Author Archives: mathscinotes

Correcting Sextant Measurements For Dip

Posted on 21-October-2015 by mathscinotes

I love to read stories of the sea and about the voyages made during the age of sail. I personally have never thought that I would have an opportunity for ocean sailing, but I recently began working with an engineer who is an avid sailor and teacher of sailing. He has sailed all over the world and recently trained another engineer in my group to sail. This newly trained sailor just returned from a trip to Bora Bora, which he found to be enjoyable and the sailing uneventful. Continue reading →

Posted in Naval History, Navigation | 8 Comments

My Phone Stops a Road Rage Incident

Posted on 15-October-2015 by mathscinotes

Quote of the Day Remember to look up at the stars and not down at your feet. Try to make sense of what you see and wonder about what makes the universe exist. Be curious. And however difficult life may … Continue reading →

Posted in Personal | Comments Off on My Phone Stops a Road Rage Incident

Rogue Software Engineers and Responsibility, Accountability, and Authority

Posted on 9-October-2015 by mathscinotes

I have always liked Volkswagen (VW) cars – I actually rebuilt a Beetle engine during a shop class in high-school (Figure 1). My respect for VW took a serious downturn this morning when read the following headline,"Top U.S. VW Exec Blames 'A Couple of Software Engineers' for Scandal". Continue reading →

Posted in Management | 2 Comments

Samsung S5 Field of View

Posted on 5-October-2015 by mathscinotes

I use a Samsung S5 phone for my daily smart phone work. Recently, I have even started to use its camera/video system for some rough measurement work (examples here and here). This work has made me a bit curious about the how the camera subsystem was designed. In this post, I will document a very rough experiment that I performed over lunch today in which I measured the S5 camera's Field of View (FOV). I will also compute the field of view using some information that Samsung provides. The agreement between the results seem reasonable considering my crude approach. Continue reading →

Posted in optics | 5 Comments

My Sister in Math Class

Posted on 30-September-2015 by mathscinotes

My sister posted this video on her Facebook page while stating it described her in math class. There is some truth to this statement. It could also have been used to describe any of her four brothers in nearly every classroom. Continue reading →

Posted in Humor | 5 Comments

Mass-Energy Conversion Example

Posted on 20-September-2015 by mathscinotes

Since 2015 is the 70th anniversary of the end of World War 2 (WW2), C-SPAN has been running a number of oral history interviews with people who worked on the Manhattan Project. I have found these interviews very interesting. You can find them on YouTube and watch them for yourself. Continue reading →

Posted in General Science, History of Science and Technology, Military History | Comments Off on Mass-Energy Conversion Example

Coal Train Daydreams

Posted on 19-September-2015 by mathscinotes

Because of where I work and live, I regularly wait at train-road crossings while coal trains pass in front of me. I get bored while sitting there and I start to think about the amount of coal that is being consumed by one of our local coal-fired power plant known as Sherburne County Generating Station or Sherco for short. I will present my estimates here and show that they agree with the numbers our local power producer is stating for this plant. Continue reading →

Posted in General Science | Comments Off on Coal Train Daydreams

Circular Saw Depth-Of-Cut Formula

Posted on 15-September-2015 by mathscinotes

I recently bought a battery powered, 6.5-inch diameter, circular saw from Milwaukee. I REALLY like this saw. I have been using it at my cabin in Northern Minnesota, a place where dragging around electrical cords is painful. This saw has quickly become one of my workhouse tools. Continue reading →

Posted in Construction, Geometry | 16 Comments

Tree Height Measuring Example

Posted on 10-September-2015 by mathscinotes

I have been testing a number of Android applications that are intended to measure the size of objects knowing their range or vice versa. One application that I have found particularly useful is called Baumhöhenmesser – Tree Height Meter (my translation) – which is an application written by a German developer. I have found this application particularly useful, and I thought I would review its operation here. It is part of a suite of Android applications intended for forestry management. This app makes excellent use of the Android's ability to measure angles. Continue reading →

Posted in General Mathematics, Geometry | 3 Comments

Glacier Melting Math

Posted on 9-September-2015 by mathscinotes

My wife and I are currently on an Alaskan cruise with friends that used to be our neighbors when our children were young. Our cruise ship is the Millennium, which is part of the Celebrity fleet. We are currently moored in Juneau, where we visited the Mendenhall glacier. While at the glacier, I talked with a local Forest Service guide about the rate of glacier melting. I also made a few measurements using my phone and a bit of math then ensued, which I will discuss here. Continue reading →

Posted in Geology, Personal | 2 Comments