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Wet Spinning  and Dry Spinning(new):manufacturing method

Quenching of filaments, so that they do not stick together, is easier when the dope is spun into liquid bath, so many more filaments can be spun from a single spinneret in wet spinning.

The spinnabilitiy of polymer solution is limited, as in melt spinning, by surface tension instability and cohesive fracture. In dry spinning the first mechanism is operative and results in dripping in place of continuous spinning.the second mechanism, namely cohesive fracture, appears to be more important in wet spinning.

In wet spinning such high crystalization temperatures are usually unattainable. In wet spinning,the relatively low temperature of the coagualation bath and the high hydraulic drag cause a much higher degree of orientation compared with dry spinning.

Taking advantage of flexibility of the wet spinning process,a wide variety of cross  sectional shapes can be produced.

(V. B. Gupta, V. K. Kothari, Manufactured fibre technology, p.135)

There is not old definition

Database management systems(technology)

Old:

Database management systems based on the relational model could provide the environment in which unstructured information needs would be met by employing ad hoc queries. End users would be given the ability to access data when needed. Unfortunately, the early relational model implementations did not yet deliver acceptable throughput when compared to the well- established hierarchical or network database models.

The last two decades gave birth to a series of crucial social and technological changes that affected database development and design. Among those changes were:

* Business operations became decentralized

* Competition increased at the global level.

* Customer demands and market needs favored a decentralized managament style.
(Database Systems: Design, Implemantation and Management, Peter Rob, page 478)

New:better

Database management system (DBMS) and Oracle no formal introduction. All the computer based applications largely use database in some form or the other.DBMS is essentially a part of the curriculum for undergraduate and post graduate courses in computr science,computer applications, computer science and engineering and information technology.It has also been extensively used by several other branches of engineering dealing data.

In short it can be safely concluded that DBMS is indispensable and act as a life source for the students of engineering, management and science.

(Gupta D., Database Management System,p.13)

Green Design: (product design)

Old: (beter)

A major emphasis is on design for environment (DFE) or green design. This approach anticipates the possible adverse environmental impact of materials, products, and processes, so that it can be taken into account at the earliest stages of design and production. The main objectives are to prevent pollution at the source an to strongly promote recyclying and reuse instead of disposal.
(Kalpakjian S., Schmid S.R., Manufacturing Engineering and Technology,5th Edition, page.33)

New:

Gren design shoul form the foundation for exploration and discovery of new and innovative ways to minimize ecological footprints. But it must be even more than avoiding the negative.now and from now on designers must strive for an end product that mutually benefits the client the public and the environment.

(Vallero D. A., Brasier C. ,Sustainable design, p.1)

Pre-production Prototypes(production process)

Old:

Preproduction prototypes are the first products produced by the entire production process.At this point the production process is not yet operating at full capacity but is making limited quantities of the product.These prototypes are used to verify production process capability, are subjected to further testing, and are often supplied to preferred customers.Preproduction prototypes are sometimes called pilot-production prototypes.

(Kalpakjian, Smith; Manufacturing Engineering and Technology,p. 261)

New(beter)

A pre-production prototype is a sample created by manufacturer prior to mass production. Accuracy depends on the type of product you wish to prototype. For example, if your product involves fabrics such as hats, clothing, pillows or backpacks and if everything goes well you will get a pre- production prototype with high accuracy to the actual mass product.

(Chuah K., The 5-second Inventor, p,75)