118 / 188
116
Marine plastic pollution has spread to become a problem of planetary scale after
only half a century of widespread use of plastic materials, calling for urgent management
strategies to address this problem. Clean-up activities on the shoreline could be
particularly effective in the Mediterranean Sea since shore deposition of floating debris
must be common in this semi-closed sea. However, as the production of plastic materials
will likely continue to increase in the coming decades, management strategies should
be addressed at the pollution sources in order to prevent the release of plastic discards
to the environment.
5.3 Inventories and storage
The material activities are aimed to perform so that right materials (raw-materials,
semi-products, supplies and final products) are at the right time at the right place at the
right quality at the preferred service level so that the long-range financial result of the
company is maximised. The general objects lead to the material management‘s objects
for inventories:
• To ensure efficient operation => minimise the total costs.
• To maximise the service level.
• To minimise the capital bound in the inventories.
With these objects a group of sub-objects can be formed: small unit costs, big
inventory turnover, the steady quality of purchased products, good relations to the
suppliers and the continuity of the deliveries.
These objects are partly in conflict with each other. The problem of the material
management is to find a suitable combination of objects in order to maximise the total
benefit. The essential questions of inventories are:
• Which inventory level should be chosen?
• How large should the supply batches be?
The decision is a compromise between two conflicting objects: minimisation of
the inventory capital and maximisation of the service level.
The storage must not be dealt as a function separate of its environment. When
changing the inventory system, the effects on the logistics chain both sides of the
inventory must be considered. We must remember that the sum of partial optimisations
is not the result of the total optimisation. The alteration of the inventory system must
be joined to alterations in distribution and production systems etc.
5.3.1 Motives of storage
Inventories can be divided according to the following different purposes:
1. Transportation and process inventories – these are materials bound into
transportation and process. These are substitutes for static inventories because:
• Storage is expensive.
• Requirements for delivery times get tighter.
• Market and supplying areas widen because of specialisation.
• Information traffic techniques are developing.