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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Ultrafine particle generation and measurement

Liu, Qiaoling 01 January 2015 (has links)
Ultrafine particles (UFPs) with diameters smaller than 100 nm are omnipresent in ambient air. They are important sources for fine particles produced through the agglomeration and/or vapor condensation. With their unique properties, UFPs have also been manufactured for industrial applications. But, from the toxicological and health perspective, ultrafine particles with high surface-to-volume ratios often have high bio-availability and toxicity. Many recent epidemiologic studies have evidence UFPs are highly relevant to human health and disease. In order to better investigate UFPs, better instrumentation and measurement techniques for UFPs are thus in need. The overall objective of this dissertation is to advance out current knowledge on UFPs generation and measurement. Accordingly, it has two major parts: (1) ultrafine particle generation for laboratory aerosol research via electrospray (ES), and (2) ultrafine particle measurement for ambient aerosol monitor and personal exposure study via the development of a cost-effective and compact electrical mobility particle sizer. In the first part, to provide monodisperse nanoparticles, a new single capillary electrospray with a soft X-ray photoionizer as a charge reduction scheme has been developed. The soft X-ray effects on electrospray operation, particle size distribution and particle charge reduction were evaluated. To generate ultrafine particles with sufficient mass concentration for exposure/toxicity study, a TSE twin-head electrospray (THES) was evaluated, as well. The configuration and operational variables of the studied THES has been optimized. Three different nanoparticle suspensions were sprayed to investigate material difference. In the second part, to develop a miniature electrical mobility based ultrafine particle sizer (mini e-UPS), a new mini-plate aerosol charger and a new mini-plate differential mobility analyzer (DMA) have been developed. The performances of mini-plate charger and mini-plate DMA were carefully evaluated for ultrafine particles, including intrinsic/extrinsic charging, extrinsic charge distribution, DMA sizing accuracy and DMA transfer function. A prototype mini e-UPS was then assembled and tested by laboratory generated aerosol. Also a constrained least square method was applied to recover the particle size distribution from the current measured by a mini Faraday Cage aerosol electrometer.
62

Instant Feedback Loops – for short feedback loops and early quality assurance

Mehraban, Mehrdad January 2016 (has links)
Context. In recent years, Software Quality Assurance (SQA) has become a crucial part of software development processes. Therefore, modern software development processes led to an increase in demand for manual and automated code quality assurance. Manual code quality reviews can be a time-consuming and expensive process with varying results. Thus, automated code reviews turn out to be a preferred alternative for mitigating this process. However, commercial and open-source static code analyzer tools often offer deep analysis with long lead time. Objectives. In this thesis work, the main aim is to introduce an early code quality assurance tool, which features a combination of software metrics. The tool should be able to examine code quality and complexity of a telecommunication grade software product such as source code of specific Ericsson product by Ericsson. This tool should encapsulate complexity and quality of a software product with regards to its efficiency, scope, flexibility, and execution time. Methods. For this purpose, the background section of the thesis is dedicated to in-depth research on software metrics included in well-known static code analyzers. Then, development environment, under investigation source code of Ericsson product, and collected software metric for evaluation were presented. Next, according to each software metric’s characteristics, point of interest, and requirement, a set of steps based on a Susman’s action research cycle were defined. Moreover, SWAT, a suitable software analytics toolkit, employed to extract conducted experiment data of each software metric from a static analyzer code named Lizard in order to detect most efficient software metrics. Outcome of conducted experiment demonstrates relationship of selected software metrics with one another. Results. The chosen software metrics were evaluated based on a variety of vital factors especially actual data from number of defects of specific Ericsson product. Highly effective software metrics from investigations in this thesis work were implemented as a new model named hybrid model to be utilized as an early quality assurance. Conclusions. The proposed model, which consist of well-performing software metrics, demonstrate an impressive performance as an early code quality indicator. Consequently, the utilized model in this master thesis could be studied in a future research to further investigate the effectiveness and robustness of this tool an early quality assurance.
63

"Influência da mochila em parâmetros dinâmicos, cinemáticos e fisiológicos da locomoção de carteiros pedestres" / DYNAMICS, KINEMATICS AND PHYSIOLOGICALS EFFECTS OF USING DIFFERENTS TYPES OS MAILBAGS

Peneireiro, Germano Mongeli 11 April 2006 (has links)
O objetivo deste estudo foi determinar a influência das características de três tipos de mochila através de parâmetros biomecânicos e fisiológicos selecionados. Foram voluntários 49 carteiros (30±7 anos, 1,74±0,62 m e 72,6±11,8 kg), que utilizaram 3 tipos de mochilas: mochila lateral simples (MLS), mochila lateral com cinto pélvico (MLCP) e mochila dupla com cinto pélvico (MDCP). Os sujeitos andaram durante 10 minutos sobre esteira rolante Trotter instrumentada com duas plataformas de força de reação do solo Kistler, utilizando um analisador de gases que analisou os gases expirados. As variáveis cinéticas da locomoção apresentaram diferenças significativas entre as mochilas. As variáveis cinemáticas não mostraram diferenças significativas. A ventilação apresentou diferenças entre MLCP (23,2±5,4 L · min-1) e MLS (22,5±5,0 L · min-1) e MDCP (22,3±4,8 L · min-1) e o consumo de oxigênio apresentou diferenças entre MDCP (14,6±4,1 mL · kg-1 · min-1) e MLS (15,1±3,6 mL · kg-1 · min-1) e MLCP (15,2±4,3 mL · kg-1 · min-1). Os dados dinâmicos apontaram para benefícios do uso da MLS, e os dados fisiológicos apontaram para benefícios do uso da MDCP. Embora os dados tenham apresentado diferenças estatísticas, estas não foram de magnitudes representativas, assim, a MDCP parece induzir maior demanda metabólica e a MLS menor estresse físico. / The aim of this study was to determine the influence of the satchel construction characteristics in selected biomechanical and physiological parameters during the accomplishment of the locomotion of mailmen pedestrians. 49 mailmen had been voluntary (30±7 years, 1.74±0.62 m and 72.6±11.8 kg), which had used 3 types of satchels, simple lateral satchel (MLS), lateral satchel with pelvic belt (MLCP) and double satchel with pelvic belt (MDCP). The subjects had walked 10 minutes on Trotter treadmill instrumented with two Kistler force platforms, using a gas analyzer that made analyzes of the exhaled gases. Fy1 presented differences between MLS (1.35±0.10) and MLCP (1.37±0.11) and MDCP (1.37±0.10), like others FRS parameters. The step and strike lengths had not been sensible to the different satchels. The VE presented differences between MLCP (23.2±5.4 L · min-1) and MLS (22.5± 5.0 L · min-1) and MDCP (22.7±4.8 L · min-1) and the VO2, presented differences between MDCP (14.6± .1 mL · kg-1 · min-1) and MLS (15.1±3. 6 mL · kg-1 · min-1) and MLCP (15.2±4.3 mL · kg-1 · min-1). The dynamic data had pointed to benefits using MLS, but the physiological data had indicated to benefits using MDCP. Although the data have presented statistical differences, but these had not been representative magnitudes, thus, the MDCP seems to induce bigger metabolic demand and MLS the lesser physical stress.
64

Development of a Micro-Retarding Potential Analyzer for High-Density Flowing Plasmas

Partridge, James M 10 November 2005 (has links)
"The development of Retarding Potential Analyzers (RPAs) capable of measuring high-density stationary and flowing plasmas is presented. These new plasma diagnostics address the limitations of existing RPAs and can operate in plasmas with electron densities in excess of 1x1018 m-3. Such plasmas can be produced by high-powered Hall Thrusters, Pulsed Plasma Thrusters (PPTs), and other plasma sources. The Single-Channel micro-Retarding Potential Analyzer (SC-microRPA) developed has a minimum channel diameter of 200 microns, electrode spacing on the sub-millimeter scale and can operate in plasmas with densities of up to 1x1017 m-3. The electrode series consists of 100 micron thick molybdenum electrodes and Teflon insulating spacers. The alignment process of the channel, as well as the design and fabrication of the stainless steel outer housing, the Delrin insulating tube, and all other microRPA components are detailed. To expand the applicability of the SC-microRPA to densities above 1x1018 m-3 a low transparency Microchannel Plate (MCP) has been incorporated in the design of a Multi-Channel micro-Retarding Potential Analyzer (MC-microRPA). The current collection theory for the SC-microRPA and the MC-microRPA is also derived. The theory is applicable to microRPAs with arbitrary channel length to diameter ratios and accounts for the reduction of ion flux due to the microchannel plate in the case of the MC-microRPA, due to absorption of ions by channel walls, and due to the applied potential. Current-voltage curves are obtained for incoming plasma flows that range from near-stationary to hypersonic, with temperatures in the range of 0.1 to 10 eV, and densities in the range of 1x1015 m-3 to 1x1021 m-3. The SC-microRPA current collection theory is validated by comparisons with the classical RPA theory and particle-in-cell simulations. Determination of unknown plasma properties is based on a fuzzy-logic approach that uses the generated current-voltage curves as lookup tables."
65

Parallel Comparison of Accuracy in Vitek2 Auto analyzer and API 20 E / API 20 NE Microsystems

Darbandi, Fazel January 2011 (has links)
302 samples were evaluated in the present study including 50 standard quality control samples, 62 repeatability samples and two separate batches of 90 and 100 samples of clinical isolates. Standard samples with registered ATCC or CCUG codes taken from international reference lab, used for performance test (quality control) of Vitek2 compact analyzer. The results of performance test showed total 98% accuracy. Detailed performance test results showed 100% accuracy for Gram positive & Gram negative bacteria and 95% accuracy for NH group members.Comparison between results of different culture media showed that use of conventional culture media instead of commercial branded culture media for preparing bacterial suspensions, doesn’t affect the result’s accuracy level in Vitek2 analyzer.Repeatability and reproducibility study of 62 samples including standard & clinical isolates results, showed 96.8% coalition in reproduced results by Vitek2 analyzer.The comparative results of 90 clinical samples via API 20E / API 20NE Microsystems and Vitek2 compact analyzer showed 77.8% “Complete coalition” or coalition in the "genus" and "species" levels of isolated micro organisms, 10.0% “partial coalition” which means coalition in the "genus" level but difference in "species” of isolates, 6.7% “no coalition” or different results in the "genus" and "species" levels of isolated micro organisms and 5.5% “unidentified” micro organisms by one of the applied methods. Comparative results also showed that total acceptable results rose from 80% in API system to 90% in vitek2 analyzer for clinical samples in this study.Survey on a random selection of 100 samples of Vitek2 reports showed an average analyze time of 5.5 hrs (330 Min.), where the minimum and maximum observed time were 2.75 hrs and 10.25 hrs respectively. Findings in this survey also showed 94% excellent, very good and acceptable identification of bacterial strain, 4% low discrimination, 2% non reactive bio-pattern and unidentified organism. The abundance of different bacteria in the random collection was composed of 71% gram negative, 24% gram positive and 5% NH group members. Escherichia coli (23.2% of total) were the popular bacteria in this collection.
66

Proposta de equipamento para medição dos fenômenos relativos à qualidade da energia elétrica utilizando conceitos de instrumentos virtuais / Power quality measuring equipment proposal based on virtual instruments conception

Matana, Gleison Melhado 15 April 2008 (has links)
Este trabalho apresenta um estudo da literatura pertinente sobre qualidade da energia elétrica. O estudo apresentado está baseado na evolução do tema em nível nacional e internacional, buscando explicar o conceito dos principais fenômenos e selecionar as recentes resoluções e normas que regem os princípios de medição e os limites dos distúrbios eletromagnéticos que os caracterizam. As normas da IEC foram selecionadas para a aplicação na construção de um protótipo de um medidor de qualidade da energia elétrica, onde o princípio construtivo é o de instrumento virtual por sua flexibilidade de arquitetura. A implementação do protótipo dá-se em um microcomputador padrão de mercado pelo software LabVIEW, através de vários módulos independentes para cada distúrbio a ser medido. Os resultados numéricos das simulações executadas frente a cada distúrbio, gerando comparações entre valores aplicados e valores medidos são apresentados em forma de tabelas com seus respectivos erros percentuais para cada grandeza de cada módulo. / This dissertation presents a study of existing literature about power quality. The study presented is based on a theme evolution in national and international environment, trying to explain the main phenomenon conceptions and select the most recent standards that rule the measurement conceptions and the electromagnetic disturbances limits that characterize it. The IEC standard were selected to build a prototype of a power quality measure device where the construction conception is a virtual instrument because it has a flexible architecture. The prototype implementation was made from a common computer by the LabVIEW software through some independent modules for each disturbance to be measured. The numerical results of executed simulations of each disturbance generating comparisons between applied values and measured values are presented as tables within their percentage error for each phenomenon of each module.
67

Efeito do ultrassom na extra??o e caracter?sticas do amido de car?-do-ar (Dioscorea bulbifera) / Effect Ultrasound on extraction and starch characteristics of yam (Dioscorea bulbifera)

Bernardo, Cristiany Oliveira 26 February 2016 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-10-13T11:27:52Z No. of bitstreams: 1 2011 - Cristiany Oliveira Bernardo.pdf: 1740458 bytes, checksum: ae55b89b5f70448972ad5987c95450b1 (MD5) / Made available in DSpace on 2016-10-13T11:27:52Z (GMT). No. of bitstreams: 1 2011 - Cristiany Oliveira Bernardo.pdf: 1740458 bytes, checksum: ae55b89b5f70448972ad5987c95450b1 (MD5) Previous issue date: 2016-02-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Among the different possibilities of use in the food industry, ultrasound can be considered an alternative to substitute or reduce the use of chemicals in extraction processes or modification of starches. When used in the extraction, enables higher purity of the obtained starch. The starch-the-air yam has physical characteristics desirable for applications such as thickening agent or disintegrating tablet formulations, for example, however, this extraction is hindered by the presence starch mucilage this tubercle. The aim of this study was to review the effect of ultrasound on the extraction and modification of several starches, evaluate their use in starch extraction of yam and its impact on characteristics this starch. After evaluating the chemical composition of tubers, previously washed, peeled and crushed in a blender. Then the crushed sample subjected to ultrasound. Different times (3, 6 to 9 minutes) and amplitudes (12, 40 and 68%) were evaluated by the Box Benker experimental design, furthermore evaluated the control treatment (0% amplitude) and ?T6? (15 minutes, 70% amplitude), totaling 7 treatments (T1, T2, T3, T4, T5, T6 and control). After sonication, the suspension was filtered and the extraction continued by successive washings, centrifugation and drying in an oven. After evaluating the performance of the extraction, the different treatments were characterized by analysis of chemical composition, instrumental analysis of color, scanning electron microscopy, optical microscopy, particle size, pattern of crystallinity, swelling power and solubility, paste clarity, paste properties and thermal properties and absolute density. There was increase in yield of 29,85% (control) to 32,09%, when used longer time and amplitude (15 min and 70% amplitude). The ultrasound caused damage to the surface of starch and reduced starch crystallinity peak, characterized as type B. Additionally, increased swelling power and consequently the paste viscosity of some treatments. However, 15 minutes, 70% amplitude (T6), reduced the swelling power, the paste viscosity and paste clarity and increased the setback. Therefore, despite the small increase in yield, when used ultrasound during extraction, damage was caused in the structure of starch, as well as changes in its physical and chemical characteristics / Dentre as diferentes possibilidades de utiliza??o na ind?stria de alimentos, o ultrassom pode ser considerado uma alternativa para substituir ou reduzir a utiliza??o de subst?ncias qu?micas em processos de extra??o ou modifica??o de amidos. Quando utilizado na extra??o, possibilita maior pureza do amido obtido. O amido de car?-do-ar possui caracter?sticas f?sicas desej?veis para aplica??es como agente espessante ou desintegrante em formula??es de comprimidos, por exemplo. No entanto, a extra??o desse amido ? dificultada pela presen?a de mucilagem nesse tub?rculo. O objetivo do presente estudo foi revisar o efeito do ultrassom na extra??o e modifica??o de diversos amidos, como milho, arroz, mandioca, batata, entre outros, avaliar sua utiliza??o na extra??o do amido de car?-do-ar e seu impacto sobre as caracter?sticas desse amido. Ap?s avaliar a composi??o centesimal do car?-do-ar, o mesmo foi lavado, descascados e triturados em liquidificador. Em seguida a amostra triturada foi submetida ao ultrassom. Diferentes tempos (3, 6 e 9 minutos) e amplitudes (12, 40 e 68%) foram avaliados por meio do planejamento experimental Box Benker. Al?m desses foram avaliados os tratamentos controle (0% amplitude) e T6 (15 minutos, 70% amplitude), totalizando 7 tratamentos (T1, T2, T3, T4, T5, T6 e controle). A extra??o prosseguiu por meio de filtra??o, lavagens sucessivas, centrifuga??o e secagem em estufa. Ap?s avaliar o rendimento da extra??o, os diferentes tratamentos foram caracterizados por meio das an?lises de composi??o centesimal, an?lise instrumental de cor, poder de inchamento e solubilidade, claridade de pasta, determina??o das propriedades t?rmicas e propriedades de pasta, padr?o de cristalinidade, microscopia eletr?nica de varredura, microscopia ?ptica, determina??o do tamanho de part?cula e densidade absoluta do amido. Houve aumento do rendimento de 29,85% (controle) para 32,09%, quando utilizado o maior tempo e amplitude (15 min e 70% amplitude). O ultrassom provocou danos na superf?cie do amido e reduziu os picos de cristalinidade do amido, caracterizados como tipo B. Al?m disso, aumentou o poder de inchamento e consequentemente a viscosidade de pasta de alguns tratamentos. No entanto, 15 minutos e 70% de amplitude (T6), do tratamento com ultrassom, reduziu o poder de inchamento, a viscosidade de pasta e a claridade de pasta e aumentou a tend?ncia ? retrograda??o. Dessa forma, apesar do pequeno aumento do rendimento quando utilizado o ultrassom durante a extra??o, danos foram provocados na estrutura desse amido, assim como altera??es das suas caracter?sticas f?sico-qu?micas.
68

Analisador de redes WirelessHART com capacidade de detecção de coexistência

Machado, Tatiane Martins January 2014 (has links)
O uso de redes sem fio no ambiente industrial está crescendo cada vez mais devido às vantagens que estas redes apresentam comparadas aos sistemas cabeados. No entanto, é necessário que as redes sem fio apresentem a mesma robustez que as redes cabeadas. Para isso, é necessário garantir o enlace de rádio frequência entre os dispositivos e também é preciso que a rede atenda aos requisitos de comunicação em tempo real. O protocolo WirelessHART foi criado em 2007, sendo o primeiro padrão aberto de comunicação sem fio especialmente desenvolvido para ambientes industriais. Esse protocolo vem ganhando cada vez mais aplicabilidade na indústria devido à sua alta confiabilidade e robustez. Por se tratar de um protocolo recente, ainda existem muitas pesquisas em andamento, sendo uma das áreas relacionada a ferramentas para análise e monitoramento da rede. Tais ferramentas têm como objetivo principal capturar as mensagens que trafegam na rede, ou seja, atuam como um sniffer. No entanto, o protocolo WirelessHART apresenta algumas peculiaridades quando comparado a outras redes sem fio, como por exemplo, o uso de 15 canais diferentes. Devido a isso, muitos sniffers já propostos para redes sem fio não podem ser utilizados, pois capturam dados em apenas uma frequência. Outra questão está relacionada ao monitoramento de redes já instaladas, onde os dispositivos podem se encontrar em locais de difícil acesso. Dessa forma, é necessário que a ferramenta tenha mobilidade, ou seja, não necessite estar conectada a um computador, por exemplo. Então, uma vez que ainda não existe uma ferramenta de monitoramento ideal para redes WirelessHART, este trabalho propõe um nova ferramenta, que apresenta vantagens, tais como: captura de dados nos 15 canais utilizando apenas um receptor de rádio, armazenamento local dos dados capturados utilizando um cartão de memória e medição da energia nos canais, para obter informações a respeito de interferências na rede. Além disso, uma aplicação offline de análise dos dados apresenta estatísticas e análises a respeito dos dados capturados. Este trabalho apresenta alguns conceitos teóricos importantes a respeito do protocolo e os detalhes da implementação da ferramenta. Os resultados obtidos mostram que a ferramenta está atuando corretamente como um sniffer e está realizando a detecção de interferências na rede. Um estudo de caso mostra o comportamento da rede WirelessHART coexistindo com o padrão IEEE 802.11. / The use of wireless networks in industrial environment is growing due to the advantages of these networks compared to wired systems. However, the wireless networks must have the same robustness that wired networks. It is necessary to ensure the link between devices and it is also necessary that the network meets the requirements of real-time communication. The WirelessHART protocol was created in 2007, and it is the first open wireless communication standard specifically designed for industrial environments. This protocol has been gaining increasing applicability in industry due to its high reliability and robustness. Because it is a recent protocol, there are still many ongoing researches. One of them is related to tools for analyzing and monitoring the network. Such tools have the main objective to capture the messages that travel on the network, acting as a sniffer. However, the WirelessHART protocol has some peculiarities as compared to other wireless networks, such as the use of 15 different channels. Because of this, many sniffers already proposed for wireless networks can not be applied, because they capture data on only one frequency. Another issue is related to the monitoring networks already installed, where devices can be found in places of difficult access. Thus, it is necessary that the tool has mobility, i.e., does not need to be connected to a computer, for example. So, since there is still no ideal monitoring tool for WirelessHART networks, this paper proposes a new tool, which has advantages such as: data capture in 15 channels using only one radio receiver, local storage of captured data using a memory card and measuring the energy in the channels for getting information about interference in the network. In addition, an offline application presents statistics and analysis about the captured data. This paper presents some important theoretical concepts about the protocol and implementation details of the tool. The results show that the tool is working properly as a sniffer and it’s performing the interference detection in the network . A case study shows the behavior of the WirelessHART network coexisting with IEEE 802.11 standard.
69

Using Source-to-Source Transformations to Add Debug Observability to HLS-Synthesized Circuits

Monson, Joshua Scott 01 March 2016 (has links)
This dissertation introduces a novel approach for exposing the internal, source-level expressions of circuits generated by high-level synthesis (HLS) for in-circuit debug. The approach uses source-to-source transformations to instrument specific source-level expressions with debug ports. These debug ports allow a user to connect a debugging instrument (e.g. an embedded logic analyzer) to record the activity of the expression corresponding to the debug port. This dissertation demonstrates that a debugging solution based on these source-to-source transformations is feasible and that individual debug ports can be added for a cost of a 1-2% increase in circuit area on average. It also introduces another transformation that permits pointer-valued expressions to be instrumented for debug. It is demonstrated that all pointers in the CHStone benchmarks can be instrumented for an average 4% increase in circuit area. The debug port transformations are demonstrated on two HLS tools – Vivado HLS and Legup. The architecture of the source-to-source compiler allowed the necessary adaptations for the second tool (Legup) to be implemented using a minimal amount of additional code. Due to limitations in the Legup compiler an additional optimization was added to reduce the latency overhead incurred by the debug ports. User manuals and other documentation from 10 additional C-based HLS tools is examined to determine whether they are amenable to debug instrumentation using the source-to-source transformations. Of the 10 additional HLS tools examined, 6 were amenable to the transformations, 3 were likely to be amenable, and 1 was not. This dissertation estimates the cost of a complete debugging solution (i.e. one with debug ports and a debugging instrument) and identifies a possible worst case bound for adding debug ports. Finally, this dissertation analyzes two different debugging instruments and determines which instrument would be best for most HLS circuit mapped to FPGAs. It then estimates the overhead of this debugging solution.
70

Excitation du 201 Hg dans les plasmas produits par laser / 201 Hg excitation in plasma produced by laser

Comet, Maxime 09 December 2014 (has links)
L'utilisation des lasers de puissance permet l'étude des propriétés de la matière dans des conditions extrêmes de température et de densité. En effet, l'interaction d'un laser de puissance sur une cible créée un plasma dont la température est suffisamment grande pour atteindre des degrés d'ionisation élevés. Ces conditions peuvent permettre, via divers processus, d'exciter le noyau dans un état nucléaire et notamment dans un état isomère. Un noyau d'intérêt pour étudier ces phénomènes est le 201 Hg. Ce travail de thèse s'inscrit dans le cadre du dimensionnement d'une expérience visant la mise en évidence de l'excitation du 201 Hg dans un plasma laser.La première partie de ce manuscrit présente la détermination des taux d'excitation nucléaire dans les plasmas. Depuis une dizaine d'années les taux d'excitation sont déterminés en utilisant le modèle de l'atome moyen. Afin de valider ce modèle, un code, appelé ADAM (Au-Delà de l'Atome Moyen), a été développé afin de calculer le taux d'excitation nucléaire en DCA (Detailed Conguration Accounting). Il nous permettra d'en déduire un domaine thermodynamique en température et densité où les taux d'excitation déterminés avec le modèle de l'atome moyen sont pertinents.La deuxième partie présente le couplage des taux d'excitation nucléaire avec un code hydrodynamique afin d'en déduire, pour différentes intensités laser, le nombre de noyaux qu'il serait possible d'exciter par tir laser. Enfin, dans une dernière partie,les premières approches expérimentales qui serviront au dimensionnement d'une expérience sur une installation laser sont présentées. Ces approches sont basées sur la détection et la détermination de la quantité d'ions multichargés obtenue loin de la cible (~80 cm). Pour cela, un déviateur électrostatique a été utilisé. / The use of high power lasers allows the study of the properties of matter in extremeconditions of temperature and density. Indeed, the interaction of a power laser and atarget creates a plasma in which the temperature is high enough to reach important degrees of ionization. These conditions can allow the excitation of the nucleus. Anucleus of interest to study the processes of nuclear excitation is the 201 Hg. Thiswork aims to design an experiment where the 201 Hg excitation will be observed in aplasma produced by a high power laser. The first part of this manuscript presents the calculation of the expected nuclear excitation rates in the plasma. For about ten years, nuclear excitation rates have been calculated using the average atom model. To validate this model a code named ADAM (french acronym for Beyond The Average Atom Model) was developed to calculate the nuclear excitation rates under the DCA (Detailed Configuration Accounting) hypothesis. ADAM allows us to deduce the thermo dynamical domain where the nuclear excitation rates determined with the average atom model are relevant. The second part of this manuscript presents the coupling of the excitation rate calculation with a hydrodynamic code to calculate the number of excited nuclei produced in one laser shot for different laser intensity. Finally, in the last part, first experimental approaches which will be used to design an experiment on a laser installation are presented. These approaches are based on the detection and determination of the amount of multicharged ions obtained far from the target (~80 cm). For this purpose, an electrostatic analyzer was used.

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