The the agriculture sector in developing countries has a large production share in the global fresh fruit market. Yet, in many cases, the land production yield indices at the orchard level are lower than the values related to more technologically developed countries. This situation leads to economic losses due to poor performance in productivity, efficiency and quality, which in turn is related to a technological and managerial gap. In this chapter, an operations management framework is proposed that tries to balance the market requirements (i.e. quality and quantity) with the capacity of the production system. This is performed through a multi-objective optimization approach that helps orchard managers synchronize the production yields with market demand and quality requirements. The model also allows the production managers to have a forecasting tool based on historical data. The model integrates the full supply chain through a set of sub-models for each stage of the production life cycle. The objective of the model is to minimize cost while maximizing sales. The optimization strategy involves a variant of the so-called NSGA II algorithm. The case study of an exporting lime packaging company is developed to illustrate the proposed framework and its possible impact on performance.
Airports represent the major bottleneck in the air traffic management system with increasing traffic density. Enhanced levels of automation and coordination of surface operations are imperative to reduce congestion and to improve efficiency. This paper addresses the problem of comparing different control strategies on the airport surface to investigate their impacts and benefits. We propose an optimization approach to solve in a unified manner the coordinated surface operations problem on network models of an actual hub airport. Controlled pushback time, taxi reroutes and controlled holding time (waiting time at runway threshold for departures and time spent in runway crossing queues for arrivals) are considered as decisions to optimize the ground movement problem. Three major aspects are discussed:1) benefits of incorporating taxi reroutes on the airport performance metrics; 2) priority of arrivals and departures in runway crossings; 3) tradeoffs between controlled pushback and controlled holding time for departures. A preliminary study case is conducted in a model based on operations of Paris Charles De-Gaulle airport under the most frequently used configuration. Airport is modeled using a node-link network structure. Alternate taxi routes are constructed based on surface surveillance records with respect to current procedural factors. A representative peak-hour traffic scenario is generated using historical data. The effectiveness of the proposed optimization methods is investigated.
MULTIFILE
This dissertation increases our insight into the role of the service employee’s intercultural competences in the service to culturally diverse customers. Investigating the effect of the intercultural competences of service employees is of major importance because, as a consequence of globalization, the number of intercultural service encounters has increased dramatically and still does. The delivery of service to a culturally diverse customer-base requires a combination of knowledge, skills and attitude; the intercultural competences (also known as Global Mindset). In this study the hotel sector has been investigated specifically. The hotel sector is an important economic player that continues to grow inspite of economic downturn. The special characteristics of hotel services make the sector also very suitable for the research of face-to-face encounters in an international context. In this dissertation, a holistic approach has been chosen, meaning that in the four empirical studies not only the perspective of the manager, but also that of the employee and the customer was investigated. All three of the above-mentioned are actors in intercultural service according to the argumentation of the ‘service-profit chain’ (Heskett, Jones, et al., 1994). Together, the manager, employee and the customer form the so-called ‘service triangle’ (Bitner, 1990).
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)
