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Cálculo da Frequência Instantânea Cardíaca Utilizando o Algoritmo LMS e uma Interface de Aquisição de Dados / CALCULATION OF THE CARDIAC INSTANTANEOUS FREQUENCY USING ALGORITHM LMS AND AN INTERFACE OF ACQUISITION OF DATABrito, Deusdete de Sousa 11 October 2002 (has links)
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Previous issue date: 2002-10-11 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / In this work we consider the calculation of the heart instantaneous frequency
from the estimate of the weights, gotten through LMS algorithm,
(Least Mean Squares) when functioning as spectrum analyzer. It is known
that the electrocardiogram (ECG) is a signal that is characterized for a repetitive
regularity, which can be called quasi-periodicity. We explore this
characteristic to extract the instantaneous frequency of the referred signal.
For this, we use the LMS as a spectral analyzer. We use as reference inputs
pairs of sines and cosines, inside the frequency band where if it finds the
frequency of the desired signal, namely, the heart frequency. The algorithm
estimates the frequency desired in real time, with the signal acquired through
a data acquisition interface Intel 80C31. The results obtained show that the
algorithm can be recommended for this purpose, as besides being easily implemented
and generating small computational load it estimates the heart
instantaneous frequency with a relative mean error of 0.025 which represent
a difference of 18.89% between the two methods. / Neste trabalho propomos o cálculo da frequência instantânea cardíaca a
partir da estimativa do espectrograma dos pesos sinápticos, obtidos através
do algoritmo LMS, (Least Mean Square) quando funcionando como analisador
de espectro. Sabe-se que o eletrocardiograma (ECG) é um sinal que
se caracteriza por uma regularidade repetitiva, que se pode chamar quasiperiodicidade.
Exploramos aqui essa característica para extrair a frequência
instantânea do referido sinal. Para isso, utilizamos o LMS como analisador de
espectro. Utilizamos como entradas de referència pares de senos e cossenos,
dentro da faixa de frequência em que se encontra a frequência do sinal desejado,
no caso, a frequência cardíaca. O algoritmo estima a frequência
desejada em tempo real, com obtenção do sinal através de uma interface
de aquisição de dados Intel 80C31. Os resultados obtidos mostraram que o
algoritmo pode ser recomendado pra esta finalidade, pois além de ser facilmente
implementável e por gerar pequena carga computacional ele estimou
a frequência instantânea cardíaca com um erro relativo médio de 0.025 que
representa uma diferença de 18.89% entre os dois métodos.
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ESTIMAÇÂO DA FREQUÊNCIA INSTANTANEA CARDIACA UTILIZANDO O MÉTODO EAR E WAVELETS / ESTEEM OF THE FREQUENCY CARDIAC INSTANTANEOUS USING METHOD EAR AND WAVELETSSantos, Marcio de Oliveira 12 December 2003 (has links)
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Previous issue date: 2003-12-12 / The patient diagnosis can be made through a analysis of the cardiac variability
that, being formed of nervous interactions, give the status of the vagal and
sympathetic systems. The main measure to do this analysis is HRV, obtained by
RR temporal differences or spectral methods. A major disadvantage we can find
in the latter methods is a high sampling tax that yields in lost of information and
high storage cost. New methods has been developed to minimize these incovenients,
like HIF. This method have two steps: a driver function and a wavelet
filter. The proposed algorithm is based on HIF using a auto regressive method
as driver function and otimized parameters to the wavelet filter. The obtained
results are very promissor and the estimation error is smaller than traditional
methods one. / O diagnóstico de um paciente pode ser feito através da análise da variabilidade
cardíaca que, por ser resultado de interações nervosas, fornece o estado
dos sistemas vagal e simpático. A principal medida utilizada para se fazer esta
análise é a taxa de variabilidade cardíaca (HRV) que pode ser obtida por métodos
de diferença temporal de ondas R e espectrais. A principal desvantagem que é encontrada
nestes métodos é que a alta taxa de amostragem do ECG é herdada por
estes métodos, ocasionando perda de informação e o aumento de custo para armazenamento
dos dados se torna mais alto. Para que este problema fosse solucionado
foram desenvolvidas novas medidas que não apresentassem esses inconvenientes,
como o algoritmo HIF. Este algoritmo é composto de duas etapas: a construção
de uma função driver e filtragem através de uma wavelet de Gabor. O algoritmo
proposto neste trabalho foi baseado no HIF utilizando um novo método autoregressivo
(EAR) para função driver e otimizando-se os parâmetros da wavelet de
Gabor. Os resultados obtidos mostraram que o algoritmo desenvolvido é bastante
promissor e o erro de estimação é bem menor em relação a HIF.
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Centros instantâneos de rotação mandibular por meio de processamento de imagem obtida por metodologia optoeletrônica / Mandibular instantaneous centers of rotation assessed by image processing obtained by optoelectronic methodReinaldo Missaka 20 September 2010 (has links)
Nesta pesquisa, realizou-se o estudo dos movimentos de abertura e fechamento da mandíbula por meio de recursos da optoeletrônica para a obtenção e avaliação dos seus centros instantâneos de rotação. Os dados foram obtidos por duas câmeras filmadoras digitais e o processamento das imagens foi realizado por um software de computador desenvolvido junto ao Departamento de Engenharia Mecatrônica da Escola Politécnica da Universidade de São Paulo. Foram realizadas filmagens de dois pacientes, um sem sinais e sintomas de disfunção temporomandibular (DTM) e outro com deslocamento anterior unilateral do disco articular. Foi desenvolvida uma estrutura removível fixada aos dentes dos pacientes, que por meio de hastes metálicas, permitiu projetar para a porção extra-oral, o movimento da mandíbula, com pontos de referência (alvos) fixados à mesma. Foram realizadas duas filmagens do movimento de abertura e fechamento de cada paciente, uma a partir da posição de máxima intercuspidação (MIC) e outra com a mandíbula sob retrusão manual. As sequências de imagens obtidas geraram arquivos de dados em forma de coordenadas dos pontos correspondentes à variação do movimento dos alvos, bem como de suas trajetórias. Pelo processamento das imagens, foram calculados os centros instantâneos de rotação mandibular (CIRs), resultando em subsídios para análise clínica. Os resultados demonstraram que: o método desenvolvido foi capaz de capturar e processar o movimento mandibular de abertura e fechamento em um plano tridimensional de forma dinâmica, produzindo dados palpáveis para análise clínica; que foi possível, com nível de grandeza na ordem de pixels, analisar o comportamento dos CIRs da mandíbula e de toda a face dos pacientes; os CIRs se encontraram em regiões diferentes durante o movimento de abertura e fechamento com ou sem retrusão manual e com ou sem DTM; a localização dos CIRs esteve próxima à região de ATM quando se executou o movimento de abertura e fechamento com retrusão mandibular, e próximos ao forame mandibular, quando se executou o movimento de abertura e fechamento natural a partir da posição de MIC. / This study assessed the mandibular instantaneous center of rotation (ICR) of mandibular opening and closing movement using the optoelectronic method. Two digital camcorders provided the images and the data were evaluated by a software developed by the Department of Mechatronic Engineering, Polytechnic School- USP. The images were obtained from two patients, one without signs and symptoms with concerns on temporomandibular disorders and the other with unilateral disc displacement. A removable structure attached to patients teeth allowed recording references points outside of the mouth. Two movies of mandibular opening and closing movement were made of each patient, one starting from intercuspal position and the other starting from a forced retrusive mandible position. The images sequence was use to produce the location data from the references points pathway. The software processed the data and the ICR was determined to provide clinical analysis parity. Optoelectronic method can be used to analyze the mandibular three-dimensional movements and could be applied to the clinical evaluation. Also, the method allowed the assessment of the ICR and the patients faces in pixels magnitude. The ICR were detect in different regions of the mandible during the opening and closing mandibular movements of each condition. When patients started the mandibular movements from the forced retrusive position, the ICR was situated near the temporomandibular joint and, when patients started the movements from the intercuspal position, the ICR was located near the mandibular foramen.
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Calda sulfocálcica em pomares de citros: evolução da resistência em Brevipalpus phoenicis (Acari: Tenuipalpidae) e impacto sobre Iphiseiodes zuluagai (Acari: Phytoseiidae) / Lime sulfur in citrus groves: resistance evolution in Brevipalpus phoenicis (Acari: Tenuipalpidae) and impact on Iphiseiodes zuluagai (Acari: Phytoseiidae)Nadia Fernanda Bertan Casarin 06 April 2010 (has links)
A adoção da calda sulfocálcica como um produto alternativo para o controle de Brevipalpus phoenicis (Geijskes) tem sido intensificada pelos citricultores brasileiros. A calda sulfocálcica é o único produto eficiente no controle de B. phoenicis permitido pelas certificadoras de produtos orgânicos, sendo pulverizada em média 11 vezes por ano. Devido à intensificação no uso da calda sulfocálcica, os objetivos do presente trabalho foram avaliar a evolução da resistência de B. phoenicis e o impacto sobre Iphiseiodes zuluagai Denmark & Muma mediante condução de estudos de: (a) detecção e caracterização da resistência de B. phoenicis à calda sulfocálcica pelo monitoramento da suscetibilidade de populações originárias do sistema de manejo orgânico e convencional, e avaliação de resistência cruzada entre enxofre e calda sulfocálcica; (b) avaliação da toxicidade de calda sulfocálcica na evolução da resistência de B phoenicis mediante estimativa da demografia de linhagens suscetível (S), e resistentes à calda sulfocálcica (Calda-R) e enxofre (Enxofre-R); (c) avaliação da estabilidade da resistência de B. phoenicis à calda sulfocálcica em laboratório, pela estimativa da freqüência de resistência ao longo do tempo e da taxa instantânea de crescimento (ri) das linhagens S e Calda-R; e (d) avaliação do efeito letal e subletal de calda sulfocálcica sobre I. zuluagai. Para monitorar a suscetibilidade de B. phoenicis à calda sulfocálcica, concentração diagnóstica de 320 µg de enxofre/ml de água [(ppm) I.A.] foi definida pela caracterização da linhagem S com bioensaio de contato direto e residual. Diferenças significativas na suscetibilidade foram detectadas entre as populações, mas não entre os sistemas de manejo. A população com maior sobrevivência foi selecionada com concentração diagnóstica para a resistência à calda sulfocálcica (R). A CL50 estimada para as linhagens S e Calda-R à calda sulfocálcica foram 200,79 e 1.142,75 ppm respectivamente, e razão de resistência de 5,69 vezes. Foi detectada resistência cruzada positiva entre enxofre e calda sulfocálcica em B. phoenicis. A avaliação da toxicidade de calda sulfocálcica na evolução da resistência foi baseada na estimativa da ri. A ri diminuiu com o aumento das concentrações de calda sulfocálcica. As linhagens Calda-R e Enxofre-R apresentaram crescimento positivo mesmo nas concentrações de calda sulfocálcica de 3.000 e 6.000 ppm, enquanto a linhagem S foi extinta a partir de 3.000 ppm. Discriminação entre as linhagens S, e resistentes Calda-R e Enxofre-R foi verificada a partir das concentrações de 320 e 240 ppm, respectivamente. A resistência de B. phoenicis à calda sulfocálcica em laboratório foi estável. A toxicidade de calda sulfocálcica a I. zuluagai foi avaliada com bioensaio de contato direto e residual. A persistência da calda sulfocálcica a I. zuluagai foi avaliada em plantas de Canavalia ensiformis L. pulverizadas com concentração de 6.000 ppm. A calda sulfocálcica nas concentrações de 3.000 e 6.000 ppm afetou negativamente a demografia de I. zuluagai, levando a extinção. A persistência da calda sulfocálcica foi relativamente longa, resíduo com 41 dias de idade afetou significativamente a demografia de I. zuluagai. Baseado nos resultados, estratégias de manejo da resistência de B. phoenicis à calda sulfocálcica devem ser implementadas para preservar sua vida útil. / The use of the lime sulfur as an alternative product for controlling Brevipalpus phoenicis (Geijskes) has intensified in Brazilian citrus groves. The lime sulfur is the only efficient product used to control B. phoenicis and certified by organic producers with an average of 11 sprayings per year. Due to intense use of this product, the major objectives of this research were to understand the evolution of resistance of lime sulfur in B. phoenicis and the impact on Iphiseiodes zuluagai Denmark & Muma by conducting studies (a) to detect and characterize B. phoenicis resistance to lime sulfur by monitoring susceptibility in populations collected from citrus groves managed organically and conventionally, and by assessing the possible crossresistance between sulfur and lime sulfur; (b) to understand the impact of lime sulfur toxicity in B. phoenicis resistance evolution, by comparing the demography of susceptible (S), lime sulfurresistant (Lime-R) and sulfur-resistant (Sulfur-R) strains; (c) to evaluate the stability of B. phoenicis resistance to lime sulfur under laboratory conditions, by estimating temporal changes in the frequency of resistance and the instantaneous rate of increase (ri) in S and Lime-R strains; and (d) to evaluate the lethal and sublethal effect of lime sulfur on I. zuluagai. To monitor susceptibility of B. phoenicis to lime sulfur, a diagnostic concentration of 320 g of sulfur/ml of water [(ppm) AI] was defined, by characterization of S strain through direct and residual contact bioassays. Significant differences in susceptibility were detected among populations, but not between management systems. A population with the highest survivorship was identified for selecting a resistant strain to lime sulfur (R) with diagnostic concentration. The estimated LC50 of lime sulfur for S and R strains were 200.79 and 1,142.75 ppm respectively. Therefore, the resistance ratio was 5.69-fold. Cross-resistance between sulfur and lime sulfur was detected in B. phoenicis. The evaluation of the toxicity of lime sulfur on resistance evolution was based on estimation of ri. The ri decreased with the increase of lime sulfur concentrations to all strains. The Lime-R and Sulfur-R strains showed positive population growth, even at concentrations of 3,000 and 6,000 ppm, while the S strain was extinct from concentration of 3,000 ppm of lime sulfur. Discrimination between the S and the Lime-R and Sulfur-R was observed from concentrations of 320 and 240 ppm, respectively. The resistance of B. phoenicis to lime sulfur was stable under laboratory conditions. The toxicity of lime sulfur in I. zuluagai was evaluated with residual and direct contact bioassay. The persistence of lime sulfur to I. zuluagai was evaluated on plants of Canavalia ensiformis L. sprayed at concentrations up to 6,000 ppm. The lime sulfur at concentrations of 3,000 and 6,000 ppm had negative impact on population growth of I. zuluagai, by leading to extinction. The persistence of lime sulfur was relatively high because even 41-day old residues had also negative impact on I. zuluagai population growth. Based on results obtained herein, strategies for managing B. phoenicis resistance to lime sulfur should be implemented to preserve the lifetime of this product.
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An Experimental Study to Measure And Improve the Grout PenetrabilityNejad Ghafar, Ali January 2016 (has links)
An essential demand in any underground facility is to seal it against the water ingress to reduce the time and cost of the construction and the corresponding environmental hazards. To achieve this, obtaining sufficient grout spread is of great importance. Among the grouts, cement grouts with lower costs and environmental issues have been more reliable, whereas their main problem is filtration that restricts the grout spread. Several investigations have been therefore aimed to develop instruments to measure the grout penetrability as a fundamental means to improve the grout spread. Due to the difference in assumptions, limitations, and test conditions, and the deficiency in design their results are occasionally in contradiction. The question here is how to measure the grout penetrability more realistic? To answer this, two of the most frequently used instruments, Filter pump and Penetrability meter, were adjusted to approach the test conditions in Short slot. The results were discussed with respect to the origins of contradictions to better evaluate the reliability and functionality of the instruments. Among the influencing parameters on grout spread, applied pressure is a key element. The stepwise pressure increment is the method currently used to improve the grout spread in rock. Application of dynamic grouting has been studied as a solution to improve the grout spread for almost three decades. Despite some promising results, the method has not been yet industrialized due to the limited efficiency and issues in the type and frequency of the applied pressure, and the geometry of the test equipment. Therefore, finding a more efficient alternative of the applied pressure was the second goal of this study. A pneumatic pressure control system was consequently employed to examine the efficiency of the method in Short slot. The results conclusively revealed the effectiveness of the method and provided a strong basis for further development of the dynamic grouting. / Ett viktigt krav när man bygger under mark är att konstruktionen blir tillräckligt tät, så att inläckage av grundvatten minimeras. Detta minskar både projektkostnaden och eventuell miljöpåverkan. För att skapa en tät konstruktion måste injekteringsbruket spridas tillräckligt i bergmassan. Kemiska injekteringsmedel har ofta bättre spridning i bergmassan än cementbaserade bruk, men cementbaserade bruk är både billigare och ger mindre miljöpåverkan. Det finns dock en del problem med cementbaserade bruk, nämligen att cementpartiklarna filtreras och att brukets reologiska egenskaper begränsar brukets utbredning. Ett antal studier har därför utförts för att studera dessa egenskaper hos cementbaserade bruk och utveckla metoder och instrument för att mäta brukets inträngningsförmåga. Detta i syfte att förbättra brukets utbredning. Dagens metoder och instrument ger nämligen ibland motsägelsefulla resultat på grund av de olika antaganden, begränsningar och förutsättningar som används i de olika testerna. Huvudfrågan är alltså hur man kan mäta brukets inträngningsförmåga på ett mer realistiskt sätt. För att undersöka detta modifierades två vanliga mätinstrument – filterpumpen och filterpressen – för att passa förhållandena i testanordningen Short slot. Resultaten diskuterades med avseende på olika typer av skillnader mellan metoderna i syfte att utröna dels vad som påverkar inträngningsförmågan, dels instrumentens tillförlitlighet och funktionalitet. Bland de parametrar som påverkar brukets spridning i bergmassan har injekteringstrycket en central roll. I dagsläget används stegvis tryckökning för att förbättra brukets spridning i sprickigt, hårt berg. Hur man kan använda dynamisk injektering för att förbättra brukets spridning har dock undersökts under snart tre decennier. Trots lovande resultat av denna metod ännu inte börjat användas i praktiken. Ett problem är svårigheten att ta försök på labb till fältmässiga förhållanden. Ett exempel är att man använde ett tryck som varierade med hög frekvens i en spricka som modellerades med två parallella skivor utan förträngningar, vilket är mycket annorlunda jämförelse med en riktig bergspricka. I modellen blir nämligen brukets spridning starkt beroende av brukets reologiska egenskaper, medan det snarare är filtrering som är problemet i en naturlig spricka på grund av förträngningarna. Dessutom fokuserade tidigare studier endast på sprickor med en sprickvidd större än 100 μm, trots att god spridning av bruket även i de smala sprickorna med mindre än 70 μm bredd är mycket viktigt när det är höga krav på anläggningens täthet. Ett annat mål med denna licentiatuppsats var därför att hitta nya sätt att förbättra brukets spridning i berget. Därför övervakades trycket med ett pneumatiskt kontrollsystem vid tester i Short slot för att studera hur effektiv denna metod är under mer realistiska förhållanden med förträngningar på mindre än 70 μm. Resultaten visade att metoden är effektiv, vilket utgör en bra bas för att fortsätta utveckla dynamisk injektering. / <p>QC 20160413</p>
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Nonhyperemic Pressure Ratios Versus Fractional Flow Reserve: What to Do With Discordant Results?Paul, Timir K., Seto, Arnold H., White, Christopher J. 15 September 2020 (has links)
No description available.
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The influence of land use on the quality of seston in southern Appalachian stream ecosystemsWojculewski, Christy Ann 11 July 2006 (has links)
Seston is the complex of organic and inorganic particles suspended in the water column in stream ecosystems. This detrital pool is a significant vector of energy and nutrients from headwaters to the ocean. Many of the processes involved in seston generation in streams involve the terrestrial ecosystems they drain. My objective was to determine how land use influences seston quality. Seston was collected from 9 streams along a gradient of catchment forest cover, draining 3 land-use categories: forested, agricultural, and residential. Quality variations were determined through the physical composition (size classes and concentration), chemical composition (carbon, nitrogen, and phosphorous) and organic content of seston, as well as microbial respiration of associated assemblages and growth rates of Chironomus tentans fed seston. There was more seston in streams draining less forested catchments but proportionally that material was less organic. Ultrafine particles dominated seston size classes at all sites and was higher in streams with less catchment forest cover. Phosphorous content of seston, as a % of ash free dry mass, and dissolved P in the water were higher in more disturbed streams, and C:N and N:P ratios of seston were higher in forested streams. Microbial respiration and instantaneous growth rates of C. tentans were highest on residential seston, indicating seston from those streams was more bioavailable. These results indicate that the quality of seston in stream ecosystems is linked to terrestrial processes and influenced by land use. / Master of Science
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Investigation of Frequency Containment Reserves With Inertial Response and BatteriesGhasemi, Hashem, Melki, Jakob January 2019 (has links)
The rise of Renewable Energy Sources (RES) such as wind and solar power, creates new challenges for electric power systems. One of these challenges occur in Frequency Containment Reserves (FCR) on power system because of decreasing system inertia from RES. The purpose of FCR is to regulate the system frequency after a disturbance that gives rise to a Rate of Change of Frequency (RoCoF) and an Instantaneous Frequency Deviation (IFD). Conventional electricity production such as hydro and nuclear power have a contribution for the amount of inertia in the system, while RES lack this contribution of inertia.This paper studies different cases of amount of inertia to understand the impact of lower amount of inertia caused by RES on power system. A power system was simulated and the IFD and SteadyState Frequency Deviation (SSFD) of the system were examined as the nuclear powers were substituted by wind powers. The results showed that a large amount of inertia implies a small IFD and vice versa.Furthermore, this paper also studies Battery Energy Storage System (BESS) as a power support for FCR when using RES. The conclusion for the impact of the battery was to use high injected power and triggering frequency level (TLF) and vice versa to get an acceptable IFD. In other words, this means that it is possible to keep the IFD within predefined limits by using batteries and identify the appropriate range of battery control settings.
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Space Use and Annual Survival of Hybridized Mouflon Sheep in Hawaii and Comparing Estimates of Population Size through Instantaneous Sampling and Photographic Capture-RecaptureAdams, Bradley Jay 01 April 2019 (has links)
Significant efforts in conservation are devoted to the management and study of ungulates, due to their significant roles in ecosystems as well as their potential economic value. This is especially true for species considered exotic, such as mouflon sheep (Ovis musimon) in Hawaii. Effective management of an exotic species requires an understanding of ecological metrics such as space use, survival, and population size. We provided these metrics for a population of mouflon that have hybridized with feral sheep (Ovis aries) on the island of Hawaii. In Chapter 1, we quantified space use and annual survival of sheep in an area where sheep are managed for hunting opportunity. We determined that sheep have relatively small home-ranges and high rates of annual survival (>90%). In Chapter 2, we provided the first estimate of population size for the same study area while simultaneously testing the viability of a novel method of estimating population size, currently known as Instantaneous Sampling. Using photographic capture recapture as a comparison method, we compared estimates derived from both techniques and provided support for Instantaneous Sampling as an alternative method for estimating population size.
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The Effect of Environment and Social Dynamics on Lamb BehaviorPullin, Allison Nicole 27 June 2017 (has links)
No description available.
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