Monthly Archives: August 2013

Engineering Economics The Basics – First Edition

I put another quick book on Amazon. It is the first edition so it is still a little rough BUT you can buy it, look at it and then return it for a refund if you hate it.

Engineering Economics – The Basics shows the typical formulas used in economic analysis with over 55 examples. Subjects such as compounding interest, economic equivalence, internal rate of return and benefit cost ratios are covered.

Engineering Economics – The Basics on Amazon – $1.99

eng econ

Here are a few examples from the book.

Compute the equivalent value of S, by moving the series of $1000, and assuming a 12% interest rate.
Solution: The question asks you to move the three $1000 cash flows to a different location on a timeline. This is what economic equivalence is all about, the series of “S” values is equivalent to the series of $1000, as long as the interest rate stays the same throughout the timeline.

equivalence 1

Based on a benefit/cost ratio, which of the two alternatives given below should be chosen? Use an interest rate of 9% for the analysis.
Hint: First check both alternatives have a benefit/cost ratio greater or equal to one and then calculate an incremental benefit/cost ratio. (Note the formulas used for determining present worth, in this example, may not always be the same ones as shown below.)


Engineers Must Draw a Line on Sustainability

Well look at this editorial that just came out in ENR magazine. I guess I was slightly ahead of the curve. (See previous post)

It is a mild look at sustainability but more engineers are recognizing the importance of maintaining resources for the future.

Still, the bridge is a constant reminder of a question I have been grappling with for some time. What is our responsibility as designers and builders when the entire conception of the project violates principles of sustainable development?

I looked to the American Society of Civil Engineer’s code of ethics for guidance. I already knew that we engineers should act in the best interest of the public, not just the client. And I knew that we should do what’s right, not just follow laws. But I had to look up our sustainability obligations. Turns out, the very first “canon” in ASCE’s code of ethics requires that we “strive to comply with the principles of sustainable development.”

Should the professionals asked to design our pedestrian bridge have pointed out more sustainable options? What if those options require different design expertise? What about professionals asked to design and build a coal-fired powerplant? A 14-bedroom mansion for a bachelor billionaire? A LEED Platinum building, when user needs could be met with a more thoughtful use of existing spaces? If these examples can’t be justified as sustainable, then are those who build them complying with our code of ethics?

Bad Intent Good Engineering

Listening to the news and getting ready to teach a class about engineering ethics, I can’t help but think of all the perverse ways engineering is misused. Should an engineer care about the final use of their designs?

I watched a documentary on the V2 rockets used in the Second World War. The designer, Wernher von Braun, developed the rockets, which caused a great number of casualties, but after the war he worked for the United States, developing the moon program. He even won the national medal of science. Quite a turn around.

Chemical weapons have recently been deployed, I would imagine an engineer helped to facilitate that effort. Since the engineering code mandates the protection of the safety, health and well being of the public, it is hard to imagine how an engineer could reconcile those two opposing points of view. Do you engineers ever wonder about these sorts of thing?

(Don’t sue me Walt Disney)


Boris Vian

Interesting engineer, thanks for the link David.

From Wikipedia,

Boris Vian (French: [bɔʁis vjɑ̃]; 10 March 1920 – 23 June 1959) was a French polymath: writer, poet, musician, singer, translator, critic, actor, inventor and engineer. He is best remembered today for his novels. Those published under the pseudonym Vernon Sullivan were bizarre parodies of criminal fiction, highly controversial at the time of their release. Vian’s other fiction, published under his real name, featured a highly individual writing style with numerous made-up words, subtle wordplay and surrealistic plots. L’Écume des jours (Froth on the Daydream) is the best known of these works, and one of the few translated into English.

Vian was also an important influence on the French jazz scene. He served as liaison for Hoagy Carmichael, Duke Ellington and Miles Davis in Paris, wrote for several French jazz-reviews (Le Jazz Hot, Paris Jazz) and published numerous articles dealing with jazz both in the United States and in France. His own music and songs enjoyed popularity during his lifetime, particularly the anti-war song “Le Déserteur” (The Deserter).


You are never too old

Hal Lasko, better known as Grandpa, worked as a graphic artist back when everything was done by hand. His family introduced him to the computer and Microsoft Paint long after he retired.
Now, Grandpa spends ten hours a day moving pixels around his computer paintings. His work is a blend of pointillism and 8-Bit art.
Meet 98-year-old Hal Lasko, The Pixel Painter.
See more work at