942 resultados para categorization IT PFC computational neuroscience model HMAX
Resumo:
Madagascar is currently developing a policy and strategies to enhance the sustainable management of its natural resources, encouraged by United Nations Framework Convention on Climate Change (UNFCCC) and REDD. To set up a sustainable financing scheme methodologies have to be provided that estimate, prevent and mitigate leakage, develop national and regional baselines, and estimate carbon benefits. With this research study this challenge was tried to be addressed by analysing a lowland rainforest in the Analanjirofo region in the district of Soanierana Ivongo, North East of Madagascar. For two distinguished forest degradation stages: “low degraded forest” and “degraded forest” aboveground biomass and carbon stock was assessed. The corresponding rates of carbon within those two classes were calculated and linked to a multi-temporal set of SPOT satellite data acquired in 1991, 2004 and 2009. Deforestation and particularly degradation and the related carbon stock developments were analysed. With the assessed data for the 3 years 1991, 2004 and 2009 it was possible to model a baseline and to develop a forest prediction for 2020 for Analanjirofo region in the district of Soanierana Ivongo. These results, developed applying robust methods, may provide important spatial information regarding the priorities in planning and implementation of future REDD+ activities in the area.
Resumo:
Spatial independent component analysis (sICA) of functional magnetic resonance imaging (fMRI) time series can generate meaningful activation maps and associated descriptive signals, which are useful to evaluate datasets of the entire brain or selected portions of it. Besides computational implications, variations in the input dataset combined with the multivariate nature of ICA may lead to different spatial or temporal readouts of brain activation phenomena. By reducing and increasing a volume of interest (VOI), we applied sICA to different datasets from real activation experiments with multislice acquisition and single or multiple sensory-motor task-induced blood oxygenation level-dependent (BOLD) signal sources with different spatial and temporal structure. Using receiver operating characteristics (ROC) methodology for accuracy evaluation and multiple regression analysis as benchmark, we compared sICA decompositions of reduced and increased VOI fMRI time-series containing auditory, motor and hemifield visual activation occurring separately or simultaneously in time. Both approaches yielded valid results; however, the results of the increased VOI approach were spatially more accurate compared to the results of the decreased VOI approach. This is consistent with the capability of sICA to take advantage of extended samples of statistical observations and suggests that sICA is more powerful with extended rather than reduced VOI datasets to delineate brain activity.
Resumo:
With its invariant cell lineage, easy genetics and small genome, the nematode Caenorhabditis elegans has emerged as one of the prime models in developmental biology over the last 50 years. Surprisingly however, until a decade ago very little was known about nuclear organization in worms, even though it is an ideal model system to explore the link between nuclear organization and cell fate determination. Here, we review the latest findings that exploit the repertoire of genetic tools developed in worms, leading to the identification of important sequences and signals governing the changes in chromatin tridimensional architecture. We also highlight parallels and differences to other model systems.
Resumo:
In order to analyze software systems, it is necessary to model them. Static software models are commonly imported by parsing source code and related data. Unfortunately, building custom parsers for most programming languages is a non-trivial endeavour. This poses a major bottleneck for analyzing software systems programmed in languages for which importers do not already exist. Luckily, initial software models do not require detailed parsers, so it is possible to start analysis with a coarse-grained importer, which is then gradually refined. In this paper we propose an approach to "agile modeling" that exploits island grammars to extract initial coarse-grained models, parser combinators to enable gradual refinement of model importers, and various heuristics to recognize language structure, keywords and other language artifacts.
Resumo:
Im vorliegenden Beitrag wird aus Perspektive der strukturell-individualistischen Handlungstheorie versucht, kriminelles Handeln als soziales Handeln zu modellieren. Die subjektiv rationale Entscheidung für oder gegen delinquentes Handeln erfolgt in Abhängigkeit von Restriktionen, Gelegenheiten, Assoziationen sowie von normativen Überzeugungen und moralischen Bewertungen von Straftaten. Die empirische Anwendung mithilfe einer Bevölkerungsumfrage in Bern liefert für intendierte Straftaten wie Ladendiebstahl, Schwarzfahren, Versicherungsbetrug und Steuerhinterziehung theoriekonsistente Ergebnisse.
Resumo:
The three articles that comprise this dissertation describe how small area estimation and geographic information systems (GIS) technologies can be integrated to provide useful information about the number of uninsured and where they are located. Comprehensive data about the numbers and characteristics of the uninsured are typically only available from surveys. Utilization and administrative data are poor proxies from which to develop this information. Those who cannot access services are unlikely to be fully captured, either by health care provider utilization data or by state and local administrative data. In the absence of direct measures, a well-developed estimation of the local uninsured count or rate can prove valuable when assessing the unmet health service needs of this population. However, the fact that these are “estimates” increases the chances that results will be rejected or, at best, treated with suspicion. The visual impact and spatial analysis capabilities afforded by geographic information systems (GIS) technology can strengthen the likelihood of acceptance of area estimates by those most likely to benefit from the information, including health planners and policy makers. ^ The first article describes how uninsured estimates are currently being performed in the Houston metropolitan region. It details the synthetic model used to calculate numbers and percentages of uninsured, and how the resulting estimates are integrated into a GIS. The second article compares the estimation method of the first article with one currently used by the Texas State Data Center to estimate numbers of uninsured for all Texas counties. Estimates are developed for census tracts in Harris County, using both models with the same data sets. The results are statistically compared. The third article describes a new, revised synthetic method that is being tested to provide uninsured estimates at sub-county levels for eight counties in the Houston metropolitan area. It is being designed to replicate the same categorical results provided by a current U.S. Census Bureau estimation method. The estimates calculated by this revised model are compared to the most recent U.S. Census Bureau estimates, using the same areas and population categories. ^
Resumo:
Grandparents, particularly, grandmothers in the African American community have historically provided needed care for their grandchildren (Crewe, 2003). Before there was a child welfare system that addressed the needs of African American children, there were grandmothers who served as the safety net for their biological, informally adopted grandchildren, and other minor relatives. They cared for grandchildren and others whose birth parents were unable or unwilling to care for them. For families of color, HIV/AIDS is an emerging issue that is contributing to the growing numbers of grandparent-headed households. And once again, many African American grandmothers have accepted the challenge of holding their families together. This article addresses the HIV/AIDS public health challenge in the African American community with specific focus on its impact on older grandparents responsible for raising children of infected biological parents. It advocates for a model that continues to strengthen the Children’s Bureau investment in kinship care through integrating the needs of children and their aging caregivers.
Funciones de volumen para especies de bosque secundario de la Reserva Guaraní : Misiones (Argentina)
Resumo:
Se ajustaron y evaluaron funciones de volumen de fuste para un grupo de especies arbóreas de un bosque secundario. El bosque del cual se obtuvieron los datos se encuentra situado en la Reserva de Biosfera Yabotí, en la provincia de Misiones, Argentina. Se trabajó sobre una muestra de 216 árboles, correspondientes a las 14 especies presentes más importantes respecto de la estructura del bosque y/o del valor económico de las mismas. De las nueve funciones evaluadas, cinco de ellas tuvieron coeficientes de determinación ajustados superiores a 0,99. Por su destacado comportamiento estadístico global se seleccionó una expresión resultante de modificar el modelo de Naslund. Utilizando los resultados de esta función se construyó una tabla de volumen de fustes individuales en la cual el diámetro a 1,3 m de altura (D) y la altura de fuste (H) fueron las variables de entrada para árboles de un bosque secundario de aproximadamente 30 años de edad. Los D observados fueron desde 5,4 hasta 42 cm y el rango de H entre 1,4 y 16 m. Los modelos seleccionados dieron resultados satisfactorios para predecir volúmenes y cantidad de biomasa acumulada en los fustes de árboles del bosque secundario analizado en este trabajo.
Resumo:
El modelo U.S.L.E. (Universal Soil Loss Equation), desarrollado por Wischmeier y Smith en 1978, es un modelo paramétrico creado para estimar la pérdida anual de suelo. Engloba, dentro de los cinco factores intervinientes, todas las características de la cuenca, incluyendo tanto aspectos físicos como características edáficas, geológicas y geomorfológicas, sin olvidar las relacionadas con el clima, y el tipo de manejo y uso del suelo. El objetivo del trabajo fue estimar la pérdida de suelo a nivel de la cuenca hidrográfica del Arroyo Belisario, ubicada en el Partido de Tornquist, en el Sudoeste de la Provincia de Buenos Aires. Más de 1.200 ha (aproximadamente 50% de la cuenca), presentaron pérdidas de suelo mayores a las 50 tn.ha-1.año-1. Se observó que los factores K y LS son determinantes de los elevados valores presentes en la cabecera de la cuenca. La elaboración de la cartografía correspondiente a cada factor de la U.S.L.E se realizó con el Sistema de Información Geográfica Idrisi Andes. Se concluye que el modelo fue aplicado de manera correcta en la cuenca del Arroyo Belisario, brindando resultados que facilitarán la toma de decisiones para un futuro ordenamiento territorial.
Resumo:
El artículo se centra en el estado incipiente del soporte teórico de la educación dada en entornos digitales. Con fines de contribuir con el desarrollo de dicho soporte, ofrece un modelo conceptual fundamentado en un enfoque constructivista sociocultural, como referente para el diseño, la evaluación y la investigación en el campo particular de la educación digital. El modelo es resultado de la ampliación justificada del triángulo interactivo propuesto por Coll (1996; 2004) para el análisis de las actividades educativas. Está constituido por cuatro grupos de factores: del contenido, del estudiante, del docente y de las condiciones técnico-ambientales del programa, permitiendo abordar sistemáticamente las particularidades de las actividades educativas dadas en entornos digitales. Sustentado en fuentes actualizadas, el artículo presenta y describe los factores más relevantes de cada grupo.
Resumo:
El artículo se centra en el estado incipiente del soporte teórico de la educación dada en entornos digitales. Con fines de contribuir con el desarrollo de dicho soporte, ofrece un modelo conceptual fundamentado en un enfoque constructivista sociocultural, como referente para el diseño, la evaluación y la investigación en el campo particular de la educación digital. El modelo es resultado de la ampliación justificada del triángulo interactivo propuesto por Coll (1996; 2004) para el análisis de las actividades educativas. Está constituido por cuatro grupos de factores: del contenido, del estudiante, del docente y de las condiciones técnico-ambientales del programa, permitiendo abordar sistemáticamente las particularidades de las actividades educativas dadas en entornos digitales. Sustentado en fuentes actualizadas, el artículo presenta y describe los factores más relevantes de cada grupo.
Resumo:
El artículo se centra en el estado incipiente del soporte teórico de la educación dada en entornos digitales. Con fines de contribuir con el desarrollo de dicho soporte, ofrece un modelo conceptual fundamentado en un enfoque constructivista sociocultural, como referente para el diseño, la evaluación y la investigación en el campo particular de la educación digital. El modelo es resultado de la ampliación justificada del triángulo interactivo propuesto por Coll (1996; 2004) para el análisis de las actividades educativas. Está constituido por cuatro grupos de factores: del contenido, del estudiante, del docente y de las condiciones técnico-ambientales del programa, permitiendo abordar sistemáticamente las particularidades de las actividades educativas dadas en entornos digitales. Sustentado en fuentes actualizadas, el artículo presenta y describe los factores más relevantes de cada grupo.