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Comment Re: cellphones are bad enough (Score 1) 60

I am guessing you are making a joke. However, if keeping the roads clear of snow were a major priority in road construction, then I would advocate using waste steam from the electrical plants that are used to produce the electricity for the (plugged in) vehicles. This energy is usually wasted through a cooling tower. However, it is still useful as process heat for various purposes, like snow melting, and making some use of it increases the overall (chemical or nuclear potential energy input to electrical output) efficiency of generator plants.

Comment Re:cellphones are bad enough (Score 1) 60

You may well be right - but I think the idea is to be able to charge while you drive. Even if it is wildly inefficient and almost certainly can't give you continuous driving (at least no time soon) - it could likely extend the range of an electric vehicle by a good 30% or so, which many people would value. The cost of the infrastructure will be high but since it's value is spread over so many beneficiaries it's cost-per-user is actually quite low.

"Wildly inefficient" is the key thing. Stationary charging (e.g., cellphones) is, if you believe manufacturer's claims, up to 85% efficient. In my experience (I integrated Qi charging into a product that required no cable ports), it is more like 50-80% efficient. That much waste isn't a big deal if you are charging a phone at 5-10 W. Some things will get warm, but not too bad. It's another thing entirely when you are talking about charging an electric vehicle at 10's of kW. Even a 90% efficient inductive charger will be wasting several kW of power - comparable to an electric stovetop. (I'll note that, as far as I know, no one has demonstrated charging a vehicle in motion at anything close to 90% efficiency - so even this is a stretch.)

This would be a huge step backwards, if the goal of adopting electric vehicles is to reduce greenhouse gas emissions. Depending on whose numbers you use and how the electricity is generated, a battery electric vehicle is, emissions-wise, comparable to or a bit better than a decent gas-electric hybrid. If suddenly you slap a 50% efficiency "tax" on charging an electric vehicle, we'll not be making any progress towards reducing overall emissions.

Submission + - How to Build a TimesMachine (

necro81 writes: The NY Times has an archive, the TimesMachine, that allows users to find any article from any issue from 1851 to the present day. Most of it is shown in the original typeset context of where an article appeared on a given page — like sifting through a microfiche archive. But when original newspaper scans are 100-MB TIFF files, how can this information be conveyed in an efficient manner to the end user? These are other computational challenges are described in this blog post on how the TimesMachine was realized.

Comment Re:Free market dogwhistle (Score 1) 84

Certainly makes the case for people being able to generate their own power with a choice of utilities as a back up.

It makes the case, but that is hardly an overwhelming counter-argument. Huge numbers of electricity customers, possibly even a majority, cannot avail themselves to this. For instance: renters cannot typically put solar panels on the roof of their landlord's structure; the electrical demand for a large building is much larger than the available renewables can provide. The capital costs of self-generation - such as diesel generators or natural gas fuel cells - is quite high, and most folks simply are not cut out to manage that kind of machinery.

It's an option for some - and an increasing number of folks are availing themselves to it. This ought to be a concern for utilities generally, and for anyone who utilizes the grid (and pays for it) in any fashion.

Comment Re:record-shattering recording instruments (Score 1) 507

You, like Ted Cruz, seem to be laboring under the assumption that because it is a satellite, all rockety-spacey expensive and such, it must be better than measurements on the ground.

Satellite measurements have some advantages, such as being able to use one instrument to survey the entire Earth. On the other hand, these aren't direct measurements of temperature at ground level, in the stratosphere, or deep in the ocean; they're indirect measurements based on radiation, and have relatively large error bars compared to direct measurements. Satellite observations should not be relied upon in isolation to uphold or refute a hypothesis. We have data from multiple independent sources - they should all be utilized.

Comment Does it count as "evidence" (Score 3, Funny) 258

A computer model that predicts the existence of a ninth planet (of substantial mass, ejected into a distant orbit, early in the solar system) does not, by the usual scientific method, constitute evidence. Evidence of its existence would be certain observables that others could also observe and verify: perturbations in the orbits of other planets, detection in a telescope, etc.

This is a prediction by a hypothesis - nothing more. I could create a model that predicts the existence of dragons that fart nerve gas - that does not count as "evidence of an impending apocalypse," although that would surely generate many clicks.

Comment Re:Wow (Score 1) 216

Most of the cold "heat capacity" in the fridge comes from the chilled contents, not the air inside it. Generally, it is most efficient to have the fridge filled with lots of stuff that has a large heat capacity - replacing air volume with, say, bottles of water. Doing so will make the fridge less susceptible to, say, having the cold air replaced with warmer air. It will also reduce short-cycling of the compressor, which will extend the life of the fridge and improve its efficiency.

Comment Re:landing location (Score 3, Informative) 114

Generally, rockets begin a roll maneuver that starts them heading downrange very soon after clearing the tower. For instance, the Saturn V would perform its roll maneuver about 20-30 seconds after liftoff.

A huge fraction (90% ?) of the energy an object must gain in order to reach orbit is tangential velocity. By comparison the gain in potential energy from gaining altitude is relatively small.

Comment Re:Give us the patent number (Score 1) 174

Many corporations have policies that ban employees from looking at patents. If you look at the patent, you can later be found liable for intentional infringement. It is better to just ignore existing patents, and document your research, so you can latter show it was independently developed

Which is unfortunate, since the theory behind patents is that they should be read by others, and used as a springboard for further innovation and development. The reality is far from this ideal, alas. Most patents make for difficult reading, even if you are in the field. and, as you point out, you expose yourself to an infringement liability if you outwardly try to develop something new beyond someone else's patent.

Comment Re:Except they used regular SMS (Score 1) 291

My read on it is they mean the vendor has zero knowledge of how to break the encryption to gain access to a user's data

Oh, the vendor has plenty of knowledge on how to break the encryption - they developed it, after all - it's just that the knowledge of how the encryption works doesn't lead to any feasible way to break it in any reasonable timeframe. The knowledge the vendor has about breaking the encryption is "brute force is your only recourse, and we hope you can wait a loooong time."

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