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File 130618073317.gif - (79.64KB , 800x600 , 1305400066996.gif )
1081 No. 1081 hide watch quickreply [Reply] [Edit]
My current Asus EEEPC900 is literally falling apart and loves to overheat, thus, I need a new one.
I don't need it to have a lot a power or disk space, I won't be storing much on it besides the OS and that will be linix. I don't need a webcam, I don't need a CD drive. There are only two things that I will really need:
-Somewhat tough
-long battery life
I don't care if its new, used, or refurbished, and I don't care if its a newer or older model. As long as its relatively cheap I don't care.
So knowing all this, what do you suggest?
>> No. 1082 [Edit]
The cheapest you can get with usable new mobile computers is probably this ARM-based smartbook for $199:
http://www.genesi-usa.com/products/smartbook
Battery life is claimed to be 7 or 8 hours, IIRC.

Other than that, I'd suggest simply getting another EeePC of a newer generation.
>> No. 1083 [Edit]
>>7387
Ohh, that sounds cool, but whats with the 3G thing? Is it like some free deal like with the Kindle? It does not say anything about subscribing to ATNT for service on the site.
3G/GSM would be really good for me because I want to replace my old one for the purpose of traveling.
>> No. 1085 [Edit]
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1085
>>7389
Sorry, I don't know anything more about it apart from what's on the web site, and I didn't even read all of that.

Also notice how it doesn't have any built-in connectors for external displays or wired LAN, might be an issue.
>> No. 1087 [Edit]
Moved thread.

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1088 No. 1088 hide watch quickreply [Reply] [Edit]
Meanwhile, on Earth...

http://science.nasa.gov/science-news/science-at-nasa/2011/04may_epic/
>> No. 1089 [Edit]
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1089
>> No. 1090 [Edit]
well this isnt new they just proved it - the idea of gravity influencing space. That's part of the stuff that happens around black holes...

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1091 No. 1091 hide watch expand quickreply [Reply] [Edit]
Do we have any future IT guys or programmers on /tc/? I've been considering going to school for something in the tech field since computers are some of the only things I'm good with.
5 posts omitted. Click Reply to view.
>> No. 1097 [Edit]
Yes, DeVry, like most for-profit schools, don't offer good education and your money and time is far, far better spent at a good university.
>> No. 1098 [Edit]
Will be attending the Zenos IT Academy starting Feb 28th. My secondary school left me with lots of nice little crappy paper qualifications, but no actual skills.

I'd prefer a career in music (bassist) but it's not stable enough. I could see myself doing a lot worse than IT, so I'm jumping at the chance. I find computing in general fascinating anyway.

>>167

I agree.
>> No. 1099 [Edit]
I don't know if anyone else here is into game programming like I am, but a guy from /v/'s game dev threads has been maintaining a server with resources on the subject. It's at deeserver.wmclan.net if anyone wants it.
>> No. 1100 [Edit]
test

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1002 No. 1002 hide watch expand quickreply [Reply] [Edit]
so is it like possible to create an algorithm to calculate any function using only addition and subtraction.
I tried my hand at that the day and I couldn't find a way to calculate multiplication that didn't involve integers(2.45*3.68 for example) as I couldn't find a way to move a number's decimal place using only addition or subtraction.
what do you guys think
am I missing something here?
3 posts omitted. Click Reply to view.
>> No. 1006 [Edit]
>>270
Multiplication is not repeated addition, at least when it involves non-whole numbers. That's just something that elementary school teachers teach because it's easier for kids to "understand" even though they're not really understanding it on a conceptual basis.

There's a reason why it's one of the 4 elementary mathematical operations. Just go google "multiplication is not repeated addition" and you should get a lot of hits.

So to answer your question, it's impossible.
>> No. 1007 [Edit]
>>274
>There's a reason why it's one of the 4 elementary mathematical operations

On a second thought, I'm not sure if this is correct. I think most(?) mathematicians consider there to be only 3 basic operations (addition, multiplication, and exponentation) since subtraction is just an inverse of addition and division is an inverse of multiplication.
>> No. 1010 [Edit]
>>274
how the heck do computers do multiplication then?
>> No. 1011 [Edit]
>>278
http://academic.evergreen.edu/projects/biophysics/technotes/misc/bin_math.htm

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1069 No. 1069 hide watch quickreply [Reply] [Edit]
Welp, it was bound to happen eventually: We ran out of IPv4 addresses.

If the IPv6 protocol was introduced nearly 20 years ago, why haven't we introduced it yet? All these protocols, CIDR, NAT, ect. they weren't solutions, they were temporary bandages. I'm betting that it was the corporate jews in the big chairs that didn't want to spend their jewgold on fixing it because "it's still working".

Though I'm hoping that the common home router will have the ability to translate the IPv6 address on the internet side into IPv4 addresses for personal computer use so we can keep using our old 2k or 9x computers (like I do for all my 9x era games), but of it don't I can deal with it, since XP supports IPv6 and there's always virtual box programs.

And before you say "we're not completely out", I understand that, and I know many large ISP's still have many unused IP addresses, but if we've allocated it all I think we're running pretty low.

http://www.pcworld.com/article/218666/icann_assigns_its_last_ipv4_addresses.html
>> No. 1072 [Edit]
I heard about this from by brother while we were talking about a week ago.
>> No. 1073 [Edit]
I hope this encourages an effort towards faster transition.
>> No. 1074 [Edit]
http://linuxconfau.blip.tv/file/4692762/
ipv6 is nowhere near ready for actual use.

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1013 No. 1013 hide watch expand quickreply [Reply] [Edit]
Lunar Eclipse tonight
you dig it?
1 post omitted. Click Reply to view.
>> No. 1015 [Edit]
It should be starting now where I live, but the moon still looks clear white...
I'm downloading shit now, so I'll still be awake for a while; will confirm when full eclipse is visible; would take pics, but from a cellphone? nah.
>> No. 1016 [Edit]
Raining. Hard



I'm actually quite frustrated considering I've been looking forward to this for months. But of course I'm never able to experience these things
>> No. 1017 [Edit]
Almost completely covered from where I am right now, pretty awesome.
>> No. 1018 [Edit]
>>80

JUST CONLUDED, in here. Really pretty; made me think about Lilith's Red Moon...

Anyway: my download have just finished too, so I'm gonna watch it. Have a good winter solstice, everyone; glad to have spent this (weird) seasonal year with you, brohnos.

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968 No. 968 hide watch quickreply [Reply] [Edit]
http://www.associatedcontent.com/article/6136806/voyager_1_launched_in_1977_on_verge.html

This kind of blew my mind, the fact that something we built is out so far, even if it's just a probe from the 70's. I know it's slightly old news, but considering how long Voyager 1's been out there I don't think a week makes much of a difference.
>> No. 969 [Edit]
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969
Poor Voyager 1.
>> No. 970 [Edit]
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970
>>76

I know wht you mean:

Sayonara... Voyager.

anyway: those sounds (whales's songs, aria da capo from Goldebrg variations) could probably be repeated someday, in the far future... or no; and those are all the options.

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1027 No. 1027 hide watch expand quickreply [Reply] [Edit]
Nasa announced it has discovered a bacterium that consumes arsenic and even uses it to construct its genetic material
thoughts?
15 posts and 1 image omitted. Click Reply to view.
>> No. 1043 [Edit]
>>63
I assumed he took a quote from the Fox News website or one of those shows where people submit comments like Bill O'Reilly's, maybe I'm wrong.
>> No. 1044 [Edit]
http://www.newscientist.com/article/mg14419490.800-microbes-have-arsenic-licked.html

>29 October 1994
>> No. 1045 [Edit]
It basically substitutes phosphorous as a building block for organic molecules. So it's not that surprising at all, since both phosphorous and arsenic are within the same period. It basically has the same function as phosphorous in these cells, except that it's much bigger than phosphorous. But that discovery also shows how extraterrestrial life could be radically different than living organisms on Earth.
>> No. 1046 [Edit]
Damn nature, you cool.

This is why I got into earth sciences.

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971 No. 971 hide watch expand quickreply [Reply] [Edit]
Part 1: Structure of materials

You can imagine materials being composed of atoms with springs attached to one another. A force is needed to pull the atoms apart and compress them closer together. The way these atoms are stuck together determine many properties of the material. Part 1 will deal with atomic structure of materials, including packing, the categories of structures and bond energy (how much energy needed to alter the structure).
15 posts and 6 images omitted. Click Reply to view.
>> No. 987 [Edit]
Part 3: Dislocations and ways to make metals stronger

Part 3(a): What dislocations are

Dislocations are essentially 'imperfections in the crystal structure'. The atoms in a crystal do not always line up perfectly, and there may be some abnormalities such as a missing atom or an extra atom which distorts the pattern of the lattice. Dislocations can travel through the crystal along 'slip planes' using a caterpillar-like motion. Diagrammatically, we use a perpendicular symbol to depict a dislocation. A typical engineering alloy will contain 100,000km worth of dislocations per centimetre cubed.

Dislocations may or may not be wanted in a material, depending on circumstances. Introducing more dislocations into a material tends to set up a 'forest of dislocations' which causes dislocations to get tied up in one another, stopping them (and the slip plane) from moving. This makes a material hard, but at the same time makes it more brittle and inflexible. Hardness might be desirable in a bridge girder which you don't want to wobble, but undesirable for steel used in springs.
>> No. 988 [Edit]
Part 3(b): Intrinsic lattice resistance to dislocations

For a dislocation to move, it needs to break and reform a bond between two atoms. This requires a force, and this resistive force is called the intrinsic lattice resistance, symbol Fi. Dislocations move when the slip planes slide over each other.

In metals, Fi is low because of the non-directional nature of the bonding which means that the atoms don't give a fuck that they're sliding. In contrast, ceramics have a high Fi because bonds between atoms are highly directional, and breaking one bond to move a dislocation implies breaking fifty million other bonds on the slip plane too.
>> No. 989 [Edit]
Part 3(c): Making metals stronger

In this section I will describe some techniques used to increase the overall lattice resistance of metals, and hence stop dislocations from moving. The movement of dislocations is the mechanism by which slip planes move, and on a macroscopic scale is 'bending' which is often undesirable.

Solid solution strengthening: Is basically 'alloying'. Consider this: with water, you can dissolve sugar into it and get a solution of water with sugar molecules interspersed through it. With metals, the same is true: you can 'dissolve' molten zinc into molten copper and receive a 'solution' of both.

How does this inhibit the movement of dislocations? Solid solution strengthening introduces impurity atoms into the crystal lattice. These impurities have different atom size compared other atoms, and so they distort the crystal lattice. Dislocations need more force/energy to move past these distortions. Two main factors are responsible for the increase in intrinsic lattice resistance: difference is atom size and the amount of impurities added. Copper and zinc have fairly similar atom size, so there needs to be a mixture of about 30% Zinc to 70% copper. Carbon and iron have a huge difference in atom size, so only 0.3% of carbon needs to be added to the Iron to get the same effect.

Precipitation hardening: Let us carry our analogy with sugar and water further. If you add lots of sugar to hot water and dissolve it all, you may find out that some of the sugar recrystallises out of the solution when it cools down. The same thing occurs with metal alloys. Some impurity atoms will 'precipitate', forming small particles of impurities inside the matrix of the alloy.

These precipitate particles impede dislocation movement. Dislocations are forced to either go around, or cut through these particles. If they go around the particle, the dislocation tends to leave traces of itself around the particle called 'Orowan loops', which themselves impede dislocation movement and get bigger and bigger with each passing dislocation.

Work hardening: This is basically working the metal to deliberately introduce more dislocations, and create a forest of dislocations to stop dislocation motion. The metal can be hammered, rolled, bent, d
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>> No. 990 [Edit]
Part 4: Fast fracture

Fast fracture is when cracks in a material expand rapidly, causing a catastropic failure of the material, even if its below yield point stress. For a crack to grow, there needs to be sufficient stress on the crack. To calculate this critical stress, we consider the work needed for the crack to grow. The work done by the load needs to be greater than the difference between change in elastic energy and energy absorbed at the crack tip (this crap doesn't make no sense.) Equation:

δW ≥ δUel - Gc.t.δa

Gc is the energy absorbed per unit area of crack, with t(delta)a being the new crack area. Gc is the measure of the materials 'toughness', and is how much energy is needed to propagate a crack. A high Gc means the material is tough and cracks have a hard time getting bigger (e.g copper), a low one implies the opposite (e.g ceramics).

Honestly I don't know what i'm talking about in this section.

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1019 No. 1019 hide watch expand quickreply [Reply] [Edit]
Gravitational Potential Energy: described by the equation

Ep = -G*m1*m1/r Where G is the universal gravitation constant, m1 is mass of planet 1, m2 mass of planet 2, and r the distance between the center of mass between planets. For various reasons, they put a negative sign in front of this equation. But you can't have negative energy! Can you figure out why theres a negative sign?
3 posts and 2 images omitted. Click Reply to view.
>> No. 1023 [Edit]
Would this possibly be a black hole?
>> No. 1024 [Edit]
if the force is being constructed as a vector the negative sign simply indicates its direction.
the direction being down toward the earth.
>> No. 1025 [Edit]
>>6
But this isn't force, but potential energy.

As distance between the two planets increases, the potential energy should increase. But the equation dictates that the potential energy will simply approach zero from the negative side. Whys that?
>> No. 1026 [Edit]
Because it is supposed to be negative.

>This potential energy is more strongly negative than the total potential energy of the system of bodies as such since it also includes the negative gravitational binding energy of each body. The potential energy of the system of bodies as such is the negative of the energy needed to separate the bodies from each other to infinity, while the gravitational binding energy is the energy needed to separate all particles from each other to infinity.

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