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6 Carnival Traditions from Around the World

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From the masked intrigues of Venice to the vibrant pulse of Rio de Janeiro, Carnival is celebrated the world over. In honor of this year’s Fat Tuesday, here are a few Carnival traditions you may not have heard about.

1. Joe Cain Day

Though New Orleans’s Mardi Gras is arguably the most famous along the Gulf Coast, Mobile, Alabama lays a proud claim to hosting the first Mardi Gras celebration in the United States. However, the local Mardi Gras celebrations dissolved in the aftermath of the Civil War until Joe Cain revived the tradition in 1867. According to legend, Cain dressed himself as a fictional Indian chief, Slacabamarinico, and marched through the city with a group of ragtag musicians who buoyed the city’s spirits. In subsequent years, bystanders were invited to step into the streets and join the parade on Joe Cain Day, the Sunday before Mardi Gras. Though the parade’s size is now more carefully controlled, the spirit of inclusion and resurgence continues.

2. Weiberfastnacht

Cologne, Germany holds one of the most famous Karneval celebrations in Europe. The festivities begin on November 11 at 11:11, dragging the holiday out for so long that it’s often called the Fifth Season. Here, on the Thursday before Shrove Tuesday, women traditionally cut men’s ties in a gesture challenging male dominance.

3. Užgavėnės

On Shrove Tuesday, many Lithuanians celebrate by burning a female effigy called Moré to signify the defeat of winter. The event is followed by symbolic battles between winter and spring that emphasize a promise of renewal. The celebration, which has pagan historical roots as well as Christian inspiration, often includes other costumed characters and features pancakes as its traditional dish.

4. Hanging Donkeys

One town in Catalonia adds an unexpected decoration to its Carnival festivities. Legend says a donkey was once sent up the narrow stairway to eat grass from the bell tower of the cathedral in Solsona. When the donkey balked, someone put a rope around its neck and tried to haul it the rest of the way. Now, stuffed donkeys are hung from the tower during Carnaval.

5. Water Fights

In Ecuador, local Carnaval celebrations feature mischievous games probably based on traditions the Huarangas Indians established. Contemporary revelers should be on guard: diablitos may be waiting to douse them with balloons filled with water or flour.

6. Courir de Mardi Gras

In Cajun communities throughout the prairies of Louisiana, Mardi Gras customs take on a colorful twist. Unlike the elaborately planned New Orleans celebration just to the east, where Mardi Gras societies control who can march in parades or attend balls, Cajun revelers invite the local community to don patchwork costumes and traipse through rural areas going door to door. Traditionally, participants can take on one of two roles: either that of capitane or courir. The capitane carries a whip and keeps the courir in order, while the courir goes from house to house begging for food and trying to cause as much mischief as possible. Together, the group collects whatever food the townspeople offer: sacks of potatoes, bags of rice, or random vegetables. If the group is lucky, a family will toss them a live chicken to chase and cook. At the end of the day, the group retires to make a gumbo from their bounty and, hopefully, to dance to a good Cajun fiddler until the sun comes up.

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iStock // Ekaterina Minaeva
Man Buys Two Metric Tons of LEGO Bricks; Sorts Them Via Machine Learning
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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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Why Your iPhone Doesn't Always Show You the 'Decline Call' Button
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When you get an incoming call to your iPhone, the options that light up your screen aren't always the same. Sometimes you have the option to decline a call, and sometimes you only see a slider that allows you to answer, without an option to send the caller straight to voicemail. Why the difference?

A while back, Business Insider tracked down the answer to this conundrum of modern communication, and the answer turns out to be fairly simple.

If you get a call while your phone is locked, you’ll see the "slide to answer" button. In order to decline the call, you have to double-tap the power button on the top of the phone.

If your phone is unlocked, however, the screen that appears during an incoming call is different. You’ll see the two buttons, "accept" or "decline."

Either way, you get the options to set a reminder to call that person back or to immediately send them a text message. ("Dad, stop calling me at work, it’s 9 a.m.!")

[h/t Business Insider]