By JOHN MARKOFF
Published: August 31, 2007

SAN FRANCISCO, Aug. 30 — Researchers at I.B.M. laboratories say they have made progress toward storing information and computing at the level of individual atoms.

The scientists documented their work in two papers appearing on Friday in the journal Science. Both papers are focused on new understanding of the behavior of magnetism at the tiny scale of nanotechnology, where scientists hope to develop electronics made from components that are far smaller than today’s transistors and wires.

In one paper the researchers describe a technique for reading and writing digital ones and zeroes onto a handful of atoms, or even individual atoms. The second paper describes the ability to use a single molecule as a switch, replicating the behavior of today’s transistors.

The papers are the latest indication that computing technology is beginning to emerge that could replace today’s microelectronics materials in the next decade.

R. Stanley Williams, a Hewlett-Packard physicist, said this week that his group had begun manufacturing prototypes of a silicon chip that combines both conventional microelectronics and molecular scale components. Their first hybrid device is a circuit called a field programmable gate array, or F.P.G.A., using molecular-scale components as the configuration circuitry, an approach that will save tremendous space in the chip design.

A team of I.B.M. researchers at the company’s Almaden Research Center in San Jose, Calif., were able to use a scanning tunneling microscope to observe the magnetic orientation of iron and manganese atoms at low temperatures. Controlling magnetic direction is a crucial technique that is used in reading and writing digital information on magnetic storage disks like standard hard drives.

In addition to the potential storage applications, the researchers noted that atomic-scale magnetic structures are also of scientific interest because they may be harnessed for quantum computing, a technology that would be far faster than current computers for some specialized uses.

A second group of I.B.M. scientists in Zurich were able to place two hydrogen atoms in an ultrathin insulating film and switch them back and forth between two states, creating the equivalent of the ones and zeroes used in standard chips. They were also able to use the same switching process to inject an electric charge into one molecule and link the effect to a neighboring molecule. That suggests it might be possible to extend the effect into a fabric of trillions of atom-size switches in the future.

The laboratory advances are far from being ready to commercialize, but they provide hope for the electronics industry, which has grown steadily because of the continuous shrinking in size and falling cost of components for more than four decades.

转摘:Office boy

八月 31, 2007

A jobless man applied for the position of “office boy” at Microsoft.

The HR manager interviewed him then watched him cleaning the floor as a test. “You are employed” he said. “Give me your e-mail address and I’ll send you the application to fill in, as well as date when you may start”.

The man replied “But I don’t have a computer, neither an email.”

“I’m sorry”, said the HR manager, “If you don’t have an email, that means you do not exist. And who doesn’t exist, cannot have the job.”

The man left with no hope at all. He didn’t know what to do, with only $10 in his pocket. He then decided to go to the supermarket and buy a 10Kg tomato crate. He then sold the tomatoes in a door to door round. In less than two hours, he succeeded to double his capital. He repeated the operation three times, and returned home with $60.

The man realised that he can survive by this way, and started to go everyday earlier, and return late. Thus, his money doubled or tripled everyday.

Shortly, he bought a cart, then a truck, then he had his own fleet of delivery vehicles. 5 years later, the man is one of the biggest food retailers in the US . He started to plan his family’s future, and decided to have a life insurance. He called an insurance broker, and chose a protection plan. When the conversation was concluded, the broker asked him his email.

The man replied, “I don’t have an email.” The broker answered curiously, “You don’t have an email, and yet have succeeded to build an empire. Can you imagine what you could have been if you had an email?!!”

The man thought for a while and replied, ” Yes, I’d be an office boy at Microsoft!”

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这是我自俊延的blog转载过来的一篇文章。对我来说,这篇提出了这么个道理:不入流也能成功,入流却不一定成功。

Editorial
Published: August 29, 2007

The economic party is winding down and most working Americans never even got near the punch bowl.

The Census Bureau reported yesterday that median household income rose 0.7 percent last year — its second annual increase in a row — to $48,201. The share of households living in poverty fell to 12.3 percent from 12.6 percent in 2005. This seems like welcome news, but a deeper look at the belated improvement in these numbers — more than five years after the end of the last recession — underscores how the gains from economic growth have failed to benefit most of the population.

The median household income last year was still about $1,000 less than in 2000, before the onset of the last recession. In 2006, 36.5 million Americans were living in poverty — 5 million more than six years before, when the poverty rate fell to 11.3 percent.

And what is perhaps most disturbing is that it appears this is as good as it’s going to get.

Sputtering under the weight of the credit crisis and the associated drop in the housing market, the economic expansion that started in 2001 looks like it might enter history books with the dubious distinction of being the only sustained expansion on record in which the incomes of typical American households never reached the peak of the previous cycle. It seems that ordinary working families are going to have to wait — at the very minimum — until the next cycle to make up the losses they suffered in this one. There’s no guarantee they will.

The gains against poverty last year were remarkably narrow. The poverty rate declined among the elderly, but it remained unchanged for people under 65. Analyzed by race, only Hispanics saw poverty decline on average while other groups experienced no gains.

The fortunes of middle-class, working Americans also appear less upbeat on closer consideration of the data. Indeed, earnings of men and women working full time actually fell more than 1 percent last year.

This suggests that when household incomes rose, it was because more members of the household went to work, not because anybody got a bigger paycheck. The median income of working-age households, those headed by somebody younger than 65, remained more than 2 percent lower than in 2001, the year of the recession.

Over all, the new data on incomes and poverty mesh consistently with the pattern of the last five years, in which the spoils of the nation’s economic growth have flowed almost exclusively to the wealthy and the extremely wealthy, leaving little for everybody else.

Standard measures of inequality did not increase last year, according to the new census data. But over a longer period, the trend becomes crystal clear: the only group for which earnings in 2006 exceeded those of 2000 were the households in the top five percent of the earnings distribution. For everybody else, they were lower.

This stilted distribution of rewards underscores how economic growth alone has been insufficient to provide better living standards for most American families. What are needed are policies to help spread benefits broadly — be it more progressive taxation, or policies to strengthen public education and increase access to affordable health care.

Unfortunately, these policies are unlikely to come from the current White House. This administration prefers tax cuts for the lucky ones in the top five percent.

By CLAUDIA H. DEUTSCH
Published: August 29, 2007

EVER since “An Inconvenient Truth,” Al Gore has been the darling of environmentalists, but that movie hardly endeared him to the animal rights folks. According to them, the most inconvenient truth of all is that raising animals for meat contributes more to global warming than all the sport utility vehicles combined.

The biggest animal rights groups do not always overlap in their missions, but now they have coalesced around a message that eating meat is worse for the environment than driving. They and smaller groups have started advertising campaigns that try to equate vegetarianism with curbing greenhouse gases.

Some backlash against this position is inevitable, the groups acknowledge, but they do have scientific ammunition. In late November, the United Nations Food and Agriculture Organization issued a report stating that the livestock business generates more greenhouse gas emissions than all forms of transportation combined.

When that report came out, People for the Ethical Treatment of Animals and other groups expected their environmental counterparts to immediately hop on the “Go Veggie!” bandwagon, but that did not happen. “Environmentalists are still pointing their fingers at Hummers and S.U.V.’s when they should be pointing at the dinner plate,” said Matt A. Prescott, manager of vegan campaigns for PETA.

So the animal rights groups are mobilizing on their own. PETA is outfitting a Hummer with a driver in a chicken suit and a vinyl banner proclaiming meat as the top cause of global warming. It will send the vehicle to the start of the climate forum the White House is sponsoring in Washington on Sept. 27, “and to headquarters of environmental groups, if they don’t start shaping up,” Mr. Prescott warned.

He said that PETA had written to more than 700 environmental groups, asking them to promote vegetarianism, and that it would soon distribute leaflets that highlight the impact of eating meat on global warming.

“You just cannot be a meat-eating environmentalist,” said Mr. Prescott, whose group also plans to send billboard-toting trucks to the Colorado Convention Center in Denver when Mr. Gore lectures there on Oct. 2. The billboards will feature a cartoon image of Mr. Gore eating a drumstick next to the tagline: “Too Chicken to Go Vegetarian? Meat Is the No. 1 Cause of Global Warming.”

The Humane Society of the United States has taken up the issue as well, running ads in environmental magazines that show a car key and a fork. “Which one of these contributes more to global warming?” the ads ask. They answer the question with “It’s not the one that starts a car,” and go on to cite the United Nations report as proof.

On its Web page and in its literature, the Humane Society has also been highlighting other scientific studies — notably, one that recently came out of the University of Chicago — that, in essence, show that “switching to a plant-based diet does more to curb global warming than switching from an S.U.V. to a Camry,” said Paul Shapiro, senior director of the factory farming campaign for the Humane Society.

The society, Mr. Shapiro said, is not only concerned with what happens to domesticated animals, but also with preventing the carnage that global warming could cause to polar bears, seals and other wildlife. “Our mission is to protect animals, and global warming has become an animal welfare issue,” he said.

Even tiny pro-veggie operations are starting to squeeze dollars out of their shoestring budgets to advertise the eating meat/global warming connection. Vegan Outreach, a 14-year-old group in Tucson with just three full-time workers and a $500,000 annual budget, is spending about $800 this month to run ads and links to its Web page on about 10 blogs. And, it will give more prominence to the global warming aspect of vegetarianism in the next batch of leaflets it orders.

“We know that vegetarian organizations have sometimes made exaggerated health and environmental claims, but that U.N. report is an impartial, unimpeachable source of statements we can quote,” said Matt Ball, executive director of Vegan Outreach.

Like Mr. Prescott, Mr. Ball is incensed that high-profile people like Al Gore — or environmental groups with deeper pockets than his — have not stepped up to the plate.

“Al Gore calls global warming an existential risk to humanity, yet it hasn’t prompted him to change his diet or even mention vegetarianism,” he complained. “And I guess the environmentalists recognize that it’s a lot easier to ask people to put in a fluorescent light bulb than to learn to cook with tofu.”

Advertising specialists warn that this new attention to global warming may attract enemies as well as converts.

“Using global warming as a tactic for advancing the cause of vegetarianism feels a bit opportunistic,” said Hank Stewart, senior copywriter at Green Team Advertising, which specializes in environmentally themed ads.

He also questions the logistics. “You want to get the message as close to the meat-purchasing moment as possible,” he said, “but can you imagine a supermarket allowing ‘Attention, Planet-Destroying Carnivores’ on the in-store radio?”

Environmental groups, meanwhile, readily concede that mobilizing against meat eaters is not their highest priority.

“We try to be strategic about doing the things where each unit of effort has the most impact,” said Carl Pope, executive director of the Sierra Club. Mr. Pope notes that his group has stopped short of castigating people for driving S.U.V.’s or building overly large homes, too.

“We’ll encourage companies to make more efficient S.U.V.’s, and we’ll encourage consumers to buy them,” he said, “but we do not find lecturing people about personal consumption choices to be effective.”

Environmental Defense is also “in agreement on the value of eating less meat,” said Melanie Janin, director of marketing communications. But, she added, her group would rather spend its time and money influencing public policy — specifically, getting Congress to regulate greenhouse gases.

Mr. Gore declined to make himself available for comment. Chris Song, his deputy press secretary, simply noted that a suggestion to “modify your diet to include less meat” appears on Page 317 of Mr. Gore’s book version of “An Inconvenient Truth.”

He did not address Mr. Gore’s personal food choices.

我一直对potential和energy function感到不解,没想到今天会在Fitness landscape的解释里从另外一个角度明白到底potential和energy function为何物。

from wikipedia:

Fitness landscapes in evolutionary optimization

Apart from the field of evolutionary biology, the concept of a fitness landscape has also gained importance in evolutionary optimization methods such as genetic algorithms or evolutionary strategies. In evolutionary optimization, one tries to solve real-world problems (e.g., engineering or logistics problems) by imitating the dynamics of biological evolution. For example, a delivery truck with a number of destination addresses can take a large variety of different routes, but only very few will result in a short driving time. In order to use evolutionary optimization, one has to define for every possible solution s to the problem of interest (i.e., every possible route in the case of the delivery truck) how ‘good’ it is. This is done by introducing a scalar-valued function f(s) (scalar valued means that f(s) is a simple number, such as 0.3, while s can be a more complicated object, for example a list of destination addresses in the case of the delivery truck), which is called the fitness function or fitness landscape. A high f(s) implies that s is a good solution. In the case of the delivery truck, f(s) could be the number of deliveries per hour on route s. The best, or at least a very good, solution is then found in the following way. Initially, a population of random solutions is created. Then, the solutions are mutated and selected for those with higher fitness, until a satisfying solution has been found.

Evolutionary optimization techniques are particularly useful in situations in which it is easy to determine the quality of a single solution, but hard to go through all possible solutions one by one (it is easy to determine the driving time for a particular route of the delivery truck, but it is almost impossible to check all possible routes once the number of destinations grows to more than a handful).

The concept of a scalar valued fitness function f(s) also corresponds to the concept of a potential or energy function in physics. The two concepts only differ in that physicists traditionally think in terms of minimizing the potential function, while biologists prefer the notion that fitness is being maximized. Therefore, multiplying a potential function by -1 turns it into a fitness function, and vice versa.

nucifera:这是一篇非常有意思的科研文章,主题围绕一个很有趣的现象:直觉。

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By CLAUDIA DREIFUS
Published: August 28, 2007

Two years ago, when Malcolm Gladwell published his best-selling “Blink: The Power of Thinking Without Thinking,” readers throughout the world were introduced to the ideas of Gerd Gigerenzer, a German social psychologist.

Dr. Gigerenzer, the director of the Max Planck Institute for Human Development in Berlin, is known in social science circles for his breakthrough studies on the nature of intuitive thinking. Before his research, this was a topic often dismissed as crazed superstition. Dr. Gigerenzer, 59, was able to show how aspects of intuition work and how ordinary people successfully use it in modern life.

And now he has written his own book, “Gut Feelings: The Intelligence of the Unconscious,” which he hopes will sell as well as “Blink.” “I liked Gladwell’s book,” Dr. Gigerenzer said during a visit to New York City last month. “He’s popularized the issue, including my research.”

Q: O.K., let’s start with basics: what is a gut feeling?

A: It’s a judgment that is fast. It comes quickly into a person’s consciousness. The person doesn’t know why they have this feeling. Yet, this is strong enough to make an individual act on it. What a gut instinct is not is a calculation. You do not fully know where it comes from.

My research indicates that gut feelings are based on simple rules of thumb, what we psychologists term “heuristics.” These take advantage of certain capacities of the brain that have come down to us through time, experience and evolution. Gut instincts often rely on simple cues in the environment. In most situations, when people use their instincts, they are heeding these cues and ignoring other unnecessary information.

Q: In modern society, gut thinking has a bad reputation. Why is that?

A: It is not thought to be rational. One of the founders of your country, Benjamin Franklin, suggested to his nephew that when he made important life decisions, he should do it like a bookkeeper — list all the pros and cons and then make the decision, after weighing everything. That is the classical rational approach.

Q: I make my decisions that way. What’s wrong with it?

A: In some situations, that demands too much information. Plus, it’s slow. When a person relies on their gut feelings and uses the instinctual rule of thumb “go with your first best feeling and ignore everything else,” it can permit them to outperform the most complex calculations.

In the 1990s, I was living in Chicago, where there are high dropout rates from the high schools. People often asked, “Is there a way to know which school has the lowest dropout rate?” There existed data measuring different cues of school performance: the pay of teachers, the number of English-speaking students in a class, things like that.

I wondered: could one feed these into a computer, analyze them and obtain a prediction on which high school produced the fewest dropouts? We did that. And we were astonished to find that computer-based versions of Franklin’s bookkeeping method — a program that weighed 18 different cues — proved less accurate than going with the rule of thumb of “get one good reason and ignore the rest of the information.”

Q: What was the “one good reason” that got you the right answer?

A: Knowing which school had high daily attendance rates. If two schools had the same attendance levels, you needed one more cue — good writing scores — and then you could ignore the rest.

Q: You are the author of a famous study on how people use instinct in investing. Why this topic?

A: Because intuition often underlies stock picking. Ordinary investors will frequently pick a company they’ve heard of before. We call this the “recognition heuristic,” and it basically means “go with what you know.” I was curious: is this effective? In the 1990s, we interviewed 360 pedestrians in Chicago and Munich. We asked if they were familiar with the names of German and American corporations traded on the stock exchange. Using the names of the most frequently recognized companies, we then made up investment portfolios.

After six months, the high-recognition portfolios, on average, gained more value than the Dow and DAX markets and some big-name mutual funds. The high-recognition portfolios did better than a portfolio we created from randomly picked stocks and another made up of low-recognition stocks. Over the years, we’ve repeated this experiment twice, in different ways. Each time, the intuitive wisdom of the semi-ignorant outperformed the calculations of the experts.

Q: Have you considered going to your pedestrians for investment advice?

A: Yes! I did that once. I invested $50,000 in high-recognition stocks picked by the least stock-savvy group we studied, those German pedestrians. Their portfolio went up 47 percent in six months, as opposed to the 34 percent gains made by the German stock market as a whole. This was during a bull market.

Q: Where can gut instincts fail?

A: Here’s an example: after 9/11, many Americans stopped traveling in airplanes and drove on highways instead. I looked at the data, and it turned out that in the year after the attacks, highway fatalities increased by an estimated 1,500 people. They had listened to their fear, and so more died on the road. These kinds of fatalities are easily avoided. But psychology is not taken very seriously by governments. Most of the research about how to combat terrorism is about technology and bureaucracy — homeland security. In this case, educating the public about their own gut reactions could have saved lives.

Q: Some of your critics say that gut instincts just aren’t scientific. What’s your answer?

A: We study these things, where intuition is good and where it’s not. One should also not overlook that in science itself, you need intuitions. All successful research scientists function, to a degree, on gut instincts. They must make leaps, whether they have all the data or not. And at a certain moment, having the data doesn’t help them, but they still must know what to do. That’s when instinct comes in.

Q: Do you think of yourself as intuitive or rational?

A: Both. In my scientific work, I have hunches. I can’t explain always why I think a certain path is the right way, but I need to trust it and go ahead. I also have the ability to check these hunches and find out what they are about. That’s the science part. Now, in private life, I rely on instinct. For instance, when I first met my wife, I didn’t do computations. Nor did she.

Q: Shakespeare’s “Hamlet” is about a young man who doesn’t respond to his first best instinct, which is to avenge his father’s murder by killing his uncle. If Hamlet had listened to his gut, how would the play be different?

A: This is not a scientific kind of question. But the play would have been shorter and probably fewer people would have been killed.