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

Saturday, February 1, 2014

Desert kites - 1


The Syrian Desert is an arid land of south-western Asia, extending from the northern Arabian Peninsula to the eastern Jordan, southern Syria, and western Iraq, largely covered by lava fields. Considered in the past as a barrier between Levant and Mesopotamia, it is now crossed by several routes and pipelines. This desert possesses two volcanic regions. One is the Jabal al-Druze, in the As-Suwayda Governorate. The other field is that of the Harrat Ash Shaam.

When we observe this desert from space, we discover that this harsh environment was probably quite populated in ancient times. We can conclude this fact from some huge stone structures, the "desert kites", that can be easily seen in the images recorded by satellites. These structures were firstly observed by pilots of the Royal Air Force in the 1920s, flying over the desert. These pilots named them "kites", because these lines reminded of kites used by children to play, but in fact they are huge hunting traps.

We usually imagine our ancestors, before they settle down, as people simply hunting and gathering for food, but this is not true. The "desert kites" are the remains of an ancient hunting technique based on stone-walled traps, the construction of which surely involved several people for long times. The desert kites were used to push large herds of animals into some enclosures, or, in the worse case, to fall off from steep cliff edges. The simplest structure of a desert kite has a triangular shape, consisting of two long, low walls built of stones and arranged in a V-shape, like a  funnel, ending as a corral. Hunters pushed the game between the walls, trapping then the animals into the end of the structure. It is usually considered that animals were slaughtered “en masse”.

Typically, a desert kite possesses two, three or more small circular enclosures on the edge of its corral. Some ancient rock art images show these hunting traps, depicting the role of the 'walls' of the kites. Let us note that these walls are low and then not able to stop any game. In fact, the walls are not walls at all: they are the basements, in the rocky harraat, where stick some poles and build a fence with branches. These structures create a visual effect as a barrier for the animals.



"Kite" rock-drawing from Jordan,  G.L. Harding: The Cairn of Hani, Antiquity 28,1954:pp 165-7
(2007-02-22) In 1951, Harding discovered a burial cairn with Safaitic inscriptions. On one of the stones was scratched a hunting scane.The cairn is located in the heart of the 'Kite' area,there is no doubt that the drawing depicts a scane of the gazelles being hunted in such a' Kite'.

References
23 June 2011,  http://arxiv.org/abs/1106.4665 , http://arxiv.org/pdf/1106.4665v1.pdf
February 2009, Khaybar Desert Kites, Vanja Janežic
alsahra.org/wp-content/uploads/2009/02/khaybar-desert-kites.pdf
http://www.megalithic.co.uk/article.php?sid=2146412866

Friday, December 27, 2013

Trundholm Sun Chariot and Langstrup Plate

Read please this post, very interesting

Les dues vides del Carro Solar de Trundholm, Publicat per Albert
títol del TREBALL DE FINAL DE GRAU,  carrera d'Humanitats  a la UNIVERSITAT POMPEU FABRA.
at http://alauniversitat.blogspot.it/2013/11/les-dues-vides-del-carro-solar-de.html
And also /news.discovery.com/history/archaeology/bronze-age-calendar-120330.htm



By Nationalmuseet, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=47971456

See also: http://arxiv.org/abs/1203.2512
Ancient bronze disks, decorations and calendars, Amelia Carolina Sparavigna
(12 Mar 2012) Recently, it was published that some ancient bronze disks could had been calendars, that is, that their decorations had this function. Here I am discussing an example, the disk of the Trundholm Sun Chariot, proposing a new interpretation of it, giving a calendar of 360 days. Some geometric diagrams concerning the decoration layout are also proposed. Comments: Ancient calendars, ancient time-keeping, Bronze Age, Trundholm Sun Chariot
Cite as: arXiv:1203.2512 [physics.pop-ph]

See also http://arxiv.org/abs/1203.4103
Number pi from the decoration of the Langstrup plate, Amelia Carolina Sparavigna
(19 Mar 2012), Studies of ancient bronze artifacts can be useful in understanding the progression of human knowledge of mathematics and geometry. Here I discuss the decoration composed by several circles and spirals of the Langstrup belt disk, an artifact of the Bronze Age found in Denmark. I am showing by measurements of diameters and distances of spirals, that the artist who made the decoration knew some approximations by rational numbers of the number pi, the dimensionless physical quantity representing the ratio of circumference to diameter. Comments: Ancient measurements of pi as ratio of circumference and diameters, giving rational numbers,
Cite as: arXiv:1203.4103 [physics.pop-ph]

Thursday, October 24, 2013

A literary experiment on Harry Potter and his social network

Literary works can be analyzed in the framework of the network theories, as proposed for instance by the Stanford Literary Laboratory, in some of their experiments. The plot of a play or a novel, can be displayed as a network of interacting characters, where the timeline of the plot is projected on a planar graph. We can discuss this approach and apply it to the first novel of the Harry Potter series written by J.K. Rowling, entitled Harry Potter and the Philosopher's Stone. Besides being an entertaining application for teaching networks, this approach can help in highlighting some features of the plot structure.

More details at:A.C. Sparavigna, On Social Networks in Plays and Novels, The International Journal of Sciences, Volume 3, Issue 10, 2013, Pages: 20-25
 DOI: 10.18483/ijSci.312
http://www.ijsciences.com/pub/article/312

Tuesday, September 3, 2013

Sea Silk (Bisso)

From Wikipedia - ...
China never managed to reach the Roman Empire directly in antiquity, although general Ban Chao sent Gan Ying as an envoy to "Daqin" in 97 AD. Gan Ying did not reach Daqin, he stopped at the coast of a large sea, because "sailor(s) of the Parthian west border" told him that the voyage to cross the sea might take a long time and be dangerous. Gan Ying left a detailed account of the Roman Empire, but it is generally considered to have been based on second hand information:
The Kingdom of Da Qin (the Roman Empire) is also called Lijian. As it is found to the west of the sea, it is also called the Kingdom of Haixi ("West of the Sea"). The territory extends for several thousands of li. It has more than four hundred walled towns. There are several tens of smaller dependent kingdoms. The walls of the towns are made of stone. They have established postal relays at intervals, which are all plastered and whitewashed. There are pines and cypresses, as well as trees and plants of all kinds.
- Gan Ying gives a very idealistic view of Roman governance which is likely the result of some story he was told while visiting the Persian Gulf in 97 AD. He also described, less fancifully, Roman products:
Their kings are not permanent. They select and appoint the most worthy man. If there are unexpected calamities in the kingdom, such as frequent extraordinary winds or rains, he is unceremoniously rejected and replaced. The one who has been dismissed quietly accepts his demotion, and is not angry. The people of this country are all tall and honest. They resemble the people of the Middle Kingdom and that is why this kingdom is called Da Qin. This country produces plenty of gold [and] silver, [and of] rare and precious [things] they have luminous jade, 'bright moon pearls,' Haiji rhinoceroses, coral, yellow amber, opaque glass, whitish chalcedony, red cinnabar, green gemstones, gold-thread embroideries, woven gold-threaded net, delicate polychrome silks painted with gold, and asbestos cloth.
They also have a fine cloth which some people say is made from the down of 'water sheep' [sea silk], but which is made, in fact, from the cocoons of wild silkworms (wild silk). They blend all sorts of fragrances, and by boiling the juice, make a compound perfume. [They have] all the precious and rare things that come from the various foreign kingdoms. They make gold and silver coins. Ten silver coins are worth one gold coin. They trade with Anxi [Parthia] and Tianzhu [North-western India] by sea. The profit margin is ten to one. . . . The king of this country always wanted to send envoys to the Han, but Anxi [Parthia], wishing to control the trade in multi-coloured Chinese silks, blocked the route to prevent [the Romans] getting through [to China].

Thursday, August 22, 2013

Moving sand dunes on Mars

Moving Sand Dunes on Mars, by Amelia Carolina Sparavigna, Department of Applied Science and Technology, Politecnico di Torino, Torino, Italy

Abstract: It was recently announced that the sand dunes on Mars can move. This important result was obtained by means of the High Resolution Imaging Science Experiment (HiRISE), the camera onboard the Mars Reconnaissance Orbiter. The images, recorded three years apart, of the dunes in the Nili Patera caldera show that they move. Here we compare an image HiRISE of 2007 with an image of 1999 recorded by the Mars Global Surveyor. Therefore, with the help of Gimp, the GNU image processing software to enhance the images, we can see and measure the motion of the dunes during a longer period of time.

A dune on Mars which is moving. In the Nili Patera caldera.
199 on the left, 2007 on the right


More details and article at:


Thursday, August 15, 2013

Peruvian dunes (Google Earth)



http://staff.polito.it/amelia.sparavigna/DUNE/

"Moving Dunes on the Google Earth" at http://arxiv.org/abs/1301.1290
(where I show how to use the time series of the Google Earth to estimate the motion of the barchans. I discuss also how to use reference points and adjust the Google images to have a "movie")

"A Study of Moving Sand Dunes by Means of Satellite Images"

Sunday, August 11, 2013

From Google Earth to Tatooine

Today (11 August 2013)  I found this article entitled "Star Wars home of Anakin Skywalker threatened by dune" http://www.bbc.co.uk/news/science-environment-23375344
It is told that "Sand dunes migrating over the Tunisian desert are poised to bury a famous Star Wars film set. The buildings of the fictional city Mos Espa featured in The Phantom Menace, "Episode I" of the Jedi saga. Sited on the planet Tatooine, this was the home of the young Anakin Skywalker ... Scientists have used the dwellings as a fixed geographic reference to measure the migration of giant wind-blown crescent-shaped dunes, or barchans. They have published details in the journal Geomorphology." The paper is in press, and you can see it at  http://www.sciencedirect.com/science/article/pii/S0169555X13003486
BBC continues "Ralph Lorenz, from Johns Hopkins University, ...  visited the Mos Espa site in 2009, and noted that part of a nearby set used in Star Wars Episode IV: A New Hope had already been overrun. Using satellite images of the site, they were able to determine the speed of dune movement, which is approaching the buildings once inhabited by such luminaries as Anakin, his slave owner Watto, and rival podracer Sebulba".
Before these "Dunes on the planet Tatooine",  on 4 January 2013 it was published  my "Moving Dunes on the Google Earth", as you can find at http://arxiv.org/abs/1301.1290, where I showed how to use the time series of the Google Earth to estimate the motion of the barchans. I used the barchans in Peru. I have also  discussed how to use reference points and adjust the Google images to have a "movie".
It seems that the authors of "Dunes on planet Tatooine: Observation of barchan migration at the Star Wars film set in Tunisia" do not know my "Moving dunes on the Google Earth" because my paper is not cited.
Therefore I cite myself!

And show you a "movie" of the barchan which is threatening Luke Skywalker's home.








Moving sand dunes on the Google Earth

"Moving dunes on the Google Earth" is my paper on arXiv, published 4 January 2013. It shows how using GH time series you can see the motion of dunes. Here an example.


To see a movie, please visit Moving sand dunes ... post

Sunday, July 14, 2013

Dharmadhatu



Dharmadhatuvagishvara Manjushri, gilded bronze, Nepal, 19th century
MAO, Museo d'Arte Orientale, Torino