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Avaliação do comportamento do ângulo de fase e da dinamometria manual em pacientes submetidos à cirurgia cardíaca : estudo de coorte prospectivo / Performance evaluation of phase angle and handgrip strength in patients undergoing cardiac surgery: a prospective cohort studySilva, Taís Kereski da January 2016 (has links)
Introdução: O ângulo de fase (AF), derivado da análise de bioimpedância elétrica (BIA), tem sido interpretado como indicador de integridade da membrana celular; e a dinamometria manual têm sido usados como indicadores de prognóstico em algumas situações clínicas. Objetivos: avaliar o comportamento do AF e da dinamometria manual em pacientes submetidos à cirurgia cardíaca e associá-los com EuroSCORE e desfechos clínicos. Métodos: Estudo de coorte prospectivo com 50 pacientes submetidos à cirurgia cardíaca, com idade ≥18 anos, entre janeiro de 2015 e outubro de 2015. O AF e a dinamometria manual foram aferidos em três momentos: pré-operatório, pré-alta hospitalar e três meses após à cirurgia. Também foram coletadas as seguintes variáveis: tempo de circulação extracorpórea (CEC), isquemia, ventilação mecânica (VM), tempo de internação na Unidade de Terapia Intensiva (UTI) e tempo de internação hospitalar após à cirurgia e foi calculado o EuroSCORE. Resultados: Os pacientes foram de predominância do sexo masculino 32 (64%) com idade média de 62,8 ± 10,2 anos, tempo de estadia na UTI de 3 dias (2 – 23), tempo de internação pré-operatória de 7 (5 – 61) dias e EuroSCORE 4 (0 – 10) dias. Houve redução do AF, com diferença entre o período pré-operatório e os dois momentos de avaliação no pós-operatório (p<0,001). Quando a dinamometria manual foi avaliada ao longo do tempo foi observada uma redução entre o préoperatório e a pré-alta hospitalar (p<0,001) e recuperação dessa nos três meses após à cirurgia (p<0,001). A VM e o EuroSCORE tiveram correlação inversa com o AF e a dinamometria manual nos três momentos. A correlação do AF no período pré-operatório do EuroScore p=0,007 e o segundo e o terceiro momento p<0,001, e para os três momentos da VM (p<0,001), respectivamente. Já a correlação da dinamometria manual no primeiro e no segundo momento com o EuroSCORE e a VM p <0,001 e no terceiro momento p=0,010 e p=0,018, respectivamente. Conclusões: O AF e a dinamometria manual parecem estar associados ao tempo de VM, tempo de internação na UTI e tempo de internação no pós-operatório em pacientes submetidos à cirurgia cardíaca. / Background and aims: The phase angle (PA), derived from bioelectrical impedance analysis (BIA), have been interpreted as cell membrane integrity indicator; and the handgrip strength (HGS) have been used as prognostic indicators in some clinical situations. This study aims to evaluate the PA and HGS behavior in patients undergoing cardiac surgery and associate these with clinical outcomes and prognostic. Methods: Cohort prospective study of consecutive recruited patients undergoing cardiac surgery aged ≥18 years. The PA and HGS were measured at three set points: preoperatively, hospital predischarge and three months after surgery. Were also collected: time of cardiopulmonary bypass (CPB), ischemia, mechanical ventilation (MV), length of stay (LOS) in Intensive Care Unit (ICU) and LOS after surgery and calculated the EuroSCORE. Results: A decrease in PA was observed between the preoperative and the two postoperative stages (p<0.001). When the HGS was evaluated over time was seen a reduction between preoperative and predischarge (p<0.001) and a recovery in three months after surgery (p<0.001). The MV and EuroSCORE had an inverse association with PA and HGS in three stages. PA correlation in the first stage of the EuroSCORE p=0.007 and the second and third stage p<0.001, and for the three stages of MV (p<0.001), respectively. In HGS correlation in the first and second stage of the EuroSCORE and MV p<0,001 and in the third stage p=0.010 and p=0.018, respectively. Conclusion: PA and HGS appears to be related to MV time, LOS in ICU and LOS after surgery in patients undergoing cardiac surgery.
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Avaliação do comportamento do ângulo de fase e da dinamometria manual em pacientes submetidos à cirurgia cardíaca : estudo de coorte prospectivo / Performance evaluation of phase angle and handgrip strength in patients undergoing cardiac surgery: a prospective cohort studySilva, Taís Kereski da January 2016 (has links)
Introdução: O ângulo de fase (AF), derivado da análise de bioimpedância elétrica (BIA), tem sido interpretado como indicador de integridade da membrana celular; e a dinamometria manual têm sido usados como indicadores de prognóstico em algumas situações clínicas. Objetivos: avaliar o comportamento do AF e da dinamometria manual em pacientes submetidos à cirurgia cardíaca e associá-los com EuroSCORE e desfechos clínicos. Métodos: Estudo de coorte prospectivo com 50 pacientes submetidos à cirurgia cardíaca, com idade ≥18 anos, entre janeiro de 2015 e outubro de 2015. O AF e a dinamometria manual foram aferidos em três momentos: pré-operatório, pré-alta hospitalar e três meses após à cirurgia. Também foram coletadas as seguintes variáveis: tempo de circulação extracorpórea (CEC), isquemia, ventilação mecânica (VM), tempo de internação na Unidade de Terapia Intensiva (UTI) e tempo de internação hospitalar após à cirurgia e foi calculado o EuroSCORE. Resultados: Os pacientes foram de predominância do sexo masculino 32 (64%) com idade média de 62,8 ± 10,2 anos, tempo de estadia na UTI de 3 dias (2 – 23), tempo de internação pré-operatória de 7 (5 – 61) dias e EuroSCORE 4 (0 – 10) dias. Houve redução do AF, com diferença entre o período pré-operatório e os dois momentos de avaliação no pós-operatório (p<0,001). Quando a dinamometria manual foi avaliada ao longo do tempo foi observada uma redução entre o préoperatório e a pré-alta hospitalar (p<0,001) e recuperação dessa nos três meses após à cirurgia (p<0,001). A VM e o EuroSCORE tiveram correlação inversa com o AF e a dinamometria manual nos três momentos. A correlação do AF no período pré-operatório do EuroScore p=0,007 e o segundo e o terceiro momento p<0,001, e para os três momentos da VM (p<0,001), respectivamente. Já a correlação da dinamometria manual no primeiro e no segundo momento com o EuroSCORE e a VM p <0,001 e no terceiro momento p=0,010 e p=0,018, respectivamente. Conclusões: O AF e a dinamometria manual parecem estar associados ao tempo de VM, tempo de internação na UTI e tempo de internação no pós-operatório em pacientes submetidos à cirurgia cardíaca. / Background and aims: The phase angle (PA), derived from bioelectrical impedance analysis (BIA), have been interpreted as cell membrane integrity indicator; and the handgrip strength (HGS) have been used as prognostic indicators in some clinical situations. This study aims to evaluate the PA and HGS behavior in patients undergoing cardiac surgery and associate these with clinical outcomes and prognostic. Methods: Cohort prospective study of consecutive recruited patients undergoing cardiac surgery aged ≥18 years. The PA and HGS were measured at three set points: preoperatively, hospital predischarge and three months after surgery. Were also collected: time of cardiopulmonary bypass (CPB), ischemia, mechanical ventilation (MV), length of stay (LOS) in Intensive Care Unit (ICU) and LOS after surgery and calculated the EuroSCORE. Results: A decrease in PA was observed between the preoperative and the two postoperative stages (p<0.001). When the HGS was evaluated over time was seen a reduction between preoperative and predischarge (p<0.001) and a recovery in three months after surgery (p<0.001). The MV and EuroSCORE had an inverse association with PA and HGS in three stages. PA correlation in the first stage of the EuroSCORE p=0.007 and the second and third stage p<0.001, and for the three stages of MV (p<0.001), respectively. In HGS correlation in the first and second stage of the EuroSCORE and MV p<0,001 and in the third stage p=0.010 and p=0.018, respectively. Conclusion: PA and HGS appears to be related to MV time, LOS in ICU and LOS after surgery in patients undergoing cardiac surgery.
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Avaliação do comportamento do ângulo de fase e da dinamometria manual em pacientes submetidos à cirurgia cardíaca : estudo de coorte prospectivo / Performance evaluation of phase angle and handgrip strength in patients undergoing cardiac surgery: a prospective cohort studySilva, Taís Kereski da January 2016 (has links)
Introdução: O ângulo de fase (AF), derivado da análise de bioimpedância elétrica (BIA), tem sido interpretado como indicador de integridade da membrana celular; e a dinamometria manual têm sido usados como indicadores de prognóstico em algumas situações clínicas. Objetivos: avaliar o comportamento do AF e da dinamometria manual em pacientes submetidos à cirurgia cardíaca e associá-los com EuroSCORE e desfechos clínicos. Métodos: Estudo de coorte prospectivo com 50 pacientes submetidos à cirurgia cardíaca, com idade ≥18 anos, entre janeiro de 2015 e outubro de 2015. O AF e a dinamometria manual foram aferidos em três momentos: pré-operatório, pré-alta hospitalar e três meses após à cirurgia. Também foram coletadas as seguintes variáveis: tempo de circulação extracorpórea (CEC), isquemia, ventilação mecânica (VM), tempo de internação na Unidade de Terapia Intensiva (UTI) e tempo de internação hospitalar após à cirurgia e foi calculado o EuroSCORE. Resultados: Os pacientes foram de predominância do sexo masculino 32 (64%) com idade média de 62,8 ± 10,2 anos, tempo de estadia na UTI de 3 dias (2 – 23), tempo de internação pré-operatória de 7 (5 – 61) dias e EuroSCORE 4 (0 – 10) dias. Houve redução do AF, com diferença entre o período pré-operatório e os dois momentos de avaliação no pós-operatório (p<0,001). Quando a dinamometria manual foi avaliada ao longo do tempo foi observada uma redução entre o préoperatório e a pré-alta hospitalar (p<0,001) e recuperação dessa nos três meses após à cirurgia (p<0,001). A VM e o EuroSCORE tiveram correlação inversa com o AF e a dinamometria manual nos três momentos. A correlação do AF no período pré-operatório do EuroScore p=0,007 e o segundo e o terceiro momento p<0,001, e para os três momentos da VM (p<0,001), respectivamente. Já a correlação da dinamometria manual no primeiro e no segundo momento com o EuroSCORE e a VM p <0,001 e no terceiro momento p=0,010 e p=0,018, respectivamente. Conclusões: O AF e a dinamometria manual parecem estar associados ao tempo de VM, tempo de internação na UTI e tempo de internação no pós-operatório em pacientes submetidos à cirurgia cardíaca. / Background and aims: The phase angle (PA), derived from bioelectrical impedance analysis (BIA), have been interpreted as cell membrane integrity indicator; and the handgrip strength (HGS) have been used as prognostic indicators in some clinical situations. This study aims to evaluate the PA and HGS behavior in patients undergoing cardiac surgery and associate these with clinical outcomes and prognostic. Methods: Cohort prospective study of consecutive recruited patients undergoing cardiac surgery aged ≥18 years. The PA and HGS were measured at three set points: preoperatively, hospital predischarge and three months after surgery. Were also collected: time of cardiopulmonary bypass (CPB), ischemia, mechanical ventilation (MV), length of stay (LOS) in Intensive Care Unit (ICU) and LOS after surgery and calculated the EuroSCORE. Results: A decrease in PA was observed between the preoperative and the two postoperative stages (p<0.001). When the HGS was evaluated over time was seen a reduction between preoperative and predischarge (p<0.001) and a recovery in three months after surgery (p<0.001). The MV and EuroSCORE had an inverse association with PA and HGS in three stages. PA correlation in the first stage of the EuroSCORE p=0.007 and the second and third stage p<0.001, and for the three stages of MV (p<0.001), respectively. In HGS correlation in the first and second stage of the EuroSCORE and MV p<0,001 and in the third stage p=0.010 and p=0.018, respectively. Conclusion: PA and HGS appears to be related to MV time, LOS in ICU and LOS after surgery in patients undergoing cardiac surgery.
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Compósitos com biochar e carvão vegetal para camadas de pavimentos asfálticos / Composites with biochar and vegetable charcoal for asphalt pavement layersTorres, Alemar Pereira, 92981056447 18 June 2018 (has links)
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Previous issue date: 2018-06-18 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Biochar is a charcoal derived from the carbonization of biomass under a low oxygen atmosphere. Its origin is due to the study developed in the so-called "Indian black earth", which considerably improves the agricultural properties of a soil. In the work under study the influence of biochar as a participant of composites with soil and asphalt mixtures is analyzed by means of the four point bending test. We also compare these results regarding the responses of the formulations with the presence of native charcoal from the Amazon region. For this, prismatic formations of natural clay soil (SN), soil-charcoal (SCV), soil-biochar (SBC), asphalt concrete (CA), asphalt-charcoal concrete (CACV) and concrete asphalt-biochar (CABC). The results showed that the biomass, which participates in composites with the clay soil, improved the stiffness properties, with the purpose of its use in base and sub-base of pavements, culminating in higher values for complex module regarding the mixtures with charcoal . Allus asphaltic composites with biochar and charcoal were verified for both values of stiffness inferior to the standard asphalt concrete, considering average temperature of 25oC. However, for the 40oC temperature, representative of the surface of the pavements of the city of Manaus, these formulations proved to be more advantageous in comparison to the concrete reference, conceiving an alternative for the achievement of road systems with better performance in the Amazon region. / O biochar é um carvão vegetal oriundo da carbonização de biomassa sob baixa atmosfera de oxigênio. Sua origem deve-se ao estudo desenvolvido na chamada “terra preta de índio”, a qual melhora consideravelmente as propriedades agrícolas de um solo. No trabalho em pauta analisa-se a influência do biochar como partícipe de compósitos com solo e misturas asfálticas, por meio do ensaio de flexão a quatro pontos. Também se comparam tais resultados relativos as respostas das formulações com a presença do carvão vegetal nativo da região amazônica. Para tal moldaram-se os corpos de prova de formato prismático do solo argiloso natural (SN), solo-carvão vegetal (SCV), solo-biochar (SBC), concreto asfáltico (CA), concreto asfáltico-carvão vegetal (CACV) e concreto asfáltico-biochar (CABC). Os resultados registraram que o biocarvão, participante em compósitos com o solo argiloso, melhorou as propriedades de rigidez, com a finalidade de seu emprego em base e sub-base de pavimentos, culminando em maiores valores para módulo complexo respeitante as misturas com o carvão vegetal. Alusivo aos compósitos asfálticos com biochar e carvão vegetal, verificou-se para ambos valores de rigidez inferior ao concreto asfáltico padrão, considerando temperatura média de 25oC. No entanto, para a temperatura de 40oC, representativa da superfície dos pavimentos da cidade de Manaus, tais formulações se mostraram mais vantajosos frente ao concreto referência, concebendo uma alternativa para a consecução de sistemas viários com melhor desempenho na região Amazônica.
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Efeitos da ventilação mecânica não invasiva na mobilidade e assincronia tóraco-abdominal em pacientes com DPOC / Effects of non-invasive ventilation in thoraco-abdominal mobility in patients with COPDDias, Fernanda Dultra 18 December 2016 (has links)
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Previous issue date: 2016-12-18 / Introduction: The VMNI has been showing an adjuvant treatment resource for patients with stable COPD or exacerbation. However little is known about the action that the NIV promotes in thoracic and abdominal and mobility if it is able to promote improvement of asynchrony. Objectives: to evaluate the effects of the NIV in thoracic and abdominal mobility, comparing variables in spontaneous breathing and during the use of NIV in patients with COPD by OEP. Methods: Two groups of individuals (GC with 14 healthy and COPD with 16 patients) were assessed in relation to the thoracic-abdominal asynchrony, respiratory and àcontrubuição variables of each thoracic compartment using a Plethysmograph SPOS System (BTS, Italy) in spontaneous breathing and with two VMNI modes. Results: Patients with COPD evaluated presented ATA in home, we also observed that the COPD asynchrony in all compartments in relation to healthy, which in turn has always maintained its AF next to zero and when it observes only the COPD group, using both methods of VMNI promote decrease of asynchrony in compartment CTS vs. ABD and the key changes found in the COPD group are related to the distribution of aid and action of each compartment toracico. Conclusion: There are ATA in patients with COPD, even at home, the degree of airway obstruction of these patients correlates with the presence of asynchronous Thoracoabdominal, the use of VMNI in the mode continuous positive airway pressure is able to improve thoracic abdominal synchrony in patients with COPD, as well as the use of some blood pressure to A6 led and that the VMNI is able to promote changes in compartmental contribution without promoting significant changes in respiratory variables in patients with COPD compared with age-matched healthy. / Introdução: A VMNI vem se mostrando um recurso adjuvante ao tratamento de pacientes com DPOC estável ou na exacerbação.No entanto pouco se sabe sobre a ação que a VNI promove na mobilidade tóraco abdominal e se é capaz de promover melhora da assincronia respiratória. Objetivos: Avaliar os efeitos da VNI na mobilidade e sincronia tóraco-abdominal, comparando as variáveis em respiração espontânea e durante o uso de VNI em pacientes com DPOC por meio da OEP. Método: Dois grupos de indivíduos (GC com 14 saudáveis e DPOC com 16 pacientes) foram avaliados em relação à assincronia toraco-abdominal, às variáveis respiratórias e àcontrubuição de cada compartimento torácico, utilizando-se um pletismógrafo OEP System (BTS, Italy) em respiração espontânea e com aplicação de dois modos de VMNI. Resultados: Os pacientes com DPOC avaliados apresentaram ATA em repouso, observou-se também que o DPOC apresentou assincronia em todos os compartimentos em relação ao Saudável, que por sua vez sempre manteve seu AF próximo a zero e quando se observa somente o grupo DPOC, o uso de ambas as modalidades de VMNI promovem diminuição da assincronia no compartimento CTS vs ABD e as principais alterações encontradas no grupo DPOC estão relacionadas a distribuição da contribuição e ação de cada compartimento toracico. Conclusão: Há ATA em pacientes com DPOC, mesmo em situação de repouso, o grau de obstrução das vias aéreas desses pacientes não se correlaciona com a presença de assincronia toracoabdominal, o uso de VMNI no modo pressão positiva contínua nas vias aéreas é capaz de melhorar a sincronia tóraco-abdominal em pacientes com DPOC, assim como a utilização de alguns níveis pressóricos de Bilevel e que a VMNI é capaz de promover alterações na contribuição compartimental sem promover alterações significativas nas variáveis respiratórias nos pacientes com DPOC comparando com saudáveis pareados por idade.
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Investigation on Interleaved Boost Converters and ApplicationsWang, Chuanyun 25 August 2009 (has links)
With the rapid evolving IT technologies, today, the power factor correction (PFC) design is facing many challenges, such as power scalability, high entire-load-range efficiency, and high power density. Power scalability is a very desirable and cost-effective approach in the PFC design in order to keep up with servers' growing power requirements. Higher power density can eventually reduce the converter cost and allows for accommodating more equipment in the existing infrastructures. Driven strongly by economic and environmental concerns, high entire-load-range efficiency is more and more required by various organizations and programs, such as the U.S. Energy Star, Climate Savers, and German Blue Angel. Today, the existing boost PFC is reaching its limitations to meet these challenges simultaneously. Using the cutting-edge semiconductor devices, further efficiency improvement at light load is still needed. There are limited approaches available for increasing the power density due to the large EMI filter and inductor size.
Interleaved multi-channel boost PFC is a promising candidate to meet those challenges, but the interleaved boost converter is a less explored area. On the other hand, the multi-channel interleaved buck converter for the VR application has been intensively studied and thoroughly explored. One basic approach of this study is trying to extend the existing knowledge and techniques obtained from multiphase buck converters to the multi-channel interleaved boost converters since there are similarities existed between the multi-phase buck and the multi-channel boost converters.
The existing studies about the interleaving impact on the EMI filter design are based on the time domain ripple cancellation effect. This approach is good enough for most of the filter designs. However, unlike the conventional filter designs, the EMI filter design is a specification related process. Both the EMI standard and the EMI measurement are based on the frequency domain spectrum. Limited by the existing analysis approaches, it is difficult to provide a clear picture about how exactly the multi-channel interleaving will impact the EMI filter design. The interleaving impact on the Common Mode (CM) noise also has not been studied in any existing literatures for the same reason. In this study, the frequency domain analysis method was adopted. With the double Fourier integral transformation, a closed-form expression of all the harmonics of the noise sources can be obtained. With all the detailed phase relationship of the switching frequency harmonics and all the side band harmonics, the multi-channel interleaving impact on both the differential mode (DM) and CM filter design can be clearly understood and summarized. According to the design curves provided, the EMI filter size can be effectively reduced by properly choosing the interleaving channel number and the switching frequency. The multi-channel interleaving impact on the output capacitor current ripple is also studied and summarized in this dissertation.
It should be pointed out that interleaving only reduces the total input and output current ripples; the inductor current in each channel still has large ripple if small inductance is used. Similar to the multi-phase buck converter, coupling inductors result in different equivalent inductances for input current ripple and inductor current ripple for boost converters. Keeping the inductor current ripple magnitude the same, inverse coupling inductors between the interleaved channels can reduce the inductor size. However, the DM filter size is increased due to larger input current. Based on the investigation on the total magnetic component weight, inverse coupling inductor can reduce the total magnetic component weight. The reduction is more pronounced for lower switching frequency design when the inductor size is dominating among the total magnetic components.
Based on the harmonic cancellation, and with all the detailed phase relationship of the switching frequency harmonics and all the side band harmonics, a novel phase angle control method is proposed to maximize the reduction of the EMI filter. For example, in a 2-channel interleaved PFC, just by changing the interleaving scheme to 90 degree phase shift, 39% total volume reduction of the EMI filter can be achieved. The proposed phase angle controlled multi-channel PFC is experimentally demonstrated and verified on a digital controlled 4-channel PFC. The phase angle control method proposed in the multi-channel boost converter can be applied back to the multi-phase buck converter as well. The harmonic cancellation principle will be the same as the multi-channel boost converter. The same benefits can be obtained when the requirement is defined in the frequency domain, e.g. the EMI Standard.
The interleaved multi-channel configuration makes it possible to implement the phase-shedding to improve the PFC light load efficiency. By decreasing the number of active channels according to the load, the PFC light load efficiency can be optimized. However, shedding phases can reduce the ripple cancellation effect as well, which will result in the EMI noise increase and losing the benefit on the EMI filter. By applying the proposed phase-shedding with phase angle control strategy, the phase shedding impact on the EMI filter design can be minimized. The light load efficiency can be improved without compromising the EMI filter size. Then, adaptive frequency controlled PFC is proposed to further improve the PFC light load efficiency. The proposed light load efficiency improvement strategies are combined and implemented on the platform of the digital controlled 4-channel PFC. The benefit of improving the light load efficiency is experimentally verified. The EMI performance is also evaluated with the EMI measurement results obtained from the PFC prototype.
Following the same approach explored, the benefits of interleaved boost converter can be further extended other applications, such as the boost converter in the Hybrid Electric Vehicles (HEV) and photovoltaic (PV) system. / Ph. D.
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Frequency Monitoring Network (FNET) Algorithm Improvements and Application DevelopmentXia, Tao 22 January 2010 (has links)
The Internet Based real-time GPS synchronized wide-area Frequency Monitoring Network (FNET) is an extremely low cost and quickly deployable wide-area frequency measurement system with high dynamic accuracy which consists of Frequency Disturbance Recorder (FDR) distributed to more than 100 places around North America and an Information Management System situated at Virginia Tech. Since its first FDR deployment in 2003, the FNET system has been proved to be able to reliably receive phasor data accurately measured at and instantaneously sent via the Internet from different locations of interest, and efficiently run the analyzing program to detect and record significant system disturbances and subsequently estimate the location of disturbance center, namely the event location, in the electric grid based on the information gathered. The excellent performance of the FNET system so far has made power grid situation awareness and monitoring based on distribution level frequency measurements a reality, and thus advances our understanding of power system dynamics to a higher level and in a broader dimensionality.
Chapter 1 and Chapter 2 of this dissertation briefly introduce the genesis and the architecture of the FNET system, followed by a summary of its concrete implementations. Chapter 3 and Chapter 4 outline FNET frequency estimation algorithm and phase angle estimation algorithm, including their attributes and the new methodologies to enhance them. In Chapter 5, the report discusses the algorithms developed at FNET to detect the frequency disturbance and estimate the disturbance location by the triangulation procedure using real-time frequency data and geographic topology of the FNET units in the power grid where the disturbance occurs. Then, the dissertation proceeds to introduce the FNET angle-based power system oscillation detection and present some research about Matrix Pencil Modal Analysis of FNET phase angle oscillation data in the following two chapters. Lastly, the content of this report is summarized and the future work envisioned in Chapter 8. / Ph. D.
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Análise de parâmetros de impedância bioelétrica, bioquímicos, morfológicos e funcionais em idosos sarcopênicos e não sarcopênicos submetidos a treinamento resistido convencional e com resistência elástica : ensaio clínico aleatório /Osco, Karla Minacca January 2019 (has links)
Orientador: Luís Alberto Gobbo / Resumo: A população idosa com idade igual ou superior a 60 anos dobrou na última metade do século XX. O envelhecimento é um processo inevitável com consequências deletérias e progressivas para o corpo humano, comprometendo os seus diferentes sistemas, tais como o fisiológico, o morfológico, o funcional e o endócrino. A perda progressiva de massa e força muscular, associada à função é denominada sarcopenia, e como consequência, promove maior risco para incapacidade funcional, fragilidade, quedas, fraturas, hospitalizações, institucionalizações, óbito precoce e alterações imunológicas. Em idosos as alterações no sistema imunológico podem ocorrer devido ao aumento da concentração sanguínea de citocinas pró-inflamatórias que agrava o estado sarcopênico, acarretando um processo de inflamação crônica de baixo grau (LGI, low grade inflammation). Dentre os parâmetros observados na avaliação da sarcopenia, a análise de impedância bioelétrica (BIA) vem sendo utilizada há tempo para mensuração dos diferentes componentes corporais dentro do sistema morfológico, especialmente os tecidos adiposo e muscular. Mais recentemente, parâmetros brutos da BIA (R, resistência e Xc, reatância) têm sido utilizados para a avaliação da saúde celular (PhA, ângulo de fase e a análise de vetores de impedância bioelétrica (BIVA, bioimpedance vector analysis). Com a finalidade de reverter ou atenuar os efeitos deletérios do envelhecimento, programas de treinamento físico, mais especificamente o treinamento resistido... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
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Mean and Fluctuating Pressures on an Automotive External Rear View Mirror.Jaitlee, Rajneesh, jaitlee@gmail.com January 2006 (has links)
The primary function of an automobile rear View Mirror is to provide the driver with a clear vision interpretation of all objects to the rear and side of the vehicle. The rear View Mirror is a bluff body and there are several problems associated with the rear View Mirror. These include buffeting, image distortion (due to aerodynamically induced and structural vibration), aerodynamically induced noise (due to cavities and gaps) and water and dirt accumulation on Mirror glass Surface. Due to excessive glass vibration, the rear View Mirror may not provide a clear image. Thus, vibrations of Mirror can severely impair the driver's vision and safety of the vehicle and its occupants. The rear View Mirrors are generally located close to the A-pillar region on the side window. A conical vortex forms on the side window close to A-pillar due to A-pillar geometry and the presence of side rear View Mirror and flow separation from it makes the airflow even more complex. The primary objective of this work is to study the aerodynamic pressures on Mirror Surface at Various speeds to determine the effects of aerodynamics on to Mirror vibration. Additionally, the Mirror was modified by Shrouding around the external periphery to determine the possibility of minimisation of aerodynamic pressure fluctuations and thereby vibration. The Shrouding length used for the analysis was of 24mm, 34mm and 44mm length. The mean and fluctuating pressures were measured using a production rear side View Mirror fitted to a ¼ quarter production passenger car in RMIT Industrial Wind Tunnel. The tests were also conducted in semi-isolation condition to understand influence of the A-pillar geometry. The mean and fluctuating pressures were converted into non-dimensional pressure coefficients (Cp and Cprms) and the frequency content of the fluctuating pressure was analysed. The results show that the fluctuating aerodynamic pressures are not uniformly distributed over an automobile Mirror Surface. The highest magnitude of fluctuating pressure for the standard Mirror was found at the central bottom part of the Mirror Surface. The highest magnitude of fluctuating pressure for the modified Mirror was found at the central top part of the Mirror Surface. As expected, the modification has significant effect on the magnitude of fluctuating pressure. The results show that an increase of Shrouding length reduces the magnitude of the fluctuating pressure. The frequency-based analysis was done to understand the energy characteristics of the flow, particularly to its phase, since it is the out of phase components that usually cause Mirror rotational vibration. The spectral analysis showed that the magnitude of the energy distribution reduces with increase of shrouding length throughout the frequency range. Flow visualisation was also used to supplement the pressure data. The effects of yaw angles were not included in this study, however, are thought to be worthy of further investigation. On road testing and the variation of mirror locations might have some effects on the fluctuating pressures. These need to be investigated in the future work. The quarter model used in this study was a car specific. However, for more generic results, a simplified model with variable geometry can be used in future study.
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Avaliação do uso do ângulo de fase e da força do aperto de mão como fatores prognósticos para pacientes cirúrgicos oncológicos / Evaluation of the phase angle and handgrip strength as prognostic factors for surgical patients with cancerHärter, Jéssica 19 August 2016 (has links)
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Previous issue date: 2016-08-19 / Sem bolsa / A desnutrição é frequente no paciente oncológico e pode ter grande impacto no prognóstico. Assim, o uso de medidas capazes de detectar precocemente alterações no estado nutricional e funcional se torna importante. Portanto, o presente estudo buscou avaliar o ângulo de fase, a força do aperto de mão e a sarcopenia como fatores prognósticos de morbimortalidade pós-operatória em uma amostra de pacientes oncológicos. A coleta de dados ocorreu no Hospital Escola da Universidade Federal de Pelotas/EBSERH entre os meses de novembro de 2015 a maio de 2016. O ângulo de fase foi obtido através de teste de bioimpedância elétrica e para as análises foi padronizado, ou seja, ajustado para sexo e idade. A força do aperto de mão foi obtida por dinamômetro hidráulico. O diagnóstico de sarcopenia seguiu os critérios estabelecidos pelo European Working Group on Sarcopenia in Older People. O estado nutricional foi avaliado através da Avaliação Subjetiva Global Produzida Pelo Paciente. Foram considerados desfechos as complicações pós-operatórias e a internação prolongada. A classificação das complicações foi feita através da Classificação de complicações cirúrgicas de Clavien-Dindo e o tempo de internação foi separado em tercis para definir o que seria considerado tempo de internação prologando, que ficou definido como internação por um período maior ou igual a oito dias. A amostra final do estudo foi composta por 60 pacientes. A prevalência de desnutrição foi de 28,3% e a de sarcopenia foi de 16,9%. O ângulo de fase foi significativamente menor entre os pacientes que apresentaram complicações pós-operatórias graves e internação prolongada. A desnutrição esteve significativamente associada a esses dois desfechos, enquanto a força do aperto de mão e a sarcopenia não mostraram associação. Nesse volume consta o projeto de pesquisa, o relatório do trabalho de campo e o artigo gerado a partir dos resultados encontrados. / Malnutrition is frequent in cancer patients and can have a big impact on prognosis. The use of measures capable of detecting early changes in nutritional and functional states becomes important. The present study aims to evaluate phase angle, sarcopenia and handgrip strength as prognostic factors of postoperative morbimortality in patients with cancer. The data were collected in Hospital Escola da Universidade Federal de Pelotas/EBSERH between November 2015 and May 2016. Phase angle was measured through a bioelectric impendence test and was standardized for analysis based on gender and age. Handgrip strength was measured through hydraulic dynamometer. The sarcopenia diagnosis followed the criteria of the European Working Group on Sarcopenia in Older People. The nutritional status of each subject was evaluated through Patient Generated Subjective Global Assessment. The prognostic outcomes we considered were postoperative complications and long hospital stay. The classification of postoperative complications was given by the Clavien-Dindo Classification and the length of stay was split in tertiles to define what we would consider a long length stay, which was defined as the length of stay longer than or of that of eight days. The final sample had 60 subjects. The malnutrition prevalence was 28.3% and the sarcopenia prevalence was 16.9%. The phase angle was significantly lower among the subjects who showed severe postoperative complication or long hospital stay The malnutrition was significantly associated to this outcomes while the handgrip strength and sarcopenia did not show any association. In the present work we present the research project, the field report and the article based on the research results.
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