Even if it's a very directional antenna, the bad guy on the ground can throw 10's of KW of RF at your receiver from 'closer' with the way less path-loss relative to your satellite. I was thinking of using satellite's too but there's no reason to assume the bad guys can't orbit one with jammers on-board too. If you say 'shoot them down' using SDI or something similar, then they could use the same to shoot down your satellites and you are back at square one.
Besides there are cheaper things than satellites too, like nothings stopping them from inflating a humungous weather baloon with a few big batteries and a powerful transmitter. The path loss from say 100000 ft is going to be way less than that for your satellite.
Antiphase? Have a receiver transmitter pair that receives the interference and then transmits the 180 degree out of phase equivalent - hopefully cancelling it out. For extra points deploy multiple stations, and for a bonus credit, don't evern transmit your signal, just modulate your antiphase to leave your signal as a remanant.
Physics Problems: Can you near instaneously send the anti phase (those radio waves travel quite quickly)...
What happens for moving receivers.....
Thinking that maybe other humanoids had a prior civilization, and we aren't unique is hardly anti-science. It's accepting the idea that if someone with essentially similar brain capacity and physical abilities may be able to climb the tool use ladder. I will grant you that it's like a conspiracy theory, but so was the theory that the earth orbited the sun a few hundred yeas ago.
The age that humans essentially similar to ourselves walked this planet is constantly pushed back. We now discover tool use nearly a million years earlier than previously thought. Yet for some it takes real temerity to suggest that possibly significant civilizations may have existed earlier in history. The best places to look would actually be in high orbit, the Moon or the Lagrange points between the Sun and Earth. The Moon is particularly good, due to lack of weather (We saw how the dust storms affected the Mars rovers!)
If we were all (99%) killed by a viral epidemic next year and civilization fell, it would be extremely hard to find significant traces of us just 30K years later. I still think that survivors, even if they fell back to 'bash things with stones' tool use might re-achieve our level of civilization. Likewise, since I'll give future humans that chance, I'd entertain that maybe we aren't the first who had a significant globe-spanning civilization and something went wrong.
Either of these possibilities really makes the argument that Hawking has been espousing much stronger. If we aren't the only civilization then we are rare. If we aren't then civilizations must rise and fall fairly frequently. Either way we need to get humanity established elsewhere, and someone should be thinking hard about what to send back to earth/leave here to help the lower level of civilization re-climb the ladder.
The handicapper general peered odiously over her spectacles at the latest product roadmap, her mood growing ever more dark at the clearly typed columns and performance ratios for common tests of the new devices.
Why couldn't those damn engineers be more like marketing she thought, comparing the crumpled smudged, poorly written marketting copy to the neat engineering report. Why, even when the marketing copy was well typed, spelled and readable it still made no real sense.
The engineers she realized had tricked her. "Bunny-Marks",what she had initially believed had been the wholehearted attempt by those engineers were a scam! She should have realized sooner regardless of the terms ' Number-of-paws', fur-fuzz' , 'ear size' and 'carrot factor' were clearly false names for real things. Even through her permanently oil smudged glasses she could see that there was a clear progression from slow bunnies to faster bunnies and this wouldn't do.
Slowly, a smile slipped across her face as she realized now she would have the justification to depressurize the scientists lab another 3000 feet. Let's see how those engineers did at 14000 ft! Oh she would make all the bunnies equal, or her initials weren't DMG.
As a Kiwi (living in the States) this law sounds absurd and redundant.
If you crash your car into another car then you clearly broke an existing law. If the police on investigation discover that you crashed it because you were reading a newspaper, reading a paper map, changing cassette tapes (ok that's an old example make it changing songs on MP3 player), rolling a cigarette or fiddling with your radio controls then they can charge you with careless driving or dangerous driving or some other thing - least of which would be failing to stop within the required distance.
So it's just a stupid duplicate law that takes the country towards 'nanny-nation' status but probably results in some politician saying 'I'm tough on road safety'.
Kiwis need to speak up and tell the politicians how stupid this is and looks to the rest of the world. Adding useless laws expends resources which if NZ really wants to be a 'greener' place this sure as hell won't help. Just think how many hours will be spent (expending resources for things like heat and lighting) as lawyers and politicians write this crap, print this crap and read this crap.
Rather than spending the time on real issues like funding an infrastructure that helps the country once they can't afford oil because of rampant inflation like in the late 70's / early 80's and it costs too much to drive the tankers way down there.
Star Raiders was a great game. It was fast, hard and a really fun game to play. Considering when it came out, it was a real testament to just how good the Atari 8 bit was in terms of graphics and sound. It was all there - display list with different modes, player-missile graphics (sprites), good sound effects for the time, and fast 3D action. In general the Atari 8 Bits excelled at real-time 3D types of games compared to the C-64 (Encounter anyone?). The 64 kicked the 800's butt in terms of platform games (it has better sprites) and everyone loved SID. Paradroid was great, and who can forget the Last Ninja tunes, ghosts and goblins etc. To get a good idea of what the 8 bit was capable of check out 'De Re Atari'... it's by the guy who wrote Star Raiders. it's a really good read, and any Amiga hackers will see lots of deja-vu when they read how players work and priority levels and the magic that was Jay Miner.
http://www.atariarchives.org/dere/
No flame war intended here. Like I said the C-64 was an awesome machine in it's own right and rocked.
Here's how I think of the lineage (regardless of company)
Atari 8 bit -> Amiga
C64 -> Atari ST (but not so good a fit, maybe the Atari ST is more like a new PET?).
Any commodore history folks have some insight? The C-64 for the time was better than the ST in my opinion. Jay Miner actually wanted to build a 68K based successor to the 8 bit at Atari and when management said no he left and did it anyway and we got the Amiga.
You do realize that the SSC was built and completed right? Back in the 90's it ran at full power and tore us off our original world-line. After bouncing through a number of 'energy levels' we eventually fell down to this lowest ground state world-line where the Higgs had a sufficient energy level to not cause interactions that made things seem very weird to anyone used to either the original or this current world-line. In this world-line the SSC had been canceled during construction, leaving an impressive hole in the ground full of plastic parts. It's all going to happen again - Pink will be Blue, Democrats will be Republicans, Light switches will be on when down, and off when up causing me to shock the crap out of myself again.
There should be a standard posted for such a meter, and the consumer should have a choice of different places to get it from, and a list of qualified people to install it.
The power company can then come and inspect the installation - but there shouldn't be anything other than the equvalent of the one-time cost a consumer has when they upgrade the service to their old house from 75 amp to 200 amp service.
I'm wondering what happens if they have a net of too many generators versus consumers. Ie more power generated than is demanded.
It's TANSTAAFL basically. There's a cost to the power company for providing connectivity to a solar users house. It costs them money to run the power lines, and to have the workforce that can service those lines. It costs them money to have capacity available for that Solar user on a cloudy day.
If users generate more power than they use and feed power back intot he grid - then the power company should pay for it. If they do pay for it - it should defray the cost for that connection.
A fair system would be an itemized bill that covers all the components of the system. Distribution and line-upkeep are real costs. Just because someone sticks a pile of Solar in their backyard / roof / ranch doesn't mean that magically the power lines running to the house become free.
Prolog & Assembler. Then the functional languages suggested by many other posts.
Teach them declarative problem solving first. Followed up with 'how processors work '(Assembler). Describe a hypothetical Prolog interpreter with a focus on the trees (this gives them pointers). Logo will start them thinking functionally - which is a nice transition from logic programming.
With an Assembly background pointers will be easy to understand if they need to grasp C, and linked-lists of pointers will be clear based upon prior exposure to the 'Prolog trees'. With a declarative background they won't be stuck in imperative lock-step. With the functional stuff they can get into some of the interesting Math. For fun throw in there dataflow so they are thinking in terms of Legion.
If they are *very* gifted - toss them Backus Turing Award Lecture about FP. After all that, give em Perl for 'integration crazy glue'.
They'd be fine until their favorite assembler optimized the FAR JMP into a SHORT JMP, and on engagement of hyperdrive the CPU bounced too close to a super nova because the TLB's hadn't been flushed...
1) A 4 bit superhigh (say 20 Ghz) processor. Great for flipping bits on and off, if you can make it 8 bits, great, but I'd take 4. That lets me do a 16 way branch, and my brain works best with 7 values, so 16 would be plenty.
2) A really super wide VLIW or dataflow processor that runs much slower, but has more functional units that you can shake a stick at. I want this to run at a synchronous speed with the very wide memory it is interfaced to. I don't really want a cache, I want my memory really wide.
Exactly! C when designed showed a close match to the underlying architecture of common machines. Contrast this with a modern microprocessor - RISC - Really Post RISC now, or CISC. Consider the underlying microarchitecture of an OOO 4 way superscalar MPU. What would a programming language look like if we took away the ever futher from the metal ISA and wrote much closer to the metal? Itanium perhaps?
How many physical registers in a Core duo / Athlon 64, what does the cache behave like, what groups of instructions can execute simultaneously? Would C translate well to this model? Would you really want to treat arrays and pointers the same on a machine with memory protection? What considerations would you want to make about function calls, memory allocation, stack usage? What language details would you want to add to handle the prevalence of SIMD instructions?
If C compilers could write to the metal on modern CPUs what would performance be like? I wish the Nx586 had been more successful, and we had all gotten a chance to turn off that x86 translation layer...
I think half the problem is some programmers have never worked at the embedded level, or only early processors where an instruction could be shown to be a set sequence of logical events. The disparity between modern ISA's and what is going on at the low level is growing all the time.
I've seen it happen multiple times on my 2000 box. A 35 MB/sec drive drops down to about 4 MB/sec. It's worst when your DVD/CD drive is on the same controller. You throw in a bad disk and windows decides that flakey things are going on and reverts you back to PIO.
A real PITA - and a good reason for always putting optical drives on their own controller.
(1) What is the target application, does it have latency requirements? You may not want to use Java if it does - or program like your writing code for Javacard or J2ME (Create your objects at startup and don't just new yourself into GC hell).
(2) You probably want to think about the algorithm first. A 100x faster native CPU won't do much good if your algorithm is coded O(n!) vs O(n^2) on the interpreted platform.
(3) Bandwidth is money, latency is forever.
(4) It was once said that LISP / PROLOG were too memory hungry. Big Institutions could afford memories of say 4 MB and fast CPU's. Now you quite possibly have more than 5 VAX MIPS in your cellphone and more memory than that late 70's / early 80's VAX too.
Here's a final question. Suppose your requirement was to write the embedded code for a medical radiation therapy machine. The machine has to: 1) Turn on and off the beam. 2) Rotate the beam around some axis. Screwing up could mean fatality. What language / environment would you use then? Imagine your loved one has to lie on this thing.
Java with the GC possibly getting in the way? C? -- Pointer smashing? C++ -- Ditto... Lisp, Mercury, Erlang, Ada, Modula 2, Eiffel, Assembler? No software?, hardware? / a finite state machine?
Dude,
You've obviously never shorted out a NICAD cell before. The wire turns red hot and the insulation melts. The NICAD just says 'Is that all you've got? CoMe On! FeeL the BuRn BabY!'
--Tarp
Slashdot Mirror
Even if it's a very directional antenna, the bad guy on the ground can throw 10's of KW of RF at your receiver from 'closer' with the way less path-loss relative to your satellite. I was thinking of using satellite's too but there's no reason to assume the bad guys can't orbit one with jammers on-board too. If you say 'shoot them down' using SDI or something similar, then they could use the same to shoot down your satellites and you are back at square one. Besides there are cheaper things than satellites too, like nothings stopping them from inflating a humungous weather baloon with a few big batteries and a powerful transmitter. The path loss from say 100000 ft is going to be way less than that for your satellite.
Good luck modulating it unless you have a very electrically charged big-bang tiny black hole that you convinced not to evaporate.
Antiphase? Have a receiver transmitter pair that receives the interference and then transmits the 180 degree out of phase equivalent - hopefully cancelling it out. For extra points deploy multiple stations, and for a bonus credit, don't evern transmit your signal, just modulate your antiphase to leave your signal as a remanant. Physics Problems: Can you near instaneously send the anti phase (those radio waves travel quite quickly)... What happens for moving receivers.....
Thinking that maybe other humanoids had a prior civilization, and we aren't unique is hardly anti-science. It's accepting the idea that if someone with essentially similar brain capacity and physical abilities may be able to climb the tool use ladder. I will grant you that it's like a conspiracy theory, but so was the theory that the earth orbited the sun a few hundred yeas ago.
The age that humans essentially similar to ourselves walked this planet is constantly pushed back. We now discover tool use nearly a million years earlier than previously thought. Yet for some it takes real temerity to suggest that possibly significant civilizations may have existed earlier in history. The best places to look would actually be in high orbit, the Moon or the Lagrange points between the Sun and Earth. The Moon is particularly good, due to lack of weather (We saw how the dust storms affected the Mars rovers!) If we were all (99%) killed by a viral epidemic next year and civilization fell, it would be extremely hard to find significant traces of us just 30K years later. I still think that survivors, even if they fell back to 'bash things with stones' tool use might re-achieve our level of civilization. Likewise, since I'll give future humans that chance, I'd entertain that maybe we aren't the first who had a significant globe-spanning civilization and something went wrong. Either of these possibilities really makes the argument that Hawking has been espousing much stronger. If we aren't the only civilization then we are rare. If we aren't then civilizations must rise and fall fairly frequently. Either way we need to get humanity established elsewhere, and someone should be thinking hard about what to send back to earth /leave here to help the lower level of civilization re-climb the ladder.
Is this thing single use? Could we string 10 of these together and use it for laser launch vehicles out in the middle of the pacific?
The handicapper general peered odiously over her spectacles at the latest product roadmap, her mood growing ever more dark at the clearly typed columns and performance ratios for common tests of the new devices. Why couldn't those damn engineers be more like marketing she thought, comparing the crumpled smudged, poorly written marketting copy to the neat engineering report. Why, even when the marketing copy was well typed, spelled and readable it still made no real sense. The engineers she realized had tricked her. "Bunny-Marks",what she had initially believed had been the wholehearted attempt by those engineers were a scam! She should have realized sooner regardless of the terms ' Number-of-paws', fur-fuzz' , 'ear size' and 'carrot factor' were clearly false names for real things. Even through her permanently oil smudged glasses she could see that there was a clear progression from slow bunnies to faster bunnies and this wouldn't do. Slowly, a smile slipped across her face as she realized now she would have the justification to depressurize the scientists lab another 3000 feet. Let's see how those engineers did at 14000 ft! Oh she would make all the bunnies equal, or her initials weren't DMG.
As a Kiwi (living in the States) this law sounds absurd and redundant. If you crash your car into another car then you clearly broke an existing law. If the police on investigation discover that you crashed it because you were reading a newspaper, reading a paper map, changing cassette tapes (ok that's an old example make it changing songs on MP3 player), rolling a cigarette or fiddling with your radio controls then they can charge you with careless driving or dangerous driving or some other thing - least of which would be failing to stop within the required distance. So it's just a stupid duplicate law that takes the country towards 'nanny-nation' status but probably results in some politician saying 'I'm tough on road safety'. Kiwis need to speak up and tell the politicians how stupid this is and looks to the rest of the world. Adding useless laws expends resources which if NZ really wants to be a 'greener' place this sure as hell won't help. Just think how many hours will be spent (expending resources for things like heat and lighting) as lawyers and politicians write this crap, print this crap and read this crap. Rather than spending the time on real issues like funding an infrastructure that helps the country once they can't afford oil because of rampant inflation like in the late 70's / early 80's and it costs too much to drive the tankers way down there.
Star Raiders was a great game. It was fast, hard and a really fun game to play. Considering when it came out, it was a real testament to just how good the Atari 8 bit was in terms of graphics and sound. It was all there - display list with different modes, player-missile graphics (sprites), good sound effects for the time, and fast 3D action. In general the Atari 8 Bits excelled at real-time 3D types of games compared to the C-64 (Encounter anyone?). The 64 kicked the 800's butt in terms of platform games (it has better sprites) and everyone loved SID. Paradroid was great, and who can forget the Last Ninja tunes, ghosts and goblins etc. To get a good idea of what the 8 bit was capable of check out 'De Re Atari'... it's by the guy who wrote Star Raiders. it's a really good read, and any Amiga hackers will see lots of deja-vu when they read how players work and priority levels and the magic that was Jay Miner.
http://www.atariarchives.org/dere/
No flame war intended here. Like I said the C-64 was an awesome machine in it's own right and rocked.
Here's how I think of the lineage (regardless of company) Atari 8 bit -> Amiga C64 -> Atari ST (but not so good a fit, maybe the Atari ST is more like a new PET?).
Any commodore history folks have some insight? The C-64 for the time was better than the ST in my opinion. Jay Miner actually wanted to build a 68K based successor to the 8 bit at Atari and when management said no he left and did it anyway and we got the Amiga.
--Tarp
You do realize that the SSC was built and completed right? Back in the 90's it ran at full power and tore us off our original world-line. After bouncing through a number of 'energy levels' we eventually fell down to this lowest ground state world-line where the Higgs had a sufficient energy level to not cause interactions that made things seem very weird to anyone used to either the original or this current world-line. In this world-line the SSC had been canceled during construction, leaving an impressive hole in the ground full of plastic parts. It's all going to happen again - Pink will be Blue, Democrats will be Republicans, Light switches will be on when down, and off when up causing me to shock the crap out of myself again.
There should be a standard posted for such a meter, and the consumer should have a choice of different places to get it from, and a list of qualified people to install it.
The power company can then come and inspect the installation - but there shouldn't be anything other than the equvalent of the one-time cost a consumer has when they upgrade the service to their old house from 75 amp to 200 amp service.
I'm wondering what happens if they have a net of too many generators versus consumers. Ie more power generated than is demanded.
Hamsters Pfft!
You just need to tap some power from your ford nucleon in the garage.
It's TANSTAAFL basically. There's a cost to the power company for providing connectivity to a solar users house. It costs them money to run the power lines, and to have the workforce that can service those lines. It costs them money to have capacity available for that Solar user on a cloudy day.
If users generate more power than they use and feed power back intot he grid - then the power company should pay for it. If they do pay for it - it should defray the cost for that connection.
A fair system would be an itemized bill that covers all the components of the system. Distribution and line-upkeep are real costs. Just because someone sticks a pile of Solar in their backyard / roof / ranch doesn't mean that magically the power lines running to the house become free.
Mod the parent up
You could use your post as the marketing copy on a bottle/can of Paraquat.
Wonder why it took so long to figure it out - the article doesn't really say.
Dammit I knew posting on Slashdot on a Friday was a bad idea....
Thanks for the bugfix!
BzzZzzZz BrAiNzzzZzzzZ BzZzzz!
You know bees are useful for fertilizing plants and not just the sticky yellow stuff right?
I'd vote for
Prolog & Assembler. Then the functional languages suggested by many other posts.
Teach them declarative problem solving first. Followed up with 'how processors work '(Assembler). Describe a hypothetical Prolog interpreter with a focus on the trees (this gives them pointers). Logo will start them thinking functionally - which is a nice transition from logic programming.
With an Assembly background pointers will be easy to understand if they need to grasp C, and linked-lists of pointers will be clear based upon prior exposure to the 'Prolog trees'. With a declarative background they won't be stuck in imperative lock-step. With the functional stuff they can get into some of the interesting Math. For fun throw in there dataflow so they are thinking in terms of Legion.
If they are *very* gifted - toss them Backus Turing Award Lecture about FP. After all that, give em Perl for 'integration crazy glue'.
Stand back a safe distance and observe.
They'd be fine until their favorite assembler optimized the FAR JMP into a SHORT JMP, and on engagement of hyperdrive the CPU bounced too close to a super nova because the TLB's hadn't been flushed...
What I really want is the following:
1) A 4 bit superhigh (say 20 Ghz) processor. Great for flipping bits on and off, if you can make it 8 bits, great, but I'd take 4. That lets me do a 16 way branch, and my brain works best with 7 values, so 16 would be plenty.
2) A really super wide VLIW or dataflow processor that runs much slower, but has more functional units that you can shake a stick at. I want this to run at a synchronous speed with the very wide memory it is interfaced to. I don't really want a cache, I want my memory really wide.
Exactly! C when designed showed a close match to the underlying architecture of common machines. Contrast this with a modern microprocessor - RISC - Really Post RISC now, or CISC. Consider the underlying microarchitecture of an OOO 4 way superscalar MPU. What would a programming language look like if we took away the ever futher from the metal ISA and wrote much closer to the metal? Itanium perhaps?
How many physical registers in a Core duo / Athlon 64, what does the cache behave like, what groups of instructions can execute simultaneously? Would C translate well to this model? Would you really want to treat arrays and pointers the same on a machine with memory protection? What considerations would you want to make about function calls, memory allocation, stack usage? What language details would you want to add to handle the prevalence of SIMD instructions?
If C compilers could write to the metal on modern CPUs what would performance be like? I wish the Nx586 had been more successful, and we had all gotten a chance to turn off that x86 translation layer...
I think half the problem is some programmers have never worked at the embedded level, or only early processors where an instruction could be shown to be a set sequence of logical events. The disparity between modern ISA's and what is going on at the low level is growing all the time.
http://winhlp.com/WxDMA.htm
I've seen it happen multiple times on my 2000 box. A 35 MB/sec drive drops down to about 4 MB/sec. It's worst when your DVD/CD drive is on the same controller. You throw in a bad disk and windows decides that flakey things are going on and reverts you back to PIO.
A real PITA - and a good reason for always putting optical drives on their own controller.
Like the parent says - It Depends.
(1) What is the target application, does it have latency requirements? You may not want to use Java if it does - or program like your writing code for Javacard or J2ME (Create your objects at startup and don't just new yourself into GC hell).
(2) You probably want to think about the algorithm first. A 100x faster native CPU won't do much good if your algorithm is coded O(n!) vs O(n^2) on the interpreted platform.
(3) Bandwidth is money, latency is forever.
(4) It was once said that LISP / PROLOG were too memory hungry. Big Institutions could afford memories of say 4 MB and fast CPU's. Now you quite possibly have more than 5 VAX MIPS in your cellphone and more memory than that late 70's / early 80's VAX too.
Here's a final question. Suppose your requirement was to write the embedded code for a medical radiation therapy machine. The machine has to: 1) Turn on and off the beam. 2) Rotate the beam around some axis.
Screwing up could mean fatality. What language / environment would you use then? Imagine your loved one has to lie on this thing.
Java with the GC possibly getting in the way?
C? -- Pointer smashing?
C++ -- Ditto...
Lisp, Mercury, Erlang, Ada, Modula 2, Eiffel, Assembler? No software?, hardware? / a finite state machine?
Hint for googling: Therac-235.
Dude, You've obviously never shorted out a NICAD cell before. The wire turns red hot and the insulation melts. The NICAD just says 'Is that all you've got? CoMe On! FeeL the BuRn BabY!' --Tarp