5,154 research outputs found
Automatic segmentation of exudates in colour retinal fundus images
This work aims at the development of an algorithm that allows the automatic detection of exudates in retinal fundus images. The detection of exudates allows diabetic retinopathy (DR) to be diagnosed, consequently it is an important task for the control and the treatment of people suffering DR. In addition, an increase of 35\% of people suffering from diabetes is predicted and, therefore, of people who will suffer from DR in the coming years. As a result, an important burden for ophthalmologists will be expected. For all this, it's highly needed the development of an automatic system for the detection of exudates. Two different algorithms are proposed. Background subtraction to deal with uneven illumination and mathematical morphology operators are used for exudate location. Finally, dynamic thresholding is applied for exudate segmentation. In the first algorithm dynamic thresholding is combined with the Kirsch edge detector. In the second one, a template and morphological operators are used to differentiate bright elements from exudates is used. The methods have been validated in three public datasets named e-ophta-EX, HEI-MED and DiaretDB1. The first two datasets have been used to validated the algorithms both at lesion level and image-level. However, DiaretDB1 was only used to validate the algorithms at image-level due to its ground truth does not mark exact boundaries of exudates. The results for the image-level validation are better for the second algorithm obtaining an AUC of 0.84, 0.75 and 0.84 for e-ophta-EX, HEI-MED and DiaretDB1, respectively. The results obtained with the evaluation at lesion-level are the same for the two methods and are quantified in terms of sensitivity and PPV. We have achieved values of sensitivity and PPV of 0.54 and 0.52, respectively, in e-ophta-EX and, 0.52 and 0.52, respectively, in HEI-MED for method 1. For method 2, we have obtained values for sensitivity and PPV of 0.5 and 0.57, respectively, for e-ophta-EX and 0.42 and 0.76, respectively, for HEI-MED.Outgoin
Towards a Shared Control Navigation Function:Efficiency Based Command Modulation
This paper presents a novel shared control algorithm for robotized
wheelchairs. The proposed algorithm is a new method to extend
autonomous navigation techniques into the shared control domain. It reactively
combines user’s and robot’s commands into a continuous function
that approximates a classic Navigation Function (NF) by weighting input
commands with NF constraints. Our approach overcomes the main drawbacks
of NFs -calculus complexity and limitations on environment
modeling- so it can be used in dynamic unstructured environments. It also
benefits from NF properties: convergence to destination, smooth paths
and safe navigation. Due to the user’s contribution to control, our function
is not strictly a NF, so we call it a pseudo-navigation function (PNF)
instead.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
CHARACTERIZATION OF CLAYS USED FOR MEDICINAL PURPOSES IN THE ARCHIPELAGO OF CAPE VERDE
Amostras de duas argilas comercializadas para fins medicinais (alívio de afecções do
foro gastrointestinal, tratamento de abcessos, furúnculos e feridas, assim como para
afecções da pele e aplicações cosméticas), e vendidas numa loja de produtos naturais no
mercado público da cidade da Praia (capital do arquipélago de Cabo Verde) foram
submetidas a vários estudos de carácter experimental: análise granulométrica, análise
mineralógica, análise química, capacidade de troca catiónica e catiões de troca, e ainda
plasticidade, tendo em vista encontrar justificação científica para o seu uso empírico nas
aplicações referidas. Uma argila, em termos de minerais argilosos, é composta por ilite
dioctaédrica, enquanto que outra argila é composta, em termos de minerais argilosos, por
esmectite dioctaédrica, ilite dioctaédrica e caulinite. Estes e os outros dados analíticos
abonam a favor das capacidades curativas das argilas estudadas. As argilas estudadas
revelam características semelhantes às de outras argilas naturais reconhecidas como
possuindo propriedades curativas de certas afecções e que são tradicionalmente usadas
para desintoxicação interna (particularmente no sistema gastrointestinal), para o tratamentoResearch Centre “GeoBioTec” of the Foundation for Science and Technology (FCT), Instituto Nacional de Investigação Agrária (INIA)
Nano-technological products in architecture and construction
This work presents a review of the scientific literature that deals with the use of nanoscience and nanotechnology in architecture and construction industry in view of letting architects, builders, real estate promoters and interested parties know the scope that various nanomaterials, existing in the construction market could be used in this activities every-day from a sustainable and durable approach to architecture and construction. As a result we present, in an orderly and classified manner, a list of nano-products that can be applied to architecture and construction in building structures, covers and installations with an approach based on the architectonic and constructive durability of each component. It is concluded that there are numerous nano-products with different uses and applications sufficient for some construction needs, with important applications such as: improvement of the durability and degradation of materials (mainly concrete and steel), the efficiency of equipment and devices such as batteries, photovoltaic cells, electrical conductors, OLED lamps, water filters, paints, sealants, windowpanes, electronical components, architectural finishes, among other products
ANÁLISIS DE DESEMPLEO JUVENIL EN LA REPÚBLICA MEXICANA EN EL PERIODO 2005-2015
Es importante invertir en la creación de empleo para los jóvenes ya que recientes
estudios indican que el empleo juvenil incide en cada aspecto del crecimiento y el
desarrollo de un país. De acuerdo con las Tendencias Mundiales del Empleo Juvenil
2015, “una juventud feliz es aquella que vislumbra perspectivas emocionantes para el
futuro. Cuanto mejor conduzcamos la juventud hacia el empleo productivo, mejor
nuestras esperanzas de impulsar el espíritu positivo de la gente joven y progresar hacia
un marco general de desarrollo inclusivo” (OIT).
Para que México sea capaz de crear alternativas para que los jóvenes tengan acceso a
más y mejores empleos es necesario realizar un análisis de la situación que el mercado
laboral mexicano ha enfrentado en los últimos años, tomando en cuenta la tasa de
desempleo y la manera en que otras variables la afectan como la educación, la
experiencia laboral, la duración del desempleo, la esperanza de vida y el PIB per cápita.
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La investigación está dividida en seis capítulos, el primero hace referencia a esta
introducción. En el segundo capítulo se describen los conceptos básicos sobre el
mercado de trabajo, así como los dos modelos principales para explicar su
funcionamiento, el modelo clásico y el modelo keynesiano. Además se describen dos
teorías modernas del desempleo, la de búsqueda laboral y la de contratos implícitos
que ayudan a entender el desarrollo del desempleo en la actualidad.
En el capítulo tres se realiza una descripción cuantitativa dentro del periodo de estudio
acerca del desempleo tanto a nivel mundial como en México, además se da un
panorama de como la crisis económica mundial de 2008 intervino en el aumento de
éste, principalmente en el desempleo juvenil. Finalmente se muestran estadísticas y
gráficas de los niveles de desempleo que existen en las entidades federativas de la
República Mexicana en el periodo estudiado.ESTA TESIS ES PARTE DE LA INVESTIGACIÓN DESEMPLEO JUVENIL POR
ENTIDAD FEDERATIVA 2005-2013 CON CLAVE 3799/2014/CI, FINANCIADA POR LA
UNIVERSIDAD AUTÓNOMA DEL ESTADO DE MÉXICO, PERTENECIENTE AL
CUERPO ACADÉMICO, DESARROLLO ECONÓMICO, SOCIAL Y REGIONAL, UAEMCA-4
Parents Acquiring Learning Strategies (PALS): How Empowering Hispanic Parents Increases Parental Involvement and Student Achievement
Some Hispanic parents in Miami-Dade County show limited involvement in the educational process of their children. Currently, Miami-Dade County Public schools consists of an increasingly high number of language minority students who come from homes where parents are limited in their English proficiency. Consequently, these parents have difficulty assisting their children with schoolwork and often feel they lack adequate skills to involve themselves in school curricula. The lack of parental involvement by this population has a negative impact on students’ learning and their academic achievement. The purpose of this study is to impact the level of participation of these families and to study its ultimate effect on students’ academic achievement
Relevance of the study of metabolic profiles in sheep and goat flock. Present and future: A review
Current adoption of technical methods of the production systems and the genetic improvement of flocks’ productivity have led to the emergence of the well-known metabolic diseases or diseases linked to production. These disorders affect the health status of the flock, thereby generating strong economic losses in the livestock sector. The solution goes through the assessment of the ration, the characteristics of the facilities, the physiological state and the health of the flock, but also, assessing the health condition which is not always reflected in their body condition or feed intake. In field conditions, metabolic profiles could be considered as possible intermediate monitoring tool between animal production and nutrition, because they are able to express a(n) (im)balance between production requirements and feed intake. This information can be accessed by performing measurements and interpreting different blood parameters in a clinical context. Thus, the aim of this review is to offer current information about biochemical metabolic parameters in small ruminants, covering some influencing aspects related to sampling procedure, management and interpretation of results
X-Ray Fluorescence Analysis of Ground Coffee
Coffee is becoming one of the most popular beverages in Mexico. In the present work, X-ray Fluorescence (XRF) was used to determine the contents of several elements (with atomic numbers between 11 and 38) in 11 samples of commercial ground coffee, comparing with another one of soluble coffee and two of used ground coffee. Samples were dried at room temperature and pelletized. XRF analyses were carried out using a spectrometer based on an Rh X-ray tube, registering the characteristic x-rays with a Silicon Drift Detector. The system detection calibration and accuracy check was performed through the analysis of NIST certified reference materials 1547 (peach leaves), 1570a (spinach leaves), 1573a (tomato leaves), and 1571 (orchid leaves). As a general rule, the elemental concentrations measured are similar in all samples of coffee, in values not exceeding toxic levels. However, the differences among the elemental concentrations are shown
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