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Comment 0.74% atmospheric pressure and trace oxygen levels (Score 1) 104

To properly test a prototype, you would need to fly a prototype helicopter (probably with very large rotor and very powerful turbine) to 33,000 meters altitude on Earth to test equivalent atmospheric pressures. The current altitude record for helicopters is only 12,442 meters.

There's another major problem posed by Mars. 96% of the atmosphere is comprised of CO2 and there is only trace amounts of oxygen. That means not only would you have to carry fuel, but you would need to carry your own oxidizer as well which adds a lot of weight.

Comment Cisco is only describing the IETF standard (Score 1) 337

"A July 1999 IETF specification (RFC 2638) discusses paid prioritization by saying: “It is expected that premium traffic would be allocated a small percentage of the total network capacity, but that it would be priced much higher.” Another specification (RFC 2475) published half a year earlier says that setting different priorities for packets will “accommodate heterogeneous application requirements and user expectations” and “permit differentiated pricing of Internet service.” (An RFC is a policy document, often accepted as standards, published by the IETF.)"

I would also add that the abstract of RFC 2474 says:

“Differentiated services enhancements to the Internet protocol are intended to enable scalable service discrimination in the Internet

Comment Re:The title is a bit misleading (Score 1) 32

Capacity matters a lot in Wi-Fi as well as cellular data. Very rarely will you see mobile devices be able to leverage 2x MIMO or better because they only have one antenna. Capacity is effective peak performance for most situations. Peak throughput is great for marketing benchmarks and occasionally real life performance when it comes to wireless bridging.

Comment Re:The title is a bit misleading (Score 1) 32

MU-MIMO does effectively offer higher speeds than SU-MIMO in practice. Since most client devices are single antenna devices and only a few that are dual-antenna, MU-MIMO effectively increases the per-client throughput by improving overall capacity. If four single-antenna clients can be concurrently served by a MU-MIMO access point with 4 antennas, each client can have up to 4 times more throughput than the same 4 clients being served by a 4-antenna SU-MIMO access point. The SU-MIMO 4-antenna AP can't speed up operation for a single 1-antenna client.

Comment Re: Official cable doesn't stop dangerous chargers (Score 1) 663

I said the cables are overpriced, way overpriced I might add. It's just a freaking cable. I said the chargers at $20 aren't *that* overpriced, though they're still overpriced somewhat. The chargers that Apple sells are actually one of the highest quality chargers on the market according to this guy's tests ( so they're actually worth close to $20.

So my point is that if Apple cared about safety, they'd lock out 3rd party chargers rather than the 3rd party cables. It's the charger that's dangerous when it sends 110V or 220V AC down the USB cable.

Comment Official cable doesn't stop dangerous chargers (Score 2) 663

A person can still use an overpriced official cable from Apple but used a dangerous charger and the dangerous conductive surface of the iPhone. The cable isn't the cause of the safety issue but the cable is what's overpriced so iOS 7 is forcing you to buy the overpriced cables. The official Apple chargers aren't *that* overpriced.

Comment Re:like anything else.. (Score 1) 580

Same here. High School AP classes were just too easy compared to what they offer at the junior college. And what they offer at the junior college for the same subject is too easy compared to a major university. It doesn't feel good to get that rude awakening but the people with character admit their shortcomings and then work to overcome them.

The problem in recent decades is that we're too focused on building up the self-esteem of our youngsters. It gives them a false sense of what the real world is like and we're failing to prepare them for the real world. They think everything should be easy and effortless when they should be challenged.

Comment Re:Systematic corruption in the AGW movement (Score 1) 476

You didn't address a single issue I raised that specifically criticized the actions of Mann and the UN IPCC. You use words like "denier" to attack the opposition. Your ad hominem response is unfortunately all too typical of the AGW movement. And yes I do criticize the AGW movement based on the actions of Mann and the UN IPCC because they are central figures in the AGW movement. And when Mann and the IPCC display blatant disregard for the scientific method, it calls into question the AGW movement which heavily relies on Mann's graph and the UN IPCC.

Comment Systematic corruption in the AGW movement (Score 0) 476

Even though I'm willing to accept the idea that man probably has caused some of the warming over the last 150 years, any honest scientist will acknowledge that we can't be sure how large of a role man plays when we consider the fact that we were coming out of a little ice age. It's also disputable that we are facing "unprecedented" warming because recent studies ( show that there was significant worldwide warming during the medieval warming period.

In general, it's good to let scientific "consensus" drive policy. But when the major scientific organizations try to shut down all discussion and explain "the debate is over" and start drawing firm conclusions on something as complex as climate science, it makes me suspicious. Then when the AGW advocates start blatantly lying about how there is supposedly more incidents of extremely destructive weather and fire, it makes me extremely suspicious. When the UN IPCC knowingly makes up a story about the Himalayas melting in a few decades even though they know it's based on a single *opinion* from an activist making comments in the WWF magazine, it tells me that there is a systemic corruption of science when it comes to the issue of global warming.

And when I see proof that Mann et al is cherry picking data in a nontransparent manner and most of the "concensus" is based on that cherry picked data, this so called "concensus" no longer holds any credibility.

Submission + - Unlocked Phones: How and Why to Do It (

lseltzer writes: "Many news stories recently have discussed the politics of unlocked phones, but if you want to use one what are the practical implications? Who sells unlocked phones? What carriers let you unlock theirs and activate others? BYTE explores these issues and tells you why you might want an unlocked phone and how you'd go about buying one and getting service for it."

Submission + - Should Microsoft Switch to WebKit? ( 1

DeviceGuru writes: Although IE remains the dominant browser on desktops, it's being trounced on tablets and smartphones by browsers based on WebKit, including Safari, the Android Browser, and Google Chrome. Faced with this uphill battle on handheld mobile devices, Microsoft MVP Bill Reiss has suggested that it might be time for Microsoft to throw in the towel on Trident and switch to WebKit. But although there are lots of points in favor of doing so, there are also some good reasons not to, including security and a need for healthy competition to avoid having mobile developers begin to target WebKit rather than standards. What do Slashdot readers think?

Comment Re:x86 or ARM? (Score 1) 229

AMD might attempt some really bulky overweight tablets that have to be shut down rather than something that behaves like an always on iPad or smartphone. Then again, this applies to Intel's Ivy Bridge parts because they can't do "Connected Standby" either. A high-performance SoC with Connected Standby won't happen for Intel until Haswell in 2013. AMD on the other hand has nothing announced for 2012 or 2013 that does Connected Standby.

Comment Re:x86 or ARM? (Score 2) 229

Hondo is a Brazo based "APU" so it's definitely x86. But unlike Intel Clover Trail, AMD Hondo isn't really a tablet chip because it fundamentally lacks "Connected Standby" capability in Windows 8. That means it won't do 30 days of standby in an on state nor is it compatible of meeting the 300 millisecond screen-on requirement. Moreover, Hondo is a 4.9W TDP part while Intel Clover Trail is a 1.7W TDP part.

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