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Understanding the long-term dynamics of forest transition: Fromdeforestation to afforestation in a Mediterranean landscape (Catalonia, 1868-2005)

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Cervera Zaragoza, Teresa, Pino i Vilalta, Joan, Marull López, Joan, Padró i Caminal, Roc, Tello, Enric

As other Mediterranean areas, Catalonia has experienced a forest transition following rural abandonmentduring the last sixty years. The GIS reconstruction of three land-use maps of 1868, 1956 and 2005 showshow forests have encroached former cropland and pasture land from the 1950s onwards, after a previouswave of deforestation. Forest inventories reveal the overpressure exerted on woodlands up to the 1950s,and their poor ecological status in terms of age structure, diversity and maturity. They…



Empresarios, militares y políticos. La Compañía Española de Minas del Rif (1907-1967) Reseña de Pablo DÍAZ MORLÁN (2015) Col. Marcial Pons Historia, Publicacions de la Universitat d'Alacant en Revista de Estudios Internacionales Mediterráneos [Ressenya de llibre]

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Mañé Estrada, Aurèlia

A lo largo de este libro Pablo Díaz Morlán nos relata el gran negocio que fue la Compañía Española de Minas del Rif (CEMR), la mayor empresa del protectorado de Marruecos. De hecho, el autor califica a la CEMR como una fuente de rentas imparable y sostiene que, para sus propietarios, embolsarse unos jugosísimos dividendos fue el único objetivo de su empresa. De hecho, este libro es la narración histórica y documentada de un "pelotazo" por expresarlo en términos vulgares, que dieron…



La electra Igualadina i el fènix del procés d'industrialització iguladí (1903-1930)

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Pascual i Domènech, Pere, 1945-

Aquest estudi tracta de la formació i trajectòria de L'Electra Igualadina (constituïda el 1903), una petita central termoelèctrica que va tenir un paper decisiu a la reindustrialització d'una ciutat industrial en crisi. La seva existència va comportar la proliferació de motors elèctrics, va determinar que la indústria local experimentes grans avanços en la seva mecanització i intensos augments de productivitat. Aquest procés va implicar que la ciutat pugues aprofitar l'…



Cambio institucional y sociedad esclavista: la intensificación del mercado de trabajo esclavo en Matanzas (Cuba), 1755-1810

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Urrego Mesa, J. Alexander

El análisis institucional de largo plazo ha fosilizado las transformaciones institucionales en Cuba creando la imagen de una sociedad esclavista para todo el periodo colonial. La historiografía sobre la esclavitud, aunque señala el proceso de cambio, no ha definido sus características y etapas. Este artículo busca comprender la formación de la sociedad esclavista cubana, situar históricamente las transformaciones hacia la economía de plantación en las últimas décadas del siglo xviii y describir…



PYMES no estatales socialistas: análisis para el caso cubano

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Palacios Cívico, Juan Carlos

El presente artículo se propone contribuir al debate respecto a la estructura de la propiedad de los medios de producción en una economía socialista como la cubana; mediante la formulación y análisis de dos cuestiones fundamentales: en primer lugar, evaluar si puede o no el desarrollo de las PYMES paliar parte de los problemas estructurales que afectan a la economía cubana en la actualidad. En cuyo caso, se haría necesario plantear y profundizar sobre las características que deberían presentar…



Land-use and rural inequality profiles in the province of Barcelona in mid-nineteenth century

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Tello, Enric, Badia-Miró, Marc

The long-term impact on income inequality of agricultural commercial specialization is still an open-ended discussion. Diverse economic models and approaches offer competing views, while historians increasingly stress the contingent nature of the paths followed in the various contexts. Applying common inequality indices like the Theil index along with new ones such as the inequality possible frontier (IPF) and Inequality Extraction Ratios (IER), this study examines how winegrowing…



Chilean trade 1880-1930: A comment on the sources for the Age of Exports

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Badia-Miró, Marc, Díaz-Bahamonde, José

This research note discusses the accuracy of the main sources used to study the foreign sector during the export-led growth process in Chile. Chilean foreign trade statistics are available for the period under analysis (1850-1930) and offered a good overview of products exported and imported. Bilateral trade data are also available providing information of exports and imports by origin and destiny. Although more research is needed on trade prices, we conclude that Chilean statistics are…



The inequality trap. A comparative analysis of social spending between 1880 and 1933 [WP]

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Espuelas Barroso, Sergio

[spa] Utilizando dos indicadores alternativos de redistribución –las transferencias sociales y el gasto social- durante el periodo de tiempo comprendido entre 1880 y 1933, y utilizando dos indicadores alternativos de desigualdad –el porcentaje de explotaciones agrarias no familiares y los top income shares-, este papel muestra que, al contrario de lo que muchos estudios sobre los origines del Estado del Bienestar suelen sugerir, la desigualdad no favoreció el desarrollo de la política social ni…, [eng] Using two alternative indicators of redistribution -social transfers and social spending- over the time-period 1880-1933 and using two alternative proxies for inequality -the percentage of non-family farms and the top income shares-, this paper shows that, contrary to what many studies on the origins of the welfare state appear to implicitly suggest, inequality did not favour the development of social policy even in its early stages. Since social policy developed more easily in countries…



Landscape Agroecology. The Dysfunctionalities of Industrial Agriculture and the Loss of the Circular Bioeconomy in the Barcelona Region, 1956-2009

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Cattaneo, Claudio, Marull López, Joan, Tello, Enric

The paper analyses how between 1956 and 2009 the agrarian metabolism of the Barcelona Metropolitan Region (BMR) has become less functional, losing circularity in biomass flows and in relationship to its landscape. We do so by adopting a Multi-Energy Return on Investment (EROI) and flow-fund (MuSIASEM) analyses and the nexus with landscape functional structure. The study of agricultural flows of Final Produce, Biomass Reused and External Inputs is integrated with that of land use, livestock,…



Consolidation and rationalization of the public companies in Spain: the information and communication technologies (ICT) holding

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Calvo Calvo, Ángel, 1949-

This article aims to study a strategic sector in the first years of the new millennium, whose results have been already been partially presented. It is structured into four main sections, which include the introduction, a presentation of the public sector of information and communication technologies, the restructuring of the public sector of ICTs and the birth of the Inisel group, called to play an important role in the future for its leading role in the creation of the technological firm…



Pastures and Cash Crops: Biomass Flows in the Socio-Metabolic Transition of Twentieth-Century Colombian Agriculture

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Urrego Mesa, J. Alexander, Infante Amate, Juan, Tello, Enric

This article aims to situate a national case study of the global periphery at the core of the debate on the socio-ecological transition by drawing on new data of biomass flows in twentieth-century Colombia. We draw up a century-long annual series converting a wide set of indicators from Net Primary Production (NPP) into the final socioeconomic uses of biomass, distinguishing around 200 different categories of crops, forests, and pastures. Our calculations draw on FAOSTAT and several corpuses of…



Francesc Valls Junyent (1966-2017). De la Mediterrània a l'Atlàntic

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Catalán, Jordi

L'obra de Francesc Valls revisita el llarg període de 1650 a 1990. ens ofereix les claus de com Catalunya, un exportador de derivats vitivinícoles com Portugal o el Llenguadoc, esdevingué protagonista de la revolució industrial a la Mediterrània. També ens ensenya com, després dels cicles de l'aiguardent i el vi de qualitat, el cava lliurà la batalla al xampany francès i com les terres de la Catalunya interior experimentaren un procés d'industrialització i desindustrialització…



Sampling of real multivariate polynomials and pluripotential theory

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Berman, Robert J., Ortega Cerdà, Joaquim

We consider the problem of stable sampling of multivariate real polynomials of large degree in a general framework where the polynomials are defined on an affine real algebraic variety $M$, equipped with a weighted measure. In particular, this framework contains the well-known setting of trigonometric polynomials (when $M$ is a torus equipped with its invariant measure), where the limit of large degree corresponds to a high frequency limit, as well as the classical setting of one-variable…



Asymptotically optimal designs on compact algebraic manifolds

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Etayo, Ujué, Marzo Sánchez, Jordi, Ortega Cerdà, Joaquim

We find $t$-designs on compact algebraic manifolds with a number of points comparable to the dimension of the space of polynomials of degree $t$ on the manifold. This generalizes results on the sphere by Bondarenko, Radchenko and Viazovska. Of special interest is the particular case of the Grassmannians where our results improve the bounds that had been proved previously.



Socioecological Transition in Land and Labour Exploitation in Mallorca: From Slavery to a Low-Wage Workforce, 1229-1576

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Jover i Avellà, Gabriel, Mas i Forners, Antoni, 1968-, Soto i Company, Ricard, 1954-, Tello, Enric

The permanence of slave labour until the 16th century was a lasting legacy of the late feudal colonization of the Mallorca Island. Through a large set of probate inventories and accounting books, we have documented the use of a great deal of slaves in farming large noble estates during the 14th and 15th centuries. The defeat of the peasant revolt of 1450-1454 offered to nobles and patricians the opportunity to seize much of the land previously colonized by Mallorcan peasants. This creation of a…



Sector privado y sector público en la industria española de alta tecnología: Indra

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Calvo Calvo, Ángel, 1949-

La investigación se centra en el análisis de los entresijos e implicaciones diversas que intervinieron en la creación y evolución de una empresa española de alta tecnología: Indra. El texto se estructura en cuatro grandes apartados principales, que responden a las etapas primordiales de Indra. El primero aborda el nacimiento, el segundo la reestructuración, reordenación y consolidación de la empresa entre 1993-1998 y el tercero el crecimiento posterior. Cierra la lista el relativo a la…



Expected Riesz Energy of Some Determinantal Processes on Flat Tori

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Marzo Sánchez, Jordi, Ortega Cerdà, Joaquim

We compute the expected Riesz energy of random points on flat tori drawn from certain translation invariant determinantal processes and de- termine the process in the family providing the optimal asymptotic expected Riesz energy.



Contractive inequalitie for Bergman spaces and multiplicative Hankel forms.

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Bayart, Frédéric, Brevig, Ole Fredrik, Haimi, Antti, Ortega Cerdà, Joaquim, Perfekt, Karl-Mikael

Abstract. We consider sharp inequalities for Bergman spaces of the unit disc, establishing analogues of the inequality in Carleman's proof of the isoperimet- ric inequality and of Weissler's inequality for dilations. By contractivity and a standard tensorization procedure, the unit disc inequalities yield correspond- ing inequalities for the Bergman spaces of Dirichlet series. We use these results to study weighted multiplicative Hankel forms associated with the Bergman spaces of…



Cooperation, Fair Trade, and the Development of Organic Coffee Growing in Chiapas (1980-2015)

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Folch, Albert, Planas i Maresma, Jordi, 1963-

In present day Mexico, Chiapas is the state that produces the greatest amount of coffee, with both the highest number of producers and the largest cultivated area. A significant part of this production is organic coffee. Organic coffee growing emerged as an important alternative for small producers who previously devoted themselves to the production and commercialization of conventional coffee but found it increasingly difficult to make a living. The expansion of the cultivation of organic…



Ramon Romaní i Puigdengolas (1846-1898): paperer, empresari i historiador

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Gutierrez i Poch, Miquel

Els plantejaments de Joseph A. Schumpeter situen l'empresari en el centre de l'activitat econòmica. Segons aquesta teoria, doncs, l'empresari era el principal impulsor del creixement. L'economista austríac distingia cinc tipus diferents d'innovació: innovació en els productes, innovació en els processos, obertura de nous mercats, noves fonts d'oferta de matèries primeres i béns semi manufacturats, i canvis organitzatius. ...



Geography, policy, or productivity? Regional trade in five South American countries, 1910-50

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Badia-Miró, Marc, Carreras Marín, Anna, Meissner, Christopher M.

Regional trade in South America since independence has long been much smaller than would be expected if geography were the only constraint on trade. Several potential explanations exist, including low technological and demand complementarities; low productivity; and high natural and policy barriers to trade. Focusing on the latter explanations, policy makers have long advocated a South American/Southern Cone Free Trade Area¿proposed as early as 1889. Would reductions in trade costs have been…



Desarrollo de competencias y docencia de conocimientos históricos en grados universitarios fuera del ámbito de la Historia

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Blasco, Yolanda, Ibarz Gelabert, Jordi, Lo Cascio, Paola, Monterde Mateo, Òscar, Maynou Felker, Marc

Las asignaturas que desarrollan conocimientos históricos han llegado a ser transversales en muchas titulaciones no específicamente históricas. El conocimiento del pasado permite desarrollar un conjunto de competencias en diversas titulaciones como Economía, Administración y Dirección de Empresas, Sociología, Ciencias Políticas... Esto ofrece nuevos retos a la docencia de contenidos históricos. En este caso queremos trabajar la experiencia con las asignaturas de historia dirigidas a tres grados…



El Manifest comunista en la història del pensament

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Argemí i d'Abadal, Lluís, 1945-2007

[spa] Este artículo reivindica la obra de Marx y Engels, en especial el Manifiesto comunista, como obra clásica imprescindible en las ciencias políticas y económicas y en sociología, por la influencia que ha dejado en la cultura occidental. A través del análisis de los aspectos formales, teóricos y políticos del Manifiesto comunista, Lluís Argemí nos hace tomar consciencia de las grandes aportaciones de Marx y Engels al pensamiento político y social actual y de hasta qué punto han determinado…, [cat] Aquest article reivindica l’obra de Marx i Engels, en especial el Manifest comunista, com a obra clàssica imprescindible en les ciències polítiques, econòmiques i en sociologia, per la influència que ha deixat en la cultura occidental. A través de l’anàlisi dels aspectes formals, teòrics i polítics del Manifest comunista, Lluís Argemí ens fa prendre consciència de les grans aportacions de Marx i Engels al pensament polític i social actual i de fins a quin punt ha determinat els paràmetres…, [eng] This article claims for the Marx and Engels’ writings, specially The Communist Manifest, as a contemporary classic indispensable to Political Science, Economics and Sociology for all its influence in Western culture. Throug the analysis of formal, theoretic and political aspects of The Communist Manifest, Lluís Argemí tries to make us conscientious of Marx and Engels’ great contribution to the political and social present thought.



Polarity analisys od reviews based on the omission of asymetric sentences

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Roberto, John, Salamó Llorente, Maria, Martí Antonin, M. Antònia

In this paper, we present a novel approach to polarity analysis of product reviews which detects and removes sentences with the opposite polarity to that of the entire document (asymmetric sentences) as a previous step to identify positive and negative reviews. We postulate that asymmetric sentences are morpho-syntactically more complex than symmetric ones (sentences with the same polarity to that of the entire document) and that it is possible to improve the detection of the polarity…



Cotton manufacturers as bankers: the textile trade and credit in spain, 1840-1913

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Prat Sabartés, Marc

[cat] La historiografia ha assenyalat que en el segle XIX el crèdit que els fabricants cotoners catalans oferien als seus clients era de caràcter informal i, per tant, impossible de ser transferit al sistema bancari. Això hauria tingut un efecte negatiu en la rendibilitat de les empreses cotoneres. A partir de l’anàlisi de diversos arxius empresarials, així com de fonts judicials i notarials, aquest treball confirma aquesta descripció dels fets però proposa una interpretació més optimista. Els…, [eng] Historians claim that in the nineteenth century Catalan cotton manufacturers were giving informal credit to their clients, and were therefore unable to transfer this credit to the banking system. Such circumstances would have had a detrimental effect on the profitability of the cotton firms. Based on an analysis of the archives of several firms, as well as judicial and notary sources, we can confirm this state of affairs, but present a more optimistic interpretation of the system.…



On the canonical ideal of one-dimensional Cohen-Macaulay local rings

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Elías García, Joan

In this paper we consider the problem of explicitly finding canonical ideals of one-dimensional Cohen-Macaulay local rings. We show that Gorenstein ideals contained in a high power of the maximal ideal are canonical ideals. In the codimension 2 case, from a Hilbert-Burch resolution, we show how to construct canonical ideals of curve singularities. Finally, we translate the problem of the analytic classification of curve singularities to the classification of local Artin Gorenstein rings with…



A multi-state model to estimate incidence of heroin use

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Sánchez Niubò, Albert, Aalen, Odd O., Domingo i Salvany, Antònia, Amundsen, Ellen J., Fortiana Gregori, Josep, Røysland, Kjetil

Background: Existing incidence estimates of heroin use are usually based on one information source. This study aims to incorporate more sources to estimate heroin use incidence trends in Spain between 1971 and 2005. Methods: A multi-state model was constructed, whereby the initial state "heroin consumer" is followed by transition to either "admitted to first treatment" or to "left heroin use" (i.e. permanent cessation or death). Heroin use incidence and…



Poncelet a la presó de Saratov

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Naranjo del Val, Juan Carlos

Poncelet va ser un militar francès que va formar part de les tropes napoleòniques que van perdre la batalla de Krasni a la campanya de Rússia. Durant el seu captiveri a la presó de Saratov, basant-se en el record de les lliçons inspiradores de Gaspard Monge a l'École Polytechnique, va reflexionar sobre els fonaments de la geometria projectiva i en va donar un punt de vista original que acabarà tenint una gran influència en el desenvolupament de la geometria al llarg del segle xix. Entre…



Introducción al semimonográfico: Desarrollo y cooperación internacional

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Gutiérrez-Goiria, Jorge, Maestro Yarza, Irene

Se publican en este número de la REC tres artículos relacionados con los debates actuales sobre el Desarrollo y la Cooperación Internacional, un tema objeto de controversias diversas y sobre el que el banico de enfoques y puntos de vista críticos es cada vez más amplio. (...)



Deborah Braütigam; Odd-Helge Fjeldstad and Mick Moore (eds.) Taxation and State Building in Developing Countries. Capacity and Consent. Cambridge University Press, Cambridge, 2008, 294 pp. [Ressenya de llibre]

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Peres Cajías, José Alejandro

Los impuestos son una obligación que no implica una contraparte inmediata, ni mucho menos proporcional, por parte del Estado. La recaudación impositiva requiere, entonces, de un acuerdo mínimo entre sociedad y Estado, donde se negocien -implícita o explícitamente- derechos y deberes. En la medida que ambas partes cumplan sus obligaciones, las probabilidades de alcanzar acuerdos más amplios es mayor. En el caso estatal, el potencial de cumplimiento de éstos se halla determinado por la cantidad…



Global-scale comparisons of human land use: developing shared terminology for land-use practices for global change

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Morrison, Kathleen D., Tello, Enric, Hammer, E., Popova, L., Madella, M., Whitehouse, N., Gaillard, M-J

Although archaeological data are needed to understand the impacts of past human land use on the Earth system, synthesis is hampered by a lack of consistent categories. We develop hierarchical and scalable land-use classifications for use across the globe.



Martín Rodrigo y Alharilla. La familia Gil. Empresarios catalanes en la Europa del siglo XIX, Madrid, Lid Editorial y Fundación de Gas Natural, 2010, 231 pp. [Ressenya de llibre]

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Blasco, Yolanda

En este libro se presenta el recorrido empresarial de dos generaciones de la familia Gil a lo largo del siglo XIX. En el análisis de su trayectoria empresarial se destacan dos aspectos: la forma en que la familia realizó la acumulación del capital original, que no fue distinta al habitual en la época (actividades comerciales, matrimonios ) y la forma en que insertaron su actividad empresarial en el periodo caracterizado por el despegue de la industrialización. (...)



Fatou components and singularities of meromorphic functions

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Baranski, Krzysztof, Fagella Rabionet, Núria, Jarque i Ribera, Xavier, Karpinska, Boguslawa

We prove several results concerning the relative position of points in the postsingular set $P(f)$ of a meromorphic map $f$ and the boundary of a Baker domain or the successive iterates of a wandering component. For Baker domains we answer a question of Mihaljevi\'c-Brandt and Rempe-Gillen. For wandering domains we show that if the iterates $U_n$ of such a domain have uniformly bounded diameter, then there exists a sequence of postsingular values $p_n$ such that $\dist(p_n, U_n)\to 0$ as $…



Análisis de la riqueza léxica en el contexto de la clasificación de atributos demográficos latentes

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Roberto, John, Martí Antonin, M. Antònia, Salamó Llorente, Maria

In this paper we analyse the utility of lexical richness measures for predicting latent user attributes from Spanish opinionated texts. Our aim is to know how useful could be lexical richness to predict user's gender, age and regional origin. To this end, we applied 32 lexical richness measures over 1911 previously labeled texts with demographic information. This approach has the advantage that it is domain-independent with modest computational cost.



Agglomeration and labour productivity in Spanish industry: a long-term analysis

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Martínez Galarraga, Julio, Paluzie, Elisenda, Pons Novell, Jordi, Tirado, Daniel A.

This paper analyzes the relationship between spatial density of economic activity and interregional differences in the productivity of industrial labour in Spain during the period 1860-1999. In the spirit of Ciccone and Hall (1996) and Ciccone (2002), we analyze the evolution of this relationship over the long term in Spain. Using data on the period 1860-1999 we show the existence of an agglomeration effect linking the density of economic activity with labour productivity in the industry. This…, Aquest article analitza la relació entre la concentració geogràfica de l'activitat econòmica i les diferències interregionals en la productivitat del treball industrial a Espanya durant el període 1860-1999. Seguint a Ciccone i Hall (2002) i Ciccone (2002), s¿analitza l¿evolució a llarg termini d'aquesta relació a Espanya. Utilitzant les dades del període 1860-1999, mostrem la existència d'un efecte d'aglomeració que connecta la densitat de l'activitat econòmica amb la…



A Gesture Recognition System for Detecting Behavioral Patterns of ADHD

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Bautista Martín, Miguel Ángel, Hernández-Vela, Antonio, Escalera Guerrero, Sergio, Igual Muñoz, Laura, Pujol Vila, Oriol, Moya, Josep, Violant, Verónica, Anguera Argilaga, María Teresa

We present an application of gesture recognition using an extension of dynamic time warping (DTW) to recognize behavioral patterns of attention deficit hyperactivity disorder (ADHD). We propose an extension of DTW using one-class classifiers in order to be able to encode the variability of a gesture category, and thus, perform an alignment between a gesture sample and a gesture class. We model the set of gesture samples of a certain gesture category using either Gaussian mixture models or an…



Sullivan minimal models of operad algebras

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Cirici, Joana, Roig, Agustí

We prove the existence of Sullivan minimal models of operad algebras for a quite wide family of operads in the category of complexes of vector spaces over a field of characteristic zero. Our construction is an adaptation of Sullivan's original step by step construction to the setting of operad algebras. The family of operads that we consider includes all operads concentrated in degree 0 as well as their minimal models. In particular, this gives Sullivan minimal models for algebras over Com…



Integración económica y localización industrial. Cataluña, la fábrica de España: ¿cuándo y por qué?

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Tirado, Daniel A., Paluzie, Elisenda, Pons Novell, Jordi

En este artículo se analizan los determinantes de la localización de la actividad industrial en España durante la segunda mitad del siglo XIX. El objetivo es estudiar la existencia de cambios en los factores explicativos de la localización, con el fin de identificar los efectos de la integración económica sobre la geografía industrial española. Para hacerlo, en primer lugar se analiza la literatura histórica existente. En segundo lugar, se describen las teorías que explican la localización de l…, - En aquest article s'analitzen els determinants de la localització de l'activitat industrial a Espanya durant la segona meitat del segle XIX. L'objectiu és estudiar l'existència de canvis en els factors explicatius de la localització, per tal d'identificar els efectes de la integració econòmica sobre la geografia industrial espanyola. Per fer-ho, en primer lloc s'analitza la literatura històrica existent. En segon lloc, es descriuen les teories que expliquen la…, - In this paper we analyse the determinants of the localisation of industrial activity in Spain during the second half of the XIX century. In particular, we try to determine possible changes in the importance of the factors that explain industrial location in order to study the effects of economic integration in Spain¿s industrial geography. To his aim, firstly we review the historical analysis of the changes experienced by Spain¿s industrial geography during this period. Secondly, we summarise…



Regional integration and specialisation patterns in Spain

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Paluzie, Elisenda, Pons Novell, Jordi, Tirado, Daniel A.

The aim of this paper is to analyse how economic integration in Europe has affected industrial geographical concentration in Spain and explain what the driving forces behind industry location are. Firstly, we construct regional specialisation and geographical concentration indices for Spanish 50 provinces and 30 industrial sectors in 1979, 1986 and 1992. Secondly, we carry out an econometric analysis of the determinants of geographical concentration of industries. Our main conclusion is that…, - L'objectiu d'aquest treball és analitzar com la integració econòmica a Europa ha afectat a la concentració geogràfica de les indústries a Espanya i explicar quines són les forces determinants de la localització industrial. En primer lloc, construïm índexs d'especialització regional i de concentració geogràfica per a les 50 províncies espanyoles i per 30 sectors industrials el 1979, 1986 i 1992. En segon lloc, realitzem una anàlisi economètrica dels determinants de la…



Foreign trade traps in the european periphery: Spain, 1870-1913

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Herranz Loncán, Alfonso, Tirado, Daniel A.

In this article we research into the difficulties that foreign trade imposed on Spanish process of integration into the international economy in the years prior to the First World War. We start out by examining some features of the foreign trade structure of the country. By means of an econometric analysis of import and export series, it is possible to observe the presence of a trend towards trade deficit, which was in force when Spain grew at a rate similar to that of its trading partners. We…, - En este artículo se estudian las dificultades que la balanza comercial creó al proceso de integración de España en la economía internacional en las décadas previas a la Primera Guerra Mundial. Se comienza analizando algunos de los rasgos estructurales del comercio exterior español. A través de un análisis econométrico de las series de importaciones y exportaciones puede observarse la presencia de una tendencia estructural hacia el déficit comercial, que actuaba cuando España crecía a tasas…



The geographical concentration of industry across Spanish Regions, 1856-1995

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Paluzie, Elisenda, Pons Novell, Jordi, Tirado, Daniel A.

New economic geography models show that there may be a strong relationship between economic integration and the geographical concentration of industries. Nevertheless, this relationship is neither unique nor stable, and may follow a ?-shaped pattern in the long term. The aim of the present paper is to analyze the evolution of the geographical concentration of manufacturing across Spanish regions during the period 1856-1995. We construct several geographical concentration indices for different…, Els models de la nova geografia econòmica mostren que pot existir una forta relació entre la integració econòmica i la concentració geogràfica de les indústries. Tot i així, aquesta relació no és ni unidireccional ni estable i pot seguir un patró en forma de Omega en el llarg termini. L'objectiu d'aquest article és analitzar l'evolució de la concentració geogràfica de la indústria en les regions espanyoles durant el període 1856-1995. Es construeixen diversos índexs de…



Vertical integration or specialisation: producing and commercialising cotton goods (1815-1913)

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Prat Sabartés, Marc

This article describes the ways in which cotton goods were commercialised during the nineteenth century and the first third of the twentieth. Several national cases are analysed: Britain, as the Workshop of the World; France, Germany, Switzerland and the US, as core economies; and Italy and Spain as countries on the European periphery. The main question that we address is why some cotton industries vertically integrated their production and commercialisation processes, but others did not. We…, Aquest article descriu com es comercialitzaven els teixits de cotó durant el segle XIX i el primer terç del XX. S'analitzen diversos casos nacionals: la Gran Bretanya, com a 'taller del món' que era; quatre economies centrals com França, Alemanya, Suïssa i els Estats Units; i dos països europeus perifèrics, Itàlia i Espanya. La principal pregunta que es planteja és per què algunes indústries cotoneres integraven verticalment la producció i la comercialització, i en canvis d'…



On the depth of blowup algebras of ideals with analytic deviation one

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Zarzuela, Santiago

Let I be an ideal in a local Cohen-Macaulay ring (A, m). Assume I to be generically a complete intersection of positive height. We compute the depth of the Rees algebra and the form ring of I when the analytic deviation of I equals one and its reduction number is also at most one. The formu- las we obtain coincide with the already known formulas for almost complete intersection ideals.



The free roots of the complete graph

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Casanovas Ruiz-Fornells, Enrique, Wagner, Frank O. (Frank Olaf), 1964-

There is a model-completion Tn of the theory of a (reflexive) ncoloured graph (X, R1,...,Rn) such that Rn is total, and Ri ◦ Rj ⊆ Ri+j for all i, j. For n > 2, the theory Tn is not simple, and does not have the strict order property. The theories Tn combine to yield a non-simple theory T∞ without the strict order property, which does not eliminate hyperimaginaries.



Articulated motion and deformable objects

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Wan, Jun, Escalera Guerrero, Sergio, Perales, Francisco J., Kittler, Josef

This guest editorial introduces the twenty two papers accepted for this Special Issue on Articulated Motion and Deformable Objects (AMDO). They are grouped into four main categories within the field of AMDO: human motion analysis (action/gesture), human pose estimation, deformable shape segmentation, and face analysis. For each of the four topics, a survey of the recent developments in the field is presented. The accepted papers are briefly introduced in the context of this survey. They…



On the Galois correspondence theorem in separable Hopf Galois theory

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Crespo Vicente, Teresa, Rio, Anna, Vela del Olmo, Ma. Montserrat

In this paper we present a reformulation of the Galois correspondence theorem of Hopf Galois theory in terms of groups carrying farther the description of Greither and Pareigis. We prove that the class of Hopf Galois extensions for which the Galois correspondence is bijective is larger than the class of almost classically Galois extensions but not equal to the whole class. We show as well that the image of the Galois correspondence does not determine the Hopf Galois structure.



Algebraic properties of the Lefschetz zeta function, periodic points and topological entropy

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Casasayas, Josefina, Llibre, Jaume, Nunes, Ana

The Lefschetz zeta function associated to a continuous self-map f of a compact manifold is a rational function P/Q. According to the parity of the degrees of the polinomials P and Q, we analize when the set of periodic points of f is infinite and when the topological entropy is positive.



Sampling measures

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Ortega Cerdà, Joaquim

We give a description of all measures such that for any function ia weighted Fock spaces the Lp norm with respect to the measure is equivalent to the usual norm in the space. We do so by a process of discretization that reduces the problem to the description of sampling sequences. The same kind of result holds for weighted Bergman spaces and the Paley-Wiener space.



Integrability: a difficult analytical problem

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Simó, Carles

Generically hamiltonian systems are non integrable o However there are few tools in order to prove that a given system is nonintegrableo For two degrees of freedom the usual methods rely upon the appearance of tran~ versal homoclinic or heteroclinic orbitso The transversal character is shown through evaluation of integrals along orbitso Such computation requl res the knowledgement of a one parameter family of periodic orbits and an explicit solution for the unperturbed (integrable) caseo Oue to…



Stability of parabolic points of area preserving analytic diffeomorphisms

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Simó, Carles

Theorems characterizing stable parabolic points are proved. Essentially, stability is equivalent to the fact that the generating function of the differomorphism, taking out the part which generates the identity, has a strict extremum at the fixed point. With these results, the study of the stability of fixed points of analytic area preserving mappings (APM) is ended . Some examples are included, specially the case of elliptic points whose ei-genvalues are cubic or fourth roots of unity.



Power-cancellation of CW-complexes with few cells

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Llerena, Irene

In this paper, we use the fact that the rings of integer matrices have the power-substitution property in order to obtain a powercancellation property for homotopy types of CW-complexes with one cell in dimensions 0 and 4n and a finite number of cells in dimension 2n.



Non-obstructed subcanonical space curves

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Miró-Roig, Rosa M. (Rosa Maria)

Recall that a closed subscheme X C P is non-obstructed if the corresponding point x of the Hilbert scheme Hilb'm is non-singular . A geometric characterization of non-obstructedness is not known even for smooth space curves . The goal of this work is to prove that subcanonical k-Buchsbaum, k _< 2, space curves are nonobstructed . As a main tool, we use Serre's correspondence between subcanonical curves and vector bundle



On the structure of the canonical module of the Rees algebra and the associated graded ring of and ideal

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Zarzuela, Santiago

In this note we give the description of a morphism related with the structure of the canonocal module of the Rees algebra R(I) of an ideal I in a local ring . As an application we obtain Ikeda's criteria for the Gorensteinness of R(I) and a result of IierzogSimis-Vasconcelos characterizing when the canonical module of R(I) has the expected form.



A note on Sugihara algebras

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Font Llovet, Josep Maria, Rodríguez Pérez, Gonzalo

In [41 Blok and Pigozzi prove syntactically that RM, the propositional calculus also called R-Mingle, is algebraizable, .and as a consequence there is a unique quasivariety (the so-called equivalent quasivariety semantics) associated to it . In [3] it is stated that this quasivariety is the variety of Sugihara algebras . Starting from this fact, in this paper we present an equational base for this variety obtained as a subvariety of the variety of R-algebras, found in [7] to be associated in…



Stratifications parfaites et théorie des poids

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Navarro, Vicenç (Navarro Aznar)

In this paper, we emphasize Deligne's theory of weights, in order to prove that some stratifications of algebraic varieties are perfect. In particular, we study in some detail the Bialynicki-Birula's stratifications and the stratifications considered by F. Kirwan to compute the cohomology of symplectic or geometric quotients. Finally we also appoint the motivic formulation of this approach, which contains the Hodge theoretic forrnulation.



Chaos expansions and local times

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Nualart, David, 1951-, Vives, Josep

In this note we prove that the Local Time at zero for a multipararnetric Wiener process belongs to the Sobolev space Dk- z-,,2 for any e > 0. We do this computing its Wiener chaos expansion We see also that this expansion converges almost surely . Finally, using the same teclrnique we prove similar results for a renormalized Local Time for the auto¡ ntersections of a planar Brownian motion.



Sobre àlgebres quasi-hilbertianes

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Pla i Carrera, Josep, Verdú, B. (Buenaventura)

In this paper we study the algebras obtained by having the deduction theorem on the sets of two elements, calling them Q.H. -algebras. Adding to them the FREGE'S law, we obtain a Hilbert algebra ; adding to them the law (x.y).y = (y.x).x, we obtain that thay form a variety; suposing the existence of a least element to the later , we obtain an ortolattice wich gives a boolean algebra on an ortomodular lattice, according to the nature of implication classical or strong



Interpolation of families Lμp

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Carro Rossell, María Jesús, Cerdà Martín, Joan Lluís

We identify the intermédiate space of a complex interpolation family - in the sense of Coifman, Cwikel, Rochberg, Sagher and Weissof LP spaces with change of measure, for the complex interpolation method associated to an analytic functional .



On the inverse problem of Galois theory

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Vila, Núria (Vila i Oliva)

The problem of the construction of number fields with Galois group over Q a given finite groups has made considerable progress in recent years. The aim of this paper is to survey the current state of this problem, giving the most significant methods developed in connection with it.



Una nota sobre la topología y el flujo en el problema restringido de tres cuerpos

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Benseny, Antoni

We study the topology of the unbounded region of the invariant manifolds with fixed values of the Jacobi constant C of the two-body problem, when C>3 . We describe the hamiltonian flow on this manifolds. TWo main consequences have been given : (i) a clarifyina result about the curves of zero velocity ; (ii) using the fact that the circular,planar and restricted three-body problem is a little perturbation of the two-body problem, when m or C-1 is sufficiently small, we prove the stability of…



El teorema de Fermat

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Bayer i Isant, Pilar, 1946-

Sus orígenes. El problema núunero 8 del Libro II de la Aritmética de Diofanto tiene el siguiente enunciado: 'Descomponer un cuadrado dado en dos cuadrados'. Si la respuesta a un problema no era única, Diofanto se limitaba a dar soluciones particulares, que obtenia gracias a una feliz elección de los datos. Veamos por ejemplo, cómo procede en el caso anterior. De entrada, se plantea resolver la ecuación...



On finite groups acting on acyclic complexes of dimension two

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Casacuberta, Carles, Dicks, Warren

We conjecture that every finite group C acting on a contractible CW-complex X of dimension 2 has at least one fixed point. We prove this in the case where Cis solvable, and under this additional hypothesis, the result holds for X acyclic.



Integration with respect to local time and Ito's formula for smooth nondegenerate martingales

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Bardina i Simorra, Xavier, Rovira Escofet, Carles

We show an It o's formula for nondegenerate Brownian martingales Xt = R t 0 us dWs and functions F(x, t) with locally integrable derivatives in t and x. We prove that one can express the additional term in It o's s formula as an integral over space and time with respect to local time.



Joining polynomial and exponential combinatorics for some entire maps

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Garijo Real, Antonio, Jarque i Ribera, Xavier, Moreno Rocha, Mónica

We consider families of entire transcendental maps given by Fλ,m(z) = λzm exp(z) where m ≥ 2. All these maps have a superattracting fixed point at z = 0 and a free critical point at z = −m. In parameter planes we focus on the capture zones, i.e., we consider λ values for which the free critical point belongs to the basin of attraction of z = 0. We explain the connection between the dynamics near zero and the dynamics near infinity at the boundary of the immediate basin of attraction of the…



Uniformization of triangle modular curves

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Bayer i Isant, Pilar, 1946-, Travesa i Grau, Artur

In the present article, we determine explicit uniformizations of modular curves attached to triangle Fuchsian groups with cusps. Their Hauptmoduln are obtained by integration of non-linear differential equations of the third order. Series expansions involving integral coefficients are calculated around the cusps as well as around the elliptic points. The method is an updated form of a differential construction of the elliptic modular function j, first performed by Dedekind in 1877. Subtle…



On the range space of Yano's extrapolation theorem and new extrapolation estimates at infinity.

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Carro Rossell, María Jesús

Given a sublinear operator T satisfying that !Tf!Lp(ν) ≤ C p−1 !f!Lp(µ), for every 1 < p ≤ p0, with C independent of f and p, it was proved in [C] that sup r>0 ! ∞ 1/r λν T f (y) dy 1 + log+ r ! ' M |f(x)|(1 + log+ |f(x)|) dµ(x). This estimate implies that T : L log L → B, where B is a rearrangement invariant space. The purpose of this note is to give several characterizations of the space B and study its associate space. This last information allows us to formulate an extrapolation…



Density estimates on a parabolic spde

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Márquez, David (Márquez Carreras), Mellouk, M.

We consider a general class of parabolic spde's ∂uε t,x ∂t = ∂2uε t,x ∂x2 + ∂ ∂x g(uε t,x) + f(uε t,x) + εσ(uε t,x)W˙ t,x, with (t, x) ∈ [0, T] × [0, 1] and εW˙ t,x, ε > 0, a perturbed Gaussian space-time white noise. For (t, x) ∈ (0, T] × (0, 1) we prove the called Davies and Varadhan-L´eandre estimates of the density pε t,x of the solution uε t,x.



The Fundamental Theorem of Algebra before Carl Friedrich Gauss

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Pla i Carrera, Josep

This is a paper about the first attempts of the demonstration of the fundamental theorem of algebra. Before, we analyze the tie between complex numbers and the number of roots of an equation of -n-th degree. In second paragraph we see the relation between the integration and fundamental theorern. Finally, we observe the linear differential equation with constant coefficients and the Euler's position about the fundamental theorem and then we consider the d'Alembert's, Euler's…



Division and extension in weighted Bergman-Sobolev spaces

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Ortega Aramburu, Joaquín M., Fàbrega Casamitjana, Joan

Let D be a bounded strictly pseudoconvex domain of Cn with C 8 boundary and Y = {z; u1(z) = ... = ul(z) = 0} a holomorphic submanifold in the neighbourhood of D', of codimension l and transversal to the boundary of D. In this work we give a decomposition formula f = u1f1 + ... + ulfl for functions f of the Bergman-Sobolev space vanishing on M = Y n D. Also we give necessary and sufficient conditions on a set of holomorphic functions {fa}|a|=m on M, so that there exists a holomorphic…



Un teorema de coincidencia

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Cerdà Martín, Joan Lluís

Si cp(t) = kt (0 5 k c 1), el teorema de la aplicación con tractiva asegura la existencia y unicidad de solución para



Àlgebres quasi-hilbertianes

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Pla i Carrera, Josep, Verdú, B. (Buenaventura)

In this paper we study the algebras obtained by having the deduction theorem on the sets of two elements, calling them Q.H.-algebras .Adding to them the FREGE'S law, we obtain a Hilbert algebra ; adding to them the law (x .y) .y = (y .x) .x, we obtain that thay form a variety; suposing the existence of a least element to the later , we obtain an ortolattice wich gives a boolean algebra on an ortomodular lattice, according to the nature of implication classical or strong.



Un recíproco de un teorema de A. Wilansky

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Canela Campos, Miguel Ángel

In this paper, we try to state a reciprocal of . a result of A. Wilansky : The dual of a Mazur space, provided with the topology of convergence on null sequences, is complete. Until now, we have proved this converse when the space is complete with respect to Mackey-convergence . To do this, we use a characterization of this type of completeness given by P. Dierolf.



Conditions of angelic type in function spaces

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Barceló, Miguel, Canela Campos, Miguel Ángel

This paper deals with a class of topological spaces in which α-compactness and compactness coincide and the tightness of a compact subset is less or equal than α, a being an infinite cardinal number. This class is a natural extension of the class of strictly angelic spaces, introduced by W . Govaerts . Sufficient conditions are given for a space of continuous functions to belong to this class, and some results on locally convex spaces are obtained as an application.



A primitivity criterion

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Nart, Enric, Vila, Núria (Vila i Oliva)

In this note we give a generalization of Furtwängler's primitivity criterion [E], in order to assure that a polynomial is primitive through his coefficients .



Cadenes de Sales discretes

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Torrens Torrell, Antoni

The Sales algebras are the substract of some positive implicational calculi . As a first aproximation to their representation we study the Sales algebras that are discrete and linear . In this paper we present a caracteritzation of the finite Sales algebras and we give also an infinite discrete Sales algebra such that we can identify with it every linear infinite simple Sales algebra with a penultimate element . The most interes ting result is the first Theorem In it we show that certain…



Anillos conmutativos cuyas extensiones enteras verifican la propiedad de 'going-between'

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Giral Silió, José Ma.

Let A and B denote commutative rings. We say that ACB satisfies going-between if iliven prime ideals...



Alguns aspectes actuals de lògica algebraica

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Pla i Carrera, Josep

L'any 1955 Paul R. HALMOS treu a 'Compositio Mathematicae, vol.12' l'article 'Algebraic Lògic' en el que dóna una formalització algebraica del concepte de deducció. A l'entorn dels anys seixanta l'escola d'Antonio NONTEIRO dóna una mateixa presentació algebraica però , en lloc de centrar la seva atenció en la lògica booleana, debilita la qüestió al substrat positiu de la lògica.



Formas cuadráticas sobre cuerpos totalmente p-ádicos

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Bayer i Isant, Pilar, 1946-

Dado un cuerpo de números K y un conjunto finito P de primos de K , se clasifican las formas cuadráticas sobre el cuerpo totalmente P-ádico Kp . El anillo de Witt W(Kp) resulta ser no finito . Su grupo aditivo es estudiado por medio del invariante de Clifford .



About some questions of differential algebra concerning to elementary functions

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Zarzuela, Santiago

The study of elementary functions, that is, of those functions built up by using rational functions over l, Exponentials, logarithms and algebraic operatons, began somewhat sistematically with the diverse works that Joseph Liouville did in the 1830's.



Caracteritzacions lògiques de certes àlgebres

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Verdú, B. (Buenaventura)

Lattices, distributive lattices, Hilbert algebras, relatively pseudo-complemented lattices and boolean algebras are structures which often arise in mathematical logic by means of some axioms and Tarski-Lindembaum quotients, or by some valuations and later identifications . In this paper we characterize these structures from a logical point of view, using conditions connecting the operacions with the consequence operator which defines the logic .



Cuasianaliticidad en espacios generales de funciones diferenciables

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Cufí, Julià, 1945-, Cerdà Martín, Joan Lluís

En (3) se ha introducido, para cada espacio de sucesiones lambda, una clase de funciones diferenciables, designada por E lambda (A), formada por las funciones f infinitamente diferenciables en A (subconjunto de Rn) tales que



La fundamentación del análisis de Fourier

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Cerdà Martín, Joan Lluís

El análisis de Fourier tiene que ver con cuestiones como las de representar funciones periódicas de variable real...



Notas sobre la difusión de Arnold

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Delshams, Amadeo

KAM theorem doesn't ensure stability for dynamical systems close to integrable Hamiltonian systems when the dimension of the phase space is more than four . In this case, irregular unstable orbits may occur, arbitrarily close to stable invariant tori . This is the Arnold diffusion . We study here some suf£icient conditions which guarantee the existence of this diffusion .



Una caracterización de las bornologías polares

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Canela Campos, Miguel Ángel

Let E be a regular b.c.s. ( a Hausdoff l.c.s. ), and let F be a normed space. We consider the spaces El all bounded ( continuous ) linear mappings of E into F, provided with its natural topology ( its equi continuous bornology ) . By defíning E^n= (E^n-1 )^1 for every n 1, we obtaín a sequence (E^n)n composed by, alternatively, b.c.s. and l.c.s.. We study the inclusion of E into E^2, giving a necessary and sufficient condition for a regular b.c.s. to be polar.



Some results in representable Banach spaces

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Canela Campos, Miguel Ángel

Some results are presented, concerning a class of Banach spaces introduced by G. Godefroy and M. Talagrand, the representable Banach spaces. The main aspects considered here are the stability in forming tensor products, and the topological properties of the weak* dual unitball.



Topologías sólidas en espacios normales de sucesiones

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Tort Pinilla, Manuel

Si E es un espacio normal de sucesiones, se considera el espacio Es de las formas lineales acotadas sobre las envolturas normales de los elementos de E . En este espacio se define un con cepto de conjunto normal que extiende el definido en el espacio...



Sobre extensiones centrales en una variedad de grupos [article]

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Llerena, Irene

El intento de generalizar los funtores de homología y de cohomologia, definidos en la categoría Gr de los grupos, a otras categorías, data ya de los años sesenta, con definiciones más o menos sofisticadas . Sin embargo, no es hasta 1970 cuando U . Stammbach da en (14) una definición de los funtores V y 9 como generalización de H2 y H2 , respectivamente, para el caso concreto de variedades de grupos . La mayor parte de las propiedades de H2 y H2 se generalizan sin dificultad a V y 9 , incluyendo…



Una contribución al análisis de proximidades

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Cuadras, C. M. (Carlos María), Ruiz-Rivas, Carmen

Una contribución al análisis de proximidades



Nota sobre el significado lógico de ciertas estructuras residuadas elementales

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Font Llovet, Josep Maria, Rodriguez Salas, A. J.

Starting from an abelian grupoid which is ordered and residuated we study the logical significance of the 'residue' operation, specially if we add the most natural algebraic properties to the base structure, obtaining then several well-Known structures of mathematical logic, such as the deductively-complete algebras and the algebras of Sales,Hilbert,Abbott,Wajsberg and Boole .We also give some properties of the deductive systems and obtain an special version of the deduction theorem…



Introducció d'interiors d'ordre en lògiques abstractes

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Font Llovet, Josep Maria

Let L = (S,C) be an abstract logic ( El]) . Using the methods of 131 we study the abstract logic . Lo = (S,C0) agsociated with 11,=1X C- S :X=C(X), f (XXX } for a given mapping f: S > S . We see that Lo preserves several logical properties of L . We state necessary and sufficient conditions on C to obtain separately the three properties of an interior mapping on the logical quotient of S by C, when the last is an ordered set, a semilattice, or an implicative algebra.



Sobre el teorema d'irreductibilitat de Hilbert

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Vila, Núria (Vila i Oliva)

Aquesta nota té per objectiu presentar una demostració simplificada del teorema d'iIreductibilitat de Hilben.



A theorem on Schauder decompositions of Banach spaces

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Ariño Martín, Miguel Ángel

In this paper we prove that in a Banach space all Schauder decompositions are slirinking iff all Schauder decompositions are boundedly complete.



On a certain type of primitive representations of rational integers as sum of squares

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Arenas, A. (Àngela), 1955-

It is well known that a positive integer not of the form 4a (8m+7) can be expressed as a sum of there integer squares . Dirichlet (cf . [1]) proved that a positive integer admits a primitive representation as a sum of there squares if and only if it is not of the form 8m+7 or 4m .



The concept of k-level for positive integers

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Arenas, A. (Àngela), 1955-

It is said (cf . [4]) that a positive integer n satisfies property (N) if there exists a representation of n as a sum of 3 squares, n = x1+x2+x3 , with (x 1 ,n) = 1 and x~ < n31 . It has been checked that every positive integer n < 600000, n - 3(mod 8), verifies property (N) .



Sobre l'axiomàtica no-standar de J. Keisler

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Pla i Carrera, Josep

This work deals wíth the axiomatic system of KEISLER on the hyperreals numbers .The main result ís to prove that the expressíons S of type



Algunas álgebras de funciones diferenciables

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Cerdà Martín, Joan Lluís, Cufí, Julià, 1945-

Si I es un intervalo, acotado o no, y si X es un espacio normal de sucesiones de números complejos que contiene a cp (espacio de las sucesiones casi nulas), como en [1] vamos a considerar el espacio ~a (I) de funciones f : I .-, de clase C °° tales que



Fatou components and singularities of meromorphic functions

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Baranski, Krzysztof, Karpinska, Boguslawa, Fagella Rabionet, Núria, Jarque i Ribera, Xavier

We prove several results concerning the relative position of points in the postsingular set P(f) of a meromorphic map f and the boundary of a Baker domain or the successive iterates of a wandering component. For Baker domains we answer a question of Mihaljević-Brandt and Rempe-Gillen. For wandering domains we show that if the iterates $U_{n}$ We prove several results concerning the relative position of points in the postsingular set P(f) of a meromorphic map f and the boundary of a Baker domain…



Bifurcation gaps in asymmetric and high-dimensional hypercycles

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Puig, Júlia, Farré, Gerard, Guillamon, Antoni, Fontich, Ernest, 1955-, Sardanyés, Josep

Hypercycles are catalytic systems with cyclic architecture. These systems have been suggested to play a key role in the maintenance and increase of information in prebiotic replicators. It is known that for a large enough number of hypercycle species (n>4) the coexistence of all hypercycle members is governed by a stable periodic orbit. Previous research has characterized saddle-node (s-n) bifurcations involving abrupt transitions from stable hypercycles to extinction of all hypercycle…



Definibilitat en estructures matemàtiques

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
Casanovas Ruiz-Fornells, Enrique

Discutim la noció de definibilitat de relacions, funcions i elements d'una estructura matemàtica mitjançant el llenguatge formal de la lògica de primer ordre en el context de la teoria de models. A través de l'exposició d'una sèrie d'exemples de problemes de definibilitat basats en sistemes numèrics familiars per a tot matemàtic, mostrem que l'anàlisi de la complexitat de les relacions definibles en una estructura aporta informació valuosa sobre qüestions de…



Sobre Corbes paramètriques i polígons de Newton

Repositorio: Recercat: Dipósit de la Recerca de Catalunya
D'Andrea, Carlos, 1973-, Sombra, Martín

Les corbes i superfícies algebraiques poden ser definides implícitament com a solucions d'equacions polinomials i, de vegades, també poden definir-se paramètricament, mitjançant funcions racionals. Plantegem el problema de la conversió d'una d'aquestes formes de representació a l'altra. A continuació, explorem la possibilitat d'obtenir, a partir de les equacions paramètriques i sense necessitat d'efectuar l'operació costosa de la implicitació, un objecte…