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Comment Re:2 time the gravity thought (Score 4, Insightful) 134

"Note this world is rather denser than Earth - 5x the mass packed into 4x the volume. Should be a great place for heavy metal poisoning. Or toxic wastelands. Something like that...."

Not necessarily. A planet with a larger radius retains heat better thanks to its lower surface area to volume ratio, and a planet with higher gravity will more efficiently separate its component materials by density, i.e. drawing metal elements into its core. And since the planet is retaining more heat, it will probably have had more resurfacing and tectonic activity than Earth did. So a denser planet does have more metals, but by being larger it is also going to have a lower proportion of it [metals present during formation] in its crust than a 1G planet.

As to which effect dominates in this situation, that's a question for someone with an actual model of planetary evolution.

Comment Re:facebook changed. And grew. (Score 2) 452

Facebook has a much greater degree of lock-in though. Aggregation platforms have no unique content, so they're much more vulnerable to exoduses (exodi?). Not even reddit's communities really count, since by their own numbers their traffic is ~75% accountless and ~95% non-commenting. If reddit wants to morph into something its users oppose, it had better do it very, very gradually.

Comment Re:North Pole (Score 1) 496

Nope. Those "inner rings" wouldn't allow you to walk south for one mile, so they are invalid.

This is false. The rings in question are north of the south pole, and you start out exactly one mile north of them, not on them. Your starting point is always one mile plus [some distance] from the pole, such that after the first one mile trek toward the pole, you are standing on the ring without having crossed the pole. See this mspaint illustration (which ignores scale with reckless abandon). The bullseye is the pole, and the straight segment is always walked first to get onto the 1/n-mile-circumference ring, which is walked n times, and then the straight segment is walked back north.

There are an infinite number of starting latitudes around the south pole corresponding to any integer value of n, and obviously every longitude is valid.

Comment Fresh from Rupert Murdoch's press (Score 2) 556

Frankly it's more surprising that a respectable publication, even a right-leaning one like the Wall Street Journal would think it's a good idea to wade into the religion/science "debate" even in its opinion section. Of course it is irresponsible for a newspaper to not publish articulate expert-authored responses to an opinion piece, newspapers have a responsibility to publish responses written by more-famous and more-qualified persons when the response meets the paper's basic standards. But the WSJ is owned by Rupert Murdoch so I can't say this is a particularly surprising lapse of journalism. (This is hardly first time their editorials have been accused of deliberate bias imposed by the paper, over and above the author's opinion)

In defense of the WSJ, they do seem to keep their bias to the opinions section, which is the appropriate place for it after all.

More interesting will be seeing what the long term effects of Murdoch's influence does to the paper's reputation; in the extreme case it may turn out like Fox News (also owned by Murdoch) and become a punch line to anyone who isn't among their readership. Though I think it's more likely they will successfully navigate the slippery slope, and maintain their position despite having these minor scandals every year or so.

It's a bit depressing, since the editorial in TFA and all their climate nonsense are counterfactual in the fairly literal sense of ignoring and misapplying science and logic in a way that could nominally support any conclusion whatsoever. A newspaper of the WSJ's former caliber should and surely does know better, but such is the state of the american press in 2015.

Comment Re:Plant Recognition (Score 1) 421

I imagine this sort of identification software would just output a list of possible identifications ordered by probability. I think the shortcomings you've identified could be mitigated by making the user go through a decision tree answering illustrated questions about the plant's size, leaf branching, seeds/berries, etc. and by comparing the user's GPS location to plants' known distributions. If the list linked to descriptions and pictures of the potential IDs it'd become a pretty useful tool even if its single best guess wasn't reliable.

This sort of app runs into the issue of needing a large-ish database of plant pictures and data descriptions, but field use usually precludes offloading the computation to a big computer somewhere. My audubon society birding app has a 650MB library of ranges, calls, and pictures, and it doesn't even attempt to make those machine-searchable in any way. And there are a lot more species of plants in north america than there are birds.

You're dead on about grasses and fungi, too. A lot of those identifications rely on color, sheen, and texture, none of which can be measured by a camera in natural lighting. Any plant ID app would be strictly limited to leafy plants.

Comment Re:What about Air Conditioning and Power Alerts (Score 1) 327

Well it clearly depends on context. Total system-wide demand is different from the demand at your house. Demand at your house is clearly lowest when you're outside of it, assuming your central heating/cooling is configured normally, regardless when the peak demand at the system level is. Presumably every human is somewhere, and that somewhere is both lit and heated/cooled, but specific locations have different usage profiles depending on their intended use. Indeed the whole [south for overall efficiency] vs [west to align with usage] necessarily cannot have a single answer for all buildings, as it depends not just on (a) the average usage profile of the building in question over time of day, but also (b) the price profile over time of day that the utility charges you, (c) the production profile of your solar panels over the relevant range of directions, and (d) whether you have storage capacity or, equivalently, the regulatory environment allows you to sell your surplus power onto the grid. With all of these things known, it's more or less straightforward to solve for the angle you should aim your solar panel at. But without knowing these variables per se, it's not remotely possible to make a blanket statement that "solar panels should point west".

The same goes at the system level, to a lesser extent. Superficially it would seem that the system would prefer to have the solar panels producing at their optimum (i.e. south-facing) and make up the difference with coal/nuclear/hydro during peak hours, since this produces the most power overall. But if you get down to the actual details, it's possible that max efficiency solar exceeds system demand at offpeak hours and wastes energy, or that the transfer losses are nontrivial, or that the plant providing the base load can't scale up efficiently or to an absolutely high enough amount at peak hours, and so on. So it's not necessarily the case even that a whole power system is optimal with optimally-oriented solar panels.

So yeah I think TFA's title is pseudo-clickbait since it reduces a complex system down to "everyone is doing it wrong". But it's definitely a lesser tier of clickbait than we usually apply the term to.

Comment How is this surprising? (Score 5, Insightful) 282

I don't know why the researchers were so surprised by this. If the genetic variation already exists within the population under selective pressure, then the "evolution" measured by phenotypical changes in the population can take place literally overnight. Kill every human under 6'4" and the population will be 6'4" from then on, especially if you don't return to the set of selective pressures that had encouraged the shorter average. Sure there will be a lot of shorter individuals being born at first, but they'll fall to the same new selective pressure that killed the initial short cohort. This is exactly how the famous peppered moth evolution event happened so quickly; it wasn't anything unusual about the moth species in question, just a quick change in the suitability of existing genes. Evolution is only slow when the locally optimal genes don't exist in the population, and need to arise by mutation or genetic flow, or when an immediate optimum has room for genetic fine tuning, so to speak. TFA isn't really an example of evolution per se, it's an example of natural selection--a closely related concept in that they almost always co-occur, but it is not the same thing. We've changed the equilibrium frequencies of various genes, but as far as we know there are no new genes in this population. (And as far as that goes, it's a decent illustration of the importance of genetic diversity in a population: this population would be extirpated if it didn't have the genes responsible for these behavior and phenotype changes.)

Comment Re:Midwest (Score 1) 439

Also a midwest bicycle commuter here. It's been pretty lousy dipping into the tens and zeroes, then popping back up long enough to melt everything into a brown pile of soggy goo. That, and central illinois doesn't have the hills for those hour long, slow motion ice pileups that warm my heart to watch.

Comment Re:Common sense says... (Score 1) 417

Then perhaps the rude thing is to stare at other people's houses via street view?

I'm sorry, I don't buy the cultural argument here. If it's in view from the street it is in public view, no amount of cultural values alters that fact. If an entire culture has an issue with too little privacy in their front yards they need to ban things like street view altogether, or start building some fences.

What does this lady expect anyway? That google is going to pay people to look for every little possible thing that could offend a japanese OCD shutin? They already took down the photo when she complained about it, asking more than that from an internet company is asking too much.

Comment Re:False positive (Score 1) 693

This was a midterm for a class of 600 that used a test bank. I imagine It was multiple choice.

Granted there are a couple clever ways to out cheaters on multiple choice exams too. I once had a class where the professor subtly altered about 1 in 3 questions so that students who cheated by glancing at each other's scantron sheets would miss these questions disproportionately by copying the wrong bubble from their neighbor, and used this as evidence for cheating. I only found out about this because the TA was one of my friends.

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