Select Page

Jeff Danner

The Birthday Problem

You may have heard that if you are in a room with 23 people, there is a greater than 50% chance that two people in the room have the same birthday. This is commonly known as the “Birthday Problem.” Most people presented with this information are, at least initially, quite skeptical. Typically what throws people off is that they approach the problem with an incorrect perspective.

Read More

3D Printing Part I: The Technology

For the past several years, 3D printing technology has been garnering quite a few headlines. Unfortunately, as is common for the main-stream media, many of the interesting science elements are left out of these stories. So I figured it was time for a Common Science treatment of this fascinating technology. This week I will discuss what 3D printing is, and next week I will speculate on its potential. The printing process starts by creating a digital 3D model of the object to be assembled in computer code. Next, you decide what material you want to build your object from....

Read More

China, The Canary in the Coal Mine

When I started writing Common Science in 2011, I did not envision devoting so many columns to resource constraint issues. However, every time I listen to the news or read the paper I am assaulted with warning signs of rapidly approaching resource scarcity issues. Many of these stories are set in China. Let me give you some examples. In my column iPads, Priuses, and Neodymium, I discussed the growing importance of rare earth metals(1) in electronic devices and advanced battery technologies. Deposits of these valuable metals are few and far between. Any reasonable assessment of the situation suggests that...

Read More

Checking In On Peak Oil

In last week’s column, The Case of the Missing Propane, I explained how the widespread use of hydraulic fracturing (fracking) of shale oil deposits since 2008 has led to a 30% increase in the production of crude petroleum in the United States. While that statistic makes for snappy headlines, it is not particularly meaningful to the overall world oil supply or the phenomenon known as Peak Oil. If you are not familiar with Peak Oil, I published a column in June of 2011 called Peak Oil in Five Paragraphs or Less. Here are the key points: • Peak Oil...

Read More

The Case of the Missing Propane

Over the past few weeks, I have seen many stories about propane shortages in the United States. As a result of these shortages, prices for propane have nearly doubled from around $2.20 per gallon at the end of last year to over $4.00 per gallon this week. This situation struck me as quite odd. We should be nearly drowning in propane at the moment. So I decided to try to figure out what was going on. As usual, let’s start with the background. Propane is a small, simple hydrocarbon with the chemical formula C3H8. At normal temperatures and pressures,...

Read More

A Tale of Two Spills

On February 2, 2014, a storm water drain at a retired coal-fired power plant near the North Carolina-Virginia border ruptured, which allowed more than 80,000 tons of coal ash to spill into the Dan River. The Dan River is the drinking water source for many communities and is a primary feeder to Kerr Lake Reservoir. This event comes closely on the heels of another coal-industry-related accident, the spill of 4-methylcyclohexane methanol (MCHM) into the Elk River in West Virginia. (Follow this link to my recent column on the events in West Virginia.) These two spills share an important connection:...

Read More

Keystone Pipeline Update

With the recent release of the State Department’s report on the Keystone XL pipeline, I thought would review some of the key issues for this topic. The Keystone XL pipeline is intended to transport diluted bitumen, a low-grade, impure form of crude petroleum, from the oil sands in Alberta, Canada to refineries in Oklahoma and Texas. The essence of the State Department report is that the pipeline project would not have a negative environmental impact because, in its absence, the oils sands would be exploited anyway and transported via railcar. The report further stated, correctly, that rail transport is...

Read More

My First PC Weighed 25 Pounds

My children like to make comparisons between the technology I had growing up and what they have today. In the course of a recent conversation on this topic, it occurred to me that, having been born in 1966, I have lived through the entire evolution of the personal computer and the internet. The internet got its start in the 1960s with government funding through an organization called the Advanced Research Project Agency (ARPA), whose original network was called ARPANet. In time, the project was taken over by the Department of Defense, which changed the name to DARPANet. Advances in...

Read More

West Virginia Chemical Spill

On January the 9th, 2014, 7,500 gallons of a chemical called 4-methylcyclohexane methanol (MCHM) leaked from a Freedom Industries storage tank into the Elk River near Charleston, West Virginia, polluting the drinking water supply for over 300,000 people. The tank had not been inspected by regulators since the early 1990s. The other day a friend asked me if I planned to write a column about this incident. I told her that the whole sad story seemed unremarkable to me, and that I had yet to find an aspect of it to which I thought I could provide a meaningful...

Read More

We Can Afford More Math Textbooks

As an engineer, I have had a lot of math education in my life, everything from multiplication tables to systems of partial differential equations.  I was quite successful in these classes due in part to the good fortune of innate ability, but also, I firmly believe, because for every class I had a textbook of my own filled with helpful explanations and examples. I frequently tutor my children and my friends’ children in math and have being doing so for years. As such, I believe I have sufficient data to make a few valid conclusions. I have no doubt...

Read More
Translate »