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Comment: Education Tool for Cluster Programming (Score 1) 68

by tempmpi (#49273207) Attached to: GCHQ Builds a Raspberry Pi Super Computer Cluster

The PI uses 4 watts, so a cluster of 64 PIs will use around 256 Watt. A NVidia GTX960 will provide 2,308 GFLOPS at 120 Watt or around 20 GFlops per watt. GTX980 is even better with 28 GFLOPS per Watt. Adapteva Epiphany-IV is supposed to do 100 Gflops at 2 Watt.
Tegra X-1 can do 512 GFlops at likely something between 5-10 Watts.

But even if you would build a Tegra X-1 cluster, for many applications it would still be less power efficient than a smaller number of more powerful machines with a good interconnect:
Even most parallel applications need some communication and exchange of results between the different threads. This will be very slow on the rasberry cluster.

But a rasberry pi cluster should be a good educational tool to teach cluster programming. Processing speed is slow, communication is also slow but the ratio between communication bandwidth and processing speed is likely quite similar to real clusters. So the skills that you learn when mapping small problems to a rasberry pi clusters can also be applied when mapping big problems to real clusters. And at the same time building one of these clusters is around the same price as a single compute node in a real cluster. So you can easily give students access to such a cluster.

You could solve the small problems way more efficiently using a single GPU, but if you want to solve the big problems a single machine is not going to be enough and you will have to deal with the limted communication bandwidth between the nodes.

Comment: ECG and blood pressure monitoring needed! (Score 1) 134

by tempmpi (#49179705) Attached to: Treadmill Performance Predicts Mortality

In these fitness tests they monitor blood pressure and ECG and will stop you if your blood pressure gets too high or the ECG shows that your heart does not get enough oxygen anymore. For that reason persons can easily overestimate both maximum MET and maximum heart rate. People can reach higher running speeds and heart rates but will put their heart in danger by doing so.

Comment: Re:No, it's not even possible (Score 4, Insightful) 181

by tempmpi (#48523715) Attached to: Do you worry about the singularity?

Moore's law is on life support since a few years already. In 14nm process the smallest structures are approximately 60 Si-atoms wide. 11 doublings would need transistors structures that are only 0.03 si-atoms wide. 17 doublings would need structures smaller than 0.00045 si Atoms. It is extremely unlikely that processor improvement will continue at historical levels. It is already much slower than it used to be.

Comment: Does not have to be exclusive to be christian (Score 2) 447

by tempmpi (#48130521) Attached to: Statisticians Uncover What Makes For a Stable Marriage

Too bad basic literacy isn't part of your religion. The original poster specifically called marriage a "Christian tradition."

It certainly is a Christian tradition, but it is clearly not a exclusively Christian tradition. Just like "Honour your father and mother" is clearly a Christian value, it clearly is not a value that is exclusive to Christianity.

Comment: Maxwell instead of Keppler (Score 2) 29

how about 870M being BETTER in almost EVERY single parameter than 970M?

The 970M is based on Maxwell instead of the Kepler architecture of 870M. It is going to be a lot faster than the 870M despite having a lower number of shaders and a lower clock speed.

There are several reasons for this. In Maxwell memory access is more effective: There is a improved framebuffer compression that increases effective bandwidth by around 25%. L2 cache is now 2 MB instead of 768 KB in 870M. The next and likely more important change are more efficient gpu cores. 970M has 10 SMM cores with 128 Shaders each while 870M has 7 SMX cores with 192 Shaders each. Despite 50% less shaders per core each SMM is ~90% as fast as a SMX. NVidia did many microarchitectural enhancements such as improved instruction scheduling and shorter pipelines.

GTX970 is a about as fast as GTX780 Ti despite having 40% less shaders, 50% less memory bandwidth and only 26% higher clock.

Comment: Re:BMI is a lie! (Score 1) 329

by tempmpi (#46966127) Attached to: Gaining On the US: Most Europeans To Be Overweight By 2030

It can falsely flag you as overweight, but if it marks you obese you have a serious problems.

It depends. Overweight seems to be very healthy and results in a quite significant reduction of mortality. Obesity class I (BMI 30-35) seems to still provide a slightly lower mortality than normal weight. "BMI and mortality: results from a national longitudinal study of Canadian adults." So do you also consider normal weight to be a serious problem?

Comment: Re:have a high H1B minwage / let them work anywher (Score 1) 566

by tempmpi (#46947285) Attached to: Let Spouses of H-1B Visa Holders Work In US, Says White House

I've seen plenty of people on /. decrying the fact that H-1B workers are horribly underpaid. Having met quite a lot of them, I've yet to discover one that's actually paid any less than their American (or green-card-holding) counterparts.

Even when employers pay normal wages to H-1B workers, it can still drive down wages by creating more supply. Forcing employers of H-1B works to pay substantially higher wages than normal would indeed by very useful. This would drive up wages, because if employers have to decide between a H-1B with 50% above normal wage or paying an employee from a different company 30% more to make him switch, most would choose to not hire any H-1B.

Comment: Do not rush into conclusions! (Score 5, Interesting) 1037

by tempmpi (#46675221) Attached to: How the Internet Is Taking Away America's Religion

At the moment we are just seeing what is happening when a formally almost monopolistic marketplace is opened up: The former monopolist loses market share and the competition gains market share. But this does not mean the former monopolist is going to disappear, it will just shrink a lot. And while Christianity has decreasing market share in the US and Western Europe, in other place with a former monopoly of state mandated Atheism, Christianity and other religions are gaining market share. E.g.: In China and Russia.

Comment: Re:Wait... wha? (Score 1) 1482

by tempmpi (#46637335) Attached to: OKCupid Warns Off Mozilla Firefox Users Over Gay Rights

I don't see why you should deny someone a legal right based on some accident of biology, whether chromosome or pigment

So mentally ill persons should have access to guns, because it is just some accident of biology that caused their mental illness?

Oh, that argument. So really, even heterosexual couples should have to prove their fertility before marriage. No marriage for post-menopausal women. Would you also annul heterosexual marriages if they fail to produce children within some allocated timeframe?

Would be fine with me. But you are missing an important concept here. It is perfectly normal that laws are made for the average case. It can usually be accepted that a few persons get an unfair advantage or disadvantage from a law that they do not really deserve, what matters is if most people addressed by the law will be treated fairly.
If you say marriage is only for couple who will procreate then you are treating most people fair if you ban gay marriage. You will provide an unfair advantage to unfertile or unwilling heterosexual couples and an unfair disadvantage to homosexual couples who will procreate using donor sperm or a surrogate mother. But you will still treat most people fair as long as most heterosexual couples actually procreate and most homosexual couples do not.

Comment: Re:Wait... wha? (Score 1) 1482

by tempmpi (#46634405) Attached to: OKCupid Warns Off Mozilla Firefox Users Over Gay Rights

. Under the U.S. Constitution, states must grant equal protection of law to all citizens.


That implies making civil marriage available to same-sex couples.

No. The first question is: Is it a discrimination of a citizen or of a couple? Even with gay marriage banned, all citizen still keep the same right to marry a opposite sex spouse.

But the more important thing is: equal protection does not apply when there is rational reason for the discrimination, e.g.: banning some mentally ill people from gun ownership has a rational reason and thus can not be considered a violation of the equal protection of law of mentally ill citizens.

This is a non-discriminatory practice, despite the fact that a lot of gun violence is committed by mentally healthy citizens and a lot of mentally ill citizens would not commit gun violence, even if they would be allowed to own a gun.

Most opponents of gay marriage argue that differences in procreation are the rational reason why same-sex relationships can be treated differently than opposite-sex relationships. And it is certainly true that the likelyhood of procreation differs a lot between these two groups.

When a person can't do something because of the shape of their genitals or the pretense or absence of a Y chromosome, ipso facto that's not equal treatment.

Or just biology. I'm pretty sure I can never get pregnant. I think it might be related to the shape of my genitals. I should sue the state.

Comment: Re:Im all for human rights... (Score 4, Insightful) 1482

by tempmpi (#46633595) Attached to: OKCupid Warns Off Mozilla Firefox Users Over Gay Rights

You can, but others can voice their objection, like OKCupid does here. Freedom of speech is for all, and does not mean freedom from criticism.

And other can voice their objection on the objection. And in this case there are several good reasons to object to OKCupid's objection even if you completely disagree with Eich:

1. Pragmatism: Living together in a democracy requires people to work together even if they have strong disagreements in their religious or political beliefs. For this reason objections should primarily be aimed directly at the belief itself and not at the persons holding them. This enables working together even with disagreements.

2. Fairness: Even if you disagree with someone you should still not misrepresent his stance. OKCupid claims gay relationships would illegal if Mr. Eich got his way on gay marriage. But Gay relationships would still be legal, even when gay marriage are banned. So you can not claim Eich wants gay relationships to be illegal, just because he supported California's Prop 8.

3. Proportionality: Brendan Eich donated $1000 for Prop 8. A rather small sum of money for a high profile engineer such as Eich. This clearly not the most important topic for Eich. He is not a major spokesperson against gay marriage, he is best known for his Javascript work and not for his opposition to gay marriage. The response should have a reasonable proportion to the thing that is being criticized. Brendan Eich's $1000 are now 100x more visible than the $1,000,000 by Alan Ashton.

Comment: Re:what about muslims? (Score 1) 220

by tempmpi (#46543731) Attached to: How Did Bill Nye Become the Science Guy?

You don't seem to understand the meaning of implication. If A implies B, then B must be true in all cases where A is true.

So if a lack of intelligence would imply believe in God then everyone who lacks intelligence would also have believe in God. So even a single person lacking intelligence without believing in a god shows that the implication does not exist.

You seem to understand "implication" as "contributory cause". They are not the same thing. A contributory cause makes something more likely. While a sufficient cause or a implication must ALWAYS have a specific effect.

Comment: Re:what about muslims? (Score 2) 220

by tempmpi (#46542497) Attached to: How Did Bill Nye Become the Science Guy?

Causility != Implication

1) Smoking causes lung cancer, but not everyone who smokes gets lung cancer. If smoking would imply lung cancer every smoker would also be suffering from lung cancer. It is clear that religion does not imply a low IQ, because some really smart religious people do exist.
2) Lack of intelligence also does not imply believe in God, because there are stupid atheists as well.
3) There are many possible causes for both religion and low intelligence.

- If religion is one of the rare sources of hope in insecure situations, how would that make religions look bad? This would be like saying: Antibiotics are bad, they are consumed mostly by unhealthy people.

There can also be causality chains. E.g.:
- Higher Intelligence causes people to question the believes for neighbors.
- This makes it more likely to get a different set of believes than the neighbors.
- If the majority of the neighbors believes in god, mostly high IQ people will not share this believe.

If you look at Lynn and Nyborg's data you will notice that not that nations with the overall highest level of atheist have the highest average IQ, but instead the nations with around 10-20% atheists have the highest IQ.

"Confound these ancestors.... They've stolen our best ideas!" - Ben Jonson