Real-time massive convolution for audio applications on GPU

[EN] Massive convolution is the basic operation in multichannel acoustic signal processing. This field has experienced a major development in recent years. One reason for this has been the increase in the number of sound sources used in playback applications available to users. Another reason is the growing need to incorporate new effects and to improve the hearing experience. Massive convolution requires high computing capacity. GPUs offer the possibility of parallelizing these operations. This allows us to obtain the processing result in much shorter time and to free up CPU resources. One important aspect lies in the possibility of overlapping the transfer of data from CPU to GPU and vice versa with the computation, in order to carry out real-time applications. Thus, a synthesis of 3D sound scenes could be achieved with only a peer-to-peer music streaming environment using a simple GPU in your computer, while the CPU in the computer is being used for other tasks. Nowadays, these effects are obtained in theaters or funfairs at a very high cost, requiring a large quantity of resources. Thus, our work focuses on two mains points: to describe an efficient massive convolution implementation and to incorporate this task to real-time multichannel-sound applications. © 2011 Springer Science+Business Media, LLC.This work was partially supported by the Spanish Ministerio de Ciencia e Innovacion (Projects TIN2008-06570-C04-02 and TEC2009-13741), Universidad Politecnica de Valencia through PAID-05-09 and Generalitat Valenciana through project PROMETEO/2009/2013Belloch Rodríguez, JA.; Gonzalez, A.; Martínez Zaldívar, FJ.; Vidal Maciá, AM. (2011). Real-time massive convolution for audio applications on GPU. Journal of Supercomputing. 58(3):449-457. https://doi.org/10.1007/s11227-011-0610-8S449457583Spors S, Rabenstein R, Herbordt W (2007) Active listening room compensation for massive multichannel sound reproduction system using wave-domain adaptive filtering. J Acoust Soc Am 122:354–369Huang Y, Benesty J, Chen J (2008) Generalized crosstalk cancellation and equalization using multiple loudspeakers for 3D sound reproduction at the ears of multiple listeners. In: IEEE int conference on acoustics, speech and signal processing, Las Vegas, USA, pp 405–408Cowan B, Kapralos B (2008) Spatial sound for video games and virtual environments utilizing real-time GPU-based convolution. In: Proceedings of the ACM FuturePlay 2008 international conference on the future of game design and technology, Toronto, Ontario, Canada, November 3–5Belloch JA, Vidal AM, Martinez-Zaldivar FJ, Gonzalez A (2010) Multichannel acoustic signal processing on GPU. In: Proceedings of the 10th international conference on computational and mathematical methods in science and engineering, vol 1. Almeria, Spain, June 26–30, pp 181–187Cowan B, Kapralos B (2009) GPU-based one-dimensional convolution for real-time spatial sound generation. Sch J 3(5)Soliman SS, Mandyam DS, Srinath MD (1997) Continuous and discrete signals and systems. Prentice Hall, New YorkOppenheim AV, Willsky AS, Hamid Nawab S (1996) Signals and systems. Prentice Hall, New YorkopenGL: http://www.opengl.org/MKL library: http://software.intel.com/en-us/intel-mkl/MKL library: http://software.intel.com/en-us/intel-ipp/CUFFT library: http://developer.download.nvidia.com/compute/cuda/3_1/toolkit/docs/CUFFT_Library_3.1.pdfCUDA Toolkit 3.1: http://developer.nvidia.com/object/cuda_3_1_downloads.htmlCUDA Toolkit 3.2: http://developer.nvidia.com/object/cuda_3_1_downloads.htmlDatasheet of AC’97 SoundMAX Codec: http://www.xilinx.com/products/boards/ml505/datasheets/87560554AD1981B_c.pd

Rationing tests for drug-resistant tuberculosis - who are we prepared to miss?

BACKGROUND: Early identification of patients with drug-resistant tuberculosis (DR-TB) increases the likelihood of treatment success and interrupts transmission. Resource-constrained settings use risk profiling to ration the use of drug susceptibility testing (DST). Nevertheless, no studies have yet quantified how many patients with DR-TB this strategy will miss. METHODS: A total of 1,545 subjects, who presented to Lima health centres with possible TB symptoms, completed a clinic-epidemiological questionnaire and provided sputum samples for TB culture and DST. The proportion of drug resistance in this population was calculated and the data was analysed to demonstrate the effect of rationing tests to patients with multidrug-resistant TB (MDR-TB) risk factors on the number of tests needed and corresponding proportion of missed patients with DR-TB. RESULTS: Overall, 147/1,545 (9.5%) subjects had culture-positive TB, of which 32 (21.8%) had DR-TB (MDR, 13.6%; isoniazid mono-resistant, 7.5%; rifampicin mono-resistant, 0.7%). A total of 553 subjects (35.8%) reported one or more MDR-TB risk factors; of these, 506 (91.5%; 95% CI, 88.9-93.7%) did not have TB, 32/553 (5.8%; 95% CI, 3.4-8.1%) had drug-susceptible TB, and only 15/553 (2.7%; 95% CI, 1.5-4.4%) had DR-TB. Rationing DST to those with an MDR-TB risk factor would have missed more than half of the DR-TB population (17/32, 53.2%; 95% CI, 34.7-70.9). CONCLUSIONS: Rationing DST based on known MDR-TB risk factors misses an unacceptable proportion of patients with drug-resistance in settings with ongoing DR-TB transmission. Investment in diagnostic services to allow universal DST for people with presumptive TB should be a high priority

Magnetic Coupling in the Quiet Solar Atmosphere

Three kinds of magnetic couplings in the quiet solar atmosphere are highlighted and discussed, all fundamentally connected to the Lorentz force. First the coupling of the convecting and overshooting fluid in the surface layers of the Sun with the magnetic field. Here, the plasma motion provides the dominant force, which shapes the magnetic field and drives the surface dynamo. Progress in the understanding of the horizontal magnetic field is summarized and discussed. Second, the coupling between acoustic waves and the magnetic field, in particular the phenomenon of wave conversion and wave refraction. It is described how measurements of wave travel times in the atmosphere can provide information about the topography of the wave conversion zone, i.e., the surface of equal Alfv\'en and sound speed. In quiet regions, this surface separates a highly dynamic magnetic field with fast moving magnetosonic waves and shocks around and above it from the more slowly evolving field of high-beta plasma below it. Third, the magnetic field also couples to the radiation field, which leads to radiative flux channeling and increased anisotropy in the radiation field. It is shown how faculae can be understood in terms of this effect. The article starts with an introduction to the magnetic field of the quiet Sun in the light of new results from the Hinode space observatory and with a brief survey of measurements of the turbulent magnetic field with the help of the Hanle effect.Comment: To appear in "Magnetic Coupling between the Interior and the Atmosphere of the Sun", eds. S.S. Hasan and R.J. Rutten, Astrophysics and Space Science Proceedings, Springer-Verlag, Heidelberg, Berlin, 200

Intramural esophagic hematoma secondary to coumarinic anticoagulation: a case report

Esophagic Intramural Hematoma is an uncommon clinical condition, with a prognosis which is essentially benign. On most cases, a predisposing or precipitating factor may be seen, with the most common ones being the history of esophagic instrumentation, food impactations and thrombocytopenia. In the following manuscript, the authors present the case of a 54-years-old male with history of valve replacement surgery, who was treated at the Clinica Cardiovascular (Medellin, Colombia), with a clinical case of Intramural Esophagic Hematoma that was later confirmed to be due to a Coumarinic overanticoagulation. On this case, it is evidenced that Intramural Esophagic Hematoma is an unrecognized complication of Courmarinic anticoagulation therapy

The effect of graphite and carbon black ratios on conductive ink performance

Conductive inks based on graphite and carbon black are used in a host of applications including energy storage, energy harvesting, electrochemical sensors and printed heaters. This requires accurate control of electrical properties tailored to the application; ink formulation is a fundamental element of this. Data on how formulation relates to properties have tended to apply to only single types of conductor at any time, with data on mixed types of carbon only empirical thus far. Therefore, screen printable carbon inks with differing graphite, carbon black and vinyl polymer content were formulated and printed to establish the effect on rheology, deposition and conductivity. The study found that at a higher total carbon loading ink of 29.4% by mass, optimal conductivity (0.029 Ω cm) was achieved at a graphite to carbon black ratio of 2.6 to 1. For a lower total carbon loading (21.7 mass %), this ratio was reduced to 1.8 to 1. Formulation affected viscosity and hence ink transfer and also surface roughness due to retention of features from the screen printing mesh and the inherent roughness of the carbon components, as well as the ability of features to be reproduced consistently

Set optimization - a rather short introduction

Recent developments in set optimization are surveyed and extended including various set relations as well as fundamental constructions of a convex analysis for set- and vector-valued functions, and duality for set optimization problems. Extensive sections with bibliographical comments summarize the state of the art. Applications to vector optimization and financial risk measures are discussed along with algorithmic approaches to set optimization problems

Behavior and Impact of Zirconium in the Soil–Plant System: Plant Uptake and Phytotoxicity

Because of the large number of sites they pollute, toxic metals that contaminate terrestrial ecosystems are increasingly of environmental and sanitary concern (Uzu et al. 2010, 2011; Shahid et al. 2011a, b, 2012a). Among such metals is zirconium (Zr), which has the atomic number 40 and is a transition metal that resembles titanium in physical and chemical properties (Zaccone et al. 2008). Zr is widely used in many chemical industry processes and in nuclear reactors (Sandoval et al. 2011; Kamal et al. 2011), owing to its useful properties like hardness, corrosion-resistance and permeable to neutrons (Mushtaq 2012). Hence, the recent increased use of Zr by industry, and the occurrence of the Chernobyl and Fukashima catastrophe have enhanced environmental levels in soil and waters (Yirchenko and Agapkina 1993; Mosulishvili et al. 1994 ; Kruglov et al. 1996)

Household exposure to pesticides and bladder exstrophy in a newborn baby boy: a case report and review of the literature

© 2009 Martin et al; licensee Cases Network Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Microsatellite based genetic diversity and population structure of the endangered Spanish Guadarrama goat breed

<p>Abstract</p> <p>Background</p> <p>Assessing genetic biodiversity and population structure of minor breeds through the information provided by neutral molecular markers, allows determination of their extinction risk and to design strategies for their management and conservation. Analysis of microsatellite loci is known to be highly informative in the reconstruction of the historical processes underlying the evolution and differentiation of animal populations. Guadarrama goat is a threatened Spanish breed which actual census (2008) consists of 3057 females and 203 males distributed in 22 populations more or less isolated. The aim of this work is to study the genetic status of this breed through the analysis of molecular data from 10 microsatellites typed in historic and actual live animals.</p> <p>Results</p> <p>The mean expected heterozygosity across loci within populations ranged from 0.62 to 0.77. Genetic differentiation measures were moderate, with a mean F_STof 0.074, G_STof 0.081 and R_STof 0.085. Percentages of variation among and within populations were 7.5 and 92.5, respectively. Bayesian clustering analyses pointed out a population subdivision in 16 clusters, however, no correlation between geographical distances and genetic differences was found. Management factors such as the limited exchange of animals between farmers (estimated gene flow Nm = 3.08) mostly due to sanitary and social constraints could be the major causes affecting Guadarrama goat population subdivision.</p> <p>Conclusion</p> <p>Genetic diversity measures revealed a good status of biodiversity in the Guadarrama goat breed. Since diseases are the first cause affecting the census in this breed, population subdivision would be an advantage for its conservation. However, to maintain private alleles present at low frequencies in such small populations minimizing the inbreeding rate, it would necessitate some mating designs of animals carrying such alleles among populations. The systematic use of molecular markers will facilitate the comprehensive management of these populations, which in combination with the actual breeding program to increase milk yield, will constitute a good strategy to preserve the breed.</p