6 resultados para mixed-signal design
em CORA - Cork Open Research Archive - University College Cork - Ireland
Resumo:
This thesis explores the psychosocial wellbeing of sub-Saharan African migrant children in Ireland. A sociocultural ecological (Psychosocial Working Group, 2003) and resilience lens (Masten & Obradovic, 2008; Ungar, 2011) is used to analyse the experiences of African migrant children in Ireland. The research strategy employs a mixed-methods design, combining both an etic and emic perspective. Grounded theory inquiry (Strauss and Corbin, 1994) explores the experiences of African migrant children in Ireland by drawing on multi-sited observations over a period of six months in 2009, and on interviews and focus group discussions conducted with African children (aged 13-18), mothers and fathers. An emically derived ‘African Migrant Child Psychosocial Well-being’ scale was developed by drawing on data gathered through rapid ethnographic (RAE) free listing exercises carried out in Cork, Dublin and Dundalk with sixty-one participants (N=21 adults, N=28 15-18-year-olds, N=12 12-14-year-olds) and three African community key informants to elicit local understandings of psychosocial well-being. This newly developed scale was used alongside standardised measures of well-being to quantitatively measure the psychosocial adjustment of 233 African migrant children in Cork, Dublin and Dundalk aged 11-18. Findings indicate that the psychosocial wellbeing of the study population is satisfactory when benchmarked against the psychosocial health profile of Irish youth (Dooley & Fitzgerald, 2012). These findings are similar to trends reported in international literature in this field (Georgiades et al., 2006; Gonneke, Stevens, Vollebergh, 2008; Sampson et al., 2005). Study findings have implications for advancing psychosocial research methods with non-Western populations and on informing the practice of Irish professionals, mainly in the areas of teaching, psychology and community work.
Resumo:
Background: I conducted my research in the context of The National Literacy Strategy (DES, 2011), which maintains that every young person should be literate and it outlines targets for improving literacy in schools from 2011 to 2020. There has been much debate on the teaching of literacy and in particular the teaching of reading. Clark (2014) outlines how learning to read should be a developmental language process and that the approaches in the early years of schooling will colour the children’s motivation and their perception of reading as a purposeful activity. The acquisition of literacy begins in the home but this study focuses on the implementation of a literacy intervention Station Teaching in the infant classes in primary school. Station Teaching occurs when a class is divided into four or five small groups of pupils and they receive intensive tuition at four or five different Stations with the help of Support teachers: New Reading, Familiar Reading, Phonics, Writing and Oral Language. Research Questions: These research questions frame my study: How is Station Teaching implemented? What is the experience of the intervention Station Teaching from the participants’ point of view: teachers, pupils, parents? What notion of literacy is Station Teaching facilitating? Methods: I chose a pragmatic parallel mixed methods design as suggested by Mertens (2010). I collected and analysed both the quantitative and qualitative data to answer the study’s research questions. In the study the quantitative data were collected from a questionnaire issued to 21 schools in Ireland. I used Excel as a data management package and thematic analysis to analyse and present the data in themes. I collected qualitative data from a case study in a school. This data included observations of two classes over a period of a year; interviews with teachers, pupils and parents; children’s drawings, photographs, teachers’ diaries and video evidence. I analysed and presented the evidence from the qualitative data in themes. Main Findings: There are many skills and strategies that are essential to effective literacy teaching in the early years including phonological awareness, phonics, vocabulary, fluency, comprehension and writing. These skills can be taught during Station Teaching. Early intervention in the early years is essential to pupils’ acquisition of literacy. The expertise of the teacher is key to improving the literacy achievement of pupils Teachers and pupils enjoy participating in ST. Pupils are motivated to read and engage in meaningful activities during ST. Staff collaboration is vital for ST to succeed ST facilitates small group work and teachers can differentiate accordingly while including all pupils in the groups. Pupils’ learning is extended in ST but extension activities need to be addressed in the Writing Station. More training should be provided for teachers on the implementation of ST and more funding for resources should be available to schools Significant contribution of the work: The main significance of the study includes: insights into the classroom implementation of Station Teaching in infant classes and extensive research into characteristics of an effective teacher of literacy.
Resumo:
In the last decade, we have witnessed the emergence of large, warehouse-scale data centres which have enabled new internet-based software applications such as cloud computing, search engines, social media, e-government etc. Such data centres consist of large collections of servers interconnected using short-reach (reach up to a few hundred meters) optical interconnect. Today, transceivers for these applications achieve up to 100Gb/s by multiplexing 10x 10Gb/s or 4x 25Gb/s channels. In the near future however, data centre operators have expressed a need for optical links which can support 400Gb/s up to 1Tb/s. The crucial challenge is to achieve this in the same footprint (same transceiver module) and with similar power consumption as today’s technology. Straightforward scaling of the currently used space or wavelength division multiplexing may be difficult to achieve: indeed a 1Tb/s transceiver would require integration of 40 VCSELs (vertical cavity surface emitting laser diode, widely used for short‐reach optical interconnect), 40 photodiodes and the electronics operating at 25Gb/s in the same module as today’s 100Gb/s transceiver. Pushing the bit rate on such links beyond today’s commercially available 100Gb/s/fibre will require new generations of VCSELs and their driver and receiver electronics. This work looks into a number of state‐of-the-art technologies and investigates their performance restraints and recommends different set of designs, specifically targeting multilevel modulation formats. Several methods to extend the bandwidth using deep submicron (65nm and 28nm) CMOS technology are explored in this work, while also maintaining a focus upon reducing power consumption and chip area. The techniques used were pre-emphasis in rising and falling edges of the signal and bandwidth extensions by inductive peaking and different local feedback techniques. These techniques have been applied to a transmitter and receiver developed for advanced modulation formats such as PAM-4 (4 level pulse amplitude modulation). Such modulation format can increase the throughput per individual channel, which helps to overcome the challenges mentioned above to realize 400Gb/s to 1Tb/s transceivers.
Resumo:
A digital differentiator simply involves the derivation of an input signal. This work includes the presentation of first-degree and second-degree differentiators, which are designed as both infinite-impulse-response (IIR) filters and finite-impulse-response (FIR) filters. The proposed differentiators have low-pass magnitude response characteristics, thereby rejecting noise frequencies higher than the cut-off frequency. Both steady-state frequency-domain characteristics and Time-domain analyses are given for the proposed differentiators. It is shown that the proposed differentiators perform well when compared to previously proposed filters. When considering the time-domain characteristics of the differentiators, the processing of quantized signals proved especially enlightening, in terms of the filtering effects of the proposed differentiators. The coefficients of the proposed differentiators are obtained using an optimization algorithm, while the optimization objectives include magnitude and phase response. The low-pass characteristic of the proposed differentiators is achieved by minimizing the filter variance. The low-pass differentiators designed show the steep roll-off, as well as having highly accurate magnitude response in the pass-band. While having a history of over three hundred years, the design of fractional differentiator has become a ‘hot topic’ in recent decades. One challenging problem in this area is that there are many different definitions to describe the fractional model, such as the Riemann-Liouville and Caputo definitions. Through use of a feedback structure, based on the Riemann-Liouville definition. It is shown that the performance of the fractional differentiator can be improved in both the frequency-domain and time-domain. Two applications based on the proposed differentiators are described in the thesis. Specifically, the first of these involves the application of second degree differentiators in the estimation of the frequency components of a power system. The second example concerns for an image processing, edge detection application.
Resumo:
We discuss the interactions among the various phases of network research design in the context of our current work using Mixed Methods and SNA on networks and rural economic development. We claim that there are very intricate inter-dependencies among the various phases of network research design - from theory and formulation of research questions right through to modes of analysis and interpretation. Through examples drawn from our work we illustrate how choices about methods for Sampling and Data Collection are influenced by these interdependencies.
Resumo:
This novel capillary electrophoresis microchip, or also known as μTAS (micro total analysis system) was designed to separate complex aqueous based compounds, similar to commercial CE & microchip (capillary electrophoresis) systems, but more compact. This system can be potentially used for mobile/portable chemical analysis equipment. Un-doped silicon wafer & ultra-thin borofloat glass (Pyrex) wafers have been used to fabricate the device. Double-L injection feature, micro pillars column, bypass separation channel & hybrid- referenced C4D electrodes were designed to achieve a high SNR (signal to noise ratio), easy- separation, for a durable and reusable μTAS for CE use.