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Philips Creates Shopping Assistant with LEDs and Smart Phone

If you're like me, fumbling around the supermarket looking for obscure items is a pretty common—and frustrating—occurrence. Lighting giant Philips has developed a solution: smart lights.

The company yesterday introduced a system that connects in-store LED lights with consumers' smart phones. Using a downloadable app, people will be able to locate items on their shopping lists or get coupons as they pass products on the aisles. Retailers can send targeted information such as recipes and coupons to consumers based on their precise location within stores, while gaining benefits of energy-efficient LED lighting, says Philips.

“The beauty of the system is that retailers do not have to invest in additional infrastructure to house, power and support location beacons for indoor positioning. The light fixtures themselves can communicate this information by virtue of their presence everywhere in the store," said Philips Lighting's Gerben van der Lugt in a statement.

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A Visit to the Magnetic Monopole Lab

One year ago this month, a physics lab in Amherst, Mass. came the closest yet to something physicists have been chasing since it was proposed in 1931—a magnetic monopole, an entity containing pure magnetic "charge" like an electron contains pure electric charge. The researchers have made the first so-called “Dirac monopole.” (The name comes from the physicist Paul A.M. Dirac, who described monopoles interacting with a quantum field, which is what the Amherst experiment was the first to do.)

Despite some sensationalistic media coverage that might have suggested otherwise, no one saw an actual particle that carried its own magnetic “charge.” Natural magnetic monopoles, whose existence if confirmed would have the benefit of explaining why electric charge is quantized, have still never been observed.

Instead what Amherst College physics professor David Hall and his postdoctoral researcher Michael Ray, created was an analog of a magnetic monopole in a collection of ultracold cloud of rubidium atoms known as a Bose-Einstein condensate. Consider their quasi-magnetic monopole, Hall says, as being a little like an electron “hole” in a semiconductor. In a lattice of atoms like doped silicon, the absence of an electron behaves much like a particle itself, propagating down the lattice as if it were the positively-charged twin of the electron. And of course holes aren’t actual particles. So, neither, are these quantum monopoles.

“We’ve created a magnetic monopole, but it’s just not in a magnetic field that a compass would respond to,” Hall says. “It’s a different field, a synthetic field or an emergent field, which we actually have a lot of control over.” An actual magnetic monopole particle would have two important properties—a quantum wavefunction describing the probability that it would be found in any point in space—and the magnetic field the particle generates. The Amherst monopole's "wavefunction" is just the density of the Bose-Einstein condensate. The probability density of a monopole particle's quantum state, in other words, is directly analogous in this system to the physical density of condensate. Following the experiment's analogy, then, the magnetic field of the "monopole" is represented by the orientation of atomic spins in the condensate. Thus both quantum and magnetic fields of the monopole analogue are found in this experiment, making it an attractive medium for further study and perhaps one day the capture and study of a real, honest-to-goodness magnetic monopole particle.

To create the condensate, Hall and Ray as well as the recently graduated Amherst student Saugat Kandel worked in collaboration with a team of Finnish researchers to laser-cool and magnetically-cool a cloud of rubidium atoms in their basement lab on the Amherst College campus.

They did it again for IEEE Spectrum last week [see video].

In one atomic trap they cooled the rubidium atoms down to microKelvins, millionths of degrees above absolute zero. Then shuttling the cooled cloud down a tube a meter or so away to a second trap, they further cooled the atoms by evaporation—shunting away all but the stillest of atoms in their increasingly frigid cloud. The overall effect, then, was to create a cloud that was 10 to 100 billionths of degrees above absolute zero—nanokelvins, in other words.

And at this temperature nature behaves quantum mechanically, even in the macroscopic realm. The Bose-Einstein Condensates, subject of the 2001 Physics Nobel Prize, can be manipulated and moved around with zero viscosity, a property called superfluidity.

Creating the “monopole,” from the condensate, involves a few extra steps they couldn’t show us. Hall says a powerful infrared laser is turned on to trap the condensate cloud. (The tool is a familiar one, called optical tweezers.) Then the magnetic field that once kept the cloud in place is free to manipulate the condensate.

And it is this magnetic field,  that can finally knead, twist and bend its extremely supple subject, the condensate, so that it can simulate the presence of a “particle” of magnetic charge in its midst. [See the other video.]

Jonathan Morris, visiting assistant professor of physics at Xavier University in Cincinnati, described in IEEE Spectrum in 2013 his own group’s work creating quasi-magnetic monopoles in atomic networks of linked spins called “spin ices.” Morris says the qualifier “quasi” is important to stress in both discoveries.

“I doubt that particle physicists will consider these as fundamental magnetic monopole particles and they will continue in their search for such objects,” Morris told IEEE Spectrum’s Rachel Courtland. “The authors of this new study distinguish between their emergent magnetic monopole and the magnetic monopole particle by calling the latter a ‘natural magnetic monopole’ just as we distinguished between the spin-ice monopoles by saying that we had entities that ‘resembled magnetic monopoles,’" he says.

[The spin-ice monopoles are explained in this video.]

To Hall, the Bose-Einstein condensate's quantum properties are the reason his group's experiment is a noteworthy complement to  previous groups' ersatz monopoles. "We have access to the analog of the electronic wavefunction," Hall says. "That’s something that no other system has. So we can study the analog of the electron-monopole interaction—how the system behaves once we’re done creating it." Moreover, he says, "If you think of our condensate/superfluid as a kind of 'monopole detector' then of course we might learn more about how to efficiently detect natural magnetic monopoles, or what their signatures might be."

This article was updated on 19 February 2014.

Smart Mortar Rounds Make Good Spies

CORRECTION: ST Kinetics informs us that the 40-mm munition is not technically a mortar round. It has a smaller caliber than a mortar. 

Long a staple of the infantry unit, the 40-millimeter round comes in many shapes and functions: low and high velocity, training, green, non lethal, and whatnot. The large volume of the round itself has prompted a manufacturer to think outside the box and consider this popular standard as a projectile with a payload. 

ST Kinetics, a defense subsidiary of the Singapore Technologies conglomerate, has devised a couple of interesting tricks. The coolest gimmick ST Kinetics pulled is with a round called SPARCS, or Soldier Parachute Aerial Reconnaissance Camera System. The round will usually climb 150 meters and travel down range about that same distance, then deploy a small camera that gently falls from the sky via parachute while transmitting images to a ground unit. The photos are are then stitched into a bigger and higher resolution version that can be shared and zoomed. 

It's the kind of thing a drone is usually called in for, but a mortar round is smaller, more expendable, and does the job with an immediacy that's hard to match.

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Singapore’s $300-Million Air-Traffic Automation System Unveiled

As the plane carrying your correspondent from Hong Kong to Singapore started its descent to the Changi airport, the worlds fifth busiest, it started flying circles. Shortly afterwards, the captain explained that multiple aircrafts were on holding pattern and the queue was changing quickly. That, I was assured, had nothing to do with the official launch of the airports new US $300-million air traffic control system. Instead, the delay was due to the final day of the Chinese Lunar New Year holidays, and it probably would have been a lot worse without the new system.

Soft launched in October and jointly developed by French engineering firm Thales and Singapores aviation authorities, LORADS III is the latest iteration of a proven air traffic control system called TopSky-ATC. And its main strength is that it gives controllers better information, faster. 

To understand how, you have to remember that air traffic control actions in many places are still done by recording flight dataairplane call signs, speed, bearing, altitude, and other informationon strips of paper, and instructions. 

Like all modern ATC systems, LORADS III does without paper strips. Thats all been digitized, but Thales is looking at doing without strips altogether, paper or digital: the ideas is to move towards much richer labels and a management system that give at a glance a clearer, more complete picture of the congestion status of a given airspace.

Hovering the mouse over each track symbol allows the controller to see a plethora of data and issue commands that can get relayed to the aircraft via satellite. The new commands pop up in the on board navigation and communication instruments  and the pilot can decide whether to implement it or not. (They usually do, unless they have a good reason not to—they are too heavy to climb to a higher level or they are cruising already at their fastest, for example.)

Usually these commands are radioed in when in radio range and its fair to assume they still will be for some time but this sort of command-by-text-messaging would reduce controllers workload, according to Thales. This will also reduce the radio chatter, which at busy airports and on certain frequencies is up to capacity and represents a bottleneck for more efficient operations. For control of the skies over oceans its even more important. Long distance communications between ground controllers and aircrafts goes over HF radio, notoriously finicky and with a range that depends on weather conditions. Controllers can instead transfer small amounts of data via satellite or by HF or VHF radios, because, as anybody trying to make a call on a busy cell network has noticed, its much easier to slip a small text message through, than place a voice call. 

The commands and subsequent execution, together with key flight data are stored in a central system called the Flight Data Processor, which calculates in real time everything pertaining to the position and trajectory of each aircraft. Every work station is connected to it, so all controllers have an up-to-date view of whos going where and how fast. 

 “It a simple change, but its also very complicated, because there are more than a hundred positions in the Singaporean Traffic Center and training facilities, says Andrew Nabarro, business development manager for air operations at Thales. Now, each person can have access to customized information at different times.

The first step, though, is knowing where aircraft are. This involves both active and passive sensing. Airplanes beam out their name, location, route and whatnot through an ADS-B feed, or automatic dependent surveillance broadcast. ADS-B is a type of transponder that beams out the GPS position of the aircrafts about once per second. 

Theres radar too, of which there are two kinds: primary radar sends out a burst of energy and waits for a reflection from an aircraft. Secondary radar instead interrogates a receiver placed aboard the airplane, which in turns answers with its identifier and altitude. Secondary radar has a longer range, about 250 nautical mile (460 kilometers); primary reaches less than half that distance.  But primary works with any type of aircraft whether or not theyve been equipped with the transmitter needed for secondary radar.

LORADS III has to make sense of all those signals to come up with a single set of information about the aircraft above Singapore. Thalesproprietary solution, called Multi Sensor Track Processing, takes all the different tracks from all the different radar, many ADS-B receivers, many wide area multilateration receivers, which is another type of surveillance, and turn it all up and says of all the sensors that we have, this is the actual position of the aircraft,says Nabarro.

Most air-traffic control systems are customized to manage a particular type of airspace; there are approach airspaces (think the area above and around a major airport) and en route ones (the skies of the North Atlantic, through which the bulk of Europe to U.S. traffic flies). Singapore, by virtue of its position in the middle of the Kangaroo routeconnecting the UK and Europe to Australia and several South East Asian countries, happens to need a system that can do both. The portion of sky under Singapores control covers an area of three quarters of a million square kilometers and its controllers preside over 220 000 annual movements. 

As the deluge of flights approaches for arrival at Singapore, the systems Arrival Manager kicks in. So instead of having a human being trying to sequence a whole bunch of airplane coming from all sorts of directions, at different speeds and altitude, the system will calculate the best sequence, says Nabarro. Here, bestmeans the sequence that gives the least amount of holding time for everybody.

Holding costs airlines thousands of dollars per flight in wasted fuel. Usually, airplanes begin their descents from cruise level when they are about a hundred nautical miles (185 kilometers) from the airport, but they only learn of congestion as they get closer and reach a much lower altitude. At low altitudes, jet engines are much less efficient. With the Arrival Manager, controllers are able to tell approaching but still cruising airplanes to slow down or speed up a bit in order to sequence them in a way that reduces low-altitude holding. The order can, of course, be changed manually and the system will then recalculate the best sequence, showing the relevant controller what commands must be sent to which aircraft, in order to minimize disruptions to the flow of approaches. 

But whats good software, without the ability to back all the data up? The main system has a dual, fully redundant set of servers that make the Changi control room fail safe; controllers can switch from one to the other simply pressing a button. While this has been implemented before, Singapore officials wanted another layer of safety: at a neighboring training facility, theres a replica of the control room with yet another set of dual servers. This second set runs simulations for training of new controllers, but with minimal software tweaking it could be transformed into a fully autonomous back up control room, if anything catastrophic were to happen to main one. The two locations are a few kilometers apart, providing an added layer of strategic safety, as well.

Laser Link to Moon Trumped NASA and MIT Engineers’ Expectations

In October of last year, a team from NASA and MIT’s Lincoln Laboratory made space communications history by beaming data, via laser, at speeds reaching 622 megabits per second, to Earth from a spacecraft orbiting the moon. Radio-frequency systems used for space communications today are usually tens of times slower.

NASA and Lincoln Lab engineers tested this first-ever two-way laser link between the moon and the earth, dubbed the Lunar Laser Communication Demonstration (LLCD), for about a month. And, as it turns out, the test was underwhelming: no jaw-clenching, fingernail-biting, arm-clutching moments. In other words, an engineer’s dream.

“It worked like gangbusters,” says Don Boroson, who led the LLCD design team at Lincoln Lab, and presented the demo’s results at the SPIE Photonics West conference on 3 February.

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China's "Jade Rabbit" Moon Rover Awakens With Same Problems

China's lunar rover is not ready to say "good night moon" just yet. The rover, called Jade Rabbit, has awakened from the long lunar night—but only after Chinese state media reported of its death. This gives Chinese mission controllers another chance to figure out the rover malfunction that first led to fears of its untimely demise.

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What You Need to Know About Mt. Gox and the Bitcoin Software Flaw

Here's what a terrible week looks like in the world of Bitcoin: Two of the most trafficked Bitcoin exchanges, Mt. Gox and Bitstamp, temporarily halt trading and suspend bitcoin withdrawals in the midst of a distributed denial of service attack (DDoS). On exchanges that are still open for business, the value of the currency takes a brutal, sudden hit and then continues to tumble. Bitcoin users notice strange errors in their wallet balances after making routine transactions. Rumor spreads that the Bitcoin protocol is critically flawed. And where rumor is lacking, conspiracy theories abound.

All this, and it's barely Thursday.

Some of it is true. Some of it is half true. Some of it is completely false. Here is what's really going on.

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National Ignition Facility Achieves Record Energies

Big fusion milestones are rare things. But a team based at the National Ignition Facility (NIF) says they've reached one. For the first time, they've been able to get their deuterium-tritium fuel to fuse so that it produces more energy than was deposited into it.

The researchers are quick to note they've not achieved the long-awaited goal of ignition—a self-sustaining fusion reaction that produces more energy than what is sent into the experiment. Most of the 1.8 megajoules of energy in the facility's lasers is still lost in the effort to achieve the temperatures and pressures needed to get fusion started. This process involves hitting the inside of a cylindrical gold container with 192 lasers in order to produce X-rays. That radiation then heats and blasts away the outer layer of a spherical capsule suspended at the center of the cylinder. The reaction force sends the remainder of this target inwards, compressing some 170 micrograms of frozen deuterium-tritium fuel at the center.

Today only about 1 percent of the energy poured into the cylinder actually winds up in the fuel. Still, team leader Omar Hurricane told reporters in a press briefing on Monday that this latest milestone is "kind of a major turning point in a lot of our minds." The results are published this week in a paper in Nature(A similar announcement was made in August of last year, when some 8000 joules of energy were released in the form of neutrons. In this paper, the team reports yields as high as 17 000 joules.)

The team is also encouraged by evidence of what's called alpha particle heating—a process by which helium atoms created in fusion reactions deposit their energy into the fuel instead of escaping. This "bootstrapping" process—using fusion to create more fusion—is what will be needed to ultimately get the yield up to ignition levels.

NIF has been taking a more research-oriented approach to fusion since late 2012, when the facility wrapped up the National Ignition Campaign, aimed at achieving ignition in just two years. The laser shots fired during that campaign tended to have what's called a "low-foot"—the laser power began at low power and was then ramped up. This approach made target compression fairly easy, but it created instabilities and asymmetries that sap power out of the compression process. "Those early implosions tended to rip themselves apart," Hurricane told reporters on Monday.

He and his colleagues took what might be called a step back, experimenting with "high-foot" pulses. These laser shots start out at high power, which quickly raises the temperature of the capsule. This approach makes capsule shells harder to compress, but also increases the speed at which layers are blasted off the capsule, which helps stop instabilities from growing. "Those two effects act together to make it more stable," Hurricane said. 

The team is now exploring ways to increase the yield even further with adjustments to capsule design.

In terms of yield, NIF is still behind the magnetic confinement approach pursued by experiments such as the Joint European Torus (which currently holds the record), Steven Cowley, director of the UK's Culham Centre for Fusion Energy, told IEEE Spectrum in an email. But he adds both approaches are now finally, after 60 years, getting "close" to controlled fusion. "We must keep at it."

A Hearing Device With No Stigmatizing External Hardware

Cochlear implants are among the most successful hearing devices out there. They have been around for about 30 years and more than 220 000 people worldwide enjoy restored hearing because of them. But they require clunky hardware mounted onto the skull and behind the ear that limit their use in the shower and often stigmatize the people who wear them. But this week, a team of scientists will present a new, alternative design that eliminates all the external hardware of the traditional cochlear implant and allows it to be charged wirelessly with a smartphone. 

The key to the new design is an implantable low-power signal-processing chip developed by Anantha Chandrakasan and his colleagues at MIT in Cambridge, Mass. The team cleverly integrated its microchip with an implantable piezoelectric sensor, and has tested the system in a human cadaveric ear. They will present their paper this week at the International Solid-State Circuits Conference in San Francisco. (Chandrakasan is the same researcher who in 2012 demonstrated how to harvest energy from the middle ear.)

Chandrakasan's new device works like this: A piezoelectric sensor mounted at the umbo in the middle ear picks up sound. That signal, a measure of the sound-induced motion of the umbo, travels to the microchip implanted elsewhere in the ear, where it is conditioned, digitized and processed. The chip then converts the signal to electrical waveforms and pumps them to electrodes implanted in another part of the ear called the cochlea. The waveforms received by the electrodes stimulate auditory nerve fibers and make the sound audible to the user. The device can be charged wirelessly in just a couple of minutes using a mobile phone and special adapter.

The design would be a huge improvement over existing cochlear implants, which require the user to wear the external components—mainly for power—at all times.

Researchers elsewhere have been working on alternatives to today's cochlear implants as well. In 2012, Darrin Young at the University of Utah designed a MEMS-accelerometer-based middle ear microphone that also moves all the external components of the cochlear implant inside the body. But Young's sensor draws a few milliwatts of power—more than MIT's design. An implanted rechargeable battery will be required. Young says his team is working on improving the prototype. "We are expecting a further power reduction by at least a factor of 20. This will bring down the power below 100uW," he said.

Further work, particularly on the sensor component, is needed before MIT's chip is ready to be implanted in a human. The geometry of the sensor still needs to be optimized, as does the method of stabilization, says Konstantina Stankovic at Harvard Medical School, who collaborated on the project. "A tricky thing with the implantable sensors has been stable placement and avoidance of sensing bodily noise," she says.

Now on Google Earth: 150 Years of Global Temperature Data

The Climate Research Unit (CRU) of the University of East Anglia has made its worldwide historical record of over-land temperature data available as an overlay on Google Earth. (And non-KML, comma-delimited temperature data files, along with many other kinds of climate records, are available at http://www.cru.uea.ac.uk/data.) The CRU Temperature database, version 4 (CRUTEM4) includes information from some 6000 weather stations, with some time series reaching back to 1850.

The big new data sets may leave some people cold. Others, though, look forward to poring over gigabytes of new information with the glee of Scrooge McDuck diving into a pile of gold doubloons.

The CRUTEM4 Google Earth data is provided in Keyhole Markup Language (KML is named after its developer, Keyhole, Inc., which was acquired by Google). The CRUTEM4 KML schema divides the Earth’s land surface into 780 grid boxes, each 5 degrees latitude by 5 degrees longitude. Users can click any box to see temperature information for that area: options include year-by-year variations (called “anomalies”) from historical means, tracing changes in annual and seasonal average temperature. By default, these consolidated data are “homogenized”—processed to emphasize variations above and below the mean, without noting what that mean temperature might be. The un-normalized temperature data are, however, available at a deeper level: users can drill down to see annual and seasonal temperature data for each individual weather station—like, for example, the station at Krasnaya Polyana, in the mountains near Sochi, Russia, where many Winter Olympics events are now underway.

CRUTEM’s curators, the University of East Anglia’s T.J. Osborn and P.D. Jones, describe CRUTEM and the Google Earth expansion in an Earth Systems Science Data paper. They go into detail on the mechanics and rationale of homogenization—sometimes extensive adjustments needed to compensate for missing data, suspect data, and systematic variations (e.g., changing the method of temperature measurement or moving the measuring station to a different altitude).

CRUTEM4 is the latest in a series of CRUTEM incarnations dating back to 1986. This release, offering increased transparency of the data, may be of particular interest because Osborn and Jones were among the climate researchers embroiled in controversy following the release of stolen CRU e-mails in 2009 and 2011. Widespread accusations, surfacing first among bloggers who resist the idea of climate change, charged climatologists at CRU and elsewhere with trying to derail the peer review process and stifle opposing views. Subsequent investigations by University of East Anglia, Pennsylvania State University, and the House of Commons, among others, largely exonerated the “pro-warming” researchers of wrongdoing, but the brouhaha did succeed in tarnishing reputations of climatologists whose work indicates global warming, and burnishing the rhetoric, if not the substance, of climate-change deniers.

Though there had been speculation that the e-mails had been stolen by a disaffected person inside the University of East Anglia, British police concluded in July 2012, that “the hack was the work of ‘sophisticated’ outsiders, not a whistleblower at the university,” according to The Guardian. Authorities nonetheless closed the case, because, they said, they did “not have a realistic prospect of identifying the offender or offenders and launching criminal proceedings within the time constraints imposed by law.” 

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