Monthly Archives: March 2014

Kepler Planet Finding Probabilities

Posted on 29-March-2014 by mathscinotes

One of my favorite online magazines is +Plus. I was reading an article in +Plus today about how the Kepler satellite finds exoplanets and the article mentioned a simple formula for the probability of Kepler being able to detect a planet. I thought it would be interesting to discuss this formula here because it involves a simple formula that provides insight into cutting-edge science. Continue reading →

Posted in Astronomy | 1 Comment

Discussion of Math Associated with MH370 Search

Posted on 26-March-2014 by mathscinotes

Here are a couple of web sources on how the course of MH370 was determined. CNN Ars Technica Some of these transponder-based, distance analyses reminds me a bit of the Oboe navigation system used during WW2. The Doppler shift work … Continue reading →

Posted in Navigation | Comments Off on Discussion of Math Associated with MH370 Search

6000 Meter Depth Rating on Ocean Search Gear

Posted on 23-March-2014 by mathscinotes

Quote of the Day The sea is notoriously unforgiving, but it reserves its harshest penalties for those who venture beneath its surface. — U.S. Navy veteran A.J. Hill I have been watching the news coverage of the search for the … Continue reading →

Posted in Underwater | 1 Comment

Frost Depth Deeper Than Normal This Winter

Posted on 16-March-2014 by mathscinotes

Quote of the Day Maybe not today..., maybe not tomorrow..., but someday... soon; ... and for the rest of your life ... - Rick Blaine, Casablanca. I was in my home town of Osseo this weekend to do some computer … Continue reading →

Posted in Construction | 1 Comment

Using a D-Size Battery String for a UPS Energy Source

Posted on 15-March-2014 by mathscinotes

Quote of the Day If there is one thing more than another for which I admire you, it is your original discovery of the Ten Commandments. — Thomas B. Reed to the youthful Theodore Roosevelt about his self-righteousness Introduction I … Continue reading →

Posted in Batteries, Electronics | Comments Off on Using a D-Size Battery String for a UPS Energy Source

A Simple Frequency-to-Voltage Converter

Posted on 13-March-2014 by mathscinotes

Quote of the Day We are what we repeatedly do. Excellence, then, is not an act, but a habit. - Aristotle Introduction I often build small electronics projects for use around my home. I recently put together a small sensor … Continue reading →

Posted in Electronics | 41 Comments

Population Occurrence Frequency Math

Posted on 8-March-2014 by mathscinotes

Quote of the Day Do what you can, with what you have, where you are. — Theodore Roosevelt I was reading an article on autism and the article mentioned that autism is much more prevalent in boys than girls. This … Continue reading →

Posted in General Science, Health | Comments Off on Population Occurrence Frequency Math

Paper Mechanism Project I Have to Build

Posted on 2-March-2014 by mathscinotes

I think this interrupted motion paper machine is really interesting. This is on my list for a project. If you want to see other projects like this, got Robert Ives' web site.

Posted in Paper Machines | Comments Off on Paper Mechanism Project I Have to Build

Incredible Mechanical Music Player

Posted on 2-March-2014 by mathscinotes

Take a look at this digitally-created instrument and how it is being played.

Posted in Personal, Uncategorized | Comments Off on Incredible Mechanical Music Player

Schmitt Trigger Design Math

Posted on 2-March-2014 by mathscinotes

I have a home project that requires me to design a Schmitt trigger circuit. There are numerous places on the web where you can find design equations for the Schmitt trigger constructed using an open-drain comparator. Unfortunately, these design equations do not model the output low-level saturation voltage of the comparator and in my application I need to be concerned about this voltage. My objective is to determine formulas for the resistors in the circuit as a function of the various threshold and output voltage levels I require. Continue reading →

Posted in Electronics | 14 Comments