effekt im sauerstoffdefizitären Manganit Nd2/3Sr1/3MnO3-d [Nd2/3 Sr1/3 Mno3-delta]." [S.l.] : [s.n.], 2006. http://webdoc.sub.gwdg.de/diss/2006/morsakov.

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26

Shrestha, Survesh Bahadur. "Defect Detection on Rail Base Area Using Infrared Thermography." OpenSIUC, 2020. https://opensiuc.lib.siu.edu/theses/2758.

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This research aims to investigate the application of infrared thermography (IRT) as a method of nondestructive evaluation (NDE) for the detection of defects in the rail base area. Rails have to withstand harsh conditions during their application. Therefore, defects can develop in the base area of rails due to stresses such as bending, shear, contact, and thermal stresses, fatigue, and corrosion. Such defects can cause catastrophic failures in the rails, ultimately leading to train derailments. Rail base defects due to fatigue and corrosion are difficult to detect and currently there are no reliable or practical non-destructive evaluation (NDE) methods for finding these types of defects in the revenue service. Transportation Technology Center, Inc. (TTCI) had previously conducted a research on the capability of flash IRT to detect defects in rail base area based on simulation approach. The research covered in this thesis is the continuation of the same project.In this research, three rail samples were prepared with each containing a notched-edge, side-drilled holes (SDHs), and bottom-drilled holes (BDHs). Two steel sample blocks containing BDHs and SDHs of different sizes and depths were also prepared. Preliminary IRT trials were conducted on the steel samples to obtain an optimal IRT setup configuration. The initial inspections for one of the steel samples were outsourced to Thermal Wave Imaging (TWI) where they employed Thermographic Signal Reconstruction (TSR) technique to enhance the resulting images. Additional inspections of the steel samples were performed in the Southern Illinois University-Carbondale (SIUC) facility. In case of the rail samples, the SDHs and the notched-edge reflectors could not be detected in any of the experimental trials performed in this research. In addition, two more rail samples containing BDHs were prepared to investigate the detection capabilities for three different surface conditions: painted, unpainted, and rusted. The painted surface provided a best-case scenario for inspections while the other conditions offered further insight on correlating the application to industry-like cases.A 1300 W halogen lamp was employed as the heat source for providing continuous thermal excitation for various durations. Post-processing and analysis of the resulting thermal images was performed within the acquisition software using built-in analysis tools such as temperature probes, Region of Interest (ROI) based intensity profiles, and smoothing filters. The minimum defect diameter to depth (aspect) ratio detected in preliminary trials for the steel sample blocks were 1.0 at a diameter of 4.7625 mm (0.1875 in) and 1.5 at a diameter of 3.175 mm (0.125 in). For the inspection of painted rail sample, the longest exposure times (10 sec) provided the best detection capabilities in all sets of trials. The three holes having aspect ratio greater or equal to 1.0 were indicated in the thermal response of the painted and rusted samples while only the two holes having aspect ratio greater or equal to 1.5 were indicated in the unaltered sample. Indications of reflectors were identified through qualitative graphical analysis of pixel intensity distributions obtained along a bending line profile. The results obtained from the painted sample provided a baseline for analyzing the results from the unpainted and rusted rail samples. This provided an insight on the limitations and requirements for future development. The primary takeaway is the need for an optimized heat source. Poor contrast in the resulting image for the unpainted and rusted rail samples is experienced due to both noise and lack of penetration of the heat energy. This could have been due to decreased emissivity values. Moreover, the excitation method employed in this research does not comply with current industry standards for track clearances. Therefore, exploration of alternative excitation methods is recommended.
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Fabri, Angélica da Conceição Oliveira Coelho. "Análise comparativa da reatividade anti-LID-1, NDO-LID, NDO-HSA e PGL-1 em hanseníase." Universidade Federal de Minas Gerais (UFMG), 2015. https://repositorio.ufjf.br/jspui/handle/ufjf/7027.

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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.
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28

Ho, Kwok Shun. "Advances in EMAT measurements for NDE." Thesis, University of Warwick, 2007. http://wrap.warwick.ac.uk/67107/.

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This thesis describes a variety of experiments, many using advanced signal processing techniques, and electromagnetic acoustic transducers (EMATs). The first sections of this thesis describe the application of the pulse-compression signal processing technique with EMATs. This has been shown to improve the signal-to-noise ratio without the use of high levels of signal averaging, and thus potentially increases the speed of measurements. Ultrasonics thickness measurements and imaging were carried out to show that pulse-compression can be applied to the testing of the metals. The work was extended to demonstrate the successful measurement of fill level in drinks cans, and the detection of foreign bodies using fan-beam tomographic imaging in the drink cans. This thesis also describes the application of a continuous wavelet transform (CWT) to EMATs. The technique was applied to experimental EMAT data in thin metal plates, to identify propagation of s0, a0, a1, S1 and S2 modes in an aluminium plate from one waveform. To illustrate the usefulness of the approach, the extracted multiple modes were applied to tomographic reconstructions of artificial defects in plates. This thesis also describes metal texture measurements using EMATs and wavelet processing. The work described in this section focuses on the multi-scale discrete wavelet method where the analysis in time and in wavelet scale is discrete as opposed to the CWT. The use of discrete wavelet processing for signal analysis can improve the performance of EMATs data in highly noisy environments. Another section describes the use of the micro-stereolithography (MSL) process to fabricate EMATs, and this is followed by a description of the Synthetic Aperture Focussing Technique (SAFT) algorithm used to reconstruct images of data obtained from these EMATs. Finally, results are given, demonstrating that the EMA Ts can be used to perform NDE inspections. The thesis also contains conclusions and suggestions for further work.
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29

Summan, Rahul. "Positioning for mobile NDE inspection robots." Thesis, University of Strathclyde, 2012. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=20347.

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Ageing infrastructure worldwide requires periodic inspection, often in-situ, in order to ensure continued safe and economic operations as well as adherence to stringent quality and performance requirements. In service automated Nondestructive Evaluation, where feasible, is highly attractive, and potentially allows inspection of operational plant. The use of such technology is very attractive in terms of safety, cost and the potential for minimal disruption to the inspection site especially if plant operations can remain online. Automated Nondestructive Evaluation in the form of remotely operated robotic vehicles is an active area of research. Knowledge of position relative to a frame of reference is a key aspect for a robotic Nondestructive Evaluation system in order to associate sensor measurements with locations on the structure being investigated. This thesis investigates relative and absolute positioning techniques for a single robot. The accuracy and repeatability of a photogra mmetry system is characterised over a large volume using a high accuracy metrology instrument. It was found that the photogrammtery system was most accurate in the centre of the volume and least accurate at the edges. This photogrammetry system is then used to evaluate the performance of algorithms developed in subsequent research. An image based positioning system is implemented which extracts motion information from a camera carried onboard a robot. The system is evaluated on surfaces typically found in industrial environments. Ultrasonic ranging techniques are investigated for robot positioning. In particular a low cost, modular, ultrasonic positioning system is characterised and calibrated. Bayesian filtering in the form of an Extended Kalman and Particle Filter are implemented to fuse noisy optical encoders estimates available at 100 Hz and the ultrasonic positioning measurements available at 3 Hz. The extended Kalman Filter, at lower computational cost, was found to produce the lowest error.
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30

Aubry, Elian. "Protocole de routage pour l’architecture NDN." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0267/document.

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Parmi les architectures orientées contenu, l'architecture NDN (Named-Data Networking) a su agréger la plus importante communauté de chercheurs et est la plus aboutie pour un Internet du futur. Dans le cadre de l'architecture NDN, au cours de ce doctorat, nous nous sommes concentrés sur les mécanismes de routage adaptés à cette nouvelle vision du réseau. En effet, la capacité à acheminer une requête vers la destination est fondamentale pour qu'une architecture réseau soit fonctionnelle et cette problématique avait été très peu étudiée jusqu'alors. Ainsi, dans ce manuscrit, nous proposons le protocole de routage SRSC (SDN-based Routing Scheme for CCN/NDN), qui repose sur l'utilisation du paradigme des réseaux logiciels (Software-Defined Networks\\, SDN). SRSC utilise un contrôleur capable de gérer le plan de contrôle du réseau NDN. En centralisant l'ensemble des informations telles que la topologie du réseau, la localisation des différents contenus et le contenu des mémoires cache des nœuds du réseau, le contrôleur va pouvoir établir la meilleure route pour acheminer les requêtes vers le contenu. SRSC permet également un routage de type anycast, c'est à dire qu'il permet d'acheminer les requêtes vers le nœud le plus proche qui dispose des données, permettant d'optimiser la distribution des requêtes dans le réseau et de répartir la charge parmi tous les nœuds. De plus, SRSC utilise uniquement les messages Interest et Data de l'architecture NDN et tient son originalité du fait qu'il s'affranchit complètement de l'infrastructure TCP/IP existante. Dans un premier temps, SRSC a été évalué via simulation avec le logiciel NS-3 où nous l'avons comparé à la méthode d'inondation des requêtes, appelée flooding, initialement proposée par NDN. SRSC a ensuite été implanté dans NDNx, l'implantation open source de l'architecture NDN, puis déployé sur notre testbed utilisant la technologie Docker. Ce testbed permet de virtualiser des nœuds NDN et d'observer un réel déploiement de cette architecture réseau à large échelle. Nous avons ainsi évalué les performances de notre protocole SRSC sur notre testbed virtualisé et nous l'avons comparé au protocole NLSR, (Named-Data Link State Routing Protocol), le protocole de routage du projet NDN
Internet is a mondial content network and its use grows since several years. Content delivery such as P2P or video streaming generates the main part of the Internet traffic and Named Data Networks (NDN) appear as an appropriate architecture to satisfy the user needs. Named-Data Networking is a novel clean-slate architecture for Future Internet. It has been designed to deliver content at large scale and integrates several features such as in-network caching, security, multi-path. However, the lack of scalable routing scheme is one of the main obstacles that slow down a large deployment of NDN at an Internet-scale. As it relies on content names instead of host address, it cannot reuse the traditional routing scheme on the Internet. In this thesis, we propose to use the Software-Defined Networking (SDN) paradigm to decouple data plane and control plane and present SRSC, a new routing scheme for NDN based on SDN paradigm. Our solution is a clean-slate approach, using only NDN messages and the SDN paradigm. We implemented our solution into the NS-3 simulator and perform extensive simulations of our proposal. SRSC show better performances than the flooding scheme used by default in NDN. We also present a new NDN testbed and the implementation of our protocol SRSC, a Controlled-based Routing Scheme for NDN. We implemented SRSC into NDNx, the NDN implementation, and deployed it into a virtual environment through Docker. Our experiments demonstrate the ability of our proposal to forward Interest, while keeping a low computation time for the Controller and low delay to access Content. Moreover, we propose a solution to easily deploy and evaluate NDN network, and we compare SRSC with NLSR, the current routing protocol used in NDNx
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31

Komárková, Tereza. "NDT kontrola zabudovaných kotev do betonu." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2012. http://www.nusl.cz/ntk/nusl-225571.

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Non-destructive inspection using ultrasonic anchoring method is the only possible way to detect inadequate anchorage length. For rescue roads systems inadequate anchoring can have fatal consequences. Therefore, control anchoring bridge barriers should be carried out every installation of crash barriers.
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32

Andhee, Avinash. "A novel compact Shearographic NDT system." Master's thesis, University of Cape Town, 2005. http://hdl.handle.net/11427/5546.

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Includes bibliographical references
There is a need in industry and the NDT (Non-destructive Testing) community for quick, reliable, user-friendly and cost-effective compact NDT systems that can be used on a wide variety of materials and structures, for quality assurance and maintenance. Designing and building a compact Shearographic NDT system will enhance the capability of inspection during quality assurance and maintenance routines as well as reduce inspection time. Older compact Shearographic systems, which have been tested satisfactorily both under laboratory and field conditions at the NDT Laboratory at the University of Cape Town, have a rather restricted field of view. This is due to the proprietary shearing optics being placed in front of the camera lens, which in other words means that the field of view can only be increased by using a relatively small focal length camera lens which results in having to increase the size of the shearing optics. This would make the compact Shearographic device much larger which is counter-productive since technology enables/directs research and development toward more compact devices.
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Rusovová, Ivana. "Zavedení NDC systému v České republice." Master's thesis, Vysoká škola ekonomická v Praze, 2010. http://www.nusl.cz/ntk/nusl-74732.

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The subject of this thesis is application of Notional Defined Contribution system in Czech Republic. In this pension system everybody has his own individual pension account on which he or she saves money. Interest is accredited to this account. When this person retires, the pension is calculated based on pension account balance. Contributions do not really stay in pension system, but they are paid to current pensioners (resemblance to PAYG system). In first chapter I deal with pension systems in general, in second chapter I deal with theoretical NDC system. In third chapter I analyze practical application of NDC system in Sweden. Fourth part of this thesis analyses the possibility of introducing NDC pension system in Czech republic.
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Pavlakovic, Brian Nicholas. "Leaky guided ultrasonic waves in NDT." Thesis, Imperial College London, 1998. http://hdl.handle.net/10044/1/7907.

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35

Welter, John T. "Oblique angle pulse-echo ultrasound characterization of barely visible impact damage in polymer matrix composites." University of Dayton / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1575295152635788.

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36

Olsson, Johan. "Managing clearinghouse risk for NDF cleared contracts : Validating the HS/VaR method for NDF FX CCP Clearing risk." Thesis, KTH, Matematisk statistik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-168635.

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In this thesis we describe and discuss the reality for a central clearing party clearinghouse. The importance of sound risk management is discussed. We specifically validate the usage of a Historical Simulation/VaR approach for managing the risk when acting as a CCP for the Non Delivery Forward FX instrument. The method is back tested and some alternative approaches are proposed.
Sedan finanskrisen 2008 har regelverken för central clearing av OTC handlade produkter stärkts. I Europa tvingar EMIR regelverket in de OTC handlade financiella produkter att clearas på ett så kallad CCP Clearinghus. Mer och mer av dessa finansiella produkter kommer nu cleareas på clearinghusen. Clearinghusen blir därmed mer och mer riskabla och ett antal studier har gjorts angående vad denna komplexa miljö kan innebära i form av spridningseffekt etc. Därför är det av stor vikt att clearinghusen kan hantera risken som det innebär att clearea dessa nya produkter. Ett exempel på sådan centralt clearad produkt är FX instrument som tex NDF. På NASDAQ Clearing så är förslaget att använda Historical Simultion/VaR för att räkna ut de säkerheter som ska tas in från medlemmarna. ESMA ställer vissa krav på denna modell men är i övrigt positivt inställda till just HS/VaR. Jag har i detta arbete redogjort för hur ett clearinghus fungerar, hur ett FX instrument som NDF fungerar och slutligen gjort en Back test av HS/VaR som riskmått för en NDF portfölj. Speciellt fokuserar jag på hur denna modell skulle ha klarat den turbulenta perioden under 2008/2009 med efterföljande lugna period. Back testet visar att den inte skulle vara lämplig under denna period och avslutningsvis diskuterar jag runt några alternativa adaptioner för att modellen skulle vara bättre anpassad till karakteristiken i FX tidsserien.
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37

Bouet, Jean-Yves. "Caractérisation du gène ndd du bactériophage T4. Etude de l'effet de la protéine NDD sur le nucléoi͏̈de bactérien." Toulouse 3, 1996. http://www.theses.fr/1996TOU30139.

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Chez la bacterie escherichia coli, l'adn genomique est constitue d'une molecule circulaire de 4,6 10#6 paires de bases. Cette molecule d'adn doit etre organise pour permettre a la fois sa condensation dans la cellule et les activites transcriptionnelles et replicatives continuelles caracteristiques des procaryotes. Cependant l'organisation generale des chromosomes bacteriens est encore largement enigmatique. Les travaux presentes dans ce memoire s'inscrivent dans le cadre de l'analyse a grande echelle du nucleoide bacterien. Nous nous sommes interesse a l'etude d'un phenomene physiologique induit par le bacteriophage t4, la disruption nucleaire. En effet, en quelques minutes, le produit du gene phagique ndd est capable de detruire completement l'organisation du nucleoide. La proteine ndd pourrait donc etre un moyen d'investigation de la structure et de l'organisation du chromosome bacterien. L'introduction generale presente les donnees acquises concernant la structure et l'organisation du chromosome bacterien. Les principaux resultats obtenus au cours de ce travail sont publies. Le premier article (gene, 1994) concerne l'identification du gene ndd et sa conservation importante parmi l'ensemble de la famille des bacteriophages t-pairs. Le second article (mol. Microbiol. , 1996) presente les effets physiologiques de l'expression du gene ndd clone. Les resultats obtenus ont permis de montrer que la proteine ndd est, a elle seule, capable de provoquer le phenomene de disruption nucleaire. Cette desorganisation complete du nucleoide, accompagnee d'une importante letalite des cellules, est realise sans la moindre destruction de l'adn chromosomique. L'ensemble des resultats est consistant avec une alteration specifique d'elements structuraux du nucleoide provoquee par la proteine ndd. D'autre part, l'etude de la proteine ndd thermosensible a permis de montrer qu'elle possede, in vitro, une activite de liaison a l'adn double brin. Les donnees presentees dans ce memoire sont discutees dans le dernier chapitre. Elles confirment amplement notre hypothese d'utiliser ndd comme moyen d'investigation de la structure du chromosome bacterien
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Preda, Cristina-Elena. "Laser Nd3+:YVO4: dynamique et conduite optimale." Phd thesis, Université des Sciences et Technologie de Lille - Lille I, 2007. http://tel.archives-ouvertes.fr/tel-00169859.

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Ce travail s'inscrit dans le cadre général de l'étude de la dynamique des lasers de classe B. Trois aspects sont abordés concernant respectivement la génération d'impulsions de forme arbitraire, la validation de modèles de lasers existants et la mise en évidence d'effets "cliquet" dans la dynamique de ces lasers.
Une première partie présente deux méthodes mises au point pour la génération d'impulsions de forme arbitraire (triangle, gaussienne, impulsion à deux bosses) en dépit de la propension du laser à fournir des impulsions "sécante-hyperbolique". Dans les deux cas un Algorithme Génétique (AG) détermine les paramètres du signal de conduite optimal. Si pour la première méthode ce signal est construit à partir de fonctions élémentaires, pour la seconde il résulte d'une interpolation entre points de collocation fixés par l'AG.
Les outils développés (couplage captures rapides/traitements en temps réel par AG) ont été mis à profit pour étudier la validité des différents modèles décrivant la dynamique des lasers de classe B fonctionnant en régime monomode ou bi-raie. L'AG est alors utilisé pour comparer l'évolution temporelle de l'intensité émise par le laser à celle calculée à partir du modèle. Ils permettent ainsi d'identifier le modèle le mieux adapté et de déterminer ses paramètres.
La bonne connaissance que nous avons de la dynamique de notre laser nous a incité à effectuer une étude détaillée d'effets étonnants induits par une modulation temporelle asymétrique du pompage. Les expériences réalisées constituent la première mise en évidence sur un laser d'un effet "cliquets" similaire à celui proposé par Feynman pour extraire de l'énergie d'un mouvement erratique.
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39

Kocak, Okan Okay. "Defect Assessment Of Spot Welds By Ndi." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/4/1027382/index.pdf.

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Resistance spot welding is used frequently as a successful joining method for a variety of work commonly in automotive and other manufacturing processes. Spot weld nugget is generally hidden between two sheets, causing its inspection difficult and expensive. Undersized nuggets, brittle or cracked nuggets, and excessive indentation of electrodes reveals the lack of fusion between the parts that can make the weld sub-standard. Visual inspection, pry testing and physical teardown with chisel and hammer method or a combination of them are being used traditionally. However, this study presents a more effective nondestructive inspection method based upon an ultrasonic pulse-echo technique. The theory of the technique together with the experimental verification are presented and its advantages over the other destructive and nondestructive techniques are considered.
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40

Morin-Leisk, Jeanne. "NDKB and Atlastin Structure Endoplasmic Reticulum Membranes." Research Showcase @ CMU, 2011. http://repository.cmu.edu/dissertations/153.

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Of the membrane bound organelles in eukaryotic cells, the endoplasmic reticulum (ER) may be the most complex. It is the largest both in terms of surface area and volume. It includes several subdomains: the nuclear envelope (NE) as well as an extensive network of both highly inter-connected fenestrated tubular membranes and flat cisternal sheets (1, 2). While the structure and organization of the ER is thought to be important for the execution of a myriad of essential cellular functions including protein and lipid synthesis and export as well as calcium sequestration and drug metabolism (3), how this membrane system is generated and maintained despite continuous turnover is only just beginning to be unraveled (4). The microtubule cytoskeleton and molecular motors are clearly important for the extension of tubules from the existing network so that they may fuse with nearby ER tubules to generate new three-way junctions (5-8). However, an ER-like network can be generated in vitro in the absence of microtubules (9), which suggests the existence of additional mechanisms for the extension and scaffolding of the ER network. Once the tubular ER does extend out from the existing network the next critical step is fusion. Soluble NSF attachment-protein receptors (SNAREs) were an obvious candidate for this role (10), but ER homotypic fusion events have not yet been found to depend on SNAREs. Recently, a member of the dynamin super-family of large GTPases, atlastin, was implicated in ER homotypic fusion. An in vitro fusion assay (11) and knockdown experiments (12) in conjunction with the crystal structures of the soluble domains of atlastin (13, 14) have led to a possible mechanism of ER fusion, but this model remains to be tested. In my thesis I will describe two projects. One focuses on the role and mechanism of nucleoside diphosphate kinase B (NDKB) in ER network extension and stabilization. The other focuses on the role and mechanism of atlastin in fusing ER membranes. NDKB was initially implicated as a stimulator of ER export in permeabilized cells (15). Subsequent work suggested that its effect on ER export might be through an effect on ER network morphology. Through in vitro assays, we found that NDKB not only stabilizes the ER network but also actively promotes ER network extension. In order to perform this function we hypothesized that it might interact directly with ER membranes. Indeed, we found a pair of positively charged residues that mediated direct binding of NDKB to anionic phospholipids. When these residues ware mutated to negatively charged residues, NDKB no longer bound anionic phospholipids and failed to mediate ER extension in our semi-intact cell assay. In order to gain insight into the mechanism for how NDKB might be performing its ER network extension function we took another in vitro approach. Anionic synthetic liposomes were incubated with NDKB and we found that NDKB was able to arrange these liposomes into large arrays that resembled the ER network. Together these results implicate NDKB and anionic phospholipids in a role for ER network morphology, in particular as a means to stabilize and extend the ER network. We initially became interested in the atlastin GTPase as a result of an ER overexpression phenotype observed by the Blackstone lab indicating a potential role in ER morphogenesis (16). In strong support for a required role for atlastin in ER structuring, we found that siRNA depletion of atlastin from HeLa cells resulted in a reduction in network density which could be rescued by the addition of an siRNA immune atlastin transgene. This established a structure function assay we could use to dissect the functional domains of atlastin. Concurrent with our identification of key residues required for atlastin function, it was observed by another lab that atlastin could fuse synthetic liposomes (11), suggesting that the ER structuring role we had observed for atlastin might correspond to the membrane fusion step. Simultaneously, structure determinations for the soluble domain of atlastin were reported (13, 14). Together, the collective data suggested the following model for atlastin: GTP dependent dimerization of atlastin leads to tethering and subsequent GTP hydrolysis leads to a large conformational change that drives membrane fusion (13, 14). To test the model, we exploited our identification of a required salt bridge central to the large conformational change proposed to convert GTP-bound tethered atlastin dimers into a postfusion state. We established that although blocking the salt bridge had no effect on GTP binding and hydrolysis, it abolished stable atlastin dimer formation. Then, through a series of crosslinking assays probing the conformational state of the atlastin soluble domain, we showed that atlastin adopts the postfusion conformation in the GTP bound state, without the need for GTP hydrolysis. As a result of our studies, we have modified the current model for atlastin’s function. In our revised model, GTP binding is required for atlastin’s initial dimerization and begins a cascade of conformational changes that results in the large rearrangement thought to drive membrane fusion. We speculate based on our work that hydrolysis may be necessary to complete the fusion cycle and/or function to disassemble the postfusion complex for multiple rounds of fusion. In summary, these studies provide both an initial analysis of a protein with an ER network extension role and important insights into the mechanism of ER membrane fusion. It is hoped that this work will add to our understanding of the biogenesis and maintenance of the ER network.
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41

Gonçalves, Dany Thomaz. "Pronúncia variável de (NDO) na fala paulistana." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/8/8139/tde-15032019-112642/.

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Essa dissertação trata da pronúncia variável de /ndo/, com /d/ apagado ou pronunciado. Baseada na teoria e metodologias da Sociolinguística Variacionista (LABOV, 2006[1966], 2008[1972]), focaliza tal variável aqui referida como (NDO) na variedade paulistana do português brasileiro, através das 60 entrevistas do Projeto SP2010 (MENDES & OUSHIRO, 2012), estratificadas por Sexo/Gênero, Faixa Etária e Escolaridade. A variável (NDO) tem sido estudada desde o final dos anos 70 sob diferentes perspectivas. Alguns pesquisadores se atêm à pronúncia variável do sufixo de gerúndio (por exemplo, falano ou falando em diferentes variedades do português: Rio de Janeiro (MOLLICA, 1989), Belo Horizonte (CRISTÓFARO SILVA, 1996), João Pessoa (MARTINS, 1999, 2001), Minas Gerais (MARTINS, 2006), São José do Rio Preto (FERREIRA, 2010), Dourados e Ponta Porã MS (MARTINS e BUENO, 2011), Taboco MS (VIEIRA, 2011), Fortaleza (NASCIMENTO ET AL., 2013), Maceió (ALMEIDA e OLIVEIRA, 2017)). Leva-se em consideração o apagamento de /d/ como uma variável cujo padrão de realização pode ter especificidades na fala paulistana uma variedade que, ainda que mais detidamente estudada nos últimos anos, ainda não foi analisada no que toca a (NDO), nem no gerúndio, especificamente, nem em outros contextos morfológicos ou itens lexicais, tal como na palavra quando. O objetivo central é, então, investigar quais as variáveis linguísticas e sociais que se correlacionam à realização de (NDO). Para tanto, analisou-se qualitativa e quantitativamente a amostra, onde foram encontrados casos de apagamento de /d/ na pronúncia da Conjunção quando (93/1557) e em verbos no gerúndio (1001/4143). Segundo as análises estatísticas multivariadas, verificou-se que não há correlação significativa entre (NDO) e nenhuma das variáveis linguísticas, o apagamento ocorre com maior frequência na fala dos homens, sendo mais propício na fala daqueles com menor grau de instrução, assim como ocorre para aqueles falantes da Classe Social menos favorecida. Com relação à Faixa Etária, existe um favorecimento na fala dos mais jovens, principalmente naqueles da Faixa Etária intermediária, já para a terceira faixa existe um desfavorecimento, esses resultados levam a indícios de que o apagamento de /d/ em (NDO) seja uma variável estável na capital paulista.
This masters thesis deals with /ndo/ variable pronunciation, with /d/ deletion or pronunciation. Based on Variationist Sociolinguistics theory and methodologies (LABOV, 2006[1966], 2008[1972]), we focus on this variable here called as (NDO) on São Paulos speech of Brazilian Portuguese, through 60 interviews from SP2010 project (MENDES & OUSHIRO, 2012), stratified by Sex/Gender, Age and Level of Education. The variable (NDO) has been studied since the 1970s from different perspectives. Some researchers focused only on the pronunciation of the suffix of gerund (for example, falano or falando in different portuguese varieties as Rio de Janeiro (MOLLICA, 1989), Belo Horizonte (CRISTÓFARO SILVA, 1996), João Pessoa (MARTINS, 1999, 2001), Minas Gerais (MARTINS, 2006), São José do Rio Preto (FERREIRA, 2010), Dourados and Ponta Porã MS (MARTINS e BUENO, 2011), Taboco MS (VIEIRA, 2011), Fortaleza (NASCIMENTO ET AL., 2013), Maceió (ALMEIDA e OLIVEIRA, 2017)). Taking into account the deletion of /d/ as a variable in which the performance pattern may have specificities in Paulistano speech - a variety that, although studied in recent years, has not yet been analyzed regarding (NDO), nor in the gerund, specifically, nor in other morphological contexts or lexical items, as in the word quando. The main goal is to investigate the linguistic and social variables that are correlated to the performance of (NDO). For that, the sample was analyzed qualitatively and quantitatively, in which cases of deletion of /d/ were found in the pronunciation of the conjunction \"quando\" (93/1557) and in verbs in the gerund (1001/4143). According to the multivariate statistical analysis, it was verified that there is no significant correlation between (NDO) and the linguistic variables, deletion occurs more frequently in men\'s speech, being more propitious in the speech of those with lower Education Degree, as it occurs for those speakers of the less favored Social Class. Regarding the Age Range, there is a favoring of young people\'s speech, at all levels, the results lead to an indication that the /d/ deletion in (NDO) is a variable stability in São Paulo city.
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42

Baldwin, Ian Alan. "EROBOT : a second-generation NDE inspection robot." Master's thesis, University of Cape Town, 2007. http://hdl.handle.net/11427/5550.

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43

Garnier, Nicolas. "Spectroscopie dans l'état excité des ions terres-rares Nd3+ et Tm3+ et fonctionnement laser multilongueur d'onde du YAG : Nd3+." Saint-Etienne, 1997. http://www.theses.fr/1997STET4020.

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L'ensemble des travaux présentés dans cette thèse a été réalisé dans le cadre du Groupement de recherche matériaux lasers (GDR CNRS n°1148, thème : critère de qualité). Il est issu d'une collaboration entre le Laboratoire Traitement du signal et instrumentation, le Laboratoire Physico-chimie des matériaux luminescents et les entreprises CRISMATEC et BM industrie. Ces travaux ont conduit à la mise en oeuvre de différentes techniques expérimentales permettant la compréhension de divers processus se manifestant par une limitation de l'effet laser dans les cristaux de YAG : Nd3+ (Y3al 5o 1 2 : Nd3+) et YLF : Nd3+ (YLIF4 : Nd3+). Le premier aspect de ces processus est lié à l'ion dopant, ce sont des processus intrinsèques tels que l'absorption dans l'état excité et l'addition de photon par transfert d'énergie conduisant à un dépeuplement du niveau métastable émetteur dans l'infrarouge. Nous avons mis au point différentes expériences à deux faisceaux laser synchronisés (pompe, sonde) permettant l'étude des transitions dans l'état excité tant du point de vue spectral que des sections efficaces. Dans le cas du YLF : Nd3+, ces techniques ont permis la mise en évidence d'un double processus d'addition de photons par transfert d'énergie conduisant à des émissions visibles et ultraviolettes faisant suite à un pompage infrarouge ainsi qu'une double absorption dans l'état excité autour de la longueur d'onde laser (1. 05 m). Nous avons par ailleurs appliqué ces techniques à l'étude de transitions d'absorption dans l'état excité intervenant dans le processus d'avalanche de photons dans l'ion thulium pour différentes matrices (Y3al 5o 1 2, YALO3 et Y2O3). Le second aspect de ces travaux, appliqué au YAG : Nd3+, nous a conduit à envisager l'intervention d'un processus extrinsèque à l'ion dopant lié à la formation de centres colorés après pompage optique. On observe ainsi, après pompage, la diminution d'une bande d'absorption autour de 250 nm n'appartenant pas à l'ion Nd3+, l'apparition d'une bande d'absorption s'étendant depuis le visible jusqu'à l'infrarouge conduisant ainsi à l'augmentation de l'absorption résiduelle à la longueur d'onde laser (1. 064 m), cette absorption résiduelle étant mesurée par une technique interférométrique spécialement développée à cet effet. Le processus envisagé est le changement de Valence d'une impureté (probablement du fer) par piégeage d'un électron libéré dans la matrice YAG sous l'effet du rayonnement ultraviolet des flashes de pompage, processus partiellement réversible, avec la création de centres absorbants sous forte intensité de pompage (phénomène à deux photons) et annihilation (blanchiment) de ces centres sous faible intensité de pompage (phénomène à un photon). L'hypothèse actuelle, quant à la nature de ces centres, serait liée au processus d'oxydo-réduction : Fe3+ + e- Fe2+. Nous avons observé que ces centres colorés avaient une influence sur l'énergie extraite et sur la thermique des barreaux en fonctionnement laser
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44

Ward, Christopher M. S. "Novel NDE techniques in the power generation industry." Thesis, University of Nottingham, 2010. http://eprints.nottingham.ac.uk/11656/.

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The thesis presented here comprises the work undertaken for research into novel NDE techniques in the power generation industry. This has been undertaken as part of the Engineering Doctorate Scheme run by the Research Centre for Non-Destructive Evaluation (RCNDE), which aims to bridge the technological gap between university research and industrial application. In this case, the scheme consisted of two projects completed in conjunction with RWE npower looking at current NDE problems in steam turbine and steam-raising plant. The first project was concerned with detecting microstructural transformation in steam turbine blades, which can act as a precursor to failure by environmentally assisted cracking. This project, and indeed, this entire thesis is principally based on electromagnetic testing methods. An eddy current technique for mapping the microstructural phases was produced and validated as far as was achievable; this offered a significant time-saving advantage over the previous method, by reducing inspection time from 5 man days to just 1.5. The technique has novelty in producing a 2-dimensional map of the blade surface which highlights areas where microstructural phases differ. The second project focuses on the detection of microstructural damage associated with material creep life expiry. This forms a review of the current state of technology and highlights potentially useful paths for future research in both established and emerging NDE technologies, including Magnetic Barkhausen Noise testing and laser-generated ultrasound. Both projects have provided tangible benefit to the sponsoring company and have pushed forward research in a number of technological applications.
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45

Smith, Ian Colin. "Vision based systems for hardness testing and NDT." Thesis, University of Liverpool, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317273.

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The work presented in this thesis concerns the development of vision based systems for two hardness (destructive) tests, namely; the Shore and Vickers and a quality assurance non-destructive test. In each case the vision system is based on an IBM PC compatible computer fitted with a commercially available frame store. Bespoke image analysis software was written using the C language for each system. In the Shore test, hardness is judged by the maximum rebound height attained by an indenter incident on a test sample. The purpose of the vision system is to measure the rebound height automatically. Laser light is used to illuminate the indenter and a vidicon vision camera is used to view its motion. Two approaches to the problem are considered; one in which image data is analysed in real time and one in which image·data is merely stored in real time and analysed a posteriori. Non-real time analysis is shown to be superior to real time analysis in terms of accuracy and reliablity and its software implementation is discussed in detail. The Vickers test uses the size of the permanent impression left by an indenter forced into the test material under a known load as a hardness index. In this case the purpose of the vision system is to measure the size of the indentation automatically. The original image analysis algorithms are shown to be capable of analysing good quality samples but are unreliable when applied to poor quality specimens. Further, fault-tolerant, algorithms are described to provide reliable and accurate results over wide variations in sample quality.The quality assurance application involves automated visual inspection of novel ferrite components for defects. Each component is approximately 8 mm in diameter, annular in shape, and coated with aluminium. Laser light is used to illuminate individual components which arc viewed using a charge-coupled device (CCD) video camera. Image analysis algorithms for characterising defects in component geometry and surface finish arc discussed. The system is shown to capable of measuring component edge eccentricity and hole offset as well as providing a quantitative description of surface chips and cracks. The system is further shown to be capable of separately classifying surface defects extending to the edge of a component. Calculation of shape parameters for surface defects also provides a means of distinguishing cracks from surface chips.
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46

McAughey, Kevin L. "High precision measurements for NDE using electromagnetic sensors." Thesis, University of Warwick, 2014. http://wrap.warwick.ac.uk/72801/.

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47

Begum, Rushna. "Neural network processing of impact echo NDT data." Thesis, City University London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340456.

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48

Jarvis, Rollo. "Current deflection NDE for pipe inspection and monitoring." Thesis, Imperial College London, 2017. http://hdl.handle.net/10044/1/56865.

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The detection of corrosion on insulated and/or coated pipes in the oil and gas industry remains a challenge. Routine inspection, which is commonly achieved with in-line tools known as "pigs", is not possible where there is any risk of the pig becoming stuck. There are thousands of kilometers of pipe worldwide deemed ''unpiggable'' whose safety must be ensured using Non-Destructive Evaluation (NDE) external to the pipe if potentially catastrophic failure is to be avoided. Many NDE techniques lack sufficient sensitivity due to the coating thickness producing a high standoff distance between the pipe and the sensor and therefore require costly and time-consuming removal of the coating. A method capable of detecting and/or monitoring of defects (e.g. one-third-wall depth corrosion) while leaving the insulation/coating intact would be highly attractive. This thesis documents the development of a technique in which a low-frequency AC current is directly injected into the pipe at distant locations, and perturbations in the magnetic field caused by "current deflection" around defects are measured using solid-state magnetic sensors. Two methods of applying this novel technique were investigated. Firstly, scanning the sensors to measure perturbations in the field and screen for defects, and secondly, permanently installing sensors outside the pipe for Structural Health Monitoring (SHM). A Finite Element (FE) model has been developed and used to investigate the practical challenges that are faced by the technique and how these may be overcome. The sensitivity of the technique for defect detection by external pipe scanning in a practical scenario has then been evaluated using a model-assisted Probability of Detection (POD) framework that combines the measurements of the signal from an undamaged pipe with synthetic damage profiles and contributions from general corrosion and sensor misalignment. The results indicate that good performance is expected for damage detection by scanning above a typical insulation thickness with just a few amps of injected current. A similar framework has then been used to evaluate the sensitivity of the technique as an SHM solution which suggests excellent corrosion detection performance with the permanent installation of inexpensive magnetic sensors. The technique has potential advantages over competing methods in both scanning and monitoring modes and there are many opportunities for future development.
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49

Yin, Xiaokang. "Capacitive imaging technique for non-destructive evaluation (NDE)." Thesis, University of Warwick, 2011. http://wrap.warwick.ac.uk/35790/.

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This thesis describes the development and characterization of a novel NDE methodthe Capacitive Imaging (CI) technique. The CI technique employs a pair of (or multiple) electrodes to form a co-planar capacitor, and uses the fringing quasi-static electric field established across the electrodes to investigate specimens of interest. In general, the CI probe is sensitive to surface and hidden defects in insulating materials, and surface features on conducting materials. The CI technique is advantageous for its non-contact and non-invasive nature, and the capacitive coupling allows the CI technique to work on a wide variety of material properties. The theoretical background to the CI technique has been developed. It is shown that in the frequency range of operation (10 kHz to 1 MHz), the quasi-static approximation is valid and the Maxwell’s Equations describing the general electromagnetic phenomena can be simplified. The practical implementation of the CI system is based on this analysis, and it is shown that the CI technique has features that can complement techniques such as eddy current methods that are already established in NDE. The design principles of the CI probes that are required for an optimum imaging performance have been determined, by considering the key measures of the performance including the depth of penetration, the measurement sensitivity, the imaging resolution and the signal to noise ratio (SNR). It has been shown that the operation frequency is not an influential factor - the performance of the CI probe is determined primarily by the geometry of the probe (e.g. size/shape of the electrodes, separation between electrodes, guard electrodes etc.). Symmetric CI probes with triangular-shaped electrodes were identified as a good general purpose design. Finite Element (FE) models were constructed both in 2D and 3D in COMSOLTM to predict the electric field distributions from CI probes. Effects of thickness of specimen, liftoff distance and relative permittivity value etc were examined using the 2D models. The sensitivity distributions of different CI probes were obtained from the 3D models and were used to characterize the imaging ability of the given CI probes. The fundamental concepts of the CI technique have been experimentally validated in a series of scans where the defects were successfully imaged in insulating (Perspex) and conducting (e.g. Aluminium, Steel and carbon fibre composite) specimens. The detection of corrosion under insulation (CUI) has also been demonstrated. The imaging abilities were assessed by investigating various standard specimens under different situations. The CI technique was then successfully applied to various practical specimens, including glass fibre laminated composites and sandwich structures, laminated carbon fibre composites, corroded steel plate and pipe, and concrete specimens. Further measurements were also conducted using modified CI probes, to demonstrate the wide range of applications of the CI technique.
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50

Henriksson, Johan. "Radar odometry based on Fuzzy-NDT scan registration." Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-94492.

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Visual and lidar-based odometry for mobile robots has been thoroughlyinvestigated and performs very well in good weather conditions. However,both are sensitive to bad weather conditions with atmospheric disturbancessuch as rain and snow. Recently Radar sensors specialized for mobilerobot use have become available. Radar sensors are much more robustagainst atmospheric disturbances, which makes them an exciting alternative.This thesis presents a radar odometry pipeline that can handle both lidar andradar data with minor modifications. The results show that it outperformsthe current state of the art radar odometry solutions. While also being able tohandle 3d lidar odometry with good performance.
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