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Sunday, November 4, 2012
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Wednesday, September 12, 2012
Impatient Futurist Science Finds a Better Way to Teach Science
Impatient Futurist Science Finds a Better Way to Teach Science
After doing some much-needed research, cognitive scienctists are suggesting a new way to boost students’ lagging scores: Get rid of the hallowed (and stultifying) classroom lecture.
Clearly the problem is not the content or presentation style of my lecturing, which, as I may have neglected to mention, is brilliant, or so I was once assured by a student who stayed after class to ask for a sixth extension on an assignment. Then again, from what I recall of my college days, I wasn’t exactly on the edge of my seat at my professors’ lectures, either. And most of my fellow lecturers don’t report much different. Could the problem be with the nature of lecturing itself?
To find some answers, I posed this question directly to Carl Wieman, associate director for science at the Office of Science and Technology Policy at the White House. Wieman, to be blunt, knows zero. In fact, he won a Nobel Prize for his extraordinarily low achievement. During the mid-1990s in a University of Colorado physics lab, Wieman enlisted lasers to bring matter as close to absolute zero as anyone is likely to get—a temperature so low that atoms freeze together into quantum-mechanical clouds predicted by Einstein but never before observed. “That was challenging,” Wieman says. “But changing how people teach, that’s really hard.”
Wieman should know. Aside from having captained his share of undergraduate physics-for-poets courses, Wieman is now, in a sense, America’s First Science Teacher, in that President Obama took him on last year with the assignment of improving science education in America.
It’s no secret we’ve got some work to do along those lines. A widely accepted standardized test administered in 2009 to large samplings of high school students in industrialized countries found that U.S. students scored 23rd in science, with students from China scoring highest. The United States has long closed the knowledge gap in graduate school, where our programs still lead the world in the production of new scientific insights, as measured by publications in science journals. But a study by the Royal Society in the U.K. earlier this year reported that even in this regard China is on track to pull ahead of the United States as early as 2013.
Noting that his physics Ph.D. students were arriving from college woefully unprepared but went on to thrive in the lab-oriented atmosphere of grad school, Wieman suspected the problem might have its roots in that core teaching tool of the college experience, the undergraduate lecture. He unearthed some research to back up that hunch.
A University of Maryland study of undergraduates found that after a physics lecture by a well-regarded professor, almost no students could provide a specific answer to the question, “What was the lecture you just heard about?” A Kansas State University study found that after watching a video of a highly rated physics lecture, most students still incorrectly answered questions on the material. Wieman himself found that when he quizzed students about a fact he had presented 15 minutes earlier in a lecture, only 10 percent showed any sign of remembering it.
Investigating further, Wieman learned what cognitive scientists have proven repeatedly in recent years: Humans don’t learn concepts very well by having someone blab on about them. In other words, the college lecture is to a large extent a waste of time.
Graham Gibbs, former director of the Oxford Learning Center, which helps instructors improve their teaching skills, has been making that argument for three decades. In a landmark paper, “Twenty Terrible Reasons for Lecturing,” he points to “overwhelming” evidence that lectures are an ineffective way for universities to achieve the educational objectives they set. Academia continues to rely heavily on lectures, Gibbs argues, because professors are “overworked,” “ignorant,” and “don’t know how to design courses.”
The simple insight that lectures don’t work well raises two questions. First, where do I apply to get those 3,000 hours of my life back? And second, what does work? To demonstrate, Wieman and colleague Katherine Perkins put together a science-learning initiative at the University of Colorado. The next year he and his wife, Sarah Gilbert, then a physicist at the National Institute of Standards and Technology, created a second one at the University of British Columbia after the institution pledged $12 million over six years to the program.
In these test settings, various science curricula were revamped to get them to jibe with the latest cognitive science research on effective learning, which points to more interactive approaches that include immediately and repeatedly putting new information to use. Students in science courses were continually peppered with questions that they all had to answer via wireless handheld clickers. The students were frequently broken into small work groups to try their hands at solving problems using the material they had just learned, and they took at least two midterms each class.
The results have been eye opening. In a study published in the journal Science, one section of a University of British Columbia physics course about electromagnetic waves was taught by the cognitive approach, while another section was taught by the standard course lecture. The first group scored an average of 74 percent when tested on the material, while the second group scored only 41 percent. “We’ve been able to clearly demonstrate how much better we can do in teaching students,” Gilbert says.
But scientists who teach have proven reluctant to toss out the lecture, never mind the evidence that it doesn’t work. “They say this is the way it’s always been done, and it was good enough for them, so it’s good enough for their students,” Wieman says. Were this attitude to hold in medicine we would still be bloodletting, in physics we would be trying to reach the moon with very large rubber bands, and in economics we would still be suffering major worldwide financial crashes. (Well, physics and medicine are advancing, anyway.) Wieman is using his White House position to push universities to reward professors for the quality of their teaching, not just their research results.
At the University of Cambridge, cognitive researcher Michelle Ellefson is making her own bid to improve teaching by applying lessons from cognitive science. “Decades ago, we thought children’s brains functioned much like those of brain-damaged adults,” she says. In particular, younger brains seemed short on prefrontal cortex, the seat of so-called executive functions that, among other things, enable us to switch our attention from what we are learning now to something we learned earlier. That’s a problem in the classroom, where teachers tend to focus on one subject for several classes and then move on to another one, often causing students to lose touch with whatever knowledge they had just acquired.
But more recent research suggests that children who are struggling can readily improve their executive functions with appropriate stimulation. In other words, recalling old lessons is just a matter of training. Ellefson ran a study in which a group of students were briefly pushed every day to revisit earlier material, while another group just plowed ahead with the new material. “After eight weeks, the group that did daily reviews became just as good at switching back and forth between new and old material as adults are,” she says, adding that test scores jumped accordingly. “It’s a simple classroom change that can make a big difference.”
Such results come as no surprise to Kurt Fischer, who directs the Mind, Brain, and Education Program at Harvard University. The reason scientists are likely to turn up all sorts of simple new ways of dramatically improving classroom learning, he claims, is that until recently they haven’t bothered to look for them. “We have massive research programs in agriculture, meteorology—even the cosmetics industry is constantly researching,” he says. “But there hasn’t been much research in education. Now we’re starting to discover what techniques actually work.”
Which leaves me with a few new tricks to try out in my college class this semester. Hey, maybe the next time a light goes on in the eye of one of my students it won’t be merely the reflected glare of a text message.
Impatient Futurist High-Tech Soaps Just Might Clean Up the Planet
Impatient Futurist High-Tech Soaps Just Might Clean Up the Planet
The worst industrial spills call for something stronger than the old-fashioned bar sitting in your soap dish.
New-age soaps can respond to light, acidity, temperature,
pressure, or magnetism—so they clean
up just the right nasty atoms.
David Plunkert
Between freak Arctic melting, Japanese nuclear melting, and antibiotic resistance
popping up everywhere, I can’t help but see the world as tiptoeing into
pre-apocalypse. If there is some sort of crapstorm coming and I’m lucky
enough to survive it, there’s one thing I know for sure: I’m going to
need a really good hand-cleaner for the aftermath. When I come in from a
hard day of zombie hunting, it won’t be just dirt that I’ll need to get
out from under my fingernails.pressure, or magnetism—so they clean
up just the right nasty atoms.
David Plunkert
Actually, I could use that doomsday soap now—or rather, we all could. That’s because most of the human race has no intention of patiently waiting for an unspecified apocalypse and has already gotten a head start on mass despoiling. So far the tides of toxic waste and exploded-oil-rig crude haven’t made it as far as my sleepy burb. But right now somebody somewhere is facing a mess that Softsoap won’t make a dent in.
Hold that last thought—soap is, in fact, exactly what some of the world’s smartest cleanup experts are now touting for the next big spill. You might suppose that scrubbing bubbles would be a poor choice of weapon against giant blobs of crude, especially compared with giant oil-corralling booms and high-tech oil-skimming robots. But soap has some important advantages: It really cleans things up (that’s what it is made to do, after all), and at the end, all that oily soap can be neatly and completely gathered up with a magnet.
You didn’t know soap was magnetic? You’re obviously using one of those old-fashioned iron-free soaps. The new stuff can be found in the laboratory of research chemist Julian Eastoe at the University of Bristol in the U.K. Sure, any numbskull can pour a bag of iron filings into a jug of Tide (trust me, my wife is still screaming). The trick is to get the iron to chemically bond to the soap—or as chemists like to say, the “surfactant”—and in sufficient quantity to enable the ironic solution to be pulled by a magnet.
A Magnetic Mop for Oil
Eastoe played around with a number of surfactants and iron compounds before hitting on solutions of iron salts, related to the surfactants in mouthwash and fabric softeners but with some magnet-friendly metal thrown in. In theory, this soapy slop could be heaved by the tankful onto oily shorelines to mix with the spilled crude, and then sucked up by magnet-equipped vehicles or volunteers, leaving behind none of the toxic solvents or messy detergents commonly employed in cleaning oil. “It would be especially useful for cleaning contaminated seabirds,” notes Eastoe, who has obviously never had to wield a magnet against an infuriated, oil-and-soap-covered seagull.
Pennsylvania State University materials science professor T. C. Chung has come up with a different take on an oil-spill cleaner. Chung was working for Exxon in 1989 when that company’s notorious Valdez tanker spilled 11 million barrels of crude into Alaskan waters. When BP’s Deepwater Horizon disaster blackened much of the Gulf of Mexico in 2010, Professor Chung was determined to become Professor Clean. “I saw that in all that time, we still hadn’t come up with a better way to clean up oil than a paper towel,” he says. “I knew there had to be a solution.” That solution, he decided, was Petrogel.
Chung worked with a cheap, plasticlike compound called a polyolefin, a long-chain molecule. Though the stuff isn’t technically a surfactant, he chemically tacked on branches to the molecular chain and got it to form a molecular web that surrounds particles of oil. The result: One pound of Petrogel will combine with more than 40 pounds of oil, preventing it from dispersing into the ocean or from sticking to sand or dolphins. “You could spray it on a spill as powder, trap all the oil as gel, and then recover it with skimmers,” he says. And since a polyolefin is made up of hydrocarbons, like oil, the easy-to-handle gel could be refined as if it were plain old oil. It wouldn’t have to be dumped somewhere, and some of the costs of recovery could be, well, recovered.
The fact that chemically hot-rodded Jell-O and fabric softener turn out to be mighty weapons in the fight against catastrophic soilage might tempt you to rummage through your household items for other potential tools. You need go no further than your pocket or purse, due to the work of a Michigan Technological University chemical engineer who has figured out how to turn chewing gum into another super-spill tamer. Gerard Caneba zeroed in on polyvinyl acetate, a major ingredient of gum. He discovered that this natural, biodegradable stuff needs only a bit of strategic molecular tweaking to become a surfactant that readily foams up in contact with water. “Everyone knows chewing gum is good for making bubbles,” he says. “It’s already pretty close to being a detergent.” Oh Bazooka Joe, is there anything you can’t do?
The trick to making this gummy soap into an oil-fighter, Caneba found, was to manipulate the compound so that one part of the molecule latches onto water while another part cozies up to crude. The result is a liquid that, when squirted at the edges of a spill, forms a foamy barrier around it that will push the spill in the direction in which the liquid is applied. “If you try squirting water or other liquids at oil, they’ll just move around or through it,” Caneba says. “This foam will stay up against the oil and herd it.” It can even be sprayed upwards via an underwater pipe at the bottom of an underwater plume of spilled oil in order to bring it to the surface. The herding action can keep the oil from dispersing in the water and from reaching shorelines.
If you’re still not impressed with the mega-filth-fighting capabilities of this soapy gum, consider that it also works wonders against “red mud,” a highly caustic sludge left over from aluminum manufacturing; a recent red-mud spill in Hungary forced hundreds of villagers to evacuate. When Caneba’s stuff is sprayed on it, a series of chemical reactions converts the mud into a nontoxic, foamy goo that can be compressed into a durable building material. “It would be great for patio tiles and ceiling insulation,” Caneba suggests. I, for one, am completely behind the idea of cleaning the planet while redecorating.
Detox Gels and Foaming Meds
If oily Jell-O cannot mop up your toxic spill, maybe congealed soybean oil can. Building on research conducted at the Savannah River National Laboratory, a company called EOS Remediation in Raleigh, North Carolina, has found a secret ingredient that turns soybean oil into a gel. But here’s the interesting part: If you stir it up a bit, it temporarily becomes a liquid that can be pumped into soil that’s been contaminated with toxins. Once the liquid is in the soil, it reverts to gel form and stays that way for a long time—years, even. Taking advantage of that long lifetime, EOS laces its gel with toxin-eating bacteria, including one that can break down the chlorinated solvents commonly used to degrease machine parts. The idea is that the bacteria will remain in position for however long it takes to leave the soil squeaky clean—not counting the gel, which is basically edible at the end. It worked for cleaning up a wastewater site at Savannah River, though nobody actually showed up to dine on the end product.
Frankly, I’m doing a huge disservice to soap science by implying that all it can do is save the planet from toxic catastrophes. Eastoe, for example, envisions all kinds of surfactant-based miracles. “The chemical imagination runs wild with the possibilities,” he says. True, coming from a soap scientist, you might wonder if “wild” needs to be taken with a grain of sodium chloride. But Eastoe and other chemists are creating genuine supersoaps by finding ways to get surfactant molecules to lose their foamy properties [pdf] under particular conditions so that the foam can, in effect, be turned off and on at will.
Eastoe has created foams that can be switched on and off with light [pdf], so that if mixed with insecticides or herbicides and sprayed on plants, they could foam up only at night or only during the day, whenever they were most effective. He is considering drug-laced foam that could be swallowed by a patient and then de-foamed with an electric field so that it would drop its drug payload only when it’s at the right place in the body. And he points out that foam doesn’t just clean oil up; it can also produce it cleanly by helping to drag raw crude out of deep deposits.
So inspiring to me is this work that I’ve started experimenting with other household items to see if I can invent my own supersoap. I’ve already substantially contributed to the field by brilliantly ruling out organic ketchup and lite chocolate syrup as candidates. Though I have to admit, it’s hard to focus with all that screaming in the background.
The Velociraptor-Like Robot That Could Save Your Life
The Velociraptor-Like Robot That Could Save Your LifeA balancing trick used by geckos, and possibly dinosaurs, is helping to make more agile and helpful rescue robots.
On your mark, get set, go! Tailbot may not have the speed of an agama
lizard (left) or an extinct velociraptor (right), but it is just as adept at
maneuvering its tail in midair to set up a perfect landing.
Dr Torsten Wittmann/Science Photo Library
Biologist Robert Full’s
lab is brimming with critters in motion: scuttling crabs, crawling
centipedes, prowling geckos. These animals serve as inspiration as he
and his colleagues at the University of California, Berkeley, build
robots that are fast, steady, and agile. In January, Full used his
analysis of leaping lizards to design a rugged bot that can navigate
through the rubble following an earthquake or other disaster.lizard (left) or an extinct velociraptor (right), but it is just as adept at
maneuvering its tail in midair to set up a perfect landing.
Dr Torsten Wittmann/Science Photo Library
Full’s breakthrough came from observing African agama lizards, which have a remarkable ability to stick a perfect landing after vaulting through the air. The lizards keep their balance during flight, Full found, by moving their tails up and down to counteract the motion of their bodies and keep themselves stable. He thought about how he could apply that technique to search-and-rescue robots, which must remain upright as they clamber across precarious terrain.
Within a few months, Full and his team had built a four-wheeled, foot-long vehicle with a stiff tail section, which they dubbed Tailbot. When it was driven off a ramp without any postlaunch adjustments, Tailbot nosedived into the ground. But when the robot lifted its tail after it left the ramp—just enough to make up for the vehicle’s forward pitch—it landed even more gracefully than the lizards. Full and his team are now working on a robot that can stabilize itself if it starts to bank left or right in the air.
Full’s lizard analysis also led him into unfamiliar territory: paleontology. He found 40-year-old scientific papers suggesting that the velociraptor—a swift predatory dinosaur—used a similar body-stabilizing trick. Full made a mathematical model of how the creature moved, based on its bone structure, and discovered that the raptors were probably as good as or better than present-day lizards at staying upright by using their tails. Although Full can never confirm his theory, he is able to assess the motion of the computer-generated raptors in the film Jurassic Park. “If you watch that scene where the velociraptor is jumping from the balcony,” he says, “it moves its tail perfectly.”
How to Make Anything Disappear
Sophisticated cloaking devices
may soon hide objects from light,
sound, water, even earthquakes.
Back in 2006 Harry Potter was all the rage in the engineering world. That year a team at Duke University built the first rudimentary device for hiding objects, akin to the boy wizard’s invisibility cloak. But in technology as in the movies, Harry Potter is now old news. Over the past six years, scientists have moved beyond mere invisibility: If they could build cloaks for light waves, then why not design materials to conceal sound and even ocean waves?
A whole suite of invisibility cloaks are now under development, all building on the same basic principle as the first prototype. When we perceive an object, we are actually detecting the disturbances it creates as energy waves bounce off it. The Duke cloak, constructed from a synthetic structure called a metamaterial, prevented those disturbances by bending light waves around the object, allowing them to continue flowing like water in a stream around a rock (concept shown at right). Sure enough, that technology is not limited to light. In the latest designs it is being applied to mask all kinds of other waves, with the potential for zeroing out sound pollution and protecting cities from earthquakes. Meanwhile, scientists continue to pursue the original invisibility concept—work that is sparking a lot of interest in military surveillance circles.
1 VISIBLE-LIGHT CLOAK
The Tech: A group of physicists led by Tolga Ergin and Joachim Fischer at the Karlsruhe Institute of Technology in Germany built a light-bending fabric last year that—for the first time—rendered a cloaked object invisible to the human eye from any viewing angle.
What It's Made of: A rigid synthetic polymer composed of tiny rods spaced about 350 nanometers (billionths of a meter) apart, a gap small enough to manipulate waves of visible light.
How it Works: As a test, researchers laid the cloak over a flat surface with a small bump in the middle. The cloak bent incoming light rays around the bump and bounced them back as if they had struck a flat surface. Observers would never know the bump existed.
Applications: For now, this cloak can hide only small imperfections on flat surfaces. But eventually, scientists hope to scale it up to conceal much larger objects anywhere in space. The U.S. Defense Advanced Research Projects Agency (Darpa) started investing in metamaterials way back in 2001, and while it doesn’t like to reveal specific intentions, the agency would certainly be interested in cloaks that conceal soldiers and military equipment.
2 SOUND CLOAK
The Tech: Last year a Duke University team led by engineer Steven Cummer built a cloak that rendered an object “invisible” to sound waves.
What It's Made of: Stacked sheets of one-millimeter-thick perforated plastic (the actual engineering of these cloaks is difficult but unglamorous). The sheets’ holes and arrangement allow the cloak to manipulate sound waves.
How It Works: It hides an object much like Ergin’s light cloak does. Cummer placed the perforated sheets over a 10-centimeter-long block of wood. The cloak bent sound waves heading toward the block so that they avoided the cloaked area and rebounded as if it were not there. If the block had ears, it would not have heard any sound from outside the cloak.
Applications: Sonic cloaks could steer sound waves around beams and columns in a concert hall to give every seat perfect acoustics, or block the noise pollution from that chatty coworker in a neighboring cubicle. Such cloaks could also conceal submarines from the pulses of enemy sonar, although Cummer considers that a major challenge—he cannot just slap thick layers of plastic onto a military sub 3 EARTHQUAKE CLOAK
The Tech: Last February Sang-Hoon Kim at the Mokpo National Maritime University in South Korea and Mukunda Das at Australian National University presented a blueprint for seismic cloaks that could protect buildings from earthquakes.
What It's Made of: An array of giant concrete cylinders, 60 to 200 feet in diameter, each drilled with small holes to manipulate seismic waves. The cylinders would be installed underground, arranged to encircle a building’s foundation.
How It Works: Seismic waves propagate through the Earth much as sound waves move through air, so the concept is similar to the sound cloak. The difference is that engineers do not want merely to steer seismic waves around buildings, because doing so would end up inflicting damage on other structures. That’s where the thick concrete comes in: As the cylinders deflect the seismic waves, they would also absorb some of the waves’ energy and convert it into heat and sound. The cloaked building would vibrate barely at all, while the structures around it would experience a weakened temblor.
Applications: The goal is protecting nuclear reactors, dams, airports, government offices, and other sensitive and essential structures from earthquake damage. Kim expects to consult with engineers building small-scale test models soon.
4 WATER CLOAK
The Tech: Last year, Duke engineers Yaroslav Urzhumov and David Smith proposed a means of cloaking ships as they move through the water.
What It's Made of: A network of small water-deflecting blades and pumps encasing the bottom of the ship.
How It Works: As a ship chugs ahead, it drags water along with it and leaves a wake behind. Urzhumov’s contraption would scoop up water in front of the bow, steer it around the ship, and release it behind the stern. Water behind the ship would move at the same speed and in the same direction as at the front of the ship. The result: The ship would glide through the water without disturbing it.
Applications: Urzhumov says ships will not be getting fitted for cloaks for at least a decade, but the benefits are worth the wait. Cloaked ships could move faster, since they would encounter little friction from the surrounding water. They would also be harder to spot without a trail behind them. If that sounds like something that would make naval officers salivate, it is: The Navy helped fund the Duke study.
Back in 2006 Harry Potter was all the rage in the engineering world. That year a team at Duke University built the first rudimentary device for hiding objects, akin to the boy wizard’s invisibility cloak. But in technology as in the movies, Harry Potter is now old news. Over the past six years, scientists have moved beyond mere invisibility: If they could build cloaks for light waves, then why not design materials to conceal sound and even ocean waves?
A whole suite of invisibility cloaks are now under development, all building on the same basic principle as the first prototype. When we perceive an object, we are actually detecting the disturbances it creates as energy waves bounce off it. The Duke cloak, constructed from a synthetic structure called a metamaterial, prevented those disturbances by bending light waves around the object, allowing them to continue flowing like water in a stream around a rock (concept shown at right). Sure enough, that technology is not limited to light. In the latest designs it is being applied to mask all kinds of other waves, with the potential for zeroing out sound pollution and protecting cities from earthquakes. Meanwhile, scientists continue to pursue the original invisibility concept—work that is sparking a lot of interest in military surveillance circles.
1 VISIBLE-LIGHT CLOAK
The Tech: A group of physicists led by Tolga Ergin and Joachim Fischer at the Karlsruhe Institute of Technology in Germany built a light-bending fabric last year that—for the first time—rendered a cloaked object invisible to the human eye from any viewing angle.
What It's Made of: A rigid synthetic polymer composed of tiny rods spaced about 350 nanometers (billionths of a meter) apart, a gap small enough to manipulate waves of visible light.
How it Works: As a test, researchers laid the cloak over a flat surface with a small bump in the middle. The cloak bent incoming light rays around the bump and bounced them back as if they had struck a flat surface. Observers would never know the bump existed.
Applications: For now, this cloak can hide only small imperfections on flat surfaces. But eventually, scientists hope to scale it up to conceal much larger objects anywhere in space. The U.S. Defense Advanced Research Projects Agency (Darpa) started investing in metamaterials way back in 2001, and while it doesn’t like to reveal specific intentions, the agency would certainly be interested in cloaks that conceal soldiers and military equipment.
2 SOUND CLOAK
The Tech: Last year a Duke University team led by engineer Steven Cummer built a cloak that rendered an object “invisible” to sound waves.
What It's Made of: Stacked sheets of one-millimeter-thick perforated plastic (the actual engineering of these cloaks is difficult but unglamorous). The sheets’ holes and arrangement allow the cloak to manipulate sound waves.
How It Works: It hides an object much like Ergin’s light cloak does. Cummer placed the perforated sheets over a 10-centimeter-long block of wood. The cloak bent sound waves heading toward the block so that they avoided the cloaked area and rebounded as if it were not there. If the block had ears, it would not have heard any sound from outside the cloak.
Applications: Sonic cloaks could steer sound waves around beams and columns in a concert hall to give every seat perfect acoustics, or block the noise pollution from that chatty coworker in a neighboring cubicle. Such cloaks could also conceal submarines from the pulses of enemy sonar, although Cummer considers that a major challenge—he cannot just slap thick layers of plastic onto a military sub 3 EARTHQUAKE CLOAK
The Tech: Last February Sang-Hoon Kim at the Mokpo National Maritime University in South Korea and Mukunda Das at Australian National University presented a blueprint for seismic cloaks that could protect buildings from earthquakes.
What It's Made of: An array of giant concrete cylinders, 60 to 200 feet in diameter, each drilled with small holes to manipulate seismic waves. The cylinders would be installed underground, arranged to encircle a building’s foundation.
How It Works: Seismic waves propagate through the Earth much as sound waves move through air, so the concept is similar to the sound cloak. The difference is that engineers do not want merely to steer seismic waves around buildings, because doing so would end up inflicting damage on other structures. That’s where the thick concrete comes in: As the cylinders deflect the seismic waves, they would also absorb some of the waves’ energy and convert it into heat and sound. The cloaked building would vibrate barely at all, while the structures around it would experience a weakened temblor.
Applications: The goal is protecting nuclear reactors, dams, airports, government offices, and other sensitive and essential structures from earthquake damage. Kim expects to consult with engineers building small-scale test models soon.
4 WATER CLOAK
The Tech: Last year, Duke engineers Yaroslav Urzhumov and David Smith proposed a means of cloaking ships as they move through the water.
What It's Made of: A network of small water-deflecting blades and pumps encasing the bottom of the ship.
How It Works: As a ship chugs ahead, it drags water along with it and leaves a wake behind. Urzhumov’s contraption would scoop up water in front of the bow, steer it around the ship, and release it behind the stern. Water behind the ship would move at the same speed and in the same direction as at the front of the ship. The result: The ship would glide through the water without disturbing it.
Applications: Urzhumov says ships will not be getting fitted for cloaks for at least a decade, but the benefits are worth the wait. Cloaked ships could move faster, since they would encounter little friction from the surrounding water. They would also be harder to spot without a trail behind them. If that sounds like something that would make naval officers salivate, it is: The Navy helped fund the Duke study.
Tuesday, September 11, 2012
An Article That Made Me Sad, and a Little Response to Readers
An Article That Made Me Sad, and a Little Response to Readers
Bill Galston is one of the great intellects around, and this week he wrote an especially bracing short piece at TNR after he read a quote from Mitch Daniels that obviously put a bee in Bill's bonnet.
The
quote from Daniels was this: “He [Obama] does not understand where
wealth and jobs come from. It comes from a successful private sector or
not at all … Government does not create wealth or income. It just
shuffles it around and charges a price, a cost for that service or
disservice.”
Galston unloads and is worth quoting at some length:
Daniels
is obviously right that a vigorous private sector is and must be the
principal locus of wealth and employment. But he is dead wrong to
suggest that government is simply redistributive or worse, a dead-weight
drag on the economy. Throughout American history, government has made
investments that have fueled economic growth. Is it really necessary to
remind the governor of facts that young people used to learn in high
school? Is he not familiar with the historic role of the public sector
in catalyzing the construction of canals, railroads, bridges, and
roads—indeed, every aspect of the infrastructure that ensures the
mobility of raw materials and finished goods? What about human
capital—public schools, land-grant colleges, student grants, and loans?
Surely the governor understands that individuals’ ability to earn a
decent living, and America’s ability to compete in the global economy,
depends more and more on the education and training of our workforce.
And what about basic research, which helps replenish the well of ideas
from which so many commercially viable products and processes are drawn?
The
concept of “public goods” is hardly the creation of liberal ideologues.
Standard economics tells us that market mechanisms tend to undersupply
investments that benefit those other than the investors. Although we
would all be better off with a better-trained workforce, each business
has reason to believe that others could end up enjoying the fruits of
its own training expenditures. The aggregate of individual decisions,
each of which is rational, yields an inadequately trained workforce.
When government acts to fill the gap, it is neither redistributing
income nor charging for a service. It is playing its appropriate role in
helping to create income, wealth, and jobs.
I
like that second graf especially, because it is an entirely
market-based, unsentimental case for government. Markets send benefits
to investors. Since many citizens are not investors, a mechanism is
needed to send benefits their way.
This
is an argument that applies very specifically, by the way, to health
care. We don't have much in the way of preventive medicine in the US, at
least compared to Europe and Canada. And the reason we don't is
expressed in Galston's second paragraph. It's because health care is
largely provided by employers. To paraphrase Galston somewhat, while it
is in society's interest to have more preventive medicine, it isn't in
any single employer's interest to provide it, because that business has
good reason to think that a different employer will someday enjoy the
fruits of its having done so (i.e., a worker encouraged to quit smoking
at 26 will cost less to insure when she's 46, but by that time will
probably be working at a different company).
And
Galston's first graf is just depressing and made me sad. Really. It's
high-school-level knowledge of the world, and Republicans deny it.
Daniels is not that dumb. But there's only one other thing he can be,
which is a liar, so he's that. When even these allegedly "reasonable"
Republicans spout such fantasy propaganda, what on earth are we to do?
Now,
a quick response to the comment threads. It's hilarious to me when
conservatives think they've "uncovered" the scandal that...I'm for
Obama! Yes. I am. My whole world view is a lot more complicated than
that, and in fact I believe right now that what this country needs more
than anything is more moderate Republicans, about which I've written and
will continue to write. But yes, I am for Obama. This is a real
stop-the-presses revelation, folks.
But
if you have any interest in being fair-minded, you will note that I
calls 'em as I sees 'em. Last week, I wrote three pieces in a row, three
in a row, laying into Obama. Go off and have a look and tell me how
many conservative columnists ever write three in a row attacking Romney.
And wingers, as a general principle, just get ahold of yourselves,
would you?
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