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Self-propelled Particles
Self-propelled particles (SPP), also referred to as self-driven particles, are terms used by physicists to describe autonomous agents, which convert energy from the environment into directed or persistent motion. Natural systems which have inspired the study and design of these particles include walking, swimming or flying animals. Other biological systems include bacteria, cells, algae and other micro-organisms. Generally, self-propelled particles often refer to artificial systems such as robots or specifically designed particles such as swimming Janus colloids, bimetallic nanorods, nanomotors and walking grains. In the case of directed propulsion, which is driven by a chemical gradient, this is referred to as chemotaxis, observed in biological systems, e.g. bacteria quorum sensing and ant pheromone detection, and in synthetic systems, e.g. enzyme molecule chemotaxis and enzyme powered hard and soft particles. Overview Self-propelled particles interact with each other, which c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schwarm Wanderheuschrecke
A flight is a small military unit within the larger structure of an air force, naval air service, or army air corps; and is usually subservient of a larger squadron. A military aircraft flight is typically composed of four aircraft, though two to six aircraft may also form an aircraft flight; along with their aircrews and ground staff. In some very specific examples, typically involving historic aircraft, a flight may contain as many as twelve aircraft, as is the case with the Battle of Britain Memorial Flight (BBMF) of the British Royal Air Force (RAF). In most usages, two or more flights make up a squadron. Foreign languages equivalents include ''escadrille'' ( French), ''escuadrilla'' (Spanish), ''esquadrilha'' (Portuguese), ''zveno'' (Russian), and ''Schwarm'' (German). In the case of a non-flying, or 'ground flight', such as Mechanical Transport Flight (MTF), Supply Flight, Accounts Flight, etc; no aircraft, and a roughly equivalent number of support personnel may be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microswimmer
A microswimmer is a microscopic object with the ability to move in a fluid environment. Natural microswimmers are found everywhere in the natural world as biological microorganisms, such as bacteria, archaea, protists, sperm and microanimals. Since the turn of the millennium there has been increasing interest in manufacturing synthetic and biohybrid microswimmers. Although only two decades have passed since their emergence, they have already shown promise for various biomedical and environmental applications. Given the recent nature of the field, there is yet no consensus in the literature for the nomenclature of the microscopic objects this article refers to as "microswimmers". Among the many alternative names such objects are given in the literature, microswimmers, micro/nanorobots and micro/nanomotors are likely the most frequently encountered. Other common terms may be more descriptive, including information about the object shape, e.g., microtube or microhelix, its components, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desert Locust
The desert locust (''Schistocerca gregaria'') is a species of locust, a periodically swarming, short-horned grasshopper in the family Acrididae. They are found primarily in the deserts and dry areas of northern and eastern Africa, Arabia, and southwest Asia. During population surge years, they may extend north into parts of western Spain and southern Italy, south into Eastern Africa, and east in northern India. The desert locust shows periodic changes in its body form and can change in response to environmental conditions, over several generations, from a solitary, shorter-winged, highly fecund, non-migratory form to a gregarious, long-winged, and migratory phase in which they may travel long distances into new areas. In some years, they may thus form locust plagues, invading new areas, where they may consume all vegetation including crops, and at other times, they may live unnoticed in small numbers. During plague years, desert locusts can cause widespread damage to crops, as th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nymph Of Locust - Project Gutenberg EText 16410
A nymph ( grc, νύμφη, nýmphē, el, script=Latn, nímfi, label=Modern Greek; , ) in ancient Greek folklore is a minor female nature deity. Different from Greek goddesses, nymphs are generally regarded as personifications of nature, are typically tied to a specific place or landform, and are usually depicted as maidens. They were not necessarily immortal, but lived much longer than human beings. They are often divided into various broad subgroups, such as the Meliae (ash tree nymphs), the Dryads (oak tree nymphs), the Naiads (freshwater nymphs), the Nereids (sea nymphs), and the Oreads (mountain nymphs). Nymphs are often featured in classic works of art, literature, mythology, and fiction. Since the Middle Ages, nymphs have been sometimes popularly associated or even confused with fairies. Etymology The Greek word has the primary meaning of "young woman; bride, young wife" but is not usually associated with deities in particular. Yet the etymology of the noun remains ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Active Matter
Active matter is matter composed of large numbers of active "agents", each of which consumes energy in order to move or to exert mechanical forces. Such systems are intrinsically out of thermal equilibrium. Unlike thermal systems relaxing towards equilibrium and systems with boundary conditions imposing steady currents, active matter systems break time reversal symmetry because energy is being continually dissipated by the individual constituents. Most examples of active matter are biological in origin and span all the scales of the living, from bacteria and self-organising bio-polymers such as microtubules and actin (both of which are part of the cytoskeleton of living cells), to schools of fish and flocks of birds. However, a great deal of current experimental work is devoted to synthetic systems such as artificial self-propelled particles. Active matter is a relatively new material classification in soft matter: the most extensively studied model, the Vicsek model, dat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BIO-LGCA
In computational and mathematical biology, a biological lattice-gas cellular automaton (BIO-LGCA) is a discrete model for moving and interacting biological agents, a type of cellular automaton. The BIO-LGCA is based on the lattice-gas cellular automaton (LGCA) model used in fluid dynamics. A BIO-LGCA model describes cells and other motile biological agents as point particles moving on a discrete lattice, thereby interacting with nearby particles. Contrary to classic cellular automaton models, particles in BIO-LGCA are defined by their position and velocity. This allows to model and analyze active fluids and collective migration mediated primarily through changes in momentum, rather than density. BIO-LGCA applications include cancer invasion and cancer progression. Model definition As are all cellular automaton models, a BIO-LGCA model is defined by a lattice \mathcal, a state space \mathcal, a neighborhood \mathcal, and a rule \mathcal. * The lattice (\mathcal) defines the set ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Self-propulsion
Self-propulsion is the autonomous displacement of nano-, micro- and macroscopic natural and artificial objects, containing their own means of motion. Self-propulsion is driven mainly by interfacial phenomena. Various mechanisms of self-propelling have been introduced and investigated, which exploited phoretic effects, gradient surfaces, breaking the wetting symmetry of a droplet on a surface, the Leidenfrost effect The Leidenfrost effect is a physical phenomenon in which a liquid, close to a surface that is significantly hotter than the liquid's boiling point, produces an insulating vapor layer that keeps the liquid from boiling rapidly. Because of this re ..., the self-generated hydrodynamic and chemical fields originating from the geometrical confinements, and soluto- and thermo-capillary Marangoni flows. Self-propelled system demonstrate a potential as micro-fluidics devices and micro-mixers. Self-propelled liquid marbles have been demonstrated. See also * Self propelle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Active Brownian Particle
An active Brownian particle (ABP) is a model of self-propelled motion in a dissipative environment. It is a nonequilibrium generalization of a Brownian particle. The self-propulsion results from a force that acts on the particle's center of mass and points in the direction of an intrinsic body axis (the particle orientation). It is common to treat particles as spheres, though other shapes (such as rods) have also been studied. Both the center of mass and the direction of the propulsive force are subjected to white noise, which contributes a diffusive component to the overall dynamics. In its simplest version, the dynamics is overdamped and the propulsive force has constant magnitude, so that the magnitude of the velocity is likewise constant (speed-up to terminal velocity is instantaneous). The term ''active Brownian particle'' usually refers to this simple model and its straightforward extensions, though some authors have used it for more general self-propelled particle models ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physica A '', an international scientific journal for experimental and theoretical physics
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Physica may refer to: * Physics (Aristotle) * ''Physica'' (journal), a Dutch scientific journal :* ''Physica A'' :* ''Physica B'' ;* ''Physica C'' :* ''Physica D'' :* ''Physica E'' * ''Physica Scripta ''Physica Scripta'' is an international scientific journal for experimental and theoretical physics. It was established in 1970 as the successor of ''Arkiv för Fysik'' and published by the Royal Swedish Academy of Sciences (KVA). Since 2006, it h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Craig Reynolds (computer Graphics)
Craig W. Reynolds (born March 15, 1953), is an artificial life and computer graphics expert, who created the Boids artificial life simulation in 1986. Reynolds worked on the film ''Tron'' (1982) as a scene programmer, and on ''Batman Returns'' (1992) as part of the video image crew. Reynolds won the 1998 Academy Scientific and Technical Award The Scientific and Technical Awards are three different Honorary Awards that are given by the Academy of Motion Picture Arts and Sciences (AMPAS) during the annual Academy Awards season. The Awards have been presented since the 4th Academy Awards ... in recognition of "his pioneering contributions to the development of three-dimensional computer animation for motion picture production." He is the author of the '' OpenSteer'' library. References External linksCraig Reynolds' home page * [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boids
Boids is an artificial life program, developed by Craig Reynolds in 1986, which simulates the flocking behaviour of birds. His paper on this topic was published in 1987 in the proceedings of the ACM SIGGRAPH conference. The name "boid" corresponds to a shortened version of "bird-oid object", which refers to a bird-like object. "Boid" is also a New York Metropolitan dialect pronunciation for "bird." As with most artificial life simulations, Boids is an example of emergent behavior; that is, the complexity of Boids arises from the interaction of individual agents (the boids, in this case) adhering to a set of simple rules. The rules applied in the simplest Boids world are as follows: * separation: steer to avoid crowding local flockmates * alignment: steer towards the average heading of local flockmates * cohesion: steer to move towards the average position (center of mass) of local flockmates More complex rules can be added, such as obstacle avoidance and goal seeking. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tamás Vicsek
Tamás Vicsek (, born 10 May 1948, Budapest) is a Hungarian scientist with research interests in numerical studies of dense liquids, percolation theory, Monte Carlo simulation of cluster models, aggregation phenomena, fractal growth, pattern formation (computer and laboratory experiments), collective phenomena in biological systems ( flocking, oscillations, crowds), molecular motors, cell locomotion in vitro. He held the position of professor of physics at the Eötvös Loránd University, Budapest, Hungary, and was visiting scientists in various academia. at the website He is the namesake of the |
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