Archive

Archive for June 25, 2011

Japan’s Stealth Fighter Gambit

June 25, 2011 Comments off

the-diplomat

Tokyo seems poised to spend billions developing the country’s first homegrown stealth warplane. But is the Shinshin really meant for military service?

Advertisements

Power-grid experiment could confuse electric clocks

June 25, 2011 Comments off

msnbc

Traffic lights, security systems and computers may be affected by frequency change as well
Chris Carthart

Charles Krupa  /  AP

A UPS delivery man in South Boston wheels packages past a store window featuring clocks at Quincy Market in Boston.

WASHINGTON — A yearlong experiment with America’s electric grid could mess up traffic lights, security systems and some computers — and make plug-in clocks and appliances like programmable coffeemakers run up to 20 minutes fast.

“A lot of people are going to have things break and they’re not going to know why,” said Demetrios Matsakis, head of the time service department at the U.S. Naval Observatory, one of two official timekeeping agencies in the federal government.

Since 1930, electric clocks have kept time based on the rate of the electrical current that powers them. If the current slips off its usual rate, clocks run a little fast or slow. Power companies now take steps to correct it and keep the frequency of the current — and the time — as precise as possible.

The group that oversees the U.S. power grid is proposing an experiment that would allow more frequency variation than it does now without Read more…

Case Study: Tsunami in Seaside, Oregon

June 25, 2011 1 comment

carleton

Oregon Coast’s Vulnerability

tsunami map Recent research suggests that a Cascadia Subduction Zone earthquake could create tsunami waves that impact over 1,000-km of coastline in the U.S. and Canada. Source: USGS

The northwestern coast of Oregon is susceptible to both local and far-field tsunamis. The Cascadia Subduction Zone, where the eastward moving Juan de Fuca plate meets the westward moving North American Plate, is just off the Pacific Northwest coast of the United States and Canada. It is a 750-kilometer long fault zone. This area is very active tectonically, and therefore has the potential to produce large earthquakes and possibly, subsequent tsunamis. This subduction zone is thought to have last ruptured in 1700.

Additionally, far-field earthquakes throughout the Pacific are also capable of spawning tsunamis that could eventually reach the Oregon coast. Historical records show that since 1812, about 28 tsunamis with wave heights greater than one meter have reached the U.S. west coast. The March 1964 “Good Friday” earthquake created the most devastating of these tsunamis. The epicenter of this earthquake was near Anchorage, Alaska. The tsunami that followed this earthquake reached coasts all along the western U.S. within six hours. Cannon Beach, a small coastal community in northwestern Oregon was inundated during Read more…