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Do³±czy³: 09 Maj 2014
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 gw2 gold Buildings and clothes could melt to save energy |
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Buildings and clothes could melt to save energyPhase-change materials that freeze at around room temperature could revolutionise energy storage, cooling things that are too hot and warming them later on THE sun has risen, and a brand new building on the University of Washington's campus in Seattle is about to melt. <a href="http://www.goldvk.com/Game.gw2_us.Guild Wars 2.gw2.Gold.Info.aspx">gw2 gold</a> It is no design flaw: encapsulated within the walls and ceiling panels is a gel that solidifies at night and melts with the warmth of the day. Known as a phase change material (PCM), the gel will help reduce the amount of energy needed to cool office space in the building - scheduled to house the molecular engineering department when completed this month - by a whopping 98 per cent. PCMs don't have to be as high-tech as this, of course. We have been using ice, a phase change material that melts at 0 °C, to keep things cool for thousands of years. But advances in materials science and rising energy costs are now driving the development of PCMs that work at different temperatures to help people and goods stay cool or warm, or to store energy. PCMs are attractive energy-savers because of their ability to absorb or release massive amounts of energy while maintaining a near-constant temperature. "To melt ice takes the same amount of energy as would be required to warm an equal volume of water by 82 °C," says Jan Kosny of the Fraunhofer Center for Sustainable Energy Systems in Cambridge, Massachusetts, who began to explore the potential of PCMs three decades ago by looking at beeswax as a way to store heat from the sun. The reason PCMs are so useful is because energy is needed to break the molecular bonds between atoms when a substance melts, and is released when bonds are formed as it solidifies. The "bioPCM" gel in the university building , derived from vegetable oils, will be "charged" each night when windows automatically open to flush the building with cold outdoor air. The solid gel then absorbs heat as it melts the next day. The idea is the same as using thick concrete or adobe walls, which reduce indoor temperature fluctuations, but only a fraction of the material is required. "Our bioPCM is 1.25 centimetres thick yet it acts like the thermal mass of 25 centimetres of concrete," says Peter Horwath, founder of Phase Change Energy Solutions , based in Asheboro, North Carolina. A recent report by technology research firm Lux Research predicts the use of phase change materials in buildings will grow from near zero today to $130 million in annual sales by 2020. Meanwhile, a number of other applications are emerging. <a href="http://www.goldvk.com/Game.gw2_us.Guild Wars 2.gw2.Gold.Info.aspx">gw2 gold</a> <a href="http://www.goldvk.com/Game.gw2_us.Guild Wars 2.gw2.Gold.Info.aspx">gw2 gold</a> UK-based Star Refrigeration is using carbon dioxide, which changes phase from liquid to gas at a very low temperature, to keep data centres cool. Heat emitted by today's high-performance server farms can overwhelm even the most advanced water cooling systems. By piping CO 2 through heat exchangers, the company recently demonstrated an ability to pull nearly twice as much heat from the computers as the systems used at present. In western China, PCMs derived from yak butter and local plant oils are helping yak herders keep warm. The material is encased in plastic and then woven into traditional clothing. It melts as herders work up a sweat walking to mountain pastures then, when they stop moving, the pent-up heat is slowly released, keeping them warm as they watch their herds. More than 100 families are now using the materials as part of an ongoing pilot project that also includes bed rolls warmed by cooking stoves in the day to keep people warm at night. "Families that use them are starting to see a significant difference in the amount of fuel they need," says Scot Frank of One Earth Designs, also based in Cambridge, which developed the compounds. Another promising application for PCMs is vaccine delivery in developing countries. Vaccines need to be kept cold during transport, which is a challenge in countries with limited refrigeration. They are typically packaged in ice, but their effectiveness can be severely compromised if they freeze. Using materials that change phase between 4 and 8 °C, US packaging manufacturer Sonoco says it has developed a solution that can keep vaccines cool for up to six days. Sonoco is now testing the Greenbox with a non-profit biotechnology developer called PATH, to meet World Health Organization standards. Harnessing PCMs for energy storage could also give solar power a boost. Today systems that concentrate solar thermal energy rely on liquid salts to store heat. This allows power plants to produce energy when the sun is not shining, but requires massive amounts of liquid and large, well-insulated storage facilities. By using chemicals that change phase instead, German manufacturer SGL Carbon says it can reduce the volume of storage material required by roughly two-thirds. The company is currently testing a prototype. For Kosny, all of the recent interest in PCMs is something of a vindication. "Ten years ago, when I argued for the development of phase-change materials, no one was interested," he says. "Now we can't seem to develop these materials fast enough." Subscribe to New Scientist and you'll get: New Scientist magazine delivered every week Unlimited access to all New Scientist online content - a benefit only available to subscribers Great savings from the normal price Subscribe now! xboter 2014
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| Pon Maj 12, 2014 15:34 |
   
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| Pon Maj 12, 2014 15:34 |
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aJ5dY4aD9y
Do³±czy³: 09 Maj 2014
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| guild wars 2 gold How to Replace the Aileron Servo on the Pa |
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How to Replace the Aileron Servo on the Parkzone Ultra Micro F4U CorsairGA_googleFillSlot("games_hub_content_250x250"); Simple Aileron Replacement There is nothing more fun than flying radio control airplanes on a cool morning with my son. We love getting up at sunrise and hitting the sports field before it gets busy with people. We fly the Hobbyzone Champ, a great three channel plane, with an upgraded motor (read about how easy it is to make that modification at this link . It is a great 10 minute job that will really add some UMPH to a great little plane. After a while, we started to look for something a little more challenging and bought the Parkzone Ultra Micro F4U Corsair. In hindsight, this probably wasn't my best choice as the low wing setup coupled with ailerons really pushed the limits of our developing skills. Oh well! Nothing quite like a challenge to keep the hobby interesting! It's a good thing that these hobby grade radio control planes are made so well. We sure did put this one to the test. After one particularly inept landing on fine gravel, the aileron servo stopped working. We were able to dislodge the particles and got the servo working again (for a little bit at least). Unfortunately, the next time we took it out, there was no movement at all from that side. Nothing we did could get the long throw servo moving. It was time to order the replacement part. See all 7 photos Parkzone Ultra Micro F4U Corsair Parkzone Corsair Replacement Servo Replacement Servo Mechanics:Ultra Micro Long Throw Look for the Ultra Micro Long Throw Servo Part SPM6832 Amazon Price: $6.43 List Price: $11.99 Parkzone Ultra Micro F4U Corsair BNF PKZU1680 This is a fun four channel RC plane. Amazon Price: $143.33 List Price: $154.99 See all 7 photos Urgh! My Servo stopped working! First off, if you are wondering what the semicircular white marks are around the aileron, please check out my article on how to protect them using packaging for eggs. Of course, if I was smart, I would have replaced the servo BEFORE I installed the protection...I realized too late that my bad landing actually damaged the electronics. A couple of days later, the servo (Part Number AS2000L) **Thank you Daw for the correct part number!** arrived from Amazon. It was time to get busy. The first step was to carefully cut the stickers holding the fuselage top to the body. It lifts straight off and will reveal the inside of the plane where all of the electronics are safely housed. The next step is to remove the pushrod linkages (those are the small diameter metal rods that connect the control horn on the servo flap to the servo itself). You may need to use a pair of needle nose pliers to bend the tip of the pushrod to free it from the mechanism. <a href="http://www.goldvk.com/Game.gw2_us.Guild Wars 2.gw2.Gold.Info.aspx">gw2 gold</a> It is not a big deal as it can easily be bent back into place when you are done. See all 7 photos Carefully remove the servo. Use a hobby knife to gently remove the servo from the foam standoffs. Note : Do yourself a favor and try to keep as much of the foam as possible attached to the wing. If too much is cut off, you will need to build it back up before replacing the servo. See all 7 photos Gently remove it from the wing of the Corsair The picture at the right shows the servo cut free of the wing. I kept the wires taped down during this step just to keep them out of the way. Go ahead and cut the tape at this point to free the wires. I started to pull the tape off, but it pulled up some of the blue coloring of the wing. See all 7 photos Unplug the offending servo from the board. It is one of the two white plugs on the left in the picture. Unplug the servo lead from the board. It will be one of the two white plugs on the left hand side. <a href="http://www.goldvk.com/Game.gw2_us.Guild Wars 2.gw2.Gold.Info.aspx">guild wars 2 gold</a> Be gentle because if you inadvertently damage the board, you may have another repair on your hands. Hot Stuff Super T Instant CA Glue, 2 Ounces Amazon Price: $7.74 List Price: $10. <a href="http://www.goldvk.com/Game.gw2_us.Guild Wars 2.gw2.Gold.Info.aspx">guild wars 2 gold</a> 50 See all 7 photos Remove the connecting wires by treading it through the body. The Hardest Step! I was lazy and tried to feed the white plug through the small gap between the wing and the fuselage. My stubbornness got the best of me and it took me several minutes to get it aligned just right to pull it through. Once you get it lined up with the hole, it is easy to gently pull it through. The servo and wiring are now completely removed from the plane! See all 7 photos After installing, test the servo BEFORE putting the body back together. Woohoo! It works! Replace with the new mechanism The steps to put the new servo into place are easy. Follow the directions above in reverse order! There are only a couple of tricks I would recommend: Only use a drop or two of CA glue when attaching the servo back to the foam standoffs. That is powerful stuff, and you really don't need to add much. Test that the servo is actually working correctly BEFORE you reassemble the fuselage. Check the throw of the servos to make sure the left and right ones are operating in equal, but opposite directions and are of similar throw distance. If the neutral position of the servo is NOT in line with the wing, you may need to adjust the pushrod linkage. Simply squeeze or pry apart the linkage to make is shorter or longer. LASTLY! Install a Servo Protector before flying next time! GA_googleFillSlot("games_hub_share_520x280"); Last updated on April 22, 2013 xboter 2014
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| Pon Maj 12, 2014 16:29 |
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aJ5dY4aD9y
Do³±czy³: 09 Maj 2014
Posty: 129
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| guild wars 2 gold Augustin Louis Cauchy - CECI Math Wiki |
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var isAdmin = false; var closeAd = function(){ $j('#house-ad-1').parent().hide(); if($j.cookie('hide-house-ad-1')) closeAd(); $j('#house-ad-1 .close').click(function() if (isAdmin){ window.location = '/_admin/start/ads' else closeAd(); $j.cookie('hide-house-ad-1', true, {expires: 365, path: '/'); } }); }()); By: Remi Casier Augustin Louis Cauchy was a French mathematician born on August 21, 1789 in Paris, France. Cauchy was the eldest of all of his siblings and son of Louis Cauchy. Cauchy began an early education from his father and was the particular interest in Lagrange, a visitor to the Cauchy home. In 1802, from the recommendation of Lagrange, Cauchy went to a school where he spent two years studying classical language. In 1805 Cauchy entered a math school and graduated two years later, when he entered an engineering school. After a few short years of an engineer, Augustin Louis decided to devote himself to mathematics. In 1833 Cauchy was summoned by the king Charles X of France to be a tutor for his grandson, and returned home in 1838. Cauchy spent most of his time in the Collège de France, which is a higher education and research establishment, despite several encounters with is strong religious beliefs. Cauchy died May 23, 1857 in Sceaux, France. Cauchy had influential work in nearly every branch of mathematics, with nearly 800 publications, especially on the theory of functions, integral and differential calculus and algebraic analysis. Cauchy’s first major work occurred in 1805, with the simple solution to the problem of Apollonius. Cauchy continued to solve and generalize many other elegant problems throughout his years. Cauchy gave several important theorems in calculus and complex analysis and began the study of permutation groups. Perhaps one of Cauchy's most well known theorems is the Cauchy Integral Theorem. The Cauchy Integral Theorem is a complex analysis that states about the line integrals for holomorphic functions in the complex plane. If $f(z)$ is analytic in some simply connected region, then (1) \beginalign \oint_y f(z)dz=0 \endalign For a multiply connected region, (2) \beginalign \oint_C_1 f(z)dz=\oint_C_2 f(z)dz \endalign Bibliography O'Connor, JJ (1997, January ). Augustin Louis Cauchy. Retrieved February 25, 2008, from The MacTutor History of Mathematics archive Web site: http://www-history.mcs.st-andrews.ac.uk/Biographies/Cauchy.html Cauchy, Augustin-Louis, Baron. (2008). In Encyclopædia Britannica. Retrieved February 25, 2008, from Encyclopædia Britannica Web site: http://www.britannica.com/eb/article-9021867 Weisstein, E.W.Cauchy Integral Theorem. Retrieved February 25, 2008, from MathWorld Web site: http://mathworld.wolfram.com/CauchyIntegralTheorem.html Show Comments WIKIDOT.forumThreadId = 43807; Hide All Comments Unfold All Fold All Fold Nathan B 06 Mar 2008 14:46 Hey Remi, I really liked the quote at the beginning, its a really great hook. However, I think that in "After a few short years of an engineer", the 'of' may be replaced with an 'as'. Futhermore, when you are talking about his religious beliefs, you forgot to put and 'h' in his. Reply Options Unfold by Nathan B , 06 Mar 2008 14:46 Fold Kiefer 17 Mar 2008 21:33 Good biography. Maybe you could have text beside his picture as well so that your article dosn't have a large blank space. <a href="http://www.goldvk.com/Game.gw2_us.Guild Wars 2.gw2.Gold.Info.aspx">gw2 gold</a> Also, are one of your sources a journal article? If one is then my mistake, but you might want to use a journal article from the sites Mr. Laxon told us about. Reply Options Unfold by Kiefer , 17 Mar 2008 21:33 Fold Netheram 26 Mar 2008 02:23 Your biography is very concise and to the point, sticking closely to Cauchy's mathematical history and . Cheers! My only concerns have to do with grammar, but they can easily be remedied by an editor. Ex.: "Cauchy began an early education from his father and was the particular interest in Lagrange, a visitor to the Cauchy home." "Cauchy recieved an early education […] and Lagrange, a visitor to the Cauchy home, took a particular interest in the youth." Reply Options Unfold by Netheram , 26 Mar 2008 02:23 Fold Mr Laxon 07 Apr 2008 03:46 Cauchy was very influential. Cauchy limits rule  What is a holomorphic function? A little more explanation might be good. Reply Options Unfold by Mr Laxon , 07 Apr 2008 03:46 Add a New Comment Permanent Link Edit Delete link text ( function() function rgb2hex(rgb) { rgb = rgb.match(/^rgb\((\d ),\s*(\d ),\s*(\d )\)$/); function hex(x) { return ("0" parseInt(x).toString(16)).slice(-2); return hex(rgb[1]) hex(rgb[2]) hex(rgb[3]); } if (window.CHITIKA === undefined) window.CHITIKA = { 'units' : [] ; }; var $p = $j('.chitika-probe'); var colorSiteLink = rgb2hex($p.find('a').css('color')); var $el = $p; var colorBg; do colorBg = $el.css("backgroundColor"); $el = $el.parent(); while( $el.length > 0 if (!colorBg) colorBg = 'rgb(255,255,255)'; colorBg = rgb2hex(colorBg); var colorText = rgb2hex($p.find('span').css('color')); var unit = "publisher":"wikidot","width":468,"height":250,"sid":"below_content","color_site_link": colorSiteLink, "color_bg": colorBg, "color_text": colorText; var placement_id = window. <a href="http://www.goldvk.com/Game.gw2_us.Guild Wars 2.gw2.Gold.Info.aspx">guild wars 2 gold</a> CHITIKA. <a href="http://www.goldvk.com/Game.gw2_us.Guild Wars 2.gw2.Gold.Info.aspx">gw2 gold</a> units.length; window.CHITIKA.units.push(unit); document.write(' '); var s = document.createElement('script'); s.type = 'text/javascript'; s.src = '//cdn.chitika.net/getads.js'; try document.getElementsByTagName('head')[0].appendChild(s); catch(e) document.write(s.outerHTML); ()); xboter 2014
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