It's pretty tricky, really. You have to simulate at least 4 satellites' signals, compensating for their orbital movement at the position where you want to tell your target it's located.
But its just numbers and time. That's all the GPS receiver knows about. It knows nothing actual orbits or movements. Just precise time and epheremis numbers.The signals would be trivial to generate with a computer.
Let's see your sample code to show it's trivial and your analysis that shows a normal clock can generate 4 or more signals and add them in real time accurately enough to spoof a standard GPS, let alone do what the article talks about and generate a stable enough signal that it can mislead a ship without the crew having a clue that anything is weird.
It seems fairly easy to me. You don't need to "generate 4 or more signals and add them in real time". The "adding them in real time" is trivial, and is handled by the receiver. GPS math is just math. If you were writing it out by hand it would not be fun, but it is trivial for a computer. The equations are solvable with no ambiguity unlike fluid mechanics equations.
What you need to do determine is:
1. "Where do I want the receiver to think it is?" The input. If I wanted the receiver to think it is sitting on the ground, this is just 1 set of coordinates. If I wanted it to think it was following a path, we have a simple equation for that path to generate the proper coordinates. This input equation could be a simple algebraic line, or something more complicated.
2. I invent 4 or more imaginary satellites and place them in orbit at positions of my choosing. The distance from each fake satellite to the intended position in step 1 is calculated. I know both where my imaginary satellites are, and where I want the receiver to think it is. Both locations are known so the distance between them is trivial.
3. I calculate the signals that would be needed from each satellite in order to represent the distance calculated in step 2. This actually quite simple- You only have to create a signal which is supposedly X distance from the receiver. Solving this would require solving something similar to a Doppler equation, which is easy.
4. Broadcast the fake signals from step 3.
5. The receiver does all the other math. That is its job!
Making a GPS antenna that was only good for a half-hemisphere would be the cheaper option. Is there really a great need to obtain GPS signals from the ground? I don't see WAAS being at all critical for drones or regular airplanes. Flying inverted could be a problem, but when you are flying inverted, your location is generally of little concern.
I've had a project canceled because they found out we were using best-of-breed RADIUS. Funk Software's Steel-Belted-RADIUS. We weren't allowed to have any funky servers. Used Windows free RADIUS instead. Lots of headaches.
You need to control problem names from the get-go. Politicians do it all the time when they name bills (Safety Measures YYY for the Children, etc). Good businessmen never ask their boss to travel to Las Vegas, they go to Clark County, NV instead. It is your responsibility to handle this kind of thing.
Why would anyone ever voluntarily suffer on behalf of another?
That is a question that hundreds of very smart people have studied for at least a 150 years. In fact, Charles Darwin struggled with it because it was a big hole in his theories. And it is not limited to humans or even mammals.
The simple answer is that it always seems to benefit the individual, somehow.
We melt for about a week a year, so we just endure - the awkwardness is over too soon to justify building houses that stay cool (And thus cost a lot more to heat in winter).....
Buildings that stay cool in summer and are warm in winter are not mutually exclusive. Presenting them as conflicting design goals is silly considering that these design goals are often complementary.
Looking at the 7" tablets, it seems like these devices are all quite similar:
Google Nexus 7
Lenovo IdeaTab A3000
Samsung Galaxy 3 7"
All roughly $200. Front and back cameras, vaguely comparable processors. The Nexus has a higher screen resolution than the other two, but lacks the microSD slot that the other two have. The Samsung uses its own Samsung app store, while the Google and Lenovo use the Google Play store. Anything else different?
Of course they are quite similar. They are all made in China by the same suppliers. The only difference is how locked down the company wants to make them, and how they want to monetize them after-sale.
You can buy a chinese tablet straight from China for about 25%-30% less with the exact same specs. Some of the extra cost in the Google/Samsung models is due to better and more consistent software, but a good portion of it is going right into the pocket of those middlemen.
I have yet to see a Chinese tablet that did not have a micro-SD slot. Even their $40 devices have them. The only reason Apple and Google would do without them is so they can gouge the customer for extra storage and built-in obsolescence.
Storage isn't a problem, it's the cheapest part of the equation. Energy consumption is the biggest technical challenge due to the global domination of mobile devices and the current limitations in energy storage.
But there are bandwidth limitations on many devices. Limitations which are generally fine now for 1080p, but could be a problem with "something better", or with multiple streams of "something better".
Plus, this article deals with the compression part of the video encoding. Most media is decompressed many many times, but only compressed once. It is reasonable to assume that decompression will be more taxing with x265 compared to x264, but that isn't a part of this article. How much more CPU is required for decompressing x265 compared to x264? That isn't so clear at the moment, and since the code isn't finalized, results today may have no bearing on tomorrow anyhow.
The biggest problem nowadays is that a movie must have a simple enough story to be marketable in the international market, and specifically the Chinese market. 2/3s of all of Hollywood's revenue now comes from international distribution.
Why does a story have to be "simple" in order to be well understood in an international market? As long as country-specific scenarios or themes are avoided, and the translating team is decent, I don't see the problem with a complicated storyline.
All of the UK's current nuclear reactors use seawater for cooling. Many coal-fired power stations (but not all of them) are also on the coast or estuaries and similarly use seawater for their cooling loops.
Corrosion is not a problem, just use marine-rated stainless steel pumps and piping for the loops and carry out preventative maintenance every now and then. Odd problems with seawater cooling do occur, such as a plague of jellyfish which threatened to block the seawater intakes at a Scottish reactor site and they were shut down for a time as a precaution.
I have noticed that direct cooling (seawater/riverwater/lakewater) is popular in Europe. It fell out of favor in the US a while ago because the permitting was too troublesome. I haven't heard of a direct cooling water plant in the US built in the last 20 years. The US uses mostly air cooling or cooling towers. Air cooling is ideal environmentally, but is not nearly as efficient- thermodynamially it is worse and dozens of fans cost more to operate compared to pumps. Cooling towers are nearly as good as direct cooling and can be made to be relatively water-efficient.
It is a complete mystery to me why direct cooling is still used in environmentally-liberal Europe but is practically outlawed in the global-warming-denying USA.
Really. All this work for a lousy student government election which in the real world means absolutely nothing!?!
He should have remembered that episode of the Simpsons where Bart runs for class president and loses.
Homer: Bart, does the class president get paid?
Bart: No.
This position had a large stipend attached. $8000 is a lot for a student. I don't know why the summaries never mention this. I guess it makes for more controversy when it is fraud for something rather meaningless rather than plain old fraud for cash.
The "paperwork" has never been lost—every shred of documentation is intact and on file. In fact, engineers at Marshall Space Flight Center have been spending the past year busily disassembling and working with components from several stored F-1 engines. They've constructed highly detailed CAD models of the engines, and even done hot firing on one of the gas generator segments.
I penned a very detailed piece on this over at Ars Technica earlier this year, including photos and video of one of the gas generator hot-fires. The piece includes multiple interviews with senior propulsion scientists at MSFC, and thoroughly debunks the "but the blueprints are lost!" urban myth.
The first stage rocket engine is not a complete rocket. Aruably the engine is very important, but many other things are important too. The underlying point is we can't built a Saturn 5 again. We would need to basically redesign the whole rocket to get there.
Which manufacturers? Toyota offers stick on pretty much every modem afaik. Trucks for sure, though you can buy one off the lot the dealer should be able to find one for you and you just have to wait a few weeks for delivery. I have to admit though I haven't seen a stick Toyota sedan built recently but I haven't really looked either.
Mainstream car makers treat people who want a manual transmission and people who want something other than the barest trim option as mutually exclusive. Want a Camry with a stick? Its possible, but no leather for you. How about a Subaru Outback with a 5-speed? No problem, just forget about the navigation and the sunroof because you can't have them. Minivan with a stick- no problem. Minivan with a stick and rear entertainment system? Not possible.
The only exceptions are in the luxury car makers like BMW, Acura, etc. Sometimes.
And I'm not arguing "if you can afford it", but the majority of people cannot, and when they look at their "needed $500/mo car expense" and then wonder why they are having trouble making ends meet, it's ridiculous.
I have heated seats in my car too. Cloth. GP says that heated leather seats are nice in the winter, but you know what is nicer? Heated cloth. I won't completely freeze your ass before the heating comes up to temperature. Cloth is better on a hot day too- just try sitting on a hot cloth seat with shorts and compare to a hot leather seat. I love the feeling of leather but it is only really best on medium-temperature days.
Sidenote- You can buy aftermarket seat heaters for $65/seat and put them in yourself. Or have a stereo guy put them in for maybe $300. Either way it is a better deal than the "cold weather package" which is usually $2-3000.
Completely unrelated- it is a bit frustrating that if you want a 5/6 speed on a non-luxury vehicle, you have to settle for the base model. The higher trim models of most non-luxury cars have no manual transmission option.
Supervising the little green army men riding around on mice twirling lasso's made of fishing line. Electrified fences tens of millimeters high. Dangerous stampetes potentially costing small insects their lives. Ah, the life of a guinea pig rancher.
Yes coal is a major source of electricity, about 40%, and it is going to get harder with new regulation. But again, like nuclear, the reason we building more coal plants it dogma. People believe it is the best solution. It is certainly a profitable solution. There are tens of thousands of people who are willing to dig coal for a middle class income in working conditions that keep the overall costs low.
Natural gas is actually giving coal a serious run for the money right now. Part is efficiency and part is fuel cost. About the best we can achieve with a coal plant is around 40% efficiency, which is not that bad considering the thermodynamics and represents over 100 years of improvements in the process. Gas-powered combined cycle plants play with the thermodynamics in ways that the coal plant fundamentally can not reach, so they can get 60% efficiency.
Add to that the fact that natural gas, especially in the US, is at a historical all-time low, and you arrive at the fact that nobody has ordered a coal plant in the last 4-5 years. Some came online fairly recently, but they were all ordered back in the early-mid 2000's when gas was expensive. Gas is cheap around the world right now, but in the US, it is roughly 1/4 the price compared to Europe and 1/3 the price compared to Russia.
So, in fact, we are not building new coal plants, and the reason is mostly economical (with many permitting considerations also). According to the accountants, it is not "the best" or the most profitable solution. This is all great in the short term, natural gas is 99% methane and burns clean, the US can become very slightly less reliant on foreign sources of energy*, etc. But I have to ask, what happens when gas is not cheap? Sooner or later the price of gas in the US is going to be closer to the price in the rest of the world, and that day is going to bring down a lot of pain on the US.
*oil-fired power plants make up only a tiny percentage of the US power mix. It is simply too expensive to burn for electricity, and has been for a long time. Since the number of natural gas cars in the US is really tiny, cheap natural gas doesn't really decrease our oil usage in any meaningful way. This doesn't stop politicians from trumpeting this misconception however.
An article that decries all the valuable, important stuff that could have been brought up, but then doesn't bother to bring them up and/or discuss them in any detail?
This article was a waste of my time. I wish Slashdot had a thumbs up/down on articles.
Well I can't speak for the nuclear side of it, but the steam turbines had problems too. One was that they were getting buildup in the generator stator core cooling tubes.
See, a large steam turbine like this has a really massive electric generator. In most motors that people think of, the windings are made of copper wire. However, in large generators, these wires are replaced with copper strands roughly 2mm by 5mm or so, which are then bundled into groups of 100 or more in a rectangular shape. Usually, the resistance losses are such that air or hydrogen cooling is enough. However, when you start pushing around thousands of amps, even very small resistance losses turn into a lot of heat. At a certain point when you are making a generator larger and larger, all that copper becomes prohibitively expensive.
The first thing to do is replace the air with hydrogen. Hydrogen has less cooling capacity, but it is far less dense than air so the air friction of the rotor is much less, resulting in less heat. In truly large machines, however, that isn't enough. Above around 350MW, you make a portion of these copper strands hollow and pump water through them.
The combination of water, thousands of amps, and hydrogen sounds pretty dangerous, and you would be right in thinking that a lot of machines went BOOM before they nailed all the potential problems. One problem though remains the chemistry of the water in the copper strands. Demineralized, oxygen-free water is generally used, along with oxygen-free 99.999% pure copper. If a large amount of oxygen is in the water, there start to be buildups of gunk in the tiny strands, which can not be cleaned mechanically. You can search "oxygen in stator cooling water" on google and get a few articles. The only way to clean it is with an acid wash, and engineers get nervous about this because if you clean out all the gunk, invariably you have also caused material loss of your copper.
Which brings me in a very roundabout way back to San Onofre. They did everything right, but kept getting gunk in their copper strands. No oxygen in their water, and the water conductivity was more than high enough (sufficiently pure). And yes, they did check to make sure that water measurements were correct. Nevertheless, they were needing to acid-clean their generator stator copper strands every 2-4 years, which is alarming considering that the average machine only requires such acid cleaning between 0 and 2 times in a 40 year lifespan. Nobody has ever required this much acid cleaning, so the point at which the copper strands become too eroded by the acid is not clear. I'm sure some regulator was watching this very closely because of the huge disaster a water leak can have.
The only way out of this mess would have been be a new stator, or a rewind. A stator of that size weighs more than can not be transported in once piece, since it weighs at least 2 million pounds (no exaggeration). Building it or rebuilding it on site costs tens of millions of dollars just in labor and windings, not to mention all the lost generation.
This electrical generator problem certainly didn't sink San Onofre by itself, but it didn't help things either. I suspect there were a few other issues which would require a huge investment of money at a time when California is broke, the utility has a hard time getting a rate increase, and natural gas is cheaper than it has ever been in the US (there are basically 0 operating coal plants in California, although there are some just across state lines which sell exclusively to California). It probably would be cheaper in the long run to repair and refit San Onofre, but when money is tight, short term solutions take priority.
The containers don't magically appear next to the crane for loading onto the ship. They have to be lifted off of trains or trucks which bring them to the docks. Then they sit and wait for the ship to arrive and be unloaded. Then they're loaded onto the ship. It'd be trivial to weigh them when they're first taken off the train or truck.
A more prone failure point is corruption among the dockyard workers - they get bribed to ignore that a container is overweight.
My point, which I should have explained better, is that the loading plan is ship-specific, and the computer program running the calculations is either on the ship, or in the ship management office (at the shipping company), or both. There are many different software packages for ship loading, and they all get customized for each ship. It isn't practical for the port to keep all the different software packages and all the variations for each ship on file. And anyway, it is not the port's responsibility to make sure the ship is safely loaded. It is the captain's (and his support team back at HQ).
The weights need to be given in advance because the fees and tarriffs have to be charged, or at least quoted, to the person sending the container before they decide to use X shipping company. Any discrepancy is unlikely to be large, so it is possible that the shipping company just uses the weights given in advance.
Do you have any examples that bribing dock workers to ignore overweight containers happens? Because to me, it seems completely impossible to believe that Joe's Export company would bother to send a person to the port, find a specific container among tens or hundreds of thousands of containers, and give a specific dock worker(s) cash to ignore a problem with that container. It would be cheaper to just pay the extra tarriff! It would also open Joe's Export company up to a bribery scandal, which is a stupid thing to do over a couple hundred dollars in extra tarriff per container.
The only logistically practical way would be for a broker company to give contributions to the longshoremen union. I don't think that would give results.
One would think they'd weigh the container themselves and charge accordingly. But then I'm not in the shipping business so I dunno...
The Maersk EEE class ships can hold roughly 18,000 20-foot containers. Do you think it is practical to weigh all of them?
It is relatively easy to put a load cell on a crane and weigh a container there. One could envision a system where the crane weighed the container and then decided where it should go. However, this is tricky because these ships are usually loaded by many cranes at once and you can't decide that the container is too heavy and should be put in place by a different crane.
That is because you don't understand what is being called an "internet café". There are places here that call themselves "internet cafés" who offer "games" which are actually nothing more than slot machine parlors using virtual slot machines running on PCs.
Ah, so they run World of Warcraft and Diablo III then.
I call nonsense on you. Perfect example: Waterproofing. It would be trivial to make a waterproof (or at least water resistant) phone. Yet there are none. In fact, just having your phone in a overly humid environment will likely ruin it. This is clearly by design.
There are plenty. Casio has a complete line of phones under the Gzone line (Warning- possibly the worst website I have ever seen). Catarpillar makes (or at least specs out and has someone make) one or two also.
The magic google words are "810g phone" (referring to the mil-spec) or "IP67 phone"
I've heard time and time again, that Canadian (and American) men are highly desired by women in Japan. I've also heard time and time again, that the reason is because too many Japanese men are downright useless and misogynistic assholes.
Are you a genuinely nice North American dude with a real job? If so, it really is remarkably easy to meet wonderful women in Japan.
You've heard. The reality is quite different however. There are about 50,000 Americans living in Japan. There are about 40,000 US military personnel in Japan at any given time. Being a military wife might be attractive to some, but for most families in Japan it would be an embarrassment. Because of the high number of US military compared to general Americans living in Japan, if you see a white guy wandering around who isn't wearing a suit, it isn't a bad guess to think he is in the military, and therefore undesirable. The stereotype bleeds over a bit into any american, even if they have nothing to do with the military.
American men are different than Japanese men, but it would be a huge mistake to think or imply that one is more desirable in Japan than the other. And reporting that American men can find a lady in Japan with little or no effort is completely wrong.
More bandwidth to suck my pc dry of all information!
What they are forgetting is that they ISP must have 100Tbps links then... 100G is already out there. But it is used to aggregate lots of 20Mbps links. If you have 1000000 subscribers on 100G links, you will need at least 1000000G to provide them with access, assuming 1:10 overbooking.
Until something faster than SATA3.0 gets a marketshare, I think it is safe to assume that only a very very tiny percentage of customers will even break 6Gbit for any length of time. 1Gbit is probably more than plenty for a household for the next 10 years.
In 2003, 512mb of ram was common and the PATA133 spec could do 133MB/s (or about 1Gbit/s) in the ideal case. Now we have 8gb or 16gb of RAM being common and a 6Gbit/s disk interface. At 100Gbit, 1TB of data is transferred in about 90 seconds. In 2023, we might have computers with 256GB of ram and a disk interface that can do 36Gbit. 4k uncompressed video is only about 3.7Gbit. I have a hard time believing that even in 2027 (15 years), 100Gbit will be all that useful for the home user.
I have used radio controlled, WWVB clocks for many years and one thing they are NOT is "reliable", at least not where I live.
It occurs to me that if the signals have almost no chance of reaching China according to the coverage maps, the factory making these things is probably just guessing if it works or not.
Even if they have some sort of signal generator mockup, it would seem to be difficult to replicate exact local conditions in the USA.
Slashdot Mirror
It's pretty tricky, really. You have to simulate at least 4 satellites' signals, compensating for their orbital movement at the position where you want to tell your target it's located.
But its just numbers and time. That's all the GPS receiver knows about. It knows nothing actual orbits or movements. Just precise time and epheremis numbers. The signals would be trivial to generate with a computer.
Let's see your sample code to show it's trivial and your analysis that shows a normal clock can generate 4 or more signals and add them in real time accurately enough to spoof a standard GPS, let alone do what the article talks about and generate a stable enough signal that it can mislead a ship without the crew having a clue that anything is weird.
It seems fairly easy to me. You don't need to "generate 4 or more signals and add them in real time". The "adding them in real time" is trivial, and is handled by the receiver. GPS math is just math. If you were writing it out by hand it would not be fun, but it is trivial for a computer. The equations are solvable with no ambiguity unlike fluid mechanics equations.
What you need to do determine is:
1. "Where do I want the receiver to think it is?" The input. If I wanted the receiver to think it is sitting on the ground, this is just 1 set of coordinates. If I wanted it to think it was following a path, we have a simple equation for that path to generate the proper coordinates. This input equation could be a simple algebraic line, or something more complicated.
2. I invent 4 or more imaginary satellites and place them in orbit at positions of my choosing. The distance from each fake satellite to the intended position in step 1 is calculated. I know both where my imaginary satellites are, and where I want the receiver to think it is. Both locations are known so the distance between them is trivial.
3. I calculate the signals that would be needed from each satellite in order to represent the distance calculated in step 2. This actually quite simple- You only have to create a signal which is supposedly X distance from the receiver. Solving this would require solving something similar to a Doppler equation, which is easy.
4. Broadcast the fake signals from step 3.
5. The receiver does all the other math. That is its job!
Making a GPS antenna that was only good for a half-hemisphere would be the cheaper option. Is there really a great need to obtain GPS signals from the ground? I don't see WAAS being at all critical for drones or regular airplanes. Flying inverted could be a problem, but when you are flying inverted, your location is generally of little concern.
I've had a project canceled because they found out we were using best-of-breed RADIUS. Funk Software's Steel-Belted-RADIUS. We weren't allowed to have any funky servers. Used Windows free RADIUS instead. Lots of headaches.
You need to control problem names from the get-go. Politicians do it all the time when they name bills (Safety Measures YYY for the Children, etc). Good businessmen never ask their boss to travel to Las Vegas, they go to Clark County, NV instead. It is your responsibility to handle this kind of thing.
Why would anyone ever voluntarily suffer on behalf of another?
That is a question that hundreds of very smart people have studied for at least a 150 years. In fact, Charles Darwin struggled with it because it was a big hole in his theories. And it is not limited to humans or even mammals.
The simple answer is that it always seems to benefit the individual, somehow.
We melt for about a week a year, so we just endure - the awkwardness is over too soon to justify building houses that stay cool (And thus cost a lot more to heat in winter) .....
Buildings that stay cool in summer and are warm in winter are not mutually exclusive. Presenting them as conflicting design goals is silly considering that these design goals are often complementary.
Looking at the 7" tablets, it seems like these devices are all quite similar:
All roughly $200. Front and back cameras, vaguely comparable processors. The Nexus has a higher screen resolution than the other two, but lacks the microSD slot that the other two have. The Samsung uses its own Samsung app store, while the Google and Lenovo use the Google Play store. Anything else different?
Of course they are quite similar. They are all made in China by the same suppliers. The only difference is how locked down the company wants to make them, and how they want to monetize them after-sale.
You can buy a chinese tablet straight from China for about 25%-30% less with the exact same specs. Some of the extra cost in the Google/Samsung models is due to better and more consistent software, but a good portion of it is going right into the pocket of those middlemen.
I have yet to see a Chinese tablet that did not have a micro-SD slot. Even their $40 devices have them. The only reason Apple and Google would do without them is so they can gouge the customer for extra storage and built-in obsolescence.
Storage isn't a problem, it's the cheapest part of the equation. Energy consumption is the biggest technical challenge due to the global domination of mobile devices and the current limitations in energy storage.
But there are bandwidth limitations on many devices. Limitations which are generally fine now for 1080p, but could be a problem with "something better", or with multiple streams of "something better".
Plus, this article deals with the compression part of the video encoding. Most media is decompressed many many times, but only compressed once. It is reasonable to assume that decompression will be more taxing with x265 compared to x264, but that isn't a part of this article. How much more CPU is required for decompressing x265 compared to x264? That isn't so clear at the moment, and since the code isn't finalized, results today may have no bearing on tomorrow anyhow.
The biggest problem nowadays is that a movie must have a simple enough story to be marketable in the international market, and specifically the Chinese market. 2/3s of all of Hollywood's revenue now comes from international distribution.
Why does a story have to be "simple" in order to be well understood in an international market? As long as country-specific scenarios or themes are avoided, and the translating team is decent, I don't see the problem with a complicated storyline.
All of the UK's current nuclear reactors use seawater for cooling. Many coal-fired power stations (but not all of them) are also on the coast or estuaries and similarly use seawater for their cooling loops.
Corrosion is not a problem, just use marine-rated stainless steel pumps and piping for the loops and carry out preventative maintenance every now and then. Odd problems with seawater cooling do occur, such as a plague of jellyfish which threatened to block the seawater intakes at a Scottish reactor site and they were shut down for a time as a precaution.
I have noticed that direct cooling (seawater/riverwater/lakewater) is popular in Europe. It fell out of favor in the US a while ago because the permitting was too troublesome. I haven't heard of a direct cooling water plant in the US built in the last 20 years. The US uses mostly air cooling or cooling towers. Air cooling is ideal environmentally, but is not nearly as efficient- thermodynamially it is worse and dozens of fans cost more to operate compared to pumps. Cooling towers are nearly as good as direct cooling and can be made to be relatively water-efficient.
It is a complete mystery to me why direct cooling is still used in environmentally-liberal Europe but is practically outlawed in the global-warming-denying USA.
Really. All this work for a lousy student government election which in the real world means absolutely nothing!?!
He should have remembered that episode of the Simpsons where Bart runs for class president and loses.
Homer: Bart, does the class president get paid? Bart: No.
This position had a large stipend attached. $8000 is a lot for a student. I don't know why the summaries never mention this. I guess it makes for more controversy when it is fraud for something rather meaningless rather than plain old fraud for cash.
The "paperwork" has never been lost—every shred of documentation is intact and on file. In fact, engineers at Marshall Space Flight Center have been spending the past year busily disassembling and working with components from several stored F-1 engines. They've constructed highly detailed CAD models of the engines, and even done hot firing on one of the gas generator segments.
I penned a very detailed piece on this over at Ars Technica earlier this year, including photos and video of one of the gas generator hot-fires. The piece includes multiple interviews with senior propulsion scientists at MSFC, and thoroughly debunks the "but the blueprints are lost!" urban myth.
The first stage rocket engine is not a complete rocket. Aruably the engine is very important, but many other things are important too. The underlying point is we can't built a Saturn 5 again. We would need to basically redesign the whole rocket to get there.
Which manufacturers? Toyota offers stick on pretty much every modem afaik. Trucks for sure, though you can buy one off the lot the dealer should be able to find one for you and you just have to wait a few weeks for delivery. I have to admit though I haven't seen a stick Toyota sedan built recently but I haven't really looked either.
Mainstream car makers treat people who want a manual transmission and people who want something other than the barest trim option as mutually exclusive. Want a Camry with a stick? Its possible, but no leather for you. How about a Subaru Outback with a 5-speed? No problem, just forget about the navigation and the sunroof because you can't have them. Minivan with a stick- no problem. Minivan with a stick and rear entertainment system? Not possible.
The only exceptions are in the luxury car makers like BMW, Acura, etc. Sometimes.
if we don't trust Microsoft and Google, who is left?
Don't even think about trusting yourself. I made that mistake once, and I slipped myself some roofies and date-raped myself.
The $16k car I bought included heated seats..
And I'm not arguing "if you can afford it", but the majority of people cannot, and when they look at their "needed $500/mo car expense" and then wonder why they are having trouble making ends meet, it's ridiculous.
I have heated seats in my car too. Cloth. GP says that heated leather seats are nice in the winter, but you know what is nicer? Heated cloth. I won't completely freeze your ass before the heating comes up to temperature. Cloth is better on a hot day too- just try sitting on a hot cloth seat with shorts and compare to a hot leather seat. I love the feeling of leather but it is only really best on medium-temperature days.
Sidenote- You can buy aftermarket seat heaters for $65/seat and put them in yourself. Or have a stereo guy put them in for maybe $300. Either way it is a better deal than the "cold weather package" which is usually $2-3000.
Completely unrelated- it is a bit frustrating that if you want a 5/6 speed on a non-luxury vehicle, you have to settle for the base model. The higher trim models of most non-luxury cars have no manual transmission option.
...Marco, who has a guinea pig ranch...
Supervising the little green army men riding around on mice twirling lasso's made of fishing line. Electrified fences tens of millimeters high. Dangerous stampetes potentially costing small insects their lives. Ah, the life of a guinea pig rancher.
Yes coal is a major source of electricity, about 40%, and it is going to get harder with new regulation. But again, like nuclear, the reason we building more coal plants it dogma. People believe it is the best solution. It is certainly a profitable solution. There are tens of thousands of people who are willing to dig coal for a middle class income in working conditions that keep the overall costs low.
Natural gas is actually giving coal a serious run for the money right now. Part is efficiency and part is fuel cost. About the best we can achieve with a coal plant is around 40% efficiency, which is not that bad considering the thermodynamics and represents over 100 years of improvements in the process. Gas-powered combined cycle plants play with the thermodynamics in ways that the coal plant fundamentally can not reach, so they can get 60% efficiency.
Add to that the fact that natural gas, especially in the US, is at a historical all-time low, and you arrive at the fact that nobody has ordered a coal plant in the last 4-5 years. Some came online fairly recently, but they were all ordered back in the early-mid 2000's when gas was expensive. Gas is cheap around the world right now, but in the US, it is roughly 1/4 the price compared to Europe and 1/3 the price compared to Russia.
So, in fact, we are not building new coal plants, and the reason is mostly economical (with many permitting considerations also). According to the accountants, it is not "the best" or the most profitable solution. This is all great in the short term, natural gas is 99% methane and burns clean, the US can become very slightly less reliant on foreign sources of energy*, etc. But I have to ask, what happens when gas is not cheap? Sooner or later the price of gas in the US is going to be closer to the price in the rest of the world, and that day is going to bring down a lot of pain on the US.
*oil-fired power plants make up only a tiny percentage of the US power mix. It is simply too expensive to burn for electricity, and has been for a long time. Since the number of natural gas cars in the US is really tiny, cheap natural gas doesn't really decrease our oil usage in any meaningful way. This doesn't stop politicians from trumpeting this misconception however.
An article that decries all the valuable, important stuff that could have been brought up, but then doesn't bother to bring them up and/or discuss them in any detail?
This article was a waste of my time. I wish Slashdot had a thumbs up/down on articles.
Well I can't speak for the nuclear side of it, but the steam turbines had problems too. One was that they were getting buildup in the generator stator core cooling tubes.
See, a large steam turbine like this has a really massive electric generator. In most motors that people think of, the windings are made of copper wire. However, in large generators, these wires are replaced with copper strands roughly 2mm by 5mm or so, which are then bundled into groups of 100 or more in a rectangular shape. Usually, the resistance losses are such that air or hydrogen cooling is enough. However, when you start pushing around thousands of amps, even very small resistance losses turn into a lot of heat. At a certain point when you are making a generator larger and larger, all that copper becomes prohibitively expensive.
The first thing to do is replace the air with hydrogen. Hydrogen has less cooling capacity, but it is far less dense than air so the air friction of the rotor is much less, resulting in less heat. In truly large machines, however, that isn't enough. Above around 350MW, you make a portion of these copper strands hollow and pump water through them.
The combination of water, thousands of amps, and hydrogen sounds pretty dangerous, and you would be right in thinking that a lot of machines went BOOM before they nailed all the potential problems. One problem though remains the chemistry of the water in the copper strands. Demineralized, oxygen-free water is generally used, along with oxygen-free 99.999% pure copper. If a large amount of oxygen is in the water, there start to be buildups of gunk in the tiny strands, which can not be cleaned mechanically. You can search "oxygen in stator cooling water" on google and get a few articles. The only way to clean it is with an acid wash, and engineers get nervous about this because if you clean out all the gunk, invariably you have also caused material loss of your copper.
Which brings me in a very roundabout way back to San Onofre. They did everything right, but kept getting gunk in their copper strands. No oxygen in their water, and the water conductivity was more than high enough (sufficiently pure). And yes, they did check to make sure that water measurements were correct. Nevertheless, they were needing to acid-clean their generator stator copper strands every 2-4 years, which is alarming considering that the average machine only requires such acid cleaning between 0 and 2 times in a 40 year lifespan. Nobody has ever required this much acid cleaning, so the point at which the copper strands become too eroded by the acid is not clear. I'm sure some regulator was watching this very closely because of the huge disaster a water leak can have.
The only way out of this mess would have been be a new stator, or a rewind. A stator of that size weighs more than can not be transported in once piece, since it weighs at least 2 million pounds (no exaggeration). Building it or rebuilding it on site costs tens of millions of dollars just in labor and windings, not to mention all the lost generation.
This electrical generator problem certainly didn't sink San Onofre by itself, but it didn't help things either. I suspect there were a few other issues which would require a huge investment of money at a time when California is broke, the utility has a hard time getting a rate increase, and natural gas is cheaper than it has ever been in the US (there are basically 0 operating coal plants in California, although there are some just across state lines which sell exclusively to California). It probably would be cheaper in the long run to repair and refit San Onofre, but when money is tight, short term solutions take priority.
The containers don't magically appear next to the crane for loading onto the ship. They have to be lifted off of trains or trucks which bring them to the docks. Then they sit and wait for the ship to arrive and be unloaded. Then they're loaded onto the ship. It'd be trivial to weigh them when they're first taken off the train or truck. A more prone failure point is corruption among the dockyard workers - they get bribed to ignore that a container is overweight.
My point, which I should have explained better, is that the loading plan is ship-specific, and the computer program running the calculations is either on the ship, or in the ship management office (at the shipping company), or both. There are many different software packages for ship loading, and they all get customized for each ship. It isn't practical for the port to keep all the different software packages and all the variations for each ship on file. And anyway, it is not the port's responsibility to make sure the ship is safely loaded. It is the captain's (and his support team back at HQ).
The weights need to be given in advance because the fees and tarriffs have to be charged, or at least quoted, to the person sending the container before they decide to use X shipping company. Any discrepancy is unlikely to be large, so it is possible that the shipping company just uses the weights given in advance.
Do you have any examples that bribing dock workers to ignore overweight containers happens? Because to me, it seems completely impossible to believe that Joe's Export company would bother to send a person to the port, find a specific container among tens or hundreds of thousands of containers, and give a specific dock worker(s) cash to ignore a problem with that container. It would be cheaper to just pay the extra tarriff! It would also open Joe's Export company up to a bribery scandal, which is a stupid thing to do over a couple hundred dollars in extra tarriff per container.
The only logistically practical way would be for a broker company to give contributions to the longshoremen union. I don't think that would give results.
so they operate on an honor system?
One would think they'd weigh the container themselves and charge accordingly. But then I'm not in the shipping business so I dunno...
The Maersk EEE class ships can hold roughly 18,000 20-foot containers. Do you think it is practical to weigh all of them?
It is relatively easy to put a load cell on a crane and weigh a container there. One could envision a system where the crane weighed the container and then decided where it should go. However, this is tricky because these ships are usually loaded by many cranes at once and you can't decide that the container is too heavy and should be put in place by a different crane.
I encourage everyone to click on the first link, there are bunch of great photos, all on one page (no slideshow).
That is because you don't understand what is being called an "internet café". There are places here that call themselves "internet cafés" who offer "games" which are actually nothing more than slot machine parlors using virtual slot machines running on PCs.
Ah, so they run World of Warcraft and Diablo III then.
I call nonsense on you. Perfect example: Waterproofing. It would be trivial to make a waterproof (or at least water resistant) phone. Yet there are none. In fact, just having your phone in a overly humid environment will likely ruin it. This is clearly by design.
There are plenty. Casio has a complete line of phones under the Gzone line (Warning- possibly the worst website I have ever seen). Catarpillar makes (or at least specs out and has someone make) one or two also.
The magic google words are "810g phone" (referring to the mil-spec) or "IP67 phone"
I've heard time and time again, that Canadian (and American) men are highly desired by women in Japan. I've also heard time and time again, that the reason is because too many Japanese men are downright useless and misogynistic assholes. Are you a genuinely nice North American dude with a real job? If so, it really is remarkably easy to meet wonderful women in Japan.
You've heard. The reality is quite different however. There are about 50,000 Americans living in Japan. There are about 40,000 US military personnel in Japan at any given time. Being a military wife might be attractive to some, but for most families in Japan it would be an embarrassment. Because of the high number of US military compared to general Americans living in Japan, if you see a white guy wandering around who isn't wearing a suit, it isn't a bad guess to think he is in the military, and therefore undesirable. The stereotype bleeds over a bit into any american, even if they have nothing to do with the military.
American men are different than Japanese men, but it would be a huge mistake to think or imply that one is more desirable in Japan than the other. And reporting that American men can find a lady in Japan with little or no effort is completely wrong.
More bandwidth to suck my pc dry of all information!
What they are forgetting is that they ISP must have 100Tbps links then... 100G is already out there. But it is used to aggregate lots of 20Mbps links. If you have 1000000 subscribers on 100G links, you will need at least 1000000G to provide them with access, assuming 1:10 overbooking.
Until something faster than SATA3.0 gets a marketshare, I think it is safe to assume that only a very very tiny percentage of customers will even break 6Gbit for any length of time. 1Gbit is probably more than plenty for a household for the next 10 years.
In 2003, 512mb of ram was common and the PATA133 spec could do 133MB/s (or about 1Gbit/s) in the ideal case. Now we have 8gb or 16gb of RAM being common and a 6Gbit/s disk interface. At 100Gbit, 1TB of data is transferred in about 90 seconds. In 2023, we might have computers with 256GB of ram and a disk interface that can do 36Gbit. 4k uncompressed video is only about 3.7Gbit. I have a hard time believing that even in 2027 (15 years), 100Gbit will be all that useful for the home user.
I have used radio controlled, WWVB clocks for many years and one thing they are NOT is "reliable", at least not where I live.
It occurs to me that if the signals have almost no chance of reaching China according to the coverage maps, the factory making these things is probably just guessing if it works or not.
Even if they have some sort of signal generator mockup, it would seem to be difficult to replicate exact local conditions in the USA.