Pero López de Ayala: protohumanist?

What unites us in these essays is an interest in the linguistic and cultural aspects of works which are considered unimportant in the traditional scheme of nationalistic literary history but which were on the cutting edge of any national cultural scene in their own times. Translations shaped the intellectual present and future and without them many local literary trends or genres would not have developed. They were the books that were known and often read more assiduously than works written originally in Castilian, and they probably had a more pervasive influence than many creations which today we consider to be primary. I hate to admit that Ayala's translation of the De casibus had a larger reading public over a longer period of time and probably exerted more general influence than El libro de buen amor or the Siervo libre de amor. This is clearly demonstrated by the large number of medieval manuscripts and early printed editions of the De casibus which were produced in the period between 1400 and 155

Ages of young stars

Determining the sequence of events in the formation of stars and planetary systems and their time-scales is essential for understanding those processes, yet establishing ages is fundamentally difficult because we lack direct indicators. In this review we discuss the age challenge for young stars, specifically those less than ~100 Myr old. Most age determination methods that we discuss are primarily applicable to groups of stars but can be used to estimate the age of individual objects. A reliable age scale is established above 20 Myr from measurement of the Lithium Depletion Boundary (LDB) in young clusters, and consistency is shown between these ages and those from the upper main sequence and the main sequence turn-off -- if modest core convection and rotation is included in the models of higher-mass stars. Other available methods for age estimation include the kinematics of young groups, placing stars in Hertzsprung-Russell diagrams, pulsations and seismology, surface gravity measurement, rotation and activity, and lithium abundance. We review each of these methods and present known strengths and weaknesses. Below ~20 Myr, both model-dependent and observational uncertainties grow, the situation is confused by the possibility of age spreads, and no reliable absolute ages yet exist. The lack of absolute age calibration below 20 Myr should be borne in mind when considering the lifetimes of protostellar phases and circumstellar material.Comment: Accepted for publication as a chapter in Protostars and Planets VI, University of Arizona Press (2014), eds. H. Beuther, R. Klessen, C. Dullemond, Th. Hennin

Graph neural networks for sound source localization on distributed microphone networks

Distributed Microphone Arrays (DMAs) present many challenges with respect to centralized microphone arrays. An important requirement of applications on these arrays is handling a variable number of input channels. We consider the use of Graph Neural Networks (GNNs) as a solution to this challenge. We present a localization method using the Relation Network GNN, which we show shares many similarities to classical signal processing algorithms for Sound Source Localization (SSL). We apply our method for the task of SSL and validate it experimentally using an unseen number of microphones. We test different feature extractors and show that our approach significantly outperforms classical baselines.Comment: Presented as a poster at ICASSP 202

Dual input neural networks for positional sound source localization

In many signal processing applications, metadata may be advantageously used in conjunction with a high dimensional signal to produce a desired output. In the case of classical Sound Source Localization (SSL) algorithms, information from a high dimensional, multichannel audio signals received by many distributed microphones is combined with information describing acoustic properties of the scene, such as the microphones' coordinates in space, to estimate the position of a sound source. We introduce Dual Input Neural Networks (DI-NNs) as a simple and effective way to model these two data types in a neural network. We train and evaluate our proposed DI-NN on scenarios of varying difficulty and realism and compare it against an alternative architecture, a classical Least-Squares (LS) method as well as a classical Convolutional Recurrent Neural Network (CRNN). Our results show that the DI-NN significantly outperforms the baselines, achieving a five times lower localization error than the LS method and two times lower than the CRNN in a test dataset of real recordings

The Neural-SRP method for positional sound source localization

Steered Response Power (SRP) is a widely used method for the task of sound source localization using microphone arrays, showing satisfactory localization performance on many practical scenarios. However, its performance is diminished under highly reverberant environments. Although Deep Neural Networks (DNNs) have been previously proposed to overcome this limitation, most are trained for a specific number of microphones with fixed spatial coordinates. This restricts their practical application on scenarios frequently observed in wireless acoustic sensor networks, where each application has an ad-hoc microphone topology. We propose Neural-SRP, a DNN which combines the flexibility of SRP with the performance gains of DNNs. We train our network using simulated data and transfer learning, and evaluate our approach on recorded and simulated data. Results verify that Neural-SRP's localization performance significantly outperforms the baselines.Comment: Presented at Asilomar Conference on Signals, Systems, and Computer

EUCOM’s POL Capability & Capacity Gaps – Single Fuel Concept Follow On

NPS NRP Executive SummaryThis research effort will analyze fuel supply and distribution capabilities during Phase II operations in the European theater when operating under the single fuels concept. This effort will build on two prior works by the research team: the first study focused on the logistics benefit provided by the single fuel concept in the Pacific (UNCLAS); the second study explored the current logistics capability and capacity gaps surrounding POL distribution in the EUCOM theater (SECRET/NOFORN). The proposed study will explore how switching to a single fuel operational concept will impact those gaps and will address what policy could be changed and/or assets procured to lessen those capability gaps.N4 - Fleet Readiness & LogisticsThis research is supported by funding from the Naval Postgraduate School, Naval Research Program (PE 0605853N/2098). https://nps.edu/nrpChief of Naval Operations (CNO)Approved for public release. Distribution is unlimited.

EUCOM’s POL Capability & Capacity Gaps – Single Fuel Concept Follow On

NPS NRP Project PosterThis research effort will analyze fuel supply and distribution capabilities during Phase II operations in the European theater when operating under the single fuels concept. This effort will build on two prior works by the research team: the first study focused on the logistics benefit provided by the single fuel concept in the Pacific (UNCLAS); the second study explored the current logistics capability and capacity gaps surrounding POL distribution in the EUCOM theater (SECRET/NOFORN). The proposed study will explore how switching to a single fuel operational concept will impact those gaps and will address what policy could be changed and/or assets procured to lessen those capability gaps.N4 - Fleet Readiness & LogisticsThis research is supported by funding from the Naval Postgraduate School, Naval Research Program (PE 0605853N/2098). https://nps.edu/nrpChief of Naval Operations (CNO)Approved for public release. Distribution is unlimited.