Topics on heavy baryon chiral perturbation theory in the large N_c limit

We compute nonanalytical pion-loop corrections to baryon masses in a combined expansion in chiral symmetry breaking and 1/N_c, where N_c is the number of colors. Specifically, we compute flavor-27 baryon mass splittings at leading order in chiral perturbation theory. Our results, at the physical value N_c=3, are compared with the expressions obtained in heavy baryon chiral perturbation theory with no 1/N_c expansion.Comment: 7 pages. Based on a talk given at 8th Mexican Workshop on Particles and Fields, Zacatecas, Mexico, 14-20 Nov 2001. To appear in the proceeding

Audio application based on FreeRTOS operating system

This current report describes in detail how the Quartet code for a Microchip PIC18 microcontroller, developed by Pere Domenech in his Final Degree Project, has been migrated to a Microchip PIC24 microcontroller. The original Real Time Operating System has also been migrated from OSA RTOS to FreeRTOS. The RTOS modification will allow future upgrades without the need to change the RTOS. The Quartet software is an audio synthesizer which uses a low-pass filtered PWM output to create a mono audio signal. The original code has 3 different instruments and 4 voices: Bass, Violin, Guitar 1 and Guitar 2. Each instrument has its own sound, specific waveform and envelope. Each voice has its own score. The 4 voices are mixed during the synthesis and played through a single PWM microcontroller output. This report explains step by step the software migration process: Operating System migration, Compiler migration and Microcontroller Instructions migration. The process is explained in detail. Therefore, it is highly recommended to read it while studying the final PIC24 Quartet code. At the end of the report, the hardware validation and experimental modifications are explained. Finally, some future improvements, limitations and suggestions are commented. This project is a continuation of the Quartet code for microcontrollers but it is clear that more improvements and modifications will be done in the future

Alternative Effects of Antidumping Policy: Should Mexican Authorities be Worried?

Administered protection is not the only outcome of antidumping measures. This paper suggests a basic model of repeated interaction between a domestic and a foreign firm. Competing in prices in the importing market, antidumping action serves as the means to enforce and sustain tacit collusion between the firms. The main result is that price distortions by antidumping policy are a departure point for the achievement of the collusive outcome. Discount factors of future profits are altered relative to those observed under free trade, delaying domestic firm’s propensity to collude and prompting foreign firm’s.price competition, repeated interaction, tacit collusion, antidumping

CARPe Posterum: A Convolutional Approach for Real-time Pedestrian Path Prediction

Pedestrian path prediction is an essential topic in computer vision and video understanding. Having insight into the movement of pedestrians is crucial for ensuring safe operation in a variety of applications including autonomous vehicles, social robots, and environmental monitoring. Current works in this area utilize complex generative or recurrent methods to capture many possible futures. However, despite the inherent real-time nature of predicting future paths, little work has been done to explore accurate and computationally efficient approaches for this task. To this end, we propose a convolutional approach for real-time pedestrian path prediction, CARPe. It utilizes a variation of Graph Isomorphism Networks in combination with an agile convolutional neural network design to form a fast and accurate path prediction approach. Notable results in both inference speed and prediction accuracy are achieved, improving FPS considerably in comparison to current state-of-the-art methods while delivering competitive accuracy on well-known path prediction datasets.Comment: AAAI-21 Camera Read

The acoustic, the digital and the body: a survey on musical instruments

This paper reports on a survey conducted in the autumn of 2006 with the objective to understand people's relationship to their musical tools. The survey focused on the question of embodiment and its different modalities in the fields of acoustic and digital instruments. The questions of control, instrumental entropy, limitations and creativity were addressed in relation to people's activities of playing, creating or modifying their instruments. The approach used in the survey was phenomenological, i.e. we were concerned with the experience of playing, composing for and designing digital or acoustic instruments. At the time of analysis, we had 209 replies from musicians, composers, engineers, designers, artists and others interested in this topic. The survey was mainly aimed at instrumentalists and people who create their own instruments or compositions in flexible audio programming environments such as SuperCollider, Pure Data, ChucK, Max/MSP, CSound, etc

Baryon semileptonic decays: the Mexican contribution

We give a detailed account of the techniques to compute radiative corrections in baryon semileptonic decays developed over the years by Mexican collaborations. We explain how the method works by obtaining an expression for the Dalitz plot of semileptonic decays of polarized baryons including radiative corrections to order ${\mathcal O}(\alpha q/\pi M_1)$, where $q$ is the four-momentum transfer and $M_1$ is the mass of the decaying baryon. From here we compute the totally integrated spin angular asymmetry coefficient of the emitted baryon and compare its value with other results.Comment: 10 pages. Prepared for the Commemorative Volume of the Divison of Particles and Fields of the Mexican Physical Societ

Modelo experimental de correlación potencia-tiempo-daño de los efectos de la radiofrecuencia

Se publican los resultados de un modelo animal para evaluar los efectos de la radiofrecuencia en base a los valores de potencia y tiempo de exposición.Introducción: La radiofrecuencia es la terapéutica de primera elección para tratar una amplia variedad de arritmias. Objetivo: Demostrar que la radiofrecuencia produce daño limitado y determinar la correlación entre potencia-tiempo- daño. Material y métodos: Estudio prospectivo, experimental. Se conformaron dos grupos de once perros cada uno. A través de la vena femoral derecha se introdujo un electrocatéter, colocando la punta en la cavidad auricular derecha. Por medio de control digital, se emitió una descarga con potencia y tiempo previamente seleccionados. El área de necrosis se midió microscópicamente. El análisis estadístico se hizo con modelo parabólico. Resultados: En el modelo parabólico con tiempo constante, el error estándar fue de 0.3750. Conclusiones: Los resultados confirman que las lesiones producidas por la radiofrecuencia son limitadas y predecibles, y sugieren que el área de lesión parece correlacionar mejor con la potencia en un modelo parabólico.Coordinación de Investigación de la Universidad Autónoma del Estado de México