Györfi László
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Előadó
Az előadás egy esettanulmányt mutat be, mely a Kárpát-medencét, ezen belül a mai Magyarország területét érintő Kr. e. 4-3. századi kelta népmozgalmakat vizsgálja, s ezen keresztül szemlélteti a történettudomány és a régészet viszonyát, illetve kapcsolatrendszerét.
The legendary event recounted by the historian Livius - Vae Victis - dramatising the attack of the Gauls in Rome demonstrates well the image of the ancient Romans had of the Celts: ruthless barbarians driven by the desire to rob and steal. However, modern archaeology has shown that the Celtic Migration cannot be explained by a lust for treasure. In 450-400 B.C. in certain parts of the Celtic world (e.g. in Champagne) overpopulation and a later cessation of the usage of cemeteries point towards a migration of the population. The expansion of the Celts can primarily be viewed as a peaceful colonisation. The findings at Monte Bibele show the symbiosis of the local Etruscan population with the Celts. In Northern Serbia we can observe the assimilation of local Illyrians with immigrant Celts, this is repeated on the Great Hungarian Plain where Scythian objects were found alongside Celtic ones (e.g. at Sajópetri). The evidence of ethnic and cultural integration and the development of an Eastern Celtic cultural coinage shows a number of regional characteristics and we can conclude that by 300-200 B.C the Carpathian basin had become a new centre in the Celtic world.
Az információtechnológia alapvető feladata az információ átvitele, tárolása során az információ tömörítése és védelme. A tömörítés lehet veszteségmentes, amikor az üzenetsorozatot úgy kódolják, hogy az üzenet egyértelműen reprodukálható legyen. Veszteséges tömörítés esetén nem követeljük meg a tökéletes reprodukciót. Az információ védelme jelentheti az sérülés elleni védelmet, továbbá az adatvédelmet - vagyis a titkosítást -, a hozzáférésvédelmet, illetve a hitelesítést - vagyis a manapság oly sokat emlegetett digitális aláírást. Az előadás az információelmélet egyik meglepő és fontos természettörvényét, a hibajavító kódolás elvi határait mutatja be.
Information theory consists of the theoretical limits of the economical and secure solutions of certain information technology tasks and the encoding rules approaching these limits. These tasks may involve the compression and protection of information during information transfer and storage. There are two types of compression. One is loss-free compression the other involves loss. Protection of information may mean protection against noisy information transmission (error correcting coding), data protection (encryption), access protection or authentication (digital signature). Of these information security tasks the lecture describes in detail error correcting coding. According to the law of error correcting coding, data transfer can both be economical and secure, i.e. there exists a maximum level of channel utilisation: channel capacity. The most important characteristic of information is that it is random; therefore the laws of information theory use and further develop the law of large numbers.
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Előadó
Az ideális világot kutató, platonikus tradíciókat ápoló Európával szemben az arabok inkább a természettudományok iránt érdeklődtek, azokat fejlesztették. Nem csoda hát, ha Európa kulturális és tudományos képe alapjában véve változott meg, amikor latinra fordították az arab tudományos műveket.
When the Arabs conquered the Eastern and the North African territories of the Roman Empire, they also acquired classical culture and sciences. After 632 A.D. further inroads were made into the Roman Empire, taking over the inheritance of the peoples of the former Greek provinces, which was then passed on to us, primarily, by the Arabs. While Europe was nurturing the Platonic tradition the Arabs cultivated the natural sciences. The scientific model of searching for causes and proof comes from Aristotle. Sciences in line with this model are known today as the axiomatic deductive sciences. Ibn Khaldoon's philosophy of history goes back to Aristotle, as do Bakhtishu's and Rabban's medical sciences. The Arabs passed on to us the study of humour and empirical observations by Galen as well as Dioscorides's tract on medical herbs. Ibn Sina's cosmology also combines Aristotelian traditions with Neo-Platonic teachings and the atomic theory of Maimonedes also goes back to Epicure. Educational institutions connected to mosques were the bases from which Arabic literature and linguistics were taught and exercised.