Iterated local search

Iterated Local Search has many of the desirable features of a metaheuristic: it is simple, easy to implement, robust, and highly effective. The essential idea of Iterated Local Search lies in focusing the search not on the full space of solutions but on a smaller subspace defined by the solutions that are locally optimal for a given optimization engine. The success of Iterated Local Search lies in the biased sampling of this set of local optima. How effective this approach turns out to be depends mainly on the choice of the local search, the perturbations, and the acceptance criterion. So far, in spite of its conceptual simplicity, it has lead to a number of state-of-the-art results without the use of too much problem-specific knowledge. But with further work so that the different modules are well adapted to the problem at hand, Iterated Local Search can often become a competitive or even state of the artalgorithm. The purpose of this review is both to give a detailed description of this metaheuristic and to show where it stands in terms of performance.

Monetary policy and exchange rate volatility in a small open economy

We lay out a small open economy version of the Calvo sticky price model, and show how the equilibrium dynamics can be reduced to simple representation in domestic inflation and the output gap. We use the resulting framework to analyze the macroeconomic implications of three alternative rule-based policy regimes for the small open economy: domestic inflation and CPI-based Taylor rules, and an exchange rate peg. We show that a key difference amongthese regimes lies in the relative amount of exchange rate volatility that they entail. We also discuss a special case for which domestic inflation targeting constitutes the optimal policy, and where a simple second order approximation to the utility of the representative consumer can be derived and used to evaluate the welfare losses associated with the suboptimal rules.

Nuclear incompressibility in the quasilocal density functional theory

We explore the ability of the recently established quasilocal density functional theory for describing the isoscalar giant monopole resonance. Within this theory we use the scaling approach and perform constrained calculations for obtaining the cubic and inverse energy weighted moments (sum rules) of the RPA strength. The meaning of the sum rule approach in this case is discussed. Numerical calculations are carried out using Gogny forces and an excellent agreement is found with HF+RPA results previously reported in literature. The nuclear matter compression modulus predicted in our model lies in the range 210230 MeV which agrees with earlier findings. The information provided by the sum rule approach in the case of nuclei near the neutron drip line is also discussed.

Scaling calculation of isoscalar giant resonances in relativistic Thomas-Fermi theory

We derive analytical expressions for the excitation energy of the isoscalar giant monopole and quadrupole resonances in finite nuclei, by using the scaling method and the extended ThomasFermi approach to relativistic mean-field theory. We study the ability of several nonlinear σω parameter sets of common use in reproducing the experimental data. For monopole oscillations the calculations agree better with experiment when the nuclear matter incompressibility of the relativistic interaction lies in the range 220260 MeV. The breathing-mode energies of the scaling method compare satisfactorily with those obtained in relativistic RPA and time-dependent mean-field calculations. For quadrupole oscillations, all the analyzed nonlinear parameter sets reproduce the empirical trends reasonably well.

General method to determine replica symmetry breaking transitions

We introduce a new parameter to investigate replica symmetry breaking transitions using finite-size scaling methods. Based on exact equalities initially derived by F. Guerra this parameter is a direct check of the self-averaging character of the spin-glass order parameter. This new parameter can be used to study models with time reversal symmetry but its greatest interest lies in models where this symmetry is absent. We apply the method to long-range and short-range Ising spin-glasses with and without a magnetic field as well as short-range multispin interaction spin-glasses.

El poblament vegetal de les valls de Barravés i Castanesa. I. Flora i vegetació

The study area lies in the central Pyrenees and corresponds to the basins of two adjacent rivers,Noguera Ribagorçana and Valira de Castanesa. Theyflow from North to South, and meet near El Pont deSuert. The area stretches from this point (875 m a. s. l.) to more than 3000 m, at the North summits bordering it.

Modelos itálicos y artesanado provincial: las lastras Campana de Tarraco y su territorio

In 1991 was brought to light a collection of architectural terracottas from the villa of the Vilarenc and some pieces from Tarraco that were identified as lastre Campana. Five years later, in the excavations of the Plaza de la Font of Tarragona, a collection of six pieces was discovered. Altogether, the collection is based in 14/15 lastre and 4 different topics: “Women flanking a candelabra”, “Theseus known by his father”, “Adornment of a hermes” and “Scene of portico of palestra”. The interest of these finds lies in several factors: Their absolute exceptionality (it is very rare to find them outside of Italy); the geographical concentration, the topics, and their chronological relation and precise culture, since the finds are concentrated in a provincial capital and its territory, and they come from contexts of the beginning of first century AD. The physicochimique analyses make possible to assign an origin from Latium to some pieces and a local manufacture to others. These finds make possible to talk about the area and the provincial impact of certain iconographic and cultural models of Augustus’ time.

La producción tarraconense de lastras Campana

En 1991 vió la luz una colección de terracotas arquitectónicas procedentes de la villa romana de El Vilarenc y otras pocas de Tárraco, que fueron identificadas como lastras Campana. Cinco años más tarde en las excavaciones de la Plaça de la Font de Tarragona fueron descubiertos seis nuevos ejemplares. Ahora, el conjunto consta de 14/15 piezas distribuidas en cuatro motivos iconográficos: “Mujeres flanqueando un candelabro”, “Teseo reconocido por su padre”, “Engalanamiento de un hermes” y “Escena de pórtico de palestra”. El interés radica en los siguientes factores: su absoluta excepcionalidad (son extremadamente raras fuera de Italia); su concentración geográfica en la capital y su territorio; y su precisa adscripción cronológica y cultural. Los análisis arqueométricos adjudican un orígen lacial para una y una fabricación local para las restantes. Este hecho permite plantear el tema de la adopción de modelos iconográficos de la capital –Roma– en la Tárraco post-augustea.

A web ontologies framework for digital rights management

In order to improve the management of copyright in the Internet, known as Digital Rights Management, there is the need for a shared language for copyright representation. Current approaches are based on purely syntactic solutions, i.e. a grammar that defines a rights expression language. These languages are difficult to put into practise due to the lack of explicit semantics that facilitate its implementation. Moreover, they are simple from the legal point of view because they are intended just to model the usage licenses granted by content providers to end-users. Thus, they ignore the copyright framework that lies behind and the whole value chain from creators to end-users. Our proposal is to use a semantic approach based on semantic web ontologies. We detail the development of a copyright ontology in order to put this approach into practice. It models the copyright core concepts for creation, rights and the basic kinds of actions that operate on content. Altogether, it allows building a copyright framework for the complete value chain. The set of actions operating on content are our smaller building blocks in order to cope with the complexity of copyright value chains and statements and, at the same time, guarantee a high level of interoperability and evolvability. The resulting copyright modelling framework is flexible and complete enough to model many copyright scenarios, not just those related to the economic exploitation of content. The ontology also includes moral rights, so it is possible to model this kind of situations as it is shown in the included example model for a withdrawal scenario. Finally, the ontology design and the selection of tools result in a straightforward implementation. Description Logic reasoners are used for license checking and retrieval. Rights are modelled as classes of actions, action patterns are modelled also as classes and the same is done for concrete actions. Then, to check if some right or license grants an action is reduced to check for class subsumption, which is a direct functionality of these reasoners.

Volcanoes of l-isogenies of elliptic curves over finite fields: the case l=3

This paper is devoted to the study of the volcanoes of l-isogenies of elliptic curves over a finite field, focusing on their height as well as on the location of curves across its different levels. The core of the paper lies on the relationship between the l-Sylow subgroup of an elliptic curve and the level of the volcano where it is placed. The particular case l = 3 is studied in detail, giving an algorithm to determine the volcano of 3-isogenies of a given elliptic curve. Experimental results are also provided.

Espigueo por la toponimia mayor del Valle Medio e Inferior del Ésera (Huesca)

El present treball pretén donar llum a una sèrie de topònims majors de la Ribagorça occidental, tot al llarg de la vall mitjana i inferior del riu Éssera. Aquests topònims es remunten a temps molt antics: preromans, romans i germànics bàsicament. Aquesta anàlisi permet apreciar l'estratigrafi a lingüística de la zona. La no-aparició de topònims d'origen àrab en el nostre treball no vol dir que no hi hagués penetració àrab a la zona, sinó que la seva arribada va ser posterior a la creació dels principals nuclis de població. Sí que hi ha topònims àrabs a la toponímia menor, que resta fora del present treball.

The role of fibroblast growth factor (FGF) and type beta transforming growth factot beta (TGF beta1, beta2 and beta3) during rat craniofacial development

Growth factors seem to be part of a complex cellular signalling language, in which individual growth factors are the equivalents of the letters that compose words. According to this analogy, informational content lies, not in an individual growth factor, but in the entire set of growth factors and others signals to which a cell is exposed. The ways in which growth factors exert their combinatorial effects are becoming clearer as the molecular mechanisms of growth factors actions are being investigated. A number of related extracellular signalling molecules that play widespread roles in regulating development in both invertebrates and vertebrates constitute the Fibroblast Growth Factor (FGF) and type beta Transforming Growth Factor ((TGF beta). The latest research literature about the role and fate of these Growth factors and their influence in the craniofacial bone growth ad development is reviewed

The role of fibroblast growth factor (FGF) and type beta transforming growth factot beta (TGF beta1, beta2 and beta3) during rat craniofacial development

Growth factors seem to be part of a complex cellular signalling language, in which individual growth factors are the equivalents of the letters that compose words. According to this analogy, informational content lies, not in an individual growth factor, but in the entire set of growth factors and others signals to which a cell is exposed. The ways in which growth factors exert their combinatorial effects are becoming clearer as the molecular mechanisms of growth factors actions are being investigated. A number of related extracellular signalling molecules that play widespread roles in regulating development in both invertebrates and vertebrates constitute the Fibroblast Growth Factor (FGF) and type beta Transforming Growth Factor ((TGF beta). The latest research literature about the role and fate of these Growth factors and their influence in the craniofacial bone growth ad development is reviewed

Combinationes novae

Ranunculus Balbisii Moris subsp. Weyleri (Mares et Vig.) comb, nova ( = Ranunculus Weyleri Mares et Vigineix, Catalogue raisonne des plantes vasculaires des lies Baleares : 5, Paris 1880).

Aportació al coneixement de l"herbari Trèmols de l"Institut Botànic de Barcelona.

The herbarium BC-Trèmols was created during the second half of the 19th century by the Catalan chemist and botanist Frederic Trèmols Borrell. Between 1930 and 1960, the technician Antoni Marcos carried out a thorough review. The current collection consists of approximately 9000 specimen sheets; is made up of 58 volumes reordered by Marcos,two volumes with the original structure, four boxes of Hieracium and 85 boxes with additional material. Up to now 22 volumes and four boxes of Hieracium have been computerized (3695 specimens); we made an inventory at genus level of all volumes, and we computerized the original catalogue of the herbarium and the existing taxonomical fiches. We have also developed a preliminary inventory of the contents of the extra boxes. The analysis of these 3695 herbarium specimens clearly shows that it mainly consists of samples obtained by exchange (67.1%) especially within the Société Helvétique pour l"Échange des Plantes and the Societat Botànica Barcelonesa. Among the materials studied we found two specimens regarded as interesting from a taxonomical and/or nomenclatural point of view (isotypes of Silene holzmanii Heldr. ex Boiss. and of Arenaria minutiflora Loscos). Therefore, the main interest of the herbarium lies in the diversity of the geographical provenance of plants, which makes of this collection one of the first"pan-European herbaria" in Catalonia.