Monthly Archives: January 2013

Age Distribution of US Health Care Expenditures

Posted on 25-January-2013 by mathscinotes

I have been wondering why US health care costs are so high. I just read this report that claims that the US spends a far greater percentage of its health care dollars on the elderly than other countries. I decided to plot the data from the report myself to make viewing the data a bit easier -- see Figure 1. The expenditures are normalized to the costs for people in the 50 to 64 year old age range (arbitrarily given a value of 1 unit). Continue reading →

Posted in Financial | 4 Comments

Great Article on Recreating Shackleton's Whiskey

Posted on 19-January-2013 by mathscinotes

While I am not a drinker, I do admire the impressive technology that Scottish distillers used to duplicate the lost recipe for Shackleton's whiskey. They were even able to identify where the peat used in its formulation came from. Continue reading →

Posted in General Science | Tagged | Comments Off on Great Article on Recreating Shackleton's Whiskey

Fond Memories of Fast-Moving Milk Bottles and Toy Boats

Posted on 19-January-2013 by mathscinotes

Last night on "How It's Made" they were showing machines filling bottles with a beverage. This show stimulated my memories from first-grade when I was shown a 16mm movie about how milk came to our door every morning. I still can remember almost every detail of this movie. The story started with a cow eating grass and ended with a bottle of milk on a kitchen table. What really caught my eye was the filling of the milk bottles by machines. It seemed like magic the way the bottles were put into a fast-moving row, filled while moving in a circle, and then capped. Continue reading →

Posted in General Science, Osseo, Personal | 1 Comment

The Joys of Electrostatic Discharge

Posted on 7-January-2013 by mathscinotes

I had to laugh at this Youtube video this morning. This poor guy shows you exactly how NOT to handle hardware during ElectroStatic Discharge (ESD) tests. Continue reading →

Posted in Electronics | 3 Comments

Parabolas and Avalanche Photodiodes

Posted on 6-January-2013 by mathscinotes

During a meeting recently, a vendor was discussing the need for performing production calibration testing that required fitting a parabola to the data from an optical sensor called an Avalanche PhotoDiode (APD) (Figure 1). I recalled this comment while reviewing a test report this morning where I saw a parabola appear in an APD test report from an optical physicist in my group. I realized that our physicist and this vendor were working in related areas. It was an excellent test report that covered both the theoretical and experimental aspects of the subject. It also seemed like a good topic for this blog. Continue reading →

Posted in Electronics | Comments Off on Parabolas and Avalanche Photodiodes

Battery Failure Rates and Continuously-Compounded Interest

Posted on 2-January-2013 by mathscinotes

While performing some routine reliability analysis, I noticed that there is a similarity between battery aging and continuously-compounded interest calculations. I had not noticed this similarity before, and I thought I would document it here.

Figure 1 shows a common lead-acid battery. This chemistry is my focus in this post. Other chemistries will behave similarly, but the constants involved will differ. I will be assuming that the failure rate of the battery is described by the Arrhenius equation. Continue reading →

Posted in Batteries, Electronics | 1 Comment