Month: February 2017

Study reveals why so many met a sticky end in Boston’s Great Molasses Flood

In 1919, a tank holding 2.3m gallons of molasses burst, causing tragedy. Scientists now understand why the syrup tsunami was so deadly

It may sound like the fantastical plot of a childrens story but Bostons Great Molasses Flood was one of the most destructive and sombre events in the citys history.

On 15 January 1919, a muffled roar heard by residents was the only indication that an industrial-sized tank of syrup had burst open, unleashing a tsunami of sugary liquid through the North End district near the citys docks.

As the 15-foot (5-metre) wave swept through at around 35mph (56km/h), buildings were wrecked, wagons toppled, 21 people were left dead and about 150 were injured.

Now scientists have revisited the incident, providing new insights into why the physical properties of molasses proved so deadly.

Presenting the findings last weekend at the American Association for the Advancement of Science annual meeting in Boston, they said a key factor was that the viscosity of molasses increases dramatically as it cools.

This meant that the roughly 2.3m US gallons of molasses (8.7m litres) became more difficult to escape from as the evening drew in.

Speaking at the conference, Nicole Sharp, an aerospace engineer and author of the blog Fuck Yeah Fluid Dynamics said: The sun started going down and the rescue workers were still struggling to get to people and rescue them. At the same time the molasses is getting harder and harder to move through, its getting harder and harder for people who are in the wreckage to keep their heads clear so they can keep breathing.

As the lake of syrup slowly dispersed, victims were left like gnats in amber, awaiting their cold, grisly death. One man, trapped in the rubble of a collapsed fire station, succumbed when he simply became too tired to sweep the molasses away from his face one last time.

Its horrible in that the more tired they get its getting colder and literally more difficult for them to move the molasses, said Sharp.

Leading up to the disaster, there had been a cold snap in Boston and temperatures were as low as -16C (3F). The steel tank in the harbour, which had been built half as thick as model specifications, had already been showing signs of strain.

Two days before the disaster the tank was about 70% full, when a fresh shipment of warm molasses arrived from the Caribbean and the tank was filled to the top.

One of the things people described would happen whenever they had a new molasses shipment was that the tank would rumble and groan, said Sharp. People described being unnerved by the noises the tank would make after it got filled.

Ominously, the tank had also been leaking, which the company responded to by painting the tank brown.

There were a lot of bad signs in this, said Sharp.

Sharp, and a team of scientists at Harvard University, performed experiments in a large refrigerator to model how corn syrup (standing in for molasses) behaves as temperature varies, confirming contemporary accounts of the disaster.

Historical estimates said that the initial wave would have moved at 56km/h [35mph], said Sharp. When we take models … and then we put in the parameters for molasses, we get numbers that are on a par with that. Horses werent able to run away from it. Horses and people and everything were all caught up in it.

The giant molasses wave follows the physical laws of a phenomenon known as a gravity current, in which a dense fluid expands mostly horizontally into a less dense fluid. Its what lava flows are, its what avalanches are, its that awful draught that comes underneath your door in the wintertime, said Sharp.

The team used a geophysical model, developed by Professor Herbert Huppert of the University of Cambridge, whose work focuses on gravity currents in processes such as lava flows and shifting Antarctic ice sheets.

The model suggests that the molasses incident would have followed three main stages.

The current first goes through a so-called slumping regime, said Huppert, outlining how the molasses would have lurched out of the tank in a giant looming mass.

Then theres a regime where inertia plays a major role, he said. In this stage, the volume of fluid released is the most important factor determining how rapidly the front of the wave sweeps forward.

Then the viscous regime generally follows, he concluded. This is what dictates how slowly the fluid spreads out and explains the grim consequences of the Boston disaster.

It made a difference in how difficult it would be to rescue people and how difficult it would be to survive until you were rescued, said Sharp.

Read more: https://www.theguardian.com/science/2017/feb/25/study-reveals-why-so-many-met-a-sticky-end-in-bostons-great-molasses-flood

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The Map Of Mathematics

If you want to up your nerd-level, just watch this video by Dominic Walliman about the different fields of math. But beware: Over 350,000 people already have seen this and might be a lot smarter by now. Try to keep up!

“The entire field of mathematics summarised in a single map! This shows how pure mathematics and applied mathematics relate to each other and all of the sub-topics they are made from.”

via: sploid

Read more: https://www.viralviralvideos.com/2017/02/10/the-map-of-mathematics/

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Cassie” Is Set To Revolutionize The Way Robots Walk

Robots can prevent heart failures, diagnosis cancers, and evenbeat a website’sI Am Not A Robottest. But on the whole, they really do suck at walking.

Hopefully, Cassie willbe able to change that. Looking like a mix between a chicken and an AT-ST Walker from Star Wars, this bipedal machine was developed by Agility Robotics, a robotics startup born out of Oregon State University.

Cassie was createdwith a 16-month, $1 million grant from the Defense Advanced Research Projects Agency (DARPA). Building on the work of Oregon States ATRIAS robot, this sleeker design is able to walk over uneven surfaces, cope with different elevations, and even deal with a kick from a human (see video below).

Rather interestingly, Cassie wasnt explicitly designed to look like an ostrich fromthe get-go. Instead, its simply the way their mathematics dictated the most stable and agile two-legged moving structure.

“We werent trying to duplicate the appearance of an animal, just the techniques it uses to be agile, efficient and robust in its movement, Jonathan Hurst, an associate professor of robotics in the OSU College of Engineering, said in astatement.

Revolutionizing robot mobility in this way could open the door for a limitless number of applications by allowing robots to go anywhere people can go. This could mean anything from delivering parcels, walking the dog, exploring dangerous territories, or even fighting wars.

Quite simply, robots with legs can go a lot of places that wheels cannot. This will be the key to deliveries that can be made 24 hours a day, 365 days a year, by a fleet of autonomous vans that pull up to your curb, and an onboard robot that delivers to your doorstep, Hurst added.This technology will simply explode at some point, when we create vehicles so automated and robots so efficient that deliveries and shipments are almost free.

Read more: http://www.iflscience.com/technology/cassie-is-set-to-revolutionize-the-way-robots-walk/

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This Light Painting, Double Pendulum Elegantly Demonstrates Chaotic Movement

Pendulus” is a double pendulum built by Devin Montes that visualizes the unpredictable patterns of chaotic movement in real-time, using an LED light and glow-in-the-dark paint.

For more cool projects, check out Devin’s YouTube channel, Make Anything // 3D Printing Channel

Read more: http://twistedsifter.com/videos/light-painting-double-pendulum-visualizes-chaotic-movement/

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U.S. Public Schools Are Not Failing. Theyre Among The Best In The World

Everyone knows U.S. public schools are failing.

Just like everyone knows you should never wake sleepwalkers, bulls hate red and Napoleon was short.

Wrong on all counts. Waking sleepwalkers will cause them no harm in fact, theyre more likely to harm themselves while sleepwalking. Bulls are colorblind; theyre attracted to movement. And Napoleon was 57, which was above average height for Frenchman during his lifetime.

So why do we believe that American public schools are doing such a terrible job?

Because far-right policymakers have convinced us all that its true.

Its not.

Let me repeat that in no uncertain terms Americas public schools are NOT failing. They are among the best in the world. Really!

We have made a commitment to every single child regardless of what their parents can afford to pay, regardless of their access to transportation, regardless of whether they can afford uniforms, lunch or even if they have a home. Heck! We even provide education to children who are here illegally.

That cant be said of many countries with which were often compared especially countries comparable to the U.S. in size or diversity. So from the get-go, we have an advantage over most of the world.

We define education differently. Though our laws are woefully backward, in practice we look at it as a right, not a privilege. And for a full 13 years (counting kindergarten) its a right for every child, not just some.

But thats not all! We also provide some of the highest quality education you can get in the world! We teach more, help more, achieve more and yet we are criticized more than any system in any country in the world.

TEST SCORES

Critics argue that our scores on international tests dont justify such a claim. But theyre wrong before you even look at the numbers. Theyre comparing apples to pears. You simply cant compare the United States to countries that leave hundreds of thousands of rural and poor children without any education whatsoever. The Bates Motel may have the softest pillows in town, but its immediately disqualified because of the high chance of being murdered in the shower.

No school system of this size anywhere in the world exceeds the United States in providing free access to education for everyone. And that, alone, makes us one of the best.

It doesnt mean our system is problem free. There are plenty of ways we could improve. Were still incredibly segregated by race and class. Our funding formulas are often regressive and inadequate. Schools serving mostly poor students dont have nearly the resources of those serving rich students. But at least at the very outset what were trying to do is better than what most of the world takes on. You cant achieve equity if it isnt even on the menu.

However, for some people, this will not be enough. Theyll say that despite our high ideals, the quality of what we actually provide our students is low. After all, those international test scores are so low.

First point: it depends on the scores youre looking at. American elementary and middle school students have improved on theTrends in International Mathematics and Science Study every four years since the tests began in 1995. They are above the international average in all categories and within a few percentage points of the global leaders (something rarely mentioned on the nightly news).

Even on the PISA test administered by the Organization for Economic Cooperation and Development to 15-year-olds in about 60 countries, US children are far from the bottom of the scale. Were somewhere in the middle. Weve always been in the middle for all the decades since theyve been making these comparisons. Our schools have not gotten worse. They have stayed the same.

IDEALS AND POVERTY

To some this just demonstrates that our schools have always been mediocre. But again youre overlooking the consequences of our ideals.

The broader the spectrum of children who take a test, the lower the average score will be. In other words, if only your top students take the test, your average score will be very high. If only your top and middle students take the test, your average score will still be quite high. But if ALL of your students take the test, your average score will be lower.

Now add in poverty. Living in poverty reduces your access to health care, books, early childhood education and many other factors that increase learning throughout your life. Children from poor families are already more than a year behind those of rich parents on the first day of kindergarten. If you only test the wealthiest students, the average test score will probably be quite high. The average score will drop dramatically if you test all of your students.

Thats why many of these countries where the poorest children do not have access to education have higher test scores than the United States. Youre not comparing equals. The United States has the highest child poverty rate in the Western World. And we dont hide them away. We include them on our tests. That has a major impact on our scores. But talking heads on TV almost always ignore it. They pretend it doesnt exist. Its the only way they can use these test scores to prove to a gullible audience that Americas schools are failing.

But if you fairly compare education systems and factor in the equal access we provide for all children to an education, our system comes out way on top. We have one of the best systems in the world.

But wait! Theres more!

SPECIAL EDUCATION

Not only does the United States serve all children regardless of academic achievement or poverty. We also serve far more students with disabilities.

Why are there so many special education children in the USA? Because we have a higher standard of living.

A standard pregnancy lasts about 280 days or 40 weeks. However, some mothers give birth to children after only 28 weeks. Two decades ago, these babies would not have survived. Today, they often do. Five years later that child will enter kindergarten and our school system will be responsible for teaching that student to read, write and learn math. In other countries, premature babies have a much lower chance of survival. They dont survive to become the special education population. So things as diverse as the live-birth rate actually affect average test scores.

Another counterintuitive factor is the suicide rate. In many countries where pressure to perform at the highest levels on standardized tests is extreme, many children are actually driven to suicide. This is especially true in numerous Asian countries with a record of high scores on these international tests. So a higher suicide rate actually increases test scores.

Would you say this makes other countries superior to the United States? Heck no! In fact, just the opposite. I certainly wouldnt wish more underperforming U.S. students were ending their lives so we could do better on international tests. Nor would I wish that more premature babies died to improve our international standing.

We have developed a special education system to help children at the edges that many other countries just cant touch. In some countries these students are simply excluded. In others they are institutionalized. In some countries its up to parents to find ways to pay for special services. The United States is one of the only countries where these children are not only included and offered full and free access, but the schools go above and beyond to teach these children well beyond their 12th academic year.

In every public school in the United States these students are included. In math, reading, science and social studies, they are there benefiting from instruction with the rest of the class. And this, in turn, benefits even our non-special education students who gain lessons in empathy and experience the full range of human abilities.

Of course, most of our special education students are also included in our test scores. Yes, other countries that ignore these children and exclude them from testing get higher scores. But so what? Do you mean to tell me this makes them better? No, it makes them worse.

In many ways, we are the gold standard, not them. They should be emulating us, not the other way around. They should be jealous of the way we prize each others humanity. We shouldnt be salivating at test scores achieved through shunning certain students in favor of others.

CURRICULUM AND STRATIFICATION

But its not just who we teach, its also what we teach.

Compared to many other countries, U.S. school curriculum is often much wider and varied. Countries that focus only on testing often leave out sciences, arts, literature and humanities.

Unfortunately, the push from policymakers even in the U.S. has been to narrow curriculum to imitate some of the worst practices of our competitors. But in many districts we still strive to create well-rounded graduates and not just good test-takers.

The bottom line: the curriculum at most American schools is more inclusive than that found internationally. We even include societal issues like alcohol and drug abuse prevention, stress reduction and relaxation, and physical fitness programs.

In addition we dont stratify our children based on academic ability to nearly the same degree as many international schools. We dont weed out our worst students through middle and high school until only our most capable are left in 12th grade. Nor is college only open to our best and brightest. We make a much greater effort than many other countries to keep this option open to as many students as possible regardless of whether they can afford it or not. The number of Americans with at least some college educationhas soared over the past 70 years, from 10 percent in 1940 to 56 percent today, even as the population has tripled and the nation has grown vastly more diverse. Meanwhile, Graduation rates are at an all-time high of 83.2 percent, and for the first time minority students are catching up with their white counterparts.

Its not easy. But its something were committed to as a nation. And thats not true around the world.

SIZE MATTERS

Finally, theres the issue of size. The United States is a big country the third most populous in the world. We have 324,450,000 people and growing. Thats about 50 million students in public schools.

Its much easier to educate less children. Even excellent education systems would struggle with our sheer numbers. Small systems often outshine bigger ones. For instance, I might be able to make dinner for my immediate family, but Id find it much more challenging to prepare a meal for a banquet hall of hundreds. Similarly, it remains to be seen whether smaller nations could handle educating a population as big and diverse as ours without collapsing.

By any fair measure, Americas public education system is simply stunning. But the media perpetuates the myth that were failing.

PUBLIC PERCEPTION AND THE MEDIA

After decades of hearing these falsehoods, the American public is strikingly divided. On a 2011 Gallup poll, parents were asked their opinion of their local school and the public was asked its opinion of schools in general. The results are enlightening. Parents who gave their local school an A grade were at the highest percentage ever (37%) whereas only 1% of respondents rated the nations schools that way. Why the difference? Respondents said it was mostly because people knew about their local schools through direct experience. They only learned about the state of education nationally through the news media.

Why is education reporting so biased? Part of it is monetary. Huge corporations make hundreds of millions of dollars off of the failing schools narrative. They sell new standardized tests, new test prep materials, new Common Core books, trainings for teachers, materials, etc. If they cant demonstrate that our schools are failing, their market shrinks. And who do you think owns the shrinking media conglomerates? Thats right, many of these same corporations.

But even when journalists want to be fair, its difficult for them to get the inside story of how our public schools work. They are rarely permitted inside our schools to see the day-to-day classroom experience. Legal issues about which students may be photographed, filmed or interviewed, the difficulty of getting parental permissions and the possibility of embarrassment to principals and administrators often keeps the doors closed. In many districts, teachers arent even allowed to speak on the record to the media or doing so can make them a political target. So reporters are often in the position of being unable to directly experience the very thing theyre reporting on. Imagine if sportswriters never got to see athletes play or political reporters never attended a campaign rally. Of course there would be a disconnect!

So were left with a public education system that should be the envy of the world being portrayed as a loser.

THE BOTTOM LINE

As ever, far-right politicians on both sides of the aisle, whether they be Democratic Neoliberals or Republican Tea Partiers, are using falsehoods about our public schools to sell an alternative. They say our public schools are beyond saving and that we need to privatize. They call it school choice but its really just an attempt to destroy the system that has so much going for it.

We should strengthen public education not undermine it. We should roll up our sleeves and fix the real problems we have, not invent fake ones.

People act as if alternative facts were invented by the Trump administration. Our policymakers have been using them for decades in a libelous and dishonest campaign against our public schools.

They are some of the best in the world if only people knew it.

***

This article originally appeared on my Website, Gadfly on the Wall Blog.

Read more: http://www.huffingtonpost.com/entry/us-public-schools-are-not-failing-theyre-among_us_5894e819e4b061551b3dfe51?ncid=inblnkushpmg00000009

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In a post-truth world, statistics could provide an essential public service | John Pullinger

Statisticians can now amass more data more quickly than ever. This could help us to make decisions based on real numbers, not prejudice

In the post-truth society there is a huge opportunity for statistics. On the face of it that may sound like a contradiction. But as individuals trying to work out what is really going on in the world around us, for businesses trying to decide on their next venture, and for governments trying to form effective policy, there is a common desire: data.

There is great potential for us to mobilise the power of data to help us make better decisions. However, the technology that has allowed us all to be so wonderfully connected has also allowed us each to live in our own world, separated from others. In our online lives, we risk connecting only with those with similar views to our own and not encountering those who think differently something many commentators are now terming the social media echo chamber.

But this is not new we have always tended to mix with people of similar backgrounds, and inevitably we have tended to read those newspapers whose outlook we prefer. However, what is different, is that for many people, especially the young, looking to the web rather than broadcast bulletins, this risk is growing. In this situation, it becomes increasingly hard to understand how anyone else can have a different view. It also becomes increasingly easy to think little of those who do.

This can make us prey to those who choose to support their own perspective with facts that show just how right they are (and how wrong everyone else). These facts can be made up. They can be biased or out of context. Often they fit the old adage about the drunk and the lamppost used more for support than illumination. This wilful blindness is dangerous.

Of course decisions are made on the basis of emotions and beliefs as well as science. Those of us who work in the world of data need some humility in what we claim. But good evidence does matter. Anyone who wants us to succeed as individuals, families, communities, businesses and as a country should stand up and make the case.

Unless we have a trustworthy understanding of where we are now, unless we can analyse what works, and unless we can focus attention on what matters, we are unlikely to make the most of the opportunities we must now seize in the months and years ahead.

My current job as a government statistical adviser was first created by Winston Churchill in 1941 when he said, with uncharacteristic understatement, that the utmost confusion is caused when people base arguments on different numbers. He called for someone to provide information that could be accepted and used without question. That remains a powerful rallying call for me and my colleagues.

And today, while the data revolution has created a moment of danger, it also provides the opportunity to gain new insights. It is now possible to get those insights much more quickly, in more fine-grained forms, and to design them to illuminate the issues that people care about. Recent reports produced by my team on domestic violence, our ageing population and UK productivity are just some examples of what is possible. With the right rules in place to respect the fact that we make use of information about individuals and individual businesses and must not betray their privacy, there is an unprecedented potential to use data to serve the public good.

So, with the supply of data increasing rapidly, perhaps our real challenge is to take our statistics off the page and find ways to listen and connect with those people who have been left perplexed and disappointed by experts. For us in official statistics, as well as the wider statistical world, that means our mission has to shift fundamentally, from being mere producers of numbers to providers of an essential public service. That way we can realise the potential that now exists to help us all make better decisions.

Read more: https://www.theguardian.com/commentisfree/2017/jan/31/post-truth-statistics-data-facts

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