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    Mapping computer state changes as a space.

    I want to see if we can map the space that is computable programs. You wouldn't consider complex problems, once you mapped the simplest problems into a space of points you can get a distribution. You may see that these clump. Seeing as several of the variables are proportional to the history of...
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    Looking for a critique: reactive black body radiation device

    I want to get a half convex lens (thick in the middle, flat on one side). And coat it in thermally and optically reactive transition filters. They are to be segmented so to reduce spread of filtering. This will give a view of the sky with any bright light inhibited at the focus. Next to the...
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    Sky temperature profiles and black body radiation

    I want to know, excluding the sun with an appropriate boundary, whether it is possible for the balance of bbr to be positive for outerspace rather than on earth? I am thinking of a half convex with an active polariser across-the outer surface which allows through most radiation below the...
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    Water/land detection/differentiation from a quadcopter

    Hello, I want to have a quadcopter drone type set up which can tell how far from land it is. I would go for GPS but I want it to take into consideration the tide, and in general I'm only talking a distance of 50-200m (within shore fishing distance). The ideal system would be a drone that can...
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    Advice on building a radio transmitter in the Radio Control band

    << Mentor Note -- post separated out of a different thread to deal with a separate question >> Hi, I am looking transmit as well as receive power within close proximity. Currently I am looking at 27.255 MHz AM in the citizens band. It is listed on Wikipedia and in statues I found to be for...
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    Simulate a reality by exploiting geometric solutions

    It will essentially be The Matrix. Except every one who plays will be God's and they get to build the world up from atomic structure. The main mechanism of action is people finding stable formations can publish them. You get to name an object and it becomes available as a clip board item to...
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    Where would you buy carbon nanotubes?

    Wouldn't have to be long ones. Cheap and cheerful amounts. A google search brought up one called, any one had experience with them?
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    Could one use a capacitor to enhance a capacitive stylus?

    I don't well understand capacitance and its use in touch screens. Just had a crazy idea that you could involve a charged capacitor to enhance the accuracy of a stylus.
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    Buckyballs surface chemistry

    I've got a project I'm interested in. Essentially its modifying a melamine foam so its thermal conductivity is at least halved. Was thinking some type of buckyball filler in the matrix might be a ticket. However someone pointed out it maybe a worry about how it would affect the cell...
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    Maxwells demon

    I had the concept of scaling up Maxwells' demon experiment to a marco scale. Replacing molecules of gas with light, rigid, balls. Perhaps coated in magnets with varying poles so they never touch (non-interacting). Would suspend them in a thin fluid with neutral buoyancy.
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    What would the products of photolysis degredation of PET plastic be?

    Interested in this because plastic drinking bottles have a taint to them when left out in the sun. I gather its from UV degredation of the PET plastic. I'd like to find a catalyst that would allow the PET byproducts to be non water soluble/sequester or even evaporate.
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    Questions about static electricity in automobiles

    So, I don't want to disclose why I want to know about this because its to do with a friends invention and it would be unfair to publish too much information without his consent. That's my disclosure so to speak. I'm interested in how static electricity is managed in vehicles. I remember...
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    Micro-organisms in the fridge

    Hi, I'm looking into making a meter that gives an indication of bacterial load present in ones fridge. Currently I am thinking a device that measures CO2 and alcohol levels once the fridge is in a steady state (ie the door not open for some amount of time). I have a rough concept that...
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    Looking for a specific dye

    Hi folks, I'm looking for a dye that absorbs strongly around the 490nm range. Sort of a red/orange I guess. I cannot find a lot of data on absorbency by dye manufacturers, will begin emailing them shortly. Key word searches tend to bring up dye absorbency in relation to materials not light...
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    Controlling activation of a circuit with a moisture meter

    Hi, I'm building a make shift spectrophotometer. It's only concerned with a narrow bandwidth of visible light. I'm using two LEDs, one which is lit, the other which is co-incident with a sample in between absorbing light from the lit LED. I pass the voltage of the receving LED to an LM358...
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    Multi LED circuit controlled by photodiode

    Hi, so. I don't know a lot of electronics but this is effectively what I'm trying to create: A photo diode controls the circuit, I assume they give out a current proportional to the intensity of the light it receives. The ciruit, depending on the light intensity will light up different...
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    How would I find a UV-VIS spectra of human urine?

    Preferably I would like to find a UV-VIS absorbance spectra of urine. I have found ones that focus on the deep UV range, and one that had fluorescence peak information. Any help would be appreciated.
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    Semi-compressible encapsulated gas suspension as a working fluid

    Been playing with this idea It's been boiled down to some sort of elastomeric beads, filled with a suitable gas/fluid/liquid (depending on pressure/temperature) suspended in a liquid. The idea is to increase pumping and compression...
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    Using magnetism to control the structure of concrete

    So this is my idea: make concrete using iron sand, preferably one with a decent ferromagnetic interaction. As the concrete sets, apply a magnetic field. The ferromagnetic particles align to the field creating a structure within the concrete. Possible to coat the iron sand in a retarding...
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    Want to set up a constant magnetic field to do experiments under

    Hiya, So I want to do some experiments with concrete curing under a magnetic field. The samples would need to be approximately a 2" diameter tube maybe 8" long. I'm not that aware of how a magnetic field would behave any more, been awhile since I did any physics outside of classical...
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    Reverse solar trap

    I've been thinking about this on and off for awhile now. It first started with the idea of a solar trap. Solar trap being something like having a solar collector focusing light on a container of water, having an infra red barrier around the container, and a black body at the centre. Incoming...
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    Miscellaneous Definite Integrals

    Homework Statement show that \int^{∞}_{0}\frac{sin^{2}x}{x^{2}}dx= \frac{\pi}{2} Homework Equations consider \oint_{C}\frac{1-e^{i2z}}{z^{2}}dz where C is a semi circle of radius R, about 0,0 with an indent (another semi circle) excluding 0,0. The Attempt at a Solution...
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    Using Newtonian field equation to find the gravity inside a sphere

    Homework Statement work out g field at a distance r=R/2 from the centre of a spherically symmetric body of radius R. Homework Equations \nabla^{2}\psi=4\pi G \rho \psi=G\int_{V'}\rho\frac{1}{|\vec{r}-\vec{r^{'}}|}d^{3}\vec{r^{'}} -\int_{V}\nabla\cdot g dV = \int_{V}\rho dV...
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    Proving vector calculus identities using summation notation

    Homework Statement \frac{∂x_{i}}{∂x_{j}} = δ_{ij} Homework Equations \vec{r} = x_{i}e_{i} The Attempt at a Solution \frac{∂x_{i}}{∂x_{j}} = 1 iff i=j δ_{ij} = 1 iff i=j therefore \frac{∂x_{i}}{∂x_{j}} = δ_{ij} Homework Statement r^{2} = x_{k}x_{k} Homework...
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    Piezoelectric element in contact with a metal

    Hi all, I'm using ABAQUS to do a bit of material modelling. I don't have concrete understanding of this but I'll explain what I am trying to do: Essentially a piezoelectric and a metal in contact under strain. The piezoelectric produces an electric potential which I hope can be...
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    Looking for information on piezomagnetic materials

    Could someone help me understand the strength of fields that can be produced with piezomagnetism? I have not had much luck with searches for these materials.
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    Calculating electric field produced by micro crystalline piezoelectric grains

    Hi, I'm researching a potential masters project involving incorporating piezoelectric crystals into a ceramic so that when a load is experienced the electric field generated encourages the electroplastic effect in the bulk phase so that it becomes more plastic and inhibits crack formation...