Catch up on stories from the past week (and beyond) at the Slashdot story archive

 



Forgot your password?
typodupeerror

Comment Re:Musk be a good idea (Score 1) 313

The fundamental problem with traditional car markers and BEVs is dealerships don't want to sell them. Dealers get most of their money from maintenance. BEVs require very little maintenance.
I'm yet to see a real solution to this conundrum.
Walk into a Nissan dealership and ask for the lowest emissions car they have to offer, I doubt they will point you to the LEAF. Walk into a GM/Nissan dealership and ask for a LEAF/Volt and odds are they will tell you all kinds of reasons not to buy the LEAF/Volt.

Comment Re:We need to look at cutting full time to 32 hour (Score 1) 607

You do understand that will just massively increase labour costs, giving further incentives to outsourcing...
32 hours/wk is a gift. Keep it.

The issue people can't see is productivity will keep increasing, eventually leading to a massive unemployed force.
Massive social programs are indeed inevitable, but that will only work when all countries have them, otherwise a lot of labour will jump to the countries where they don't have to pay for that.

Its the big problem with the democrat / republican polarization. Both sides have some merits, but until they can see the whole picture by accepting both sides valid points, the disfunctionality will just continue, hurting the US economy.

Comment Re:Accuracy ???? (Score 1) 350

Wrong. While GPS is very useful for long range strikes. Nuclear weapons are the least dependent on GPS, as they have substantial blast radius.
Its conventional long range weapons that need GPS the most.
Some attack weapons like tomahawk has systems that recognize landmarks and update its positioning accordingly. But ballistic weapons different.
Radar guided weapons also different.

GPS is a FORCE MULTIPLIER. Not having GPS or some similar alternative means your force lost its multiplying edge. Doesn't mean you must give up and go home, but it will be less effective in many subtle ways for us civilians, but very much in the mind of captains of the ships on both sides. One side having GPS/equivalent vs the other side not having IS significant.

Comment Re:Accuracy ???? (Score 1) 350

Long distance targeting usually involves relaying target coordinates between sensor platforms like a destroyer and its chopper, a carrier strike group and awacs radar aircraft. Coordinate grids are used.

The less accurate is your determination of where you are in the grid, the less accurate is your targeting.
Launching a sea attack against a target 50nm away usually involves telling the harpoon/whatever what bearing to fly at and how long until homing radar goes active. You want to delay activating the homing radar as long as possible to avoid alerting your enemy.
So if your coordinates might be 10nm off vs 0.1nm off you might be forced to set your weapon to go active too soon, allowing your energy to shoot it down.
Modern sea-to-sea battles involve swarm of weapons, cause your typical high tech enemy has the means to shoot at least a few incoming missiles down.

So unless you're fighting within gun range, and alone, having something ideally that gives you accurate positioning within .1nm is very important, with many shades of gray all the way to dozens of nm errors.

Its not by chance that GPS is a FORCE MULTIPLIER. Having no GPS means your force looses effectiveness.

Comment Re:Accuracy ???? (Score 1) 350

Wrong. Civilian GPS is single frequency.
Military GPS is dual frequency L1/L2 P(Y) signals.
Civilian GPS use a hack called semi codeless to do iono corrections without a second civilian signal.
L2C is still not even IOC status. It should take another decade until there are a normal 30 operational L2C sats.
The other advantage of two full military GPS bands is if one is jammed and the other isn't (unlikely but possible), then you can still get a fix in the 10 meter range.

Just because intentional degradation of L1 C/A is gone doesn't make it all the same.

Tomahawk range is hundreds of nm.
Perhaps you're talking about harpoon and other sea attack weapons, if I recall harpoon top range is 55nm, beyond line of sight for a radar fix.

Modern sea war needs accuracy in the 0.1nm range. 10nm is a very degraded mode fighting.

But continuous enhancements to INS should allow for a whole week without GPS while maintaining a 1 nm error.

Comment Accuracy ???? (Score 1) 350

Military GPS accuracy = 0.001 nm (a few yards).
Inertial accuracy = 0.1 nm / hour degradation
Celestial navigation accuracy = hundred nm
So unless GPS is gone for days, inertial is still better
That's a result of USA getting rid of LORAN which before GPS was the primary update source for inertial systems, and after GPS was fully operational switched to backup.
Celestial navigation is pretty much strictly a means to getting to the nearest port. Very limited usage for combat operations.

Comment Re:Finally! (Score 1) 182

ARM does scale.
The problem isn't ARM in general.
The problem is usually slow bus, slow ram, slow peripherals. Oh and old/slow ARM CPUs.
Take high end 8 core Cortex A57 with high end RAM and a fast bus and it will do all things you do with a Core i3 and most things you do with a Core i5.
The fact is there is very little performance ARM stuff in the market. When people get ARM they usually do because of massive cost advantages, which mean low performance implementations.
Cortex has native JAVA acceleration for instance. Most JAVA byte code runs natively on modern Cortex CPUs.
Cortex also has some natural performance advantages due to cleaner binary code. No need to be compatible with 8/16 bit modes. Just 32/64bit modes. RISC instruction set from day one. In the end that is wiped by Intel using ultra expensive much smaller gate sizes and larger caches. Which explain why ARM is sooo much cheaper than Intel without a proportional cost disadvantage.

Comment Re:Astroturf... (Score 1) 143

Radiation is everywhere.
Massive distance from radiation levels that are likely to give you cancer from actual levels @ Fukushima.
Radiation isn't like fire you can see and avoid. On the other hand radiation is everywhere.
A little radiation is proven to be good for you. Otherwise cancer levels at Denver, SLC, Aspen and Vail must be higher than in NYC or LA. In fact its the opposite.
If 20x background radiation levels were bad, there would be a serious pattern of more cancers among jet pilots than general population, last I heard, there are none.
Astronauts at the ISS get 100x normal background levels radiation even with al the shielding. OMG 100x normal background, that must be deadly. Where are the dead astronauts ? And the ones that died from cancer. Trip to the moon even higher radiation levels (outside van allen belt). Where are the dead astronauts ???
You need to go a thousand times higher than normal background levels before we can begin to argue that results in people have higher cancer risks.
Yet radiation levels in Fukushima outside the plant never got that high. Never got to ISS high radiation levels.
Chernobyl was the only serious accident because the guts of the reactor burned for days, vaporizing all kinds of nasty stuff. Still 2 million deaths was predicted, but 1000 so far (including suicide by vodka) predicted 10 thousand.
Its easy to have this anti nuclear prejudice and write everything that doesn't match your deadly expectations as a conspiracy theory.
Every new nuclear accident actually serves to prove our radiation standards are too strict. Those radiation standards are a big part of why nuclear is too expensive. We shouldn't actually need that proof, as many radiation studies already indicated that, but US NRC and other nuclear regulatory bodies are too concerned with making nuclear as expensive as possible instead of making it safe without crazy and unreasonable regulation.

Comment Re:So... (Score 1) 143

The tsunami killed 20 thousand people. A nearby oil refinery burned for days, killed dozens polluted the environment just as seriously as the nuclear reactor, but got no attention as nuclear/radiation=sensational, oil fire=boring.
The problem isn't nuclear its the media that has been bribed by fossil fuel interests to put nuclear power under a microscope while giving fossil fuels a pass.
Even if Fukushima eventually kills a hundred, it should have been a non event, as coal kills as many people every DAY ! Oil/Natural gas kills a hundred people every MONTH !
So yeah, nuclear is safe, and you're being paranoid and unfair to the facts.

Comment Re:So... (Score 1) 143

Not from radiation. Its quite hard to run around using full face masks breathing though regulators. Depending on radiation levels people are severely limited in how much time they can spend being exposed to radiation.
The fact is those standards are quite exaggerated. If radiation exposure limits were relaxed deaths could have been avoided by allowing people to do their jobs in a lesser hurry.
Tsunami killed 20 thousand people. Forced evacuation in a hurry killed hundreds. If people were allowed to stay in all likely hood far less people would die from cancer long term than died in the stress of a hurried evac (mainly elderly deaths). Or evac them more carefully.
Fear of radiation actually kills people. Radiation itself only killed in Chernobyl and some older medium severity accidents (affecting people inside the reactor building). There were also many accidents in USSR, they actually hid stuff under the rug and lied about stuff back then.

Comment There isn't enough radiation exposure (Score 1) 143

OMG ! All of this paranoia.
Radiation level was far too low to actually cause detectable increase in cancer cases.
I'm positive when this is all said and done, 10 years from now there will be no significant increase in cancer cases and no reason to believe in additional cancer deaths over normal levels.
Having small cancer formations happen to a lot of people without actually being a 'cancer case'. It could be benign, it could also not evolve into cancer (uncontrolled multiplication of cells).
Radiation safety standards are too paranoid.
Chernobyl was calculated to kill 2 million people. Instead running counter is around 1000 people (including suicide by vodka) and highest scientific peer reviewed estimates less than 10 thousand people. From 10 thousand to 2 million, that's 200x discrepancy.
TMI killed nobody and didn't cause any detectable increase in cancer levels.
So once again, the anti nuclear paranoid are creating a whole story of mass cancer cases and deaths, so once this is disproven those with anti nuclear bias can cry "conspiracy theory with tepco, japanese government and IAEA sweeping it under the rug".
From sea level radiation levels in LA or NYC to airline flying = 20x increase in radiation levels. From sea level to ISS = 100x increase in radiation levels. Yet pilots/flight attendants and astronauts aren't dying from cancer in droves. Exposure levels from Fukushima were much lower than ISS. So no cancers and no deaths.

Comment Re:So when are they making something we can AFFORD (Score 1) 323

Have you ever studied the history of industrial civilization ???
Pretty much EVERY new type of technology first comes to the market as a rich man's toy. As scale goes up, manufacturing investment pays off, processes get streamlined, you know, boring industrial engineering / economics things, price comes down.
Before the Ford Model T all cars were rich people's toys.
Then big cars were only affordable to the rich.
Then hybrids were only affordable to the upper middle class.
Although the fully loaded Tesla Model S is still very expensive, there is a 100% difference between the most basic and the top of the line Model S.
In 10-15 years I expect a Tesla Model S / X to sell for US$ 50k corrected for inflation.
The most expensive component is the battery pack, Li Ion prices will drop by half over a decade.
The other big ticket item is the electric motor, once Tesla is buying a million a yr (vs current less than 100k / yr) prices will drop substantially too.

And the more modest Tesla Model III should go for US$ 40k before incentives in 2018/2019. Should be a much better car than the Nissan LEAF, better performance, better range, at the same price.

Comment Nothing new, 10+ year old R&D area (Score 1) 163

There has been dozens of "promissing" solutions to make liquid fuels from sunlight.
Dates back to G.W.Bush mandate.
Celulosic ethanol enables making ethanol from grass and wood. Let the plants do it.
Use genetic engineering to make diesel / jet fuel like compounds from bacteria / algae.
Much like revolutionary batteries, 90% of announce techs never leads to anything commercial.
Let's focus on real technology like solar PV / solar CSP / wind turbines / improving Li Ion economics / breeder nuclear reactors.
Yes, I consider nuclear fusion another type of "promissing" technology that never gets anywhere.
However I'm always hopeful.

Comment Re: What happens when video is lost? (Score 1) 104

Nope, that's not how ATC works.
Aircraft can be re-routed.
ATC almost never looses radio.
And with the migration to ADS-B, while keeping the requirement for transponders, radar will have two completely independent parallel systems (the old transponder based and the new ADS-B/GPS based one).
ADS-B infrastructure is a LOT cheaper than secondary radar (the stuff that talk to transponders), so having everything 100% redundant is logical.
Also, secondary radar requires to be close to aircraft to allow for tight separation. ADS-B towers only need to have line of sight with aircraft to receive their signals.
But should radar fail, there are procedures to cope with that.
Throughput is greatly reduced, but aircraft can still land. In a busy airport should radar fail takeoffs might be greatly delayed.
ADS-B also allows aircraft to self separate, they see each other without need for radar. This should one day allow for much higher traffic density even in airports without towers.

Its not by accident that flying is the safest way to go. Everything is carefully though out. And technology is helping even further.
2020 ADS-B mandate is coming. ATC will know where aircraft are within a few meters, where they are going.

Slashdot Top Deals

Just about every computer on the market today runs Unix, except the Mac (and nobody cares about it). -- Bill Joy 6/21/85

Working...