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Elliptical Umbilic Focal Surface
Elliptical may mean: * having the shape of an ellipse, or more broadly, any oval shape ** in botany, having an elliptic leaf shape ** of aircraft wings, having an elliptical planform * characterised by ellipsis (the omission of words), or by concision more broadly * an elliptical trainer, an exercise machine See also * Ellipse (other) In mathematics, an ellipse is a geometrical figure. Ellipse may also refer to: *MacAdam ellipse, an area in a chromaticity diagram * Elliptic leaf shape * Superellipse, a geometric figure As a name, it may also be: * The Ellipse, an area in Wa ... * Ellipsis (other) {{Disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ellipse
In mathematics, an ellipse is a plane curve surrounding two focus (geometry), focal points, such that for all points on the curve, the sum of the two distances to the focal points is a constant. It generalizes a circle, which is the special type of ellipse in which the two focal points are the same. The elongation of an ellipse is measured by its eccentricity (mathematics), eccentricity e, a number ranging from e = 0 (the Limiting case (mathematics), limiting case of a circle) to e = 1 (the limiting case of infinite elongation, no longer an ellipse but a parabola). An ellipse has a simple algebraic solution for its area, but only approximations for its perimeter (also known as circumference), for which integration is required to obtain an exact solution. Analytic geometry, Analytically, the equation of a standard ellipse centered at the origin with width 2a and height 2b is: : \frac+\frac = 1 . Assuming a \ge b, the foci are (\pm c, 0) for c = \sqrt. The standard parametric e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oval
An oval () is a closed curve in a plane which resembles the outline of an egg. The term is not very specific, but in some areas (projective geometry, technical drawing, etc.) it is given a more precise definition, which may include either one or two axes of symmetry of an ellipse. In common English, the term is used in a broader sense: any shape which reminds one of an egg. The three-dimensional version of an oval is called an ovoid. Oval in geometry The term oval when used to describe curves in geometry is not well-defined, except in the context of projective geometry. Many distinct curves are commonly called ovals or are said to have an "oval shape". Generally, to be called an oval, a plane curve should ''resemble'' the outline of an egg or an ellipse. In particular, these are common traits of ovals: * they are differentiable (smooth-looking), simple (not self-intersecting), convex, closed, plane curves; * their shape does not depart much from that of an ellipse, and * an o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elliptic (leaf Shape)
The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular or irregular, may be smooth or bearing hair, bristles or spines. For more terms describing other aspects of leaves besides their overall morphology see the leaf article. The terms listed here all are supported by technical and professional usage, but they cannot be represented as mandatory or undebatable; readers must use their judgement. Authors often use terms arbitrarily, or coin them to taste, possibly in ignorance of established terms, and it is not always clear whether because of ignorance, or personal preference, or because usages change with time or context, or because of variation between specimens, even specimens from the same plant. For example, whether to call leaves on the same tree "acuminate", "lanceolate", or "linear" could ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elliptical Wing
An elliptical wing is a wing planform whose leading and trailing edges each approximate two segments of an ellipse. It is not to be confused with annular wings, which may be elliptically shaped. Relatively few aircraft have adopted the elliptical wing, an even-smaller number of which attained mass production; the majority of aircraft that did use this feature were introduced during the 1930s and 1940s. Perhaps the most famous aircraft to feature an elliptical wing is the Supermarine Spitfire, a Second World War-era British fighter aircraft. Another major application was the Heinkel He 70 "Blitz", a German fast mail plane and reconnaissance bomber; early versions of the He 111 bomber also used such a wing configuration before a simpler design was adopted for economic reasons. Properties Theoretically, the most efficient way to create lift is to generate it in an elliptical spanwise distribution across the wing. There is no inherent superiority to pure elliptical shapes, and win ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ellipsis (linguistics)
In linguistics, ellipsis (from el, ἔλλειψις, ''élleipsis'' 'omission') or an elliptical construction is the omission from a clause of one or more words that are nevertheless understood in the context of the remaining elements. There are numerous distinct types of ellipsis acknowledged in theoretical syntax. Theoretical accounts of ellipsis seek to explain its syntactic and semantic factors, the means by which the elided elements are recovered, and the status of the elided elements. Theoretical accounts of ellipsis can vary greatly depending in part upon whether a constituency-based or a dependency-based theory of syntactic structure is pursued. Background Varieties of ellipsis have long formed a basis of linguistic theory that addresses basic questions of form–meaning correspondence: in particular, how the usual mechanisms of grasping a meaning from a form may be bypassed or supplanted via elliptical structures. In generative linguistics, the term ''ellipsis'' has ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Concision
Concision (also called brevity, laconicism, or conciseness) is a writing principle of eliminating redundancy.UNT Writing Lab. "Concision, Clarity, and Cohesion." Accessed June 19, 2012Link./ref> For example, this: * "It is a fact that most arguments must try to convince readers, that is the audience, that the arguments are true." expressed concisely, becomes * "Most arguments must demonstrate their truth."Program for Writing and Rhetoric, University of Colorado at Boulder. "Writing Tip #27: Revising for Concision and Clarity." Accessed June 19, 2012 ""It is a fact that most arguments must try to convince readers, that is the audience, that the arguments are true." Notice the beginning of the sentence: "it is a fact that" doesn't say much; if something is a fact, just present it. So begin the sentence with "most arguments..." and turn to the next bit of overlap. Look at "readers, that is the audience"; the redundancy can be reduced to "readers" or "audience." Now we have "Most argu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elliptical Trainer
An elliptical trainer or cross-trainer is a stationary exercise machine used to stair climb, walk, or run without causing excessive pressure to the joints, hence decreasing the risk of impact injuries. For this reason, people with some injuries can use an elliptical to stay fit, as the low impact affects them little. Elliptical trainers offer a non-impact cardiovascular workout that can vary from light to high intensity based on the speed of the exercise and the resistance preference set by the user. Elliptical trainers first entered the market in the 1990s, invented by Precor. Most elliptical trainers work the user's upper and lower body (although some models do not have moving upper body components). Though elliptical trainers are considered to be minimal-impact, they are an example of a weight-bearing form of exercise. They can be self-powered by user-generated motion or need to be plugged in for adjustment of motion and/or for supplying their electronic consoles and resis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ellipse (other)
In mathematics, an ellipse is a geometrical figure. Ellipse may also refer to: *MacAdam ellipse, an area in a chromaticity diagram * Elliptic leaf shape *Superellipse, a geometric figure As a name, it may also be: *The Ellipse, an area in Washington, D.C., United States *Ellipse Programmé, a French animation studio *Elipse, a Yugoslav rock band * ''Ellipse'', a 2009 album by Imogen Heap *"Ellipse", a song from the album ''In Silence We Yearn'' by Oh Hiroshima *Explorer Ellipse, an American homebuilt aircraft design *La société Ellipse, a French aircraft manufacturer Similar terms *Ellipsis, a punctuation mark *Ellipsis, a rhetorical suppression of words to give an expression more liveliness *Eclipse, an astronomical event *Elliptical Elliptical may mean: * having the shape of an ellipse, or more broadly, any oval shape ** in botany, having an elliptic leaf shape ** of aircraft wings, having an elliptical planform * characterised by ellipsis (the omission of words), or by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
