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Comment Actually they ARE working on some treatments. (Score 5, Informative) 409

It's not like there is some magical cure awaiting them upon arrival at Emory, there is no cure for Ebola. About the best they can hope for is palliative care, so why not just send a team to West Africa to do the same.

Actually there ARE some experimental treatments and antivirals, both general and specific to Ebola, being worked on. At Emory, in particular. (It's their business.)

In fact, according to previous reports, THIS GUY was working on them. And he had ONE dose of one of them WITH him.

Unfortunately, when he and a colleague both started showing symptoms, THIS GUY gave the ONE DOSE to the OTHER GUY.

Has he had other treatments already that might have made him more resistant than J. Random Villager? Haven't heard yet, but it sure wouldn't surprise me.

Bring this partiular guy back to the US, to the CDC facilities, shove him in a best-of-its-class isolab, and give him the best supportive care available (including more experimental stuff)? This might make sense, big time, despite the risks in transit.

Comment But seriously... (Score 1) 166

What does this story have to do with Linux?

I assume you were going for "funny".

But on the off chance you (or some reader) is asking this seriously...

Slashdot is about things that are of interest to nerds. The approval process for new drugs (which might save, enhance, damage, or end their lives) is one of those subjects.

Comment Re:Such a Waste (Score 2, Insightful) 156

What's so horrible about The Hobbit?

LOTR all had battle scenes that took up half the movies that were too long. Songs were not included and plot from the book cut to make room for action and Hollywood.

The Hobbit has songs in it and has more of a personal story and A LOT MORE of what is in the books and material from The Silimarian. The 1st hobbit was a little long, but I liked the 2nd a lot and I loved Misty Mountains which had a nice theme to it that I found lacking in LOTR.

Comment Nope. Need 250 plus margin on mountains. (Score 1) 119

But 200 miles certainly covers any and all local in-town and in-area travel possibilities, and nearly everything but very long distance travel.

Nope. You need 250 plus a safety margin - on mountains for part of the trip.

In my case that's half a commute between my Silicon Valley townhouse and my edge-of-Nevada ranch. But that's virtually the same trip as between Silicon Valley / San Francisco Bay Area and many weekend vacation spots: Lake Tahoe ski resorts, Reno gambling, gold country camping, etc.

Make a car that can do 30-mile-one-way commute efficiently and has this 250-and-chage range, and a Northern Californian who works near the coast and blows off steam near the CA/NV interface only needs ONE vehicle. (So it takes four to six hours to charge when you get there and when you get back - so what? It'll be parked longer than that anyhow.) Less and he/she needs TWO, with all the environmental impact of building both. Further, the long-range one is a gas hog by comparison.

Comment Yes it does. But... (Score 1) 119

Does a loaded F-150 even get 500 miles on a single tank of gas?

Yes, it does.

But it's a 37 galon tank.

I love everything about my F-150 Lariet EXCEPT the gas mileage (and the refusal to pan the weather map except when the vehicle is stopped). Unfortunately, when you have to haul several tons up and down a mountain or across an unpaved desert from time to time, it's hard to avoid a tradeoff in that department.

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:Outsourcing Exchange is always a PLUS (Score 1) 208

If you EVER had to do destkop support 1/3 of your calls our HELP MY PST IS CORRUPT I MUST HAVE IT ALL BACK!

It is great when the average person receives over +110 emails a day with a 100 meg quota is thrilling! People at work lose them all the time when their .pst hits 18 gigs and go all the way to SVP of IT to demand that billly gates fix it because they need every email for the past 10 years. ... ok rant off.

But with the cloud quotas and .pst files are a thing of the past. At least I would want to outsource this as these users will never accept lost as an answer.

Comment Re:The failure mode is transformer core saturation (Score 4, Interesting) 91

... the induced DC from a solar storm isn't as instantaneous as a lightning strike. It takes minutes to develop, which leaves time to disconnect the lines and affected transformers if they are properly monitored.

But ARE they monitored for DC? It's not a usual problem.

Warnings on the order of minutes might be useful if the transmission line were the only one invoved. Unfortunately, the power grid is a GRID. Lots of multiple, parallel, transmission lines, and many, many, more going elsewhere and often creating loops.

Redundancy is a good thing in most situations. But when you have to drop a high line, and don't drop all the others simultaneously, you shift the load onto those that are still connected. When you're cutting off because you're near the limit - either due to heavy load at the time or because of the DC issue - you can drive the others beyond their limits (or throw things out of sync and add a bunch of "reactive current" to the load) and create a cascading failure. (Indeed, this is how the first Great Northeast Blackout occurred: Three of a set of four high-lines crossing the St. Lawrence Seaway near Niagra tripped out, and the redistributed load put one after another generator above its limits, blowing its protective breakers and making it progressively harder on those remaining.)

Gracefully shutting down the grid is not something you do on a couple minutes' notice, even if you have a plan in place.

As I understand, the induced DC is something on the order of hundreds of volts, which is much less than the tens of thousands of volts transmitted across ordinary high voltage transmission lines; disconnecting them should not result in arcing problems across the switches.

First, the problem with the induced near-DC is not the voltage, but the current. Transformers and transmission lines have as little resistance as possible, because it's pure loss of valuable energy. The magnetizing alternating current (i.e. the part of the AC that's there all the time, not just when there's a load) is also limited by the inductance of the transformers, but that doesn't impede the direct current at all. A couple hundred "DC" (very low frequency - fractional cycle per minute) volts, induced for minutes around the loop, can drive a hysterical amount of current.

Once the transformer is saturated, most of the damage comes, not from the direct current, but from the line power, which ends up dissipating lots of energy in the transformer. Meanwhile, at these voltages and currents, the switches that interrupt the AC are largely dependent on the momentary off time as the cycle reverses to quench the arc. If, say, the event happened when the line was running at about half its rated load, the direct current will be higher than the alternating current, so there will be no off time. This can keep the current flowing even through an open breaker (while dissipating megawats IN the breaker). Interrupting DC is MUCH harder than interrupting AC.

Heck, at these voltages even interrupting AC is hard. (The video is of an interrupter where the jet of arc-suppressing gas failed for one leg.)

Comment The failure mode is transformer core saturation. (Score 5, Informative) 91

High induced votlages in open wires are a problem, but they're not the big one.

The biggie is common-mode currents in long high-voltage transmission lines adding a strong DC component to the current in the substation transformer windings - high enough that when the same-direction peak of the AC's cycle adds to it, the core saturates. Then the inductance of the transformer drops to the air-core value and no longer substantially impeeds the current.

The current skyrockets. The resistive heating of the windings (and the force on the wires from the magnetic fields) goes up with the SQUARE of the current. The windings quickly soften, distort, form shorted turns, melt, open, short out to the frame, etc. The transformer is destroyed, or committed to a self-destructive progressive failure, in just a handful of such cycles - too fast for the circuit breakers to save them (even if they DO manage to extinguish the arcs with the substantial DC component to the current.) Even if the transformer doesn't explode and throw molten metal, gigawatt sustained arcs, and burning oil (or burning-hot oil replacement) all over the substation area, it's still dead.

This happens to MANY of the giant transformers in the power grid. Each set of three transformers that has one or more failed members means a high-voltage transmission line that is shut down until the transformer is replaced.

There are essentially no spares - these are built to order. Building one takes weeks, and there are few "production lines" so little parallelism is available. What is destroyed overnight will take years to replace, while each intercity power transmission line is not functioning until the transformers at its end ARE replaced.

The current occurs because the transformers are organized in a "Y" arrangement, and the center of the Y is grounded at each end (to prevent OTHER problems). The transformers have enough extra current handling capacity to avoid saturation from the DC through that center connection to/from ground from ordinary electrical and solar storms - just not a giant one like we get every couple centuries.

The solution is to put a resistor in that ground connection, to limit the DC in the lines (and dissipate the energy it represents). Indeed, a few lines have such resistors already.

But a suitable resistor is a box about the size of one of the transformers. It's very expensive. And it only makes a substantial difference to the operation of the lines in such a once-in-centuries event. So most executives don't spend the money (and get dinged for costing the company millions) to put them in, to prevent a failure mode that hasn't happened in the generations since Tesla and Westinghouse invented the three-phase long-line power grid.

Or at least they don't until the regulators or their stockholders require it. Which means said decision-makers need a little educational push to decide it's worth the cost and get it done.

Thus articles like this. B-)

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