030070104 Cebrail Yıldırım-7th week

Emulsifier (new&better) [Organic Mixture]

Emulsifier is an organic compound that encompasses in the same molecule two dissimilar structural groups e.g. water soluble and a water insoluble moiety. It is the ingredient which binds the water and oil in a cream or lotion together permanently. The composition, solubility properties, location and relative sizes of these dissimilar groups in relation to the overall molecular configuration determine the surface activity of a compound. Emulsifiers are classified on the basis of their hydrophilic or solubilizing groups in to four categories anionic, non ionic, cationics and amphoterics. Emulsifier is utilized in various industries; agriculture, building and construction, elastomers & plastics, food & beverages, industrial cleaning, leather, metals, paper, textiles paints & protective coatings etc.

(NPCS Board of Consultants & Engineers,The Complete Book on Emulsifiers with Uses, Formulate and Processes , NIIR Project Consultancy Service)

Emulsifier (previous)
Two types of emulsifiers, hydrophilic and lipophilic are available. Hydrophilic emulsifiers are composed of materials similar to common detergents, which react with the oil based penetrant in a way that removes the penetrant from the surface. Diffusion plays a minor role in the action of the hydrophilic emulsifiers. Lipophilic emulsifiers, on the other hand, are oil soluble and they diffuse into penetrant, breaking down the structure so that the penetrant may be rinsed away with water. There are a number of methods used in the cleaning process such as wiping with a cloth, dipping in a tank, rinsing with a hıse, or some combination of these. (Practical non-destructive testing, 2nd Edition, Raj, p.11)

New definition gives more obvious description.

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Process Manufacture(first&best) [Process]:

Production process followed a plant for converting semi-finished products or raw materials into finished products. The art of converting raw materials into finished goods with application of different types of tools, equipments, machine tools, manufacturing set ups and manufacturing processes, is known as production. Manufacturing process is that part of the production process which is directly concerned with the change of form or dimensions of the part being produced. It does not include the transportation, handling or storage of parts, as they are not directly concerned with the changes into the form or dimensions of the part produced.

(Rajender Singh, Introduction to basic manufacturing processes and workshop technology, pg 3)

There is no previous definition.
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Fracture mechancics (new&better) [Field of Mechanics]

Fracture mechancics, or the mechanics of fracture, is a branch of engineering science that addresses the problem of the integrity and indurability of materials or structural members containing cracks or cracklike defects. The presence of cracks may be real, having been introduced through the manufacturing processes or during service. On the other hand, their presence may have to be assumed because limitations in the sensivity of nondestructive inspection procedures preclude full assurance of their absence. The perspective view of fracture mechanics can be gained from the following questions:

1.                               How much load will it carry, with and without cracks? (a question of structural safety and integrity)

2.                               How long will it last, with and without cracks? Alternatively, how much longer will it last? (a concern of durability)

3.                               Are you sure? (the important issue of reliability)

4.                              How sure? (confidence level)

(Robert Peh-ying Wei, 2010, Fracture Mechanics: Integration of Mechanics, Materials Science, and Chemistry)

Fracture Mechanics:  (previous)

Fracture mechanics is the study of mechanical behavior of cracked materials subjected to an applied load. In fact, Irwin developed the field of fracture mechanics using the early work of Inglis, Griggith and Wester gaard. Essentally, fracture mechanincs deals with the irreversible process of rupture due to nucleation and growth of cracks. The information of cracks may be a complex fracture process, which strongly depends on the microstructure of a partcular crystalline or amorphous solid, applied loading and enviorement. The microstructure plays a very important role in a fracture process due to dislocation motion, precipitates, inclusions,grain size and type of phases making up the microstructure. All these microstructural feature are imperfections and can act as fracture nuclei under unfavorable conditions.
(Nestor Perez, Fraction Mechanics, pg: 25)

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Badwith Concept  (new)

The Bandwith concept  can be defined as the time difference, in seconds, between the trajectories of the first and last vehicle in a platoon of vehicles capable of moving through a series of  intersections without having to stop at any of these intersections. Bandwith efficiency  gives a indication of the efficiency of the coordination scheme.
 (Transportation Infrastructure Engineering, Lester A. Hoel etc. )


Bandwidth Concept (old)
Depending on the area of networking, bandwidth can take on a couple of different meanings. The concept of bandwidth originated in wireless applications, such television broadcast, microwave, and radio. It was often used to convey a spectrum of frequencies, often expressed in units of hertz, available for use by a transmitter or receiver. This spectrum is often referred to as a channel. This concept was later extended to the voice and data networking worlds as well. In these worlds, bandwidth is often used to convey data speed. This is actually not exactly accurate. Because it indicates how much data, in bits or bytes, flows between two points in a given time, it is actually a transfer rate. (Mission-critical network planning, Liotine, p.53)

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Order Point Methods  (old better)
Once the components of statistical replenishment have been determined for each product, inventory planners have the option of selecting from four basic order point techniques. These methods can be divided into two types based on the point when items are reviewed for possible replenishment. Two of the techniques (order point and min/max) are dependent on a continuous rewiev cycle, whereas the remaining two (period order quantity and line point) are considered as periodic review ordering systems. (Distribution: planning and control, 2nd Edition, Ross, p.322)

Order Point Methods (new)

A set inventory level where, if the stock on hand plus on order falls to or below order point, action is taken to replenish the stock. The order point is normally calculated as, forecasted usage during the replenishment lead time plus safety stock. The order methods is the method whereby  replenisment orders are triggered (launched) at a calculated inventory level (order point level).
(Production and inventory management, Hoffmann etc., p.834)