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Comment SAK is a worker union stuck in 1970's (Score 4, Informative) 723

I live in Finland, so few comments about the SAK.

SAK is worker union that has jammed to 1970's.

There are only 2 things SAK is capable of doing:

1) Shouting "bigger pays of we will go to strike"
2) Shouting "you may not do any improvements for more flexible work contracts, or we will go to strike".

Absolutely no understanding that the world economy has changed since 1970's, and absolutely no understanding od thet fact that finland has been belonginf to EU for over 20 years should make things very different than things were in 1970s.

Also absolutely no understanding of the fact that Nokia was holding Finnish economy high and now when Nokia is no longer making mobile phones, Finnish economy is doing much worse and they cannot require so high wages anymore.

In Finland the worker unions are way too strong, they have some rights (or actually wrongs) worker unions in other countries do not have:

1) The worker unions also decide how much is paid to employers that are not members of the union.
2) You get tax rebates for belonging to worker union.
3) In order to get better unemployment benefits you HAVE to belong to some unemployment fund, even though only about 1% of the unemployment compensation money comes from the unemployment fund, 99% comes directly from the goverment. Most of these unemployment funds are ran by the worker unions. (fortunately there is also one private on, "YTK", "common unemployment fund", but many people do not know it exists)

Comment This is not a serious issue. This is very minor (Score 5, Informative) 139

Falcon 9 and the space shuttle are the only rockets whose engines have survived the launch so that they could have been inspected. And similar cracks have been found on shuttle engines too. Many other rocket engines very probbly have generated similar cracks during their burn, but those have not been inspected because the engines have gone to the bottom of the ocean.

There have been 28 launches of falcon. During those 28 launches, 279 Merlin 1-series engines have been used, with only 1 major engine problem. And even in that case, the rocket delivered the primary payload to the desired orbit; Each falcon 9 has 10 engines and only on of those 10 engines is critical whose failure leads to mission failure.

So, until now, the engines have had 99.64% reliability, and due the engine redundancy, only 10% of engine failures means mission failure on most launches(upper stage engine may not fail), meaning mission failure probability of 0.04% due failing engine if the engines keep working equally well in the future than they previously have been working.

No, the this turbine thing is not a big problem. Bigger problems are elsewhere, and spaceX is improving the turbine blades. They will continue launching the version with the weak turbine blanes for some time, and it's very unlikely it will cause ANY problems at all, and then later the will release the block 5 model of the rocket with more robust turbine blades.

It seem that the whole issue is "leaked" by some guy who is pissed to spaceX/Elon for something and the media is always eager to post this kind of "leaks" without really understanding what it is all about.

Comment He bought the wrong jet (Score 1) 288

Hawthorne airfield is 1511 meters.

His Gulfstream G650 requires about 2000 meters in full load to take off, but can land in less than one km.

Dassault Falcon 7X needs 1750 meters to take off in full load, and can land in less than one km.

So Hawthorne airfield is not enough for G650, but Dassault Falcon 7X with tanks filled only to half could propably takeoff from Hawthorne,
and could still fly to anywhere in North America, only when flying to other continents it would have to be refuelled.

Comment Proper (instead of broken) 2-stage needed (Score 2) 637

In Finland we have a true multi-party system, not a broken 2-party system. Currently we have 8 different parties in our congress, and 3 parties in our goverment.

One important thing that makes our electoral system work is 2-stage presidential elections - and the american pre-elections are not proper first stage.

How our presidential election system works:

1) Each party selects it's own candidates (could still use similar system than your pre-elections, but it's outside the system)
2) People Vote for first round.
2a) If someone gets >50% of the votes, he/she gets elected immediately.
2b) If nobody gets >50% of the votes, the 2 candidates who got most votes go to second round, people vote for the second round. The one who get more votes wins.

This eliminates the "I most vote for someone because he is the only one who can beat this on I really don't want to be the president" thing on first round, everyone can vote for their true candidate on th first round.

Comment Cheaper than Soyuz, and lifts much more (Score 3, Informative) 121

Soyuz rocket launch cost is 48-61 millions depending on configuration (LEO launches cheaper due no upper stage)
Soyuz capasity to is 8.2 tonnes to LEO and 3.25 tonnes to GTO.

Falcon 9 expendable capasity is 22.8 tonnes to LEO and 8.3 tonnes to GTO,
and Falcon 9(stage 1 recoverable) capasity is over 13 tonnes to LEO(propably much more) and 5.5 tonnes to GTO.

So, falcon 9 on fully expendable mode lifts over 2.5x more than soyuz, and falcon 9 on stage 1 recoverable mode lift over 1.5 x more than soyuz.

This means that:
for LEO launches, reused reusable(assuming the 30% discount) falcon 9 is 10% cheaper than Soyuz, while lifting over 1.5 times more.
for GTO launches, reused reusable(assuming the 30% discount) falcon 9 is 29% cheaper than Soyuz, while lifting about 1.7 times more.

Comment No it does not compete with Skylake, those are GPU (Score 4, Informative) 84

The "deep learning" benchmark is a GPGPU workload which does practically nothing on CPU.

Nvidia has just made a SoC Chip that has about equally fast iGPU than what Intel has, for a lower energy consumption.

But in CPU performance, the Skylake is MUCH faster.

Comment RAM latency is not getting much faster (Score 4, Informative) 92

The latency of RAM is improving very slowly, only something like 2x-4x improvement in last 20 years.

Only the bandwidth of the memory is growing faster, and that's just because they have been putting more dram cells in parallel, always doing bigger data transfers and having faster memory bus.

Same is true for hard disk drive speed, the rotation speeds dictates the random access latency and the rotation speed of average hard disk has only gone up from 4200 or 5400 to 7200 rpm in the last 20 years, meaning only 1.7 or 1.33 times improvement in random access latency

  Though replacing hard disks with flash-based SSD storage has improved latency by a huge margin.

Comment Jets are much slower than A-10 bullets (Score 5, Informative) 502

The A-10 flies at about 420 MPH. Even 1980s fighter jets fly at mach 2, about the same speed as the bullets from the A-10 gun. An A-10 going after a fighter is literally the same ratio as a scooter going after a Ferrari.

Don't misunderstand, scooters are good. They are useless for chasing down sports cars, and an A-10 is just as useless for engaging enemy fighters. The fighters would (and do) fly by as if the A-10 is standing still.

Actually, even fighters from 1950's can fly at mach 2, BUT:
Even those 1980's fighters won't be flying at mach 2 at 95% of their time. They can only fly at mach 2 at high altitudes on straight line, full afterburner, wasting huge amount of duel.

Practically all dogfights happen at subsonic velocities. When you start doing high-g manouvers the velocity drops to subsonic very quickly.

> no known aircraft can survive the A-10's gun. It is the most powerful dogfight cannon

The bullets from the A-10's gun go about the same speed as the fighter. So if somehow, magically, the A-10 got on the fighter's tail and fired, the bullet probably couldn't catch up to the fighter. If it was fired off angle, it might hit the fighter at 30 MPH relative speed - not enough to dent the sheetmetal.

Survive that A-10s gun? No jet fighter in the last 40 years can be HIT by the A-10 gun unless the fighter is either a) parked or b) intentionally flying toward the A-10 without shooting it down.

This part is so incorrect....

The speed of bullets from GAU-8 is 1070 m/s.
Top speed of the worlds fastest jet fighter(mig-25) is ~890m/s flying on straight line on high altitude, with afterburner, but only ~333 m/s on low altitude.
Top speed of most modern jet fighters is in the class of 700m/s. (high, straigt line, full afterburner)

Common speed of modern jet fighters during dogfight is about 250-350m/s , 3-4 times slower than the bullets from GAU-8.

A-10 is actually quite good plane for shooting down slow low-flying aircrafts such as helicopters. It can use AIM-9 missile from slightly longer range, and from the close range the GAU-8 is very deadly. And because it can fly lower and slower it can more easily hit those slow low-flying targets than faster, higher-flying aircrafts can.

Comment Re:Unfair T/W ratio and wing loading comparison (Score 5, Insightful) 732

So what you're saying is that the plane is incapable of dogfighting unless you throw away one of the design requirements?


Here is an example. The numbers are from hat, not actual numbers.

You go to fight 600 miles away. You load the F-35 to it's full internal fuel load. When you arrive to the fighting location, you now have 50% fuel in your tanks, and you have the same T/W and wing loading ratios than in the report.

You also go to fight 600 miles away in F-16. You load it's internal tanks full, AND add two drop tanks. When you arrive to the location, your external tanks are empty, and you drop then. You are then fighting with full internal fuel load. Now, your real-world performance is WORSE than the numbers in the report, because you are fighting with full fuel tanks instead of half fuel tanks, and the report used fuel tanks that were half empty, half full.

Or, you go to fight 300 miles away. You load F-35 to half of it's internal fuel load. When you arrive the fighting location, you have 25% fuel in your fuel tanks, and you have much better T/W and wing loading ratios than in the report, as the report fuel tanks that were half empty, half full.

or, you load F-16 to it's full internal fuel load, and when you arrive to the fighting locaiton, you have 50% fuel left in your tanks, and you have the same T/W and wing loading ratios than in the report.

In all real-world cases, you have have smaller relative amount of fuel in your fuel tanks in F-35 than in F-16, and the numbers will shift in favour of F-35.

The design requirements say that F-35 has to fly a long distance with internal fuel, and that's just to make it stealthy, but not needing to use external fuel tanks.

Comment Unfair T/W ratio and wing loading comparison (Score 5, Interesting) 732

So they did their thrust/weight and wing loading comparison by loading all jets with 50% of internal fuel.

This comparison favours planes with small internal fuel tanks.

F-35 has huge internal fuel tanks, it can fly much longer with internal fuel than most other jet fighters (which need external fuel tanks, which are NOT calculated in these numbers) to fly as far.

Load all jets with amount of fuel that makes them fly about equally far and the numbers switch considerably, on favour of F-35.

Comment This article is ignoring Micron Automata (Score 1) 112

Micron Automata can solve NP-hard programs very quickly, and it's not quantum computer.

It abandons the Von Neumann model we have been using or last 60 years and can achieve very high parallelism.
And it requires a very different style of programming.

But it's not quantum computer. And it's actually working, running in Micron's labs and very soon coming to market.

Quantum computers are hype that's not really working, Micron automata is the real thing achieving mostly the same benefits.

Comment Wirth's law protects us from singularity (Score 3, Interesting) 181

There will never be enough processing power to create powerful enough AI that singularity will happen.

Wirth's law states that software gets slower due bloatness faster than Moore's law allows hardware to get faster.

We have moved from handcoded assemly and simple binary data format format to javascript which is either interpreted very slowly, or JIT-compiled into slightly faster code which is still 10 times slower than assembly, and XML or JSON-based data formats (which require a LOT of parsing). Now other languages are being complied to javascript, which adds another slowness layer on top of it.

So, it we invented a super-powerful AI that would be capable of creating truely smart code, it would spend it's time creating even more bloaty abstraction layers on top of each others, instead of creating anything that would be truely more intelligent.

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