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NCSX Modular Coils And Reference Plasma
The National Compact Stellarator Experiment, NCSX in short, was a magnetic fusion energy experiment based on the stellarator design being constructed at the Princeton Plasma Physics Laboratory (PPPL). NCSX was one of a number of new stellarator designs from the 1990s that arose after studies illustrated new geometries that offered better performance than the simpler machines of the 1950s and 1960s. Compared to the more common tokamak, these were much more difficult to design and build, but produced far more stable plasma, the main problem with successful fusion. The design proved to be too difficult to build, repeatedly running over its budget and timelines. The project was eventually cancelled on 22 May 2008, 0.04. ;Magnet coils: * 18 modular coils (6 each of types A, B, C) of wound copper wire, cooled with liquid nitrogen (LN2), * 18 toroidal coils, solid copper cooled with LN2, * 6 pairs of poloidal field coils, solid copper cooled with LN2, * 48 trim coils. csx.pppl.gov/ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NCSX Machine Desgin
The National Compact Stellarator Experiment, NCSX in short, was a magnetic fusion energy experiment based on the stellarator design being constructed at the Princeton Plasma Physics Laboratory (PPPL). NCSX was one of a number of new stellarator designs from the 1990s that arose after studies illustrated new geometries that offered better performance than the simpler machines of the 1950s and 1960s. Compared to the more common tokamak, these were much more difficult to design and build, but produced far more stable plasma, the main problem with successful fusion. The design proved to be too difficult to build, repeatedly running over its budget and timelines. The project was eventually cancelled on 22 May 2008, 0.04. ;Magnet coils: * 18 modular coils (6 each of types A, B, C) of wound copper wire, cooled with liquid nitrogen (LN2), * 18 toroidal coils, solid copper cooled with LN2, * 6 pairs of poloidal field coils, solid copper cooled with LN2, * 48 trim coils. csx.pppl.gov/Me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quasisymmetry
In magnetic confinement fusion, quasisymmetry (sometimes hyphenated as quasi-symmetry) is a type of continuous symmetry in the magnetic field strength of a stellarator. Quasisymmetry is desired, as Noether's theorem implies that there exists a conserved quantity in such cases. This conserved quantity ensures that particles stick to the flux surface, resulting in better confinement and neoclassical transport. It is currently unknown if it is mathematically possible to construct a quasi-symmetric magnetic field which upholds magnetohydrodynamic force balance, which is required for stability. There are stellarator designs which are very close to being quasisymmetric, and it is possible to find solutions by generalizing the magnetohydrodynamic force balance equation.{{Cite journal , last1=Rodríguez , first1=E. , last2=Bhattacharjee , first2=A. , date=January 2021 , title=Solving the problem of overdetermination of quasisymmetric equilibrium solutions by near-axis expansions. I. Genera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Department Of Energy
The United States Department of Energy (DOE) is an executive department of the U.S. federal government that oversees U.S. national energy policy and manages the research and development of nuclear power and nuclear weapons in the United States. The DOE oversees the U.S. nuclear weapons program, nuclear reactor production for the United States Navy, energy-related research, and domestic energy production and energy conservation. The DOE was created in 1977 in the aftermath of the 1973 oil crisis. It sponsors more physical science research than any other U.S. federal agency, the majority of which is conducted through its system of National Laboratories. The DOE also directs research in genomics, with the Human Genome Project originating from a DOE initiative. The department is headed by the Secretary of Energy, who reports directly to the president of the United States and is a member of the Cabinet. The current Secretary of Energy is Jennifer Granholm, who has served ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Demon (thought Experiment)
In thought experiments, philosophers and scientists occasionally imagine entities with special abilities as a way to pose tough intellectual challenges or highlight apparent paradoxes. Examples include: * Descartes’ malicious demon – Cartesian skepticism (also called methodological skepticism) advocates the doubting of all things that cannot be justified through logic. Descartes uses three arguments to cast doubt on our ability to know objectively: the dream argument, the deceiving God argument, and the malicious demon argument. Since our senses cannot put us in contact with external objects themselves, but only with our mental images of such objects, we can have no absolute certainty that anything exists in the external world. In the evil demon argument Descartes proposes an entity who is capable of deceiving us to such a degree that we have reason to doubt the totality of what our senses tell us. * Laplace's demon is a hypothetical all-knowing being who knows the precise lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photogrammetry
Photogrammetry is the science and technology of obtaining reliable information about physical objects and the environment through the process of recording, measuring and interpreting photographic images and patterns of electromagnetic radiant imagery and other phenomena. The term photogrammetry was coined by the Prussian architect Albrecht Meydenbauer, which appeared in his 1867 article "Die Photometrographie." There are many variants of photogrammetry. One example is the extraction of three-dimensional measurements from two-dimensional data (i.e. images); for example, the distance between two points that lie on a plane parallel to the photographic image plane can be determined by measuring their distance on the image, if the scale (map), scale of the image is known. Another is the extraction of accurate color ranges and values representing such quantities as albedo, specular reflection, Metallicity#Photometric colors, metallicity, or ambient occlusion from photographs of mater ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laser Tracker
{{Short description, Instruments that accurately measure large objects Laser trackers are instruments that accurately measure large objects by determining the positions of optical targets held against those objects. The accuracy of laser trackers is of the order of 0.025 mm over a distance of several metres. Some examples of laser tracker applications are to align aircraft wings during assembly and to align large machine tools. To take measurements the technician first sets up a laser tracker on a tripod with an unobstructed view of the object to be measured. The technician removes a target from the base of the laser tracker and carries it to the object to be measured, moving smoothly to allow the laser tracker to follow the movement of the target. The technician places the target against the object and triggers measurements to be taken at selected points, sometimes by a remote control device. Measurements can be imported into different types of software to plot the points or to c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metrology
Metrology is the scientific study of measurement. It establishes a common understanding of units, crucial in linking human activities. Modern metrology has its roots in the French Revolution's political motivation to standardise units in France when a length standard taken from a natural source was proposed. This led to the creation of the decimal-based metric system in 1795, establishing a set of standards for other types of measurements. Several other countries adopted the metric system between 1795 and 1875; to ensure conformity between the countries, the Bureau International des Poids et Mesures (BIPM) was established by the Metre Convention. This has evolved into the International System of Units (SI) as a result of a resolution at the 11th General Conference on Weights and Measures (CGPM) in 1960. Metrology is divided into three basic overlapping activities: * The definition of units of measurement * The realisation of these units of measurement in practice * Traceabi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NCSX Modular Coil In Process
The National Compact Stellarator Experiment, NCSX in short, was a magnetic fusion energy experiment based on the stellarator design being constructed at the Princeton Plasma Physics Laboratory (PPPL). NCSX was one of a number of new stellarator designs from the 1990s that arose after studies illustrated new geometries that offered better performance than the simpler machines of the 1950s and 1960s. Compared to the more common tokamak, these were much more difficult to design and build, but produced far more stable plasma, the main problem with successful fusion. The design proved to be too difficult to build, repeatedly running over its budget and timelines. The project was eventually cancelled on 22 May 2008, 0.04. ;Magnet coils: * 18 modular coils (6 each of types A, B, C) of wound copper wire, cooled with liquid nitrogen (LN2), * 18 toroidal coils, solid copper cooled with LN2, * 6 pairs of poloidal field coils, solid copper cooled with LN2, * 48 trim coils. csx.pppl.gov/Me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclotron
A cyclotron is a type of particle accelerator invented by Ernest O. Lawrence in 1929–1930 at the University of California, Berkeley, and patented in 1932. Lawrence, Ernest O. ''Method and apparatus for the acceleration of ions'', filed: January 26, 1932, granted: February 20, 1934 A cyclotron accelerates charged particles outwards from the center of a flat cylindrical vacuum chamber along a spiral path. The particles are held to a spiral trajectory by a static magnetic field and accelerated by a rapidly varying electric field. Lawrence was awarded the 1939 Nobel Prize in Physics for this invention. The cyclotron was the first "cyclical" accelerator. The primary accelerators before the development of the cyclotron were electrostatic accelerators, such as the Cockcroft–Walton accelerator and Van de Graaff generator. In these accelerators, particles would cross an accelerating electric field only once. Thus, the energy gained by the particles was limited by the maximum elec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electron
The electron ( or ) is a subatomic particle with a negative one elementary electric charge. Electrons belong to the first generation of the lepton particle family, and are generally thought to be elementary particles because they have no known components or substructure. The electron's mass is approximately 1/1836 that of the proton. Quantum mechanical properties of the electron include an intrinsic angular momentum ( spin) of a half-integer value, expressed in units of the reduced Planck constant, . Being fermions, no two electrons can occupy the same quantum state, in accordance with the Pauli exclusion principle. Like all elementary particles, electrons exhibit properties of both particles and waves: They can collide with other particles and can be diffracted like light. The wave properties of electrons are easier to observe with experiments than those of other particles like neutrons and protons because electrons have a lower mass and hence a longer de Broglie wavele ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microwave Oven
A microwave oven (commonly referred to as a microwave) is an electric oven that heats and cooks food by exposing it to electromagnetic radiation in the microwave frequency range. This induces polar molecules in the food to rotate and produce thermal energy in a process known as dielectric heating. Microwave ovens heat foods quickly and efficiently because excitation is fairly uniform in the outer of a homogeneous, high-water-content food item. The development of the cavity magnetron in the UK made possible the production of electromagnetic waves of a small enough wavelength (microwaves). American engineer Percy Spencer is generally credited with inventing the modern microwave oven after World War II from radar technology developed during the war. Named the "Radarange", it was first sold in 1946. Raytheon later licensed its patents for a home-use microwave oven that was introduced by Tappan in 1955, but it was still too large and expensive for general home use. Sharp Corpo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio-frequency
Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around to around . This is roughly between the upper limit of audio frequencies and the lower limit of infrared frequencies; these are the frequencies at which energy from an oscillating current can radiate off a conductor into space as radio waves. Different sources specify different upper and lower bounds for the frequency range. Electric current Electric currents that oscillate at radio frequencies (RF currents) have special properties not shared by direct current or lower audio frequency alternating current, such as the 50 or 60 Hz current used in electrical power distribution. * Energy from RF currents in conductors can radiate into space as electromagnetic waves ( radio waves). This is the basis of radio technology. * RF current does not penetrate deeply into electrical c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
