The Hellenic Navy (HN) (Greek: Πολεμικό Ναυτικό, Polemikó Naftikó, abbreviated ΠΝ) is the naval force of Greece, part of the Greek Armed Forces. The modern Greek navy has its roots in the naval forces of various Aegean Islands, which fought in the Greek War of Independence. During the periods of monarchy (1833–1924 and 1936–1973) it was known as the Royal Navy (Βασιλικόν Ναυτικόν, Vasilikón Naftikón, abbreviated ΒΝ).The total displacement of all the navy's vessels is approximately 150,000 tons.The motto of the Hellenic Navy is "Μέγα το της Θαλάσσης Κράτος" from Thucydides' account of Pericles' oration on the eve of the Peloponnesian War. This has been roughly translated as "Great is the country that controls the sea". The Hellenic Navy's emblem consists of an anchor in front of a crossed Christian cross and trident, with the cross symbolizing Greek Orthodoxy, and the trident symbolizing Poseidon, the god of the sea in Greek mythology. Pericles' words are written across the top of the emblem. "The navy, as it represents a necessary weapon for Greece, should only be created for war and aim to victory."...............The Hellenic Merchant Marine refers to the Merchant Marine of Greece, engaged in commerce and transportation of goods and services universally. It consists of the merchant vessels owned by Greek civilians, flying either the Greek flag or a flag of convenience. Greece is a maritime nation by tradition, as shipping is arguably the oldest form of occupation of the Greeks and a key element of Greek economic activity since the ancient times. Nowadays, Greece has the largest merchant fleet in the world, which is the second largest contributor to the national economy after tourism and forms the backbone of world shipping. The Greek fleet flies a variety of flags, however some Greek shipowners gradually return to Greece following the changes to the legislative framework governing their operations and the improvement of infrastructure.Blogger Tips and Tricks
This is a bilingual blog in English and / or Greek and you can translate any post to any language by pressing on the appropriate flag....Note that there is provided below a scrolling text with the 30 recent posts...Αυτό είναι ένα δίγλωσσο blog στα Αγγλικά η/και στα Ελληνικά και μπορείτε να μεταφράσετε οποιοδήποτε ποστ σε οποιαδήποτε γλώσσα κάνοντας κλικ στη σχετική σημαία. Σημειωτέον ότι παρακάτω παρέχεται και ένα κινούμενο κείμενο με τα 30 πρόσφατα ποστς....This is a bilingual blog in English and / or Greek and you can translate any post to any language by pressing on the appropriate flag....Note that there is provided below a scrolling text with the 30 recent posts...Αυτό είναι ένα δίγλωσσο blog στα Αγγλικά η/και στα Ελληνικά και μπορείτε να μεταφράσετε οποιοδήποτε ποστ σε οποιαδήποτε γλώσσα κάνοντας κλικ στη σχετική σημαία. Σημειωτέον ότι παρακάτω παρέχεται και ένα κινούμενο κείμενο με τα 30 πρόσφατα ποστς.........

Wednesday, August 11, 2010

The Antikythira Mechanism..[ 1624 ]

The Antikythira Mechanism, Project Overview





Front Gears & Dials

Copied frpm....www.antikythera-mechanism.gr/
 More than a hundred years ago an extraordinary mechanism was found by sponge divers at the bottom of the sea near the island of Antikythera. It astonished the whole international community of experts on the ancient world. Was it an astrolabe? Was it an orrery or an astronomical clock? Or something else?

For decades, scientific investigation failed to yield much light and relied more on imagination than the facts. However research over the last half century has begun to reveal its secrets. It dates from around the end of the 2nd century B.C. and is the most sophisticated mechanism known from the ancient world. Nothing as complex is known for the next thousand years. The Antikythera Mechanism is now understood to be dedicated to astronomical phenomena and operates as a complex mechanical "computer" which tracks the cycles of the Solar System.

Previous researchers have used the latest technologies available to them -such as x-ray analysis- to try to begin to unravel its complex mysteries. Now a new initiative is building on this previous work, using the very latest techniques available today. The Antikythera Mechanism Research Project is an international collaboration of academic researchers, supported by some of the world's best high-technology companies, which aims to completely reassess the function and significance of the Antikythera Mechanism.

The project is under the aegis of the Hellenic Ministry of Culture and was initially supported by a grant from the Leverhulme Trust, UK. More details bout subsequent funding are here. The project has received strong backing from the National Archaeological Museum in Athens, which is custodian of this unique artefact. Two of the Museum's senior staff, Head of Chemistry, Eleni Magou, and Archaeologist-museologist, Mary Zafeiropoulou, have co-ordinated the Museum's side of the project and are actively involved with the research.

One UK and two Greek universities are the core of the academic research group -the astronomer Mike Edmunds and the mathematician and filmmaker Tony Freeth (University of Cardiff), the astronomer John Seiradakis (University of Thessalonica), the astronomer Xenophon Moussas and the physicist and historian of science Yanis Bitsakis (University of Athens). And last, but not least, the philologist and palaeographer Agamemnon Tselikas (NBG Cultural Foundation).

During the first data-gathering phase in the autumn of 2005, the most innovative technologies were used to reveal unknown elements of the mechanism. This research was carried out by two world-class high technology companies, Hewlett Packard (US) and X-Tek Systems (UK). X-Tek's superb three-dimensional x-rays were imaged using software from the leading German company, Volume Graphics. Technical support was also provided by the University of Keele (UK). The whole process was filmed by Tony Freeth's Film and Television production company, Images First, for a forthcoming TV documentary.

During September 2005, three specialized scientists from Hewlett-Packard's Mobile and Media Systems Laboratory came to Athens with their innovative digital imaging system to examine the surface inscriptions and other features on the Antikythera Mechanism. The HP team, Tom Malzbender, Dan Gelb and Bill Ambrisco-brought with them a remarkable piece of specialist equipment: a Dome that surrounds the sample under examination and takes a series of still photos to analyze the three-dimensional structure of the surface. This enables astonishingly detailed examination of fine details such as faded and worn inscriptions. It has been a revelation for the research team. See here for this data.

During October 2005, another team of specialists from the cutting-edge company, X-Tek Systems, came to Athens. Led by the company's pioneering proprietor, Roger Hadland, the group of experts consisted of David Bate, Andrew Ramsey, Martin Allen, Alan Crawley and Peter Hockley. Their aim was to use the very latest x-ray technology to look at the internal structure of the mechanism with its complex and confusing gear trains. With them they brought the prototype of a very powerful new x-ray machine, the eight-tonne "Bladerunner". 

Originally designed to search for minute cracks in turbine blades, this machine gives astonishingly detailed three-dimensional x-rays, using the latest "microfocus" x-ray techniques. It has opened a remarkable window on microscopic internal details of inscriptions and gearing at a resolution better than a tenth of a millimeter. 

Inscriptions can now be read that have not been seen for more than two thousand years and this is helping to build a comprehensive picture of the functions of the Antikythera Mechanism. Browse here some of the initial images from the Blade Runner.
This is work-in-progress and results are emerging on a stable basis as the data is analyzed:
- At the autumn of 2006, the Antikythera Mechanism Research Project has organized a major conference in Athens to present their research findings. These results opened a new chapter in the understanding of this extraordinary mechanism. The conference coincided with the publication of the first results at the journal "Nature".
- In July 2008, new results were published in Nature. These were focused on the functions of Back Dials of the Mechanism.
- In July-August 2009, a major symposium was organized within the scope of the 23rd International Congress of History of Science and Technology. Members and collaborators of the research project and leading historians of science and technology discussed the position of the Antikythera Mechanism within the history of science, technology and ideas.

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