13 more posts in this thread. [Missing image file: marble_adder_temp.jpg]
me and a friend are designing a mechanical computer.
we have the basics laid out, and are now trying to optimize the machines that perform the basic operations like addition and multiplication.
pic related is an adder that works pretty well, and we've decided to use it for our actual adding machine.
youtube video of it working:(not ours) http://www.youtube.com/watch?v=GcDshWmhF4A
we're now trying to design a proper multiplication machine that takes two rows of marbles(marble=1, no marble=0) and gives us the result of multiplying the two numbers together.
we have some intermediate results, they basically boil down to this:
decimal multiplication like for instance 123*456 can be written as 1102¤456+2101¤456+3100¤456 , which does not help a lot. but since we are working with binary numbers, if we multiply 1011 and 0011 we can write that as 1*0011<<3+0*0011<<2+1*0011<<1+1*0011<<0 which is a lot easier to implement in a physical machine because we can just duplicate the second number(0011) four times, shift the duplicate rows by 0, 1, 2 and 3 which is piss easy in a marble machine, and then discard the nth duplicate row if the nth bit of the first number is 0, and after that just add all the rows in a cumulative adder like pic related.
Ok, so, we want to do this more efficiently, because duplicating that much marbles is really slow and error-prone. also it makes for a very big parts-list.
So /diy/, any suggestions?
because what we thought was that the total number of marbles going in is always larger(or equal) than the amount of marbles coming out, so we should be able to do this without any duplicators right?
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Hey /diy/, advise me.
I have four retired racing greyhounds. Our backyard is fenced and they go out there to do their business. In the winter, when the sun goes lower on the horizon, the porch roof shades the ground where the dogs land when they jump off the porch and enter the grass. As a result when we get rain, it turns into a muddy mess. I put a tarp down to keep them from tracking the mud into the house, but this doesn't let it dry (which takes forever b/c its always shaded). I put in the black drainage pipe last winter and it helps. Before, when it rained the whole area was a mess. Anyhoo, what are some ideas to make this situation better?
tl;dr how to remedy mud in shady spot?
pic related. its the spot
5 more posts in this thread. [Missing image file: 7025662063_da113f7d78_b.jpg]
Long story short, frustration with whether or not I should continue attending college and 'what should I do with my life' has lead me to this question.
Has anyone ever heard of any collectives that focus on autodidacticism?
Basically the closest thing one can get to a free higher-learning education without the degree or the fees, and it'd be a great way to find out what you're actually interested in before blowing all that cash. Also, if you're like me, it's always a great motivator to study in an environment with others who are doing the same.
I only come here once in a blue moon, so if anyone's interested or can enlighten me a bit, hit me up on either:
AIM: pleasurepusscake (preferably)
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I've been trying to get in better shape recently, and I'm curious if you guys have any do it yourself type of things you use to work out. I already have a weight set and a benchpress made out of an old howitzer shell box from the war in Vietnam, but I want something to do pull ups with, boxing bag or whatever they're called, and if you have any ideas, how to simulate running or jogging without a lot of space. I live on a dangerous road and I don't wanna go running out in the freezing rain.