Science, Technology & Health: January 2007 Archives

I've considered this idea before, but I can understand why making it work would be pretty difficult: robots that build houses out of concrete.

The first prototype — a watertight shell of a two-storey house built in 24 hours without a single builder on site — will be erected in California before April.

A rival design, being pioneered in the East Midlands, with £1.2m of government funding, will include sunken baths, fireplaces and cornices. There are even plans for robots to supplant painters and decorators by spraying colourful frescoes at an affordable price.

By building almost an entire house from just two materials — concrete and gypsum — the robots will eliminate the need for dozens of traditional components, including floorboards, wooden window frames and possibly even wallpaper. It may eventually be possible to use specially treated gypsum instead of glass window panes.

Engineers on both projects say the robots will not only cut costs and avoid human delays but liberate the normal family homes from the conventional designs of pitched roofs, right-angled walls and rectangular windows.

“The architectural options will explode,” predicted Dr Behrokh Khoshnevis at the University of Southern California in Los Angeles, who will soon unleash his $1.5m (£940,000) robot. “We will be able to build curves and domes as easily as straight walls. ...

The researchers in Los Angeles claim their robot will be able to build the shell of a house in 24 hours. “Compared to a conventional house, the speed of construction will be increased 200-fold and the building costs will be reduced to a fifth of what they are today,” said Khoshnevis.

In addition to being faster and cheaper, the houses will probably also be far more durable than wood-frame structures, except against earthquakes.

Everyone knows how cool titanium is, so why is plain old steel still so popular? Because titanium can cost more than $40 per pound while steel is closer to $1 per pound. Fortunately Donald Sadoway from MIT has founded a company called Avanti Metal that is planning to use a new process that will drastically reduce the cost of refining titanium.

Now a startup, Avanti Metal, using technology developed at MIT, hopes to commercialize a process that drastically reduces the cost of producing titanium, making more of it available for large, lighter-weight airplanes. The process, developed by MIT chemist Donald Sadoway, applies an environmentally benign, direct electrolysis method to make the metal.

Titanium is naturally abundant. But processing titanium oxide found in the ground to make a usable metal is slow and produces toxic waste. "The price of titanium has gone through the roof," says Corby Anderson, director of the Center for Advanced Mineral and Metallurgical Processing at the University of Montana. "It's double what it was this time last year -- and last year it was pretty high."

Jeffrey Sabados, president of the four-person Avanti, estimates that, based on production plans published by Boeing and Airbus, there'll be a 30,000-ton shortage of titanium by 2010. He claims that Avanti's process for refining titanium could slash costs to about $3 per pound. Then, if the metal then sells for even $25 per pound, an estimate he calls conservative, it's a huge potential profit.

Ah, capitalism, is there anything it can't do? Plus, y'know, science and stuff.

Anyone who owns a pet will find this online version of the Merck Veterinary Manual incredibly useful for diagnosing and treating their pet before resorting to a veterinarian.

Just a note for for young women and parents with girls: the new HPV vaccine can prevent almost all cervical cancers and is recommended for all young females.

Females should be vaccinated against human papillomavirus (HPV) when they're 11 to 12 years old in order to prevent cervical cancer, new American Cancer Society guidelines recommend.

Other major health groups have also called for widespread vaccination in this age group.

In 2007, an estimated 11,150 cervical cancer cases will be diagnosed in the United States, and about 3,670 women will die from the disease, the society noted. Almost all cervical cancers are causally related to HPV.

This is a major advance in the battle against cancer that every woman should hear about and take advantage of.

Aviation Week has a pair of articles about the F-22 Raptor. The first describes how the F-22 and its partners benefit from its netcentric operations capabilities, explaining how the plane achieved 144 kills and no losses against older air-to-air fighters.

Perhaps the most important revelation by the 27th Fighter Sqdn. was demonstrating the F-22's ability to use its sensors to identify and target enemy aircraft for conventional fighters by providing information so they could engage the enemy sooner than they could on their own. Because of the advanced situational awareness they afford, F-22s would stick around after using up their weapons to continue providing targets and IDs to the conventional fighters. ...

"When I look down at my scope and put my cursor over a [friendly] F-15 or F/A-18, it tells me who they are locked on to," he says. For example, "I could help them out by saying, 'You're double-targeted and there's a group over here untargeted' . . . to make sure we got everybody." F-15 targets will be latent because of the radar sweep.

However, these messages are less and less verbal. "When you watch [tapes of the Alaska] exercise, it's fairly spooky," says Gen. Ronald Keys, chief of Air Combat Command. "There's hardly a word spoken among Raptor pilots." That silence also previews some of the fighter's possible future capabilities.

"Because of the way the aircraft was designed, we have the capability to do more," Keys says. "We can put unmanned combat aircraft systems in there with Raptor. You've got three fairly low-observable UCAS in the battlespace. An air defense system pops up, and I click on a UCAS icon and drag it over [the emitter's location] and click. The UCAS throttles over and jams it, blows it up or whatever."

As many others have written about at length, battles of the future will be won by superior networks, not merely superior weapons platforms. Even still, the second article indicates that the Raptor is also a better fighter than previous generations of fighters, such as the F-15.

However, the question periodically resurfaces about whether the F-22 could hold its own during a within-visual-range fight with a very maneuverable fourth-generation fighter such as the Sukhoi Su-27 and Su-30, Eurofighter or Dassault Rafale. The answer will never be obvious to an outsider. The Raptor's high-angle-of-attack capabilities are part of the formula of classified tactics that are closely held. But, roughly, its unique maneuvering and nose-pointing options--plus the high off-boresight capabilities of the AIM-9X missile, which is to be added about 2010--give the aircraft previously unheard-of means of quickly shooting down a foe.

Nonetheless, chasing an F-22 in a two-seat F-15D--which carried reporter Michael J. Fabey--provided perspective about their comparative capabilities. A recent flight started with F-15 pilot Capt. Andy (Bishop) Jacob flying alongside an F-22 piloted by Maj. Shawn (Rage) Anger in the air-to-air ranges above Tyndall AFB, Fla.

Opponents of further Raptor procurements argue that going by such basic flight physics as thrust-to-weight ratios, rearward cockpit visibility and simple aircraft size, the F-22 ranks below the F-15 and other earlier fighters.

Aerial engagements like the encounter between Anger and Jacob are supposed to help prove the Raptor's case. Still, one argument offered by F-22 opponents is that the jet's reported victories over F-15s are often scripted and unreliable gauges of Raptor superiority. ...

Anger and Jacob had planned to engage in mock combat. However, a flashing indicator light warned that something could be wrong with the F-22. But the flight was enough to make a believer of Jacob. "Maybe, with some tricks or tactics, I can beat it," he said. "But that would be a one-time set of circumstances. As for a Raptor-beating tactic--there's no such thing."

With a price tag between $100 million and $200 million per aircraft, they'd better be good. Hopefully the Raptor is intimidating enough that none of our enemies will try to find out.

If you've ever wondered why astronomy uses strange units like the AU (astronomical unit) and the solar mass, here's the answer.

Until recently, neither the AU nor the gravitational constant were precisely known. However, a determination of the relative mass of another planet in the Solar System or of a binary star in units of solar masses does not depend on these poorly known constants. So it was useful to express these masses in units of solar masses (see Gaussian gravitational constant). Today, the AU is extremely well measured using interplanetary radar and G is well measured, but the solar mass persists as one of astronomy's arcane historical conventions.

Basically, it was easy to calculate the relative mass of one object compared to another even though no one had a precise value for the gravitational constant or the distance between the earth and the Sun. However, even though we now know that we these values to high precision we're still stuck with the old units of measurement.

An article about British moon exploration begs the question:

Britain could send its first un-manned mission to the moon by 2010 to study the lunar surface and find the best site for humans to inhabit, the BBC has reported.

A report by Surrey Satellite Technology Ltd., a top British space company, found the cost of space travel had fallen enough to let the government consider such a probe, it said.

Why has the cost of space travel fallen enough for Britain and even China to consider moon missions? Because of one of the many invisible subsidies that America provides to the world free of charge: technological advancement. The world owes America an enormous debt for the knowledge we generate and the free dissemination we encourage, in addition to other invisible subsidies like military protection under the (fading) pax Americana.

Also from reader JV, a nifty little tutorial on extracting AAA batteries from a 9V.

With a needlenose pliers, gently peel away the metal cover of the 9 volt battery. It should separate along the seam without much effort. Be careful though, because the metal edges can be sharp!

I remember thinking at one point that a 9 volt battery was just a small box full of acid or something, but as you can clearly see, this one is is just constructed of six smaller 1.5 volt cells wired in series.

I'm sure this will come in handy at some point in my life.

In a development almost certain to create more worry than good, a clinic called Genetic Health is offering personalized genetic exams that will pinpoint an individual's areas of risk.

Dr Jenkins, a consultant physician at St Bartholomew's Hospital, London, is one of the expert medical team behind Genetic Health, a clinic that's just opened to identify those variations in your genes that have implications for your health.

It's well known that having some rare gene variations can put you at very high risk of certain diseases. For instance, if a woman has the faulty version of the BRCA1 gene she is 85 per cent more likely to develop breast cancer, and up to 40 per cent more likely to develop ovarian cancer.

Patients can be tested for these specific single genes. This new test is different - it pinpoints the group of genes linked with chronic diseases such as Alzheimer's and some cancers. The genes are not a death sentence, they just make a particular disease more or less likely depending on how you behave.

They can affect how flexible your arteries are, your chances of having raised blood pressure, how likely you are to age gracefully and whether you are doomed to feel hunger more keenly and lay down fat more easily. You can even discover how well you metabolise medication, and your chances of suffering from side effects.

And so forth. There are many things I'd personally like to know about myself, but I think I'm more stoic than the general population. I'm not sure that an average patient would be better off knowing their genetic fate. I don't think I'd be better off, it would just be kinda fun.

I've long wondered why the shortest day of the year is not also the coldest, and USA Today offers an explanation that sounds wrong to me.

We could think of the air in such a place as being like a bank account. If you add money to a bank account, it grows. If you add heat to air it warms up. The Earth is always losing heat, like a bank account that you're always taking some money from. If the amount of heat arriving from the sun is exactly equal to the amount leaving, the temperature stays the same.

As days grow longer in spring and early meteorological summer, the balance tips to more heat arriving than leaving. This is like adding money to the account faster than you are withdrawing it. The air grows warmer and warmer. On the longest day, the amount of heat arriving is greatest. But, even after the days begin growing shorter, the amount of heat arriving is more than the amount leaving. It's like continuing to add more money to the bank account than you're taking out, even though you are adding less than you were before.

Sometime in the late summer or during the fall, depending on how far north of the equator you are, the heat "account" is in balance. From then on, more heat is leaving than arriving and the days grow colder. Now, you're taking out more than you're adding to the account.

In December, when days are shortest, the "withdrawals" from the heat account are greatest. But even after the days start growing longer, more heat is leaving than arriving. The heat account is growing smaller, even though less heat is leaving. Eventually, however, you arrive at a day when the amounts of heat leaving and arriving are in balance. Then, the amount of heat being put into the account becomes greater than the amount being withdrawn. The air begins warming up.

Why does this explanation strike me as wrong? Because everyone knows that air doesn't take months to warm or cool. Every day the air gets warmer, and every night it gets cooler, often swinging by tens of degrees in a few hours. It doesn't make any sense to claim that air can warm from 32 degrees at 6am to 65 degrees at 1pm, but that the daily high takes months to migrate from 40 degrees to 60 degrees.

The temperature at any given moment appears to be directly tied to how long the sun has been up... but still, the coldest day of the year isn't the shortest, nor is the hottest the longest. There must be more going on than I'm aware of, and I don't think the "bank account" explanation covers it.