1,720,957 research outputs found
„Jön az üstökös!”: „The Comet is Coming!” / „Vine cometa!”
Get PDFThe comets are the most remarkable objects in the night sky. They appear suddenly and unexpectedly, their movement was unpredictable. Their tail looked like a fiery sword blazing across the night sky, the sky which was in meny ancient cultures the realm of the gods. So they have been regarded as messengers or punishments of the gods, omens of disasters. Old hungartian and trassylvanian chronicles will help us to understand how people of these regions percepted the comets along centuries. Until the science discovered the real nature of the comets and calculated comet orbits (Edmund Halley, 1705). Whether theese achievements of science spreaded around simple people and ridded them of the fear and dread of comets? To find out the answer we had turned up some newspapers two centuries later, when mankind was waiting for the predicted return of Halley comet in 1910.
Rezumat
Cometele sunt cele mai remarcabile obiecte pe cerul înstelat. Apar pe neașteptate și dintr-odată, mișcarea lor era imprevizibilă. Coada lor semăna cu o sabie înfierătoare, care strălucea pe cerul de noapte, cer care în cele mai multe culturi era tărâmul zeilor. Astfel cometele erau privite ca mesageri, ori pedepse ale zeilor, semne ale dezastrelor. Vechi cronici din Ungaria și Transilvania ne vor ajuta să înțelegem cum percepeau oamenii acestor meleaguri cometele de-a lungul secolelor. Până când savanții au descoperit fața adevărată a cometelor și le-au calculat mișcarea pe orbite (Edmund Halley, 1705). Oare aceste descoperiri ale științei s-au răspândit și printre oamenii simplii, și oare i-au scăpat de frica și spaima cometelor? Pentru a găsi răspunsul la această întrebare am răsfoit câteva ziare de două secole mai târziu, când omenirea aștepta cu suletul la gură reîntoarcerea cometei Halley din anul 1910
Erdély napórái: The Sundials of Transylvania / Cadrane solare din Transilvania
Get PDFThe sundial is the oldest device for measuring time. It was in use in Transilvania also, from the middle age, till today. After learning how can we recognise if a sundia l works exactly or not, the artricle makes a survey of the Transilvanian sundials: how many are, what kind they are, where can we find them, how exactly does they work.
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Cadranul solar este cel mai vechi instrument pentru măsurarea timpului. A fost folosit și în Transilvania, încă din evul mediu și până azi. După ce ne arată cum ne putem da seama, dacă un cadran solar funcționează corect sau nu, articolul de față trece în revistă cadranele solare din Transilvania: câte sunt, cel fel de tipuri, unde se găsesc, și cât de precis funcționează ele
Változó számjegyeink: Our changing numerals / Cifrele noastre schimbătoare
Get PDFWe use numbers daily, not only mathematicians, but everybody. We have been using them so much that we have forgotten what a big discovery numerals have been for humanity. Some people consider that this was the biggest discovery of humanity for the last 2000 years.
Roman numerals have spread throughout Europe because of the Roman empire, for almost one and half millennia. But it was very difficult to perform calculations with these early numerals, people used the abacus instead. When Hungarians came into Europe (896 A.D.), they had their own runic writing. But when St.Stephan I. converted Hungarians to Christianity (about 1000 A.D.), they began to use the Roman numerals.
Today we use the indo-arabic numerals. These were introduced into Europe by Fibonacci (by 1200 A.D.), because it was much easier to do calculations with these ones, than with the roman numerals. It took about 2-300 years before Europe became convinced of the usefulness of indo-arabic numerals. From where, how and when did these numerals spread in Transylvania? This article aims to answer these questions, by examining old books and paintings, coins, old churches, church bells and baptismal fonts.
Rezumat
Astăzi folosim cifrele zilnic, nu numai matematicienii, ci cu toții. Le folosim atât de des, încât am și uitat ce mare descoperire au fost cifrele pentru omenire. Unii consideră că cifrele au fost cea mai mare invenție a omenirii din ultimele două milenii.
Cifrele romane s-au răspândit în întreaga Europă datorită Imperiului Roman, pentru aproape un mileniu și jumătate. Dar era foarte greu să se facă calcule cu aceste cifre, se folosea de obicei abacul pentru efectuarea operațiilor matematice. Când maghiarii au venit în Europa (anul 896), au avut sistemul propriu de cifre runice. Dar când regele Stefan I. și-a convertit poporul la creștinism (aproximativ 1000 d. Hr.), au început să folosească și ei cifrele romane.
Azi folosim cifrele indo-arabe. Acestea au fost introduse de Fibonacci (prin anul 1200), pentru că a fost mult mai ușor să se facă calcule cu ele. Totuși au trebuit 2-3 secole, ca europenii să se convingă de utilitatea lor. De unde, când și cum au pătruns aceste cifre în Transilvani. Acest articol își propune să găsească răspunsurile la aceste întrebări, examinînd picturi și cărți vechi, monede vechi, biserici vechi și clopotele lor, cristelnițe de botez.
Kivonat
Naponta használjuk a számokat, nemcsak matematikusok, hanem mindenki. Annyira megszoktuk, őket, hogy már el is felejtettük, mekkora találmány volt ez annak idején az emberiség számára. Vannak akik azt állítják, hogy a számjegyek használata az utóbbi 2000 év legnagyobb találmánya.
A római számjegyek a Római Birodalomnak köszönhetően terjedtek el egész Európában, és majdnem másfél évezreden keresztül egyeduralkodók voltak. De nagyon nehéz volt matematikai műveleteket végezni velük, erre inkább az abakuszt használták. Amikor a honfoglaló magyarok Európába érkeztek (896), saját rovásírásos számjegyeik voltak. De amikor Szent István áttérítette népét a keresztény hitre (1000 körül), a római számjegyeket kezdték használni.
Ma a hindu-arab számjegyeket használjuk. Ezeket Fibonacci vezette be (1200 körül), ugyanis sokkal könnyebb volt matematikai műveleteket végezni velük. Mégis 2-3 századra volt szükség, hogy az európaiak meggyőződjenek e számjegyek előnyeiről. Honnan, mikor, és hogyan kerültek be Erdélybe a ma is használt számjegyeink? Erre keressük a választ régi könyvekben, festményeken, régi pénzeken, templomokban, harangokon és keresztelő medencéken
AC kontra DC – Az erdélyi villanyvilágítás története 1900-ig: AC vs DC – The history of electric light in Transylvania until 1900
Get PDFFIAT LUX! In the legends of most cultures just a God could bring the first light in the creation of the World. Today anyone can turn on a light everywhere he wants. How did we get here, how did we become creators of light? This road passed through three big steps, which we call today the technical revolutions: I. The energy of nature (water, wind); II. The energy of steam; III. The energy of electricity. The story of this last kind of energy, used for the light, begun in the XIX-th century.
Kivonat
FIAT LUX! A legtöbb kultúra teremtésmítoszaiban a legelején isteni erőre volt szükség, hogy fény legyen. Ma bárki felkapcsol egy kapcsolót, vagy megnyom egy gombot, máris fény van ott, ahol akarja. Hogyan jutottunk el idáig, hogyan tettünk szert a világítás tudására? Három nagy lépcsőfokon vitt át az út, amit ma ipari forradalomnak neveznek: I: A természet energiái (víz, szél); II: A gőz energiája; III. A villamosság energiája. Ez utóbbinak a szerepe a világításban a XIX. században kezdődött
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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