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Comment: Re:Sharing Economy? (Score 1) 215

by JazzHarper (#49055875) Attached to: Japan Now Has More Car Charging Points Than Gas Stations

For comparison, a typical gasoline-powered vehicle has a storage capacity of about 500 kWh and a recharge rate of 15,000 kW. The average driver consumes the gasoline equivalent of 57 kWh per day. Taking into account the fact that gasoline engines are about 25% as efficient as electric motors, each electric car needs about 14 kWh of charge per day, on average. While a gasoline dispenser can refuel as many as 100 cars/day, a charger can only supply 3 cars/day. So, you need at least 30 times as many charging stations as gasoline pumps to support the same number of cars.

Comment: Too many attempts, try again later. (Score 1) 223

by JazzHarper (#48225917) Attached to: Passwords: Too Much and Not Enough

You don't need long passwords, just reasonably good ones, to defeat online guessing. Estimates of how quickly billions of guesses can be performed assume that all your encrypted passwords have been downloaded and can be subjected to brute force, offline. That means your security has already been compromised.

Comment: Re:Heavier than air flight is impossible (Score 4, Insightful) 350

by JazzHarper (#48173265) Attached to: The Physics of Why Cold Fusion Isn't Real

Apparently, you don't fully understand the difference between physics and engineering. Technological barriers can often be overcome with advances in materials and design. Declaring them to be insurmountable has been shown to be foolish, many times. Barriers imposed by the properties of matter, on the other hand, are much more durable. Declaring them to be insurmountable is rarely a mistake.

The Universe is populated by stable things. -- Richard Dawkins