Dr. Dobb's Journal April 2002
Researchers at Sandia National Labs have fabricated a bicycle-chain-like microchain that's so small that each link can be placed on a human hair. The distance between chain-link centers is 50 microns, whereas the diameter of a human hair is approximately 70 microns. The microchain makes it possible to drive multiple microelectromechanical devices from a single motor situated at a distance, rather than having multiple motors, thereby saving space. According to Sandia technician Ed Vernon (who received a patent for the silicon microchain), applications include powering microcamera shutters and the like. For more information, see http://www.sandia.gov/media/NewsRel/NR2002/chain.htm.
One man's "trustworthy computing" is another's "high-dependability computing." By whatever name, the goal is the same — to develop more dependable software. To that end, Carnegie Mellon University's School of Computer Science is launching its multidisciplinary, multiinstitutional High-Dependability Computing Program. Funded by a $23 million NASA grant, initial testbed projects will likely include advanced networking architectures for the International Space Station and research to improve air-traffic control. The High-Dependability Computing Consortium, which includes Carnegie Mellon, MIT, the University of Maryland, University of Southern California, University of Washington, the University of Wisconsin, and corporate partners, was formed to research how complex software can be more reliable and secure.
According to the 2002 Lemelson-MIT Invention Index, an annual survey of Americans' perceptions about inventing and innovating, the invention of the personal computer was much more significant than television, at least according to U.S. teenagers. When asked to select the most important invention of the 20th century from among five choices — personal computers, pacemakers, television, wireless communications, and water purification — nearly 32 percent of the teens chose the PC, 26 percent the pacemaker, 18 percent selected wireless communications, and 10 percent TV. Alternatively, 34 percent of adults said the pacemaker was the most important invention, 26 percent said the PC, 15 percent selected TV, and 11 percent water purification. The 2002 survey was conducted from a representative sample of 1012 adults and 500 teenagers. For more information, see http://web.mit.edu/invent/www/index00.html.
Technology originally designed for remotely updating network equipment has been repurposed to combat cellular phone theft. The CoolRunner-II, a reconfigurable logic chip from Xilinx (http://www.xilinx.com/), makes it possible for operators to remotely disable stolen or lost mobile phones by shutting down the keypad. Alternatively, the chip can reactivate the phone if and when it is returned to its rightful owner.
A message to be transmitted into space may test the ability of SETI researchers to comprehend alien communications. Canadian physicists Yvan Dutil and Stephane Dumas have posted an "output stream," which they intend to broadcast into deep space. The message is written in binary format and contains deliberate distortion indented to simulate the kind of deterioration a signal could suffer as it travels through space. The pair hope that if human scientists can decode the message, then alien beings will also be capable of understanding it.
From the feedback Dumas and Dutil have received, their encoding scheme works correctly as long as the noise level is under 14 percent. The two are now working on a C/C++ program, to assist with the decoding of any similar broadcasts. The tool incorporates algorithms of signal analysis, cryptography, and computational linguistics.
This is the second transmission that Dumas and Dutil have designed. The first message was a series of pictures annotated with invented symbols and sponsored by Team Encounter (http://www.teamencounter.com/), which sells "Space Travel Kits" offering the public the chance to send their names and personal messages into space.
The company intends to broadcast the new message within a few months, probably through a laser beam, and launch a spacecraft in early 2004. The two messages are available at http://www3.sympatico.ca/stephane_dumas/CETI/.
According to a team of Korean and U.S. researchers, light has been brought to a complete standstill inside a crystal. Even more significantly, the stored energy of the light pulse can be reemitted later, effectively allowing the pulse to be stored within the solid. These stationary light pulses could be used for data storage in a quantum computer, eliminating the need to maintain individual atoms in specific states.
In an experiment performed at the Massachusetts Institute of Technology and at the U.S. Air Force Research Laboratory, researchers used a crystal of yttrium-silicate doped with atoms of praseodymium — a material already used in high-density optical data storage — to trap the light pulse.
The technique used to halt the light was developed earlier this year by Harvard University researchers, who successfully trapped light within a super-cooled gas of sodium atoms. Essentially, a laser beam can render the electrons within the substance incapable of jumping up to higher energy levels. A second laser beam is then used to "couple" the light to the atoms. If the coupling laser is correctly tuned, the light will slow as the laser becomes dimmer and come to rest when it is switched off. The pulse then resumes moving when the coupling laser is restored.
The Association for Computing Machinery (ACM) has awarded the 2001 A.M. Turing Award — the "Nobel Prize of Computing" — to Ole-Johan Dahl and Kristen Nygaard for their work in the invention of object-oriented programming. Dahl and Nygaard, who are professors (emeriti) at the University of Oslo, developed their OOP concepts at the Norwegian Computing Center in the 1960s. Object-oriented languages they are credited with developing include Simula I, the discrete event simulation language, and the more general-purpose Simula 67. Nygaard also invented the Beta language. The Turing Award includes a $25,000 prize. For more information, see http://www.acm.org/awards/taward.html.