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Ikaros Spacecraft Successfully Propelled In Space

IvyKing Re:Sad writing (and summary) (229 comments)

What do you expect with the linked article from a technically ignorant greenie publication?

Arthur C Clarke did a much better job of explaining the concept with his "Sunjammer" story that appeared in Boy's Life ca 1964.

more than 4 years ago
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An Interview With F# Creator Don Syme

IvyKing Anyone else think is was a .NET Fortran? (267 comments)

Being an old fuddy-duddy, my first thought that Microsoft was doing a dot NET version of Fortran, but...

Obvious retort is why?

more than 4 years ago
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"Home Batteries" Power Houses For a Week

IvyKing Re:Boom. (325 comments)

Good question.

The main reason why a week's energy storage would be needed is if a large fraction of the electric energy production came from wind turbines (this could be either an isolated electric grid or a customer contracted with a wind energy company). It isn't unusual for calm periods to last several days and unfortunately for those relying on electric heat, those calm periods can be the coldest days of the year.

Speaking of wind - it would make a lot of sense to have batteries that would handle one to four hours of household use, provided that the batteries could take numerous charge/discharge cycles and had a reasonable cycle efficiency. Wind generation can have large variations in output over short time periods, which stresses the grid as most generation does not like rapid variations in demand (exception being hydro). A smart grid plus household batteries would allow the load to track variations in generation as opposed to generation tracking variations in load.

more than 4 years ago
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Program To Detect Smuggled Nuclear Bombs Stalls

IvyKing Re:nuclear reactors to the rescue (224 comments)

Another way to do this would be to use a D-D neutron source, in which you will get tritium from 6Li(n,alpha)T reaction, plus you will get get tritium and 3He from the D-D reactions.

about 5 years ago
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Program To Detect Smuggled Nuclear Bombs Stalls

IvyKing Moderators don't know El Reg units... (224 comments)

Since we're talking about mouse lungfuls, either a Bulgarian airbag or Bulgarian funbag would give an answer with fewer leading zeroes.

about 5 years ago
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Cheap, Cross-Platform Electronic Circuit Simulation Software?

IvyKing You think a 286 is old and slow (211 comments)

The first time I ran SPICE was on a CDC-6400 and used punched cards for the input - and this was for a course taught by Leon Chua (of memristor fame).

more than 5 years ago
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Nanopillar Solar May Cost 10x Less Than Silicon

IvyKing What about total installation cost? (199 comments)

The cost of solars cell is low enough that infrastruture costs are a significant portion of the total installed cost. The quoted efficiency, 6%, implies that these cells would take up more area than silicon cells, and structiral support costs are proporional to area (I did see the text about possible doubling of efficiency). Another disadvantage to low efficiency cells is increased thermal loading.

more than 5 years ago
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Time Warner ToS Changes Could Mean Tiered Pricing, Throttling

IvyKing Re:Why not.... (162 comments)

Actually, the government has already made mandates about railroad pricing schemes.

I was going to make that point as well, and will add a bit to it. In the US, there are substantial advantages to be a common carrier as opposed to an industrial railroad, number being that a lot of state and local laws are pre-empted for the common carriers. In addition, eminent domain is a lot easier to secure for a comon carrier than an industrial RR.

more than 5 years ago
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R.I.P. MS-DEBUG 1981 - 2009

IvyKing MS-DEBUG?? Don't you mean SCP-DEBUG from 1980? (240 comments)

DEBUG was actually part of QDOS/86-DOS before MS thought about buying the rights from Seattle Computer Products. The DEBUG commands and syntax were similar to the features in the EPROM monitor that came with the SCP CPU's (actually on the CPU support card).

more than 5 years ago
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Oracle Won't Abandon SPARC, Says Ellison

IvyKing Re:My theory why: multiprocessors (280 comments)

In addition to that, at 3.2GHz, light in a vacuum can only travel about 9.36 centimeters per cycle. Given a dialetric constant for the Si02 used in chip manufacturing of 3.9, you can calculate the velocity of propagation of the electromagnetic waves through the Silicon as about 50.6% of C. Therefore, at 3.2 GHz, the electromagnetic waves inside the chip can only propagate about 4.7 centimeters per cycle. You also can lose a bit depending on the switching speed of the transistors, but they actually become faster the smaller they are, so the real limiter is the propagation speed.

It's actually worse than that. The 50% velocity factor you mentioned applies only if the series impedance is dominated by inductance. At the scale of the interconnects on current micro's, the series impedance is dominated by resistance and the propagation time goes up with the square of the distance (i.e. a diffusion problem). Designers will put inverters on long interconnects just to speed things up.

more than 5 years ago
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Bringing Up Bill

IvyKing Re:it figures :) (169 comments)

Slideshow works on Mozilla running on Solaris/Sparc - betcha that you don't have Flash installed.

I also wonder if Bill ever grew up.

more than 5 years ago
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TomTom Settles With Microsoft

IvyKing Patents on FAT 8.3 filenames?????? (273 comments)

The MS patents are specifically on the long file name stuff, apparently only on writing, and any patents on the original 8.3 format will have expired by now.

Since the 8.3 filename dates back to DEC's RSX-11, which was copied by CP/M, which was then copied by QDOS/86-DOS on FAT-12, it's not bloody likely that MS would have a patent on that. The idea of using FAT for QDOS/86-DOS was borrowed from MS's Disk BASIC, but I don't recall Gates or Allen patenting the FAT concept. If you're wondering what the heck is QDOS/86-DOS, it was bought by MS in 1981 and renamed MS-DOS.

more than 5 years ago
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Botnet Worm Targets DSL Modems and Routers

IvyKing Re:Tomato (272 comments)

Note that with a strong root password and usage of a non-standard port will help keep the bots away. Even better if you disable password authentication for SSH and use a key instead.

Even better yet would be setting up a user acount with a non-common name and su'ing or sudo'ing to do the administrative stuff. As an example, both OpenBSD and Solaris default to blocking root access by ssh. Another nifty ssh trick is to set it up sshd to drop most connection attempts after two attempts in a minute.

more than 5 years ago
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How the Economy Is Changing Clean Energy

IvyKing Re:Gah - energy was mentioned so the nukes come ou (227 comments)

You didn't notice above

Pebble bed is an exception

As a matter of fact I did notice that statement and I think it is absolutely wrong. A pebble bed reactor would be even easier to use for making weapons Plutonium than a light water reactor - you can pull pebbles out of the reactor without having to shut it down, whereas refueling in an LWR is done only once every 12 to 18 months. Probably the only reactor design that would be less useful for generating weapons grade Plutonium is the Integral Fast Reactor.

FWIW, the pebble bed reactor is based in part on the High Temperature Gas cooled Reactor (HTGR), sharing the helium coolant and graphite encapsulated fuel.

The Russians paticularly had a lot to say about the problems in their plants and used Westinghouse as a swear word to describe US plants with problems.

Considering the relative safety record of US naval and power reactors versus Soviet naval and power reactors, I wouldn't put much faith in what the Russians think of the Westinghouse designs (which are the basis for the majority of world's nuclear generation capacity). The US nuclear generation is now runnng at ~90% capacity factor, which speaks well for the future of the light water reactors.

more than 5 years ago
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How the Economy Is Changing Clean Energy

IvyKing Re:Gah - energy was mentioned so the nukes come ou (227 comments)

FWIW, I do have a degree in Nuclear Engineering and I know what I'm talking about with what's in the spent fuel from light water reactors. The proliferation potential from the pebble bed reactors isn't that much different from an LWR.

What is closer to dual use is the CANDU reactor, using natural uranium and a relatively low burnup (much lower 240Pu concentration). It also has provisions for on-line refueling, so it would be possible to have low burnup fuel elements to further reduce 240Pu concentration. The CANDU reactor cannot be licensed in the US due to it having a positive moderator temperature coefficient of reactivity. BTW, if you do not know the signifigance of 240Pu, you have no business making comments about "dual use".

more than 5 years ago
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How the Economy Is Changing Clean Energy

IvyKing Re:Improvements in efficiency (227 comments)

Long-haul trucking and rail freight do not substitute for each other, and attempting to duplicate the highway system with trackage would run into many and obvious obstacles. Rail freight is also usually much slower.

The Interstate highway system is pretty much a duplication of existing rail lines, there are few stretches of the Interstate system that do not parallel a rail line.

What may end up killing long haul trucking would be a tightening of emission regulations, especially wrt NOx and particulates. Rail lines can be converted to electric operation where the technology for long distance electric frieght operation was first demonstrated in the 1907 to 1917 time frame (NYNH&HRR for the earlier date and CM&StP for the later date). As a matter of fact, the Southern California Regional Rail authority was holding hearings in 1991-2 on electrifying the freight RR's in order to reduce emissions.

more than 5 years ago
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How the Economy Is Changing Clean Energy

IvyKing Re:"Clean" coal (227 comments)

There's not very many trees or much grass in the desert, where solar is most applicable.

The desert biosphere is much more fragile than most biospheres with abundant trees and grass, e.g. a ten to fifteen foot tall ocotillo bush can be well over 100 years old. There are also quite a few rare and endangered species in the deserts, e.g. the pupfish in pools near Death Valley.

more than 5 years ago
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How the Economy Is Changing Clean Energy

IvyKing Re:Gah - energy was mentioned so the nukes come ou (227 comments)

If we had civilian nuclear plants that were good at producing electricity I would agree with you. Unfortunately in nearly every case we have a compromise dual use plant that produces very expensive electricity along with the weapon materials.

The only "dual-use" nuclear power plant in the US was the Hanford 'N' reactor which was shut down shortly after the Chernobyl accident. Light water reactors are poor sources of materials for weapons due to the high 240Pu, and will be even poorer with the high burnup fuels.

more than 5 years ago
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How the Economy Is Changing Clean Energy

IvyKing Re:Innovation and Risk? (227 comments)

CO2 also burbs as it did in Lake Nyos, Africa killing almost 2000 people. Other burbs have killed more people as well as animals.

Irrelavant. The blurbs came from an area that was already leaking CO2, where a natural gas reservoir would not be a source of natural gas if it was leaking. Many of these reservoirs also contained a significant amount of helium, which is much harder to contain than either methane or CO2.

more than 5 years ago
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How the Economy Is Changing Clean Energy

IvyKing Re:Innovation and Risk? (227 comments)

The sheer amount of CO2 produced from coal is also a huge problem. It would require massive pipelines to dispose of the CO2 from areas that don't have the geology for storing it, and then there's the danger of a fissure opening up somewhere and the CO2 escaping, which would be deadly.

Natural gas reservoirs have contained the gas for millions of years, so it is fair to say that the technology exists to sequester CO2 on a geologic time scale. The reservoirs are far enough below the surface that any leaks would be a slow process.

There's also some talk about needing the CO2 to combat a future Ice Age due to changes in the earth's orbit and where the earth's axis is pointing at perihelion and apohelion.

more than 5 years ago

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