Desingularizing bmb^m-symplectic structures

A $2n$-dimensional Poisson manifold $(M ,\Pi)$ is said to be $b^m$-symplectic if it is symplectic on the complement of a hypersurface $Z$ and has a simple Darboux canonical form at points of $Z$ which we will describe below. In this paper we will discuss a desingularization procedure which, for $m$ even, converts $\Pi$ into a family of symplectic forms $\omega_{\epsilon}$ having the property that $\omega_{\epsilon}$ is equal to the $b^m$-symplectic form dual to $\Pi$ outside an $\epsilon$-neighborhood of $Z$ and, in addition, converges to this form as $\epsilon$ tends to zero in a sense that will be made precise in the theorem below. We will then use this construction to show that a number of somewhat mysterious properties of $b^m$-manifolds can be more clearly understood by viewing them as limits of analogous properties of the $\omega_{\epsilon}$'s. We will also prove versions of these results for $m$ odd; however, in the odd case the family $\omega_{\epsilon}$ has to be replaced by a family of folded symplectic forms.Comment: new version, 13 pages, 3 figures, final version accepted at IMRN, International Mathematics Research Notice

Effects of IT-Based Connectivity on Firms\u27 Innovation Capability and Performance

Firms have been investing in portal technologies to enhance employee operations, internal communication, supplier interactions, and customer service. However, the benefits of this expensive enterprise technology have yet to be quantified and the manner of their impact on organizations yet to be understood. Drawing upon social capital theory and the IT investments literature, we propose that firms\u27 investments in portal features that support connectivity internally, and with customers and suppliers enables the firms to develop their innovation capability, which, in turn, enhances firm performance. We test this model using data collected from announcements of firms\u27 portal investments

Toward Improving Predictive Risk Modelling for New Zealand's Child Welfare System Using Clustering Methods

The combination of clinical judgement and predictive risk models crucially assist social workers to segregate children at risk of maltreatment and decide when authorities should intervene. Predictive risk modelling to address this matter has been initiated by several governmental welfare authorities worldwide involving administrative data and machine learning algorithms. While previous studies have investigated risk factors relating to child maltreatment, several gaps remain as to understanding how such risk factors interact and whether predictive risk models perform differently for children with different features. By integrating Principal Component Analysis and K-Means clustering, this paper presents initial findings of our work on the identification of such features as well as their potential effect on current risk modelling frameworks. This approach allows examining existent, unidentified yet, clusters of New Zealand (NZ) children reported with care and protection concerns, as well as to analyse their inner structure, and evaluate the performance of prediction models trained cluster wise. We aim to discover the extent of clustering degree required as an early step in the development of predictive risk models for child maltreatment and so enhance the accuracy of such models intended for use by child protection authorities. The results from testing LASSO logistic regression models trained on identified clusters revealed no significant difference in their performance. The models, however, performed slightly better for two clusters including younger children. our results suggest that separate models might need to be developed for children of certain age to gain additional control over the error rates and to improve model accuracy. While results are promising, more evidence is needed to draw definitive conclusions, and further investigation is necessary.Comment: 20 pages, 5 figures, 6 table

Convexity of the moment map image for torus actions on bmb^m-symplectic manifolds

We prove a convexity theorem for the image of the moment map of a Hamiltonian torus action on a $b^m$-symplectic manifold.Comment: 6 pages, 1 figur

Estudio de los errores y aciertos del marketing electoral ecuatoriano para el perìodo 1979-2002

El presente trabajo repasa las acciones y planteamientos, en cuanto a la estrategia de marketing electoral se refiere, que tomaron los actores que protagonizaron la carrera hacia la presidencia del Ecuador; enmarcado en el inicio del último periodo democrático de nuestro país (1979) hasta las elecciones del año 2002. Al mismo tiempo busca determinar las variables propias de la convivencia en sociedad que afectan al votante ecuatoriano para precisar los factores que priman en la decisión de este al momento de elegir un candidato y, demostrar que el agente emocional supera al racional. Para esto se llevó a cabo investigaciones de campo, entrevistas a expertos en el área y un análisis de mercado que involucró a las parroquias urbanas de Guayaquil que resultaron en el desarrollo y conclusiones de esta tesis

On geometric quantization of b-symplectic manifolds

We study a notion of pre-quantization for b-symplectic manifolds. We use it to construct a formal geometric quantization of b-symplectic manifolds equipped with Hamiltonian torus actions with nonzero modular weight. We show that these quantizations are finite dimensional T-modules.Peer ReviewedPostprint (author's final draft

Fertirrigação e regulador de crescimento na produção de mudas de café em tubete

The use of quality seedlings is important in establishing a productive coffee crop. However, the most widely used method to produce coffee seedlings is time consuming (6-12 months) and lacks new production technologies. This study aimed to assess the use of fertigation and a growth regulator in the production of coffee seedlings, in order to develop a system faster than the conventional method. For that, Topázio coffee cultivar seeds were pre-germinated and planted in tubes flled with substrate (composted pine bark), in a protected nursery. A randomized block design was used, in a 4 x 2 (fertigation levels x the use or not of growth regulator) factorial scheme, with four replications. Daily fertigation positively influenced all the growth variables evaluated. The foliar spraying of the growth regulator had little effect on seedling growth. When compared to the conventional system described in the literature, the coffee seedling production system described here reduced, by around 60 days, the production time and enables a largescale productionA utilização de mudas de boa qualidade é importante para a formação de uma lavoura produtiva de café. Entretanto, o método mais utilizado atualmente para a produção de mudas de cafeeiro é demorado (6-12 meses) e carece de novas tecnologias de produção. Objetivou-se avaliar a utilização de fertirrigação e regulador de crescimento na produção de mudas de cafeeiro, com vistas ao desenvolvimento de um sistema mais rápido que o sistema convencional de produção. Para isso, sementes da cultivar Topázio foram pré-germinadas e plantadas em tubetes com substrato (casca de pinus compostada), em viveiro coberto. Adotou-se o delineamento de blocos ao acaso, em esquema fatorial 4 x 2 (níveis de fertirrigação x utilização ou não de regulador de crescimento), com quatro repetições. A fertirrigação diária influenciou positivamente em todas as variáveis de crescimento analisadas. A pulverização foliar do regulador de crescimento apresentou pouco efeito sobre o crescimento das mudas. Quando comparado ao sistema convencional descrito na literatura, o sistema de produção de mudas de cafeeiro descrito neste trabalho reduziu, em cerca de 60 dias, o tempo de produção e permite a produção em larga escala.info:eu-repo/semantics/publishedVersio

Encuesta de movilidad: uso de la bicicleta en Lima Metropolitana

Este informe presenta la encuesta utilizada dentro de la tesis de Master “Sistema Público de bicicletas en Lima Metropolitana. Una alternativa de movilidad sostenible para la ciudad”, que tiene como finalidad determinara la percepción y disposición que tiene la población respecto a cambiar su actual modo de transporte por la bicicleta. Además, se busca encontrar la opinión de las personas sobre la necesidad de que Lima Metropolitana tenga un Sistema Público de Bicicletas.Preprin