Add IPX8 to the high specs.

With a ~150watt GPU, plus the rest of the system, you are going to have quite a time with heat dissipation in any case that is sufficiently waterproof. Even fairly impressive looking passive heatsinks are surprisingly feeble compared to the usual 'few heatpipes, bunch of fins, actual airflow' designs that normal PC hardware uses. Even if you can add enough of them to your computer's case, you still need an excellent thermal path from the CPU and GPU to the case(for reference, Zalman released a somewhat ridiculous case for this purpose a number of years back. As you can see from the photos, the design requires a pretty substantial number of custom heatpipes for the CPU and GPU to be in meaningful thermal contact with the big passive cooler side panels, while a custom PSU had to be used to keep that part cool. It also cost $1,500)

You may also run into trouble, even if CPU and GPU are OK; with high internal air temperatures: most PC gear has a variety of other heat sources(basically anything with electricity involved, VRMs, motherboard chipsets, RAM, etc.) that are typically ignored for water cooling purposes; but which depend on a modest flow of reasonably cool air to stay within their limits. A fanless PC with decent convection might be OK; but a sealed box isn't going to cut it.

If you can get away with it, your best bet would likely be breaking the problem into two parts: the sealed computer case, with waterblocks on the CPU and GPU, and a radiator with fan for cooling the air sealed in the case and keeping it moving for the benefit of lesser components; and the radiator module, which pumps coolant back into the computer case and cools the heated coolant coming out.

This should allow you to fully seal the computer side of things(with the exception of the necessary data and power connections, for which IP-rated connections are available, and the input and output hose fitting) without it cooking and dying; and leaves only the radiator, pump, and possibly a fan outside the sealed case in the radiator module. Given the demands of vehicle engine cooling and the common need for fully submersible pumps, both are available in very waterproof versions, and the heat dissipation of the radiator should actually improve if it's being sprayed down.

If cold is a concern, you'll of course need to use antifreeze in the coolant, and a temperature sensor in the computer module that either activates an internal heater, reduces coolant flow rate, or both, to allow the computer module to remain at a safe temperature.

LOL; yeah, I noticed that my markup had been filtered after I posted it.

You're being disingenuous, or intentionally obtuse. You putting up your own web page so people can see your rants is a far cry from some putative distributed Facebook competitor that exists only to get out from under the "heel" of what the OP dislikes as properties of Facebook he wants to make as architecturally difficult as possible to implement.

No, that's a feature of snapchat in particular which is considered by most people to be a means of evading law enforcement, at worst, and the same thing as having an expiration date where the service effectively has a sliding "we're going out of business, sorry" at best. Think MySpace.

Ephemeral is a feature to only a very few.

That more of a consequence of the inability of the journalists to classify it, and so they pick a lexicographically "a cherry is like a tomato, because both are red and fruit" close thing, and call it that. IT also sells itself as that, because if you can sell yourself as that, you can pretty much get VC funding.

I think I pretty much want to out Bob as a Nazi everywhere. I want to punish him for being a Nazi by ensuring he is socially ostracized to the point that he gives up being a Nazi because he's decided that his perceived costs outweigh his perceived benefit. It'd also be nice if he can't pass on his heinous meme to another unsuspecting person by being sly about slowly indoctrinating them, and it'd be nice if any woman who might get into a relationship with him and have his kids would be able to make that decision on the basis of complete information. People frequently make an emotional or financial investment in a bad venture, and then rather than cut their losses, they "throw good money after bad".

This is how gambling addiction works. It why people stay in abusive relationships.

You are either an old anarchist, or you are otherwise not very knowledgable about how younger people view "friends" on Facebook. Calling them "friends" is a terminology Facebook uses; these are not "friends" in terms of "web of trust". This is not like a PGP key-signing party.

Younger users accept *all* friend requests. If it turns out they don't like what the person is saying or doing, they "unfriend" them later. But the default is to accept *all* requests. This is not how older people do it, and it's not how you would expect them to treat an online relationship, but it's how it works.

http://www.pewresearch.org/fac...

I think you haven't been following the whole GamerGate sock puppet situation very closely. Yes, it's the equivalent of real-world stalking, and there's no mechanism to deal with trolls now. In a distributed social network, you could be scrupulously upstanding with your immediate peer nodes, and be a total asshole otherwise. Once you are inside the web of trust, you're inside, and even if someone wants to not hear from you, as a peer node, your node doesn't have to run unadulterated software; it can imply graph relationships that don't exist outside their rogue node.

This is, in fact, precisely how the TOR network had been infiltrated by various third parties: peer-of-peer implied trust relationships.

I don't think this is a workable concept, unless you can figure out a way to (1) Stop the whole GamerGate thing in its traces, without hugely invasive surveillance to root out bad actors at their houses, and figure a way to cut out the cancers permanently and/or take criminal and/or civil action to force them to not be bad actors ("Bob is a Nazi; let's put social pressure on him to change that"/"Bob is a criminal; lets put social pressure on him to not act that way by locking him in a cell"), and (2) Figure out a way to do source verification so that if ted trusts Bob, and Alice trusts Ted, that Alice can legitimately not trust Bob without having to throw away the trust relationship with Ted.

I expect all of the number crunching is being done by an on-board AI trying to figure out how the heck to get away from the high pressure water jet...

File it under "stuff that matters".

A lot of arguments for open source are based on things which people outside the project could in principle accomplish, but in practice seldom do. So it's reassuring at least that an experienced developer can build the two most popular browsers from scratch. It means the arguments aren't hollow. I've seen closed source projects that were purchased by companies, only to find out that getting them to build on any computer but the one it was developed on is a serious engineering challenge.

That the process of building these browsers from scratch is somewhat arcane will come as no surprise to any experienced developer. But that it's not so arcane that it's impractical to figure out is good news.

Depending on the technology in question, it may not even be apparent to the special person(without domain specific knowledge that they may lack, or which may not even exist yet).

With something like an Oculus-style VR headset, the "Well, if we can put a screen in front of each eye and track acceleration and orientation, ideally with a fallback for recalibration when the drift from dead-reckoning with inertial sensors starts to creep in" concept is not particularly new. Relatively lousy versions even became just cheap enough to appear in modest quantities in video game arcades, and more expensive ones usually lurk around some academic and R&D operations.

However, unless they happened to have their finger on the pulse of the MEMs business, even an enthusiast of the technology would likely be inclined to dismiss it as a niche application at best(in largely the same way that, even among people who thought computers were pretty awesome and/or profited from selling them, it was hard to be too optimistic about their future ubiquity until transistorization and VLSI: even if the theoretical utility of building machines that do binary math was visible, there ain't no Moore's law for relays and vacuum tubes...)

As I understand it, the DK2 hardware interacts with the host computer at three points: there's an HDMI video in, which feeds the two screens(presented as a 1920x1080 monitor; but physically split into two 960x1080 panels), a USB interface for the in-device sensors and housekeeping purposes(accelerrometer, magnetometer, gyroscope, firmware updates, latency testing device), and a USB connected IR camera for head-tracking based on the IR LEDs on the head-mounted portion of the device).

How much OS-specific work needs to happen, and how is it distributed?

I'm assuming that the HDMI-in is fairly normal, unless they really broke the EDID/DDC or something(but obviously not going to be very pleasant unless the application drawing to the '1920x1080 monitor' knows that each of my eyes is only getting half of it).

Barring very good reasons(probably involving latency), I'd assume that the camera is just a UVC device; but that actually using it as anything but an expensive webcam requires the OR-specific head-tracking software to have access to it (the meat of which is presumably cross-platform; but DirectShow vs. V4L2 and other interacting-with-the-system stuff won't be).

The headset's USB interface presumably needs a specific driver, since 'read the outputs of a bunch of sensors and also firmware update' isn't exactly a USB Device Class; but would presumably be a comparatively lightweight 'wrap the sensor outputs and get them to the host as quickly as possible' thing, with the bulk of the motion and position tracking logic being mostly OS independent except for the layers it has to interact with to get headset and camera data.

Is this largely the extent of it (2 mostly standard interface, one device specific driver, plus having the motion and position tracking software running on Linux and interacting with the OS-specific interfaces to the drivers)? Do I fundamentally misunderstand how work is broken up within the Oculus system? Do I basically understand it; but it turns out that latency demands are so stringent that a variety of brutal modifications to the typical OS graphics system and GPU drivers are also required?

Would you be able to compensate for poor linearity with a hybrid approach involving a silicon detector and a layer of one of the formulations used in scintillation counters?

I'm thinking by analogy to the approach for making 'white' LEDs: the output of the LED alone is atrociously unsuitable, so you add a phosphor blob that absorbs some of the output and emits at enough other energy levels to fill in something resembling actual white light.

Would a silicon detector, with a layer of scintillation material chosen for good performance in areas that the silicon doesn't cover applied on top, potentially provide a more adequate result?

Is it unreasonable for the average height of a population to grow by 7" in twenty generations? I should think so. But if you changed your initial conditions somewhat, maybe less unreasonable.

There are roughly 400 genes known to influence height. Imagine we have a small, isolated population that does not interbreed with other populations -- say on an isolated island. This population's average male height is, say 175 cm for men -- roughly the same as the average American. However the population contains all the alleles neede to generate individuals approacing 7' in height. We then take our population and put them under evolutionary pressure; let's say we shoot everyone who reaches the age of 16 and is below average height. It wouldn't many generations for that population's average height to become quite tall, as "tall genes" begin to predominate.

Let's change that initial condition by stipulating that there are no "tall genes" in the initial population. It's still average height, but maybe it lacks both "tall genes" and "short genes". It would be surprising if the genetic height potential for a newborn changed very quickly, because you've got to wait for a lot of "lucky" mutations and twenty generations is not that long.

Let's go back to our successful initial conditions and change something else. This time the population has all the necessary alleles to produce super-tall people, but it interbreeds extensively with a large external population which is not subject to our culling protocol. Under these conditions the population's height increase will be slow, or non-existent depending on the rate at which individuals interbreed with populations not under pressure.

The bottom line: it depends.