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Power-Saving Web Pages: Real Or Myth?

Johnno74 Re:Watts aren't a unit of energy. (424 comments)

In high school I'm guessing you probably worked with DC current... where the current does NOT vary over time, so the power factor is 1

With AC power the parent is correct. However I think the power factor used by most devices is over .9,

more than 2 years ago
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Power-Saving Web Pages: Real Or Myth?

Johnno74 Re:Seriously? (424 comments)

Parent is 100% correct. However I don't think you can get OLED monitors... yet. Quite a few cellphones use OLED screens though, such as my galaxy S.

OLED screens don't have a backlight at all. In an LCD screen the pixels are actually acting as filters, blocking part of the light from the backlight. In an OLED screen the pixels emit light themselves - black pixels are turned off and consume zero power.

For this reason turning the screen brightness down dramatically affects my battery life.

more than 2 years ago
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Iceland Eyes Liquid Magma As Energy Source

Johnno74 Magma is dangerous, hmmmmkay? (215 comments)

They hit magma while digging? Ouch.

If minecraft has taught me anything, it is that hitting magma unexpectedly is a Very Bad Thing.

I sincerely hope that they had a bucket of water handy to put themselves out, and that they weren't foolish enough to be digging the block they were standing on when they hit magma.

more than 3 years ago
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Google ReCAPTCHA Cracked

Johnno74 Re:Does this mean.... (211 comments)

Are you on drugs? I brought a corned beef sandwich once when I was in the UK, turns out they used spam.

I totally thought someone had put something from a can of catfood in my sandwich and I was bitching to my workmates until someone confirmed it was genuine spam.

I couldn't eat it, and I seriously doubt if my cat would have either.

more than 3 years ago
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Scientists Find Tears Are the Anti-Viagra

Johnno74 Re:Seriously (207 comments)

Problem is there is undoubtedly lots of different stuff in tears - probably many thousands of different compounds. Big job to see which compound is having that effect.

more than 3 years ago
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Playstation 3 Code Signing Cracked For Good

Johnno74 Re:Epic Fail? WTF? (534 comments)

I doubt if he was full of it... "that asshole" that you are talking about is geohot, who was part of the team behind the original iphone jailbreak & unlock, and he's also developed jailbreaks for lots of versions of IOS.

So his credentials are pretty good... he'd already proved himself at the time he started hacking the PS3.

more than 3 years ago
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Microsoft Ready To Talk Windows On ARM

Johnno74 Re:No surprise (342 comments)

I'd be very surprised if you don't own something that has an ARM core. They are _everywhere_
If you've brought a cellphone since about 2005, or brought a consumer router from linksys, buffallo, asus or many others, or most media player gadgets then you'd probably find an ARM core in them.

more than 3 years ago
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Oracle To Halve Core Count In Next Sparc Processor

Johnno74 Re:blindly pushing marketable limits... (200 comments)

IIRC the original athlon actually licensed some of the features of the alpha from DEC too...

more than 3 years ago
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Vuvuzelas Blare On Pirated Copies of Music Game

Johnno74 Re:Detection (320 comments)

Yes, once you've figured out how the checksum is generated. But once you have figured out where/how the checksum is generated you could also modify that code to always return "checksum validates" or somesuch...

more than 3 years ago
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Computer Glitch Leaves Some Australians Without Cash

Johnno74 Re:Sorry but doing that is gambling more or less (195 comments)

Read the article - you are barking up the wrong tree. The problem is people who were paid on thursday haven't had their pay go in yet. Doesn't matter what date you scheduled a payment to go out if you don't have any cash in your account because your deposits haven't been processed...

more than 3 years ago
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FedEx Misplaces Radioactive Rods

Johnno74 Re:FedEx? (165 comments)

<quote>Negative outcomes will happen in life. Get over it.</quote>

Man you really hit the nail on the head with that one. You've expressed what I see as the major problem with today's world as succinctly as I've ever seen it put before. I should make that my sig.

Everyone buys into the mainstream media/government scaremongering so badly that they have totally lost perspective of what they are giving up to mitigate what is really a tiny risk - we are so scared of things like terrorism, germs, kids having an accident/getting sick/getting snatched by a nutter that we don't really enjoy life any more.

</OldManRant>

more than 3 years ago
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Comparing Windows and Ubuntu On Netbooks

Johnno74 Re:Not very fair testing... (317 comments)

I've never understood this obsession with boot times, particuarly on a laptop with good sleep/suspend support.

Every laptop I've owned since 2001 has been very reliable at suspend/resume, taking only a couple of seconds to go to sleep or wake up.

And a full charge on the battery will last over a week on suspend.

more than 3 years ago
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Research Inches Toward Processor-Specific Malware

Johnno74 I don't get it (155 comments)

The researchers claim to be working on a tool, dubbed Proc_Scope that will use specific numerical expressions to identify the processor type, and to be working on an algorithm that can help identify a specific processor.

That all sounds quite involved and somewhat fragile.

Or you could just use the CPUID instruction. Its been around since the original pentium.

more than 3 years ago
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I drink too much...

Johnno74 Re:Tea (500 comments)

Its true, the english love to queue. My dad once said when he was in london he stopped on the street and bent down to tie his shoelaces. When he finished and stood up he saw a queue had formed behind him...
Obviously bollox, but when I was there I don't know how many times I went to the train station and there were 10-20 people queuing at one ticket window, and right next to that window there was another window only one or two people queuing up.

more than 3 years ago
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Researchers Race To Recover Radioactive Rabbits

Johnno74 Re:Recommended Reading ... (145 comments)

I suggest you chuck a large block of chocolate over the fence as a special treat for it. I hear dogs really love that stuff.

more than 3 years ago
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Flash Can Rob 2 Hours From MacBook Air's Battery Life

Johnno74 Re:Not just the Air (509 comments)

Wow, nice straw man. The registry has nothing to do with itunes suckiness. Itunes is bloated and slow. its a what, 100mb download for a fancy media player and organiser. Winamp, foobar2000, mediamonkey and pretty much every other media player I've used over the years are tons lighter, quicker and just plain work better.

I mean, itunes can't even automatically pick up new media you put in the media folder on your computer.

FWIW, the registry is NOT slow. And you don't have to "open the database" to get each setting. When you log on your registry hive is loaded into memory, and its pretty quick. However, it does suck having a bunch of programs settings stored in one binary file, and file associations on windows do suck.

more than 3 years ago
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The Science of Battlestar Galactica

Johnno74 Re:The beauty was in a lack of explanation! (465 comments)

That is also what was so good about Stargate SG1. It was quite common for a scientist-type character to say to one of the other characters "we found this gizmo on an old abandoned planet. Their technology was way ahead of ours. We have no idea how it works, but you press this button here, and this happens! Isn't that handy!"

more than 3 years ago
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The Science of Battlestar Galactica

Johnno74 Re:Doesn't matter what he did (465 comments)

At least you've got it better than australian TV.

Typically the networks here hype the shit out of upcoming shows or new seasons, highlighting the fact that it is "fast-tracked" from the US. 1/3rd of the way through the season they will without warning suddenly either miss a few weeks, or show a few re-runs of old episodes in random order, without advertising that it is a re-run. Sometimes a few new epoisodes will be shown, but the ratings probably aren't what the network hoped (because they have successfully driven away a decent proportion of their viewers)

They they will move the show to another timeslot, 11:30 on a weeknight or something. Possibly they will randomly change the timeslot each week week for a few weeks after this.

Another few weeks of this and the show will disappear without a trace, never to be mentioned again.

They have done this with supernatural, V, house, NCIS.

A lot of people here now just download torrents of shows if they like the torrent. Of course, the networks now winge that "internet is destroying us".

more than 3 years ago
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iPhone 4 Screens Break 82% More Than 3GS

Johnno74 Re:Water damage too (348 comments)

Or maybe the iphone 4 is more sensitive to water than the 3gs?

more than 3 years ago

Submissions

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Johnno74 Johnno74 writes  |  about 8 years ago

Johnno74 writes "A British aerospace engineer claims to have developed a propulsion system that has no moving parts, and uses no propellant. The system is based on known aspects of special relativity, and uses microwaves resonating inside a specially shaped container to exert an uneven force on each end of the container. Apparently the prototype weighs 15 kg, and produces a thrust of only 2 grams from a 750 watt magnetron. This doesn't sound like much, but like an ion thruster, the acceleration is constant — and Ion thrusters typically produce only a fraction of a gram of thrust, from several tens of kilowatts.

The "EmDrive" sounds perfect for manoeuvring satellites and deep space missions, manned or unmanned. The inventor doesn't seem to be a crackpot or anything, and it sounds like he's got government funding. His site is here, and New Scientist recently did an article too (subscription required :( )
This site has more details, including a picture."

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