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Mapping crop and livestock value chain actors in Mbire and Murehwa districts in Zimbabwe

Hambulo Ngoma Moti Jaleta Frédéric Baudron (2023, [Documento de trabajo])

We conducted a preliminary value chain actors mapping for major crops grown and livestock kept by smallholder farmers in Mbire and Murehwa districts of Zimbabwe. Accordingly, in this report we mapped value chain actors for 11 crops and livestock commodities: namely, sorghum, cotton, sesame, maize, groundnut, sweet-potato, vegetables (tomato and onion), cattle, goats, poultry, and honey/beekeeping. Except sesame from Mbire, most of the crop and livestock commodities are channeled to the main markets in Harare and Marondera for Murehwa. Sesame is smuggled to Mozambique and the market is mainly dependent on middlemen. The Grain Market Board (GMB) is the major actor in sorghum and maize marketing in both districts. Groundnut is sold to both rural and urban consumers after processing it to peanut butter locally within the production zones. Goats and cattle are mostly supplied to the Harare market by middlemen collecting these livestock from village markets and moving door-to-door to buy enough quantity to transport to Harare. Honey production and marketing is still at its initial stage through the support of HELP from Germany and the Zimbabwe Apiculture Trust projects. Long dry season is a challenge in honey production. The Pfumvudza program supported by the Presidential free input scheme helped in introducing and scaling conservation agriculture practices in Zimbabwe. Though there is strong integration of crop-livestock systems at both districts, the level of manure use is gradually decreasing because farmers receive chemical fertilizer support from the Pfumvudza program and applying manure to crop fields is labor-intensive. The input supply system is more competitive in Murehwa district where there are quite several input suppliers in town. The possible interventions that favor agroecological transitions are: (1) honey processing plants and supply of beehives to potential areas, (2) encouraging manure use in crop production, possibly linking it to the basins preparation requirement to be eligible for the presidential input subsidy scheme, (3) support the organic vegetable production initiatives and explore market segments in Harare paying premium prices for certified organic products, (4) Expedite payment systems in sorghum and maize marketing with GMB, and (5) sesame production with agroecologically friendly agronomy and improve markets.

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA VALUE CHAINS CROPS LIVESTOCK SMALLHOLDERS SUPPLY CHAINS

Detección de eventos violentos en publicaciones de redes sociales

Detection of violent events in social media publications

Esteban Ponce León (2023, [Tesis de maestría])

En los últimos años, ha habido un interés creciente en el monitoreo de redes sociales para recopilar información y, en algunos casos, para examinar la ocurrencia de delitos. Sin embargo, gran parte de las investigaciones hasta ahora solo se han centrado en ciudades de EE. UU. o extranjeras, y por ende, en publicaciones y conjuntos de datos en inglés El objetivo principal de esta tesis es diseñar un método que permita la identificación de publicaciones de eventos violentos en español y en Twitter, utilizando información multimodal y técnicas de aumento de datos que mejoren el rendimiento de los modelos. Para esto, el trabajo de investigación se dividió en dos fases experimentales. La primera orientada a identificar publicaciones a partir de solo texto, explorando diferentes técnicas de aumento de datos para texto y modelos de aprendizaje máquina y profundo. En la segunda fase, se extendió el método propuesto para abordar la identificación en un contexto multimodal, es decir, considerando tanto los textos de los tweets como las imágenes compartidas que los acompañan. En este caso el método propuesto consideró utilizar descripciones textuales de las imágenes y abordar la problemática desde el dominio textual, además se hicieron 2 tipos de aumento de datos para cada tipo de información. La evaluación de los métodos se hizo utilizando las colecciones de la tarea de evaluación DA-VINCIS 2022 y 2023. Los resultados demostraron una mejora en el rendimiento de los modelos al considerar el uso de información multimodal y el uso de aumento de datos.

In recent years, there has been a growing interest in monitoring social networks to gather information and, in some cases, to examine the occurrence of crime. However, much of the research so far has only focused on US or foreign cities, and thus on English-language publications and data sets. The main objective of this thesis is to design a method that allows the identification of publications of violent events in Spanish and on Twitter, using multimodal information and data augmentation techniques that improve the performance of the models. For this, the research work was divided into two experimental phases. The first aimed at identifying publications from only text, exploring different data augmentation techniques for text and machine and deep learning models. In the second phase, the proposed method was extended to address identification in a multimodal context, that is, considering both the texts of the tweets and the shared images that accompany them. In this case, the proposed method considered using textual descriptions of the images and addressing the problem from the textual domain, in addition, 2 types of data augmentation were made for each type of information. The evaluation of the methods was done using the collections of the DA-VINCIS 2022 and 2023 evaluation task. The results demonstrated an improvement in the performance of the models when considering the use of multimodal information and the use of data augmentation.

Detección de Violencia, Redes Sociales, Aumento de Datos, Procesamiento del Lenguaje Natural, BERT, BETO, Descripción de Imágenes Violence Detection, Social Networks, Data Augmentation, Natural Language Processing, BERT, BETO, Image Captioning INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE LOS ORDENADORES MODELOS CAUSALES MODELOS CAUSALES

Modelación hidráulica de un reactor de electrocoagulación tubular de sección anular

JAVIER DE JESUS CANTO RIOS Alejandra Martín-Domínguez Sara Pérez-Castrejón VICTOR HUGO ALCOCER YAMANAKA Velitchko Tzatchkov (2017, [Artículo])

El presente trabajo se enfoca en el estudio de las pérdidas de carga totales en un reactor de electrocoagulación con flujo a presión y sección transversal anular simple y múltiple, donde esta última característica depende del arreglo de los electrodos. Se presenta el análisis de las pérdidas de carga por cortante y accesorios, las cuales se modelaron utilizando diferentes expresiones empíricas y se compararon con las mediciones realizadas a escala semipiloto. Como resultado del análisis se observó que la ecuación de Bahramir, Yovanovich y Culham (2006) asemeja las pérdidas reales en secciones anulares múltiples, mientras que la expresión propuesta por Davis describe mejor la sección anular simple. Estos resultados permitirán tener herramientas para diseñar reactores de electrocoagulación a escala real.

Electrocoagulación Modelación Pérdidas de carga hidráulica Secciones anulares INGENIERÍA Y TECNOLOGÍA

Alternative cropping and feeding options to enhance sustainability of mixed crop-livestock farms in Bangladesh

Timothy Joseph Krupnik Jeroen Groot (2024, [Artículo])

We investigated alternative cropping and feeding options for large (>10 cows), medium (5–10 cows) and small (≤4 cows) mixed crop – livestock farm types, to enhance economic and environmental performance in Jhenaidha and Meherpur districts – locations with increasing dairy production – in south western Bangladesh. Following focus group discussions with farmers on constraints and opportunities, we collected baseline data from one representative farm from each farm size class per district (six in total) to parameterize the whole-farm model FarmDESIGN. The six modelled farms were subjected to Pareto-based multi-objective (differential evolution algorithm) optimization to generate alternative dairy farm and fodder configurations. The objectives were to maximize farm profit, soil organic matter balance, and feed self-reliance, in addition to minimizing feed costs and soil nitrogen losses as indicators of sustainability. The cropped areas of the six baseline farms ranged from 0.6 to 4.0 ha and milk production per cow was between 1,640 and 3,560 kg year−1. Feed self-reliance was low (17%–57%) and soil N losses were high (74–342 kg ha−1 year−1). Subsequent trade-off analysis showed that increasing profit and soil organic matter balance was associated with higher risks of N losses. However, we found opportunities to improve economic and environmental performance simultaneously. Feed self-reliance could be increased by intensifying cropping and substituting fallow periods with appropriate fodder crops. For the farm type with the largest opportunity space and room to manoeuvre, we identified four strategies. Three strategies could be economically and environmentally benign, showing different opportunities for farm development with locally available resources.

Ruminant Feed Pareto-Based Optimization Farm Bioeconomic Model CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA RUMINANT FEEDING BIOECONOMIC MODELS MIXED CROPPING FARMS LIVESTOCK