Library@Kendriya Vidyalaya Pattom

Where Minds meet and Ideas pop up !

How to use your laptop to locate an earthquake

earthquake-laptop

Sep 25th 2008
From The Economist print edition

Courtest: The Economist

IF YOU drop your laptop computer, a chip built into it will sense the acceleration and protect the delicate moving parts of its hard disk before it hits the ground. A group of researchers led by Jesse Lawrence of Stanford University are putting the same accelerometer chip to an intriguing new use: detecting earthquakes. They plan to create a network of volunteer laptops that can map out future quakes in far greater detail than traditional seismometers manage.

Seismometers are large, expensive beasts, costing $10,000 or more apiece. They are designed to be exquisitely sensitive to the sort of vibrations an earthquake produces, which means they can pick up tremors that began halfway around the world. By contrast, the accelerometer chips in laptops, which have evolved from those used to detect when a car is in a collision and thus trigger the release of the airbags, are rather crude devices. They are, however, ubiquitous. Almost all modern laptops have them and they are even finding their way into mobile phones. The iPhone, for example, uses such a chip to detect its orientation so that it can rotate its display and thus make it easily readable.

On its own, an accelerometer chip in a laptop is not very useful for earthquake-detection, as it cannot distinguish between a quake and all sorts of other vibrations—the user tapping away at the keyboard, for example. But if lots of these chips are connected to a central server via the internet, their responses can be compared. And if a large number in a particular place register a vibration at almost the same time, it is more likely to be an earthquake than a bunch of users all hitting their space bars. To exploit this group effect, Dr Lawrence’s Quake-Catcher Network (QCN) employs the same software that is used by the SETI@home project, which aggregates computing power from hundreds of thousands of volunteer computers around the world to analyse radio-telescope signals for signs of extraterrestrial intelligence.

Dr Lawrence and his colleagues have already demonstrated that the QCN works. It detected a quake near Reno, Nevada, in April, and one near Los Angeles in July. Merely detecting a quake, however, is not the point. Seismometers can do that. To be useful, the QCN needs to be able to do things that seismometers cannot.

One of those things is to measure the maximum amount of ground shaking. The sensitivity of seismometers means that strong signals would damage them if they were not designed to “clip” such signals when they exceed a certain threshold. The price paid is that information about strong, nearby earthquakes is lost. Laptop accelerometers are more robust. Though they cannot, if in America, tell you anything about an earthquake in China, they can sometimes do better than conventional kit when measuring local quakes.

The network’s second benefit is of sheer numbers. This should allow the construction of far more detailed maps of the up-and-down and side-to-side motions induced by earthquakes. These vary a lot from quake to quake, and that means the damage done by a quake of any given strength is also variable. A better understanding of how movement and damage relate might help both building design and town planning in earthquake zones.

Of course, for that to work, you have to know where each laptop was at the moment of the quake. Ideally, this information would come from a Global Positioning System device fitted within the laptop, but few computers have them at the moment. In their absence, information automatically supplied about the site of the nearest router (a network device that computers use to connect to the wider internet) gives a rough location. This is imperfect, but pooling the data from lots of laptops means that location errors can be detected statistically and erroneous data discarded.

If that can be done quickly enough, the QCN could bring a third—and most valuable—benefit: warning. The speed of internet communication, coupled with a scheme for uploading data from each computer at brief intervals, means that Dr Lawrence’s network could issue an earthquake warning within seconds. That is faster than traditional seismometer networks, which update less regularly, and, above all, is much faster than seismic waves travel. Warnings could thus be broadcast to places the earthquake waves had not yet reached, giving people vital time to find a place of refuge.

At the moment, the QCN has about 1,500 participating computers. But, as happened with SETI@home, the researchers expect numbers to grow once knowledge of the project spreads: qcn.stanford.edu, for those who want to join in the fun.

Filed under: Article of the Week, ,

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Live updates

Library@KV Pattom

Dear Visitor,

This is the official Blog of Library @ Kendriya Vidyalaya Pattom, launched in September 2007. Explore the site, you will get a complete picture of all offline and online resources available and services provided by the Library. Here is a friend, who will help you to find, evaluate and use the right information at right time.

You are the Visitor, Number

  • 5,087,234

5 Million Hits and counting..

Thank you all for making this blog a great success.

Upcoming Events

No upcoming events

KVS Innovations and Experimentations Award 2010

"Library Junction" won the KVS Innovations and Experimentation Award 2010.

All India Competition on Innovative Practices and Experiments in Education for Schools and Teacher Education Institutions 2010-’11

Library Junction won the "All India Competition on Innovative Practices and Experiments in Education for Schools and Teacher Education Institutions 2010-'11" conducted by NCERT.

Visit your Library

Browse Books and Periodicals. Read Newspapers. Pick a New Book from the 'New Arrivals' rack. Search the Internet and the OPAC. Refer for assignments and projects. Suggest a book. Ask a question.Write your comments. And more...Visit the Library Today itself. You are most welcome.

Telephone Reference

+91 9447699724 (Librarian)

E-mail Reference

mail your reference questions to librarykvpattom@gmail.com

Ask the Librarian

“Billion beats:the pulse of India”

The fortnightly e-paper uplinked to www.abdulkalam.com. To visit click the link "E-paper" on Web directory

Website of the Week

http://www.bbc.co.uk/ahistoryoftheworld/

Archives

RSS This day in History

  • Pompey defeated by Julius Caesar at the Battle of Pharsalus: 9 August 48 - This Day in History
    During the Roman Civil War of 49–45 , Julius Caesar's troops on this day in 48 decisively defeated the army of Pompey at the Battle of Pharsalus, causing Pompey to flee to Egypt, where he was subsequently murdered.More Events on this day:1945: The second atomic bomb dropped on Japan by the United States in World War II struck the city of Nagasaki.1 […]
  • Amedeo Avogadro: Biography of the Day
    Amedeo AvogadroBorn this day in 1776, Amedeo Avogadro of Italy showed that, under controlled conditions of temperature and pressure, equal volumes of gases contain an equal number of molecules—what became known as Avogadro's law.
  • Concise Encyclopedia Book and CD-ROM: Special Price from The Britannica Store
    For RSS subscribers The Britannica Store presents a special 20% discount on the Concise Encyclopedia and free CD-ROM. This thoroughly revised and expanded edition of Britannica's most popular publication worldwide is a one-volume encyclopedia containing 28,000 articles accompanied by colorful photographs, diagrams, maps, and flags. The Britannica Concis […]

Recommendations

Library Bookmark

Be a Fan of Library on Facebook

e-reading hub @ Your Library

Face a Book Challenge

RSS KV News Digest

  • An error has occurred; the feed is probably down. Try again later.

Reader of the Month (September 2016)

Sruthi S., VII A

Learn anything freely with Khan Academy Library of Content

A free, world-class education for anyone, anywhere.

Interactive challenges, assessments, and videos, on any topic of your interest.

It’s My Library: Share your Bookfies, Libfies and all Library Stories

Enter your email address to follow this blog and receive notifications of new posts by email.

Join 5,661 other followers

Face a Book: The Reading Challenge

InfoLit India: Information Literacy Project for Young Learners

Subscribe SMS updates

Send: ON Library_KVPattom to 9870807070

‘School Libraries Rocks’ ; International Bookmark Exchange Programme 2015, with Croatia

CBSE Toll Free Tele/Online Helpline

Students can call 1800-11-7002 from any part of the country. The operators will answer general queries and also connect them to the counselors for psychological counseling. On-line counseling on: director.edusat@rediffmail.com, mcsharma2007@rediffmail.com

Child Line (1098)

CHILDLINE 1098 service is a 24 hour free emergency phone outreach service for children in need of care and protection.

Population Stabilization in India Toll Free Helpline

Dial 1800-11-6555 for expert advice on reproductive, maternal and child health; adolescent and sexual health; and family planning.

Quick Answers

CONTACT

S.L.Faisal, Librarian, Kendriya Vidyalaya (Shift-I) Pattom, Thiruvananthapuram-695 004, Kerala, India. Mail: librarykvpattom at gmail.com
%d bloggers like this: