CLOSE
Original image
iStock

In Defense of Daylight Saving Time

Original image
iStock

This weekend, two things will happen. First, we’ll set our clocks forward one hour as we head into eight months of Daylight Saving Time (DST). Second, your social media news feed will fill up once again with lamentations about the switchover. There will be articles and essays denouncing DST as antiquated and unnecessary, and perhaps even harmful. What I find awkward about these rants is that, well-intentioned as they may be, they often fail to say what they’re arguing for.

WHY DO WE USE DAYLIGHT SAVING TIME IN THE FIRST PLACE?

Though Benjamin Franklin is often credited with the idea, the push for DST actually dates back only to the 1890s and first became law in Germany in 1916, in an effort to conserve coal during the First World War. In North America, DST was only widely adopted in the 1970s in response to the so-called energy crisis. Why the link to energy consumption? The theory is that people don’t switch on their lights until sunset, so if sunset can be pushed back, so to speak, we’ll use less energy. Another argument is that retailers benefit from pushing the clock back; people are more likely to go shopping when it’s light out. The extra summer sunlight also means more daylight hours for recreation, from golf to little league baseball to simply taking a stroll. 

But not so fast: The energy argument has always rested on inconclusive (and often contradictory) data, and anyway, energy-use patterns have changed over time. As the Washington Post recently noted: “More productive daylight hours might be meant to get you off the couch and recreating outside, but they’re just as likely to lead to increased air-conditioner use if you stay home and gas guzzling if you don’t.” (Indeed, a 2008 study suggested that energy use actually goes up slightly when DST is adopted.)

And then there’s DST’s alleged impact on human health: A 2011 University of Alabama study found that the switch to DST causes a 10 percent increase in the risk of heart attack. A 2007 German study found that the switch causes sleep disruption that the body never truly adjusts to, possibly increasing the susceptibility to illness. Last month, a study of nearly 15,000 people hospitalized in Finland found a small, temporary bump (8 percent) in the rate of stroke among those hospitalized in the first two days after a daylight saving time transition. There was no difference after two days.  

The cumulative case against DST was enough to get comedian John Oliver all worked up: In a 2015 viral video from Last Week Tonight, Oliver asked why DST is “still a thing.” (“What you lose in sleep, you gain in mortal danger,” the report noted dryly, referring to the purported health risks.)

What I find most striking about the opposition to DST is that it’s usually framed not as a preference for Standard Time, but as wanting to do away with the twice-a-year switch. (There’s a certain logic there, as the purported negative health effects are due to the switch, not to the actual time shown on our clocks.) That’s certainly the theme of the Oliver video, which makes no claim about wanting to keep Standard Time, or any other system, year-round.

But without DST, there really are only two options: Stay on Standard Time all year, or keep Daylight Time all year.

YEAR-ROUND STANDARD TIME VS. YEAR-ROUND DAYLIGHT SAVING TIME

But here’s the thing: If we stay on Standard Time year round, much of that extra summer daylight, divided equally between morning and evening, goes to waste. Do we really need four and a half hours of daylight before most of us start the work day, in June? Surely that light is more valuable to us in the evenings, when we’re finished work or school and (in theory, at least) can do as we please.

And so we’re tempted by the alternative argument: OK, Daylight Saving Time is good, but I hate the switch; let’s just stay on DST all year. But that, alas, leaves us with a lack of sunlight on winter mornings. We’d be driving to work in the dark, and our kids would be going to school in the dark. In the current system, sunrise in New York occurs at around 7:20 a.m. in late December (it’s about the same in San Francisco and Chicago; it’s 7:42 in Atlanta, which is further west within its time zone). Now imagine adding an hour to those times. Do we really want parts of the country to remain in darkness ’til 8:45 a.m. in mid-winter?

The diagram below sums up the problem: If you plot the amount of daylight that those of us living in mid-northern latitudes receive as a function of the time of the year, you get a big fat yellow bulge in the summer months, and a much thinner band of yellow for fall and winter.

SualehFatehi via Wikimedia Commons // Public Domain

As the diagram shows, DST has the effect of pushing the thickest part of that bulge downward, so that we have nice, late summer sunsets, while keeping the time of sunrise relatively constant throughout the year (yes, the time of sunrise still varies—but not by as much as it would if we stuck with Standard Time year-round).

Let’s face it: We can do what we like with our clocks; it doesn’t affect the amount of daylight that reaches us each day. The only question is when we’d like that daylight to happen. For those who rant against DST—and I’m sure we haven’t seen the last of them—all I ask is this: It’s not enough to say that you hate making the switch. You have to say what system you actually want.

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

Original image
Library of Congress
war
arrow
10 Facts About the Tomb of the Unknown Soldier
May 29, 2017
Original image
Library of Congress

On Veterans Day, 1921, President Warren G. Harding presided over an interment ceremony at Arlington National Cemetery for an unknown soldier who died during World War I. Since then, three more soldiers have been added to the Tomb of the Unknowns (also known as the Tomb of the Unknown Soldier) memorial—and one has been disinterred. Below, a few things you might not know about the historic site and the rituals that surround it.

1. THERE WERE FOUR UNKNOWN SOLDIER CANDIDATES FOR THE WWI CRYPT. 

Wikimedia Commons // Public Domain

To ensure a truly random selection, four unknown soldiers were exhumed from four different WWI American cemeteries in France. U.S. Army Sgt. Edward F. Younger, who was wounded in combat and received the Distinguished Service Medal, was chosen to select a soldier for burial at the Tomb of the Unknowns in Arlington. After the four identical caskets were lined up for his inspection, Younger chose the third casket from the left by placing a spray of white roses on it. The chosen soldier was transported to the U.S. on the USS Olympia, while the other three were reburied at Meuse Argonne American Cemetery in France.

2. SIMILARLY, TWO UNKNOWN SOLDIERS WERE SELECTED AS POTENTIAL REPRESENTATIVES OF WWII.

One had served in the European Theater and the other served in the Pacific Theater. The Navy’s only active-duty Medal of Honor recipient, Hospitalman 1st Class William R. Charette, chose one of the identical caskets to go on to Arlington. The other was given a burial at sea.

3. THERE WERE FOUR POTENTIAL KOREAN WAR REPRESENTATIVES.

WikimediaCommons // Public Domain

The soldiers were disinterred from the National Cemetery of the Pacific in Hawaii. This time, Army Master Sgt. Ned Lyle was the one to choose the casket. Along with the unknown soldier from WWII, the unknown Korean War soldier lay in the Capitol Rotunda from May 28 to May 30, 1958.

4. THE VIETNAM WAR UNKNOWN WAS SELECTED ON MAY 17, 1984.

Medal of Honor recipient U.S. Marine Corps Sgt. Maj. Allan Jay Kellogg, Jr., selected the Vietnam War representative during a ceremony at Pearl Harbor.

5. BUT THE VIETNAM VETERAN WASN'T UNKNOWN FOR LONG.

Wikipedia // Public Domain

Thanks to advances in mitochondrial DNA testing, scientists were eventually able to identify the remains of the Vietnam War soldier. On May 14, 1998, the remains were exhumed and tested, revealing the “unknown” soldier to be Air Force 1st Lt. Michael Joseph Blassie (pictured). Blassie was shot down near An Loc, Vietnam, in 1972. After his identification, Blassie’s family had him moved to Jefferson Barracks National Cemetery in St. Louis. Instead of adding another unknown soldier to the Vietnam War crypt, the crypt cover has been replaced with one bearing the inscription, “Honoring and Keeping Faith with America’s Missing Servicemen, 1958-1975.”

6. THE MARBLE SCULPTORS ARE RESPONSIBLE FOR MANY OTHER U.S. MONUMENTS. 

The Tomb was designed by architect Lorimer Rich and sculptor Thomas Hudson Jones, but the actual carving was done by the Piccirilli Brothers. Even if you don’t know them, you know their work: The brothers carved the 19-foot statue of Abraham Lincoln for the Lincoln Memorial, the lions outside of the New York Public Library, the Maine Monument in Central Park, the DuPont Circle Fountain in D.C., and much more.

7. THE TOMB HAS BEEN GUARDED 24/7 SINCE 1937. 

Tomb Guards come from the 3rd U.S. Infantry Regiment "The Old Guard". Serving the U.S. since 1784, the Old Guard is the oldest active infantry unit in the military. They keep watch over the memorial every minute of every day, including when the cemetery is closed and in inclement weather.

8. BECOMING A TOMB GUARD IS INCREDIBLY DIFFICULT.

Members of the Old Guard must apply for the position. If chosen, the applicant goes through an intense training period, in which they must pass tests on weapons, ceremonial steps, cadence, military bearing, uniform preparation, and orders. Although military members are known for their neat uniforms, it’s said that the Tomb Guards have the highest standards of them all. A knowledge test quizzes applicants on their memorization—including punctuation—of 35 pages on the history of the Tomb. Once they’re selected, Guards “walk the mat” in front of the Tomb for anywhere from 30 minutes to two hours, depending on the time of year and time of day. They work in 24-hour shifts, however, and when they aren’t walking the mat, they’re in the living quarters beneath it. This gives the sentinels time to complete training and prepare their uniforms, which can take up to eight hours.

9. THE HONOR IS ALSO INCREDIBLY RARE.

The Tomb Guard badge is the least awarded badge in the Army, and the second least awarded badge in the overall military. (The first is the astronaut badge.) Tomb Guards are held to the highest standards of behavior, and can have their badge taken away for any action on or off duty that could bring disrespect to the Tomb. And that’s for the entire lifetime of the Tomb Guard, even well after his or her guarding duty is over. For the record, it seems that Tomb Guards are rarely female—only three women have held the post.

10. THE STEPS THE GUARDS PERFORM HAVE SPECIFIC MEANING.

Everything the guards do is a series of 21, which alludes to the 21-gun salute. According to TombGuard.org:

The Sentinel does not execute an about face, rather they stop on the 21st step, then turn and face the Tomb for 21 seconds. They then turn to face back down the mat, change the weapon to the outside shoulder, mentally count off 21 seconds, then step off for another 21 step walk down the mat. They face the Tomb at each end of the 21 step walk for 21 seconds. The Sentinel then repeats this over and over until the Guard Change ceremony begins.

SECTIONS
BIG QUESTIONS
BIG QUESTIONS
WEATHER WATCH
BE THE CHANGE
JOB SECRETS
QUIZZES
WORLD WAR 1
SMART SHOPPING
STONES, BONES, & WRECKS
#TBT
THE PRESIDENTS
WORDS
RETROBITUARIES