Jatalla – New web search engine’s experience

Wikinews has reported a new web search engine called Jatalla, which uses only user generated submissions as results, is coming soon. It’s a different approach from the search engine leader Google, which rank relevance based in sites that link to a given web page, according to the PageRank alghoritm. Let’s wait for the beta version of the search engine, expected to go out in July. One interesting comment is in Jatalla’s FAQ, which says “If you believe (as do we!) that humans are still smarter than computers, you have come to the right place.

Google increasing its computing power

My friend Marcel Ferreira sent me this article which says Google is building two brand new data centers, as big as two football fields, on The Dalles, Ore. Google’s increasing power is reflected in the location of the data centers, near to a hidroeletric dam, in the Columbia river. Nice is “The cooling plants are essential because of the searing heat produced by so much computing power” :-).

Association or Aggregation?

I’ve been discussing with my co-workers when we have to use Aggregation or Association in UML models. Martin Fowler in UML Distilled, 3rd Edition says aggregation is the part-of relationship. It’s like saying that a car has an engine and 4 wheels as its parts. But aggregation was included in UML to differentiate from association, because in pre-UML days people didn’t knowhow to differentiate them. But aggregation, as Fowler says, is meaningless. Jim Rumbaugh says “Think of aggregation as a modeling placebo”. Association is a way to notate a property in our classes, but you don’t manage the life cycle of the associated property, as the aggregation relationship do. The solid line between the classes define the way one instance of the associating class can execute methods (operations realizations) of the associated object. So, why to use aggregation?