A Fibonacci sequence for linear structures with two types of components

We investigate binary voting systems with two types of voters and a hierarchy among the members in each type, so that members in one class have more influence or importance than members in the other class. The purpose of this paper is to count, up to isomorphism, the number of these voting systems for an arbitrary number of voters. We obtain a closed formula for the number of these systems, this formula follows a Fibonacci sequence with a smooth polynomial variation on the number of voters.Comment: All the results contained in this file are included in a paper submitted to Annals of Operations Research in October, 2008 on ocasion of the Conference on Applied Mathematical Programming and Modelling, that held in Bratislava in May, 200

Programación-1: Una asignatura orientada a la resolución de problemas

En este artículo presentamos el nuevo método docente de la asignatura Programació-1 en la Facultat d’Informàtica de Barcelona de la Universitat Politècnica de Catalunya, y damos cuenta de los resultados obtenidos durante los cinco cuatrimestres de aplicación. El curso proporciona un sistema automático de verificación de soluciones para una colección de casi 300 ejercicios cuidadosamente ordenados. Este sistema automático se usa también en la evaluación de los estudiantes durante los exámenes, que se realizan con un ordenador. Además, el sistema permite obtener datos objetivos sobre el progreso de los estudiantes a lo largo del curso.Peer Reviewe

Jutge.org

Jutge.org is an open access educational online programming judge where students can try to solve more than 800 problems using 22 programming languages. The verdict of their solutions is computed using exhaustive test sets run under time, memory and security restrictions. By contrast to many popular online judges, Jutge.org is designed for students and instructors: On one hand, the problem repository is mainly aimed to beginners, with a clear organization and gradding. On the other hand, the system is designed as a virtual learning environment where instructors can administer their own courses, manage their roster of students and tutors, add problems, attach documents, create lists of problems, assignments, contests and exams. This paper presents Jutge.org and offers some case studies of courses using it.Postprint (published version

Joc d’estructures de dades i algorismes

L'activitat consisteix en la implementació d'un jugador per a un joc d'ordinador. L'objectiu és que els estudiants hi apliquin els algorismes i estructures de dades explicats en el curs. Un joc consisteix en un tauler on es mouen agents controlats pels jugadors. Segons les seves accions, cada jugador rep una puntuació, que en finalitzar la partida en determina la classificació. En el joc no hi ha interacció humana: els programes dels estudiants estan escrits abans de cada partida. Per programar un jugador, els estudiants disposen d'informació completa sobre l'estat del tauler i de tots els jugadors. La documentació del joc explica la interfície que el programa de l'estudiant o estudianta ha d'usar per comunicar-se amb el programa principal. Els estudiants disposen d'un servidor web al qual envien els seus jugadors. A més, se'ls proporciona el codi font del joc per poder-ne desenvolupar localment la implementació. L'activitat consta de dues fases. A la primera, els estudiants han de vèncer un jugador de prova, el "beneit", implementat pel professorat i que segueix una estratègia simple. A la segona fase, els estudiants que han superat la primera participen en una eliminatòria per determinar el millor jugador del quadrimestre.Peer Reviewe

Determination of HLA-A, -B, -C, -DRB1 and -DQB1 allele and haplotype frequencies in heart failure patients

Allogeneic cell therapy; Haplotype frequency; Heart failureTeràpia cel·lular al·logènica; Freqüència haplotípica; Insuficiència cardíacaTerapia celular alogénica; Frecuencia haplotípica; Insuficiencia cardíacaAIMS: Cell therapy can be used to repair functionally impaired organs and tissues in humans. Although autologous cells have an immunological advantage, it is difficult to obtain high cell numbers for therapy. Well-characterized banks of cells with human leukocyte antigens (HLA) that are representative of a given population are thus needed. The present study investigates the HLA allele and haplotype frequencies in a cohort of heart failure (HF) patients. METHODS AND RESULTS: We carried out the HLA typing and the allele and haplotype frequency analysis in 247 ambulatory HF patients. We determined HLA class I (A, B, and C) and class II (DRB1 and DQB1) using next-generation sequencing technology. The allele frequencies were obtained using Python for Population Genomics (PyPop) software, and HLA haplotypes were estimated using HaploStats. A total of 30 HLA-A, 56 HLA-B, 23 HLA-C, 36 HLA-DRB1, and 15 HLA-DQB1 distinct alleles were identified within the studied cohort. The genotype frequencies of all five HLA loci were in Hardy-Weinberg equilibrium. We detected differences in HLA allele frequencies among patients when the etiological cause of HF was considered. There were a total of 494 five-loci haplotypes, five of which were present six or more times. Moreover, the most common estimated HLA haplotype was HLA-A*01:01, HLA-B*08:01, HLA-C*07:01, HLA-DRB1*03:01, and HLA-DQB1*02:01 (6.07% haplotype frequency per patient). Remarkably, the 11 most frequent haplotypes would cover 31.17% of the patients of the cohort in need of allogeneic cell therapy. CONCLUSIONS: Our findings could be useful for improving allogeneic cell administration outcomes without concomitant immunosuppression

Lists revisited: cache conscious STL lists

We present three cache conscious implementations of STL standard compliant lists. Up to now, one could either find simple double linked list implementations that easily cope with standard strict requirements, or theoretical approaches that do not take into account any of these requirements in their design. In contrast, we have merged both approaches, paying special attention to iterators constraints. In this paper, we show the competitiveness of our implementations with an extensive experimental analysis. This shows, for instance, 5-10 times faster traversals and 3-5 times faster internal sort.Postprint (published version

Three-level three-phase neutral-point-clamped back-to-back converter applied to a wind emulator

This paper presents a three-level three- phase neutral-point-clamped back-to-back converter applied to a wind emulator, where a wind power generator is connected to the grid through the back-to-back converter. The converter regulates the power extracted from the generator and controls how this power is injected to the grid with the desired power factor. Two phase locked loops are in charge of synchronizing the generator-side and the grid-side converters, regardless of the rotor speed of the generator. DC-link neutral point voltage balance is performed by the modulation strategy of the backto- back converter. Simulation and experimental results are provided to verify the correct performance of the system.Postprint (published version

2 transistors + 2 diodes-based PEBB designed for general applications in power electronics

This paper presents a new Power Electronic Building Block (PEBB) designed to facilitate the implementation of different power converter topologies. The proposed PEBB consists of two diodes and two transistors and it can be used to implement the most relevant power converter topologies, due to its modularity. The addition of the two diodes is an exclusive feature of the new PEBB, which permits to implement neutral point clamped (NPC) multilevel converters. The application of the PEBB to build a three-level NPC converter and a dc-dc push-pull converter is presented and detailed in the paper, and demonstrate that the presented PEBB can be useful to shorten converter development times.Peer ReviewedPostprint (published version

Jutge.org: characteristics and experiences

Jutge.org is an open educational online programming judge designed for students and instructors, featuring a repository of problems that is well organized by courses, topics and difficulty. Internally, Jutge.org uses a secure and efficient architecture and integrates modern verification techniques, formal methods, static code analysis and data mining. Jutge.org has exhaustively been used during the last decade at the Universitat Politecnica de Catalunya to strengthen the learn-by-doing approach in several courses. This paper presents the main characteristics of Jutge.org and shows its use and impact in a wide range of courses covering basic programming, data structures, algorithms, artificial intelligence, functional programming and circuit design.Peer ReviewedPostprint (author's final draft

Manual lesional de suport per al dictamen de carns fresques: espècie bovina

Espècie bovina; Carn fresca; Patologies; LesionsEspecie bovina; Carne fresca; Patologías; LesionesBovine species; Fresh meat; Pathologies; InjuriesAquest document integra un conjunt de fitxes que contenen informació sobre les lesions i patologies que l’equip de veterinaris oficials d’escorxador es troba habitualment en la carn fresca de boví a Catalunya. L’objectiu del document és posar en comú l’experiència i coneixement d’aquest equip per compartir-los amb la resta de professionals i ajudar-los així a elaborar els dictàmens sobre l’aptitud o no de la carn destinada al consum humà. En les fitxes no es pretén descriure les lesions i patologies d’una manera teòrica, sinó fer-ho de manera senzilla i molt pràctica per donar eines que ajudin a explicar com s’arriba al dictamen, quina n’ha estat la motivació i si s’ha de fer una declaració obligatòria de la malaltia. La força del document rau en un recull de fotos realitzades en el moment de la inspecció post mortem adjuntes al dictamen que es va fer de la carn fresca.Este documento integra un conjunto de fichas que contienen información sobre las lesiones y patologías que el equipo de veterinarios oficiales de matadero se encuentra habitualmente en las carnes frescas de vacuno en Cataluña. El objetivo del documento es poner en común la experiencia y conocimiento de este equipo para compartirlos con el resto de profesionales y ayudarlos así a elaborar los dictámenes sobre la aptitud o no de las carnes destinadas al consumo humano. En las fichas no se pretende describir las lesiones y patologías de una manera teórica, sino hacerlo de un modo sencillo y muy práctico para ofrecer herramientas que ayuden a explicar cómo se llega al dictamen, cuál ha sido su motivación y si debe realizarse una declaración obligatoria de la enfermedad. La fuerza del documento radica en una recopilación de fotos realizadas en el momento de la inspección post mortem adjuntas al dictamen de las carnes frescas.This document integrates a set of sheets that contain information about the injuries and pathologies that are usually found by official slaughterhouse veterinarians’ team in fresh beef in Catalonia. The objective of the document is to share the experience and knowledge of this team to share with the rest of the professionals and help them to elaborate opinions on the suitability of meat for human consumption. The files are not intended to describe injuries and pathologies on a theoretical level, but rather in a simple and very practical basis to offer tools that help explain how the opinion is reached, what its motivation is and whether a mandatory notification of the disease should be made. The strength of the document lies in a collection of photos taken during the post mortem inspection attached to the opinion on fresh meat