What can we use instead of gasoline in cars?

politics, science, tech in changing society, technology / /

From Popular Mechanics‘ “How far can you drive on a bushel of corn?“:

It is East Kansas Agri-Energy’s ethanol facility, one of 100 or so such heartland garrisons in America’s slowly gathering battle to reduce its dependence on fossil fuels. The plant processes about 13 million bushels of corn to produce approximately 36 million gal. of ethanol a year. “That’s enough high-quality motor fuel to replace 55,000 barrels of imported petroleum,” the plant’s manager, Derek Peine, says. …

It takes five barrels of crude oil to produce enough gasoline (nearly 97 gal.) to power a Honda Civic from New York to California. …

Ethanol/E85

E85 is a blend of 85 percent ethanol and 15 percent gasoline. … A gallon of E85 has an energy content of about 80,000 BTU, compared to gasoline’s 124,800 BTU. So about 1.56 gal. of E85 takes you as far as 1 gal. of gas.

Case For: Ethanol is an excellent, clean-burning fuel, potentially providing more horsepower than gasoline. In fact, ethanol has a higher octane rating (over 100) and burns cooler than gasoline. However, pure alcohol isn’t volatile enough to get an engine started on cold days, hence E85. …

Cynics claim that it takes more energy to grow corn and distill it into alcohol than you can get out of the alcohol. However, according to the DOE, the growing, fermenting and distillation chain actually results in a surplus of energy that ranges from 34 to 66 percent. Moreover, the carbon dioxide (CO2) that an engine produces started out as atmospheric CO2 that the cornstalk captured during growth, making ethanol greenhouse gas neutral. Recent DOE studies note that using ethanol in blends lowers carbon monoxide (CO) and CO2 emissions substantially. In 2005, burning such blends had the same effect on greenhouse gas emissions as removing 1 million cars from American roads. …

One acre of corn can produce 300 gal. of ethanol per growing season. So, in order to replace that 200 billion gal. of petroleum products, American farmers would need to dedicate 675 million acres, or 71 percent of the nation’s 938 million acres of farmland, to growing feedstock. Clearly, ethanol alone won’t kick our fossil fuel dependence–unless we want to replace our oil imports with food imports. …

Biodiesel

Fuels for diesel engines made from sources other than petroleum are known as biodiesel. Among the common sources are vegetable oils, rendered chicken fat and used fry oil. …

Case For: Modern diesel engines can run on 100 percent biodiesel with little degradation in performance compared to petrodiesel because the BTU content of both fuels is similar–120,000 to 130,000 BTU per gallon. In addition, biodiesel burns cleaner than petrodiesel, with reduced emissions. Unlike petrodiesel, biodiesel molecules are oxygen-bearing, and partially support their own combustion.

According to the DOE, pure biodiesel reduces CO emissions by more than 75 percent over petroleum diesel. A blend of 20 percent biodiesel and 80 percent petrodiesel, sold as B20, reduces CO2 emissions by around 15 percent.

Case Against: Pure biodiesel, B100, costs about $3.50–roughly a dollar more per gallon than petrodiesel. And, in low temperatures, higher-concentration blends–B30, B100–turn into waxy solids and do not flow. Special additives or fuel warmers are needed to prevent fuel waxing. …

Electricity

Case For: Vehicles that operate only on electricity require no warmup, run almost silently and have excellent performance up to the limit of their range. Also, electric cars are cheap to “refuel.” At the average price of 10 cents per kwh, it costs around 2 cents per mile. …

A strong appeal of the electric car–and of a hybrid when it’s running on electricity–is that it produces no tailpipe emissions. Even when emissions created by power plants are factored in, electric vehicles emit less than 10 percent of the pollution of an internal-combustion car.

Case Against: Pure electric cars still have limited range, typically no more than 100 to 120 miles. In addition, electrics suffer from slow charging, which, in effect, reduces their usability….

And then there’s the environmental cost. Only 2.3 percent of the nation’s electricity comes from renewable resources; about half is generated in coal-burning plants.

Hydrogen

Hydrogen is the most abundant element on Earth, forming part of many chemical compounds. Pure hydrogen can be made by electrolysis–passing electricity through water. This liberates the oxygen, which can be used for many industrial purposes. Most hydrogen currently is made from petroleum.

Case For: Though hydrogen can fuel a modified internal-combustion engine, most see hydrogen as a way to power fuel cells to move cars electrically. The only byproduct of a hydrogen fuel cell is water.

Case Against: … And, despite the chemical simplicity of electrolysis, producing hydrogen is expensive and energy consuming. It takes about 17 kwh of electricity, which costs about $1.70, to make just 100 cu. ft. of hydrogen. That amount would power a fuel cell vehicle for about 20 miles.

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Recover sounds from the ancient world

cool stuff, history, technology / /

From Christer Hamp’s “Archaeoacoustics“:

By archaeoacoustics I mean the recovery of sounds from the time before the invention of recording. This implies that such sounds would have been recorded inadvertently, while intending to do sometring else. Not much has been written about this subject and only very few experiments have been made, but I find the subject fascinating enough to dare the deep waters of the unproven and often scorned.

So far no ancient sound has been heard, and the experiments conducted have been attempts to reproduce the conditions at which such recordings would have been produced, successful attempts, according to the papers published.

What is probably the first publication on the subject appeared in 1969, when Richard G. Woodbridge, III related four experiments in a letter in the Proceedings of the IEEE1. In the first experiment, he could pick up the noise produced by the potter’s wheel from a pot, using a hand-held crystal cartridge (Astatic Corp. Model 2) with a wooden stylus, connected directly to a set of headphones. The second experiment yielded 60 Hz hum from the motor driving the potter’s wheel. More interesting were the following experiments, with a canvas being painted while exposed to sounds. In the third experiment the canvas was painted with a variety of different paints while exposed to martial music from loudspeakers. Some of the brush strokes had a striated appearance, and “short snatches of the music” could be indentified. For the fourth experiment, the painter spoke the word “blue” during a stroke of the brush, and after a long search the word could be heard again when stroking the canvas with the stylus.

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Flow defined

commonplace book, education / /

From Mihaly Csiksczentmihalyi’s “Flow: The Psychology Of Optimal Experience“:

Pleasure by itself does not bring happiness. We can experience pleasure (e.g. eating, sleeping, sex) without an investment of psychic energy. Enjoyment on the other hand, happens only as a result of an unusual amount of attention. Pleasure is fleeting and, unlike enjoyment, does not bring complexity (growth) to the self. If one only invests energy in new directions solely for extrinsic rewards, one may end up no longer enjoying life, and pleasures become the only source of positive experience. Without enjoyment life can be endured and can even be pleasant. But it can be so only precariously, depending on luck and the cooperation of the external environment.

Eight Components of Enjoyment

1. Confronting tasks that we have a chance of completing.
2. Concentration.
3. Concentration is possible because the task has clear goals.
4. Task provides immediate feedback.
5. A deep, effortless involvement removes from awareness the worries and frustrations of everyday life.
6. Enjoyable experiences allow one to exercise a sense of control over one’s actions.
7. Concern for self disappears, yet paradoxically the sense of self emerges stronger after the flow experience is over.
8. Sense of time is altered – hours pass by in minutes.

When experience is intrinsically rewarding, one’s life is justified in the present, instead of one being held hostage to a hypothetical future, but we must constantly re-evaluate what we do, lest habits and past ‘wisdom’ blind us to new possibilities. The flow experience – like anything else – is not “good” in an absolute sense, but only in that it has the potential to make life richer, more intense and meaningful. One must distinguish between useful and harmful forms of flow, making the most of the former and limiting the latter.

Commencement of learning something is a flow situation – everything is new and flow absorption is present as one struggles to master the skill. As one progresses, either boredom will ensue because there is no more challenge (the skill has been learned at that level) or anxiety occurs because a bigger challenge than we can cope with presents itself. Either way, one wants to get back to flow, either by overcoming the anxiety challenge by becoming more skilled, or taking on a challenge that will overcome the boredom, thus getting back into flow at a more complex level.

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Why are some people really good at some things?

commonplace book, science / /

From Stephen J. Dubner & Steven D. Levitt’s “A Star Is Made” (The New York Times):

Anders Ericsson, a 58-year-old psychology professor at Florida State University, … is the ringleader of what might be called the Expert Performance Movement, a loose coalition of scholars trying to answer an important and seemingly primordial question: When someone is very good at a given thing, what is it that actually makes him good? …

In other words, whatever innate differences two people may exhibit in their abilities to memorize, those differences are swamped by how well each person “encodes” the information. And the best way to learn how to encode information meaningfully, Ericsson determined, was a process known as deliberate practice.

Deliberate practice entails more than simply repeating a task – playing a C-minor scale 100 times, for instance, or hitting tennis serves until your shoulder pops out of its socket. Rather, it involves setting specific goals, obtaining immediate feedback and concentrating as much on technique as on outcome. …

Their work, compiled in the “Cambridge Handbook of Expertise and Expert Performance,” a 900-page academic book that will be published next month, makes a rather startling assertion: the trait we commonly call talent is highly overrated. Or, put another way, expert performers – whether in memory or surgery, ballet or computer programming – are nearly always made, not born. And yes, practice does make perfect. …

Ericsson’s research suggests a third cliché as well: when it comes to choosing a life path, you should do what you love – because if you don’t love it, you are unlikely to work hard enough to get very good. Most people naturally don’t like to do things they aren’t “good” at. So they often give up, telling themselves they simply don’t possess the talent for math or skiing or the violin. But what they really lack is the desire to be good and to undertake the deliberate practice that would make them better. …

Ericsson has noted that most doctors actually perform worse the longer they are out of medical school. Surgeons, however, are an exception. That’s because they are constantly exposed to two key elements of deliberate practice: immediate feedback and specific goal-setting.

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Word of the day: pareidolia

language & literature, word of the day / /

Pareidolia (from Greek para– amiss, faulty, wrong + eidolon, diminutive of eidos appearance, form) is a psychological phenomenon involving a vague and random stimulus (usually an image) being mistakenly perceived as recognizable. Common examples include images of animals or faces in clouds, seeing the man in the moon, and hearing messages on records played in reverse.

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Malware focused on theft above all

law, security, tech in changing society, technology / /

From AFP’s “70 percent of malicious software aimed at theft: survey“:

Seventy percent of malicious software being circulated is linked to various types of cybercrime, a study by security firms Panda Software showed. …

The survey confirms a shift from several years ago, when malicious software was often aimed at garnering attention or exposing security flaws.

“Malware has become a took for generating financial returns,” the report said. …

About 40 percent of the problems detected by Panda was spyware, a type of malicious code designed for financial gain, primarily through collecting data on users’ Internet activities.

Another 17 percent was trojans, including “banker trojans” that steal confidential data related to bank services, others that download malicious applications onto systems.

Eight percent of the problems detected were “dialers,” malicious code that dials up premium-rate numbers without users’ knowledge; “bots,” a scheme involving the sale or rental of networks of infected computers, accounted for four percent of the total.

The e-mail worm, which was recently considered a major Internet threat, made up only four percent of the total.

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Clay Shirky on why the Semantic Web will fail

language & literature, tech in changing society, technology / /

From Clay Shirky’s “The Semantic Web, Syllogism, and Worldview“:

What is the Semantic Web good for?

The simple answer is this: The Semantic Web is a machine for creating syllogisms. A syllogism is a form of logic, first described by Aristotle, where “…certain things being stated, something other than what is stated follows of necessity from their being so.” [Organon]

The canonical syllogism is:

Humans are mortal
Greeks are human
Therefore, Greeks are mortal

with the third statement derived from the previous two.

The Semantic Web is made up of assertions, e.g. “The creator of shirky.com is Clay Shirky.” Given the two statements

– Clay Shirky is the creator of shirky.com
– The creator of shirky.com lives in Brooklyn

you can conclude that I live in Brooklyn, something you couldn’t know from either statement on its own. From there, other expressions that include Clay Shirky, shirky.com, or Brooklyn can be further coupled.

The Semantic Web specifies ways of exposing these kinds of assertions on the Web, so that third parties can combine them to discover things that are true but not specified directly. This is the promise of the Semantic Web — it will improve all the areas of your life where you currently use syllogisms.

Which is to say, almost nowhere. …

Despite their appealing simplicity, syllogisms don’t work well in the real world, because most of the data we use is not amenable to such effortless recombination. As a result, the Semantic Web will not be very useful either. …

In the real world, we are usually operating with partial, inconclusive or context-sensitive information. When we have to make a decision based on this information, we guess, extrapolate, intuit, we do what we did last time, we do what we think our friends would do or what Jesus or Joan Jett would have done, we do all of those things and more, but we almost never use actual deductive logic. …

Syllogisms sound stilted in part because they traffic in absurd absolutes. …

There is a list of technologies that are actually political philosophy masquerading as code, a list that includes Xanadu, Freenet, and now the Semantic Web. The Semantic Web’s philosophical argument — the world should make more sense than it does — is hard to argue with. The Semantic Web, with its neat ontologies and its syllogistic logic, is a nice vision. However, like many visions that project future benefits but ignore present costs, it requires too much coordination and too much energy to effect in the real world, where deductive logic is less effective and shared worldview is harder to create than we often want to admit.

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The structure & meaning of the URL as key to the Web’s success

commonplace book, tech in changing society, technology / /

From Clay Shirky’s “The Semantic Web, Syllogism, and Worldview“:

The systems that have succeeded at scale have made simple implementation the core virtue, up the stack from Ethernet over Token Ring to the web over gopher and WAIS. The most widely adopted digital descriptor in history, the URL, regards semantics as a side conversation between consenting adults, and makes no requirements in this regard whatsoever: sports.yahoo.com/nfl/ is a valid URL, but so is 12.0.0.1/ftrjjk.ppq. The fact that a URL itself doesn’t have to mean anything is essential — the Web succeeded in part because it does not try to make any assertions about the meaning of the documents it contained, only about their location.

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The 1st software patent

business, history, law, tech in changing society, technology / /

From Robert X. Cringely’s “Patently Absurd: Why Simply Making Spam Illegal Won’t Work“:

Software patents have become inordinately important for something that 25 years ago we didn’t even believe could exist. After several software patent cases had gone unsuccessfully as far as the U.S. Supreme Court, the general thinking when I got in this business was that software could not be patented, only copyrighted. Like the words of a book, the individual characters of code could be protected by a copyright, and even the specific commands could be protected, but what couldn’t be protected by a copyright was the literal function performed by the program. There is no way that a copyright could protect the idea of a spreadsheet. Protecting the idea would have required a patent.

Then on May 26, 1981, after seven years of legal struggle, S. Pal Asija, a programmer and patent lawyer, received the first software patent for SwiftAnswer, a data retrieval program that was never heard from again and whose only historical function was to prove that all of the experts were wrong — software could be patented. Asija showed that when the Supreme Court had ruled against previous software patent efforts, it wasn’t saying that software was unpatentable, but that those particular programs weren’t patentable.

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How patents ruined the Wright brothers

history, law, tech in changing society, technology / /

From Robert X. Cringely’s “Patently Absurd: Why Simply Making Spam Illegal Won’t Work“:

Nobody can deny that the Wright brothers were pioneers. Their use of a wind tunnel helped define the science of aerodynamics and had influence far beyond their time. But their secrecy and litigious nature held back the progress of flying, and eventually lost them their technical leadership. The Wrights flew in 1903. They made a small public announcement 100 years ago, then went silent until 1908 as they worked to solidify their patent position. While they continued to fly from pastures around Dayton, Ohio, the brothers generally did so in secret, waiting for patents to be issued.

When the Wrights finally appeared in public again five years later, first in Washington, DC, and later in France, the performance of their aircraft still astounded the world. But that was it. Once the brothers filed a patent infringement suit against rival Glenn Curtiss, their attention was totally turned to litigation and their aeronautical progress stopped. Curtiss and Wright eventually merged and built aircraft into the 1940s, but the creative energy by that time was all from Curtiss. By then, Wilbur had died and Orville was best known as the man who signed every pilot license. Though their patent was upheld, they didn’t in any sense control the industry they had invented.

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OmniPerception = facial recognition + smart card

security, tech in changing society, technology / /

From Technology Review‘s’ “Face Forward“:

To get around these problems, OmniPerception, a spinoff from the University of Surrey in England, has combined its facial-recognition technology with a smart-card system. This could make face recognition more robust and better suited to applications such as passport authentication and building access control, which, if they use biometrics at all, rely mainly on fingerprint verification, says David McIntosh, the company’s CEO. With OmniPerception’s technology, an image of a person’s face is verified against a “facial PIN” carried on the card, eliminating the need to search a central database and making the system less intimidating to privacy-conscious users. …

OmniPerception’s technology creates a PIN about 2,500 digits long from its analysis of the most distinctive features of a person’s face. The number is embedded in a smart card-such as those, say, that grant access to a building-and used to verify that the card belongs to the person presenting it. A user would place his or her card in or near a reader and face a camera, which would take a photo and feed it to the card. The card would then compare the PIN it carried to information it derived from the new photo and either accept or reject the person as the rightful owner of the card. The technology could also be used to ensure passport or driver’s license authenticity and to secure ATM or Internet banking transactions, says McIntosh.

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Face recognition software as an example of “function creep”

security, social software, technology / /

From Technology Review‘s’ “Creepy Functions“:

Consider one example of function creep. The Electoral Commission of Uganda has retained Viisage Technology to implement a face recognition system capable of enrolling 10 million voters in 60 days. The goal is to reduce voter registration fraud. But Woodward notes that the system might also be put to work fingering political opponents of the regime. And Uganda probably isn’t the first country that springs to mind when someone says “due process” or “civil rights.”

From Technology Review‘s’ “Big Brother Logs On“:

Take the fact that the faces of a large portion of the driving population are becoming digitized by motor vehicles agencies and placed into databases, says Steinhardt. It isn’t much of a stretch to extend the system to a Big Brother-like nationwide identification and tracking network. Or consider that the Electoral Commission of Uganda has retained Viisage Technology to implement a “turnkey face recognition system” capable of enrolling 10 million voter registrants within 60 days. By generating a database containing the faceprint of every one of the country’s registered voters-and combining it with algorithms able to scour all 10 million images within six seconds to find a match-the commission hopes to reduce voter registration fraud. But once such a database is compiled, notes John Woodward, a former CIA operations officer who managed spies in several Asian countries and who’s now an analyst with the Rand Corporation, it could be employed for tracking and apprehending known or suspected political foes. Woodward calls that “function creep.”

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Smart World of Warcraft Trojan

security, social software, tech in changing society, technology / /

From Information Week‘s’ “ Trojan Snags World Of Warcraft Passwords To Cash Out Accounts“:

A new password-stealing Trojan targeting players of the popular online game “World of Warcraft” hopes to make money off secondary sales of gamer goods, a security company warned Tuesday.

MicroWorld, an Indian-based anti-virus and security software maker with offices in the U.S., Germany, and Malaysia, said that the PWS.Win32.WOW.x Trojan horse was spreading fast, and attacking World of Warcraft players.

If the attacker managed to hijack a password, he could transfer in-game goods — personal items, including weapons — that the player had accumulated to his own account, then later sell them for real-world cash on “gray market” Web sites. Unlike some rival multiplayer online games, Warcraft’s publisher, Blizzard Entertainment, bans the practice of trading virtual items for real cash.

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3000 ravers, dancing in silence

commonplace book, technology, weird / /

From The Sydney Morning Herald‘s’ “Clubbers to get into the silent groove“:

For those seeking tranquillity at Glastonbury Festival, a dance tent packed with clubbers is not an obvious sanctuary. But this will be the silent disco – 3000 festivalgoers are to be issued with headphones this year so they can turn up the volume without waking the neighbours.

The quietest party in town is a response to the problem of noise pollution at the festival, which has traditionally led the district council to issue a licence on the condition that the festival’s main stages and tents shut down on the stroke of midnight.

This year, the council is to grant a late licence for the new dance area on the condition that thumping beats and pounding basslines are put to bed at 12. But, thanks to Glastonbury technicians, clubbers won’t have to. For one night only, they will be given wireless headphones, so they don’t trip up when dancing to whatever record the DJ plays.

“I like the idea of people dancing in total silence,” said Emily Eavis, one of the festival organisers and daughter of the founder Michael Eavis. “Imagine if you were feeling a bit worse for wear and thought, ‘This would be a nice quiet place to sit down’.
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“You would be completely freaked out to see 3000 people dancing in silence. It’s certainly quirky, but our big push this year is keeping the noise down because that’s what the council is keen on.”

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Projecting a murdered woman’s image on a building

commonplace book, security, tech in changing society, technology / /

From BBC News’ “Police go big with victim picture“:

Murdered Prostitute A 60ft high picture of a murdered prostitute has been projected onto a derelict block of flats in Glasgow.

Detectives hope it will help to turn up clues about the death of Emma Caldwell, whose body was found in woods in South Lanarkshire on 8 May.

The image was displayed for four hours on the multi-storey flats in Cumberland Street, Hutchesontown on Monday night.

Police said the site had been chosen as it was visible across areas frequented by Emma and other prostitutes.

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Gam Ze Yaavor

commonplace book, language & literature / /

“This too will pass” is “Gam Ze Yaavor” in Hebrew, which is represented by the Hebrew letters Gimel, Zayin, Yod (GZY).

From “Israel Folklore Archive 126“:

King Solomon once searched for a cure against depression. He assembled his wise men together. They meditated for a long time and gave him the following advice: Make yourself a ring and have thereon engraved the words “This too will pass.” The King carried out the advice. He had the ring made and wore it constantly. Every time he felt sad and depressed, he looked at the ring, whereon his mood would change and he would feel cheerful.

From “An Address by Abraham Lincoln Before the Wisconsin State Agricultural Society“, 30 September 1859:

It is said an Eastern monarch once charged his wise men to invent him a sentence, to be ever in view, and which should be true and appropriate in all times and situations. They presented him the words: “And this, too, shall pass away.” How much it expresses! How chastening in the hour of pride! How consoling in the depths of affliction!

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What’s a socio-technical system?

commonplace book, social software, tech in changing society, technology / /

From Ulises Ali Mejias’ “A del.icio.us study: Bookmark, Classify and Share: A mini-ethnography of social practices in a distributed classification community“:

A socio-technical system is conformed of hardware, software, physical surroundings, people, procedures, laws and regulations, and data and data structures.

What’s a socio-technical system? Read More »

Thoughts on tagging/folksonomy

social software, tech in changing society, technology / /

From Ulises Ali Mejias’ “A del.icio.us study: Bookmark, Classify and Share: A mini-ethnography of social practices in a distributed classification community“:

This principle of distribution is at work in socio-technical systems that allow users to collaboratively organize a shared set of resources by assigning classifiers, or tags, to each item. The practice is coming to be known as free tagging, open tagging, ethnoclassification, folksonomy, or faceted hierarchy (henceforth referred to in this study as distributed classification) …

One important feature of systems such as these is that they do not impose a rigid taxonomy. Instead, they allow users to assign whatever classifiers they choose. Although this might sound counter-productive to the ultimate goal of organizing content, in practice it seems to work rather well, although it does present some drawbacks. For example, most people will probably classify pictures of cats by using the tag ‘cats.’ But what happens when some individuals use ‘cat’ or ‘feline’ or ‘meowmeow’ …

It seems that while most people might not be motivated to contribute to a pre-established system of classification that may not meet their needs, or to devise new and complex taxonomies of their own, they are quite happy to use distributed systems of classification that are quick and able to accommodate their personal (and ever changing) systems of classification. …

But distributed classification does not accrue benefits only to the individual. It is a very social endeavor in which the community as a whole can benefit. Jon Udell describes some of the individual and social possibilities of this method of classification:

These systems offer lots of ways to visualize and refine the tag space. It’s easy to know whether a tag you’ve used is unique or, conversely, popular. It’s easy to rename a tag across a set of items. It’s easy to perform queries that combine tags. Armed with such powerful tools, people can collectively enrich shared data. (Udell 2004) …

Set this [an imposed taxonomy] against the idea of allowing a user to add tags to any given document in the corpus. Like Del.icio.us, there needn’t be a pre-defined hierarchy or lexicon of terms to use; one can simply lean on the power of ethnoclassification to build that lexicon dynamically. As such, it will dynamically evolve as usages change and shift, even as needs change and shift. (Williams, 2004)

The primary benefit of free tagging is that we know the classification makes sense to users… For a content creator who is uploading information into such a system, being able to freely list subjects, instead of choosing from a pre-approved “pick list,” makes tagging content much easier. This, in turn, makes it more likely that users will take time to classify their contributions. (Merholz, 2004)

Folksonomies work best when a number of users all describe the same piece of information. For instance, on del.icio.us, many people have bookmarked wikipedia (http://del.icio.us/url/bca8b85b54a7e6c01a1bcfaf15be1df5), each with a different set of words to describe it. Among the various tags used, del.icio.us shows that reference, wiki, and encyclopedia are the most popular. (Wikipedia entry for folksonomy, retrieved December 15, 2004 from http://en.wikipedia.org/wiki/Folksonomy)

Of course, this approach is not without its potential problems:

With no one controlling the vocabulary, users develop multiple terms for identical concepts. For example, if you want to find all references to New York City on Del.icio.us, you’ll have to look through “nyc,” “newyork,” and “newyorkcity.” You may also encounter the inverse problem — users employing the same term for disparate concepts. (Merholz, 2004) …

But as Clay Shirky remarks, this solution might diminish some of the benefits that we can derive from folksonomies:

Synonym control is not as wonderful as is often supposed, because synonyms often aren’t. Even closely related terms like movies, films, flicks, and cinema cannot be trivially collapsed into a single word without loss of meaning, and of social context … (Shirky, 2004) …

The choice of tags [in the entire del.icio.us system] follows something resembling the Zipf or power law curve often seen in web-related traffic. Just six tags (python, delicious/del.icio.us, programming, hacks, tools, and web) account for 80% of all the tags chosen, and a long tail of 58 other tags make up the remaining 20%, with most occurring just once or twice … In the del.icio.us community, the rich get richer and the poor stay poor via http://del.icio.us/popular. Links noted by enough users within a short space of time get listed here, and many del.icio.us users use it to keep up with the zeitgeist. (Biddulph, 2004) …

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Bring down the cell network with SMS spam

security, tech in changing society, technology / /

From John Schwartz’s “Text Hackers Could Jam Cellphones, a Paper Says“:

Malicious hackers could take down cellular networks in large cities by inundating their popular text-messaging services with the equivalent of spam, said computer security researchers, who will announce the findings of their research today.

Such an attack is possible, the researchers say, because cellphone companies provide the text-messaging service to their networks in a way that could allow an attacker who jams the message system to disable the voice network as well.

And because the message services are accessible through the Internet, cellular networks are open to the denial-of-service attacks that occur regularly online, in which computers send so many messages or commands to a target that the rogue data blocks other machines from connecting.

By pushing 165 messages a second into the network, said Patrick D. McDaniel, a professor of computer science and engineering at Pennsylvania State University and the lead researcher on the paper, “you can congest all of Manhattan.”

Also see http://www.smsanalysis.org/.

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