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Reinhold Rüdenberg
Reinhold Rudenberg (or Rüdenberg) was a German-American electrical engineer and inventor, credited with many innovations in the electric power and related fields. Aside from improvements in electric power equipment, especially large alternating current generators, among others were the electrostatic-lens electron microscope, carrier-current communications on power lines, a form of phased array radar, an explanation of power blackouts, preferred number series, and the number prefix "Giga-". Early life and education Reinhold Rudenberg was born in Hannover to a family of Jewish descent. His father Georg was a manufacturer, who operated a plant for preparing, cleaning feathers and down goods. His mother was a daughter of the Chief Rabbi of the county of Braunschweig. He attended the Leibniz University Hannover (then Technische Hochschule), and after receiving his electrical engineering degrees (Dipl. Ing.) and doctorate (Dr. Ing.), both in 1906, he worked for Professor Ludwig Prand ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leibniz University Hannover
Leibniz University Hannover (), also known as the University of Hannover, is a public university, public research university located in Hanover, Germany. Founded on 2 May 1831 as Higher Vocational School, the university has undergone six periods of renaming, its most recent in 2006. Leibniz University Hannover is a member of TU9, an association of the nine leading Institute of Technology, Institutes of Technology in Germany. It is also a member of the Conference of European Schools for Advanced Engineering Education and Research, a non-profit association of leading engineering universities in Europe. The university sponsors the German National Library of Science and Technology, the largest science and technology library in the world.Profile of the TIB at Leibniz University Hannoveonline (English) retrieved 26 May 2012 History The roots of the university begin in the Higher Vocational College/Polytechnic Institute (), founded on 2 May 1831. In 1879 the Higher Vocational Schoo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emil Wiechert
Emil Johann Wiechert (26 December 1861 – 19 March 1928) was a German physicist and geophysicist who made many contributions to both fields, including presenting the first verifiable model of a layered structure of the Earth and being among the first to discover the electron. He went on to become the world's first Professor of Geophysics at the University of Göttingen.Bormann, P. (Ed.). (2012). Dedication to the 150th birthday of Emil WIECHERT (1861-1928). In P. Bormann (Ed.), New Manual of Seismological Observatory Practice 2 (NMSOP 2) (pp. 1-2). Potsdam: Deutsches GeoForschungsZentrum GFZ. Early years Wiechert was born in Tilsit, Province of Prussia, the son of Johann and Emilie Wiechert. After his father died, his mother, Emilie, moved to Königsberg so that Emil could study at the University of Königsberg. Owing to financial difficulties, he took longer than normal to complete his education and was finally awarded a Ph.D. on 1 February 1889.Emil Wiechert (1861 – 1928) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lens (optics)
A lens is a transmissive optical device that focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements''), usually arranged along a common axis. Lenses are made from materials such as glass or plastic and are ground, polished, or molded to the required shape. A lens can focus light to form an image, unlike a prism, which refracts light without focusing. Devices that similarly focus or disperse waves and radiation other than visible light are also called "lenses", such as microwave lenses, electron lenses, acoustic lenses, or explosive lenses. Lenses are used in various imaging devices such as telescopes, binoculars, and cameras. They are also used as visual aids in glasses to correct defects of vision such as myopia and hypermetropia. History The word ''lens'' comes from , the Latin name of the lentil (a seed of a lentil pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Coil
An electromagnetic coil is an electrical conductor such as a wire in the shape of a coil (spiral or helix). Electromagnetic coils are used in electrical engineering, in applications where electric currents interact with magnetic fields, in devices such as electric motors, generators, inductors, electromagnets, transformers, sensor coils such as in medical MRI imaging machines. Either an electric current is passed through the wire of the coil to generate a magnetic field, or conversely, an external ''time-varying'' magnetic field through the interior of the coil generates an EMF (voltage) in the conductor. A current through any conductor creates a circular magnetic field around the conductor due to Ampere's law. The advantage of using the coil shape is that it increases the strength of the magnetic field produced by a given current. The magnetic fields generated by the separate turns of wire all pass through the center of the coil and add ( superpose) to produce a strong ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hans Busch
Hans Walter Hugo Busch (27 February 1884 in Jüchen, North Rhine-Westphalia, Germany – 16 February 1973 in Darmstadt, Hesse) was a German physicist. He was a pioneer of electron optics and laid the theoretical basis for the electron microscope. From 1904 to 1905 he studied physics in Strasbourg, from 1905 to 1906 in Berlin and from 1907 to 1911 physics and applied physics in Göttingen. He then was assistant for applied electrical engineering in Göttingen. He received his doctorate in 1911 from the University of Göttingen. In 1920 he habilitated from the same university and was then Privatdozent of physics and applied physics. In 1921 he was Privatdozent in Jena. In 1922 he became associate professor in Jena. In 1929 he became professor at the Technische Hochschule (TH) in Charlottenburg (now Technische Universität Berlin). In 1930 he became Professor in Electrical Engineering at the TH Darmstadt (now Technische Universität Darmstadt) and from 1933 to 1934 the rector of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Microscope
The optical microscope, also referred to as a light microscope, is a type of microscope that commonly uses visible light and a system of lenses to generate magnified images of small objects. Optical microscopes are the oldest design of microscope and were possibly invented in their present compound form in the 17th century. Basic optical microscopes can be very simple, although many complex designs aim to improve resolution and sample contrast. The object is placed on a stage and may be directly viewed through one or two eyepieces on the microscope. In high-power microscopes, both eyepieces typically show the same image, but with a stereo microscope, slightly different images are used to create a 3-D effect. A camera is typically used to capture the image (micrograph). The sample can be lit in a variety of ways. Transparent objects can be lit from below and solid objects can be lit with light coming through ( bright field) or around ( dark field) the objective lens. Polar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Virus
A virus is a submicroscopic infectious agent that replicates only inside the living Cell (biology), cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Viruses are found in almost every ecosystem on Earth and are the most numerous type of biological entity. Since Dmitri Ivanovsky's 1892 article describing a non-bacterial pathogen infecting tobacco plants and the discovery of the tobacco mosaic virus by Martinus Beijerinck in 1898, more than 16,000 of the millions of List of virus species, virus species have been described in detail. The study of viruses is known as virology, a subspeciality of microbiology. When infected, a host cell is often forced to rapidly produce thousands of copies of the original virus. When not inside an infected cell or in the process of infecting a cell, viruses exist in the form of independent viral particles, or ''virions'', consisting of (i) genetic material, i.e., long ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poliomyelitis
Poliomyelitis ( ), commonly shortened to polio, is an infectious disease caused by the poliovirus. Approximately 75% of cases are asymptomatic; mild symptoms which can occur include sore throat and fever; in a proportion of cases more severe symptoms develop such as headache, neck stiffness, and paresthesia. These symptoms usually pass within one or two weeks. A less common symptom is permanent paralysis, and possible death in extreme cases.. Years after recovery, post-polio syndrome may occur, with a slow development of muscle weakness similar to what the person had during the initial infection. Polio occurs naturally only in humans. It is highly infectious, and is spread from person to person either through fecal–oral transmission (e.g. poor hygiene, or by ingestion of food or water contaminated by human feces), or via the oral–oral route. Those who are infected may spread the disease for up to six weeks even if no symptoms are present. The disease may be diagnosed by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protective Relay
In electrical engineering, a protective relay is a relay device designed to trip a circuit breaker when a Electrical fault, fault is detected. The first protective relays were electromagnetic devices, relying on coils operating on moving parts to provide detection of abnormal operating conditions such as over-current, overvoltage, reverse electric power, power flow, over-frequency, and under-frequency. Microprocessor-based Solid-state electronics, solid-state digital protection relays now emulate the original devices, as well as providing types of protection and supervision impractical with electromechanical relays. Relay, Electromechanical relays provide only rudimentary indication of the location and origin of a fault. In many cases a single microprocessor relay provides functions that would take two or more electromechanical devices. By combining several functions in one case, numerical relays also save capital cost and maintenance cost over electromechanical relays. However, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siemens-Schuckertwerke
Siemens-Schuckert (or Siemens-Schuckertwerke) was a German electrical engineering company headquartered in Berlin, Erlangen and Nuremberg that was incorporated into the Siemens AG in 1966. Siemens Schuckert was founded in 1903 when Siemens & Halske acquired Schuckertwerke. Subsequently, Siemens & Halske specialized in communications engineering and Siemens-Schuckert in power engineering and pneumatic instrumentation. During World War I Siemens-Schuckert also produced aircraft. It took over manufacturing of the Protos vehicles in 1908. In World War II, the company had a factory producing aircraft and other parts at Monowitz near Auschwitz. There was a workers camp near the factory known as Bobrek concentration camp. The Siemens Schuckert logo consisted of an S with a smaller S superimposed on the middle with the smaller S rotated left by 45 degrees.Siemens used this as a theme for their logos with absorbed companies: Siemens & Halske's logo was a large S with a small superim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harvard University
Harvard University is a Private university, private Ivy League research university in Cambridge, Massachusetts, United States. Founded in 1636 and named for its first benefactor, the History of the Puritans in North America, Puritan clergyman John Harvard (clergyman), John Harvard, it is the oldest institution of higher learning in the United States. Its influence, wealth, and rankings have made it one of the most prestigious universities in the world. Harvard was founded and authorized by the Massachusetts General Court, the governing legislature of Colonial history of the United States, colonial-era Massachusetts Bay Colony. While never formally affiliated with any Religious denomination, denomination, Harvard trained Congregationalism in the United States, Congregational clergy until its curriculum and student body were gradually secularized in the 18th century. By the 19th century, Harvard emerged as the most prominent academic and cultural institution among the Boston B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
