The fuel has higher specific impulse than kerosene and oxygen, but until now has been thought to have too much 'technology risk'
There hasn't been much use, because rocket design has been on a different track than XCOR. Kerosine engines are primarily used for their high thrust to weight ratios, which help get a rocket off the ground. Once the rocket is in flight, the first stage is usually dropped in favor of a more powerful engine, such as Liquid Hydrogen/Oxygen engines. LHOx has the highest specific impulse of any fuel deployed to date; even more efficient than the methane-oxygen engines they're proposing.
The problem is that XCOR is working on a different track than NASA and the large rocket manufacturers. They're focusing on winged takeoff and landing, where high thrust to weight ratios aren't as important, and can be sacrificed for greater efficiency. (For comparison, the kerosine F-1 engines on the Saturn V produced 1.5 million lbf compared to the 7,500 lbf targetted by this engine.) So the methane-oxy engine development has less to do with politics, and more to do with the practical matters of meeting the targetted design goals.
i.e. picking one gate and 1 route may not allow certain gates to be connected... so the 6 to 1 ratio refers to "wasted gates"... I believe.
I see what you mean. Generally, FPGA devs are always talking about reworking your design to eliminate as many wasted gates as possible. (The ISE tools help with this, IIRC.) Xilinx claims that their compilers are smart enough to rework your design automatically for a high rate of utilization.
Of course, proper utilization is partly a function of which FPGA you use. Most FPGAs have a lot of common circuits built in so that the general logic isn't wasted by those circuits. So doing an analysis of your design can help you pick the proper chip to get the necessary results. 6 to 1 is probably a bit pessimistic for a well-optimized design, but may hold true for a general design.
BTW, you may want to revise your example downward next time. 30 million gates is a LOT of gates. Very few devices offer that level of configurability. Comparing 50,000 to 300,000 gates is a bit more reasonable.:)
For those of you who didn't quite follow greenrom's excellent (but rather technical) post, he's basically saying that doing a task in hardware is faster than doing it in software. What FPGAs allow you to do is to create nearly any form of hardware device just by uploading a new design. While you can use this ability to create a new CPU, it's likely to be much slower than a regular CPU. Thus FPGAs are more useful for hardware like network routers, graphics chip research, codecs, and other highly specialized hardware designs.
In fact, a common FPGA design is to have a regular CPU built into the FPGA chip which can then interface with whatever hardware you upload to the reconfigurable portion of the chip. This combination makes for the ultimate microcontroller as you get the performance of an ASIC CPU (a non-reconfigurable silicon chip) combined with the flexibility of a fully reconfigurable FPGA.
For example, here's a PowerPC chip with reconfigurable capabilities:
Again, the market for these chips is very specialized, but the potential uses are pratically limitless. You can basically implement any form of coprocessor you can possibily imagine, as long as it fits inside the available FPGA space.
The largest FPGA I have been taught about (and gotten to use) had 22,000 transistors on it, I thought your average CPU was supposed to have billions.
You are seriously behind the times, my friend. Xilinx's smallest offerings provide ~20,000 gates, while their largest offerings offer millions of gates placed on a chip of over 1.1 billion transistors.
22K transistors is solidly inside CPLD territory these days.:)
granted on most of them you have to know verilog or vhdl to use them
JHDL is my favorite alternative to these languages. Rather than embedding the behavior in the language itself (which I personally think is the source of most confusion and poor HDL design) JHDL provides you with Java APIs that can be used to construct the circuit.
It works surprisingly well, in part because circuit design is more object oriented to begin with. Just like in good OOP design, you want your circuits to be simple, black-box designs that will always produce output Y for input X. More complex circuits can be designed by simply "snapping together" smaller circuit Objects to create larger, more complex entities.
As a rule of thumb i was told... an fpga normally uses 6 gates to 1 gate used by a custom ASIC chip... so a 5 million gate chip would require a FPGA with 30 million gates...
Pardon me if I'm speaking out of turn, but don't you mean transistors, not gates? In theory, the gate count should remain the same between the two, with most differences being accounted for by designing gates out of different gates. (e.g. Using NAND to create all other gates.) Or are you referring to a formula for translating the FPGA market-speak into real numbers?
Again, pardon me if I'm misunderstanding. I don't work with these chips nearly as much as I'd like to.
The RPU is a fully programmable ray tracing hardware architecture, with support for programmable material, geometry and lighting. The RPU combines the efficiency of GPUs with the advantages of ray tracing. The instruction set of the RPU is GPU like, which is optimal for shading purposes. In addition the RPU supports fast ray traversal through an k-D tree using a dedicated hardware unit and recursive function calls, usefull for recursive ray tracing. To increase efficiency always 4 rays are handled in a packet and multi-threading allows for high utilization of the hardware units.
A working prototype of this hardware architecture has been developed based on FPGA technology. The ray tracing performance of the FPGA prototype running at 66 MHz is comparable to the OpenRT ray tracing performance of a Pentium 4 clocked at 2.6 GHz, despite the available memory bandwith to our RPU prototype is only about 350 MB/s. These numbers show the efficiency of the design, and one might estimate the performance degrees reachable with todays high end ASIC technology. High end graphics cards from NVIDIA provide 23 times more programmable floating point performance and 100 times more memory bandwidth as our prototype. The prototype can be parallelized to several FPGAs, each holding a copy of the scene. A setup with two FPGAs delivering twice the performance of a single FPGA is running in our lab. Scalability to up to 4 FPGA has been tested.
BTW, am I the only one who thinks it darn cool that the SaarCor team does their work in JHDL rather than VHDL or (ugh) Verilog? I wonder if the RPU is also JHDL?
In layman's terms, FUSE is an operating system driver that allows you to use a regular application as a file system driver. i.e. Instead of installing a special kernel module or DLL file, you simply run an application. Since you can pass parameters to that application, it becomes ideal for tasks like mounting ZIP files or SMB shares. Basically, stuff that's very transient and could otherwise crash your system. In the case of FUSE, your system is protected against a crash in the same way it's protected against any application crash.
This is totally, utterly useless, in a practical sense.
Are you kidding me?!? I'm going to use that as my new encryption key! It will be like UBER-secure and take ten hundred billion, billion YEARS to guess!
So close. It would have been perfect if you'd written it as, "Hi. I'm Larry from L.D.&D. Telecom, and this is my brother Daryl and my other brother Daryl.":P
Just an FYI, your local Gamestop may have the stupidest reason for people playing only the PS3. At the Gamestop I went to, everyone was playing the XBox 360. However, it wasn't because the system was so popular. It was because the PS3 was turned off and the Wiimote batteries were dead.
With Verizon aggressively rolling out high-speed FiOS (FTTP) in its service area, what will happen to the consumers stuck with a smaller telco like those moving to FairPoint?"
They get better service?
Big telcos like Verizon tend to focus on large population areas first, because that's where the money is. Which means that the major cities get more options and better service while Bob Newhart over in Middlebury, Vermont can forget about ever getting Fiber service. In fact, I'd guess that the sale of the rural lines in these areas are being done specifically so that Verizon doesn't have to deploy FiOS as promised.
In comparison, a small company like Fairpoint is going to have to focus on the customers they've got. Which means either making them happy, or losing the business to local Co-Ops setup to provide the missing services.
Online stores can't keep PS3s in stock for more than a hour at a time as restock shows up. You got that you miserable fucking troll?
I see that you're afflicted with a metal disorder. No worries, mate, we believe in healing around these parts! Can I hear an AMEN out there?
<Faith-Service-Pastor> There ain't nothin' that God can't heal, my poor man! Hallelujah! Let's all pray for this poor fellow, bring the heeeeaaaling of Jesus on his poor soul! I can feel it working now, my friend. Oh yes, Lord Jesus. Hallelujah! We'll make you right as rain, my friend.
'Cause this train is bound for glory, this train. This train is bound for glory, this train! This is bound for GLOR-A Don't ride nothing but the holy. This train is bound for glory, this train!
Can ya' feel the Holy Spirit moving my boy? Can you FEEL it??! Let's get up and DANCE boy! DANCE! Whoo! </Faith-Service-Pastor>
Nothing like a traditional Penecostal service to get the blood pumping and the healing, goin', eh? Feel better now?:P
They're still far deeper than Nintendos. Even if they don't have the cash reserves, they have sufficient credit to do nearly anything they need to do.
Personally, I hope the entire executive staff (also known as "pond scum") are evicted from their positions and replaced by a newer, more consumer-friendly bunch, but I don't think that's going to happen. At least not for a while. Which means that Sony will continue with their age old strategy of attempting to steamroll the competition.
If you don't have an Atari 2600 and/or don't want to track down a physical cart, it's not hard to find the ROMs on the 'net. You can use this little proggie for emulation:
Just remember to read the manual in my first link before playing! The 2600 was fun at times, but it was nowhere near as userfriendly as modern systems. Things that we take for granted today (e.g. title menus, controller buttons to start games, graphical option selection, etc.) were all invented after the 2600 was nearly dead and buried. (Or was that undead and outliving CD-ROM consoles?)
I sincerely doubt that. I was just in Gamestop on Sunday (a non-shipment day) asking if they knew when they'd get more Wiis. They didn't know, but they had PS3s if I wanted one.
I've heard dozens of similar reports from other shoppers, including massive stocks of PS3s in Austin, TX stores. (Apparently, the stores were trying to sell their PS3s as bundles, but eventually had to unbundle them to start unloading the units. This left them with a rather sizable overstock.) So you might as well accept the reality, the PS3 isn't selling all that well at the moment.
That being said, the release of Final Fantasy and White Knight will start driving more sales sometime in the not-to-distant-future. So you don't have to given up hope quite yet. Wait until next Christmas to see if Sony lowers the price. If they don't, well... it will not be a good day for Sony fans.:-/
If some really cool games don't ship this year the PS3 could just end up as another expensive game system nobody could justify buying.
To a certain degree, the same is true of the Wii. We're halfway through January now, and the majority of games on the horizon are Virtual Console games. That means that the hefty Gamecube library (of games most Wii owners haven't played) is holding up the value of the console. If the demand for the console wasn't keeping morale so high, you'd already be hearing grumbling about when new games will be coming out. The $250 price tag certainly wouldn't be convincing consumers to buy it just to play Gamecube games.
The only difference is that Nintendo managed their launch a lot better with greater supply, lower price tag, and a wider variety of cool games. Sony is scrambling only because they mis-managed their launch with a poor game selection, high price tag, and low availability. Things will get interesting next Christmas when both consoles have well-stocked libraries and lower price tags. Don't think for a minute that Sony isn't going to flex its market muscle and deep pockets at that time.
That being said, I think of lot of the PS3's eventual muscle will be deflected or absorbed by the XBox 360. Which would leave the Wii in a much better position. My only message to Nintendo is this: Don't get cocky!
If he takes his nebulous EJB spec with him, I'm all for it. Sun really should have cleaned that thing up before releasing it to the world. It's great in theory, but in practice almost no one implements the damn standard correctly! (Or at least, in a useful fashion.)
Wouldn't want to be wearing one in the desert (jungle, etc), probably a reason why there is limited government interest. Unless this things has some sort of personal AC unit... but that would probably require portable energy beyound military logistical capabilies.
In this video, he claims that the built-in AC unit is powered by powerpacks on the back of the helmet with solar recharging capability. (I presume the headlights are powered by the same packs.) FWIW, there are battery packs with extremely long field-use durability. Nothing incredible, but enough to keep the guy suited for an 8 hour mission before he has to visit the charger to swap battery packs.
Getting back to the Yucca Mountain thread the other day, they *could* use some of that material for batteries that never die, or at least recharge themselves. Unfortunately, I doubt the military would want to take the chance of any radioisotopes getting into the hands of enemy combatants.
I wish. I keep asking at every store I visit, but nothing. Just yesterday I was at Gamestop and they tried to sell me a PS3 instead. They sounded almost desparate to unload the things. (Though I don't understand why???)
This clearly does not allow for loans to a private person in any reasonable economy.
Muslim banks have an interesting way of getting around this. The bank pays to build the house, and thus owns the home. While you are making payments toward ownership, you pay rent to live in the home. In this way, Muslim banks effectively charge interest without charging interest.
Personally, I think they should call a duck a duck, but I suppose their arrangement has some interesting legal ramifications.
i like your posts and all, but for heaven's sake, socialism is not communism is not the crap that people sold as a people's revolution.
Never said it was. If you'll turn your attention to the last line of my post, I think you'll find that I pointed you to the modern form of socialism I was referring to.
Socialism hasn't had much to do with Marxism since... oh... most of my life.:)
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There hasn't been much use, because rocket design has been on a different track than XCOR. Kerosine engines are primarily used for their high thrust to weight ratios, which help get a rocket off the ground. Once the rocket is in flight, the first stage is usually dropped in favor of a more powerful engine, such as Liquid Hydrogen/Oxygen engines. LHOx has the highest specific impulse of any fuel deployed to date; even more efficient than the methane-oxygen engines they're proposing.
The problem is that XCOR is working on a different track than NASA and the large rocket manufacturers. They're focusing on winged takeoff and landing, where high thrust to weight ratios aren't as important, and can be sacrificed for greater efficiency. (For comparison, the kerosine F-1 engines on the Saturn V produced 1.5 million lbf compared to the 7,500 lbf targetted by this engine.) So the methane-oxy engine development has less to do with politics, and more to do with the practical matters of meeting the targetted design goals.
Here's another story on it with a slideshow:
t heater/
http://www.electronichouse.com/article/star_trek_
I see what you mean. Generally, FPGA devs are always talking about reworking your design to eliminate as many wasted gates as possible. (The ISE tools help with this, IIRC.) Xilinx claims that their compilers are smart enough to rework your design automatically for a high rate of utilization.
Of course, proper utilization is partly a function of which FPGA you use. Most FPGAs have a lot of common circuits built in so that the general logic isn't wasted by those circuits. So doing an analysis of your design can help you pick the proper chip to get the necessary results. 6 to 1 is probably a bit pessimistic for a well-optimized design, but may hold true for a general design.
BTW, you may want to revise your example downward next time. 30 million gates is a LOT of gates. Very few devices offer that level of configurability. Comparing 50,000 to 300,000 gates is a bit more reasonable.
For those of you who didn't quite follow greenrom's excellent (but rather technical) post, he's basically saying that doing a task in hardware is faster than doing it in software. What FPGAs allow you to do is to create nearly any form of hardware device just by uploading a new design. While you can use this ability to create a new CPU, it's likely to be much slower than a regular CPU. Thus FPGAs are more useful for hardware like network routers, graphics chip research, codecs, and other highly specialized hardware designs.
f pgas/virtex/virtex4/capabilities/powerpc.htm
In fact, a common FPGA design is to have a regular CPU built into the FPGA chip which can then interface with whatever hardware you upload to the reconfigurable portion of the chip. This combination makes for the ultimate microcontroller as you get the performance of an ASIC CPU (a non-reconfigurable silicon chip) combined with the flexibility of a fully reconfigurable FPGA.
For example, here's a PowerPC chip with reconfigurable capabilities:
http://www.xilinx.com/products/silicon_solutions/
Again, the market for these chips is very specialized, but the potential uses are pratically limitless. You can basically implement any form of coprocessor you can possibily imagine, as long as it fits inside the available FPGA space.
You are seriously behind the times, my friend. Xilinx's smallest offerings provide ~20,000 gates, while their largest offerings offer millions of gates placed on a chip of over 1.1 billion transistors.
22K transistors is solidly inside CPLD territory these days.
JHDL is my favorite alternative to these languages. Rather than embedding the behavior in the language itself (which I personally think is the source of most confusion and poor HDL design) JHDL provides you with Java APIs that can be used to construct the circuit.
It works surprisingly well, in part because circuit design is more object oriented to begin with. Just like in good OOP design, you want your circuits to be simple, black-box designs that will always produce output Y for input X. More complex circuits can be designed by simply "snapping together" smaller circuit Objects to create larger, more complex entities.
Pardon me if I'm speaking out of turn, but don't you mean transistors, not gates? In theory, the gate count should remain the same between the two, with most differences being accounted for by designing gates out of different gates. (e.g. Using NAND to create all other gates.) Or are you referring to a formula for translating the FPGA market-speak into real numbers?
Again, pardon me if I'm misunderstanding. I don't work with these chips nearly as much as I'd like to.
Yes, actually. BTW, am I the only one who thinks it darn cool that the SaarCor team does their work in JHDL rather than VHDL or (ugh) Verilog? I wonder if the RPU is also JHDL?
In layman's terms, FUSE is an operating system driver that allows you to use a regular application as a file system driver. i.e. Instead of installing a special kernel module or DLL file, you simply run an application. Since you can pass parameters to that application, it becomes ideal for tasks like mounting ZIP files or SMB shares. Basically, stuff that's very transient and could otherwise crash your system. In the case of FUSE, your system is protected against a crash in the same way it's protected against any application crash.
Are you kidding me?!? I'm going to use that as my new encryption key! It will be like UBER-secure and take ten hundred billion, billion YEARS to guess!
[...]
Um... I wasn't supposed to tell you that, was I?
If you've got DSL, then you're probably not "rural". I wouldn't worry about it.
So close. It would have been perfect if you'd written it as, "Hi. I'm Larry from L.D.&D. Telecom, and this is my brother Daryl and my other brother Daryl."
Just an FYI, your local Gamestop may have the stupidest reason for people playing only the PS3. At the Gamestop I went to, everyone was playing the XBox 360. However, it wasn't because the system was so popular. It was because the PS3 was turned off and the Wiimote batteries were dead.
As I said, the stupidest reasons.
They get better service?
Big telcos like Verizon tend to focus on large population areas first, because that's where the money is. Which means that the major cities get more options and better service while Bob Newhart over in Middlebury, Vermont can forget about ever getting Fiber service. In fact, I'd guess that the sale of the rural lines in these areas are being done specifically so that Verizon doesn't have to deploy FiOS as promised.
In comparison, a small company like Fairpoint is going to have to focus on the customers they've got. Which means either making them happy, or losing the business to local Co-Ops setup to provide the missing services.
...for nothing more than the cost of a Cease & Desist.
Nice. (For Apple, that is.)
I see that you're afflicted with a metal disorder. No worries, mate, we believe in healing around these parts! Can I hear an AMEN out there?
<Faith-Service-Pastor>
There ain't nothin' that God can't heal, my poor man! Hallelujah! Let's all pray for this poor fellow, bring the heeeeaaaling of Jesus on his poor soul! I can feel it working now, my friend. Oh yes, Lord Jesus. Hallelujah! We'll make you right as rain, my friend. Can ya' feel the Holy Spirit moving my boy? Can you FEEL it??! Let's get up and DANCE boy! DANCE! Whoo!
</Faith-Service-Pastor>
Nothing like a traditional Penecostal service to get the blood pumping and the healing, goin', eh? Feel better now?
They're still far deeper than Nintendos. Even if they don't have the cash reserves, they have sufficient credit to do nearly anything they need to do.
Personally, I hope the entire executive staff (also known as "pond scum") are evicted from their positions and replaced by a newer, more consumer-friendly bunch, but I don't think that's going to happen. At least not for a while. Which means that Sony will continue with their age old strategy of attempting to steamroll the competition.
Dang, beat me to it. There goes my "what do you mean it's on hold?" gag.
As a consolation prize, here's a link to information on the game (for those who don't know):
http://www.atariage.com/software_page.html?Softwa
If you don't have an Atari 2600 and/or don't want to track down a physical cart, it's not hard to find the ROMs on the 'net. You can use this little proggie for emulation:
http://stella.sourceforge.net/
Just remember to read the manual in my first link before playing! The 2600 was fun at times, but it was nowhere near as userfriendly as modern systems. Things that we take for granted today (e.g. title menus, controller buttons to start games, graphical option selection, etc.) were all invented after the 2600 was nearly dead and buried. (Or was that undead and outliving CD-ROM consoles?)
I sincerely doubt that. I was just in Gamestop on Sunday (a non-shipment day) asking if they knew when they'd get more Wiis. They didn't know, but they had PS3s if I wanted one.
I've heard dozens of similar reports from other shoppers, including massive stocks of PS3s in Austin, TX stores. (Apparently, the stores were trying to sell their PS3s as bundles, but eventually had to unbundle them to start unloading the units. This left them with a rather sizable overstock.) So you might as well accept the reality, the PS3 isn't selling all that well at the moment.
That being said, the release of Final Fantasy and White Knight will start driving more sales sometime in the not-to-distant-future. So you don't have to given up hope quite yet. Wait until next Christmas to see if Sony lowers the price. If they don't, well... it will not be a good day for Sony fans.
To a certain degree, the same is true of the Wii. We're halfway through January now, and the majority of games on the horizon are Virtual Console games. That means that the hefty Gamecube library (of games most Wii owners haven't played) is holding up the value of the console. If the demand for the console wasn't keeping morale so high, you'd already be hearing grumbling about when new games will be coming out. The $250 price tag certainly wouldn't be convincing consumers to buy it just to play Gamecube games.
The only difference is that Nintendo managed their launch a lot better with greater supply, lower price tag, and a wider variety of cool games. Sony is scrambling only because they mis-managed their launch with a poor game selection, high price tag, and low availability. Things will get interesting next Christmas when both consoles have well-stocked libraries and lower price tags. Don't think for a minute that Sony isn't going to flex its market muscle and deep pockets at that time.
That being said, I think of lot of the PS3's eventual muscle will be deflected or absorbed by the XBox 360. Which would leave the Wii in a much better position. My only message to Nintendo is this: Don't get cocky!
If he takes his nebulous EJB spec with him, I'm all for it. Sun really should have cleaned that thing up before releasing it to the world. It's great in theory, but in practice almost no one implements the damn standard correctly! (Or at least, in a useful fashion.)
In this video, he claims that the built-in AC unit is powered by powerpacks on the back of the helmet with solar recharging capability. (I presume the headlights are powered by the same packs.) FWIW, there are battery packs with extremely long field-use durability. Nothing incredible, but enough to keep the guy suited for an 8 hour mission before he has to visit the charger to swap battery packs.
Getting back to the Yucca Mountain thread the other day, they *could* use some of that material for batteries that never die, or at least recharge themselves. Unfortunately, I doubt the military would want to take the chance of any radioisotopes getting into the hands of enemy combatants.
I wish. I keep asking at every store I visit, but nothing. Just yesterday I was at Gamestop and they tried to sell me a PS3 instead. They sounded almost desparate to unload the things. (Though I don't understand why???)
Muslim banks have an interesting way of getting around this. The bank pays to build the house, and thus owns the home. While you are making payments toward ownership, you pay rent to live in the home. In this way, Muslim banks effectively charge interest without charging interest.
Personally, I think they should call a duck a duck, but I suppose their arrangement has some interesting legal ramifications.
Never said it was. If you'll turn your attention to the last line of my post, I think you'll find that I pointed you to the modern form of socialism I was referring to.
Socialism hasn't had much to do with Marxism since... oh... most of my life.