Monday, April 16, 2012

Ahmet Can OLDAÇ- 030060098- week8

Ferrimagnetic Ceramic Materials:(old)
Ferrimagnetic materials represent a class of ceramic materials that are widely used in high-frequency applications. They are divided in garnets and ferrites, the latter being much more important in shielding applications because of their larger values of the relaticve magnetic permeability and of their larger losses. Ferrites have a crystal structures and are sintered by means of various metal oxides, obtaining high values of the magnetic permability. Theese kidn of materials are usually further classified bas either soft or hard magnetic materials, but when their magnetizing source is removed, these materials lose their magnet-lke behaviour.
(Donald R. Askeland, Pradeep Prabhakar Phule, The Science and Engeineering of Materials, pg:726)



Ferrimagnetic Ceramic Materials(new): [material]


Ferrimagnetism occurs when the magnetization of magnetic domains with unequal magnitude are antiparallel to each other, resulting in a net spontaneous magnetization. Ferrites, which are also ferrimagnetic, are among the most important magnetic ceramic materials.


Ferrites are oxide ceramics where Fe2O3 is the major component. The term "ferrite" is synonymously used with magnetic ceramics. Common applications of ferrites include waveguides, rectifiers, resonance isolators, junction circulators, and phase shifters. These parts are used in devices taht employ microwaves for communication devices (television, computers, telefax machines, and press copy), radar and heating. Typically, ferrites have a crystal structure, which has more than one type of site for cations. Usually, the magnetic moments of metal ions on sites(domains) of one type are parallel to each other and antiparallel to the moments of another type. Thus ferrites are ferrimagnetic. The three classes of ferrites are spinels, garnets and hexagonal ferrites.


(Engineering Ceramics Author: Murat Bengisu p.343)
-new definition is more clear and better
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4.Part Period Balancing(old)
The part period balancing (PPB) procedure uses all the information provided by the requirements schedule. In determining an order’s lot size, this procedure tries to equate the total costs of placing orders and carrying inventory.
(Manufacturing Planning And Control For Supply Chain Management, Vollmann E., 2005, pg. 481)

Part Period Balancing(new) [accounting]


In the conventional EOQ application, the optimal EOQ results when the set-up cost is equal to the carrying cost. The PPB method attempts to exploit this property of equalizing the set-up cost and carrying the cost to establish what is known as Economic Part Period (EPP).

(Production and Operations Management Author: R. Panneerselvam p.273)
-new definition is more clear and understandable.
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Transit Stock(old):
The delivery lead-time from the plant to the DC is about one day. As the stock for this transport is not considered on the are, the minimum stock in the DC has to be increased by this amont. Whil the transportation link, there exists also inventory that is currently transported in-between. This stock component only depends on the transportation time and the demand because on average the inventory held on the truck equals the demand which occurs during the transportation time.
(Hartmut Stadtler, Suplain Change Manangement and advanced planing ,pg:459)




Transit Stock(new) [supply chain]


All the demand(D) in the system will have to be replenished at some time. The total cost model assumes that there will be no net change in the inventories over time, so that the input equals the output. Inventory takes time to be transported to its storage palce. Thus, the averange inventory in transit is based on the transit time(which is a function of the replenishment quantity when the quantity chioce leads to use of a slower or faster transportation option), and the expected demand volume during the period for which we are computing the total costs. This stock of goods on the move is called Transit stock.


(The Logistics Handbook Author: James F. Robeson p.367)
-new definition is more clear and better


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