pp-Jones-Wenzl idempotents

For a prime number $p$ and any natural number $n$ we introduce, by giving an explicit recursive formula, the $p$-Jones-Wenzl projector ${}^p\operatorname{JW}_n$, an element of the Temperley-Lieb algebra $TL_n(2)$ with coefficients in ${\mathbb F}_p$. We prove that these projectors give the indecomposable objects in the $\tilde{A}_1$-Hecke category over ${\mathbb F}_p$, or equivalently, they give the projector in $\mathrm{End}_{\mathrm{SL}_2(\overline{{\mathbb F}_p})}(({\mathbb F}_p^2)^{\otimes n})$ to the top tilting module. The way in which we find these projectors is by categorifying the fractal appearing in the expression of the $p$-canonical basis in terms of the Kazhdan-Lusztig basis for $\tilde{A}_1$.Comment: 15 pages, 21 figures. Many minor changes. Major change of notation. Final versio

Case Study: Installing RFID Systems in Supermarkets

Radio frequency identification technology (RFID) is considered as the reference technology for wireless identification and item traceability. Supermarkets are one of those scenarios where the RFID potential can be harnessed. In theory, RFID in supermarkets shows several advantages compared with traditional barcode systems, offering real‐time inventory, stock control, cash queues, among others. In practice, its massive and global implementation is still being delayed due to the high quantity of factors that degrade the RFID system performance in these scenarios, causing uncontrolled items and identification losses and, at the end, economical losses. Some works in the scientific literature studied a single or a set of problems related to RFID performance, mostly focused on a specific communication layer: antennas and hardware design, interferences at physical layer, medium access control (MAC) protocols, security issues, or middleware challenges. However, there are no works describing in depth the set of factors affecting RFID performance in a specific scenario and contemplating the entire communication layer stack. The first challenge of this chapter is to provide a complete analysis of those physical and environmental factors, hardware and software limitations, and standard and regulation restrictions that have a direct impact on the RFID system performance in supermarkets. This analysis is addressed by communication layers, paying attention to the point of view of providers, supermarket companies, and final customers. Some of the most feasible and influential research works that address individual problems are also enumerated. Finally, taking the results extracted from this study, this chapter provides a Guide of Good Practices (GGPs), giving a global vision for addressing a successful RFID implementation project, useful for researchers, developers, and installers

Sistema de monitorización de temperatura para una cámara de co-cultivo celular para simular un procedimiento de transplante hepático

El trasplantament hepàtic és un procediment del que s’han realitzat nombrosos estudis al llarg dels anys. En aquest projecte, s’ha dissenyat i implementat un sistema per simular les condicions d’un procediment de transplantament hepàtic en una càmera de co-cultiu cel·lular, que simula les condicions fisiològiques del fetge (Liver on a Chip), per poder fer estudis sense utilitzar models animals. Un dels factors més importants per l’èxit del transplantament, que sempre ha estat lligat a la disfunció primària del fetge, ha estat la temperatura de preservació. Per poder fer futurs estudis, s’ha dissenyat i implementat un sistema de monitorització de temperatura que s’ha integrat al Liver on a Chip. El sistema de monitorització de temperatura ha estat desenvolupat amb Arduino i com a sensor s’ha utilitzat un termistor. Per la visualització de les dades s’ha realitzat una interfície gràfica d’usuari amb Matlab GUI. Posteriorment, per simular les condicions de transplantament hepàtic s’ha dissenyat un sistema que permet canviar els líquids que entren al Liver on a Chip y s’ha dissenyat el protocol a seguir. Finalment s’ha realitzat una prova experimental per validar els dos sistemes

The impact of the recent regulatory changes regarding non-financial information in Spain on the corporate reporting quality, measured by the analysts forecast accuracy

The purpose of this study is to examine whether the recent Spanish regulation on non-financial information has improved the quality of corporate reporting in the Spanish firms subject to this regulation. To this aim, this research investigates the impact of the Law 11/2018 on the analysts forecast accuracy. A higher quality in the non-financial information should provide more information about the future prospects of the companies, increasing the analysts forecast accuracy. Accordingly, this research tests the hypotheses that the Law 11/2018 has reduced either the analyst forecast error and analyst forecast dispersion, which are proxies for forecast accuracy. This research analyze a sample of 170 observations corresponding to 85 Spanish public listed companies trading during the years 2018 and 2019, before and after the forecasts could be formulated based on information complying with the Law 11/2018. A regression model has been created in order to test the hypothesis of an improvement in the forecast accuracy as a result of the enforcement of the Law 11/2018. The results show that there is no evidence to support the hypothesis that the enforcement of the Law 11/2018 has had a significant effect on improving the analyst forecast accuracy. Consequently, the conclusion of this research is that the quality of non-financial information has not improved significantly as a result of the Law 11/2018

MUST, a multicast synchronous transfer application for fast intra-campus replications

In this paper, we introduce a new multicast application called MUST (multicast synchronous transfer) that allows the replication of hard disk partitions in a fast and efficient way. The main goal of MUST is to help system administrators to easily maintain and update all computers in a lab. MUST transmits its IP packets in multicast mode, avoiding the use of unnecessary bandwidth. Unfortunately, the well known TCP transport protocol cannot be used in this multicast environment since the number of TCP flow control windows (and consequently, the number of ACK) that server should process, grow exponentially. Therefore, we also outline an alternative. multicast transport protocol specifically designed for this application. This way, the number of acknowledge frames are drastically reduced, allowing the use of MUST application in a LAN and intra-campus (directly interconnected LANs via few routers). scenarios. The application has been programmed in C language using standard kernel routines, therefore, MUST can mount almost all existing file systems. In addition, we can distribute our application world wide without incurring legal conflicts.This work has been supported by the Spanish Research Council under projects FARIP (TIC2000- 1734-C03-03) and MTCES (TIC2001-3339-C02-02)

A qué huelen las nubes? Importancia de las imágenes en las clases de Biología y Geología de 1º de la ESO

Actualmente estamos al alcance de muchos recursos tecnológicos, entre ellos los visuales y multimedia, como las imágenes y los vídeos. En el campo de la enseñanza, en concreto Biología, esto recursos en el aula no son muy utilizados por distintos motivos, entre ellos, la falta de alfabetización de los alumnos y la falta de importancia que les otorgan los profesores, sobre todo a las imágenes. Este trabajo trata de enfatizar, la importancia de las imágenes desde el punto de vista de la didáctica de las ciencias en Biología. Para ello, tras una revisión teórica, análisis de distintos libros de texto y puesta en práctica en un instituto, se muestra la justificación de la utilización de las imágenes en ciencia y los resultados se su aplicación en un aula real