Author Archives: mathscinotes

Australian Phone Line Impedance Math

Posted on 22-December-2013 by mathscinotes

Quote of the Day The time to reef the sails is before the storm is upon you. — Old sailing aphorism Introduction I am doing some work with international phone circuits and I noticed that the Australian government has test … Continue reading →

Posted in Electronics | 3 Comments

The Old Two Coat Trick

Posted on 19-December-2013 by mathscinotes

Quote of the Day Everything we call real is made up of things that cannot be real. — Niels Bohr I had a déjà vu moment this morning. One of my staff members was looking for another staff member and … Continue reading →

Posted in Management | 4 Comments

Two-Resistor Thermistor Linearizer

Posted on 18-December-2013 by mathscinotes

Quote of the Day Ability is of little account without opportunity — Napoleon Bonaparte Introduction I was asked a question today about how to design a two-resistor thermistor linearization circuit. This very brief post is intended to provide the background … Continue reading →

Posted in Electronics | 3 Comments

Ballistic Coefficient Rule of Thumb Example

Posted on 13-December-2013 by mathscinotes

Quote of the Day Wisdom and experience are built from bricks made from the mud of failure. — Mike Blue I am working on a ballistic simulator and I was looking for some test data. While hunting up some data, … Continue reading →

Posted in Ballistics | 4 Comments

World War 2 Submarine Hull Thickness Math

Posted on 12-December-2013 by mathscinotes

Quote of the Day How are the children? — Masai warrior greeting, intended to ensure that the warriors always keep their number one priority in mind. I was reading a blog post on Gizmodo that did a bit of math … Continue reading →

Posted in Military History, Naval History | 2 Comments

An Example of Misusing Thermal Resistances

Posted on 11-December-2013 by mathscinotes

Quote of the Day Being defeated is often a temporary condition. Giving up is what makes it permanent. — Marilyn vos Savant In my previous post, I provided some definitions of thermal resistances and thermal characteristics. In this post, I … Continue reading →

Posted in Electronics | Comments Off on An Example of Misusing Thermal Resistances

Compact Thermal Models for Electrical Components

Posted on 11-December-2013 by mathscinotes

I am an electrical engineer and not a mechanical engineer. As such, I depend on electronic packaging professionals to provide me answers to my thermal questions at work. However, I am curious about how the packaging folks estimate the temperatures of my parts because it affects how my team designs products. This blog post documents my early self-education on how the thermal analysis of electronic components is performed. This post will provide the background necessary for more detailed posts in the future. Continue reading →

Posted in Electronics | 3 Comments

Difficulty of Viewing Dwarf Planets

Posted on 8-December-2013 by mathscinotes

I was listening to an astronomer on the radio answering questions on viewing stars and planets. A question was asked about why we can have beautifully detailed photos taken from Earth of distant astronomical objects (e.g. Crab Nebula) but we cannot seem to obtain detailed photos of objects in our solar system like Pluto (Figure 1). The astronomer answered that the distant objects are huge and that we view them from Earth as having a larger viewing angle than a minor planet in our solar system. I thought it might be interesting to look at the relative viewing angle of these two objects when viewed from Earth. Continue reading →

Posted in Astronomy | 1 Comment

My Borg Name is "1 of 13"

Posted on 8-December-2013 by mathscinotes

I work for a small company that has 13 employees named "Mark", which is my first name. It is common for me to be in meetings with three "Marks" present. I have had as many as six "Marks" in a meeting. This makes using our first names difficult, and I usually go by my last name. This system works, but does sound a bit gruff to people from outside the company who here our meetings. Continue reading →

Posted in Personal | Comments Off on My Borg Name is "1 of 13"

T-Shirt and Cotton Fiber Math

Posted on 7-December-2013 by mathscinotes

I was listening to a radio program called Planet Money today that was discussing how how intricate the infrastructure is for making something as simple as a T-shirt. They were making a T-shirt that they would sell to raise money to help the garment workers in Bangladesh (see Figure 1). The money required for this effort was raised on Kickstarter. Continue reading →

Posted in General Mathematics | 3 Comments