Doctor of Philosophy (Ph.D.)

Permanent URI for this collection

https://hdl.handle.net/10497/18

Browse

Now showing 1 - 20 of 528

Open Access
A multiple-case study on school support systems for low-performing primary students of Chinese language
(2024)
Chau, Sook Kuan
Bilingual education has always been a cornerstone of Singapore’s education. Chinese Language (CL) is offered as a compulsory Mother Tongue Language (MTL) subject in all Singapore mainstream schools to students of Chinese ethnicity. With the intergenerational change of home language environment and increasingly diversified profile of CL students, supporting low-performing students has become an area of concern in the teaching of CL. In response, the Ministry of Education (MOE) implemented initiatives such as the Chinese Language Modular Curriculum in 2007 for Primary 2 to 6 levels and the Mother Tongue Support Programme (MTSP) in 2021 for Primary 3 and 4 levels. Yet, even with these initiatives, a structured learning support programme for lower primary low-performing students seems lacking, schools are expected to exercise their own discretion on how to customise intervention practices and support programmes for Primary 1 and 2 low-performing students of CL, and students excluded from the MTSP.
Therefore, this study aims to gain a deep understanding on how schools customise school-based support systems for the learning of low-performing students of CL, and to provide an in-depth description regarding the good practices that work together to create conducive conditions for the learning and development for these students.
To define good practices, this study uses a theoretical perspective based on Deci and Ryan’s self-determination theory (SDT) (1985, 2004) to discuss the need-supportive and need-thwarting factors within the schools practices. SDT postulates that humans are inherently motivated to learn and internalise knowledge, and this motivation will be fostered and sustained by supporting the basic psychological needs for autonomy, competence and relatedness. This study uses a multiple-case study design to answer two research questions:
1) How do schools support the learning of low-performing students of Chinese Language? What models, approaches, and strategies do schools/teachers use?
2) How do these models, approaches, and strategies support the psychological needs of low-performing students of Chinese Language? Why?
This study collects and analyses interview and observational data from three participating schools, elaborates on (i) the details of school support systems, focusing on conceptualisation, implementation, effectiveness and limitations of the various components of the systems, highlighting similarities and differences in several common procedural steps, including considerations on strengthening students' learning attributes, identification of low-performing students, deployment of teachers, and practices adopted by teachers in the classroom; (ii) how these nuances impact the support of the basic psychological needs of low-performing CL students, detailing the common need-supportive and need-thwarting factors and discussing their impacts.
This study provides a rich repertoire of data for school leaders, teachers and researchers seeking insights into the elements of an effective support system for low-performing students in Mother Tongue Languages and other subjects. Future studies can replicate this research across different levels, subjects, and school settings, and further empirical studies employing alternative measures can be conducted to assess the impact of each classroom condition and teacher behaviour on the psychological needs and motivation of low-performing students, providing a more substantive dimensions to the findings and phenomenon discussed in this study.
112 372
Open Access
A Rasch investigation on the relationship between distributed leadership practices and cultural work values of middle managers in Singapore schools
(2024)
Lim, Simon Qing Wei
In the contemporary school climate, the intricacies of school functions and operational demands have led to the evolution of leadership practices. School leaders can no longer effectively lead the school fraternity on their own, but instead, they need to involve other incumbents particularly those in the middle leadership positions, to meet the growing demands. From an in-depth review of the extant leadership literature such as distributed leadership, it has unfortunately revealed the dearth of research in attempting to understand how middle managers would perceive leadership practices especially in an Asian context (e.g., Singapore). Notwithstanding that cultural factors may influence leadership practices, very little is known about how distributed leadership is practised in non-Western contexts. Furthermore, distributed leadership appears to be an elusive construct which contains conceptualization, operationalization, and methodological issues. To address these concerns, this study is set to establish a better understanding of distributed leadership practices by determining its factor structure and to examine whether the dimensions of distributed leadership practices may be related to Singapore middle managers’ cultural work values. From the comprehensive analysis of distributed leadership literature, six plausible dimensions of distributed leadership practices were identified, namely: empowerment, shared decisions, collective engagement, leadership development, shared vision, and supportive culture. Hofstede’s cultural work values framework was adopted as a guide to investigate the relationships between the two constructs. The dimensions include individualism versus collectivism, high versus low power distance, high versus low uncertainty avoidance, assertiveness versus consideration, long-term versus short-term orientation, and indulgence versus restraint.
Using these dimensions as theoretical ‘signposts’, the study began by interviewing 20 middle managers individually to obtain nuanced understanding on their distributed leadership practices and cultural work values. These insights were subsequently used to guide the development of two rating scales for measuring middle managers’ perceptions of distributed leadership and cultural work values. A total of 123 middle managers responded to the survey, and their responses were used to establish the factor structure of distributed leadership practices and its relationship with cultural work values.
The analyses show that distributed leadership construct is indeed made up of six factors, namely: measured empowerment, shared decisions, collective engagement, leadership development, shared vision, and supportive culture. These distributed leadership dimensions were found to be significantly correlated with five cultural work values which comprise individualism versus collectivism, high versus low power distance, long-term versus short-term orientation, high versus low uncertainty avoidance, and indulgence versus restraint. Interestingly, Singapore middle managers would engage in distributed leadership practices differently from what were asserted in Western literature. Such disparities can be explained by cultural differences between societies. As cultural work values are always evolving because of globalization, it is not surprising that middle managers did not indicate cultural work values that are on one extreme end of the continuum. Instead, they indicated cultural work values that exist along the continuum. To a large extent, they do tend to promote collectivism among staff and respect for hierarchy, while acknowledging the need for strategic pragmatism to ensure the effectiveness and efficiency of school administration in Singapore.
118 362
Restricted
Achievement of gifted adolescents in Singapore: the effects of perception, creative-thinking ability and an intervention programme "knowledge/volition/action"
(1996)
Teo, Chua Tee
This study hypothesizes that intellectually gifted adolescents in the Gifted Education Programme (GEP) who had greater preferences for perception and creative-thinking would tend to perform less well academically owing to a lack of volition, and that an education intervention encompassing self-knowledge, volition, consultation, time and stress management would result in significant improvements in achievement. The relationships between academic achievement, perception and creative-thinking ability were first ascertained using linear regression analyses. Gifted pupils who were interested in self-development were then randomly selected and randomly assigned to experimental and control groups. Experimental and control subjects were matched by age, sex, school, class, race, socio-economic status, creative-thinking ability, academic and non-academic achievement were reported using paired t tests, single-subject time series designs and interviews with subjects. Atypical cases of subjects who evinced remarkable, moderate and low personal gains were featured in case studies.

Subject in Phase I of the study were all (N=239) Secondary One GEP pupils in three independent schools. The experimental study in Phase II involved 57 experimental subject and 57 controls. The academic progress of six experimental subjects, three males and three females, were longitudinally studied with single-subject time series plots. Three of the six subjects were selected for case studies. The Myers-Briggs Type Indicator (Form G) (MBTI) (Myers, 1976, 1977) was used to measure preferences for perception, sense perception, intuitive perception and judgment. The How Do You Think (Form E) (HDYT) (Davis, 1977) was used to assess creative-thinking ability. The educational intervention programme, "Knowledge/Volition/Action", was comprised of five one-hour modules. Self-knowledge, volition, consultation, time and stress management were taught to subjects in an interactive manner. Parents and teachers of the subjects were also interviewed for triangulation of qualitative data.

Results of linear regressions indicated a significant but negative correlation between academic achievement of gifted adolescents and their perception scores; a significant positive correlation of academic achievement with judgment; and a negative but non-significant correlation between academic achievement and creative-thinking ability. Creative-thinking ability, in turn, was found to be significantly and positively correlated with perception. Multiple regression models revealed that approximately 14% of academic achievement and 48% of creative-thinking ability were explainable by MBTI variables.

The intervention programme was found to be effective in augmenting non-academic achievement of the experimental group. Specifically, the non-academic achievement of gifted adolescents who were "perceptives" was enhanced. No group effect was detected with regard to academic achievement. Visual inspection for changes in academic progress of subjects in single-subject studies between the baseline and the intervention phases indicated that individual subjects demonstrate that individual subjects had benefited from the intervention programme in different ways and to different degrees. The general feedback was that the intervention programme had benefited them more in the area of personal and social enrichment rather than academic studies. Findings in the case studies indicate that the ability to activate volition may be critical in overcoming procrastination and in bringing about achievement-oriented behaviour.
289 52
Restricted
An acoustic investigation of segmentals and rhythm in Philippine English
(2022)
Irwan Shah Shahruddin
Even though there has been much research on Philippine English (PhilE) pronunciation, previous studies have mainly relied on impressionistic observations. There is a general paucity in the acoustic investigation of pronunciation in PhilE. In addition, while current studies adopt the lectal continuum in the description of PhilE phonetic features, it has been suggested that even within a similar lect of speakers, differences in pronunciation might still exist.

The present study attempts to fill these gaps by providing an acoustic investigation of segmentals and rhythm of PhilE. To achieve this, it aims to fulfil three main objectives. First, it contributes to the literature on English in the Philippines by presenting a comprehensive review of phonological features of Philippine English. Second, it attempts to investigate acoustically three aspects of pronunciation of PhilE, namely vowels, consonants and rhythm, to validate the phonological features identified in previous studies while hoping to uncover new phonetic features of PhilE. Third, it attempts to find out whether differences in pronunciation features exist between two groups of educated PhilE speakers, studying in two universities in Manila, namely a private university and public university. The thesis begins by introducing the background to the study, providing an overview of PhilE as a variety and reviewing relevant literature pertaining to the phonology of PhilE. It then reviews the literature on segmentals and rhythm, including acoustic characteristics of vowels, consonants and rhythm. Following that, it describes the details the methodology of the study, namely data collection, measurement of data and dealing with reliability issues surrounding data measurement. The next few chapters entails the conduct of acoustic investigation, and an analyses and findings on the investigation of PhilE pronunciation in terms of vowels, consonant and rhythm. Finally, it concludes the study by providing the summary, discussion and implications of the study.

While the present study presents an acoustic description of the vowels, consonants and rhythmic patterning of PhilE, differences between speakers from the private university and public university are not as clear-cut. In terms of vowels, differences can be seen in the quality and duration of vowel pairs from the two groups of PhilE speakers. With regard to consonants, the comparison of aspiration in stop consonants show mixed results, while rhoticity is consistent in non-prevocalic /r/ for both groups of speakers. As for rhythm, the rhythmic indices reveal the rhythm of both groups of PhilE speakers being more stress-based when compared to a syllable-based variety.

The present study also discusses phonetic features of PhilE that surface in the study, as well as some contributions and implications of the study. A previous study has implied that the acrolectal speakers of PhilE are not monolithic. Based on the findings of this study, an attempt to position PhilE in the Kachruvian framework and Schneider’s dynamic model of the evolution of postcolonial Englishes is made. In Schneider’s framework, the PhilE phonetic features seem to be stabilized at Phase 4.
393 150
Restricted
An acoustic investigation of segmentals and rhythm in Yunnan English
(2015)
Ao, Ran
There is a general paucity of acoustic investigation of pronunciation of English learners in Mainland China. The few studies that exist have mainly relied on auditory or impressionistic data analysis. Furthermore, most of these studies have focused on data from several provinces and attempted to use this to arrive at a general picture of English in China. However, given the large and diverse population and the linguistic diversity of China, focusing on several provinces may not present an accurate composite picture of Chinese English. To date, there has been only one published study of the pronunciation of Yunnan English, from an impressionistic, auditory perspective.

The present study fills this gap by providing an acoustic investigation of segmentals and rhythm of Yunnan English and seeks to fulfill three objectives. First, it contributes to the literature on and understanding of English in China by investigating the pronunciation of learners of English from one particular province, i.e. Yunnan province. Second, it aims to investigate acoustically three aspects of pronunciation of Yunnan English, namely consonants, vowels and rhythm. Third, it attempts to establish acoustically whether Yunnan English is more similar to British English (BrE) or American English (AmE) in terms of the three aspects of pronunciation investigated. To achieve the second and third aims, comparisons are made between Yunnan English as spoken by two groups, Han and Yi speakers, BrE and AmE.

Chapters 1 to 3 introduce the background to the study, review relevant literature and describe the methodology used in the study. Chapters 4 to 6 present the analyses of and findings on Yunnan English consonants, vowels and rhythm respectively. Chapter 7 provides the summary, discussion and implications of the findings, and the conclusion.

With respect to consonants, the findings reveal that Yunnan English has some consonantal features which may be specific to Yunnan English learners. The data confirm that aspiration exists between voiceless and voiced stops in Yunnan English. And t-tapping and rhoticity are found in some instances of postvocalic /r/, suggesting there are certain AmE features in Yunnan English. The data also show that Yunnan English shares some consonantal features with speakers from other provinces reported in the previous studies.

With regard to vowels, the formant frequency measurements show the distinctive vowel qualities of Yunnan English, in comparison with those of BrE and AmE. The calculations of Euclidean distance show that the vowel space of the Yi speakers is furthest away from the centroid of the vowel quadrilateral whereas the BrE speakers have the smallest acoustic vowel space. Examination of the THOUGHT, LOT and BATH vowels, however, shows no similarity between Yunnan English and American English.

The findings for the rhythm of Yunnan English show that this Expanding Circle variety is syllable-based, as opposed to BrE and AmE which are both stress-based. Based on the findings, the study discusses some important pedagogical implications for teaching English pronunciation in Yunnan. The findings of the present study confirms that Han and Yi speakers of Yunnan English in general, share common pronunciation features and that Yunnan English may be suitably classified as an Expanding Circle learner variety of English.
229 35
Restricted
An acoustic investigation of the segmental features of educated Brunei English speech
(2010)
Salbrina Haji Sharbawi
There is a dearth of publications on the phonetics and phonology of Brunei English (BrunE). To date, there have only been four published works investigating the sounds of this English variety and out of the four, only one incorporated the use of acoustic measurements.

The present study provides an in-depth instrumental investigation of the segmental features of educated BrunE speech. Its objectives are three-fold: first, it contributes to the literature on the phonetics of BrunE; second, it aims to investigate the extent of the reliability of acoustic measurements in describing a language variety; and third, it examines the feasibility of describing an emerging English variety on its own terms without reference to an inner circle variety such as British English (BrE).

Comparison is, however, made to Singapore English (SgE). This is because it has been suggested that an English lingua franca with shared pronunciation features is developing in the Southeast Asian region. As such, comparison to SgE allows us to assess the relationship between these two English varieties, and thereby place BrunE within the context of the Southeast Asian Englishes.

After the literature review, methodology and description of data, the experimental section of this dissertation is divided into three chapters: rhoticity (Chapter Four), consonants (Chapter Five) and vowels (Chapter Six). The chapter on consonants is further divided into four sections: dental fricatives, final consonant clusters, Lvocalization and voice onset time (VOT). The chapter on vowels is divided into monophthongs and the diphthongs FACE and GOAT. The findings of the present study show that there are several similarities in the pronunciation features between BrunE and SgE. However, there are also some differences. Some of these dissimilarities are attributed to the first languages of the subjects as well as to the different stages in development of the two English varieties.

The study also finds that acoustic measurements are not always reliable in describing some pronunciation features. They prove to be reliable in investigating VOT and monophthongs but do not seem to work so well in the investigation of rhoticity, dental fricatives, final consonant clusters and L-vocalization. As for diphthongs, measurements help provide a reasonable overview of the degree of diphthongal movement but they are less valuable in describing the quality of individual tokens.

Another finding of this study is that describing an emerging English variety on its own terms is possible, though having an inner circle variety as a reference point can be beneficial particularly for values such as VOT and the degree of diphthongal movement. In an attempt to avoid prescribing to how a sound ‘should’ be pronounced, Wells’ lexical keywords are used for the vowels instead of phonetic symbols. As the lexical sets are too complex for the description of BrunE vowels, a modified approach is adopted by having a reduced number of lexical sets. However, problems are still encountered in the analysis because these keywords work on the assumption that the lexical sets are fixed, and they seem to be based entirely on the pronunciation of an inner circle variety.
228 20
Restricted
An acoustic investigation of the segmentals and suprasegmentals of Malaysian English
(2011)
Tan, Siew Kuang
Previous research on the pronunciation of Malaysian English has been scarce and those that do focus on this aspect have largely been based on auditory analysis. This present study is one of the first cross-varietal comparisons of the segmentals and suprasegmentals of Malaysian English and Singapore English using acoustic analysis to validate earlier impressionistic observations. Schneider’s Dynamic model of postcolonial English and his theory of the evolution of post-colonial Englishes forms the theoretical framework that underpins this research. Schneider has proposed that while Singapore English has moved on to Phase 4 of the Dynamic Model (endonormative stabilization), Malaysian English has fossilized and remained at Phase 3 (nativization) (2007, pp. 148, 155).

This dissertation is divided into three sections: background (Chapters 1 to 3), descriptions of two segmental and two suprasegmental aspects based on experimental phonetics (Chapters 4 to 7) and a discussion of the findings (Chapter 8).

Chapter 1 introduces Malaysian English and establishes the gap in previous research thereby motivating the research questions to be addressed in this study. Chapter 2 provides background information on English in Malaysia and Singapore as well as the theoretical framework that underpins this study. Chapter 3 deconstructs the main concepts in the title of the study as well as provides a review of some of the past work on the pronunciation of Malaysian and Singapore English.

Chapter 4 presents the duration and vowel quality measurements of the monophthongs of Malaysian English. The measurements show that for male speakers, there is a significant difference between the vowel space of the Malaysians and Singaporeans as measured by their Euclidian differences, as well as confirm that there is some conflation of vowel pairs. Findings from the work on initial voiceless and voiced stops are presented in chapter 5. The measurements show that unlike Singaporeans, Malaysians do not always differentiate between the duration of voiceless and voiced stops. In chapter 6, the rhythm of ATTENTION: The Singapore Copyright Act applies to the use of this document. Library and Information Services Centre, National Institute of Education.

Malaysian English is compared to the rhythm of Singapore English using two different indexes, the Pairwise Variability Index and VarcoV. The results in this chapter show that Malaysian English exhibits more qualities of syllable-timing than Singapore English.

Finally, chapter 6 shows that Malaysian speakers tend to use amplitude more than Singapore speakers to signal stress prominence.

In conclusion, the present study has used acoustic methods to confirm impressionistic claims about the pronunciation of Malaysian English. The discussion also demonstrates that while the features of Malaysian English confirm that it is in phase 3 of the Dynamic Model, the phase development of Singapore English is not as clear. What is obvious is that there are signs of the beginnings of a divergence in the pronunciation of the two varieties of English which may increase in the future as a result of the different language policies of the two countries in the post-independent era.
301 29
Restricted
Acute inflammatory response to exercise-induced muscle injury
(2002)
Adelbert, Daniel
The acute inflammatory response and the accompanying experiences of delayed-onset muscle soreness (DOMS) are events which occur following stress to muscle - facilitating regeneration through adaptations from injury. While theories exist to explain fatigue and the resulting micro-trauma, the exact mechanism(s) governing this process(es) is unclear. To investigate the events which underlie these phenomena, this investigation proposed the quantitative assessment of biochemical indices and immunological profiles known to directly or indirectly relate to the muscle's functional response to acute injury.

It is hypothesized that a direct/indirect relationship exists between the processes of exercise-induced muscle proteolysis and the migratory actions of neutrophils, both synergistically contributing to the active progression of the acute inflammatory response to muscle injury. This work was conducted in 3 progressive parts. Part 1 explored the immune cell and cytokine response to a single, strenuous bout of treadmill exercise to fatigue. Part 2 mapped the immune cell response and plasma-borne metabolite profile of 3 different fatiguing biceps-curl protocols that triggered DOMS. Part 3 extended the work of Part 2 to explore neutrophil-related function, enzymes and cytokines.

The fatigue-inducing treadmill running and biceps-curl exercise were employed to assess possible injury-related effects arising from whole-body and localized exercise, respectively. Statistical differences were assessed by repeated measures (RM) ANOVA; with the level of α (alpha) set at P < 0.05 and significance verified by Tukey's post-hoc analysis.

In Part 1, all WBCs counted increased (P < 0.05) from the single 20-minute bout of treadmill running to exhaustion. Although plasma IL-1β, TNF-α and IFN-γ were either undetected or unchanged with the graded running exercise to fatigue, IL-1ra, IL-6 and IL-8 profiles increased (P < 0.05) immediately following the treadmill run and returned to baseline by 6 - 24 hours post exercise. Plasma [myeloperoxidase] and [lactoferrin] were increased (P < 0.05) following the running bout and remained elevated six hours post exercise. In Part 2, increased (P < 0.05) WBC counts from localized single-arm exercise were directly correlated (r=0.83, P < 0.05) to the neutrophil. Neutrophils increased (P < 0.05) with both the eccentric and concentric groups six hours following the respective biceps-curl regimens. Post-exercise increases (P < 0.05) in plasma lactate, CK, and free protein were suggestive of muscle injury, although AST and ALT remained unchanged. DOMS was most pronounced with eccentric exercise and least with concentric exercise. In Part 3, no detectable changes were found in neutrophil adherence following single-arm exercise, although plasma myeloperoxidase and lactoferrin were elevated (P < 0.05). While plasma IL-8 increased (P < 0.05) in the eccentric and concentric exercise groups, no consistent pattern was observed with ENA-78. Finally, plasma samples from the eccentric exercise group triggered a positive chemotactic signal to purified neutrophils.

This investigation has provided a reproducible means to quantify and isolate neutrophil-specific chemoattractant(s). It demonstrates, for the first time in humans, that plasma fractions derived from a localized bout of injurious exercise does in fact contain a factor that is chemotactic to the neutrophil. Indeed, these findings could have implications for other models of acute tissue injury.
305 15
Restricted
Adaptation of Western counselling approaches to an Asian multicultural context
(1997)
Soong, Cecilia Foong Har
This study is focused on worldwide views of counselors counsellees and their use of and preference for counseling approaches.

In the light of the underlying value differences between Western and Eastern cultures, there is a need for counsellors in an Eastern culture to adapt Western approaches to the local multicultural context.

Chapter One discusses the concept of worldview, a significant antecedent factor in counseling and its correlates. The main premise is that worldviews encompassing one's 'stock of knowledge', influence one's perception of counseling and one's preference for counseling approaches.

Chapter Two is a review of the literature covering three main areas; firstly, the concept of worldviews, detailing worldview models, Asian worldviews and the Singaporean worldview. The second section elucidates mainstream counseling approaches, focusing on Client-Centered Counseling, behavioural counseling and cognitive counseling, according to their view of the person, goals of counseling, role of counsellor and techniques of counseling. The relationship between worldviews and counseling approaches is examined in the last part of the chapter, highlighting worldviews and counseling Asians - Chinese, Malays, Indians and Singaporeans.

Chapter Three describes the methodology in which a mix of quantitative and qualitative methods were employed involving two pilot studies and the main study.

Chapter Four is an analysis of the worldviews of students, with the independent variables being gender, age, ethnicity, religion, course of study, academic stream, home language and socio-economic status. The worldviews of counsellors were also analysed with the independent variables: gender, age, ethnicity, religion, education, where education was obtained, working experience, teaching subjects/majors and counseling techniques. The primary worldview for both students and counsellors was the Optimistic worldview; the Pessimistic worldview was the secondary worldview for both groups.

Chapter Five gives a description of the students' preference for counselling approaches. Students were found to prefer the cognitive and client-centered approaches to counselling, according to the quantitative data. From the qualitative interviews with the counsellors, the client-centered approach, with its emphasis on trust and relationship-building, was vouched by the counsellors to be the students' preferred counselling approach.

Chapter Six is an analysis of the counsellors' use of counselling approaches. Both quantitative and qualitative data indicated that teachers consistently used the client-centered approach primarily when working with their adolescent students, although they did employ an eclectic approach when dealing with different problems presented by their students. The social workers used both the client-centered and cognitive approaches according to the data culled from the questionnaires and the interviews. A growing trend though is their use of a family systems approach as discussed during the interviews.

Chapter Seven delineates the relationship between worldviews and counselling approaches. The primary worldview of students and counsellors was the Optimistic worldview which bespeaks the primacy of relationships, and their preferred counselling approach was the client-centered approach. However, a structured approach like cognitive counselling was also a preference among students and social workers. This augurs well with their secondary worldview, the Pessimistic worldview, where task orientation is a main characteristic.

Chapter Eight concludes with a discussion on worldviews and counseling, and their implications for counseling. In counseling students, understanding their worldviews, their preference for counseling approaches, their perceptions of teachers as counsellors, would put the counselors' work with them in good stead. Implications for counsellors embrace understanding the counsellors' own worldviews and their use of counseling approaches. These culminate in the implications for counseling training, the imperative to understand multicultural counseling and to develop multicultural competencies when counseling the culturally diverse.
778 110
Restricted
Adolescent-athlete sleep and sport performance
(2017)
Haresh T. Suppiah
Adolescents are predisposed to later sleep and wake time preferences. These intrinsically biological-driven changes to sleep behaviour are in misalignment with daily academic schedules, and are exacerbated by cultural and environmental factors, resulting in less than optimal sleep durations. This truncation in adolescent sleep is more pronounced within Asia. Furthermore, high-level adult athletes have habitually shortened sleep opportunities, and experience different sleep characteristics due to training and competition. Consequently, these student-athletes voluntarily forgo sleep in order to manage their daytime commitments. Research on the impact of chronically shortened habitual sleep on the performance of adolescent student-athletes is lacking. To address this gap, a series of five studies examined (i) sleep characteristics of adolescent student athletes and its effects on psychomotor performance, (ii) the impact of sleep extension on performance and (iii) the impact of a brief afternoon nap on cognitive and sport performance.

In Study 1, the habitual sleep characteristics of 11 male adolescent athletes (14.8 ± 0.9 years) engaged in bowling and badminton were monitored over a week, using actigraphy. A sub-sample of the participants was monitored for their sleep patterns using electroencephalography on nights following sport-specific training in the afternoon. The athletes in badminton (high intensity sport) showed significantly more deep sleep, less light sleep and wake time after sleep onset. Actigraphically-determined bedtimes and wake times were significantly delayed on weekends when mean total sleep time was also significantly longer.

Study 2 employed a similar research design as Study 1, involved 29 male adolescent athletes (14.7 ± 1.3 years) but included a psychomotor vigilance task administered on weekdays to ascertain the effects of habitual sleep durations on performance. The accrued sleep debt resulting from the shortened habitual sleep opportunities resulted in faster reaction times on Monday than on Thursday and Friday, with reaction times on Tuesday also faster than on Friday. False starts and lapsed responses also were significantly greater on Friday compared to Monday.

Study 3 compared the effects of a restricted and unrestricted sleep schedule on the shooting and cognitive performance, and measures of sleepiness and fatigue in 24 adolescent shooters (12 male; 12 female; 14.1 ± 1.4 years). Performance assessments were conducted at the start and end of a 5-day training week under both conditions. Despite no statistically significant performance changes, the data indicated moderate-to-strong associations between increases in total sleep time and certain facets of marksmanship.

Studies 4 and 5 sought to investigate the sport-specific performance effect of a brief afternoon nap on male adolescent shooters (13.8 ± 1.0 years) and track & field (14.8 ± 1.1 years) student-athletes. The nap had no measurable effect on shooting performance. However, the fastest 20m sprint times increased significantly, with mean 2m times trending towards significance amongst the track & field athletes.

In summary, this Ph.D. research showed that adolescent athletes have suboptimal sleep for training and performance, sleep debt accumulated over days exacerbated psychomotor performance and that there is the potential for performance improvement in marksmanship following moderate sleep extension. Lastly, there were varying effects of a brief afternoon nap between shooting and sprinting performance measures, warranting further research on the dose-response effects of varying nap durations on multiple sport performance measures.
272 59
Restricted
Affordance of the other : navigating the politics of teacher identity as technology kind
(2013)
Lim, Rebekah Wei Ying
The backdrop of this study on teacher identity is the lofty vision of using educational technologies to transform the nature of teaching and learning. At present, this vision has yet to be fully realized in schools. Previous attempts to unpack this disjoint between vision and reality have largely been from a system perspective such as structural barriers and unfavorable contexts. This dissertation departs from the norm by approaching the phenomenon of technology infusion from an agency perspective, underscoring the identity work involved and whether or not teachers develop to be socially regarded as being successful at technology integration, that is, as technology kind.

In particular, this dissertation investigates what teachers do and who they become as they experience technology reform on a level-wide basis in a primary school in Singapore. This work involves a teacher leader and nine other teacher participants and focuses on their sense-making during lesson design, and lesson implementation during curriculum meetings.

Based on discourse identity, four stories are presented that revealed the following: First, the positioning work that teachers performed on selves and peers as one teacher leader attempted to introduce technology to address an instructional gap. In particular, the identity work of technology kind (of the teacher leader) was temporarily lost in a curriculum meeting that was rife with various positionings. This story can be interpreted as the “baseline” of a technology-using journey for teachers.

The second and third stories describe how the constitution as technology kind slowly emerges in the social milieu. In the second story, the findings revealed two salient conditions in the constitution as technology kind. The first being the organization of that performance was found to be mediated by rhetorical devices of enactment and rationalization. When evoked, they made overt the constructivist epistemology underlying technology infusion and bore symbolic meanings of an identity as the technology kind. The second condition was the recognition of performance by a dialogic other that indexed performance in interaction as technology kind. The significance of the recognition work legitimized the technology practice and dialectically augmented the meaning of technology infusion in the social milieu.

Tied closely to the second story, the assertion in the third story is to establish the emergence of a technology practice in the social milieu. However, while there has been evidence to show that a technology practice was emerging within the group of teachers, the frequency of recurrence of identity as technology kind was low within the data collection period. This suggests that the organization of identity work has not been a straightforward process at the micro-genetic level and can be even more challenging in the longer-term aspects.

In the fourth and final story, the trajectory and growth as technology kind was examined. The study of how momentary shifts transited to a more enduring way of being was conducted using the structure and agency lens. The findings have revealed conditions of material affordance and emotion to be significant in accounting for the recurrence as technology kind.

Drawing on the four stories, I discuss what I termed as “affordance of the other” as contribution to theory and practice during technology reform. “Affordance of the other” refers to the relationship between oneself and otherness. Otherness refers to the voices of the macro circulating categorical positions, the other dialogic other in interaction and the other to one self. This construct offers a micro-interactional perspective of studying teacher identity, complementing developmental theories to account for expertise development.
403 45
Open Access
The affordances of cogenerative dialogue in mediating change within a madrasah: Power dominance, student engagement and student-teacher relationship
(2020)
Mohamed Faizal Badron
This study presents findings conducted in Madrasah Al-Ulum Islamiah (pseudonym) in Singapore with two students in the express academic stream and their physics teacher. Madrasah Al-Ulum Islamiah (MAUI) is a private non-secular school located in the Northwestern part of Singapore that offers both Islamic studies and secular subjects. MAUI is one of the six madrasahs in Singapore which is overseen by Majlis Ugama Islam Singapura (MUIS), an Islamic Religious Council of Singapore. The Islamic studies offered by the madrasah follow the standards stipulated by MUIS while the secular subjects follow the standards stipulated by the Ministry of Education (MOE).

This study examines the affordances of cogenerative (cogen) dialogue in mediating change to student engagement, student-teacher relationship and power dominance between teacher and students within a madrasah. I chose to conduct this study in a madrasah due to the difference in culture as compared to secular schools. In a madrasah, the school culture is inspired by Islamic values and belief system. I am intrigued by the affordances of cogen dialogue to mediate change in such a culture. Cogen dialogue is a relatively new field of research in Singapore and most of the studies conducted were in secular government-aided schools. There is a dearth in implementing cogen dialogue research in private madrasah such as MAUI.

Cogen dialogue is a reflective conversation between a few participants that shared a common experience in class. It provides an alternative space for participants to gather and talk about the classroom situation. The participants involved in cogen dialogue studies are mostly students, teachers and researchers. One of the desired outcomes of engaging in cogen dialogue is to catalyse change, to optimise teaching and learning praxis in the classroom. Besides optimising teaching and learning praxis, cogen dialogue plays a critical role in mediating cultures differences, managing behavioural expectations and transforming teacher identity.

Drawing from video recordings in the classroom, I wrote vignettes of interest which captured students’ gazes, gestures, spoken discourses and heart rate measurements taken during lessons. I presented those vignettes to the participants during cogen dialogue sessions and leverage on interpretation analysis to make sense of the captured gazes, gestures and spoken discourses in terms of behavioural, cognitive and emotional engagement. The students shared the challenges they faced with their teacher in an attempt to change methods of instructions in the classroom.

The analysis of change in student engagement, student-teacher relationship and power dominance mediated by cogen dialogue is grounded by the Theory of Structuration and three levels of interaction in the school – micro, meso and macro. I discussed the affordances of cogen dialogue in mediating change to the teacher’s and students’ agencies during lessons. I discussed the affordances of cogen dialogue in mediating change to the power dominance between the teacher and students after five cycles of cogen dialogue.

The significance of this study is the theoretical standpoint of cogen dialogue which differentiates it from other types of teacher-student talk. Findings from the study indicated a positive ripple effect change in the students’ engagement, student-teacher relationship and power dominance. However, the extent of the change is affected by the influence of culture. In conclusion, I highlighted six implications of the study to cogen dialogue literature and four implications to the teaching fraternity. The findings seek to provide new contributions to cogen dialogue literature.
239 129
Restricted
Aims and reasons of achievement goals : conceptualizing, measuring and applying a new goal complexes framework
(2019)
Tan, Ser Hong
Motivation lies in the crux of understanding students’ cognitions, affect, and behaviors in the academic setting. In three distinct but related studies, three key motivational constructs are examined in this dissertation: self-attributed motives, achievement goals, and goal complexes. Study 1 focuses on motives which operate by energizing behaviors towards anticipatory goal objects (McClelland, 1987). The conceptualization of self-attributed motives is underdeveloped in the literature. Thus, Study 1 seeks to conceptualize and operationalize six self-attributed motives, namely hope of success, fear of failure, hope of affiliation, fear of rejection, hope of power, and fear of loss of power. A total of 255 undergraduate students from the Philippines and 220 undergraduate students from Singapore participated in this study to develop and validate a new measure named the Self-Attributed Motive Scale (SAMS). Results showed that the SAMS displayed structural validity and measurement invariance across the two samples. Between-construct validity of the SAMS was established from the relationships between each self-attributed motive and its related outcomes.

Study 2 is centered around achievement goals. While motives energize behaviors, achievement goals are posited to direct competence-based thoughts, affect, and behaviors (Elliot, 2006). The 3 × 2 Achievement Goal Questionnaire (AGQ; Elliot, Murayama, & Pekrun, 2011) represents a recent development in the literature by focusing the definition of achievement goals on standards of competence. As otherapproach goals from the 3 × 2 AGQ were used to develop goal complex items in Study 3, Study 2 seeks to validate the 3 × 2 AGQ. A total of 320 undergraduate students from the Philippines and 243 undergraduate students from Singapore participated in this study. Structural validity and measurement invariance of the 3 × 2 AGQ were established across the two samples. Furthermore, relationships between the achievement goals in the 3 × 2 AGQ and their antecedents and outcomes also established between construct validity of the measure.

Study 3 builds on Studies 1 and 2 by examining goal complexes. Herein, a goal complex is conceptualized as an integrated construct that unifies the aim of competence strivings, as represented in achievement goals defined as standards, with its underlying reasons (Elliot, 2006). Specifically, Study 3 operationalizes a goal complex in the form of a one-to-one pairing between one other-approach goal item from the 3 × 2 AGQ with items from the SAMS, as validated in Study 1, one at a time. Thus, Study 3 seeks to develop a measure of the resultant goal complexes – hope of success/other-approach, fear of failure/other-approach, hope of affiliation/other-approach, fear of rejection/otherapproach, hope of power/other-approach, and fear of loss of power/other-approach – and examine their relationships with outcomes. A total of 370 undergraduate students from the Philippines and 235 undergraduate students from Singapore participated in this study. Structural validity and measurement invariance were established for the new measure, the Goal Complex Scale (GCS), across the two samples. The goal complexes were also found to have differential relationships with the outcomes examined. Taken together, the conceptual, methodological, and applied contributions that arise from Studies 1, 2, and 3 are discussed.
225 56
Open Access
An acoustic study of segmentals and suprasegmentals of English in Beijing, Shanghai and Guangzhou
(2023)
Yang, Rong
English in China has attracted much research and scholarship in the past few decades, but there is a general paucity of acoustic-phonetic descriptions of English in China. The present study adopts a region-based acoustic approach to thoroughly investigate phonetic features of English spoken by university students from Beijing, Shanghai, and Guangzhou, which are arguably the most economically progressive cities in China. Specifically, it aims to describe segmental (vowels and consonants) and suprasegmental (rhythm) features of Beijing English, Shanghai English, and Guangzhou English, and conduct a cross-variety comparison among the three varieties. In addition, the study seeks to determine how sociolinguistic factors such as linguistic background, academic level, and disciplinary major affect the English pronunciation of speakers from Beijing, Shanghai, and Guangzhou.
This study enlisted the participation of 45 female university students from Beijing, Shanghai, and Guangzhou with varying academic levels and disciplinary majors. They were recorded while reading short passages and sentence sets from the test materials. Their speech data was primarily analysed acoustically, with perceptual analysis to complement the acoustic analysis.
Overall, the findings indicate that Beijing English, Shanghai English, and Guangzhou English had both shared features and distinct characteristics. There was a significant difference in the first formant (F1) values of vowels between Beijing English and Guangzhou English; however, no significant differences were found in the second formant (F2) values between the three varieties. There were also significant differences in vowel duration between Beijing English and Shanghai English, and between Shanghai English and Guangzhou English. Speakers from all three cities did not distinguishing certain vowel contrasts to varying degrees. Regarding consonants, aspiration was maintained between voiceless and phonologically voiced stops for speakers from all three cities. Shanghai English had perceptually more rhotic words than Beijing English and Guangzhou English, showing significant differences in F3 values and significant differences in the distances between F2 and F3. In terms of consonantal features, speakers from all three varieties exhibited vowel epenthesis, the substitution of /θ/ and /ð/, and various vocalisations of dark /l/. Rhythmically, the nPVI values were not significantly different between the three varieties.
The linguistic background of the speakers had the most impact on all three varieties of English. Vowel quality and duration were more influenced by sociolinguistic factors, while rhythmic patterning was the least affected.
The findings of this study have helped to advance the understanding of the pronunciation features and the development of English in China, thereby contributing to the linguistic feature pool of Chinese English (CE) as a whole and the positioning of CE in the World Englishes framework.
86 236
Restricted
Analisis wacana kritis bilik darjah : interaksi dalam pengajaran dan pembelajaran Bahasa Melayu di sekolah menengah = (Classroom Critical discourse analysis: interactions in the teaching and learning of Malay language at secondary school)
(2013)
Suryani Atan
Tesis ini mengkaji wacana bilik darjah secara kritis terhadap pengajaran dan pembelajaran Bahasa Melayu di empat buah sekolah menengah di Singapura. Tesis ini bertujuan untuk melakukan deskripsi terhadap interaksi yang berlaku di dalam bilik darjah menerusi penganalisisan terhadap (i) penggunaan bahasa sebagai medium utama penyampaian pengajaran; dan (ii) hubungan kuasa serta pengaruh ideologi guru dalam pengajaran. Dengan itu, terdapat beberapa persoalan pokok yang menjadi teras kepada kajian ini, iaitu (i) apakah struktur interaksi yang diamalkan oleh guru-guru dalam data kajian semasa mengajarkan Bahasa Melayu; (ii) apakah bentuk kuasa dan ideologi yang diamalkan oleh guru-guru dalam interaksi pengajaran mereka yang mempengaruhi pengajaran dan pembelajaran Bahasa Melayu; dan (iii) bagaimanakah faktor kuasa itu boleh digunakan secara produktif oleh guru bagi meningkatkan pelibatan dan pembelajaran pelajar di dalam bilik darjah.

Tesis ini menggunakan Linguistik Fungsional Sistemik sebagai tulang belakang bagi Analisis Wacana Kritis dengan tujuan untuk melihat hubungan antara bahasa yang digunakan oleh guru-guru dalam kajian ini dengan kuasa dan ideologi serta amalan sosial. Unsur-unsur yang diambil kira ialah bidang, tenor dan mod, dengan tumpuan terhadap pemilihan leksikal atau perkataan, panggilan, modaliti, kongruensi antara jenis modus dengan fungsi bahasa, pelakuan berbahasa, giliran bertutur, serta tema tautan penghubung ayat dan panggilan, khususnya kata gantinama orang kedua. Kesemua unsur ini dilihat hubungannya dengan konteks, kuasa dan ideologi, serta amalan sosial. Menerusi bahasa yang digunakan dalam interaksi bilik darjah, kajian ini meneliti amalan kuasa dan pergelutan kuasa yang berlaku antara guru dengan pelajar sebagai partisipan dalam struktur sosial bilik darjah. Selain itu, kajian ini juga meneliti penggunaan kuasa yang produktif yang diamalkan oleh guru menerusi amalan memberikan kuasa dengan tujuan untuk memperkasakan dan mempertingkatkan pelibatan pelajar dalam pembelajaran. Ini termasuklah membincangkan peluang-peluang pembelajaran yang boleh dipertingkatkan menerusi amalan memberikan kuasa kepada pelajar.
762 327
Restricted
Analyses of purine bases by capillary electrophoresis
(2006)
Ge, Liya
This dissertation mainly deals with the analyses of purine bases by capillary electrophoresis (CE). Purine bases represent an important class of plant hormones that are implicated in various stages of plant morphology development. In addition, purine bases as well as their derivatives have been reported to have anti-cancer and anti-ageing properties. Traditionally, purine bases have been widely analyzed by the HPLC technique, and very little literature is available on the application of CE for such investigation. Therefore, this dissertation provided some substantial evidence for scientists to consider using CE as an emerging alternative method for purine bases analyses. The various optimum CE and CE-MS/MS methods developed in this dissertation were used to screen for the endogenous purine bases in coconut (Cocos nucifera L.) water. Coconut water (CW) was selected as the research material for the project due to its extensive applications in plant tissue culture and the current rather limited knowledge about the endogenous purine bases present in CW. The identities of purine bases in CW would shed important insights into the role(s) of CW in the tissue culture industry as well as the roles played by CW as health promoting beverages.

The dissertation can broadly be divided into three sections. The first section provided the relevant literature reviews of CE and purine bases (Chapters 1~3); while the second section presented the results of the various novel CE and CE-MS/MS methods developed (Chapters 4~8). In the second section, the CE and CE-MS/MS methods were successfully applied to screen for endogenous purine bases in CW, and the identities of endogenous purine bases were further confirmed by orthogonal and complementary techniques, namely HPLC or LC-MS techniques. Furthermore, the final section, i.e. Chapter 9, was devoted to giving the general conclusions and the discussion of the extension for future work.

The first section provided the historical developments and compilation of articles/key reviews published using CE over the last two decades. Next, the various theoretical aspects of CE were discussed, i.e. electroosmotic flow (EOF), electrophoretic mobility, and the influences of electrophoretic parameters on the separation. The various chemical characteristics, chemical synthetic pathways of key purine bases and nomenclature of purine bases were introduced. A brief overview of the various methods for cytokinins (6-substituted amino purines) analyses was presented, as it would be relevant to researchers who are seriously considering using CE as an emerging technique for analyzing purine bases.

The experimental results in the second section (Chapters 4~8) involved the works done by both CE and CE-MS. The CE-MS work in the dissertation is the first reported work for purine bases and their nucleotides analyses. Typically, following a solid-phase extraction (SPE) of cytokinins in CW using C18 columns, the samples were further purified by Oasis MCX columns and subsequently analyzed using the various optimized CE methods. This purification method was not suitable for analyzing the more polar cytokinin nucleotides, thus a novel dual-step SPE approach was developed at a later stage of the project.

In the first developed MEKC method, seven cytokinins were separated under a mixture of 10 mM phosphate and 10 mM borate buffer (pH 10.4) with 50 mM sodium dodecyl sulphate (SDS) in ca. 15 minutes and the method was applied to screen for two putative cytokinins (trans-zeatin-O-glucoside [ZOG], dihydrozeatin-O-glucoside [DZOG]) in CW. Subsequently, another MEKC method (optimum buffer composition: 20 mM boric acid and 50 mM SDS, pH 8.0 with an extra 20% (v/v) methanol added) was developed for the separation of six positional isomers of hydroxylated aromatic cytokinins, i.e. topolins and their ribosides. The significance of this work is that the functional role of these aromatic cytokinins is dependent on the position of their functional groups on the aromatic ring. The optimum method was successfully used for the screening of ortho-topolin (oT) in CW extract. Kinetin (free base and riboside), previously considered to be a synthetic cytokinin plant growth hormone, was detected naturally in CW using both CE and LC-MS/MS methods.

For the CE-MS/MS part, two different methods were developed for the two target groups of compounds, i.e. cytokinins (12 standards) and cytokinin nucleotides (6 standards). For both methods, the effects of various parameters i.e. pH, concentration of buffer and organic modifier, applied voltage and sheath liquid were evaluated systematically. The optimized CE-MS and CE-MS/MS methods were simple, rapid, low cost, robust, highly selective, and were successfully applied to screen for endogenous cytokinins (bases, ribosides, O-glucosides and nucleotides) in the purified CW extract sample. Due to the inherent lower sensitivity of CE method, SPE and on-line sample stacking were employed to improve on the sensitivity of cytokinin analyses. The first CE-MS/MS method was successfully applied to screen for 9 cytokinins in CW extract, including both isoprenoid and aromatic types, using a simple protocol with a volatile buffer. The second CE-MS/MS method could screen for the presence of trans-zeatin riboside-5'-monophosphate (ZMP) in CW extract. This simple direct analysis for cytokinin nucleotides is of significance, as the earlier analytical approaches involve more steps such as the tedious dephosphorylation or derivatization processes.

The final section presented the general conclusions for the successful applications of CE and CE-MS for the screening of purine bases in CW. More work should be carried out to screen for the other hormonal compounds, including novel cytokinins, auxins and gibberellins in CW.
142 9
Restricted
An analysis of feedback practices in a high-stakes exam-oriented context
(2018)
P. Ananthi
Feedback plays a crucial role in learning, motivation, and achievement (Hattie, 2009; Narciss & Huth, 2004) but surprisingly, few studies have systematically explored its meaning taking into consideration the socio-cultural contexts in which it occurs (Goldstein, 2006; Shute, 2008). Using Hattie and Timperley’s (2007) model of feedback as a framework, this study examined teacher enactment of feedback as well as student reactions to feedback to understand what teachers and students consider to be relevant and effective feedback in high-stakes exam-oriented contexts. In particular, the study focused on the factors that might have influenced feedback options and student reactions to naturally occurring written and oral feedback.

Embracing a constructivist paradigm, the study adopted a multiple case-study design (Yin, 2003) to examine the practice of feedback in two secondary schools in Singapore. Data was mainly gathered through lesson observations of four upper secondary social studies teachers, two in each school, and semi-structured interviews with these teachers and 16 Express (high-ability) students and 14 Normal (Academic) (lowability) students from the eight classrooms observed. Document analysis further complemented data gathered.

Data analysis indicated that despite variations in terms of teachers’ background, there were few differences among the four teachers in terms of feedback delivery and content. They also gave similar feedback to their Express and Normal (Academic) students regardless of the variations among the students in terms of ability. Their feedback practices were teacher-centred, which left control of the feedback process in their hands. The content of feedback was focused predominantly at task level as such feedback was considered relevant and effective to promote student performance in the subject. Express and Normal (Academic) students’ responses to feedback were comparable. They were generally supportive of their teachers’ feedback practices which they believed were beneficial for their success in the high-stakes examinations.

The socio-cultural context acted as the overarching influence on feedback. Three other mediating influences−(a) goal orientation, (b) notions of power, and (c) student emotions−also had an impact on feedback enactment and student response to feedback in a high-stakes exam-oriented context. The study highlights the implications that current feedback practices have for the learning of social studies as well as puts forth recommendations to promote feedback practices that support student capacities for self-regulation and life-long learning.
519 139
Restricted
Analysis of patterns of past tense errors in a corpus of Singapore students’ narrative writing : insights on language acquisition
(2017)
Quek, Sharon Yee Ser
This study investigates the acquisition of past tense by English learners in Singapore from the perspectives of lexical aspect and discourse grounding. Learners’ acquisition of past tense is examined at two levels: firstly, by investigating the interactions between lexical aspect (the inherent meaning of verbs) and grammatical aspect (expressed in past tense forms by morphological markers) in past tense acquisition. In other words, the study examines how learners pay attention to the inherent meanings of verbs when they learn to mark verbs morphologically in the past tense (Li and Shirai, 2000). Secondly, the interactions of the aspectual meanings of the verbs and discourse grounding have been investigated. The study examines how learners use emerging verbal morphology to distinguish between foreground (i.e. the part of the text that moves the narrative through time) and background (i.e. descriptive material that does not advance the plot) of a narrative (Bardovi-Harlig, 2002).

Two theories, namely Aspect Hypothesis (AH) and Discourse Hypothesis (DH), are tested to examine if semantic meanings of the verbs and discourse grounding can explain the acquisition of past tense markings in narrative writing. AH predicts that at the lower levels of language proficiency, learners’ past tense markings are initially restricted to telic verbs before atelic verbs. DH predicts that telic verbs will be marked more accurately in the foreground than background of narratives by learners. This study is one of the few studies in Singapore that attempt to bring the two hypotheses together to explain the acquisition of past tense.

Using a corpus-based approach, the past tense markings of 589 students from four grade levels (i.e. Primary 3, Primary 5, Secondary 1 and Secondary 3) were analysed using the UAM Corpus Tool. The findings of the study partially supported the predictions of the Aspect Hypothesis (AH). Unlike prototypical association with past tense markings (as predicted in AH), past tense markings with telic verbs were observed to be strengthened when learners’ language proficiency increased in this study. However, distributional patterns of tense-aspect past morphology by the English learners in this study showed more influence by discourse grounding where telic verbs were marked more accurately in the foreground than background of the narratives. Telicity stands out as the prominent aspectual meaning and interacts with both lexical aspect and the discourse grounding to attract more accurate past tense markings on telic verbs and in the foreground of the learners’ narratives. As a whole, the findings within this study emphasize the interactive influence of both aspectual meanings of the verb and discourse grounding as important linguistic factors to account for past tense acquisition of English learners in Singapore.
254 66
Restricted
An analysis of Singapore's wind band music education system : the challenges facing Singapore wind band instructors - beyond performance
(2004)
Lee, Tian Tee
This dissertation has two key objectives. The first is to develop a ground-level analysis of the current state of wind band music education in Singapore, and to build an understanding of the specific challenges facing local band instructors. The second is to develop a set of formative recommendations and guidelines based on the data collected in order to assist band instructors and to serve as a foundation and guide for future governmental policy-making aimed at providing students with a music education that contributes to the overall development of an appreciation for the arts and music.

Chapter One begins with a brief history of wind band development, both in general and specifically the movement in Singapore. Two complementary philosophies of band music education are presented in Chapter Two - the utilitarian and the aesthetic, and they form the framework and guiding principles for the analysis and recommendations to be developed.

Chapter Three presents the results and analysis of a comprehensive survey that was carried out over a period of three years to collect data from students, band instructors, and teachers-in-charge of bands. Based on the data collected, it is evident that there are several issues in the current band music education system that need to be addressed. The most prominent issues are a lack of band instructors with the appropriate qualifications and a national curriculum guideline for wind band education, both of which are traceable to the relatively low importance accorded to aesthetic music education.

Based on the survey analysis, Chapter Four makes recommendations on steps that can be taken to improve the situation and suggested guidelines and teaching material are presented to aid band instructors in their teaching.

Finally, the expanded role of band instructors as music educators and the challenges facing Singapore's wind band music education in the 21st century are discussed in Chapter Five. Suggestions are made to allow the wind band music education system to evolve to the next level of producing students who have a life-long appreciation for the aesthetic value of the arts and who will remain firm supporters of the arts long after they leave the education system.
760 118
Restricted
Anode geometry and focus characteristics
(1995)
Serban, Adrian
An analysis of data for plasma focus devices in their wide range of sizes has been made. The data show that for neutron optimized operation all plasma focus devices have the same peak axial sheath velocity of 10 cm/ps or a little less, driven by a standard value of characteristic current per unit anode radius I,/a of 250 kA/cm.

Dur experimental efforts were devoted to study the evolution, dynamics and focussing characteristics of a 3kJ plasma focus device operated at speeds significantly higher than 10 cm/ps. The increase in speed was achieved by increasing the linear current density using a two stage stepped-down composite anode geometry. This method of increasing the speed allows us to keep the voltage and pressure constant. The composite anode also allows us to vary the length of the speed-enhanced region. Our purpose was to investigate the possibility of enhancing the radiation output, i.e. neutrons and X-rays, for a given Input energy.

Several diagnostic techniques were applied simultaneously including the current derivative, current and voltage. The peak axial speed was measured with an optical fibre detector developed during this project. The radial and pinch phases were investigated using the shadow method. Time-resolved neutron and hard X-ray measurements were carried out using plastic scintiliator/photomultiplier systems and the time-offlight method of analysis. A neutron activation technique was used to measure the total neutron yield. Time-resolved soft X-ray measurements were performed with filtered PIN diodes. The electron temperature of the argon and deuterium focus was determined using a filter ratio method. A one-dimensional three-phase computational model was used to describe the gross dynamics of the plasma focus and to design new electrode geometries. Current shedding and mass loss effects were considered. Discharge parameters and radiation outputs were correlated. Experimental data and results of the computation were compared.

Peak axial sheath velocities up to 15 cm/ps were achieved. The composite anode configuration was optimized at 11.2 cm/p for the neutron output, for which an increase of 70% compared to the standard electrode geometry was achieved. At the same time, the soft X-ray outpu~ increased by almost four times. The results showed that if the speed enhanced section was too long the radial compression was not driven properly resulting in poor reproducibility, efficiency and radiation output. This could be ascribed to a significant separation of the plasma layer from the magnetic piston at the end of the axlal phase.

Shadowgraphic investigations showed that as the speed increased the sheath was more canted. This aspect was correlated with the mass loss effect and was taken into account in the computational model.

Two focus evolution regimes were identified. One is a single compression during the pinch phase and leads to high neutron yield. The other regime features multiple compressions of the plasma with high soft X-ray production. Focussing characteristics depend strongly on gas filling pressure and speed. The optimum conditions for neutron yield are different from those for soft X-ray production. The peak value of plasma impedance (typically greater than 0.2 Q) during focusing was proposed as a factor of merit. Electron temperatures of 1 - 2 kev were determined for both the argon and deuterium focus.

Each linear dimension of the pinch and the lifetime of the focus phase were found to scale proportionally to the anode radius. Scaling laws for the non-beam component of the neutron yield and soft X-ray production were proposed based on the experimental results. These show a strong enhancement of the neutron and soft X-ray yields when the focus axial speed is increased.
393 19