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Comment Why exactly should I switch away from appear.in? (Score 1) 56

Let's see:
  • - Runs in a browser. A good one like Firefox or Chrome, not Explorer.
  • - Free
  • - Super simple to setup and just works. You sent the other side a link, they open it and the conference starts.
  • Just because it is Microsoft's tool doesn't make it my preferred tool. Actually, just the opposite.

Comment Switch tasks when you are stuck (Score 5, Interesting) 106

My 2 cents: When stuck at one problem it is of no use to focus. Better do something different, so your brain stops going in circles. However, when one task just flies along, stay with it to maximize your productivity. I try to have several tasks in parallel so I can switch between them if I am stuck at one. When I return after a while, I approach the problem from a new angle, which would not had happened when I had focused on the same task all along.

What is totally useless is to do several things in parallel. The old story of Napoleon being able to dictate a letter, read a book, have a conversation and lead a battle all at the same time is simply bullshit. Had he done so, he would had sucked at all of them, in parallel.

Comment Re:the only thing left (Score 1) 238

Wow, eve the aircraft knowledge here is bad!

While your Cessna needs to run its engine on a substantial fraction of its rated power (typically 60% or more), any decent car will only need low double digit kW to cruise. Comparing the rated power is utterly misleading, and your Tesla aircraft would drain its batteries and overheat the motor within minutes.

Comment Re:This will only be used on business jets, if at (Score 2, Interesting) 63

Where does the article even hint at wave drag disappearing at higher supersonic speed?

Wave drag is primarily and effect in the *transonic* from about M0.8 to 1.1 or 1.2, and then basically disappears at speeds above that.

Wrong. Why don't you do some basic fact-checking yourself before wrongly accusing others?

Comment most digital math is inherently imperfect (Score 1) 192

When using floating point math you always have an imprecise representation of the actual number. You might be lucky that the finite number of bits will be able to represent the intended number exactly, but when you start with analog values and convert them to digital, you always add noise.

This "new" technology sound as if they move from double precision back to single precision. Of course it needs less circuitry and power.

Comment Re:Bet you this is the key to real AI (Score 1) 192

Yeah, Marvin is a fictional character, but it's believable to me that true artificial intelligences will get bored, distracted, make mistakes, etc., just like people, making them perhaps not much better than people at many of the moderately mindless tasks we'd like them to take on. So we'll have to limit them to make them good at what we want them to do... which may make them not so good at what we want them to do.

You would need to implement emotions. Deep learning is still completely void of emotions, and that makes it better at what it does than humans.

Comment Re:More important than the sonic boom (Score 4, Informative) 63

Are modern engines as efficient at Mach 1.5 as they are at Mach 0.9?

No. The engine doesn't notice the speed, the intake takes care of that. But to create thrust, the exhaust flow must be faster than the intake flow, and making the exhaust flow faster lowers the overall efficiency of the engine. This is why subsonic engines have a high bypass ratio while for supersonic engines bypass ratio must be kept low.

Comment This will only be used on business jets, if at all (Score 4, Interesting) 63

Supersonic flight adds a new source of drag, called wave drag, which comes on top of all other drag. It depends on the slenderness of the plane, but can easily double the total amount of drag. Optimizing the design for less pronounced shock waves will increase drag yet again, so fuel consumption per mile flown will make the cost of supersonic travel prohibitive. After all, the travel speeds of modern airliners (Mach 0.78 to 0.855) is typically a bit lower than the design speed of early jet airliners like the Convair 990 (Mach 0.87) or the Vickers VC-10 (Mach 0.89). That was half a century ago!

But there is a pocket of aviation where progress has been made in flight speed: Business jets! While the first generation flew more slowly than airliners (Lockheed JetStar, Lear Jet 25), the latest designs are quite a bit faster (Cessna Citation X, Gulfstream V) at up to Mach 0.935. Why? There is a peeing contest going on among their owners who is the fastest. A very small segment of mankind is licking their fingers at a new chance for showing off. A supersonic business jet would be a sure sell to this crowd, even if the operating cost per mile doubles.

Well, see it this way: This is a chance for the other 99.9% of mankind to lower the Gini coefficient a bit.

Submission + - Berkeley Earth: 2015 Warmest Year on Record (berkeleyearth.org)

Titus Andronicus writes: According to a recent report from Berkeley Earth, 2015 was the warmest year in the instrumental temperature record, exceeding the prior record-holders 2014, 2010, and 2005 by roughly 0.1 deg C, or about 0.2 deg F. NASA, NOAA, the UK Met Office, and the Japan Meteorological Agency have yet to release their respective reports, but their findings are expected to be similar. 2016 might be even warmer, as the current El Nino event in the equatorial waters of the Pacific Ocean is expected to continue for several more months.

Submission + - Why Procrastination is Good for You

HughPickens.com writes: Over 80 percent of college students are plagued by procrastination, requiring epic all-nighters to finish papers and prepare for tests. Roughly 20 percent of adults report being chronic procrastinators. But Adam Grant writes in the NYT that while we think of procrastination as a curse for productivity, procrastination is really a virtue for creativity. According to Grant our first ideas are usually our most conventional but when you procrastinate, you’re more likely to let your mind wander giving you a better chance of stumbling onto the unusual and spotting unexpected patterns. "When we finish a project, we file it away. But when it’s in limbo, it stays active in our minds." Jihae Shin designed some experiments. She asked people to come up with new business ideas. Some were randomly assigned to start right away. Others were given five minutes to first play Minesweeper or Solitaire. Everyone submitted their ideas, and independent raters rated how original they were. The procrastinators’ ideas were 28 percent more creative. When people played games before being told about the task, there was no increase in creativity. It was only when they first learned about the task and then put it off that they considered more novel ideas. It turned out that procrastination encouraged divergent thinking.

Even some monumental achievements are helped by procrastination. Grant says that according to those who knew him, Steve Jobs procrastinated constantly, Bill Clinton has been described as a “chronic procrastinator” who waits until the last minute to revise his speeches, and Frank Lloyd Wright spent almost a year procrastinating on a commission, to the point that his patron drove out and insisted that he produce a drawing on the spot. It became Fallingwater, Wright's masterpiece. Aaron Sorkin, the screenwriter behind “Steve Jobs” and “The West Wing,” is known to put off writing until the last minute. When Katie Couric asked him about it, he replied, “You call it procrastination, I call it thinking.”

Submission + - Human Rights Watch Blasts TPP for "Serious Rights Concerns" (freezenet.ca)

Dangerous_Minds writes: Freezenet is reporting that Human Rights Watch, an international human rights organization, has blasted the TPP over what they call "serious rights concerns". Among the concerns are privacy rights as well as the implications the trade deal would have on free speech. Already, some are expecting all 12 countries to sign off on the TPP next month.

Further reading: Human Rights Watch press release and TPP Q & A.

Submission + - How fast do gravitational waves travel? 1

StartsWithABang writes: When Einstein’s theory was first proposed as an alternative to Newtonian gravity, there were a number of subtle but important theoretical differences noted between the two. Einstein’s theory predicted gravitational redshift, time delays, bending of light and more. But what was perhaps most remarkable is that unlike Newton’s gravity, Einstein’s general relativity predicted an entirely new phenomenon: gravitational radiation. Much like how charged particles moving in a magnetic field accelerate and emit radiation in the form of photons, masses moving in a gravitational field accelerate and emit radiation in the form of gravitational waves, or ripples in the fabric of space itself. Even though these waves move at c, the speed of light in a vacuum, the expanding Universe carries them even farther, as these ripples ride atop the fabric of our expanding spacetime.

Comment Happiness is relative (Score 5, Interesting) 729

Psychology studies show it's not the absolute material wealth that makes you happy and content but the relative, in comparison to others in your social group. That's why top executives have spiraled up their pay packages, and why the middle class never lowered their work time below what is filling your day.

When Volkswagen experimented with 4-workday weeks 20 years ago, local plumbers and carpenters fell on hard times because everyone now used the extra day to fix things themselves, or even work on the side on that extra day. While the unions keep telling you that workers would relax during the extra time resulting from reduced work, in reality everyone tries to make a little extra on the side.

Also, having a job gives meaning to your life. Being told that you will be needed less is like telling you that you are a burden - nobody wants to hear that. That is also why today both parents work, even though they could enjoy the standard of living of a single-earner household of 50 years ago. But to keep up with the Joneses and to feel better for themselves both are now working, and the downside of less parenting seems to be generally accepted.

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