Development of an optical flow through detector for bubbles, crystals and particles in oils

Oscillating microbubbles, driven by the local sound field, and crystals are detected and sized in oils as they pass through an optical detector.

Developing the New Zealand Soundmap: An exploration of soundmap practice, site listening, locative media and the sound environment

<p>This text is an exegesis written in accompaniment to the development of the New Zealand Soundmap. The origin and development of soundmap practice and the emergence and development of related environmental sound practices are detailed. The exegesis concludes with an exposition of the development of the New Zealand Soundmap itself. Soundmap practice emerged from the sonic explorations of the World Soundscape Project, who coming out of Simon Fraser University of Burnaby, British Columbia, Canada, pioneered the first soundmaps in the early 1970’s. From its origins soundmap practice has spread and developed into its current form as a new media practice. This thesis deals with the development of a regional web-based soundmap for New Zealand. Various discursive strains from media studies, sonic arts, and phenomenological philosophy are woven together to explain the impetus, and value of soundmap practice and related environmental sound practices such as soundwalks and site-listening. The thesis ends with a critical analysis of successes and failures of the project towards its stated goal: to facilitate awareness of an engagement with the local sound environment.</p>

Developing the New Zealand Soundmap: An exploration of soundmap practice, site listening, locative media and the sound environment

<p>This text is an exegesis written in accompaniment to the development of the New Zealand Soundmap. The origin and development of soundmap practice and the emergence and development of related environmental sound practices are detailed. The exegesis concludes with an exposition of the development of the New Zealand Soundmap itself. Soundmap practice emerged from the sonic explorations of the World Soundscape Project, who coming out of Simon Fraser University of Burnaby, British Columbia, Canada, pioneered the first soundmaps in the early 1970’s. From its origins soundmap practice has spread and developed into its current form as a new media practice. This thesis deals with the development of a regional web-based soundmap for New Zealand. Various discursive strains from media studies, sonic arts, and phenomenological philosophy are woven together to explain the impetus, and value of soundmap practice and related environmental sound practices such as soundwalks and site-listening. The thesis ends with a critical analysis of successes and failures of the project towards its stated goal: to facilitate awareness of an engagement with the local sound environment.</p>

Sound evaluation of urban spaces in the central area of São Paulo

The present work evaluates noise conditions to which people are subject in the central region of São Paulo city. Strategic points were chosen for sound assessment, considering quantitative and qualitative aspects. Different occupancy profiles, height of buildings, constructive density, number of empty spaces, width of the roads and capacity of vehicle flow, were selected. In addition to acoustic measurements, an evaluation of the profile and flow of the vehicles has been made, to serve as input for simulation in a computational model of urban environmental noise and noise mapping of selected areas. The concept of soundscape was approached with the characterization of local sound sources and their sound perception. Questionnaires were applied for subjective assessment and the profile of the interviewees was also characterized. This attitude is important because it leads to an understanding of who exactly is exposed and affected by certain sound levels, and how the same sound level can generate different perceptions. This sensibility while approaching the subject makes people stop being just numbers and more human strategies are adopted for urban planning. At the end, an image was produced to summarize the overall analysis performed.

Fluctuation and extinction of laminar diffusion flame induced by external acoustic wave and source

Acoustic wave can destabilize the flame and has a potential in firefighting, but the influences of the sound source and its frequency are still poorly understood. This work applies a loudspeaker to extinguish a laminar diffusion propane flame of 5–25 mm high, where the local sound frequency is 50–70 Hz and sound pressure is 0.8–3.2 Pa (92.0–104.1 dB). Results reveal a constant flame pulsating displacement at the extinction limit, independent of the sound environment used. Such a flame pulsating displacement is found to be caused by the motion of the speaker membrane (or diaphragm) and its induced wind, which could be two orders of magnitude larger than the displacement of the air that transmits acoustic wave. Thus, under the influence of sound source, a critical flame strain rate, stretched by the pulsating airflow, can be formulated to characterize the blow-off limit better than the local sound pressure. The sound source with a lower frequency can produce larger pulsating displacements of both membrane and flame, and thus promoting extinction. This work improves the understanding of flame dynamics under the external sound field and source, and it helps establish a scientific framework for acoustic-based fire suppression technologies.

(Divergent) Participation in the California Vowel Shift by Korean Americans in Southern California

This study investigates the participation in the California Vowel Shift by Korean Americans in Los Angeles. Five groups of subjects participated in a picture narrative task: first-, 1.5-, and second-generation Korean Americans, Anglo-Californians, and (non-immigrant) Korean late learners of English. Results showed a clear distinction between early vs. late bilinguals; while the first-generation Korean Americans and the late learners showed apparent signs of Korean influence, the 1.5- and the second-generation Korean Americans participated in most patterns of the California Vowel Shift. However, divergence from the Anglo-Californians was observed in early bilinguals’ speech. Similar to the late bilinguals, the 1.5-generation speakers did not systematically distinguish prenasal and non-prenasal /æ/. The second-generation speakers demonstrated a split-/æ/ system, but it was less pronounced than for the Anglo-Californians. These findings suggest that age of arrival has a strong effect on immigrant minority speakers’ participation in local sound change. In the case of the second-generation Korean Americans, certain patterns of the California Vowel Shift were even more pronounced than for the Anglo-Californians (i.e., /ɪ/-lowering, /ɑ/-/ɔ/ merger, /ʊ/- and /ʌ/-fronting). Moreover, the entire vowel space of the second-generation Korean Americans, especially female speakers, was more fronted than that of the Anglo-Californians. These findings suggest that second-generation Korean Americans may be in a more advanced stage of the California Vowel Shift than Anglo-Californians or the California Vowel Shift is on a different trajectory for these speakers. Possible explanations in relation to second-generation Korean Americans’ intersecting gender, ethnic, and racial identities, and suggestions for future research are discussed.