bluuebunny/crossref_metadata_2025 huggingface dataset:
Language-general and language-specific influences on Dutch and Japanese infants’ perception of place of articulation
Authors: Tsuji Sho
Published: November 2019

Perceptual asymmetries provide a window into the role of language-general biases and language-specific experiences in early phonetic development. We assessed infant perception of two asymmetries related to coronal place of articulation and documented across the inventories of languages. To disentangle the role of language-general tendencies and experiential factors, we compared early perception of infants learning Dutch (where the input is consistent with language-general tendencies) and Japanese (where this is not the case). First, we document that both Dutch and Japanese infants start out with asymmetric discrimination of labial-coronal consonant contrasts consistent with language-general predictions at 4–6 months of age, but that, consistent with input-based predictions, this pattern declines in Japanese, but not Dutch toddlers by 18 months of age. Second, we show that infants from both language groups develop phonotactic preferences consistent with their input but with different timelines, with French infants developing a labial-coronal preference by 10 months, and Japanese infants a delayed coronal-labial preference by 13 months of age. Together, these results demonstrate that language-specific input characteristics start overriding language-general tendencies, but also suggest that these language-general tendencies continue playing a role in perception. We speculate about sources of these biases on the acoustic, perceptual, and articulatory level.
The Lofoten-Vesterålen Ocean Observatory—A cabled infrastructure for operational acoustical oceanography
Authors: Pedersen Geir , Johnsen Espen , Ødegaard Lars Alf , Zhang Guosong , Grimsbø Endre , Macaulay Gavin , Reinen Tor Arne , Hermansen Anders
Published: November 2019

In the face of climate change and increasing use of coastal areas, there is a need for high temporal resolution data provided in near real-time, serving research, management, and commercial users. The main objective of Lofoten-Vesterålen (LoVe) Cabled Ocean Observatory is to significantly contribute to the knowledge base of the physical, chemical, and biological environment of the ecologically and economically important LoVe shelf-slope-system. Key sensors for this task are based on acoustical methods for biological and physical oceanography. The majority of the observatory nodes are equipped with state-of-the art scientific echosounders, hydrophones, and acoustic Doppler current profilers (ADCP). Echosounders monitor vertical distribution and density of marine organisms (fish, zooplankton) and biomass flux across the observatory transect. Hydrophones provide continuous monitoring of anthropogenic noise and detection (absence/presence) of vocalizing marine mammals and fish. In addition to the fiber optic communication along the infrastructure subsea cables, each node has the capability of acoustic communication to non-cabled nodes, vessels, and vehicles. The instrument nodes and satellites on which the sensors are mounted feature a range of novel solutions, including technologies contributing to significant reduction in the cost of maintaining the infrastructure compared to traditional cabled infrastructure technologies.
Effects of room acoustics on talkers: A use case for speech-acoustic signal processing in architectural acoustics
Authors: Rollins Michael , Leishman Timothy W. , Hunter Eric J.
Published: November 2019

In the past, several room-acoustic parameters, recommendations, and standards have been developed with emphasis on accommodating the listener. Recent research has shown that talkers also respond to room acoustics via vocal adaptations. In fact, room acoustics may influence the development of voice disorders in occupational speech users. To evaluate the relationships between room acoustics and vocal parameters of healthy talkers, the authors of this presentation analyzed speech-acoustic signals under a variety of acoustical conditions. Vocal parameters were derived from recordings, and statistically significant effects of room acoustics were verified using mixed-model analysis of variance tests. Changes in reverberation time (T20), early decay time (EDT), clarity index (C50), speech transmission index (STI), and room gain (GRG) all showed highly correlated effects on certain vocal parameters, including speaking level standard deviation, speaking rate, and acoustic vocal quality index. The results show that as T20, EDT, and GRG increased, and as C50 and STI decreased, vocal parameters tended toward dysphonic phonation. These findings increase our understanding of the impact of room acoustics on vocal production, informing room design to help mitigate unhealthy vocal exertion and, by extension, voice problems. The study provides examples of how signal processing of speech signals benefits architectural-acoustics knowledge.
In-vivo-quantitative-ultrasound assessment of thyroid nodules
Authors: Mamou Jonathan , Goundan Poorani , Rohrbach Daniel , Patel Harshal , Feleppa Ernest , Lee Stephanie
Published: November 2019

Thyroid nodules suspicious for malignancy during clinical-ultrasound (US) evaluation undergo fine-needle-aspiration biopsy (FNAB) followed by cytological evaluation and, in indeterminate cases, an additional surgical intervention or molecular testing is recommended. Quantitative ultrasound (QUS) was investigated as a non-invasive approach to detect thyroid cancer and potentially reduce the currently large number of unnecessary FNABs. RF data were acquired from 225 nodules of 208 patients using a GE Logiq E9 US equipped with a 10-MHz linear-array probe. Five QUS estimates were computed throughout each nodule. Specifically, effective scatter diameter, effective scatter concentration, midband fit, and intercept were obtained using a reference-phantom method. The Nakagami shape parameter was computed using a maximum-likelihood estimator. Mean and standard deviations (SD) of QUS estimates within nodules were used for classification. QUS-based classification performance was quantified using area-under-the-curve (AUC) values obtained from receiver-operating- characteristic analyses. An AUC value of 0.77 was obtained using the SD of intercept alone; the value increased to 0.86 when five QUS estimates were linearly combined. Our in vivo results demonstrate the potential of QUS methods to detect cancerous nodules. Ultimately, the clinical protocol could be altered to prevent FNABs of nodules highly unlikely to be malignant based on QUS analysis.
Portable acoustofluidic nebulizer
Authors: Connacher William , Jain Aditi , Stambaugh Mark , Leung Vincent W. , Friend James
Published: November 2019

The field of acoustofluidics studies the effects of acoustic waves transferred from piezoelectric solids to small volumes of fluid. The phenomenon of acoustofluidic atomization has been studied for several decades now, and one of its major proposed applications is in pulmonary drug delivery. It is well known that droplets in the 1 to 5 μm range are optimal for lung delivery. High-frequency, oriface-free, acoustic vibration has been shown to produce droplets in narrow size distributions including this range. Until now, this technology has not been practical for point-of-care. We have created the first portable acoustofluidic nebulizer as a proof of concept for this application. This device has been enabled by improved transducer design that can now be driven by standard COTS (commercial off-the-shelf) integrated circuits for efficient frequency-synthesis and power-delivery in the 5-25 MHz, 0.5–2 W range. We use a thickness mode transducer with reduced dimensions and incorporate an on-board resonance search algorithm in order to obtain a true thickness mode acoustic wave. We supply fluid from a wick in contact with the edge of the transducer and promote wetting of the surface via fine abrasion in order to obtain continuous atomization from a thin film. Our device nebulizes 0.1 ml/min of water in the critical 1 to 5 μm diameter range using a standard 3.7 V, rechargeable, lithium-ion battery.
Evolutionary algorithm-based design of acoustic metamaterials for thermal insulation
Authors: Swift S. Hales , Muehleisen Ralph T. , Chimata Raghuveer , Cherukara Matthew J. , Loeffler Troy D. , Sankaranarayanan Subramanian K.
Published: November 2019

Heat transfer at the nanoscale is an acoustic problem. In nonmetallic solids, heat is primarily carried by lattice vibrations (phonons), and its transfer can similarly be impeded by methods for manipulating vibrations familiar to acousticians. Metamaterials have seen increasing use in altering and controlling vibration. Metamaterial concepts, including periodic structuring of materials and introduction of resonant inclusions, have been used to control vibration on the macroscale, and can also affect heat transfer when implemented at nanoscale. Locally resonant materials appear to be able to address the frequency range responsible for heat transfer most easily. Control of heat transfer is of particular importance because heating and cooling buildings are among the most extensive human uses of energy, thus presenting a significant opportunity for societal benefit through increased efficiency. Even modest improvements in building insulation will result in significant energy and cost savings. In pursuit of a superior and cost-effective insulating material for building applications, an optimization of the nanostructure of a polymer metamaterial panel to reduce heat transfer is carried out using simulation in COMSOL and a genetic algorithm. Results of this research are presented here. [Funded by USDOE Office of Energy Efficiency and Renewable Energy (EERE)—Office of Building Technologies.]
Optimization on metasurface-enabled sound absorbing panels
Authors: Jing Yun , Ji Jun
Published: November 2019

An optimization scheme based on the genetic algorithm is proposed to achieve a desired sound absorption spectrum using coupling of multiple resonators at a minimum thickness. The proposed optimization strategy considers the area of supercell, the number of unit cells in a supercell and the shape of each unit cell. Besides the optimization based on the mechanism of coupled resonances, topology optimization with thermoviscous losses being taken into account is further proposed to explore the absorption performance of metasurface-enabled sound absorbing panels. A simplified set of equations and a relatively simple interpolation for the distribution of design variables make the topology optimization an viable option.
Adjoint-based, large-scale optimization of metamaterials
Authors: Bunting Gregory , Walsh Timothy F.
Published: November 2019

Harsh shock and vibration environments are commonly encountered in engineering applications involving dynamic loading. Acoustic/elastic metamaterials are showing significant potential as candidates for controlling wave propagation and isolating sensitive structural components. However, these materials have complex microstructures that must be properly designed to achieve their desired properties. Since each resonator could potentially have its own stiffness/mass properties, the design parameter space for a three-dimensional geometry quickly becomes prohibitively large for global search-based optimization strategies. This brings in the need for adjoint-based optimization. In this talk we will present strategies for adjoint-based, PDE-constrained design optimization of locally resonant elastic/acoustic metamaterials. We will present a variety of resonator geometries that can be easily optimized for wave control applications, along with fabrication details involving multi-material additive manufacturing. A variety of objective functions (time-domain, frequency-domain, and mode shape-domain) will be compared for their effectiveness in designing mechanical filters. [Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy's National Nuclear Security Administration under Contract No. DE-NA-0003525.]
Ripple depth and density thresholds: Estimate dependence on the measurement paradigm
Authors: Supin Alexander , Milekhina Olga , Nechaev Dmitry
Published: November 2019

Rippled-spectrum signals are a convenient test to measure spectro-temporal resolution of auditory stimuli. There is no commonly adopted paradigm for measurements of rippled-spectrum resolution. Test stimuli may be either rippled-spectrum signals with ripple phase changes during the signal or constant-phase rippled-spectrum signals. Reference stimuli may have either rippled or non-rippled spectra. In the present study, a direct comparison revealed that for rippled reference signals, the ripple depth thresholds were as low as 0.1 at low ripple densities; for a maximum ripple depth of 1.0, the ripple density resolution was 8 to 9 ripple/oct. For nonrippled reference stimuli, the ripple density resolution was as high as 25–30 ripple/oct; however, ripple depth thresholds were not less than 0.5 at ripple densities above 7 ripples/oct. It is hypothesized that the differences between resolution estimates obtained with different reference stimuli appear due to exploiting different cues for discrimination between test and reference stimuli, specifically, the cues provided by the excitation-pattern and temporal-processing mechanisms of frequency analysis. Discrimination between rippled test and rippled reference signals agrees with an excitation-pattern model, whereas discrimination between rippled test and non-rippled reference stimuli agrees with a temporal-processing model. [Work supported by Russian Science Foundation, Grant No. 16-15-10046.]
Effects of steady background noise on binaural pitch fusion
Authors: Lee Sabrina , Yuan Yi , Oh Yonghee
Published: November 2019

Binaural pitch fusion is the fusion of dichotic stimuli across the two ears. The current study was designed to investigate how steady background noise can influence binaural fusion. The binaural fusion ranges, the frequency ranges over which binaural fusion occurred, were measured with various levels (30—70 dB/ERBN) of the threshold-equalizing noise (Moore et al., 2004) and compared with those measured in quiet. Two interleaved adaptive procedures were used to estimate the fusion ranges at the reference frequencies of 2 and 3 kHz: Single-Interval Adjustment Matrix (SIAM; Kaernbach, 1990) and Maximum-Likelihood (ML; Green, 1992). The results show that the TEN decreases the fusion ranges to about 1.5 to 2 times narrower than those in the quiet condition. Even soft noise levels (i.e., the 30 dB/ERBN) significantly decreased fusion ranges. For some subjects, the fusion range asymptoted with a soft level and did not increase with increased noise level; for other subjects, the fusion range minimized only at the specific noise level. Both SIAM and ML procedures showed similar performance in fusion range estimation. The findings suggest that the importance of steady background noise, specifically TEN, in binaural fusion may vary across subjects. This may provide potential rehabilitation approaches to reduce broad fusion in hearing impaired listeners.
Changes in sound lateralization ability of elderly individuals when the onset conditions of pure tone of 1 kHz are varied
Authors: Morita Kazumoto , Osawa Tsukuru , Toi Takeshi
Published: November 2019

In our previous experiments, we found that the recognition of onset of the sound with Interaural Time Differences (ITDs) was inferior for the elderly in comparison with the younger participants. In the present experiment, we have conducted a test using 17 elderly and 16 young participants, in which the duration of the cosine-shaped onset of a 1 kHz pure tone that lasted one second was changed to 4 types of 1, 2, 5 and 10 ms. In addition, 9 types of ITDs (0.2, 0.4, 0.6, 0.8 ms leading to the left or right ear besides the same condition to both ears) were set. In the experiment, a reference sound indicating the front was presented followed by a test sound. Participants responded with 3 choices of the direction of the test sound compared with the reference sound: “Left,” “Same,” or “Right.” The following findings were obtained. (1) Elderly participants are more likely than younger participants to poorly lateralize when sound precedes to the right ear first than to the left. (2) For the elderly participants, the longer the cosine-shape of the onset is, the more likely direction is to be erroneously recognized.
Validation of the whisper test modified by distance as a screening test of hearing impairment for young adults
Authors: Purnami Nyilo , Wiyadi HMS , Falerina Rosa , Nadiroh Ainun , Arifianto Dhany , Nugroho Puguh S.
Published: November 2019

Pure-tone audiometry as a gold standard is difficult to perform in several places in Indonesia due to problems related to access, referral systems, and costs. Therefore, the examiner relies on the whisper test as a screening test. In this study, we evaluated the newly proposed method of whisper test by modifying the distance so that this method quite practical, simple and can be performed in a smaller room and for the large groups. The test was conducted to 618 randomly selected students (young adults). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the screening test were compared with pure tone audiometry. Based on diagnostic and screening test evaluation, the results showed that the PPV and NPV values are 13.43% and 99.27% respectively. The whisper test modified by distance yielded high sensitivity (69.23%) and high specificity (90.41%) for the screening test. This hearing screening method will be useful in identifying more hearing impairment for a huge population which helps in referral planning.
Investigation of the unsteady responses of airfoils due to small-scale motion
Authors: Catlett Matthew R. , Anderson Jason , Baeder James
Published: November 2019

Unsteady pressures, forces, and pitching moments generated by foils experiencing vibratory motion in an incompressible, attached flow configuration are studied within this work. Specifically, two-dimensional, unsteady potential flow calculations are performed on Joukowski foils of varying thickness undergoing variable amplitude, small-scale, heaving or pitching motion over a range of reduced frequencies between 0.01 and 100. These calculated results are compared directly to predictions from implementing the Theodorsen model, which treats foils as infinitely thin flat plates that shed a planar sheet of vorticity. The effects of relaxing these seemingly strict assumptions of the Theodorsen model are explored, and focus is placed on results which show deviations from the Theodorsen model. These include altered unsteady responses for finitely thick foils and non-zero mean angle of attack conditions, non-linearity of the wake of shed vorticity, and analysis of the unsteady streamwise force. Further, within the potential flow framework the particular terms which control the unsteady responses are identified.
An initial analysis of two western rivers’ turbulent-flow-induced noise
Authors: Brady James R. , Gee Kent L. , Transtrum Mark K.
Published: November 2019

This talk describes noise characteristics near turbulent sections of the Provo and Colorado Rivers in Utah. For reference, these rivers are characterized as medium-sized bedrock rivers, with Strahler orders of 5 and 7, respectively. Larson Davis 831C sound level meters were used to obtain two-second, one-third octave time histories within several meters of the bank at different locations and different times of day. Along the Provo River, the low-frequency content (below 250 Hz) varies with time of day and is likely contaminated by anthropogenic noise sources. The high-frequency noise (above 250 Hz) spectral shape is remarkably similar for every measurement; this spectrum is possibly characteristic of turbulent flow in smaller rivers. However, a measurement near a Colorado River Class III rapid reveals significantly more low-frequency spectral content, but similar high-frequency behavior. Initial efforts to correlate noise with available physical data on both river systems such as flow rates, river depths, river gradient, and terrain composition are described.
Incorporating acoustic black holes in hydrofoils
Authors: Sampath Kaushik , Sieck Caleb F. , Guild Matthew D. , Rohde Charles
Published: November 2019

Fluid-loaded structures such as turbine blades, ship hulls, and aircraft wings are required to withstand turbulent flow-induced structural vibrations and yet be lightweight. In this study, the feasibility of applying the concept of acoustic black holes (ABHs) into hydrofoils as a means to mitigate flow-induced structural vibrations is evaluated. ABHs are geometrical tapers that “trap” flexural vibrations near an ideal edge. Practical implementations of this approach involve the use of damping material near the truncated edge. Optimization of the ABH thickness profile, number of ABH elements, and the damping layer for mitigating surface vibrations is performed using finite element simulations. Select designs are then fabricated leveraging multi-material polyjet 3-D printing technology. Surface vibrations of the test samples subject to leading-edge excitations are characterized using laser Doppler vibrometry. Test results are compared with simulation data and a design framework/tool for ABH implementation in hydrofoils is formulated. [Work sponsored by the Office of Naval Research.]
Numerical simulation of flow-induced sound from a wall-mounted finite length cylinder
Authors: Lenz Brett , Magalhaes Jose F. , Suh Sanghoon
Published: November 2019

A study is conducted on the numerical simulation of flow-induced sound of a wall-mounted finite length cylinder. A circular cylinder with a length-to-diameter ratio of 22.6 was considered at a Reynolds number of 11 700. The flow field is computed using a hybrid LES/RANS model and the far-field noise is calculated using the Ffowcs Williams and Hawkings acoustic analogy. The flow and acoustic results are compared with experimental results published by Moreau and Doolan in 2013.
Effects of language proficiency in categorical perception of Mandarin Chinese tones
Authors: Cheng Bing , Zhang Wen , Zhang Yang
Published: November 2019

This study compared the perception of Mandarin Chinese lexical tones by 20 adult native Mandarin Chinese speakers and 17 Chinese as a foreign language (CFL) learners with different levels of Chinese proficiency. We were particularly interested in confirming the effects of language experience and further assessing how Chinese proficiency might influence the perception of Mandarin lexical tones. Three types of continuum were used in identification and discrimination tasks, including tone 1 (T1)/tone 2 (T2), tone 1/tone 4 (T4) and tone 2/tone 4. Unlike the native speakers of Chinese who demonstrated clear categorical perception for all the continua, the CFL learners showed reduced accuracy in identification and discrimination results. Furthermore, proficiency data correlated with categorical perception (CP) of Mandarin lexical tones, suggesting that categorical perception of key phonological contrasts in the second language can be considered as a reliable indicator of language proficiency.
Assessing the differences between monolingual and bilingual speakers in a tongue-twister task: Is there evidence for a bilingual advantage?
Authors: Dugaillard Beckie D. , Vasilita Mariana , Spinu Laura
Published: November 2019

While not uncontroversial, the claim that bilingual experience underlies certain cognitive advantages has been at the forefront of recent work. Thus, enhanced skills were associated with bilingualism in terms of multitasking, auditory encoding of sound, and resistance to dementia. Among the mechanisms potentially supporting the cognitive differences between mono- and bilinguals, those pertaining to executive function have been investigated extensively. Our study adds to a more recently initiated direction seeking to determine if there is also a connection between bilingualism and sensorimotor mechanisms. Specifically, we explore experimentally articulatory skill, expressed as accuracy, speed, and acoustic prototypicality in the production of tongue-twisters. Three groups of undergraduates (n = 40)—monolingual, early bilinguals, and late bilinguals—read artificially constructed tongue-twisters such as “kifkivkivkif” three times in succession, matching a 150 bps rhythm on a metronome. After a practice session, each participant read 64 items, many of which induced mispronunciations. The productions were manually evaluated for correctness, revealing that the monolinguals and late bilinguals outperformed the early bilinguals. In the next phase, acoustic analyses will be performed to determine more fine-grained phonetic properties, e.g., consonant duration, formant transitions, and extent of devoicing, possibly revealing different hyper-/hypoarticulation patterns in the three groups.
The identification of trained nonnative speech sounds improve after a daytime nap
Authors: Earle F. Sayako
Published: November 2019

Perceptual ability of nonnative speech sounds improves in the 24 hours that follow learning, in the absence of further training (Earle and Myers, 2015a, 2015b). These improvements are particularly salient in the morning, that is, immediately following the overnight between-session interval. These observations are moreover associated with rudimentary measures of sleep duration (Earle et al., 2017). While we have attributed these perceptual gains to memory consolidation during sleep (Marshall and Born, 2007), there yet remains the possibility that consolidation of acoustic information occurs during a relative period of absence of interfering auditory input that is related to time spent in sleep. In this study, we trained a group of college students in the identification of the Hindi dental-retroflex contrast at noon, and then recorded their electroencephalographic (EEG) activity during an in-lab nap immediately following training. We measured perceptual performance on the trained nonnative contrast immediately before and after a daytime nap. Data from a preliminary sample of 8 participants demonstrate a trending association between changes in perceptual behavior and the number of sleep spindles observed during stage N2 post-training sleep. This association may indicate the role of sleep, and hippocampal memory consolidation, in the formation of speech sound representations.
Spanish and English bilinguals: Between L1 and L2?
Authors: Ferreira Aline , Miglio Viola G.
Published: November 2019

The present study explores the vowel and intonation systems of heritage Spanish speakers in California based on a corpus of semi-directed interviews, to establish whether one language influences the other, or whether their English and for Spanish are closer to the monolingual speakers’ system of either language. There is some limited evidence that the vowel systems of Spanish in Spanish heritage speakers of Mexican descent in California is indeed very similar to the system of monolingual Mexican Spanish speakers (in pitch, duration, F1 and F2 values)—their English vowel system, however, and especially the front vowels, is not completely comparable to the published values for monolingual American English speakers’ vowels (Miglio, 2011). Intonation in bilingual Spanish has been shown to be influenced by English pitch movement, as well as signalling information structure (Gries and Miglio, 2015). This study widens the scope of the previous ones using data from natural speech as opposed to carrier sentences read out loud, and uses unpublished data from the same regional varieties of both English and Spanish, as spoken in California (monolingual English, bilingual English-Spanish), and in Mexico (monolingual Spanish) by individuals in the same age group and of comparable socio-cultural background.
Geminate attrition in the speech of Arabic–English bilinguals living in the United States
Authors: Hanini Rawan , Khudidi Anwar , Rafat Yasaman , Spinu Laura
Published: November 2019

This study explores the phenomenon of language attrition. Specifically, we investigate the phonetic properties of consonant gemination across three groups of speakers of Palestinian Arabic: monolinguals (i.e., native speakers born in Palestine who have lived there their entire life, n = 5), late bilinguals (i.e., speakers born in Palestine who emigrated to the US during their teens, n = 6), and heritage speakers (i.e., speakers of Palestinian descent, born in the US and who speak both English and Arabic in their daily lives, n = 7). All speakers were in their mid-1920s. The participants were tested using a delayed word repetition task. The stimuli comprised 158 bi-syllabic Arabic minimal and near-minimal pairs (e.g., /ħam:aːm/ “bathroom” versus /ħama:m/ “pigeon”) including long and short stops, fricatives, and sonorants. We controlled for stress and syllabic position. Distractors were also included. The acoustic analysis is underway, and consists of manually aligning the target consonants, extracting the mean consonant duration and comparing it across groups. Additional measures include voicing, aspiration, and formant transitions. The findings will enable us to address the question whether universal phonetic factors (from the perspective of Markedness Theory) have an effect on degree of attrition by specifically comparing consonants from different voicing categories and manners of articulation.
The study of the relationship between Koreans' English proficiency and vowel insertion after word-final stops in English
Authors: Lee Hyunjun , Park Wooji , Lee Seok-Chae
Published: November 2019

Vowel insertion is one of the utterance errors that Korean learners of English commit frequently. Based on this fact, the purpose of this research is to determine whether the Koreans' English proficiency affects the phenomenon of vowel insertion. To achieve it, the study investigated the relationship between the Korean speakers' English proficiency and vowel insertion in their English read speech. For analysis, Korean-Spoken English Corpus (K-SEC, made in 2004) and rated K-SEC (made in 2017) were used where 32 Korean elementary school students from Seoul and Gyeonggi province had pronounced the 6 target items that are minimal pairs (e.g. cap-cab). The speakers in these speech corpus data were also classified in one of the three different groups according to their English proficiency—Novice, Intermediate, and Advanced. It turned out that the speakers who are in the advanced level showed a tendency of the least chance of inserting a vowel after word-final voiced stops (7%) whereas 35% of the speakers who are in the novice proficiency level did so. For voiceless stops, the result was similar; the advanced group had the lowest tendency of inserting a vowel after word-final voiceless stops (4%) while novice group made 18% of vowel insertion. From these finding, it is concluded that the more proficient the Korean speakers in English, the less they are likely to insert a vowel after word-final stops.
Effects of Individual difference and L1 phonology on the identification and discrimination of American English vowels by native Japanese and Korean listeners
Authors: Nozawa Takeshi
Published: November 2019

Native speakers of Japanese and Korean identified and discriminated American English vowels /i, ɪ, ɛ, æ, ɑ, ʌ/ in four different consonantal contexts. These listeners also perceptually assimilated the American English vowels to their respective L1 vowel categories. In another session, these listeners produced /i, ɪ, ɛ, æ, ɑ, ʌ/ in two different conditions. They read aloud words on a list, and they repeated after native speakers' utterances. The results revealed that Korean listeners as well as Japanese listeners rely on durational difference to identify and discriminate /i/ and /ɪ/, but Korean listeners perceptually assimilated /i/ and /ɪ/ as roughly equally good exemplars of Korean high front vowel. Japanese listeners, on the other hand, perceived /ɪ/ as somewhat less ideal exemplar of Japanese high front vowel than /i/. However, those Japanese listeners who were sensitive to spectral differences did not outperform those who were less sensitive. Moreover, Japanese listeners sensitive to the spectral differences often misidentified /ɪ/ for /ɛ/. An MDS analysis revealed that in the identification task, listeners’ L1 phonology exercise a stronger influence than do individual differences, but in discrimination task, individual differences are as strong a factor as listeners’ L1 phonology.
The effect of word-final stops’ voicing on the vowel duration and its relation with Korean speakers' English proficiency
Authors: Park Wooji , Lee Hyunjun , Lee Seok-Chae
Published: November 2019

It has been well known that the vowels preceding voiced stops are produced durationally longer than the vowels preceding voiceless stops in English. Based on this phonetic phenomenon, this research investigates to determine whether there is any relation between the Koreans' English proficiency and the difference in the ratio of the English vowel duration before the voiced stops to the English vowel duration before the voiceless stops. For analysis, the Korean-Spoken English Corpus (K-SEC, made in 2004) and the Rated Korean-Spoken English Corpus (Rated K-SEC, made in 2017) were utilized where the 32 Korean elementary school students from Seoul and Gyeonggi province articulated the target items such as bag/back and cab/cap. These speakers were categorized into one of the three different proficiency groups (Advanced, Intermediate, and Novice) according to their speaking ability. From the findings, native English speakers were found producing the vowels before the word-final voiced stops 1.421 times longer than the vowels before the word-final voiceless stops. Similarly, in the case of the Korean speakers, they produced the vowels before the word-final voiced stops longer than the vowels before the word-final voiceless stops. However, the study couldn't discover any possible relationship between their English proficiency and the ratio of the vowel duration before the word-final voiced stops to the vowel duration before the word-final voiceless stops in English (the ratio—Advanced: 1.275, Intermediate: 1.209 and Novice: 1.25).
The acquisition of a novel accent by monolinguals and early bilinguals: Vowel epenthesis in English voiceless s-clusters
Authors: Vasilita Mariana , Dugaillard Beckie D. , Spinu Laura
Published: November 2019

Bilingualism has been linked with improved function regarding certain aspects of linguistic processing, e.g., manipulating language in terms of discrete units, novel word acquisition, and learning unfamiliar sound patterns in novel accents. Recent experimental work with non-native contrasts suggests that bilinguals have enhanced phonetic learning and speech perception abilities compared to monolinguals. We investigate phonetic learning skills in monolinguals (n = 20) and early, simultaneous bilinguals (n = 20). The subjects were trained and tested on an artificial accent of English. One the features distinguishing the novel accent from the standard variety was the presence of vocalic epenthesis in the voiceless s-clusters [sp, st, sk]. For example, words such as “spy” or “school” were pronounced as “suh-py” [səpaj] and “suh-cool” [səkul]. A total of 760 target items were evaluated manually. A score of 1 was assigned for each token produced with an epenthetic vowel between s and the following consonant, otherwise the score was 0. Early bilinguals outperformed the monolinguals on the acquisition of this pattern. Acoustic analyses are underway to assess the differences between the two groups' productions, such as quality, duration, and placement of the epenthetic vowel, as preliminary observations revealed a high number of long-distance phenomena such as [spəhaj] or [spəʔaj].
Calibrating rhythms in L1 Japanese and Japanese accented English
Authors: Wayland Ratree , Nozawa Takeshi
Published: November 2019

This study applies an automated procedure, Amplitude Envelope Modulation Spectrum (AEMS), to probe rhythmic differences between L1 Japanese and Japanese accented English. AEMS directly and automatically quantifies temporal regularities in the amplitude envelope of the speech waveform within specified frequency bands and has been shown to successfully differentiate types of dysarthria and utterances with and without code-switches. Ten native speakers of Japanese (1 male, 9 female) produced the rainbow passage in both Japanese and English. The passages will be segmented into sentences before AEMS application. The AEMS consist of the slow-rate (up to 10 Hz) amplitude modulations of the full signal and 7 octave bands ranging in center frequency from 125 to 8000 Hz. Six variables relating to peak frequency and amplitude and relative energy above, below, and in the region of 4 Hz will be calculated from each frequency bands. Discriminant function analyses (DFA) will then be performed to determine which sets of predictor variables best discriminate between the two passages.
Vowel reductions in the acquisition of English lexical stress by Kazakh-Russian bilinguals
Authors: Yakup Mahire , Kuzekova Zeinekhan
Published: November 2019

This article will focus on the vowel reductions in producing English lexical stress by Kazakh-Russian bilinguals. Even though previous research examined that Kazakh-Russian bilinguals produced English lexical stress using duration and intensity, but not fundamental frequency, using vowel reductions as cues is still a question. Since Russian and English as stress contrasted languages with vowel reductions; however, Kazakh is a fixed stress language without vowel reductions. The fourteen Kazakh-Russian bilinguals (IELTS > 7.0) produced ten minimal pairs in English in the three contexts (in sentences, fixed conditions, and isolations). We used fixed conditions as samples for analysis. Since lack of American English native speakers as a baseline, we compared the stressed syllables versus unstressed syllables based on per item (PROject versus proJECT) by measuring F1/ F2 in both syllables. The results showed that participants used vowel reductions in a variety of ways. If there is schwa reduction, participants produced correctly in which F1 and F2 were changed according to the vowel positions. Non-schwa changes produced non-consistent results in which they manipulate F1 or F2 based on the vowels, and there are wrong reductions in which/æ/produced as /ʌ/ in the example of “contract” as a final stressed word.
Advanced automobile crash detection by acoustic methods
Authors: Sim Yi Hang , Chen Yijia , Wu Lijia , Geng Xianzheng , Wan Yuxuan , Chau Kevin
Published: November 2019

Today’s automobiles are equipped with a variety of safety features. On-board acceleration, rotation, steering angle, wheel speed, and throttle position sensors are widely incorporated in electronic stability control systems for traction and steering control. Cameras and even radars are increasingly employed for imminent crash detection and autonomous emergency braking whereas airbags are deployed during an actual collision. In contrast, use of acoustic signals for automobile pre-crash and crash detection has been somewhat limited even though sounds that occur during such events can offer valuable information. For example, the high-pitch squealing caused by tire skidding can provide advance warning especially if it is caused by an adjacent car. During collision, the acoustic waves traveling along the steel car frame are 17 times faster than the speed of sound in air, which can provide information more promptly than center-mounted acceleration sensors. To fully take advantage of the high-speed acoustic signals, a real-time, wavelet-based, acoustic signal processing method with sub-millisecond precision has been developed, offering distinct advantages in sudden onset detection, temporal localization accuracy, and computational cost over existing time- and frequency-domain methods. Demonstration results on different crash scenarios will be presented, which are indicative of a substantial enhancement of crash detection performance.
A model of interior cockpit noise for the F-35A
Authors: Mobley Frank S. , Wall Alan T. , Gallagher Hilary
Published: November 2019

Characterization of environmental noise is vital to protection of hearing. A measurement campaign to understand the nature of the noise in the cockpit of fifth-generation fighter aircraft has been completed. Measurements during multiple missions for each variant of the F-35 aircraft characterized the cockpit acoustic levels during various stages of flight. Additional data collection defined the aircraft state during the acoustic data collection. An initial model of the F-35A represents the A-weighted overall sound pressure level (LA) within the cockpit by a series of random decision forest models. Sensitivity analysis conducted on these models demonstrates that airspeed and the environmental control system (ECS) flow rate are the two most important parameters determining the interior acoustic levels. However, the measurements cover a subset of the full dynamic envelope of the aircraft. Since machine-learning algorithms are susceptible to greater uncertainty where no acoustic data exists, a curve fit model defines acoustic levels throughout the envelope. This model adds the ECS flow rate to the dynamic pressure calculations and produces a more accurate model of LA within the cockpit of the F-35A. This research is sponsored, in part, by F-35 Joint Program Office.
Performance improvement of non-destructive evaluation by steering vector correlation using finite element method
Authors: Han Je-Heon
Published: November 2019

In this research, in order to improve the performance of the beamforming algorithm for a nondestructive evaluation, two kinds of steering vector correlation method using the finite element analysis are proposed. First, for non-destructive evaluation applications of reinforced concrete structures, each steering vector is obtained by calculating the responses at the measurement positions for an arbitrary position of a debonded area instead of for an arbitrary position of a source. Then, the reflection effect from the boundaries of concrete samples can be minimized. Second, for the non-destructive evaluations of plates, the finite element analysis is used to investigate the geometric-induced decay model as a function of the distance from a source by applying a curve-fitting method and the obtained steering vector is applied to the MUSIC (MUltiple SIgnal Classification) algorithm to validate its performance.
Subspace detectors for long-term analysis of blue whale vocal activity in the Indian Ocean
Authors: Pinto Nikita R. , Chandrayadula Tarun K.
Published: November 2019

The Comprehensive Test Ban Treaty Organization (CTBTO) deep water hydrophones around Diego Garcia island (H08) in the central Indian Ocean observe a number of blue whale calls. The hydrophones operational since 2002 are deployed in two groups of three (triads). The first one H08S is to the south, and the second H08N to north of the island. Not much is known about the distribution of whales in the region. The CTBTO observations are hence an opportunity to address this knowledge gap. This work builds subspace detectors to track the whales. The subspaces use the time-frequency signatures of the respective calls. There were however implementation challenges. The call-frequencies drifted across the 16 year dataset. The observed SNRs across hydrophones varied much due to fading. There were also interference issues due to multiple species vocalizing at the same time. This work extends the subspace approach to deal with these issues. The new approach tracks changing frequencies, fuses calls across each triad, and rejects interfering calls. Test results show that the new detectors are relatively robust to false alarm and improve detection rates. The work then applies the detectors to all the H08S and H08N recordings to track whale seasonality and suggest migration patterns.
Cross ambiguity function mapping of acoustic source tracks using Comprehensive Test Ban Treaty Data
Authors: Lechner David A. , Vignola Joseph F. , Guan Shane , Turo Diego
Published: November 2019

This paper presents the adaptation of the Cross Ambiguity Function Mapping (CAF- Mapping) algorithm for use in acoustics. The CAF-Mapping algorithm provides a useful means of generating a geographic visualization of acoustic data. Modifications of the algorithm for use in acoustics are explained, including use of acoustic modeling to generate propagation time differences, nonlinear grid spacing for frequency differences, location seeding using either three sensors or two sensors and two data samples, and frequency normalization. The algorithm allows discrimination between multiple acoustic signals with spatial or velocity vector variance. The presentation compares simulation results for several different types of data, then provides results that track a likely group of pygmy blue whale (Balaenoptera musculus brevicauda)using data from the Comprehensive Test Ban Treaty (CTBT) sensors off the coast of Australia. The author's affiliation with The MITRE Corporation is provided for identification purposes only and is not intended to convey or imply MITRE's concurrence with, or support for, the positions, opinions, or viewpoints expressed by the author. [Approved for Public Release; Distribution Unlimited Case 19-1301. Copyright 2019, The MITRE Corporation.]
The acoustic design of higher education music rehearsal spaces
Authors: Cooper Russell A. , Holden Mark
Published: November 2019

This paper will update our paper presented in 2007 in New Orleans which analyzed our firm's acoustic design parameters for instrumental, band and choral rehearsal rooms along with measured results. In the subsequent 12 years, we have designed and opened numerous more facilities to add to the databakse of knowledge. Acoustic design parameters such as ideal room size per ensemble type, room dimensions, room height and volume, size and openess of any reflecting clouds, permanent absorption, adjustable acoustic systems, reverberation time and client specific user preferences will be examined. Project examples will be discussed to illustrate the discussion.
A more thoughtful approach to the acoustical design of music rehearsal halls
Authors: Goodman Cameron , Kahn David
Published: November 2019

With insufficient volume, one must choose between a rehearsal hall that is either too loud or too dead. Increasing room volume helps to reduce this conflict but adds to the cost of construction. Achieving the proper balance between reverberation time, room strength and cost can be challenging. The new 70 733 GSF Music Activities Center for the at Texas A&M University (TAMU) offers four large, purpose-built rehearsal halls for musicians who participate in TAMU bands, choirs, orchestras, and jazz bands, respectively. The design was aimed at creating a balanced acoustic environment with a focus on an acoustically “safe” environment for each of the respective ensembles. The design of these halls was informed by the new Norwegian standard for music facility design, NS 8178, modelling, and close collaboration among design team members.