Extractions: Essay # 014285 :: Rwanda Genocide The Rwanda Genocide In 1994 Rwanda was known for one of the worst genocides since the Holocaust. The very name is sketched into our histories consciousness as a place of evil and unimaginable pain. Between April and July 1994, more than 800,000 Tuts... Essay # 014295 :: Sacrifice Within The Israelite Religion The primary religious rituals of Israelite religion involved sacrifices and offerings. The ritual system within the Israelite cult evolved around gifts and offerings that were presented before Yahweh. In examining the book of Leviticus, the sacrifici... Essay # 014305 :: Saint Bernadette Australia is an island continent and is located southeast of Asia . Australia is the smallest continent in the world . Australia is made up of six states . The climate in Australia varies greatly : a hot season , wet season with rains falling ma... Essay # 014315 :: Salem Witch Trial Essay # 014325 :: Salt Marshes Oceanography Salt Marshes Salt marshes are coastal wetlands rich in marine life, which are covered by water at least once per month. They are found in the intertidal zones along low-energy coastlines, forming along the margins of estuaries, where fr...
Electromagnetismo - Monografias.com Translate this page Un matemático chino, shen kua (1.030-1.090) fue el primero que escribió acercadel uso de una aguja magnética para indicar direcciones, que fue el http://www.monografias.com/trabajos13/electmag/electmag.shtml
Extractions: Descargar Agregar a favoritos Recomendar Imprimir Electromagnetismo De magnete, G; A B C B. A A B. Al conectar el interruptor en el circuito de la bobina B A B B BA A v de la onda es: V = f = (3 X 10 Hz) X (10 m) = 3 X 10 m/s = 300 000 km/s igual que el valor predicho por Maxwell, o sea, la velocidad de la luz. ANTENAS El elemento que produce las ondas se llama antena emisora. En el caso anterior la antena es la varilla. f le corresponde una longitud de onda dada por ( v/f ), siendo la v Figura 8 OSWALDO SALAS NIEBLES email@example.com COLEGIO SALESIANO SAN ROQUE.- BARRANQUILLA Volver al inicio Volver arriba Política de Privacidad y Contenido Haga Publicidad en Monografias.com ... Contáctenos
Extractions: Some sounds have come to symbolize the thrust of a society. The relentless pulse of a railroad steam locomotive was associated with the westward movement of people and the settlement of the western United States. The blast of a factory whistle signaled growing industrialization. Today a symbol of the dynamism of most technologically advanced and developing nations might well be the whirring noise of the ubiquitous and indispensable electric motor. Many scientific discoveries have led to technological innovations which may have helped humanity to do a task better or faster. The electric motor, however, has altered our lives in fundamental ways. It has lent momentum to the accelerating rate of change and progress. It has enabled industry to become a mass producer of goods, and it has helped to raise average living standards. Today's modern standard of living could not be sustained and our technological society would collapse, if we could no longer use electric motors.
Admiral Zheng's Fleet The most definitive reference to a compass appears to be a book by shen kua (AD 103094)who describes rubbing a lodestone against a needle and floating it http://www.oceansonline.com/zheng.htm
Extractions: Our history of oceanography would not be complete without reference to the contributions that the Chinese have made to ocean exploration. While not as well-known as some of their other scientific and technological contributions, the Chinese own the distinction of assembling the largest fleet to ever sail on the ocean. Early Chinese maritime history is sketchy (or just not well known) but one of their first contributions was the invention of the magnetic compass. The first definitive reports that the Chinese were aware of magnetism date to 240 B.C. although some scholars have pointed out that houses built in the Shang dynasty (1766?-1123? B.C.) are aligned with magnetic north, indicating a possible earlier application of magnetism. Here's a blurb from Time magazine's Most Important Events of the Millennium page: IT WAS LITTLE MORE than a magnet floating in a bowl of water, but without the nautical compass the millennium's great voyages of discovery could never have occurred. First used in feng shui (the Taoist system of environmental design), compasses appeared in China in the 4th century B.C. Lodestone pointers were replaced by flat slivers of iron, and then by needles, which arrived in the 6th century A.D. But the first account of seagoing compasses doesn't come until 1117, from Zhu Yu's
Extractions: zJs=10 zJs=11 zJs=12 zJs=13 zc(5,'jsc',zJs,9999999,'') About China Online Home Essentials ... Daily News zau(256,152,145,'gob','http://z.about.com/5/ad/go.htm?gs='+gs,''); Arts Chinese Language Entertainment Geography ... Help zau(256,138,125,'el','http://z.about.com/0/ip/417/0.htm','');w(xb+xb); Subscribe to the About China Online newsletter. Search China Online Resources of Chinese inventions, including paper, compass, gunpowder, kite, printing, and more. Alphabetical Recent Chopsticks Chinese people have been using kuaizi as one of the main tableware for more than 3,000 years. Chinese Paper Invention Paper was invented by Cai Lun in 105 AD, which was one of the four great inventions by the Chinese. Who Invented It? When? Chinese Inventions Modern Chinese sometimes are surprised to realize that modern agriculture, shipping, astronomical observatories, decimal mathematics, paper money, umbrellas, wheelbarrows, multi-stage rockets, brandy and whiskey, the game of chess, and much more, all came from China. Compass Invention In China, Shen Kua, had already given the first accurate description of a magnetic needle and clearly mentioned the phenomenon of magnetic declination.
III. EL MAGNETISMO HASTA EL AÑO 1800 Translate this page Un matemático chino, shen kua (1030-1090) fue el primero que escribió acerca deluso de una aguja magnética para indicar direcciones, que fue el antecedente http://omega.ilce.edu.mx:3000/sites/ciencia/volumen3/ciencia3/112/htm/sec_5.htm
Extractions: E N EL caso del magnetismo, al igual que en el de la electricidad, desde tiempos remotos el hombre se dio cuenta de que el mineral magnetita o imán (un óxido de hierro) tenía la propiedad peculiar de atraer el hierro. Tanto Tales de Mileto como Platón y Sócrates escribieron acerca de este hecho. En el periodo comprendido entre los años 1000-1200 d.C. se hizo la primera aplicación práctica del imán. Un matemático chino, Shen Kua (1030-1090) fue el primero que escribió acerca del uso de una aguja magnética para indicar direcciones, que fue el antecedente de la brújula. Este instrumento se basa en el principio de que si se suspende un imán en forma de aguja, de tal manera que pueda girar libremente, uno de sus extremos siempre apuntará hacia el norte. Más tarde, después del año 1100, Chu Yu informó que la brújula se utilizaba también para la navegación entre Cantón y Sumatra. La primera mención europea acerca de la brújula fue dada por un inglés, Alexander Neckham (1157-1217). Hacia 1269 Petrus Peregrinus de Maricourt, un cruzado francés, hizo una descripción detallada de la brújula corno instrumento de navegación. En el año 1600 el inglés William Gilbert (1544-1603), médico de la reina Isabel I, publicó un famoso tratado
William Gilbert (1544 - 1603) Translate this page O matemático e inventor shen kua (1030-93) refere-se ao uso do ímã como indicadorde direção, enquanto Chu Yu, em 1100, relata seu emprego na arte da http://br.geocities.com/saladefisica9/biografias/gilbert.htm
Lopan Compass One of the earliest texts that describe a northsouth pointing deviseis the text of shen kua written in 1088. This was approximately http://www.fengshuiseminars.com/articles/lopan.html
Extractions: The origins in the development of the magnetic compass belonged to the world of imperial magicians and geomancers not scientists. In fact it was some time before the compass was used for navigation of the seas. To understand the development of the magnetic compass one must look to the context its original use. This lies in the ancient Chinese art of geomancy or Feng Shui (wind and water). Wind and water not only referring to the actual elements themselves but also the invisible energy of the magnetic directions. Of all forms of divination, geomancy was perhaps that which became most deeply rooted in Chinese culture throughout the traditional period. A wealth of technical terms was applied to the configurations of terrain connecting together in many varying ways the Yang and Yin, the dragon and tiger, the earth, planets and stars. The protection of a site from harmful influences was always a matter of great importance, and the achievement of a balance of Yang and Yin forces. Thus the background history of geomancy is of some importance for that of the magnetic compass itself.
Fotografía Estenopeica Translate this page una imagen en una pagoda. shen kua, más tarde, corrigió la explicaciónde la formación de la imagen. Yu Chao - Lung, En el sX http://www.terra.es/personal/chullora/estenope.htm
Extractions: La mayoría de nosotros tendemos a pensar que este sistema óptico es imprescindible, y que sin él no se puede hacer fotografía. Pero esto no es cierto, hay un tipo de fotografía en el que no existe este sistema óptico, es la llamada "Fotografía estenopeica". Jon Grepstad, Historia (recogido de Jon Grepstad) Primeras observaciones y experiencias Renacimiento y Post-renacimiento. Leonardo Da Vinci (1452-1519) describe la formación de imágenes estenopeicas en su "Codex atlanticus". En él describe la formación de imágenes del sol a través de orificios practicados en las paredes de una iglesia. Giovanni Battista della Porta (1538-1615), un científico napolitano, ha sido considerado el inventor de la cámara oscura por su descripción de una cámara oscura estenopeica en la primera edición de su "Magia Naturalis" (1558). Su descripción ha sido muy conocida, pero el no fué de ningún modo el inventor. La estenopeica es aparéntemente un dibujo en "De Radio Astronomica et Geometrica"(1545), de Gemma Frisius. Gemma Frisius, un astrónomo, utilizó un estenopo en una habitación oscura para estudiar el eclipse solar de 1544. El término cámara oscura fué acuñado por Johannes Kepler (1571-1630). En ese momento el término indicaba una habitación o una tienda con un orificio y una lente usados por los artistas para dibujar paisajes. La lente permitía obtener una imagen más brillante y enfocarla a cierta distancia. Este tipo de cámara es distinto del usado por Frisius, que no tenía lente. En la década de 1620, Kepler inventó una cámara oscura portatil. Estas cámaras, utilizadas como ayuda al dibujo, se encontraron pronto en diversas formas y tamaños.
Pinhole Photography shen kua later corrected his explanation of the image. Yu ChaoLung in thetenth century used model pagodas to make pinhole images on a screen. http://www.photo.net/pinhole/pinhole
Extractions: var subscriber_p=0, user_id=0; Sign in Search Gallery Learn ... Community By Jon Grepstad Pinhole photography is lensless photography. A tiny hole replaces the lens. Light passes through the hole; an image is formed in the camera. Pinhole cameras are used for fun, for art and for science. Designing and building the cameras are great fun. Making images with cameras you have made yourself is a great pleasure, too. But in serious photography the pinhole camera is just an imaging device with its advantages and limitations, special characteristics and potentials. By making the best of the camera's potential great images can be produced. Some of the images could not have been produced with a lens. Nautilus drawing , originally taken from a book published by Arthur Willey in 1900, the eye is the oval opening to the upper right. Early Observations and Experiments The basic optical principles of the pinhole are commented on in Chinese texts from the fifth century BC. Chinese writers had discovered by experiments that light travels in straight lines. The philosopher Mo Ti (later Mo Tsu In the western hemisphere Aristotle (fourth century BC) comments on pinhole image formation in his work Problems . In Book XV, 6, he asks: "Why is it that when the sun passes through quadri-laterals, as for instance in wickerwork, it does not produce a figure rectangular in shape but circular? [...]" In Book XV, 11, he asks further: "Why is it that an eclipse of the sun, if one looks at it through a sieve or through leaves, such as a plane-tree or other broadleaved tree, or if one joins the fingers of one hand over the fingers of the other, the rays are crescent-shaped where they reach the earth? Is it for the same reason as that when light shines through a rectangular peep-hole, it appears circular in the form of a cone? [...]" (Aristotle 1936:333,341). Aristotle found no satisfactory explanation to his observation; the problem remained unresolved until the 16th century (Hammond 1981:5).
Moldwin's Time Line Of Solar Terrestrial Physics Translated by HDP Lee, London William Heinemann, 1963). 1088, shen kua, Chineseencylopaedist gave first clear account of suspended magnetic compasses. http://measure.igpp.ucla.edu/solar-terrestrial-luminaries/timeline.html
Extractions: (Freeman Dyson, "The Scientist as Rebel," in Nature's Imagination - The Frontiers of Scientific Vision, edited by John Cornwell (Oxford University Press, New York, 1995) Version (This is a work in progress Bibliography (References and sources for pictures, popular science articles and books, and historical time-lines) Purpose of Page and Comments Layout description: the date link will take you to Wikipedia's timeline for that year. Clicking the photo will expand the thumbnail. The scientist's name link will take you to a biography. Journal Article Reference links will take you to an electronic copy of the paper (note that several journals require subscription to access the online paper). (# a broken photo link - or a photo other than a portrait - signifies that I am looking for a photo. If you have or know of one please contact me). 350 BC Aristotle Father of Western scientific thought including the place of the sun and Earth and the idea of an unblemished sun. Ideas would dominate scientific thought for the next 1800 years (though his writings were essentially lost to the west for most of that time). (Aristotle [ca 345 BC]
Www.comanducci.it/database/risultati.asp?Ricerca=SHEN%20KUA%20V.%20SHEN%20GUA www.comanducci.it/database/risultati.asp?Ricerca=SHEN%20GUA%20o%20Chen%20Koua%20o%20Shen%20Kua Feng Shui accessories Planet Pa Kua - deities PPST7 Kuan Kung antique gold finish 15cm £10.50, Tsai Shen Yeh - Wealth God. Alsoknown as Lu Hsing the Star God of Wealth. PPST21 Tsai Shen Yeh 9 x 8cm £6.50, http://www.comanducci.it/database/risultati.asp?Ricerca=SHEN KUA V. SHEN GUA
History Of Astronomy: Persons (S) shen kua (10311095) Short biography and references (MacTutor Hist.Math.); Very short biography. Shepard, Alan Bartlett, Jr. (b. 1923 http://www.astro.uni-bonn.de/~pbrosche/persons/pers_s.html
Extractions: Sabliere (18th century) Sacrobosco: see Johannes de Sacrobosco (c.1195-1256) Sagan, Carl Edward Saha, Meghnad (1893-1956) Saint Vincent, Gregorius [Gregory of Saint Vincent] (1584-1667) Salomonovich, Alexander (b. 1916) Salpeter, Edwin Ernest (b. 1924) Sandage, Allan Rex (b. 1926) Sands, Benjamin F. (1812-1883) Short biography and references From the Catholic Encyclopedia, 1913
ThinkQuest : Library : CultureQuest shen kua CultureChinese Area of Study Physical Science Century11 ContributionHis Dream pool essays of 1086 outlines the principles of erosion, uplift http://library.thinkquest.org/C008444/pages/library/info/asian.html
Star Picks A nice simple format based on the years climbing a double helix, we take a trip fromthe year 1000 with Omar Khayyam, Tseng KungLiang, and shen kua to (almost http://www.reactivereports.com/17/17_5.html
Extractions: http://www.timelinescience.org/ One thousand years of scientific thought, condensed, like so much soup, into a web site. But, there's nothing sloppy about this ladder of scientific history. A nice simple format based on the years climbing a double helix, we take a trip from the year 1000 with Omar Khayyam, Tseng Kung-Liang, and Shen Kua to (almost) the present day and the likes of the invention of the inkjet printer in 1976 and cloned sheep and pigs at the end of the millennium. ingenta http://www.ingenta.com/ ingenta provides a gateway for finding research papers quickly and easily, for free. If you want full text, then this is available gratuitously where a publisher has made that provision although much the document delivery services will take a slice from your budget. Most fields of scientific endeavour are searchable from agriculture and food sciences to social sciences, by way of chemistry, of course. Delights of Chemistry http://www.chem.leeds.ac.uk/delights/ This is a virtual version of one of those fantastic "flashes and bangs" lectures we used to get as students, at the end of the semester. There are forty chemistry demos, 120+ photos, and some "stunning" movies and animations. Put together in decent fashion by Leeds chemists Mike Hoyland, Vladimir Volkovich, and Daniel Ormsby.
Extractions: Galleria Photo Gallery ... Home During the early years of the second millennium, Arabic science proliferated, especially with regards to research in astronomy, optics, and vision. The Chinese investigations of optics also flourished for a time as they experimented with lenses, mirrors, and shadows, but stagnated after the 1200s. In medieval Europe, scholars strictly adhered to the teachings of the ancient Greek philosophers, particularly Aristotle, as well as those of the Church. Science was viewed as a process that required only observation of the natural world interpreted by rational thought and correct theology. Experimentation was not considered essential to understanding how the world works, at least not a world thought to lie at the center of a changeless universe. Nevertheless, this 600-year period did see significant breakthroughs in optics and science. The Greek notion that the eyes transmit light rays was finally discarded and the eyes were correctly understood to be light receivers. The first truly functional magnifying lenses were produced in the 1200s, and by the 1400s lenses were being used to make reading glasses. The Chinese had developed eyeglasses with colored lenses even earlier, but these apparently were used for ornamental purposes, rather than vision correction. By 1600, high quality lenses were being produced and used to make the first microscopes and telescopes. During the second half of the 1200s, as the Arab and Chinese sciences were fading, Europe began to emerge from its Dark Age. Robert Grosseteste, an English bishop (Bishop of Lincoln) and scholar, introduced Latin translations of Greek and Arabic philosophical and scientific writings to medieval Europe. Remarkably, he proposed that a theory could only be validated by testing its predictions with experimentationa substantial deviation from Aristotelian philosophy and the beginning of scientific method in Europe. His student, Roger Bacon, continued his advocacy of experimentation and tried, unsuccessfully, to get the Church to incorporate experimental methods into its educational system.
Extractions: Early 1000's A series of roads is built by Native Americans to connect towns in and around what is now Chaco Canyon, NM. Built by clearing rubble, the roads sometimes have paved surfaces and curbs. Some are 30 feet wide and often completely straight, sometimes scaling cliff faces with stairways cut into the rock. 1000 A.D. Inhabitants of Easter Island begin erecting stones. Heroic poem "Beowulf" is written in Old English. Christianity reaches Iceland and Greenland Spiritual center of Judaism switches from Mesopotamia to Spain Maya civilization in Yucatan Peninsula is at its climax. Leif Ericson, son of Eric the Red, reportedly discovers America (Nova Scotia) Indian mathematician, Sridhara recognizes the importance of the zero. Chinese perfect gunpowder invention, made of charcoal, sulfur, and potassium nitrate. "Click here for the story of Little Lizard" (1021)