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09.07
Washington
Technology Digest
Compiled
By IEEE-USA Staff
The following is a recap of new
and notable developments in electrical
engineering and computer or information
technology emerging from the federal government
in August and September.
Construction Begins On
First-Of-Its-Kind Advanced Clean Coal Electric
Generating Facility
On 10 Sept., representatives of
the U.S. Department of Energy (DOE), Southern
Company, KBR Inc. and the Orlando Utilities
Commission (OUC) broke ground for construction
of an advanced 285-megawatt integrated
gasification combined cycle (IGCC) facility near
Orlando, Fla. Based on Integrated Gasification (TRIGTM)
technology, the new generating station will be
among the cleanest, most efficient coal-fueled
power plants in the world.
TRIGTM offers a simpler, more
robust method of producing power than most
existing coal-gasification technologies. It
works by converting coal into synthetic gas for
generating electricity, while significantly
reducing emissions of sulfur dioxide, nitrogen
oxides and mercury. It also will produce 20-25
percent less carbon dioxide emissions the
existing pulverized coal plants and consume
approximately half the water required by a
pulverized coal plant. TRIGTM was developed by
Southern Company at the Power Systems
Development Facility in Wilsonville, Ala.,
through its partnership with DOE and KBR. It is
a superior coal-gasification method that is both
proven and practical for producing power,
chemicals and transportation fuels from coal
with less environmental impact. TRIGTM easily
handles the high-moisture, high-ash coals that
account for more than half of the world’s vast
coal reserves. For more information, see:
www.doe.gov/news/5474.htm
New Fabrication Technique For
Nano-Materials
According to the National
Science Foundation, an innovative and
inexpensive way of making nanomaterials on a
large scale has resulted in novel forms of
advanced materials that pave the way for
exceptional and unexpected optical properties.
The new fabrication technique, known as soft
lithography, or SIL, offers significant
advantages over existing techniques, including
the ability to scale-up the manufacturing
process to produce devices in large quantities.
The research, funded by the
National Science Foundation (NSF) and led by
Teri Odom of Northwestern University, appears as
the cover story in the September 2007 issue of
Nature Nanotechnology. The optical
nanomaterials in this research are called 'plasmonic
metamaterials' because their unique physical
properties originate from shape and structure
rather than material composition only. Two
examples of metamaterials in the natural world
are peacock feathers and butterfly wings. Their
brightly colored patterns are due to structural
variations at the hundreds of nanometers level,
which cause them to absorb or reflect light.
Through the development of a new
nanomanufacturing technique, Odom and her
co-workers have succeeded in making gold films
with virtually infinite arrays of perforations
as small as 100 nanometers--500-1000 times
smaller than a human hair. On a magnified scale,
these perforated gold films look like Swiss
cheese except the perforations are well-ordered
and can spread over macroscale distances. The
researchers' ability to make these optical
metamaterials inexpensively and on large wafers
or sheets is what sets this work apart from
other techniques.
For more information, see:
www.nsf.gov/news/news_summ.jsp?cntn_id=110041&org=olpa&from=news
Dark Web Helps Identify And
Track Terrorists
Terrorists and extremists are
using the Internet to recruit new members,
spread propaganda and plan attacks across the
world. Funded by the National Science Foundation
and other federal agencies, Hsinchun Chen and
his Artificial Intelligence Lab at the
University of Arizona in Tucson have created the
Dark Web project, which aims to systematically
collect and analyze all terrorist-generated
content on the Web.
Using Web spidering, link
analysis, content analysis, authorship analysis,
sentiment analysis and multimedia analysis, Chen
and his team can find, catalogue and analyze
extremist activities online. According to Chen,
scenarios involving vast amounts of information
and data points are ideal challenges for
computational scientists, who use the power of
advanced computers and applications to find
patterns and connections where humans can not.
One of the tools developed by
Dark Web is a technique called Writeprint, which
automatically extracts thousands of
multilingual, structural, and semantic features
to determine who is creating 'anonymous' content
online. Writeprint can look at a posting on an
online bulletin board, for example, and compare
it with writings found elsewhere on the
Internet. By analyzing these certain features,
it can determine with more than 95 percent
accuracy if the author has produced other
content in the past. The system can then alert
analysts when the same author produces new
content, as well as where on the Internet the
content is being copied, linked to or discussed.
According to NSF, Dark Web is
producing tangible results in the global war on
terror. The project team recently completed a
study of online stories and videos designed to
help train terrorists in how to build improvised
explosive devices (IEDs). Understanding what
information is being spread about IED methods
and where in the world it is being downloaded
can improve countermeasures that are developed
to thwart them.
For more information, see:
www.nsf.gov/news/news_summ.jsp?cntn_id=110040&org=NSF&from=news
NIST Measures Challenges For
Wireless In Factories
Factories have much to gain from
wireless technology, such as robot control, RFID
tag monitoring, and local-area network (LAN)
communications. Wireless systems can cost less
and offer more flexibility than cabled systems.
But factories, such as auto production plants,
are challenging environments for wireless
systems, as verified by tests conducted recently
by the National Institute of Standards and
Technology (NIST). Industrial plants can be
highly reflective environments, scattering radio
waves erratically, and interfering with wireless
transmissions, hindering the ability of the auto
industry and other manufacturing sectors to take
full advantage of wireless networking.
In a partnership with the U.S.
Council for Automotive Research (USCAR), NIST
plans to develop a statistical representation of
the radio propagation environment of a
production floor as a basis for developing
standards to pre-qualify wireless devices for
factories. NIST researchers conducted the
initial tests at an auto assembly plant in
August 2006, and completed additional tests this
month at an engine plant and a metal stamping
plant.
The manufacturing plants that
NIST tested were crowded with stationary and
mobile metal structures, such as fabrication and
testing machinery, platforms, fences, beams,
conveyors, mobile forklifts, maintenance
vehicles and automobiles in various stages of
production. NIST monitored frequencies below 6
gigahertz (GHz) for 24-hour periods to
understand the background ambient radio
environment. This spectrum survey showed that
interference from heavy equipment (“machine
noise”) can impair signals for low-frequency
applications such as those used to in some
controllers on the production floor. A detailed
analysis of a common wireless LAN frequency band
(channels from 2.4 to 2.5 GHz) found heavy,
constant traffic by data transmitting nodes,
wireless scanners and industrial equipment. And
signal-scattering tests showed the potential for
high levels of “multipath” interference, where
radio signals travel in multiple complicated
paths from transmitter to receiver, arriving at
slightly different times.
NIST researchers will use these
data in studies aimed at pre-qualifying wireless
devices for use in industrial environments. In
the meantime, NIST researchers have identified a
number of steps that can be taken to minimize
radio interference on the factory floor,
including use of licensed frequency bands where
possible, and restrictions on use of personal
electronics in high-traffic frequency bands such
as 2.4 GHz. Other suggestions include installing
absorbing material in key locations, use of
wireless systems with high immunity to
electromagnetic interference, use of equipment
that emits little machine noise, and use of
directional antennas to help mitigate multipath
interference when transmitter and receiver are
close together.
New NIST Calibration Service
Promises More Reliable Power Grids
Although it sounds like Star
Trek technology, a new calibration service for
phasor measurement units (PMUs) offered by the
National Institute of Standards and
Technology (NIST) with support from the U.S. Department of Energy
is actually intended for operators of America’s
electrical power grid. The new NIST service
provides calibrations for the instruments that
measure the magnitude and phase of voltage and
current signals in a power system — a combined
mathematical entity called a phasor — and report
the data in terms of Coordinated Universal Time
(UTC, also known as “the official world atomic
time”).
Use of absolute time enables
measurements called phase angles taken at one
location on a power grid to be comparable to
others across different systems. Phase angles
and their derivations allow grid managers to
know the operating condition of their portion of
the system and determine if action is needed to
prevent a power blackout.
The new NIST calibration service has already
yielded two additional benefits. First, a major
PMU manufacturer reports that using the
calibrations during the manufacture of its
instruments has improved their accuracy by a
factor of five. Secondly, some PMUs that have
been calibrated using the NIST service have
revealed incompatibilities in the message format
they send out, leading to corrections that have
improved interoperability between PMUs across
power grids.
Nanoscale Blasting Adjusts
Resistance In Magnetic Sensors
A new process for adjusting the
resistance of semiconductor devices by carpeting
a small area of the device with tiny pits, like
a yard dug up by demented terriers, may be the
key to a new class of magnetic sensors, enabling
new, ultra-dense data storage devices. The
technique demonstrated by researchers at the
National Institute of Standards and
Technology (NIST)
allows engineers to tailor the electrical
resistance of individual layers in a device
without changing any other part of the
processing or design.
The tiny magnetic sensors in
modern disk drives are a sandwich of two
magnetic layers separated by a thin buffer
layer. The layer closest to the disk surface is
designed to switch its magnetic polarity quickly
in response to the direction of the magnetic
“bit” recorded on the disk under it. The sensor
works by measuring the electrical resistance
across the magnetic layers, which changes
depending on whether the two layers have
matching polarities.
As manufacturers strive to make
disk storage devices smaller and more densely
packed with data, the sensors need to shrink as
well, but current designs are starting to hit
the wall. To meet the size constraints,
prototype sensors measure sensor resistance
perpendicular to the thin layers, but depending
on the buffer material in the sensor, two
different types of sensors can be made. Giant
magneto-resistance (GMR) sensors use a
low-resistance metal buffer layer and are fast,
but plagued by very low, difficult to detect,
signals. On the other hand, magnetic tunnel
junction (MTJ) sensors use a relatively
high-resistance insulating buffer that delivers
a strong signal, but has a slower response time,
too slow to keep up with a very high-speed,
high-capacity drive.
What’s needed, says NIST
physicist Josh Pomeroy, is a compromise. “Our
approach is to combine these at the nanometer
scale. We start out with a magnetic tunnel
junction — an insulating buffer — and then, by
using highly charged ions, sort of blow out
little craters in the buffer layer so that when
we grow the rest of the sensor on top, these
craters will act like little GMR sensors, while
the rest will act like an MTJ sensor.” The
combined signal of the two effects, the
researchers argue, should be superior to either
alone.
DARPA Announces
Semi-Finalists For Urban Challenge
In August, the Defense Advanced
Research Agency (DARPA) announced 36
semi-finalists for its Urban Challenge, which is
the third in a series of competitions DARPA has
held to foster the development of autonomous
robotic ground vehicle technology. The DARPA
Urban Challenge features autonomous ground
vehicles conducting simulated military supply
missions in a mock urban area. One of the goals
of the challenge is to ensure safe operation in
traffic, which is essential to U.S. military
plans to use autonomous ground vehicles to
conduct important missions in urban
environments.
The semi-finalists will next
compete in the Urban Challenge National
Qualification Event (NQE) scheduled for October
26-31, 2007 in Victorville, California at the
site of the former George Air Force Base. The
top 20 teams from the NQE will move on to the
Urban Challenge final event on November 3, and
compete for cash prizes worth $2 million for
first, $1 million for second, and $500,000 for
third place. The events are open to the public
and can also be viewed by webcast.
For more information, see:
www.darpa.mil/grandchallenge/index.asp
"Tow Truck" Technology
Developed For Satellite Operations In Space
The Naval Research Laboratory's
Naval Center for Space Technology has achieved a
key milestone in development of autonomous
servicing of unaided spacecraft. Working with
the Defense Advanced Research Projects Agency (DARPA),
NRL has tested and ground-demonstrated guidance
and control algorithms for a robotic servicing
vehicle to autonomously rendezvous and dock with
customer satellites not pre-designed for
docking. As part of the Front-end Robotics
Enabling Near-term Demonstration (FREND) effort,
the DARPA/NRL team is advancing the
state-of-the-art in spacecraft autonomous
rendezvous and grappling, offering "tow-truck"
service to nearly every satellite currently, or
soon to be, in space. This service offers
potential for satellites to operate longer, to
be salvaged if they are in an inoperable orbit,
to be transferred to a new orbital position if
they are unable to make that transit on their
own, and has a capability for making certain
orbital regimes safer by transferring derelict
spacecraft or space debris into graveyard
orbits.
Full-scale laboratory
demonstrations have now been successfully
completed, proving that reliable autonomous
grapple of spacecraft hardware is feasible. The
NRL team has accomplished autonomous grapples
using a one-meter-long research grade robot arm,
custom developed flight traceable control
algorithms, research grade machine vision
cameras, prototype grappling mechanisms, and
flight traceable processors.
For more information, see:
www.nrl.navy.mil/pressRelease.php?Y=2007&R=47-07r
NASA And NIH Partner For
Space-Based Health Research
On Sept. 12, NASA and the
National Institutes of Health signed a
memorandum of understanding designed to help
American researchers use the International Space
Station to answer questions about human health
and diseases. The pact signals to researchers
the availability of a remarkable platform on
which to conduct experiments.
"The congressional designation
as a national laboratory underscores the
significance the American people place on the
scientific potential of the space station," NASA
Administrator Michael Griffin explained. "Not
only will the station help in our efforts to
explore the moon, Mars and beyond, its resources
also can be applied for a much broader purpose -
improving human health."
For more information, see:
www.nasa.gov/home/hqnews/2007/sep/HQ_07190_NASA_NIH_MOU.html
U.S. Regains Lead In Neutron
Science
The Spallation Neutron Source,
the Department of Energy's $1.4 billion research
facility at Oak Ridge National Laboratory, has
established a new record as the world's most
powerful accelerator based source of neutrons
for scientific research. The SNS surpassed the
previous record of 160 kilowatts for beam power,
held by the United Kingdom's ISIS facility,
while operating at 183 kilowatts. As the SNS
ramps up toward an eventual 1.4 megawatts of
power, the beams will produce up to 10 times
more neutrons than any existing pulsed neutron
source. The SNS's re-establishment of the United
States' leadership in neutron scattering means
that now many of the world's top researchers
will be coming to Tennessee to conduct
groundbreaking research.
For more information:
http://www.ornl.gov/info/press_releases/get_press_release.cfm?ReleaseNumber=mr20070830-00
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