821 research outputs found

    Galois Connections between Semimodules and Applications in Data Mining

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    In [1] a generalisation of Formal Concept Analysis was introduced with data mining applications in mind, K-Formal Concept Analysis, where incidences take values in certain kinds of semirings, instead of the standard Boolean carrier set. A fundamental result was missing there, namely the second half of the equivalent of the main theorem of Formal Concept Analysis. In this continuation we introduce the structural lattice of such generalised contexts, providing a limited equivalent to the main theorem of K-Formal Concept Analysis which allows to interpret the standard version as a privileged case in yet another direction. We motivate our results by providing instances of their use to analyse the confusion matrices of multiple-input multiple-output classifiers

    10-Undecenoic acid-based biodegradable hydroxy polyesters: a platform for aminoacid bioconjugates and PEG-derived amphiphilic copolymers.

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    El gran desenvolupament que actualment estan experimentant els biopolímers es deu fonamentalment als alts preus i a la disminució de les reserves de petroli, juntament amb la preocupació que existeix avui en dia en matèria de sostenibilitat ambiental. Entre els polímers d'origen renovable, els polièsters alifàtics són dels més estudiats ja que es consideren molt adequats per aplicacions com a biomaterials a causa de la seva biocompatibilitat i biodegradabilitat. En aquesta tesi s'han preparat polièsters renovables mitjançant química sostenible i utilitzant derivats de l'oli de ricí, com a producte de partença. Concretament, s'han fet servir reaccions amb àcid 10-undecenoïc per obtenir els monòmers, que contenen grups funcionals àcid carboxílic i epòxid o alcohol. Tots dos tipus de monòmer són capaços d'experimentar polimerització, obtenint així polímers lineals i ramificats amb grups hidroxilo funcionalitzables. S'ha demostrat que aquests polímers són degradables enzimàtica i hidrolíticament. A més a més s'han modificat aquests polièsters amb diferents biomolècules com els aminoàcids. Finalment, utilitzant enzims com a catalitzador s'han sintetitzat copoliésters de bloc i d’empelt a partir d'aquests monòmers o polièsters i derivats del polietilenglicol. Com a resultat s’han obtingut polímers amfifílics capaços de formar micel·les en les quals és possible encapsular drogues per ser alliberades de forma controlada.El gran desarrollo que están experimentando actualmente los biopolímeros se debe fundamentalmente a los altos precios y disminución de las reservas de petróleo, junto con la preocupación que existe hoy en día en materia de sostenibilidad ambiental. Entre los polímeros de origen renovable los poliésteres alifáticos son los que se han estudiado en mayor profundidad por ser los más adecuados como biomateriales, debido a su biocompatibilidad y biodegradabilidad. En esta tesis se han preparado poliésteres renovables mediante química sostenible y el uso de derivados de aceite de ricino como materia de partida. Concretamente, se han usado reacciones a partir del ácido 10-undecenoico para obtener monómeros que contienen grupos funcionales ácido carboxílico y epóxido o alcohol. Ambos monómeros son capaces de experimentar polimerización, obteniendo así polímeros lineales y ramificados con grupos hidroxilo funcionalizables. Se ha demostrado que estos polímeros son degradables enzimática e hidrolíticamente. Además, estos poliésteres se han modificado con diferentes biomoléculas como aminoácidos. Finalmente, utilizando enzimas como catalizador se han sintetizado copoliésteres de bloque y de injerto a partir de estos monómeros o poliésteres y derivados del polientilenglicol. Como resultado, se han obtenido polímeros amfifílicos capaces de formar micelas, en las cuales es posible encapsular drogas para ser liberadas de forma controlada.Currently biopolymers experienced a great development due to the high prices and decrease of petroleum reserves along with the concern increasing in terms of environmental sustainability. Aliphatic polyesters are among the most studied polymers from renewable resources, because they are considered very suitable for applications as biomaterials due to their biocompatibility and biodegradability. In this thesis, renewable polyesters have been prepared from derivatives of vegetable castor oil and using sustainable chemistry. Specifically, 10-undecenoic acid has been used to synthesize the monomers which contain carboxylic acid and epoxide or alcohol. These monomers by polymerization lead to linear or branched polymers with available reactive hydroxyl groups. It has been shown that these polymers are enzymatically and hydrolytically degradable. In addition, these polyesters have been modified with different biomolecules as aminoacids. Finally, using enzymes as catalyst have been synthesized block and grafted copolyesters from these monomers or polyesters and polyethylene glycol derivatives. As result, amphiphilic polymers capable of forming micelles have been synthesized, which can encapsulate drugs to be released

    Relación de índices lipoproteicos con el síndrome cardiometabólico en pacientes del centro de salud Raúl Porras Barrenechea, Carabayllo 2022

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    La investigación titulada Relación de índices lipoproteicos con el síndrome cardiometabólico en pacientes que asisten al centro de salud Raúl Porras Barrenechea, Carabayllo 2022.El tipo de investigación fue explicativo correlacional, el diseño metodológico fue explicativo. La población estuvo conformada por 250 pacientes adultas y la muestra fueron 152 pacientes seleccionados aleatoriamente. La técnica fue la observación directa y el instrumento fue el registro de resultados del laboratorio. Los resultados que se obtuvieron, fueron procesados en el software estadístico SPSS versión 25, se crearon tablas y gráficos, asimismo se utilizó la correlación de Pearson, prueba chi cuadrado y el análisis de curva ROC (Receiver Operating Characteristic curve) para identificar la capacidad predictiva de los índices lipoproteicos en el SCM. Esta investigación fue de gran importancia porque se conoció que índice lipoproteico es el mejor predictor del SCM para que los pacientes tengan un tratamiento oportuno y por ende, una mejor calidad de vida.Tesi

    Towards the algebraization of Formal Concept Analysis over complete dioids

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    Actas de: XVII Congreso Español sobre Tecnologías y Lógica Fuzzy (ESTYLF 2014). Zaragoza, 5-7 de febrero de 2014.Complete dioids are already complete residuated lattices. Formal contexts with entries in them generate Concept Lattices with the help of the polar maps. Previous work has already established the spectral nature of some formal concepts for contexts over certain kinds of dioids. This paper tries to raise the awareness that linear algebra over exotic semirings should be one place to look to understand the properties of FCA over L-lattices.FJVA was partially supported by EU FP7 project LiMoSINe (contract 288024) for this research. CPM was partially supported by the Spanish Government-Comisión Interministerial de Ciencia y Tecnología project 2011-268007/TEC.Publicad

    Spectral Lattices of reducible matrices over completed idempotent semifields

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    Proceedings of: 10th International Conference on Concept Lattices and Their Applications. (CLA 2013). La Rochelle, France, October 15-18, 2013.Previous work has shown a relation between L-valued extensions of FCA and the spectra of some matrices related to L-valued contexts. We investigate the spectra of reducible matrices over completed idempotent semifields in the framework of dioids, naturally-ordered semirings, that encompass several of those extensions. Considering special sets of eigenvectors also brings out complete lattices in the picture and we argue that such structure may be more important than standard eigenspace structure for matrices over completed idempotent semifields.FJVA is supported by EU FP7 project LiMoSINe (contract 288024). CPM has been partially supported by the Spanish Government-Comisión Interministerial de Ciencia y Tecnología project TEC2011-26807 for this paper.Publicad

    La función tutorial en entornos virtuales de aprendizaje: comunicación y comunidad.

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    La función tutorial es uno de los principales factores que determinan la calidad de la formación en un entorno virtual de aprendizaje. El papel de orientador y guía por parte del profesorado asume un mayor protagonismo en la educación on-line y se hace precisa una formación específica en este campo. El texto describe las características de las herramientas de comunicación sincrónicas y asincrónicas más comunes en los entornos virtuales de aprendizaje y se detiene especialmente en una serie de recomendaciones acerca de lo que se consideran usos correctos de dichas herramientas con relación a los fines comunicativos que persiguen. Por otra parte, el texto define una serie de factores relevantes para la creación de comunidades en entornos virtuales de aprendizaje, entre los que se encuentran la naturaleza del contacto humano virtual; la creación de normas, reglas, reparto de responsabilidades y participación; la gestión del tiempo; la gestión de la información y el tamaño de los grupos.The tutoring on is one of the main factors that determine the quality of the formation in a virtual environment of learning. The text describes the characteristics of the most common synchronous and asynchronous communication tools in the virtual environments of learning and it stops especially in a series of recommendations about what we are considered correct uses of this tools with relationship to the talkative ends that pursue. On the other hand, the text defines a series of outstanding factors for the creation of communities in virtual environments of learning, among those that are the nature of the virtual human contact; the creation of norms, rules, allotment of responsibilities and participation; the management of the time; the management of the information and the size of the groups

    Two Information-Theoretic Tools to Assess the Performance of Multi-class Classifiers

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    We develop two tools to analyze the behavior of multiple-class, or multi-class, classifiers by means of entropic measures on their confusion matrix or contingency table. First we obtain a balance equation on the entropies that captures interesting properties of the classifier. Second, by normalizing this balance equation we first obtain a 2-simplex in a three-dimensional entropy space and then the de Finetti entropy diagram or entropy triangle. We also give examples of the assessment of classifiers with these tools.Spanish Government-Comisión Interministerial de Ciencia y Tecnología projects 2008-06382/TEC and 2008-02473/TEC and the regional projects S-505/TIC/0223 (DGUI-CM) and CCG08-UC3M/TIC-4457 (Comunidad Autónoma de Madrid – UC3M)Publicad

    100% classification accuracy considered harmful: The normalized information transfer factor explains the accuracy paradox

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    The most widely spread measure of performance, accuracy, suffers from a paradox: predictive models with a given level of accuracy may have greater predictive power than models with higher accuracy. Despite optimizing classification error rate, high accuracy models may fail to capture crucial information transfer in the classification task. We present evidence of this behavior by means of a combinatorial analysis where every possible contingency matrix of 2, 3 and 4 classes classifiers are depicted on the entropy triangle, a more reliable information-theoretic tool for classification assessment. Motivated by this, we develop from first principles a measure of classification performance that takes into consideration the information learned by classifiers. We are then able to obtain the entropy-modulated accuracy (EMA), a pessimistic estimate of the expected accuracy with the influence of the input distribution factored out, and the normalized information transfer factor (NIT), a measure of how efficient is the transmission of information from the input to the output set of classes. The EMA is a more natural measure of classification performance than accuracy when the heuristic to maximize is the transfer of information through the classifier instead of classification error count. The NIT factor measures the effectiveness of the learning process in classifiers and also makes it harder for them to "cheat" using techniques like specialization, while also promoting the interpretability of results. Their use is demonstrated in a mind reading task competition that aims at decoding the identity of a video stimulus based on magnetoencephalography recordings. We show how the EMA and the NIT factor reject rankings based in accuracy, choosing more meaningful and interpretable classifiers.Francisco José Valverde-Albacete has been partially supported by EU FP7 project LiMoSINe (contract 288024): www.limosine-project.eu Carmen Peláez Moreno has been partially supported by the Spanish Government-Comisión Interministerial de Ciencia y Tecnología project TEC2011–26807

    Towards Galois Connections over Positive Semifields

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    In this paper we try to extend the Galois connection construction of K-Formal Concept Analysis to handle semifields which are not idempotent. Important examples of such algebras are the extended non-negative reals and the extended non-negative rationals, but we provide a construction that suggests that such semifields are much more abundant than suspected. This would broaden enormously the scope and applications of K-Formal Concept Analysis.CPM & FVA have been partially supported by the Spanish Government-MinECo projects TEC2014-53390-P and TEC2014-61729-EX
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