Cooperative strategies for imperfect CSI scenarios based on distributed Alamouti

Les comunicacions cooperatives estan guanyant un gran interès en les comunicacions modernes degut a que permeten millorar la transmissió dʼinformació entre un emissor i un receptor utilitzant una sèrie de terminals situats entre ells. Aquest projecte és un estudi complet del sistemes cooperatius, analitzant el seu rendiment i comparant lʼús dʼun sol dʼaquests terminals amb lʼús del codi Alamouti, que utilitza dos terminals. Primer hi ha una introducció als sistemes cooperatius i a la teoria de la informació. Després hem estudiat un sistema cooperatiu amb la teoria de la informació com a base, en termes de probabilitat de fallada del sistema, i posteriorment lʼhem adaptat a un sistema cooperatiu real utilitzant una modulació QPSK, estudiant la seva probabilitat dʼerror de paquet. Finalment es proposen diversos protocols que permeten millorar el rendiment del sistema cooperatiu estudiat.

Cooperative learning: learning to cooperate, cooperating to learn

This research project is an attempt to give arguments in favour of using cooperative learning activities in FL classrooms as an effective approach to learning. The arguments offered are presented from two different perspectives: the first one is based on the empirical study of three students working together to achieve a common goal. The second one is a compilation of the trainee teacher's experiences during her practicum periods in a high school regarding group work. This part is illustrated by some examples that emphasize that cooperative learning can facilitate learning, promote socialisation and increase students' self-esteem

The learning process as a cooperative task among teachers and students

This research project gathers several ideas and guidelines on professional improvement as a teacher. This study includes two empirical studies. The first one focuses mainly on the teacher's figure. It is meant to be a study of the several resources that the teacher uses in order to construct the student's knowledge in an English classroom context. The second empirical study focuses on the students. It is a study on how students learn cooperatively by analyzing their oral productions when working in small groups

How to avoid gender bias in classroom interaction? A cooperative learning experience

This project aims to analyse the kind of questions the teacher asks students in order to encourage them to participate in her classes. Consequently, the researcher has read relevant literature and has analysed a short excerpt of a video recorded during her first practicum. She has also analysed a number of activities carried out during her second practicum in order to find out if she had improved her questioning skills in the classroom

A cooperative appproach to queue allocation of indivisible objects

We consider the allocation of a finite number of indivisible objects to the same number of agents according to an exogenously given queue. We assume that the agents collaborate in order to achieve an efficient outcome for society. We allow for side-payments and provide a method for obtaining stable outcomes.

Rational sabotage in cooperative production

In this paper we consider a model of cooperative production in which rational agents have the possibility to engage in sabotage activities that decrease output. It is shown that sabotage depends on the interplay between the degree of congestion, the technology of sabotage, the number of agents the degree of meritocracy and the form of the sharing rule. In particular it is shown that, ceteries paribus, meritocratic systems give more incentives to sabotage than egalitarian systems. We address two questions: The degree of meritocracy that is compatible with absence of sabotage and the existence of a Nash equilibrium with and without sabotage.

RECERCAT. El Dipòsit de la Recerca de Catalunya

Seguint la tendència mundial de crear dipòsits institucionals d'accés lliure per recopilar i preservar els documents d'investigació generats en les institucions acadèmiques, el CESCA i el CBUC han posat en funcionament RECERCAT. RECERCAT és un dipòsit cooperatiu de documents digitals que inclou la literatura de recerca de les universitats i dels centres d'investigació de Catalunya, com ara articles encara no publicats (preprints), comunicacions a congressos, informes de recerca, working papers, projectes de final de carrera, memòries tècniques, etc. La comunicació pretén explicar els processos que s'han seguit per posar en marxa aquest projecte: des de la selecció i adaptació del programari amb el que funciona (DSpace), fins als treballs duts a terme per establir les polítiques d'accés, d’introducció de dades, de metadades Dublin Core necessàries per descriure els documents, el tipus de llicència de les Creative Commons sota la qual es troben subjectes els documents, etc.

Anàlisi de l'estructura d'aprenentatge en l'ensenyament de l'educació fí­sica en l'educació obligatòria

En el present treball de recerca s'analitza l'estructura d'aprenentatge que els mestres utilitzen en diverses classes d'educació física en l'educació obligatòria. El treball s'organitza en dues parts, una primera part on s'explica què s'entén per educació física i estructura d'aprenentatge i on es relacionen els objectius generals de l'àrea amb els tipus d'estructura d'aprenentatge, individualista, competitiva o cooperativa, més adient per tal d'aconseguir-los. I una segona part on es dissenyen els instruments per a l'anàlisi de l'estructura i l'aprenentatge i s'utilitzen per l'observació de les classes de cinc mestres de cinc escoles diferents de la comarca d'Osona. En les conclusions del treball s'analitza la idoneïtat dels instruments analitzats i es constata la gran utilització de l'estructura d'aprenentatge competitiva en les classes observades.

Estudio del patrón muscular y ventilatorio en hipercapnia: análisis de la interacción entre los sistemas cardiovascular – respiratorio

Investigación producida a partir de una estancia en el Instituto de Investigación en Ingeniería de Aragón (IIIA) de la Universidad de Zaragoza. Una de las principales dificultades a las que se enfrenta el personal médico en las unidades de cuidado crítico es la selección de los modos ventilatorios y la configuración de los parámetros de ventilación adecuados. La mayoría de los ventiladores disponibles en el mercado tienen un gran número de modos ventilatorios, con muy buenas prestaciones pero difíciles de configurar si no se cuenta con herramientas que tengan en cuenta las características antropométricas, fisiológicas, farmacológicas o patológicas propias de cada caso clínico. Determinar cual es el mejor modo ventilatorio para cada caso en determinada fase de la enfermedad, constituye un paso definitivo en el tratamiento clínico, puesto que la configuración apropiada de los parámetros de ventilación puede reducir el tiempo de conexión al ventilador y facilitar así la recuperación del paciente. El análisis del patrón respiratorio (muscular y ventilatorio), objetivo principal del trabajo realizado, permite identificar los parámetros más sensibles al estímulo respiratorio. Se analiza, diseña e implementa técnicas que permitan conocer mejor la respuesta del sistema de control respiratorio ante estímulos y patologías ventilatorias, mediante el tratamiento de señales biomédicas y simulación algorítmica del sistema respiratorio en situaciones particulares.

The Catalan countries project (1931-1939)

In the evolution of Catalan nationalism, as much politician as cultural, the period of II Spanish Republic (1931-1939) was essential. The obtaining of the Statute of Autonomy (1931-1932) supposed the beginning of a stage of expansion in multiple aspects. One of them were the contacts with the Catalanists nuclei of the rest of the cultural space of Catalan language in which, at that time, it would begin to call Catalan Countries (Balearic Islands, Valencian Country, Andorra, Rosselló, to l'Alguer). On Those Collaborations between cultural organizations, political and particular parties Catalonia always will be the model to follow. The Increasing connections will be visualized on press, as well as on cultural celebrations, policy of parties and Constituent Courts. This evolution will be cut by the Franco victory in the Civil War in 1939.

Cooperative Transmission and Radio Resources Management for Wireless Networks

Report for the scientific sojourn at the Multimedia Communications Laboratory, University of Texas at Dallas, USA, from September to December 2005. The cooperative transmission has been analyzed taking a broadcast relay channel which assumes a scenario with one source and multiple destinations. Moreover, in order to improve the performance in terms of mutual information, it has been considered that for each destination there is another nearby terminal (called relay) which will help to improve the performance of the destination. This scheme combines different types of channels considered in the information theory, such as the relay channel, broadcast channel and interference channel (if the relays transmit information intended only to its associated destination). In this work, the author has studied the optimal way to encode the signals for the different users, known as capacity region (i.e. related to radio resources management ), of the broadcast relay channel.

Catalan Policies and Experiences on Cooperative Repositories

The Centre de Supercomputació de Catalunya (CESCA) together with the Consorci de Biblioteques Universitàries de Catalunya (CBUC) started in 1999 a cooperative repository, named TDR, to file in digital format the full-text of the read thesis at the universities of our country to spread them worldwide in open access preserving the intellectual copyright of the authors. This became operational in 2001 and today it is a service fully consolidated not only among the Catalan universities, but also used by other Spanish universities. Since then, there are four additional cooperative repositories which have been created: RECERCAT, for research papers; RACO, for scientific, cultural and erudite Catalan magazines; PADICAT, for archiving Catalan web sites; and MDC, for Catalan digital collections of pictures, maps, posters, old magazines... These five repositories have some common characteristics: they are open access, that is, they are accessible on the internet for free; they mostly comply with the Open Archive Initiative interoperability protocol for facilitating the efficient dissemination of content; and they have been built in a cooperative manner so that it is easy to adopt common procedures and to share the repository developing and managing costs, it permits more visibility of the indexed documents throughout the search engines, and a better provision for long-term preservation can be made. In this paper we present the common policy established for the Catalan cooperative repositories, we describe the five of them briefly, and we comment on the results obtained of our 6-year experience since the first one became operational.

Cooperative production and efficiency

We characterize the sharing rule for which a contribution mechanism achieves efficiency in a cooperative production setting when agents are heterogeneous. The sharing rule bears no resemblance to those considered by the previous literature. We also show for a large class of sharing rules that if Nash equilibrium yields efficient allocations, the production function displays constant returns to scale, a case in which cooperation in production is useless.

Cooperative vs. non-cooperative mechanisms in the EU decision making process

According to the account of the European Union (EU) decision making proposed in this paper, this is a bargaining process during which actors shift their policy positions with a view to reaching agreements on controversial issues.