Line search multilevel optimization as computational methods for dense optical flow

We evaluate the performance of different optimization techniques developed in the context of optical flowcomputation with different variational models. In particular, based on truncated Newton methods (TN) that have been an effective approach for large-scale unconstrained optimization, we develop the use of efficient multilevel schemes for computing the optical flow. More precisely, we evaluate the performance of a standard unidirectional multilevel algorithm - called multiresolution optimization (MR/OPT), to a bidrectional multilevel algorithm - called full multigrid optimization (FMG/OPT). The FMG/OPT algorithm treats the coarse grid correction as an optimization search direction and eventually scales it using a line search. Experimental results on different image sequences using four models of optical flow computation show that the FMG/OPT algorithm outperforms both the TN and MR/OPT algorithms in terms of the computational work and the quality of the optical flow estimation.

QoS online routing and MPLS multilevel protection: a survey

A survey of MPLS protection methods and their utilization in combination with online routing methods is presented in this article. Usually, fault management methods pre-establish backup paths to recover traffic after a failure. In addition, MPLS allows the creation of different backup types, and hence MPLS is a suitable method to support traffic-engineered networks. In this article, an introduction of several label switch path backup types and their pros and cons are pointed out. The creation of an LSP involves a routing phase, which should include QoS aspects. In a similar way, to achieve a reliable network the LSP backups must also be routed by a QoS routing method. When LSP creation requests arrive one by one (a dynamic network scenario), online routing methods are applied. The relationship between MPLS fault management and QoS online routing methods is unavoidable, in particular during the creation of LSP backups. Both aspects are discussed in this article. Several ideas on how these actual technologies could be applied together are presented and compared

Associationism and electoral participation: A multilevel study of 2000 Spanish general election

This work presents an application of the multilevel analysis techniques tothe study of the abstention in the 2000 Spanish general election. Theinterest of the study is both, substantive and methodological. From thesubstantive point of view the article intends to explain the causes ofabstention and analyze the impact of associationism on it. From themethodological point of view it is intended to analyze the interaction betweenindividual and context with a modelisation that takes into account thehierarchical structure of data. The multilevel study of this paper validatesthe one level results obtained in previous analysis of the abstention andshows that only a fraction of the differences in abstention are explained bythe individual characteristics of the electors. Another important fraction ofthese differences is due to the political and social characteristics of thecontext. Relating to associationism, the data suggest that individualparticipation in associations decrease the probability of abstention. However,better indicators are needed in order to catch more properly the effect ofassociationism in electoral behaviour.

A multilevel analysis on the determinants of regional health care expenditure. A note

We apply a multilevel hierarchical model to explore whether anaggregation fallacy exists in estimating the income elasticity of healthexpenditure by ignoring the regional composition of national healthexpenditure figures. We use data for 110 regions in eight OECD countriesin 1997: Australia, Canada, France, Germany, Italy, Spain, Sweden andUnited Kingdom. In doing this we have tried to identify two sources ofrandom variation: within countries and between-countries. Our resultsshow that: 1- Variability between countries amounts to (SD) 0.5433, andjust 13% of that can be attributed to income elasticity and the remaining87% to autonomous health expenditure; 2- Within countries, variabilityamounts to (SD) 1.0249; and 3- The intra-class correlation is 0.5300. Weconclude that we have to take into account the degree of fiscaldecentralisation within countries in estimating income elasticity ofhealth expenditure. Two reasons lie behind this: a) where there isdecentralisation to the regions, policies aimed at emulating diversitytend to increase national health care expenditure; and b) without fiscaldecentralisation, central monitoring of finance tends to reduce regionaldiversity and therefore decrease national health expenditure.

Line search multilevel optimization as computational methods for dense optical flow

We evaluate the performance of different optimization techniques developed in the context of optical flow computation with different variational models. In particular, based on truncated Newton methods (TN) that have been an effective approach for large-scale unconstrained optimization, we de- velop the use of efficient multilevel schemes for computing the optical flow. More precisely, we evaluate the performance of a standard unidirectional mul- tilevel algorithm - called multiresolution optimization (MR/OPT), to a bidrec- tional multilevel algorithm - called full multigrid optimization (FMG/OPT). The FMG/OPT algorithm treats the coarse grid correction as an optimiza- tion search direction and eventually scales it using a line search. Experimental results on different image sequences using four models of optical flow com- putation show that the FMG/OPT algorithm outperforms both the TN and MR/OPT algorithms in terms of the computational work and the quality of the optical flow estimation.

Multilevel control of arabidopsis 3-hydroxy-3-methylglutaryl coenzyme A reductase by protein phosphatase 2A

Plants synthesize a myriad of isoprenoid products that are required both for essential constitutive processes and for adaptive responses to the environment. The enzyme 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) catalyzes a key regulatory step of the mevalonate pathway for isoprenoid biosynthesis and is modulated by many endogenous and external stimuli. In spite of that, no protein factor interacting with and regulating plant HMGR in vivo has been described so far. Here, we report the identification of two B99 regulatory subunits of protein phosphatase 2A (PP2A), designated B99a and B99b, that interact with HMGR1S and HMGR1L, the major isoforms of Arabidopsis thaliana HMGR. B99a and B99b are Ca2+ binding proteins of the EF-hand type. We show that HMGR transcript, protein, and activity levels are modulated by PP2A in Arabidopsis. When seedlings are transferred to salt-containing medium, B99a and PP2A mediate the decrease and subsequent increase of HMGR activity, which results from a steady rise of HMGR1-encoding transcript levels and an initial sharper reduction of HMGR protein level. In unchallenged plants, PP2A is a posttranslational negative regulator of HMGR activity with the participation of B99b. Our data indicate that PP2A exerts multilevel control on HMGR through the fivemember B99 protein family during normal development and in response to a variety of stress conditions.

Diseño de filtros con topología apilada mediante resonadores FBAR

Els continguts de la memòria es divideixen en dues parts fonamentals, precedides d’una breu explicació on s’introdueix al lector en el tema; primer s’exposen les bases d’un ressonador simple FBAR, d’on s’obtenen equacions de control vitals, i seguidament es plantegen les bases per a un ressonador apilat SCR, derivades de l’estudi previ d’un ressonador simple. La primera part fonamental del treball es centra en l’anàlisi d’un ressonador SCR. Aquest anàlisi es recolza sobre el punt de vista teòric dels paràmetres imatge, el nostre punt de sortida. Aquesta primera part és la més teòrica: obtenció i aplicació dels paràmetres imatge i obtenció dels elements discrets que conformen el circuit equivalent SCR, una xarxa de dos ports. Posteriorment, s’analitza què succeeix modificant els valors dels elements discrets sense variar determinats paràmetres imatge i finalment, es proposa una aproximació per a controlar determinades especificacions de disseny, com són l’ample de banda de transmissió de la xarxa i el factor de qualitat, en funció de les modificacions dels elements discrets. En la segona part s’analitzen, de forma qualitativa, xarxes compostes per diferents ressonadors apilats connectats en cascada. Aquest segon estudi es divideix en dues subparts. En la primera connectem N ressonadors idèntics, plantegem algunes equacions de control i analitzem les respostes. En la segona, es planteja la connexió de dos (N=2) ressonadors diferents amb freqüències de ressonància properes. Aquest segon anàlisi es també totalment qualitatiu, però ens aporta informació que amb la unió de N ressonadors iguals no aconseguíem. Finalitzant aquesta segona part, es planteja l’optimització dels resultats obtinguts per a N=2, mitjançant estructures N=3 ressonadors.

Diseño e implementación de un divisor de potencia en banda dual con estructuras metamateriales basadas en CSRRs

L'electromagnetisme és una branca de la física que està en continu estudi. Fins a mitjans de la dècada dels 60 es pensava que, per a la propagació de les ones electromagnètiques fos possible, els medis propagatius havien de presentar una permitivitat dielèctrica i una permeabilitat magnètica simultàniament positives. No obstant, Victor G. Veselago va revolucionar la teoria electromagnètica amb la idea dels medis amb ε i μ negatives i va donar amb això origen als medis metamaterials. En el present treball s'estudiaran els principis físics en els que es fonamenten els metamaterials. Es veuran algunes de les seves característiques que els converteixen en medis exòtics i com aquestes poden ser utilitzades en el desenvolupament de dispositius amb prestacions difícils d'obtenir amb les tecnologies convencionals. A continuació s'aplicaran els conceptes tractats en el disseny d'un inversor d'impedàncies implementat mitjançant ressonadors en anells oberts complementaris. Aquest dispositiu, que presentarà un funcionament en banda dual, serà utilitzat en el posterior disseny d'un divisor de potencia. Finalment es realitzarà la implementació física del divisor de potencia dissenyat i es verificarà el seu correcte funcionament amb les mesures pertinents.

Relationship between technological progress, capital elasticity and emissions of industrial pollutants for the production sectors in Catalonia

As is known, the Kyoto Protocol proposes to reinforce national policies for emission reduction and, furthermore, to cooperate with other contracting parties. In this context, it would be necessary to assess these emissions, both in general and specifically, by pollutants and/or among productive sectors. The object of this paper is precisely to estimate the polluting emissions of industrial origin in Catalonia in the year 2001, in a multivariate context which explicitly allows a distinction to be made between the polluter and/or the productive sector causing this emission. Six pollutants considered, four directly related to greenhouse effect. A multi-level model, with two levels, pollutants and productive sectors, was specified. Both technological progress and elasticity of capital were introduced as random effects. Hence, it has been permitted that these coefficients vary according to one or other level. The most important finding in this paper is that elasticity of capital has been estimated as very non-elastic, with a range which varies between 0.162 (the paper industry) and 0.556 (commerce). In fact, and generally speaking, the greater capital the sector has, the less elasticity of capital has been estimated. Key words: Kyoto protocol, multilevel model, technological progress

Planificació general a l'aula inclusiva. El cas del Solsonès

El present treball de recerca es centra en l’estudi de la programació general de l’aula en entorns inclusius. Concretament, s’ha dut a terme un estudi de cas a la comarca del Solsonès ja que les característiques demogràfiques i educatives d’aquesta comarca han facilitat la inclusió escolar de tot l’alumnat amb discapacitat a l’aula ordinària. Els principals objectius de la investigació són descriure les pràctiques de planificació general del professorat de la comarca del Solsonès que ha atès a alumnat amb necessitats educatives especials i conèixer els aspectes relacionats amb la programació didàctica que es poden millorar a partir de processos de formació permanent i assessorament. L’anàlisi de la informació recollida a través de qüestionaris realitzats al professorat del Solsonès i un grup de discussió als professionals dels serveis externs, ens ha permès conèixer les pràctiques de planificació del professorat del Solsonès i fins a quin punt són similars a bones pràctiques, com l’Ensenyament Multinivell o el Disseny Universal de l’Aprenentatge, desenvolupades en altres contextos; així com, quins són els principals problemes i dificultats amb què es troben els i les professionals a l’hora de dur a terme les programacions a l’aula.

Intermediary and structural determinants of early childhood health in Colombia: exploring the role of communities

This study examines how structural determinants influence intermediary factors of child health inequities and how they operate through the communities where children live. In particular, we explore individual, family and community level characteristics associated with a composite indicator that quantitatively measures intermediary determinants of early childhood health in Colombia. We use data from the 2010 Colombian Demographic and Health Survey (DHS). Adopting the conceptual framework of the Commission on Social Determinants of Health (CSDH), three dimensions related to child health are represented in the index: behavioural factors, psychosocial factors and health system. In order to generate the weight of the variables and take into account the discrete nature of the data, principal component analysis (PCA) using polychoric correlations are employed in the index construction. Weighted multilevel models are used to examine community effects. The results show that the effect of household’s SES is attenuated when community characteristics are included, indicating the importance that the level of community development may have in mediating individual and family characteristics. The findings indicate that there is a significant variance in intermediary determinants of child health between-community, especially for those determinants linked to the health system, even after controlling for individual, family and community characteristics. These results likely reflect that whilst the community context can exert a greater influence on intermediary factors linked directly to health, in the case of psychosocial factors and the parent’s behaviours, the family context can be more important. This underlines the importance of distinguishing between community and family intervention programmes.

Contextual effects on subjective national identity and nationalist vote in Catalonia

The important inflow of foreign population to western countries has boosted the study of acculturation processes among scholars in the last decades. By using the case of Catalonia, a receiver region of international and national migration since the fifties, this paper seeks to intersect a classic acculturation model and a newly reemerging literature in political science on contextual determinants on individual behavior. Does the context matters for understanding individual’s subjective national identity and, therefore, its voting behavior? Multilevel models show that environment matters. Percentage of Spain-born population in the town is statistically significant to account for variance in the subjective national identity and nationalist vote, even after controlling for age, sex, origin, language and left – right orientation and other contextual factors. This conclusion invites researchers not to underestimate the direct effect of the environment on individual outcomes such as feelings of belonging and vote orientation in contexts of rival identities.

Social Determinants of Child Health in Colombia: Can Community Education Moderate the Effect of Family Characteristics?

Contextual effects on child health have been investigated extensively in previous research. However, few studies have considered the interplay between community characteristics and individual-level variables. This study examines the influence of community education and family socioeconomic characteristics on child health (as measured by height and weight-for-age Z-scores), as well as their interactions. We adapted the Commission on Social Determinants of Health (CSDH) framework to the context of child health. Using data from the 2010 Colombian Demographic and Health Survey (DHS), weighted multilevel models are fitted since the data are not self-weighting. The results show a positive impact of the level of education of other women in the community on child health, even after controlling for individual and family socioeconomic characteristics. Different pathways through which community education can substitute for the effect of family characteristics on child nutrition are found. The interaction terms highlight the importance of community education as a moderator of the impact of the mother’s own education and autonomy, on child health. In addition, the results reveal differences between height and weight-for-age indicators in their responsiveness to individual and contextual factors. Our findings suggest that community intervention programmes may have differential effects on child health. Therefore, their identification can contribute to a better targeting of child care policies.

The Nationalism of stateless nations and Europe. The Catalan case

This paper analyzes how the ideas and concepts of Europe have developed in Catalonia, under the conditions of a decentralizing “nation-state” (Spain) on one hand, and the European integration process on the other. It analyzes the programmes, manifestations of political leaders, and political actions of the Catalan political parties, specially the nationalists, from the setting up of the Spanish state of autonomies (1977-1982) until today. The paper tries to show how, in multilevel governance, holistic and enthusiastic visions of an economically and political integrating Europe as a “natural ally” of a Catalan nationalism were partially replaced by more pragmatic and even more critical assessments.

Asessing public policies. The case of education in Europe and the interaction between personal and institutional factors

The paper deals with the comparative study of European citizens' satisfaction with the state of education in their respective countries. Individual and contextual effects are tested applying multilevel analysis. The results show that educational public policies (level of decentralization, degree of comprehensiveness and public spending) as well as the students' social environment (socioeconomic and cultural status) have a sound impact on the opinions about the state of education.