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User Journal

Journal Journal: Race is a social construct, again. 2

I thought it was already pretty well understood that "Celtic" is only meaningful as a linguistic grouping, but it seems the old idea of a separate "Celtic race" or "Irish race" is pretty strongly embedded, even now:

DNA shows Irish people have more complex origins than previously thought

This makes me think about wider issues. I don't know how many online discussions I've been in recently in which I've been solemnly assured that humanity is divided into three races. (Three shall be the number thou shalt count, and the number of the counting shall be three. Four shalt thou not count, neither count thou two, excepting that thou then proceed to three. Five is right out.) And people will go on believing this, even when genetic evidence makes it perfectly plain that there's no such thing as race, never has been and never will be. There are heritable phenotypes, some of which are clustered together as a result of geographical or historical accident, none of which are set in stone and almost all of which are continuous rather than discrete states. The weight we assign them is entirely cultural.

As always, Darwin puts it elegantly: "Man has been studied more carefully than any other animal, and yet there is the greatest possible diversity amongst capable judges whether he should be classed as a single species or race, or as two (Virey), as three (Jacquinot), as four (Kant), five (Blumenbach), six (Buffon), seven (Hunter), eight (Agassiz), eleven (Pickering), fifteen (Bory St. Vincent), sixteen (Desmoulins), twenty-two (Morton), sixty (Crawfurd), or as sixty-three, according to Burke. This diversity of judgment does not prove that the races ought not to be ranked as species, but it shews that they graduate into each other, and that it is hardly possible to discover clear distinctive characters between them."

User Journal

Journal Journal: Review: SinkPAD Direct Thermal Pathway PCB 1

I've spent the last month testing and demolishing a bunch of new-design thermal PCBs from SinkPAD, and have come to the conclusion that this is a solid solution versus traditional dielectric PCBs commonly used for mounting LEDs. There are many pros, and a few cons, and I will address these in my review of their product, written below.

We will start with the good stuff first, the Pros. The SinkPAD Direct Thermal Pathway PCB is made from solid aluminum or copper (as of the time of this writing I had yet to test any copper PCB), so it's very good at thermal transfer. This helps make it easy to solder; versus a traditional dielectric board, the solder took to the SinkPAD in roughly half the time. This also comes in handy for reflow work and rework, as mounting and un-mounting an LED from the board is quick thanks to the PCB being constructed out of high-conductivity aluminum and copper. Repairing any mistakes takes minimal time and effort, a must for any prototype designer or hobbyist. The solder resist is also very solid, during my reflow cycling test I never once saw a solder bridge form, nor had any shorts. The same solder resist is quite durable against thermal shock as well. I torched it until it was smoking and crackling, near-black, and with no problems I was able to mount an LED to it and light it right up, and the remainder of the pad transferred heat exactly as it should. This durability is exactly what the military and police forces could use for LED-assisted weapons solutions, such as barrel or grip-mounted lights, or IR night-vision equipment. The aluminum boards are light-weight and stiff, very difficult to bend, even with a pair of clamps and pliers and my full weight applied.

Now for the cons. Due to how the thermal pathway is manufactured, there's an indentation on the back of the board. This means you need to use more thermal paste/epoxy, and you need to be more careful not to introduce air bubbles and gaps. On the aluminum boards, there is no solder pad on the back side, which would help greatly since solders tend to be more conductive than thermal pastes and adhesives. The copper board likely wouldn't need it, since copper is easy to solder. Speaking of copper, there are a distinct lack of copper options for many of their PCB choices. While this is understandable (many of these LEDs simply don't need it) the ability to have broader choice in materials would be nice. My final bad note is the difference between prototype boards I have versus some of the production boards. An older X-Lamp XR-E board had four screw holes for improved mounting, and they were placed so that most screws that could fit those holes would not have the heads short out on the contact pads. These holes are nonexistent on the star and disc boards. The star have their electrical contact points too close to the indents at the outside to allow screws to be attached there, but the circular boards look like they might have a better chance.

Overall, this is a solid piece of thermal management tech for LEDs. The ease of use and durability should appeal to a wide variety of LED consumers, from hobbyists, designers, and engineers to police, military, and even more groups of people and industries. Most of the cons are personal nitpicks and aren't exactly game-breaking important, and the pros certainly outweigh any con I've been able to notice. Highly recommended.

User Journal

Journal Journal: nosupportlinuxhosting fail

I decided to try out nosupportlinuxhosting but they appear to have suspended hyperlogos.org without notice or explanation. I sure hope I don't have to issue a chargeback, that would be stupid. I'm already waiting for Amazon to process two returns that have been sitting around at their facilities for weeks.

User Journal

Journal Journal: Because I clearly need to do this more often

Dear Internet:

Some aspects of your style of argumentation have recently caused me some concern, and I thought it would be best to address them now, before they get out of hand.

If I insult you, I am not necessarily using an "ad hominem" argument. This phrase (literally, "to the man") refers to a specific logical fallacy, that of assuming that when someone you dislike or consider beneath you makes an argument, it follows that the argument is wrong. "You're a moron, so I don't have to listen to anything you say" is an example. "Only a complete idiot would say what you just said, so you must be only slightly smarter than the average flatworm" is not.

In fact, it's probably best to stay away from Philosophy 101 lists of common logical fallacies all together. Just as not all insults are ad hominems, not all citations of experts are "arguments from authority." Not all "slippery slope" scenarios are fallacious. And for the sake of all you hold holy, if you don't understand in gory mathematical detail what correlation and causality actually mean, and the different uses of the verb "to imply" in different contexts, please stay away from any version of A Maxim I Will Not Utter Here, But Which You Can Probably Guess.

All that being said, there is one fallacy to which you fall prey on an alarmingly regular basis. If you disagree with what I say, you have the right--in some cases, the duty--to voice your disagreement. Free speech is a wonderful thing, and it is easier to exercise in the modern world than it has ever been before. By all means, speak up.

However, please make sure that when you're voicing your disagreement, you are disagreeing with what I said. Replying instead to what someone else said, or what you think I'm "actually" saying, or what you think I or someone else might say in the future, are examples of the "straw man" fallacy, and although I have not performed the analysis necessary to test this hypothesis, I strongly suspect that this poor overworked scarecrow is to be found in greater numbers in online discussions than any other type of fallacy ... which, now that I think about it, is a pretty impressive accomplishment.

Thanks for your attention to these matters. Hopefully now that I've explained the error of your ways, we can move on from here and enjoy friendly, well-reasoned discourse on a wide variety of topics.

Sincerely,
That Guy Who's Always Right On The Internet

User Journal

Journal Journal: SinkPAD & CREE, Together At Last!

I finally got the right boards personally delivered to me. It was quite funny, exchanging tiny baggies of what any person at least ten feet away would assume were drugs right in the middle of a Del Taco parking lot. Then watching an accident happen not fifteen feet from us, between bicyclist and car.

Anyways, I just shot a little run of the MK-R, both of them, driven at 18w each. Note how they obliterate the Cree XR-E to the left, driven at 1.2-1.3w or so (3.7V rated Vf @ 350mA.)

I'm going to go step outside to get a night shot. Updates later in this journal post, in the comments.

User Journal

Journal Journal: Night Test of the MK-R 2

Finally got around to doing a night test of the MK-R.

I went out onto my patio, and put it right beside my 100w incan that typically lights the porch.

And here's the result. As you can see, absolutely no contest. Fluoro equivalent to 100w incan is a ~26w bulb, so we're looking at around 25% the power consumption of an equivalent CFL (LED driven at 6w) and way, way more light.

Still unable to drive full power. SinkPad mistakenly sent me XM-L boards, not MK-R.

User Journal

Journal Journal: This website has gone to shit 1

I'm not talking about the content, that has always been shit
I'm talking about what happens when I try to modify my relationships.

OK

The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator, admin@slashdot.org and inform them of the time the error occurred, and anything you might have done that may have caused the error.

More information about this error may be available in the server error log.
Apache/2.2.3 (CentOS) Server at slashdot.org Port 80

Of course I reported the error. Of course I never heard back. Now I'm seeing it again.
Slashdot is basically unusable without friends/foes lists.

User Journal

Journal Journal: Checking Out The New Cree MK-R LED 9

I managed to get some engineering samples of the Cree MKR LED announced on /. a couple weeks or so back.

Needless to say, I was thoroughly impressed. I ran 12V @ 200mA, 500mA, and 1250mA. You know how us geeks/nerds say do not look into laser with remaining eye? You don't HAVE any eyes left with the new MK-R, even at a measly 200mA of direct current at 12V. At 1250 mA, I only needed half a second before the diode packaging began to melt the green PCB, the heatsink was absolutely ineffective. Be prepared to use metal SMD-mount boards for these diodes, because that cheap green board used for most SMD LEDs simply will not cut it. Pushing 15w in a 7mm x 7mm package, you need serious heat dissipation capabilities. Also, DO NOT HOLD THE DIODE WHEN DRIVING AT 200mA! You will blister yourself.

I no longer have my light meter, as I would use that to check flux levels and lumen levels, but needless to say, you drop a quad of very-efficient nearly 4-watt diodes into a single tight array like this, and the world is going to light up before your eyes. I would love to see one of these in a Mag-Lite. At 200mA, 500mA, and 1250mA, you would have all the light you need. Remember that commercial where the kids with the flashlight are using new Energizer batteries and it looks like they're suddenly using a 1,000,000 candlepower light? It's even better than that.

Just one of these would light up my entire 15' x 24' living room, quite possibly more, with wonderful light levels. I could see this sitting in the center of my ceiling. Two bedrooms, two bathrooms, living room, kitchen, dining room. Seven rooms, 105w operating power with all in operation. I could leave my whole home lit up for the same cost of a single 100w incandescent light bulb, which barely lights one room. Oh wait, I forgot the porch and patio. Make that 135w operating power. And in reality, even at 500mA drive current, I think that's more than enough light for an area roughly 25' x 25'. Still beating the pants off of equivalent incandescent or fluorescent. It's the end of them, and I already have the belief that these will truly smash HID systems.

I want single-color versions of these. Cree, if you're reading/listening, you have technology in your hands right now to take over an entire segment of the optoelectronic market. You dropped out of said market (and a couple of others) when you quit making 660nm diodes, and you could really take this class of diode to great heights if you could specialize single-wavelength versions of this.

User Journal

Journal Journal: Users opt in, but they don't opt out

Google will tell you that their collection of "anonymous" location statistics is opt-in. That is, technically, true. However, on Gingerbread it is not opt-out. Once turned on, there is no option to disable it, that was added later. That, or I have forgotten all I once knew about google-fu. I can find how to change your mind about this on ICS, but not on GB.

The Military

Journal Journal: It's a bug hunt.

I've said before that the expectations my generation of GIs had when we raised our right hands were shaped by two main forces: the flood of Vietnam movies that came out when we were in high school, and Aliens.* Given that the people who are now running things at the Pentagon went in about the same time I did (!) I can't help but think that the latter had a lot to do with the fairly smooth acceptance of women into combat positions over the last few years.

So it's just bizarre to me that a quarter of a century later, with a solid history of women fighting in Iraq and Afghanistan, this kind of thing is still happening. And because video games will probably have just as much to do with shaping the current generation of recruits as movies did with previous generations, it's going to be a problem on the battlefield as well as the web.

*Whether it's a good thing or not that recruits report to basic training with their expectations shaped by popular entertainment is a separate issue. Just accept that they do.

FEAR OF A WOMAN WARRIOR -- The development of Aliens: Colonial Marines and comments from Epic Games' art director reveal a troubling attitude about strong women in games among some major developers.

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