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SpaceX, the American space transport company founded by PayPal and Tesla Motors co-founder Elon Musk, has announced a late 2013 or 2014 launch date for the world's most powerful rocket, the Falcon Heavy. Overshadowed by only the Saturn V moon rocket that was decommissioned after the Apollo program, the Falcon Heavy will be able to carry payloads of 53 metric tons (117,000 pounds or 53,070 kg) into orbit, which is more than the maximum take-off weight of a Boeing 737-200 loaded with 136 passengers, luggage and fuel.

The first of the Falcon Heavy's two stages is made up of three nine-engine cores that are used as the first stage of the Falcon 9 rocket. For the Falcon Heavy, the Merlin engines have been upgraded and are currently being tested at SpaceX's development facility in McGregor, Texas. Like a commercial airliner, each engine is surrounded by a protective shell to contain a fire or chamber rupture and prevent it from affecting other engines or the vehicle itself.

At liftoff the 69.2m (227 ft) long Falcon Heavy will generate 3.8 million pounds of thrust, which is equivalent to the thrust of fifteen Boeing 747's taking off at the same time. SpaceX says this gives it more than twice the performance of the next most powerful vehicle, the Delta IV Heavy operated by the Boeing-Lockheed Martin joint venture United Launch Alliance. SpaceX also says that with more than twice the payload of the Delta IV but at one third the cost, the Falcon Heavy sets a new world record in terms of economy at approximately US$1,000 per pound to orbit.

"Falcon Heavy will carry more payload to orbit or escape velocity than any vehicle in history, apart from the Saturn V moon rocket, which was decommissioned after the Apollo program. This opens a new world of capability for both government and commercial space missions," said Musk.

To achieve performance comparable to a three-stage rocket the Falcon Heavy will be the first rocket in history to do a propellant cross-feed from the side boosters to the center core, which leaves the center core with most of its propellant after the side boosters separate. Crossfeed can also be turned off when it is not required, such as for missions below 100,000 pounds (45,359 kg).

Source: GizMag

 

"It's an important tool for us to continue dealing with an ongoing terrorist threat," Obama said Friday after a meeting with French President Nicolas Sarkozy.

With Obama in France, the White House said the president used an autopen machine that holds a pen and signs his actual signature. It is only used with proper authorization of the president.

Congress sent the bill to the president with only hours to go on Thursday before the provisions expired at midnight. Votes taken in rapid succession in the Senate and House came after lawmakers rejected attempts to temper the law enforcement powers to ensure that individual liberties are not abused.

The Senate voted 72-23 for the legislation to renew three terrorism-fighting authorities. The House passed the measure 250-153 on an evening vote.

A short-term expiration would not have interrupted ongoing operations but would have barred the government from seeking warrants for new investigations.

Congress bumped up against the deadline mainly because of the stubborn resistance from a single senator, Republican freshman Rand Paul of Kentucky, who saw the terrorist-hunting powers as an abuse of privacy rights. Paul held up the final vote for several days while he demanded a chance to change the bill to diminish the government's ability to monitor individual actions.

The measure would add four years to the legal life of roving wiretaps, authorized for a person rather than a communications line or device; court-ordered searches of business records; and surveillance of non-American "lone wolf" suspects without confirmed ties to terrorist groups.

The roving wiretaps and access to business records are small parts of the USA Patriot Act enacted after the Sept. 11, 2001, attacks. But unlike most of the act, which is permanent law, those provisions must be renewed periodically because of concerns that they could be used to violate privacy rights. The same applies to the "lone wolf" provision, which was part of a 2004 intelligence law.

Paul argued that in the rush to meet the terrorist threat in 2001 Congress enacted a Patriot Act that tramples on individual liberties. He had some backing from liberal Democrats and civil liberties groups who have long contended the law gives the government authority to spy on innocent citizens.

Sen. Dick Durbin, D-Ill., said he voted for the act in 2001 "while ground zero was still burning." But "I soon realized it gave too much power to government without enough judicial and congressional oversight."
Sen. Mark Udall, D-Colo., said the provision on collecting business records can expose law-abiding citizens to government scrutiny. "If we cannot limit investigations to terrorism or other nefarious activities, where do they end?" he asked.

"The Patriot Act has been used improperly again and again by law enforcement to invade Americans' privacy and violate their constitutional rights," said Laura W. Murphy, director of the ACLU Washington legislative office.

Still, coming just a month after intelligence and military forces tracked down and killed Osama bin Laden, there was little appetite for tampering with the terrorism-fighting tools. These tools, said Senate Republican leader Mitch McConnell of Kentucky, "have kept us safe for nearly a decade and Americans today should be relieved and reassured to know that these programs will continue."

Intelligence officials have denied improper use of surveillance tools, and this week both FBI Director Robert Mueller and Director of National Intelligence James Clapper sent letters to congressional leaders warning of serious national security consequences if the provisions were allowed to lapse.

The Obama administration says that without the three authorities the FBI might not be able to obtain information on terrorist plotting inside the U.S. and that a terrorist who communicates using different cell phones and email accounts could escape timely surveillance.

"When the clock strikes midnight tomorrow, we would be giving terrorists the opportunity to plot attacks against our country, undetected," Senate Majority Leader Harry Reid said on the Senate floor Wednesday. In unusually personal criticism of a fellow senator, he warned that Paul, by blocking swift passage of the bill, "is threatening to take away the best tools we have for stopping them."

The nation itself is divided over the Patriot Act, as reflected in a Pew Research Center poll last February, before the killing of bin Laden, that found that 34 percent felt the law "goes too far and poses a threat to civil liberties. Some 42 percent considered it "a necessary tool that helps the government find terrorists." That was a slight turnaround from 2004 when 39 percent thought it went too far and 33 percent said it was necessary.

Paul, after complaining that Reid's remarks were "personally insulting," asked whether the nation "should have some rules that say before they come into your house, before they go into your banking records, that a judge should be asked for permission, that there should be judicial review? Do we want a lawless land?"

Paul agreed to let the bill go forward after he was given a vote on two amendments to rein in government surveillance powers. Both were soundly defeated. The more controversial, an amendment that would have restricted powers to obtain gun records in terrorist investigations, was defeated 85-10 after lawmakers received a letter from the National Rifle Association stating that it was not taking a position on the measure.

According to a senior Justice Department national security official testifying to Congress last March, the government has sought roving wiretap authority in about 20 cases a year between 2001 and 2010 and has sought warrants for business records less than 40 times a year, on average. The government has yet to use the lone wolf authority.

But the ACLU also points out that court approvals for business record access jumped from 21 in 2009 to 96 last year, and the organization contends the Patriot Act has blurred the line between investigations of actual terrorists and those not suspected of doing anything wrong.

Two Democratic critics of the Patriot Act, Sen. Ron Wyden of Oregon and Udall of Colorado, on Thursday extracted a promise from Senate Intelligence Committee chairman Dianne Feinstein, D-Calif., that she would hold hearings with intelligence and law enforcement officials on how the law is being carried out.

Wyden says that while there are numerous interpretations of how the Patriot Act works, the official government interpretation of the law remains classified. "A significant gap has developed now between what the public thinks the law says and what the government secretly claims it says," Wyden said.

Author: JIM ABRAMS - Associated Press writers Laurie Kellman and Pete Yost contributed to this report.

 

Issues Covered:

1) TZM Global Radio Show, Wed. May 25th 2011
2) The Zeitgeist Media Festival, Global/Main Event (Sept 9th - 11th 2011)
3) TZM Regional, Monthly "TownHalls", Global.

***

1) TZM GLOBAL RADIO:

This Wed. May 18th at 4pm EDT Tom Williams of TZM UK will host The Zeitgeist Movement's Global Radio show.

www.blogtalkradio.com/zmglobal

www.thezeitgeistmovement.com/joomla/index.php?option=com_content&view=article&id=438&Itemid=1904&lang=en

About: ZM Global Radio is a weekly radio show presented by various active coordinators of The Zeitgeist Movement in a rotational fashion. These broadcasts discuss the developments and aims of The Zeitgeist Movement.

2) THE ZEITGEIST MEDIA FESTIVAL:
(Sept 9th - 11th, 2011)

zeitgeistmediafestival.org/

Recognizing this power of Art to help change the world, “The Zeitgeist Media Festival” is an extension of The Zeitgeist Movement’s “Media Project”, which is currently an emerging, experimental online platform for socially conscious artistic expressions.

This event is modeled after our more intellectually oriented annual event day - “Zeitgeist Day” (www.zdayglobal.org/) - which has occurred for the past 3 years with 10s of thousands of participants in over 70 countries each year.

The Zeitgeist Media Festival is also partnering with local Food Drives globally to help the many homeless and suffering people in the world today.

-MORE INFO:
zeitgeistmediafestival.org/site/index-1.html

-SUBMISSIONS:
zeitgeistmediafestival.org/site/index-3.html

-LA MAIN EVENT:
Tickets for the Los Angeles, CA Featured Event will go on sale in late May. This non-profit event is an 8 hour long multi-media experssion featured a spectrum of socially conscious art. Confirmed commitments include Lili Haydn, The Lions, Natacha Atlas, Norton Wisdom, Master 0, Rick Overton and many others both local and national. Peter Joseph will also be performing abstracts of the Zeitgeist Film Series Score live.

zeitgeistmediafestival.org/site/index-2.html

3) TZM TOWNHALL MEETING, MONTHLY:

The Zeitgeist Movement's is now launching regional monthly Townhall Meetings. These are live, public events conducted by Official Regional ZM Chapters. These localized events are similar in function to our annual global "Zeitgeist Day" events but ideally occur monthly, rather than annually. Modeled after patterns proven effective by civil right's movements historically, the goal is to inform the public of TZM's understandings and goals and hence grow awareness and membership.


More:
www.thezeitgeistmovement.com/joomla/index.php?option=com_content&view=article&id=650&Itemid=100152&lang=en

~ZM

 

Turismo Associati note: THIS ARTICLE FROM THE ENGLISH NEWSPAPER THE GUARDIAN is dated: Thursday 10 February 2011 15.22 GMT. THIS COULD EXPLAIN THE CONNECTION WITH WHAT HAPPENED IN MAY 2011 TO Mr. STRAUSS-KAHN... 

Dominique Strauss-Kahn, managing director of the International Monetary Fund, has called for a new world currency that would challenge the dominance of the dollar and help curb future financial instability.

In a speech in Washington, Strauss-Kahn argued that the reserves that member countries held with the fund could be used, instead of the dollar, to price international trade. These so-called special drawing rights (SDRs) could also act as an alternative to the dollar in central banks' foreign currency reserves.

"Using the SDR to price global trade and denominate financial assets would provide a buffer from exchange rate volatility," he said, while "issuing SDR-denominated bonds could create a potentially new class of reserve assets".

The IMF published a policy paper backing Strauss-Kahn's views as it gathered top-level economists for discussions on the future of the international monetary system.

Strauss-Kahn, who has been tipped as a contender for the French presidency next year, also argued that the way SDRs were valued, which is currently based on a basket of currencies – the dollar, sterling, the euro and the yen – be broadened to include others such as the Chinese yuan.

International policymakers have become increasingly concerned about the threat of currency wars as struggling governments try to hold down their own exchange rates as they clamber out of recession.

Strauss-Kahn admitted that there were formidable hurdles to achieving a greater role for SDRs, but he warned that without urgent action, the simmering conflicts in the international financial system could tip the world back into chaos.

"Global imbalances are back, with issues that worried us before the crisis—large and volatile capital flows, exchange-rate pressures, rapidly growing excess reserves – on the front-burner once again. Left unresolved, these problems could even sow the seeds of the next crisis," he said.

China, which holds much of its $2.85 trillion mountain of reserves in US Treasury bonds, has repeatedly expressed unease about the value of the dollar, while American politicians have complained that Beijing gains an unfair advantage by keeping its own currency cheap.

The idea of SDRs emerged in 1969, to support the Bretton Woods fixed exchange rate system, but when that collapsed a few years later, the role of SDRs was largely forgotten. They allow IMF members the right to swap their own reserves for foreign currencies in times of need.

However, at the London G20 meeting in 2009, in the midst of the credit crunch, world leaders agreed a dramatic $250bn boost to SDRs, sparking speculation that they could play a growing role in the global monetary system.

Strauss-Kahn said the IMF was also examining ways of strengthening international policy co-ordination, and monitoring international imbalances.

Author: Heather Stewart; Source: guardian.co.uk

 
By Admin (from 23/05/2011 @ 11:00:16, in en - Global Observatory, read 2349 times)

A Binghamton University computer scientist with an interest in "green" software development has received recognition for a new approach regarding energy consumption by computer software. 'New' ways of writing code could enable more efficient energy consumption by computers.

Computers and electronic devices, ranging from smartphones to servers, consume a steadily growing amount of energy. In recent years, computer scientists have developed an interest in paring back this consumption, though generally they've approached the challenge through modifying hardware or perhaps operating systems. Liu plans to tackle the problem by considering how programmers can create more energy-efficient software.

"Saving energy is an activity that should come from many layers," said Liu, who plans to build energy-related parameters into a programming language.

A change at that level would permit and encourage programmers to express their energy-saving intentions directly when software is developed.

"Saving energy is often a trade-off," Liu said. "Sometimes you're willing to run your program slower so your cell phone battery can last longer."

For such settings — often specific to the nature of the applications — no automated algorithms know as much as programmers. "Programs today are not just 50 lines of code," Liu said.

They have often grown to be thousands or even millions of lines long. He hopes to employ advanced programming language technologies known as "type systems" to answer questions such as

"What is the energy-consumption pattern of a large program, given the consumption patterns of its fragments?" and "Do programmers have conflicted views of the energy-consumption patterns of their software?"

Energy-efficient solutions at the level of programming languages also enjoy a high degree of platform independence, meaning they can have an impact all along the spectrum from phones to servers.

"In an era when new platforms are introduced every year," Liu explained, "an approach that's platform-independent would be beneficial because it can be applied more broadly."

None of the mainstream computer languages supports energy-aware programming, he said. However, language designers often create a blueprint that can be extended. Java, for instance, could be extended as EnergyJava and remain 90 percent the same. Such moderate changes would make it possible for programmers to adopt it relatively easily.

There isn't much history in this area, Liu said, so it's hard to say how quickly industry will react to the development of an energy-efficient language. However, new language designs have the potential to influence how millions of programmers think.

"I think every researcher wants to make the world better, and we just put it into our own perspective," he said. "Sometime in the Computer future, every Science 101 class may include a lecture or two on energy-aware programming. As an educator, I'm excited about helping to ensure that next-generation programmers are green-conscious from the beginning of their careers."

Source: physorg

Provided by Binghamton University

 

How does an archivist understand the relationship among billions of documents or search for a single record in a sea of data? With the proliferation of digital records, the task of the archivist has grown more complex. This problem is especially acute for the National Archives and Records Administration (NARA), the government agency responsible for managing and preserving the nation's historical records.

At the end of President George W. Bush's administration in 2009, NARA received roughly 35 times the amount of data as previously received from the administration of President Bill Clinton, which itself was many times that of the previous administration. With the federal government increasingly using social media, cloud computing and other technologies to contribute to open government, this trend is not likely to decline. By 2014, NARA is expecting to accumulate more than 35 petabytes (quadrillions of bytes) of data in the form of electronic records.

"The National Archives is a unique national institution that responds to requirements for preservation, access and the continued use of government records," said Robert Chadduck, acting director for the National Archives Center for Advanced Systems and Technologies.

To find innovative and scalable solutions to large-scale electronic records collections, Chadduck turned to the Texas Advanced Computing Center (TACC), a National Science Foundation- (NSF) funded center for advanced computing research, to draw on the expertise of TACC's digital archivist, Maria Esteva, and data analysis expert, Weijia Xu.

"For the government and the nation to effectively respond to all of the requirements that are associated with very large digital record collections, some candidate approaches and tools are needed, which are embodied in the class of cyberinfrastructure that is currently under development at TACC," Chadduck said.

After consulting with NARA about its needs, members of TACC's Data and Information Analysis group developed a multi-pronged approach that combines different data analysis methods into a visualization framework. The visualizations act as a bridge between the archivist and the data by interactively rendering information as shapes and colors to facilitate an understanding of the archive's structure and content.

Archivists spend a significant amount of time determining the organization, contents and characteristics of collections so they can describe them for public access purposes. "This process involves a set of standard practices and years of experience from the archivist side," said Xu. "To accomplish this task in large-scale digital collections, we are developing technologies that combine computing power with domain expertise."

This snapshot corresponds to a regularly organized website containing a total of 2,000 files of different file formats. Highlighted in shades of yellow are different number of Portable Document Format (PDF) files. The purple color shows patterns in file naming convention across directories. Credit: Visualizations courtesy of Maria Esteva, Weijia Xu, Suyog Dutt Jain, and Varun Jain.

Knowing that human visual perception is a powerful information processing system, TACC researchers expanded on methods that take advantage of this innate skill. In particular, they adapted the well-known treemap visualization, which is traditionally used to represent file structures, to render additional information dimensions, such as technical metadata, file format correlations and preservation risk-levels. This information is determined by data driven analysis methods on the visualization's back-end. The renderings are tailored to suit the archivist's need to compare and contrast different groups of electronic records on the fly. In this way, the archivist can assess, validate or question the results and run other analyses.

One of the back-end analysis methods developed by the team combines string alignment algorithms with Natural Language Processing methods, two techniques drawn from biology. Applied to directory labels and file naming conventions, the method helps archivists infer whether a group of records is organized by similar names, by date, by geographical location, in sequential order, or by a combination of any of those categories.

Another analysis method under development computes paragraph-to-paragraph similarity and uses clustering methods to automatically discover "stories" from large collections of email messages. These stories, made by messages that refer to the same activity or transaction, may then become the points of access to large collections that cannot be explored manually.

To analyze terabyte-level data, the researchers distribute data and computational tasks across multiple computing nodes on TACC's high performance computing resource, Longhorn, a data analysis and visualization cluster funded by NSF. This accelerates computing tasks that would otherwise take a much longer time on standard workstations.

"TACC's nationally recognized, HPC supercomputers constitute wonderful national investments," said Chadduck. "The understanding of how such systems can be effective is at the core of our collaboration with TACC."

The question remains as to whether archivists and the public will adapt to the abstract data representations proposed by TACC.

"A fundamental aspect of our research involves determining if the representation and the data abstractions are meaningful to archivists conducting analysis, if they allow them to have a clear and thorough understanding of the collection," said Esteva.

Throughout the research process, the TACC team has sought feedback from archivists and information specialists on the University of Texas at Austin campus, and in the Austin community.

"The research addresses many of the problems associated with comprehending the preservation complexities of large and varied digital collections," said Jennifer Lee, a librarian at the University of Texas at Austin. "The ability to assess varied characteristics and to compare selected file attributes across a vast collection is a breakthrough."

The NARA/TACC project was highlighted by the White House in its report to Congress as a national priority for the federal 2011 technology budget. The researchers presented their findings at the 6th International Digital Curation Conference, and at the 2010 Joint Conference on Digital Libraries.

As data collections grow bigger, new ways to display and interact with the data are necessary. Currently, TACC is building a transformable multi-touch display to enhance interactivity and the collaborative aspects of archival analysis. The new system will enable multiple users to explore data concurrently while discussing its meaning.

"What constitutes research today at TACC will eventually be integrated into the cyberinfrastructure of the country, at which point it will become commonplace," said Chadduck. "In that way, TACC is providing what I believe is a window on the archives of the future."

Source: PhysOrg

Provided by National Science Foundation

 

Data collected by the BaBar experiment during its final months of operation in 2008 point to a new member of the "bottomonium" family of subatomic particles. BaBar collaboration member and SLAC physicist Valentina Santoro presented the results on behalf of the collaboration last month at the Lake Louise Winter Institute, a yearly conference held at Lake Louise, Alberta, Canada. The discovery adds another piece to physicists' model of the so-called "strong" force, which binds subatomic particles into larger chunks of matter.

In 2008, members of the BaBar collaboration announced they'd discovered the lowest-energy bottomonium particle, called ?b (pronounced eta-sub-b). A subsequent BaBar study confirmed the finding in 2009. Continued examination of the final BaBar data set has now revealed another particle of the bottomonium family, called the hb (h-sub-b).

Several variants of bottomonium—a bottom quark bound to a bottom anti-quark—have been predicted and a number have now been observed, the first more than thirty years ago. But many of the predicted states remain unobserved. Each one discovered offers a valuable window into quantum chromodynamics, or QCD, explained BaBar Physics Analysis Coordinator Steve Robertson. QCD is the theory of the strong force that binds quarks into the protons and neutrons that make up atomic nuclei (and ultimately us). It's an important part of the Standard Model, currently the best theory physicists have to explain matter, energy, and how the two interact.

"Since [bottomonium particles] are held together by the strong force interactions, studying the particles is a good way to study the strong force," Robertson explained. However, studying them isn't easy. The strong force, though effectively limited in distance to lengths that span an atomic nucleus, is strong. Individual quarks have never been isolated, and all bottomonium particles are unstable and decay rapidly into lighter, less exotic particles. That means particle physicists must study them indirectly, by taking the final products of a particle collision, after any bottomonia have decayed away, and tracing back along the processes required to create these decay products. In this way, they can determine the nature of the particle at the beginning of that chain of particle decays. It's somewhat akin to running a film backward to watch shards of porcelain on the kitchen floor rise into the air and reassemble themselves into a tea cup on a table.

The BaBar researchers combed through data from more than 120 million electron–positron collisions to find their shards. They also narrowed the possibilities for how the hb particle is created, and confirmed theoretical predictions of its mass.

Less than two weeks after Santoro presented the results, a group of researchers from Belle, a collaboration based at the KEK facility in Japan, announced their observation of the hb particle while studying a completely different and somewhat unexpected decay process. Figuratively speaking, the Belle researchers watched the same pile of porcelain shards reassemble into a coffee mug.

Source: PhysOrg

Provided by SLAC National Accelerator Laboratory

 
By Admin (from 16/05/2011 @ 14:00:25, in en - Global Observatory, read 2068 times)

The key to using silicon in electronic devices such as transistors and solar cells lies in doping, or adding in small quantities of other elements, to create an excess of electrons (n-type) or positively charged holes (p-type) that change the material's conductivity. N-type and p-type silicon are butted together to form p-n junctions, the basic building blocks of electronic devices such as solar cells, light-emitting diodes, and transistors.

For years, researchers have tried to do something similar with quantum dots, tiny semiconductor crystals a few nanometers in diameter. Now, a team of Israeli researchers has reported success. They have doped indium arsenide quantum dots to create n-type and p-type materials. The advance, published in the journal Science, could lead to new types of efficient, cheap, and printable thin-film solar cells.

Quantum dots hold promise for low-cost solar cells because they can be made using simple, inexpensive chemical reactions. Scientists have calculated that quantum dots could be used to make thin-film photovoltaics that are at least as efficient as conventional silicon cells, and possibly more efficient. The higher possible efficiency is because nanocrystals made of certain semiconductors can emit more than one electron for every photon absorbed. Plus, tweaking their size and shape changes the colors of light they absorb.  "We could tune the nanocrystal absorption to match the solar spectrum," says Uri Banin, a professor of chemistry at the Hebrew University of Jerusalem who led the new work.

Despite these advantages, no one has succeeded in making efficient quantum-dot solar cells. For that, you need n-type and p-type nanocrystals, says Eran Rabani, a chemistry professor at Tel Aviv University who was involved in the new work. In solar cells, the electrons and holes that are created when photons are absorbed have to be separated so that the electrons can travel out of the semiconductor to the external electric circuit. Some electrons and holes inevitably combine, but they combine much faster in quantum dots than in large silicon crystals. Doping semiconductor nanocrystals would provide a way for creating p-n junctions that separate electrons and holes efficiently, Rabani says.

Silicon is typically doped with phosphorus or boron atoms, but these materials do not work with quantum dots because the dots are so small. A 4-nanometer-wide nanocrystal contains about 1,000 atoms. Adding a few dopant atoms .can lead to their being expelled from the nanocrystals.

Some quantum-dot doping efforts have succeeded. Researchers have, for instance, doped them with magnetic manganese ions, but this technique does not introduce excess electrons or holes. Others have been able to make undoped nanocrystals n-type by injecting electrons into them. Still others have been able to dope thin films of nanocrystals.

The Israeli team, by contrast, is able to dope freestanding nanoparticles. "This is a major breakthrough here," says Y. Charles Cao, a chemistry professor at the University of Florida in Gainesville. "The major advantage here is you [have] the building blocks for the bottom-up assembly of nanocrystal electronic devices." Another plus, adds Cao, is that the method used to make the dots is easy and inexpensive and could be scaled up to make devices in large quantities.

Source: Technology Review

 
By Admin (from 14/05/2011 @ 11:00:30, in en - Global Observatory, read 3779 times)

Although the lungless salamander and some frog species have developed ballistic tongues, the chameleon's ballistic tongue is the fastest, the longest, and the one that can catch the heaviest prey. A chameleon’s tongue can elongate more than six times its rest length, zipping forward at speeds of 3.5-10.5 meters/second – faster than a human eye can follow. The tongue is called ballistic because, like all ballistic objects, it moves freely without any applied force during its forward motion. Once the chameleon's accordion-like tongue is ejected, it continues moving forward under its own inertia.

With the aim to mimic the mechanisms and performance of the chameleon’s tongue, researcher Alexis Debray of Canon, Inc., in Tokyo, Japan, has developed four ballistic robotic manipulators. Each of the four manipulators excels at copying a certain part of the chameleon’s tongue, and insights from each design could eventually be combined to create a more advanced chameleon tongue that could have manufacturing applications. Debray’s study is published in a recent issue of Bioinspiration & Biomimetics.

“As far as I know, this is the first published demonstration of manipulators based on the chameleon tongue,” Debray told PhysOrg.com. “The particular mechanism of the tongue of the chameleon allows for fast accelerations and velocities and also applies no force during most of the motion.

As Debray explains, what we normally think of as the tongue of the chameleon is actually a larger system called the hyolingual apparatus. The tongue is just a small component on the front tip of the hyolingual apparatus. The majority of the hyolingual apparatus consists of the long, thin hyoglossus complex, which is the part that folds up like an accordion inside the chameleon’s mouth.

The rapid movement of the chameleon’s hyolingual apparatus involves three phases: projection, catching, and retraction. Each of these three phases is controlled by a different system. The tongue (tip of the hyolingual apparatus) contains the accelerator muscle and collagens that control the projection. When the chameleon is ready to project, it slowly protrudes its tongue out of its mouth. Then, the tongue’s accelerator muscle projects the tongue off a bone inside the chameleon’s mouth. No applied force is needed to keep the tongue – and the rest of the hyolingual apparatus – moving forward. When the tongue reaches its prey, a tongue pad containing a small suction on the tip of the tongue can stick to the prey. Finally, the hyoglossus muscle in the accordion-like hyoglossus complex retracts the tongue at a constant velocity. Although the three phases are controlled by different systems, they occur in a single smooth, continuous motion.

Like the chameleon tongue, Debray’s robotic manipulators use different specialized systems for projection, catching, and retraction. To project, all four manipulators use a coilgun in place of the chameleon tongue’s accelerator muscle. Elastomers and/or cotton string is used in place of the chameleon’s hyolingual apparatus. Instead of folding up like an accordion, the elastomers and string are wound around a reel. As for catching, the robotic manipulators use magnets on the tip of the elastomers, which attract magnetic “prey.” For retraction, the manipulators use either an elastomer, a DC motor connected to a reel and string, or a combination of both. One of the manipulators also had wings on the mobile part, which could allow researchers to take advantage of aerodynamic effects.

“In the future, movable wings will allow controlling the trajectory after the ejection of the tongue, which is not possible now,” Debray said. “In our experiments, the wings are not movable. However, their aerodynamic effect on the trajectory of the tongue has been demonstrated experimentally. So far, aerodynamic effects have been poorly studied in the field of manipulators.”

Using a high-speed camera, Debray could track the manipulators in motion. The results showed that the robotic manipulators could reach a projection velocity of 3.8 meters/second without the need for a continuously applied force, which is similar to the velocity of the chameleon tongue. In addition, the robotic manipulators could reach an acceleration of 919 meters/second2, which exceeds that of the chameleon (374 meters/second2). The manipulators that used a DC motor and string for retraction had the same extension ability as the chameleon tongue, and could also adapt to variations in the targets’ distances, as chameleons can.

By incorporating various end effectors onto the robotic manipulators, the devices could have a variety of applications, especially for products passing on a factory line. For example, manipulators with sensors could be used to sense data on products. Stamps and catching devices could be used to deposit patterns and manipulate objects, respectively. Using a mechanism based on the chameleon’s ballistic tongue could provide certain advantages compared with other manipulators due to the small size and flexibility. Further, because ballistic manipulators do not apply a continuous force during their forward motion, an accidental collision would be less severe and likely cause less damage compared to a device being pushed forward. As Debray explained, the current manipulators lack reliability, and so they cannot yet be put to practical use.

“The work presented in the paper is a first step towards manipulators inspired by the chameleon tongue,” Debray said. “Further development is needed in order to use them in factory lines. However, the ultimate goal of this work is the manufacture of Canon products such as cameras and printers, among others.”

Source: PhysOrg

More information: Alexis Debray. “Manipulators inspired by the tongue of the chameleon.” Bioinsp. Biomim. 6 (2011) 026002 (15pp). DOI:10.1088/1748-3182/6/2/026002

 

Economic theory assumes resource scarcity as an important premise, and there is a general consensus that scarce resources are best allocated by means of a market. However, a new doctoral thesis from the University of Gothenburg, Sweden, shows that there may be alternative solutions to the allocation problem.

Economic theory generally assumes that there will never be enough food, water, cars, money etc. to satisfy people's wants. This means that inequalities, conflict and poverty are inevitable parts of society. Many economists feel that scarcity is best dealt with through the presence of a market – the highest bidders gain access to a society's scarce resources.

Yet, economic sociologists do not necessarily see resource scarcity as inevitable, and neither do they always agree with the mainstream solution to the economic problem. There are indeed enough resources, they might argue, but people are for various reasons denied access. For example, there is enough food in the world, but people are still starving. Why is that?

'The market as an allocation mechanism has not been able to distribute food to everyone – every sixth person in the world does not have access to enough food,' says Adel Daoud, author of the thesis.

So, do we need the market?

'Maybe we do, given the present economic system, but we should at the same time ask ourselves whether any alternative allocation models could help us manage the world's resources better, not least considering the climate threat. A so-called economic democracy could be one such solution. In an economic democracy, citizens get to have a say about what and how much of various products and services should be produced,' says Daoud.

One of the main contributions of the thesis is to show the importance of using alternative perspectives, such as economic sociology, to deal with the notion of resource scarcity rather than simply seeing scarcity as inevitable.

Source: EurekAlert

 
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