But regarding their testing, it was certainly a small scale test of known technology, but you underestimate the value of such tests. There's massive amounts of theoretical aspects they have to plow through first, move gradually to small scale live tests and finally piece it all together in one big PoC. After the small pieces are theorized and tested, it takes exponentially less time to piece them all together in the end.
I wouldn't say I underestimate the value of small-scale tests so much as I would say that Musk and company have been deliberately obscure about exactly what they were testing, and have been downright misleading about the distance between where they are now and what they claim they will be able to deliver. We were shown a dog-and-pony show constructed to meet an artificial publicity deadline, not a well-explained demonstration as part of a clearly-elucidated development roadmap.
When I read comments like yours, it reminds me of anti-innovation corporate voices I have to battle against on a daily basis.
Hmm. Do you misrepresent your progress and conceal the nature of your accomplishments to your corporate masters too, then? That could be your problem.
Look, I'm a scientist in an academic setting, but with private-sector collaborators. I do both "pure" and "applied" research. I contribute to both peer-reviewed papers and patent applications. I can tell the difference between healthy skepticism and blind anti-innovation. The problem with Musk's Hyperloop demo isn't the idea, or the technology, or the dream--it's that he doesn't tell us what the demo is actually doing. It's like writing a scientific paper that starts with the usual Abstract and Introduction, then jumps straight to a one-liner Conclusion and a big Discussion about the implications of the work and all the cool stuff that's going to happen in the future. He just skipped over the Materials & Methods and the detailed Results. We aren't told what we're actually looking at or what it can really do, just to take on faith that it's awesome. That's my issue.
The "first successful test" appears to have been a small test sled on a short, low-speed test track. Yes, they showed they could drive a piece of metal with a linear induction motor, but that's just demonstrating an application of known technology. Vancouver's SkyTrain has been using linear induction propulsion since 1985 as part of a regular, boring, functional public transit system. Similar technology appears in Toronto (the Scarborough Rapid Transit line), New York (the AirTrain JFK airport link), and at least a handful of other sites.
Practically speaking, one could have done the same demo by taking a 30-year-old SkyTrain car, stripping the body and seats out, and flipping the induction drive unit sideways to be compatible with the vertically-mounted induction track shown on the Hyperloop demo system. (You'd get great acceleration, too, since you can dump much of the car's weight--and you wouldn't care about the components surviving for more than a few seconds of photo op.) Maybe there were major technological advances under the hood, but the breathless hype all glosses over any meaningful description of what might have been accomplished.
A large-scale pure-science project. A tool that will advance modern astrophysical and astronomical research. A landmark technical achievement.
But it came from funny-looking furriners (not just funny-talking, like them ones from Yurp). So we must be sure to cast the headline in the most derisive terms possible. It's not a research tool that shoestring SETI projects will be able to snag a bit of time on--no, it's an "alien-hunting telescope".
I mean, my God--snippets of Aricebo's time have been used for alien-hunting (and alien-spamming) for decades. It was used to send publicity stunt messages to M13 in 1974, and to some nearer stars in 2009. SETI@home users have been crunching Aricebo data looking for little green men since 1999. And yet, oddly enough, no one ever seems to refer to Aricebo as an "alien-hunting telescope". Why is that?
You'd rather break someone else's bones than total a car where everyone escapes injury free? That's messed up.
Heck, it probably even falls down (er...) on a strict monetary cost basis. A broken bone caused by a vehicle colliding with a pedestrian likely has a bunch of associated soft tissue injury, which can lead to all kinds of expensive-to-manage (and -treat) damage. The straight-up hospital bills plus lost wages for pedestrian victim can very easily pile up to more than the insured value of a car--making those priorities a net loss for society even if we assign no value at all to preventing pain and suffering.
Of course, it's also silly to pretend that the car is "smart" enough to confidently and reliably predict what will be a moderate injury versus a potentially-fatal one. The car doesn't know if a wound is going to suffer a serious infection. The car doesn't know if a bone fragment is going to sever a major artery. The car doesn't know if the pedestrian will suffer a serious brain injury when her head hits the pavement. Pretending there's a firm choice between totalling the car and non-permanent injury is a fiction--the choice is between totalling the car and a risk of serious or fatal injury.
Our hearts go out to all those who are affected by the tragic shooting in Orlando. The Red Cross has received a tremendous outpouring of support and we are grateful for all who have responded. The blood needs from this tragedy have been met. In the event of an emergency, it’s the blood already on the shelves that can help save lives. That’s why it’s important that eligible individuals schedule an appointment to give blood and platelets in the weeks and months ahead.
Emphasis added. Don't take it from me, take it from the Red Cross.
"Posts directing people where and how to give blood have been removed."
While straight-up removal of such posts may not be the best approach, the intent behind such removals is likely honorable.
Donated blood needs to be screened for infectious diseases and otherwise processed before it can be used; it generally takes at least a couple of days before blood from a donor's arm can get to a patient's bedside. The blood that helps the victims of the Orlando massacre isn't the stuff that the Red Cross collects today and tomorrow; it's the blood that was donated last week or the week before. And blood has a limited shelf life--creating a big oversupply now doesn't help unless there's an enormous disaster in the next few weeks.
Donating blood now might make the donor feel good about themselves, but it's not actually a particularly constructive thing to do. If you want to help, put a reminder in your calendar to donate blood in two or three weeks, after this glut has made its way through the system. Or donate blood when the Red Cross (or whichever agency handles blood products in your jurisdiction) indicates a shortage. Better yet, get in the habit of donating blood regularly--help maintain a stable blood supply over the long term.
I'm sure that George Miller, Brendan McCarthy, and Nick Lathouris (winners, Ray Bradbury Award for Outstanding Dramatic Presentation) would be surprised to hear you say that.
No they wouldn't be surprised at all. They wrote a movie featuring strong women that was very popular with feminists. They know this is why they got to be the tokens this year.
So you're shifting the goalposts, then? It has to be men writing about men only. Got it.
(And I'm not sure why, even with your special pleading, you think you can ignore the inconvenient fact that men were amply represented among the nominees.)
I'm sure that George Miller, Brendan McCarthy, and Nick Lathouris (winners, Ray Bradbury Award for Outstanding Dramatic Presentation) would be surprised to hear you say that.
Or, for that matter, Charles Gannon, Ken Liu, Lawrence Schoen (Best Novel nominees); Eugene Fischer, Usman Malik (Novella nominees); Michael Bishop, Henry Lien (Novelette); David Levine, Sam Miller, Martin Shoemaker (Short Story)....
But since you can't read more than four lines into a Slashdot blurb, I suppose it isn't surprising that you don't know much about good writing.
It's important to note that by 'arousal', the researchers do not mean sexual arousal.
Though it should be noted that "arousing" only indicates a generally heightened state of awareness or attention.
Indeed, I was about to offer the same note. I presume that the quote from the article (and the paper's title) were deliberately offered without context in order to sound more titillating than they really are.
"Arousal" in this context can also represent nervousness, discomfort, fear,, and reluctance. The sensor is measuring skin conductance (galvanic skin response), which just indicates that there is increased blood flow and/or perspiration.
Soap doesn't kill germs. All it does is makes oily substances more likely to be pulled along by water than they were before.
Soap certainly kills some germs. There are lots of bacteria and viruses which are vulnerable to the SDS (sodium dodecyl sulfate), a detergent widely used in hand soaps, shampoos, and a bunch of other sudsy consumer products. The detergent disrupts the cell membranes of many bacteria, and it denatures (unfolds) important proteins in many strains of viruses and bacteria.
Sure, the improvements to mechanical cleaning and suspension of oily matter are important, too. And there are certainly some things (spores and other more robust pathogens) which are resistant to SDS and other detergents, particularly at short exposure times. But "soap doesn't kill every germ" is a long way from "soap doesn't kill germs".
I have to admit that when I first read the headline, my mind processed it as
Exploitable Backhoe Accidentally...
I figured that some nitwit had decided that large construction machinery needed to be part of the Internet of Things, and that the expected outcome had come to pass.
I'm totally with you on the lack of naked-eye night-sky access and I definitely don't want to minimize the loss it represents to city-dwelling humanity. I live in a large city way down at the bottom of the Bortle scale, in the center of one of those whited-out you-can't-see-a-thing patches on the light pollution maps. From time to time I'm lucky enough to get away to a little cabin in the woods with impeccable dark skies, but the rest of the time I have to make do with viewing from the parking lot next to my apartment building.
That said - and the article mentions this, but it's worth reiterating - a surprising amount of the sky becomes accessible again for those of us with even basic digital SLRs (and even some of the more fully-featured point-and-shoots). Last January, the nominally-naked-eye comet Lovejoy (C/2014 Q2) was in the sky near the Pleiades. No hope of seeing it with my own eyes, but it was an easy target for just about any lens in my camera bag. It's trivial to capture stars down below ninth magnitude There's a little bit of - a different sort of - magic to being able to pull so much of the night sky out of the muck.
I could probably do some moderately impressive things with binoculars, too, but I'm a bit concerned about what the neighbors would think.
Incidentally, the suggested camera settings provided in the CBC article (ISO 1600, 30 second exposure) may be a bit aggressive for very bright city skies, and will definitely show at least some star trailing. Don't be afraid to play around. My skies start to get too bright if I go beyond ISO 800, f/3.5, 5 s or equivalent. And a five-second exposure is close to the limit if you want to avoid perceptible star trails at a medium-wide focal length.
If it's parabolic but really really long, "near-hyperbolic" would be a reasonable description -- that's not out of the ordinary for comets.
Presumably it means that its orbit is closed - elliptical - but is only very loosely gravitationally bound--perhaps even more so that most comets. In other words, its velocity is only just shy of escape velocity, hence near-parabolic. Yes, mathematically speaking, that means that its orbit must also be near-hyperbolic; an infinitesimal increase in velocity converts a parabolic path into a hyperbolic one (and an infinitesimal decrease in velocity converts a parabolic path into a long-period ellipse).
No it's not.
Weight energy and volumic energy are two different things.
The article does not say which is which.
It's a good thing that the summary (didn't even have to click through to the article) indicates that it's using volumetric energy density for both:
"Sony is developing a new type of battery chemistry that can boost runtimes by 40 percent compared to lithium-ion batteries of the same volume. Sony's batteries use a sulfur compound instead of lithium compounds for the positive electrodes, reportedly allowing for much great energy density. Sulfur batteries can also supposedly be made 30 percent smaller than traditional lithium-ion cells while maintaining the same run times."
Weight - and therefore energy density per unit mass - isn't mentioned or implied.
The grandparent's observation is spot on--the summary is indeed saying exactly the same thing in two different ways. If you can have the same runtime in 30% less volume, you can always get 40% more runtime with the original-sized package. To within a trivial rounding error, 140% and 70% are reciprocals; they're just saying "40% improvement in volumetric energy density".
Just for clarification from TFA, they did not disqualify over 1,000 candidates. What they found was: 67 Binary Stars and 3 Brown Dwarfs out of the 129 candidates they actually looked at.
That seems like an awfully small sample size to me, but hey I'm not a scientist.
Actually, if that represents a random selection from their initial pool of candidates - that is, if they didn't do any initial pre-sorting to enrich their selection for stars over planets - then that's a reasonable sample size. As long as their sample was random, it's actually the absolute number of stars in their sample that matters. The standard deviation in their estimate of the number of non-planets goes as roughly the square root of the number of non-planets in the sample. We'll say the square root of 67 is about 8, so there's an estimated error of plus-or-minus 8 out of 129--about 6%.
If, before an election, you do a telephone survey of 1000 people, you'll be able to estimate the election's outcome with about the same confidence whether the country has a hundred thousand or a hundred million voters. Essentially the same statistical principle.
If that sounds weird, try it with inanimate objects instead. If I pull 100 jelly beans from a large and well-shaken bag, and 50 happen to be red, then I'm going to be pretty confident that roughly half of all the jelly beans are red--no matter how big the bag is. If I pull a 100 planet candidates from the Kepler survey and 50 turn out to be stars, then I'm going to be pretty confident that roughly half of the planet candidates are stars--no matter how big the list of Kepler candidates is.
If 40% of those university graduates are still overqualified by their mid-thirties, they've already been typecast by their experience in the 25-35 range.
That's certainly a problem with the data provided--it bundles together the fresh-out-of-school 25-year-olds with the decade-plus-in-the-workforce 34-year-olds. There's a lack of resolution. It could be that 40% of 25-year-olds and 40% of 34-year-olds are "overqualified". Or it could be that 60% in the 25-29 age group are overqualified, and just 20% of the 30-34 bracket.
Actually, that brings to mind another confounder to the interpretation of these data. As more young people get more years of formal education (3-year college diploma to 4- or 5-year bachelor's degree to 7-year bachelor-plus-master's degree) they enter the workforce later. A 25-year-old with a high school diploma might have been working for 7 years (and is also more likely to be working in a job for which they are not "overqualified" by their lower level of formal educational attainment). A 25-year-old with a master's degree might have graduated this summer and could still be job-hunting.
... an increasing number of university graduates are overqualified for their jobs.... 40 per cent of university graduates aged 25-34 were overqualified for their job.... The problem is bigger than that, because those young workers spent money, time, and resources to get those qualifications.
It could be a problem, but we're missing some information. This is looking at people aged 25-34. A lot of them are taking crappy entry-level jobs. A lot of them don't have any significant work experience, and have trouble breaking into their preferred fields. A lot of them have student loans and other financial obligations, and just need to take a job - any job - to keep food on the table and a roof overhead. (That, in itself, is another kettle of problems that I'm not going to go into right now.)
An important question is, then, how many of them are still overqualified by the time they're into the 35-44 age bracket? Was the extra education actually "wasted", or did they eventually come out ahead because they didn't have to drop out of the workforce later on to go back to school to get the education they missed in their twenties? Did their extra "unnecessary" knowledge help them move up the ladder faster than they would have without it? (I'm not looking for anecdotes - of which I am sure there exist examples to suit any preferred narrative - but rather real data.)
And that leaves aside the rather more philosophical question of whether or not it's generally a Good Thing to have more university-educated individuals in it, even if they don't need those degrees specifically as job training. Are universities now only vocational schools, and only of value to society in that context? If I can't cash in my degree for a high-paying job, is it worthless?
...but then the stupidity of taking off at less than 100% throttle to save a little bit of fuel at the expense of increasing risk is also a pretty dumb thing to do, engineering wise.
Taking off at less than 100% throttle means reduced acceleration, which reduces stress on the airframe (and passengers). It reduces wear on the engines and - more important - reduces the risk of turbine failure. It makes the aircraft easier to control (less unbalanced thrust) if it does lose an engine immediately before or after takeoff.
There is no diffraction...20,000 miles is nothing. A laser beam that measures several microns wide at it's origin will still be several microns wide at it's destination.
This is fundamentally incorrect. Even under ideal conditions laser beams will diverge in proportion to their wavelength and in inverse proportion to their narrowest diameter. Effectively, the laser light interferes with itself - diffracts - as it passes through the aperture from which it emerges. At visible or near-infrared wavelengths, a "collimated" 10-micron-wide beam will be more than 30 meters across at 1 km from its source. (I confess to doing the math in my head, but the order of magnitude is about right.) At 20,000 miles, the beam will be more than 100 km across. Wikipedia has the formulas if you'd like to play with them: beam divergence.
You can improve performance by increasing aperture (beam diameter) and wavelength, but there are limits. Beam divergence gets a hell of a lot better with a 1-centimeter (or 1-meter) rather than a 10-micron beam, but also puts about one millionth (or one ten-billionth) as much power down per unit of area on the target.
This isn't to say that space-based anti-satellite lasers aren't possible, but your assumptions about the behavior and performance of lasers over long ranges (and the associated technical challenges) are not grounded in adequate physics knowledge. The Soviets took a stab at launching an anti-satellite laser weapon back in 1987. Polyus weighed 80 tons, required a massive booster, used a 1-megawatt carbon dioxide laser, and was still only intended for low-orbit targets. (And suffered a launch failure, but that's not important.)
If I remember correctly, the noise floor of the previous instrument was approximately the level of the signal they were looking for.
A better detector may help.
Indeed. It's hard to overstate the sensitivity of these instruments, or the vulnerability of these instruments to noise. To take one example, here's an ArXiv preprint that calculates that the original LIGO detectors would need to be physically shielded from tumbleweeds, since the the impact of a wind-borne tumbleweed on the building exterior (100 feet from the detector) could produce a vibrational or gravitational transient sufficient to appear to be a spurious gravitational wave signal.
Neither the summary nor the linked article provide the necessary statistics to tell us how well this algorithm actually works. We're told it has a 68% success rate, which presumably means that 68% of the time it gives the same answer as de Vries (the human subject/programmer).
The problem is, we're not told anything about the sensitivity or specificity of the technique. What is the rate of false positives? False negatives?
Let's say that de Vries typically finds 1 out of 3 (33%) of the profile pictures "attractive". His computer could score 67% accuracy just by rejecting every single picture. (Such an algorithm would have zero sensitivity, but perfect specificity, and a terrible false negative rate. The "reject-everything" algorithm also scores better the more picky de Vries gets.)
This sort of story is only interesting if it includes specific information about where and how his algorithm fails (and succeeds).
Slashdot Mirror
But regarding their testing, it was certainly a small scale test of known technology, but you underestimate the value of such tests. There's massive amounts of theoretical aspects they have to plow through first, move gradually to small scale live tests and finally piece it all together in one big PoC. After the small pieces are theorized and tested, it takes exponentially less time to piece them all together in the end.
I wouldn't say I underestimate the value of small-scale tests so much as I would say that Musk and company have been deliberately obscure about exactly what they were testing, and have been downright misleading about the distance between where they are now and what they claim they will be able to deliver. We were shown a dog-and-pony show constructed to meet an artificial publicity deadline, not a well-explained demonstration as part of a clearly-elucidated development roadmap.
When I read comments like yours, it reminds me of anti-innovation corporate voices I have to battle against on a daily basis.
Hmm. Do you misrepresent your progress and conceal the nature of your accomplishments to your corporate masters too, then? That could be your problem.
Look, I'm a scientist in an academic setting, but with private-sector collaborators. I do both "pure" and "applied" research. I contribute to both peer-reviewed papers and patent applications. I can tell the difference between healthy skepticism and blind anti-innovation. The problem with Musk's Hyperloop demo isn't the idea, or the technology, or the dream--it's that he doesn't tell us what the demo is actually doing. It's like writing a scientific paper that starts with the usual Abstract and Introduction, then jumps straight to a one-liner Conclusion and a big Discussion about the implications of the work and all the cool stuff that's going to happen in the future. He just skipped over the Materials & Methods and the detailed Results. We aren't told what we're actually looking at or what it can really do, just to take on faith that it's awesome. That's my issue.
Mod parent up.
The "first successful test" appears to have been a small test sled on a short, low-speed test track. Yes, they showed they could drive a piece of metal with a linear induction motor, but that's just demonstrating an application of known technology. Vancouver's SkyTrain has been using linear induction propulsion since 1985 as part of a regular, boring, functional public transit system. Similar technology appears in Toronto (the Scarborough Rapid Transit line), New York (the AirTrain JFK airport link), and at least a handful of other sites.
Practically speaking, one could have done the same demo by taking a 30-year-old SkyTrain car, stripping the body and seats out, and flipping the induction drive unit sideways to be compatible with the vertically-mounted induction track shown on the Hyperloop demo system. (You'd get great acceleration, too, since you can dump much of the car's weight--and you wouldn't care about the components surviving for more than a few seconds of photo op.) Maybe there were major technological advances under the hood, but the breathless hype all glosses over any meaningful description of what might have been accomplished.
"Alien-hunting telescope"? Really, guys?
A large-scale pure-science project. A tool that will advance modern astrophysical and astronomical research. A landmark technical achievement.
But it came from funny-looking furriners (not just funny-talking, like them ones from Yurp). So we must be sure to cast the headline in the most derisive terms possible. It's not a research tool that shoestring SETI projects will be able to snag a bit of time on--no, it's an "alien-hunting telescope".
I mean, my God--snippets of Aricebo's time have been used for alien-hunting (and alien-spamming) for decades. It was used to send publicity stunt messages to M13 in 1974, and to some nearer stars in 2009. SETI@home users have been crunching Aricebo data looking for little green men since 1999. And yet, oddly enough, no one ever seems to refer to Aricebo as an "alien-hunting telescope". Why is that?
You'd rather break someone else's bones than total a car where everyone escapes injury free? That's messed up.
Heck, it probably even falls down (er...) on a strict monetary cost basis. A broken bone caused by a vehicle colliding with a pedestrian likely has a bunch of associated soft tissue injury, which can lead to all kinds of expensive-to-manage (and -treat) damage. The straight-up hospital bills plus lost wages for pedestrian victim can very easily pile up to more than the insured value of a car--making those priorities a net loss for society even if we assign no value at all to preventing pain and suffering.
Of course, it's also silly to pretend that the car is "smart" enough to confidently and reliably predict what will be a moderate injury versus a potentially-fatal one. The car doesn't know if a wound is going to suffer a serious infection. The car doesn't know if a bone fragment is going to sever a major artery. The car doesn't know if the pedestrian will suffer a serious brain injury when her head hits the pavement. Pretending there's a firm choice between totalling the car and non-permanent injury is a fiction--the choice is between totalling the car and a risk of serious or fatal injury.
There's a lot of dumb posts on this story, but this one makes my top 5.
I'll just quote the front page of the American Red Cross' website:
Our hearts go out to all those who are affected by the tragic shooting in Orlando. The Red Cross has received a tremendous outpouring of support and we are grateful for all who have responded. The blood needs from this tragedy have been met. In the event of an emergency, it’s the blood already on the shelves that can help save lives. That’s why it’s important that eligible individuals schedule an appointment to give blood and platelets in the weeks and months ahead.
Emphasis added. Don't take it from me, take it from the Red Cross.
"Posts directing people where and how to give blood have been removed."
While straight-up removal of such posts may not be the best approach, the intent behind such removals is likely honorable.
Donated blood needs to be screened for infectious diseases and otherwise processed before it can be used; it generally takes at least a couple of days before blood from a donor's arm can get to a patient's bedside. The blood that helps the victims of the Orlando massacre isn't the stuff that the Red Cross collects today and tomorrow; it's the blood that was donated last week or the week before. And blood has a limited shelf life--creating a big oversupply now doesn't help unless there's an enormous disaster in the next few weeks.
Donating blood now might make the donor feel good about themselves, but it's not actually a particularly constructive thing to do. If you want to help, put a reminder in your calendar to donate blood in two or three weeks, after this glut has made its way through the system. Or donate blood when the Red Cross (or whichever agency handles blood products in your jurisdiction) indicates a shortage. Better yet, get in the habit of donating blood regularly--help maintain a stable blood supply over the long term.
I guess no men wrote anything decent this year?
I'm sure that George Miller, Brendan McCarthy, and Nick Lathouris (winners, Ray Bradbury Award for Outstanding Dramatic Presentation) would be surprised to hear you say that.
No they wouldn't be surprised at all. They wrote a movie featuring strong women that was very popular with feminists. They know this is why they got to be the tokens this year.
So you're shifting the goalposts, then? It has to be men writing about men only. Got it.
(And I'm not sure why, even with your special pleading, you think you can ignore the inconvenient fact that men were amply represented among the nominees.)
What the difference between Novel, Novella, Novelette and Short Story? I guess all them translate to the same thing for me.
Length. Short story is less than 7,500 words, Novelette is 7,500-15,000 words, Novella is 15,000-40,000 words, and Novel is 40,000 words and up.
I guess no men wrote anything decent this year?
I'm sure that George Miller, Brendan McCarthy, and Nick Lathouris (winners, Ray Bradbury Award for Outstanding Dramatic Presentation) would be surprised to hear you say that.
Or, for that matter, Charles Gannon, Ken Liu, Lawrence Schoen (Best Novel nominees); Eugene Fischer, Usman Malik (Novella nominees); Michael Bishop, Henry Lien (Novelette); David Levine, Sam Miller, Martin Shoemaker (Short Story)....
But since you can't read more than four lines into a Slashdot blurb, I suppose it isn't surprising that you don't know much about good writing.
It's important to note that by 'arousal', the researchers do not mean sexual arousal.
Indeed, I was about to offer the same note. I presume that the quote from the article (and the paper's title) were deliberately offered without context in order to sound more titillating than they really are.
"Arousal" in this context can also represent nervousness, discomfort, fear,, and reluctance. The sensor is measuring skin conductance (galvanic skin response), which just indicates that there is increased blood flow and/or perspiration.
Every prime is odd, so there are no prime number that end in 0 in base 2.
10 is prime.
Soap doesn't kill germs. All it does is makes oily substances more likely to be pulled along by water than they were before.
Soap certainly kills some germs. There are lots of bacteria and viruses which are vulnerable to the SDS (sodium dodecyl sulfate), a detergent widely used in hand soaps, shampoos, and a bunch of other sudsy consumer products. The detergent disrupts the cell membranes of many bacteria, and it denatures (unfolds) important proteins in many strains of viruses and bacteria.
Sure, the improvements to mechanical cleaning and suspension of oily matter are important, too. And there are certainly some things (spores and other more robust pathogens) which are resistant to SDS and other detergents, particularly at short exposure times. But "soap doesn't kill every germ" is a long way from "soap doesn't kill germs".
This is the outcome of the government's 2016 budget which imposes huge savings on research and education.
You seem to have misspelled "cuts".
I have to admit that when I first read the headline, my mind processed it as
Exploitable Backhoe Accidentally...
I figured that some nitwit had decided that large construction machinery needed to be part of the Internet of Things, and that the expected outcome had come to pass.
The excuse "Medical privacy" when it comes to a wild animal is really causing the person using it to look like a fool.
The person who rejected the FOIA request 'signed' his name in Comic Sans. This is not a person who is concerned about looking like a fool.
I'm totally with you on the lack of naked-eye night-sky access and I definitely don't want to minimize the loss it represents to city-dwelling humanity. I live in a large city way down at the bottom of the Bortle scale, in the center of one of those whited-out you-can't-see-a-thing patches on the light pollution maps. From time to time I'm lucky enough to get away to a little cabin in the woods with impeccable dark skies, but the rest of the time I have to make do with viewing from the parking lot next to my apartment building.
That said - and the article mentions this, but it's worth reiterating - a surprising amount of the sky becomes accessible again for those of us with even basic digital SLRs (and even some of the more fully-featured point-and-shoots). Last January, the nominally-naked-eye comet Lovejoy (C/2014 Q2) was in the sky near the Pleiades. No hope of seeing it with my own eyes, but it was an easy target for just about any lens in my camera bag. It's trivial to capture stars down below ninth magnitude There's a little bit of - a different sort of - magic to being able to pull so much of the night sky out of the muck.
I could probably do some moderately impressive things with binoculars, too, but I'm a bit concerned about what the neighbors would think.
Incidentally, the suggested camera settings provided in the CBC article (ISO 1600, 30 second exposure) may be a bit aggressive for very bright city skies, and will definitely show at least some star trailing. Don't be afraid to play around. My skies start to get too bright if I go beyond ISO 800, f/3.5, 5 s or equivalent. And a five-second exposure is close to the limit if you want to avoid perceptible star trails at a medium-wide focal length.
What the hell does that mean?
If it's parabolic but really really long, "near-hyperbolic" would be a reasonable description -- that's not out of the ordinary for comets.
Presumably it means that its orbit is closed - elliptical - but is only very loosely gravitationally bound--perhaps even more so that most comets. In other words, its velocity is only just shy of escape velocity, hence near-parabolic. Yes, mathematically speaking, that means that its orbit must also be near-hyperbolic; an infinitesimal increase in velocity converts a parabolic path into a hyperbolic one (and an infinitesimal decrease in velocity converts a parabolic path into a long-period ellipse).
No it's not. Weight energy and volumic energy are two different things. The article does not say which is which.
It's a good thing that the summary (didn't even have to click through to the article) indicates that it's using volumetric energy density for both:
"Sony is developing a new type of battery chemistry that can boost runtimes by 40 percent compared to lithium-ion batteries of the same volume. Sony's batteries use a sulfur compound instead of lithium compounds for the positive electrodes, reportedly allowing for much great energy density. Sulfur batteries can also supposedly be made 30 percent smaller than traditional lithium-ion cells while maintaining the same run times."
Weight - and therefore energy density per unit mass - isn't mentioned or implied.
The grandparent's observation is spot on--the summary is indeed saying exactly the same thing in two different ways. If you can have the same runtime in 30% less volume, you can always get 40% more runtime with the original-sized package. To within a trivial rounding error, 140% and 70% are reciprocals; they're just saying "40% improvement in volumetric energy density".
Just for clarification from TFA, they did not disqualify over 1,000 candidates. What they found was: 67 Binary Stars and 3 Brown Dwarfs out of the 129 candidates they actually looked at.
That seems like an awfully small sample size to me, but hey I'm not a scientist.
Actually, if that represents a random selection from their initial pool of candidates - that is, if they didn't do any initial pre-sorting to enrich their selection for stars over planets - then that's a reasonable sample size. As long as their sample was random, it's actually the absolute number of stars in their sample that matters. The standard deviation in their estimate of the number of non-planets goes as roughly the square root of the number of non-planets in the sample. We'll say the square root of 67 is about 8, so there's an estimated error of plus-or-minus 8 out of 129--about 6%.
If, before an election, you do a telephone survey of 1000 people, you'll be able to estimate the election's outcome with about the same confidence whether the country has a hundred thousand or a hundred million voters. Essentially the same statistical principle.
If that sounds weird, try it with inanimate objects instead. If I pull 100 jelly beans from a large and well-shaken bag, and 50 happen to be red, then I'm going to be pretty confident that roughly half of all the jelly beans are red--no matter how big the bag is. If I pull a 100 planet candidates from the Kepler survey and 50 turn out to be stars, then I'm going to be pretty confident that roughly half of the planet candidates are stars--no matter how big the list of Kepler candidates is.
If 40% of those university graduates are still overqualified by their mid-thirties, they've already been typecast by their experience in the 25-35 range.
That's certainly a problem with the data provided--it bundles together the fresh-out-of-school 25-year-olds with the decade-plus-in-the-workforce 34-year-olds. There's a lack of resolution. It could be that 40% of 25-year-olds and 40% of 34-year-olds are "overqualified". Or it could be that 60% in the 25-29 age group are overqualified, and just 20% of the 30-34 bracket.
Actually, that brings to mind another confounder to the interpretation of these data. As more young people get more years of formal education (3-year college diploma to 4- or 5-year bachelor's degree to 7-year bachelor-plus-master's degree) they enter the workforce later. A 25-year-old with a high school diploma might have been working for 7 years (and is also more likely to be working in a job for which they are not "overqualified" by their lower level of formal educational attainment). A 25-year-old with a master's degree might have graduated this summer and could still be job-hunting.
... an increasing number of university graduates are overqualified for their jobs.... 40 per cent of university graduates aged 25-34 were overqualified for their job.... The problem is bigger than that, because those young workers spent money, time, and resources to get those qualifications.
It could be a problem, but we're missing some information. This is looking at people aged 25-34. A lot of them are taking crappy entry-level jobs. A lot of them don't have any significant work experience, and have trouble breaking into their preferred fields. A lot of them have student loans and other financial obligations, and just need to take a job - any job - to keep food on the table and a roof overhead. (That, in itself, is another kettle of problems that I'm not going to go into right now.)
An important question is, then, how many of them are still overqualified by the time they're into the 35-44 age bracket? Was the extra education actually "wasted", or did they eventually come out ahead because they didn't have to drop out of the workforce later on to go back to school to get the education they missed in their twenties? Did their extra "unnecessary" knowledge help them move up the ladder faster than they would have without it? (I'm not looking for anecdotes - of which I am sure there exist examples to suit any preferred narrative - but rather real data.)
And that leaves aside the rather more philosophical question of whether or not it's generally a Good Thing to have more university-educated individuals in it, even if they don't need those degrees specifically as job training. Are universities now only vocational schools, and only of value to society in that context? If I can't cash in my degree for a high-paying job, is it worthless?
...but then the stupidity of taking off at less than 100% throttle to save a little bit of fuel at the expense of increasing risk is also a pretty dumb thing to do, engineering wise.
Taking off at less than 100% throttle means reduced acceleration, which reduces stress on the airframe (and passengers). It reduces wear on the engines and - more important - reduces the risk of turbine failure. It makes the aircraft easier to control (less unbalanced thrust) if it does lose an engine immediately before or after takeoff.
So...not just to save fuel.
There is no diffraction...20,000 miles is nothing. A laser beam that measures several microns wide at it's origin will still be several microns wide at it's destination.
This is fundamentally incorrect. Even under ideal conditions laser beams will diverge in proportion to their wavelength and in inverse proportion to their narrowest diameter. Effectively, the laser light interferes with itself - diffracts - as it passes through the aperture from which it emerges. At visible or near-infrared wavelengths, a "collimated" 10-micron-wide beam will be more than 30 meters across at 1 km from its source. (I confess to doing the math in my head, but the order of magnitude is about right.) At 20,000 miles, the beam will be more than 100 km across. Wikipedia has the formulas if you'd like to play with them: beam divergence.
You can improve performance by increasing aperture (beam diameter) and wavelength, but there are limits. Beam divergence gets a hell of a lot better with a 1-centimeter (or 1-meter) rather than a 10-micron beam, but also puts about one millionth (or one ten-billionth) as much power down per unit of area on the target.
This isn't to say that space-based anti-satellite lasers aren't possible, but your assumptions about the behavior and performance of lasers over long ranges (and the associated technical challenges) are not grounded in adequate physics knowledge. The Soviets took a stab at launching an anti-satellite laser weapon back in 1987. Polyus weighed 80 tons, required a massive booster, used a 1-megawatt carbon dioxide laser, and was still only intended for low-orbit targets. (And suffered a launch failure, but that's not important.)
If I remember correctly, the noise floor of the previous instrument was approximately the level of the signal they were looking for. A better detector may help.
Indeed. It's hard to overstate the sensitivity of these instruments, or the vulnerability of these instruments to noise. To take one example, here's an ArXiv preprint that calculates that the original LIGO detectors would need to be physically shielded from tumbleweeds, since the the impact of a wind-borne tumbleweed on the building exterior (100 feet from the detector) could produce a vibrational or gravitational transient sufficient to appear to be a spurious gravitational wave signal.
Neither the summary nor the linked article provide the necessary statistics to tell us how well this algorithm actually works. We're told it has a 68% success rate, which presumably means that 68% of the time it gives the same answer as de Vries (the human subject/programmer).
The problem is, we're not told anything about the sensitivity or specificity of the technique. What is the rate of false positives? False negatives?
Let's say that de Vries typically finds 1 out of 3 (33%) of the profile pictures "attractive". His computer could score 67% accuracy just by rejecting every single picture. (Such an algorithm would have zero sensitivity, but perfect specificity, and a terrible false negative rate. The "reject-everything" algorithm also scores better the more picky de Vries gets.)
This sort of story is only interesting if it includes specific information about where and how his algorithm fails (and succeeds).