A T-top (UK: T-bar) is an automobile roof with a removable panel on each side of a rigid bar running from the center of one structural bar between pillars to the center of the next structural bar. The panels of a traditional T-top are usually made of auto grade safety glass.
The T-top was patented by Gordon Buehrig on June 5, 1951. It was used in the design of the unsuccessful TASCO sports car.
The 1968 Chevrolet Corvette coupe was the first U.S.-built production automobile to feature a T-top roof. This increased the popularity of the coupe, such that it outsold the convertible and later led to the discontinuation of the Corvette convertible after 1975 until it was revived in 1986. Post-C3 models were built with a targa top instead of a T-top.
A T-top is a type of top for center console boats that is built with a "T" shaped structure when viewed from the side. The top is tall enough to stand under, and provides shade and rain protection for 2 or more passengers at the boat's helm. The T-Top is distinguished from other boat tops in that the entire structure is attached to the center console area, with no support brackets or straps connected to the outside of the boat, thereby providing 360-degree access around the boat for fishing and water activities.
Generally, t-tops are constructed from a high quality marine aluminum extrusion which is anodized for appearance longevity. The anodized aluminum extrusion requires a specific welding machine to assemble, usually a welding machine with pulse and square wave capacity. Marine extrusion is the lightest and most durable material for t-top construction.
Stainless steel is also an optional material for t-top construction. It is much heavier, more difficult, and costly to build, and may not have the structural durability or flexibility of its aluminum counterpart. However, it is often seen to be much more attractive.
A top is a toy designed to be spun rapidly on the ground, the motion of which causes it to remain precisely balanced on its tip because of inertia. Such toys have existed since antiquity. Traditionally tops were constructed of wood, sometimes with an iron tip, and would be set in motion by aid of a string or rope coiled around its axis which, when pulled quickly, caused a rapid unwinding that would set the top in motion. Today they are often built of plastic, and modern materials and manufacturing processes allow tops to be constructed with such precise balance that they can be set in motion by a simple twist of the fingers and twirl of the wrist without need for string or rope.
The motion of a top is produced in the most simple forms by twirling the stem using the fingers. More sophisticated tops are spun by holding the axis firmly while pulling a string or twisting a stick or pushing an auger. In the kinds with an auger, an internal weight rotates, producing an overall circular motion. Some tops can be thrown, while firmly grasping a string that had been tightly wound around the stem, and the centrifugal force generated by the unwinding motion of the string will set them spinning upon touching ground.
In the context of a module M over a ring R, the top of M is the largest semisimple quotient module of M if it exists.
For finite-dimensional k-algebras (k a field), if rad(M) denotes the intersection of all proper maximal submodules of M (the radical of the module), then the top of M is M/rad(M). In the case of local rings with maximal ideal P, the top of M is M/PM. In general if R is a semilocal ring (=semi-artinian ring), that is, if R/Rad(R) is an Artinian ring, where Rad(R) is the Jacobson radical of R, then M/rad(M) is a semisimple module and is the top of M. This includes the cases of local rings and finite dimensional algebras over fields.
A top is clothing that covers at least the chest, but which usually covers most of the upper human body between the neck and the waistline. The bottom of tops can be as short as mid-torso, or as long as mid-thigh. Men's tops are generally paired with pants, and women's with pants or skirts. Common types of tops are t-shirts, blouses and shirts.
The neckline is the highest line of the top, and may be as high as a head-covering hood, or as low as the waistline or bottom hem of the top. A top may be worn loose or tight around the bust or waist, and may have sleeves or shoulder straps, spaghetti straps (noodle straps), or may be strapless. The back may be covered or bare. Tops may have straps around the waist or neck, or over the shoulders.