The purposes of the study are as follows: 1. To delineate the functions of the different component parts of a loudspeaker so as to show its working relationship with the enclosure or baffle 2. To analyze the basic types of speaker enclosure designs and to define their application for use in woodworking shop projects. 3. To explore the skills and knowledge needed to build correctly a highly functional speaker system cabinet. 4. To present these construction techniques in such a way as they might be helpful to the prospective builder of a speaker system enclosure. 5. To provide a helpful guide for the design and construction of hi-fidelity cabinetry and to help the builder avoid needless and costly mistakes of acoustic and aesthetic design.

In foreign language education the classification native or nonnative speaker of a language often evokes thoughts related to degrees of competence in language teaching (Braine, 2004; Davies, 2004). This comparative case study focused on Spanish teachers in a United States context. It contributes toward the literature base in research related to native and nonnative speakers of languages other than English within the local context. Using the threefold theoretical framework of role identity theory (Stryker, 1968; Stryker & Burke, 2000), teacher efficacy (Tschennen Moran & Woolfolk Hoy, 2001) and social constructivism (Schwandt, 2007), the study aimed at developing understandings about the lived experience of foreign language teachers given the native/ nonnative speaker construct. It investigated how their personal perception of their role impacted the execution of professional duties. It also explored their conceptualization of the language teacher, given their extensive observation of teachers of various languages. The questions guiding the research were: (a) How does each participant conceptualize her role identity as Spanish teacher in a predominantly English speaking setting?, (b) How viable is the native/nonnative speaker construct when teacher efficacy is considered?, and (c) how has the experience of supervising teachers of differing linguistic backgrounds in the language they teach (native/nonnative speaker teachers) influenced the participants’ understanding of the language teacher construct in the USA? Data collection was done through interviews, focus group discussions and classroom observations. The participants were four veteran Spanish teachers who had been in the department chair position for more than ten years. Two grew up speaking the language while the others learned the language in an academic setting. Findings revealed that there was great similarity in the way teachers conceptualized their role as Spanish teacher and that they gave no credence to the native/ nonnative speaker construct as an indicator of language proficiency and competence in language teaching.

Through the implementation of a closed and open-item questionnaire, parents’ (N=40) perceptions of and attitudes toward native and non-native French-speaking teachers (NFSTs and Non-NFSTs) of French as a Second Language in the Greater Toronto Area were investigated. Participants defined the native French speaker predominantly as someone who learned French as a first language and who learned French in informal environments – namely home and community. Descriptive statistics of 24 Likert-scale items revealed preference for NFSTs to teach oral-aural aspects, the written system of French and form better student relationships. Non-NFSTs were preferred to teach reading, vocabulary, learning strategies and make connections between English and French more salient. Parents stated a variety of strengths and areas needing improvement for both NFSTs and Non-NFSTs, which suggested complimentary and complementary views of these teachers.

Through the implementation of a closed and open-item questionnaire, parents’ (N=40) perceptions of and attitudes toward native and non-native French-speaking teachers (NFSTs and Non-NFSTs) of French as a Second Language in the Greater Toronto Area were investigated. Participants defined the native French speaker predominantly as someone who learned French as a first language and who learned French in informal environments – namely home and community. Descriptive statistics of 24 Likert-scale items revealed preference for NFSTs to teach oral-aural aspects, the written system of French and form better student relationships. Non-NFSTs were preferred to teach reading, vocabulary, learning strategies and make connections between English and French more salient. Parents stated a variety of strengths and areas needing improvement for both NFSTs and Non-NFSTs, which suggested complimentary and complementary views of these teachers.

Techn. University, Diss., 2004--Chemnitz.

No description available.

No description available.

This study explores the ways that native speakers are represented in different discourses. It combines the personal with the empirical by starting with narratives of professional development, followed by a corpus analysis of how native speakers are defined, and ending with a critical discourse analysis of the roles allocated to native speakers in academic discourse. First, the use of narrative inquiry speaks to the lived experience of three native English speaking language teachers as they develop their professional identity and seek professional development. Their narratives uncover the tensions between their personal goals and external perceptions. In order to situate these narratives in the field, a corpus analysis identifies the difference between how native speakers are defined in general discourse and within academic literature. These different definitions demonstrate distinct patterns of usage that differentiate the concept of the native speaker, the native speaker of English, and the native speaker of English as a language teacher. Finally, a critical discourse analysis illuminates the dominant representations of native speakers in academic literature. An interpretation of six academic articles, drawing on van Leeuwens network of role allocation, highlights: 1) how native speakers are differentiated from non-native speakers; 2) how native speaking language teachers are objectified or excluded from the discourse. The analysis reveals how representations of native speakers influence the participation of native English speaking language teachers in the field of TESOL. The implications indicate that the current representations of native speakers detract from professional development by perpetuating static identities rather than encouraging professional development.

The focus of this thesis is the relationship between the articulation ofspeech and the acoustics of produced speech. There are several problems thatare encountered in understanding this relationship, given the non-linearity,variance and non-uniqueness in the mapping, as well as the differences thatexist in the size and shape of the articulators, and consequently the acoustics,for different speakers. The thesis covers mainly four topics pertaining to thearticulation and acoustics of speech.The first part of the thesis deals with variations among different speakersin the articulation of phonemes. While the speakers differ physically in theshape of their articulators and vocal tracts, the study tries to extract articula-tion strategies that are common to different speakers. Using multi-way linearanalysis methods, the study extracts articulatory parameters which can beused to estimate unknown articulations of phonemes made by one speaker;knowing other articulations made by the same speaker and those unknown ar-ticulations made by other speakers of the language. At the same time, a novelmethod to select the number of articulatory model parameters, as well as thearticulations that are representative of a speaker’s articulatory repertoire, issuggested.The second part is devoted to the study of uncertainty in the acoustic-to-articulatory mapping, specifically non-uniqueness in the mapping. Severalstudies in the past have shown that human beings are capable of producing agiven phoneme using non-unique articulatory configurations, when the artic-ulators are constrained. This was also demonstrated by synthesizing soundsusing theoretical articulatory models. The studies in this part of the the-sis investigate the existence of non-uniqueness in unconstrained read speech.This is carried out using a database of acoustic signals recorded synchronouslyalong with the positions of electromagnetic coils placed on selected points onthe lips, jaws, tongue and velum. This part, thus, largely devotes itself todescribing techniques that can be used to study non-uniqueness in the sta-tistical sense, using such a database. The results indicate that the acousticvectors corresponding to some frames in all the phonemes in the databasecan be mapped onto non-unique articulatory distributions. The predictabil-ity of these non-unique frames is investigated, along with verifying whetherapplying continuity constraints can resolve this non-uniqueness.The third part proposes several novel methods of looking at acoustic-articulatory relationships in the context of acoustic-to-articulatory inversion.The proposed methods include explicit modeling of non-uniqueness usingcross-modal Gaussian mixture modeling, as well as modeling the mappingas local regressions. Another innovative approach towards the mapping prob-lem has also been described in the form of relating articulatory and acousticgestures. Definitions and methods to obtain such gestures are presented alongwith an analysis of the gestures for different phoneme types. The relationshipbetween the acoustic and articulatory gestures is also outlined. A method toconduct acoustic-to-articulatory inverse mapping is also suggested, along withva method to evaluate it. An application of acoustic-to-articulatory inversionto improve speech recognition is also described in this part of the thesis.The final part of the thesis deals with problems related to modeling infantsacquiring the ability to speak; the model utilizing an articulatory synthesizeradapted to infant vocal tract sizes. The main problem addressed is related tomodeling how infants acquire acoustic correlates that are normalized betweeninfants and adults. A second problem of how infants decipher the number ofdegrees of articulatory freedom is also partially addressed. The main contri-bution is a realistic model which shows how an infant can learn the mappingbetween the acoustics produced during the babbling phase and the acous-tics heard from the adults. The knowledge required to map correspondingadult-infant speech sounds is shown to be learnt without the total numberof categories or one-one correspondences being specified explicitly. Instead,the model learns these features indirectly based on an overall approval rating,provided by a simulation of adult perception, on the basis of the imitation ofadult utterances by the infant model.Thus, the thesis tries to cover different aspects of the relationship betweenarticulation and acoustics of speech in the context of variations for differentspeakers and ages. Although not providing complete solutions, the thesis pro-poses novel directions for approaching the problem, with pointers to solutionsin some contexts. / QC 20111222 / Computer-Animated language Teachers (CALATea), Audio-Visual Speech Inversion (ASPI)

Speaker verification is the process of verifying or disputing the claimed identity of a speaker based on a recorded sample of their speech. Automatic speaker verification technology can be applied to a variety of person authentication and identification applications including forensics, surveillance, national security measures for combating terrorism, credit card and transaction verification, automation and indexing of speakers in audio data, voice based signatures, and over-the-phone security access. The ubiquitous nature of modern telephony systems allows for the easy acquisition and delivery of speech signals for processing by an automated speaker recognition system. Traditionally, approaches to automatic speaker verification have involved holistic modelling of low-level acoustic-based features in order to characterise physiological aspects of a speaker such as the length and shape of the vocal tract. Although the use of these low-level features has proved highly successful, there are numerous other sources of speaker specific information in the speech signal that have largely been ignored. In spontaneous and conversational speech, perceptually higher levels of in- formation such as the linguistic content, pronunciation idiosyncrasies, idiolectal word usage, speaking rates and prosody, can also provide useful cues as to identify of a speaker. The main aim of this work is to explore the incorporation of higher levels of information into the verification process. Specifically, linguistic constructs such as words, syllables and phones are examined for their usefulness as features for text-independent speaker verification. Two main approaches to incorporating these linguistic features are explored. Firstly, the direct modelling of linguistic feature sequences is examined. Stochastic language models are used to model word and phonetic sequences obtained from automatically obtained transcripts. Experimentation indicates that significant speaker characterising information is indeed contained in both word and phone-level transcripts. It is shown, however, that model estimation issues arise when limited speech is available for training. This speaker model estimation problem is addressed by employing an adaptive model training strategy that significantly improves the performance and extended the usefulness of both lexical and phonetic techniques to short training length situations. An alternate approach to incorporating linguistic information is also examined. Rather than modelling the high-level features independently of acoustic information, linguistic information is instead used to constrain and aid acoustic- based speaker verification techniques. It is hypothesised that a ext-constrained" approach provides direct benefits by facilitating more detailed modelling, as well as providing useful insight into which articulatory events provide the most useful speaker-characterising information. A novel framework for text-constrained speaker verification is developed. This technique is presented as a generalised framework capable of using di®erent feature sets and modelling paradigms, and is based upon the use of a newly defined pseudo-syllabic segmentation unit. A detailed exploration of the speaker characterising power of both broad phonetic and syllabic events is performed and used to optimise the system configuration. An evaluation of the proposed text- constrained framework using cepstral features demonstrates the benefits of such an approach over holistic approaches, particularly in extended training length scenarios. Finally, a complete evaluation of the developed techniques on the NIST2005 speaker recognition evaluation database is presented. The benefit of including high-level linguistic information is demonstrated when a fusion of both high- and low-level techniques is performed.