Anàlisi i cerca de subgrafs més densos mitjançant Hadoop MapReduce

Treballs Finals de Grau d'Enginyeria Informàtica, Facultat de Matemàtiques, Universitat de Barcelona, Any: 2013, Director: Elitza ManevaEn aquest projecte de final de grau tractarem el tema del “BigData” i de les seves aplicacions. Concretament i amb el tema que ens dona per títol, veurem com resoldre el problema de trobar subgrafs densos dins d’un graf gran, amb un algorisme adaptat per a un framework especial anomenat MapReduce, que conjuntament amb Hadoop són eines que ens permeten treballar amb problemes de BigData de manera distribuïda més fàcil. També veurem l’anàlisi de resultats dels diferents entorns de proves amb els diferents grafs estudiats i finalment veurem en els annexos un estudi dels costos d’ús dels serveis d’Amazon Cloud i un petit manual de funcionament

On the optimization of bipartite secret sharing schemes

Optimizing the ratio between the maximum length of the shares and the length of the secret value in secret sharing schemes for general access structures is an extremely difficult and long-standing open problem. In this paper, we study it for bipartite access structures, in which the set of participants is divided in two parts, and all participants in each part play an equivalent role. We focus on the search of lower bounds by using a special class of polymatroids that is introduced here, the tripartite ones. We present a method based on linear programming to compute, for every given bipartite access structure, the best lower bound that can be obtained by this combinatorial method. In addition, we obtain some general lower bounds that improve the previously known ones, and we construct optimal secret sharing schemes for a family of bipartite access structures.Peer ReviewedPostprint (author's final draft

Relaciones entre oficinas y centros de aprendizaje: los espacios de transición, la dependencia arquitectónica y la capacidad de reconfiguración del aula

Se analizan las relaciones que se establecen entre los espacios de trabajo, oficinas, y los espacios destinados a la docencia, centros universitarios. El caso de estudio se centra en EINA Centro Universitario de Diseño y Arte de Barcelona y fija sus objetivos en dos aspectos, el exterior y el interior de las aulas. El modelo de zonificación de espacios de trabajo The Solution Worker (Greene & Meyerson 2011) plantea que el diseño de oficinas debe responder a los matices que se encuentran entre la interacción y la privacidad. Los espacios intermedios o “share” toman un peso relevante en la actualidad de la distribución de cualquier proyecto de planificación y diseño de una oficina

In-Silico Analysis of pH-Dependent Liquid-Liquid Phase Separation in Intrinsically Disordered Proteins

This work was funded by European Union's Horizon 2020 research and innovation programme under GA 952334 (PhasAGE). S.V. was supported by the Spanish Ministry of Science and Innovation (PID 2019-105017RB-I00) and by ICREA Academia 2020. C.P.-G. was supported by the Secretariat of Universities and Research of the Catalan Government and the European Social Fund (2021 FI_B 00087).Intrinsically disordered proteins (IDPs) are essential players in the assembly of biomolecular condensates during liquid-liquid phase separation (LLPS). Disordered regions (IDRs) are significantly exposed to the solvent and, therefore, highly influenced by fluctuations in the microenvironment. Extrinsic factors, such as pH, modify the solubility and disorder state of IDPs, which in turn may impact the formation of liquid condensates. However, little attention has been paid to how the solution pH influences LLPS, despite knowing that this process is context-dependent. Here, we have conducted a large-scale in-silico analysis of pH-dependent solubility and disorder in IDRs known to be involved in LLPS (LLPS-DRs). We found that LLPS-DRs present maximum solubility around physiological pH, where LLPS often occurs, and identified significant differences in solubility and disorder between proteins that can phase-separate by themselves or those that require a partner. We also analyzed the effect of mutations in the resulting solubility profiles of LLPS-DRs and discussed how, as a general trend, LLPS-DRs display physicochemical properties that permit their LLPS at physiologically relevant pHs

Metamodeling and Audio Signals Design Process, for the Encounter Between Sound and Changing Forms

The context of the following work arises from an exploratory interest around sound and forms, in order to be able to structure fictional architectural envelopes of an audio-reactive nature, whose materialization is achieved through digital visualization techniques, and generative software of art and design. This research implies an interdisciplinary development, between different categories of knowledge, through which unconventional processes are built, where sound is activated as an element that generates random values of information, and that have a direct impact on the configuration and changing behavior of the form and environment. Today, the boundaries that define creative territories are increasingly flexible and adaptive, which allows establishing knowledge networks that expand the ranges of action of design activities

Modelització de la biodiversitat d'espècies mitjançant la sèrie geomètrica

La sèrie geomètrica és un model molt utilitzat en estudis de diversitat d'espècies. L'objectiu principal d'aquest treball és el d'investigar i comparar diferents estimadors del paràmetre del model geomètric. Primer es fa una introducció de la biodiversitat, i es presenten les gràfiques més utilitzades per representar les dades. S'introdueixen, també, els models més populars en aquest camp. Seguidament, el treball se centra en el model geomètric, i es presenten sis estimadors diferents del paràmetre de la sèrie geomètrica. L'ús d'aquests estimadors s'il·lustra amb dades empíriques d'estudis ecològics. Posteriorment es presenta, en els casos possibles, un interval de confiança per aquests estimadors. Per últim, es realitzen simulacions de dades amb R amb la finalitat d'avaluar els estimadors en termes de biaix, variància i error quadràtic mig, i veure quins d ells ens ofereixen una millor estimació del paràmetre del model

Projecte d’Il·luminació d’una rotonda: smart, eficient i LED

Projecte de caire luminotècnic i energètic basat en la senyalització d’una rotonda ubicada a la Plana de Vic mitjançant un sistema d’autocontrol ‘Smart’, de manera eficient i enllumenat LED. De manera innovadora, s’ha dissenyat una solució de senyalització amb balises LED per aportar un plus extra i diferenciar-se de qualsevol projecte d’enllumenat exterior convencional. Amb referència a tot el que comporta aquest projecte, s’afegeix qualsevol estudi de caràcter tècnic com ara, anàlisis luminotècnic, energètic, estructural i ambiental

On the information ratio of non-perfect secret sharing schemes

The final publication is available at Springer via http://dx.doi.org/10.1007/s00453-016-0217-9A secret sharing scheme is non-perfect if some subsets of players that cannot recover the secret value have partial information about it. The information ratio of a secret sharing scheme is the ratio between the maximum length of the shares and the length of the secret. This work is dedicated to the search of bounds on the information ratio of non-perfect secret sharing schemes and the construction of efficient linear non-perfect secret sharing schemes. To this end, we extend the known connections between matroids, polymatroids and perfect secret sharing schemes to the non-perfect case. In order to study non-perfect secret sharing schemes in all generality, we describe their structure through their access function, a real function that measures the amount of information on the secret value that is obtained by each subset of players. We prove that there exists a secret sharing scheme for every access function. Uniform access functions, that is, access functions whose values depend only on the number of players, generalize the threshold access structures. The optimal information ratio of the uniform access functions with rational values has been determined by Yoshida, Fujiwara and Fossorier. By using the tools that are described in our work, we provide a much simpler proof of that result and we extend it to access functions with real values.Peer ReviewedPostprint (author's final draft

Seven ways of designing

On 18 and 19 November 2015 the Seven Ways of Designing intensification seminars took place. They were attended by third and fourth year students on the Degree in Design at EINA Centre for Art and Design which is attached to the Universitat Autònoma de Barcelona. The sessions focused on solving two problems: the lack of student autonomy in understanding their own working processes, as detected in their degree final projects, and a drop in motivation in third year students as a result of the overexposure to technical subjects in the curriculum. This article describes the seminars and analyses the attainment of the two objectives from a quantitative and qualitative viewpoint. As a result of the evaluation of the students’ processes during the seminars a certain polarisation in student autonomy was observed. The surveys show success in recovering motivation. Interviews with the participants show that learning the design process may be linked to the idea of “personal discovery”. In conclusion we stress the need to include this kind of seminar in every term in order to monitor student autonomy in different academic years and to maintain motivation

Linear threshold multisecret sharing schemes

In a multisecret sharing scheme, several secret values are distributed among a set of n users, and each secret may have a differ- ent associated access structure. We consider here unconditionally secure schemes with multithreshold access structures. Namely, for every subset P of k users there is a secret key that can only be computed when at least t of them put together their secret information. Coalitions with at most w users with less than t of them in P cannot obtain any information about the secret associated to P. The main parameters to optimize are the length of the shares and the amount of random bits that are needed to set up the distribution of shares, both in relation to the length of the secret. In this paper, we provide lower bounds on this parameters. Moreover, we present an optimal construction for t = 2 and k = 3, and a construction that is valid for all w, t, k and n. The models presented use linear algebraic techniques.Peer ReviewedPostprint (author’s final draft