pavelcherepan

I think one other major issue with the current and proposed designs in terms of commercial energy production is that a large part of the energy of the reaction is carried away by neutrons, which makes it hard to collect this energy and transfer into a usable form. This is especially a big issue with D-T fusion reaction.

Mythbusters tested it once, but like most of their experiments it's hard to call it controlled or very scientific for that matter.

By cooling it down in a vacuum. If you look at the phase diagram of water, below 611 Pa liquid phase can not exist any more regardless of the temperature. https://upload.wikimedia.org/wikipedia/commons/0/08/Phase_diagram_of_water.svg

Great post! Thanks for the interesting read!

Thanks heaps! I'll have a look at this, see if it will work.

Pretty much exactly this. More of the practical grade control or rather trying to show colleagues that the way they are doing things is wrong. I intuitively see that it's wrong and I'm capable of doing it better, but I can't figure out what statistical tool can be used on a regular basis to compare.

Not exactly, but similar. And going by your picture I need to separate for example those peaks in the bottom-right corner, but as there can be various ways I can do it, I need to somehow compare whether one is better than the other. I tried to go simple with stdev, but as the data is not entirely random I get lower stdev if I use an entire data set. If I go more than 20-30 points stdev levels off and starts decreasing and goes to its lowest with the entire data being used.

Thanks for the help, although I think I did phrase the discussion title in a wrong way. I'll try to be more clear this time. I have a set of points with spatial location and some grade values. I need to separate the entire data set into an arbitrary number of spatially correlated chunks. Obviously, I can do it in many ways. So what statistical measure I could use for these resulting "chunks" of data to compare the variability of grade between different ways it can be split? I hope this makes more sense.

Hi all! At the moment I'm looking at some huge array of geological data and need to quickly analyse it. What I'm mostly looking at is partitioning the data set into smaller chunks, while ensuring that the particular way this splitting is done would give me chunks of data with lowest variability possible. I have some statistical software in the office, but I'm in the middle of nowhere and won't have access to it before the due date. Any thoughts on what statistical measure I can use? Thanks in advance!

Your thinking is so flawed it almost physically hurts me to read your posts. Going by Wikipedia definition and precise measurements in the paper I linked: Cro-Magnon - not AMH, Idaltu - not AMH. Going by mainstream science consensus: Cro-Magnon - AMH, Idaltu - AMH. We're not in QM forums so you can't have quantum superposition of these two possible states And we're at this stage in the discussion where I have to resort to memes:

Where's your integrity, mate? Idaltu is also considered an AMH by mainstream science, therefore if you decided to create you own classification that goes against what scientists agree upon, don't go bringing mainstream science references to support your losing hand.

Yes, Idaltu probably shouldn't be considered and AMH, but that doesn't magically make C-M an AMH.

No, your "theory" is junk. It contradicts the very definition of what qualifies to be an AMH.

Read my earlier post ^

No. Let's look at the definition again: Since only 88% of the cranial features of C-M fall within ranges common in human populations, it bears a phenotype not common in modern humans and therefore, by the definition, can not be considered an AMH. The phenotype being an expression of genotype means that the genotype of C-M would've been different from genotypes in modern populations. And no, you haven't provided any genetical data, don't fool yourself. It can be considered a very advanced archaic human, potentially the closest to modern humans, but again, by the very definition it's not an AMH. And this one.. Hahahaha! Like, really?! That data is in the paper I linked, it just doesn't show species names and instead names skulls by the locality of their discovery, which is for obvious reasons, because skulls from different localities can represent different time periods and be different even if they're the part of same species. Herto skull is H.S. Idaltu. It has 70% of features similar to H.S.sapiens. Yet again, going by the definition, it's an archaic H.S.

Once again, your metrics are very arbitrary. You can't just say "oh, this one is flattened and that one is not", you need to provide some numbers and proper numerical measurement format. For example here's a table with numerical values for some important cranial features used to id anatomically modern humans. How do these numbers fit into your hypothesis? http://www.pnas.org/content/99/3/1134/T1.expansion.html Taken from this paper: http://www.pnas.org/content/99/3/1134.full P.S. These metrics are arbitrary as well, but at least they have some science basis behind them. P.P.S. Here's another paper with numerical measurements of several hominid skulls including your beloved Cro-Magnon too and comparison to ranges within modern human populations (page 6): http://docs.lib.purdue.edu/cgi/viewcontent.cgi?article=1007&context=jca Surprisingly for you C-M is outside normal modern human range in 3 categories and in most others it's very much on the upper limit.

Basically that ^ I've always been rather skeptical of panspermia. I mean, I agree, it has some valid points and it could happen, but that still doesn't take away the abiogenesis, because life would still have to come from non-life, and if we all agree abiogenesis must have happened somewhere at some point in time, then we just take our handy Occam's razor and start slicing and dicing.

No, really, how can you not understand that both the "planet" and "archaic human" (or just "human" for that matter) are totally artificial terms for objects that have no intrinsic features on a deep physics levels that would help differentiate those from any other type of object. Elementary particles have such deep intrinsic features that define them without the need to invent artificial categorisation, but humans or planets do not. There's no reason why Plato's definition of human as "bipedal animal with no wings" is not perfectly applicable. The only potentially defining characteristic of humans that is potentially possessed only by us is consciousness, but the problem is that science doesn't understand what it really is and can't test whether any other living creatures are conscious. I mean, like, scientists wouldn't be able to even say whether their own colleagues are conscious or not. This is why any classification of humans is by default based on arbitrarily chosen parameters defined by scientific consensus, rather than nature. And since you're so transfixed on the cognitive abilities, can you answer a simple question: human complex cognition, forward thinking, culture etc. was a result of: a) purely biological evolution, b) influenced by technological advances (i.e. increased food supply and resultant increasing group sizes leading to increased specialisation of individuals and to development of complex structures like economics) or was it c) positive feedback between biological evolution and technological advancement (i.e. increasing brain size leading to more complex technology, thereby leading to more complex societies and so forth)? Please choose one of these three and explain why you think it's the correct one.

MigL I think you're referring to Harry Harrison's West of Eden series. Loved those books!

I have already agreed in post #7 that I've failed to address this point in my original post, but I accept that it was my bad and what you and Ophiolite said is correct. That's not exactly true. During Permian age synapsids were the largest terrestrial vertebrates, while diapsids were smaller and less numerous. But then a wild Great Dying appeared. It used Extinction and it was super-effective! And as always during extinction events largest animals are the first to suffer and that resulted in a great reduction of number of synapsid species and those that did survive had to adapt to new conditions. When dust settled (both figuratively and literally) the newly formed ecosystems have been taken over by diapsids, which during Triassic evolved into dinosaurs as we know them today. Hence, the fact that mostly during Jurassic and Cretaceous dinosaurs were dominant land-based animals was not specifically a result of them being "better" than ancestors of mammals, but was a matter of luck (in the form of great dying) and favourable climate that provided plenty of food among other factors. One useful characteristic that allowed them to become successful was of course skull structure, since compared to synapsids, diapsids can grow to a larger size slightly more easily simply because the skull is lighter. But this characteristic would not have made much difference if the other two conditions I've listed above didn't get fulfilled.

Well, not quite as I can understand. Using drag formula was also the first thing that popped into my head as I was starting to read your post, but there are different types of parachutes and they will have different maths associated with them. There is a standard round chute, which seems like this way of solving the problem should work for it, but let's not forget that they have a hole in the middle, otherwise oscillations from escaping air would make it very unstable, so in order to be more precise you should consider the effects of this hole since it will effectively reduce the area of chute and hence you'd need the radius of the chute to be slightly larger than without the hole. Ram air type parachutes on the other hand generate both drag and lift (round chutes have no lift) so the calculation for this type should include both effects. It gets pretty complex for this type. Here are some pages you might want to take a look at: http://www.rocketshoppe.com/info/The_Mathematics_of_Parachutes.pdf https://info.aiaa.org/tac/AASG/ADSTC/RamAir%20Parachute%20Design/Lingard.pdf http://wwwf.imperial.ac.uk/ssherw/spectralhp/papers/PhDThesis/N_FogellPhDThesis.pdf

I wanted to edit that part, but them sort of forgot about it. Love the picture J.C.

The asteroid did make an impact and made things quicker, but the extinction event had started before the Chixhulub event. There was severe volcanism on Indian plate similar to Siberian sills that were involved in the previous extinction event, divergent boundaries at many other plate boundaries. Whole ecosystems were getting destroyed and climate was changing rapidly. Cenozoic also had recurring ice ages throughout, not the conditions where large cold blooded animals could proliferate and be successful. Hence there is a good chance that dinosaurs would've died off regardless, asteroid impact just made it all end faster. So mammals woulve probably still had taken all the land based ecosystems and we'd come to about the same result we see now.

Science news just in: "An international team of scientists led by Pavel Cherepanskiy after thoroughly testing their hypothesis have confirmed that hitting one's head on the wall is more enjoyable than discussing science with EvanF. This breakthrough discovery will eventually lead to a giant leap forward in the field of crackpottery." http://www.why_did_I_even_bother.com