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Comment: Re:Well (Score 1) 594

by ninjabus (#48295415) Attached to: Space Tourism Isn't Worth Dying For
It takes a significant amount of extra energy to push through the lower atmosphere thanks to air resistance, so starting a burn at higher altitudes is ideal. In addition, acting as a plane allows the atmosphere itself to act as your propellent, further improving efficiency. Throw in the improved maneuverability on landing and you could guess why engineers would like a space plane design to work.

Comment: Re:Workforce vs. number served (Score 2) 720

This does reduce the workforce, nothing was stopping mcdonalds from implementing an order here - pay there system with two employees. Isn't that exactly how drive throughs work? It may not have been economical to do so, as people who walk into your restaurant probably have the extra time to spare.

Comment: Re:Too bad... (Score 2) 610

by ninjabus (#48140181) Attached to: Wind Power Is Cheaper Than Coal, Leaked Report Shows

Actually the peer reviewed science shows that nuclear energy has no net energy return. What this means is every dollar spent on nuclear energy is wasted. The study uses industrial standards for process measurement as a basis.

The site you linked to is bunk. They're using the 2nd law of thermodynamics to argue against mined resources. Let's see what they say: "From the Second Law follows that the generated amount of useful energy from mineral energy sources is insufficient to compensate for its coupled entropy generation, even if all useful energy would applied to that purpose." It's not possible for uranium mining to decrease entropy in the universe, so obviously it's not economically viable! You could say the same thing for breathing.

Comment: Re:Have the solutions converged? (Score 1) 77

by ninjabus (#48056159) Attached to: Supercomputing Upgrade Produces High-Resolution Storm Forecasts
Based on the resolution increase, and the difference in computing power that was needed to provide that increase, we can make a few assumptions about their algorithm. There was an increase in computing power of 2.88 times, which achieved a better predictive resolution of 16 times. This tells us that they are calculating differences based on the perimeters of their smallest resolution. Create a square on paper, call each edge 8 miles. Now divide that square into 2 mile subsections. The increase in edges you need to do this (4 vs. 10, or 2.5 times more) corresponds nicely with the 2.88 increase in computational power. This implies that the news systems are likely running the exact same model as the old ones, except with a greater contour density.

Comment: Re:Not about ease, about authority (Score 3, Informative) 231

by ninjabus (#47903185) Attached to: School Installs Biometric Fingerprint System For Cafeteria
Exactly. I paid for a school lunch using a similar account linked to a PIN 20 years ago. When a kid forgot their pin, the cashier looked their name up in a binder to enter it correctly. There is no need for account security if the maximum withdrawal rate is 1 lunch per day.

Comment: Re:Memorization, or attention to detail? (Score 1) 123

by ninjabus (#45940349) Attached to: Experiment Shows Caffeine Boosts Long Term Memory
I wouldn't be too surprised. Evolution as a tuning process is very effective, but it has issues about getting stuck in just-effective-enough configurations. We evolved to be fairly intelligent, but the body is clearly programmed for using less food energy than is currently available in modern times. There has been some speculative research linking the domestication of fire to increased brain mass. This isn't because larger brains meant we were smart enough to figure out fire, but instead because fire allowed us to digest more foods efficiently, increasing the nutrients our brains could use. Modern agriculture is another jump in nutritional availability, but our bodies haven't adapted to this yet. There could potentially be an extremely effective but inefficient neurochecmical pathway which evolution discarded because conserving energy was the strongest selective pressure, and the alternatives were simply good enough.

Comment: Re:Of course planet formation theory will need fix (Score 1) 129

This object is in an ugly middle between being a separate star or just a planet. Are there any models that consider both star and planet formation as the same process? If we built our programs to model one or the other, it's easy to see why we wouldn't have predicted distant but non-fusing binary partners. Note, it seems that 650 AU is quite distant even for a binary companion, alpha centauri A and B wobble between 16-32 or so AU between them, and have a larger orbit than most.

It is not best to swap horses while crossing the river. -- Abraham Lincoln

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