Bioseismic studies have previously documented the use of seismic stimuli as a method of communication in arthropods and small mammals. Seismic signals are used to communicate intraspecifically in many capacities such as mate finding, spacing, warning, resource assessing, and in group cohesion. Seismic signals are also used in interspecific mutualism and as a deterrent to predators. Although bioseismics is a significant mode of communication that is well documented for relatively small vertebrates, the potential for seismic communication has been all but ignored in large mammals. In this paper, we describe two modes of producing seismic waves with the potential for long distance transmission: 1) locomotion by animals causing percussion on the ground and 2) acoustic, seismic-evoking sounds that couple with the ground. We present recordings of several mammals, including lions, rhinoceroses, and elephants, showing that they generate similar acoustic and seismic vibrations. These large animals that produce high amplitude vocalizations are the most likely to produce seismic vibrations that propagate long distances. The elephant seems to be the most likely candidate to engage in long distance seismic communication due to its size and its high amplitude, low frequency, relatively monotonic vocalizations that propagate in the ground and have the potential to travel long distances. We review particular anatomical features of the elephant that would facilitate the detection of seismic waves. We also assess low frequency sounds in the environment such as thunder and the likelihood of seismic transmission. In addition, we present the potential role of seismic stimuli in human communication as well as the impact of modern anthropogenic effects on the seismic environment.

In order to understand the governing dynamics of this technology, begin to understand Signal Transduction and Infrasonics and gleen from that. Its all in Nature not in our heads, we must be able to transform from Nature to Physics to technology and back...

Inform and educate to break the bounds of ignorance!

Educate and Inform:

http://libarynth.f0.am/cgi-bin/twiki/view/...FRadioPhenomena

Search: http://www.scicentral.com/

Invention and Discovery: Atomic Bombs and Fission
Last changed April 1997
Leo Szilard and the Invention of the Atomic Bomb
It would be logical to assume that the discovery of fission preceded the invention of the atomic bomb. It would be normal also to expect that no single individual could really claim to be "the inventor", since the possibility sprang naturally from a physical process, and required the efforts of many thousands to bring it into existence. Many descriptions of the origin of atomic bombs can be found that logically and normally say exactly these things.

But they are not correct.

The idea of "invention" does not usually require the physical realization of the invented thing. This fact is clearly recognized by patent law, which does not require a working model in order to award a patent. It is common for inventions to require additional discoveries and developments before the actual thing can be made. In these cases, an invention may fairly have more than one inventor - the originator of the principle idea, and the individual who actually made the first workable model.

In the case of the atomic bomb there is clearly one man who is the originator of the idea. He was also the instigator of the project that led ultimately to the successful construction of the atomic bomb, and was a principal investigator in the early R&D both before and after the founding of the atomic bomb project - making a number of the key discoveries himself. By any normal standard this man is the inventor of the atomic bomb.

This man is Leo Szilard.

On September 12, 1932, within seven months of the discovery of the neutron, and more than six years before the discovery of fission, Leo Szilard conceived of the possibility of a controlled release of atomic power through a multiplying neutron chain reaction, and also realized that if such a reaction could be found, then a bomb could be built using it.

On July 4, 1934 Leo Szilard filed a patent application for the atomic bomb In his application, Szilard described not only the basic concept of using neutron induced chain reactions to create explosions, but also the key concept of the critical mass. The patent was awarded to him - making Leo Szilard the legally recognized inventor of the atomic bomb.

Szilard did not patent this prescient and tremendously important idea for personal gain. His motive was to protect the idea to prevent its harmful use, for he immediately attempted to turn the idea over to the British government for free so that it could be classified and protected under British secrecy laws.

On October 8, 1935 the British War Office rejected Szilard's offer, but a few months later in February 1936 he succeeded in getting the British Admiralty to accept the gift. Szilard's actions in attempting to restrict the availability of the atomic bomb, are also the earliest case of nuclear arms control. Later, when the possibility of a German atomic bomb had been shown to be nonexistent, Szilard campaigned vigorously against the use of the bomb, and went on to help found The Bulletin of Atomic Scientists and The Council for a Livable World.

The Discovery of Fission
With the discovery of the neutron by James Chadwick in February 1932 a scientific gold rush ensued to discover what effects would be produced by bombarding different materials with this new particle. Over the next several years, teams of researchers in several countries (especially one headed by Enrico Fermi in Rome) bombarded every known element with neutrons and recorded scores, even hundreds, of new radioactive isotopes.

On May 10, 1934 Fermi's research group published a report on experiments with neutron bombardment of uranium. This was the first such investigation to be reported on. Several radioactive products are detected, but positive identifications were not made. Interpreting the results of neutron bombardment of uranium became known as the "Uranium Problem" since the large number of different radioactivities produced defied rational explanation. The dominant theory was that a number of transuranic elements never before seen were being produced, but the chemical behavior as well as the nuclear behavior of these substances were unexpected and confusing.

The first statement of the correct resolution of the Uranium Problem was published by German chemist Ida Noddack in September. Her letter in _Zeitshrift fur Angewandte Chemie_ argued that the anomalous radioactivities produced by neutron bombardment of uranium may be due to the atom splitting into smaller pieces. No notice of this suggestion was taken.

Fermi discovered the extremely important principle of neutron behavior called "moderation" on October 22, 1934. Moderation is the phenomenon of enhanced capture of low energy neutrons, as when they are slowed down by repeated collisions with light atoms.

December 1935, Chadwick won the Nobel Prize for discovery of the neutron.

In November-December 1938, the Otto Hahn and Lise Meitner correctly unravel the Uranium Problem. Hahn determines conclusively that one of the mysterious radioactivities is a previously known isotope of barium. Working with Meitner, they develop a theoretical interpretation of this demonstrated fact. On December 21, 1938 Hahn submits a paper to _Naturwissenschaften_ showing conclusive evidence of the production of radioactive barium from neutron irradiated uranium, i.e. evidence of fission.

In the first few weeks of January, word of the discovery traveled quickly in Europe.

January 13, 1939 - Otto Frisch observed fission directly by detecting fission fragments in an ionization chamber. With the assistance of William Arnold, he coins the term "fission".

By mid January Szilard heard about the discovery of fission from Eugene Wigner, and immediately realized that the fission fragments, due to their lower atomic weights, would have excess neutrons which must be shed. The multiplying neutron chain reaction that he had postulated had finally been discovered.

January 26, 1939 - Niels Bohr publicly announces the discovery of fission at an annual theoretical physics conference at George Washington University in Washington, DC. This announcement was the principal revelation of fission in the United States.

January 29, 1939 - Robert Oppenheimer hears about the discovery of fission, within a few minutes he realized that excess neutrons must be emitted, and that it might be possible to build a bomb.

February 5, 1939 - Niels Bohr gained a crucial insight into the principles of fission - that U-235 and U-238 must have different fission properties, that U-238 could be fissioned by fast neutrons but not slow ones, and that U-235 accounted for observed slow fission in uranium.

At this point there were too many uncertainties about fission to see clearly whether or how self-sustaining chain reactions could arise. Key uncertainties were:

The number of neutrons emitted per fission, and
The cross sections for fission and absorption at different energies for the uranium isotopes.
For a chain reaction there would need to be both a sufficient excess of neutrons produced, and the ratio between fission to absorption averaged over the neutron energies present would need to be sufficiently large.

The different properties of U-235 and U-238 were essential to understand in determining the feasibility of an atomic bomb, or of any atomic power at all. The only uranium available for study was the isotope mixture of natural uranium, in which U-235 comprised only 0.71%.

March, 1939 - Fermi and Herbert Anderson determine that there are about two neutrons produced for every one consumed in fission.

June, 1939 - Fermi and Szilard submit a paper to _Physical Review_ describing sub-critical neutron multiplication in a lattice of uranium oxide in water, but it is clear that natural uranium and water cannot make a self-sustaining reaction. This paper is the first experimental evidence of neutron multiplication.

July 3, 1939 - Szilard writes to Fermi describing the idea of using a uranium lattice in carbon (graphite) to create a chain reaction. This is the first proposal of the graphite moderated reactor concept.

August 31, 1939 - Bohr and John A. Wheeler publish a theoretical analysis of fission. This theory implies U-235 is more fissile than U-238, and that the undiscovered element 94-239 is also very fissile. These implications are not immediately recognized.

September 1, 1939 - Germany invades Poland, beginning World War 2.

4G Technology and the near future

4G technology will allow users to transmit and recieve information at incredible speeds in the future. It will allow the internet to be properly accessed via mobile phones due to increased bandwidths.

4G, or fourth generation technology, will increase data transmission rates (up to 200 times faster than 2G at 20Mbit/sec). 3G data rates are currently 2Mbit/sec, which is quite fast compared to 2G's: 9.6Kbit/sec. 4G builds on the 3G standard, although it integrates and unifies the different interfaces i.e. CDMA, EDGE, etc. The introduction of 3G technology provided a huge expansion in mobile capacity and bandwidth, and 4G will do the same for the spectrum of broadband communications.

It is said that 4G technologies will give way to 3-D virtual reality and interactive video/ hologram images. 4G will increase interactions between corroborating technologies, so that the smart card in your telephone will automatically pay for goods at a grocery store or will tell your car to warm up in the morning, because your phone has noted you leaving the house.

4G is expected to provide "better-than-TV" quality images and video-links, although it is likely that forecasts will change as customer demand develops over time. It is expected that new standards of HTML, Java, HTTP, GIF etc., will need to be developed for the use in 4G.

Published online: 17 November 2004; | doi:10.1038/news041115-11


Simple wire picks up terahertz waves


Mark Peplow
'Coat-hanger' probes could boost airport security.





This terahertz imager is being used to probe the internal structure of a tooth.

© SPL

After years of fiddling around with plastic ribbons and exotic fibres, physicists have found that a simple metal wire is all they need to pick up terahertz radiation. The discovery could speed the development of new medical and security imaging.

Terahertz waves, which nestle between microwaves and infrared light in the electromagnetic spectrum, are able to penetrate materials such as plastic and cardboard, which are opaque to other wavelengths. But technology using them has been slow to take off because it is difficult to guide the waves from one place to another.

Now it seems that a humble length of stainless steel wire is enough to carry the waves to a receiver, in the way that a coat-hanger jammed into a portable radio helps it to pick up a signal. Daniel Mittleman and Kanglin Wang at Rice University in Houston, Texas, reveal their waveguide in this week's Nature1.

"I was very surprised how well it worked and how simple it was," says physicist David Citrin at the Georgia Institute of Technology, Atlanta. "There may be people kicking themselves that they didn't think of this."

Lost in translation

Physicists have tried out a range of terahertz waveguides in the past, says Mittleman, but none of them has been particularly good. For example, hollow metal pipes can carry terahertz waves, but they absorb the radiation very quickly, turning it into heat. This means that most of the terahertz waves are lost in translation. Pipes also transmit waves of different frequencies at different speeds, making it impossible to reconstruct detailed information from a broad frequency scan. Mittleman's wire avoids both of these problems.

The latest discovery was a beautiful example of scientific serendipity, says Mittleman. The researchers were working on a new way of producing terahertz images that involved bringing a metal rod very close to a metal surface. When they pointed the terahertz waves at the metal rod, rather than the surface, they found that they could still pick up the radiation, but with a time delay as the wave travelled down the rod.

The new method is comparable to a radio aerial, in which electrons are sloshed from one end to the other as the long wavelength radio waves change the electromagnetic field in the wire. At shorter wavelength terahertz frequencies, the electrons only wobble by a few millimetres, but this creates areas of high and low electron density.

These areas of high and low density then travel down the wire, just like sound waves passing through air. When they hit the end of the wire, they regenerate electromagnetic terahertz waves that cross a short distance through air before being picked up by a receiver. This allows Mittleman and Wang to use wires to guide terahertz waves to wherever they want.

Wired up

To prove the point, Mittleman and Wang made an endoscope that can see inside confined spaces using just two wires and a metal plate. Terahertz waves travel down one wire, bounce off the angled plate and the interior of the container, and then travel back up the second wire. Amplifying this signal generates a crude image of the container's insides.

Once they can be manipulated more easily, terahertz waves could be used to see inside suspect packages at airports, Mittleman says. They will not replace X-rays, because they cannot penetrate metal boxes. But they can distinguish between different chemicals inside a package, each of which absorbs a characteristic set of terahertz frequencies.

A terahertz device similar to Mittleman and Wang's, for example, could be inserted through tiny holes in cargo containers to check for residues of explosives. Because the wire can carry a very broad range of different terahertz frequencies at once, it allows a general chemical analysis.

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References
Wang K., Mittleman D. M., Nature, 432. 376 - 379 (2004). | Article | PubMed |

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Story from news@nature.com:
http://news.nature.com//news/2004/041115/041115-11.html



© 2004 Nature Publishing Group | Privacy policy

ASIA : NTT DoCoMo announced it achieved 1Gbps real-time packet transmission in the downlink at the moving speed of about 20km/h in a field experiment on fourth-generation (4G) radio access. The experiment took place in Yokosuka, Kanagawa Prefecture on May 9, 2005.

This is the latest achievement in DoCoMo's ongoing development of key radio access technology for 4G mobile communications.

The 1Gbps real-time packet transmission was realized through Variable Spreading Factor-Spread Orthogonal Frequency Division Multiplexing (VSF-Spread OFDM) radio access and 4-by-4 Multiple-Input-Multiple-Output (MIMO) multiplexing using "adaptive selection of surviving symbol replica candidate" (ASESS) based on Maximum Likelihood Detection with QR decomposition and the M-algorithm (QRM-MLD), which was developed by DoCoMo. By using the new algorithm, DoCoMo was able to reduce the large computational complexity of the original MLD method while maintaining almost the same achievable throughput performance. Frequency spectrum efficiency, which is expressed as information bits per second per Hertz, is 10 bits per second per Hertz, about 20 times that of 3G radio networks' spectrum efficiency.

During an earlier trial in July 2003, DoCoMo achieved 100Mbps and 20Mbps data rate transmission in the downlink and uplink, respectively, in outdoor environments using the same 100MHz bandwidth.

DoCoMo will continue to conduct field trials as part of its program to develop a 4G global standard in cooperation with the International Telecommunication Union Radiocommunication Sector. The telecommunications council of Japan's Ministry of Internal Affairs and Communications aims to see 4G services commercialized in the country by 2010.

xMaxTM First Long-Range Field Test A Success

New Spectrum Sharing Technology Uses Micro-Power Levels to Deliver Broadband





SARASOTA, FL – xGTM Technology, LLC moved its promising spectrum sharing technology out of the lab and into the field, successfully conducting its first long-range wireless tests of xMax – a novel radio frequency (RF) signaling technique that represents an entirely new approach to the problem of spectrum overcrowding.



Using only a VHF paging channel and negligible power in adjacent sidebands, an xMax transmitter and receiver pair with ground level antennas delivered data to the xMax receiver over a mile away. Ground level testing presents an extraordinary challenge: the signal must travel through buildings and other obstacles without significant loss or distortion -- a feat that more common microwave-based wireless broadband techniques have difficulty achieving.



Transmitting at .0005 Watts, xMax was able to demonstrate range orders of magnitude farther than other broadband technologies such as Wi-Fi. By comparison, typical performance of a Wi-Fi 802.11 hotspot at 1 Watt (or 2,000 times more power than xMax) using ground level antennas is approximately 300ft under similar non-line of sight (NLOS) conditions.



“Demonstrating that broadband wireless communications can occur at such micro-power levels in the presence of interfering signals overturns long-held industry ideas,” said Joe Bobier, President of xG Technology, LLC and inventor of the technology. “What is really exciting, however, is that xMax’s unique signal profile is a perfect fit for low frequency channels that have been previously unsuitable for wireless broadband.”



Later this year, xG will release reference designs for sub-Gigahertz fixed wireless base stations and consumer premise equipment (CPE) based on current working prototypes that could outstrip the capabilities of technologies like WiMAX.



About xMax


Unlike other wireless technologies that move as much power as possible from the carrier into the information-bearing sidebands, xMax does just the opposite, placing more than 99 percent of its power within a narrowband carrier while keeping its sideband energy at micro-power levels. Typically –60dB to –100dB below the carrier, xMax’ unique information-bearing sideband, dubbed xG Flash SignalTM, can be as much as 100,000 times below the FCC’s “Part 15” regulations.

Lower frequencies – located below one Gigahertz on the spectrum – are well known by communications engineers to outperform higher frequencies. The performance shortfall is so stark that it can take 25-50 times more towers to wirelessly cover a given area using Gigahertz frequencies. The problem, however, has been that lower frequencies have been divided into small segments for thousands of disparate uses. This overcrowding of the lower spectrum has left wireless broadband service providers with no other option than to shift to higher frequencies—accepting a hefty price/performance penalty.

xMax is set to change all of that by enabling wireless broadband at sub-Gigahertz frequencies. xMax only requires a narrow segment of unoccupied spectrum in order to place its carrier signal, while its proprietary xG Flash Signal is sent at such unusually low power levels that it can operate far below the point of impacting other systems, essentially allowing it to share spectrum with existing users.



“The success of this test confirms what we’ve always believed,” said Rick Mooers, Executive Chairman of xG Technology. “xMax is likely to be an equation-changer in the wireless and wireline telecom industries.”



xMax is already making waves within the engineering community. Dr. Stuart Schwartz, Princeton University engineering professor and IEEE fellow, has stated: “xG technology can deliver broadband speeds with a remarkably efficient use of the radio spectrum. It is a technology that has the potential for a major impact on the area of wireless communications.”



xG’s FCC counsel, Hal Mordkofsky, believes that xMax may impact communications policy in similarly profound ways. “One of the biggest problems facing the Federal Communications Commission is the increasing shortage of the usable frequency spectrum. The long-term solution may very well be xMax, which makes far more efficient use of the frequency spectrum than has ever been possible.”





####

Pioneering innovation in telecommunications research, xG Technology has developed xMax – a groundbreaking radio frequency (RF) modulation and encoding technology that enables faster, farther, and cheaper communications. xMax takes high-speed communications “beyond broadband” and is suitable for both wireline and wireless networks. Privately held, xG Technology is based in Sarasota, Florida (USA).



www.xgtechnology.com

4G will easily and quickly converge the network towards a homogenous platform and I dream that very soon we'll have distributed Exchange free communication network which will be last G.

Wow, I have imagined this progress! In my mind, I have set what I see as the gold standard for wireless: 1/1 Stands for 1 mile and 1 month.

I think this should be the opening salvo for world wireless: coverage up to one mile from base and a fuel cell that should last for at least a month. This xmax fills the bill for the range and I think that before the fuel cells actually go to production the range for durability will come way up, possibly to a month of use. Now, even in the promos, the time for use is just over what it covers in battery usage, just 8 hours, and that just won't do.

The 4G Report 2005: Changing the wireless value chain
30th June ,2005

"4G" doesn't just define a standard, it describes an environment were radio access methods will be able to interoperate to provide communications sessions that can seamlessly "hand-off" between them. More than any other technology, 4G will have a profound impact on the entire wireless landscape and the total value chain. It is never too early to understand it.

4G is happening now and there is fierce activity in R&D and Intellectual Property Rights (IPR). According to the 4G Mobile Forum, there were only eight organisations involved in 4G R&D in 2000. By 2003, that number had expanded to over 2,500 bodies worldwide. This unique report looks at the main companies, organisations and governments that are playing an active part in 4G's development. Visiongain published the first commercial report on 4G over 4 years ago - Discover how the market has developed and how those changes effect you.

Some of the key questions answered by this report include:

How will 4G affect your wireless value chain?
How should operators, vendors and application providers position themselves in the 4G space?
When will 4G happen, what is the 4G timeline and how will it affect you?
What services and applications will 4G enable?
What are the challenges faced in making 4G a reality?
How much will it cost?
This vital 90+ page report delivers an in-depth look at the current state of development in 4G. It provides you with an outlook for future developments and opportunities, which you need to understand today.

By purchasing this report you will learn about:

The latest technological elements of 4G and how they will interoperate with each other;
Up-to-the-minute analysis of 4G opportunities and how to profit from them;
Who are the most influential companies, organisations and government bodies making 4G happen?
The benefits that 4G will bring to you throughout the value chain.
In this essential visiongain report, "The 4G Report 2005: Changing the wireless value chain", you will discover and understand the complex, profitable New World of 4G communication.

It cannot be too early to begin thinking about and planning for 4G. The industry is moving and changing fast - you cannot afford to be left behind.

All Material Subject to Copyright. All logos, graphics and trademarks are the property of their respective owners.

America always thinks that it is the center of technology influence. But it is not. The 3G snafu is just that. Your phone bill and dead zones prove that. You have multiple companies pitching multiple service and at a price that is robbing you blind each month. Your 3G, and other protocols are just fixes for ignorance in how wireless communications technology is supposed to work. America will always be behind everyone else because you don't think outside the box and you follow this master plan of improvement which in fact is a cover for business to figure how to rip you off technologically and financially in the future. 4G is a system that will allow you the consumer to use communications at its best without the restrictions and pricey rip-offs on phones and service all given to you with quality and exact science. But America loves to be lied to. Just look at the Space Shuttle....just a little switch because someone did not wish to improve on the technology and or quality because of price...WorldCom...and others while you just keep paying your phone bill each month and dream of the future rather than change it. The consumer has the power to change not Verizon or Sprint...you can demand change or change it yourself as we are doing with or without America.
4G technology may seem that it is just an idea, but are you sure of that? I think not. The proof is what you have now every time you make a phone call or use the internet or some other device that was designed in America. America is NOT the center of the technology universe anymore! And 4G will one day prove that statement.

4G technology is a technology that relies on engineers and the like to separate themselves from the patchwork electronics that we are all accustomed to and design a technology infrastructure that maximizes technology and minimizes the cost to we the consumer. We rely on imperfect information to make decisions that always affect our end results. We have thousands of repeaters and lineframe switches that grow like mushrooms on a farm around the USA. And we still have dead zones. We have too many protocols that depend on the other and we all pay for it in the long run. Asia is easiest to test and deploy new technologies because the laws and regulations are more liberal and the people are more in unison because of culture. America is now a third world country as far as technology improvements. Money and greed are its products and we the consumer pay for the "shiny" things they offer us...ringtones....etc. 4G could be deployed in America but its own regulations
and business greed will not allow it so it must be done offshore this time with credit due to the ones that truly step outside the box. Look at your phones and service and tell me that you are happy...2 year contracts, limited access...and promises of future benefit that never happens. Big Telecom companies falling over each other to position themselves for the game of the century!