944 resultados para pulse-shaping


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This paper proposes a ramp dual-pulse actuation-voltage waveform that reduces actuation-voltage shift in capacitive microelectromechanical system (MEMS) switches. The proposed waveform as well as two reported waveforms (dual pulse, and novel dual-pulse) are analyzed using equivalent-circuit and equation models. Based on the analysis outcome, the paper provides a clear understanding of trapped charge density in the dielectric. The results show that the proposed actuation-voltage waveform successfully reduces trapped charge and increases lifetime due to lowering of actuation-voltage shift. Using the proposed actuation-voltage waveform, the membrane reaches a steady state on the electrode faster.

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Studying the Effectiveness of Teacher Education (SETE) is a four-year, mixed-method, longitudinal study investigating graduate teachers’ perceptions on the effectiveness of teacher education. The main target population were new teacher education graduates (those who graduated in 2010/2011) registered as teachers in Victoria and Queensland. The secondary target population were the school principals in those schools where the graduate teacher was employed. Identification of the main target population is drawn from Teacher Registration Authority databases. The quantitative component of the SETE project involves tracking teacher education graduates through a series of four surveys, collecting data on the influence of initial teacher education on graduate teachers’ perceptions of their preparation and effectiveness across key areas and in diverse school settings.

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This research paper examines the evolution of corporate reporting and governance in Iran over the last century. The approach adopted was to provide an historical perspective to examine the environment within which Iranian corporate reporting has emerged and been shaped. An historical framework allows the study to focus on the evolution and development of corporate reporting practice in Iran. By adopting an historical framework, this study is able to inform future research based on models that adopt an evolutionary approach to the assessment of environmental factors on economic systems. The conclusion reached in this study is that socio-economic and political changes during the century have been opportune as drivers of corporate reporting in Iran. The study makes an incremental contribution to the existing accounting history literature for Asia / Middle East / developing countries.

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Childhood cardiovascular risk factors affect vascular function long before overt cardiovascular disease. Twin studies provide a unique opportunity to examine the influence of shared genetic and environmental influences on childhood cardiovascular function. We examined the relationship between birth parameters, markers of adiposity, insulin resistance, lipid profile and blood pressure and carotid-femoral pulse wave velocity (PWV), a validated non-invasive measure of arterial stiffness in a healthy cohort of school-aged twin children. PWV was performed on a population-based birth cohort of 147 twin pairs aged 7-11 years. Fasting blood samples, blood pressure and adiposity measures were collected concurrently. Mixed linear regression models were used to account for twin clustering, within- and between-twin pair associations. There were positive associations between both markers of higher adiposity, insulin resistance, elevated triglycerides and PWV, which remained significant after accounting for twin birth-set clustering. There was a positive association between both diastolic and mean arterial blood pressure and PWV in within-pair analysis in dizygotic, but not monozygotic twins, indicating genetic differences evident in dizygotic not monozygotic twins may affect these associations. Increased blood pressure, triglycerides and other metabolic markers are associated with increased PWV in school-aged twins. These results support both the genetic and environmental contribution to higher PWV, as a marker of arterial stiffness, and reiterate the importance of preventing metabolic syndrome from childhood.

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This paper unpacks the meanings and implications of the mobility of international students in vocational education – an under-researched group in the field of international education. This four-year study found that transnational mobility is regarded as a resourceful vehicle to help international students ‘become’ the kind of person they want to be. The paper justifies the value of re-conceptualising student mobility as a process of ‘becoming’. Mobility as ‘becoming’ encompasses students’ aspirations for educational, social, personal and professional development. Theorising mobility as ‘becoming’ captures international students’ lived realities and has the potential to facilitate the re-imagining of international student mobility with new outlooks. By theorising mobility as ‘becoming’, this research suggests the importance of drawing on the integrated and transformative nature of Bourdieu’s forms of capital in understanding the logics and practice of the social field – international student mobility.

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Background: In Australia, venues which provide gambling activities also provide activities that are utilised by families and children. However, there has been limited theoretical or empirical discussion about whether engagement with non-gambling activities may play a role in shaping pathways to current or future engagement in gambling within these environments. We examined marketing tactics for non-gambling and gambling activities in Clubs. Using this data, we propose a conceptual model to test the role of non-gambling activities within gambling environments in shaping gambling attitudes and consumption intentions.

Methods
: This study used a mixed method interpretive content analysis to review the marketing activities on the websites of a sample of 65 registered Clubs in New South Wales, Australia. We identified the extent and nature of techniques used to market gambling and non-gambling activities, particularly non-gambling activities directed towards families and children.

Results
: Clubs use various marketing tactics to appeal to families and encourage parents to bring their children into venues. We hypothesise that marketing aimed at bringing children and families into gambling environments may play a role in shaping children’s and adults perceptions of these environments and may be influential in the development of a pathway that increases the likelihood that children will continue to visit these environments as adults, and subsequently the extent to which they engage in gambling later in life.

Conclusions:
Future research should explore how the presence of family-friendly activities in Clubs and other venues with gambling activities may play a role in shaping future gambling attitudes and behaviours.

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O objetivo deste trabalho foi avaliar as taxas de ativação e de clivagem de oócitos bovinos tratados com estrôncio (10mm de SrCl2), após maturação in vitro por 27-28 horas. No experimento 1, os tratamentos foram: S4 - ativação pelo estrôncio por 4 horas; S12 - ativação pelo estrôncio por 12 horas; S30 - ativação pelo estrôncio por 30 horas; e P - ativação por pulso elétrico (3 pulsos de 1,0kv/cm). No experimento 2 os tratamentos foram: PS4 - ativação combinada pelo pulso elétrico e pelo estrôncio por 4 horas; S4P - ativação pelo estrôncio por 4 horas e pelo pulso elétrico; e PS30 - ativação pelo pulso elétrico e pelo estrôncio por 30 horas. No experimento 1, todos os tratamentos apresentaram taxas similares de ativação (83-90%; P>0,05). Para clivagem, P foi melhor (53%; P<0,05) do que todos os tratamentos com estrôncio (6 a 28%). No experimento 2, o tratamento S4P apresentou melhor taxa de ativação (88%; P<0,05) do que PS4 e PS30 (60 e 68%, respectivamente). Para clivagem, observou-se o mesmo padrão, S4P (65%; P<0,05) e PS4 e PS30 (37% e 44%, respectivamente). Conclui-se que o estrôncio é capaz de ativar oócitos bovinos e sua combinação com pulso elétrico não melhora a ativação. Este é o primeiro relato demonstrando que o estrôncio ativa oócitos bovinos.