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The Engineer's Notebook

The Engineer's Notebook is a shared blog for entries that don't fit into a specific CR4 blog. Topics may range from grammar to physics and could be research or or an individual's thoughts - like you'd jot down in a well-used notebook.

Time to Plant Some Trees

Posted April 25, 2016 12:00 AM by joeymac

Well its spring time and I'm sure you're getting the itch to be outside and working on your garden, pick up your yard, and get ready for outdoor projects after the long winter, especially up here in the Northeast. One outside project that people like to do and is the perfect time to do right now is planting a tree. There are multiple reasons for planting trees such as: saving a household's heating and cooling energy consumption, trees also clean the air by absorbing pollutants and carbon dioxide while producing oxygen, they provide shelter and food for wildlife, help save water by slowing evaporation, and provide food when planting fruit or nut trees.

Choosing the right tree is where your homework comes into play. Once you've decided on the reason why you're planting a tree, you need to figure out what type of tree will best fulfill your needs. If you're planting for energy savings, then you need to select a large deciduous tree, which will shade your home spring through fall while allowing the sun to shine through in the winter once its leaves have fallen. If you're looking for shade, choose a tree with a broad canopy, and if you want shade year-round, then select a tree that's evergreen and won't lose its leaves in winter. Make sure to pick a tree with the right color in mind for summer and fall foliage that fits your liking. Fruit trees give a double bonus by providing food and beauty with their spring flowers and fall foliage. Also keep tidiness in mind when picking out a tree, some trees are messier than others. If you're planting a tree near a pool, select one that won't produce messy flowers, seedpods, or both. If planting near a pool an evergreen would be ideal for keeping the water clean.

Planting is best done while the tree is dormant. This is either in the fall after the leaves have dropped or in early spring just before the leaf buds begin to swell. Planting trees during this time gives the roots time to grow before the warmer weather stimulates new top growth. Trees can be planted at any time of the year but extra care is needed to be sure they are adequately watered during their first summer.

When planting a tree, the hole's size plays a major role in how quickly a tree establishes itself and grows. The hole should be three times wider than the trees root ball and shaped like a saucer. This allows for good root growth and development, because the majority of a tree's roots grow outward into the top foot of soil where oxygen is at high levels. The hole should be the same depth as the root ball or even slightly shallower. Trees don't like to be planted too deeply because it decreases the amount of oxygen available to the roots. Also, trees tend to settle a little lower after being planted. When picking the planting site remove any excess soil on top of the root ball, place the tree in the center of the hole. Fill the hole with the same soil that was dug out, after filling in the hole create a berm around the hole which will hold water to help it permeate deeply around the tree and water immediately after planting to settle the soil and get rid of air pockets. No fertilizer or any other amendments should be added during planting or for the first year, as this could hurt the tree's roots. New trees will need more water for the first year to help them get established, especially the first few weeks after planting. Add a 2 to 4 inch layer of mulch, compost, or wood chips around the tree. Keep the mulch 6 inches away from the trunk to prevent fungal disease or insect problems.

16 comments; last comment on 04/27/2016
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Let Them Eat Weeds: Foraging in Urban Food Deserts

Posted April 22, 2016 8:00 AM by BestInShow

This week (April 17 - 23) is Wild and Feral Food Week. I'd planned to follow last week's blog about eating invasive plant species with a post about eating non-invasive wild plants, like ramps and fiddleheads, which come into their own at this time of year. Scratch that idea. Instead, let's celebrate Wild and Feral Food Week by examining the premise that urban foraging can be an effective method for improving fresh food availability. Solar Eagle's humorous response to last week's blog post got gave me the title for this week's blog: let them (or us) eat weeds. This notion is discussed by Mark Bittmann, at the time a visiting fellow at Berkeley Food Institute, as he joined Philip Stark and Tom Carlson of the University of California, Berkeley, for a walk around Oakland, CA, finding weeds to eat.

Gourmet chefs on a foraging expedition. Image credit: The Gourmet Forager

Food Deserts

First, some background. Many of you have heard of food deserts. For those of you who have not, the US Department of Agriculture's definition is "[food deserts are] parts of the country vapid of fresh fruit, vegetables, and other healthful whole foods, usually found in impoverished areas. This is largely due to a lack of grocery stores, farmers' markets, and healthy food providers." The definition specifically calls out lack of a car plus no grocery store within one mile as main factors in the food desert definition. The map in the link above shows that we can find deserts in rural areas as well as urban environments.

The West Oakland neighborhood through which Bittmann, Stark, and Carlson took their tour has long been considered a food desert. A 1960s-era freeway project split West Oakland from the rest of the city, hastening the neighborhood's descent into poverty. Several supermarkets have come and gone; currently, West Oakland is waiting for yet another supermarket project to get off the ground. A food-co-op and a couple of smaller enterprises are helping improve the food scene, but these stores cannot adequately serve West Oakland's population of around 37,000.

A Walk on the Wild Side (you saw that coming)

Stark and Carlson are principal investigator and co-investigator, respectively, for Berkeley Open Source Food, an initiative that, among other goals, seeks to increase foraging for

urban wild-grown greens. My first reaction to eating a plant I pulled up from a sidewalk crack was, as you might think, yuck. The uber-foragers address the yuck factor directly. Yes, these plants can be dusty. A dog might have watered them. However, plants are washable; no one says you have to eat them as soon as they are picked. An interesting point in the weeds' favor is that these plants are free of the pesticides commonly used on field crops and even in home gardens and lawns. Free-range weeds have several other plusses:

  • They're free.
  • They're organic. Think about that: organic weeds!
  • They require no cultivation or other care.
  • They're drought-tolerant.
  • Many are nutritionally superior to cultivated counterparts.
  • They're ubiquitous

The foraging trio quickly found a basketful of greens. All of you readers who have lawns will recognize some, if not all, of these usual suspects. The New York Times published a guide with pictures and serving suggestions (see link in Resources).

Please note: if you are interested in foraging, do your homework on plant identification before you taste anything. When you taste, start with a small bite and wait to ensure that you are not allergic to the plant. The Berkeley Food Initiative web site has a good guide, and there are plenty more on the internet.

  • Chickweed (Stellaria media): "tastes like spring," according to Bittmann
  • Sweet fennel (Foeniculum vulgare): milder and sweeter than commercial varieties
  • Yarrow (Achillea millefolium): sagelike flavor
  • Wood sorrel (Oxalis acetosella): lemony and crunchy
  • Sheep sorrel (Rumex acetosella): a "bright" taste
  • Nasturtium (Tropaeolum majus): peppery and succulent
  • Wild radish (Raphanus raphanistrum): mustard-hot and slightly sweet
  • Bristly ox tongue (Echioides helminthotheca): beefy or mushroomy flavor

A Cool Smart Phone App

Urban weed foraging in the East Bay has a nifty technological assistant. Berkeley Open Source Food encourages use of the iNaturalist smart phone application designed to make foraging easier and safer. Foragers provide a real-time weed inventory/mapping/visual index for Berkeley, Oakland and Richmond. iNaturalist exploits smart phones' GPS capability and cameras to enable individuals to post locations and pictures of various plant species. There's a competitive aspect to posting information: current leaders in "most species" and "most observations" are listed on the site. The screenshot below illustrates the "leaderboard."

The iNaturalist plant-mapping project is a testbed to determine the feasibility of urban foraging. The website claims that participants have found "vast quantities of delicious fresh natural greens in economically challenged parts" of the three cities covered. How "vast quantities" translates to number of people who get to eat fresh salad, and who those people are, are questions that the research project seeks to answer. Even if an urban area produces enough weeds to feed everyone in the city, who will eat them? Food carries all manner of socio-economic and cultural connotations, in addition to the yuck factor. Will an urban family eat weeds if family members feel this reflects negatively on them? Are there cultural barriers to eating some of these plants? Given the general opinion that California's East Bay is way out there, can it be replicated elsewhere or will the association doom it to implementation in few other locations.

I'm not immune to weed prejudice. A few years ago, I got a pile of purslane in my CSA (community-supported agriculture) weekly bag. Since I'd just spent a lot of time pulling purslane out of my flower beds, I wasn't happy to have paid for a fresh batch. After reading Bittmann's favorable reactions to most of the weeds he tasted, though, I'm inclined to give purslane a taste. After all, the cultivated plants we eat all started out as something wild.

Image credits: Berkeley Food Institute, iNaturalist


9 comments; last comment on 04/25/2016
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If You Can't Kill Them, Eat Them

Posted April 15, 2016 8:00 AM by BestInShow

My blog post last year about invasive plant species led me figuratively out into the weeds. I pursued a couple of threads that led into the world of foragers. From these expert foragers, I learned that some of my favorite foreign invaders are edible. I also discovered a lot of noninvasive species are not only edible but nutritious. This post will look at three purportedly tasty invasive plants. My next post will follow up on foraging and look at the potential for weeds to provide nutrition for hungry people.

Garlic Mustard

People in the western Baltic cooked with Garlic mustard (Alliaria petiolata) as far back as 6100 BP. Eastern European immigrants brought this familiar pot herb with them to the US in the 1860s and used it for food and for medicinal purposes. In addition

to imparting a mild garlic flavor to dishes, it is a good source of vitamins A and C. Non-food uses include it as a disinfectant and a diuretic. Garlic mustard - also known as Garlic Root, Hedge Garlic, Poor Man's Mustard, and my favorite, Jack-by-the-Hedge - presents a significant hazard to other plant life, native and introduced. This biennial invader outcompetes for resources, and its roots exude a toxic chemical that kills off arbuscular mycorrhizal fungi (AMF), which form mutually beneficial relationships with many forest trees. No AMF, bad news for trees. That's why it's on "least wanted" plant lists all over the US.

That said, this stuff IS edible, nutritious, widely available, and free; it's already growing lushly on our property in upstate New York. There's even a cookbook, cleverly titled From Pest to Pesto: A Culinary Guide, published by the Appalachian Forest Heritage Association. The subtitle is "Eat It to Beat It." I sincerely doubt that we can make a dent in garlic mustard by eating it. There's nothing wrong with trying, though. Recipes for the leaves run from pesto to salad to sauce for roast beef. The roots are spicy, like horseradish. Chicken weed wrap, anyone?

Japanese Knotweed

Japanese knotweed (Fallopia japonica in Europe, Polygonum cuspidatum Sieb. & Zucc. in the US), a member of the Buckwheat family, is related to rhubarb. When it

was first introduced in Holland (1845) and England (1850), horticulturists saw its potential both as cattle feed and as a lovely addition to the garden. By the early 1900s, though, gardeners were learning that this plant spreads quickly and is nearly impossible to contain. By this time, the plant was also established in the United States. The first time I saw knotweed in bloom, I thought it was an attractive plant. I've since learned that, at least in England, an infestation of knotweed lowers house values.

Japanese knotweed is edible - a "dreadable edible," according to Eat the Weeds. Like garlic mustard, this noxious weed is also very nutritious, a major source of resveratrol and Vitamin C. Edible parts of the plant include young shoots and growing tips, which can be steamed and eaten like asparagus. On the page link in the previous paragraph, I found recipes for a dessert puree and Japanese Knotweed Bread. Rebecca Louie, writing in the Huffington Post, suggests "eating the enemy" in the form of fruit leather. The rhizome, the thick underground stem by which knotweed spreads itself, is particularly rich in resveratrol. Resveratrol supposedly has potent medicinal effects, but current research has uncovered little evidence that resveratrol is a miracle compound.


Those CR4 members who live outside the US might not know that the Kudzu vine, Pueraria montana, is a symbol of the Southern US. Not an attractive symbol, like the Southern magnolia, but one referred to as the vine that ate the South. This rapidly-growing vine was introduced from Japan to the US at Philadelphia's Centennial Exposition (1876), as part of an exhibit of native Japanese plants. The glossy leaves and fragrant flowers made kudzu an attractive addition to gardens, mainly in the South. Fast forward to the Great Depression and the Civilian Conservation Corps, one of whose mandates was to stop erosion of farm soil. Their solution? Kudzu. Kudzu is also useful for animal feed, and since it is a legume, it increases soil nitrogen through a symbiotic relationship with nitrogen-fixing bacteria. It does stop soil erosion, but good luck getting rid of its roots and runners in order to plant anything else.

Kudzu is arguably a more valuable invasive plant than the other two discussed here; all parts of the plant are useful. The vines make excellent baskets; you could use one

to hold your harvested kudzu. Chinese traditional medicine has long used various parts of the plant to treat ailments ranging from high blood pressure, to digestive disorders, to alcoholism. One writer says it's the perfect nightcap. And it improves the soil.

Where kudzu really stands out, though, is the variety of edibles cooks have coaxed out of it. The roots can be used in soup or a tea. The leaves are endlessly useful, cooked like collard greens,e.g., stewed in salt pork until tender, or stuffed like Dolmades. Steam the leaves, chop them up, and put them in a quiche. Or make jelly from the flowers. Or make wine from the flowers. The Kudzu Cookbook (Carole March Longmeyer, 2015) and Kudzu Cuisine (Juanitta Baldwin, 2011) will tell you everything you need to know. You just have to get your hands on some kudzu, which won't be easy unless you live where it grows. I doubt anyone would want you to bring kudzu back from a trip down South … like the other two plants in this blog, it's the gift that keeps on giving, whether you like it or not.

Image credits:; The Compostess; Wikimedia Commons


15 comments; last comment on 04/19/2016
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Scents and Scentsibility

Posted April 08, 2016 8:00 AM by BestInShow

When I work in my home office, I usually light a candle. I do this in part because I like the scent and in part because I've read that certain scents improve productivity. Why, I wondered, does peppermint reputedly help someone focus better than honeysuckle or popcorn or that old fave from the '60s, patchouli? As usual, my search branched off in unexpected directions. I discovered that unraveling the science behind our sense of smell earned a 2004 Nobel Prize for two scientists. And on a less-grand level, marketers, not surprisingly, use scent as another arrow in their quiver of tools to get us to buy stuff. And in 2013 a British company commissioned a specific workplace fragrance (Ascent) from a master perfumer. This is serious business.

Physiology of smell

Richard Axel and Linda Buck were awarded the 2004 Nobel Prize for Medicine or Physiology, "for their discoveries of odorant receptors and the organization of the olfactory system." Their research was on gene coding for proteins expressed exclusively in the olfactory epithelium. Humans have around 300 genes that cooperate in identifying smells. The laureates discovered that each gene codes for one type of olfactory receptor, and each receptor "recognizes" a limited number of odorants.

Receptors are protein chains whose shape alters when an odorant substance attaches itself to the receptor. Only receptors genetically programmed to recognize the odorant will be activated. These receptors send these bits of information to the olfactory bulb in the brain. The brain, in turn, recognizes the different chemical components and combines the bits into a completely individual smell.

This intricate system enables humans to recognize 10,000 individual smells and to remember a new smell with 65% accuracy after a year. Don't be overly impressed. Dogs possess up to 300 million olfactory receptors in their noses, compared to about six million in us. And the dog's olfactory bulb is, proportionally speaking, 40 times greater than ours.

Humans and scent

The sense of smell is the first sense that we humans (and other mammals) use. Think about it. Evolutionarily, being able to find one's mother, or sense an enemy, from birth is critical to survival. Being able to remember significant scents -- and dangerous smells - is equally important. The close connection between the olfactory bulb and the limbic system, a part of the brain that governs emotion and memories, accounts for our ability to learn and remember smells.

Based on personal observation, I'm well aware that humans remember scents and that these scents often evoke emotion, even long after the original exposure or the event that connected the scent to the emotion. Every time I peel an orange or a tangerine, I think of Christmas mornings when I was a kid. How much of what we read or hear do we remember that vividly?

Scent marketing

Scent memory is one attribute that marketers exploit. One example: a luxury-goods store that pumps in the aroma of old leather, among others. Old leather evokes craftsmanship. Do not think that scent marketing nabs just the marginal customers who might not otherwise buy something. Research proves that people buy more in an appropriately-scented environment compared to an eau de ordinary shopping mall.

Back to Scent and Productivity

A number of well-regarded empirical studies have established that, even if we cannot

yet explain why, some scents do improve various aspects of productivity at work.

Masahiro Tanida and Masako Katsuyama of the Bioengineering Research Laboratories, at the Shiseido Life Science Research Center, in Yokohama, in conjunction with Kaoru Sakatani of the Department of Neurological Surgery, at Nihon University School of Medicine, tested the effect of a "pleasant, floral green" scent on volunteers

performing a mental arithmetic problem. Over the four-week course of the experiment, the researchers measured stress reduction in the experimental group.

A handful of other studies focused on cognitive performance and accuracy. Cinnamon and peppermint scents generally improved attention and memory. Typists exposed to peppermint typed faster and more accurately than the control group. Another study found that females responded better to lavender in tests of memory and accuracy; men responded better to peppermint.

Several less-rigorous surveys expand the range of productivity-inducing scents. The effects of the suggested scents are usually either stimulants - peppermint, citrus, cinnamon, eucalyptus - or stress-relievers - lavender, rosemary, and jasmine. Some lists are more inclusive, but this set of seven scents is the core of the productivity-enhancing arsenal.

Why Does Scent Work?

My search for empirical research explaining why some scents increase productivity in the workplace did not turn up definitive answers. A number of the scent marketing studies posited that the memories and associations between specific scents, such as evergreen trees and the Christmas holidays, put consumers in a happy place, so to speak, and happy people are more inclined to spend money. Do we work better because we're feeling less stressed or happier?

I haven't conducted any unscientific studies on myself and my home office. I did once engage in a slightly different kind of scent experiment. I'd read that the Monell Chemical Senses Center in Philadelphia concluded that two scents, pumpkin pie and lavender, were the most attractive to men. I conscientiously wore lavender the whole time my husband I and were dating and, well, he's my husband now. Did the lavender tip the scales in my favor? If it did, I'm glad it worked out.


Image credits

Ambiente Bio

37 comments; last comment on 04/12/2016
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Are Your Smarter (or Dumber) Than Your Ancestors?

Posted April 06, 2016 3:00 PM by HUSH
Pathfinder Tags: education history intelligence IQ

The Case for Being Dumber

It's easy to find anecdotal evidence about how 'stupid' the world has become. Take a look at the millions of tacky social media posts. Consider that new age celebrities are pretty much normal people live-playing video games or doing a stunt on YouTube. The average person's job might soon be replaced with AI and a robot, because so many jobs and tasks are menial and repetitive.

It's more difficult to find scientific evidence about a global decrease in general intelligence, but research does exist. According to a 2013 joint study conducted by researchers from UmeƄ University, Vrije Universiteit Brussel, University of Amsterdam and University College Cork, Western populations are 14 IQ points dumber than Victorian ancestors.

The researchers studied data from mental chronometry tests conducted between 1884 and 2004. In a mental chronometry test, participants must press a button when visually cued. Since the eyes perceive the cue and the brain commands the button press, reaction time correlates to mental acuity.

After analyzing the data researchers found that visual reaction times in the 19th Century were an average of 194 milliseconds, but in 2004 were an average of 275 milliseconds.

As possible explanation, one of the researchers indicated that there is a well-documented negative correlation between IQ and fertility-basically dumb people are likely to produce more offspring. This is sometimes called the Smart Man's Burden; though I would prefer to call it the Idiocracy principle after this clip from the 2006 movie (strong language).

The Case for Being Smarter

Look at all this technology! Cell phones, tablet computers, graphene, autonomous cars, AI-playing Go, and more. Or is this just an instance of a few very intelligent individuals enriching the lives of everyone else?

According to data from American-born and New Zealand-based professor Dr. James Flynn, each one of us is considerably smart than any of our ancestors. Flynn first hypothesized that there are substantial intelligence gains in successive generations over the past 100 years. This is called the Flynn effect.

Flynn analyzed test data from Raven's Progressive Matrices (RPMs), which are reasoning tests meant to interpret reasoning and fluid intelligence. RPMs are regularly updated and standardized so the majority of test-takers receive results with an average of IQ 100 points, with a standard deviation of 15 IQ points. When these sample test-takers also take previous iterations of the RPMs, they regularly score higher than 100 IQ points.

These improved test scores are consistent and linear. Flynn received similar results for sample test-takers born in the previous 100 years in both Iowa and Scotland. In the U.S. this is an improvement of 3 IQ points per decade, when scaled by Weschler Intelligence Scale for Children tests. Other countries note similar IQ gains, albeit at different rates of increase.

Some studies of the Flynn effect have found that many of the IQ gains happen at the lower ends of the sample distribution, which buoys IQ averages. Basically the simpletons of today are better educated than older individuals in the same part of the IQ distribution.

Flynn himself struggles to pinpoint any single reason why population IQs are going up. He believes that our modern societies are more cognitively challenging and better enable smart individuals to seek new challenges. Other researchers believe that improvements in schooling and test taking lead to better results, but not necessarily smarter people. Biological parameters, such as improving nutrition and preventative medicine, are also sometimes credited.

Nonetheless, Flynn expects there to be IQ improvement apex, where eventually IQs begin slipping as the Smart Man's Burden takes a larger presence. Some argue that it's already here.

The Verdict

So how do you feel? Are we smarter or dumber than our ancestors of 50 or 100 years ago?

There likely will never be a method to objectively evaluate this; the above are just two contradicting examples of many, many more studies about this topic.

Before you weigh in, remember the Dunning-Kruger effect: dumb people think they're smarter than they really are.

21 comments; last comment on 04/10/2016
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AI Passes 'Go'

Posted March 21, 2016 10:52 AM by Jonathan Fuller

Viewers of Darren Aronofsky's surreal film Pi in its entirety probably walked away with two lasting recollections: a man using a power drill to relieve his cluster headaches, and a romantic description of the ancient Chinese game Go. Unlike many other games of strategy, the Go board represents--as described by the character Sol Robeson--"an extremely complex and chaotic universe...and that is the truth of our world [...] it can't be easily summed up with math...there is no simple pattern."

Thanks to these attributes, Go has always been a major stumbling block for artificial intelligence. Late last year, however, Google DeepMind's AlphaGo program made a major breakthrough by defeating a highly ranked professional Go player sans handicap for the first time. More recently in a five-game match that took place from March 9-15, the program won four games against Lee Se-dol, one of the best players in the world. AI enthusiasts consider these matches major victories for the discipline, as many assumed that a competent Go program was still at least five years in the making.

Go's international appreciation is due to the fact that, despite having only two essential rules, there are a vast number of possible moves and unique games. Each player, one black and one white, takes turns placing their stones on the game board's intersections, typically forming chains. A chain which is completely surrounded by opposing stones is captured and removed from the board. A game may be scored by either the number of empty spaces a player's stones surround or the number of stones plus surrounded intersections. The only other rule is that a player may not make any move that returns the game to the position of the previous turn.

While the image on this page shows a 9x9 beginner board, professional games like those won by AlphaGo are played on a 19x19 board. AI expert Victor Allis estimates that a typical 19x19 expert game lasts 150 moves or so, with about 250 choices per move. These figures result in a game-tree complexity--a common measure of game complexity used in combinatorial game theory--of 10360. Compare this with tic-tac-toe's 26,830 or chess's 10120, and you start to see why Go is so difficult for the automated mind. (For those with enough time, patience, and interest, DeepMind's YouTube channel features all five March 2016 matches move-by-move.)

AlphaGo cracked the Go problem not by building a program adept at playing Go, like IBM's chess-playing Deep Blue, but by using a combination of more general machine learning and tree search algorithms to create a program adept at learning any game it practices and experiences. This step toward artificial general intelligence has met with differing reactions within the AI community. Most comment that it's probably a good time to discuss the social/cultural impact of this general intelligence; a year ago Stephen Hawking went so far as to suggest the possibility of a smart computer takeover. In response to the AlphaGo victories, Murray Campbell, an IBM scientist who worked on Deep Blue, more or less proclaimed the victorious end of AI board game experiments.

He might be right, but in my opinion there's no currently feasible leap from games to "real-life" general AI solutions, and computers obviously have a long way to go before (if ever) understanding human behavior beyond emulation. Carnegie Mellon's Claudico, a Texas hold 'em program that uses non-game-specific algorithms similar to AlphaGo's, lost a 2015 poker event against four top human players by over 700,000 chips. That program struggled with risky bets and bluffing, two behaviors difficult for a ruthlessly rational program to comprehend.

Much like Deep Blue in 1997 and Watson in 2011, AlphaGo's victory is one more AI milestone on the road to who knows where. But to quote Lee Se-dol after his historic defeat: "robots will never understand the beauty of the game the same way that we humans do."

Image credit: Jarrod Trainque / CC BY 2.0

6 comments; last comment on 03/23/2016
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