Slashdot Mirror
Slashback: Scramjet, Golden Ears, Preciousness
Everything that rises must come down under. spam-it-to-me-baby writes: "The Australian trial of a scramjet engine has fizzed. 'The experiment at the Department of Defence's Woomera Prohibited Area, 500 kilometres north of Adelaide, was not successful because the [United States-supplied] rocket experienced flight anomalies prior to the scramjet experiment,' an analysis of what went wrong says. Not to worry, another test is tentatively scheduled for next week, assuming researchers can work out what went wrong with this one on the way up."
Not to be confused with this previous scramjet test, also unsuccessful.
Ah, much better, I thought you were being unreasonable there for a minute. After Jamie drew attention to it in a Slashdot piece on Saturday, SafeSurf changed their legislative proposal. In Jamie's words, "Woo!"
That's not all he said, of course: "Please note that, now, they ONLY want to fine you thousands of dollars for failing to label anything you write that is harmful to an 8-year-old. What a relief! "The penalty for a first offense of failing to label or mislabeling material harmful to minors shall be limited to a fine of under five thousand dollars."
Bennett Haselton passed on this commentary as well:
"If you go to http://www.safesurf.com/online.htm in Netscape and "View Document Info", it shows it was last modified on October 29, 2001. (This function doesn't work in IE.)The original OCPA is [at google]. SafeSurf apparently removed this paragraph from section 6:
Publishers may be sued in civil court by any parent who feels their children were harmed by the data negligently published. The parents shall be given presumption in all cases and do not have to prove that the content actually produced harm to their child, only that the material was severe enough to reasonably be considered to have needed a rating label to protect children.and replaced it with:Publishers may be sued in civil court by any parent who feels their children were harmed by the data negligently published. The parents/plantiffs shall be given presumption, if the case involves graphic images, and do not have to prove that the content actually produced harm to their child, only that the material was severe enough to reasonably be considered to have needed a rating label to protect children.and then added three new paragraphs listing more exemptions from this rule."
Can you hear that pea through the mattresses? For the audio objectivists, a good update to CmdrTaco's recent MP3 v. Ogg Vorbis inquiry: E1ven writes: "Everyone is always arguing about whether Vorbis sounds better than MP3, or vice versa. Here is your chance to see who is right! ff123 is doing a set of Blind Listening tests and could use your help. The more ears the better!"
whats going on with the land of the free? we're always told about the fact that in the US you're innocent until proven guilty.
maybe in the economic downturn we can't afford to wait before you're guilty.
I must be missing something, because without proof of harm, the kids wouldn't even need to see it! make money via surfing the web, I guess the offers were true...
Since Ogg Vorbis got another mention, it may be worth mentioning that Croteam, creators of the surprise hit 3D shooter, Serious Sam, have announced that their upcoming sequel will have its music encoded using Ogg Vorbis, replacing MP3. Writes Alen Ladavac, "We've tried encoding all the music for SE with Oggdrop at 64kbps and the quality was perfect even at such low bitrate."
I submitted this to Slashdot two weeks ago, and it was rejected. (Hence, "Sore Loser" in the title.)
Schwab
Editor, A1-AAA AmeriCaptions
Having been in school for many years, I would think many things that people would come across in school would be more harmful than a lot of the things that can be found on the net. Yes, pr0n would fall under the category of harmful (and no, its one of the few that you're not exposed to in public school). For example, my social studies teacher showed a movie about the Civil War (I want to say "Glory" was the title.), but anyway, she got yelled at by many parents because it contained graphic images of a soldier getting his head blown up.
Welcome to the real world kiddies, violence happens and there isn't ANYTHING that you can do to stop it. I don't agree with the bill, as it would allow too many oo-they-have-money-so-lets-sue-them parents to take internet sites to court. And, it is especially bad for the children. When they get out to the real world, their parents won't be there anymore to sheild their eyes from the horrors of reality. Better let them see it while you're still there to explain it, than let them get smacked upside the head with reality when they turn 18 and/or go to college.
Honestly, this falls under the category of "political correctness." IMO, the world could use more political incorrectness. Also, by making it an offense to publish "harmful" material, it would drive more and more web hosting out of the USA, such that they couldn't be punished under that bill. In this economy and the shaky tech market, the last thing we need is to drive more business away from the USA.
We have freedom of speech? Not if any laws like these go into effect.
<SARCASM> (Note: Companies may like to check into the constitution before proposing legislation) </SARCASM>
The National Coalition Against Censorship (NCAC) has an excellent paper which details exactly what "harmful to minors" means.
That's a pretty crappy test criteria-- limiting the input to 128kbit/sec-- for those of us itnerested in achieving as-close-to-CD-as-possible performance from our compressed music.
I don't claim to have golden ears, but I can distinctly hear the difference between different playback engines (example; on a Mac, the Audion playback engine is considerable better sounding than iTunes) and different encoding engines with nearly the same settings (LAME is, by far and away, the best I have heard yet).
In any case, it would be useful to have an expanded test that includes higher bitrates for those that listen to tunes on something other than crappy computer speakers.
Ogg vs. LAME article
An excellent Ars article that only covers differences between mp3 encoders.
MP3 tech has a bunch of useful resources.
One of the best sites around, r3mix offers a wealth of technical information, some very well executed scientific and listening tests, and a section that destroys a lot of the myths surrounding mp3s.
As long as they pass the PCGA (Protection of Children from Government Act) at the same time. Here's my proposed text for the PCGA:
What do you think? Unanimous support in Congress?
Cheers
-b
If I wanted a sig I would have filled in that stupid box.
To my surprise, they responded later the same day:
OK, sounds good. I responded to Ray as follows (two days ago), but have not yet received a reply:
Make of this what you will. I still have not seen the "open and truthful" list of websites that Safesurf's software blocks.
Edith Keeler Must Die
The Safesurf MAPS rant complains about them stealth-blocking websites that may contain important information, and people won't know they're being censored. But they've got the technology wrong: MAPS doesn't block websites - they provide tools that are normally used for blocking emails and furthermore, sites that implement MAPS tools properly normally provide bouncegrams telling people they block how and why their email was rejected, so they can fix their problems. The only way a company like Safesurf would be "censored" by a MAPS-using mailbox service would be if they sent out email to people - and since they'd find out they had a problem the first time they tried to send mail, they could put a notice on their website about it and tell people who want followup communications from them how to contact them.
Furthermore, Safesurf's web site violates Safesurf's proposed law creating (and mixing up) civil and criminal penalties and tort liability for mislabeling or failing to label web sites. Their original proposal was more aggressive than their current one, but it still doesn't require any actual harm to any actual child, as long as there are graphic images on the site (logos and decorations may not be harmful, but they're graphics, so we're covered there.) Plaintiffs can sue if the site doesn't provide appropriate ratings labels on material severe enough to be potentially harmful to children. Certainly, any proposal to throw people in jail for what they write on the net is pretty severe, and could cause harm to children who write things without labeling them if such a law were passed, and telling kids that people want to do that kind of harm to them just for what they write, even if there's no law passed, can also be pretty scary. www.safesurf.com's label says
"CONTENT='(PICS-1.1 "http://www.classify.org/safesurf/" l r (SS~~000 1))'"
which if you look it up on the explanatory web site doesn't have any indication of what the rating means. It does point to a site that tells you how to download a ".rat" file into your browser, and if you open up that file with a text editor instead of installing it, the file indicates something about "all ages", but doesn't indicate whether it's appropriate or inappropriate for all ages, so that a web browser could be set to do the appropriate thing with it, though it clearly implies that the really scary material complained about above should be appropriate for all ages....
"http://www.w3.org/TR/REC-PICS-services" has more PICS explanations.
Update - their web page indicates that MAPS has now unblocked them.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
Just a general note on those scramjet tests. The guy in charge of these (Allan Paull) is my PhD supervisor, and I've been working in this area for about 4 years, though I'm not working on this project (I'm in Germany at the moment).
1. The tests were a failure in that supersonic combustion did not happen- That is, the engine operated as a ramjet rather than a scramjet. The first thought is that this was caused by the failure of the rocket turning manoeuvre, so that the air was entering the engine at a large angle from the main axis of the engine. Since the engine used has been tested up to 4 degrees of deviation, the angle was probably more than 4 degrees. The rocket needs to be turned so that it is facing downwards with the engine on the front. It should be able to do this due to the atmospheric pressure, but it turns out that it doesn't happen quickly enough. The rocket is a spin-stabilised type (Where the whole rocket spins, rather than have a separate gyroscope), and this means that the turning manoeuvre is a difficult problem in 3-D geometry.
2. Generally speaking, nobody (That I've heard of) in the scientific world is seriously looking at scramjets for a passenger plane. Amongst other thing, rockets have an unacceptable failure rate for general civilian flight.
3. The main proposal that I've heard is for a lifter of payloads in the one tonne range to near earth orbits. For that, scramjets should be cheaper than rockets. For the large payloads, rockets are still cheaper. There is a slight advantage with scramjets in that since most of the acceleration is done horizontally in the atmosphere, that a polar orbit is no more difficult to achieve than one on the equatorial plane.
4. In addition, though I'm sure there is research into scramjets for missiles (Of course it's not published in the open literature), there's not really a burning need to build faster missiles, since nobody is building faster planes or faster houses. Note also, that due to the air inlets, that a scramjet missile is inherently less stealthy than a rocket missile.
5. Somebody mentioned some tests in Russia. If these are the CIAM/NASA tests, then the papers I've read show all three flights operating primarily, in subsonic combustion mode. As ramjets.
6. One good reason for working in this field is because it is a discipline which brings together a lot of things that are also of use elsewhere. A lot of work is done on understanding the basic science, which feeds back into other areas. It's not really a field with a purely practical thrust at present, due to a continuing problem of not really understanding the aerodynamics at these speeds.
7. Thus the experiment which just failed was never really meant to be a working engine, but more a simplified example to use as a calibration for wind tunnels, and computer codes.
8. They used the terrier-orion rockets because Astrotech offered two of them for free. They have to get two tests under their belt before they can be generally licensed for testing in Australia. C/F new launch port at Christmas Island.
That's about all I can think of for the moment. The URL for the Hyshot project is:
http://www.mech.uq.edu.au/hyper/hyshot/