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Comment Re:Bullshit.... (Score 1) 133

The uses for that single number are as follows:

a) Some class of people like to claim "mine is bigger", which requires a single number. While that is stupid, most people "understand" this type of reasoning.
b) Anything beyond a single number is far to complicated for the average person watching TV.

In reality, things are even more complicated, as speed and compression ratio depend both on the data being compressed, and do that independently to some degree. This means, some data may compress really well and do that fast, while other data may compress exceedingly bad, but also fast, while a third data set may compress well, but slowly and a 4th may compress badly and slow. So in reality, you need to state several numbers (speed, ratio, memory consumption) for benchmark data and in addition describe the benchmark data itself to get an idea of an algorithm's performance. If it is a lossy algorithm, it gets even more murky as then you need typically several quality measures. For video, you may get things like color accuracy, sharpness of lines, accuracy of contrast, behavior for fast moving parts, etc.

Comment Re:Bullshit.... (Score 1) 133

It depends far too much on your border conditions. For example, LZO does compress not very well, but it is fast and has only a 64kB footprint. Hence it gets used in space-probes where the choice is to compress with this or throw the data away. On the other hand, if you distribute pre-compressed software or data to multiple targets, even the difference between 15.0% and 15.1% can matter, if it is, day 15.0% in 20 seconds and 15.1 in 10 Minutes.

Hence a single score is completely unsuitable to address the "quality" of the algorithm, because there is no single benchmark scenario.

Comment Re:Bullshit.... (Score 4, Insightful) 133

There is no possibility for a useful single metric. The question does obviously not apply to the problem. Unfortunately, most journals do not accept negative results, which is one of the reasons for the sad state of affairs in CS. For those that do, the reviewers would call this one very likely "trivially obvious", which it is.

Comment Re:Red Bull (Score 1) 511

Of course it is a gateway drug! And before that, obviously sugar. Which is why sugar should urgently be outlawed!

Incidentally, sugar and fat kill a lot more people than all illegal drugs combined. And seriously, the whole concept of a "gateway drug" has been discredited quite some time ago. People will escalate to a certain level, regardless of the steps before that. But the authoritarian scum that just have to force their views on people can of course not admit anything like that.

Comment Re:Don't be silly. (Score 1) 119

I actually totally get Amazon's logic on this one. If there's only a $10 extra profit on each drone delivery (something I'm sure tons of people in range of the service would pay for in order to get their item in half an hour), and if we assume each drone operational cycle takes one hour (delivery, return, charging), then that's $240 a day. Doesn't take a lot of days to justify the cost of a drone with a return like that.

Comment Re:Every month a new battery breakthrough, but.. (Score 5, Insightful) 119

Except that you have bought them; you just haven't realized it. Energy density of li-ion batteries has grown by about 50% in the past five years. Have you seriously not noticed how cell phone and laptop battery mah ratings keep growing while they keep making the volume available for the batteries smaller?

It's big news when a new tech happens in the lab. It's not big news when the cells first roll off a production line.

Most new lab techs don't make it to commercialization. But a lucky fraction of them do, and that's the reason that you're not walking around today with a cell phone with a battery the size of a small brick.

Comment Re:More Range Needed (Score 2) 119

If everyone last person was going to be driving electric cars tomorrow, yes, that would be a problem.

Given that that's not the case, and for decades it's always going to be such that the people whose situation best suits an electric car are going to be the next ones in line to adopt them, then no, it's not a problem. You really think people can't build curbside/parking lot charging stations over the course of *decades* if there seems to be steadily growing interest in EVs?

As a side note, I don't know those exact neighborhoods in your pictures, but in my experience, most people who live in such places don't own *any* car.

Comment Re:More Range Needed (Score 1) 119

Actually, 800 is quite a sensible number. At an average speed of 60 miles per hour (aka, factoring in driving / bathroom / meal breaks), that's 13 1/2 hours of driving - a good day's drive. Throw in a few more hours driving time / a couple hundred miles more range if you charge while you're taking your breaks. Once you get that sort of range, charge speed becomes virtually irrelevant because it happens while you're sleeping (and getting ready for bed / getting up in the morning). A regular Tesla home charger could handle that sort of load.

I agree with you that a half hour charge isn't actually that onerous, but it definitely will scare off people who are used to filling up faster. And charge stations that can do half hour charges on 300 miles range (150kW+ for an efficient car, more like 250kW for a light truck) are exceedingly rare as it stands. A charger that powerful isn't some aren't some little wall box with a cord hanging off of it, it's the size of a couple soda machines put together (bigger if you add a battery buffer so that you don't need a huge power feed) that feeds so much power that its cable has to be liquid cooled and which costs around $100k installed. Ten minute charges are, of course, around three times that size. I've only ever come across mention of *one* charger in the ballpark of the required 750kW to charge a 300 mile light truck in 10 minutes - an 800kW device custom made a couple years back for the US Army Tank Command. I have no clue what it cost, but I'm guessing "Very Expensive".

I'm not saying that the problem is intractable, by any stretch, I totally believe that we're going to transition over to EVs. I just question the sort of time scales that a lot of people envision. The average car on US roads is 10 years old. Implying an average 20 year lifespan. And many cars don't get scrapped then, they just go to the third world. Even if you suddenly switch all new car manufacturing over to EVs, you're talking decades to replace them. But of course you can't just switch over like that - even if everyone was right now sold on the concept of EVs with current tech, you're talking at least a decade, possibly more, to tool up to that level of production. But of course, not everyone is right now sold on the concept of EVs with current tech.

Realistically, you're looking at maybe a 40 year transition. I hate to say that, because I love EVs, but I'm not going to just pretend that the reality is other than it is.

I'll also add that while fast chargers are big and expensive, the size and cost actually are comparable to building a gas station on a per-pump basis, and the economic argument works out for making them even if there's only a reasonable (50% or less) surcharge on the electricity sold and if they're only selling electricity a couple percent of the time. But you need to get a couple percent of the time usage to economically justify them - one person stopping for 10 minutes every few days just isn't going to cut it. And not every EV is going to stop at every charger even if they're driving on the same route - if your chargers are that far apart, then that means you're pushing people's range so much that they're not going to be comfortable driving that route. All together, this means that if you want to have fast charging infrastructure economically justifiable in an area you need high EV penetration, where several dozen EVs driving long distances will be going by each charger every day - even out in the boonies. And when you're talking at prices on the order of $100k per unit, you're no longer talking about a range where peoples' goodwill toward EVs or interest in having a loss leader outside is going to pay for them.

Basically, while busy interstate routes on the coasts and the like can economically justify them with a small fraction of a percent of people driving EVs, out in the boonies, they're going to be stuck with smaller, cheaper, slower chargers for a good while. Unless people are willing to pay a big surcharge on the electricity sold, that is (500% surcharge instead of 50% = 1/10th as many vehicles needed).

Comment Re:Minimum wage (Score 2) 119

As a plain, fact-ignoring statistic, yes. Women and men that actively follow comparable career paths have the same salaries. Of course, if you, say, take a 2 year timeout for having kids, that negatively affects your salary and your skills. But gender gap in pay in CS is a myth, which becomes obvious as soon as you look at the actual data. The Issue is that many women chose to offer less value to employers. And that is quite fine and, I expect, what they consider is the best option. It does come with a price though.

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