How did the world change from an Asian centered economy to a global world economy? 1450 - 1750?

I am not sure what you mean by "Asian centered economy" and "global world economy", but by any definition I can think of, it didn't.

If you are just looking at GDP, whether you look at 1450 or at 1750, Asia dominated the world, with India and China being about equal and each of them about the same as western Europe.

http://en.wikipedia.org/wiki/List_of_regions_by_pa...

Asia still accounted for more than half the world GDP in 1820, though by 1870, the balance had tipped.

If you are asking about integration of economies. The European economy was not completely isolated from Asia in 1450, but the two were not closely tied. The same is true in 1750, though there was somewhat more trade (tea, porcelain, silk, etc.). But even then, the total international trade was smaller as a part of the economy than it had been during Roman times.

It was only later, when the Industrial Revolution really got going and Europe had enough advanced weaponry to make a difference that it used its military power to integrate Asian trade more closely that you see a major rise in trade.

For example, until 1842, European traders could only trade in a few designated Chinese ports:

http://en.wikipedia.org/wiki/Canton_Trade

(This was when Britain got Hong Kong)

Japan was opened up till 1853

http://en.wikipedia.org/wiki/Black_Ships

India didn't come under direct British control until the revolt against the East India Company in 1857

http://en.wikipedia.org/wiki/British_Raj

And even the East India Company wasn't a major trading force until the mid 1700s:

http://en.wikipedia.org/wiki/East_India_Company

The big growth in the Indian textile trade came with the mechanization of the early industrial revolution

http://en.wikipedia.org/wiki/Cotton#Industrial_rev...

And it was only with the development of ocean going steam boats that bulk trade became very profitable

http://en.wikipedia.org/wiki/Steamboat#Ocean-going...

Even the famed "tea clippers" had rather small freight capacity and were post 1750 (actually, early 19th century)

http://en.wikipedia.org/wiki/Clipper#China_clipper...