@masterThesis{10818/51587,
year = {2022},
month = {5},
url = {http://hdl.handle.net/10818/51587},
abstract = {Farmers’ markets are a potential strategy to mitigate food insecurity since they can serve 
fresh food (especially fruits and vegetables) to cities without the complex structure of 
traditional food supply chains. These markets are part of short supply chains that connect 
producers directly with clients without intermediaries. However, the planning of this supply 
strategy has been empirical, sometimes locating markets where they are not necessary. 
Only a few studies in the literature have analyzed the farmers’ market network design, but 
they have not considered the market behavior related to the consumers’ preferences. This is 
the reason for this study. Considering the market environment, we developed a competitive 
facility location problem to design a network of farmers’ markets. To this goal, we 
employed a mixed-integer nonlinear programming model. As factors that affect the 
selection of a seller, we used price, distance, and waiting time to measure the quality of 
service. Due to its inherent difficulty, we developed a beam search algorithm integrating a 
greedy randomized component as an approximate solution method compared to the exact 
solutions of this model. The results present a high-quality algorithm performance with 
computational times lower and gaps of no more than 2%. This model was applied in a case 
study in Bogotá, where we found that the most critical factors to increase the demand 
captured by farmers’ markets are low prices and the maximum number of farmers’ markets 
to open per week. However, the market share is not larger than 0.5%; hence it is necessary 
to consider other policies for its working.},
abstract = {Los mercados campesinos son una estrategia potencial para mitigar la inseguridad 
alimentaria, ya que pueden proveer alimentos frescos (especialmente frutas y verduras) a 
las ciudades sin la compleja estructura de las cadenas tradicionales de suministro de 
alimentos. Estos mercados consisten en cadenas de suministro cortas que conectan a los 
productores directamente con los clientes sin intermediarios. Sin embargo, la planificación 
de esta estrategia de abastecimiento ha sido empírica, ubicando en ocasiones los mercados 
donde no son necesarios. Sólo cuatro estudios en la literatura han analizado el diseño de la 
red de mercados campesinos, pero no han considerado el comportamiento del mercado 
relacionado con las preferencias de los consumidores. Este es el motivo de este estudio. 
Teniendo en cuenta el entorno del mercado, desarrollamos un competitive facility location
para diseñar una red de mercados campesinos. Para ello, empleamos un modelo de 
programación no lineal de enteros mixtos. Como factores que afectan a la selección de un 
vendedor, utilizamos el precio, la distancia y el tiempo de espera para medir la calidad del 
servicio. Desarrollamos un algoritmo beam search que integra un componente greedy 
aleatorio como método de solución aproximada para encontrar buenos resultados en 
comparación con las soluciones exactas de este modelo. Los resultados presentan que el 
rendimiento del algoritmo es de alta calidad, con tiempos computacionales muy bajos y 
desfases no superiores al 2%. Este modelo fue aplicado en un estudio de caso en Bogotá, 
donde encontramos que los factores más críticos para aumentar la demanda captada por los 
mercados campesinos son los precios bajos y el número máximo de mercados a abrir por 
semana. Sin embargo, la demanda captada no supera el 0,5%, por lo que es necesario 
considerar otras políticas para el funcionamiento de los mercados campesinos.},
organization = {Farmers’ markets are a potential strategy to mitigate food insecurity since they can serve fresh food (especially fruits and vegetables) to cities without the complex structure of traditional food supply chains. These markets are part of short supply chains that connect producers directly with clients without intermediaries. However, the planning of this supply strategy has been empirical, sometimes locating markets where they are not necessary. Only a few studies in the literature have analyzed the farmers’ market network design, but they have not considered the market behavior related to the consumers’ preferences. This is the reason for this study. Considering the market environment, we developed a competitive facility location problem to design a network of farmers’ markets. To this goal, we employed a mixed-integer nonlinear programming model. As factors that affect the selection of a seller, we used price, distance, and waiting time to measure the quality of service. Due to its inherent difficulty, we developed a beam search algorithm integrating a greedy randomized component as an approximate solution method compared to the exact solutions of this model. The results present a high-quality algorithm performance with computational times lower and gaps of no more than 2%. This model was applied in a case study in Bogotá, where we found that the most critical factors to increase the demand captured by farmers’ markets are low prices and the maximum number of farmers’ markets to open per week. However, the market share is not larger than 0.5%; hence it is necessary to consider other policies for its working.},
publisher = {Universidad de La Sabana},
title = {Improving food security with farmers' markets in Bogotá, Colombia : A logistics perspective},
author = {Granados Rivera, Daniela},
}