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Comment Re:Cost of access is key. (Score 1) 314

"Number of people times the years they stay equals the amount of food you need. Etc. p.p."

The amount of calories is probably well established, 2200 KCal/day per person give or take. But how do you design a fully self-contained environment which can provided the needed calories to support a (hopefully) growing population? How much would you need in terms of materials and energy to make such a system work?

Comment Re:Cost of access is key. (Score 2) 314

In other words, you can't cheat gravity or the laws of thermodynamics. No one seems to listen, but my initial assessment is that the shear amount of energy required to launch a viable space colony is going to be prohibitive. I have never seen a detailed mass and energy budget for a colony. When exploring the New World you know how far to go, how many supplies to take with you, you had tools you could use to extract resources to support a colony etc. And even then colonies failed.

Thought experiment:
What is required to set up a viable colony? How many tons of food? How much equipment is required to build shelters? How much equipment must be sent up to extract needed resources? How many people must be sent up to have a viable gene pool? How much throw weight is required? How much energy? What is the overall costs in terms of global GDP?

We have a lot of people here, let's sketch some of this out. Simplifying assumption, that booster efficiency will increase by 25%.

Go ahead, give it a shot.. But in my case my gut tells me it will be huge.

Comment Re:Crowd Funded = Scam Artist (Score 2) 211

Read "The Road to Wellville". It is set during the great breakfast cereal and processed food boom in the 1890's. A pattern followed by the great railroad buildout, the automobile boom of the late 1800s to early 1900's, the tech boom ofthe 50's, 70's, 80's, 90's, and later. The oil boom, cattle boom, etc. Nothing ever changes.

Comment Re:Estimation of distribution algorithm (Score 1) 48

I'm curious about the claim "any complex model". Really? ANY complex model?[1] Is this the silver bullet? The Holy Grail? After testing it on two "complex" (definition please) models?

So yeah, I was curious and it looks like they are doing sparse parameter estimation of sorts. I wonder how they deal with non-uniqueness and convergence on local maxima.

What is just as import is knowing parameter sensitivity. If a parameter does not add much to the accuracy of the model, throw it out. This has it's own pitfalls and is why modeling is a black art.

I'll have to dig deeper into it but this is my first impression.

[1] I had a Prof. with a PhD from MIT. It was his favorite phrase "we can model any situation using equation ". Of course this was after making assumptions which resulted in the problem becoming linear with deterministic behavior and a unique solution. I wasn't impressed.

Comment Re:This is bullshit (Score 1) 145

No if you do not discuss and focus on the root causes it will never change. You will have more and more reactionary forces crawl out of the woodwork which will make matters worse. That is another goal of terrorism, to make their opponents look worse than the terrorist are. Mao said it in his "Little Read Book", and it worked.

"For the love of phlegm...a stupid wall of death rays. How tacky can ya get?" - Post Brothers comics