1,995 research outputs found
Implementation of CMRC on HBT power amplifier for WCDMA application
An InGaP/GaAs heterojunction bipolar transistor (HBT) is developed. By using this HBT, a power amplifier is designed for WCDMA user equipment, band-1 power class-2 application. The HBT power amplifier demonstrates a maximum output power (Pout) of 29.4dBm and a PAE of 48% at the frequency of 1.95GHz. When it operates in WCDMA standard, it achieves a Pout of 27dBm and a PAE of 32.4%. The Adjacent Channel Leakage power Ratio (ACLR) is -33dBc. To further improve the PAE, ACLR and IM3 performance, a CMRC circuit has been implemented on the HBT amplifier. The effect of CMRC on PAE and ACLR is investigated using a low power HBT amplifier. The results show that the ACLR can be improved by the CMRC. © 2004 IEEE.published_or_final_versio
Perceptions of leadership in undergraduate pharmacy students through a mixed methods study
Poster abstract from Conference; Royal Pharmaceutical Society Winter Summit 2017
Electric Springs for Reducing Power Imbalance in Three-Phase Power Systems
published_or_final_versio
Use of Smart Loads for Power Quality Improvement
Electric spring (ES) was originally proposed as a distributed demand-side management technology for making noncritical loads adaptive to the availability of intermittent renewable power generation. The second generation of ES, fed with batteries (ES-2) and associated with a noncritical load, can form a new kind of combined smart load and distributed energy storage technology for smart grids. With its four-quadrant operation, ES-2 is able to offer ancillary grid services in addition to its major functions of voltage and frequency regulation. This paper presents the operating principles and the input current control of ES-2 for power quality improvement such as power factor correction and harmonics reduction. The operating principles and the proposed input current control have been verified with the experimental results obtained from a small-scale power grid. Another weak single-phase power system fed by intermittent wind power is set up to prove the combined operation of ES-2 for power quality improvement and ES-1 (ES with capacitor storage) for voltage stabilization. The experimental results show that ES-2 with input current control can carry out power quality improvement as its ancillary function
Use of adaptive thermal storage system as smart load for voltage control and demand response
This paper describes how a large-scale ice-thermal storage can be turned into a smart load for fast voltage control and demand-side management in power systems with intermittent renewable power, while maintaining its existing function of load shaving. The possibility of modifying a conventional thermal load has been practically demonstrated in a refrigerator using power electronics technology. With the help of an electric spring, the modified thermal load can reduce power imbalance in buildings while providing active and reactive power compensation for the power grid. Based on practical data, a building energy model incorporating a large-scale ice-thermal storage system has been successfully used to demonstrate the advantageous demand-response features using computer simulation of both grid connected and isolated power systems. The results indicate the potential of using ice-thermal storage in tall buildings in reducing voltage and frequency fluctuations in weak power grids
Extending the Operating Range of Electric Spring using Back-To-Back Converter: Hardware Implementation and Control
This paper presents the first hardware implementation and control of an electric spring based on a back-to-back converter configuration. Because of its ability to provide both active and reactive power compensation, this back-to-back electric spring (ES-B2B) can substantially extend the operating range of the original version of the electric spring (ES-1) and provide enhanced voltage support and suppression functions. The hardware system and control of the ES-B2B have been successfully developed and tested. The experimental results have confirmed the effectiveness of the ES-B2B in supporting and suppressing the mains voltage. Particularly, the voltage suppression ability of the ES-B2B is superior over that of ES-1. The use of ES-B2B in a simulation study of a weak power grid has also been conducted. The ES-B2B has been found to be highly effective in mitigating voltage fluctuation caused by intermittent renewable power generation
Neurological abnormalities and neurocognitive functions in healthy elder people: A structural equation modeling analysis
Background/Aims: Neurological abnormalities have been reported in normal aging population. However, most of them were limited to extrapyramidal signs and soft signs such as motor coordination and sensory integration have received much less attention. Very little is known about the relationship between neurological soft signs and neurocognitive function in healthy elder people. The current study aimed to examine the underlying relationships between neurological soft signs and neurocognition in a group of healthy elderly
Avaliação de Metais Traço no Sedimento do Sistema Estuarino dos Rios Piraquê-açu e Piraquê-mirim (Aracruz-ES)
Aguardand
ESTUDO SOBRE CARACTERÍSTICAS GENÉTICAS DE Mycobacterium tuberculosis ISOLADO DE PACIENTES COM E SEM LESÕES CAVITÁRIAS.
Introdução: Baseado na hipótese de que a variabilidade genética de
Mycobacterium tuberculosis (MTB) pode influenciar a virulência e a gravidade da doença os perfis genéticos de isolados clínicos de MTB foram avaliados para detectar associação entre diversidade genética e gravidade da doença. Objetivos: Analisar características genéticas de isolados de MTB e verificar sua possível associação com a gravidade da TB pulmonar. Métodos: Estudo retrospectivo, caso controle, conduzido em Vitória-ES, utilizando isolados de MTB (2003 a 2006, n=214) de pacientes com TB pulmonar, cavitária (127) e não cavitária (87).
Realizou-se genotipagem por meio de RFLP-IS6110, Spoligotyping, MIRU-VNTR 24 loci, e a análise de deleções e inserções, como RDRio, RD174 utilizando PCR multiplex, bem como a detecção do Ag85C103. Realizou-se análise estatística, para verificação dos padrões de distribuição das variáveis, seguida de análises bivariadas para verificação de associações entre elas, empregando-se os teste
exato de Fisher ou Chi-quadrado, ambos com 95% de intervalo de confiança e nível de significância () < 0,05. Resultados: Após a regressão logística, as variáveis que contribuíram no modelo explicativo da doença foram baciloscopia (ORajust = 5,96; IC= 2,58-13,73) e produção de escarro (ORajust = 4,55; IC= 1,28-16,12). Não houve associação estatisticamente significativa com o restante das
variáveis.A família LAM foi a mais frequente entre os dois grupos analisados, representando 65 (62%) dos isolados no grupo cavitário e 40 isolados (38%) do grupo não cavitário. Não houve diferença estatisticamente significativa entre os grupos em relação à deleção RDRio (p=0,65) e com relação à deleção RD174 (p=0,65). Dentre os 205 isolados analisados, 25 (12%) isolados do grupo não cavitário e 43 (21%) do grupo cavitário, estavam em cluster. não houve diferença
estatisticamente significativa entre a quantidade de clusters e os grupos analisados (p= 0,4). Conclusões: Foi determinado o perfil genotípico dos isolados de pacientes com doença pulmonar, cavitária e não cavitária. Não houve associação entre a presença de cavidade e os genótipos encontrados. Não houve associação do genótipo com nenhum dos marcadores moleculares avaliados.
Palavras Chaves: Mycobacterium tuberculosis, genotipagem molecular, RFLP- IS6110, MIRU-VNTR 24 loci , Spoligotyping
Harvesting convalescent plasma for hyperimmune intravenous globulin production: a multicentre randomised double-blind controlled trial for treatment of patients with serious S-OIV H1N1 infection
Poster Presentations: Emerging / Infectious Diseases: abstract no. P107-Ab0089Symposium Theme: Translating Health Research into Policy and Practice for Health of the Populationpublished_or_final_versio
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