Polygonal Spiral The length of the polygonal spiral is found by noting that the ratio of inradius to circumradius of a regular polygon of sides is The total length of the spiral for an -gon with side length is therefore Consider the solid region obtained by filling in subsequent triangles which the spiral encloses. -gons of side length , is The shaded triangular polygonal spiral is a rep-4-tile. Extraordinary BMX Tricks Categories October 25, 2010 1:02pm By Rowdy Joe Videos Extraordinary BMX Tricks These are not your everyday tricks! Runner HIts Girl On Racetrack Another Parkour Flip Flop Comments Related Posts Recommended Posts
Internet Streaming 101: How To Watch Live TV Online Have you ever missed your favorite television show one week and wanted to watch it before the next week’s new episode aired so that you wouldn’t be completely lost (Fans of “24” and “Lost” can certainly relate to this). Have you parked yourself in front of your television to watch a football, basketball, or soccer match only to realize that the game isn’t playing in your market? Have you ever wanted to watch foreign newscasts only to realize that your cable or satellite provider doesn’t provide the coverage you want? Well, you can spend a lot of money and invest in a satellite dish, TiVO, and premium sports and pay-per-view packages. Getting Started Obviously, the most important thing you’ll need is a high-speed internet connection. Most sites are built for PC users. Live Television There are many sites out there that broadcast live television from stations all over the world. Networks with Free On-Demand Content American Networks: British Networks: On Demand TV Shows On Demand Options:
DISCERN Artificial Neural Network - How to Build a Schizophrenic Computer Justin Ruckman/Flickr Advertisement - Continue Reading Below Schizophrenia is one of the most infamous and mysterious mental disorders. Attempting to get to the root of the problem, scientists recently came up with an extraordinary solution: They built a schizophrenic computer. In a study published in the online version of Biological Psychiatry in March, researchers altered an artificial neural network capable of learning language and stories, to the point where it started "acting" schizophrenic. People who suffer from schizophrenia often have difficulty thinking logically or discerning what is real or not real in their lives. To make a schizophrenic computer, they began with an artificial neural network called DISCERN that Miikkulainen has been working on intermittently since the 1990s. Hoffman and his colleagues then started to tell simple stories to the computer. In DISCERN, the process begins in a module called the sentence parser, which examines each sentence one word at a time.
Khan Academy Harvesting Chemicals from a Battery This tutorial shows how to take apart a spent zinc-carbon dry cell of the common household type. Besides making for an interesting object lesson in electrochemistry, taking apart a spent D-cell, for instance, allows you to salvage many materials which can be of use to amateur chemists–materials which would otherwise probably end up in a landfill. Separated from their reactive components, the leftover parts of the battery can be safely added to most municipal recycling streams. A zinc carbon cell (Wikipedia) contains manganese dioxide, which, among other things, is useful as a catalyst in the production of oxygen gas from hydrogen peroxide. Note that the battery in this tutorial is a zinc-carbon dry cell.
Light Touch projector makes any surface a touchscreen A previously little-known company from the UK called Light Blue Optics has demoed a projector at CES which allows users to interact with the light image as if it were a touchscreen. The Light Touch throws a 10-inch image at WVGA resolution at incredibly short distances thanks to the holographic projection technology involved. At the same time the infra-red touch sensitive system allows users to interact with social networks, multimedia sharing and any other applications that can use the Wi-Fi or Bluetooth support in the device to connect to the Internet. It comes with 2GB of onboard flash memory, a microSD card slot for expanding the storage and the battery life will last 2 hours. UPDATE: Two years on and although Light Blue Optics doesn't seem to have come up with the goods, others have. - Prodigy projection keyboard iPhone case turns any surface into a keyboard
How Long Can a Hard Drive Hold Data Without Power? - Lifehacker Longevity of backups depends primarily on condition and handling. I design a lot of disaster recovery systems and over the last few decades I've found that: Magnetic drives are fairly reliable when unplugged, but you'll still need to cycle them out over the years - My most common problem was the bearings and motors seizing causing drive failures. I've found that temperature is the primary deciding factory and potentially humidity another contributing factor. In datacenters that store the drives in hotter than room temp areas I've always had a higher drive failure rate from DR disks that are typically only plugged in once a month than the locations that have the same usage but store them in a cooler location. Old lubricated bearing drives were the worst for long term storage, they'd seize up if you didn't spin them up regularly (or at least that was my experience). Flash drives are surprisingly robust - USB has been around a surprisingly long time in the same format.