It doesn't work that way. [...] There has to be corroborating evidence.
Ask Kavanaugh how that worked out. He wasn't convicted of anything, but without a single bit of corroborating evidence, his name was smeared to high hell and back and his career stained forever. Accusation without corroborating evidence can still be very damaging.
Considering he now has a lifetime appointment to the Supreme Court, I'd say it worked out pretty well. You sound like the President: oh woe is Kavanaugh, you poor thing! He is now (if he wasn't already) is a fine position to not give two shits about what other people think about him.
I think he'll be just fine.
And you're right: he wasn't convicted of anything. On the other hand, he wasn't undergoing a criminal trial, facing jail time or other harsh penalties. He was being considered for a very, very important job that, ultimately, stems from the trust the American people put in the Court. Untold number of people have been denied jobs (even, or especially, high-profile jobs) for far, far less than a single person's sworn testimony.
Let us call it a "snark". After all, scientists tend to come up with whimsical names when they run out of rational alternatives. For example: after coining "proton", "neutron" and "electron", physicists moved on to "quark" as an obscure reference to a James Joyce novel, followed by the "up", "down", "strange", "charm", "bottom" and "top" monikers, which are even more nonsense.
"Snark" has a similar whimsical literary pedigree. It was the titular character in a Lewis Carroll poem - a creature that was hunted, but was itself indescribable. "Snark" was also the name of a character in a sci-fi novel: an extra-terrestrial intelligence, like the Clarke's Monolith, watching for developing intelligence in our solar system. More to the point, the snark in that novel spent some time orbiting our own Moon
It's expected to cost a couple $billion more to finish developing the BFR, although once it's done it's also expected to be cheaper to launch than a Falcon Heavy. It being more powerful seems like a poor excuse when it's also cheaper.
It is worth noting that, so far anyway, the BFR has only ever been shown as a launcher for the BFS - a human carrier with re-entry and landing capabilities. We haven't ever seen a cargo-only upper stage for the BFR - something that could deploy satellites. It's like comparing a C-5 cargo jet to an Airbus A380 passenger jet. The latter is not a substitute for the former: it's just not an appropriate match.
That said, I do not doubt that SpaceX could make a cargo-deploying upper stage for BFR - one that can re-enter and land, too, probably. But we haven't seen that yet.
I'd say in this case they are totally at odds with one another, and politics is winning. Is there any less economical way to get people into space than SLS?
Actually, yes, death by carbon monoxide poisoning would be preferrable to carbon dioxide.
In the former case, you get drowsy, fall asleep, and eventually asphyxiate. CO binds to hemoglobin, preventing your blood from taking up oxygen. You die of hypoxia, which is generally thought of being pretty painless. (If hypoxia were painful, then high-altitude mountaineering would be impossible, rather than just merely hard.) A similar death would occur in a depressurized airline cabin if you don't put your mask on. CO poisoning happens to a 100s of people each year in the U.S. due to faulty heating systems. One reason deaths result is because people aren't aware that it's even happening - they just fall asleep, then die. This is why your home should have at least one CO detector per floor.
Carbon dioxide poisoning, on the other hand, is definitely a rough way to go. Hold your breath for a while and you'll see what I mean. That panic you're feeling, the tightening of the chest, the burning, that's caused by your brainstem realizing your blood has built up too much CO2. At low levels, high CO2 concentration in the air will make your irritable, give you a headache, and generally make it hard to function at your best. (Astronaut Scott Kelly complained about this a lot during his year on the ISS.) Taken higher, and your entire body becomes acidotic, and that feeling of drowning becomes all-encompassing. Eventually, your metabolism will break down at a cellular level as your blood becomes saturated with CO2. You'll have passed out long before that, but your last conscious moments will probably be in agony.
Is everyone supposed to look up everything online now, even in places where there is no internet connection?
Yes. That is what you are supposed to do. What is the point of a printed manual for a whiz-bang piece of tech like an Android phone or $2000-$5000 laptop when there is no internet connection? Maybe such tech is still useful without the connection, but that is a tiny minority of use cases. That tiny minority does not justify the expense of preparing, printing, and distributing manuals.
A more common use case would be this: a manufacturer goes through the expense of preparing, printing, and distributing manuals with their product. Then, after all that effort, 75% of end users never even open it. Of those that do open it, most will never reference it later on. A tiny fraction of users will reference several times during the life of the device. Some users will look at the printed manual, puzzle over the table of contents, and wonder where all the hyperlinks are. What, no search tool?
Another thing to consider is currency: hardware and software changes often, and probably as soon as the manual was prepared and published, some of the information in it would be dated, misleading, incorrect, or otherwise out-of-sync with reality. Keeping a soft copy up-to-date (like an online support page) is much easier.
Data centers in the U.S. alone eat up 70 billion kilowatts of energy per year, according to a 2016 estimate from the Department of Energy -- that's 1.8 percent of all energy use across the country
Goddammit! I see this conflation of energy in power in the mainstream press all the feakin' time. Kilowatts is not a unit of energy! It's a unit of power (energy consumption over time). If a reporter doesn't know the difference, and doesn't realize that the different is really important, then I can't trust that any of the rest of their reporting is worth my time.
However, since they couldn't be bothered to do even a modicum of technical checking, I will help fill in the blanks. There are two ways to interpret this statement:
They are actually talking about power, in which case "energy per year" is not logical
Data centers in the U.S. alone eat up 70 billion kilowatts of power, according to a 2016 estimate from the Department of Energy -- that's 1.8 percent of all power use across the country
or, they are actually talking about energy, in which case the unit should be kilowatt-hours
Data centers in the U.S. alone eat up 70 billion kilowatt-hours of energy per year, according to a 2016 estimate from the Department of Energy -- that's 1.8 percent of all energy use across the country
In the first case, they would be talking about 70 terawatts of power, and that being 1.8% of the US consumption. This is absurd: the average energy consumption of the U.S. is only a few terawatts.
In the second case, they would be talking about 70 terawatt-hours of energy, implying a total consumption in the U.S.of about 3888 TWh. This is in line with recent statistics for U.S.electricity consumption. However, electricity consumption is not the same as total energy consumption, where one also has to consider energy for heating, transportation, industrial processes, etc.
So, the reporter is talking about energy, not power. He or she doesn't know the correct units, and conflates electrical consumption with total energy consumption. In short, the reporter is sloppy as all get out with their information. No wonder we can't have a proper debate about energy in this country - no one knows what the hell they're talking about.
Elon took their word and ended up in the mess. He was naive babe in the woods to these wolves.
What got Elon in trouble wasn't trusting the Saudis. His mistake was running his mouth off on twitter, and his overarching desire to stick it to the shorts.
If it's medical: I live in a first world country. I will not go into debt over medical issues.
Ah! You must not be living in the United States, then. Around here, even people with medical insurance routinely go into debt and bankruptcy over medical issues.
Average age of a car in America is 11.5 years and generally only the higher end cars have these features anyway. This is a first world problem for the top 10-20%.
These kinds of higher-end features have a way of making it down into less expensive models over time. Hell, many of them, like airbags and ABS, have become mandated equipment. So being aware of this as a problem, even a "first world problem" now, and understanding how to mitigate it, will become more important over time.
It is already happening. My in-laws replaced both their cars recently, and specifically looked for these features. They ended up with a Honda Accord and a Rav4, which are most definitely not "higher end cars". (They did have to buy the higher trim levels in order to get these features.) This is becoming mainstream.
Not only does it use a fossil fuel to obtain the H2 and require energy to run the process, it also ends up getting LESS energy out of the gas itself than if the gas had just been burnt directly
You have to be careful about comparing energy here, though. If you want to compare total energy output (i.e., heat) then, yes, the hydrogen is worse than the natural gas.
But the metric we care about is natural gas input to mechanical work output. In one scenario, you have a natural gas-powered locomotive (do those even exist?), which will be limited to the Carnot efficiency of whatever heat engine you are using to burn the gas and get mechanical work (30%, maybe). Actually, it's probably worse than that, because the locomotive probably can't be directly powered by that heat engine - the range of torque and speed needed at different operating conditions is a terrible match for a gas turbine. Instead, most locomotives (including conventional diesels) burn fuel to run a generator, then have an electric powertrain for the wheels. So there is a further conversion step that will incur an efficiency hit. In all, you might be lucky to get 20% of the natural gas' original potential energy converted into mechanical work.
In the other scenario, you convert the natural gas to H2, then send that through a fuel cell to get electricity, then move the locomotive by an electric motor. The fuel cell is not limited by Carnot efficiency, and the electric --> work conversion in the electric motor has quite high efficiency (85%-95%). I do not have numbers in front of me, but I suspect that you'll find the hydrogen-fueled system gets more mechanical work from the natural gas input than just burning it in an engine.
zero-emissions source of fuel my ass. You still need to isolate and enrich the H2, which takes energy.. We need to consider total emissions for KJ output.
Your point is valid - most hydrogen is produced by steam reformation of natural gas, which releases CO2. Widescale production of hydrogen without substantial emissions (e.g., electrolysis powered by wind and solar) is still a long ways off
On the other hand, that doesn't mean that it's totally incorrect to refer to hydrogen as "zero emissions." There aren't any emissions from the release of that energy. That is, unlike a diesel locomotive, there are no tailpipe emissions. A pedant would say "well, then, they should clarify and say 'zero tailpipe emissions'", and they would be correct. But emissions from diesel locomotives - and other diesel emissions like trucks and container ships, are sources of substantial air pollution that is a hazard to human health. So switching to hydrogen still has benefits.
And, since you were curious about emissions per kJ output... I suggest having a look at this paper from 2014, comparing the total emissions of a gasoline car to a hydrogen fuel cell equivalent. It's not quite the same comparison as locomotives, but gets the point across. Per distance traveled, the fuel cell vehicle produces 34% fewer CO2 emissions per distance traveled if the hydrogen is sourced from natural gas. As the hydrogen source greens (i.e., electrolysis replaces steam reformation), the emissions drop further.
It never made sense to me why you want to have a wireless charger that needs plugged in that delivers less power less efficiently than just plugging the wire into the phone and skipping a step.
In this case, there were two reasons: 1) we wanted a 100% sealed case, no ports or anything, and 2) our target audience was the disabled community, who may not have the dexterity (or, in some cases, any hands at all) to make a cabled connection.
I won't be so bold as to crow "Oh, they should have seen this coming." Still, this should not be a surprise, as anyone who has used wireless charging has experienced.
I worked on a product some years ago that was using a competitor to the Qi standard. Our product had a receiver coil that captured the alternating magnetic field, rectified it, and delivered that bulk power to the Li-Ion charge circuit. Worked great, except when you realize that the entire device is immersed in this alternating magnetic field. Every conductor, and in particular every ferromagnetic component (screws, the metal housing of the Li-Ion cell, a metallic portion of the housing, everything) was heating up due to eddy currents. As a stopgap we ended up sticking a ferrite shield over the mat, to isolate only that area where we wanted the charge power to emit. That worked to limit the heating, mostly. But that made it not all that different from most wireless charging cradles before and since, where you have to align the product to the charger. Needing that alignment drastically reduced the utility of the wireless charging, which was one reason why we scrapped it.
Oh, and while we were delivering about 2 W of charge power to the Li-Ion battery, the mat was drawing about 18 W from the wall. Even when the device wasn't present and not charging, the mat drew 10 W. This experience has made me highly skeptical of the prospect of widespread wireless charging anytime soon.
The watch generally is processing a lot of floating point data as well so the extra accuracy may be helpful there.
It may also not be about increased precision. It is pretty common in floating-point architectures to allow a 64-bit FPU to perform operations on two 32-bit operands in parallel in the same amount of time. So instead of doing a 64-bit x 64-bit multiplication in some number of clock cycles, it can do two (32-bit x 32-bit) multiplications in the same time. A lot of that can be handled by compiler optimization, too, so that the programmer doesn't even need to plan for it.
The thing is, lifetime of a BEC is so short (last I heard, on the order of a few seconds), that itself puts significant constraints on precision measurements you can do.
It's worse than that - most BECs have a lifetime of fractions of a second. One of the limiting factors on the lifetime of a BEC is, oddly enough, gravity: the clump of particles simply falls out of the trap. A recent delivery to the International Space Station will allow for the creation of BECs with longer lifetimes: 5-10 seconds according to this article. That may still not sound like a lot, but it is an order of magnitude longer, and will allow deeper investigation of these tricky things. The better they are understood, the more likely useful applications may come along.
It is a recurring myth that corporations are somehow absolutely required by law to seek profit....This CEO is avoiding the legal implication by claiming it's a "moral" requirement.
In defense of NASA, this was an idea floated by a political appointee. I highly doubt this is something being pushed by the NASA rank and file. I suspect their reaction is the same as yours and mine.
But in the meantime, NASA is still doing exploration and useful science. They launched the Parker solar probe just a few weeks ago. People are still living on the International Space Station. We have a nuclear-powered rover on Mars that was delivered by a rocket skycrane. On New Years's Day, the New Horizons probe will fly past a Kuiper Belt Object - a spec so tiny they needed teams of telescopesin remote places just to confirm where it's orbit is. And then there's NASA's ongoing development of commercial crew vehicles. SpaceX and Boeing are, naturally, doing the bulk of the work, but NASA has a lot of say in the design and certification. NASA also happens to be the customer. And, oh yeah, when those capsules launch, they'll be crewed by NASA astronauts.
Slashdot Mirror
F#@k everything, we're doing five!
This is my Moon.
There are many like it, but this one is mine.
Well played, sir.
(or madam)
Considering he now has a lifetime appointment to the Supreme Court, I'd say it worked out pretty well. You sound like the President: oh woe is Kavanaugh, you poor thing! He is now (if he wasn't already) is a fine position to not give two shits about what other people think about him. I think he'll be just fine.
And you're right: he wasn't convicted of anything. On the other hand, he wasn't undergoing a criminal trial, facing jail time or other harsh penalties. He was being considered for a very, very important job that, ultimately, stems from the trust the American people put in the Court. Untold number of people have been denied jobs (even, or especially, high-profile jobs) for far, far less than a single person's sworn testimony.
Let us call it a "snark". After all, scientists tend to come up with whimsical names when they run out of rational alternatives. For example: after coining "proton", "neutron" and "electron", physicists moved on to "quark" as an obscure reference to a James Joyce novel, followed by the "up", "down", "strange", "charm", "bottom" and "top" monikers, which are even more nonsense.
"Snark" has a similar whimsical literary pedigree. It was the titular character in a Lewis Carroll poem - a creature that was hunted, but was itself indescribable. "Snark" was also the name of a character in a sci-fi novel: an extra-terrestrial intelligence, like the Clarke's Monolith, watching for developing intelligence in our solar system. More to the point, the snark in that novel spent some time orbiting our own Moon
I doubt it: the NRO does not like to share.
It is worth noting that, so far anyway, the BFR has only ever been shown as a launcher for the BFS - a human carrier with re-entry and landing capabilities. We haven't ever seen a cargo-only upper stage for the BFR - something that could deploy satellites. It's like comparing a C-5 cargo jet to an Airbus A380 passenger jet. The latter is not a substitute for the former: it's just not an appropriate match.
That said, I do not doubt that SpaceX could make a cargo-deploying upper stage for BFR - one that can re-enter and land, too, probably. But we haven't seen that yet.
I'd say in this case they are totally at odds with one another, and politics is winning. Is there any less economical way to get people into space than SLS?
Actually, yes, death by carbon monoxide poisoning would be preferrable to carbon dioxide.
In the former case, you get drowsy, fall asleep, and eventually asphyxiate. CO binds to hemoglobin, preventing your blood from taking up oxygen. You die of hypoxia, which is generally thought of being pretty painless. (If hypoxia were painful, then high-altitude mountaineering would be impossible, rather than just merely hard.) A similar death would occur in a depressurized airline cabin if you don't put your mask on. CO poisoning happens to a 100s of people each year in the U.S. due to faulty heating systems. One reason deaths result is because people aren't aware that it's even happening - they just fall asleep, then die. This is why your home should have at least one CO detector per floor.
Carbon dioxide poisoning, on the other hand, is definitely a rough way to go. Hold your breath for a while and you'll see what I mean. That panic you're feeling, the tightening of the chest, the burning, that's caused by your brainstem realizing your blood has built up too much CO2. At low levels, high CO2 concentration in the air will make your irritable, give you a headache, and generally make it hard to function at your best. (Astronaut Scott Kelly complained about this a lot during his year on the ISS.) Taken higher, and your entire body becomes acidotic, and that feeling of drowning becomes all-encompassing. Eventually, your metabolism will break down at a cellular level as your blood becomes saturated with CO2. You'll have passed out long before that, but your last conscious moments will probably be in agony.
Wait! What's covfefe, precious?"
Yes. That is what you are supposed to do. What is the point of a printed manual for a whiz-bang piece of tech like an Android phone or $2000-$5000 laptop when there is no internet connection? Maybe such tech is still useful without the connection, but that is a tiny minority of use cases. That tiny minority does not justify the expense of preparing, printing, and distributing manuals.
A more common use case would be this: a manufacturer goes through the expense of preparing, printing, and distributing manuals with their product. Then, after all that effort, 75% of end users never even open it. Of those that do open it, most will never reference it later on. A tiny fraction of users will reference several times during the life of the device. Some users will look at the printed manual, puzzle over the table of contents, and wonder where all the hyperlinks are. What, no search tool? Another thing to consider is currency: hardware and software changes often, and probably as soon as the manual was prepared and published, some of the information in it would be dated, misleading, incorrect, or otherwise out-of-sync with reality. Keeping a soft copy up-to-date (like an online support page) is much easier.
Goddammit! I see this conflation of energy in power in the mainstream press all the feakin' time. Kilowatts is not a unit of energy! It's a unit of power (energy consumption over time). If a reporter doesn't know the difference, and doesn't realize that the different is really important, then I can't trust that any of the rest of their reporting is worth my time.
However, since they couldn't be bothered to do even a modicum of technical checking, I will help fill in the blanks. There are two ways to interpret this statement:
In the first case, they would be talking about 70 terawatts of power, and that being 1.8% of the US consumption. This is absurd: the average energy consumption of the U.S. is only a few terawatts.
In the second case, they would be talking about 70 terawatt-hours of energy, implying a total consumption in the U.S.of about 3888 TWh. This is in line with recent statistics for U.S. electricity consumption. However, electricity consumption is not the same as total energy consumption, where one also has to consider energy for heating, transportation, industrial processes, etc.
So, the reporter is talking about energy, not power. He or she doesn't know the correct units, and conflates electrical consumption with total energy consumption. In short, the reporter is sloppy as all get out with their information. No wonder we can't have a proper debate about energy in this country - no one knows what the hell they're talking about.
What got Elon in trouble wasn't trusting the Saudis. His mistake was running his mouth off on twitter, and his overarching desire to stick it to the shorts.
Ah! You must not be living in the United States, then. Around here, even people with medical insurance routinely go into debt and bankruptcy over medical issues.
These kinds of higher-end features have a way of making it down into less expensive models over time. Hell, many of them, like airbags and ABS, have become mandated equipment. So being aware of this as a problem, even a "first world problem" now, and understanding how to mitigate it, will become more important over time.
It is already happening. My in-laws replaced both their cars recently, and specifically looked for these features. They ended up with a Honda Accord and a Rav4, which are most definitely not "higher end cars". (They did have to buy the higher trim levels in order to get these features.) This is becoming mainstream.
I've used all my mod points, otherwise I'd happily mark you "+1 Informative" That is totally rad!
You have to be careful about comparing energy here, though. If you want to compare total energy output (i.e., heat) then, yes, the hydrogen is worse than the natural gas.
But the metric we care about is natural gas input to mechanical work output. In one scenario, you have a natural gas-powered locomotive (do those even exist?), which will be limited to the Carnot efficiency of whatever heat engine you are using to burn the gas and get mechanical work (30%, maybe). Actually, it's probably worse than that, because the locomotive probably can't be directly powered by that heat engine - the range of torque and speed needed at different operating conditions is a terrible match for a gas turbine. Instead, most locomotives (including conventional diesels) burn fuel to run a generator, then have an electric powertrain for the wheels. So there is a further conversion step that will incur an efficiency hit. In all, you might be lucky to get 20% of the natural gas' original potential energy converted into mechanical work.
In the other scenario, you convert the natural gas to H2, then send that through a fuel cell to get electricity, then move the locomotive by an electric motor. The fuel cell is not limited by Carnot efficiency, and the electric --> work conversion in the electric motor has quite high efficiency (85%-95%). I do not have numbers in front of me, but I suspect that you'll find the hydrogen-fueled system gets more mechanical work from the natural gas input than just burning it in an engine.
Your point is valid - most hydrogen is produced by steam reformation of natural gas, which releases CO2. Widescale production of hydrogen without substantial emissions (e.g., electrolysis powered by wind and solar) is still a long ways off
On the other hand, that doesn't mean that it's totally incorrect to refer to hydrogen as "zero emissions." There aren't any emissions from the release of that energy. That is, unlike a diesel locomotive, there are no tailpipe emissions. A pedant would say "well, then, they should clarify and say 'zero tailpipe emissions'", and they would be correct. But emissions from diesel locomotives - and other diesel emissions like trucks and container ships, are sources of substantial air pollution that is a hazard to human health. So switching to hydrogen still has benefits.
And, since you were curious about emissions per kJ output... I suggest having a look at this paper from 2014, comparing the total emissions of a gasoline car to a hydrogen fuel cell equivalent. It's not quite the same comparison as locomotives, but gets the point across. Per distance traveled, the fuel cell vehicle produces 34% fewer CO2 emissions per distance traveled if the hydrogen is sourced from natural gas. As the hydrogen source greens (i.e., electrolysis replaces steam reformation), the emissions drop further.
In this case, there were two reasons: 1) we wanted a 100% sealed case, no ports or anything, and 2) our target audience was the disabled community, who may not have the dexterity (or, in some cases, any hands at all) to make a cabled connection.
I won't be so bold as to crow "Oh, they should have seen this coming." Still, this should not be a surprise, as anyone who has used wireless charging has experienced.
I worked on a product some years ago that was using a competitor to the Qi standard. Our product had a receiver coil that captured the alternating magnetic field, rectified it, and delivered that bulk power to the Li-Ion charge circuit. Worked great, except when you realize that the entire device is immersed in this alternating magnetic field. Every conductor, and in particular every ferromagnetic component (screws, the metal housing of the Li-Ion cell, a metallic portion of the housing, everything) was heating up due to eddy currents. As a stopgap we ended up sticking a ferrite shield over the mat, to isolate only that area where we wanted the charge power to emit. That worked to limit the heating, mostly. But that made it not all that different from most wireless charging cradles before and since, where you have to align the product to the charger. Needing that alignment drastically reduced the utility of the wireless charging, which was one reason why we scrapped it.
Oh, and while we were delivering about 2 W of charge power to the Li-Ion battery, the mat was drawing about 18 W from the wall. Even when the device wasn't present and not charging, the mat drew 10 W. This experience has made me highly skeptical of the prospect of widespread wireless charging anytime soon.
It may also not be about increased precision. It is pretty common in floating-point architectures to allow a 64-bit FPU to perform operations on two 32-bit operands in parallel in the same amount of time. So instead of doing a 64-bit x 64-bit multiplication in some number of clock cycles, it can do two (32-bit x 32-bit) multiplications in the same time. A lot of that can be handled by compiler optimization, too, so that the programmer doesn't even need to plan for it.
It's worse than that - most BECs have a lifetime of fractions of a second. One of the limiting factors on the lifetime of a BEC is, oddly enough, gravity: the clump of particles simply falls out of the trap. A recent delivery to the International Space Station will allow for the creation of BECs with longer lifetimes: 5-10 seconds according to this article. That may still not sound like a lot, but it is an order of magnitude longer, and will allow deeper investigation of these tricky things. The better they are understood, the more likely useful applications may come along.
Greed...is good. Greed is right.
I'm surprised that we've gotten this far into this discussion without someone bringing up this gem from Wall Street
In defense of NASA, this was an idea floated by a political appointee. I highly doubt this is something being pushed by the NASA rank and file. I suspect their reaction is the same as yours and mine.
But in the meantime, NASA is still doing exploration and useful science. They launched the Parker solar probe just a few weeks ago. People are still living on the International Space Station. We have a nuclear-powered rover on Mars that was delivered by a rocket skycrane. On New Years's Day, the New Horizons probe will fly past a Kuiper Belt Object - a spec so tiny they needed teams of telescopes in remote places just to confirm where it's orbit is. And then there's NASA's ongoing development of commercial crew vehicles. SpaceX and Boeing are, naturally, doing the bulk of the work, but NASA has a lot of say in the design and certification. NASA also happens to be the customer. And, oh yeah, when those capsules launch, they'll be crewed by NASA astronauts.