February 18th, 2009

"Not an angel"

Google's best-kept secret - PidgeonRank!

PigeonRank's success relies primarily on the superior trainability of the domestic pigeon (Columba livia) and its unique capacity to recognize objects regardless of spatial orientation. The common gray pigeon can easily distinguish among items displaying only the minutest differences, an ability that enables it to select relevant web sites from among thousands of similar pages.

By collecting flocks of pigeons in dense clusters, Google is able to process search queries at speeds superior to traditional search engines, which typically rely on birds of prey, brooding hens or slow-moving waterfowl to do their relevance rankings.

diagramWhen a search query is submitted to Google, it is routed to a data coop where monitors flash result pages at blazing speeds. When a relevant result is observed by one of the pigeons in the cluster, it strikes a rubber-coated steel bar with its beak, which assigns the page a PigeonRank value of one. For each peck, the PigeonRank increases. Those pages receiving the most pecks, are returned at the top of the user's results page with the other results displayed in pecking order.


Today's word is "ablation cascade" (aka Kessler Syndrome)

Since satellites may disintegrate when struck by fast-moving space junk, the crash focuses concern that a future dramatic satellite collision may one day start an ablation cascade of increasingly more collisions. The result could then render future human space flights increasingly risky and expensive satellite lifetimes increasingly short.





Dirk had an accident. Below is the X-ray showing his totally crushed finger tip. It took 1 1/2 hours of surgery to remove the shattered bones and repair the damage. Medically speaking, he crushed his right index finger distal phalange. The magnets had a 50 cm (20 inch) separation when they decided to fly together.

He is lucky that he only lost a finger tip as opposed to his whole hand. The block Neo below is about 4" by 2" by 2" N45 with a pull force of around 700 lbs (320 kg). The disk is about 3" dia. by 2 1/2" thick N45 with a pull force of about 400 lbs (180 kg). That is his fingernail and some of his finger tip caught between the magnets.


Warning: graphic images.