A combined measure for quantifying and qualifying the topology preservation of growing self-organizing maps

The Self-OrganizingMap (SOM) is a neural network model that performs an ordered projection of a high dimensional input space in a low-dimensional topological structure. The process in which such mapping is formed is defined by the SOM algorithm, which is a competitive, unsupervised and nonparametric method, since it does not make any assumption about the input data distribution. The feature maps provided by this algorithm have been successfully applied for vector quantization, clustering and high dimensional data visualization processes. However, the initialization of the network topology and the selection of the SOM training parameters are two difficult tasks caused by the unknown distribution of the input signals. A misconfiguration of these parameters can generate a feature map of low-quality, so it is necessary to have some measure of the degree of adaptation of the SOM network to the input data model. The topologypreservation is the most common concept used to implement this measure. Several qualitative and quantitative methods have been proposed for measuring the degree of SOM topologypreservation, particularly using Kohonen's model. In this work, two methods for measuring the topologypreservation of the Growing Cell Structures (GCSs) model are proposed: the topographic function and the topology preserving map

Computing the Hessenberg matrix associated with a self-similar measure

We introduce in this paper a method to calculate the Hessenberg matrix of a sum of measures from the Hessenberg matrices of the component measures. Our method extends the spectral techniques used by G. Mantica to calculate the Jacobi matrix associated with a sum of measures from the Jacobi matrices of each of the measures. We apply this method to approximate the Hessenberg matrix associated with a self-similar measure and compare it with the result obtained by a former method for self-similar measures which uses a fixed point theorem for moment matrices. Results are given for a series of classical examples of self-similar measures. Finally, we also apply the method introduced in this paper to some examples of sums of (not self-similar) measures obtaining the exact value of the sections of the Hessenberg matrix.

A collaborative filtering similarity measure based on singularities.

Recommender systems play an important role in reducing the negative impact of informa- tion overload on those websites where users have the possibility of voting for their prefer- ences on items. The most normal technique for dealing with the recommendation mechanism is to use collaborative filtering, in which it is essential to discover the most similar users to whom you desire to make recommendations. The hypothesis of this paper is that the results obtained by applying traditional similarities measures can be improved by taking contextual information, drawn from the entire body of users, and using it to cal- culate the singularity which exists, for each item, in the votes cast by each pair of users that you wish to compare. As such, the greater the measure of singularity result between the votes cast by two given users, the greater the impact this will have on the similarity. The results, tested on the Movielens, Netflix and FilmAffinity databases, corroborate the excellent behaviour of the singularity measure proposed.

A Balanced Memory-Based Collaborative Filtering Similarity Measure.

Collaborative filtering recommender systems contribute to alleviating the problem of information overload that exists on the Internet as a result of the mass use of Web 2.0 applications. The use of an adequate similarity measure becomes a determining factor in the quality of the prediction and recommendation results of the recommender system, as well as in its performance. In this paper, we present a memory-based collaborative filtering similarity measure that provides extremely high-quality and balanced results; these results are complemented with a low processing time (high performance), similar to the one required to execute traditional similarity metrics. The experiments have been carried out on the MovieLens and Netflix databases, using a representative set of information retrieval quality measures.

Obtaining contradiction measure on intuitionistic fuzzy sets from fuzzy connectives

In a previous paper, we proposed an axiomatic model for measuring self-contradiction in the framework of Atanassov fuzzy sets. This way, contradiction measures that are semicontinuous and completely semicontinuous, from both below and above, were defined. Although some examples were given, the problem of finding families of functions satisfying the different axioms remained open. The purpose of this paper is to construct some families of contradiction measures firstly using continuous t-norms and t-conorms, and secondly by means of strong negations. In both cases, we study the properties that they satisfy. These families are then classified according the different kinds of measures presented in the above paper.

A methodology to measure the interface shear strength by means of the fiber push-in test

A methodology is presented to measure the fiber/matrix interface shear strength in composites. The strategy is based on performing a fiber push-in test at the central fiber of highly-packed fiber clusters with hexagonal symmetry which are often found in unidirectional composites with a high volume fraction of fibers. The mechanics of this test was analyzed in detail by means of three-dimensional finite element simulations. In particular, the influence of different parameters (interface shear strength, toughness and friction as well as fiber longitudinal elastic modulus and curing stresses) on the critical load at the onset of debonding was established. From the results of the numerical simulations, a simple relationship between the critical load and the interface shear strength is proposed. The methodology was validated in an unidirectional C/epoxy composite and the advantages and limitations of the proposed methodology are indicated.

Topological measure locating the effective crossover between segregation and integration in a modular network

We introduce an easily computable topological measure which locates the effective crossover between segregation and integration in a modular network. Segregation corresponds to the degree of network modularity, while integration is expressed in terms of the algebraic connectivity of an associated hypergraph. The rigorous treatment of the simplified case of cliques of equal size that are gradually rewired until they become completely merged, allows us to show that this topological crossover can be made to coincide with a dynamical crossover from cluster to global synchronization of a system of coupled phase oscillators. The dynamical crossover is signaled by a peak in the product of the measures of intracluster and global synchronization, which we propose as a dynamical measure of complexity. This quantity is much easier to compute than the entropy (of the average frequencies of the oscillators), and displays a behavior which closely mimics that of the dynamical complexity index based on the latter. The proposed topological measure simultaneously provides information on the dynamical behavior, sheds light on the interplay between modularity and total integration, and shows how this affects the capability of the network to perform both local and distributed dynamical tasks.

Ensayos de seguridad eléctrica orientados a la vigilancia del mercado

El presente estudio recopila los diferentes bancos de pruebas de EMC, Radio, SAR y seguridad eléctrica que se utiliza en la vigilancia del mercado. Describe las pruebas realizadas por el Estado español para llevar a cabo el seguimiento y control de los equipos vendidos. En primer lugar se presenta una descripción cualitativa de los ambientes clasificados por requisitos que explica en qué consisten las pruebas que se hacen, cómo se configura el entorno de medida y cuáles son los equipos que se deben utilizar. Está ilustrado con fotografías de los bastidores, antenas, amplificadores, generadores y otros equipos que la SETSI tiene en su laboratorio en El Casar (Guadalajara). La vigilancia de los equipos se realiza periódicamente en los estados miembros de la Unión Europea. Los funcionarios responsables también se reúnen periódicamente a nivel europeo para sacar conclusiones y hacer proyecciones futuras. El equipo adquirido en centros comerciales de venta al público, después de poco más de un mes, en el que se pasan las pruebas, vuelve a la cadena de comercialización, por lo que los dispositivos no se puedan dañar. Las pruebas realizadas en el laboratorio no pueden ser perjudiciales para los dispositivos por lo que es necesario tomar precauciones en la ejecución de las pruebas. El centro del PFC es el área de la Seguridad Eléctrica. El capítulo 4 es una reproducción de la Norma internacional IEC 60950-1:2007/A11 sobre seguridad en equipos de tecnología de la información adaptada a los requisitos de la vigilancia de mercado. Las autoridades competentes se basan en este estándar para evaluar y garantizar la seguridad del usuario en los equipos de consumo. Diseñados los procedimientos de ensayo y montado un banco de acuerdo a estos ensayos, se ha preparado un manual de operador, capítulo 5, en el que se recogen cada una de las pruebas y controles visuales que deben realizarse para probar que el equipo es conforme. Para finalizar, en el capítulo 6, se ejecutan ensayos de ejemplo sobre tres dispositivos de prueba y se elaboran las correspondientes hojas de ensayo. El propósito es proporcionar al operador un manual completo del banco de seguridad eléctrica, es por ello que en el manual de operador se han repetido muchos fragmentos de la norma para facilitar al operador el objetivo concreto de las pruebas y el acceso fácil a la información. This dissertation presents the different test benches of EMC, Radio, SAR and Electrical Safety that are used in market surveillance. Describes the tests performed by the Spanish State to carry out the monitoring and control of equipment sold. First a qualitative description of the environments classified by requisites that explains in that consist the tests that are make it, how it configures the measure environment and which are the equipment that it should use. It is illustrated with photographs of the racks, antennas, amplifiers, generators and other equipment that the S.E.T.S.I has in its laboratory on El Casar (Guadalajara). The surveillance of equipment is performed periodically in the member states of the European Union. Responsible officials also periodically meet at European level to draw conclusions and make future projections. The equipment purchased in malls public sale, after little more than a month, in which the tests are passed, returned to the trade chain, which is why the devices cannot be damaged. The tests done in the laboratory may not be harmful for devices are thus necessary to take precautions in the execution of the tests. The center of this dissertation is the area of Electrical Safety. Chapter 4 is a reproduction of the International Standard IEC 60950-1:2007/A11 safety in teams of information technology, adapted to the requirements of market surveillance. The competent authorities are based on this standard to assess and ensure the user's safety in the consumption equipment. Designed test procedures and mounted on a bench according to these tests, it has prepared a manual operator, in Chapter 5, with each of the tests and visual inspections in order to prove that the equipment complies. Finally, in Chapter 6, such tests run on three devices are developed test and test some leaves. The purpose of this book is to provide an operator manual of the bench of electrical safety, which is why the operator manual have been repeated fragments of the standard, in chapter 5, to facilitate the operator to test execution and access to information.

Dominance intensity measure within fuzzy weight oriented MAUT: an application

We introduce a dominance intensity measuring method to derive a ranking of alternatives to deal with incomplete information in multi-criteria decision-making problems on the basis of multi-attribute utility theory (MAUT) and fuzzy sets theory. We consider the situation where there is imprecision concerning decision-makers’ preferences, and imprecise weights are represented by trapezoidal fuzzy weights.The proposed method is based on the dominance values between pairs of alternatives. These values can be computed by linear programming, as an additive multi-attribute utility model is used to rate the alternatives. Dominance values are then transformed into dominance intensity measures, used to rank the alternatives under consideration. Distances between fuzzy numbers based on the generalization of the left and right fuzzy numbers are utilized to account for fuzzy weights. An example concerning the selection of intervention strategies to restore an aquatic ecosystem contaminated by radionuclides illustrates the approach. Monte Carlo simulation techniques have been used to show that the proposed method performs well for different imprecision levels in terms of a hit ratio and a rank-order correlation measure.

Categorical Structures in Non-Commutative Measure Theory.

In this paper, we investigate effect algebras and base normed spaces from the categorical point of view. We prove that the category of effect algebras is complete and cocomplete as well as the category of base normed spaces is complete, and discuss the contravariant functor from the category of effect algebras to the category of base normed spaces.

Methodologies to measure and to manage the decarbonisation of road transport: the case of Spain

El sector del transporte por carretera es uno de los principales contribuyentes de consumo de combustible y emisiones de España. Por lo tanto, la evaluación de los impactos ambientales del tráfico rodado es esencial para los programas de mitigación del cambio climático y la eficiencia energética. Sin embargo, uno de los retos en la planificación del transporte y el diseño de políticas consiste en la aplicación de metodologías de evaluación de emisiones consistentes, el diseño de estrategias y la evaluación de su eficacia. Las metodologías existentes de evaluación de las emisiones del transporte por carretera, utilizan diferentes niveles de análisis y períodos. Sin embargo, estos análisis son puntuales y no existe una continuidad en el análisis de diferentes estrategias o políticas. Esta tesis doctoral proporciona conocimientos y herramientas para el análisis de las políticas destinadas a reducir las emisiones de tráfico, tomando España como caso de estudio. La investigación se estructura en dos partes: i) el desarrollo y aplicación de metodologías para el análisis de factores y políticas que contribuyen en la evolución de las emisiones GEI del transporte por carretera en España; desde una perspectiva nacional; y ii) el desarrollo y aplicación de un marco metodológico para estimar las emisiones del tráfico interurbano y de evaluar estrategias centradas en la operación del tráfico y en la infraestructura. En resumen, esta tesis demuestra la idoneidad de utilizar diferentes herramientas para analizar las emisiones de tráfico desde diferentes puntos de vista. Desde el diseño de políticas de mitigación y eficiencia energética a nivel nacional, a estrategias centradas en la operación del tráfico interurbano y la infraestructura. Road transport is one of the major contributors to fuel consumption and emissions in Spain. Consequently, assessing the environmental impacts of road traffic is essential for climate change mitigation and energy efficiency programs. However, one of the key challenges of policy makers and transport planners consists of implementing consistent assessment emissions methodologies, applying mitigation strategies, and knowing their effectiveness. Current state-of-the-art emissions assessment methodologies estimate emissions from different levels and periods, using different approaches. Nevertheless, these studies are timely and they usually take different methodologies for analysing different strategies or policies, regardless of the assessment as a whole. This doctoral thesis provides knowledge and methodologies for analysing policies designed to reduce road traffic emissions, using the case study of Spain. The research procedure consists of two main scopes: i) the development and application of methodologies for analysing key factors and policies driving the GHG emissions of road transport in Spain; from a national perspective; and ii) the development and application of a road traffic emissions model for assessing operational and infrastructure strategies of the interurban road network at segment level. In summary, this thesis demonstrates the appropriateness to use different tools to analyse road traffic emissions at different levels: from appropriate nationwide mitigation and energy efficiency policies, to strategies focused on the operation of interurban traffic and infrastructure.

A CO2-saving-based methodology to measure the impact of the SUMP in European Cities: Application to the City of Burgos

Urban mobility in Europe is always a responsibility of the municipalities which propose measures to reduce CO2 emissions in terms of mobility aimed at reducing individual private transport (car). The European Commission's Action Plan on Urban Mobility calls for an increase in the take-up of Sustainable Urban Mobility Plans in Europe. SUMPs aim to create a sustainable urban transport system. Europe has got some long term initiatives and has been using some evaluation procedures, many of them through European projects. Nevertheless, the weak point with the SUMPs in Spain, has been the lack of concern about the evaluation and the effectiveness of the measures implemented in a SUMP. For this reason, it is difficult to know exactly whether or not the SUMPs have positively influenced in the modal split of the cities, and its contribution to reduce CO2 levels. The case of the City of Burgos is a very illustrative example as it developed a CiViTAS project during the years 2005-2009, with a total investment of 6M?. The results have been considered as ?very successful? even at European level. The modal split has changed considerably for better, The cost-effectiveness ratio of the SUMP in the city can be measured with the CO2 ton saved, specifically 36 ? per CO2 ton saved, which is fully satisfactory and in line with calculations from other European researchers. Additionally, the authors propose a single formula to measure the effectiveness of the activities developed under the umbrella of a SUMP.

Designing new cereal cultivars as an adaptation measure using crop model ensembles

To date, crop models have been little used for characterising the types of cultivars suited to a changed climate, though simulations of altered management (e.g. sowing) are often reported. However, in neither case are model uncertainties evaluated at the same time.

Perfil antropométrico y respuesta psico-fisiológica en escalada deportiva en roca: Diferencias entre modalidades

En la literatura se ha descrito el perfil antropométrico y la respuesta psicofisiológica en escalada deportiva en roca, pero hasta la fecha, no se habían analizado las diferencias existentes entre sus principales modalidades. El objetivo de la presente tesis fue describir las características antropométricas del escalador de competición y comprobar la existencia de diferencias entre los participantes de distintas modalidades, así como analizar la respuesta psico-fisiológica durante la ejecución de un búlder y una vía, además de evaluar las diferencias entre su realización a vista o tras un ensayo. Para ello, efectuamos dos estudios diferentes: en el primero participaron voluntariamente 61 hombres y 18 mujeres, participantes en cuatro pruebas del circuito nacional de competición de escalada durante el año 2009, tres de ellas de la modalidad de dificultad a vista y una de búlder. Se realizaron mediciones antropométricas, prueba de fuerza de prensión manual antes y después de competir, y se cumplimentó un cuestionario donde se evaluaba la percepción del esfuerzo y la experiencia deportiva. En el segundo estudio, 23 escaladores, 15 hombres y 8 mujeres, divididos en tres grupos en función de su nivel de rendimiento, realizaron de manera voluntaria distintas pruebas durante tres días separados entre sí al menos 48 horas. El primer día rellenaron un cuestionario sobre su experiencia deportiva y nivel de rendimiento, fueron pesados, tallados y sometidos a un escáner de cuerpo completo en densitómetro con objeto de medir la composición corporal. El segundo día realizaron previo calentamiento, un búlder a vista y, tras un descanso de 15 minutos, escalaron una vía a vista acorde con su nivel. El tercer día, después de calentar y disponer de 20 minutos para ensayarlo, repitieron la escalada del búlder. Tras un descanso de 15 minutos y 20 minutos de ensayo, realizaron un segundo intento a la vía. Se registraron los valores en la respuesta cardiorrespiratoria, se obtuvieron muestras de lactato en sangre del lóbulo de la oreja y se realizaron pruebas de fuerza de prensión manual antes y después de la escalada. También se pasó un cuestionario para medir la ansiedad y autoconfianza así como el esfuerzo percibido. Los resultados no mostraron diferencias antropométricas significativas entre los participantes en competiciones de búlder y los que participaron en competiciones de escalada de dificultad a vista. Se dieron diferencias en la pérdida de fuerza antes y después de escalar entre dichos participantes. Las mujeres obtuvieron menor fuerza de prensión manual que los hombres pero la misma pérdida de fuerza entre el instante antes de competir y el posterior. La respuesta fisiológica durante la ejecución del búlder fue menor que la obtenida durante la ejecución de la vía. Hubo pérdida de fuerza de prensión manual entre el instante anterior y el posterior a ejecutar la vía, pero no al hacer el búlder. Sin embargo, no se dieron diferencias en la ansiedad y la autoestima provocada por ambas modalidades, por lo que deducimos que la ejecución de un búlder y una vía presentan una respuesta fisiológica distinta. Proponemos que la respuesta está relacionada, sobre todo, con las variables de ejecución, de tal manera que a mayor distancia y/o tiempo recorrido en la escalada, mayor será la contribución anaeróbica al esfuerzo y la fatiga manifestada como pérdida de fuerza que, en el caso del búlder, fue mínima o inexistente. En el segundo intento, tras un ensayo de 20 minutos en el búlder, se consiguió mejorar el rendimiento respecto al primer intento, que se manifestó con un aumento en la distancia recorrida. Sin embargo, en la vía no se dieron diferencias entre ambos intentos, ni en la ejecución, ni en la respuesta fisiológica, ni en la ansiedad, ni siquiera en la fuerza de prensión manual. ABSTRACT It has been described in the literature the anthropometric profile and psychophysiological response in rock climbing, but so far not been analyzed differences between its main modalities. The aim of this thesis was to describe the anthropometric characteristics of the climber competitor and check for differences between participants of different modalities and to analyze the psycho-physiological response during the execution of a boulder and a route also to assess differences between on sight and redpoint attempts. We made two different studies: in the first 61 men and 18 women who attended four competitions of national climbing circuit in 2009, three of them on-sight difficulty competitions and a boulder competition participated voluntarily. Anthropometric measurements, a hand grip strength test before and after competing were registered for each climber, and a questionnaire which assessed perception of effort and the climbing experience was fulfilled. In the second study, various tests were conducted on 23 volunteer climbers, 15 men and 8 women, during three days separated for, at least, 48 hours of resting, divided into three groups according to their performance. The first day, climbers completed a questionnaire on their experience and performance level. It was recorded weight, height and they underwent a full body scan densitometer in order to measure body composition. The second day, after previous warming-up, they climbed a boulder on sight and, after a break of 15 minutes, climbed a route on-sight according to their level. The third day, after warming-up and have 20 minutes to try it, they repeated the bouldering climbing. After a break of 15 minutes and 20 minutes of essaying, they made a second attempt at the route. Values in the cardiorespiratory response were recorded, blood lactate samples were obtained from earlobe, and hand grip strength was tested before and after the climb. They also filled a questionnaire to measure anxiety and self-confidence and perceived exertion. The results showed no significant anthropometric differences between participants in bouldering competitions and participants in competitions on-sight difficulty climbing. There were found differences in strength loss before and after climbing between those participants. Women had less hand grip strength than men but the same loss of strength between the records carried out before and after competing. The physiological response recorded for boulder climbing was lower than the obtained for the route. There was loss of hand grip strength between the time before and after running the route but not for bouldering. However, there were no differences in anxiety and self-esteem caused by both modalities, so we conclude that the implementation of a boulder and a route have different physiological responses. We think that this response is mainly related to performance variables, as a greater distance and/or travel time on the climb, the higher the anaerobic contribution to the effort and fatigue as manifested by loss of strength in the case of the boulder was minimal or nonexistent. In the second attempt after 20 minutes in the boulder better performance was achieved on the first attempt, which was manifested by an increment of climbing distance. However, there were the differences in the route between the two attempts, either in execution or in the physiological response, or anxiety, or even in hand grip strength.

Relevance of Higher Education. How to measure it? The case of masters of engineering in Peru

Existing evaluation models for higher education have, mainly, accreditation purposes, and evaluate the efficiency of training programs, that is to say, the degree of suitability between the educational results and the objectives of the program. However, it is not guaranteed that those objectives adequate to the needs and real interests of students and stakeholders, that is to say, they do not assess the relevance of the programs, a very important aspect in developing countries. From the review of experiences, this paper proposes a model for evaluating the relevance of engineering masters program, and applies it to the case of a master?s degree at the University of Piura, Peru. We conclude that the proposed model is applicable to other masters program, offers an objective way for determining is a training program keep being relevant, and identifies improvement opportunities