Saturday, July 29, 2006

 

A paint which partly blocks mobile calls

Discoveries

culture de nanotubesA new paint mixed with nanoparticles may offer the sweet silence that theatre owners, school officials and clergy crave. Once applied to walls, the paint blocks cell phone radio signals, locking out any call. NaturalNano, a firm in Rochester (New-York), commercializes the materials.

Two-way radio-frequency transmissions from cell phones, WiFi, and other electronic devices may be blocked.

Nanotubes coated or loaded with copper may be used in paint applied to walls to passively block specific radio frequency ranges. That makes the difference with current techniques which scramble ALL received signals.
Indeed, the wireless phone industry is opposed to blocking technologies, citing legalities and various emergency calls: police, fire, ER, ...
NaturalNano has the solution: Using a complementary technology licensed from AMBIT Corporation, building managers may selectively override the blocking to allow the use of two-way devices in a room or building. An indoor antenna picks up cell-phone or other signals and sends them to an external antenna through an electronic filter

Source: the newspaper Communications of ACM.
For those who do not know: nanoparticles are a direct application of nanotechnologies. The small tubes on the picture here above are 40 nanometers length, or if you prefer 40 x 10-9 meter, or again 0,000000040 meter. Or 400 atoms. This microscopic size makes it possible to block waves because they're lost after tons of rebounds.

Labels:


Wednesday, July 26, 2006

 

Economic Decreasing

ecology


Last week, La Première, a Belgian public radio station, has proposed a talk show about Economic Decreasing.

The speakers' comments were so interesting that everybody should be challenged by the ecological cause seen under this angle.

To be brief, the decreasing is a concept which affirms that infinite economic growth, i.e. the perpetual increase of an economic indicator, is simply not acceptable by the ecosystem of the Earth.

The decreasing comes from the fact that the planetary resources are not inexhaustible. A simple figure: 80% of the resources are exploited per 20% of the world population. It's almost the end of fossil resources (gas, oil): one speaks about 20 or 30 years. And thus the infinite growth is not possible for the limited Earth.

Serge Latouche, highly skilled professor of economy at the University of Paris-Sud :

The decreasing is a provocative slogan which aims to fight with the set language: for the growth, always more... While we know very well that the growth brings us right in the wall . Thus behind this word, there is the questioning, the change of direction for our growth society [...] This is about finding what the experts call a bearable ecological footprint, i.e. a way of life more frugal (does not mean antiquated) to be compatible with the regeneration of the biosphere.

Space available on the planet is 126 billion acres but useful space, bio-productive, is only 30 billion. And since we're about 6 billion, it makes 4.5 acres available to nourish us, to dress us, for all our consumption and especially (it is often forgotten) to recycle our waste. Because each time we burn 1 liter of gasoline, 50 square feet are necessary to absorb emitted CO2. This space, we exceed it of 30%. Globally, if everyone was European, we would need three planets. And if everyone was Australian or American, we would need six of them. It's still possible for the moment because, contrary to the generally accepted idea, the South countries give us a considerable technical aid since if everyone was from Burkina Faso, a tenth of the planet would be enough.

Vincent Cheynet, founder of "casseurs de pub" and chief of the magazine "La Décroissance":
We approach the peak oil, from the moment we will extract the maximum of oil from the ground. After that, the oil extraction will decline, one imagines 3% per year and today, there is no alternative source of energy which has the same capacity as oil. Thus if we do nothing, quite naturally, the regulation is likely to be done by chaos and will create major socio-economic problems. And that's also an enormous stake of the decrease: vis-a-vis this rarefaction of the natural resources, today we must anticipate this movement. [...]

That's the reason why, for example, we fight for the suppression of the Grand Prix de France de Formule1. Obviously, a Grand Prix like this one does not represent an extraordinary pollution (it is certainly a consequent pollution), but we especially attack the symbol which the Grand Prix de France represents, i.e. a kind of paroxysm of pollution, plundering of natural resources, wasting and we think that we will manage also to transform the society by attacking this type of symbol. This way, we'll make understand people that this insane race to technics, growth and wasting cannot continue eternally.

Alain Gras, professor of sociology in La Sorbonne :
It is only in 1900, therefore hardly more than one century ago, that fossil energy won against renewable energy. Today, we just know the fossil energy as a mean of development. Thus, I think that it would be necessary to try to return to other energy, obviously to renewable energy. And try all of them. And indeed, a new frugality in the use of energy. [...] To modify our behaviour with energy, it's obviously to have less comfort in the everyday life and in particular also to decrease mobility. Because mobility is the large greedy one, it's the big catastrophe on the energy level .

Integral script of the show (in French) (many thanks to the speech recognition)

"
It's now time to understand how much the desire of going quick is insane when we turn around " (Albert Jacquard)

Labels:


Saturday, July 22, 2006

 

The relative success of iTunes

anecdote

On the Paul Lamere's blog (see previous article), one can read an interesting note about iTunes.

Reminder: iTunes is a proprietary digital media player application, launched by Apple Computer in 2001, for playing and organizing digital music and video files. The program is also an interface to manage the music on Apple's popular iPod digital audio player. Additionally, iTunes can connect to the iTunes Music Store (iTMS) which allows users to purchase digital music and movie files that can be played by iPods and iTunes.

The article reminds that Apple sold, during the first quarter of 2006, its 50 millionth iPod. Right around the same time, Apple celebrated selling its 1 billionth song on iTunes, considered as a big commercial success.
But is it really true? If we divide 1 billion by 50 million, we notice that only 20 songs on average were sold, by iPod. Therefore, after having spent $200 or $300 for a luxury walkman, an average person spends $20 to put music iTunes on it.

Lamere concludes: if this user buys 1 song per month, the credit card transaction fees have to be eating up any potential profits.

Labels:


 

Search Inside The Music

exploits

Search Inside The Music is a project of Sun Labs directed by Paul Lamere. The purpose is to skilfully link songs, by methods much more sophisticated than the usual tags genre or artist.

I.e. in a collection of music, it's possible to cross the genres to find 2 titles which have similarities of timbre or “musical energy”.

Concretely, the project explores new methods of music search thanks to the musical contents and the context. It's then a question of helping us to find and organize our music based on properties such as the words, the musical topic, the melody, the tempo, the rate/rhythm and the instrumentation. It is also possible to integrate the musical practices of the user into it.

The first thing to be made, it is to generate metadata directly from audio contents: pitch, harmony, timbre, instrumentation, tempo, rythm patterns, energy level.
That leads to a problem of resources. Sun Labs analyzes the musical properties frame by frame. Each frame is 40 milleseconds of music, which means 5000 frames on average per song, which means plenty of data to be treated.

Multiply that by the number of songs in an even modest collection, and one speaks then about million frame, a colossal calculation. This is a case where being part of Sun really helps. They have a “grid computing”, a wall to which it is enough to be connected to have the resources to thousands of network computers, as well as their storage capacities. According to Lamere, a simple computer would take 6 years to analyze a collection of 2 million songs, while same work on a grid of 1000 computers would take one weekend.


One of the most impressive functionalities of the system is the visualization of the acoustic distances between songs of all genre. The researchers of Sun Labs analyzed nearly 5000 songs, categorized by the genre specified by the artist, and encrusted in a 3D array according to their acoustic similarities.
The system can thus generate a X minutes-playlist, while going from Rage Against The Machine because you are irritated after the job and finishing with a piece of Schumann to arrive calm at the house. The whole with an unperceivable transition and only with tracks you like.

What are the commercial applications?
Beyond the example above, which remains criticable because the music is finally perception, one speaks about musical indexing: to find a solo of trumpet in a long jazz piece. That can also contribute to copyrights. As to help a film maker to find the music which corresponds to a scene. That also can help us to find the title of a song because we remember 3 tones.
Briefly, like often, Sun is right at the beginning of research, and at the beginning of discovery of new real applications.


Source: Sun, one month ago.

For those who do not know:
A metadata
est une donnée servant à définir ou décrire une autre donnée quel que soit son support (papier ou électronique). Dans un organisme documentaire (une médiathèque par exemple) are data that describe other data. Generally, a set of metadata describe a single set of data, called a resource.Metadata are of special interest in various fields of computer science, e. g. information retrieval and the semantic web. Although many consider them a powerful tool to bridge the semantic gap, they are criticized severely by others.

Labels:


Wednesday, July 19, 2006

 

Comparison VoIP calling rates: 12 products

internet


Regularly, we propose a comparison of the calling rates to give a call from your computer to a mobile or landline everywhere in the world.
Well, this is over.

Since the website VoIP products exists, that does not worth anything.
Indeed, the update is weekly and is about 12 products: Skype, Gizmo, Yahoo Messenger, SIP discount, VoIP Buster, VoIP Stunt, InternetCalls.com, poivY, voipcheap, voip discount, WebCall direct, and Free Call.
For about 50 destinations (against the 200 we proposed before - allright here is the previous version).

Some notes:
  • unfortunately, only tariff comparison, no test on quality.
  • This is for United States. A page for Europe exists. On the latter, you have an explanation for each product, even Google Talk that can be used only to talk from PC to PC (or you can use gateway-companies but it is not taken in account here).
  • 7 of those products are sub-products of VoipBuster.com !
  • As always, be attentive to the contract. Some items are rather demanding and can lead to the cancellation of an unused credit.
  • As opposed to what is written, the rates of Windows Live Messenger is different acoording to the place you give the call! And it's almost always most expensive.
  • Calling between 2 computers is always free.
  • The prices are in USD cents per minute including VAT, except those of voipcheap.co.uk which are in English pence per minute. Here is an excellent currency converter website.


Labels:


Friday, July 14, 2006

 

The Galileo Code

navigation


The navigational satellite GIOVE-A, launched recently, is the prototype of 30 satellites that will compose Galileo in 2010. Reminder: Galileo is a positioning system by satellite, the direct competitor of American GPS that everyone uses for the moment.

Because GPS satellites are payed by US taxpayers, the signal is free. Consumers need only purchase a GPS receiver. On another hand, Galileo must make money to reimburse its investors. That's why someone has to pay to get the PRN codes necessary to decode the signal.

And since Galileo and GPS will share frequency bandwidths, Europe and the US signed an agreement whereby some of Galileo's PRN codes must be open source. Nevertheless, after broadcasting its first signals on January 12, 2006, none of GIOVE-A's codes had been made public.

In mid-January, Mark Psiaki, professor of mechanical and aerospace engineering at Cornell and co-leader of Cornell's GPS Laboratory, requested the codes from Martin Unwin at Surrey Satellite Technology. Ltd, one of three privileged groups in the world with the PRN codes. Martin politely declined.
Then Mark contacts his friend Olivier Montenbruck, a German colleague. He realizes that even him wants to know the codes. Even Europeans were being frustrated!

Upset, Mark and his team develop in one week a algorithm to extract the codes. Two weeks later, he got a first result that he has to throw away 'cause the signal's repeat period was twice that expected. But in the middle of March, they end up with their first estimations, with a little tip from Olivier. Finally, on the first of April, they publish it on this website.
Two days later, Canadian-based GPS receiver manufacturer, NovAtel, downloaded the codes from the website and began tracking GIOVE-A for the first time.

Then, Galileo also publishes the PRN codes, mid-April. But they're not the ones used bu GIOVE-A. Furthermore, the same publication labelled the open source codes as Intellectual Property, claiming a licence is required for any commercial receiver.
"Apparently they were trying to make money on the open source code", says Mark.

But, afraid that cracking the code might have been copyright infringement, Psiaki's team consulted with Cornell's university counsel, and were told that while cracking the encryption of creative content like music or a movie, is illegal, cracking a navigation signal is an open game. Vamos!

The conclusion of this story: Europeans cannot copyright the data coming from a satellite that they built! It's quite odd if all the business-plan is based on seling the codes. I don't think so. And moreover, Galileo affirms that the final codes will be different. But now, we know how to do...


Source: Cornell University, last week.


For those who do not know:
- GIOVE-A means
Galileo In-Orbit Validation Element-A.

- Galileo is a joint venture of the European Commission, the European Space Agency and private investors, including an arm of the Chinese government.

- In cryptography, pseudorandom noise (PRN) is a signal similar to noise which satisfies one or more of the standard tests for statistical randomness. Although it seems to lack any definite pattern, pseudorandom noise consists of a deterministic sequence of pulses that will repeat itself after its period. Each pulse in this sequence is known as a chip and the inverse of its period as chip rate. In cryptographic devices, the pseudo-random noise pattern is determined by a key and the repetition period can be very long, even millions of years.

- Open source describes practices in production and development that promote access to the end product's sources. Some consider it as a philosophy, and others consider it as a pragmatic methodology. Before open source became widely adopted, developers and producers used a variety of phrases to describe the concept; the term open source gained popularity with the rise of the Internet and its enabling of diverse production models, communication paths, and interactive communities.

Labels:


 

Incredible Hotels



Last month, 01men published an great article (in French) about amazing hotels.

In a totally subjective order:

Costa Rica, close to the Arenal volcano. Always in activity, this volcano has undergoes a large explosion 4 years ago. The hôtel is located in the zone D, i.e. a small-risk zone: there is a ravine between the hotel and the volcano. But of course, an evacuation plan exists.
Between 60 and 70 euros for a double room.












The guides who answer visitors’ questions at the Old Prison of Trois-Rivières are former inmates.Based on personal accounts and faithful reconstructions, the Musée québécois de culture populaire Go To Jail exhibit gives visitors a very strong, very real and sometimes disturbing experience.
En prison is the name of the hotel. 57 USD to be free after a night.


Chole Mjini is a lodge set in the baobab trees on the island of Chole at the Southern tip of Mafia. A small island off a small island off a small island. You can not get more remote. There are only eight rooms at Chole Mjini and these are perched in the baobab trees, set amongst the ruins of an early settlement from the days when Chole held a trategic position on the trade route between the mainland town of Kilwa and Zanzibar. The rooms are simple and very open to the elements as one would expect from a luxury tree house, but the beds are comfortable and each room has beautiful views. Between 290 and 470 euros for a room.















In another style, the Ice Hotel Quebec-Canada. The snow is used as raw material for the construction of the hotel, it is generated by snow guns. It is then puffed up on metal moulds in the shape of domes. Ten hours at three days later (according to the temperature), these moulds are withdrawn and ready for the forthcoming season. The Ice Hotel’s four foot thick walls act as an excellent insulator and helps maintain a constant temperature, acting similarly to a “Thermos”. The temperatures inside the Ice Hotel remain between 28° to 23° Fahrenheit (-2° to –5° Celsius). For example, on a very cold day, the exterior temperature of the Ice Hotel may be -18° F or –28° C, however, the interior temperature of the Ice Hotel would not descend below 25° F or –4° C.

The Ice Hotel covers an area of 3,000 m2 (30,000 ft2) composing of 500 tons of ice and 15,000 tons of snow.
The bed is made of a solid block of ice with diagrid out of wooden and a mattress. The latter are covered with covers of Hudson Bay and you will sleep in a special bed bag conceived to be warm until a temperature of -30°C.
Prices are from 580 to 700 USD.














The article also describes
- rooms in a headlight of the old Harlingen port in the Netherlands,
- rooms in the Lilla Marras, an old lifeboat,
- Mongolian yurts in Switzerland at 2000m on the top of the Leman lake
- a 2-rooms-hotel in the giant crane of the port of Harlingen...


For those who do not know: A Yurt is a portable felt dwelling structure used traditionally by nomads in the steppes of Central Asia..

Labels:


Thursday, July 13, 2006

 

Brain scan and Decision-making aid

exploits

Researchers of the UCL, the University College of London, have completed a brain-scanning experiment using a functional Magnetic Resonance Imager (fMRI). It's now fashion: remember the hand controlled by the thought.

But this time, the subjects are men and women who must take a decision. The brain locked up in the MRI scan, they are presented with a series of slot machines that paid out different amounts of money: they have to find the best one.

Analyzing the operation of the brain during this stage, the scientists of the Gatsby Computational Neuroscience unit intend to discover what allows us to make a decision, and to adapt this routine into an algorithm.

"If we can understand how people solve problems using past experience, we can design better decision-making machine algorithms that could be used in something like an autonomous robot..."
Nathaniel Daw says. He's the big boss.
But he's cracking up when he adds "or in perfecting systems such as those used by Amazon.com to price books with." Maybe he has a cousin who works for Amazon, we don't know.

Anyway, another lab, the Accenture Technology Lab, develops in parallel a system of camera-monitoring based on this technology. While a computer can treat a lot of data without being able to interpret and make true decisions, a human being can treat only a few data at the same time but more intelligently. The system of Accenture should be able to detect anomalies and to inform a guard if necessary.


Source: Computing, last week.

Labels:




archives >> April - March - February - January -December - November - October - September - August - July - June - May


Powered by Stuff-a-Blog
une page au hasard

This page is powered by Blogger. Isn't yours?