Dissertations / Theses: 'Pulse diagnosis'

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Smith, Andrew, and n/a. "Pulse diagnosis in traditional acupuncture." University of Canberra. Education, 1993. http://erl.canberra.edu.au./public/adt-AUC20061109.082650.

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The process of pulse diagnosis was examined in a sample of 100 patients randomly selected from the author's acupuncture clinic. Patient symptoms, pulses (as utilised in traditional Chinese medicine), diagnostic criteria (as described in traditional Chinese medicine), acupuncture points selected and patient comments after each treatment were coded into a numerical format suitable for stepwise multiple regression and crosstabulation analysis. The analysis indicated that the interpretation of pulse qualities predicted the diagnostic criteria when used in accordance with the theories of acupuncture. The selection of acupuncture points could not be predicted from the diagnostic criteria when using pulse diagnosis. Additionally the analysis indicated that the patient comments after acupuncture were independent of the initial patient symptoms. More research is needed to more fully understand the process of pulse diagnosis. However the analysis does suggest that pulse diagnosis should be incorporated into acupuncture curricula in both traditional acupuncture courses and medical acupuncture courses.

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Nyman, David. "Injector diagnosis based on engine angular velocity pulse pattern recognition." Thesis, Uppsala universitet, Signaler och system, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-414967.

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In a modern diesel engine, a fuel injector is a vital component. The injectors control the fuel dosing into the combustion chambers. The accuracy in the fuel dosing is very important as inaccuracies have negative effects on engine out emissions and the controllability. Because of this, a diagnosis that can classify the conditions of the injectors with good accuracy is highly desired. A signal that contains information about the injectors condition, is the engine angular velocity. In this thesis, the classification performance of six common machine learning methods is evaluated. The input to the methods is the engine angular velocity. In addition to the classification performance, also the computational cost of the methods, in a deployed state, is analysed. The methods are evaluated on data from a Scania truck that has been run just like any similar commercial vehicle. The six methods evaluated are: logistic regression, kernel logistic regression, linear discriminant analysis, quadratic discriminant analysis, fully connected neural networks and, convolutional neural networks. The results show that the neural networks achieve the best classification performance. Furthermore, the neural networks also achieve the best classification performance from a, in a deployed state, computational cost effectiveness perspective. Results also indicate that the neural networks can avoid false alarms and maintain high sensitivity.

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Insall, R. L. "Pulse waveforms and transit time from photoelectric plethysmography in the diagnosis of peripheral vascular disease." Thesis, University of Newcastle Upon Tyne, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309069.

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4

Kataoka, Simony Hidee Hamoy. "A oximetria de pulso como recurso na determinação da vitalidade pulpar em pacientes submetidos à radioterapia para tumores malignos intraorais e de orofaringe." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/23/23145/tde-18082010-121032/.

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O objetivo deste trabalho foi avaliar a taxa de oxigenação (%SpO2) do tecido pulpar em pacientes com tumores malignos intraoral e de orofaringe, tratados através de radioterapia (RT). As mensurações da %SpO2 foram realizadas com o oxímetro de pulso (OP), o qual gera valores relativos à quantidade de oxigênio viável circulante no tecido pulpar, o que o caracteriza como um método fisiométrico de avaliação do status da polpa dental. Foram selecionados 20 pacientes, sendo avaliados dois dentes de cada um (n=40), independente do quadrante e da área de irradiação, em quatro tempos distintos: I- antes da RT; II- no início da RT com dose de radiação entre (30Gy 35Gy); III- ao final da RT (60Gy 70Gy) e IV- depois de 4 5 meses do início do tratamento oncológico. As médias obtidas nos quatro tempos avaliados foram de 93%, 83%, 77% e 85% de SpO2, respectivamente. Através do teste t de Student (p0.01) foram encontradas diferenças estatisticamente significantes entre o Tempo I e todos os outros três tempos, o Tempo III também mostrou diferença quando comparado ao Tempo II e, não houve diferença estatística entre os Tempos II e IV. É possível concluir que as taxas de %SpO2 antes da RT são maiores do que aquelas obtidas trans e pós RT e, como os valores no Tempo IV ficam próximos aos obtidos no Tempo II, pode haver uma recondutibilidade sanguínea normal posterior a radiação ionizante.
The aim of this study was to evaluate pulp oxygenation level (%SpO2) in patients with malignant intraoral and oropharyngeal tumors treated by radiotherapy (RT). Pulp oxygenation level was measured by pulse oximetry, which shows the amount of oxygen circulating in viable pulp tissue and is a physiometric method for assessment of dental pulp status. Twenty patients were selected and two teeth of each of them (n = 40) were analyzed, regardless of the quadrant and the area irradiated, at four different times: I- before RT; IIat the beginning of RT with radiation doses between 30Gy 35Gy; III- at the end of RT (60Gy 70Gy) and IV- after 4-5 months of the beginning of the cancer treatment. Mean %SpO2 in the different times was 93%, 83%, 77% and 85%, respectively. Students t test (p0.01) showed statistically significant differences between Time I and the other three times. Time III was also different when compared to Time II, and there was no statistical difference between Times II and IV. It was concluded that %SpO2 before RT was greater than that observed during and after therapy and, as values obtained in Time IV were close to those of Time II, pulp tissue may show normal blood flow after radiation therapy.

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Nicoll, Deborah J. "Prospective evaluation of pulse transit time in the diagnosis and management of the obstructive sleep apnoea/hypopnoea syndrome." Thesis, Oxford Brookes University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302448.

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Yang, Yingying. "Innovative non-destructive methodology for energy diagnosis of building envelope." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0913/document.

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Le secteur du bâtiment représente 35% des la consommations énergétiques dans les pays membres de l’agence international de l’énergie en 2010 et 39,8% aux Etats-Unis en 2015. Plus de 50% de cette consommation a été utilisée pour la production de chaleur et de froid. Néanmoins cette consommation peut être réduite par l'amélioration la performance énergétique du bâtiment. La performance thermique de l'enveloppe du bâtiment joue un rôle primordial. Par conséquent, le diagnostic thermique de l'enveloppe du bâtiment est nécessaire pour, par exemple, la réception de nouvelles constructions, l'amélioration de la performance énergétique des anciens bâtiments, ainsi que la vente et la location des logements. Pourtant, il existe très peu de méthodes quantitatives pour la caractérisation des parois épaisses. L'objectif de cette étude est d'explorer des méthodes quantitatives innovantes de diagnostic thermique de l'enveloppe du bâtiment. Des mesures expérimentales ont été réalisées en laboratoire (à l’IFSTTAR à Nantes) et in situ (à l’IUT de Bordeaux). Différents capteurs et méthodes d'instrumentation ont été étudiés pour mesurer la densité de flux et la température de surfaces des parois, afin de procurer des recommandations pour le choix des capteurs ainsi que des protocoles de traitement de données. A partir des données mesurées (température et densité de flux des surfaces de l'enveloppe), trois approches numériques ont été proposées pour estimer des paramètres thermiques des parois multicouches épaisses : par méthode inverse, par réponse à un échelon et par réponse impulsionnelle. En outre, une méthode innovante non-destructive utilisant la rayonnement térahertz a été étudiée. Les mesures ont été effectuées au sein du laboratoire I2M. Cette méthode permet de caractériser le coefficient d'absorption des matériaux constructifs ordinaires comme isolation, plâtre, béton, bois… Elle pourrait postérieurement être combinée avec une méthode thermique pour apporter des informations complémentaires
Buildings represent a large share in terms of energy consumption, such as 35% in the member countries of IEA (2010) and 39.8% in U.S. (2015). Climate controlling (space heating and space cooling) occupies more than half of the consumption. While this consumption can be reduced by improving the building energy efficiency, in which the thermal performance of building envelope plays a critical role. Therefore, the thermal diagnosis of building envelope is of great important, for example, in the case of new building accreditation, retrofitting energy efficiency of old building and the building resale and renting. However, very few diagnostic methods exist for the characterization of thick walls. The present measurement standards that based on steady state heat transfer regime need a long time (several days). The classical transient technologies, such as flash method, are difficult to implement on the walls because of the large thickness of walls and the complex conditions in situ. This thesis aims to explore innovative methodologies for thermal quantitative diagnosis of building envelope. Two experimental cases were carried out: one is in laboratory (IFSTTAR, Nantes) and the other is in situ (IUT, Bordeaux). Different sensors and instruments were studied to measure the wall heat flux and surface temperature, and provided some guidelines for the choice of sensors and data processing protocols as well. Using these measured data, three estimation approaches were proposed to estimate the thermal parameters of the multilayer thick wall: pulse response curve method, step response curve method and inverse method, which can be applied for different diagnostic situations. In addition, an innovative NDE (non-destructive evaluation) method using terahertz (THz) radiation was also investigated. Measurements were carried out in I2M laboratory to characterize the absorption coefficient of standard building materials (insulation, plaster, concrete, wood ...). This THz method can be combined with a previous thermal method to provide some complementary information

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Júnior, Roberto Castro. "Glicosímetro de pulso." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/3/3142/tde-16082010-161914/.

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Este trabalho descreve o desenvolvimento e a avaliação clínica de um instrumento para monitorização contínua e não-invasiva da concentração de glicose no sangue arterial adotando o mesmo método que a oximetria de pulso utiliza para determinação da saturação do sangue arterial. O sistema para medição de glicemia de pulso desenvolvido neste trabalho foi projetado a partir da utilização de um sensor óptico similar aos sensores de oximetria de pulso utilizando os comprimentos de onda de 805 e 1350 nm. Foi realizada uma avaliação clínica do instrumento com 20 voluntários masculinos e femininos entre 16 e 63 anos, de 48 a 112 kg e diferentes raças. Para estes voluntários, o instrumento apresentou uma exatidão (Arms) e desvio padrão (SDR) da ordem de 10 mg/dl, que podem ser considerados muito bons, quando comparado com monitores de glicemia do tipo ponta de dedo, que apresentam uma exatidão da leitura da ordem de 15 mg/dl para a faixa de medidas utilizada.
This paper describes the development and the clinical evaluation of a continuous non-invasive monitoring device for blood glucose concentration in arterial blood. The adopted method was the same one used in pulse oximetry for determining arterial blood saturation. The measurement system developed in this project to determine pulse blood glucose level was based on an optical sensor similar to the pulse oximetry sensors using wavelengths of 805 and 1350 nm. A clinical trial of the device was performed with 20 volunteers, both male and female, aged 16 to 63, weighting 48 to 112 kg and of different races. For this group of volunteers the device presented an accuracy (Arms) e standard deviation (SDR) in the magnitude of 10 mg/dl, considered very good when compared to blood glucose monitors of the fingertip type, which presents a reading accuracy in the magnitude of 15 mg/dl for the range of measurements employed.

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West, Ian Philip. "Optical fibre based pulse oximetry." Thesis, University of Liverpool, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262607.

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Neto, Nilton Salles Rosa. "Avaliação não invasiva das propriedades estruturais de grandes artérias em pacientes com arterite de Takayasu." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/5/5164/tde-16092013-151428/.

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A Arterite de Takayasu (AT) é uma vasculite granulomatosa de aorta e grandes vasos associada a elevado risco cardiovascular. A velocidade de onda de pulso (VOP) é um método de avaliação indireta de diminuição da distensibilidade arterial, e valores elevados de VOP correlacionam-se com maior morbimortalidade cardiovascular. A avaliação da VOP em pacientes com arterite de Takayasu é complexa devido a muitos fatores de confusão. O objetivo do presente estudo foi avaliar a rigidez arterial, por meio da velocidade de onda de pulso carótido-femoral (VOP-CF) em pacientes do sexo feminino com arterite de Takayasu e controles saudáveis com variáveis clínicas e antropométricas comparáveis, e sua possível associação com os parâmetros da doença. Método: Pacientes com arterite de Takayasu (n = 27) foram avaliados consecutivamente e foram selecionados controles saudáveis com idade, pressão arterial, peso e altura comparáveis (n = 27). Os critérios de exclusão foram menopausa, tabagismo, diabetes, insuficiência renal, hipertensão mal controlada, arritmias cardíacas, obesidade, comorbidades inflamatórias, gravidez e história de procedimentos cirúrgicos que envolvessem a aorta. A atividade da doença foi determinada por parâmetros clínicos e laboratoriais. As medições de VOP-CF foram obtidas pelo Sistema Complior. Resultados: A média de VOP-CF foi maior em pacientes com arterite de Takayasu do que em controles (9,77 ± 3,49 vs. 7,83 ± 1.06 m/s, p = 0,009). Apesar dos rigorosos xv critérios de seleção, os pacientes com arterite de Takayasu ainda apresentavam, em média, pressão arterial sistólica de 8 mmHg maior do que os controles (p > 0,05), e os valores de pressão de pulso significativamente mais elevados. O modelo de regressão linear múltipla mostra que 93,8% da variabilidade da VOP é explicada pelas variáveis idade, pressão arterial média (PAM) e pela própria doença (R2 ajustado = 0,938). A análise logística stepwise usando como variável dependente o valor de corte de VOP estabelecido pela curva ROC (> 8,34 m/s) e, como variáveis independentes, os parâmetros com significância na análise univariada, revelou que arterite de Takayasu (OR: 4,69, IC 95% 1,31 - 16,72; p = 0,017) e PAM (OR: 1,06, IC 95% 1,00 - 1,12, p = 0,048) foram independentemente associados a maior VOP. Uma análise mais aprofundada dos parâmetros de doença revelou que os valores de VOP não foram correlacionados com velocidade de hemossedimentação, proteína C-reativa, dose cumulativa de glicocorticoides e fração de ejeção (p > 0,05). Conclusão: Nesta coorte de pacientes do sexo feminino com arterite de Takayasu, a própria doença e a pressão arterial média foram os determinantes mais fortemente associados com elevada rigidez arterial e não houve correlação dos valores de VOP com parâmetros de atividade da doença
Takayasu arteritis (TA) is a granulomatous vasculitis that affects the aorta and large vessels and is associated with higher cardiovascular risk. Pulse wave velocity (PWV) is a method of indirect evaluation of decreased arterial distensibility, and elevated PWV correlates with increased cardiovascular morbidity and mortality. The assessment of PWV in patients with Takayasu arteritis is complex due to many confounding factors. The aim of this study was to evaluate arterial stiffness, assessed by carotid-femoral pulse wave velocity (CF-PWV) in female patients with TA and healthy controls with comparable anthropometric and clinical variables, and the possible association with parameters of the disease. Method: Patients with TA (n = 27) were consecutively evaluated and healthy controls were selected with comparable age, blood pressure, weight and height (n = 27). Exclusion criteria were menopause, smoking, diabetes, renal insufficiency, poorly controlled hypertension, cardiac arrhythmias, obesity, inflammatory comorbidities, pregnancy and history of surgical procedures involving the aorta. Disease activity was determined by clinical and laboratory parameters. The CF-PWV measurements were obtained by the Complior System. Results: The mean CF-PWV was higher in patients with TA than in controls (9.77 ± 3.49 vs. 7.83 ± 6.1 m / s, p = 0.009). Despite the strict selection criteria, TA patients still had, on average, systolic blood pressure of 8 mmHg greater than controls (p > 0.05), and pulse pressure values significantly higher. The multiple linear regression model showed that 93.8% of the variability in PWV is explained by the variables age, mean arterial pressure (MAP) and the disease itself (adjusted R2 = 0.938). A stepwise logistic analysis using as the dependent variable the cutoff value of VOP established by the ROC curve (> 8.34 m/s) and, as independent variables, parameters with significance in the univariate analysis, revealed that Takayasu arteritis (OR: 4.69 95% CI 1.31 - 16.72, p = 0.017) and MAP (OR: 1.06, 95% CI 1.00 - 1.12, p = 0.048) were independently associated with increased PWV. Further analysis of disease parameters revealed that PWV values were not correlated with erythrocyte sedimentation rate, C-reactive protein, cumulative dose of glucocorticoids or ejection fraction (p > 0.05). Conclusion: In this cohort of female patients with Takayasu arteritis, the disease itself and mean arterial pressure were determinants most strongly associated with elevated arterial stiffness and no correlation of PWV values and parameters of disease activity was found

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Clarke, Gregory Charles Bernard. "Diagnostic study of the pulsed magnetron." Thesis, Manchester Metropolitan University, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.441640.

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Billinge, Emily R. "Aptasensors using tunable resistive pulse sensing." Thesis, Loughborough University, 2016. https://dspace.lboro.ac.uk/2134/21468.

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In recent years there has been an increased drive towards point of care testing (POCT), in which assays are performed at the site of the patient. This has many benefits, critically; the time for a result to be obtained will be significantly reduced, allowing for greater and more effective decision making. Many currently used bioassay methods are not affordable in resource poor areas where infectious disease is most prevalent, in order to combat this issue many research groups are attempting to miniaturise equipment for portability and make assays more affordable and therefore more accessible. With the aims of generating a new assay platform which is highly portable and affordable, the work in this thesis presents the development of several generic methods utilising nano- and micro-scale beads coated with aptamer which are then monitored interacting with target proteins with Tunable Resistive Pulse Sensing (TRPS). Aptamers are short oligonucleotide sequences which are capable of binding to a wide range of targets with high selectivity and comparable affinity to antibodies while possessing greater stability and have begun to challenge the role of antibodies. When aptamers bind a target, they often undergo a conformational change. In the assays described herein, this conformational change is key to the observed signal changes. TRPS is a pore-based system in which beads moving through a pore cause a measurable increase in resistance which can be used to derive particle size, concentration, and mobility. During the course of this thesis several template TRPS aptasensors have been developed. TRPS was successfully used to confirm the successful coating of nano- and micro-scale beads with DNA aptamers by monitoring an increase in electrophoretic mobility when the negatively charged DNA is added to the surface. Following on from this, TRPS was used to monitor the interaction of aptamer tagged beads with thrombin protein enabling thrombin detection down to 1.4 nM and the comparison of several thrombin-aptamers with results comparable to previously published SPR data. Thrombin was postulated to shield the negative DNA, resulting in a decrease in mobility, and the magnitude of this charge shielding was found to depend upon the binding mechanism of the aptamer used. This effect is not thought to be specific to our system nor to thrombin, the principles outlined here may be applied to other RPS technologies, or by interchanging of the aptamer, different proteins. In later chapters, this method is expanded to include multiplexed detection of growth factors and a significant improvement in signal. vi Following on from this, the controlled aggregation of avidin coated beads in the presence of biotinylated-BSA was explored. Factors impacting upon this assay were discussed including magnetic separation, particle size and particle concentration, and different methods of data interpretation were presented. This aggregation study identified several key parameters in the use of TRPS in aggregation assays. Using the methods outlined by the study of aggregates, a dispersion assay was then designed in which the interaction of thrombin proteins with clusters of particles brought about the release of many small particles by the disruption of double stranded DNA linkages. This dispersion assay incorporated magnetic separation to simplify the read-out and relied on measuring particle concentration rather than mobility, enabling the use of additional pressure to increase speed and ease of use. Using this method, thrombin was able to be detected down to 100 fM, a significant advancement in TRPS aptasensors.

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Valetin, Antonio. "Single pulse stimulation in human symptomatic epilepsy : New diagnostic tool." Thesis, King's College London (University of London), 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.498219.

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Austin, Dane R. "High-resolution interferometric diagnostics for ultrashort pulses." Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:03ff32ea-c82a-4a42-9c6b-11e42ddb1e67.

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I present several new methods for the characterisation of ultrashort pulses using interferometry. A generalisation of the concatenation algorithm for spectral shearing interferometry enables interferograms taken at multiple shears to be combined. This improves the precision of the reconstructed phase in the presence of detector noise, and enables the relative phase between disjoint spectral components to be obtained without decreasing the spectral resolution. The algorithm is applied to experimental data from two different implementations of spectral shearing interferometry for ultrashort optical pulses. In one, the shears are acquired sequentially, and in the other they are acquired simultaneously. I develop a form of spatio-temporal ultrashort pulse characterisation which performs both spatial and spectral shearing interferometry simultaneously. It requires a similar geometrical setup to common implementations of spectral phase interferometry for direct electric-field reconstruction, but provides complete amplitude and phase characterisation in time and one spatial dimension. I develop the theory of lateral shearing interferometry for spectrally resolved wavefront sensing of extended ultraviolet and soft x-ray pulses generated using high-harmonic generation. A comprehensive set of wavefront measurements of harmonics 13-25 in Krypton show good agreement with theory, validating the technique. I propose and numerically demonstrate quantum-path interferometry mediated by a weak control field for high harmonic generation. This is a general technique for measuring the amplitude and relative phases of each contributing quantum path. The control field perturbatively modulates the phase of each path. The differing sensitivity of each path to the parameters of the control field allows their contributions to be distinguished from one another.

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Schrijvers, Coen. "Spectroscopic diagnostics of pulsation in rotating stars." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 1999. http://dare.uva.nl/document/92629.

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Kemp-Harper, Richard Owen. "Development of multiple-pulse NMR methods for investigation of sodium ions in vitro." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339303.

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Roberts, Timothy Paul Leslie. "Radiofrequency pulse design for use in nuclear magnetic resonance imaging and localized spectroscopy." Thesis, University of Cambridge, 1992. https://www.repository.cam.ac.uk/handle/1810/283680.

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Mahdieh, Mohammad Hossain. "Optical diagnosis of shock waves driven by high power laser pulses." Thesis, University of Essex, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307858.

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Harris, Steven Scott. "Adiabatic pulse preparation for imaging iron oxide nanoparticles." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/47555.

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Iron oxide nanoparticles are of great interest as contrast agents for research and potentially clinical molecular magnetic resonance imaging (MRI). Biochemically modifying the surface coatings of the particles with proteins and polysaccharides enhances their utility by improving cell receptor specificity, increasing uptake for cell labeling and adding therapeutic molecules. Together with the high contrast they produce in MR images, these characteristics promise an expanding role for iron oxide nanoparticles and molecular MR imaging for studying, diagnosing and treating diseases at the molecular level. However, these contrast agents produce areas of signal loss with traditional MRI sequences that are not specific to the nanoparticles and cannot easily quantify the contrast agent concentration. With the expanding role of iron oxide nanoparticles in molecular imaging, new methods are needed to produce a quantitative contrast that is specific to the iron oxide nanoparticle. This dissertation presents a new method for detecting and quantifying iron oxide nanoparticles using an adiabatic preparation pulse and the failure of the adiabatic condition for spins diffusing near the particles. In the first aim, the theoretical foundation of the work is presented, and a Monte Carlo simulation supporting the proposed mechanism of the contrast is described. Adiabatic pulse prepared imaging sequences are also developed for imaging at 3 Tesla and 9.4 Tesla to highlight the translational potential of the approach for clinical examinations and scientific research, and the linear correlation of the contrast with iron concentration ideal for quantification is presented. Further, the physical characteristics of the nanoparticles and the parameters of the MRI sequence are modified to characterize the approach. In the second aim, the contrast is characterized in more realistic phantoms and in vitro, and a method to more accurately quantify nanoparticle concentration in the presence of magnetization transfer is presented. Finally, accelerated imaging methods are implemented to acquire the adiabatic contrast in a time compatible with in vivo imaging, and the technique is evaluated in an in vivo model of quantitative iron oxide nanoparticle imaging. Together, these aims present a method using an adiabatic preparation pulse to generate an MR contrast based on the microscopic magnetic field gradients surrounding the iron oxide nanoparticles that is suitable for in vivo quantitative, molecular imaging.

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梁平 and Ping Maurice Leung. "The role of cross-sectional and pulsed Doppler echocardiography in themanagement of patients with congenital heart disease: a changing practice." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1991. http://hub.hku.hk/bib/B30408908.

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Hao, Liu. "Pulsed laser ablation and laser-induced plasma diagnosis by optical emission spectroscopy." Thesis, University of Bristol, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.702119.

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Fundamental aspects of the laser ablation of solid targets using nanosecond pulses with irradiances in the range ≈ 1-30 OW /cm2 have been investigated theoretically, modelled using a simulation code, and explored experimentally by time-gated, spatially and spectrally resolved imaging of the optical emission that accompanies the ablation plume. During the earliest stages of the laser-target interaction, the target surface temperature rises rapidly and electrons are ejected by both thermionic and photo-emission. These electrons absorb energy from the · laser pulse by strong electron-photon coupling, leading to formation of an embryonic plasma which continues to gain energy via photoionization and, particularly, inverse bremsstrahlung (IB) absorption. The target is further heated by the hot plasma and may reach temperatures of several thousand Kelvin, approaching its critical point, and undergo an explosive phase transition to the supercritical fluid. Such a super-hot target surface emits an abundance of electrons, neutrals and ions. The present work shows that the electron yield following 532 nm PLA of a Si target is significantly higher than that produced using 1064 nm pulses of same irradiance. The fastest electrons emerge at the leading edge of the plasma plume, creating an electric field gradient with respect to the net positively charged body of the plume. This has the effect of accelerating ions in the plume, to extents that ·depend on their charge state. Emissions from any given charge state show identical spatial distributions in the time-gated images. The most highly charged ions (e.g. SiIV ions in the case of PLA of Si in vacuum) exhibit velocities of ~ 1 00 km/s. Experiment and simulation show that plasma produced by 1064 nm excitation is hotter and expands faster than that formed by 532 nm PLA - a result that can be attributed to the stronger IB absorption of the longer wavelength radiation. A new and improved method for determining local electron densities (Ne) and temperatures (Te) in laser induced plasmas is introduced. The model relies on fitting Stark broadened line shapes but, in contrast to most rival approaches, makes no preassumption regarding local thermodynamic equilibrium. The method is used to determine temporally and spatially evolving Ne and Te distributions in plumes arising from PLA of Si and SiC targets, as functions of irradiance, excitation wavelength and ambient pressure. We also demonstrate how Ne and Te values determined by fitting lines associated with one spectral carrier allow derivation of (hitherto unknown) Stark parameters for transitions involving other carriers. A clear shock front is observed following PLA of Si in background Ar pressures ~0.2 Torr, even as early as 40 ns. Strong collisions between highly charged ions in the plume and the surround gas are seen to introduce another level of complexity (e.g. ionization, recombination, charge transfer, etc.) within and beyond the shock front in the plume.

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Yan, Xiaoling. "Ultra-fast photon and electron beam diagnostics for free electron lasers." Thesis, Abertay University, 2003. https://rke.abertay.ac.uk/en/studentTheses/4a05ee9c-2ddb-434f-b2a1-0ad483394db8.

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Characterisation of the ultra-short optical pulses produced by infrared ffee-electron lasers (FELs) is an important task, not only for the further development of free electron lasers and their theory, but also for their operation as a research tool. The setting up and optimisation of the FEL requires effective and reliable diagnostics tools. This thesis presents techniques for the measurement of sub-picosecond optical and electron pulses. A range of techniques is developed that allows measurements of the electric field of both optical pulses and electron bunches to be made with an accuracy of better than 100 fs. These techniques have been used to obtain the first complete electricfield characterisation of ultra-short pulses from a far-infrared FEL; to study the formation of singlesided exponential optical pulses in two FELs; and to obtain the longitudinal profile of electron bunches, both by probing the near-field transition radiation and by directly sensing the Coulomb field of the electron bunches. Although the techniques described are not truly single-shot - requiring measurements averaged over a period of a few microseconds - ways in which they could be extended to provide single-shot capability are discussed.

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Lade, Robert James. "Pulsed ultraviolet laser ablation of carbon containing targets." Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302156.

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Starritt, Hazel Catherine. "Streaming induced by high amplitude acoustic pulses and its implications." Thesis, University of Bath, 1990. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278251.

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Neidel, Tobias, Nicolas Salvador, and Axel R. Heller. "Impact of systolic blood pressure limits on the diagnostic value of triage algorithms." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-231546.

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Background Major incidents are characterized by a lack of resources compared to an overwhelming number of casualties, requiring a prioritization of medical treatment. Triage algorithms are an essential tool for prioritizing the urgency of treatment for patients, but the evidence to support one over another is very limited. We determined the influence of blood pressure limits on the diagnostic value of triage algorithms, considering if pulse should be palpated centrally or peripherally. Methods We used a database representing 500 consecutive HEMS patients. Each patient was allocated a triage category (T1/red, T2/yellow, T3/green) by a group of experienced doctors in disaster medicine, independent of any algorithm. mSTaRT, ASAV, Field Triage Score (FTS), Care Flight (CF), “Model Bavaria” and two Norwegian algorithms (Nor and TAS), all containing the question “Pulse palpable?”, were translated into Excel commands, calculating the triage category for each patient automatically. We used 5 blood pressure limits ranging from 130 to 60 mmHg to determine palpable pulse. The resulting triage categories were analyzed with respect to sensitivity, specificity and Youden Index (J) separately for trauma and non-trauma patients, and for all patients combined. Results For the entire population of patients within all triage algorithms the Youden Index (J) was highest for T1 (J between 0,14 and 0,62). Combining trauma and non-trauma patients, the highest J was obtained by ASAV (J = 0,62 at 60 mmHg). ASAV scored the highest within trauma patients (J = 0,87 at 60 mmHg), whereas Model Bavaria (J = 0,54 at 80 mmHg) reached highest amongst non-trauma patients. FTS performed worst for all patients (J = 0,14 at 60 mmHg), showing a lower score for trauma patients (J = 0,0 at 60 mmHg). Change of blood pressure limits resulted in different diagnostic values of all algorithms. Discussion We demonstrate that differing blood pressure limits have a remarkable impact on diagnostic values of triage algorithms. Further research is needed to determine the lowest blood pressure value that is possible to palpate at a peripheral artery compared to a central artery. Conclusion As a consequence, it might be important in which location pulses are palpated according to the algorithm at hand during triage of patients.

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Dooley, Patrick W. Corkum Paul B. "Molecular imaging using femtosecond laser pulses." *McMaster only, 2003.

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Fuller, Joseph P. "High-frame-rate planar laser-induced fluorescence imaging of diesel sprays using pulse burst diagnostics." [Ames, Iowa : Iowa State University], 2009.

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27

Logan, Richard. "Investigation of the effects of a pulsed electrode on a magnetized plasma." Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/15934.

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Neidel, Tobias, Nicolas Salvador, and Axel R. Heller. "Impact of systolic blood pressure limits on the diagnostic value of triage algorithms." BioMed Central, 2017. https://tud.qucosa.de/id/qucosa%3A30689.

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Background Major incidents are characterized by a lack of resources compared to an overwhelming number of casualties, requiring a prioritization of medical treatment. Triage algorithms are an essential tool for prioritizing the urgency of treatment for patients, but the evidence to support one over another is very limited. We determined the influence of blood pressure limits on the diagnostic value of triage algorithms, considering if pulse should be palpated centrally or peripherally. Methods We used a database representing 500 consecutive HEMS patients. Each patient was allocated a triage category (T1/red, T2/yellow, T3/green) by a group of experienced doctors in disaster medicine, independent of any algorithm. mSTaRT, ASAV, Field Triage Score (FTS), Care Flight (CF), “Model Bavaria” and two Norwegian algorithms (Nor and TAS), all containing the question “Pulse palpable?”, were translated into Excel commands, calculating the triage category for each patient automatically. We used 5 blood pressure limits ranging from 130 to 60 mmHg to determine palpable pulse. The resulting triage categories were analyzed with respect to sensitivity, specificity and Youden Index (J) separately for trauma and non-trauma patients, and for all patients combined. Results For the entire population of patients within all triage algorithms the Youden Index (J) was highest for T1 (J between 0,14 and 0,62). Combining trauma and non-trauma patients, the highest J was obtained by ASAV (J = 0,62 at 60 mmHg). ASAV scored the highest within trauma patients (J = 0,87 at 60 mmHg), whereas Model Bavaria (J = 0,54 at 80 mmHg) reached highest amongst non-trauma patients. FTS performed worst for all patients (J = 0,14 at 60 mmHg), showing a lower score for trauma patients (J = 0,0 at 60 mmHg). Change of blood pressure limits resulted in different diagnostic values of all algorithms. Discussion We demonstrate that differing blood pressure limits have a remarkable impact on diagnostic values of triage algorithms. Further research is needed to determine the lowest blood pressure value that is possible to palpate at a peripheral artery compared to a central artery. Conclusion As a consequence, it might be important in which location pulses are palpated according to the algorithm at hand during triage of patients.

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Ramos-Ortiz, Gabriel. "Frequency conversion in conjugated organic molecules and its applications to ultra-fast pulse diagnostic and imaging." Diss., The University of Arizona, 2003. http://hdl.handle.net/10150/289952.

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This dissertation is devoted to the study of third-harmonic generation (THG) in push-pull chromophore-doped polymer films. This kind of films, with amorphous structure, exhibit null second harmonic generation but strong THG when pumped at the fundamental wavelengths within the telecommunication range (1.4-1.6 μm). It is demonstrated that at 1550 nm, micrometer-thick samples generate up to 17 muW of green light with an input power of 250 mW delivered by an optical parametric oscillator. This high conversion efficiency is achieved without the use of phase matching or cascading of quadratic nonlinear effects and it is due to high values of the third-order nonlinear susceptibility combined with weak film absorption at the third harmonic wavelength. The efficient THG process opens the doors to low cost and sensitive third-order optical autocorrelation and cross-correlation applications. So, in addition to the basic research performed about the characterization of the THG in push-pull chromophore-doped polymer films, two applications are demonstrated. The first is the complete diagnostic of femtosecond pulses by THG-Interferometric Autocorrelation and by THG Frequency-Resolved Optical Gating. The second is the THG-Cross-correlation Time-Gated Imaging of objects embedded in highly scattering conditions.

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Campbell, Brian Thomas. "An evaluation of pulse-wave tissue Doppler echocardiography as a diagnostic tool in cardiac disease states." Thesis, University of Ulster, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.412128.

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Hugon, Robert. "Diagnostics d'un plasma pulse d'azote pour l'étude de sa réactivité : comparaison des résultats expérimentaux avec un modèle numérique." Nancy 1, 1994. http://www.theses.fr/1994NAN10427.

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Ce travail est consacré à l'étude de la réactivité d'un plasma pulse d'azote utilisé pour la nitruration des aciers. L'interprétation des mécanismes se produisant dans le plasma lui-même, et plus spécialement pendant la phase de post-décharge, nécessite un diagnostic finement résolu dans le temps. Pour les sondes électrostatiques, un dispositif automatique performant a été réalisé et permet la détermination expérimentale de la fonction de distribution en énergie des électrons et le suivi de son évolution sur un pulse plasma. La spectroscopie optique d'émission consiste en l'observation des bandes les plus intenses de l'azote et des raies d'atomes du fer pulvérisés par la cathode et excités dans le plasma. Une étude spatiale et temporelle de la structure axiale est comparée aux résultats issus d'une modélisation de l'établissement de la décharge. Enfin, après la mise en évidence de l'influence du chauffage du gaz neutre sur les paramètres de la décharge, des conditions favorables pour un traitement de surface par un plasma d'azote sont dégagées

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Miller, Paul Wesley. "The Utility of Total Lightning in Diagnosing Single-cell Thunderstorm Severity in the Central Appalachian Mountains Region." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/56976.

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Recent severe weather research has examined the potential role of total lightning patterns in the severe thunderstorm warning-decision process although none to-date have examined these patterns in explicitly weak-shear environments. Total lightning flashes detected by the Earth Networks Total Lightning Network (ENTLN) during the 2012-13 convective seasons (1 May – 31 August) over a region of the Central Appalachian Mountains were clustered into likely discrete thunderstorms and subsequently classified as either single-cell or multicell/supercell storm modes. The classification of storms was determined using a storm index (SI) which was informed by current National Weather Service (NWS) identification techniques. The 36 days meeting the minimum threshold of lightning activity were divided into 24 lightning-defined (LD) single-cell thunderstorm days and 12 LD multicell/supercell days. LD single-cell days possessed statistically significant lower 0000 UTC 0-6 km wind shear (13.8 knots) than LD multicell/supercell days (26.5 knots) consistent with traditional expectations of single-cell and multicell/supercell environments respectively. The popular 2σ total lightning jump algorithm was applied to all flashes associated with 470 individual LD thunderstorms. The frequencies of the storms’ total lightning jumps were then compared against any associated severe weather reports as an accuracy assessment. The overall performance of the algorithm among both categories was much poorer than in previous studies. While probability of detections (POD) of the 2σ algorithm were comparable to previous research, false alarm rates (FAR) were much greater than previously documented. Given these results, the 2σ algorithm does not appear fit for operational use in a weak shear environment.
Master of Science

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Haass, Moritz. "Développement de procédés de gravure à base de plasmas réactifs pulsés Pulsed plasmas for etch applications." Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00820065.

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Du fait de la réduction des dimensions en microélectronique, les procédés de gravure par plasmas ne peuvent plus satisfaire aux exigences de l'industrie. De nouvelles stratégies sont en cours de développement. Ce travail consiste en l'étude de plasmas pulsés de HBr/O2 comme une alternative pour la gravure du silicium. Divers diagnostics dans un réacteur industriel 300 mm sont utilisés pour caractériser le plasma tandis que la gravure du silicium est étudiée par XPS et par microscopie électronique. Lorsque le plasma est pulsé à faible rapport cyclique, sa température et sa dissociation sont fortement réduits. Le flux de Br radicalaire par rapport à la période ON du plasma augmente tandis que l'influence du radical O diminue, ce qui conduit à une amélioration de la sélectivité par rapport au SiO2 et à une gravure plus homogène. Les profils des structures gravées peuvent être contrôlés par la formation de la couche de passivation sur les flancs dépendant également du rapport cyclique.

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Macquisten, M. A. "The pulsed electric discharge as an acoustic probe for combustion chamber diagnostics." Thesis, London South Bank University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373899.

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Ghasemi, Esfahani Ata. "Physics and Control of Flow Over a Thin Airfoil using Nanosecond Pulse DBD Actuators." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1503204430451055.

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Goldberg, Benjamin M. "Electric Field Measurements in Non-Equilibrium ElectricDischarge Plasmas Using Picosecond Four-Wave Mixing." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1449236861.

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Limbach, Christopher M. "Characterization of nanosecond, femtosecond and dual pulse laser energy deposition in air for flow control and diagnostic applications." Thesis, Princeton University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3737448.

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The non-resonant heating of gases by laser irradiation and plasma formation has been under investigation since the development of 100 megawatt peak power, Q-switched, nanosecond pulse duration lasers and the commensurate discovery of laser air sparks. More recently, advances in mode-locking and chirped pulse amplification have led to commercially available 100 gigawatt peak power, femtosecond pulse duration lasers with a rapidly increasing number of applications including remote sensing, laser spectroscopy, aerodynamic flow control, and molecular tagging velocimetry and thermometry diagnostics. This work investigates local energy deposition and gas heating produced by focused, non-resonant, nanosecond and femtosecond laser pulses in the context of flow control and laser diagnostic applications.

Three types of pulse configurations were examined: single nanosecond pulses, single femtosecond pulses and a dual pulse approach whereby a femtosecond pre-ionizing pulse is followed by a nanosecond pulse. For each pulse configuration, optical and laser diagnostic techniques were applied in order to qualitatively and quantitatively measure the plasmadynamic and hydrodynamic processes accompanying laser energy deposition. Time resolved imaging of optical emission from the plasma and excited species was used to qualitatively examine the morphology and decay of the excited gas. Additionally, Thomson scattering and Rayleigh scattering diagnostics were applied towards measurements of electron temperature, electron density, gas temperature and gas density.

Gas heating by nanosecond and dual pulse laser plasmas was found to be considerably more intense than femtosecond plasmas, irrespective of pressure, while the dual pulse approach provided substantially more controllability than nanosecond pulses alone. In comparison, measurements of femtosecond laser heating showed a strong and nonlinearly dependence on focusing strength. With comparable pulse energy, measurements of maximum temperature rise ranged from 50K to 2000K for 500mm and 175mm focal length lenses, respectively. Experiments with various lens and pulse energy combinations indicated an important connection between gas heating and the phenomena of intensity clamping and self-guiding. The long-term behavior of the heated region varied considerably among pulse configurations. However, in each case, the formation of a toroidal vortex could be suppressed or enhanced depending on the variables of pressure, focusing and pulse energy.

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Dann, Stephen John David. "Progress towards a demonstration of multi-pulse laser Wakefield acceleration and implementation of a single-shot Wakefield diagnostic." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:6a7fe676-a9f4-4b50-a04e-9052e08cdd1b.

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An ongoing experiment is described to demonstrate the principle of multi-pulse laser wakefield acceleration, in which a plasma wakefield is resonantly excited by a train of laser pulses, spaced by the plasma wavelength. Particle-in-cell simulations of the initial single-pulse experimental setup are presented, in order to calculate the expected signal. Preliminary results are presented and future plans, based on work done so far, are discussed. Part of this work involves the implementation of a single-shot wakefield diagnostic - frequency-domain holography, which records the phase shift caused by passage of a probe pulse through the plasma. This implementation is described in detail, along with the associated analysis procedure. Practical difficulties encountered while implementing the diagnostic are discussed, along with possible ways of mitigating them in the future. A method is presented by which the noise level in the resulting phase measurements can be predicted, much more accurately than any previously published method for this technique. Methods of generating pulse trains for use in future multi-pulse laser wakefield acceleration experiments are presented. These include techniques proposed for use in this demonstration experiment, as well as one intended for use in a dedicated high-efficiency, high repetition-rate, multi-pulse driver laser. This last method, based on programmable pulse shaping using a spatial light modulator, requires a suitable mask to be computed based on the parameters of the required pulse train; an algorithm is described to perform this computation.

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Uddi, Mruthunjaya. "Non-Equilibrium Kinetic Studies Of Repetitively Pulsed Nanosecond Discharge Plasma Assisted Combustion." The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1220625444.

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VALLEAUX, THIERRY. "Diagnostic precoce et non invasif de la mort cerebrale par doppler pulse : etude prospective a propos de 56 cas." Lyon 1, 1988. http://www.theses.fr/1988LYO1M078.

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BOUHET, CUCHE ANNE. "Interet de l'echographie couplee au doppler pulse avec codage couleur dans le diagnostic des thromboses portales recentes chez l'adulte." Besançon, 1991. http://www.theses.fr/1991BESA3063.

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Goldberg, Benjamin M. "Picosecond Electric Field CARS; A Diagnostic Technique to Measure the Electric Field Development within Nanosecond Repetitively Pulsed Plasmas." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1354303147.

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Gulko, Ilya Dmitrievich. "Ns Pulse / RF Hybrid Plasmas for Plasma Chemistry and Plasma Assisted Catalysis Applications." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1598271986860656.

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Holmgren, Stefan. "Short Pulses in Engineered Nonlinear Media." Doctoral thesis, KTH, Fysik, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4234.

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Short optical pulses and engineered nonlinear media is a powerful combination. Mode locked pulses exhibit high peak powers and short pulse duration and the engineered ferro-electric KTiOPO4 facilitates several different nonlinear processes. In this work we investigate the use of structured, second-order materials for generation, characterization and frequency conversion of short optical pulses. By cascading second harmonic generation and difference frequency generation the optical Kerr effect was emulated and two different Nd-based laser cavities were mode locked by the cascaded Kerr lensing effect. In one of the cavities 2.8 ps short pulses were generated and a strong pulse shortening took place through the interplay of the cavity design and the group velocity mismatch in the nonlinear crystal. The other laser had a hybrid mode locking scheme with active electro-optic modulation and passive cascaded Kerr lensing incorporated in a single partially poled KTP crystal. The long pulses from the active modulation were shortened when the passive mode locking started and 6.9 ps short pulses were generated. High-efficiency frequency conversion is not a trivial task in periodically poled materials for short pulses due to the large group velocity mismatch. Optimization of parameters such as the focussing condition and the crystal temperature allowed us to demonstrate 64% conversion efficiency by frequency doubling the fs pulses from a Yb:KYW laser in a single pass configuration. Quasi phase matching also offers new possibilities for nonlinear interactions. We demonstrated that it is possible to simultaneously utilize several phase matched second harmonic interactions, resulting in a dual-polarization second harmonic beam. Short pulse duration of the fundamental wave is a key parameter in the novel method that we demonstrated for characterization of the nonlinearity of periodically poled crystals. The method utilizes the group velocity mismatch between the two polarizations in a type II second harmonic generation configuration. The domain walls of PPKTP exhibit second order nonlinearities that are forbidden in the bulk material. This we used in a single shot frequency resolved optical gating arrangement. The spectral resolution came from Čerenkov phase matching, a non-collinear phase matching scheme that exhibits a substantial angular dispersion. The second harmonic light was imaged upon a CCD camera and with the spectral distribution on one axis and the temporal autocorrelation on the other. From this image we retrieved the full temporal profile of the fundamental pulse, as well as the phase. The spectral dispersion provided by the Čerenkov phase matching was large enough to characterize optical pulses as long as ~200 fs in a compact setup. The Čerenkov frequency resolved optical gating method samples a thin stripe of the beam, i.e. the area close to the domain wall. This provides the means for high spatial resolution measurements of the spectral-temporal characteristics of ultrafast optical fields.
QC 20100831

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Hilbert, Vinzenz [Verfasser], Eckart Gutachter] Förster, Georg [Gutachter] [Pretzler, and Thomas [Gutachter] Wilhein. "XUV diagnostics tailored to resolve short-pulse-laserdriven ultrafast plasma dynamics / Vinzenz Johannes Hilbert ; Gutachter: Eckart Förster, Georg Pretzler, Thomas Wilhein." Jena : Friedrich-Schiller-Universität Jena, 2017. http://d-nb.info/1177600129/34.

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Huhman, Brett Michael. "A Single-Frequency Impedance Diagnostic for State of Health Determination in Li-ion 4P1S Battery Packs." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/80573.

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State-of-Health (SoH), a specified measure of stability, is a critical parameter for determining the safe operating area of a battery cell and battery packs to avoid abuse and prevent failure and accidents. A series of experiments were performed to evaluate the performance of a 4P1S battery array using electrochemical impedance spectroscopy to identify key frequencies that may describe battery state of health at any state of charge. Using a large sample number of cells, the state of health frequency, fSoH, for these LiFePO4 26650 cells is found to be 158 Hz. Four experiments were performed to evaluate the lifetime in different configurations: single-cell at 1C (2.6A), single-cell at 10C (26A), four cells in parallel at 10C (ideal match), and four cells in parallel (manufacturer match). The lifetime for each experiment set degraded substantially, with the final parallel series reaching end of life at 400 cycles, a 75.32% reduction in life compared to operating solo. Analysis of the fSoH data for these cells revealed a change in imaginary impedance at the critical frequency that corresponded to changes in the capacity and current data, supporting the development of a single-frequency diagnostic tool. An electrochemical model of the battery was generated, and it indicated the anode material was aging faster than the SEI layer, the opposite of normal cell degradation. A post-mortem analysis of cells from three configurations (baseline, single-cell, and parallel-cell) supported the modeling, as physical damage to the copper current collector in the anode was visible in the parallel-connected cell.
Ph. D.

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Welzel, Thomas. "Time-resolved characterisation of pulsed magnetron discharges for the deposition of thin films with plasma diagnostic methods." Doctoral thesis, Universitätsbibliothek Chemnitz, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-81968.

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Research on the characterisation and understanding of pulsed magnetron discharges used for the deposition of thin, especially dielectric, films has been carried out between 2003 and 2008 at Chemnitz University of Technology. This thesis is a collection and summary of the original research during this period. In the main part of the thesis, work published in peer-reviewed scientific papers is summarised and yet unpublished results are given in more detail. Different aspects highlighted in the publications are described in a general context of the characterisation of the pulsed discharges for the principal understanding. The cross-linking of the published results is addressed and where necessary extensions to the publications are given. The main part is organised in three sections. In the first one, basics of pulsed magnetron discharges, their application, and important questions are summarised. The second section describes general results and physics of the discharges that have been obtained during the research work. It also emphasises the successful development or modifications of experimental techniques for the time-resolved characterisation. The third section addresses the possibilities to modify and control the process by external parameters that are typically accessible during the application or required by it. An appendix to the thesis comprises selected published research work which is made available as reprints of the original publications. Other publications which are not included as reprints are referenced to in the main part
Untersuchungen zur Charakterisierung und zum Verständnis gepulster Magnetronentladungen, die zur Abscheidung von dünnen Schichten, besonders von dielektrischen Schichten, verwendet werden, wurden in den Jahren 2003 bis 2008 an der Technischen Universität Chemnitz durchgeführt. Diese Arbeit ist eine Sammlung und Zusammenfassung von neuen Forschungsergebnissen, die in diesem Zeitraum gewonnen wurden. Im Hauptteil der Habilitationsschrift werden die Arbeiten, die in referierten wissenschaftlichen Zeitschriften erschienen sind, zusammengefasst und noch unveröffentlichte Ergebnisse ausführlicher beschrieben. Verschiedene Aspekte, die in den Veröffentlichungen herausgestrichen wurden, werden in einem allgemeinen Zusammenhang der Charakterisierung gepulster Entladungen für ein prinzipielles Verständnis dargestellt. Querverbindungen zwischen den veröffentlichten Ergebnissen werden herausgearbeitet und wo nötig werden Erweiterungen der Originalveröffentlichungen vorgenommen. Der Hauptteil der Habilitationsschrift ist in drei Abschnitte unterteilt. Im ersten Teil werden Grundzüge gepulster Entladungen, ihre Anwendung und wesentliche Fragestellungen zusammengefasst. Der zweite Abschnitt beschreibt allgemeine Ergebnisse und die Physik der Entladungen, die während der Forschungsarbeit herausgearbeitet wurden. Er stellt auch die erfolgreiche Neuentwicklung oder Modifikation von Messtechniken zur zeitaufgelösten Charakterisierung heraus. Der dritte Abschnitt befasst sich mit den Möglichkeiten, den Beschichtungsprozess durch externe Parameter, die typischerweise während der Prozessanwendung zugänglich oder auch erforderlich sind, zu modifizieren und zu steuern. Der Anhang der Schrift beinhaltet ausgewählte Originalveröffentlichungen, die in Form von Reprints zugänglich gemacht werden. Andere Veröffentlichungen, die nicht im Anhang enthalten sind, werden im Hauptteil zitiert

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48

Welzel, Thomas. "Time-resolved characterisation of pulsed magnetron discharges for the deposition of thin films with plasma diagnostic methods." Doctoral thesis, Universitätsbibliothek Chemnitz, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-201000922.

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Research on the characterisation and understanding of pulsed magnetron discharges used for the deposition of thin, especially dielectric, films has been carried out between 2003 and 2008 at Chemnitz University of Technology. This thesis is a collection and summary of the original research during this period. In the main part of the thesis, work published in peer-reviewed scientific papers is summarised and yet unpublished results are given in more detail. Different aspects highlighted in the publications are described in a general context of the characterisation of the pulsed discharges for the principal understanding. The cross-linking of the published results is addressed and where necessary extensions to the publications are given. The main part is organised in three sections. In the first one, basics of pulsed magnetron discharges, their application, and important questions are summarised. The second section describes general results and physics of the discharges that have been obtained during the research work. It also emphasises the successful development or modifications of experimental techniques for the time-resolved characterisation. The third section addresses the possibilities to modify and control the process by external parameters that are typically accessible during the application or required by it. An appendix to the thesis comprises selected published research work which is made available as reprints of the original publications. Other publications which are not included as reprints are referenced to in the main part
Untersuchungen zur Charakterisierung und zum Verständnis gepulster Magnetronentladungen, die zur Abscheidung von dünnen Schichten, besonders von dielektrischen Schichten, verwendet werden, wurden in den Jahren 2003 bis 2008 an der Technischen Universität Chemnitz durchgeführt. Diese Arbeit ist eine Sammlung und Zusammenfassung von neuen Forschungsergebnissen, die in diesem Zeitraum gewonnen wurden. Im Hauptteil der Habilitationsschrift werden die Arbeiten, die in referierten wissenschaftlichen Zeitschriften erschienen sind, zusammengefasst und noch unveröffentlichte Ergebnisse ausführlicher beschrieben. Verschiedene Aspekte, die in den Veröffentlichungen herausgestrichen wurden, werden in einem allgemeinen Zusammenhang der Charakterisierung gepulster Entladungen für ein prinzipielles Verständnis dargestellt. Querverbindungen zwischen den veröffentlichten Ergebnissen werden herausgearbeitet und wo nötig werden Erweiterungen der Originalveröffentlichungen vorgenommen. Der Hauptteil der Habilitationsschrift ist in drei Abschnitte unterteilt. Im ersten Teil werden Grundzüge gepulster Entladungen, ihre Anwendung und wesentliche Fragestellungen zusammengefasst. Der zweite Abschnitt beschreibt allgemeine Ergebnisse und die Physik der Entladungen, die während der Forschungsarbeit herausgearbeitet wurden. Er stellt auch die erfolgreiche Neuentwicklung oder Modifikation von Messtechniken zur zeitaufgelösten Charakterisierung heraus. Der dritte Abschnitt befasst sich mit den Möglichkeiten, den Beschichtungsprozess durch externe Parameter, die typischerweise während der Prozessanwendung zugänglich oder auch erforderlich sind, zu modifizieren und zu steuern. Der Anhang der Schrift beinhaltet ausgewählte Originalveröffentlichungen, die in Form von Reprints zugänglich gemacht werden. Andere Veröffentlichungen, die nicht im Anhang enthalten sind, werden im Hauptteil zitiert

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Choi, Inchul. "OH LIF Studies of Low Temperature Plasma Assisted Oxidation and Ignition in Nanosecond Pulsed Discharge." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1299098588.

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Li, Ting. "Experimental Study of the Effects of Nanosecond-Pulsed Non-equilibrium Plasmas on Low-Pressure, Laminar, Premixed Flames." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1417632325.

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Dissertations / Theses on the topic 'Pulse diagnosis'

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