A capsule newsletter of science and technology news briefs from NIST written for general audiences; published monthly

April 1998

  Tech Beat

In This Issue:

blueball.gif - 0.93 KScientists Working on Cold Probe for a Warm Heart
blueball.gif - 0.93 KAircraft Safety Measures Include Efforts to End False Fire Alarms
blueball.gif - 0.93 KMeasurements Go 'Down the Tubes'
blueball.gif - 0.93 KComposites Finally Get Some Respect, Economically Speaking
blueball.gif - 0.93 KGlobal Network Technologies Meet the Red Brick School House
blueball.gif - 0.93 KHot Off the Press! Get Your Metric Poster Here!
blueball.gif - 0.93 KTech Trivia

[Credits] [NIST Tech Beat Archives] [Media Contacts] [Subscription Information]

blue.gif - 0.33 K


Scientists Working on Cold Probe for a Warm Heart

According to an old adage, cold hands mean a warm heart. Well now, with a hand from scientists at the National Institute of Standards and Technology, CryoGen Inc. of San Diego, Calif., is closer to developing an ultracold probe to treat rapid-rate heart beats, or heart arrhythmia, which affects some 2 million Americans. Scientists recently achieved the desired cold temperature and produced ice balls of the size required to treat heart arrhythmia.

These irregular heart beats can be present at birth or can arise from damaged tissue after a heart attack. Current treatment includes medication and electrical burning of the damaged tissue. Both methods, however, have drawbacks. The cold-probe method involves inserting a catheter through the large veins leading into the heart. A special refrigerant mixture is then circulated through the catheter to cause the tip to become very cold. The damaged tissue is destroyed by freezing it with ice balls. Balls of 26 millimeters in diameter and weighing 11 grams were created, even better than the desired goals of 10 millimeters and 1.5 to 2.0 grams.

Media Contact:
Fred McGehan (Boulder) (303) 497-3246

blue.gif - 0.33 K


Aircraft Safety Measures Include Efforts to End False Fire Alarms

New Federal Aviation Administration regulations soon will require fire detection systems in virtually all cargo compartments in commercial airliners. The change, to be implemented in the next three years, will triple the number of aircraft required to have fire detection systems. The safety measure could, however, increase airborne false fire alarms threefold. That could happen because virtually all aircraft fire detection systems rely on detection of smoke particles, and airborne contaminates other than smoke particles can trigger the alarm.

The aircraft industry estimates that worldwide there are hundreds of false alarms for every alarm due to actual smoke in the compartment. In the event of an in-flight cargo smoke detector alarm, the flight crew must divert the plane to the nearest suitable, but sometimes unfamiliar, airport. Although the FAA judges an undetected aircraft fire much more dangerous than a flight diversion caused by a false fire alarm, it also wants to minimize the possibility of false alarms. Under a NASA-sponsored program, the FAA has asked National Institute of Standards and Technology fire researchers to look into ways to cut the projected false alarm rates. By the end of the year, NIST will report to the FAA and NASA on new fire detection technologies available and recommend a plan for determining which technologies are best suited to reduced false alarms in aircraft cargo areas.

Media Contact:
John Blair (301) 975-4261

blue.gif - 0.33 K


Measurements Go 'Down the Tubes'

Measurement science has gone down the tubes. But the descent is only temporary--just long enough for National Institute of Standards and Technology researchers to help the U.S. Navy measure the missile tubes encased in the hulls of its submarines.

Preparing for a major upgrade of the vessels' ship-to-shore missile systems, Navy engineers called on NIST measurement experts to evaluate methods for measuring the bore size of existing tubes, which are 7.2 meters (24 feet) long and 0.6 meter (2 feet) in diameter. The upgrade entails removing retaining rings that had been inserted into the tubes for holding Tomahawk missile capsules. The additional space is needed to accommodate the metal capsules that will house the Tomahawk's replacement, the NTACMS, a significantly larger missile.

Accurate measurements of the bare missile tubes, explains NIST precision engineer Steven Phillips, are key to setting the capsule's manufacturing specifications and dimensional tolerances. A mismatch might necessitate dry docking a submarine and reboring its missile tubes--a costly process that the Navy aims to avoid.

Phillips and other members of his team made several suggestions for ensuring the reliability of the Navy's measurement process. To account for uncontrollable influences on accuracy, NIST mathematician Craig Shakarji ran thousands of simulations, resulting in a Navy-adopted procedure for determining the level of uncertainty in bore size measurements.

Media Contact:
Mark Bello (301) 975-3776

blue.gif - 0.33 K


Composites Finally Get Some Respect, Economically Speaking

Composites have a lot of things going for them--these reinforced-resin materials are strong, lightweight and corrosion resistant--but affordable manufacturing for structural applications has not been one of them. Until now. New manufacturing technology, designed and demonstrated with support from the National Institute of Standards and Technology's Advanced Technology Program, now makes composite utility towers economically attractive, too.

Ebert Composites Corp. of San Diego, Calif., reduced the costs in two ways. First, the company designed towers with interlocking joints to enable a "snap-and-build" assembly process that reduces at-site construction time. Then, with ATP support, the company reduced production time by 90 percent by combining pultrusion (a traditional composites manufacturing process) and computer numerical control machining. The advance also reduced labor costs and human error.

Southern California Edison Co., which operates three demonstration towers made by Ebert, says the structures cost about the same as steel towers initially. Moreover, the utility expects to save 66 percent on installation and, because there is no need for regular washing to remove corrosion-causing salt from the nearby ocean, expects to save $700 per tower on annual maintenance. The environmental benefits include reduced magnetic fields and "roadless" tower placement by helicopter.

Media Contact:
Michael Baum (301) 975-2763

blue.gif - 0.33 K


Global Network Technologies Meet the Red Brick School House

Since the earliest years of the personal computer, people have talked of applying this new technology to the classroom, but examples of really effective uses of information technology in education are rare. Even the best instructional software today is quite limited--static, easily outdated, single-point solutions to single needs.

But modern networking technologies promise so much more: intelligent, flexible systems that can call on widely distributed resources across the global net; systems that scale easily from small applications to large, that allow course content to be reused, easily updated and adapted on-the-fly to the needs of the learner; and systems with built-in tools that allow educators and authors to create powerful interactive, multimedia learning vehicles without needing to be experts in programming and software development.

The National Institute of Standards and Technology's Advanced Technology Program has launched a new focused program in Adaptive Learning Systems to support high-risk research and development projects to further these capabilities with new infrastructure technologies based on information networks such as the World Wide Web. The future "adaptive learning systems" envisioned by the new program will reduce costs, improve effectiveness and productivity, and make training and learning more accessible than ever before.

Media Contact:
Michael Baum (301) 975-2763

blue.gif - 0.33 K


Hot Off the Press! Get Your Metric Poster Here!

Four new publications from the Metric Program at the National Institute of Standards and Technology offer lots of fun and useful metric tidbits, from a recipe for metric cookies to definitions of all the fundamental metric units. The NIST Metric Program, which coordinates metric transition activities of all federal agencies, is offering a new poster and three brochures to help educate Americans about the metric system.

A large colorful wall poster defines each of the seven metric base units with information on related metric units and all the metric prefixes from "yocto" to "yotta," plus many common conversions. A color brochure, titled "A Brief History of Measurement Systems," includes a smaller version of the wall poster and tells how measurement systems evolved in early cultures.

The second brochure, "The United States and the Metric System," includes frequently asked questions and answers. A subsection, "Metric in the Kitchen," covers conversions for cooking and includes a metric recipe for chocolate chip cookies. Also available is a style guide on the metric system. Designed for the news media, it is also useful for teachers and others who express metric units in writing. To request copies of these publications, fax your request to the NIST Metric Program, (301) 948-1416. Two of the brochures also are available on the World Wide Web at www.nist.gov/metric.

Media Contact:
Linda Joy (301) 975-4403
blue.gif - 0.33 K

Tech Trivia

With claims for damaged luggage costing more than $1 million annually, rail, train and airline officials, in about 1950, asked the National Bureau of Standards (now NIST) to develop guidelines for suitcases. A good suitcase, an NBS study recommended, should be able to support a 150-pound man standing on its top, sides, or ends for five minutes, and its handle should survive at least 25,000 pickups.

A National Bureau of Standards study begun in 1904 found more than 600 sizes and variations in fire hose couplings. In February 1904, a blaze in Baltimore burned for 30 hours while many volunteers stood by helplessly because their hoses did not fit city hydrants. In 1905, the National Fire Protection Association issued a recommended standard for couplings.

Staff from the National Bureau of Standards (now NIST) served as timers for the President's Cup Regatta power boat races on the Potomac River for at least three decades beginning in 1926. Watches, on loan from commercial manufacturers, were calibrated at NBS on the Friday before the races.

blue.gif - 0.33 K

U.S. Department of Commerce
Technology Administration
National Institute of Standards and Technology

Editor: Linda Joy
HTML conversion: Crissy Wines

Last update: August 12, 1998


 Back to NIST Home Page Back to Top Graphic