Interactive Music and Synchronous Reactive Programming

This paper presents Skini, a programming methodology and an execution environment for interactive structured music. With this system, the composer programs his scores in the HipHop.js synchronous reactive language. They are then executed, or played, in live concerts, in interaction with the audience. The system aims at helping composers to find a good balance between the determinism of the compositions and the nondeterminism of the interactions with the public. Each execution of a Skini score yields to a different but aesthetically consistent interpretation. This work raises many questions in the musical fields. How to combine composition and interaction? How to control the musical style when the audience influences what is to play next? What are the possible connections with generative music? These are important questions for the Skini system but they are out of the scope of this paper that focuses exclusively on the computer science aspects of the system. From that perspective, the main questions are how to program the scores and in which language? General purpose languages are inappropriate because their elementary constructs (i.e., variables, functions, loops, etc.) do not match the constructions needed to express music and musical constraints. We show that synchronous programming languages are a much better fit because they rely on temporal constructs that can be directly used to represent musical scores and because their malleability enables composers to experiment easily with artistic variations of their initial scores. The paper mostly focuses on scores programming. It exposes the process a composer should follow from his very first musical intuitions up to the generation of a musical artifact. The paper presents some excerpts of the programming of a classical music composition that it then precisely relates to an actual recording. Examples of techno music and jazz are also presented, with audio artifact, to demonstrate the versatility of the system. Finally, brief presentations of past live concerts are presented as an evidence of viability of the system

Electrical and optical measurements of the bandgap energy of a light-emitting diode

International audienceSemiconductors materials are at the basis of electronics. Most electronic devices are made of semiconductors. The operation of these components is well described by quantum physics which is a little mysterious to students. One of the intrinsic parameters of semiconductors is their bandgap energy Eg. In the case of light-emitting diodes (LEDs) Eg fixes the colour of the light emitted by the diodes. We propose in this article a lab work allowing a comparison of Eg of a green LED obtained by both electrical and optical measurements. The two slightly different results can be explained by the theoritical knowledges of the students on solid physics and electronic devices internal architecture

Aerómetro digital basado en Arduino

El objeto de este trabajo de fin de grado surge ante la necesidad de una empresa. Esta empresa es productora de pasta de pimiento, empleada en la industria aceitunera, cuyas propiedades dependen de la concentración de cloruro cálcico en una disolución. La concentración de esta disolución se controla indirectamente mediante la densidad. Para poder monitorizar el valor de la densidad, se digitaliza el valor de la medida de un aerómetro analógico mediante un Arduino. El sensor implementado, además, permite registrar históricos de los datos obtenidos para poder hacer un control de la densidad de la mezcla con el fin de homogeneizar las propiedades de la pasta. Ya que esta es susceptible a la concentración de cloruro cálcico: para concentraciones altas la pasta cuaja rápido en el exterior, influyendo incluso en su tamaño; y si es baja, no termina el proceso de gelificación. .The aim of this final project arises from a company’s need. This company is producer of pepper paste, which is used for the olives industry, and whose propierties depend on the calcium chloride concentration in a solution. The concentration of the solution is indirectly controled through the density. In order to monitor the value of the density, the measurement value of an analogic aerometer is digitalizad by means of an Arduino. Moreover, the implemented sensor allows to record historical data, so that a control of the density can be done with the purpose of homogenize paste’s propierties. That is because it is sensitive to the calcium chloride concentration: for hight concentrations the paste settle rapidly outside, affecting even to its size; and for low ones, the gelation process does not come to an end.Universidad de Sevilla. Grado en Ingeniería de Tecnologías Industriale

An introduction to photocatalysis through methylene blue photodegradation

International audienceWe described a simple experimental setup for a lab work on the photocatalytic degradation of methylene blue by T iO 2 nanoparticles. The photocatalysis process can be used for many applications. Treatments for diluted wastewaters industries, air purifying in underground car parks, preventing fouling on glass surfaces, these are some of the things this phenomenon has the ability to do. The described experiment is easy to perform and the interpretation can be easily adapted to different level of students: from high school students demonstrating their interests on a sustainable development, to students who are getting Masters in the science department that want to propose a full explanation of all the phenomenon of the photocatalytic process. Starting by a description of the experimental setup , we analysed the photocatalyst nanoparticles and applied the Langmuir-Hinshelwood model to our experimental data. Finally we discussed shortly on the respective energetic levels of the photocatalyst semiconductor and the methylene blue

Composing and Performing Interactive Music using the HipHop.js language

International audienceSkini is a platform for composing and producing live performances with the audience participating using connected devices (smartphones, tablets, PC, etc.). The music composer creates beforehand musical elements such as melodic patterns , sound patterns, instruments, group of instruments, and a dynamic score that governs the way these basic elements behave according to events produced by the audience. The platform allows to control the musical quality of the work, even if during the concert or the performance, the audience interacts with the system giving birth to an original music creation. Skini scores are expressed in terms of constraints on events that control which musical elements are accessible to the audience and when they are available. Constraints may be instantaneous , for instance one constraint may disable violins while trumpets are playing. They may also be temporal, for instance, one constraint may prevent the piano to play more than 30 consecutive seconds. The Skini platform is implemented in Hop.js [10], for the general infrastructure and most of the user interfaces, and in HipHop.js [13], a reactive synchronous DSL, for implementing the music scores. The HipHop.js constructs, which consist of temporal operators such as parallel executions, sequences, awaits, synchronization points, and preemption, form the core implementation language for expressing Skini musical constraints. This paper presents the Skini platform and It reports about live performances and an educational project. Some musical pieces created with Skini can be found at: https://soundcloud.com/user-65171316

Charge ordering as the driving mechanism for superconductivity in rare-earth nickel oxides

Superconductivity is one of the most intriguing properties of matter described by an attractive interaction that bounds electrons into Cooper pairs. To date, the highest critical temperature at ambient conditions is achieved in copper oxides. While layered nickel oxides were long proposed to be analogous to cuprates, superconductivity was only demonstrated in 2019 albeit without clarifying the pairing mechanism. Here we use Density Functional Theory (DFT) to show that superconductivity in nickelates is driven by an electron-phonon coupling originating from a charge ordering. Due to an intrinsic electronic instability in half-doped compounds, Ni1.5+ cations dismutate into more stable Ni+ and Ni2+ cations, which is accompanied by a bond disproportionation of NiO4 complexes producing an insulating charge ordered state. Once doping suppresses the instability, the bond disproportionation vibration is sufficient to reproduce the key characteristic of nickelates observed experimentally, notably the dome of Tc as a function of doping content. These phenomena are identified if relevant degrees of freedom as well as an exchange correlation functional that sufficiently amends self-interaction errors are involved in the simulations. Finally, despite the presence of correlation effects inherent to 3d elements, nickelates superconductors appear similar to non-magnetic bismuth oxide superconductors

Mesure de la vitesse de déformation par ESPI pour l'étude de la localisation finale lors de l'essai de traction

Le but de ce travail est d'analyser le champ de vitesse de déformation que subit un matériau pendant un essai de traction. L'ESPI est utilisé pour suivre en temps réel l'évolution de la déformation locale. Cette communication s'articule sur la détection de la localisation sur une zone d'étude relativement petite. Le moment où l'une des deux bandes de cisaillement devient prédominante est mis en évidence, ainsi que le moment où cette bande, seule, continue d'exister ; ceci se produisant relativement tôt avant la rupture

Cuestiones prácticas sobre la expropiación forzosa

Treball Final del Màster Universitari en Advocacia. Codi: SRJ010. Curs acadèmic 2019-2020Este trabajo trata de exponer una serie de cuestiones prácticas referentes al justiprecio en la expropiación forzosa. En este sentido, comienza el trabajo comentando a grandes rasgos qué fundamenta la existencia del justiprecio y su equiparación a la indemnización dentro del proceso expropiatorio. Una vez expuesto esto, trataré de comentar de acuerdo a la Ley de Expropiación Forzosa, diferentes métodos valorativos del justiprecio. Otra cuestión que trata este trabajo, es la figura del obligado al pago del justiprecio, y para ello se analiza una sentencia del Tribunal Supremo que no deja dudas de quién ha de hacerse cargo de dicho pago si el beneficiario entra en concurso de acreedores. Y por último se analizan los medios existentes a la hora de replantear el justiprecio, así como una breve reseña sobre el Jurado de Expropiación

Linking the dynamic organization of the ovary with spawning dynamics in pelagic fishes

The link between the dynamic organization of the ovary and spawning dynamics was investigated in pelagic fishes with indeterminate fecundity. Αn array of laboratory methods and statistical approaches was applied to samples of gonadal material from three commercial NE Atlantic fish species: the sardine, Sardina pilchardus, the horse mackerel, Trachurus trachurus, and the mackerel, Scomber scombrus. Methods included the application of clustering analysis algorithms in histological specimens and the application of particle analysis on whole mounts. More specifically, various attributes of ovarian dynamics such as the oocyte size frequency distribution, the ratio of total to batch fecundity, the number of oocyte cohorts, and the recruitment of early secondary growth oocytes were related to historic estimates of spawning interval and oocyte growth rate. It was shown that indeterminate spawners can display varying proportions of oocytes at the size range between primary and secondary growth based on the seasonal pattern of oocyte recruitment. This finding indicates that determinacy and indeterminacy should rather be recognized as end-points along a continuum which is controlled by the degree of overlap between oocyte recruitment period and spawning period. It was also demonstrated that fishes like sardine with long spawning intervals and fast oocyte growth exhibit relatively few, clearly separated oocyte cohorts, while fishes like mackerel with shorter spawning interval display increased number of coexisting cohorts. Ultimately, these aspects may provide a proxy of spawning interval and thereby spawning frequency which is a variable of paramount importance in biomass assessments of commercial fish stocks through egg production methods.Versión del editor2,01