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Perimeter Fence
Demarcation of a perimeter, when the protection of assets, personnel or buildings is required, is normally affected by the building of a perimeter fence system. The level of protection offered varies according to the threat level to the perimeter. Different types of perimeter fencing include: * Timber fencing * Palisade fencing * Welded wire mesh fence fencing * Chain-link fencing * Rolled mesh fencing * Metal railings Vertical bar fencing has been the most popular form of perimeter security fence since the 1980s. Since the 2000s, welded wire mesh and acoustic barriers have also become popular types of perimeter fence around the world. Vertical bar, acoustic barriers and welded mesh are used in commercial projects and landmarks, in schools, and in airports and transport hubs. In high-security applications, sensors may be attached to the fence that generate alarms when they detect someone cutting, climbing, or lifting the fence fabric. Domestic and residential projects have si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perimeter
A perimeter is a closed path that encompasses, surrounds, or outlines either a two dimensional shape or a one-dimensional length. The perimeter of a circle or an ellipse is called its circumference. Calculating the perimeter has several practical applications. A calculated perimeter is the length of fence required to surround a yard or garden. The perimeter of a wheel/circle (its circumference) describes how far it will roll in one revolution. Similarly, the amount of string wound around a spool is related to the spool's perimeter; if the length of the string was exact, it would equal the perimeter. Formulas The perimeter is the distance around a shape. Perimeters for more general shapes can be calculated, as any path, with \int_0^L \mathrms, where L is the length of the path and ds is an infinitesimal line element. Both of these must be replaced by algebraic forms in order to be practically calculated. If the perimeter is given as a closed piecewise smooth plane curve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fencing
Fencing is a group of three related combat sports. The three disciplines in modern fencing are the foil, the épée, and the sabre (also ''saber''); winning points are made through the weapon's contact with an opponent. A fourth discipline, singlestick, appeared in the 1904 Olympics but was dropped after that and is not a part of modern fencing. Fencing was one of the first sports to be played in the Olympics. Based on the traditional skills of swordsmanship, the modern sport arose at the end of the 19th century, with the Italian school having modified the historical European martial art of classical fencing, and the French school later refining the Italian system. There are three forms of modern fencing, each of which uses a different kind of weapon and has different rules; thus the sport itself is divided into three competitive scenes: foil, épée, and sabre. Most competitive fencers choose to specialize in one weapon only. Competitive fencing is one of the five activitie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palisade
A palisade, sometimes called a stakewall or a paling, is typically a fence or defensive wall made from iron or wooden stakes, or tree trunks, and used as a defensive structure or enclosure. Palisades can form a stockade. Etymology ''Palisade'' derives from ''pale'', from the Latin word ', meaning stake, specifically when used side by side to create a wood defensive wall. Typical construction Typical construction consisted of small or mid-sized tree trunks aligned vertically, with as little free space in between as possible. The trunks were sharpened or pointed at the top, and were driven into the ground and sometimes reinforced with additional construction. The height of a palisade ranged from around a metre to as high as 3–4 m. As a defensive structure, palisades were often used in conjunction with earthworks. Palisades were an excellent option for small forts or other hastily constructed fortifications. Since they were made of wood, they could often be quickly and easil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Welded Wire Mesh Fence
Welded wire mesh fence is a steel fence consisting of wire strands electrically welded together to form a high strength mesh. The fencing is available in two formats: rolled mesh and rigid mesh. Over the last 30 years rigid mesh fencing has become the system of choice for demarcation across the UK, Europe and Australia. The rigid mesh system has proven popular, and is now a first choice on many types of projects including construction, civil, utilities and temporary works. Welded wire mesh fences are used predominantly as high security barriers where visibility through the fence is necessary or desirable. It is also used for animal enclosures in zoos. The longest stretch of rigid mesh fencing in the UK is on the Norton Bridge Flyover, with a continuous fence of 5.5 km. Types Styles * Profiled Rigid Mesh Panels * Double-Wire Rigid Mesh Panels (also known as Twin Wire) * 358 Prison Mesh Panels Finishes *Powder coating *Galvanization *Painted or sprayed *Stainless steel F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chain-link Fencing
A chain-link fence (also referred to as wire netting, wire-mesh fence, chain-wire fence, cyclone fence, hurricane fence, or diamond-mesh fence) is a type of woven fence usually made from galvanized or linear low-density polyethylene-coated steel wire. The wires run vertically and are bent into a zigzag pattern so that each "zig" hooks with the wire immediately on one side and each "zag" with the wire immediately on the other. This forms the characteristic diamond pattern seen in this type of fence. Development of chain-link fencing In the United Kingdom, the firm of Barnard, Bishop & Barnards was established in Norwich to produce chain-link fencing by machine. The process was developed by Charles Barnard in 1844 based on cloth weaving machines (up until that time, Norwich had a long history of cloth manufacture). The Anchor Post Fence Co. bought the rights to the wire-weaving machine and was the first company to manufacture chain-link fencing in the United States. Anchor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Airport
An airport is an aerodrome with extended facilities, mostly for commercial air transport. Airports usually consists of a landing area, which comprises an aerially accessible open space including at least one operationally active surface such as a runway for a plane to take off and to land or a helipad, and often includes adjacent utility buildings such as control towers, hangars and terminals, to maintain and monitor aircraft. Larger airports may have airport aprons, taxiway bridges, air traffic control centres, passenger facilities such as restaurants and lounges, and emergency services. In some countries, the US in particular, airports also typically have one or more fixed-base operators, serving general aviation. Operating airports is extremely complicated, with a complex system of aircraft support services, passenger services, and aircraft control services contained within the operation. Thus airports can be major employers, as well as important hubs for tourism ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perimeter Intrusion Detection Systems
A perimeter intrusion detection system (PIDS) is a device or sensor that detects the presence of an intruder attempting to breach the physical perimeter of a property, building, or other secured area. A PIDS is typically deployed as part of an overall security system and is often found in high-security environments such as correctional facilities, airports, military bases, and nuclear plants. Types of PIDS A wide range of intrusion detection technologies exist in the current marketplace. The U.S. Army, as part of their reference material for personnel responsible for planning and executing security programs, divides PIDS technologies into the following categories: * Active IR *Break wire *Electrostatic field *Fence detection (typically a microphonic cable or accelerometer mounted on the fence) * Ground motion *Magnetic * Microwave detectors * Near-IR beam break * Passive IR * Ported coaxial cable * Taut wire * Seismic Primary Application A PIDS typically acts as an ear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Garden
A garden is a planned space, usually outdoors, set aside for the cultivation, display, and enjoyment of plants and other forms of nature. The single feature identifying even the wildest wild garden is ''control''. The garden can incorporate both natural and artificial materials. Gardens often have design features including statuary, follies, pergolas, trellises, stumperies, dry creek beds, and water features such as fountains, ponds (with or without fish), waterfalls or creeks. Some gardens are for ornamental purposes only, while others also produce food crops, sometimes in separate areas, or sometimes intermixed with the ornamental plants. Food-producing gardens are distinguished from farms by their smaller scale, more labor-intensive methods, and their purpose (enjoyment of a hobby or self-sustenance rather than producing for sale, as in a market garden). Flower gardens combine plants of different heights, colors, textures, and fragrances to create interest and delight the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ornamental Metal
Ironwork is any weapon, Visual arts, artwork, utensil, or architectural feature made of iron, especially one used for decoration. There are two main types of ironwork: wrought iron and cast iron. While the use of iron dates as far back as 4000BC, it was the Hittites who first knew how to extract it (see iron ore) and develop weapons. Use of iron was mainly utilitarian until the Middle Ages; it became widely used for decoration in the period between the 16th and 19th century. Wrought iron Wrought ironwork is forged by a blacksmith using an anvil. The earliest known ironwork are beads from Jirzah in Egypt dating from 3500 BC and made from meteoric iron with the earliest use of smelted iron dates back to Mesopotamia. However, the first use of conventional smelting and purification techniques that modern society labels as true iron-working dates back to the Hittites in around 2000 BC. Knowledge about the use of iron spread from the Middle East to Greece and the Aegean region by 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hillsborough Disaster
The Hillsborough disaster was a fatal human crush during a football match at Hillsborough Stadium in Sheffield, South Yorkshire, England, on 15 April 1989. It occurred during an FA Cup semi-final between Liverpool and Nottingham Forest in the two standing-only central pens in the Leppings Lane stand allocated to Liverpool supporters. Shortly before kick-off, in an attempt to ease overcrowding outside the entrance turnstiles, the police match commander, David Duckenfield, ordered exit gate C to be opened, leading to an influx of supporters entering the pens. This resulted in overcrowding of those pens and the crush. With 97 deaths and 766 injuries, it has the highest death toll in British sporting history. Ninety-four people died on the day; another person died in hospital days later, and another victim died in 1993. In July 2021, a coroner ruled that Andrew Devine, who died 32 years after suffering severe and irreversible brain damage on the day, was the 97th victim. The match ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Privacy Fencing
A fence is a structure that encloses an area, typically outdoors, and is usually constructed from posts that are connected by boards, wire, rails or netting. A fence differs from a wall in not having a solid foundation along its whole length. Alternatives to fencing include a ditch (sometimes filled with water, forming a moat). Types By function * Agricultural fencing, to keep livestock in and/or predators out * Blast fence, a safety device that redirects the high energy exhaust from a jet engine * Sound barrier or acoustic fencing, to reduce noise pollution * Crowd control barrier * Privacy fencing, to provide privacy and security * Temporary fencing, to provide safety, security, and to direct movement; wherever temporary access control is required, especially on building and construction sites * Perimeter fencing, to prevent trespassing or theft and/or to keep children and pets from wandering away. * Decorative fencing, to enhance the appearance of a property, garden ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
