Double Feature:
Greatest Hits from the KYMAA
Two of our faculty gave talks at the Kentucky Section Meeting of the
Mathematical Association of America this spring, and have agreed to reprise
those for anyone who might have missed them the first time around.
Friday, 4/20
3:05, MEP461
Wavelets by Lifting
Roger Zarnowski
Professor, Mathematics and Statistics
Northern Kentucky University
Abstract:
Discrete Wavelet Transforms (DWTs) are commonly developed through the use of
filter banks, which are in turn analyzed using Fourier series. An alternative
approach called lifting was introduced by W. Sweldens in 1996. This method of
constructing DWTs can be advantageous in introductory courses and also has some
computational benefits. I will present an overview of the lifting method and
briefly discuss its utility in both instruction and applications.
T. R. Hollcroft's Problem
Chris Christensen
Professor, Mathematics and Statistics
Northern Kentucky University
Abstract:
On Saturday 25 November 1944, Wells College mathematician T. R. Hollcroft
presented a combinatorial problem at the 51st Annual Meeting of the AMS in
Chicago. A later declassified Navy document states: "when he presented his
findings in a paper before the Society, some of the members openly questioned
that any possible use for the data would ever be found. But back in GYP-1 [the
section of Naval Communications dealing with the Japanese naval cipher JN-25]
it became the Bible of the small Key Room group who were laboring around the
clock on 62 [a new version of JN-25]." In this presentation we will consider
Hollcroft's problem, see how Hollcroft's tables were constructed and how they
were used operationally, and speculate why Hollcroft received the problem.