Vowel Intelligibility of Saudi Spoken English

This thesis serves two purposes. The first is to describe Saudi-accented English vowels acoustically. The second is to rely on the measurements obtained from the acoustic phonetic analyses to assess the intelligibility of their vowels. The methodology pioneered by Peterson and Barney (1952) and replicated by Hillenbrand et al. (1995) in their studies of General American English (GAE) is adopted in this study. However, unlike the two previous studies that measured vowels in citation forms, this study measures the acoustic correlates of vowels in running speech style. The participants are 32 Saudi educators who teach English as a Foreign Language (EFL) in the Kingdom of Saudi Arabia: 23 females and 9 males. They were recorded reading a longer version of the GMU Speech Accent Archive text. The analysis focuses on the 11 monophthong phonemic vowel of English. Three different words containing each one of the 11 vowels under consideration were isolated, annotated, and measured for F0, F1, F2, F3, F4, intensity and duration. The software program used is Praat. The annotation and feature extraction were done manually to minimize errors. The first (F1) and second (F2) formants were used to create acoustic vowel spaces. Intelligibility assessments are based on Koffi’s (2019) Acoustic Masking and Intelligibility (AMI) theory. He contends that intelligibility of vowels can be measured instrumentally by comparing the F1 of vowels because this formant carries 80% of the acoustic energy found in vowels. The AMI theory also combines Just Noticeable Differences (JND) thresholds and Relative Functional Load (RFL) calculations to gauge severity of masking and intelligibility. Using this approach, the intelligibility of Saudi-accented vowels is assessed in two ways: internally and externally. Internal masking analyses focus on whether or not Saudi speakers differentiate clearly among the English vowels when they speak. External masking focuses on whether or not the vowels produced by Saudi speakers mask the vowels produced by GAE speakers. The findings discussed in this thesis are based on 7,392 measured tokens. The pedagogical implications and applications recommended in this thesis are data-driven. The most important insights that one can glean from this study is the kiss vowel [ɪ], the foot vowel [ʊ], and the trap vowel [æ] are the most problematic vowels for Saudi speakers of English. Since the RFL of [ɪ] and [æ] are particularly high, it is recommended that the pronunciation of these two vowels be prioritized in instruction

Vowel Intelligibility Analysis of Female Saudi Spoken English

This article describes the acoustic characteristics of female Saudi-accented English vowels and uses acoustic phonetic measurements to assess the intelligibility of their vowels. Peterson & Barney’s (1952) and Hillenbrand et al.’s (1995) methodology is slightly modified. Whereas their studies extracted various measurements, including F1 and F2 of vowels in General American English (GAE), the current study examines measurements extracted from 11 monophthong phonemic English vowels in running speech produced by 23 female Saudi EFL teachers. Intelligibility assessments of their vowels are based on Koffi’s (2019) Acoustic Masking and Intelligibility (AMI) theory. He contends that intelligibility of vowels can be measured instrumentally by comparing the F1 of vowels because this formant carries 80% of the acoustic energy found in vowels. The AMI theory also combines Just Noticeable Differences (JND) thresholds and Relative Functional Load (RFL) calculations to gauge severity of masking and intelligibility. The findings in this article are based on 1,518 measured tokens. The study reveals that the fleece vowel [i], the kiss vowel [ɪ] and the face vowel [e] are the most problematic for Saudi speakers of English

Tapering Enhanced Stimulated Superradiant Oscillator

In this paper, we present a new kind of high power and high efficiency free-electron laser oscillator based on the application of the tapering enhanced stimulated superradiant amplification (TESSA) scheme. The main characteristic of the TESSA scheme is a high intensity seed pulse which provides high gradient beam deceleration and efficient energy extraction. In the oscillator configuration, the TESSA undulator is driven by a high repetition rate electron beam and embedded in an optical cavity. A beam-splitter is used for outcoupling a fraction of the amplified power and recirculate the remainder as the intense seed for the next electron beam pulse. The mirrors in the oscillator cavity refocus the seed at the undulator entrance and monochromatize the radiation. In this paper we discuss the optimization of the system for a technologically relevant example at 1 $\mu$m using a 1~MHz repetition rate electron linac starting with an externally injected igniter pulse.Comment: 24 pages, 13 figure

English Proficiency Profile Study of an L2 Speaker from the Kingdom of Saudi Arabia

English is the main foreign language in schools in the Kingdom of Saudi Arabia. Even though the Kingdom has made considerable budgetary sacrifices to raise English proficiency in the country, the results do not yet match expectations. According to English First (EF), in 2019, Saudi Arabia ranked “very low” on the English Proficiency Index (EPI). We dig deeper to understand why a few succeed where most fail. In so doing, we examine the learning opportunities and practices of (KSA-F1), a female Saudi teacher of English, to understand the secrets of her success. We also study her pronunciation of English vowels to see where improvement is still needed. Aspects of the paper focus on the description of her social network and her acoustic vowel space. The analysis reveals that in spite of the strides that she has made, her vowels [ɪ] and [e] mask each other internally, while her vowels [æ] and [ɔ] mask General American English (GAE) [ɑ] and [ʊ] respectively. Given the high relative functional load of the masked the vowels, except for [ɔ] vs. [ʊ], intelligibility can be easily jeopardized if the discourse context lacks sufficient syntactic redundancies

Two Lower Bounds In Asynchronous Distributed Computation

We introduce new techniques for deriving lower bounds on the message complexity in asynchronous distributed computation. These techniques combine the choice of specific patterns of communication delays and crossing sequence arguments with consideration of the speed of propagation of messages, together with careful counting of messages in different parts of the network. They enable us to prove the following results, settling two open problems: An Ω(n log* n) lower bound for the number of messages sent by an asynchronous algorithm for computing any nonconstant function on a bidirectional ring of n anonymous processors. An Ω(n log n) lower bound for the average number of messages sent by any maximum finding algorithm on a ring of n processors, in case n is known

LET’S STRESS IT! INVESTIGATIONS OF SAUDI EFL TEACHERS’ LEXICAL STRESS PATTERNS

Koffi (2019) investigated the acoustic correlates that Arabic L2 speakers of English use to encode lexical stress. This study replicates the same methodology and uses the same acoustic correlates and the same Just Noticeable Difference (JND) thresholds. Whereas Koffi (2019) focused on a general population of Arabic speakers of English, the current study investigates how 10 females Saudi L2 speakers of English who are college professors encode lexical stress. Do they encode lexical stress similarly or differently from the group that Koffi (2019) investigated? What does this entail for the acquisition of suprasegmentals in L2 English

Syntax tree fingerprinting: a foundation for source code similarity detection

Plagiarism detection and clone refactoring in software depend on one common concern: nding similar source chunks across large repositories. However, since code duplication in software is often the result of copy-paste behaviors, only minor modi cations are expected between shared codes. On the contrary, in a plagiarism detection context, edits are more extensive and exact matching strategies show their limits. Among the three main representations used by source code similarity detection tools, namely the linear token sequences, the Abstract Syntax Tree (AST) and the Program Depen- dency Graph (PDG), we believe that the AST could e ciently support the program analysis and transformations required for the advanced similarity detection process. In this paper we present a simple and scalable architecture based on syntax tree nger- printing. Thanks to a study of several hashing strategies reducing false-positive collisions, we propose a framework that e ciently indexes AST representations in a database, that quickly detects exact (w.r.t source code abstraction) clone clusters and that easily retrieves their corresponding ASTs. Our aim is to allow further processing of neighboring exact matches in order to identify the larger approximate matches, dealing with the common modi cation patterns seen in the intra-project copy-pastes and in the plagiarism cases