Multi-modal Blind Source Separation with Microphones and Blinkies

We propose a blind source separation algorithm that jointly exploits measurements by a conventional microphone array and an ad hoc array of low-rate sound power sensors called blinkies. While providing less information than microphones, blinkies circumvent some difficulties of microphone arrays in terms of manufacturing, synchronization, and deployment. The algorithm is derived from a joint probabilistic model of the microphone and sound power measurements. We assume the separated sources to follow a time-varying spherical Gaussian distribution, and the non-negative power measurement space-time matrix to have a low-rank structure. We show that alternating updates similar to those of independent vector analysis and Itakura-Saito non-negative matrix factorization decrease the negative log-likelihood of the joint distribution. The proposed algorithm is validated via numerical experiments. Its median separation performance is found to be up to 8 dB more than that of independent vector analysis, with significantly reduced variability.Comment: Accepted at IEEE ICASSP 2019, Brighton, UK. 5 pages. 3 figure

Raking the Cocktail Party

We present the concept of an acoustic rake receiver---a microphone beamformer that uses echoes to improve the noise and interference suppression. The rake idea is well-known in wireless communications; it involves constructively combining different multipath components that arrive at the receiver antennas. Unlike spread-spectrum signals used in wireless communications, speech signals are not orthogonal to their shifts. Therefore, we focus on the spatial structure, rather than temporal. Instead of explicitly estimating the channel, we create correspondences between early echoes in time and image sources in space. These multiple sources of the desired and the interfering signal offer additional spatial diversity that we can exploit in the beamformer design. We present several "intuitive" and optimal formulations of acoustic rake receivers, and show theoretically and numerically that the rake formulation of the maximum signal-to-interference-and-noise beamformer offers significant performance boosts in terms of noise and interference suppression. Beyond signal-to-noise ratio, we observe gains in terms of the \emph{perceptual evaluation of speech quality} (PESQ) metric for the speech quality. We accompany the paper by the complete simulation and processing chain written in Python. The code and the sound samples are available online at \url{http://lcav.github.io/AcousticRakeReceiver/}.Comment: 12 pages, 11 figures, Accepted for publication in IEEE Journal on Selected Topics in Signal Processing (Special Issue on Spatial Audio

Descripción de los estadios larvales de Sigara (Tropocorixa) jensenhaarupi (Heteroptera: Corixidae), con notas acerca de su ecología

Sigara (Tropocorixa) jensenhaarupi Jaczewski is the smallest species of the subgenus ranging from 4.2–4.7 mm, and it is characterized by the absence of a strigil, the small and narrow genital capsule with a short hypandrium in males, and the shape of the abdominal tergite VII in females. This species is endemic to the Patagonian subregion (Andean region) in Argentina. A monthly sampling study was performed during a year in northern Mendoza, and additional material was collected in southern Mendoza, more precisely from Bañado Carilauquen in the Llancanelo Lake Reserve (Malargüe Department). Since little is known about the ecological requirements of S. (T.) jensenhaarupi, herein we describe its habitat, the environmental conditions and its association with other macroinvertebrates. Also, we provide a morphological description of larval stages, and provide new records of this species.Sigara (Tropocorixa) jensenhaarupi Jaczewski es la especie más pequeña del subgénero (4.2–4.7 mm), y se caracteriza por la ausencia de estrigilo, la cápsula genital masculina pequeña y angosta con el hipandro corto, y la forma característica del tergito abdominal VII en las hembras. Esta especie es endémica de la subregión Patagónica (región Andina) en Argentina. Se realizaron muestreos mensuales durante un año en el norte de la provincia de Mendoza, material adicional fue recolectado en el sur de la provincia, más precisamente en el Bañado Carilauquen en la Reserva Laguna Llancanelo (Departamento de Malargüe). Poco se conoce acerca de los requerimientos ecológicos de S. (T.) jensenhaarupi, por lo que en este trabajo describimos su hábitat, las condiciones ambientales y su asociación con otros macroinvertebrados. Además, describimos los estadios larvales y damos nuevos registros de esta especie.Fil: Melo, María Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología ; ArgentinaFil: Scheibler, Erica Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentin

Pruned Continuous Haar Transform of 2D Polygonal Patterns with Application to VLSI Layouts

We introduce an algorithm for the efficient computation of the continuous Haar transform of 2D patterns that can be described by polygons. These patterns are ubiquitous in VLSI processes where they are used to describe design and mask layouts. There, speed is of paramount importance due to the magnitude of the problems to be solved and hence very fast algorithms are needed. We show that by techniques borrowed from computational geometry we are not only able to compute the continuous Haar transform directly, but also to do it quickly. This is achieved by massively pruning the transform tree and thus dramatically decreasing the computational load when the number of vertices is small, as is the case for VLSI layouts. We call this new algorithm the pruned continuous Haar transform. We implement this algorithm and show that for patterns found in VLSI layouts the proposed algorithm was in the worst case as fast as its discrete counterpart and up to 12 times faster.Comment: 4 pages, 5 figures, 1 algorith

Pyroomacoustics: A Python package for audio room simulations and array processing algorithms

We present pyroomacoustics, a software package aimed at the rapid development and testing of audio array processing algorithms. The content of the package can be divided into three main components: an intuitive Python object-oriented interface to quickly construct different simulation scenarios involving multiple sound sources and microphones in 2D and 3D rooms; a fast C implementation of the image source model for general polyhedral rooms to efficiently generate room impulse responses and simulate the propagation between sources and receivers; and finally, reference implementations of popular algorithms for beamforming, direction finding, and adaptive filtering. Together, they form a package with the potential to speed up the time to market of new algorithms by significantly reducing the implementation overhead in the performance evaluation step.Comment: 5 pages, 5 figures, describes a software packag

Circular economy : implications for the Swiss fashion retail industry

The concept of Circular Economy is much discussed among experts and in sustainably advanced business contexts such as the 2017 Sustainability Summit in London. Several multinational companies have already joined networks to accelerate the transition into futureproofed business practices. Startups, long-established companies and scientific research are devising groundbreaking solutions to work towards this new business imperative. At its core, the Circular Economy aims at replacing the traditional, linear way of extraction, production, consumption and disposal with a circular model, where waste is considered as a precious resource for new applications. However, it seems that in the Swiss business environment the concept is rather unknown or ignored, even though it is highly relevant considering the current and forecasted macro-economic and environmental developments. “Adapt or die” is one of the more recent statements in the light of environmental pollution, the tightening of resource availability together with population growth and increasing consumption on a global level. Therefore, this Bachelor’s thesis aims to analyze the present status of and to provide guidance for the Swiss fashion retail industry. By means of a multiple-case, embedded case study design, two Swiss fashion retailers are studied within their respective ecosystems. The two units of study were selected to approach a certain degree of external analytic validity, which is the reason why a large multinational and a smaller player with Swiss tradition were chosen. Qualitative and quantitative sources of primary and secondary data are adduced, whereas solely qualitative methods are applied. The assessments are then made inductively on the basis of the business model Recovery & Recycling. It is as such one of five Accenture-devised possibilities for enterprises to embark on a circular future. It was found that successfully employing the Recovery & Recycling business model embraces decoupling in two different ways: decoupling from potentially harmful resources, the environmental perspective and, decoupling from increasingly scarce resources, the economic perspective. The Swiss fashion industry turned out to be rather advanced within the environmental perspective, yet there is room for improvement when it comes to closing the material loop from an economic perspective. Smaller players with limited means are well advised to draw on the many instruments or methods already available and to imitate larger, more advanced players. Finally, some advancements depend on breakthroughs in recycling technology and material sciences. Nevertheless, much can already be improved by efficient design of products and processes in a way that facilitates reuse and recycling

Gadamer, Heidegger, and the Social Dimensions of Language: Reflections on the Critical Potential of Hermeneutical Philosophy

Beginning with an account of recent efforts, like Georgia Warnke\u27s, to demonstrate Hans-Georg Gadamer\u27s relevance to legal theory, this Article looks at Gadamer\u27s conception of language and tradition, claiming that, while he shares important features of Heidegger\u27s thought, Gadamer productively grounds his view of language and tradition in such a way that the everyday realm of public discourse, characterized by a healthy injunction to foster reasoned debate amongst divergent perspectives and interpretations, has a vital and integral role to play. While Gadamer criticizes the Enlightenment\u27s hostility to tradition, paradoxically, his concept of linguistically mediated tradition has far more in common with Jürgen Habermas\u27s continuation of the Enlightenment project, a commitment to foster a public domain where all are vigilant against forces of domination and where claims to truth and rightness are subject to justification via a process of argumentation