Why on earth would you think that it is a universal that pubic transport "takes significantly longer to get [where you want to go]"?
My experiance (I live in a major conurbation in the north of the UK and don't drive) is that there are a handful of cases where public transport is faster. Some cities are so congested you don't want to drive into the city center and some of the flagship long distance rail lines run faster than the legal speed limit for cars. If you carefully plan where you live compared to where you work you can get the commute down to a manageable length by making it a single leg journey.
However unless at least one of your origin/destination is in the center of a big city or the two places happen to be on the same public transport route then driving is most likely significantly faster.
During the 2008 crash, SpaceX nearly went under, but was saved by a fixed cost contract to NASA to carry cargo to the International Space Station.
That wasn't the first time NASA had awarded them a contract though, they were also awarded the COTS contract in 2006 to demonstrate commercial orbital transport services.
Since then, most of their launches are for satellites for companies outside the US.
Out of the 23 falcon 9 launches I count 12 where the primary payload was partially or wholly for the US government
2 NASA COTS 8 NASA CRS 1 USAF/NASA/NOAA collaboration 1 NASA/NOAA/CNES
The remaining 11 break down as
1 spacex demo flight 1 payload where the immediate customer was a private canadian company but the final user of the payload was the canadian government. 1 payload for the Turkmenistan National Space Agency 8 flights where the primary payload was communication or broadcast sattelites (sometimes with more than one sattelite per flight)
I agree that spacex is closer to what one would consider a normal private company than ULA but it's also pretty clear that a lot of spacex's revenue comes from the US government and that NASA took a punt on them. When the CRS contract was awarded Falcon 9 had not flown at all and Falcon 1 had only flown test flights.
At least in the US and the UK it's possible to legally fly without a license. To do so your craft has to be very light, in the case of the UK it has to be foot launched and you have to avoid certain airspace. If you want to fly something bigger you need successively tougher licenses. Not much different from the roads really.
I'm mostly thinking of the situation where due to under-investment and the unpredictability of renewables demand sometimes outstrips supply and this is a reasonablly predictable/routine thing.
Without smart meters there is little* incentive for customers to move their electricity consumption to low-demand times and if the supplier does have to resort to cutting customers off they can only include/exclude customers in large blocks. That means the only way they can forciblly reduce consumption is rolling blackouts and they have to be really stingy with who they give out exemptions to since exempting one customer will likely also exempt a bunch arround them.
Having near-realtime metering and a power switch at every customer connection gives them far more options. It may be that variable pricing schemes are enough of a carrot on their own to make people move their consumption to quieter times but if they prove insufficient then rationing schemes would also be possible.
* Some areas have multi-rate conventional meters, but these are a fairly blunt instrument and can only work on long term trends (e.g. day/night), they can't help much with sudden peaks or troughs.
Afaict they have attempted landings* on 6 flights of those two were successful.
Flight 14, failure due to grid fins ran out of hydralic fluid. Flight 17, failure due to stuck valve Flight 20, successful landing at the cape Flight 21, failure due to landing leg issue Flight 22, failure (and was expected to fail) due to coming in too fast due to a large payload. Flight 23, successful landing on
So basically the devil is in the details. Each time a failure happens i'm sure they put a lot of effort into working out the details of what went wrong but what is not clear is how many iterations of failure they will have to go through before they get a reliable result.
One thing I would note is that they don't need 100% reliability. They just need sufficient reliablity to make the savings from reuse greater than the cost (payload reduction, landing location operations and repairs etc) of the landing,
* Defined here as attempting to land etiher a landing pad on land or a droneship. I don't count the drop in water tests as landing attempts.
Which you had to do if you wanted to play online or play new games.
To be fair you did at least have the option of opting out and playing your existing games offline which is more than can be said for some of the other cases.
Smart Meters are far more about saving money for the utility company. Unless you're outsourcing to the post office (which is designed for this), sending people out to read everyone's meter is expensive and time consuming when simple telemetry can provide what's needed. They only send people out when they think there might be a problem.
That is the most immediate benefit but I think the real reason is deeper
For the electricity grid to be stable power in needs to match power out. Currently this is achived mostly through supply-side management but that is expensive, it means leaving generation capacity idle most of the time. "use it or lose it" renewables makes the situation worse.
Smart meters give them the technical ability to introduce variable pricing depending on current load. Obviously there is a legal and political side to introducing that too but having the technical capability in place is the first step.
At least the smart meters they are fitting in the UK also have a remote disconnect contactor. This would allow implementation of higher precision blackouts (i.e. a blackout that exempted people who had medical conditions or exempted people who agree to pay more) in the event of an electricity shortage.
There was an old rule-of-thumb in the electrical trades. A million volts won't do anything, but an Amp will kill you.
And it's one of those sayings with a grain of truth in it but which misleads more than it helps.
What actually matters is the current through the body. As a general rule in power systems, a higher voltage means a higher current through the body, the operating current of the system is mostly irrelevent.
I'd hate to see the safety guidelines on a 20,000 (or 50,000) watt connector.
On a three phase system with 230V from phase to neutral and 400V from phase to phase 20kW is about 30 amps per phase. 50kW is about 72A per phase. That's within the range of normal industrial plugs and sockets. For example IEC 60309 connectors come in 16A, 32A, 63A and 125A.
The main thing you have to worry about on high current plugs and sockets is arcing from connection/disconnection under load. The 63A and 125A variants of IEC60309 connectors have a pilot contact that can optionally be used to detect someone trying to unplug the connector and drop the power.
The problem is afaict the marketplace sites model avoids most of the legal protections. Amazon/Ebay get off because they aren't actually the seller or the importer. The seller gets off because they are outside our legal system. Customs don't have the resources to open more than a tiny fraction of incoming packages and there is no reasonable way to tell from the outside of the package whether goods are legitimate or counterfiet.
I'm not sure what the soloution to this is. All the cures I can think of are worse than the disease. Tight regulation of marketplace sites would just drive the buisness to offshore sites that do an even. Having customs open and carefully inspect every small package that comes in would make it virtually impossible to buy stuff from overseas.
Same way it works over gigabit. Data travels as a differential signal within the pairs, power travels as a DC voltage between the pairs.
The real problem with using ethernet as a device interface is that the tradeoff for high speeds over long cheap cables is that the interfaces are realtively expensive and power hungry. This is especially a problem at 10 gigabit speeds.
What bothers me about git is that they don't seem to consider the history of the repository (that is what was on branch "x" of repository "y" on date "z") important. There is the reflog but that seems more geared towards short term disaster recovery than long term history documentation (it's easy to delete entries and afaict there is no way to retrive it for a remote repo) .
In my experiance ram is a big issue with older systems, especially laptops. I have a mid 2007 macbook (so about 8 and a half years old ) that mostly runs linux and I find myself often struggling for ram. I put 4GB of ram in it recently but linux only sees 3GB, presumablly due to some combination of firmware and chipset limitations. It's very easy to bring the machine to the point of grinding swap (running a 64-bit browser probablly doesn't help as it means the browser can keep chewing up memory rather than crashing and being restarted).
While you can do that it's not what the pros usually do. The pros usually run solid core ethernet cable to wallports/patch panels. Then they use readymade patchcords to make the final connections to equipment.
This is a big problem with public transport, providing fast transport to/from the city center is doable but if you have people travelling from one arbitary point in suburbia to another it's virtually impossible to provide a public transport service that is not significantly slower than driving.
https is not perfect but refusing to use it is a serious case of letting perfect be the enemy of good. Furthermore google has been one of the main driving forces behind the introduction of http key pinning which makes it much harder to perform MITM attacks successfully and much more likely that an organisation attempting a MITM attack will be noticed.
Unfortunately the "traditional" ciphersuites establish those keys by having the client generate them and encrypt them with the private key associated the server's certificate. This means that if the private key is later compromised all previous sessions can be decrypted. The DHE and ECDHE cipersuites avoid this problem.
Previously the incumbents were comparing the cost of rolling out a fiber network for homes and small buisnesses to the extra revenue they would get from offering faster speeds. They may also have been worrying about the faster "broadband" services canabalising their dedicated fiber services.
Once Gooogle gets involved in an area the incumbents are comparing the cost of rolling out a fiber based network to the cost of losing customers to Google en-masse. While they are trying to put up legal barriers in Google's way they know that Google is not just some small operation that they can roll right over, so they need to mitigate the damger when Google wins.
Passives aren't really an issue, with only two pins the difference is negliable.
With ICs one sees a fairly distinct line between the large old packages which use imperial pitches (2.54mm 1.27mm) and the small modern packages which use metric pitches (1mm 0.65mm 0.5mm 0.4mm ).
It depends on what level you are doing PCB design at.
At the hobbyist level imperial-based packages like DIL and SOIC dominate but most smaller packages (TQFPs , BGAs, QFNs etc) tend to be metric based. If you have a mixture of components it's usually better to work in metric because a dimension designed in inches can be converted exactly to a terminating decimal fraction in mm while converting the other way can result in a recurring decimal.
Anoyingly some common PCB packages work internally in inch-based measurements regardless of what units they are using for display/entry which leads to strange DRC violations due to rounding errors.
Lets run some rough numbers to see how plausible it is for someone to be forced down a 16 foot wide pipe and spat out the other end.
16 feet is about 5 meters. Lets assume it's a circular pipe with diameter 5m (radius 2.5m) 2.5 squared is about 6 times pi gives us a cross sectional area of about 20 square meters.
An olypic swimmer apparently does about 1.5 meters per second. A diver has flippers which will help make them go faster but they also have a load of gear on their back and they probablly aren't an olympic level swimmer. Lets assume our diver can swim at 1 meter per second (pretty sure this will be an overestimate). If the water flows faster than the diver can swim then the diver will be dragged along with the water flow and spart out the end of the pipe.
! meter per second in out pipe would mean 20 cubic meters of water per second or 72000 cubic meters per hour.
Lete assume the tidal range is 3m (number plucked from averaging the top and bottom of the middle category in the wikipedia article) and assume the tide flows in and out twice per day so it takes 6 hours to completely flow in one direction. To keep the maths simple lets assume that the tide flows in/out at a constant rate. to get 72000 cubic meters per hour would require a surface area of 144000 square meters.
That's a decent sized lake for sure but it doesn't seem implausible to me.
The problem with instant film is it's expensive. The kid may be impressed the first time they see it but they are likely to be less impressed when they find the number of shots they can take is strictly rationed. Pros too appreciate the option of taking multiple shots and only using up expensive consumables for the ones they actually want to print.
Polaroid makes a whole line of instant cameras with film.
Polariod discontinued their own instant film and cameras because they decided it wasn't viable.
A small company called Impossible bought some of the old gear and started production of polariod 100/600 compatible film packs. They had to reinvent much of the chemical process as polariod stopped chemical production years before they stopped film pack production. It seems polariod have started selling the cameras again and are reselling Impossible film.
There is also the pic 300 and pix 300 film which are a rebranding of fuji instax camera and film and some digital products (which I highly suspect are also rebrands though I don't know for sure).
Legal tender means it must be accepted for debts. Many countries make small coins legal tender only for small debts but as I understand it the USA has no such rule.
In most purchases money is directly exchanged for goods without there being a debt so legal tender doesn't apply and the merchants can be as picky about payment methods as they like.
The ACs numbers make no sense, the length of the buffer is irrelevent, what matters is the rate at which you are writing date. 250 megabytes per second is also a crazy datarate, typical broadcast HD is more like 1 megabyte per second (8 megabits per second). Maybe a bit more if you have a cable provider who have more bandwidth than they know what to do with.
1 megabyte per second * 2 tuners = 2 megabytes per second = 7.2 gigabytes per hour ~= 170 gigabytes per day ~= 63 terrabytes per year
The shortest life drive in TFA started showing issues at 300 terrabytes and crapped out after 700 terabytes. So we are talking a probable lifetime of years.
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Why on earth would you think that it is a universal that pubic transport "takes significantly longer to get [where you want to go]"?
My experiance (I live in a major conurbation in the north of the UK and don't drive) is that there are a handful of cases where public transport is faster. Some cities are so congested you don't want to drive into the city center and some of the flagship long distance rail lines run faster than the legal speed limit for cars. If you carefully plan where you live compared to where you work you can get the commute down to a manageable length by making it a single leg journey.
However unless at least one of your origin/destination is in the center of a big city or the two places happen to be on the same public transport route then driving is most likely significantly faster.
During the 2008 crash, SpaceX nearly went under, but was saved by a fixed cost contract to NASA to carry cargo to the International Space Station.
That wasn't the first time NASA had awarded them a contract though, they were also awarded the COTS contract in 2006 to demonstrate commercial orbital transport services.
Since then, most of their launches are for satellites for companies outside the US.
Out of the 23 falcon 9 launches I count 12 where the primary payload was partially or wholly for the US government
2 NASA COTS
8 NASA CRS
1 USAF/NASA/NOAA collaboration
1 NASA/NOAA/CNES
The remaining 11 break down as
1 spacex demo flight
1 payload where the immediate customer was a private canadian company but the final user of the payload was the canadian government.
1 payload for the Turkmenistan National Space Agency
8 flights where the primary payload was communication or broadcast sattelites (sometimes with more than one sattelite per flight)
I agree that spacex is closer to what one would consider a normal private company than ULA but it's also pretty clear that a lot of spacex's revenue comes from the US government and that NASA took a punt on them. When the CRS contract was awarded Falcon 9 had not flown at all and Falcon 1 had only flown test flights.
At least in the US and the UK it's possible to legally fly without a license. To do so your craft has to be very light, in the case of the UK it has to be foot launched and you have to avoid certain airspace. If you want to fly something bigger you need successively tougher licenses. Not much different from the roads really.
I'm mostly thinking of the situation where due to under-investment and the unpredictability of renewables demand sometimes outstrips supply and this is a reasonablly predictable/routine thing.
Without smart meters there is little* incentive for customers to move their electricity consumption to low-demand times and if the supplier does have to resort to cutting customers off they can only include/exclude customers in large blocks. That means the only way they can forciblly reduce consumption is rolling blackouts and they have to be really stingy with who they give out exemptions to since exempting one customer will likely also exempt a bunch arround them.
Having near-realtime metering and a power switch at every customer connection gives them far more options. It may be that variable pricing schemes are enough of a carrot on their own to make people move their consumption to quieter times but if they prove insufficient then rationing schemes would also be possible.
* Some areas have multi-rate conventional meters, but these are a fairly blunt instrument and can only work on long term trends (e.g. day/night), they can't help much with sudden peaks or troughs.
Afaict they have attempted landings* on 6 flights of those two were successful.
Flight 14, failure due to grid fins ran out of hydralic fluid.
Flight 17, failure due to stuck valve
Flight 20, successful landing at the cape
Flight 21, failure due to landing leg issue
Flight 22, failure (and was expected to fail) due to coming in too fast due to a large payload.
Flight 23, successful landing on
So basically the devil is in the details. Each time a failure happens i'm sure they put a lot of effort into working out the details of what went wrong but what is not clear is how many iterations of failure they will have to go through before they get a reliable result.
One thing I would note is that they don't need 100% reliability. They just need sufficient reliablity to make the savings from reuse greater than the cost (payload reduction, landing location operations and repairs etc) of the landing,
* Defined here as attempting to land etiher a landing pad on land or a droneship. I don't count the drop in water tests as landing attempts.
If you upgraded the firmware.
Which you had to do if you wanted to play online or play new games.
To be fair you did at least have the option of opting out and playing your existing games offline which is more than can be said for some of the other cases.
Smart Meters are far more about saving money for the utility company. Unless you're outsourcing to the post office (which is designed for this), sending people out to read everyone's meter is expensive and time consuming when simple telemetry can provide what's needed. They only send people out when they think there might be a problem.
That is the most immediate benefit but I think the real reason is deeper
For the electricity grid to be stable power in needs to match power out. Currently this is achived mostly through supply-side management but that is expensive, it means leaving generation capacity idle most of the time. "use it or lose it" renewables makes the situation worse.
Smart meters give them the technical ability to introduce variable pricing depending on current load. Obviously there is a legal and political side to introducing that too but having the technical capability in place is the first step.
At least the smart meters they are fitting in the UK also have a remote disconnect contactor. This would allow implementation of higher precision blackouts (i.e. a blackout that exempted people who had medical conditions or exempted people who agree to pay more) in the event of an electricity shortage.
There was an old rule-of-thumb in the electrical trades. A million volts won't do anything, but an Amp will kill you.
And it's one of those sayings with a grain of truth in it but which misleads more than it helps.
What actually matters is the current through the body. As a general rule in power systems, a higher voltage means a higher current through the body, the operating current of the system is mostly irrelevent.
I'd hate to see the safety guidelines on a 20,000 (or 50,000) watt connector.
On a three phase system with 230V from phase to neutral and 400V from phase to phase 20kW is about 30 amps per phase. 50kW is about 72A per phase. That's within the range of normal industrial plugs and sockets. For example IEC 60309 connectors come in 16A, 32A, 63A and 125A.
The main thing you have to worry about on high current plugs and sockets is arcing from connection/disconnection under load. The 63A and 125A variants of IEC60309 connectors have a pilot contact that can optionally be used to detect someone trying to unplug the connector and drop the power.
The problem is afaict the marketplace sites model avoids most of the legal protections. Amazon/Ebay get off because they aren't actually the seller or the importer. The seller gets off because they are outside our legal system. Customs don't have the resources to open more than a tiny fraction of incoming packages and there is no reasonable way to tell from the outside of the package whether goods are legitimate or counterfiet.
I'm not sure what the soloution to this is. All the cures I can think of are worse than the disease. Tight regulation of marketplace sites would just drive the buisness to offshore sites that do an even. Having customs open and carefully inspect every small package that comes in would make it virtually impossible to buy stuff from overseas.
Same way it works over gigabit. Data travels as a differential signal within the pairs, power travels as a DC voltage between the pairs.
The real problem with using ethernet as a device interface is that the tradeoff for high speeds over long cheap cables is that the interfaces are realtively expensive and power hungry. This is especially a problem at 10 gigabit speeds.
What bothers me about git is that they don't seem to consider the history of the repository (that is what was on branch "x" of repository "y" on date "z") important. There is the reflog but that seems more geared towards short term disaster recovery than long term history documentation (it's easy to delete entries and afaict there is no way to retrive it for a remote repo) .
In my experiance ram is a big issue with older systems, especially laptops. I have a mid 2007 macbook (so about 8 and a half years old ) that mostly runs linux and I find myself often struggling for ram. I put 4GB of ram in it recently but linux only sees 3GB, presumablly due to some combination of firmware and chipset limitations. It's very easy to bring the machine to the point of grinding swap (running a 64-bit browser probablly doesn't help as it means the browser can keep chewing up memory rather than crashing and being restarted).
Never heard this before and it smells like BS to me, do you have an authoritative source?
While you can do that it's not what the pros usually do. The pros usually run solid core ethernet cable to wallports/patch panels. Then they use readymade patchcords to make the final connections to equipment.
But spouse is downtown, I'm not.
This is a big problem with public transport, providing fast transport to/from the city center is doable but if you have people travelling from one arbitary point in suburbia to another it's virtually impossible to provide a public transport service that is not significantly slower than driving.
https is not perfect but refusing to use it is a serious case of letting perfect be the enemy of good. Furthermore google has been one of the main driving forces behind the introduction of http key pinning which makes it much harder to perform MITM attacks successfully and much more likely that an organisation attempting a MITM attack will be noticed.
Randomised session specific keys are used in tls.
Unfortunately the "traditional" ciphersuites establish those keys by having the client generate them and encrypt them with the private key associated the server's certificate. This means that if the private key is later compromised all previous sessions can be decrypted. The DHE and ECDHE cipersuites avoid this problem.
Previously the incumbents were comparing the cost of rolling out a fiber network for homes and small buisnesses to the extra revenue they would get from offering faster speeds. They may also have been worrying about the faster "broadband" services canabalising their dedicated fiber services.
Once Gooogle gets involved in an area the incumbents are comparing the cost of rolling out a fiber based network to the cost of losing customers to Google en-masse. While they are trying to put up legal barriers in Google's way they know that Google is not just some small operation that they can roll right over, so they need to mitigate the damger when Google wins.
Passives aren't really an issue, with only two pins the difference is negliable.
With ICs one sees a fairly distinct line between the large old packages which use imperial pitches (2.54mm 1.27mm) and the small modern packages which use metric pitches (1mm 0.65mm 0.5mm 0.4mm ).
It depends on what level you are doing PCB design at.
At the hobbyist level imperial-based packages like DIL and SOIC dominate but most smaller packages (TQFPs , BGAs, QFNs etc) tend to be metric based. If you have a mixture of components it's usually better to work in metric because a dimension designed in inches can be converted exactly to a terminating decimal fraction in mm while converting the other way can result in a recurring decimal.
Anoyingly some common PCB packages work internally in inch-based measurements regardless of what units they are using for display/entry which leads to strange DRC violations due to rounding errors.
Lets run some rough numbers to see how plausible it is for someone to be forced down a 16 foot wide pipe and spat out the other end.
16 feet is about 5 meters. Lets assume it's a circular pipe with diameter 5m (radius 2.5m) 2.5 squared is about 6 times pi gives us a cross sectional area of about 20 square meters.
An olypic swimmer apparently does about 1.5 meters per second. A diver has flippers which will help make them go faster but they also have a load of gear on their back and they probablly aren't an olympic level swimmer. Lets assume our diver can swim at 1 meter per second (pretty sure this will be an overestimate). If the water flows faster than the diver can swim then the diver will be dragged along with the water flow and spart out the end of the pipe.
! meter per second in out pipe would mean 20 cubic meters of water per second or 72000 cubic meters per hour.
Lete assume the tidal range is 3m (number plucked from averaging the top and bottom of the middle category in the wikipedia article) and assume the tide flows in and out twice per day so it takes 6 hours to completely flow in one direction. To keep the maths simple lets assume that the tide flows in/out at a constant rate. to get 72000 cubic meters per hour would require a surface area of 144000 square meters.
That's a decent sized lake for sure but it doesn't seem implausible to me.
Yeah, they still exist, used for some niche purposes and as toys for the rich but the internal combustion engine and electric motor now dominate.
The problem with instant film is it's expensive. The kid may be impressed the first time they see it but they are likely to be less impressed when they find the number of shots they can take is strictly rationed. Pros too appreciate the option of taking multiple shots and only using up expensive consumables for the ones they actually want to print.
Polaroid makes a whole line of instant cameras with film.
Polariod discontinued their own instant film and cameras because they decided it wasn't viable.
A small company called Impossible bought some of the old gear and started production of polariod 100/600 compatible film packs. They had to reinvent much of the chemical process as polariod stopped chemical production years before they stopped film pack production. It seems polariod have started selling the cameras again and are reselling Impossible film.
There is also the pic 300 and pix 300 film which are a rebranding of fuji instax camera and film and some digital products (which I highly suspect are also rebrands though I don't know for sure).
Legal tender means it must be accepted for debts. Many countries make small coins legal tender only for small debts but as I understand it the USA has no such rule.
In most purchases money is directly exchanged for goods without there being a debt so legal tender doesn't apply and the merchants can be as picky about payment methods as they like.
The ACs numbers make no sense, the length of the buffer is irrelevent, what matters is the rate at which you are writing date. 250 megabytes per second is also a crazy datarate, typical broadcast HD is more like 1 megabyte per second (8 megabits per second). Maybe a bit more if you have a cable provider who have more bandwidth than they know what to do with.
1 megabyte per second * 2 tuners = 2 megabytes per second = 7.2 gigabytes per hour ~= 170 gigabytes per day ~= 63 terrabytes per year
The shortest life drive in TFA started showing issues at 300 terrabytes and crapped out after 700 terabytes. So we are talking a probable lifetime of years.