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Benvenuti in queste pagine dedicate a scienza, storia ed arte. Amelia Carolina Sparavigna, Torino

Wednesday, April 20, 2011

Rogue Waves

"The storm was nothing special. Its waves rocked the Norwegian Dawn just enough so that bartenders on the cruise ship turned to the usual palliative — free drinks.
Then, off the coast of Georgia, early on Saturday, April 16, 2005, a giant, seven-story wave appeared out of nowhere. It crashed into the bow, sent deck chairs flying, smashed windows, raced as high as the 10th deck, flooded 62 cabins, injured 4 passengers and sowed widespread fear and panic."
From
"Rogue Giants at Sea", by W.J. Broad
http://www.nytimes.com/2006/07/11/science/11wave.html?8dpc

Tuesday, April 19, 2011

World Wide Words: Action at a distance

"It first appeared in English in the word telescope. This was a usage adapted from Galileo’s Italian word telescopi for his new device, which he seems to have first used in 1611; two years later, Kepler employed the modern Latin telescopium. Galileo and Kepler apparently tried out a series of other names before settling on telescope, including perspicillum, conspicillum, specillum, and penicillium; if they had decided to use one of the others, it is very possible that we should now not have all these words starting in tele–."
World Wide Words: Action at a distance

Recovering the raised fields - Peru

Google Maps give beautiful pictures of the Earth. We have seen and shown in several posts that the satellite eye is able to display in great detail the archaeological remains and ruins. Let me show you here three images of some raised fields near the Lake Titicaca. These waru-warus (raised fields in Aymara language) are near Caritamaya.




According to a private communication (ConNuestroPeru), the archaeologists
are recovering some waru-warus having circular and radial shapes.

In fact, several waru-warus create geoglyphs featuring animals. 



The "raised fields" are earthworks separated by canals. This is an ancient agricultural technique used by Andean people starting from the first millennium BC. Each raised field is approximately 10 meters large and more than one hundred long. 

More on waru-waru
 arXiv:1009.4602 [pdfGeoglyphs of Titicaca as an ancient example of graphic design, Amelia Carolina Sparavigna
 arXiv:1009.2231 [pdfSymbolic landforms created by ancient earthworks near Lake Titicaca, Amelia Carolina Sparavigna


Monday, April 18, 2011

Moth-Eye Structures for Broadband Antireflection


Appl. Phys. Express 3 (2010) 102602 (3 pages)  |Previous Article| |Next Article|  |Table of Contents|
|Full Text PDF: FREE (763K)|

Hybrid Moth-Eye Structures for Enhanced Broadband Antireflection Characteristics


The authors are proposing hybrid moth-eye structures to have high antireflection propoerties. These structures can be applied to solar cells for high light -to-electricity cinversione efficiency



URL: http://apex.jsap.jp/link?APEX/3/102602/
DOI: 10.1143/APEX.3.102602

Moth eyes for solar cells

"Photovoltaics, which convert sunlight into electricity, have long been touted as one of the most promising solutions to our energy needs. Unfortunately, today's devices reflect a lot of solar energy as heat, which means that solar power is currently not as cheap as other forms of energy. Now, however, researchers in the Netherlands have developed an anti-reflective coating based on the nanostructure of a moth’s eyes, which could reduce the reflection from photovoltaic cells and thereby make them more efficient"
Moth eyes inspire more efficient solar cell - physicsworld.com

The trash vortex

"The trash vortex is an area the size of Texas in the North Pacific in which an estimated six kilos of plastic for every kilo of natural plankton, along with other slow degrading garbage, swirls slowly around like a clock, choked with dead fish, marine mammals, and birds who get snared. Some plastics in the gyre will not break down in the lifetimes of the grandchildren of the people who threw them away."
The trash vortex | Greenpeace International
"Il Pacific Trash Vortex, noto anche come Grande chiazza di immondizia del Pacifico (Great Pacific Garbage Patch), è un enorme accumulo di spazzatura galleggiante (composto soprattutto da plastica) situato nell'Oceano Pacifico, approssimativamente fra il 135º e il 155º meridiano Ovest e fra il 35º e il 42º parallelo Nord. La sua estensione non è nota con precisione: le stime vanno da 700.000 km² fino a più di 10 milioni di km² ... ovvero tra lo 0,41% e il 5,6% dell'Oceano Pacifico. ... L'accumulo si è formato a partire dagli anni cinquanta, a causa dell'azione della corrente oceanica chiamata Vortice subtropicale del Nord Pacifico (North Pacific Subtropical Gyre), dotata di un particolare movimento a spirale in senso orario, che permette ai rifiuti galleggianti di aggregarsi fra di loro.
http://it.wikipedia.org/wiki/Pacific_Trash_Vortex

Cotton on World Wide Words

Interessante la discussion sul "cotton on".
World Wide Words E-magazine: 16 Apr 2011
Il termine "cotonato" lo usamo per i capelli, mentre in Inglese si parla di "big hair"

Dharmacakra

"The Dharmacakra symbol is represented as a chariot wheel (Sanskrit cakram) with eight or more spokes. It is one of the oldest known Buddhist symbols found in Indian art, appearing with the first surviving post-Harappan Indian iconography in the time of the Buddhist king Aśoka. The Dharmacakra has been used by all Buddhist nations as a symbol ever since. In its simplest form, the Dharmacakra is recognized globally as a symbol for Buddhism." According Wiki http://en.wikipedia.org/wiki/Dharmacakra

Kongo Rikishi come Ercole

"Kongōrikishi are an interesting case of the possible transmission of the image of the Greek hero Heracles to East Asia along the Silk Road. Heracles was used in Greco-Buddhist art to represent Vajrapani, the protector of the Buddha, and his representation was then used in China and Japan to depict the protector gods of Buddhist temples. This transmission is part of the wider Greco-Buddhist syncretic phenomenon, where Buddhism interacted with the Hellenistic culture of Central Asia from the 4th century BC to the 4th century AD.*"
According to Wiki http://en.wikipedia.org/wiki/Shukongoshin
* "The origin of the image of Vajrapani should be explained. This deity is the protector and guide of the Buddha Sakyamuni. His image was modeled after that of Hercules. (...) The Gandharan Vajrapani was transformed in Central Asia and China and afterwards transmitted to Japan, where it exerted stylistic influences on the wrestler-like statues of the Guardian Deities (Nio)." (Katsumi Tanabe, "Alexander the Great, East-West cultural contacts from Greece to Japan", p23)