Problem 3E

The article “Influence of Penetration Rate on Penetrometer Resistance” (J. Oliveira, M. Almeida, et al., Journal of Geotechnical and Geoenvironmental Engineering, 2011:695–703) presents measures of penetration resistance, expressed as a multiple of a standard quantity, for a certain fine-grained soil. Fifteen measurements taken at a depth of 1mhad a mean of 2.31 with a standard deviation of 0.89. Fifteen measurements taken at a depth of 2m had a mean of 2.80 with a standard deviation of 1.10. Can you conclude that the penetration resistance differs between the two depths?

Leslie Ogu CSCI 4531 09/20/2016 - Chapter 21: Public-Key Encryption and Message Authentication Secure Hash Algorithm ● SHA was originally developed by NIST ● Published as FIPS 180 in 1993 ● Was revised in 1995 as SHA-1 ○ Produces 160-bit hash values ● NIST issued revised FIPS 180-2 in 2002 ○ Adds 3 additional versions of SHA ○ SHA-256, SHA-384, SHA-512 ○ With 256 / 384 / 512-bit hash values ○ Same basic structure as SHA-1 but greater security ● In 2005, NIST announced the intention to phase out approval of SHA-1, and move to a reliance on the other SHA version by 2010 SHA Comparisons on slides N 1024 bits diagram in slides SHA-3 ● SHA-2 shares same str