Rope

A rope is a group of yarns, plies, or strands that are twisted or braided together into a larger and stronger form. Ropes have tensile strength and so can be used for dragging and lifting, but are too flexible to provide compressive strength. As a result, they cannot be used for pushing or similar compressive applications. Rope is thicker and stronger than similarly constructed cord, line, string, and twine. Ropes made from metal strands are called wire rope.

Construction

Rope may be constructed of any long, stringy, fibrous material, but generally is constructed of certain natural or synthetic fibres. Synthetic fibre ropes are significantly stronger than their natural fibre counterparts, but also possess certain disadvantages, including slipperiness.

Common natural fibres for rope are manila hemp, hemp, linen, cotton, coir, jute, straw, and sisal. Synthetic fibres in use for rope-making include polypropylene, nylon, polyesters (e.g. PET, LCP, HDPE, Vectran), polyethylene (e.g. Dyneema and Spectra), Aramids (e.g. Twaron, Technora and Kevlar) and acrylics (e.g. Dralon). Some ropes are constructed of mixtures of several fibres or use co-polymer fibres. Wire rope is made of steel or other metal alloys. Ropes have been constructed of other fibrous materials such as silk, wool, and hair, but such ropes are not generally available. Rayon is a regenerated fibre used to make decorative rope.

Rope (data structure)

In computer programming, a rope, or cord, is a data structure composed of smaller strings that is used for efficiently storing and manipulating a very long string. For example, a text editing program may use a rope to represent the text being edited, so that operations such as insertion, deletion, and random access can be done efficiently.

Description

A rope is a binary tree having leaf nodes that contain a short string. Each node has a weight value equal to the length of its string plus the sum of all leaf nodes' weight in its left subtree, namely the weight of a node is the total string length in its left subtree for a non-leaf node, or the string length of itself for a leaf node. Thus a node with two children divides the whole string into two parts: the left subtree stores the first part of the string. The right subtree stores the second part and its weight is the sum of the left child's weight and the length of its contained string.

The binary tree can be seen as several levels of nodes. The bottom level contains all the nodes that contain a string. Higher levels have fewer and fewer nodes. The top level consists of a single "root" node. The rope is built by putting the nodes with short strings in the bottom level, then attaching a random half of the nodes to parent nodes in the next level.

Rope (unit)

A rope may refer to any of several units of measurement initially determined or formed by ropes or knotted cords.

Length

The Greco-Roman schoenus, supposedly based on an Egyptian unit derived from a wound reed measuring rope, may also be given in translation as a "rope". According to Strabo, it varied in length between 30 to 120 stadia (roughly 5 to 20 km) depending on local custom.

The Byzantine equivalent, the schoinion or "little rope", varied between 60 to 72 Greek feet depending upon the location.

The Thai sen of 20 Thai fathoms or 40 m also means and is translated "rope".

The Somerset rope was a former English unit used in drainage and hedging. It was 20 feet (now precisely 6.096 m).

Area

The Romans used the schoenus as an alternate name for the half-jugerum formed by a square with sides of 120 Roman feet.

In Somerset, the rope could also double as a measure of area equivalent to 20 feet by 1 foot. Walls in Somerset were formerly sold "per rope" of 20 sq ft.

Garlic

In medieval English units, the rope of garlic was a set unit of 15 heads of garlic. 15 such ropes made up the "hundred" of garlic.

Ostia

Ostia may refer to:

Ostia (Rome)

Ostia (/ˈɒstɪə/) is a large neighbourhood in the X Municipio of the commune of Rome, Italy. Ostia (also called Ostia Lido or Lido di Roma or Lido di Ostia) is also the only municipio or district of Rome on the Tyrrhenian Sea and many Romans spend the summer holidays there. With about 85,000 inhabitants, Ostia is the first or second-most populated frazione of Italy, depending on whether Mestre is counted.

Geography

The town is located on the Tyrrhenian coast, close to Acilia and separated to Fiumicino by the mouth of the Tiber River (Tevere).

History

The neighbourhood was founded in 1884 near the remains of Ostia Antica, the port city of ancient Rome. This was possible after reclamation of the nearby marshland (the pond of Ostia), which was infested by malaria. The first inhabitants were peasants coming from Ravenna, in Romagna. Due to the opening of the urban Roma-Ostia railway in 1924, the new village soon became the favourite sea resort of the Romans, while many Art Nouveau houses were built on the waterfront.

Ostia (film)

Ostia is a 1970 Italian comedy film. It is the directorial debut of Sergio Citti.

Plot summary

In the poor and infamous suburb of Ostia two friends're living in a small apartment. One day a girl, ran away from home at the causes of harassment of her father, comes from the two, and so begins a friendship with them in solidarity. However, when the boys fall in love with her, all vying to be the enemies and reach of each other, until one day one of the two will die in a battle rival.

Cast

References

External links