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Comment Re:Great, now what about phosphorous? (Score 4, Interesting) 187

I remember reading "Life's Bottleneck" by Issac Asimov. He calculates that if life expands and uses the elements in the entire crust of the earth, the phosphorus will be exhausted first, before carbon, nitrogen, or even trace elements like iodine and selenium. Phosphorus is life's bottleneck.

But there is a big difference between fertilizing with phosphorus and nitrogen. You only need to add phosphorus once, and then only enough annually to replace what is taken out with the crop, which is usually not much. It is a permanent addition to the soil. But the nitrogen is consumed and returned to the atmosphere as the plants grow and then decay. You need to replenish it every year, either with fertilizer or legumes.

Comment Re:Who is better then? (Score 1) 158

What conditions exactly would be illegal in the USA?

In the USA, it is illegal for a 16 year old to work in a factory that uses "industrial equipment". A 16 year old can work in an office, or a fast food joint, but they cannot operate a fork lift or an assembly robot. If the 16 year old is just assembling an iPad with normal hand tools, or even safe power tools like an electric screw driver, that would probably be okay in the USA. The only exception to underage workers operating dangerous equipment is farm labor, which is exempted from many safely rules.

Comment Re:Are you sure it was China? (Score 1) 158

This is an insanity that we consumers can ultimately defeat by refusing to buy products made exploiting the workers.
Maybe it's time for our " ethical dollar " to speak .

Maybe you should examine your ethics a little more closely. If you make no distinction between companies that don't care, and companies like Apple that are making an effort to improve, then you are not helping the situation. A blanket refusal to buy Chinese electronics means the factory workers go back to the rice paddy. Working long hours for low pay in a crowded and noisy factory is still a lot better than getting paid a lot less for 16 hour days stooped over in a mosquito infested rice paddy with water buffalo shit up to your knees. For most of these people, that is the alternative.

Comment Re: That's not news (Score 2) 393

I'm suspicious of the validity of these studies if their metric was standardized testing

Standardized tests don't measure everything. But if a kid does poorly on a standardized math test, that most likely means the kid didn't learn math. If a student can't read a paragraph and answer questions about it, it most likely means the student can't read well. Reducing class sizes is expensive, more so than almost any other educational intervention. It is not acceptable to assume that it "just works" in the absence of evidence.

Educational reform has a long history of "faddism", where changes are made in the absence of evidence. "New math" and "Whole Word Learning" were inflicted on millions of kids before their folly was realized. But in those cases we could fix the problem by just replacing the textbooks. Smaller classrooms often involve structural changes to the school. That will be much harder to fix if it turns out to be yet another mistake.

Also, how do you conclude that there's no benefit, and then go on to explain the real reason for those nonexistent benefits?

Nobody said it doesn't work. Just that it doesn't work well enough or broadly enough to justify the cost. What we should be doing is identifying the situations, and the particular children that most benefit. This appears to be young (K-3) children with disadvantaged backgrounds. Currently this is the opposite of what we do. Small classrooms are mostly commonly used in high-income areas with brighter kids that get little benefit.

Comment Re:Dear God (Score 1) 124

(Actually, Jeffrey Skilling is a counterexample)

Skilling was a fool. Against his lawyer's advice, he went in front of a congressional panel, the representatives of the people, and answered their questions in plain English. He paid a heavy price for that, which will serve as a valuable lesson for anyone else that thinks that honesty is rewarded in our society.

Comment Re:That's not news (Score 4, Insightful) 393

Class size has one of the largest impacts on quality of education.

Actually, no. There is a wide spread belief that class size improves education, but there is shockingly little evidence to support that belief. The biggest controlled study was the STAR Study done in Tennessee during the 1980s. It found the benefits to be minimal and uneven. Other studies have generally found even less benefit. Kids in early grades benefit most, with little to no benefit from smaller classes beyond grade 3. Most of the improvement goes to the underperformers. In some cases, the smarter kids actually do worse with small classes. This may be because they are forced to follow along with the class instead of reading ahead or learning on their own.

Much of the benefit from "smaller classes" may actually be from "quieter classes". Many young children have difficulty filtering out distracting noise. Good sound proofing, and reduction in disruptive behavior, can often bring as much benefit as smaller classes. Interesting, improving student/teacher ratios by adding teaching assistants has been found to provide no benefit.

If correctly targeted, smaller classes have their place, but they are far from a panacea.

Comment Re:japan is a fascist nation that was spared (Score 0) 159

All it takes is one coup for the Pontipines to invade Wottingerland.

The solution to that problem is collective defense. An agreement like NATO's article five "An attack against one is an attack against all", means that the one country that seeks war must be stronger than all the countries that seek peace.

Comment Re:Why yes, I would. (Score 5, Insightful) 209

And the exact same thing could happen to any other completely mechanical device.

You design the mechanism so that it is physically impossible for the software to do something dangerous. In the case of Therac-25, there should have been a mechanical interlock that cut power to the radiator when the shield was not in place. In the case of the needle sticking robot, you use an actuator with a stroke of, say, 5mm. Then there there is no way it could "jab through your arm". You also use a weak actuator, that doesn't have enough physical strength to push into bone, even when given full power. You put a spring-loaded (not software controlled) sheath over the needle, so the needle is never exposed unless it is pressed against skin. You design the hardware assuming the software is malicious. You design away any way you can think of for the software to do harm.

Then you design the software assuming the all the mechanical interlocks have failed, and use sensors to double check everything.

Comment Re:Why yes, I would. (Score 5, Informative) 209

Therac-25 is an example of the dangers of improperly tested computers with lethal equipment.

The Therac-25 was the result of layer after layer of utter incompetence. They assigned a programmer who wasn't qualified to write a javascript button-click handler, to write life-critical sofware. Then no one else even looked at his code. There was no design review, no QA or bug tracking, and very little testing. Even after the defect was reported, there was no review or followup, or realization that it could even be a software problem. But the problem went much deeper. The hardware design was just as defective. There were no interlocks, in either hardware or firmware, to prevent defective software from killing patients. Many books on mission critical embedded system design devote an entire chapter to all the stupid mistakes that made up the Therac-25. If you make a list of the rules of sane system design, the Therac-25 design will have violated nearly every one of them.

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