I'm in the satellite business myself, and the reality is that satellite capacity is expensive, no matter how you you look at it. As a rough rule of thumb, satellite capacity prices roughly at $6000/MHz/Month. If you do the math, this basically works out to $6-10 per kbps per month, and that's assuming at least a 2 year contract. So if you had a 1Mbps connection with a 4:1 contention ratio, you're still looking at $1500 a month. The economics change a little if you own a whole transponder (Typically a few million dollars a year for 36Mhz), but even then it's not cheap. The only way that DirecWay and the other satellite ISPs can keep their prices within the realm of reason for the average user is by having insane contention ratios, and draconian "Fair Access Policies"
It sucks, but there's not much that will reduce these prices. There are only so many active geosynchronous satellites that can be up there, and there's only a limited amount of spectrum available. Even if SpaceX cuts the launch costs by 80%, the prices won't go down, that just means the satellite operators will be (more) profitable. The end-user pricing is demand driven, not cost driven.
Actually no. Most commercially available hydrogen is produced by steam reformation of methane (natural Gas). Electrolysis of water is far too inefficient to use on a commercial scale.
Oddly, Alaskans actually respect the natural migration of Canadian Geese, and find the entire yearly event a treasure to protect. Shame on the Canadians!
Actually in many places, the geese have become non-migratory. (There are actually several different subspecies, some are prone to finding a comfy spot and just staying there 12 months a year). The resident goose population in the Vancouver area, for example, is huge, and discharging long guns in the heart of the city is probably not the wisest thing to do. Besides, from what I'm told, canada goose tastes horrible.
I wonder why they aren't using gyros with magnetic bearings. Especially in micro-gravity, that could help quite a lot.
We aren't talking about small sensor type devices here. (Attitude sensing is done with laser ring gyros, no moving parts) Reaction wheels are rather large objects and can provide significant force to orient the spacecraft.
Didn't NASA have reaction wheels go on another probe as well? The one we're sending to explore Ceres I think had reaction wheel issues as well and had to be reconfigured to run its mission on thrusters as well.
Reaction wheels a very well known concepts in spaceflight. The ISS uses them to point itself (The Control Moment Gyros) and pretty much any and all geosynchronous satellites also use reaction wheels to keep themselves pointed at earth. This is actually how they ended up recovering Galaxy 15. After several months of drifting while "zombie", the reaction wheels finally saturated (spinning as fast as they could go) causing the satellite to lose earth lock, and go into a safe mode.
Anyhow, the upside and downside is that they are relatively simple devices, and allow for very precise and stable pointing without spending a lot of fuel (you don't want your exhaust condensing on your optics in a telescope now do you?), but at the same time they're mechanical devices, and thus are more fragile than something that's purely solid state.
The configuration change is enabling server certificate validation. If the network is set up for this, all is well: just like SSL, the server demanding the credentials from the client connecting to the network has a certificate, which the client can verify before attempting to authenticate. Spoofing becomes effectively impossible without access to a suitably signed cert.
The fundamental problem you run into however, is that at the point where you need to verify the certificate you don't yet have a network connection. In a PEAP environment, the certificate is presented to the client before layer 3 connectivity has been established. The client obtains the certificate, sees that it has been signed by a valid CA, but it can not actually verify that the certificate is being presented by the right server since, well, there's no network connection yet. It's really one of those chicken and egg problems, there's no good way to resolve it.
The reality is that in most cases, it should pop a warning giving certificate details (along with the fact that it has been signed by a trusted CA), and asking the user if they would like to proceed (and then saving that approval if desired).
I guess you've never been to Monoprice. I use one of their 2.1A car lighter adapters for my iPad, and it works very well. The main issue i have is getting it out of the socket, rather than having it stay in.
While I haven't been camping much, I now have a small (27') sailboat. The one thing I notice is that event though there are lights in the cabin, I'm usually nodding off at around sunset. I do wish I could stay up longer, as in many of these places the stars truly are spectacular (as is the phosphorescence) but alas.:)
These are the people that are generally what's wrong with the world, not what's right.
Fill the plane with Engineers, Computer Scientists, Scientists, Technicians, and the other people who actually make the world work, and you might have something. The only problem is that these people are actually too busy making a living rather than leeching off their employees and customers.
All this is is an excuse to fill an airplane with a lot of self congratulatory reacharounds and hot air.
Easy, don't use imperial cookbooks, try use the republican cookbooks only:)
Little known fact: Many recipes are not directly transferrable between even Canada and the US, even if the proportions are kept correct. This is due to ingredient differences rather than measurement units (In fact, most Canadian cookbooks offer their recipes in both Metric and US). The biggest difference is flour. Canadian flour has a significantly higher gluten content than US "All Purpose" flour, and that can make a huge difference in bread, pastry, and other similar things.
Where L/100km makes an infinite amount of sense is when comparing the fuel efficiency of different vehicles. What is better, upgrading a 35mpg car to 42mpg, or upgrading a 15mpg SUV to one that gets 20mpg? If we look at this in L/100km, it becomes pretty damned easy. The 35mpg car gets 6.72L/100km. Upgrading it to a car that gets 42mpg will mean you're now burning 5.6L/100km, saving approximately 1.1L for every 100km you travel. Conversely, the 15mpg SUV gets 15.68L/100km, while its 20mpg replacement burns 11.76L/100km, a savings of 3.92L for every 100km. So even in the first case, despite increasing your mileage by 7mpg, you're only saving 1.1L, while in the second case you're only increasing your milage by 5mpg, but saving 3.92L.
The fundamental reality here is that for most people, the only time they ever look at the fuel efficiency figures is when they're shopping for a new vehicle. Specifying the fuel usage in L/100km (or hell, Gallons/100mi) provides a much more accurate and useful comparison. The easy solution to your problem is to just publish a number for range. I know that my Jetta gets 725km per tank in city driving, and ~1000 or so in highway driving.
Does anyone have an idea why they're doing this? IIRC the distance to geostationary orbit is bigger than the omne to ground, so why waste energy for that long distance stuff?
They do this so they can have long term communications. If they were doing pure space to ground, you'd need a massive network of ground stations to pickup the station as it goes by. Because the altitude is so low, the patch of ground that the station can see at any one time is actually pretty small (I've bound signals off the ISS's APRS system and hit Saskatchewan from BC, but that's pushing it). This is hard enough on land, but never mind the fact that much of the earth it flies over is made out of water.:)
Instead, they go up to the TDRSS satellites (also used by the shuttle when it was flying, Hubble, and various other low orbit satellites). This means that the station only needs to hand off 3 or 4 times an orbit, rather than every 10 minutes, and means that you only need 3 ground stations to support it (Any given Geosynchronous satellite can see approximately 120 degrees of the earth).
There are gaps in coverage, but not actually due to the TDRSS constellation per se, rather it's because of where the antenna onboard the station is located. In certain parts of the orbit, the antenna's view of the satellite is blocked by variou sstructures onboard the ISS (They can't shoot through the solar wings, heat exchangers, etc...)
Do you have any insight why they even bother with TB when 10Gb Ethernet already exists and has been deployed for ages? I.e. why not just use 10GbE instead? It seems like reinventing the wheel for no real gain.
When all you have is a hammer...
The main reason for using Thunderbolt over 10Gb Ethernet is that one has a fairly significant protocol overhead (Ethernet) while the other is primarily a bus protocol, and operates at a much lower level than Ethernet does. Each has their strengths and weaknesses, each has their application.
Also has an atmosphere, which makes landing a lot easier and cheaper, and an average temperature that our equipment can deal with.
Actually, the Martian atmosphere is a huge hinderance, and one of the reasons why so many missions have failed. The fundamental problem is that Mars has just enough atmosphere that you need to deal with it (heat shields, atmospheric entry, etc...) but not enough to actually be useful for anything. This is how you end up with rube-goldbergesque landing systems like what MSL used.
Landing on a planetary body without an atmosphere is actually much simpler, as you can just do a pure rocket descent. May not be as efficient, but it is certainly easier, hell they landed the NEAR Shoemaker probe on the asteroid it was orbiting, and it wasn't even designed to land (of course, the gravity on an asteroid is weak enough that you could throw a baseball on an escape trajectory, but that's another matter). The most obvious example, of course, is the Moon landings. The moon has effectively no atmosphere of any kind, yet the incredibly lightweight and delicate LEM was able to land on the surface and return to orbit with aplomb.
Seriously, this is one of them. I love the idea of sharing and all, but we can wait to see your vacation or...other... pics more than 15 minutes after you take it. A camera does not need to be directly connected to the internet, and all it does is open up potential security flaws. Find a good way to remotely exploit this and next thing you know, you can just take a vacation vicariously, through someone's (unsuspecting) lens. With the way tablets, smartphones etc are going, they can be great and (more) secure gateways to posting things, plus it gives you the chance to *filter* your photos...
As I mentioned above, the real point of the wifi link is NOT for sharing the photos. It's to remote control the camera so that you can either control it without touching it (say when doing astro-photography, where simply touching the camera will throw your whole system out of whack), doing tasks that you can't do hands on (Focus micro-adjustments, highly useful when doing product photography), or controlling the camera when it is placed in an otherwise inaccessible location.
The other main use for the wireless dump capability is in the studio... Mom and dad are getting pictures taken of the kids & dog, and this capability allows the photog to dump the photos in real-time to a neighbouring computer, so they can see exactly what's coming out. In either case, the camera itself isn't typically "on the internet"
The (wrong) assumption by Canon is that the camera will only be used on private networks, since in professional situations, that's normally what you would have anyhow.
For example, I frequently find myself using my 10-22mm EF-Szoom lens. Canon's EF equivalent, after compensating for the 1.6x crop, is the 16-35. The 10-22 EF-S costs about $720. The 16-35 costs a jaw-dropping $1450.
Yes, and optically, the 10-22 is much easier to make, and requires less precision than the 16-35. You're also comparing a consumer grade lens (the 10-22) with L glass. They're two completely different classes of lenses, with completely different performance metrics. It's not just the focal length, but the resolution, flare control (especially at these focal lengths), build quality, and materials.
eye-fi sd cards, on the other hand, start at about 30-35 bucks... and cameras with built-in networking features, start at less than 100..
Sure, but you also fail to realize the point of the wifi/networking for the Canon DSLRs. It isn't just about dumping your photos off the camera in real-time, it also provides full remote control of the camera. For the average consumer, this doesn't mean much, but in certain parts of the professional world, this is a huge deal. Take, for example, an architectural photographer taking a picture of a tight space (say the inside of a bathroom). Remote contorl over the camera lets them stuff the camera into a corner, or some inconspicuous spot, and then set the exposure, focus, etc... from outside the room, thus keeping them out of the picture.
Same thing goes for product photography, though more due to the fine control over the focus you get. Using the remote capture application, you can micro-nudge the focus and see the results live on the display. It's an incredible advance over film, and even earlier digital cameras. Admittedly, most of this can be done over USB, but Wifi/network is the natural progression of this.
Speaking of which, it's more than just opening the gates at day, and shutting them at night. They literally spend power at night to PUMP WATER UPHILL into the reservoir. They treat it like a battery. Not great efficiency, but AMAZING capacity. And hey, coupled with nukie plants which like to run at steady rates, it's a great match.
In BC, at least, there's no pump and store capability at any of the hydro-electric plants, mainly because there's a) no need, and b) no source of water to pump. The dams are all on rivers, and when the water flows out of them, it does what water always does, and goes down the river. The flip side to this is that the catchment area for the reservoir is so huge that it's not that big of a deal.
Why can't nuclear power stand alone, out of curiosity?
Nuclear power can't stand alone, at least with current reactor designs, because their output can't be ramped up or down very quickly. Many areas of North America (California is an example I know best) exhibit extreme daytime load peaks, followed by deep night-time lulls, due to the air conditioning load.
Years ago, during the California power crisis, BC Hydro made a killing due to this effect. During the daytime, they would run their hydro-electric plants flat out, at completely unsustainable levels, and sell the power to California utilities at almost usurious rates. At night, they would shut the hydro plants down, allow the water to pool up again behind the dam, and buy dirt cheap nuclear power from California.
The real point is that while Nuclear can work for the baseline load on the grid, current designs simply aren't nimble enough to meet the peaks and valleys they would face in normal day to day operation. They need to be complimented with some other power source that is more nimble.
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I'm in the satellite business myself, and the reality is that satellite capacity is expensive, no matter how you you look at it. As a rough rule of thumb, satellite capacity prices roughly at $6000/MHz/Month. If you do the math, this basically works out to $6-10 per kbps per month, and that's assuming at least a 2 year contract. So if you had a 1Mbps connection with a 4:1 contention ratio, you're still looking at $1500 a month. The economics change a little if you own a whole transponder (Typically a few million dollars a year for 36Mhz), but even then it's not cheap. The only way that DirecWay and the other satellite ISPs can keep their prices within the realm of reason for the average user is by having insane contention ratios, and draconian "Fair Access Policies"
It sucks, but there's not much that will reduce these prices. There are only so many active geosynchronous satellites that can be up there, and there's only a limited amount of spectrum available. Even if SpaceX cuts the launch costs by 80%, the prices won't go down, that just means the satellite operators will be (more) profitable. The end-user pricing is demand driven, not cost driven.
Actually no. Most commercially available hydrogen is produced by steam reformation of methane (natural Gas). Electrolysis of water is far too inefficient to use on a commercial scale.
Oddly, Alaskans actually respect the natural migration of Canadian Geese, and find the entire yearly event a treasure to protect. Shame on the Canadians!
Actually in many places, the geese have become non-migratory. (There are actually several different subspecies, some are prone to finding a comfy spot and just staying there 12 months a year). The resident goose population in the Vancouver area, for example, is huge, and discharging long guns in the heart of the city is probably not the wisest thing to do. Besides, from what I'm told, canada goose tastes horrible.
They are Canadian Geese so the Constitution doens't apply
Eh? They're loud, obnoxious, and leave shit everywhere. Clearly they're American. ;)
I wonder why they aren't using gyros with magnetic bearings. Especially in micro-gravity, that could help quite a lot.
We aren't talking about small sensor type devices here. (Attitude sensing is done with laser ring gyros, no moving parts) Reaction wheels are rather large objects and can provide significant force to orient the spacecraft.
Didn't NASA have reaction wheels go on another probe as well? The one we're sending to explore Ceres I think had reaction wheel issues as well and had to be reconfigured to run its mission on thrusters as well.
Reaction wheels a very well known concepts in spaceflight. The ISS uses them to point itself (The Control Moment Gyros) and pretty much any and all geosynchronous satellites also use reaction wheels to keep themselves pointed at earth. This is actually how they ended up recovering Galaxy 15. After several months of drifting while "zombie", the reaction wheels finally saturated (spinning as fast as they could go) causing the satellite to lose earth lock, and go into a safe mode.
Anyhow, the upside and downside is that they are relatively simple devices, and allow for very precise and stable pointing without spending a lot of fuel (you don't want your exhaust condensing on your optics in a telescope now do you?), but at the same time they're mechanical devices, and thus are more fragile than something that's purely solid state.
The configuration change is enabling server certificate validation. If the network is set up for this, all is well: just like SSL, the server demanding the credentials from the client connecting to the network has a certificate, which the client can verify before attempting to authenticate. Spoofing becomes effectively impossible without access to a suitably signed cert.
The fundamental problem you run into however, is that at the point where you need to verify the certificate you don't yet have a network connection. In a PEAP environment, the certificate is presented to the client before layer 3 connectivity has been established. The client obtains the certificate, sees that it has been signed by a valid CA, but it can not actually verify that the certificate is being presented by the right server since, well, there's no network connection yet. It's really one of those chicken and egg problems, there's no good way to resolve it.
The reality is that in most cases, it should pop a warning giving certificate details (along with the fact that it has been signed by a trusted CA), and asking the user if they would like to proceed (and then saving that approval if desired).
I guess you've never been to Monoprice. I use one of their 2.1A car lighter adapters for my iPad, and it works very well. The main issue i have is getting it out of the socket, rather than having it stay in.
While I haven't been camping much, I now have a small (27') sailboat. The one thing I notice is that event though there are lights in the cabin, I'm usually nodding off at around sunset. I do wish I could stay up longer, as in many of these places the stars truly are spectacular (as is the phosphorescence) but alas. :)
... I voted for Kodos.
I always thought that "Canada Geese" should really be called "American Geese"... They're loud, obnoxious, and leave shit everywhere. ;)
These are the people that are generally what's wrong with the world, not what's right.
Fill the plane with Engineers, Computer Scientists, Scientists, Technicians, and the other people who actually make the world work, and you might have something. The only problem is that these people are actually too busy making a living rather than leeching off their employees and customers.
All this is is an excuse to fill an airplane with a lot of self congratulatory reacharounds and hot air.
Chickens used to be Red Junglefowls (Gallus gallus). Just saying.
Sure, but which laid the egg first? the Chicken or the Junglefowl?
Easy, don't use imperial cookbooks, try use the republican cookbooks only :)
Little known fact: Many recipes are not directly transferrable between even Canada and the US, even if the proportions are kept correct. This is due to ingredient differences rather than measurement units (In fact, most Canadian cookbooks offer their recipes in both Metric and US). The biggest difference is flour. Canadian flour has a significantly higher gluten content than US "All Purpose" flour, and that can make a huge difference in bread, pastry, and other similar things.
I prefer God's one true screw: The Robertson.
Where L/100km makes an infinite amount of sense is when comparing the fuel efficiency of different vehicles. What is better, upgrading a 35mpg car to 42mpg, or upgrading a 15mpg SUV to one that gets 20mpg? If we look at this in L/100km, it becomes pretty damned easy. The 35mpg car gets 6.72L/100km. Upgrading it to a car that gets 42mpg will mean you're now burning 5.6L/100km, saving approximately 1.1L for every 100km you travel. Conversely, the 15mpg SUV gets 15.68L/100km, while its 20mpg replacement burns 11.76L/100km, a savings of 3.92L for every 100km. So even in the first case, despite increasing your mileage by 7mpg, you're only saving 1.1L, while in the second case you're only increasing your milage by 5mpg, but saving 3.92L.
The fundamental reality here is that for most people, the only time they ever look at the fuel efficiency figures is when they're shopping for a new vehicle. Specifying the fuel usage in L/100km (or hell, Gallons/100mi) provides a much more accurate and useful comparison. The easy solution to your problem is to just publish a number for range. I know that my Jetta gets 725km per tank in city driving, and ~1000 or so in highway driving.
Does anyone have an idea why they're doing this? IIRC the distance to geostationary orbit is bigger than the omne to ground, so why waste energy for that long distance stuff?
They do this so they can have long term communications. If they were doing pure space to ground, you'd need a massive network of ground stations to pickup the station as it goes by. Because the altitude is so low, the patch of ground that the station can see at any one time is actually pretty small (I've bound signals off the ISS's APRS system and hit Saskatchewan from BC, but that's pushing it). This is hard enough on land, but never mind the fact that much of the earth it flies over is made out of water. :)
Instead, they go up to the TDRSS satellites (also used by the shuttle when it was flying, Hubble, and various other low orbit satellites). This means that the station only needs to hand off 3 or 4 times an orbit, rather than every 10 minutes, and means that you only need 3 ground stations to support it (Any given Geosynchronous satellite can see approximately 120 degrees of the earth).
There are gaps in coverage, but not actually due to the TDRSS constellation per se, rather it's because of where the antenna onboard the station is located. In certain parts of the orbit, the antenna's view of the satellite is blocked by variou sstructures onboard the ISS (They can't shoot through the solar wings, heat exchangers, etc...)
Do you have any insight why they even bother with TB when 10Gb Ethernet already exists and has been deployed for ages? I.e. why not just use 10GbE instead?
It seems like reinventing the wheel for no real gain.
When all you have is a hammer...
The main reason for using Thunderbolt over 10Gb Ethernet is that one has a fairly significant protocol overhead (Ethernet) while the other is primarily a bus protocol, and operates at a much lower level than Ethernet does. Each has their strengths and weaknesses, each has their application.
Also has an atmosphere, which makes landing a lot easier and cheaper, and an average temperature that our equipment can deal with.
Actually, the Martian atmosphere is a huge hinderance, and one of the reasons why so many missions have failed. The fundamental problem is that Mars has just enough atmosphere that you need to deal with it (heat shields, atmospheric entry, etc...) but not enough to actually be useful for anything. This is how you end up with rube-goldbergesque landing systems like what MSL used.
Landing on a planetary body without an atmosphere is actually much simpler, as you can just do a pure rocket descent. May not be as efficient, but it is certainly easier, hell they landed the NEAR Shoemaker probe on the asteroid it was orbiting, and it wasn't even designed to land (of course, the gravity on an asteroid is weak enough that you could throw a baseball on an escape trajectory, but that's another matter). The most obvious example, of course, is the Moon landings. The moon has effectively no atmosphere of any kind, yet the incredibly lightweight and delicate LEM was able to land on the surface and return to orbit with aplomb.
Seriously, this is one of them. I love the idea of sharing and all, but we can wait to see your vacation or ...other... pics more than 15 minutes after you take it. A camera does not need to be directly connected to the internet, and all it does is open up potential security flaws. Find a good way to remotely exploit this and next thing you know, you can just take a vacation vicariously, through someone's (unsuspecting) lens. With the way tablets, smartphones etc are going, they can be great and (more) secure gateways to posting things, plus it gives you the chance to *filter* your photos...
As I mentioned above, the real point of the wifi link is NOT for sharing the photos. It's to remote control the camera so that you can either control it without touching it (say when doing astro-photography, where simply touching the camera will throw your whole system out of whack), doing tasks that you can't do hands on (Focus micro-adjustments, highly useful when doing product photography), or controlling the camera when it is placed in an otherwise inaccessible location.
The other main use for the wireless dump capability is in the studio... Mom and dad are getting pictures taken of the kids & dog, and this capability allows the photog to dump the photos in real-time to a neighbouring computer, so they can see exactly what's coming out. In either case, the camera itself isn't typically "on the internet"
The (wrong) assumption by Canon is that the camera will only be used on private networks, since in professional situations, that's normally what you would have anyhow.
For example, I frequently find myself using my 10-22mm EF-Szoom lens. Canon's EF equivalent, after compensating for the 1.6x crop, is the 16-35. The 10-22 EF-S costs about $720. The 16-35 costs a jaw-dropping $1450.
Yes, and optically, the 10-22 is much easier to make, and requires less precision than the 16-35. You're also comparing a consumer grade lens (the 10-22) with L glass. They're two completely different classes of lenses, with completely different performance metrics. It's not just the focal length, but the resolution, flare control (especially at these focal lengths), build quality, and materials.
eye-fi sd cards, on the other hand, start at about 30-35 bucks... and cameras with built-in networking features, start at less than 100..
Sure, but you also fail to realize the point of the wifi/networking for the Canon DSLRs. It isn't just about dumping your photos off the camera in real-time, it also provides full remote control of the camera. For the average consumer, this doesn't mean much, but in certain parts of the professional world, this is a huge deal. Take, for example, an architectural photographer taking a picture of a tight space (say the inside of a bathroom). Remote contorl over the camera lets them stuff the camera into a corner, or some inconspicuous spot, and then set the exposure, focus, etc... from outside the room, thus keeping them out of the picture.
Same thing goes for product photography, though more due to the fine control over the focus you get. Using the remote capture application, you can micro-nudge the focus and see the results live on the display. It's an incredible advance over film, and even earlier digital cameras. Admittedly, most of this can be done over USB, but Wifi/network is the natural progression of this.
Speaking of which, it's more than just opening the gates at day, and shutting them at night. They literally spend power at night to PUMP WATER UPHILL into the reservoir. They treat it like a battery. Not great efficiency, but AMAZING capacity. And hey, coupled with nukie plants which like to run at steady rates, it's a great match.
In BC, at least, there's no pump and store capability at any of the hydro-electric plants, mainly because there's a) no need, and b) no source of water to pump. The dams are all on rivers, and when the water flows out of them, it does what water always does, and goes down the river. The flip side to this is that the catchment area for the reservoir is so huge that it's not that big of a deal.
Why can't nuclear power stand alone, out of curiosity?
Nuclear power can't stand alone, at least with current reactor designs, because their output can't be ramped up or down very quickly. Many areas of North America (California is an example I know best) exhibit extreme daytime load peaks, followed by deep night-time lulls, due to the air conditioning load.
Years ago, during the California power crisis, BC Hydro made a killing due to this effect. During the daytime, they would run their hydro-electric plants flat out, at completely unsustainable levels, and sell the power to California utilities at almost usurious rates. At night, they would shut the hydro plants down, allow the water to pool up again behind the dam, and buy dirt cheap nuclear power from California.
The real point is that while Nuclear can work for the baseline load on the grid, current designs simply aren't nimble enough to meet the peaks and valleys they would face in normal day to day operation. They need to be complimented with some other power source that is more nimble.
And what if you need to split a quart 100 ways? then you're pooched worse than if you were using metric.