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An important contribution to the environmental impact of agro-food supply chains is related to the agricultural technology and practices used in the fields during raw material production. This problem can be framed from the point of view of the Focal Company (FC) as a raw material Green Supplier Selection Problem (GSSP). This paper describes an extension of the GSSP methodology that integrates life cycle assessment, environmental collaborations, and contract farming in order to gain social and environmental benefits. In this approach, risk and gains are shared by both parties, as well as information related to agricultural practices through which the FC can optimize global performance by deciding which suppliers to contract, capacity and which practices to use at each supplying field in order to optimize economic performance and environmental impact. The FC provides the knowledge and technology needed by the supplier to reach these objectives via a contract farming scheme. A case study is developed in order to illustrate and a step-by-step methodology is described. A multi-objective optimization strategy based on Genetic Algorithms linked to a MCDM approach to the solution selection step is proposed. Scenarios of optimization of the selection process are studied to demonstrate the potential improvement gains in performance.
For long flights, the cruise is the longest phase and where the largest amount of fuel is consumed. An in-cruise optimization method has been implemented to calculate the optimal trajectory that reduces the flight cost. A three-dimensional grid has been created, coupling lateral navigation and vertical navigation profiles. With a dynamic analysis of the wind, the aircraft can perform a horizontal deviation or change altitudes via step climbs to reduce fuel consumption. As the number of waypoints and possible step climbs is increased, the number of flight trajectories increases exponentially; thus, a genetic algorithm has been implemented to reduce the total number of calculated trajectories compared to an exhaustive search. The aircraft’s model has been obtained from a performance database, which is currently used in the commercial flight management system studied in this paper. A 5% average flight cost reduction has been obtained.
MULTIFILE
Airports and surrounding airspaces are limited in terms of capacity and represent the major bottleneck in the air traffic management system. This paper proposes a two level model to tackle the integrated optimization problem of arrival, departure, and surface operations. The macroscopic level considers the terminal airspace management for arrivals and departures and airport capacity management, while the microscopic level optimizes surface operations and departure runway scheduling. An adapted simulated annealing heuristic combined with a time decomposition approach is proposed to solve the corresponding problem. Computational experiments performed on real-world case studies of Paris Charles De-Gaulle airport, show the benefits of this integrated approach.
Treatment of crops with insecticides remains essential because globally more than 75 billion dollars is lost through crop destruction by invasive insects. However it is accompanied by severe disadvantages including i. increasing resistance of the target insects against insecticides and ii. the undesired lethality of beneficial insects such as bees and other pollinator species. The significant reduction of insect species during the last years, at least partly caused by the presently available insecticides has also effects on insect-eating species. Last but not least the presence of residual amount of insecticides in the environment (soil and plants), because of poor (bio)degradation, is another distinct disadvantage. Therefore, the overall aim of this proposal is to design and synthesize peptide based biopesticides. This should lead to Nature inspired green alternatives for insect control because "Peptides" are the small equivalents of "proteins", that are biomolecules, which are universally present in all organisms and subject to their natural biodegradation mechanisms, as well as also chemically degraded in the soil (water, heat, UV, oxygen). Design and synthesis of these environmentally benign compounds will eventually take place in a founded company called "INNOVAPEPLINE". Evaluation of candidate peptide based biopesticides can be carried out in collaboration with a recently founded company (spin-out of the University of Glasgow) called "SOLASTA BIO" (founders professors Shireen Davies, Julian Dow and Rob Liskamp) and/or with other (third) parties such as the University of Wageningen. Upon recent identification of promising candidate compounds ("leads"), chemical optimization studies of leads will take place, followed by evaluation in field trials. In this proposal design, synthesis and chemical optimization of the biological activity of new peptides and development of methods to monitor their biodegradation rate will take place. Thereby expanding the repertoire of peptide based biopesticides. (292 words)