My experiences with comcast have been very mixed. In 4 years of use it never seems to go down! Speeds are really good. Technically they seem really good.
But their customer support is just awful. I've been trying on anf off for years to hookup to their news server. The info page first suggests you use their plain NS. But it's slow and doesnt carry many oddball goups I'd like to receive. If you call them up, they'll point you to their enhanced "giganews" server. Well no, they always give you the wrong ip name for the server the first time. The giganews info page also lists the wrong name. If you call enough times, they will find the right name and tell you. But they don't fix their info page even when you call multiple times. Not for 3 years at least. And then the server seems configured funny, as neither Outlook Expres or Firefox works with it without setting a bunch of strange options. It shouldnt be this hard!
Also they change their home page look about every week, so you have to go and hunt for the "email" button weekly. Sigh.
JK's invention was more like what's known as a "hybrid" Ic, with little parts hooked together with very fine wires. It was Noyce at Fairchild that invented what is the "IC"-- a planar silicon device, with the components etched and diffused onto the surface. No discrete wires, no discrete components.
See JK's patent 3,138,743 for details.
>You do realize that TCP checksumming on a 1Gbit ethernet link takes about 1GHz worth of CPU power?
It's been a few years since I worked on TCP checksum routines, but IIRC on a Pentium you can interleave two 32-bit checksum ops, filling up the ol U and V pipes. Unroll the loop a few times and the code runs faster than memory can fetch.
But you're correct-- this is an excellent example where a very little hardware (NOT another CPU!), can free up a CPU from humdrum additions. But most ethernet chips already have built-in checksumming hardware, so it's a bit OT.
Oh, and their cheapness made for one advantage-- you could have a stealth network: They saved a few sheckels by deriving the on-board ethernet clock from the CPU clock. Which means if you overclock the CPU, the ethernet timing speeds up too! That means you can set up a bunch of these PC's and using relatively dumb network hubs, have a stealth network. Other PC's see these packets as bad packets, as they can't sync to the data. Any PC's running at similar speeds can see the packets. Just like having your own private network. Kewl squared!
This is yet another round of the GCMOH. Anytime there are idlle hardware engineers they find something that can be moved off the main CPU to hardware (or these days, almost always, another processor). This is almost always a bad idea:
Erecting yet another edifice brings on the huge and unavoidable overheads of yet another different CPU instruction set, yet another real-time scheduler, another code base, another set of performance and timing bottlenecks. Another group of programmers. Another set of in-circuit emulators, debugging tools, and system kernel. Another cycle of testing, bug fixes, updates.
It sets up a split in the programming team-- there's now much more reason for finger-pointing and argument and mistrust.
The extra money would usually buy you another CPU and lots of RAM, resources that would benefit every part of the system, not just the network I/O.
The separate I/O processor usually requires the geekiest and least communicative of the programmers-- not a good thing. The manuals for the I/O card are likely to be very brief and sketchy, and rarely up to date.
The I/O processor is almost always at least one generation of silicon technology older than the CPU, so even though the glossy brochures just drip with Speeeed! and Vrooom!-y adjectives, it's not that speedy in comparison to the CPU.
For examples, see the $4000 graphics co-processor that IBM tried to sell for the PC (IIRC the CPU could outdo-it). The various disk-compression cards for the PC. Also see the serial ports on the Mac IIvx (very expensive and not noticeably better). Don't forget the P-code chip for the PDP-11/03. All very expensive and blase' performance/$.
Not so long ago I got on a Beowulf kick and bought TEN Amptron motherboards (made by ECS, Amptron just added a sticker). The Beowulf idea never got rolling, but I've sinced installed seven of the motherboards in other computer cases. Not a single problem with any of them.
One big problem with his report is he didnt know that:
It wasnt a deliberate, precise and selective strike.
Nagasaki wasnt the primary intended target. The intended target was Kokura, but the spotter planes that went ahead found it to be completely socked in with clouds, so the bomb plane diverted to their secondary target, Nagasaki.
Nagasaki too was almost completely clouded over, but of course they were anxious to drop the bomb, so they aimed by using radar, which was very poor in those days, and they were WAY OFF, like miles from the intended aiming point. A lot of the blast was lost in the hills.
Not a red-letter day for the USAF. Most of this info was casually surpressed at the time.
>Assuming the craft doesn't trade any kinetic for gravitational potential energy.
I don't think it has any choice.
>, it could speed up by 1600 m/s in a year
But escape veliocity is about 1.4 times orbital velocity, so it's going to take let's see-- 7500 m/s * 1.4 - 7500, wow only about 2 years!
Of course this is just the acceleration of the sail, if the satellite package has any mass, you're going to have to add more sail to help drag that along.
Did a little back of the spreadsheet calculation.
If you take thr trhrust numbers fomr the article, you get a kilogram of thrust from every square kilometer. That's a millionth of a Kg from every square meter. Or a thousandth of a gram. If you assume the sail weighs.1 gram per square meter, that's an acceleration of 1/100th of a G. Not terribly impressive. Certainly not enough to push anything out of earth orbit. And a very slow way to tour the solar system. And what do you do at night?:)
Sorry to be such a Grumpy Gus about this. I have plenty of respect for the people and projects. tht's not the issue. The issue in my mind is that history has shown that human nature has a strong tendency to ignore, deflect, and even mislead when it comes to investigating mistakes and misdeeds. In soooo many cases, the real extent of the problems have been minimized and downplayed, often by huge factors. Just one example from this subject-- the Oak Ridge Boys would take water samples from the creek, and measure the mercury concentation with various extremely inadequate devices and processes. Everything measured jsut fine! Then a local yokel happened to mention "Ahem, but you can SEE actual droplets of mercury on the creek bottom!" "Ohhhhh, we're not instructed to take BOTTOM samples!".
The tendency in any big organization is of course, to keep the organization going at all costs. So there's every effort made to not see the problems, to fund studies that will look in the wrong places, to classify studies as "national security" that look bad, to mandate reforms that are never funded, to implement token cleanups, you all know the drill.
For example, as to actual cleanups, googling shows very little going on. Some mercury was removed from a sump. A big story in the paper about "cleanup finished", if you read the fine print, reveals that only 1/100th of the estimated $ amount was funded, and eventually only 13 acres had some lacadaisical scraping. And the scraped dirt wasnt cleaned! It was just moved to another site.
Now maybe a HUGE cleanup was done, but funny that Google doesnt catch it, and the DOE didnt publicize it.
It's nothing personal, but I just hate to see all the BS the still surrounds issues like these.
Regards,
A_H
More BS!
Please explain how they're cleaning up the mercury in the soil and water and sediments. AFAIK there's no way to do so. Do they have the whole creek roped off? The one estimate I've seen says 500 lbs per year are washing off into the creek. That's still an awful lot.
Seeing as there are advisories many places about eating lake fish that have excessive mercury form power plant emissions, what are the advisories about fishing in the Oak ridge area? What are the mercury levels in the fish? 776K tons of mercury is a whole lot.
BTW the foolish things with mercury were in the 1950's, not during WWII, so the hot-war excuse is not applicable.
Oh yes, Japan and France, go to it! Never mind the laws of Physics! All those equations with squares, cubes and quad powers in them-- ignore them. All the experience with the Concorde, The Blackbird, the Valkrie, the B-58-- just ignore how expensive it is to build and maintain an airplane made out of Titanium. Also ignore how much fuel it takes to push a big plane through the air at that speed, with the air resistance going up as the fourth power of the speed. And how you're carrying most of the fuel halfway around the world, at air-mail rates. And doing so over an Artic route, with not a chance at a safe landing or a prompt rescue. That's JUST what the US air industry needs, having you go off on some hopeless quest.
This may bell be just a PR campaign to make the place look better. Lots of things you won't hear on the tour:
The calutrons were basically a FAILURE-- they only put out about 10% of the expected U235-- the rest they smeared all over the place, and not in the collection bucket. Once the gas diffusion plant got running the calutrons were relegated to secondary status. Being extremely expensive and inefficient to boot, they were shut down ASAP after the war.
They were built mostly due to Lawrence's reputation in building the cyclotron, not on any technical merit.
Ask about when the building had most of the world's mercury flowing through its pipes. And how much got lost. A DOE report says: "A 1983 study by USDOE estimates that 733,000 pounds of elemental mercury were released to the environment in the 1950s and 1960s around the Y-12 Plant. Most of the contamination around Y-12 is confined to the upper 10 feet of soils and fill. Additional studies revealed that some 170,000 pounds of mercury are contained in the sediments and floodplain of about a 15-mile length of East Fork Poplar Creek (EFPC), which has its headwaters at Y-12, and that some 500 pounds of mercury annually leave this watershed." ( i.e.: don't smoke the grass)
Ask about the nearby sites where they dumped tons of radioactive waste right into the creeks and hollers.
Just MHO but his would be one of the LAST places on Earth I'd care to visit.
A scroll wheel is really cheap, it's just like the roll sensors, only turned upwards. Maybe 50 cents added cost.
A scroll panel is a much more comlex device, with a capacitive or resistive transducer, x-y driving and sensing electronics, and a/d converters. Several $ I'd guess.
By the time these costs go up the manufactiring and distribution and retail paths, we're up to many $ difference. It's hard to see paying that much more for a solution to a non-problem.
Energy savings, WHAT energy savings? Charging a battery is not 100% efficient, discharging it even less so. The only saving comes from the supossedly smaller and lighter gas engine.
Ahem, I'm not the one quoting marketing documents, you are.
A 8 year guaratee isnt that great, if it's your typical pro-rated battery warranty. After 4 years you're down to half the original warranty, dropping down to zero after 8 years.
AFAIK the hybrid car makers don't have any special NiMH magic batteries. All rechargeable batteries lose a little capacity on each and every charge/discharge cycle. The best NiMH's seem to be good for 500 to 1000 full cycles. Now maybe hybrid vehicles get more cycles if they don't discharge the cells too deeply. But eventually the cells *will* need replacing, and the piper must be paid. And the cost isnt peanuts either. If we assume the cost will come down to $10K, that's still another 10 cents a mile of hidden cost.
I'm not sure hybrid cars are the answer. You use somewhat less gas, but every few years you need a new set of batteries. Batteries are typically toxic stews of lead, sulfuric acid, or nickel and cadmium.
Also all the energy that went into making existing cars is wasted if the old cars get prematurely scrapped.
Methinks this is more of the traditional brainwashing to get Japanese to buy more and newer things to stimulate a sagging economy.
Peeeple, TFA doesnt give much detail, but IMHO it's not a transistor, it's more like a very slow switch.
And there's not much use for a switch that small-- individual molecules arent and cant be made reliable enough. just your basic room temperature heat is enough to disrupt these things due to normal diffusion. Just one weak cosmic ray and the whole thing is toast.
think of it more as a geeky parlor trick, nothing more.
What a triple-stinkin load of Wolframmy fermeted bollocks!
A triple load:
First, we twiddled with x's and y's until our formula, developed by us, and nobody else, kinda matches the real-world data. Our formula.
Next, we conclude by looking at our cooked-up formula, the real-world follows our rule! Brilliant! We congratulate ourselves. Several times. With good Spanish wine.
Finally, we expand: other things must work the same way! Boy, we must be really brilliant! Better start ironing my Noble-prize ballgown!
Richard Feynman has been over this ground. He once read some medical article that concluded that iron was responsible for fevers. You see he took his sick wife's temperature, plotted the fever curve, then looked in a chemistry book for a reaction that matched that curve. Some iron reaction matched the best, therefore he triumphantly concluded that iron caused fevers.
Same thing, different decade. We have gotten not a whit wiser in fifty years.
Well, not to get into a flame war, but I just did a Google search on "the sprit is willing". The actual phrase it turns out is "the spirit is indeed willing". Which showcases the other downfall of phrase-matching-- just one inserted word that doesnt change the meaning or horribly inverts the meaning will trip up any dumb phrase matcher. For example, the google matcher is more likely to glom onto the soap opera "The spirit is willing", rather than the exact biblical verse "the spirit is indeed willing". Or if the extra word is somehing negatory, or sarcastic, like "the spirit is NOT willing", or "The spirit is like bodaciously willing". It's unlikely that every possible permutation with 1,2,3,4 added adjectives or adverbs is going to be found in text somewhere, so there are going to be a lot of non-matches or mismatches. JMHO.
Sorry, you're just babbling generalities. let's look at the facts:
the only hard fact we can discern is from Carnot's principles, the turbine is going to run at about 2% efficiency. You can't even pay the interest cost on the turbine with that low an efficiency.
The other factoid is the 2Km-long test pipe cost $11M. Generously assuming there's 100 MW of heat going thru the pipe, at 2% efficiency thats 2 megawatts of electricity, which is only about $50/hr's worth, or $450,000 per year. Assume you need 5 employees at $50K/yr, that eats up 250K of your profit.
It's hard to pay off a $11M loan when your income is less than one tenth the interest cost.
Yep, go look. Not a single number that I could find. In their Q & A section, they pose the question "What's the efficiency?" then they babble and never answer the question. Hmmmm....
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My experiences with comcast have been very mixed. In 4 years of use it never seems to go down! Speeds are really good. Technically they seem really good. But their customer support is just awful. I've been trying on anf off for years to hookup to their news server. The info page first suggests you use their plain NS. But it's slow and doesnt carry many oddball goups I'd like to receive. If you call them up, they'll point you to their enhanced "giganews" server. Well no, they always give you the wrong ip name for the server the first time. The giganews info page also lists the wrong name. If you call enough times, they will find the right name and tell you. But they don't fix their info page even when you call multiple times. Not for 3 years at least. And then the server seems configured funny, as neither Outlook Expres or Firefox works with it without setting a bunch of strange options. It shouldnt be this hard! Also they change their home page look about every week, so you have to go and hunt for the "email" button weekly. Sigh.
JK's invention was more like what's known as a "hybrid" Ic, with little parts hooked together with very fine wires. It was Noyce at Fairchild that invented what is the "IC"-- a planar silicon device, with the components etched and diffused onto the surface. No discrete wires, no discrete components. See JK's patent 3,138,743 for details.
>You do realize that TCP checksumming on a 1Gbit ethernet link takes about 1GHz worth of CPU power? It's been a few years since I worked on TCP checksum routines, but IIRC on a Pentium you can interleave two 32-bit checksum ops, filling up the ol U and V pipes. Unroll the loop a few times and the code runs faster than memory can fetch. But you're correct-- this is an excellent example where a very little hardware (NOT another CPU!), can free up a CPU from humdrum additions. But most ethernet chips already have built-in checksumming hardware, so it's a bit OT.
Oh, and their cheapness made for one advantage-- you could have a stealth network: They saved a few sheckels by deriving the on-board ethernet clock from the CPU clock. Which means if you overclock the CPU, the ethernet timing speeds up too! That means you can set up a bunch of these PC's and using relatively dumb network hubs, have a stealth network. Other PC's see these packets as bad packets, as they can't sync to the data. Any PC's running at similar speeds can see the packets. Just like having your own private network. Kewl squared!
- Erecting yet another edifice brings on the huge and unavoidable overheads of yet another different CPU instruction set, yet another real-time scheduler, another code base, another set of performance and timing bottlenecks. Another group of programmers. Another set of in-circuit emulators, debugging tools, and system kernel. Another cycle of testing, bug fixes, updates.
- It sets up a split in the programming team-- there's now much more reason for finger-pointing and argument and mistrust.
- The extra money would usually buy you another CPU and lots of RAM, resources that would benefit every part of the system, not just the network I/O.
- The separate I/O processor usually requires the geekiest and least communicative of the programmers-- not a good thing. The manuals for the I/O card are likely to be very brief and sketchy, and rarely up to date.
- The I/O processor is almost always at least one generation of silicon technology older than the CPU, so even though the glossy brochures just drip with Speeeed! and Vrooom!-y adjectives, it's not that speedy in comparison to the CPU.
For examples, see the $4000 graphics co-processor that IBM tried to sell for the PC (IIRC the CPU could outdo-it). The various disk-compression cards for the PC. Also see the serial ports on the Mac IIvx (very expensive and not noticeably better). Don't forget the P-code chip for the PDP-11/03. All very expensive and blase' performance/$.Not so long ago I got on a Beowulf kick and bought TEN Amptron motherboards (made by ECS, Amptron just added a sticker). The Beowulf idea never got rolling, but I've sinced installed seven of the motherboards in other computer cases. Not a single problem with any of them.
Regards, A_H
Nagasaki wasnt the primary intended target. The intended target was Kokura, but the spotter planes that went ahead found it to be completely socked in with clouds, so the bomb plane diverted to their secondary target, Nagasaki.
>Assuming the craft doesn't trade any kinetic for gravitational potential energy. I don't think it has any choice. >, it could speed up by 1600 m/s in a year But escape veliocity is about 1.4 times orbital velocity, so it's going to take let's see-- 7500 m/s * 1.4 - 7500, wow only about 2 years! Of course this is just the acceleration of the sail, if the satellite package has any mass, you're going to have to add more sail to help drag that along.
Did a little back of the spreadsheet calculation. If you take thr trhrust numbers fomr the article, you get a kilogram of thrust from every square kilometer. That's a millionth of a Kg from every square meter. Or a thousandth of a gram. If you assume the sail weighs .1 gram per square meter, that's an acceleration of 1/100th of a G. Not terribly impressive. Certainly not enough to push anything out of earth orbit. And a very slow way to tour the solar system. And what do you do at night? :)
Sorry to be such a Grumpy Gus about this. I have plenty of respect for the people and projects. tht's not the issue. The issue in my mind is that history has shown that human nature has a strong tendency to ignore, deflect, and even mislead when it comes to investigating mistakes and misdeeds. In soooo many cases, the real extent of the problems have been minimized and downplayed, often by huge factors. Just one example from this subject-- the Oak Ridge Boys would take water samples from the creek, and measure the mercury concentation with various extremely inadequate devices and processes. Everything measured jsut fine! Then a local yokel happened to mention "Ahem, but you can SEE actual droplets of mercury on the creek bottom!" "Ohhhhh, we're not instructed to take BOTTOM samples!". The tendency in any big organization is of course, to keep the organization going at all costs. So there's every effort made to not see the problems, to fund studies that will look in the wrong places, to classify studies as "national security" that look bad, to mandate reforms that are never funded, to implement token cleanups, you all know the drill. For example, as to actual cleanups, googling shows very little going on. Some mercury was removed from a sump. A big story in the paper about "cleanup finished", if you read the fine print, reveals that only 1/100th of the estimated $ amount was funded, and eventually only 13 acres had some lacadaisical scraping. And the scraped dirt wasnt cleaned! It was just moved to another site. Now maybe a HUGE cleanup was done, but funny that Google doesnt catch it, and the DOE didnt publicize it. It's nothing personal, but I just hate to see all the BS the still surrounds issues like these. Regards, A_H
More BS! Please explain how they're cleaning up the mercury in the soil and water and sediments. AFAIK there's no way to do so. Do they have the whole creek roped off? The one estimate I've seen says 500 lbs per year are washing off into the creek. That's still an awful lot. Seeing as there are advisories many places about eating lake fish that have excessive mercury form power plant emissions, what are the advisories about fishing in the Oak ridge area? What are the mercury levels in the fish? 776K tons of mercury is a whole lot. BTW the foolish things with mercury were in the 1950's, not during WWII, so the hot-war excuse is not applicable.
Oh yes, Japan and France, go to it! Never mind the laws of Physics! All those equations with squares, cubes and quad powers in them-- ignore them. All the experience with the Concorde, The Blackbird, the Valkrie, the B-58-- just ignore how expensive it is to build and maintain an airplane made out of Titanium. Also ignore how much fuel it takes to push a big plane through the air at that speed, with the air resistance going up as the fourth power of the speed. And how you're carrying most of the fuel halfway around the world, at air-mail rates. And doing so over an Artic route, with not a chance at a safe landing or a prompt rescue. That's JUST what the US air industry needs, having you go off on some hopeless quest.
- This may bell be just a PR campaign to make the place look better. Lots of things you won't hear on the tour:
- The calutrons were basically a FAILURE-- they only put out about 10% of the expected U235-- the rest they smeared all over the place, and not in the collection bucket. Once the gas diffusion plant got running the calutrons were relegated to secondary status. Being extremely expensive and inefficient to boot, they were shut down ASAP after the war.
- They were built mostly due to Lawrence's reputation in building the cyclotron, not on any technical merit.
- Ask about when the building had most of the world's mercury flowing through its pipes. And how much got lost. A DOE report says: "A 1983 study by USDOE estimates that 733,000 pounds of elemental mercury were released to the environment in the 1950s and 1960s around the Y-12 Plant. Most of the contamination around Y-12 is confined to the upper 10 feet of soils and fill. Additional studies revealed that some 170,000 pounds of mercury are contained in the sediments and floodplain of about a 15-mile length of East Fork Poplar Creek (EFPC), which has its headwaters at Y-12, and that some 500 pounds of mercury annually leave this watershed." ( i.e.: don't smoke the grass)
- Ask about the nearby sites where they dumped tons of radioactive waste right into the creeks and hollers.
Just MHO but his would be one of the LAST places on Earth I'd care to visit.A scroll wheel is really cheap, it's just like the roll sensors, only turned upwards. Maybe 50 cents added cost. A scroll panel is a much more comlex device, with a capacitive or resistive transducer, x-y driving and sensing electronics, and a/d converters. Several $ I'd guess. By the time these costs go up the manufactiring and distribution and retail paths, we're up to many $ difference. It's hard to see paying that much more for a solution to a non-problem.
I wonder how they'll transparently handle all the endian issues? Every data file with binary integers in it will have to be converted. Arghhh!
Energy savings, WHAT energy savings? Charging a battery is not 100% efficient, discharging it even less so. The only saving comes from the supossedly smaller and lighter gas engine.
A 8 year guaratee isnt that great, if it's your typical pro-rated battery warranty. After 4 years you're down to half the original warranty, dropping down to zero after 8 years.
AFAIK the hybrid car makers don't have any special NiMH magic batteries. All rechargeable batteries lose a little capacity on each and every charge/discharge cycle. The best NiMH's seem to be good for 500 to 1000 full cycles. Now maybe hybrid vehicles get more cycles if they don't discharge the cells too deeply. But eventually the cells *will* need replacing, and the piper must be paid. And the cost isnt peanuts either. If we assume the cost will come down to $10K, that's still another 10 cents a mile of hidden cost.
Methinks this is more of the traditional brainwashing to get Japanese to buy more and newer things to stimulate a sagging economy.
And there's not much use for a switch that small-- individual molecules arent and cant be made reliable enough. just your basic room temperature heat is enough to disrupt these things due to normal diffusion. Just one weak cosmic ray and the whole thing is toast.
think of it more as a geeky parlor trick, nothing more.
A triple load:
Richard Feynman has been over this ground. He once read some medical article that concluded that iron was responsible for fevers. You see he took his sick wife's temperature, plotted the fever curve, then looked in a chemistry book for a reaction that matched that curve. Some iron reaction matched the best, therefore he triumphantly concluded that iron caused fevers.
Same thing, different decade. We have gotten not a whit wiser in fifty years.
Well, not to get into a flame war, but I just did a Google search on "the sprit is willing". The actual phrase it turns out is "the spirit is indeed willing". Which showcases the other downfall of phrase-matching-- just one inserted word that doesnt change the meaning or horribly inverts the meaning will trip up any dumb phrase matcher. For example, the google matcher is more likely to glom onto the soap opera "The spirit is willing", rather than the exact biblical verse "the spirit is indeed willing". Or if the extra word is somehing negatory, or sarcastic, like "the spirit is NOT willing", or "The spirit is like bodaciously willing". It's unlikely that every possible permutation with 1,2,3,4 added adjectives or adverbs is going to be found in text somewhere, so there are going to be a lot of non-matches or mismatches. JMHO.
"The spirit is willing, but the flesh is weak"
The computer crunched and crunched, tapes spun (this was back in the 60's) and eventually it printed out:
"The wine is pretty good, but the steak is lousy"
Therein encapsulated is all the folly of every attempt at word-matching translation.
The other factoid is the 2Km-long test pipe cost $11M. Generously assuming there's 100 MW of heat going thru the pipe, at 2% efficiency thats 2 megawatts of electricity, which is only about $50/hr's worth, or $450,000 per year. Assume you need 5 employees at $50K/yr, that eats up 250K of your profit. It's hard to pay off a $11M loan when your income is less than one tenth the interest cost.
Yep, go look. Not a single number that I could find. In their Q & A section, they pose the question "What's the efficiency?" then they babble and never answer the question. Hmmmm....