Top

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.

Characteristics

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.

Top (clothing)

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.

Design

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.

Types

Neck styles

See also

References

External links

Category of topological spaces

In mathematics, the category of topological spaces, often denoted Top, is the category whose objects are topological spaces and whose morphisms are continuous maps or some other variant; for example, objects are often assumed to be compactly generated. This is a category because the composition of two continuous maps is again continuous. The study of Top and of properties of topological spaces using the techniques of category theory is known as categorical topology.

N.B. Some authors use the name Top for the category with topological manifolds as objects and continuous maps as morphisms.

As a concrete category

Like many categories, the category Top is a concrete category (also known as a construct), meaning its objects are sets with additional structure (i.e. topologies) and its morphisms are functions preserving this structure. There is a natural forgetful functor

to the category of sets which assigns to each topological space the underlying set and to each continuous map the underlying function.

Frame (GUI)

A frame, or group box, is a type of box within which a collection of graphical control elements can be grouped as a way to show relationships visually, either because the items are functionally related (such as a radio button), or because they apply to related objects.

In HTML (where frame has another meaning, referring to an individually scrollable portion of a page), this kind of grouping box is called a fieldset after the HTML element of the same name.

In the image to the right, the top frame has no title. The two frames below have titles, and a radio button outside them, presumably to select one or the other. The lower of the two boxes is dimmed, or disabled, indicating its widgets cannot be selected. Note that each of the frames (as well as the area outside of the frames) has a checked radio button, while normally only one of the buttons can be selected.

Note that any widget, including nested frames, can be placed inside of a frame, not merely radio buttons.

References

Frame (nautical)

In ships, frames are ribs that are transverse bolted or welded to the keel. Frames support the hull and give the ship its shape and strength.

In wooden shipbuilding, each frame is composed of several sections, so that the grain of the wood can follow the curve of the frame. Starting from the keel, these are the floor (which crosses the keel and joins the frame to the keel), the first futtock, the second futtock, the top timber, and the rail stanchion. In steel shipbuilding, the entire frame can be formed in one piece by rivetting or welding sections; in this case the floor remains a separate piece, joining the frame on each side to the keel.

Frame numbers are the numerical values given to the frames; they begin at 1 with the first bow frame, and numbers increase sequentially to the last stern frame. The total number vary per the length of a ship.

The frames support lengthwise members which run parallel to the keel, from the bow to the stern; these may variously be called stringers, strakes, or clamps. The clamp supports the transverse deck beams, on which the deck is laid.

Frame (networking)

A frame is a digital data transmission unit in computer networking and telecommunication. A frame typically includes frame synchronization features consisting of a sequence of bits or symbols that indicate to the receiver the beginning and end of the payload data within the stream of symbols or bits it receives. If a receiver is connected to the system in the middle of a frame transmission, it ignores the data until it detects a new frame synchronization sequence.

In the OSI model of computer networking, a frame is the protocol data unit at the data link layer. Frames are the result of the final layer of encapsulation before the data is transmitted over the physical layer. A frame is "the unit of transmission in a link layer protocol, and consists of a link layer header followed by a packet." Each frame is separated from the next by an interframe gap. A frame is a series of bits generally composed of framing bits, the packet payload, and a frame check sequence. Examples are Ethernet frames, Point-to-Point Protocol (PPP) frames, Fibre Channel frames, and V.42 modem frames.