Statistics

Continuously Variable

The t-test assesses whether the means of two groups are statistically different from each other.
T-Test explanation
matlab t-test commands
nice explanations on the Two tailed t-test

Enumeration Data

very nice example of Chi Square (Contingency Table)
Explanations of Chi Square
Contingency Table (Page 158)
soft to calculate Contingency table using Fishers test
the online calculator used to calculate the Fishers results
Chi-Square Satistics explanations

Overlapping Distributions

Discussion on the topic
Cohens value, which seem to be proportional to overlapping
Normal Distribution Overlapping Another

Translational Hard Stop

Simulating a wall as an elastic barrier.
[http://www.mathworks.com/access/helpdesk/help/toolbox/physmod/simscape/ref/translationalhardstop.html]

How to Simulate a Clutch

Zero Crossing Problem is covered :
[http://www.mathworks.com/company/newsletters/digest/2008/may/friction.html]

Motor Related Calculations

[http://www.micromo.com/n390432/n.html]

Inertia Calculations:

Cylinder [http://hyperphysics.phy-astr.gsu.edu/HBASE/icyl.html#icyl2]
Material Weight Calculator [http://www.onlinemetals.com/calculator.cfm]

ODE

Very nicely written guide to solving ODE [http://www.physics.utoronto.ca/~poptor/Com00/ODEGuide.pdf]
Good explanations of ODE and examples (damping !) [http://www.intmath.com/Differential-equations/8_2nd-order-DE-damping-RLC.php]