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The dynamic reconfiguration and maximum power point tracking in large-scale photovoltaic (PV) systems require a large number of voltage and current sensors. In particular, the reconfiguration process requires a pair of voltage/current sensors for each panel, which introduces costs, increases size and reduces reliability of the installation. A suitable solutions for reducing the number of sensors is to adopt image-based solution to estimate the electrical characteristics of the PV panels, but the lack of reliable data with large diversity of irradiance and shading conditions is a major problem in this topic. Therefore, this paper presents dataset correlating RGB images and electrical data of PV panels with different irradiance and shading conditions. The dataset was designed to support the design of image-based estimators of electrical data, which could be used to replace large arrays of sensors. The paper also describes the measurement platform used to collect the data, which helps to replicate the experiments in different geographical locations.

A total of 256 surveys were analyzed for Caquetá and 227 surveys forYurimaguas. These surveys belong to the project "Sustainable Amazonian Landcapes" ( see below Related Datasets). All the households that participated in the survey did it freely and under prior informed consent. Households were asked about their farms’ agrobiodiversity (crops, cattle ranching, and pastoral diversity), farming activities, agroecological management practices and livelihood assets. These surveys provided the information required for defining the household typologies based on farming livelihood diversification and to obtain indicators of vulnerability to climate change. People surveyed usually were household heads or their spouses. The supervisors were the direct link with CIAT. The data was collected through Android Devices using the software CsPro 6.2 and 6.3. (Reporte Interno)

Agricultural adaptation to climate change is critical for ensuring future food security. Social capital is important for climate change adaptation, but institutions and social networks at multiple scales (e.g., household, community, and institution) have been overlooked in studying agricultural climate change adaptation. We combine data from 13 sites in 11 low-income countries in East Africa, West Africa, and South Asia to explore how multiple scales of social capital relate to household food security outcomes among smallholder farmers. Using social network theory, we define three community organizational social network types (fragmented defined by lack of coordination, brokered defined as having a strong central actor, or shared defined by high coordination) and examine household social capital through group memberships. We find community and household social capital are positively related, with higher household group membership more likely in brokered and shared networks. Household group membership is associated with more than a 10% reduction in average months of food insecurity, an effect moderated by community social network type. In communities with fragmented and shared organizational networks, additional household group memberships is associated with consistent decreases in food insecurity, in some cases up to two months; whereas in brokered networks, reductions in food insecurity are only associated with membership in credit groups. These effects are confirmed by hierarchical random effects models, which control for demographic factors. This suggests that multiple scales of social capital—both within and outside the household—are correlated with household food security. This social capital may both be bridging (across groups) and bonding (within groups) with different implications for how social capital structure affects food security. Efforts to improve food security could recognize the potential for both household and community level social networks and collaboration, which further research can capture by analyzing multiple scales of social capital data.

In the Socotá area in Boyacá, Colombia, high contents of coalbed methane have been reported. In order to prove it, additional gas measurements were done and different possibilities of degassing were considered. To measure the gas content, the canisters desorption system were used, with control of pressure and temperature, according to the USBM and GRI methodology. Lost, desorbed and residual gases were determined separately, and proximate analyses were also carried out. In some samples the content of gas reached the 100-200 SCF/t. These gas contents have good possibilities for energy production (CBM) by drilling vertical wells to extract it.Those wells would not only produce gas, but would also degas the future underground mining areas. The combination of degasification and ventilation would considerably allow a decrease in the explosions risk. The high coalbed methane content in the area could produce energy for the mining company or commercial gas for the natural gas distribution network. The Socotá area has the ideal conditions for a pilot project, which could be a model for other degasification projects in Colombia.

Este artículo presenta el estado actual de las técnicas de inteligencia artificial y su aplicación al campo de la detección y diagnóstico de fallas en sistemas dinámicos. Inicialmente, se hace una breve descripción de lo que se considera un mecanismo de detección y diagnóstico de fallas, y se explican los enfoques actuales de estudio y aplicación de tales mecanismos. Posteriormente, se presentan los resultados más importantes de las diferentes técnicas de inteligencia artificial aplicadas a la detección y diagnóstico de fallas. Finalmente, se presenta un análisis comparativo con base en las características deseables de los mecanismos de detección y diagnóstico de fallas. El artículo concluye mencionando los beneficios de la clasificación de las técnicas presentadas y enumerando las posibles vías hacia donde debe ir la investigación en este campo.

Abstract. An improved understanding of present-day climate variability and change relies on high-quality data sets from the past 2 millennia. Global efforts to model regional climate modes are in the process of being validated against, and integrated with, records of past vegetation change. For South America, however, the full potential of vegetation records for evaluating and improving climate models has hitherto not been sufficiently acknowledged due to an absence of information on the spatial and temporal coverage of study sites. This paper therefore serves as a guide to high-quality pollen records that capture environmental variability during the last 2 millennia. We identify 60 vegetation (pollen) records from across South America which satisfy geochronological requirements set out for climate modelling, and we discuss their sensitivity to the spatial signature of climate modes throughout the continent. Diverse patterns of vegetation response to climate change are observed, with more similar patterns of change in the lowlands and varying intensity and direction of responses in the highlands. Pollen records display local-scale responses to climate modes; thus, it is necessary to understand how vegetation–climate interactions might diverge under variable settings. We provide a qualitative translation from pollen metrics to climate variables. Additionally, pollen is an excellent indicator of human impact through time. We discuss evidence for human land use in pollen records and provide an overview considered useful for archaeological hypothesis testing and important in distinguishing natural from anthropogenically driven vegetation change. We stress the need for the palynological community to be more familiar with climate variability patterns to correctly attribute the potential causes of observed vegetation dynamics. This manuscript forms part of the wider LOng-Term multi-proxy climate REconstructions and Dynamics in South America – 2k initiative that provides the ideal framework for the integration of the various palaeoclimatic subdisciplines and palaeo-science, thereby jump-starting and fostering multidisciplinary research into environmental change on centennial and millennial timescales.

Los sistemas de agricultura del departamento del Chocó, están ligados a valores culturales y sociales, donde la finalidad de la producción es primordialmente el autoconsumo. El proceso productivo se basa en el uso de la tierra y el trabajo familiar. [1] La zona del pacífico presenta gran biodiversidad y un número amplio de frutas de interés agroindustrial que podrían ser racionalmente explotadas con fines productivos y ponerlas en el mercado internacional posicionando la zona como productora de frutas promisorias tales como el borojó y el chontaduro, las cuales se pierden por falta de uso a gran escala. [1] Con este trabajo se pretende incentivar al desarrollo de la industria oleo química para obtener productos de mayor valor agregado que contribuya al auto-sostenimiento a nivel energético de las regiones en este caso del Pacífico colombiano. En esta investigación se estudió la producción y caracterización de alquil ésteres de aceite crudo de Bactris gasipaes (chontaduro) realizando la reacción de transesterificación con metanol y catalizadores homogéneos y heterogéneos, optimizando los parámetros de síntesis y comparando el rendimiento en la producción de biodiesel en las dos metodologías. En la primera parte del trabajo (capítulo 3), se evaluó dos métodos de extracción del aceite de chontaduro: extracción mediante cocción del fruto y extracción con solventes (soxhlet). Las variables estudiadas son: tiempo, temperatura y relación solvente: fruto, optimizando la producción mediante la metodología de superficie de respuesta. El aceite obtenido se sometió a un proceso de desgomado para refinarlo y caracterizado mediante pruebas como: índice de acidez (ASTM D664), índice de yodo (ASTM D-5554), índice de saponificación (ASTM D-5558) e índice de humedad (ASTM D-2216). En el capítulo 4, se estudió la producción de biodiesel de chontaduro mediante catálisis homogénea (metanol-hidróxido de potasio) y catálisis heterogénea (metanol-catalizador de potasio soportado en TiO2), empleando aceite crudo y desgomado. Las ...