Serkan Orhan, 030070165, 8th Week

1.TPOP (Time-Phased Order Point) [Group: Accounting]

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Many companies use economic order or shipping quantity/reorder ponit (Q,R) procedures based on demand forecasts for managing their field inventories. This means decisions for resupply are made independently at the field location, with no integrated forward planning; that is when the on-hand quantity at a location reaches the reorder point, the shipping quantity ordered with no thought given to any other items ordered, to the situation at the factory, or to warehouses-or to when the next order might be needed.

(Manufacturing Planning And Control For Supply Chain Management, Vollmann E., 2005, pg. 269-270)

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Time-phased order point (TPOP) is a method for determining inventory replenish-ment action based on the time-phased grid used in MRP. The purchase quantity is usually a fixed lotsize, but TPOP does allow for buying discretely, meaning only what the exact demand is.
The data that drives this type system includes a forecast of requirements, the lead-time of the item, and the order quantity. How does TPOP work? Forecasted demands, scheduled receipts, and available on-hand quantities are projected by week or periods over the planning horizon (usually 3 to 6 months). In each period the quantity available, plus the scheduled receipts. minus the forecast for the period equals the projected quantity available.
When the projected available inventory becomes negative, the need for a replenishment order is triggered. There are a number of advantages in the use of TPOP. It enables the use of predictable future requirements, rather than histori-cal data for order actions. It provides future visibility of when purchasing or production orders need to be issued. Forecasts can be adjusted for seasonality, trends, or discontinuous demand.
(Purchasing and Supply Management: Creating the Vision,Victor H. Pooler,David J. Pooler,1997,p. 176)


2)Extractives[Group: Material]
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A large variety of wood components, although usually representing a inor fraction, are soluble in neutral organic solvents or water. They are called extractives. The extractives compreise an extraordinarily large number of individual compounds of both lipophilic and hypdrophilic types. The extractives can be regarded as nonstructural wood consituents, almost exclusively compsed of extracellular and low-moleculaweight compounds. Similar type of constituents are present in so-called exudates, which are formed by the tree through secondary metabolism after mechanical damage or attack by insects or fungi. Although there are similarities in the occurence of wood extractives within families, there are distinct differences in the composition even between closely related wood species.
(Eero Sjöström, Wood Chemistry: Fundamentals and Applications ,pg:90)
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Extractives are generally removed from finely-ground wood samples by Soxhlet extraction with solvent for periods ranging from 4-18 hours. In the quantitative determination of extractives the air-dry ground wood sample (normally about 5 g oven-dry equivalent) is held in a paperboard thimble and continuously percolated and leached with solvent in a Soxhlet extraction unit equipped with an extraction flask and condenser; the number of extraction cycles generally being about four cycles per hour. The extract so obtained is evaporated and dried to constant weight and the extractive content determined. In the detailed study of individual extractives, for example those present in species about which little is known, extraction is undertaken on a larger scale. Techniques such as gas chromatography, mass spectrometry, and H¹and C¹³  nuclear magnetic resonance spectroscopy are often used in identification or structural elucidation of extractives by wood chemists.
(Primary Wood Processing: Principles And Practice,J. C. F. Walker,2006,p. 60)