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Coiling
A coiling or coil is a curve, helix, or spiral used for storing rope or cable in compact and reliable yet easily attainable form. They are often discussed with knots. Mountaineer's coil The mountaineer's coil (also alpine coil, climber's coil, lap coil, or standing coil) is a traditional method used by climbers to store and transport a climbing rope. This older style coil is noted as being more prone to twists and tangles than the butterfly coil, and care must be taken upon uncoiling to avoid these problems. Tying method Begin by taking hold of the rope in one hand with its end facing you. Coil the rope in arm's length sections with your free hand (extending it away from the other as far as it will reach to ensure each segment is of equal length as it is gathered). Alternate tucking the new gather in front and behind the previous coil to avoid putting a half-turn in the rope with each coil. When the last segment is reached form a short bight atop the gathered rope with i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Butterfly Coil
A coiling or coil is a curve, helix, or spiral used for storing rope or cable in compact and reliable yet easily attainable form. They are often discussed with knots. Mountaineer's coil The mountaineer's coil (also alpine coil, climber's coil, lap coil, or standing coil) is a traditional method used by climbers to store and transport a climbing rope. This older style coil is noted as being more prone to twists and tangles than the butterfly coil, and care must be taken upon uncoiling to avoid these problems. Tying method Begin by taking hold of the rope in one hand with its end facing you. Coil the rope in arm's length sections with your free hand (extending it away from the other as far as it will reach to ensure each segment is of equal length as it is gathered). Alternate tucking the new gather in front and behind the previous coil to avoid putting a half-turn in the rope with each coil. When the last segment is reached form a short bight atop the gathered rope with i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Standing End
This page explains commonly used terms related to knots. B Bend A bend is a knot used to join two lengths of rope. Bight A bight has two meanings in knotting. It can mean either any central part of a rope (between the standing end and the working end) or an arc in a rope that is at least as wide as a semicircle. "Any slack part of a rope between the two ends, particularly when curved or looped." In either case, a bight is a length of rope that does not cross itself. Knots that can be tied without use of the working end are called knots ''on the bight''. Binding knot Binding knots are knots that either constrict a single object or hold two objects snugly together. Whippings, seizings and lashings serve a similar purpose to binding knots, but contain too many wraps to be properly called a knot. In binding knots, the ends of rope are either joined together or tucked under the turns of the knot. Bitter end Another term for the working end. C Capsizing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rope
A rope is a group of yarns, plies, fibres, 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. Rope is thicker and stronger than similarly constructed cord, string, and twine. 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, they have a higher tensile strength, they are more resistant to rotting than ropes created from natural fibres, and they can be made to float on water. But synthetic ropes also possess certain disadvantages, including slipperiness, and some can be damaged more easily by UV light. 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. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Knot
A knot is an intentional complication in cordage which may be practical or decorative, or both. Practical knots are classified by function, including hitches, bends, loop knots, and splices: a ''hitch'' fastens a rope to another object; a ''bend'' fastens two ends of a rope to each another; a ''loop knot'' is any knot creating a loop; and ''splice'' denotes any multi-strand knot, including bends and loops. A knot may also refer, in the strictest sense, to a stopper or knob at the end of a rope to keep that end from slipping through a grommet or eye. Knots have excited interest since ancient times for their practical uses, as well as their topological intricacy, studied in the area of mathematics known as knot theory. History Knots and knotting have been used and studied throughout history. For example, Chinese knotting is a decorative handicraft art that began as a form of Chinese folk art in the Tang and Song Dynasty (960–1279 AD) in China, later popularized in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Working End
A knot is an intentional complication in cordage which may be practical or decorative, or both. Practical knots are classified by function, including hitches, bends, loop knots, and splices: a ''hitch'' fastens a rope to another object; a ''bend'' fastens two ends of a rope to each another; a ''loop knot'' is any knot creating a loop; and ''splice'' denotes any multi-strand knot, including bends and loops. A knot may also refer, in the strictest sense, to a stopper or knob at the end of a rope to keep that end from slipping through a grommet or eye. Knots have excited interest since ancient times for their practical uses, as well as their topological intricacy, studied in the area of mathematics known as knot theory. History Knots and knotting have been used and studied throughout history. For example, Chinese knotting is a decorative handicraft art that began as a form of Chinese folk art in the Tang and Song Dynasty (960–1279 AD) in China, later popularized in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reef Knot
The reef knot, or square knot, is an ancient and simple binding knot used to secure a rope or line around an object. It is sometimes also referred to as a Hercules knot. The knot is formed by tying a left-handed overhand knot between two ends, instead of around one end, and then a right-handed overhand knot via the same procedure, or vice versa. A common mnemonic for this procedure is "right over left; left over right", which is often appended with the rhyming suffix "... makes a knot both tidy and tight". Two consecutive overhands tied as described above of the same handedness will make a granny knot. The working ends of the reef knot must emerge both at the top or both at the bottom, otherwise a thief knot results. The reef knot is not recommended for tying two ropes together, because of the potential instability of the knot when not stabilized; something that has resulted in many deaths (see Misuse as a bend). Naming The reef knot is at least 4,000 years old. The n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Twisted Pair
Twisted pair cabling is a type of wiring used for communications in which two conductors of a single circuit are twisted together for the purposes of improving electromagnetic compatibility. Compared to a single conductor or an untwisted balanced pair, a twisted pair reduces electromagnetic radiation from the pair and crosstalk between neighboring pairs and improves rejection of external electromagnetic interference. It was invented by Alexander Graham Bell. For additional noise immunity, twisted-pair cabling may be shielded. Cable with shielding is known as shielded twisted pair (STP) and without as unshielded twisted pair (UTP). Explanation A twisted pair can be used as a balanced line, which as part of a balanced circuit can greatly reduce the effect of noise currents induced on the line by coupling of electric or magnetic fields. The idea is that the currents induced in each of the two wires are very nearly equal. The twisting ensures that the two wires are on ave ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Common-mode Rejection Ratio
In electronics, the common mode rejection ratio (CMRR) of a differential amplifier (or other device) is a metric used to quantify the ability of the device to reject common-mode signals, i.e. those that appear simultaneously and in-phase on both inputs. An ideal differential amplifier would have infinite CMRR, however this is not achievable in practice. A high CMRR is required when a differential signal must be amplified in the presence of a possibly large common-mode input, such as strong electromagnetic interference (EMI). An example is audio transmission over balanced line in sound reinforcement or recording. Theory Ideally, a differential amplifier takes the voltages, V_+ and V_- on its two inputs and produces an output voltage V_\mathrm=A_\mathrm(V_+ - V_-), where A_\mathrm is the differential gain. However, the output of a real differential amplifier is better described as : :V_ = A_\mathrm (V_+ - V_-) + \tfrac A_\mathrm (V_+ + V_-) where A_\mathrm is the "common-mode gai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Capacitance
Capacitance is the capability of a material object or device to store electric charge. It is measured by the change in charge in response to a difference in electric potential, expressed as the ratio of those quantities. Commonly recognized are two closely related notions of capacitance: ''self capacitance'' and ''mutual capacitance''. An object that can be electrically charged exhibits self capacitance, for which the electric potential is measured between the object and ground. Mutual capacitance is measured between two components, and is particularly important in the operations of the capacitor, a device designed for this purpose as an elementary Linear circuit, linear electronic component. Capacitance is a function only of the geometry of the design of the capacitor, e.g., the opposing surface area of the plates and the distance between them, and the permittivity of the dielectric material between the plates. For many dielectric materials, the permittivity and thus the capaci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Climbing Harness
A climbing harness is a device which allows a climber access to the safety of a rope. It is used in rock and ice climbing, abseiling, and lowering; this is in contrast to other activities requiring ropes for access or safety such as industrial rope work (such as window cleaning), construction, and rescue and recovery, which use safety harnesses instead. Overview While an improvised harness can be created out of length of rope or nylon webbing, commercially produced harnesses specific to climbing rock and ice are the norm. These characteristically include a dedicated tie-in loop, padding, and amenities such as gear loops. Most commercial climbing harnesses meet the guidelines and manufacturing standards of organizations such as the Union Internationale des Associations d'Alpinisme (UiAA) or European Committee for Standardization. Harnesses of users involved in climbing should be attached to dynamic (kernmantle) rope, which has natural shock-absorbing stretch. In via ferrata, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kernmantle Rope
Kernmantle rope () is rope constructed with its interior core protected by a woven exterior sheath designed to optimize strength, durability, and flexibility. The core fibers provide the tensile strength of the rope, while the sheath protects the core from abrasion during use. This is the only construction of rope that is considered to be life safety rope by most fire and rescue services. Parachute cord Parachute cord (also paracord or 550 cord when referring to type-III paracord) is a lightweight nylon kernmantle rope originally used in the suspension lines of parachutes. This cord is useful for many other tasks and is now used as a general purpose utility cord by both military personnel and civilians. Use as climbing rope One of the uses of kernmantle rope is as climbing rope. Nylon ropes that were used in yachts for hauling were tested and found useful in climbing and caving and are now the modern standard. The German company Edelrid introduced the first kernmantel rope ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
