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Ecodefense, Heinrich Boell Stiftung Russia, Alla Slapovskaya, Alisa Nikulina via Wikimedia Commons // Public Domain

The Kyshtym Disaster: The Largest Nuclear Disaster You've Never Heard Of

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Ecodefense, Heinrich Boell Stiftung Russia, Alla Slapovskaya, Alisa Nikulina via Wikimedia Commons // Public Domain

When you think of nuclear disasters, you think of the Chernobyl plant in Ukraine and the Fukushima plant in Japan, and maybe Three Mile Island. But after Fukushima and Chernobyl, the third biggest nuclear disaster is called Kyshtym. Never heard of it? That’s because it happened in 1957, at the height of the Cold War, deep in the eastern Ural Mountains of the Soviet Union. The Soviets disclosed details to no one, not even the people affected. Even the name is a misdirection, because it didn’t happen in Kyshtym. It was in the town of Chelyabinsk-65 (which was renamed Ozyorsk in the early 1990s); this town, according to the Soviets, did not exist.

The Mayak Production Association runs plutonium facility No 817 in the Chelyabinsk region of Russia. During the Soviet era, its location was a secret to anyone who didn't work there. It was known as Chelyabinsk-40 after the postal code, and the nearby community was named Chelyabinsk-65. The facility was built in a hurry just after World War II in order to catch up with the Americans in nuclear weapons technology. The plant, which included six reactors, processed nuclear materials to develop weapons-grade plutonium. At the time, relatively little was known about the effects of radioactive materials on human workers, and even the dangers that were known were disregarded by Soviet authorities in their haste to develop nuclear weapons. The future town of Ozyorsk grew up around the facility.

Carl Anderson, US Army Corps of Engineers via Wikimedia Commons // Public Domain

The plant was dangerous from the beginning. Radioactive waste was disposed of by dumping it into the Techa River. Solid waste was dumped on-site, and smoke was released into the air with no regard to its contents. Protective gear for the workers was minimal, and most of it was believed to have been done with forced labor from local prisoners. The first recorded nuclear accident there occurred in 1953, but went unnoticed until a worker developed radiation sickness (his legs were eventually amputated due to radiation burns, but he survived). Four other workers were affected as well. It was the first of dozens of incidents at the facility that continued for decades.

On September 29, 1957, one of the Mayak plant’s cooling systems failed. No one noticed until it was too late. A waste tank exploded, sending a cloud of radioactive material into the air, which fell over an area of 20,000 square kilometers. Though 270,000 people lived there, only 11,000 were evacuated (and that took up to two years to accomplish). Those who remained were pressed into service to clean up the debris by destroying contaminated crops and livestock. They worked without protection from radiation, and then they went back to their homes.   

Jan Rieke, via Wikimedia Commons // CC BY-SA 3.0

The Soviet reaction was a puzzle to many of the peasants who lived near the Mayak plant. In the village of Korabolka, farmers thought a global nuclear war had begun when they saw the explosion. Within a few days, 300 of the village’s 5000 residents died of radiation poisoning. An evacuation was planned, but only ethnic Russians were relocated. The remaining half of the village were ethnic Tatars, who were left in place. In the more than 50 years since, many villagers are convinced they were left as an experiment. The cancer rate for Korabolka, now called Tatarskaya Korabolka, is five times that of an uncontaminated village. Other villages around the region report elevated rates of cancer, genetic abnormalities, and other illness. 

The Western press knew very little about the event. There were rumors, but no concrete details until 1976, when biologist and Soviet dissident Dr. Zhores Medvedev published an account of the disaster in New Scientist. As late as 1982, scientists in the West displayed doubt that contamination in the area was due to a nuclear accident instead of industrial pollution. Information came out in small pieces until the fall of the Soviet Union.  

Ecodefense, Heinrich Boell Stiftung Russia, Alla Slapovskaya, Alisa Nikulina via Wikimedia Commons // Public Domain

The Kyshtym disaster is not the only reason that Chelyabinsk is so contaminated. The waste that was dumped in the Techa River from 1949 to 1956 still claims victims in the villages downriver. In Muslumovo, those who weren’t evacuated in the 1950s and '60s were left in place and were tended to by national radiation experts who were studying the subjects of “a natural experiment” to glean information on the effects of nuclear war on humans. The villagers were not told of the research, and were kept in the dark as to why so many of them were sick. It was only in 1992, when Soviet records were declassified, that the nature of the Muslumovo experiment was uncovered. Even then, one pediatrician estimated that 90% of the village’s children suffered from genetic abnormalities, and only 7% were considered healthy.

Sergey Nemanov via Wikimedia Commons // CC BY-SA 3.0

The Mayak plant stopped processing weapons-grade plutonium in 1987, but still operates in Chelyabinsk, reprocessing spent nuclear fuel shipped in from all over Russia. The safety features of the plant have been vastly upgraded from those of Soviet era. The current level of danger from radiation at the plant is in dispute.

MemphiStofel via Wikimapia // CC BY-SA 3.0

The area around the reactor site has been called the most contaminated place on earth. The villagers who were affected by the disaster and the long-term industrial pollution are still fighting for relocation and compensation. We will probably never know how many people died from nuclear contamination, for several reasons, and it's also difficult to pinpoint the extent of the contamination a half-century ago. And Soviet suppression of information and documentation makes current research on the incident extremely difficult. Even today, Russia doesn't welcome challenges to its official version of the story. 

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iStock // Ekaterina Minaeva
Man Buys Two Metric Tons of LEGO Bricks; Sorts Them Via Machine Learning
May 21, 2017
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iStock // Ekaterina Minaeva

Jacques Mattheij made a small, but awesome, mistake. He went on eBay one evening and bid on a bunch of bulk LEGO brick auctions, then went to sleep. Upon waking, he discovered that he was the high bidder on many, and was now the proud owner of two tons of LEGO bricks. (This is about 4400 pounds.) He wrote, "[L]esson 1: if you win almost all bids you are bidding too high."

Mattheij had noticed that bulk, unsorted bricks sell for something like €10/kilogram, whereas sets are roughly €40/kg and rare parts go for up to €100/kg. Much of the value of the bricks is in their sorting. If he could reduce the entropy of these bins of unsorted bricks, he could make a tidy profit. While many people do this work by hand, the problem is enormous—just the kind of challenge for a computer. Mattheij writes:

There are 38000+ shapes and there are 100+ possible shades of color (you can roughly tell how old someone is by asking them what lego colors they remember from their youth).

In the following months, Mattheij built a proof-of-concept sorting system using, of course, LEGO. He broke the problem down into a series of sub-problems (including "feeding LEGO reliably from a hopper is surprisingly hard," one of those facts of nature that will stymie even the best system design). After tinkering with the prototype at length, he expanded the system to a surprisingly complex system of conveyer belts (powered by a home treadmill), various pieces of cabinetry, and "copious quantities of crazy glue."

Here's a video showing the current system running at low speed:

The key part of the system was running the bricks past a camera paired with a computer running a neural net-based image classifier. That allows the computer (when sufficiently trained on brick images) to recognize bricks and thus categorize them by color, shape, or other parameters. Remember that as bricks pass by, they can be in any orientation, can be dirty, can even be stuck to other pieces. So having a flexible software system is key to recognizing—in a fraction of a second—what a given brick is, in order to sort it out. When a match is found, a jet of compressed air pops the piece off the conveyer belt and into a waiting bin.

After much experimentation, Mattheij rewrote the software (several times in fact) to accomplish a variety of basic tasks. At its core, the system takes images from a webcam and feeds them to a neural network to do the classification. Of course, the neural net needs to be "trained" by showing it lots of images, and telling it what those images represent. Mattheij's breakthrough was allowing the machine to effectively train itself, with guidance: Running pieces through allows the system to take its own photos, make a guess, and build on that guess. As long as Mattheij corrects the incorrect guesses, he ends up with a decent (and self-reinforcing) corpus of training data. As the machine continues running, it can rack up more training, allowing it to recognize a broad variety of pieces on the fly.

Here's another video, focusing on how the pieces move on conveyer belts (running at slow speed so puny humans can follow). You can also see the air jets in action:

In an email interview, Mattheij told Mental Floss that the system currently sorts LEGO bricks into more than 50 categories. It can also be run in a color-sorting mode to bin the parts across 12 color groups. (Thus at present you'd likely do a two-pass sort on the bricks: once for shape, then a separate pass for color.) He continues to refine the system, with a focus on making its recognition abilities faster. At some point down the line, he plans to make the software portion open source. You're on your own as far as building conveyer belts, bins, and so forth.

Check out Mattheij's writeup in two parts for more information. It starts with an overview of the story, followed up with a deep dive on the software. He's also tweeting about the project (among other things). And if you look around a bit, you'll find bulk LEGO brick auctions online—it's definitely a thing!

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Name the Author Based on the Character
May 23, 2017
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