Search results for "Medo"

Estudio del estado nutricional de estudiantes de educación primaria y secundaria de la provincia de Valencia y su relación con la adherencia a la Die…

2014

Introducción: La obesidad infantil está alcanzando cifras muy elevadas entre la población infantil española favoreciendo la obesidad en la edad adulta. El objetivo del presente estudio es conocer el estado nutricional de estudiantes de seis colegios de la provincia de Valencia y su grado de adhesión a la Dieta Mediterránea (DM).Material y métodos: Estudio transversal en el que participaron 777 estudiantes, 49,9% eran chicos y 50,1% chicas con edades comprendidas entre 8 y 16 años. Se determinó el peso y la altura de cada participante y se calculó el Índice de Masa Corporal (IMC). A partir del IMC se calculó el Z-score. Para determinar el grado de adhesión a la DM se utilizó el test KidMed.R…

SparseHC: A Memory-efficient Online Hierarchical Clustering Algorithm

2014

Computing a hierarchical clustering of objects from a pairwise distance matrix is an important algorithmic kernel in computational science. Since the storage of this matrix requires quadratic space with respect to the number of objects, the design of memory-efficient approaches is of high importance to this research area. In this paper, we address this problem by presenting a memory-efficient online hierarchical clustering algorithm called SparseHC. SparseHC scans a sorted and possibly sparse distance matrix chunk-by-chunk. Meanwhile, a dendrogram is built by merging cluster pairs as and when the distance between them is determined to be the smallest among all remaining cluster pairs. The k…

Efectividad de una intervención para reducir el miedo a caer en las personas mayores

2014

Objetivo: las caídas y el miedo a caerse se relacionan entre sí, siendo cada uno de ellos factor de riesgo del otro. Este trabajo pretende analizar la efectividad de una intervención para reducir el miedo a caer y sus consecuencias dado que la aplicación de este tipo de tratamientos ha mostrado resultados satisfactorios. Método: mediante un diseño cuasi-experimental, con medidas pre-pos, se evaluó a 53 sujetos, con edades comprendidas entre 65 y 89 años y que habían sufrido una caída anterior. La muestra fue dividida en grupo control y tratamiento, poniéndose en marcha un método combinado de ejercicios y educación sanitaria para la prevención de caídas. Resultados: se obtuvieron resultados …

Structural clustering of millions of molecular graphs

2014

We propose an algorithm for clustering very large molecular graph databases according to scaffolds (i.e., large structural overlaps) that are common between cluster members. Our approach first partitions the original dataset into several smaller datasets using a greedy clustering approach named APreClus based on dynamic seed clustering. APreClus is an online and instance incremental clustering algorithm delaying the final cluster assignment of an instance until one of the so-called pending clusters the instance belongs to has reached significant size and is converted to a fixed cluster. Once a cluster is fixed, APreClus recalculates the cluster centers, which are used as representatives for…

A fast and recursive algorithm for clustering large datasets with k-medians

2012

Clustering with fast algorithms large samples of high dimensional data is an important challenge in computational statistics. Borrowing ideas from MacQueen (1967) who introduced a sequential version of the $k$-means algorithm, a new class of recursive stochastic gradient algorithms designed for the $k$-medians loss criterion is proposed. By their recursive nature, these algorithms are very fast and are well adapted to deal with large samples of data that are allowed to arrive sequentially. It is proved that the stochastic gradient algorithm converges almost surely to the set of stationary points of the underlying loss criterion. A particular attention is paid to the averaged versions, which…

Tiešsaistes Klientu Segmentācija, Izmantojot Klasterizācijas Metodes

2021

Bakalaura darba mērķis ir izpētīt tiešsaistes klientu segmentāciju, lai tā palīdzētu pieņemt loģiskus lēmumus par efektīvu mārketinga un reklāmas resursu izmantošanu. Darbā tika izmantotas divas klasterizācijas metodes: K-Medoīdu (K-Medoids) klasterizācija, un K-Prototipu (K-Prototypes) klasterizācija. Metožu izvēle tiek pamatota ar pētītā uzdevuma raksturojumu. Darba gaitā tiek aprakstīti gan abu metožu teorētiskie aspekti, gan metodes tiek pielietotas praktiski (izmantojot programmu R) konkrēta uzdevuma risināšanai. Tika veikta iegūto rezultātu analīze un salīdzināšana. Bakalaura darbā tika arī paskaidrota klientu segmentācijas nozīme veiksmīgam uzņēmumam, kā arī tika aprakstīts interneta…

Looking for representative fit models for apparel sizing

2014

This paper is concerned with the generation of optimal fit models for use in apparel design. Representative fit models or prototypes are important for defining a meaningful sizing system. However, there is no agreement among apparel manufacturers and each one has their own prototypes and size charts i.e. there is a lack of standard sizes in garments from different apparel manufacturers. We propose two algorithms based on a new hierarchical partitioning around medoids clustering method originally developed for gene expression data. We are concerned with a different application; therefore, the dissimilarity between the objects has to be different and must be designed to deal with anthropometr…

2018

Marine sponges are a very attractive and rich source in the production of novel bioactive compounds. The sponges exhibit a wide range of pharmacological activities. The genus Amphimedon consists of various species, such as viridis, compressa, complanata, and terpenensis, along with a handful of undescribed species. The Amphimedon genus is a rich source of secondary metabolites containing diverse chemical classes, including alkaloids, ceramides, cerebrososides, and terpenes, with various valuable biological activities. This review covers the literature from January 1983 until January 2018 and provides a complete survey of all the compounds isolated from the genus Amphimedon and the associate…

A green and efficient method for the synthesis of homodimeric (β-dicarbonyl) arylmethanes and dihydropyridine from dimedone in water

2018

A direct method has been developed for the synthesis of the dihydropyridine ring system by means of Michael reaction. The reaction of dimedone with 1 .0 equiv. of amines in water provides intermediate product, which allowed dihydropyridine derivatives by intramolecular cyclization in various yields. Of particular interest is the use of the water as solvent of reaction and in absence of catalyst. Also these operating conditions protect the environment and economic points of view.Keywords: aqueous synthesis; bioactivity; dihydropyridine; dimedone; green method; selective conditions

Incrementally Assessing Cluster Tendencies with a~Maximum Variance Cluster Algorithm

2003

A straightforward and efficient way to discover clustering tendencies in data using a recently proposed Maximum Variance Clustering algorithm is proposed. The approach shares the benefits of the plain clustering algorithm with regard to other approaches for clustering. Experiments using both synthetic and real data have been performed in order to evaluate the differences between the proposed methodology and the plain use of the Maximum Variance algorithm. According to the results obtained, the proposal constitutes an efficient and accurate alternative.