Parabolically Shape: A parabolic antenna gen¬erally is composed of a parabolically shaped re¬flecting dish into which energy is radiated from a point source, such as a horn on the end of a wave guide. The dish may be cut away or its shape may be distorted to give the required shape to the beam of radiated energy.
The antenna usually is mechanically rotatable and is driven by a servo system, which is remotely controlled from the indicator location. The con¬trol may be a hand crank or a slewing selector.
THIS INFLUENCES design considerably. Few plots are symmetrical, but that really does not matter. An L-shape or a triangle can even offer more design potential than a rectangle. Perhaps the most difficult shape of all is a square, particularly when it is too small to subdivide as in many yards in front. A design for an awkward shape needs to be carefully thought out. A long thin area, for example, can be divided into contrasting sections with barriers across its width, but by leaving a narrow view running through from one end to the other you create an additional sight line. Furthermore, by placing an ornamental feature like a statue or seat at the far end, you gain the full benefit from the site's length while the screens minimize the disadvantages of its shape.See Also Spherical In Shape:Nearly all unlighted buoys are either a can buoy, which looks like a cylinder above water, or a nun buoy, which looks like a cone-topped cylinder above water. Some buoys are spherical in shape. In foreign waters, you may find a spar buoy, which looks a lot like a pile of wood floating upright. Lighted, sound, and combination (both light and sound) buoys exist in a variety of shapes; in such buoys, shape has no navigational significance.
Because the earth is essentially spherical, it is not possible to exact¬ly portray the size and relationship of its various features on a flat surface. To get as good a match as possible, chart makers use var¬ious projections—graphical and mathematical methods of repre¬senting a spherical surface on a flat one—each of which has advantages and disadvantages. Boaters on the high seas and coastal waters will use charts using the Mercator projection
On The Other Hand See Columnar Shape:Miniature and slow-growing conifers are particularly useful for providing winter interest. Chamaecyparis lawsoniana "Ellwoodii" Slow-growing and forms a dark-green columnar shape. For a golden color choose "Ellwood's Pillar."
Chamaecyparis pisifera "Boulevard" Slow-growing and forms a cone shape with intense silver-blue foliage.
Miniature and slow-growing conifers are particularly useful for providing winter interest. Chamaecyparis lawsoniana "Ellwoodii" Slow-growing and forms a dark-green columnar shape. For a golden color choose "Ellwood's Pillar."
Chamaecyparis pisifera "Boulevard" Slow-growing and forms a cone shape with intense silver-blue foliage.
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