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Comment: It's not a tank (Score 1) 163

by plsuh (#48220323) Attached to: British Army Looking For Gamers For Their Smart-Tanks

Geez how the press gets this sort of thing so wrong. It's not a tank, it's an Infantry Fighting Vehicle (IFV). It's lightly armored against small arms and small-bore auto-cannon rounds, not against ATGMs, tank main guns, or RPGs.

The weight at 34 tonnes is much less than that of any current front-line tank (according to Wikipedia the Challenger 2 is 62.5 tonnes, almost double the Scout SV). It is a lot heavier than most current IFV's (e.g., the German Marder at 28 tonnes or BMP-3 at 18.7 tonnes), but that may not be such a good thing. It makes strategic mobility more of a problem and ensures that the Scout SV can't swim across rivers by itself.

Some reporter just cut and pasted from the press release. Feh!


Comment: Full course available online (Score 4, Informative) 144

by plsuh (#47893489) Attached to: Harvard's CompSci Intro Course Boasts Record-Breaking Enrollment


My son took the course last year as a senior in high school via iTunesU.

It's also available on EdX.

Heck, I took it way back thirty-odd years ago. :-)

Also, here's a link to the original article in the Harvard Crimson:


Comment: Suggestions for the Apple technologist (Score 3, Informative) 131

by plsuh (#47608471) Attached to: Ask Slashdot: Good Technology Conferences To Attend?

In chronological order looking forward:

MacTech Boot Camps -
Small, local, inexpensive. Check to see if there's one close to you.

MacTech Conference -
Larger, both sysadmin and developer tracks

MacIT -
Larger, multiple tracks and levels of knowledge

The granddaddy of them all, but next to impossible to get into these days. Mostly developer focused. May not be useful if you don't already have a deep knowledge base.

MacAdmins -
The most education-focused of the conferences. Very knowledgeable presenters.

FWIW, I've been a presenter at MacTech Boot Camps, MacIT, and WWDC.


+ - Evernote Hit by Hackers->

Submitted by
plsuh writes "Evernote is the latest victim of an attack. According to their website,

"In our security investigation, we have found no evidence that any of the content you store in Evernote was accessed, changed or lost. We also have no evidence that any payment information for Evernote Premium or Evernote Business customers was accessed.

"The investigation has shown, however, that the individual(s) responsible were able to gain access to Evernote user information, which includes usernames, email addresses associated with Evernote accounts and encrypted passwords. Even though this information was accessed, the passwords stored by Evernote are protected by one-way encryption. (In technical terms, they are hashed and salted.)"

No indication as to the hashing mechanism — is it a simple, easily brute forced MD-5 or is it a harder, more secure PBKDF2, Bcrypt, or Scrypt with lots of rounds? Anyway, Evernote has reset the passwords of all of the affected users."

Link to Original Source

Comment: Re:$3600 ship (Score 3, Informative) 398

by Jim Haskell (#42733001) Attached to: How <em>EVE Online</em> Dealt With a 3,000-Player Battle

He didn't jump back because he was physically incapable of doing so. In Eve: Online, other ships can use ship modules on you that prevents you from leaving the area. It's called "tackling." The pilot in question, upon erroneously jumping into the system, was tackled by enemy forces before he could escape. Instead of eating the loss, he called up on his allies to jump in to attempt to destroy the ships that were tackling him. (A titan-class vessel is largely unable to destroy the much smaller Heavy Interdictor-class vessels that are capable of tackling it due to the ship's poor tracking and large guns, and requires help if it is tackled. A good analogy here is trying to kill a fly with a cannonball at 30 kilometers -- guns in Eve work similarly.)

When the pilot's allies arrived, the enemies called THEIR allies and joined the fight. With the amount of tackling ships on the field, neither party could easily escape, and things snowballed considerably. The enemy forces in this case had the upper hand of available pilots and were able to inflict heavy losses.

Comment: Re:Help an old guy understand this (Score 1) 398

by Jim Haskell (#42732935) Attached to: How <em>EVE Online</em> Dealt With a 3,000-Player Battle

You are right, but I can clarify the matter. In Eve: Online, other ships (typically your enemies) can use a ship module on you that prevents you from leaving the area, making you vulnerable to weapons fire. It's called "tackling." Tackling a titan-class vessel in Eve is difficult, requiring a special class of ship and a special weapon, but possible if you are coordinated enough and have enough espionage available to determine where your enemies will be.

Comment: Re:Net energy? (Score 1) 580

by Keeper (#41708377) Attached to: Scientists Turn Air Into Petrol

Your assertion is that green capacity is always fully utilized, which is incorrect. Your second assertion is that non-renewable capacity is also fully utilized, which is also incorrect. This process yields a benefit when there is slack capacity in the system -- cases where it is generating more power than is actually needed. Instead of wasting that energy, it can be used for some useful purpose.

Comment: Re:But that's not the real problem. (Score 1) 1651

by Keeper (#41529093) Attached to: To Encourage Biking, Lose the Helmets

There is no minimum speed limit on surface streets. You can bitch and moan about cyclists all you want, but they have a legal right to be there. Deal with it or get the law changed. Getting angry at the cyclist for "holding up traffic" is just as stupid as getting angry at school busses for stopping to pick up children or at the mailman for stopping to deliver mail.

Comment: Re:LED is freakishly expensive up front (Score 1) 1080

by Keeper (#41480425) Attached to: Light Bulb Ban Produces Hoarding In EU, FUD In U.S.

I saw your comment, but I couldn't find your data. The only information I could find regarding expected life was 25000 hours. Some examples:

"Lasts at least 22.8 years", "22.8 years means rated average life based on engineering testing and probability analysis where the lamp is used on average 3 hours/day, 7 days a week"
22.8 years * 365.25 days/year * 3 hours/day = 24983.1 hours

"The unit that I am reviewing is warm-white (2700K) and has a CRI of 80. Warranty is 6 years, and Philips rates it at 25,000 hours of operation (it should last for decades if you take good care of it)."
On picture of the box: "Life 25,000 hours"

"The LED bulb will last 25,000 hours compared with the 1,000 hours that consumers normally get out of the average 60-watt incandescent bulb."

"The next question you need to ask yourself is would you pay $40 (around £25) for a light bulb? Answer is probably not but if that light bulb was to last as it is advertised for 25,000 hours then of course."

"Other features include: instant-on, dimming capability to 10% of maximum brightness, a 25,000 hour life and a 6 year warranty."

Long-term lumen maintenance testing
Continuing to run; now > 12,000 hours
Lumen mainteance at 25,000 hours -> 99.3% (95% confidence, 200 units)

Comment: Re:LED is freakishly expensive up front (Score 1) 1080

by Keeper (#41474921) Attached to: Light Bulb Ban Produces Hoarding In EU, FUD In U.S.

I can count the number of times I've had a bulb break in a lamp after knocking it over on zero hands.

Most lamps have shades, which prevent the bulb from impacting the ground. Lamps without shades usually have some sort of glass surrounding the bulb; if the bulb breaks that glass is most certainly broken (and presents a much more expensive problem than replacing the bulb).

Finally, LEDs are plastic and are far more durable than glass bulbs. I haven't tested what kind of abuse they'll take (as I generally don't knock lamps off of tables), but I expect them to be less fragile than glass. They will certainly survive a move without damange if reasonable common sense is used (meaning that you don't use them as feet for your heaviest furniture).

LED bulbs can also be used in more locations than just table lamps as well; if the bulbs installed in your ceiling fixtures are commonly being broken by your children you've got far bigger issues on your hands than the cost of light bulbs...

Comment: Re:LED is freakishly expensive up front (Score 1) 1080

by Keeper (#41474867) Attached to: Light Bulb Ban Produces Hoarding In EU, FUD In U.S.

I think you need to work on your math a bit.

Comparing a 60w light bulb with a 12.5w led equivelent, and run it for only 4 hours per day, you break even after 3 years. If you're smart about where you install the LEDs, focusing on your most used fixtures in the house, the breakeven point will come sooner.

If the LED bulb only lasts 4 years, at 4 hours a day total cost for the LED is $31 and total cost for the incandescent is $40. You'll have to buy 4 incandencent bulbs over those 4 years ($1.76) and use 350kwh powering it (costing $38.54).

The Philips LED bulbs are actually rated for 25000 hours of use, not 5000. LED bulbs do not have the problems CFL bulbs have with lifetimes -- you can switch them on and off as much as you like and not impact their life. The only thing they're senative to is heat (meaning you shouldn't install them in closed fixtures). Several of the Philips LED bulbs in my house are probably approaching 6000 hours with no issues.

At 4 hours per day, that bulb should last for 17 years. If the bulb actually makes it that far, you'll spend $57 on the led bulb and $171.29 on the incandescent bulb. That, of course, assumes that the cost of power remains 11c per kwh. If the cost of power goes up over time, the cost disparity will increase.

Philips has a new version of their 60w bulb that consumes only 10w (its actually brighter than the existing bulb to boot!), and is rated for 30000 hours (or 20 years @ 4hr/day). Over 4 years the difference is $29 vs $40.30 (or 30% savings) per bulb, and over 20 years $78 vs $201 (or 60% savings).

LED bulbs do require non-trivial up front costs, but do result in measurable savings over the life of the bulb. And those savings will only go up as energy prices continue to rise. There are certainly reasons to continue to use incadescent bulbs, but the "it costs a lot up front" argument is rather short sighted...


+ - Intel Denies CEO Said Microsoft Is Releasing Windows 8 Prematurely

Submitted by Anonymous Coward
An anonymous reader writes "Intel today denied a rumor from earlier this week that suggested CEO Paul Otellini told employees Microsoft was releasing its Windows 8 operating system before it was fully ready. Intel referred to the hype that ensued as “unsubstantiated news reports” and quoted Otellini going on record to say that “Windows 8 is one of the best things that ever happened to Intel.”"

It was kinda like stuffing the wrong card in a computer, when you're stickin' those artificial stimulants in your arm. -- Dion, noted computer scientist