2008-01-26

Carbon dioxide emissions

Funny - my car (Toyota Prius) emits less carbon dioxide than if it's passengers would have been walking or running the same distance. This is the only such car.

A typical 70kg human burns about 75Kcal fat per km (running. Walking is even less efficient). That is about 1.05kg fat per 100km. Toyota Prius at slow cruise (80kph) burns about 3.3liters per 100km and can carry 5 passengers. Human fat has about the same energy density than octane (roughly 25% less).

It seems like lack of wheels is what makes our bodies so inefficient.


Speaking of which - many people attribute Prius efficiency to the hybridity - ability to regenerate energy back from breaking. They don't know that this is only one third of it's story. The #1 invention in the Prius is a unique continuously-variable transmission, of a type only possible in a hybrid car. The so-called ECVT, only possible in a hybrid car, is a complete wonder. It's a very lightweight transmission, which is truly continuous but does not have any ribbons or cones - all the way rigid toothwheels. How is that at all possible - is an amazing story. The third part is of course the Atkinson-cycle engine, which beats the inherent thermodynamic inefficiency of the 4-stroke ICE.

2008-01-23

Airline seats

People are always being asked whether I prefer the window set or the aisle one. Dima95, however, provided an eye-opening idea: the best seat in the airplane is the middle one.

This way you have two neighbors, and you can choose which one is less annoying to talk to (or possibly, more pleasant to sleep on). Also you can seal the other two off from communicating - this ensures that they don't get any pairs/couples in your line who probably reserved two consequent seats from ahead of time so that they can sit together - further increasing chances of interesting interactions, which certainly are the best time-wasters in the air.

2008-01-06

Israeli cellphone numbers

I am surprised how many people don't understand my recent gtalk's status message: "No more 054 4818021. Since November, please find me at 05 44818021."

Hint: I used to be a slave [of a mobile phone company]. Now I am a free man!

More on that matter: a super-funny bug in VM's phone system was discovered - it's no longer possible to call 054 numbers which are not Orange. They are directed to the Orange line which then replies "only orange numbers can be called from this line".

Funny story #3: It appears like landline company phones are now also interchangeable. One can move from Bezeq to Hot and still have his 03 number. IZ was trying to move an apartment to another area in Tel Aviv, and was trying to keep his 03. "No" said bezeq, "we cannot relocate to a different station". His only way to keep it was to move to another phone company, and then back to bezeq.