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Perpetual Futility A short history of the search for perpetual motion. by Donald E. Simanek Popular histories too often present perpetual motion machines as "freaks and curiosities" of engineering without telling us just how they were understood at the time. They also fail to inform us that even in the earliest history of science and engineering, many persons were able to see the futility and folly of attempts to achieve perpetual motion. Sometimes a particular device comes to us with a label, such as "Bishop Wilkins' magnetic perpetual motion machine." Popular articles leave the impression that the inventor believed it was a perpetual motion machine. Bhaskara's Wheels. Villard de Honnecourt was born in the late 12th century and probably lived and worked in the north of France from 1225 to 1250. The most celebrated of his machine designs was for a perpetual motion wheel. Villard's diagram shows seven hammers, and he insisted on an odd (uneven) number of hammers, explaining 56. That's it.

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Hydroelectric Hydroelectric Power - Water power - micro hydro systems Micro hydro power is probably the least common of the three readily used renewable energy sources, but it has the potential to produce the most power, more reliably than solar or wind power if you have the right site. This means having access to a river or creek that has a high enough flow to produce useable power for a good part of the year. Many creeks and rivers are permanent, ie, they never dry up, and these are the most suitable for micro-hydro power production. A micro hydro turbine can take several forms, the most widely recognized of which would be the water wheel, used extensively for grain grinding up until this century.

Le garde-temps de Cox - Wikipedia, l'encyclopédie libre Cox timepiece winding switch Design and history[edit] Related to this is Cornelis Drebbel's device of 1610 (though it is unknown whether Cox knew of it). It was a machine that told the time, date, and season. Interesting High-speed Video Clips The video clips below were filmed with a special high-speed camera. The super slow-motion playback lets you visualize effects that cannot be seen with the naked eye or with a standard video camera. NOTE: No humans or animals were hurt during the filming of any of these clips.Also, all humans (and my pet dog) were willing and eager participants.Any discomfort was willingly accepted in the interest of science. The video clips are Windows Media files.Click on the icon below if you wish to download the latest free player.

An Overview of Cryptography 1. INTRODUCTION Does increased security provide comfort to paranoid people? Or does security provide some very basic protections that we are naive to believe that we don't need? During this time when the Internet provides essential communication between tens of millions of people and is being increasingly used as a tool for commerce, security becomes a tremendously important issue to deal with. There are many aspects to security and many applications, ranging from secure commerce and payments to private communications and protecting passwords. Tesla Technology: 5 Bladeless Turbines About to Revolutionize Energy Production “Every home in America can run on wind energy. In fact these units can be installed on existing power poles in rural areas, to catch the wind and send its energy back to the plant.”- Raymond Green, Inventor In 1913, Inventor Nikola Tesla patented a bladeless steam turbine that he claimed was the most efficient and the most simple rotary engine ever designed. Due to a lack of high-quality materials, Tesla was never able to properly build his engine.

Pendule Atmos - Wikipedia, l'encyclopédie libre Atmos is the brand name of a mechanical clock manufactured by Jaeger-LeCoultre in Switzerland which does not need to be wound manually. It gets the energy it needs to run from temperature and atmospheric pressure changes in the environment, and can run for years without human intervention. Its power source is an internal hermetically sealed capsule containing a mixture of gaseous and liquid ethyl chloride, which expands into an expansion chamber as the temperature rises, compressing a spiral spring; with a fall in temperature the gas condenses and the spring slackens.[1] This motion constantly winds the mainspring.

A new formula for avoiding supermarket queues Supermarket queues are dreaded by many. In the TV series ‘Supernatural’, people standing in an endless queue are used as an example of what hell really looks like. (Photo: Colourbox) In researcher Kebin Zeng’s office hangs a big whiteboard filled with mathematical formulas and functions. Complicated as it looks, it’s all about solving everyday problems such as supermarket queues. ”You could say that I convert everyday life into mathematical models.

Living Off-Grid: Our Micro Hydro Alternative Energy System Blue Energy Published on March 24th, 2009 | by Jennifer Lance As a follow up to Sean’s post on Micro Hydro Essentials, I thought I would share an overview of my system, which has powered my home for over 13 years. We are fortunate to live on rural mountain property in Northern California with a creek that is not seasonal, although the volume of water does drop significantly during the arid months of summer. The beauty of hydro power is that it produces power 24 hours a day and is not dependent upon weather patterns, such as sun and wind. The drawbacks are having to maintain the system by cleaning the intake and dealing with varying creek flows. Photo by jennifer lance

Comment construire un générateur hydroélectrique à petite échelle They have developed various systems that convert the energy from nature in electricity and many of these systems could be built at home, on a smaller scale, in order to reduce electricity consumption. After we saw how to produce electricity using magnets or wind power, it is time to talk about those people who live near a river. In this case, the best way to produce electricity is represented by a small-scale hydroelectric generator made at home. Often called as a low-impact hydro, micro-hydro or run-of-stream hydro generator, this system is not very hard to build. To build such a micro-hydro generator you must follow these steps: A.

An App That Encrypts, Shreds, Hashes and Salts The Wickr app. When it comes to mobile apps and social networks, the devil, increasingly, is in the default settings. Companies have little, if any, incentive to let users opt out of services that siphon their personal data back to the advertisers who pay their bills. Nor do companies have any legal mandate to secure users’ personal information with hacker-proof encryption.