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Frame Loss Ratio
A frame is often a structural system that supports other components of a physical construction and/or steel frame that limits the construction's extent. Frame and FRAME may also refer to: Physical objects In building construction *Framing (construction), a building term known as light frame construction * Framer, a carpenter who assembles major structural elements in constructing a building * A-frame, a basic structure designed to bear a load in a lightweight economical manner ** A-frame house, a house following the same principle *Door frame or window frame, fixed structures to which the hinges of doors or windows are attached *Frame and panel, a method of woodworking *Space frame, a method of construction using lightweight or light materials *Timber framing, a method of building for creating framed structures of heavy timber or willow wood In vehicles *Frame (aircraft), structural rings in an aircraft fuselage *Frame (nautical), the skeleton of a boat * Bicycle frame, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Structural System
A structure is an arrangement and organization of interrelated elements in a material object or system, or the object or system so organized. Material structures include man-made objects such as buildings and machines and natural objects such as biological organisms, minerals and chemicals. Abstract structures include data structures in computer science and musical form. Types of structure include a hierarchy (a cascade of one-to-many relationships), a network featuring many-to-many links, or a lattice featuring connections between components that are neighbors in space. Load-bearing Buildings, aircraft, skeletons, anthills, beaver dams, bridges and salt domes are all examples of load-bearing structures. The results of construction are divided into buildings and non-building structures, and make up the infrastructure of a human society. Built structures are broadly divided by their varying design approaches and standards, into categories including building structures, ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frame (loudspeaker)
A loudspeaker (commonly referred to as a speaker or speaker driver) is an electroacoustic transducer that converts an electrical audio signal into a corresponding sound. A ''speaker system'', also often simply referred to as a "speaker" or "loudspeaker", comprises one or more such speaker ''drivers'', an enclosure, and electrical connections possibly including a crossover network. The speaker driver can be viewed as a linear motor attached to a diaphragm which couples that motor's movement to motion of air, that is, sound. An audio signal, typically from a microphone, recording, or radio broadcast, is amplified electronically to a power level capable of driving that motor in order to reproduce the sound corresponding to the original unamplified electronic signal. This is thus the opposite function to the microphone; indeed the ''dynamic speaker'' driver, by far the most common type, is a linear motor in the same basic configuration as the dynamic microphone which uses such a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frames And Locales
In mathematics, especially in order theory, a complete Heyting algebra is a Heyting algebra that is complete as a lattice. Complete Heyting algebras are the objects of three different categories; the category CHey, the category Loc of locales, and its opposite, the category Frm of frames. Although these three categories contain the same objects, they differ in their morphisms, and thus get distinct names. Only the morphisms of CHey are homomorphisms of complete Heyting algebras. Locales and frames form the foundation of pointless topology, which, instead of building on point-set topology, recasts the ideas of general topology in categorical terms, as statements on frames and locales. Definition Consider a partially ordered set (''P'', ≤) that is a complete lattice. Then ''P'' is a complete Heyting algebra or frame if any of the following equivalent conditions hold: * ''P'' is a Heyting algebra, i.e. the operation (x\land\cdot) has a right adjoint (also called the lower adjo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frame (linear Algebra)
In linear algebra, a frame of an inner product space is a generalization of a basis of a vector space to sets that may be linearly dependent. In the terminology of signal processing, a frame provides a redundant, stable way of representing a signal. Frames are used in error detection and correction and the design and analysis of filter banks and more generally in applied mathematics, computer science, and engineering. Definition and motivation Motivating example: computing a basis from a linearly dependent set Suppose we have a set of vectors \ in the vector space ''V'' and we want to express an arbitrary element \mathbf \in V as a linear combination of the vectors \, that is, we want to find coefficients c_k such that : \mathbf = \sum_k c_k \mathbf_k If the set \ does not span V, then such coefficients do not exist for every such \mathbf. If \ spans V and also is linearly independent, this set forms a basis of V, and the coefficients c_ are uniquely determined by \mathbf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frame Bundle
In mathematics, a frame bundle is a principal fiber bundle F(''E'') associated to any vector bundle ''E''. The fiber of F(''E'') over a point ''x'' is the set of all ordered bases, or ''frames'', for ''E''''x''. The general linear group acts naturally on F(''E'') via a change of basis, giving the frame bundle the structure of a principal GL(''k'', R)-bundle (where ''k'' is the rank of ''E''). The frame bundle of a smooth manifold is the one associated to its tangent bundle. For this reason it is sometimes called the tangent frame bundle. Definition and construction Let ''E'' → ''X'' be a real vector bundle of rank ''k'' over a topological space ''X''. A frame at a point ''x'' ∈ ''X'' is an ordered basis for the vector space ''E''''x''. Equivalently, a frame can be viewed as a linear isomorphism :p : \mathbf^k \to E_x. The set of all frames at ''x'', denoted ''F''''x'', has a natural right action by the general linear group GL(''k'', R) of invertible ''k'' × ''k'' matrices: a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ordered Basis
In mathematics, a set of vectors in a vector space is called a basis if every element of may be written in a unique way as a finite linear combination of elements of . The coefficients of this linear combination are referred to as components or coordinates of the vector with respect to . The elements of a basis are called . Equivalently, a set is a basis if its elements are linearly independent and every element of is a linear combination of elements of . In other words, a basis is a linearly independent spanning set. A vector space can have several bases; however all the bases have the same number of elements, called the ''dimension'' of the vector space. This article deals mainly with finite-dimensional vector spaces. However, many of the principles are also valid for infinite-dimensional vector spaces. Definition A basis of a vector space over a field (such as the real numbers or the complex numbers ) is a linearly independent subset of that spans . This mean ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frame (beekeeping)
A beehive is an enclosed structure in which some honey bee species of the subgenus '' Apis'' live and raise their young. Though the word ''beehive'' is commonly used to describe the nest of any bee colony, scientific and professional literature distinguishes ''nest'' from ''hive''. ''Nest'' is used to discuss colonies that house themselves in natural or artificial cavities or are hanging and exposed. ''Hive'' is used to describe an artificial/man-made structure to house a honey bee nest. Several species of ''Apis'' live in colonies, but for honey production the western honey bee (''Apis mellifera'') and the eastern honey bee (''Apis cerana'') are the main species kept in hives. The nest's internal structure is a densely packed group of hexagonal prismatic cells made of beeswax, called a honeycomb. The bees use the cells to store food (honey and pollen) and to house the brood (eggs, larvae, and pupae). Beehives serve several purposes: production of honey, pollination of near ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Frame
The water frame is a spinning frame that is powered by a water-wheel. Water frames in general have existed since Ancient Egypt times. Richard Arkwright, who patented the technology in 1769, designed a model for the production of cotton thread; this was first used in 1765. The Arkwright water frame was able to spin 96 threads at a time, which was an easier and faster method than ever before. The design was partly based on a spinning machine built for Thomas Highs by clockmaker John Kay, who was hired by Arkwright. Being run on water power, it produced stronger and harder yarn than the then-famous "spinning jenny", and propelled the adoption of the modern factory system. Another water-powered frame for the production of textiles was developed in 1760, in the early industrialized town of Elberfeld, Prussia (now in Wuppertal, Germany), by German bleach plant owner Johann Heinrich Bockmühl. The name ''water frame'' is derived from the use of a water wheel to drive a number of spi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinning Frame
The spinning frame is an Industrial Revolution invention for spinning thread or yarn from fibres such as wool or cotton in a mechanized way. It was developed in 18th-century Britain by Richard Arkwright and John Kay. Historical context In 1760 England, yarn production from wool, flax and cotton was still a cottage industry in which fibres were carded and spun by hand using a spinning wheel. As the textile industry expanded its markets and adopted faster machines, yarn supplies became scarce especially due to innovations such as the doubling of the loom speed after the invention of the flying shuttle. High demand for yarn spurred invention of the spinning jenny in 1764, followed closely by the invention of the spinning frame, later developed into the water frame (patented in 1769). Mechanisms had increased production of yarn so dramatically that by 1830 the yarn cottage industry in England could no longer compete and all spinning was carried out in factories. Development R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Receiver (firearms)
In firearms terminology, the firearm frame or receiver is the part of a firearm which integrates other components by providing housing for internal action components such as the hammer, bolt or breechblock, firing pin and extractor, and has threaded interfaces for externally attaching ("receiving") components such as the barrel, stock, trigger mechanism and iron/optical sights. The receiver is often made of forged, machined, or stamped steel or aluminium; in addition to these traditional materials, modern science and engineering have introduced polymers and sintered metal powders to receiver construction. Mounting A barrel can be fixed to the receiver using barrel and receiver action threads or similar methods. In US law For the purposes of United States law, the receiver or frame is legally the firearm, and as such it is the controlled part. The definition of which assembly is the legal receiver varies from firearm to firearm, under US law. Generally, the law requ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Picture Frame
A picture frame is a protective and decorative edging for a picture, such as a painting or photograph. It makes displaying the work safer and easier and both sets the picture apart from its surroundings and aesthetically integrates it with them. Construction A picture frame is a container that borders the perimeter of a picture, and is used for the protection, display, and visual appreciation of objects and imagery such as photographs, canvas paintings, drawings and prints, posters, mirrors, shadow box memorabilia, and textiles. Traditionally picture frames have been made of wood, and it remains very popular because wood frames can provide strength, be shaped in a broad range of profiles, and allow a variety of surface treatments. Other materials include metals, e.g. silver, bronze, aluminum, and stiff plastics such as polystyrene. A frame surface may be of any color or texture. Both genuine gilding and imitation gold remain popular, although many other surfaces are to be found ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lever Frame
Mechanical railway signalling installations rely on lever frames for their operation to interlock the signals, track locks and points to allow the safe operation of trains in the area the signals control. Usually located in the signal box, the levers are operated either by the signalman or the pointsman. The world's largest lever frame is believed to have been in the Spencer Street No.1 signal box in Melbourne, Australia, which had 191 levers, but was decommissioned in 2008. The largest, currently operational, lever frame is located at Severn Bridge Junction in Shrewsbury, England, and has 180 levers; although most of them have now been taken out of use. Overview The lever frame is located in the signal box, which can be a building at ground level or a tower, separated from or connected to an existing station building. Early lever frames were also built as ''ground frames'' next to the track, without any form of shelter and were usually operated by traincrew and not per ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
