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Listen Up, Bin Laden
Men claiming to be Osama bin Laden, the head of the al-Qaeda terrorist
network, and Saddam Hussein, the former leader of Iraq, have released
audio tapes exhorting their followers to battle on against the United
States. And every time one comes out, various experts weigh in on its
authenticity. But a researcher at the Oregon Health & Science University
(OHSU) says there are so many reliable voice transformation technologies
available that there is no way an expert can ever identify the voice
on an audio tape with 100 percent accuracy. Technically, there's
no way to be sure, says Jan van Santen, a mathematical psychologist
at the university's School of Science & Engineering.
Detecting a fake tape is almost impossibleespecially if the
audio quality is bad to begin with, which is often the case with these
tapes. The transformation method developed at OHSU requires an original
recording of the person who's to be imitated. Then someonea
mimic using the same dialect, rhythm and inflectionis recorded
reading the same text. After that, the mimic can say anything and the
software transforms the new speech into a recording that has the same
voice characteristics as the original. Van Santen says if a copycat
used the same technology devised at OHSU, his team could spot it because
they would know what cues to look for. But there are many
other transformation technologies that could be used to achieve the
same effect. Unless it was known which technology was used to fake
a tape, spotting the fraud is nearly impossible.
Van Santen reckons the chances of a phony Saddam tape surfacing are
greater than those of a fake bin Laden. That's because Iraq
is a more sophisticated country. And, don't forget, Saddam
has a history of employing doubles to represent him in public.
Flying Cleaner Skies
The use of hydrogen fuel cells in transportation usually refers to
the powering of automobiles. But a new 3- to 5-year student-driven
research program, sponsored by the nonprofit Foundation for Advancing
Science and Technology Education and Diamond Aircraft of Austria, at
the Florida Institute of Technology is developing a fuel-cell powered
electric airplane.
Fuel cells are considered a clean and renewable power source for the
future because they mix hydrogen with water to produce energy, and
their only emission is water. The students will reconfigure a Diamond
H-36 Dimona Motor-Glider, an aircraft now powered by a gasoline internal-combustion
engine. Bill Chepolis, an associate professor in Florida Tech's
School of Aeronautics, says the students will first design and analyze
various performance and propulsion options, and will also consider
human, safety, and environmental concerns. Finally, they will finish
and test a prototype.
Although fuel cells appear to have great potential, automotive engineers
are still grappling with some of the problems they present. Current
versions are big and heavy, for one thing, and very expensive. Those
issues also need to be addressed before they can be used on aircraft. The
problems are not insurmountable, but they have to be dealt with, Chepolis
says.
He thinks the auto industry will eventually lead the way to mass production,
which will quickly lower costs. Initially, he adds, it's likely
the first fuel-cell planes will be business jets. Fuel-cell commercial
aircraft are in the long-term future. Chepolis says that not only would
fuel-cell powered planes be nearly silent and clean but their widespread
use would also improve airports. For instance, noisy aircrafta
common cause for complaints from residents who live near airportswould
eventually disappear.
Phony Degrees Proliferate Down Under
AUSTRALIAEducation officials down under are worried that peddlers
of bogus college degrees are hurting their reputation overseas. Thousands
of students from Malaysia, Singapore, and increasingly China, flock
to Australian colleges and universities every year attracted by the
nation's reputation for high academic standards. But authorities
fear that the proliferation of phony degrees may cause future students
to decide to study elsewhere, which would be a big drain on the country's
economy. There are currently about 145,000 students in the system,
and foreign students are expected to pump almost $10 billion into the
economy by decade's end.
The states of New South Wales and Queensland, whose prestigious schools
attract many foreigners, are going after those hawking forged degrees
from reputable schools and real degrees from dubious institutions that
are in some cases no more than mail-drop addresses. Students
are provided with a degree using counterfeit university crests, serial
numbers, and student identification numbers, says New South Wales
State Education Minister Andrew Refshauge. He says fake degrees from
top universities can be easily obtained. Last year, New South Wales's
Department of Fair Trading investigated nearly two dozen allegations
about suppliers of worthless degrees. Queensland is in the process
of passing a law toughening controls on education providers. The state's
education minister, Anna Bligh, says that degree mill operators will
face heavy fines and possible jail time. In addition, any new universities
in the state will be monitored and their licenses reevaluated after
five years.
Shady operators target foreign students in all disciplines, including
engineering. The first priority for education officials is to guard
their reputations but they also want to prevent students from purchasing
worthless degrees. They want a degree from an Australian university
to be worth far more than the paper it's printed on.
A COMPETITION WITH CONCRETE RESULTS
Concrete canoe. Sounds like a 60s heavy-metal band (think Led
Zeppelin and Iron Butterfly). A concrete canoe is not a guitar-wielding
outfit but an actual watercraft. And not only do concrete canoes float,
they are as sleek and lightweight as the fiberglass and aluminum variety.
Every year since 1988, there is a National Concrete Canoe Competition,
pitting university teams from across the country against one another
in a contest that includes racing. It's jointly sponsored by the
American Society of Civil Engineers and Master Builders Inc., a company
that produces concrete admixtures. At this year's three-day event,
held in Philadelphia in June and hosted by Drexel University, the University
of Wisconsin's 145-pound, 22-foot canoe called the Chequamegon
(pronounced shwa-me-gun) took top honors and $5,000 in scholarship
money. Second place went to the Phoenix, a 160-pound canoe built by
students from Canada's Universite Laval. The University of California-Berkeley's
Bearkelium, weighing in at 160 pounds, came in third. Berkeley's
team used a new construction technique called sheetcrete: Concrete
is rolled into 1/8-inch sheets and then transferred to the form; vibration
is used to join the sheets.
Twenty-five schools competed in the national competition this year.
The canoeswhich must be 90 percent concretesometimes weigh
as little as 70 pounds and are designed on computers by civil engineering
students. To make the flexible, thin canoe concrete, all sorts of admixtures
are added to the portland cement mix: rice, tiny glass orbs, perlite,
silica fume.
Teams' final scores have four components: Slalom/endurance and
sprint races account for 30 percent; a design paper 30 percent; a business
presentation 25 percent; and a final racing canoe, which must pass
a floatation test, 15 percent.
Missing from this year's lineup was the historically dominating
University of Alabama-Huntsville. The school has won five championships,
more than any other school. This year, however, Bama was bammed
in a regional competition. Alabama's John Gilbert, 55, a professor
of mechanical and civil engineering, is an expert in concrete canoeing.
He even runs a Web site on the topic: concretecanoe.org. He praised
Wisconsin's victory, calling it and the canoe impressive. But,
he adds, behind the fun and games is some serious engineering. For
the students, Gilbert says, it's a great exercise in teamwork
and thinking outside the box. And the innovations they come up with,
he adds, are useful for the industry. Mike Shydlowski, Master Builders
president and CEO, says the students and the boats demonstrate that
concrete is a remarkable and versatile building material. Indeed,
Gilbert envisions concrete being used for such things as rocket casings
and aircraft wing flaps. Hmm, a concrete rocket. Great name for a rock
band.
EARLY DETECTION FOR LUNG CANCER
GLASGOWOne of the diabolical aspects of lung cancer is that
it often spreads to fatal levels before symptoms appear, and early
detection remains difficult. But thanks to technology devised to improve
prospecting for gas and oil reserves, doctors may soon be able to discover
the onset of lung cancer at a much earlier stage.
Researchers at the Optics Group at Glasgow University in Scotland
have devised a unique sensor system that can sniff out ethane at levels
less than one part per billion. Trace amounts of hydrocarbons, including
ethane, naturally leak from oil and gas reserves. Physics professor
Miles Padgett and his team worked on a system to monitor minute amounts
of ethane; software they developed combines the ethane measurements
with wind direction to pinpoint the source of the leak. The system
uses an infrared laser to measure the gas. It can detect ethane by
measuring the amount of infrared light absorbed at a specific wavelength.
So how does that lead to the detection of lung cancer? Humans react
to cancer cells by producing higher levels of free radicals, chemicals
that reduce cell membranes to hydrocarbons, including ethane. Physicians,
including Dundee University's Chris Longbottom, who were visiting
the Glasgow laboratory, immediately saw the potential of using the
geologists' tool to screen for cancer. Connected to a breathalyzer,
the ethane detection system appears to accurately diagnose lung cancer
by sensing trace amounts of ethane. In clinical trials at Dundee's
Ninewell Hospital, the breath of 50 patients was analyzed. Of 21 suffering
from lung cancer, only one failed to produce a high ethane reading.
But there was a problem with false negatives. Five patients who were
cancer free also had measurable ethane readings. Padgett has begun
a two-year project to improve the device.
WARBLING OUT A WARNING
Once upon a time, miners used canaries to determine if the air in
mines was riddled with odorless, colorless, and tasteless poisonous
gasses. If the canary died, it was time to run for the exit. Now researchers
at the University of CaliforniaBerkeley have devised a canary
on a chip, a micro-electromechanical device that could act as
a warning system for biochemical attacks. The technology is a continuation
of bionic chip research conducted by Boris Rubinsky, a professor of
mechanical engineering and bioengineering, and a former grad student
Yong Huang, who has a doctorate in mechanical engineering. Three years
ago, they created a chip that linked a living biological cell with
electronic circuitry. Now, they've determined, such a cell chip
could act as a sensor. Rubinsky and Huang discovered that when a cell
is exposed to a toxic agent, there is within milliseconds a spike of
electrical resistance in its membrane as it dies. The chip monitors
and records that electrical signature in real time. The chips are nonspecific,
in that they will record a cell's fatal reaction to any toxin.
Using wireless technology, the chip could set off an alarm. The chips
could be embedded into vulnerable areas, like subway stations. Or placed
on badges worn by soldiers. Huang says two problems remain to be solved:
How to extend the life of the cells beyond 30 days and how to store
the chips. Nevertheless, he adds, with proper funding the canary chip
technology could be commercialized within two years.
FILL ER UP WITH AIR , PLEASE
Now here's a concept for making the air that we breathe cleaner:
Cars that are partly fuelled by air. Tsu-chin Tsao, a researcher at
the University of California-Los Angeles (UCLA), working with engineers
at the Ford Motor Co., has devised a plan for a hybrid car that uses
airnot electricityto boost fuel efficiency.
When cars slow down, their kinetic energy is transformed to heat by
the friction brakes. Hybrid cars capture braking energy, convert it
to electricity, store it in batteries and use the power to run a small
electric motor that helps the car accelerate. That reduces the use
of gasoline, a fossil fuel that when burned emits pollutants, primarily
carbon dioxide. While the technology can cut emissions to impressively
low levels, adding a second battery and motor is costly. They're
also heavy, which forces automakers to reduce vehicle weight in other
areas. Not surprisingly, the resulting hybrid cars are expensive, and
that has slowed their acceptance in the marketplace. But Tsu-chin Tsao's
air hybrid converts the braking energy to air, which is compressed
and stored. When that air is allowed to expand, there is a burst of
power that can help accelerate a car. And air hybrids need only a small
tankweighing about 66 poundsto hold the compressed air.
So his proposed technology is cheap as well as lightweight. It's
also efficient: Computer modeling of a 2.5 liter, V-6 engine using
the system indicated that it would improve fuel efficiency in urban
areas by 65 percent and on the highway by 12 percent.
Tsao, a professor of mechanical and aerospace engineering at UCLA's
Henry Samueli School of Engineering and Applied Science, says the key
to air hybrids is a camless valve train. An engine's valve system
lets in air and fuel, and releases exhaust. Tsao's system uses
the engine to compress the air when it is not combusting fuel. That
requires a valve timing system that can react almost instantaneously.
That's accomplished by using actuators controlled by microchips.
One minor hurdle that Tsao thinks can easily be surmounted is that
air cools when it expands, and for propulsion purposes, it's best
to have warm air. Tsao would like to build a prototype air hybrid car,
but right now there are no funds available to do so. The concept
looks feasible, he says. But without funding, it's a concept
that's still floating in the air.
ON THE MARK
Biomechanical chips that rely on harmless bacteria could be used to
build minuscule machines that deliver drugs to patients with pinpoint
accuracy, say two University of Arkansas researchers. Mechanical engineer
Steve Tung and bioengineer Jin-Woo Kim have developed a micro-pump
that uses spinning bacteria to move minute amounts of liquid. The bacteria
attach themselves to a flat surface and spin at a rate of 10 cycles
per second. By fluctuating the bacteria's intake of a nutrient,
the researchers can make the cells stop and go and change speeds. A
series of the cells attached to a glass-walled chamber can pump 0.25
nanoliters of liquid a minute, according to their computer model. Tung
says that preliminary measurements of flow velocity around the spinning
cellstracked by the insertion of a polymer bead into the flowindicate
that the model is correct. Now Tung and Kim are working on a polymer
material system that will release the nutrient in a controlled fashion.
One drawback: After 24 hours, the bacteria die. But, he adds, We
believe this can be improved once we develop the nutrient delivery
system. However, this is not going to be a walk in the park, since
we have to find out what is just the right amount of nutrient for maintaining
cell spinning. Tests using various chemicals, Tung adds, have
been very encouraging. A potential plus to the bacteria pump:
It should be low cost. The cells can be grown easily and cheaply. After
all, tiny pumps shouldn't come with big price tags.
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