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*Climate Resilience Needs Community Roots, Mar 11. [https://www.demsoc.org/blog/climate-resilience-needs-community-roots] "One message is clear: cities can better address climate challenges by embedding democratic principles, such as collaboration, power-sharing and transparency in their climate action work." ...[[Europe news]] | *Climate Resilience Needs Community Roots, Mar 11. [https://www.demsoc.org/blog/climate-resilience-needs-community-roots] "One message is clear: cities can better address climate challenges by embedding democratic principles, such as collaboration, power-sharing and transparency in their climate action work." ...[[Europe news]] | ||
*A new direction for public engagement with energy and climate change, Mar 9 [https://socialsciences.nature.com/posts/a-new-direction-for-public-engagement-with-energy-and-climate-change] ...[[Climate news 2021]] | *A new direction for public engagement with energy and climate change, Mar 9 [https://socialsciences.nature.com/posts/a-new-direction-for-public-engagement-with-energy-and-climate-change] ...[[Climate news 2021]] | ||
| + | *“When democracy is conducted at a human scale, it helps create what looks like superhuman wisdom.” How the state of [[Vermont]] does it, Mar 9 [https://www.thealternative.org.uk/dailyalternative/2021/3/13/vermont-slow-democracy-superheroes] | ||
*The climate crisis can't be solved by carbon accounting tricks, Simon Lewis, Mar 3 [https://www.theguardian.com/commentisfree/2021/mar/03/climate-crisis-carbon-accounting-tricks-big-finance] ...[[Climate news 2021]] | *The climate crisis can't be solved by carbon accounting tricks, Simon Lewis, Mar 3 [https://www.theguardian.com/commentisfree/2021/mar/03/climate-crisis-carbon-accounting-tricks-big-finance] ...[[Climate news 2021]] | ||
*Future generations bill sounds 'namby pamby' but it's start, says Lord Bird, Feb 20 [https://www.bbc.co.uk/news/uk-politics-55920793] ...[[UK Climate news 2021]] | *Future generations bill sounds 'namby pamby' but it's start, says Lord Bird, Feb 20 [https://www.bbc.co.uk/news/uk-politics-55920793] ...[[UK Climate news 2021]] | ||
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{{Read more|Community action for sustainability}} | {{Read more|Community action for sustainability}} | ||
Revision as of 12:07, 17 March 2021
Appropedia shares knowledge to build rich, sustainable lives (read our vision and mission).
Explore 9,336 resources and solutions for sustainability, appropriate technology, poverty alleviation, permaculture and more!
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Community Action for Sustainability News
- Climate Resilience Needs Community Roots, Mar 11. [1] "One message is clear: cities can better address climate challenges by embedding democratic principles, such as collaboration, power-sharing and transparency in their climate action work." ...Europe news
- A new direction for public engagement with energy and climate change, Mar 9 [2] ...Climate news 2021
- “When democracy is conducted at a human scale, it helps create what looks like superhuman wisdom.” How the state of Vermont does it, Mar 9 [3]
- The climate crisis can't be solved by carbon accounting tricks, Simon Lewis, Mar 3 [4] ...Climate news 2021
- Future generations bill sounds 'namby pamby' but it's start, says Lord Bird, Feb 20 [5] ...UK Climate news 2021
Selected page
The paraboloid is an interesting shape with some amazing qualities. It has the power to concentrate light, electronic waves, sound, etc. to its focus at the center. To find the focal point of a paraboloid, one must use the formula, [math]y=p*x^2[/math], where p is a constant. The variable y is the depth of the dish, and x measures the distance from the center axis to the maximum circumference of the dish. You have to pretend that there is an x axis going through the center of the base of the dish and a perpendicular y-axis passing from the center of the base of the dish to the focal point. The two numbers, x and y, represent a point on the paraboloid, and from that, you are able to determine where the focus is (see parabolic shape calculation).
Parabolic cookers have been used for centuries now. The idea to concentrate light using curved mirrors was developed by the Greeks, Aztecs, Incas, Romans and Chinese. The Incas used bronze and gold for their mirrors and they built structures that were several stories high. This technology seems to have appeared around the same time for each of the civilizations. It is thought that Archimedes harnessed the technologyW to defend Syracuse from invading Roman fleets in 212 BC.Selected gallery
Selected quote
Nothing compares to the simple pleasure of a bike ride.
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