eurionize – add the eurion anti-copying mark
Some currency contains a pattern which instructs color copiers not to copy it. Markus Kuhn documented the pattern in this PDF and named it the EURion Constellation.
Eurionize is a program that marks a postscript document with the EURion Constellation, thereby preventing it from being copied on most color copiers.
Rainbow Moments Coloured Flame Candles
Our Rainbow Moments colour flame candles and lamps contain organic salts, inorganic salts
and safe metals such as magnesium that create the colour flames when they are burnt off.The candles are not made of wax. They are made of a combination of the specials salts and metals that make the colour flame, a bonding agent that keeps the candles strong and the main ingredient consists of citric acid crystals such as those used in food preservatives and children’s toys.
Rainbow Moments Coloured Flame Candles – Colour Your Occasions [via]
Sinister 7
I need a random number generator, but I want to integrate surrounding fields into the generation. I’ll start with a Logomatic as the base platform because it has the ADC channels of an LPC2138 broken out. I can also start with that firmware to hopefully minimize my work. And I’ll use the SD card for a custom message list. That should make it interesting. I’ll also need some kind of display…the Nokia knock-off and supporting breakout boards ought to do. Lastly I’ll need an accelerometer to tell when the device has been rolled over so I can generate a new answer – almost like an electronic Magic 8 Ball.
alwaysBETA » The Tale of the Mechanical Virus
A Google employee found that he couldn’t get a projector to work, and noticed the projector issue was spreading . . .
The problem I discovered was that one of the thin walls between the holes had broken and bent down, forming a ramp. When I plugged the DVI adapter into my computer, two of the pins went into the same hole, and the projector could no longer understand the output from my computer.
However, it doesn’t end there. When I plugged the DVI adapter into the broken socket, the ramp formed by the broken wall bent the corresponding pin upwards, forming a wedge with the adjacent pin. Then, when any other Mac user plugged the same adapter into their own computer, the pin wedge would press down on that same socket wall, breaking it and bending it down in the same fashion.
What I had discovered, in essence, was a mechanical virus. It infects Mac laptops and speads via the DVI adapters. An infected adapter will infect any computer that uses it, causing that computer to infect any adapters that it comes into contact with in the future, etc.
Wallace
My ultimate goal, for some reason, is to see if you can use genetic algorithms to “train” a computer to play Super Mario Bros. A genetic algorithm needs two key things: a way to generate candidate solutions (relatively easy, here) and a way to measure their “fitness” (or “goodness”) so as to decide which candidates live on to the next generation and which go the way of the dodo.
Of course, being a master of computer science, I won’t be satisfied by creating something that is only capable of playing Super Mario Bros. Nay, I want something that can, in principle, be applied to any Nintendo game. Naturally, a fitness function appropriate for Super Mario Bros. (whatever that might be) would be quite different than one appropriate for, say, Mega Man 2, to say nothing of something like StarTropics or (dare I say it) Final Fantasy.
[meta] Sorry for leaving you guys post-hungry. I should be done moving tonight–I started August 3rd. [/meta]
Paul Kuliniewicz » Wallace [via]
Methamphetamine lab awareness: Minnesota DNR
Methamphetamine lab awareness
Be aware
More and more illegal methamphetamine labs are being set up on public lands – state forests, state parks, wildlife managements areas, etc.
While out hunting, hiking, nature viewing or doing other outdoor activities, if you see what appears to be a methamphetamine lab, contact your local law enforcement agency or conservation officer immediately.
Fechner color – You know you’ve seen it
I actually have noticed this before reading the article. Kinda cool.
Fechner color is an illusion of color seen when looking at certain rapidly changing or moving black-and-white patterns. They are also called pattern induced flicker colors (PIFCs). Not everyone sees the same colors.
It is most commonly demonstrated with a device known as Benham’s top. It can also be seen in stoboscopic lights when flashes are set at certain critical speeds. The effect was noted by Gustav Fechner and Hermann von Helmholtz. The perceptual mechanism of Fechner color is not entirely understood.
When the disk is spun, arcs of pale color are visible at different places on the disk. One possible reason people see colors may be that the color receptors in the human eye respond at different rates to red, green, and blue. Or, more specifically, that the latencies of the centre and the surrounding mechanisms differ for the different types of color-specific ganglion cells.
Benham’s Top:
Leaky Bucket Algorithm
The leaky-bucket implementation is used to control the rate at which traffic is sent to the network. A leaky bucket provides a mechanism by which bursty traffic can be shaped to present a steady stream of traffic to the network, as opposed to traffic with erratic bursts of low-volume and high-volume flows.
Cavitation – Not related to dental hygene
I’ve always wondered where the bubbles came from, especially when a propeller is completely below the surface of the water. Read on the paragraph 2 for the answer:
Cavitation is a general term used to describe the behavior of voids or bubbles in a liquid. Cavitation is usually divided into two classes of behavior: inertial (or transient) cavitation and non-inertial cavitation. Inertial cavitation is the process where a void or bubble in a liquid rapidly collapses, producing a shock wave. Such cavitation often occurs in pumps, propellers, impellers, and in the vascular tissues of plants. Non-inertial cavitation is the process where a bubble in a fluid is forced to oscillate in size or shape due to some form of energy input, such as an acoustic field. Such cavitation is often employed in ultrasonic cleaning baths and can also be observed in pumps, propellers etc.
As an impeller’s (in a pump), or propeller’s (as in the case of a ship or submarine) blades move through a fluid, low pressure areas are formed as the fluid accelerates around and moves past the blades. The faster the blades move, the lower the pressure around it can become. As it reaches vapor pressure, the fluid vaporizes and forms small bubbles of gas. This is cavitation. When the bubbles collapse later, they typically cause very strong local shockwaves in the fluid, which may be audible and may even damage the blades.
The physical process of cavitation inception is similar to boiling. The major difference between the two is the thermodynamic paths which precede the formation of the vapor. Boiling occurs when the local vapor pressure of the liquid rises above its local ambient pressure and sufficient energy is present to cause the phase change to a gas. Cavitation inception occurs when the local pressure falls sufficiently far below the saturated vapor pressure, a value given by the tensile strength of the liquid.