Agricolae - Ten years of an open source statistical tool for experiments in breeding, agriculture and biology.

Plant breeders and educators working with the International Potato Center (CIP) needed freely available statistical tools. In response, we created first a set of scripts for specific tasks using the open source statistical software R. Based on this we eventually compiled the R package agricolae as it covered a niche. Here we describe for the first time its main functions in the form of an article. We also review its reception using download statistics, citation data, and feedback from a user survey. We highlight usage in our extended network of collaborators. The package has found applications beyond agriculture in fields like aquaculture, ecology, biodiversity, conservation biology and cancer research. In summary, the package agricolae is a well established statistical toolbox based on R with a broad range of applications in design and analyses of experiments also in the wider biological community

Evaluacion de la estabilidad de resistencia de clones avanzados del CIP a la marchitez bacteriana usando diferentes variantes de Ralstonia solanacearum.

La marchitez bacteriana (MB) o pudricion parda causada por Ralstonia solanacearum es una de las enfermedades bacterianas mas destructivas en el cultivo de la papa. La resistencia de las plantas es el medio mas efectivo para controlar esta enfermedad. Sin embargo, la resistencia a la MB es a menudo superada debido a la gran variabilidad del patogeno. En el presente trabajo se evaluo la reaccion de 10 clones avanzados del CIP (seleccionados previamente por su resistencia al BV2A) contra 5 cepas correspondientes a los biovares 1, 2a, 2T y 3, de R. solanacearum bajo condiciones de invernadero. 15 plantas por clon de aproximadamente 15 cm de altura fueron inoculadas vertiendo en el suelo una suspension de 150 ml de la bacteria para obtener una concentracion final de 10 7 ufc/g suelo. Las variedades de papa Revolucion y CIP -01149 fueron utilizadas como control susceptible y moderadamente resistente, respectivamente. Las evaluaciones de la presencia de los sintomas de marchitez se realizaron semanalmente hasta 10 dias antes de la cosecha de los tuberculos. En plantas sin sintomas, los tallos y tuberculos fueron analizados mediante ELISA-NCM post-enriquecimiento para detectar infeccion latente. El analisis estadistico del porcentaje de plantas infectadas muestra diferencias significativas entre clones y cepas de R. solanacearum. No se observo resistencia completa (0% de infeccion) en ninguno de los clones evaluados a todas las cepas -de R. solanacearum. Sin embargo, el clon 394895.7 fue el mas resistente, mostrando un maximo de 13 % de infeccion cuando fue inoculado con la cepa mas virulenta (CIP-204). La resistencia a todas las cepas de R. solanacearum detectada en el clon 394895.7 muestra su alto potencial como una fuentes genetica de la resistencia a la marchitez bacterian

Desarrollo de un Dashboard como herramienta de monitoreo para optimizar el sistema de aprovisionamiento de la Distribuidora Ferbanz S.A.C

El presente trabajo de investigación tuvo como principal objetivo desarrollar un Dashboard como herramienta de monitoreo para optimizar el sistema de reaprovisionamiento de la DISTRIBUIDORA FERBANZ S.A.C. Para el desarrollo, se obtuvo información de los datos de demanda de los últimos años, posteriormente después de evaluarlas con el coeficiente de variación se determinó, que el Modelo de revisión Continua o Modelo ""Q"" era el más propicio, al contar con una demanda variable y reaprovisionamiento siguiendo el patrón de punto de recompra, además se definió la política de inventarios para demanda variable, con tiempos de entrega constantes. Posteriormente se diseñó el código fuente basado exclusivamente en tecnologías web libres con licencia MIT, como Laravel para el backend, Jquery y Javascript nativo para el lado del cliente todo esto en sus últimas versiones, perfectas para el uso empresarial. Finalmente, se validó el sistema tomando en cuenta todos los procesos programados, revisando con los usuarios si se cumplían con las especificaciones de la empresaThe main objective of this research work was to develop a Dashboard as a monitoring tool to optimize the replenishment system of DISTRIBUIDORA FERBANZ S.A.C. For the development, information was obtained from the demand data of the last years, later after evaluating them with the coefficient of variation, it was determined that the Continuous Review Model or ""Q"" Model was the most favorable, having a demand variable and replenishment following the repurchase point pattern, in addition, the inventory policy for variable demand was defined, with constant delivery times. Subsequently, the source code was designed based exclusively on free web technologies with MIT license, such as Laravel for the backend, Jquery and native Javascript for the client side, all of this in its latest versions, perfect for business use. Finally, the system was validated taking into account all the programmed processes, checking with the users if they met the company's specificationsTesi

Thermodynamic study of syngas combustion in gas microturbines with regeneration composed with metallic and ceramic materials

The objective of this research is to carry out an energetic evaluation of syngas combustion in gas microturbines with regenerators made with two different types of material: metallic or ceramic. A modified chemical equilibrium model was used to calculate syngas composition obtained from sugarcane bagasse gasification in a fluidized bed gasifier using steam as gasifying agent. For the gas microturbines with a regenerator of metallic materials, combustion temperatures of 850, 900, and 950 °C were established; and for those with a regenerator of ceramic materials, combustion temperatures of 1150, 1250, and 1350 °C were established. The range for the compression ratio was 2 to 6, and the excess air percentages employed were 400, 500, and 600%. Excellent results were obtained: maximum power ratio was 1.87 kWh/Nm3, maximum cycle efficiency was 57%, and maximum regenerator effectiveness was 100%. Thus, syngas combustion performance in the gas microturbines with regeneration was excellent

Migrating Individuals and Probabilistic Models on DEDAS: a Comparison on Continuous Functions

One of the most promising areas in which probabilistic graphical models have shown an incipient activity is the field of heuristic optimization and, in particular, in the Estimation of Distribution Algorithms (EDAs). EDAs constitute a well-known family of Evolutionary Computation techniques, similar to Genetic Algorithms. Due to their inherent parallelism, different research lines have been studied trying to improve EDAs from the point of view of execution time and/or accuracy. Among these proposals, we focus on the so-called island-based models. This approach defines several islands (EDA instances) running independently and exchanging information with a given frequency. The information sent by the islands can be a set of individuals or a probabilistic model. This paper presents a comparative study of both information exchanging techniques for a univariate EDA (U M DAg) over a wide set of parameters and problems –the standard benchmark developed for the IEEE Workshop on Evolutionary Algorithms and other Metaheuristics for Continuous Optimization Problems of the ISDA 2009 Conference. The study concludes that the configurations based on migrating individuals obtain better result

On the evaluation of information exchange strategies in dEDAs

One of the most promising areas in which probabilistic graphical models have shown an incipient activity is the field of heuristic optimization and, in particular, in the Estimation of Distribution Algorithms (EDAs). EDAs constitute a well-known family of Evolutionary Computation techniques, similar to Genetic Algorithms. Due to their inherent parallelism, different research lines have tried to improve EDAs from the point of view of execution time and/or accuracy. Among these proposals, we focus on the so-called island-based models. This approach defines several islands (EDA instances) running independently and exchanging information with a given frequency. The information sent by the islands can be a set of individuals or a probabilistic model. This paper presents a comparative study of both information exchanging techniques for a univariate EDA (UMDAg) over a wide set of parameters and problems –the standard benchmark developed for the IEEE Workshop on Evolutionary Algorithms and other Metaheuristics for Continuous Optimization Problems of the ISDA 2009 Conference

Optimización de la conservación in vitro de germoplasma de Dioscorea spp por crecimiento mínimo

El ñame Criollo (Dioscorea alata) y el ñame Espino (Dioscorea rotundata) se constituyen como las dos especies mayormente cultivadas en el departamento de Sucre, Colombia. Por esta razón en la Universidad de Sucre se han implementado técnicas para lograr su conservación mediante la propagación in vitro, sin embargo esta metodología conserva las accesiones por un periodo no mayor a los 4 meses, provocando continuos subcultivos, aumento de costos y mano de obra. Por ello la presente investigación tuvo como objetivo establecer medios de cultivo óptimos para la conservación in vitro por crecimiento mínimo de diferentes accesiones (D. alata y D. rotundata) pertenecientes al banco de germoplasma de la Universidad de Sucre, durante un periodo de 8 meses. Esto mediante la modificación del medio de cultivo base MS; con los siguientes osmolitos: sacarosa, manitol y sorbitol. Se avaluaron 8 tratamientos (T) en los siguientes porcentajes T1 (control)(3:0:0), T2 (0:1,5:0), T3 (0:0:2), T4 (0:1,5:2), T5 (0:0:1) y T6 (0:0:3), T7 (0:1,5:1) y T8 (0:1,5:3). Cada 30 días se evaluó: supervivencia (%), hojas expandidas (%), longitud del tallo y raíz, número de nudos y raíces, oxidación (%), senescencia foliar (%) y callo (%). Los resultados mostraron que las especies D. alata y D. rotundata, se conservan de forma óptima, en la combinación T4 (0:1,5:2), donde se evidencia un alto porcentaje de supervivencia, un mínimo porcentaje de senescencia foliar y un desarrollo restringido en el resto de variables. Garantizando así la disponibilidad y el desarrollo normal de las accesiones en un periodo superior a 4 meses

Distributed Estimation of Distribution Algorithms for continuous optimization: how does the exchanged information influence their behavior?

One of the most promising areas in which probabilistic graphical models have shown an incipient activity is the field of heuristic optimization and, in particular, in Estimation of Distribution Algorithms. Due to their inherent parallelism, different research lines have been studied trying to improve Estimation of Distribution Algorithms from the point of view of execution time and/or accuracy. Among these proposals, we focus on the so-called distributed or island-based models. This approach defines several islands (algorithms instances) running independently and exchanging information with a given frequency. The information sent by the islands can be either a set of individuals or a probabilistic model. This paper presents a comparative study for a distributed univariate Estimation of Distribution Algorithm and a multivariate version, paying special attention to the comparison of two alternative methods for exchanging information, over a wide set of parameters and problems ? the standard benchmark developed for the IEEE Workshop on Evolutionary Algorithms and other Metaheuristics for Continuous Optimization Problems of the ISDA 2009 Conference. Several analyses from different points of view have been conducted to analyze both the influence of the parameters and the relationships between them including a characterization of the configurations according to their behavior on the proposed benchmark

CO2 emission factors and carbon losses for off-road mining trucks

There are myriad questions that remain to be answered in greenhouse gas (GHG) emissions trading. This article addresses carbon dioxide (CO2 ) emission factors and carbon losses from heavy equipment that is used to transport ores. Differences occurred between the Intergovernmental Panel for Climate Change (IPCC) emission factor and those that were obtained by considering incomplete combustion and on-site exhaust concentration measurements. Emissions from four off-road vehicles were analyzed. They operated at idle (loading, unloading, and queuing) and in motion (front and rear, loaded and unloaded). The results show that the average CO2 emission factors can be as low as 64.8% of the IPCC standard value for diesel fuel. On the other hand, carbon losses can be up to 33.5% and energy losses up to 25.5%. To the best of the authors’ knowledge, the method that was developed here is innovative, simple, useful, and easily applicable in determining CO2 emission factors and fuel losses for heavy machinery