windy-i-dzwigi: Crane (machine)

Evidence: 100 • authority: 72

A crane is a machine used to move materials both vertically and horizontally, utilizing a system of a boom, hoist, wire ropes or chains, and sheaves for lifting and relocating heavy objects within the swing of its boom. The device uses one or more simple machines, such as the lever and pulley, to create mechanical advantage to do its work. Cranes are commonly employed in transportation for the loading and unloading of freight, in construction for the movement of materials, and in manufacturing for the assembling of heavy equipment. The first known crane machine was the shaduf, a water-lifting device that was invented in ancient Mesopotamia (modern Iraq) and then appeared in ancient Egyptian…

Evidence: 55 • authority: 72

An elevator (North American English, Philippine English) or lift (Commonwealth English except Canada) is a machine that vertically transports people or freight between levels. They are typically powered by electric motors that drive traction cables and counterweight systems such as a hoist, although some pump hydraulic fluid to raise a cylindrical piston like a jack. Elevators are used in agriculture and manufacturing to lift materials. There are various types, like chain and bucket elevators, grain augers, and hay elevators. Modern buildings often have elevators to ensure accessibility, especially where ramps are not feasible. High-speed elevators are common in skyscrapers. Some elevators…

Evidence: 45 • authority: 72

A launching gantry (also called bridge building crane, and bridge-building machine) is a special-purpose mobile gantry crane used in bridge construction, specifically segmental bridges that use precast box girder bridge segments or precast girders in highway and high-speed rail bridge construction projects. The launching gantry is used to lift and support bridge segments or girders as they are placed while being supported by the bridge piers instead of the ground. While superficially similar, launching gantry machines should not be confused with movable scaffolding systems, which also are used in segmental bridge construction. Both feature long girders spanning multiple bridge spans which m…

Evidence: 39 • authority: 72

A crane vessel, crane ship, crane barge, or floating crane is a ship with a crane specialized in lifting heavy loads, typically exceeding 1,500 t (1,476 long tons; 1,653 short tons) for modern ships. The largest crane vessels are used for offshore construction. The cranes are fitted to conventional monohulls and barges, but the largest crane vessels are often catamaran or semi-submersible types which provide enhanced stability and reduced platform motion. Many crane vessels are fitted with one or more rotating cranes. Some of the largest crane vessels use fixed sheerlegs instead; in these designs, the crane cannot rotate relative to the ship, and the vessel must be manoeuvered to place load…

Evidence: 39 • authority: 92

Evidence: 34 • authority: 92

Logarithmic and Archimedean organic crystalline spirals.. Crystals can be found in many shapes but do not usually grow as spirals. Here we show that applying a non-uniform layer of a polymer blend onto slender centimeter-size organic crystals prestrains the crystals into hybrid dynamic elements with spiral shapes that respond reversibly to environmental variations in temperature or humidity by curling. Exposure to humidity results in partial uncurling within several seconds, whereby a logarithmic-type spiral crystal is transformed into an Archimedean one. Conical helices obtained by lateral pulling of the spirals can wind around solid objects similar to plant tendrils or lift suspended obje…

Evidence: 34 • authority: 92

Enabling continuous 24/7 vertical mobility in High-Rise buildings by integrating critical activity scheduling and night shift planning.. In high-rise construction projects, inefficient delivery of materials, equipment, and labor can impact the completion time of the project. So, improvement in vertical transportation could save time, facilitate the supply process and reduce costs. The methods introduced for efficiently planning lifts in the construction industry were focused on material transportation and the time of lift activity, which primarily used heuristics and simulations. One of the main challenges that has not been fully addressed in the literature is automatically prioritizing cri…

Evidence: 34 • authority: 72

Evidence: 34 • authority: 92

Evidence: 34 • authority: 72