Showing posts with label Misc. Show all posts
Showing posts with label Misc. Show all posts

Sunday, November 01, 2009

Mathematics for Automotive Engineering

Cylinder volume = (π/4) x bore2 x stroke

Displacement = (π/4) x bore2 x stroke x number of cylinders

Displacement of overbore = (π/4) x (bore + overbore)2 x stroke x number
of cylinders

Stroke = displacement/( π/4 x bore2 x number of cylinders)

Compression ratio = (cylinder + chamber volume)/chamber volume

Piston speed in inches per minute = 2 stroke in inches x rpm

Horsepower = (rpm x torque)/5252

Bhp loss = (elevation in feet/1000) x 0.03 x (bhp at sea level)

Horsepower = (mean effective pressure x displacement x rpm)/792,000

Torque = (mean effective pressure x displacement)/150.8

Theoretical cubic feet per minute = (rpm x displacement)/3456

Racing carb cfm = 1.1 x (rpm x displacement)/3456

Center of gravity behind front wheels = (rear wheel weight/overall
weight) x wheelbase

Drive wheel torque = flywheel torque x first gera x final drive x 0.85

Wheel thrust = drive wheel torque/rolling radius

g = wheel thrust/weight

rpm after shift = (ratio shift into/ratio shift from) x rpm before shift

mph = (rpm x tire diameter)/(gear ratio x 336)

tire diameter = 2 x (section width x aspect ratio)/2540 + rim diameter

Actual mph = (new tire diameter/old tire diameter) x indicated mph

Blood alcohol concentration = (ounces x %alcohol x 0.075)/weight — (hours x 0.015)

Saturday, September 06, 2008

Not so Chrome.

from the SANS Institute newsletter (NewsBites).

--Chrome Gets Some Dents
(September 3, 2008)
People have already begun to find vulnerabilities in the beta version of Google Chrome, the company's new web browser. In one scenario involving a flaw in the WebKit engine and another in Java, users could be tricked into downloading executable files. In another scenario, the browser could be crashed when users click on maliciously crafted links.

Proof-of-concept code has been posted for both vulnerabilities.
http://www.informationweek.com/news/internet/google/showArticle.jhtml?articleID=210300297
http://www.scmagazineus.com/Google-Chrome-flaws-come-soon-after-browser-release/article/116251/
http://www.heise-online.co.uk/security/Google-Chrome-beta-comes-with-security-holes--/news/111458

[Editor's Note (Pescatore): Let's see: by my math, if you multiply the security level of consumer-grade software times the security level of beta code, you get a whole mess of vulnerabilities that will be easily exploited. That said, I would love to see more competition in the browser world drive browsers to simpler code bases with more focus on security as the top feature, vs. trying to bundle in email clients and all kinds of other stuff.

(Schultz): For a nice, unbiased view of Chrome security, visit http://www.high-tower.com/blogs/bolcer/

By the way Chrome's EULA still shows
"By submitting, posting or displaying the content you give Google (NSDQ: GOOG) a perpetual, irrevocable, worldwide, royalty-free, and non-exclusive license to reproduce, adapt, modify, translate, publish, publicly perform, publicly display, and distribute any Content which you submit, post, or display on or through, the Services."

Friday, September 05, 2008

Chrome EULA: Google owns all your shit

From a post of my friend, Manoj,
"Google Chrome EULA Claims Ownership of Everything You Create Using Chrome, From Emails to Blog Posts".

http://agarwalmk.spaces.live.com/Blog/cns!780CD8FB86EF8F7C!15133.entry?wa=wsignin1.0