Task parallelness: investigating the difficulty of two spoken narrative tasks

This thesis explores how task parallelness might be established; this is of fundamental importance to any discussion in the areas of language testing and task-based research, where the equivalence of tasks is a prerequisite. Five pilot studies were conducted using two spoken narrative tasks from an ongoing speaking test of English in Japan, the Standard Speaking Test, including two feasibility studies using several linguistic variables to analyse candidate performances, a study of expert judgements of the two tasks, a study of the linguistic performance of native speakers of English, and a study to identify an appropriate pair of tasks for the main study. The main study examined the parallelness of two spoken narrative tasks by Hill (1960) in terms of the ratings calculated by MFRM analysis, the linguistic performances of 65 Japanese candidates and 11 native speakers of English, expert judgements by Japanese teachers of English, and perceptions of the Japanese candidates and native speakers of English. The validity of the linguistic variables was also examined. The results of analyses demonstrated that the two tasks were not actually parallel, despite the effort to ensure a priori parallelness via the pilot studies. The findings were extensively discussed in relation to the theories of task complexity from Robinson (2001) and Skehan (1998), and raised several questions regarding the variables for quantifying the accuracy and syntactic complexity of linguistic performance. Taken together, the findings of this thesis add significantly to the understanding of task parallelness and the results of my work can be applied not only to the design and selection of tasks but also to the investigation of linguistic performance in the fields of language testing and task-based research

Accuracy across proficiency levels: A learner corpus approach. Jennifer Thewissen. Presses Universitaires de Louvain, Lougain-la-Neuve, Belgium (2015). 342pp.

A review of the book based on Thewissen’s PhD thesis, which used the International Corpus of Learner English (ICLE) (Granger et al., 2009) for two main purposes. The first purpose was to capture the development of linguistic accuracy of the argumentative essays written by learners of English at intermediate to advanced levels, namely B1 to C2 in the Common European Framework of Reference (CEFR) (Council of Europe, 2001). The second purpose was to create a set of L1-specific CEFR descriptors related to the linguistic accuracy by building on the results from the essays written by learners who have French as their L1.

Magnetic Field Amplification Associated with the Richtmyer-Meshkov Instability

The amplification of a magnetic field due to the Richtmyer-Meshkov instability (RMI) is investigated by two-dimensional MHD simulations. Single-mode analysis is adopted to reveal definite relation between the nonlinear evolution of RMI and the field enhancement. It is found that an ambient magnetic field is stretched by fluid motions associated with the RMI, and the strength is amplified significantly by more than two orders of magnitude. The saturation level of the field is determined by a balance between the amplified magnetic pressure and the thermal pressure after shock passage. This effective amplification can be achieved in a wide range of the conditions for the RMI such as the Mach number of an incident shock and the density ratio at a contact discontinuity. The results suggest that the RMI could be a robust mechanism of the amplification of interstellar magnetic fields and cause the origin of localized strong fields observed at the shock of supernova remnants.Comment: 16 pages, 9 figures, accepted for publication in Ap

Spreading Law of Evaporative Droplets

Droplet spreading is ubiquitous and plays a significant role in applications such as spray cooling, inkjet printing, and micro-flow devices. While the spreading of non-volatile droplets can be described by the competition between capillary and viscous dissipation, namely the Tanner's law, R(t)~t1/10, the spreading and flow transition in volatile droplets remains elusive due to the complexity added by interfacial phase change. Here we show, using both theoretical modeling and experiments, that the wetting dynamics of volatile droplets can be scaled by the spatial temporal interplay between capillary, evaporation, and thermal Marangoni effects. We quantify these complex interactions using phase diagrams based on detailed theoretical and experimental analyses. We further illustrate the spreading law of droplets by generalizing the Tanner's law to a full range of liquids with saturation vapor pressure spanning from 101 to 104 Pa and on substrates with thermal conductivity spanning from 10-1 to 103W/m/K. Our conclusions enable a unifying explanation to a series of individual works including the criterion of flow reversal and the state of dynamic wetting, making it possible to control liquid transport in diverse application scenarios

Exploring the use of video-conferencing technology in the assessment of spoken language: a mixed-methods study

This research explores how internet-based video-conferencing technology can be used to deliver and conduct a speaking test, and what similarities and differences can be discerned between the standard and computer-mediated face-to-face modes. The context of the study is a high-stakes speaking test, and the motivation for the research is the need for test providers to keep under constant review the extent to which their tests are accessible and fair to a wide constituency of test takers. The study examines test-takers’ scores and linguistic output, and examiners’ test administration and rating behaviors across the two modes. A convergent parallel mixed-methods research design was used, analyzing test-takers’ scores and language functions elicited, examiners’ written comments, feedback questionnaires and verbal reports, as well as observation notes taken by researchers. While the two delivery modes generated similar test score outcomes, some differences were observed in test-takers’ functional output and the behavior of examiners who served as both raters and interlocutors

Personality, subjective well-being, and the serotonin 1a receptor gene in common marmosets (Callithrix jacchus)

Studies of personality traits in common marmosets (Callithrix jacchus) indicate that there are five or six constructs—Sociability, Dominance, Neuroticism, Openness, and two related to Conscientiousness. The present study attempted to determine whether our earlier study of laboratory-housed individuals only yielded three—Dominance, Sociability, and Neuroticism—because of a low amount of between-subjects variance. To do so, we increased our sample size from 77 to 128. In addition, we ascertained the reliability and validity of ratings and whether polymorphisms related to the serotonin 1a receptor were associated with personality. We found Sociability, Dominance, and Negative Affect factors that resembled three domains found in previous studies, including ours. We also found an Openness and Impulsiveness factor, the latter of which bore some resemblance to Conscientiousness, and two higher-order factors, Pro-sociality and Boldness. In further analyses, we could not exclude the possibility that Pro-sociality and Boldness represented a higher-level of personality organization. Correlations between personality factors and well-being were consistent with the definitions of the factors. There were no significant associations between personality and genotype. These results suggest that common marmoset personality structure varies as a function of rearing or housing variables that have not yet been investigated systematically