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Printers have become ubiquitous in modern office spaces, and their placement in these spaces been guided more by accessibility than security. Due to the proximity of printers to places with potentially high-stakes information, the possible misuse of these devices is concerning. We present a previously unexplored covert channel that effectively uses the sound generated by printers with inkjet technology to exfiltrate arbitrary sensitive data (unrelated to the apparent content of the document being printed) from an air-gapped network. We also discuss a series of defense techniques that can make these devices invulnerable to covert manipulation. The proposed covert channel works by malware installed on a computer with access to a printer, injecting certain imperceptible patterns into all documents that applications on the computer send to the printer. These patterns can control the printing process without visibly altering the original content of a document, and generate acoustic signals that a nearby acoustic recording device, such as a smartphone, can capture and decode. To prove and analyze the capabilities of this new covert channel, we carried out tests considering different types of document layouts and distances between the printer and recording device. We achieved a bit error ratio less than 5% and an average bit rate of approximately 0.5 bps across all tested printers at distances up to 4 m, which is sufficient to extract tiny bits of information. [ABSTRACT FROM AUTHOR]

A decrease in the frequency of two southeast Pacific blue whale song types was examined over decades, using acoustic data from several different sources in the eastern Pacific Ocean ranging between the Equator and Chilean Patagonia. The pulse rate of the song units as well as their peak frequency were measured using two different methods (summed auto-correlation and Fourier transform). The sources of error associated with each measurement were assessed. There was a linear decline in both parameters for the more common song type (southeast Pacific song type n.2) between 1997 to 2017. An abbreviated analysis, also showed a frequency decline in the scarcer southeast Pacific song type n.1 between 1970 to 2014, revealing that both song types are declining at similar rates. We discussed the use of measuring both pulse rate and peak frequency to examine the frequency decline. Finally, a comparison of the rates of frequency decline with other song types reported in the literature and a discussion on the reasons of the frequency shift are presented. [ABSTRACT FROM AUTHOR]

The thermally induced ultrasound emissions from printable semiconductor nanoparticles produced by the application of input pulses are demonstrated on different substrates. Printing processes that use dispersion liquids containing nanoparticles make it possible to generate ultrasound waves on flexible graphite sheets. We argue that the emission efficiency, which is the ratio of the ultrasound pressure to the input power, is greatly affected by the thermal effusivity of the nanoparticles, especially for the shell material in core-shell structured nanoparticles. [ABSTRACT FROM AUTHOR]

Abstract: Knowledge that can be gained from acoustic data collection in tropical ecosystems is low‐hanging fruit. There is every reason to record and with every day, there are fewer excuses not to do it. In recent years, the cost of acoustic recorders has decreased substantially (some can be purchased for under US$50, e.g., Hill et al. 2018) and the technology needed to store and analyze acoustic data is continuously improving (e.g., Corrada Bravo et al. 2017, Xie et al. 2017). Soundscape recordings provide a permanent record of a site at a given time and contain a wealth of invaluable and irreplaceable information. Although challenges remain, failure to collect acoustic data now in tropical ecosystems would represent a failure to future generations of tropical researchers and the citizens that benefit from ecological research. In this commentary, we (1) argue for the need to increase acoustic monitoring in tropical systems; (2) describe the types of research questions and conservation issues that can be addressed with passive acoustic monitoring (PAM) using both short‐ and long‐term data in terrestrial and freshwater habitats; and (3) present an initial plan for establishing a global repository of tropical recordings. [ABSTRACT FROM AUTHOR]

In this work, we examine the problem of efficiently preprocessing and denoising high volume environmental acoustic data, which is a necessary step in many bird monitoring tasks. Preprocessing is typically made up of multiple steps which are considered separately from each other. These are often resource intensive, particularly because the volume of data involved is high. We focus on addressing two challenges within this problem: how to combine existing preprocessing tasks while maximising the effectiveness of each step, and how to process this pipeline quickly and efficiently, so that it can be used to process high volumes of acoustic data. We describe a distributed system designed specifically for this problem, utilising a master-slave model with data parallelisation. By investigating the impact of individual preprocessing tasks on each other, and their execution times, we determine an efficient and accurate order for preprocessing tasks within the distributed system. We find that, using a single core, our pipeline executes 1.40 times faster compared to manually executing all preprocessing tasks. We then apply our pipeline in the distributed system and evaluate its performance. We find that our system is capable of preprocessing bird acoustic recordings at a rate of 174.8 seconds of audio per second of real time with 32 cores over 8 virtual machines, which is 21.76 times faster than a serial process. [ABSTRACT FROM AUTHOR]

Eumops maurusandEumops hansaeare rarely captured Neotropical molossid bats for which information on taxonomy, natural history, and spatial distribution are scarce. This translates into a poor understanding of their ecology and limits the delimitation of useful characters for their identification. Here, we describe records of these two molossids from the Central Brazilian Amazon, providing data on their external and craniodental morphology, DNA barcode (COI) sequences complemented by acoustic data for the species. Morphological characters, DNA sequence data and phylogenetic relationships within the genusEumopswere consistent with those previously described for both species. Echolocation call characteristics did not differ significantly so as to be useful for separatingE. maurusandE. hansaefrom other congeners. Our records are, respectively the first and the second for Central Amazonia as one individual previously attributed toEumops amazonicusfrom Manaus may be considered a junior synonym forE. hansae. These new records increase the extent of the species’ known ranges, partially filling in previous existing gaps in their distribution in central South America. Our data further suggest that these molossid bats forage in a wider range of habitats than previously thought. [ABSTRACT FROM AUTHOR]

Automatic sound recognition (ASR) is a remarkable field of research in recent years. The ability to automatically recognize sound events through computers in a complex audio environment is very useful for machine hearing, acoustic surveillance and multimedia retrieval applications. On the other hand, ASR task become highly difficult as the ambient noise levels increase and many traditional methods show very weak performance under noise. Recent studies has shown that spectrogram image features (SIF) have high performance under noise, while success rates in clean conditions are relatively lower than in the state-of-the-art approaches. In this study, after converting highly overlapped spectrograms into linear quantized images and reducing dimensions by applying various image resizing methods, feature extraction and classification are performed with convolutional neural networks (CNN), which have very high performance in image classification. In the mismatched case, the proposed method achieves a performance improvement of 4.5%, which is equivalent to a relative error reduction of 63.4%, with a classification success of 97.4%, while the multicondition training method achieves an average of 98.63% success rate. [ABSTRACT FROM AUTHOR]

An increase in the accuracy of identification of Activities of Daily Living (ADL) is very important for different goals of Enhanced Living Environments and for Ambient Assisted Living (AAL) tasks. This increase may be achieved through identification of the surrounding environment. Although this is usually used to identify the location, ADL recognition can be improved with the identification of the sound in that particular environment. This paper reviews audio fingerprinting techniques that can be used with the acoustic data acquired from mobile devices. A comprehensive literature search was conducted in order to identify relevant English language works aimed at the identification of the environment of ADLs using data acquired with mobile devices, published between 2002 and 2017. In total, 40 studies were analyzed and selected from 115 citations. The results highlight several audio fingerprinting techniques, including Modified discrete cosine transform (MDCT), Mel-frequency cepstrum coefficients (MFCC), Principal Component Analysis (PCA), Fast Fourier Transform (FFT), Gaussian mixture models (GMM), likelihood estimation, logarithmic moduled complex lapped transform (LMCLT), support vector machine (SVM), constant Q transform (CQT), symmetric pairwise boosting (SPB), Philips robust hash (PRH), linear discriminant analysis (LDA) and discrete cosine transform (DCT). [ABSTRACT FROM AUTHOR]

Smart services, one of the most intriguing areas of current Internet of Things(IoT) research, require improvement in terms of recognizing user activities. Sound is a useful medium for making decisions based on activity recognition in the smart home environment, which includes mobile devices such as sensors and actuators. Instead of visual sensors to recognize human activity, acoustic sensor data is acquired in an unobtrusive manner for greater privacy. However, multiuser activity provides a formidable challenge for acoustic data-based activity recognition systems because of the difficulty of identifying multiple sources of activity from among a variety of sounds. In our study, we propose a statistical method to detect the interval of interference, which is also known as the unexpected mesa, distinguishing activities based on the pre- and post-mesa intervals. The results suggest that the proposed method outperforms previously presented classification algorithms in terms of the accuracy of multiuser activity recognition. Future studies may utilize this method for improvement of existing smart home systems. [ABSTRACT FROM AUTHOR]

The number of Mexico's endemic porpoise, the vaquita ( Phocoena sinus), is collapsing primarily due to bycatch in illegal gillnets set for totoaba ( Totoaba macdonaldi), an endangered fish whose swim bladders are exported to China. Previous research estimated that vaquitas declined from about 567 to 245 individuals between 1997 and 2008. Acoustic monitoring between 2011 and 2015 showed a decline of 34%/year. Here, we combine visual line transect and passive acoustic data collected simultaneously in a robust spatial analysis to estimate that only 59 (95% Bayesian Credible Interval [CRI] 22-145) vaquita remained as of autumn 2015, a decrease since 1997 of 92% (95% CRI 80-97%). Risk analysis suggests that if the current, temporary gillnet ban is maintained and effectively enforced, vaquitas could recover to 2008 population levels by 2050. Otherwise, the species is likely to be extinct within a decade. [ABSTRACT FROM AUTHOR]

The urban sound environment of New York City (NYC) can be, amongst other things: loud, intrusive, exciting and dynamic. As indicated by the large majority of noise complaints registered with the NYC 311 information/complaints line, the urban sound environment has a profound effect on the quality of life of the city’s inhabitants. To monitor and ultimately understand these sonic environments, a process of long-term acoustic measurement and analysis is required. The traditional method of environmental acoustic monitoring utilizes short term measurement periods using expensive equipment, setup and operated by experienced and costly personnel. In this paper a different approach is proposed to this application which implements a smart, low-cost, static, acoustic sensing device based around consumer hardware. These devices can be deployed in numerous and varied urban locations for long periods of time, allowing for the collection of longitudinal urban acoustic data. The varied environmental conditions of urban settings make for a challenge in gathering calibrated sound pressure level data for prospective stakeholders. This paper details the sensors’ design, development and potential future applications, with a focus on the calibration of the devices’ Microelectromechanical systems (MEMS) microphone in order to generate reliable decibel levels at the type/class 2 level. [ABSTRACT FROM AUTHOR]

As the use of sounds for computer interfaces, electronic equipment and multimedia contents, has increased, the role of sound design tools has become more important. In sound retrieval, picking one sound out from huge data is troublesome for users because of the difficulty of simultaneously listening to plural sounds and sometimes there are difficulties with speech and sound recognition. Consequently, an efficient retrieval method is required for sound databases. This research proposes a system aim to deal with sound retrieval in both two cases: authenticity and normal. In the first case, authenticity, two algorithms has been develop one for building the authentication database and the second deal with user sound sample to retrieve the matched authenticated samples. In the second case normal we develop algorithm to deal with user sound sample to retrieve all the matched samples. Many techniques used in this proposed system such as Artificial Neural Network (ANN), Data Encryption Standard (DES), Multi Agent System (MAS) and Fourier transformation (FT). Using these combinations of advanced and adaptive techniques supports the system to be reliable, secure and parallel.

Extracting main melody from polyphonic music is one of the most appealing and challenging tasks in music information retrieval (MIR). In this paper, a new melody extraction method based on a modified Euclidean algorithm (MEA) is proposed. Firstly, the instantaneous frequency is adopted to gain better frequency discrimination, and the frame-wise pitch candidates are estimated based on the modified Euclidean algorithm. Next, the candidate trajectories are formed using these potential candidates, and padded by the candidate one octave above or below if there is a gap at some isolated frames. Finally, the melodic contours are extracted using the melody smoothness and salience principle. The proposed modified Euclidean algorithm can deal with diverse coprime harmonic combinations, and work well at low computational cost and memory requirement. The experimental results show that the proposed method can extract main melody extraction effectively with few pitch candidates. [ABSTRACT FROM AUTHOR]

Purpose Deficits in phonology, which are related to the organization and retrieval of speech sounds in the mental lexicon, are associated with two distinct clinical disorders, dyslexia and persistent speech delay. Research has shown associated speech perception deficits in individuals with these disorders, but the degree to which the underlying perceptual deficits overlap is unclear. In this study, we investigated how children with dyslexia, children with persistent speech delay and their typically-developing peers differed in speech perception when listening to speech stimuli that varied in non-linguistic temporal fine structure acoustic characteristics. Method Thirty-six children were classified into three groups (dyslexia, speech sound disorder, typically-developing; n = 12 in each group) based on their reading and speech articulation skills. Novel single-word sine-wave speech stimuli was aurally presented to the children. Results There were no group differences between children with dyslexia and their typically-developing peers, but the children with persistent speech delay had more difficulty than the other two groups. In particular, the children with persistent speech delay had difficulty recognizing words with limited acoustic structure when the stimuli involved a phoneme that they misarticulated in their own speech. Conclusions These results suggest a specific difficulty in the perception of temporal fine structure in children with persistent speech delay. [ABSTRACT FROM AUTHOR]

Searching sounds with text labels is often problematic and time consuming as text labels do not often describe the detailed audio content. Query by example is a way to improve the effectiveness and efficiency of sound retrieval. In this paper we propose a novel approach for sound query by example: query by vocal imitation. Vocal imitation is commonly used in human communication and can be employed for novel human-computer interaction. We propose two related systems. The supervised system addresses the retrieval problem by vocal imitation recognition. It trains a multi-class classifier using training vocal imitations of different sound classes in the library and classifies a new imitation query into one of the classes. This system thus cannot retrieve sounds that are not trained. The unsupervised system is more flexible in that it measures the feature distance between the imitation query and each sound in the library and returns sounds the most similar to the query. One challenge of designing these systems is finding an effective feature representation of imitation queries and sounds in the library. Existing handcrafted audio features may not work well given the variety of vocal imitations and the mismatch between vocal imitations and actual sounds. We propose to learn feature representations from training vocal imitations automatically using a Stacked Auto-Encoder (SAE). Experiments show that sound retrieving performance by automatically learned features outperform those carefully handcrafted ones that were used in existing systems in both supervised and unsupervised settings. [ABSTRACT FROM AUTHOR]

Viewing objects with stereoscopic displays provides additional depth cues through binocular disparity supporting object recognition. So far, it was unknown whether this results from the representation of specific stereoscopic information in memory or a more general representation of an object's depth structure. Therefore, we investigated whether continuous object rotation acting as depth cue during encoding results in a memory representation that can subsequently be accessed by stereoscopic information during retrieval. In Experiment 1, we found such transfer effects from continuous object rotation during encoding to stereoscopic presentations during retrieval. In Experiments 2a and 2b, we found that the continuity of object rotation is important because only continuous rotation and/or stereoscopic depth but not multiple static snapshots presented without stereoscopic information caused the extraction of an object's depth structure into memory. We conclude that an object's depth structure and not specific depth cues are represented in memory. [ABSTRACT FROM AUTHOR]

This paper presents a method for estimating bottom geoacoustic properties especially the sediment attenuation from information contained in normal modes of a broadband signal. Propagating modes are resolved using the time-warping technique applied to signals from light bulb sound sources deployed at ranges of 5 and 7 km in the Shallow Water '06 experiment. A sequential inversion approach is designed that uses specific features of the acoustic data that are highly sensitive to specific geoacoustic model parameters. The first feature is the modal group speed, which is inverted for seabed sound speed, density, and sediment thickness. The second feature is the modal depth function for inverting receiver depths. The third feature is related to the modal coefficient spectra, and this is inverted for source depth and sediment attenuation. In each subsequent stage, estimates from the previous stage(s) are used as known values. The sequential inversion is stable and generates estimates for the geoacoustic model parameters that agree very well with results from other experiments carried out in the same region. Notably, the inversion obtains an estimated attenuation of 0.078 dB//? in the band 120-180 Hz for the de-watered marine sediment characteristic of the continental shelf at the site. [ABSTRACT FROM AUTHOR]

Bubble sweep-down on oceanographic vessels generates acoustic perturbations. We propose in this work to characterize the sub-surface bubbles occurrence conditions from acoustic data analysis acquired during surveys in relatively shallow water with the IFREMER research vessels Thalassa and Pourquoi Pas?. The methodology of data analysis used in this work allows us to characterize the sailing conditions influence on bubble sweep-down occurrence. The correlation between sailing conditions and acoustic perturbations tends to demonstrate that the presence of bubbles under the hull is clearly related to the wind speed and natural aeration, and that surface bubbles are advected differently in the water column by the two vessels. [ABSTRACT FROM AUTHOR]

We have developed a model-based processing technique for borehole dipole S-wave logging data to estimate formation shear slowness from the data. During dipole acoustic logging, the presence of the logging tool can significantly affect the dispersion characteristics of flexural waves. Therefore, modeling the effects of the tool is essential for model-based processing. We have determined that an equivalent-tool theory using only two parameters, tool radius, and modulus, can adequately model the flexural-wave-dispersion characteristics. We used this theory, together with a calibration procedure, to determine the tool parameters to formulate an inversion method for the logging data processing. Our use of the equivalent tool theory played an important role in fitting the theoretical dispersion curve to the actual flexural-wave-dispersion data, enabling fast processing of the field acoustic data. An advantage of this model-based method is its prediction power, which, in the absence of low-frequency dispersion data, allows for predicting formation shear slowness from the low-frequency limit of the model-fitted dispersion curve. We have also developed an application procedure of the method for field-data processing and demonstrated its effectiveness in the dispersion correction using field acoustic data from fast and slow formations. [ABSTRACT FROM AUTHOR]

We propose develop a generalized algorithm for hiding audio signal using image steganography. The authors suggest transmitting short audio messages camouflaged in digital images using Principal Component Analysis (PCA) as an encryption technique. The quantum of principal components required to represent the audio signal by removing the redundancies is a measure of the magnitude of the Eigen values. The aforementioned technique follows a dual task of encryption and in turn also compresses the audio data, sufficient enough to be buried in the image. A 57Kb audio signal is decipher from the Stego image with a high PSNR of 47.49 and a correspondingly low mse of 3.3266 x 10-6 with an equalized high quality audio output. The consistent and comparable experimental results on application of the proposed method across a series of images demonstrate that PCA based encryption can be adapted as an universal rule for a specific payload and the desired compression ratio. [ABSTRACT FROM AUTHOR]

Electropalatographic and acoustic data on Catalan /Ck#C/ sequences where # is a word boundary and /k/ is preceded by /l, s, r/ and followed by /b, m, d, l, n, z, r, .../ were collected in order to test the hypothesis that the velar stop is most prone to be reduced and deleted next to consonants involving high articulatory and aerodynamic demands. Analysis results reveal the absence of a velar stop closure in about half of the sequence tokens, mostly so when /k/ occurs after /s/ and before an oral stop presumably due to the high manner of articulation requirements involved. On the other hand, /Ck#C/ sequences where a /k/ closure period is available show a prominent realization of the velar stop mostly next to /s, z/. This scenario points to two different production mechanisms for three-consonant sequences with contextual obstruents: articulatory reduction and elision, and a slowing down and an increase in articulatory salience, of the velar stop. /Ck#C/ sequences lacking an acoustic closure for /k/ were found to show a residual velar stop articulation which was implemented through an increase in cluster duration and in dorsopalatal contact at the approximate /k/ location in comparison to identical /C#C/ sequences with no /k/. [ABSTRACT FROM AUTHOR]

The present study investigates the phonology and phonetics of Galician post-vocalic velar nasals. Galician has very strict coda restrictions - it does not allow for complex codas. One exception to this restriction is found in the plurals of words ending in a nasal consonant, which add /s/ to the 'right' of a noun or adjective: man 'hand', mans 'hands'; pan 'bread', pans 'breads'. The present study puts forward a proposal, initially based on synchronic, formal phonological grounds, according to which post-vocalic, pre-/s/ nasals in plural forms are not nasal stops, but nasal glides. Their nature as nasal glides allows for their syllabification in the nucleus rather than in the coda, thus preserving (i.e., not violating) the restriction on complex codas. This proposal is then tested with a production experiment based on quantitative acoustic data. The acoustic study reveals indeed a difference in the degree of weakening of post-vocalic nasals, with pre-/s/ nasals in the plural forms showing a significantly higher degree of weakening than pre-/s/ nasals in the singular forms. The article concludes with an Optimality-Theoretic analysis of the phonological facts. [ABSTRACT FROM AUTHOR]

Model-based signal processing methods, such as matched-field processing, are concerned with exploiting the combination of the sound propagation physics in an ocean waveguide and the observation data. As such, they require accurate knowledge of the ocean acoustic environment. This paper presents an approach of environmental inversion via acoustic data assimilation (ADA), intended specifically to reconstruct the sound-speed field perturbed by linear internal waves. It exploits a variety of information sources, including direct local sound-speed measurements, an internal wave model, a full field acoustic propagation model, and acoustic pressure measurements. Compared to the previous work on ADA, four important improvements have been made: 1) a linear internal wave model is included; 2) a more realistic shallow-water environment from the Shelf Break PRIMER 1996 experiment is considered in the numerical simulations; and 3) effect of the sediment on acoustic propagation is considered in the inversion algorithm. The results further demonstrate the validity of the ADA approach. [ABSTRACT FROM PUBLISHER]

Subbottom acoustic profiler provides acoustic imaging of the subbottom structure constituting the upper sediment layers of the seabed, which is essential for geological and offshore geo-engineering studies. Delineation of the subbottom structure from a noisy acoustic data and classification of the sediment strata is a challenging task with the conventional signal processing techniques. Image processing techniques utilise the spatial variability of the image characteristics, known for their potential in medical imaging and pattern recognition applications. In the present study, they are found to be good in demarcating the boundaries of the sediment layers associated with weak acoustic reflectivity, masked by noisy background. The study deals with application of image processing techniques, like segmentation in identification of subbottom features and extraction of textural feature vectors using grey level co-occurrence matrix statistics. And also attempted classification using Self Organised Map, an unsupervised neural network model utilising these feature vectors. The methodology was successfully demonstrated in demarcating the different sediment layers from the subbottom images and established the sediments constituting the inferred four subsurface sediment layers differ from each other. The network model was also tested for its consistency, with repeated runs of different configuration of the network. Also the ability of simulated network was tested using a few untrained test images representing the similar environment and the classification results show a good agreement with the anticipated. [ABSTRACT FROM AUTHOR]

Data transmission through metallic structures is commonly required in industrial control applications. In a number of these applications, mechanically penetrating the structure to pass cables and establish a wired communication link is either impossible or undesirable. Examples of such structures include metal bulkheads, pressure vessels, or pipelines. Ultrasonic signaling has been proposed as a solution for through-metal data transfer without penetrating the structure. The reverberant nature of the through-metal channel, however, can lead to significant intersymbol interference, limiting the data rate achievable by conventional single-carrier communication techniques. In this paper, we describe a through-metal communication technique that exploits the slow-varying nature of the ultrasonic channel to implement an orthogonal-frequency-division-multiplexing-based rate-adaptive peak-to-average power ratio (PAPR) reduction algorithm. Measurements of the proposed adaptive algorithm have demonstrated transmitted throughput rates of up to 14 Mbps while reducing PAPR by up to 3 dB and maintaining a bit error rate of 10^ - 5 at average transmit powers of roughly 6 dBm. This enhancement provides the required throughput and error rate to support high-rate network applications in otherwise data-limited environments. [ABSTRACT FROM PUBLISHER]

Abstract: The continental margin off the La Plata Estuary (SE South America) is characterized by high fluvial sediment supply and strong ocean currents. High-resolution sediment-acoustic data combined with sedimentary facies analysis, AMS-14C ages, and neodymium isotopic data allowed us to reconstruct late Quaternary sedimentary dynamics in relation to the two major sediment sources, the La Plata Estuary and the Argentine margin. Sediments from these two provinces show completely different dispersal patterns. We show that the northward-trending La Plata paleo-valley was the sole transit path for the huge volumes of fluvial material during lower sea levels. In contrast, material from the Argentine margin sector was transported northwards by the strong current system. Despite the large sediment volumes supplied by both sources, wide parts of the shelf were characterized by either persistent non-deposition or local short-term depocenter formation. The location and formation history of these depocenters were primarily controlled by the interplay of sea level with current strength and local morphology. The high sediment supply was of secondary importance to the stratigraphic construction, though locally resulting in high sedimentation rates. Thus, the shelf system off the La Plata Estuary can be considered as a hydrodynamic-controlled end-member. [Copyright &y& Elsevier]

Eelgrass ( Zostera marina) is an important feature of coastal ecosystems in Atlantic Canada, providing a suite of valuable ecosystem services. These services, and its sensitivity to stressors, have prompted efforts to characterize the spatial and temporal dynamics of eelgrass landscapes in order to facilitate management and monitoring of coastal ecosystem health. Current methods for broad-scale mapping of eelgrass rely on aerial remote sensing and may not be appropriate in certain types of landscapes, particularly in turbid waters and areas lacking distinct boundaries. This study takes a novel approach to the quantification and analysis of seagrass landscape structure at multiple spatial scales using acoustic data and local spatial statistics. Data from a single-beam acoustic survey in Richibucto, New Brunswick, Canada were analyzed with geostatistical techniques and the Getis-Ord G i* local spatial statistic in order to detect statistically significant zones of high and low cover in an estuarine seagrass bed. Results showed distinct and significant patterns in seagrass cover at multiple spatial scales within a region of apparently continuous spatial cover. Boundaries between areas of high and low cover were also detected. This study demonstrates how acoustic data and local spatial statistics can be used to quantify landscape pattern and to further the application of landscape techniques in the marine environment. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we describe the variation in myctophid schools characteristics at South Georgia using multi-frequency acoustic data collected annually between November 2007 and January 2012. We studied the relationship between the proximity of land and the distribution and schooling characteristics of myctophid fish. We also examined patterns in schooling behaviour in relation to oceanographic data. Fish schools were identified using a dual-frequency dB identification method (S v120−38 kHz), where negative S v120−38 kHz is indicative of gas-bearing organisms, such as swimbladdered fish. Available net data were used to provide information on the meosopelagic fish community in the region. School morphometrics (e.g. length, thickness, area) data were extracted and pooled according to their distance from the shore (0–30km, 30–60km, 60–90km, 90–120km). A total of 578 schools were detected in the survey region and there was high variation in school backscattering strength (NASC), length, height, perimeter, depth and horizontal distribution between surveys, including distinct inter-annual variation in these parameters when surveys were conducted in the same season (2009–2012). Schools were distributed predominantly on-shelf (0–500m isobaths) during some summer surveys (2007 and 2012) and predominantly off-shelf on others (>500m isobaths; 2009, 2010 and 2011). There was also evidence of bathymetric separation in the horizontal distribution of schools. Schools observed in the late-season in 2008 had the greatest NASC, largest height and the deepest depth distribution. Most schools occurred at depths between ∼60 and 300m, but they did not occupy the same water masses during each survey. Schools became progressively thinner, shallower and acoustically weaker with increasing distance to land, whilst school length and perimeter increased correspondingly. The change in fish schooling behaviour between environments could be a response to a combination of local predatory threats over short spatial/temporal scales and differences in oceanographic conditions, such as current velocity. The trend could also be evidence of spatial habitat partitioning of myctophids, with different schooling species, or different life-stages, orientating along a bathymetric gradient at South Georgia. [Copyright &y& Elsevier]

SUMMARY For decades, biologists around the world have recorded animal sounds. As the number of records grows, so does the difficulty to manage them, presenting challenges to save, retrieve, share, and manage sounds. These challenges are complicated by the fact that animal sound recordings have specific peculiarities, associated to the context in which the sound was recorded. For example, sounds emitted by individuals that are in groups may be different from ones emitted by isolated individuals. Although these characteristics may be relevant to biologists, they are seldom explicit in the recording metadata. This paper discusses our ongoing research on the management of sound recordings, considering factors such as environmental or social contexts, which are not treated by current systems. This work exploits retrieval based on context analysis. Query parameters include context variables that are dynamically derived using public services and ontologies associated with sound recording metadata. Part of the results have been validated through a web prototype, discussed in the text. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The DeepVision stereo camera system collects a continuous record of colour images of all fish passing inside the extension of a trawl. Ninety-eight percent of 1729 fish captured while trawling could be identified to species from images, and lengths could be estimated from the images of 96% of the fish identified. A landmark distance technique developed to estimate lengths from images containing incomplete, curved, or obscured fish introduced <1% error for the majority of individuals (maximum 5% error). The technology can greatly increase the scope of information collected during trawl sampling, including documenting fine-scale distribution of individual fish and species overlap. Such information can aid in interpreting acoustic data and fine-scale community composition and could be collected with an open codend trawl, greatly reducing sampling mortality. Images are easily archived, providing an opportunity to quality check the raw data and revisit datasets originally collected for different purposes. Adaptation of the technology for commercial fisheries could reduce the catch of unwanted species and sizes. [ABSTRACT FROM AUTHOR]

Conventionally, acoustic imaging has been performed using a single frequency or a limited number of frequencies. However, the rich information on surface profiles, structures hidden under surfaces and material properties of objects may exhibit frequency dependence. In this study, acoustic imaging on object surface was conducted over a wide frequency range with a fine frequency step, and a method for displaying the acquired multi-spectral acoustic data was proposed. A complicated rigid surface with different profiles was illuminated by sound waves sweeping over the frequency range from 1 to 20 kHz with a 30 Hz step. The reflected sound was two-dimensionally recorded using a scanning microphone, and processed using a holographic reconstruction method. The two-dimensional distributions of obtained sound pressure at each frequency were defined as 'multi-spectral acoustic imaging data'. Next, the multi-spectral acoustic data were transformed into a single RGB-based picture for easy understanding of the surface characteristics. The acoustic frequencies were allocated to red, green and blue using the RGB filter technique. The depths of the grooves were identified by their colours in the RGB image. [ABSTRACT FROM AUTHOR]

Abstract: This study addresses the problem of identifying in-set versus out-of-set speakers in noise for limited train/test durations in situations where rapid detection and tracking is required. The objective is to form a decision as to whether the current input speaker is accepted as a member of an enrolled in-set group or rejected as an outside speaker. A new scoring algorithm that combines log likelihood scores across an energy-frequency grid is developed where high-energy speaker dependent frames are fused with weighted scores from low-energy noise dependent frames. By leveraging the balance between the speaker versus background noise environment, it is possible to realize an improvement in overall equal error rate performance. Using speakers from the TIMIT database with 5s of train and 2s of test, the average optimum relative EER performance improvement for the proposed full selective leveraging approach is +31.6%. The optimum relative EER performance improvement using 10s of NIST SRE-2008 is +10.8% using the proposed approach. The results confirm that for situations in which the background environment type remains constant between train and test, an in-set/out-of-set speaker recognition system that takes advantage of information gathered from the environmental noise can be formulated which realizes significant improvement when only extremely limited amounts of train/test data is available. [Copyright &y& Elsevier]

The effects of laryngeal specification on the timing of supra-laryngeal articulations have so far received little attention. Previous research has shown that German-but not French-mixed-voicing clusters are produced with less articulatory overlap than phonologically fully voiced clusters. Articulatory and acoustic data of labial and velar stops as simple onsets and in stop + /l/ clusters are examined to probe the causes for this cross-linguistic difference in the light of the different voicing implementations of French and German. The absence of overlap in German mixed-voicing clusters is attributed to the requirement of a time slot for the stop's aspiration phase. Since French does not commonly have aspirated stops, French clusters are expected to pattern with the voiced German clusters. The results confirm that voicing patterns established for simple onsets in the literature in terms of voice onset time of both German and French also obtain in clusters. Furthermore, the data show that contrary to the expectations French clusters pattern with German mixed-voicing clusters. This low degree of overlap in both voiceless and voiced French clusters indicates that overlap is restricted by aerodynamic requirements which result from the implementations of the voicing contrast. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes ongoing work to investigate the development of a complex system designed for extracting information from large acoustic datasets. The system, called DeLMA is based on integrating advanced machine learning with high performance computing (HPC). The goal of this work is to provide the capability to accurately detect and classify whale sounds in large acoustics datasets collected using underwater sensors. The case study for this work is focused on detecting the acoustic communication signals of the North Atlantic Right Whale, Eubalaena glacialis, and uses data collected in the Stellwagen Bank National Marine Sanctuary (SBNMS), USA. A summary of the work done for developing a complex detection-classification system and brief description of several algorithms that are used for classifying whale sounds will be covered. A brief discussion on how standard detection algorithms can be incorporated, with no special modifications, into the HPC system for analysis will be mentioned, and two new right whale detection methods are presented, based on continuous region analysis (CRA) and histogram of oriented gradients (HOG). This paper presents a first-hand look at applying the DeLMA system and these algorithms on a large dataset containing over 60,000 channel-hours of acoustic data from the SBNMS. Results from these new detection methods are compared against Baseline algorithms. With the development of the DeLMA system, sound archives can now be explored using a powerful distributed processing architecture. This advancement will allow for rapid execution and visualization of the data using seasonal graphs called diel plots, which show the distribution of detections on a time-of-day vs. time-of-year plane. Diel plots of Baseline, CRA and HOG algorithm results reveal various large-scale features of the seasonality of whale calling behavior. Results are summarized and the authors discuss future areas for study, especially those relate to handling other big passive acoustic data projects. [Copyright &y& Elsevier]

Abstract: Electroglottographic and acoustic data for Catalan three-consonant clusters composed of a word- and syllable-final C1C2 sequence and an underlyingly voiced C3 in word- and syllable-initial position were collected in order to verify whether a regressive voicing assimilation process operates on all obstruents placed at the C2 and C1 sites. Data reveal the presence of low percentages of vocal fold vibration during final stops and fricatives, C3-dependent regressive voicing effects occurring to some extent during C2 but not during C1, and a more robust voicing interaction involving C1 and C2 and thus consonants placed within the same syllable and the same word. Moreover, except for perceptually and/or aerodynamically conditioned cases, voicing effects were found to be triggered by sonorants rather than by obstruents and the trill /r/ in agreement with the predictions of the Degree of Articulatory Constraint (DAC) model of coarticulation. Acoustic data for three-consonant cluster pairs differing in the underlying C3 voicing status show that speakers may use C2 duration and intensity (but not C1 or preceding vowel duration) as voicing cues. Taken together these results suggest that voicing assimilation in Catalan three-consonant cluster cannot be modeled as a long-distance regressive process, and is strongly dependent on syllable/word affiliation and on the manner and place of articulation characteristics of the consonants in the cluster. [Copyright &y& Elsevier]

Many fixed oceanographic instruments and observing systems are deployed in the water column or on the seafloor for extended periods of time without any expression at the sea surface. To routinely communicate with such subsurface instruments in the deep ocean, here a system is presented that uses underwater gliders and commercially available acoustic modems for this task and its use is demonstrated with subsurface moorings and inverted echo sounders plus bottom pressure sensor (PIES). One recent glider mission spent 31 days in data retrieval dives, capturing 2 MB of error-free subsurface data. To acquire this volume, a total of 2.65 MB (including all retransmissions) were sent, with a success rate of 75%. A model for the energy usage of each phase of modem function was derived from laboratory measurements. While the model predicts that the glider would expend 0.21 J to acquire each data byte, the actual consumption of the glider in the field is 0.49 J byte−1. The inefficiency is due to overhead associated with establishment of the acoustic link and with the resending of data that is received with errors. Including all the time for negotiating the acoustic link and for the retransmission of erroneous data, the net data throughput are around 3 bytes s−1 in spite of the modem operating at 140 to 600 baud. Even with these limitations, the technique has shown to be useful and is being utilized routinely in a research project in the California Current to obtain data from horizontal distances up to 7 km from an instrument at depths up to 4000 m, transferring on average 6 kB of data in a day of acoustic communications. [ABSTRACT FROM AUTHOR]

The author describes and evaluates a Bayesian method to reconstruct three-dimensional toothed whale trajectories from a series of echolocation signals. Localization by using passive acoustic data (time of arrival of source signals at receptors) is assisted by using visual data (coordinates of the whale when diving and resurfacing) and tag information (movement statistics). The efficiency of the Bayesian method is compared to the standard minimum mean squared error statistical approach by comparing the reconstruction results of 48 simulated sperm whale (Physeter macrocephalus) trajectories. The use of the advanced Bayesian method reduces bias (standard deviation) with respect to the standard method up to a factor of 8.9 (13.6). The author provides open-source software which is functional with acoustic data which would be collected in the field from any three-dimensional receptor array design. This approach renews passive acoustics as a valuable tool to study the underwater behavior of toothed whales. [ABSTRACT FROM AUTHOR]

The article presents a study on the survey of cetacean visual and acoustic observation in Maldives during the 2003 and 2004 seasons of northeast monsoon. The study collected biopsy sperm whales samples during the 72 days of survey of 10,915 track line kilometers area. It says that the study performed the visual survey by the naked eye of one or two observers, while the acoustic detections were made by a 100 meter long hydrophone array, contained with two Benthos AQ4 hydrophone units with Benethos AQ201 pre-amplifiers. Result shows total sightings of 157 and acoustic detection of 1,461 of the 16 cetacean species. It mentions that the commonly sighted species include Risso's dolphin, spinner dolphin, and sperm whale.

We present anatomic and acoustic data from a pilot study on the Finnish vowels [a, e. I, o, u, y. æ. ø].¹ The data were acquired simultaneously with 3D magnetic resonance imaging (MRI) and a custom built sound recording system. The data consist of a single static repetition of each vowel with constant F0. The imaging sequence was 7.6 s long and had an isotropic voxel size of 1.8 mm. We report results of listening tests and acoustic analysis of audio data as well as manual analysis of MR images. [ABSTRACT FROM AUTHOR]

Based on co-seismic displacements recorded by terrestrial GPS stations and seafloor GPS/acoustic stations, the static slip model of the 2011 M 9.0 Tohoku earthquake was determined by inverting the data using a layered earth model. According to a priori information, the rupture surface was modeled with a geometry that is close to the actual rupture, in which the fault dip angle increases with depth and the fault strike varies with the trend of the trench. As shown by the results inferred from the joint inversion, the 'geodetic' moment is 3.68 × 10 N m, corresponding to M 9.01, and the maximum slip is positioned at a depth of 13.5 km with a slip magnitude of 45.8 m. Rupture asperities with slip exceeding 10 m are mainly distributed from 39.6 to 36.97°N, over a length of almost 240 km along the trench. The slip was mostly concentrated at depths shallower than 40 km, up-dip of the hypocenter. 'Checkerboard' tests reveal that a joint inversion of multiple datasets can resolve the slip distribution better than an inversion with terrestrial GPS data only-especially when aiming to resolve slip at shallow depths. Thus, the joint inversion results obtained by this work may provide a more reliable slip model than the results of other studies that are only derived from terrestrial GPS data or seismic waveform data. [ABSTRACT FROM AUTHOR]

The article deals with music information retrieval (music search) and its relations to video-sharing websites. First of all, the basic terms of musical terminology and important properties of sound recordings are defined. These characteristics influence success of music retrieval. Authors generated (but sources respecting) separation of music search methods and its brief introduction is stated below. Then the relations between this kind of searching and video-sharing websites are explained. Core of the article consist of practical introduction of analysis results of two websites made for music search, whereas different methods of music search are closely introduced, including the examples. In conclusion, author of the article summarises, evaluates and comments the different methods of music search, including personal experiences with the websites, focusing on music search. [ABSTRACT FROM AUTHOR]

The feeding migration of Norwegian spring-spawning herring was studied in relation to prey abundance and environmental factors that may affect their feeding migration. Temperature, salinity, chlorophyll a, nitrate concentration, abundance of Calanus finmarchicus, zooplankton biomass, acoustic data on herring and trawl samples were collected during four basin-scale surveys in the Norwegian Sea from April to August 1995. Herring abundance was positively associated with the overwintering population of C. finmarchicus. We suggest that spatial gradients and temporal dynamics of the seasonal ascent of the C. finmarchicus overwintering generation provide stimuli for and affect the feeding migration of herring. The clockwise migration pattern of herring, observed during the 1990s, can be explained by delayed ascent and development of C. finmarchicus toward the west and north in the Norwegian Sea. We further suggest that herring leave a specific area before their zooplankton prey is depleted. The first generation of C. finmarchicus likely has a minor influence in directing the herring feeding migration due to the low abundance of older stages available as prey. The feeding migration was constantly directed toward colder water, and temperature probably has a secondary effect on herring distribution. [ABSTRACT FROM AUTHOR]