Reentrant

	Reentrant Reentrant or re-entrant can refer to: Sciences Reentrancy (computing) in computer programming Reentrant mutex in computer science Reentry (neural circuitry) in neuroscience Concave polygon, AKA reentrant polygon Reentry into the atmosphere of an orbiting body Topography Re-entrant, a type of terrain feature commonly known as a draw. Salients, re-entrants and pockets in military tactics See also Reentrant dysrhythmia, a type of cardiac arrhythmia Reentrant tuning On a stringed instrument, a break in an otherwise ascending (or descending) order of string pitches is known as a re-entry. A re-entrant tuning, therefore, is a tuning which does not order all the strings (or more properly the courses) from the ... in music {{disambig ... [...More Info...] [...Related Items...] OR:* [Wikipedia] [Google] [Baidu] [Amazon]
	Reentrancy (computing) Reentrancy is a programming concept where a function or subroutine can be interrupted and then resumed before it finishes executing. This means that the function can be called again before it completes its previous execution. Reentrant code is designed to be safe and predictable when multiple instances of the same function are called simultaneously or in quick succession. A computer program or subroutine is called reentrant if multiple invocations can safely run concurrently on multiple processors, or if on a single-processor system its execution can be interrupted and a new execution of it can be safely started (it can be "re-entered"). The interruption could be caused by an internal action such as a jump or call (which might be a recursive call; reentering a function is a generalization of recursion), or by an external action such as an interrupt or signal. This definition originates from multiprogramming environments, where multiple processes may be active concurrently a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]
	Reentrant Mutex In computer science, the reentrant mutex (recursive mutex, recursive lock) is a particular type of mutual exclusion (mutex) device that may be locked multiple times by the same process/thread, without causing a deadlock. While any attempt to perform the "lock" operation on an ordinary mutex (lock) would either fail or block when the mutex is already locked, on a recursive mutex this operation will succeed if and only if the locking thread is the one that already holds the lock. Typically, a recursive mutex tracks the number of times it has been locked, and requires equally many unlock operations to be performed before other threads may lock it. Motivation Recursive mutexes solve the problem of non-reentrancy with regular mutexes: if a function that takes a lock and executes a callback is itself called by the callback, deadlock ensues. In pseudocode, that is the following situation: var m : Mutex // A non-recursive mutex, initially unlocked. function lock_and_call(i : Integ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]
picture info	Draw (terrain) A draw, sometimes known as a re-entrant in orienteering, is a terrain feature formed by two parallel ridges or Spur (mountain), spurs with low ground in between them. The long area of downward sloping low ground itself is the draw, and it is defined by the spurs surrounding it. Characteristics Draws are usually etched in a hill, hillside by water flow, are usually dry, but many contain an ephemeral stream or loose rocks from eroded rockfall. In a draw the ground always slopes downward in only one direction, and upward in the other three. The slope on a draw is generally quite sharp, with a clearly established Fall line (topography), fall line and characterized by a generally steep vertical drop over a short horizontal distance. There is essentially no level ground and little or no maneuver room within the draw. On a topographical map, the contour lines depicting a draw are U-shaped or V-shaped, pointing toward high ground. A draw can be conceptually thought of as the inverse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]
	Reentry (neural Circuitry) Reentry is a Biological neural network, neural structuring of the brain, which is characterized by the ongoing bidirectional exchange of signals along reciprocal axonal fibers linking two or more brain areas. It is hypothesized to allow for widely distributed groups of neurons to achieve Multisensory integration, integrated and synchronized Action potential, firing, which is proposed to be a requirement for consciousness, as outlined by Gerald Edelman and Giulio Tononi in their book ''A Universe of Consciousness''.. See also Embodied philosophy Neural Darwinism Primary consciousness Secondary consciousness References Neural circuitry Neurophysiology {{neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]
picture info	Concave Polygon A simple polygon that is not convex is called concave, non-convex or reentrant. A concave polygon will always have at least one reflex interior angle—that is, an angle with a measure that is between 180° degrees and 360° degrees exclusive. Polygon Some lines containing interior points of a concave polygon intersect its boundary at more than two points. Some diagonals of a concave polygon lie partly or wholly outside the polygon. Some sidelines of a concave polygon fail to divide the plane into two half-planes one of which entirely contains the polygon. None of these three statements holds for a convex polygon. As with any simple polygon, the sum of the internal angles of a concave polygon is (''n'' − 2) radians, equivalently 180°(''n'' − 2) degrees, where ''n'' is the number of sides. It is always possible to partition a concave polygon into a set of convex polygons. A polynomial-time algorithm for finding a decomposition into as few convex pol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]
picture info	Reentry Atmospheric entry (sometimes listed as Vimpact or Ventry) is the movement of an object from outer space into and through the gases of an atmosphere of a planet, dwarf planet, or natural satellite. Atmospheric entry may be ''uncontrolled entry,'' as in the entry of astronomical objects, space debris, or bolides. It may be ''controlled entry'' (or ''reentry'') of a spacecraft that can be navigated or follow a predetermined course. Methods for controlled atmospheric ''entry, descent, and landing'' of spacecraft are collectively termed as ''EDL''. Objects entering an atmosphere experience atmospheric drag, which puts mechanical stress on the object, and aerodynamic heating—caused mostly by compression of the air in front of the object, but also by drag. These forces can cause loss of mass (ablation) or even complete disintegration of smaller objects, and objects with lower compressive strength can explode. Objects have reentered with speeds ranging from 7.8 km/s for l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]
picture info	Salients, Re-entrants And Pockets A salient, also known as a bulge, is a battlefield feature that projects into enemy territory. The salient is surrounded by the enemy on multiple sides, making the troops occupying the salient vulnerable. The opponent's front line that borders a salient is referred to as a re-entrant – that is, an angle pointing inwards. A deep salient is vulnerable to being "pinched off" through the base, and this will result in a pocket in which the forces in the salient become isolated and without a supply line. On the other hand, a breakout of the forces within the salient through its tip can threaten the rear areas of the opposing forces outside it, leaving them open to an attack from behind. Implementation Salients can be formed in a number of ways. An attacker can produce a salient in the defender's line by either intentionally making a pincer movement around the military flanks of a strongpoint, which becomes the tip of the salient, or by making a broad, frontal attack which is held u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]
	Reentrant Dysrhythmia Arrhythmias, also known as cardiac arrhythmias, are irregularities in the heartbeat, including when it is too fast or too slow. Essentially, this is anything but normal sinus rhythm. A resting heart rate that is too fast – above 100 beats per minute in adults – is called tachycardia, and a resting heart rate that is too slow – below 60 beats per minute – is called bradycardia. Some types of arrhythmias have no symptoms. Symptoms, when present, may include palpitations or feeling a pause between heartbeats. In more serious cases, there may be lightheadedness, passing out, shortness of breath, chest pain, or decreased level of consciousness. While most cases of arrhythmia are not serious, some predispose a person to complications such as stroke or heart failure. Others may result in sudden death. Arrhythmias are often categorized into four groups: extra beats, supraventricular tachycardias, ventricular arrhythmias and bradyarrhythmias. Extra beats include premature a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]