Whenever there is dissymmetry of information, whichever party has access to more information holds an upper hand over the less-informed party.
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For example, a random mixture of sand in zero gravity has no dissymmetry (it is isotropic). Introduce a gravitational field, and there is a dissymmetry because of the direction of the field. Then the sand grains can 'self-sort' with the density increasing with depth. But this new arrangement, with the directional arrangement of sand grains, actually reflects the dissymmetry of the gravitational field that causes the separation.
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3, no. 6, .Joseph Gal: Louis Pasteur, Language, and Molecular Chirality. I. Background and Dissymmetry, Chirality 23 (2011) 1−16.
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Ludus Tonalis consists of 25 movements:Bruhn, Siglind (1996). Symmetry and dissymmetry in Paul Hindemith's Ludus Tonalis, Symmetry: Culture and Science, vol. 7, no. 2, 116–132.
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He also discovered that ferromagnetic substances exhibited a critical temperature transition, above which the substances lost their ferromagnetic behavior. This is now known as the Curie temperature. The Curie temperature is used to study plate tectonics, treat hypothermia, measure caffeine, and to understand extraterrestrial magnetic fields. Pierre Curie formulated what is now known as the Curie Dissymmetry Principle: a physical effect cannot have a dissymmetry absent from its efficient cause.
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Far from the notion that teaching can be a matter of sharing or of maieutic, Levinas asserts the total dissymmetry of the relationship and the transcendence and complete otherness of the teacher.
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Whittle, Richard. "The Next X-Plane" Air & Space/Smithsonian, October 2015. Accessed: 26 September 2015. A helicopter with a conventional rotor layout has a theoretical top speed of , after which it suffers from dissymmetry of lift.
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The opposite torques from the rotors cancel each other out. Rotational maneuvering, yaw control, is accomplished by increasing the collective pitch of one rotor and decreasing the collective pitch on the other. This causes a controlled dissymmetry of torque.
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Dissymmetry is countered by "blade flapping": rotor blades are designed to flap: the advancing blade flaps up and develops a smaller angle of attack due to a change in relative wind vectors, thus producing less lift than a rigid blade would. Conversely, the retreating blade flaps down, develops a higher angle of attack due to a change in relative wind vectors, and generates more lift. Dissymmetry of lift is also countered by cyclic feathering, i.e. the variation in blade pitch arising from delta-three coupling of blade motions, or the forward input of cyclic during blowback.
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Circularly Polarized Luminescence Spectroscopy (CPL) Capable of measuring dissymmetry factors of even weakly luminescent materials to within a reported error as small as 10−6, the home-built CPL spectrometer created and used by the Bernhard lab is more sensitive than any previously demonstrated CPL spectrometer. In addition, it was shown that CPL dissymmetry factors can be predicted computationally over a diverse sampling of known luminophore architectures, validating a new and facile tool for directing synthetic efforts in the search for anisotropic emitters. Artificial Photosynthesis Efforts in this field have focused on solution-based water photolysis. Breaking the problem into smaller components, the Bernhard lab has distinguished its efforts in photosensitization , water photoreduction catalysis , and water oxidation catalysis .
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When dissymmetry causes the retreating blade to experience less airflow than required to maintain lift, a condition called retreating blade stall can occur. This causes the helicopter to roll to the retreating side and pitch up. This situation, when not immediately recognized can cause a severe loss of aircraft controllability.
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It is surrounded by grassy areas and plants separating the courtyard in symmetric areas, giving a perspective view of the main building to the arriving visitor. The main building follows a Louis XIII architectural style. Following this architecture trends, the château shows a very typical dissymmetry, unique to the Louis XIII style.
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The blades are allowed to flap, feather, and lead or lag independently of each other. The horizontal hinge, called the flapping hinge, allows the blade to move up and down. This movement is called flapping and is designed to compensate for dissymmetry of lift. The flapping hinge may be located at varying distances from the rotor hub, and there may be more than one hinge.
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Johnson HT, p. 325 Varying the rotor speed may induce severe vibrations at specific resonance frequencies. Contra-rotating rotors like on Sikorsky X2 solve the problem of lift dissymmetry by having both left and right sides provide near equal lift with less flapping. The X2 deals with the compressibility issue by reducing its rotor speed from 446 to 360 RPM to keep the advancing blade tip below the sound barrier when going above 200 knots.
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Retrieved: 19 February 2012. Normally a helicopter or gyrocopter cannot fly forward at the same speed as or faster than its rotor tip speed. This is because the low airspeed of the retreating rotor blade would cause retreating blade stall, whilst the advancing rotor blade would be traveling at twice the speed of the aircraft, producing uncontrollable flight due to dissymmetry of lift. However, with the CarterCopter, the fixed wings provide the lift required to remain aloft.
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South Yemen (formerly the People's Democratic Republic of Yemen) made polygamy legal with a new Family Code in 1992. In Algeria, the leftist secularist FLN government made Friday an official holy day in 1976. The family law of 1984 "re-introduced some sharia elements" such as Quranic dissymmetry between men and women, and the official policy of Arabisation led to a de facto Islamisation of education. In secular Turkey, religious teaching in schools was made compulsory in 1983.
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Brand implementation emerged as a discipline in the 1990s when brand owners recognized the need for consistency across branded estates. Traditionally, brand implementation was handled by various parties, including shop-fitters, interior designers and sign companies. Lack of centralized project management led to inconsistencies, while information dissymmetry meant suppliers had too much control over brand issues. Brand implementation was consequently coined as an umbrella term for all aspects of the application and maintenance of physical brand assets.
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A Ka-32 coaxial rotor animation Dissymmetry of lift is an aerodynamic phenomenon caused by the rotation of a helicopter's rotors in forward flight. Rotor blades provide lift proportional to the amount of air flowing over them. When viewed from above, the rotor blades move in the direction of flight for half of the rotation (advancing half), and then move in the opposite direction for the remainder of the rotation (retreating half). A rotor blade produces more lift in the advancing half.
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Flap back or blowback is a phenomenon affecting the rotor of a helicopter as it overcomes dissymmetry of lift through flapping. In forward flight, rotor blades experience more lift as they rotate forward. This increased lift is a result of an increased relative speed causing the blade to flap up and decrease its angle of attack. As the blade continues to rotate, it achieves its maximum upflapping displacement over the nose of the aircraft and maximum downflapping displacement over the tail.
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Since the rotor is unloaded, the aerodynamic forces on the rotor are very minor. This means that a CarterCopter can theoretically fly much faster than the tip speed of the rotor. The rotors would still experience flapping as they rotate due to dissymmetry of lift between the two sides of the vehicle, but Carter Aviation claims this is manageable. The claimed theoretical maximum speed of a CarterCopter type aircraft is around 500 mph (800 km/h),PRESS RELEASE, June 11, 1999 , Carter Aviation Technologies.
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Note that variation in distribution is observed within individuals, so abnormalities of this characteristic likely play a significant role in all psychological illnesses. Individual alterations are produced by differences within glutamatergic pathways within the limbic system, which are also implicated in other psychotic syndromes. Among the alterations of both synaptic and global structure, the most significant abnormalities are observed in the uncinate fasciculus and the cingulate cortex. The combination of these creates a profound dissymmetry of prefrontal inhibitory signaling, shifted positively towards the dominant side.
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With De la Cierva's autogyro, the rotor was drawn through the air by means of a conventional propeller, with the result that the rotor generated sufficient lift to sustain level flight, climb and descent. Before this could be satisfactorily achieved, De la Cierva experienced several failures primarily associated with the unbalanced rolling movement generated when attempting take-off, due to dissymmetry of lift between the advancing and retreating blades. This major difficulty was resolved by the introduction of the flapping hinge. In 1923, De la Cierva's first successful autogyro was flown in Spain by Lt. Gomez Spencer.
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Kamov Ka-50 of the Russian Air Force, with coaxial rotors Coaxial rotors are a pair of rotors mounted one above the other on the same shaft and turning in opposite directions. The advantage of the coaxial rotor is that, in forward flight, the lift provided by the advancing halves of each rotor compensates for the retreating half of the other, eliminating one of the key effects of dissymmetry of lift: retreating blade stall. However, other design considerations plague coaxial rotors. There is an increased mechanical complexity of the rotor system because it requires linkages and swashplates for two rotor systems.
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The entrance astonishes by its dissymmetry and the surprising presence of an enormous tower and a house. The wing offers a more homogeneous style but this unity is only on the surface and disguises several rebuildings. The chateau was in the 16th and 17th centuries by the family of Estampes. The castle of 12th century which existed on this site, was demolished and construction of its replacement began in 1520, albeit very slowly.. Louis of Estampes, governor and baillif of Blois, undertook the building of the large round tower at the end of the entrance wing.
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Because the advancing blade has higher airspeed than the retreating blade and generates a dissymmetry of lift, rotor blades are designed to "flap" – lift and twist in such a way that the advancing blade flaps up and develops a smaller angle of attack. Conversely, the retreating blade flaps down, develops a higher angle of attack, and generates more lift. At high speeds, the force on the rotors is such that they "flap" excessively, and the retreating blade can reach too high an angle and stall. For this reason, the maximum safe forward airspeed of a helicopter is given a design rating called VNE, velocity, never exceed.
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So a rotor blade is said to be an aysmmetric generator of lift, because of the difference in lift generated along its length. Helicopter manufacturers try to reduce this differential effect (that is, aim for more equality of lift along the blade length). This has two main aspects: # tapering a blade toward its tip, which reduces its surface area, in turn reducing its lift; # twisting the blade (commonly called geometric twist) so that the blade root near the hub presents a higher angle-of-attack, thus higher lift. When the helicopter is travelling forwards with respect to the atmosphere, a further phenomenon comes into play, dissymmetry of lift.
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1, C.2, and C.3) were unstable because of aerodynamic and structural deficiencies in their rotors. His fourth design, the C.4, made the first documented flight of an autogyro on 17 January 1923, piloted by Alejandro Gomez Spencer at Cuatro Vientos airfield in Madrid, Spain (9 January according to Cierva). De la Cierva had fitted the rotor of the C.4 with flapping hinges to attach each rotor blade to the hub. The flapping hinges allowed each rotor blade to flap, or move up and down, to compensate for dissymmetry of lift, the difference in lift produced between the right and left sides of the rotor as the autogyro moves forward.
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In 1815 the French physicist Jean-Baptiste Biot showed that certain chemicals could rotate the plane of a beam of polarised light, a property called optical activity. The nature of this property remained a mystery until 1848, when Louis Pasteur proposed that it had a molecular basis originating from some form of "dissymmetry", with the term chirality being coined by Lord Kelvin a year later. The origin of chirality itself was finally described in 1874, when Jacobus Henricus van 't Hoff and Joseph Le Bel independently proposed the tetrahedral geometry of carbon.van 't Hoff, J.H. (1874) "Sur les formules de structure dans l'espace" (On structural formulas in space), Archives Néerlandaises des Sciences Exactes et Naturelles, 9 : 445–454.
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On a helicopter this would cause massive lift dissymmetry and insoluble control issues but the fixed wings keep the aircraft in the air and stable. The low rotation speed and flat feathering of the rotor means that it causes little drag, and the company claims that the aircraft would be potentially able to leverage the advantages of fixed wings as well as gyrocopters, giving almost all the capabilities of helicopters (except hovering) but with a relatively simple mechanical system. Carter Aviation also claims the system is safer than a typical fixed-wing aircraft, and others have remarked that the design is much safer, much less complex and less expensive than a helicopter, a tilt-rotor or the Boeing X-50 Dragonfly Canard Rotor/Wing.SAFER by DESIGN , Press Release, July 2009, Carter Aviation Technologies.
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As a blade moves toward the direction of flight, the forward motion of the aircraft increases the speed of the air flowing around the blade until it reaches a maximum when the blade is perpendicular to the relative wind. At the same time, a rotor blade in the retreating half produces less lift. As a blade moves away from the direction of flight, the speed of the airflow over the rotor blade is reduced by an amount equal to the forward speed of the aircraft, reaching its maximum effect when the rotor blade is again perpendicular to the relative wind. Coaxial rotors avoid the effects of dissymmetry of lift through the use of two rotors turning in opposite directions, causing blades to advance on either side at the same time.
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For helicopters with two horizontally-mounted rotors, changes in attitude often require having each rotor behave inversely in response to the standard control inputs from the pilot. Those with coaxial rotors (like a Kamov Ka-50) have both rotors mounted on the same mast, one above the other on concentric drive shafts contra- rotating—spinning in opposite directions on a shared axis—and make yaw changes by increasing the collective pitch of the rotor spinning in the direction of the desired turn while simultaneously reducing the collective pitch of the other, creating dissymmetry of torque. Tandem-rotor craft (like a Boeing CH-47 Chinook) also employ two rotors spinning in opposite directions—termed counter-rotation when it occurs from two separate points on the same airframe—but have the rotors on separate drive shafts through masts at the nose and tail. This configuration uses differential collective pitch to change the overall pitch attitude of the aircraft.
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We take account of this dissymmetry in molecular sizes by assuming that individual polymer segments and individual solvent molecules occupy sites on a lattice. Each site is occupied by exactly one molecule of the solvent or by one monomer of the polymer chain, so the total number of sites is :N = N_1 + xN_2\, N_1 is the number of solvent molecules and N_2 is the number of polymer molecules, each of which has x segments. For a random walk on a lattice we can calculate the entropy change (the increase in spatial uncertainty) as a result of mixing solute and solvent. :\Delta S_m = -k[\,N_1\ln(N_1/N) + N_2\ln(xN_2/N)\,]\, where k is Boltzmann's constant. Define the lattice volume fractions \phi_1 and \phi_2 :\phi_1 = N_1/N\, :\phi_2 = xN_2/N\, These are also the probabilities that a given lattice site, chosen at random, is occupied by a solvent molecule or a polymer segment, respectively.
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