Practical verification strategy for refinement conditions in UML models

This paper presents an automatic and simple method for creating refinement condition for UML models. Conditions are fully written in OCL, making it unnecessary the application of mathematical languages which are in general hardly accepted to software engineers. Besides, considering that the state space where OCL conditions are evaluated might be too large (or even infinite), the strategy of micromodels is applied in order to reduce the search space. The overall contribution is to propitiate the performing of verification activities during the model-driven development process.1st International Workshop on Advanced Software Engineering: Expanding the Frontiers of Software Technology - Session 2: Software ModelingRed de Universidades con Carreras en Informática (RedUNCI

Practical verification strategy for refinement conditions in UML models

This paper presents an automatic and simple method for creating refinement condition for UML models. Conditions are fully written in OCL, making it unnecessary the application of mathematical languages which are in general hardly accepted to software engineers. Besides, considering that the state space where OCL conditions are evaluated might be too large (or even infinite), the strategy of micromodels is applied in order to reduce the search space. The overall contribution is to propitiate the performing of verification activities during the model-driven development process.1st International Workshop on Advanced Software Engineering: Expanding the Frontiers of Software Technology - Session 2: Software ModelingRed de Universidades con Carreras en Informática (RedUNCI

A Lightweight Approach for the Semantic Validation of Model Refinements

Model Driven Engineering proposes the use of models at different levels of abstraction. Step by step validation of model refinements is necessary to guarantee the correctness of the final product with respect to its initial models. But, given that accurate validation activities require the application of formal modeling languages with a complex syntax and semantics and need to use complex formal analysis tools, they are rarely used in practice. In this article we describe a lightweight validation approach that does not require the use of third-party (formal) languages. The approach makes use of the standard OCL as the only visible formalism, so that refinements can be checked by using tools that are fully understood by the MDE community. Additionally, for the efficient evaluation of the refinement conditions a hybrid strategy that combines model checking, testing and theorem proving is implemented. Correctness and complexity of the proposal are empirically validated by means of the development of case studies and a comparison with the Alloy analyzer.Laboratorio de Investigación y Formación en Informática Avanzad

A Lightweight Approach for the Semantic Validation of Model Refinements

Model Driven Engineering proposes the use of models at different levels of abstraction. Step by step validation of model refinements is necessary to guarantee the correctness of the final product with respect to its initial models. But, given that accurate validation activities require the application of formal modeling languages with a complex syntax and semantics and need to use complex formal analysis tools, they are rarely used in practice. In this article we describe a lightweight validation approach that does not require the use of third-party (formal) languages. The approach makes use of the standard OCL as the only visible formalism, so that refinements can be checked by using tools that are fully understood by the MDE community. Additionally, for the efficient evaluation of the refinement conditions a hybrid strategy that combines model checking, testing and theorem proving is implemented. Correctness and complexity of the proposal are empirically validated by means of the development of case studies and a comparison with the Alloy analyzer.Laboratorio de Investigación y Formación en Informática Avanzad

Exploring Historical Coffee and Climate Relations in Southern Guatemala: An Integration of Tree Ring Analysis and Remote Sensing Data

This dissertation makes use of a physical geography perspective to examine the relationship between agriculture and climate in Guatemala using dendrochronology. I examined the potential of high-resolution climate proxy data from dendrochronology to help fill in the gaps of past climate information to better understand the natural and anthropogenic variability of precipitation which, in turn, can inform Guatemala’s agriculture sector. This research has demonstrated successful cross-dating and climate sensitivity of Abies guatemalensis in the Pacific slope of Guatemala. Based on this, I have produced a 124-year record of mean precipitation from June-July-August. The mean precipitation from June-July-August at this site seems to receive an important influence from the sea surface temperature (SST) in the Pacific Ocean in the form of El Niño Southern Oscillation (ENSO) in the region 3.4. The analysis on the frequency of the precipitation records suggests that single year droughts dominate the record yet, periods of 9 years below-average rainfall can persist. Likewise, single year pluvial events also dominate the evaluated period. The long-term reconstruction of precipitation allowed to describe past relationships between coffee plantations and pests. For instance, the frequency analysis suggests that 4 or more consecutive periods of above-average precipitation are associated with several coffee pests and subsequently great economical losses due to crop failures, including the last coffee leaf rust crisis. This study also presents a streamflow reconstruction of the Upper Samalá River watershed using a tree ring-width chronology derived from the Guatemalan fir (Abies guatemalensis) to reconstruct mean August-September-October streamflow volumes for the period 1889-2013. Our analysis shows that strong statistical correlations are present between tree-ring width measurements and monthly natural streamflow series. The mean August-September-October streamflow variability is dominated by single year events for both above and below the long-term mean. This reconstruction reveals important teleconnections with the ENSO 3.4 region and it is to our knowledge, the only streamflow reconstruction in Guatemala using tree-ring measurements. This new long-term record will be useful to recalculate historical discharge peaks and floods that affect agricultural areas in the mid and lower basin but also the hydroelectric production. Our analysis suggests that records from the GIMMS 3g v.0 Normalized Difference Vegetation Index (NDVI), are inversely correlated to precipitation in the Upper Samalá River watershed at the location of the A. guatemalensis forest stand Kanchej. This suggest that the net solar radiation income during the cloud-free timing throughout the mid-summer drought could be partially responsible for promoting cloudiness by heating the SST and hence, promoting precipitation during the second peak of precipitation during September and October. The independent analyses of precipitation and NDVI sensitivity of A. guatemalensis and the correlation between precipitation and NDVI suggest that precipitation is a modulator of radial growth of A. guatemalensis in this location of Guatemala. These findings can be used to refine the knowledge on the climatic controls on A. guatemalensis radial growth

Estudio de la Asociación entre Desastres Naturales por Inundación y Eventos Epidémicos

La presente tesis analiza la ocurrencia de brotes epidémicos y su relacion causal con eventos de inundación en Argentina durante el periodo 2005 a 2007. Mediante el uso de informacion metereologica y epidemiológica, se analizaron la relación entre los diferentes descriptores de las inundaciones, y su relacion con la ocurrencia, numero y tipo de brotes epidémicos. Asimismo, se caracterizaron las condiciones ambientales por tipo de epidemia y factor ambiental. Mediante el uso de modelos lineales generalizados mixtos, se analizó la ocurrencia de casos por enfermedad y su relación con factores ambientales, observándose relaciones significativas como vegetación (NDVI), lluvias acumuladas semanalmente, lluvias máximas y temperaturas medias, máximas y mínimas. Se analizo en particular un brote epidémico de malaria Iguazú durante el año 2007, generándose un mapa de distribución potencial del vector y áreas más riesgosas, basado en la biología del vector, humedad de suelo, tipos de cobertura del suelo y cercanía a cuerpos de agua. Para la determinación de humedad de suelo se utilizaron imágenes SAR (ALOS Palsar) y modelos inversos. Finalmente se sugirieron productos de potencial uso para la gestión de epidemias postinundación, provistos por la red GeoNet Cast Americas, relacionados con estado de la vegetación y variables climáticas

Contribution of agroforestry systems to sustaining biodiversity in fragmented forest landscapes

Agroforestry systems maintain intermediate levels of biodiversity between natural forests and purely agricultural land-uses and may therefore increase connectivity or sustain biodiversity in fragmented forest landscapes. This hypothesis is tested by comparing the species richness and similarity in species composition between forest fragments and agroforestry systems in two landscapes in Guatemala. Connectivity indices were calculated based on the similarity of biodiversity held between forest and agroforestry. Tree and ant species richness was significantly higher for forest than agroforestry land-uses. Conversely, species richness of leaf hoppers (Cicadellidae) was lower in forests compared to agroforests. Chao-Sorensen estimates indicated a high proportion of ant species were shared (0.78-0.99) between different agroforestry land-uses and forest fragments, but lower proportions of tree (0.39 – 0.55) and leaf hopper species (0.42-0.65). Including the contribution of agroforestry systems in estimates of forest connectivity, based on their biodiversity relative to forest, substantially increased the land area rated with high connectivity (by 100-300%) and forest edge connectivity (by 70-170%), but had negligible impact on land area rated as dense forest. The major forest fragments in the two landscapes were linked by land rated as medium connectivity for forest biodiversity. Thus, agroforestry contributes to the capacity of the landscape to support biodiversity, but only partially increases connectivity between forest fragments in the two landscapes studied. If these benefits are to be sustained, consideration needs to be given to the incentives for land-owners to maintain agroforestry systems

Evaluación de algoritmos de clasificación supervisada en plataformas web de la nube (Google Earth Engine) aplicado al mapeo de coberturas forrajeras

El objetivo de este trabajo fue experimentar el uso d dos algoritmos y evaluar su desempeño como herramientas para clasificar coberturas de vegetación, particularmente forrajeras, en el valle de Traslasierra, de la provincia de Córdoba, Argentina. SVM y RF, fueron seleccionados entre los algoritmos de clasificación disponibles en la interfaz de la aplicación de programación del Google Earth Engine (GEE).Sociedad Argentina de Informática e Investigación Operativa (SADIO

Identification of environmental buffer areas in urbanized catchments based on synthetic ecosystem functions

The Saldan river basin in the northwest of the metropolitan area of Córdoba, Argentina, was defined as a unit for the observation of ecosystem services of water regulation. The capacity of the system to retain excess rainfall through vegetation in areas with slopes was analyzed. The observation area was a wildland-urban interface. From there, a model capable of synthesizing the behavior of the most relevant variables in the event of an extraordinary rainfall event was adjusted. The result was the definition of buffer areas or exosystemic protection in the interface. The testing and adjustment of this model defined a REP indicator that was proposed as an input in the planning of the sector. For validation, soil moisture permanence values from LWI were used. The derivative was calculated for each pixel value in the basin, for both dry and wet periods, and the areas with the lowest loss in both periods were compared with those with the highest retention obtained in the model. The zones identified by both methods show great similarities.Fil: Céliz, Yuliana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Agencia de Extension Rural Villa Maria (aer Villa Maria) ; Estacion Experimental Agropecuaria Manfredi ; Centro Regional Cordoba ; Instituto Nacional de Tecnologia Agropecuaria; . Universidad Nacional de Córdoba. Facultad de Arquitectura, Urbanismo y Diseño; ArgentinaFil: Pons, Diego Hernan. Agencia de Extension Rural Villa Maria (aer Villa Maria) ; Estacion Experimental Agropecuaria Manfredi ; Centro Regional Cordoba ; Instituto Nacional de Tecnologia Agropecuaria; . Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Giobellina, Beatriz. Observatory of Periurban Urban Agriculture and Agroecology; Argentina. Universidad Nacional de Córdoba. Facultad de Arquitectura, Urbanismo y Diseño; Argentina. Universidad Nacional de Córdoba; ArgentinaFil: Zefferino, Marcos. Universidad Tecnológica; Urugua

Controlling ligand surface density on streptavidin-magnetic particles by a simple, rapid, and reliable chemiluminescent test

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