Abstract:

The swap body vehicle routing problem (SB-VRP) is a generalization of the classical vehicle routing problem where a particular structure as well as several operational aspects for the trucks composing the fleet are considered. This research has been motivated by the VeRoLog Solver Challenge 2014, organized together by VeRoLog and PTV group, aiming to motivate the study of real-world logistic problems. A truck can carry either only one swap body or, in addition, an extra trailer with an extra swap body. For the latter, special depots, called swap locations, can be used to drop and pickup the swap bodies. These operations may affect the feasibility and the cost of a route, and therefore the overall operational cost. In this paper, we propose a cluster-first route-second heuristic for the SB-VRP. Computational experiments are conducted over the benchmark instances proposed for the competition, simulating a practical environment by considering limited resources and execution time. The results obtained are of very good quality, where our approach ended as runner-up in the final set of instances and performs similarly to the other algorithms in the remaining cases, showing its potential to be applied in practice.

Author affiliation: Miranda Bront, Juan Jose. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Computación; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Curcio, Brian Luis. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Computación; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Méndez-Díaz, Isabel. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Computación; Argentina

Author affiliation: Montero, Agustin Ismael. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Computación; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Pousa, Federico Javier. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Computación; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Zabala, Paula Lorena. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Computación; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Abstract:

This paper studies the changes of groundwater, climate and land use in the Pampas of Argentina. These changes offer opportunities and threats. Lowering groundwater without irrigation causes drought and successive crop and yield damage. Rising groundwater may alleviate drought as capillary rise supports root water uptake and crop growth, thus narrowing the difference between potential and actual yields. However, rising groundwater may also limit soil water storage, cause flooding in metropolitan areas and have a negative impact on crop yields. Changing land use from continuous soy bean into crop rotations or natural vegetation may decrease groundwater recharge and thus decrease groundwater levels. In case of crop rotation however, leaching of nutrients like nitrate may increase. We quantified these impacts using integrated dynamic crop growth and soil hydrology modelling. The models were tested at field scale using a local dataset from Argentina. We applied distributed modelling at regional scale to evaluate the impacts on groundwater recharge and crop yields using long term weather data. The experiments showed that threats arise from continuous monotone land use. Opportunities are created when a proper balance is found between supply and demand of soil water using a larger differentiation of land use. Increasing the areas of land use types with higher evapotranspiration, like permanent grassland and trees, will contribute to a more stable hydrologic system with more water storage capacities in the soil system and lower groundwater levels. Modelling tools clearly support the evaluation of the impact of land use and climate change on groundwater levels and crop yields.

Instituto de Clima y Agua

Author affiliation: Kroes, Joop. Wageningen University and Research. Chair Soil Physics and Land Management; Holanda

Author affiliation: van Dam, Jos. Wageningen University and Research. Chair Soil Physics and Land Management; Holanda

Author affiliation: Supit, Iwan. Wageningen University and Research. Chair Water Systems and Global Change; Holanda

Author affiliation: De Abelleyra, Diego. INTA. Instituto de Clima y Agua; Argentina

Author affiliation: Veron, Santiago Ramón. INTA. Instituto de Clima y Agua; Argentina

Author affiliation: de Wit, Allard. Wageningen University and Research. Wageningen Environmental Research. Unit Earth Observation and Environmental Informatics; Holanda

Author affiliation: Boogaard, Hendrik. Wageningen University and Research. Wageningen Environmental Research. Unit Earth Observation and Environmental Informatics; Holanda

Author affiliation: Angelini, Marcos Esteban. INTA. Instituto de Suelos; Argentina. Wageningen University. Soil Geography and Landscape group; Holanda. International Soil Reference and Information Centre. World Soil Information; Holanda.

Author affiliation: Damiano, Francisco. INTA. Instuto de Clima y Agua; Argentina

Author affiliation: Groenendijk, Piet. Wageningen University and Research. Wageningen Environmental Research, Unit Sustainable Soil Use; Holanda

Author affiliation: Wesseling, Jan. Wageningen University and Research. Chair Soil Physics and Land Management; Holanda

Author affiliation: Veldhuizen, Ab. Wageningen University and Research. Wageningen Environmental Research. Unit Soil, Water and Land Dynamics; Holanda

Abstract:

El estallido de la crisis económica mundial en 2008 fue vista por China como una ventana de oportunidad para la creación de poder estructural en la dimensión de las finanzas y crédito a través de la internacionalización del yuan. En este sentido, uno de los mecanismos por el cual la República Popular China procuró –y aun procurapromover dicho proceso fue a través de la firma de acuerdos swaps de monedas. En virtud de lo expuesto, la presente tesis describe la estrategia china de construcción de poder a través de los acuerdos swap de monedas. A su vez, analiza los casos de Argentina y Brasil, los cuales se integraron a la estrategia china para evitar los efectos adversos de la crisis mundial. En este marco, ambos países latinoamericanos fueron receptores de la estrategia china de construcción de poder estructural y se sumaron al poder relacional chino en tanto que actuaron conforme a las reglas definidas por la potencia asiática e intentaron defender sus intereses en un juego ya predeterminado por dicho país. En el caso de Argentina, el acuerdo swap fue utilizado con el propósito de hacer frente a las urgencias financieras domésticas, en detrimento del uso de los yuanes para promover el intercambio comercial bilateral. En el caso de Brasil, y en tanto que no atravesaba ningún tipo de emergencia financiera interna, firmó el acuerdo swap a modo de prevenir una elevada demanda de liquidez hacia el Banco Central de Brasil y como forma de complementar las políticas que este país llevaba a cabo con China en el marco de los BRICS. No obstante, el acuerdo firmado con Brasil no se activó ni se renovó al finalizar su término. Esta situación da cuenta de cómo una estrategia universal y única como la que impulsa China a través de los acuerdos swaps, tuvo similares respuestas en Argentina y Brasil en cuanto a su aceptación y un uso disímil según las necesidades de ambas partes a través de idénticas formas

The outbreak of the global economic crisis in 2008 was seen by China as a window of opportunity for the creation of structural power in the finance and credit dimensions through the internationalization of the yuan. In this sense, one of the mechanisms by which the People's Republic of China has sought -and still seeks- to promote this process has been the signing of currency swap agreements. In view of the above considerations, this thesis describes the Chinese strategy of power building through currency swap agreements. Moreover, it analyzes the cases of Argentina and Brazil, which were integrated to the Chinese strategy to avoid the adverse effects of the global crisis. In this context, both Latin American countries were recipients of the Chinese strategy of construction of structural power and joined the Chinese relational power as they acted according to the rules defined by the People's Republic of China and tried to defend their interests in an already predetermined game. In the case of Argentina, the swap agreement was used for the purpose of dealing with domestic financial emergencies, to the detriment of the use of the Yuan to promote bilateral trade. In the case of Brazil, who was not experiencing any kind of internal financial emergency, the swap agreement was signed in order to prevent a high demand on the liquidity of the Central Bank of Brazil and as a way to complement the policies that this country led with China in the framework of the BRICS. However, the agreement signed with Brazil was neither activated nor renewed. This situation explains how a universal and unique strategy, such as the one promoted by China through swap agreements, can take different forms depending on the needs of each partner country

Author affiliation: Chiacchiera, Magalí Andrea. Universidad Nacional de Rosario. Facultad de Ciencia Política y Relaciones Internacionales; Argentina