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Dissertations / Theses on the topic 'Phonics'
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Giesige, Lisa Jane. "Can you see Phonics? Phonics for Students who are Deaf or Hard of Hearing." Bowling Green State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1206105536.
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Tang, Shuk-yee, and 鄧淑儀. "The phonics approach and reading English." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B26813932.
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Wong, Wing-sze Winsy. "Phonics knowledge of Hong Kong college students." Click to view the E-thesis via HKU Scholars Hub, 2003. http://lookup.lib.hku.hk/lookup/bib/B38890951.
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Thesis (B.Sc.)--University of Hong Kong, 2003."A dissertation submitted in partial fulfilment of the requirements for the Bachelor of Science (Speech and Hearing Sciences), The University of Hong Kong, April 30, 2003." Includes bibliographical references (p. 26-29) Also available in print.
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Diamond, Laura Lyn. "Research-based phonics instruction for beginning readers." CSUSB ScholarWorks, 2000. https://scholarworks.lib.csusb.edu/etd-project/1594.
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Mellen, Brad. "Teaching reading in China : phonics versus whole word /." Thesis, Hong Kong : University of Hong Kong, 2002. http://sunzi.lib.hku.hk/hkuto/record.jsp?B25262774.
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Sharp, L. Kathryn. "Phonics, Phonemic Awareness, and Phonological Awareness—Oh My!" Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/etsu-works/4256.
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Woodhead, Nancy Lynne. "Teaching phonics within a whole language theoretical orientation." CSUSB ScholarWorks, 1992. https://scholarworks.lib.csusb.edu/etd-project/585.
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Cardenas, Jessica M. "Phonics Instruction using Pseudowords for Success in Phonetic Decoding." FIU Digital Commons, 2009. http://digitalcommons.fiu.edu/etd/139.
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This study examined a Pseudoword Phonics Curriculum to determine if this form of instruction would increase students’ decoding skills compared to typical real-word phonics instruction. In typical phonics instruction, children learn to decode familiar words which allow them to draw on their prior knowledge of how to pronounce the word and may detract from learning decoding skills. By using pseudowords during phonics instruction, students may learn more decoding skills because they are unfamiliar with the “words” and therefore cannot draw on memory for how to pronounce the word. It was hypothesized that students who learn phonics with pseudowords will learn more decoding skills and perform higher on a real-word assessment compared to students who learn phonics with real words. Students from two kindergarten classes participated in this study. An author-created word decoding assessment was used to determine the students’ ability to decode words. The study was broken into three phases, each lasting one month. During Phase 1, both groups received phonics instruction using real words, which allowed for the exploration of baseline student growth trajectories and potential teacher effects. During Phase 2, the experimental group received pseudoword phonics instruction while the control group continued real-word phonics instruction. During Phase 3, both groups were taught with real-word phonics instruction. Students were assessed on their decoding skills before and after each phase. Results from multiple regression and multi-level model analyses revealed a greater increase in decoding skills during the second and third phases of the study for students who received the pseudoword phonics instruction compared to students who received the real-word phonics instruction. This suggests that pseudoword phonics instruction improves decoding skills quicker than real-word phonics instruction. This also suggests that teaching decoding with pseudowords for one month can continue to improve decoding skills when children return to real-word phonics instruction. Teacher feedback suggests that confidence with reading increased for students who learned with pseudowords because they were less intimidated by the approach and viewed pseudoword phonics as a game that involved reading “silly” words. Implications of these results, limitations of this study, and areas for future research are discussed.
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Dwyer, Edward J. "Explicit Phonics Instruction with Emphasis on Onsets and Rimes." Digital Commons @ East Tennessee State University, 2000. https://dc.etsu.edu/etsu-works/3734.
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Dwyer, Edward J. "Explicit Phonics Instruction within the Literature Based Reading Program." Digital Commons @ East Tennessee State University, 2001. https://dc.etsu.edu/etsu-works/3733.
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Showalter, Kim S. "The Benefits of Systematic Phonics Instruction With First Grade Students." Defiance College / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=def1281639847.
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Griffin, Crystal Simone. "A comparison of the effectiveness and efficiency of traditional phonics - distributed practice, traditional phonics - massed practice, and incremental rehearsal on kindergarten students' letter-sound correspondence performance." Columbus, Ohio : Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1237210291.
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Swanson, Chad C. "Phonics curriculum-based measurement| An initial study of reliability and validity." Thesis, Alfred University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3619869.
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Early literacy and reading skills are both important predictors of an individual's future success in school and employment settings (Moats, 1999). Moreover, poor reading performance in elementary school has been associated with future conduct problems and juvenile delinquency by age fifteen (Williams, 1994). Research supports the notion that scientifically-based instruction provides all students with the best opportunity to prevent future academic, behavioral, and vocational problems associated with poor reading skill acquisition. The current study investigated the reliability and validity of a curriculum-based measure developed by the current author named Phonics Curriculum-Based Measurement (P-CBM). Two hundred and twenty five first grade students (117 males, 103 females) from two partnering school districts in rural western New York State were included in the study. The results indicated strong alternate forms reliability, inter-rater reliability, and concurrent validity. Upon further validation, P-CBM could be helpful in making screening, progress monitoring, or instructional planning decisions as well as providing pre-referral data to school psychologists who are conducting special education eligibility evaluations for a specific learning disability in reading.
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Ocana, H. Vanessa. "Effects of Extended Explicit Systematic Phonics Instruction on Adult L2 Fluency." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/3032.
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Reading may be viewed as an invisible skill, and some may even consider it a passive skill. However, reading is an active and complex skill. It requires one to use a wide range of skills simultaneously to achieve fluency. Hence, it is crucial to learn and use strategies to master such a complex skill. Today, research states that fluent reading includes using top-down and bottom-up strategies, or an interactive approach, to truly become a fluent reader. In fact, research has shown the effects that all three models have had on students. More specifically, L1 studies have shown positive effects in using phonics instruction (a type of bottom-up model) on students' reading fluency. Although this is true, there has been little research in L2 settings that investigates the effects that phonics instruction has had on L2 learners. It seems that L2 reading curricula focus on teaching top-down strategies in hopes that students implicitly learn bottom-up strategies. In reality, students may need to experience a transitional phase where they explicitly learn phonics and how to decode words in order to become fluent readers. The current study seeks to explore whether implementing extended explicit systematic phonics instruction in an L2 setting facilitates reading fluency. Thus, the goal of this study was to investigate whether extended explicit systematic phonics instruction would affect L2 students' reading fluency in terms of decoding, reading rate and comprehension. Two groups of students participated in this study; an experimental group who received extended explicit systematic phonics instruction and a control group who did not receive the treatment. Two types of exams were administered. One exam indicated that phonics instruction helped students read words accurately, but the second exam illustrated that phonics instruction did not make a difference in decoding, reading rate and comprehension. These results suggest further exploration on the topic.
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Sakr, Hesham. "Towards mid-infrared fibre lasers : rare earth ion doped chalcogenide glasses and fibres." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/33338/.
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This Project is aimed at developing rare earth ion doped chalcogenide glasses targeting mid-infrared (MIR) fibre lasers, emitting in the wavelength region 4 - 5 μm. The work reported in this thesis has two objectives: (i) a study of the Ge-As-In-Se glass system when doped with a single species of rare earth (RE) ions, i.e. praseodymium (Pr3+) or cerium (Ce3+), or when co-doped with two rare earth ion species: Pr3+ and Ce3+, and (ii) a study of the effect of replacing a gallium (Ga) additive with an indium (In) additive on the physical and optical properties of the undoped and Pr3+ doped Ge-As-(Ga/In)-Se glasses and fibres. The MIR, i.e. 3 - 25 μm wavelength, offers to advance many photonics areas including bio-medical imaging spectroscopy for human tissue sensing in vivo for early cancer diagnosis. Low loss RE-ion doped MIR fibre lasers are potential pumps for MIR supercontinuum generation (SCG) sources for a compact MIR broadband device. Also, MIR fibre narrowband lasers offer potential new wavelengths for laser medical surgery. To date, there are no MIR rare earth ion doped glass fibre lasers emitting at wavelengths ≥ 4 μm. Selenide (Se)-based glasses, a member of the chalcogenide glass family, are known for their wide transparency up to 12 μm and good rare earth ion solubility. In the Project, an additive to the Ge-As-Se glass system of indium or gallium is considered to help decluster the rare earth ions and increase their solubility in the as-prepared Pr3+ doped Ge-As-(Ga/In)-Se glasses. However, an indium additive is concluded here to achieve a lower rare earth ion solubility limit than that obtained using the equivalent gallium additive in the Ge-As-(Ga/In)-Se glass systems. On the other hand, the photoluminescent intensity is concluded here to be approximately doubled when using an indium additive in Pr3+ doped Ge-As-In- Se, compared to the analogous gallium glasses. Furthermore, the decay lifetime, at the same emission wavelength of 4.7 μm, is found to be longer in the Pr3+ doped Ge-As-In-Se glasses when compared to the Pr3+ doped Ge-As- Ga-Se glasses. Overall, for a singly-doped Ge-As-In-Se glass system, Pr3+ offer wide photoluminescence spectral emission in the range 3 - 6 μm, which promotes this type of glass fibre as an active source for MIR laser emission in the target range of 4 - 5 μm. However, the photoluminescent decay lifetime, at 4.7 μm, of Pr3+ doped Ge-As-In-Se is concluded to decrease substantially with the number of thermal processes invoked to fabricate the glass-based fibres; a lifetime of 7 - 9 ms measured on the as-prepared fibres is compared to the decay lifetime of 9 - 10.1 ms that were found in the bulk glasses. Alternatively, the addition of Ce3+ in the Ge-As-In-Se glass system is concluded to offer a larger absorption cross-section than that of the Pr3+ in the wavelength range 3.5 - 5 μm. Co-doping the Pr3+ / Ce3+ in Ge-As-In-Se in order to enhance the MIR photoluminescence emission in the range 3 - 6 μm is also investigated. It is concluded that rare earth ions, in particular Ce3+ and / or Pr3+, doped chalcogenide glass fibres based on the Ge-As-In-Se glass system, developed through this Project, are strong candidates towards achieving MIR fibre lasers.
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Helal, Mohamad Anas. "Analysis of the impact of external optical feedback on the performance of high-power and high-brightness laser diodes." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/44996/.
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The main motivation behind this work was to answer the following question: what is the impact of unintentional external optical feedback on laser performance. During the course of this PhD, however, two more questions were raised: how does the spectral external feedback (i.e. intentional feedback from a grating) enhances the spectral performance of the laser? And why does the beam quality of Distributed Bragg Reflector (DBR) tapered lasers degrade at >2.5 times the threshold current? To answer these two questions, new simulations were performed and more results were obtained. The impact of external feedback can be positive or negative. High-brightness lasers are mostly characterised under stand-alone conditions. Nevertheless, high-brightness lasers are almost always operated in external cavity configurations. The external cavity will produce reflections, whether they are intentional reflections off mirrors or gratings, or unintentional reflections off the optics elements. In order to have an accurate prediction of how the high-brightness laser will perform in an external optical system, a modelling tool, which is capable of self-consistently modelling the laser cavity and the fields propagating in the external optical system, is needed. In this work, an external cavity laser simulation tool was developed. This tool consists of an in-house 2.5D laser modelling tool, Speclase; a commercial coherent ray-tracing software, OpticStudio; and an interface software to bidirectionally couple the two different light modelling algorithms used by these tools: finite difference beam propagation (FD-BPM) method and coherent ray-tracing. The author was responsible for: developing the interface software – using Matlab - between Speclase and OpticStudio. Also, the author cooperated with Dr. Kaunga-Nyirenda to modify Speclase so that the coupling between Speclase and OpticStudio modelled the physics correctly. This way the software was able to produce external cavity designs to study the impact of external feedback, intentional and unintentional. The external cavity tool was used to investigate and analyse the impact of parasitic reflections on the performance of high-brightness diode lasers. It was also used to analyse how the Littrow cavity works, which is an example of how intentional feedback is used to improve laser performance. Finally, Speclase was used to investigate why the beam quality of high-brightness DBR tapered lasers degrade at higher power, i.e. at currents > 2.5 times the threshold current. This gave an insight on how the external optical feedback affects the degradation of beam quality. It also helped differentiate between the impact of external feedback coupled to the fundamental mode and to the higher-order vertical modes. This work contributes to the knowledge of how external feedback alters the performance of high-brightness laser diodes. It shows that unintentional feedback can lead to the degradation of output power, power conversion efficiency and beam quality. It also shows the significance of modal discrimination and external cavity coupling coefficients and how they can be used to mitigate the unwanted impacts of external optical feedback. The developed model also contributes to the optimisation of external cavity systems with intentional feedback to get optimum performance. It shows how spectral feedback coupled to the laser cavity can force the laser to favour a specific wavelength that is, by allowing the beam of that wavelength to couple into the RW section, while other wavelengths are spatially filtered out. This work also answers a significant question of why the beam quality of DBR tapered lasers degrade at currents 2.5 times the threshold current, although the back- facet reflectivity is patterned, allowing fields propagating outside the RW to escape the structure. The results show clearly how the patterned back facet reflectivity creates a diffraction of the back-propagating beam which allows the diffracted beam to exit the RW and couple into the taper section, exciting higher-order lateral modes.
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Marinescu, Adrian Cornelius. "Facial thermography for assessment of workload in safety critical environments." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/51730/.
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The fast changing modern world is placing humans in positions we have not had time to evolve and adapt to by natural means, we are thus faced with the task of understanding our abilities and limitations, at both a physical and mental levels and design the world around us with these in mind. This is in line with the aim of the discipline of ergonomics (or human factors), to "optimize human well-being and overall system performance by contributing to the design and evaluation of task, jobs, products, environments and systems" (International Ergonomics Association 2014). This is a large task, spanning multiple other disciplines. The research presented in this thesis is in the area of workload, a concept used to describe the interaction between a task and an operator in terms of demand, perception of task and performance. Many tools and methods have been developed aiming at measuring workload, ranging from subjective measures, primary and secondary task measures, task analysis and physiological measures. The main focus of this research is on physiological methods of assessing workload in safety critical environments. Within the domain of physiological methods for workload assessment, many techniques have been explored over the years and will be presented in the thesis with their advantages and disadvantages. Despite all the efforts made to develop a reliable physiological measurement assessment method for workload, further research is needed; the research presented here focuses on facial thermography as a non-invasive, real-time assessment method for workload, coupled with other physiological measures such as heart rate, breathing rate and pupil diameter. The human physiological response to changes in workload has been examined in three studies which also explore the use of multiple physiological measures as a means of estimating the level of workload. While two of the studies were performed in laboratory conditions having students as participants, a third study was performed in an ecologically valid helicopter simulator in order to test the physiological reactions of highly trained individuals to changes in workload. The results indicate that facial thermography, especially nose area temperatures, as well as pupil diameter respond well to changes in workload and could be used as a noninvasive, real-time method of estimating workload. The flight simulator study revealed that even highly trained individuals have similar responses to changes in demand as the general public. This thesis contributes to the measurement and assessment of workload by using physiological measures, especially facial thermography and presenting the relative contribution of each of the measures in both laboratory and real-life scenarios.
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Chim, Kin-wai. "The effects of phonics teaching on Hong Kong children's English reading development." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B38670410.
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Chim, Kin-wai, and 詹建慧. "The effects of phonics teaching on Hong Kong children's English reading development." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B38670410.
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Basbagill, Abby Renee. "Implementing Visual Phonics With At-Risk Learners Who Are Experiencing Reading Faliure." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1281714437.
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Eicher, Rachel. "A Study of Pre-Service Teacher Efficacy During a Phonics Field Experience." University of Findlay / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=findlay1493814066018961.
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Pirani-McGurl, Cynthia A. "The use of item response theory in developing a Phonics Diagnostic Inventory." Amherst, Mass. : University of Massachusetts Amherst, 2009. http://scholarworks.umass.edu/open_access_dissertations/68/.
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Sharp, L. Kathryn. "Phonological Awareness, Phonemic Awareness, and Phonics; Vocabulary and Comprehension; Content Area Reading." Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etsu-works/4288.
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Garnett, Patricia A. "The combining of explicit phonics and the literature basis of whole language." CSUSB ScholarWorks, 1991. https://scholarworks.lib.csusb.edu/etd-project/586.
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Ramos, Alani. "Teacher Perceptions Regarding the Influence of Secondary Phonics Instruction on Student Reading." ScholarWorks, 2019. https://scholarworks.waldenu.edu/dissertations/7065.
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In a Southern state at a rural high school, leadership staff implemented phonics-based strategies with 9th grade English teachers to improve students' Lexile reading scores. The absence of formative data related to program implementation left stakeholders without a clear understanding of the influence of the phonics-based strategies. The purpose of this qualitative exploratory case study was to obtain formative information from teachers to discern the perceived influence of the phonics-based strategies on reading. Dual coding theory was used to examine teachers' perceptions of the influence of phonics-based strategies on students' motivation, fluency, and self-efficacy. Data were collected using interviews with 9 purposefully selected English teachers who taught Grade 9 students and had at least 1 year of experience using the phonics-based strategies. Data were coded in NVivo and analyzed using thematic analysis. Results indicated that phonics-based strategies were perceived to benefit students' extrinsic motivation and fluency; conversely, teachers perceived the strategies had a limited effect on students' intrinsic motivation and self-efficacy. Implementation of recommendations presented in a white paper based on these findings could result in positive social change by strengthening students' reading and promoting their academic success.
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Leung, Kar, and 梁嘉. "How phonics help primary L2 learners in acquiring reading skills in learning English?" Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B29521853.
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Metcalfe, Marta J. "Teaching phonics skills to young children via the formation of generalized equivalence classes." Virtual Press, 1999. http://liblink.bsu.edu/uhtbin/catkey/1137509.
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An equivalence class exists if the stimuli that comprise the class are related by the properties of reflexivity, symmetry, and transitivity. Through these properties, new behavior that has not been taught emerges. For example, when taught to match Set A stimuli to Set B stimuli and to match Set A stimuli to Set C stimuli, if equivalence classes have formed, subjects will (with no explicit instruction) match Set B stimuli to Set C and Set C stimuli to Set B stimuli. Although equivalence classes have been studied extensively, few studies have considered the application of this technology to educational concerns. The purpose of this study was (a) to determine if phonics skills could effectively and efficiently be taught to young children through the formation of equivalence classes and (b) to investigate the generality of those acquired skills. Using a conditional discrimination procedure, children were taught to match printed letters to dictated phonetic sounds and to match the initial sound of pictured items to dictated phonetic sounds. Test results indicated that equivalence classes had emerged and that generalization did occur. The children could match the initial sound of pictured items to printed letters and vice versa and could name letter sounds and initial sounds of pictured items. During generality testing, each child could identify the initial sound of several novel pictured items and could sound out the letters within the words. However, reading did not occur. Only 1 of 5 children could blend the sounds of letters into recognizable words. A significant difficulty encountered throughout the study was maintaining the children's motivation, possibly due to the children's inexperience in attending to academic tasks. This study did, however, demonstrate that the formation of equivalence classes is an effective and efficient method for teaching phonics and that the formation of generalized equivalence classes is effective in extending those taught relations to novel stimuli.Department of Special Education
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Zaccagnini, Cindy Marie 1960. "The effectiveness of Visual Phonics on the speech production of hearing-impaired children." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277243.
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The effects of intensive multisensory speech training, with and without the use of Visual Phonics techniques, on the speech production of a profoundly hearing-impaired child were studied over a period of 6 weeks. A nine-year-old profoundly hearing-impaired child received 30-40 minutes of intensive speech training daily. Three target phonemes were trained using only multisensory speech training techniques and three target phonemes were trained using multisensory and Visual Phonics training techniques. The subject's productions of target phonemes in trained words and syllables were audio-taped at the end of each training period. Audio-taped productions were rated as correct or incorrect. The number of correct productions in words and syllables were tallied daily. Results show a general trend of improved production for all phonemes trained. There was no differential effect for the training technique used. It was concluded that intensive training, regardless of the technique used, has a positive effect on the speech productions of a profoundly hearing-impaired child.
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Eshiet, Olubusola Inyang. "Synthetic phonics as a tool for improving the reading skills of Nigerian pupils." Thesis, University of Newcastle upon Tyne, 2014. http://hdl.handle.net/10443/2480.
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This study explored whether the synthetic phonics method can improve the reading skills of beginning readers in primary schools in Nigeria using a case study action design underpinned by the sociocultural theory of the Zone of Proximal Development (ZPD) . The official policy on education prescribes English as the language of instruction from the fourth year of school up to the highest educational level in Nigeria. However, research shows that by the fourth year of school, pupils are not equipped with sufficient skills in reading the English language. This poor foundation in the language of instruction has the tendency to affect the academic performance of students for much of their school years resulting in increasing rates of illiteracy in the country. 226 pupils, 9 teachers and 9 schools were included in the study which used intervention and control groups. The teachers for the synthetic phonics group were trained. All pupils were pre-tested before teaching began in the classes. The synthetic phonics classes were taught using the intervention method while the control classes were taught using the traditional method. The synthetic phonics class rooms were regularly observed. After the intervention, the groups were post-tested. Focus groups discussions were conducted with the teachers and interviews with pupils in the synthetic phonics groups. The study found that pupils were more eager to learn in the collaborative and engaging environment offered by the synthetic phonics programme. Also, teachers were more confident to teach English language and they found the synthetic phonics programme very useful and easy to use. Moreover, there was a significant difference in the improveme nt in the reading skills of the pupils in the synthetic phonics groups compared to the pupils in the control groups. The study concluded that synthetic phonics is a possible tool for improving the reading skills of Nigerian pupils.
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Mullins, Amy K. "An Analysis of the Phonics Dance in Two Semi-rural Midwestern Elementary Schools." University of Toledo / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1370199535.
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Kupsky, Dorothy D. "Volunteer Tutors’ and First Graders’ Literacy Learning: Navigating Assumptions, Social Positions, and Phonics." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1275398236.
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Kart, Ayse Nur. "The Qualitative Meta-Analysis of Visual Phonics: A Promising Strategy to Teach Reading." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1492174623195898.
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Moodie-Reid, Lorane Evadney. "Teachers' Perceptions of the Impact of the Jolly Phonics Program on Students' Literacy." ScholarWorks, 2016. https://scholarworks.waldenu.edu/dissertations/2134.
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At 2 primary schools in Western Jamaica, students at the Grade 1 level lacked basic literacy skills of comprehension, letter recognition, letter sounds, and oral communication. The purpose of this qualitative evaluation study was to investigate teachers' perceptions of the Jolly Phonics program implemented to improve students' literacy in Grades 1-3. Guided by Engestrom's activity theory, the effectiveness of the Jolly Phonics approach was examined based on the sociocultural learning theories of Vygotsky, Dewey, and Piaget. The research questions focused on teachers' perceptions of the program's impact on students' literacy improvement and of the strategies used in the Jolly Phonics program. Data collection involved individual interviews with 8 teachers from 2 selected primary schools with a representation of at least 2 teachers from each grade level. Using open coding and thematic analysis, emerging minor and major themes were identified. Themes included (a) positive impact on curriculum and instructional delivery; (b) focus on all students who lacked basic literacy skills; (c) development of phonetic awareness, writing, comprehension, and listening skills; (d) workshops that are stimulating and informative; (e) support from teachers and administrators; and (g) greater focus placed at the lower grades. Overall, the findings indicated that the Jolly Phonics program had a positive impact on struggling readers in Grades 1-3. Implications for positive social change include providing the local district with research-based findings on teachers' perceptions of the impact of and strategies used in the Jolly Phonics Program. The findings can be used to support programming decisions and professional development to improve literacy skills of early and struggling readers.
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Phang, Sendy. "Theory and numerical modelling of parity-time symmetric structures for photonics." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/32596/.
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This thesis presents the study of a relatively new class of photonic structures in-voking Parity-Time (PT)-symmetry. PT-symmetric structures in photonics, as a realisation of PT-symmetric Quantum Mechanics problems, are constructed by a judicious design of refractive index modulation which requires the real part of the refractive index to be an even function and the imaginary part of the refractive index to be an odd function in space. PT-symmetric structures in the form of Bragg gratings, coupled resonators and chain resonators are the main configurations studied in this thesis. These PT-symmetric structures feature a spontaneous symmetry breaking at which interesting wave behaviour such as an asymmetric response depending on the direction of the incident wave, unidirectional invisibility, simultaneous coherent-perfect absorber lasing and localised termination modes are observed; these behaviours are presented in this thesis. Theoretical and numerical studies of these PT-symmetric structures are undertaken which assume realistic material parameters,including material dispersion and material non-linearity. Moreover,in this thesis, potential applications of these PT-symmetric structures are explored. The first part of the thesis considers PT-symmetric Bragg grating structures which are formed by introducing a PT-symmetric refractive index modulation into a Bragg grating structure. If gain/loss dispersion is considered, it is shown that dispersion limits the PT-symmetric operation to just a single frequency. As such spontaneous symmetry breaking can only be achieved by varying the gain/loss parameter. Nevertheless, it is shown that by switching the gain/loss in the system, a switching operation can be achieved by using the PT-Bragg grating at a single frequency. Subsequently,anon-linear PT-Bragg grating is investigated by using a time-domain numerical method, namely the Transmission-Line modelling (TLM) method. For the present work a TLM code is developed from scratch in order to ensure full-flexibility when modelling a dispersive and non-linear material. Using the TLM solver, it is demonstrated that gain/loss saturation is an important material property which should be considered as it may impact the practical applications of a PT-symmetry-based device. In the context of a non-linear PT-Bragg grating (NPTBG), the gain/loss saturation affects the interplay between the PT-symmetric opearation and the Kerr non-linear effect. It is further shown that gain/loss saturation plays a crucial role in securing a stable operation of non-linear PT-based devices. For practical applications, it is demonstrated that a non-linear PT-symmetric Bragg grating offers an additional degree of freedom in their operation,by modulating the gain/loss and the intensity of the input signal,compared to a passive structure which can only be manipulated by the input signal intensity. Two applications based on the interplay of PT-symmetric behaviour and Kerr non-linearity are demonstrated,namely a memory device and a logic-gate device. The second part of the thesis studies PT-symmetric resonator structures as a coupled system and as a periodic chain system. For these studies, a semi-analytical method based on the Boundary Integral Equation (BIE) method is developed and used together with a two-dimensional TLM method. The impact of realistic material parameter on the spectral properties of the structure is again investigated. It is shown that the PT-symmetric behaviour can be observed at a single frequency. Moreover, it is shown that PT-symmetry-like behaviour is observed but with complex eigenfrequencies due to the radiation losses; this is a deviation of the strict definition of a PT-symmetric structure with balanced gain and loss. Lowering lasing threshold by increasing loss in the system is demonstrated; this occurs due to induced early symmetry breaking. The final part of the thesis studies the spectral properties of an infinite and finite chain of PT-symmetric resonators. It is shown that the type of modulation along the PT-chain affects the position of the breaking point of the PT-structure. For a finite PT-chain structure, and for a particular type of refractive index modulation, early PT-symmetry breaking is observed and shown to cause the presence of termination states which are localised at the edge of the finite-chain resulting in localised lasing and dissipative modes at each end of the chain.
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Mudd, Garry William. "III-VI metal chalcogenide semiconductor nanosheets and heterostructures." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/33512/.
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This thesis presents an investigation into the properties of III-VI metal chalcogenide semiconductor nanosheets and demonstrates their capability to enhance graphene-based optoelectronics. Strong quantization effects and tunable near-infrared-to-visible (NIR-to-VIS) photoluminescence emission are reported in mechanically exfoliated crystals of gamma-rhombohedral semiconducting InSe at room temperature. The optical properties of InSe nanosheets differ qualitatively from those reported for transition metal dichalcogenides and indicate a crossover from a direct-to-indirect band gap semiconductor when the InSe nanosheet thickness, L, is reduced to a few nanometres, corresponding to the emergence of a ‘Mexican hat’ energy dispersion for the valence band. At low temperature, radiative recombination of photoexcited carriers bound at native donors and acceptors in nominally undoped InSe nanosheets is observed. A two-dimensional hydrogenic model for impurities is used to describe the increase in binding energy with decreasing L and reveals a strong sensitivity of the binding energy on the position of the impurities within the nanolayer. The application of a magnetic field, B, perpendicular to the plane of InSe nanosheets induces a marked change of the observed optical spectrum. A transfer of intensity from a low-to-high energy component at high B corresponds to an indirect-to-direct band gap crossover, which arises from the Landau quantisation of the in-plane carrier motion and crossover between hole cyclotron orbits centred on closed edges of the valence band. High broad-band (NIR-to-VIS) photoresponsivity is achieved in mechanically formed InSe–graphene van der Waals heterostructures, which exploit the broad-band transparency of graphene, the direct bandgap of InSe, and the favourable band line up of n-InSe with graphene. The photoresponse is dependent on the electron transit time through the InSe layer, as evaluated by a semiclassical model.
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Green, Jonathan. "Visually tracked flashlights as interaction devices." Thesis, University of Nottingham, 2008. http://eprints.nottingham.ac.uk/10604/.
Full textAbstract:
This thesis examines the feasibility, development and deployment of visually tracked flashlights as interaction devices. Flashlights are cheap, robust and fun. Most people from adults to children of an early age are familiar with flashlights and can use them to search for, select and illuminate objects and features of interest. Flashlights are available in many shapes, sizes, weights and mountings. Flashlights are particularly appropriate to situations where visitors explore dark places such as the caves, tunnels, cellars and dungeons that can be found in museums, theme parks and other visitor attractions. Techniques are developed by which the location and identity of flashlight projections are recovered from the image sequence supplied by a fixed camera monitoring a target surface. The information recovered is used to trigger audiovisual events in response to users' actions. Early trials with three prototype systems, each built using existing techniques in computer vision, show flashlight interfaces to be feasible both technically and from a usability point of view. Novel methods are developed which allow extraction of descriptions of flashlight projections that are independent of the reflectance of the underlying physical surface. Those descriptions are used to locate and recognise individual flashlights and support a multi-user interface technology. The methods developed form the basis of Enlighten, a software product marketed by the University of Nottingham spinoff company Visible Interactions Ltd. Enlighten is currently is daily use at four sites across the UK. Two patents have been filed (UK Patent Publication Number GB2411957 and US Patent Application Number 10/540,498). The UK patent has been granted, and the US application is under review.
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Arca, Ahmet. "The design and optimisation of nanophotonic devices using the Finite Element Method." Thesis, University of Nottingham, 2010. http://eprints.nottingham.ac.uk/11169/.
Full textAbstract:
The aim of this thesis is to develop a technique which can be used in the reliable modelling, design and optimisation of practical suboptical wavelength sized photonic/plasmonic devices, which may involve arbitrary geometries on various scales. The technique involves the application of numerical electromagnetic simulation led by theoretical knowledge and physical insight to determine, design and optimise the operating mechanism of such devices. The work in this thesis contains a variety of problems/devices which involve arbitrary structures of different scales. This poses difficulties in both the fabrication and the modelling aspects of the design. The problems range in difficulty from those which can be simply and perfectly described via an analytical solution, to those which would be impractical to design using any other technique. The nature of the problems considered, i.e. the complicated geometry and the range of scales, necessitates the use of a flexible modelling technique. Finite Element Method (FEM) was found to be a valuable tool in the design and optimisation of the devices throughout this thesis, owing its success mainly to its versatility and flexible meshing abilities which allowed its operation in different length scales in an efficient manner. Three nanophotonic/plasmonic devices are considered in an effort to demonstrate the implementation and the application of the developed technique. The devices considered in this thesis demonstrate different challenges in the modelling and design while being of considerable interest in their own right as nanostructures for sensing and measurement. These devices are: A self-calibrated plasmon sensor, a plasmon resonator and an ultrahigh frequency optical acoustic surface wave detector. Whilst the first two devices are important as an application of plasmonics, the third device links the mechanical and optical processes together.
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Inrawong, Prajuab. "Application of PCA and Hough Transform to classify features in optical images." Thesis, University of Nottingham, 2012. http://eprints.nottingham.ac.uk/12520/.
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Viewing fine features of object with optical instruments have become increasingly difficult as the dimensions of many features of interest have become smaller than the traditional optical resolution limit. Examples of these features can be found in semiconductor components and biological tissues. This has caused a move to non-optical methods such as scanning electron and atomic force microscopy techniques, or optical methods combined with signal processing techniques to provide clearer images of samples. This thesis presents a method to increase the resolution of an optical system. This is achieved by using principal component analysis (PCA). Once the PCA measured the object image parameters, the new clearer image can be reconstructed based on these parameters. This process works extremely well. Various aspects of samples measured by the PCA have been investigated, such as the shift of sample, the sample with different sizes, the orientation of sample and the impact of noise. These studies show that the technique is extremely robust, and has huge potential for general usage. The thesis also contains the detail of the Hough Transform technique which was used to provide the initial parameters to the PCA. From the analysis of the technique, it is concluded that the accurate measurement of the technique can be achieved by providing adequate templates of the object image for the system.
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French, Andrew Peter. "Visual tracking : from an individual to groups of animals." Thesis, University of Nottingham, 2005. http://eprints.nottingham.ac.uk/10178/.
Full textAbstract:
This thesis is concerned with the development and application of visual tracking techniques to the domain of animal monitoring. The development and evaluation of a system which uses image analysis to control the robotic placement of a sensor on the back of a feeding pig is presented first. This single-target monitoring application is then followed by the evaluation of suitable techniques for tracking groups of animals, of which the most suitable existing technique is found to be a Markov chain Monte Carlo particle filtering algorithm with a Markov random field motion prior (MCMC MRF, Khan et al. 2004). Finally, a new tracking technique is developed which uses social motion information present in groups of social targets to guide the tracking. This is used in the new Motion Parameter Sharing (MPS) algorithm. MPS is designed to improve the tracking of groups of targets with coordinated motion by incorporating motion information from targets that have been moving in a similar way. Situations where coordinated motion information should improve tracking include animal flocking, people moving as a group or any situation where some targets are moving in a correlated fashion. This new method is tested on a variety of real and artificial data sequences, and its performance compared to that of the MCMC MRF algorithm. The new MPS algorithm is found to outperform the MCMC MRF algorithm during a number of different types of sequences (including during occlusion events and noisy sequences) where correlated motion is present between targets. This improvement is apparent both in the accuracy of target location and robustness of tracking, the latter of which is greatly improved.
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O'Donnell, Matthew David. "Tellurite and fluorotellurite glasses for active and passive fibreoptic waveguides." Thesis, University of Nottingham, 2004. http://eprints.nottingham.ac.uk/10089/.
Full textAbstract:
Glasses systems based on TeO2-ZnO-Na2O (TZN), TeO2-WO3, and TeO2-Na2O-ZnF2 are reported here, with a number of other components added (PbO, GeO2, Nb2O5, Bi2O3, Er2O3, Yb2O3, PbF2, and ErF3). Glass formation was shown for the first time, to this author's knowledge, in the ternary system (90-x)TeO2-10Na2O-xZnF2 for x = 5 to 30 mol. %. Glass stability (Tx-Tg) was found to increase with ZnF2 addition, reaching a plateau of around 161oC at x = 25 mol. %. This could be due to competition of various phases to crystallise (NaZnF3 and Zn2Te3O8) as the eutectic is approached, with fluoride addition. These glasses are the most stable ZnF2 containing tellurite compositions reported to date, to the author's knowledge. As-received ZnF2 batch material was shown to contain a significant proportion of Zn(OH)F, identified by XRD. The as-received ZnF2 was fluorinated with (NH4)HF2, which produced a substantially more phase pure powder, with oxygen levels reduced from around 13.2 to 3.1 at. % from XPS spectra. By calculation from the O1s XPS peaks, the proportion of Zn(OH)F was reduced in the powders from 39.7 to 9.4 mol. %. A number of absorption bands in the infrared were identified by FTIR for the TeO2 -ZnO-Na2O glasses due to intrinsic lattice vibrations (visible in a 0.2 mm sample), and extrinsic impurity absorption, including: free OH (around 3.0 microns, 3300 cm-1), weakly hydrogen-bonded OH (around 3.3 microns, 3060 cm-1), and strongly hydrogen-bonded OH (around 4.8 microns, 2090 cm-1). For the series (90-x)TeO2-10Na2O-xZnF2, mol. %, x = 5 to 30 mol. % melted for 2 hours as bulk glasses, OH bands at 2900 cm-1 were reduced in intensity with ZnF2 addition due to self drying of the melt, from around 0.12 cm-1 (120 dB.m-1) for x = 5 mol. %, to around 0.02 cm-1 (20 dB.m-1) for x > 15 mol. %. Melting time also had a significant effect on drying of this series, with the loss at 2900 cm-1 reduced by two orders of magnitude when increased from 1 hour (around 705 cm-1, 705 dB.m-1) to 2 hours (0.01 cm-1, 10 dB.m-1). Refractive index of the series (90-x)TeO2-10Na2O-xZnF2, mol. %, x = 5 to 30 mol. % decreased linearly with ZnF2 addition, from 2.02 (x = 5 mol. %) to 1.85 (x = 30 mol. %), as the fluoride and zinc are less polarisable than oxygen and tellurium. Cohen-Grest viscosity modelling was used to predict the fibre drawing temperature (around 330oC, corresponding to a viscosity of 10^4.5 Pa.s), and fragility of the fluorotellurite core / clad pair (20 / 25 mol. % ZnF2), occurring at least 60oC < Tx. Fragility of these glasses was predicted to lie between oxide tellurite glasses (stronger) and fluorozirconate glasses (more fragile). Increasing melting time and fluorination resulted in a significant decrease in OH bands in the 700 nm to 2.5 micron region for unstructured 70TeO2-10Na2O-20ZnF2 mol. % fibre, from around 40 to 4 dB.m-1 at 2.5 microns as melting time was increased from 3 to 10 hours. Fibre optical loss for the 10 hour melt was relatively flat (around 5 dB.m-1) over the entire 700 nm to 2.5 micron region.
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Dong, Peiliang. "On-chip ultra-fast data acquisition system for optical scanning acoustic microscopy using 0.35um CMOS technology." Thesis, University of Nottingham, 2009. http://eprints.nottingham.ac.uk/10667/.
Full textAbstract:
Optical Scanning Acoustic Microscopy (OSAM) is a non-contacting method of investigating the properties and hidden faults of solid materials. This thesis presents an ultra-fast data acquisition system (DAQ) which samples and digitises the output signal of OSAM. The author's work includes the design of the clock source and the sampler, and integration of the whole system. The clock source is a unique pulse generator based on a 2.624GHz PLL with a Quadrature VCO (QVCO), which is able to generate 4 clock signals in accurate quadrature phase difference. The pulse generator used the 4-phase clocks to provide control pulses to the sampler. The pulses were carefully aligned to the clock edges by digital logic, so that jitters were reduced as much as possible. The required short time delay for the sampler was also provided by the pulse generator, and this was implemented by a smartly-controlled switch box which re-shuffles the 4-phase clocks. The presented sampler is a novel 10.496GSample/s Sub-Sampling Sample-and-Hold Amplifier (SHA). The SHA sampled the input, and transformed its spectrum down to a low-frequency range so that it can be digitised. Charge-domain sampling strategy and double differential switches were both developed in this circuit to significantly improve the sampling speed. The periodicity of the system input was exploited in repetitive sampling to reduce the noise. These designed modules were integrated into a DAQ for a 2x8 sensor array. A pseudo-parallel scanning strategy was presented to minimise the power consumption, and a current-based buffer was applied to deliver the control pulses into the array. The DAQ was implemented on-chip in a low-cost 0.35um standard CMOS process. The measurement results showed that the DAQ successfully achieved a sampling rate more than 10GS/s, with a maximum output resolution of approximately 6 bits.
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Pui, Boon Hean. "CMOS optical centroid processor for an integrated Shack-Hartmann wavefront sensor." Thesis, University of Nottingham, 2004. http://eprints.nottingham.ac.uk/13846/.
Full textAbstract:
A Shack Hartmann wavefront sensor is used to detect the distortion of light in an optical wavefront. It does this by sampling the wavefront with an array of lenslets and measuring the displacement of focused spots from reference positions. These displacements are linearly related to the local wavefront tilts from which the entire wavefront can be reconstructed. In most Shack Hartmann wavefront sensors, a CCD is used to sample the entire wavefront, typically at a rate of 25 to 60 Hz, and a whole frame of light spots is read out before their positions are processed. This results in a data bottleneck. In this design, parallel processing is achieved by incorporating local centroid processing for each focused spot, thereby requiring only reduced bandwidth data to be transferred off-chip at a high rate. To incorporate centroid processing at the sensor level requires high levels of circuit integration not possible with a CCD technology. Instead a standard 0.7J..lmCMOS technology was used but photodetector structures for this technology are not well characterised. As such characterisation of several common photodiode structures was carried out which showed good responsitivity of the order of 0.3 AIW. Prior to fabrication on-chip, a hardware emulation system using a reprogrammable FPGA was built which implemented the centroiding algorithm successfully. Subsequently, the design was implemented as a single-chip CMOS solution. The fabricated optical centroid processor successfully computed and transmitted the centroids at a rate of more than 2.4 kHz, which when integrated as an array of tilt sensors will allow a data rate that is independent of the number of tilt sensors' employed. Besides removing the data bottleneck present in current systems, the design also offers advantages in terms of power consumption, system size and cost. The design was also shown to be extremely scalable to a complete low cost real time adaptive optics system.
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Chandesa, Tissa. "Visual tracking : detecting and mapping occlusion and camouflage using process-behaviour charts." Thesis, University of Nottingham, 2013. http://eprints.nottingham.ac.uk/13444/.
Full textAbstract:
Visual tracking aims to identify a target object in each frame of an image sequence. It presents an important scientific problem since the human visual system is capable of tracking moving objects in a wide variety of situations. Artificial visual tracking systems also find practical application in areas such as visual surveillance, robotics, biomedical image analysis, medicine and the media. However, automatic visual tracking algorithms suffer from two common problems: occlusion and camouflage. Occlusion arises when another object, usually with different features, comes between the camera and the target. Camouflage occurs when an object with similar features lies behind the target and makes the target invisible from the camera’s point of view. Either of these disruptive events can cause a tracker to lose its target and fail. This thesis focuses on the detection of occlusion and camouflage in a particle-filter based tracking algorithm. Particle filters are commonly used in tracking. Each particle represents a single hypothesis as to the target’s state, with some probability of being correct. The collection of particles tracking a target in each frame of an image sequence is called a particle set. The configuration of that particle set provides vital information about the state of the tracker. The work detailed in this thesis presents three innovative approaches to detecting occlusion and/or camouflage during tracking by evaluating the fluctuating behaviours of the particle set and detecting anomalies using a graphical statistical tool called a process-behaviour chart. The information produced by the process-behaviour chart is then used to map out the boundary of the interfering object, providing valuable information about the viewed environment. A method based on the medial axis of a novel representation of particle distribution termed the Particle History Image was found to perform best over a set of real and artificial test sequences, detecting 90% of occlusion and 100% of camouflage events. Key advantages of the method over previous work in the area are: (1) it is less sensitive to false data and less likely to fire prematurely; (2) it provides a better representation of particle set behaviour by aggregating particles over a longer time period and (3) the use of a training set to parameterise the process-behaviour charts means that comparisons are being made between measurements that are both made over extended time periods, improving reliability.
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Leighton, Jonathan M. "GPS and PSI integration for monitoring urban land motion." Thesis, University of Nottingham, 2010. http://eprints.nottingham.ac.uk/11353/.
Full textAbstract:
Urban ground motion due to natural or man-made geological processes is an issue of major importance for local authorities, property developers, planners and buyers. Increased knowledge of this phenomena would benefit all involved but the measurement techniques in common use have either spatial or temporal inadequacies. A technique known as Persistent Scatterer Interferometry (PSI) has been developed which can map ground motion to high precision over large areas with a temporal scale measured in years. PSI takes advantage of the high number of Synthetic Aperture Radar (SAR) images available to mitigate the atmospheric effects that inhibit standard Interferometric SAR (InSAR) techniques. This however involves assumptions about the nature of atmospheric variability, such as its randomness over time, or its spatial extent. In addition, little is known about the Persistent Scatterers (PS) themselves and PSI is only able to provide results relative to a reference PS. The reference PS point is often arbitrarily chosen and may itself be in an area undergoing ground motion, thus adding a degree of ambiguity to any relatively derived motion. The purpose of this work is to investigate possible solutions to these shortfalls and quantify any improvements made. A corner reflector network is established in the Nottingham area of the UK. A data archive is collated over three years containing Global Positioning System (GPS) data at the corner reflector sites, data from surrounding Continuous GPS (CGPS) sites and levelling data. Due to conflicts with the European Space Agency (ESA) Environmental Satellite (ENVISAT), there were insufficient SAR images to com- pute a fully integrated corner reflector PSI study. Instead, the project focussed on atmospheric correction of PSI results using absolute ZWD estimates. Zenith Wet Delay (ZWD) estimates are derived from a Precise Point Positioning (PPP) GPS processing method which does not rely on a network of ground stations and therefore produces absolute ZWD estimates which are less prone to biases and noise. These are interpolated across a PSI study area and used to mitigate the long wavelength effects of atmopheric water vapour in the PSI differential interferograms. The corrected PSI results are then compared to uncorrected results, GPS derived motion and levelling data. Results between the ZWD corrected PSI study and the uncorrected study show statistical improvements in some areas and reductions in others. Correlation factors between double-differenced levelling observations and double-differenced PSI results improve from 0.67 to 0.81. PSI deformation rates also show improvement when compared to GPS deformation rates, although some results do not satisfy statistical tests.
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Oladeji, Ayodele. "Numerical and experimental investigation of novel materials for laser and amplifier operations." Thesis, University of Nottingham, 2015. http://eprints.nottingham.ac.uk/31458/.
Full textAbstract:
One of the most exciting areas of research in optics is rare-earth doped glasses and fibres with capacity for near-infrared to mid-infrared operations. In particular, there is great interest in optimising parameters like ion concentration, fibre length/geometry, and pump conditions for applications in photoluminescence, amplification and lasing. Round trip investigation from material fabrication, experimental setup and actual device can be laborious, expensive and come with some uncertainties. Some of these uncertainties are accurate identification of ion-ion interactions, impact of such interactions on device performance, correct extraction of phenomenological material properties and the prediction of combination of properties with numerical methods. In this thesis, the spectroscopic behaviour of rare-earth doped materials are theoretically studied via numerical simulations and experimentally verified. The models developed are applicable to steady-state and transient behaviour of rare-earths under different excitation conditions. For the simulation, a couple of spectroscopic parameters are needed which have to be obtained in advance from bulk glasses. Parameters like radiative and non-radiative lifetimes are calculated by complementing theoretical analysis with a few experimental measurements. The first part of the research concentrates on the study of ion-ion interactions in different concentrations of erbium doped sol-gel SiO2 prepared by the sol-gel method. The work includes continuous-wave (CW) and pulsed excitation spectroscopic measurement on the glasses that provide data for the model. These measurements together with the rate-equation modelling are used to obtain a physical understanding of the processes responsible for the fluorescence features observed. A particle swarm optimisation technique was used to predict the values of the ion-ion interactions. The behaviour of the 488 nm and 800 nm excitations were consistent with the predictions of the model. Indeed, the agreement between the calculated photoluminescence and the measured emission indicates that the six important processes that influence the ion-ion interactions in the bulk material have been correctly identified and included. With this model of photoluminescence at hand, it was possible to extend it to laser or amplifier configurations. Subsequently, erbium doped ZBLAN glass fibre with lower phonon energy were explored for lasing in the mid-infrared for application to 2.73 µm high-power delivery for tissue surgery. Accurate laser characteristics were predicted for two different designs, including the ultimate thermal designs. Optimum boundary conditions of mirror end-facet reflectivity, fibre length and effects of modelling parameters were addressed. The study is complimented with experimental data of double-clad fibre and the results reported were a clear documentation of the design of erbium doped ZBLAN fiber laser. Finally, the potential of P r3+ doped chalcogenide (GeAs(Ga/In)Se) glass for photoluminescence and lasing at 4.73 µm is studied. This is to answer the research question - Can we extract the spectroscopic parameters and also model the superior property of these novel glasses?. The laboratory facilities and availability of experimental data were decisive in the choice of praseodymium ions as well as inclusion of Gallium or Indium for this part of the research. The superior characteristics of Indium over Gallium for hotoluminescence and consequently device characteristics were studied with the aid of a rate equation model. The phenomenon of photon reabsorption in the chalcogenide fibres were also simulated and verified with experiment. The work has produced a comprehensive numerical model for the simulation of photoluminescence in P r3+doped selenide based chalcogenide glass and fibre from NIR to mid-IR especially in the Gallium and Indium based analogues.
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Arnold, Shelley Susannah. "Reading Impairments In Children With Neurofibromatosis Type 1: Profiling and Treatment." Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/20218.
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Reading difficulties are reported in the majority of children with neurofibromatosis type 1 (NF1) and have significant functional impacts. Primary aims of this thesis were to i) examine the reading profile of children with NF1, from preschool to school-age, and ii) investigate the effectiveness of a reading intervention. Three studies were conducted. Study 1 examined the preliteracy abilities of young children (5-6 years) with NF1 compared to controls. Results indicated that the performance of children with NF1 was significantly poorer than controls in all preliteracy domains. Study 2 investigated the reading profile of school-age children (7-12 years) compared to controls. Results revealed that the performance of children with NF1 was significantly poorer than controls on all literacy measures. Study 3 examined the efficacy of a computerised phonics training program for school-age children with NF1 and reading difficulties. Following treatment, children demonstrated significant improvement on literacy outcomes. Collectively these studies contribute to our understanding of the reading profile of children with NF1. Findings show that weaknesses in phonological processing and letter-sound knowledge are common in children from preschool to school-age indicating these deficits may underlie the reading difficulties experienced by children with NF1. Further these weaknesses can be detected as early as preschool age. Findings also indicate that reading deficits in children with NF1 can be successfully treated by teaching letter-sound knowledge. These findings can be used to inform clinical practice. The implementation of preliteracy screening for all young children and early intervention, may result in a greater success rate of remediation, decrease the likelihood of later literacy difficulties and contribute to significant improvements in the quality of life for children with NF1.
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Lundin, Rebecca, and Marie Sveningsson. "Den viktiga grunden : En studie om läs-och skrivinlärning." Thesis, Linnéuniversitetet, Institutionen för utbildningsvetenskap (UV), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-32513.
Full textAbstract:
Syften med studien är att undersöka vilka läs- och skrivinlärningsmetoder verksamma lärare använder sig av samt vilken syn lärarna har på läs- och skrivinlärning. Våra frågeställningar berör även de faktorer som påverkar läs- och skrivinlärningsprocessen. Studien är en kvalitativ intervjustudie där fyra verksamma lärare har deltagit. Intervjuerna är gjorda i tre olika kommuner i södra Sverige. Resultatet visar att lärarna använder sig till största del av Phonics metoden men med inslag av andra metoder. Lärarna tryckte på vikten av att kunna alternera mellan olika metoder för att kunna tillgodose alla elevers behov. Resultatet visar även att samtliga lärare betonade att läs- och skrivinläringen är en viktig grund för elevers kommande skolgång.
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Gradisic, Lejla, and Maria Lundin. "Barns läsutveckling : På vilket sätt påverkas den vid användandet av Phonics respektive Whole language?" Thesis, Linköpings universitet, Institutionen för beteendevetenskap och lärande, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-118897.
Full textAbstract:
Barns läsutveckling har länge delat upp forskare och lärare i två läger. The reading war i USA spred sig över världen under 1970-talet och påverkade även lärare och forskare i Sverige. Debatten gällde om elever skulle fortsätta undervisas genom att lära sig alfabetets bokstäver och tillhörande språkljud eller om det var mer effektivt att använda sig av en helordsmetod. Syftet med denna konsumtionsuppsats har varit att undersöka skillnader i barns läsutveckling vid användandet av Phonics och Whole language och hur dessa skiljer sig mellan olika ortografier. Vi har även analyserat tidigare forskning där de kombinerat dessa två metoder.Denna vetenskapliga litteraturstudie har genomförts genom att jämföra resultat av tidigare forskning. Resultaten i dessa studier har sedan granskats och analyserats och sedan sammanställts utifrån våra frågeställningar och vårt syfte. Resultaten visar att det uppstår vissa skillnader vid barns tidiga läsning. Elever som undervisas med Phonicsmetoden utvecklar en större fonologisk medvetenhet och avkodar orden bättre än de elever som undervisats med Whole language. Vidare visar resultaten att de elever som undervisats med Whole language får en bättre läsförståelse. Gällande läsningen visade eleverna liknande resultat och skillnaderna låg i avkodning av okända ord samt läsförståelsen.Det viktigaste vid läsundervisningen är dock att läraren är kompetent och besitter en stor kunskap om den metod hen använder sig av.
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Song, Li-Chieh, and 宋立潔. "A Comparison of Two Phonics Approaches-- The Revelational Phonics Approach and Analytic Phonics Approach." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/95936812730008497442.
Full textAbstract:
碩士國立東華大學
英美語文學系
105
The purpose of this study was to compare two phonics approaches— the Analytic Phonics Approach (the APA) and Revelational Phonics Approach (the RPA). The APA teaches from a “implicit” perspective, while the RPA is based on a “explicit” belief. In this study, the 36 participants were third grade Chinese L1 pupils with the same learning baseline. Nineteen of the participants received the APA and the other 17 students received the RPA. Both approaches were conducted for 12 weeks, including pretest and posttests, which were word reading and oddity tasks. The purpose of word reading tasks was to evaluate beginning readers’ knowledge of the alphabetic principle while oddity tasks were meant to evaluate students’ phonological awareness. The results showed: (1) both groups made progress in the post-intervention word reading test, but the RPA group outperformed the APA group. The RPA seemed to develop learners’ knowledge of the English alphabetic principle more effectively; (2) while both groups performed better on the post-intervention oddity test, the improvement was not statistically significant.
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Chou, Yen-Chun, and 周彥君. "Textbook Phonics: Does it Match Teachers’ Perspectives on Phonics Instruction?" Thesis, 2012. http://ndltd.ncl.edu.tw/handle/68007996958849054732.
Full textAbstract:
碩士臺北市立教育大學
英語教學系碩士班
100
The purpose of this study was to investigate elementary school English teachers’ perspectives on phonics instruction and on the phonics teaching contents of their English textbooks. Then the findings were further compared, contrasted, and inductively analyzed in order to find out, based on elementary school English teachers’ perspectives, if the design of the phonics teaching contents of their English textbooks is consistent with their perspectives on phonics instruction. The instruments used in this study were questionnaire survey and interviews. The participants were elementary school English teachers whose schools used the same series of English textbooks from the third grade to the sixth grade. The questionnaire respondents included 174 teachers. Among the 174 respondents, six of them who held different perspectives and were willing to be interviewed were invited as interviewees. The results of this study indicated that, in terms of their perspectives on phonics instruction: 1. Most elementary school English teachers know that the main purpose of phonics instruction is to teach letter-sound correspondences, and that phonics instruction benefits students’ ability to spell words, recognize words, pronounce sounds, read, and memorize words. 2. Most elementary school English teachers know that phonics instruction cannot completely replace K.K phonetic symbols. Phonics should be introduced at elementary phase. However, some elementary school English teachers still cannot distinguish phonics from phonetics. 3. Most elementary school English teachers’ perspectives on how phonics should be taught are in accordance with guidelines as suggested in previous research. 4. Most elementary school English teachers think that both traditional and contemporary phonics approaches should be used when teaching phonics. 5. Most elementary school English teachers think they have sufficient understanding about phonics, but some of them still want to know more about phonological awareness and how to teach phonics. In terms of their perspectives on the design of the phonics teaching contents of English textbooks: 1. Most elementary school English teachers think that their English textbooks provide suitable teaching sequence, review sections, appropriate keywords of letter-sound correspondences, and onset and rimes. 2. Some elementary school English teachers think their English textbooks do not provide enough phonological awareness exercises; exercises in which students can apply their phonics knowledge; and review section which integrate what studemts have learned before. To sum up, the design of the phonics teaching contents of English textbooks in general meets elementary school English teachers’ teaching needs. However, there are still a few things that need to be improved. For example, the phonics teaching contents are irrelevant to other exercises in the textbooks; there are not enough phonological awareness exercises, syllable and stress exercises, or exercises for students to read unfamiliar words and review what they have learned. Thus, English textbooks should modify the design of the phonics teaching contents according to the findings in this study in order to meet English teachers’ teaching needs.