Distributed LQG control of a water delivery canal with feedforward from measured consumptions

This work addresses the design of distributed LQG controllers for water delivery canals that include feedforward from local farmer water consumptions. The proposed architecture consists of a network of local control agents, each connected to one of the canal pools and sharing information with their neighbors in order to act in a coordinated way. In order to improve performance, the measurement of the outflows from each pool is used as a feedforward signal. Although the feedforward action is local. It propagates due to the coordinates procedure. The paper presents the distributed LQG algorithm with feedforward and experimental results in a large scale pilot water delivery canal

A sacred landscape: an enquiry of the “Cubas” from the South of Portugal

Ponencia presentada a Session 9: Forma urbana y relaciones entre historia y proyecto: el medio ambiente como patrimonio / Urban form and relationships between design and history: environmental heritage, arquitecture and planningThe purpose of this paper is to study the cubas – small constructions known for their domes painted with whitewash – specifically those located in the “kûra” of Beja in Portugal. Although we can pinpoint the existence of many of these buildings in the Beja territorial area, many questions remain about them, such as: What was the purpose of the cubas? When were they built? What is their origin? In order to try and answer these questions, I will be following two methods of analysis. First, I will focus on the correlation that exists between these buildings and the landscape in which they are located. This can shed some light on the reason behind their construction and the purpose of this type of structures. Secondly, I will analyse the buildings themselves – with special attention given to the metric and constructive analysis – in order to clarify the period of construction and the origin of their architectural typology. With this project I also aim to raise awareness of both the academic community and the political decision-makers on the existence of these buildings and their importance for the understanding of Iberian-Islamic culture. And maybe this can eventually inspire political action that will lead to the forging of policies for the preservation of this important part of our architectural and cultural heritage

Heritage Building Stones from Évora, Portugal

The city of Évora, a World Heritage Site recognized by UNESCO in 1986, also owes this recognition to the stones that built its monuments and preserve them until today. This work brings together the contributions that we have gathered over the past three decades and allow us to have a very complete idea, not only about the materials used in the hundreds of monuments and historic buildings but also about their provenance. If some materials are so emblematic that they allow an immediate identification with the naked eye, others needed more sophisticated and precise techniques so that there was no doubt about their origin. The igneous rocks and gneisses of granite composition are part of the “Massif of Évora” on which the city is built. Thus, and quite naturally they are by far the most represented group in monuments from all historical periods. Its function is essentially structural, but there are also functional, ornamental and decorative objects. For example, the oldest megalithic structures found in the vicinity of the city are made up of large granite blocks that often had to be transported to their locations. On the other hand, many gargoyles and statues that decorate the churches are also made up of these granite rocks. On these, the natural erosion of centuries of exposure to the environment has led to a state of alteration, sometimes very accentuated, which would justify its replacement by replicas sculpted in similar rocks. Provenance studies have made it possible to identify old quarries in the vicinity of the city where, on the one hand, the ancient rock extraction techniques can be observed and on the other hand, they allow the obtaining of the raw material necessary for these restoration and conservation works. In any case, they are places that need to be inventoried and protected, with the municipality already aware of their existence. As well as the monuments of the Roman Period, also the structures of the Medieval Period, such as the city walls, the Cathedral (started to be built in 1186 AD) and all the great churches, were also built with these granitoids. In addition to these rocks, many others of multiple varieties and origins are present. The marbles, especially the Estremoz Marbles (Global Heritage Stone Resource), are ubiquitous in the city, but there are also emblematic marbles from other places, some easily identifiable (ie Viana do Alentejo, Escoural, Trigaches, Serpa and Vila Verde de Ficalho, for presenting mineralogy, textures, colors and patterns which, together with more recent analytical techniques, have confirmed its provenance. Sedimentary rocks, with emphasis on Portuguese Mesozoic limestones, ie Lioz - GHSR and Brecha da Arrábida - GHSR candidate, among others more rare and with very specific use in ornamental details, are also present and contribute to enrich a heritage in stone that makes this city so special and very popular with tourists of all nationalities. Acknowledgments: the authors thank to FCT for funding the ICT (UID/GEO/04683/2019), as well as COMPETE POCI-01-0145-FEDER-007690

The Geology as an indispensable tool for optimizing the exploration of dimension Stones

Like any Geological Resource, the Dimension Stones can only be exploited where they occur. How they occur is a reflection of geological history that presided over its formation. Their nature determines the mode of deposit and therefore it’s potential to be exploited as ornamental stone. The geological setting of the Portuguese marbles became a key factor in the optimization of its exploitation, two ductile deformation phases must be consider, which originates the complex folded metamorphic layering. At least three fracturing systems are responsible for the high segmentation of the marbles in fragile deformation conditions and that must also be considered. Together these geological constraints lead to a really low production ratio (3% - 12%). These low efficiency productions emphasized the emergence of the geological knowledge of individual quarries in order to optimize is exploitation. Until recent years, with high prices for the Portuguese marbles the companies haven’t been concerned with the geological knowledge of its quarries, but now that an economic crisis is installed in the sector, basic geological studies in the quarries are mandatory and could save thousands of euros for each company

FastM: Design and Evaluation of a Fast Mobility Mechanism for Wireless Mesh Networks

Although there is a large volume of work in the literature in terms of mobility approaches for Wireless Mesh Networks, usually these approaches introduce high latency in the handover process and do not support realtime services and applications. Moreover, mobility is decoupled from routing, which leads to inefficiency to both mobility and routing approaches with respect to mobility. In this paper we present a new extension to proactive routing protocols using a fast mobility extension, FastM, with the purpose of increasing handover performance in Wireless Mesh Networks. With this new extension, a new concept is created to integrate information between neighbor wireless mesh routers, managing locations of clients associated to wireless mesh routers in a certain neighborhood, and avoiding packet loss during handover. The proposed mobility approach is able to optimize the handover process without imposing any modifications to the current IEE 802.11 MAC protocol and use unmodified clients. Results show the improved efficiency of the proposed scheme: metrics such as disconnection time, throughput, packet loss and control overhead are largely improved when compared to previous approaches. Moreover, these conclusions apply to mobility scenarios, although mobility decreases the performance of the handover approach, as expected

The average singular value of a complex random matrix decreases with dimension

We obtain a recurrence relation in $d$ for the average singular value $\alpha (d)$ of a complex valued $d\times d$\ matrix $\frac{1}{\sqrt{d}}X$ with random i.i.d., N( 0,1) entries, and use it to show that $\alpha (d)$ decreases monotonically with $d$ to the limit given by the Marchenko-Pastur distribution.\ The monotonicity of $\alpha (d)$ has been recently conjectured by Bandeira, Kennedy and Singer in their study of the Little Grothendieck problem over the unitary group $\mathcal{U}_{d}$ \cite{BKS}, a combinatorial optimization problem. The result implies sharp global estimates for $\alpha (d)$, new bounds for the expected minimum and maximum singular values, and a lower bound for the ratio of the expected maximum and the expected minimum singular value. The proof is based on a connection with the theory of Tur\'{a}n determinants of orthogonal polynomials. We also discuss some applications to the problem that originally motivated the conjecture.Comment: 11 page

Portuguese Secondary Schools: Places of Education and Networks of Complicity.Alentejo Elites’ Progress through School and Professional Career,Development 1841–1960

The aim of this paper is the relation between the local elites and the secondary level scool in Alentejo during the 19 th and 20 th centuries. These historiographical tendencies show very cleary the necessity of analysing the problem of the elites formal education under the view of the education’s social dimension, trying to evaluate the impacte of schooling’s trajectories in the social and economical dynamics. So, it will be in this perspective that i’ll support the empirical results, wich will be introduced. I will argue the secondary scools is a privilileged space of elites training and in which I establish the relative adptation of the teaching offered to the different kinds of professional and social perfomances that were demanded to the studentes who finished the secondary education