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Retardation
Retardation is the act or result of delaying; the extent to which anything is retarded or delayed; that which retards or delays. Retardation or retarded or similar may refer to: Medicine and biology * Mental retardation, also known as intellectual disability, a disorder characterized by significantly impaired cognitive functioning and deficits in adaptive behaviors * Psychomotor retardation, a slowing-down of thought and a reduction of physical movements in an individual * A form of heterochrony, able to cause effects such as neoteny, retention by adults of traits previously seen only in the young Physics and engineering * Retardation factor, in chromatography, the fraction of an analyte in the mobile phase of a chromatographic system * Retarded potential, in electrodynamics, electromagnetic potentials generated by time-varying electric current or charge distributions in the past * Retarded time, time when an electromagnetic field began to propagate from a point in a char ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intellectual Disability
Intellectual disability (ID), also known as general learning disability in the United Kingdom and formerly mental retardation, Rosa's Law, Pub. L. 111-256124 Stat. 2643(2010). is a generalized neurodevelopmental disorder characterized by significantly impaired intellectual and adaptive functioning. It is defined by an IQ under 70, in addition to deficits in two or more adaptive behaviors that affect everyday, general living. Intellectual functions are defined under DSM-V as reasoning, problem‑solving, planning, abstract thinking, judgment, academic learning, and learning from instruction and experience, and practical understanding confirmed by both clinical assessment and standardized tests. Adaptive behavior is defined in terms of conceptual, social, and practical skills involving tasks performed by people in their everyday lives. Intellectual disability is subdivided into syndromic intellectual disability, in which intellectual deficits associated with other medical and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retardation Factor
In chromatography, the retardation factor (''R'') is the fraction of an analyte in the mobile phase of a chromatographic system. In planar chromatography in particular, the retardation factor ''R''F is defined as the ratio of the distance traveled by the center of a spot to the distance traveled by the solvent front. Ideally, the values for ''RF'' are equivalent to the R values used in column chromatography. Although the term retention factor is sometimes used synonymously with retardation factor in regard to planar chromatography the term is not defined in this context. However, in column chromatography, the retention factor or capacity factor (''k'') is defined as the ratio of time an analyte is retained in the stationary phase to the time it is retained in the mobile phase, which is inversely proportional to the retardation factor. General definition In chromatography, the retardation factor, ''R'', is the fraction of the sample in the mobile phase at equilibrium, defined as: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Law Of Squares
The law of squares is a theorem concerning transmission lines. It states that the current injected into the line by a step in voltage reaches a maximum at a time proportional to the square of the distance down the line. The theorem is due to William Thomson, the future Lord Kelvin. The law had some importance in connection with submarine telegraph cables. The law For a step increase in the voltage applied to a transmission line, the law of squares can be stated as follows, :t_\text = RCx^2 where, :t_\text is the time at which the current on the line reaches a maximum :R is the resistance per metre of the line :C is the capacitance per metre of the line :x is the distance in metres from the input of the line. The law of squares is not just limited to step functions. It also applies to an impulse response or a rectangular function which are more relevant to telegraphy. However, the multiplicative factor is different in these cases. For an impulse it is 1/6 rather th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retarder (other)
Retarder may refer to: * ''Retarder'' (album), an album by The Unband * Retarder (chemistry), a chemical agent that slows down a chemical reaction * Retarder (mechanical engineering), a device for slowing down large trucks, lorries, buses, coaches and other vehicles * Retarder (railroad), a device to slow railroad freight cars as they are sorted into trains * Acrylic retarder, a chemical agent added to fine art acrylic paint to slow its short drying time * Dough retarder, a refrigerator used to slow down proofing of yeast when making dough * Retardation plate, an optical device that alters the polarization state of a light wave traveling through it * A component in weapons that slow down their rate of fire Rate of fire is the frequency at which a specific weapon can fire or launch its projectiles. This can be influenced by several factors, including operator training level, mechanical limitations, ammunition availability, and weapon condition. In m .... See also * Retardation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retardation Time
Retardation is the delayed response to an applied force or stress and can be described as "delay of the elasticity". Ideal elastic materials show an immediate deformation after applying a jump-like stress, and an immediate reformation after removing the stress afterwards in the jump-like form again. For viscoelastic samples, this elastic behaviour occurs with a certain time delay. The term "relaxation time" has been described. It is used in combination with tests presetting the strain ( deformation) or strain rate (shear rate), eg, when performing relaxation tests. On the other hand, the term "retardation time" is used for tests when presetting the stress, eg, when performing creep tests. See also * Creep-testing machine A creep-testing machine measures the alteration of a material after it has undergone stresses. Engineers use Creep machines to determine the stability and behaviour of a material when put through ordinary stresses. They determine how much stra ... Ref ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retard (pejorative) In modern use, retard is a pejorative term either for someone with a mental disability or for someone who is considered stupid, slow to understand, or ineffective in some way. The adjective retarded is in the same way used for something very foolish or stupid. Because it is now considered offensive, the word is commonly referred to by the euphemisms "r-word" and "r-slur". It was previously used as a medical term. The verb "to retard" means to delay or hold back, and so "retard" became known as a medical term in the late 19th and early 20th centuries to describe children with intellectual disabilities, or ''retarded mental development''. Until the 1960s, the terms '' moron'', ''idiot'', '' cretin'', and ''imbecile'' were all genuine, non-offensive terms to refer to people with mental intellectual disabilities and low intelligence. These words were discontinued in that form when concerns arose that they had developed negative meanings, with "retard" and "retarded" replacing them ... [...More Info...] [...Related Items...] |
