# Pallet Picking Strategy in Food Collecting Center
## 2 Literature Review
As a matter of fact, it is possible to ensure a low level of Carbon Footprint, with a minimal energy consumption, through adopting a specific material handling strategy through reducing the times of items retrieval and delivery in the warehouse [33]. According to [PERSON] and [PERSON] [34], the optimization of the routing policies is related to the identification of a batch order to be picked from the racks. This approach allows to minimize the total travel distance. For picker-to-part order picking system have been proposed different routing methods, including optimization algorithms. The performance of these heuristic approaches depends on the particular operating conditions of the system observed. It was estimated that the adoption of heuristic methods allows for an average reduction oscillating between 17% and 34% inside the path length of the forklift within the warehouse. In addition, the interaction between the routing strategy and the storage assignment adopted represents one of the most important aspects in the manual order picking approach [35]. In most studies the items to be stocked are considered like \"elementary units\" to operate in warehouses adopting multiple MHE, each of them characterized by a different loading capacity. In this case, the time spent in the picking activity depends on the number of units carried in each travel and on some technical specifications (travel speed, lift speed, capacity load, etc.) according to the MHE adopted. [PERSON] et al. in [35] developed a new model allowing the identification of the best MHE in order to minimize the Carbon Footprint due to material handling activities, ensuring at same time the picking time required by warehouse management system. Nonetheless, the studies concerning picking strategies leave several problems that still need to be solved. The review carried out by [PERSON] et al. in [30], is a useful guide to tackle them. The review states five decisional areas, bearing in mind that each one of those cannot be evaluated as a stand-alone component but has to be integrated and developed in synergy with the others. The rationale is further shown by observing how a single decisional area modification affect outcomes of others [30]. Therefore, the literature review shows that:  
1. Integrated models for the path routing identification and the storage assignment planning are not very widespread;
2. Most researches considering the environmental issue in warehouse activities are focused on specific'save-energy' aspects, and most of them are related to the building attributes;
3. There is a lack in available scientific works that considers environmental sustainability in an integrated inventory and warehouse planning model;
4. The order picking models ensure the reduction of the travel distance, retrieval time, or both, but in most cases the authors neglect the environmental performance and the management costs of the non-road vehicles adopted for material handling activities. This paper is intended to help fill these gaps, and in particular, to provide an approach for minimizing the environmental and economic impacts of the intra logistic activities by means of jointly evaluating all aspects concerning the material handling activities, including the typology of the forklift to be adopted (internal combustion or electric engine equipped), the layout of the warehouse (longitudinal layout, transversal layout, and fishbone layout), and the turnover index of the foodstuffs to be stocked. The Management of the Warehouse as a Factor of Competitiveness: The Case of Fresh Fruit and Vegetables  
In recent years, the need for a satisfying response from the production-logistic system to the complex demands of the market has been raised as a significant topic of discussion and reflection. This trend is probably due to a new physiological need of flexibility, understood as the ability of an economic organization to cope with a series of \"contingencies\", responding in a more economic and rapid manner to the environmental changes generated by the issue [19].