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Lightening Holes
Lightening holes are holes in structural components of machines and buildings used by a variety of engineering disciplines to make structures lighter. The edges of the hole may be flanged to increase the rigidity and strength of the component. The holes can be circular, triangular, elliptical, or rectangular and should have rounded edges, but they should never have sharp corners, to avoid the risk of stress risers, and they must not be too close to the edge of a structural component. Usage Aviation Lightening holes are often used in the aviation industry. This allows the aircraft to be lightweight as possible, retaining the durability and airworthiness of the aircraft structure. Maritime Lightening holes have also been used in marine engineering to increase seaworthiness of the vessel. Motorsports Lightening holes became a prominent feature of motor racing in the 1920s and 1930s. Chassis members, suspension components, engine housings and even connecting rods were drilled ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bullied Firth Brown Boxpok Wheel
Bullying is the use of force, coercion, hurtful teasing or threat, to abuse, aggressively dominate or intimidate. The behavior is often repeated and habitual. One essential prerequisite is the perception (by the bully or by others) of an imbalance of physical or social power. This imbalance distinguishes bullying from conflict. Bullying is a subcategory of aggressive behavior characterized by hostile intent, imbalance of power and repetition over a period of time. Bullying is the activity of repeated, aggressive behavior intended to hurt another individual, physically, mentally or emotionally. Bullying can be done individually or by a group, called mobbing, in which the bully may have one or more followers who are willing to assist the primary bully or who reinforce the bully by providing positive feedback such as laughing. Bullying in school and the workplace is also referred to as "peer abuse". Robert W. Fuller has analyzed bullying in the context of rankism. The Swedish-No ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parsons House - Geograph
Parsons may refer to: Places In the United States: * Parsons, Kansas, a city * Parsons, Missouri, an unincorporated community * Parsons, Tennessee, a city * Parsons, West Virginia, a town * Camp Parsons, a Boy Scout camp in the state of Washington * Lake Parsons, near Parsons, Kansas * Parsons Field, a multi-purpose stadium in Brookline, Massachusetts * Parsons Memorial Lodge, Yosemite National Park, California * Parsons Peak, a mountain in Yosemite National Park * Lucy Parsons Center, an all-volunteer, nonprofit collectively run radical, independent bookstore and community center, located in Jamaica Plain, Boston, Massachusetts On the Moon: * Parsons (crater) People * Parsons (surname) * Parsons Baronets, four baronetcies, two in Ireland, one in England, and one in the United Kingdom Companies * Parsons Brinckerhoff, engineering firm headquartered in New York City * Parsons Corporation, engineering firm headquartered in Centreville, Virginia * Parsons Marine Steam Turbine Co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aerospace Engineering
Aerospace engineering is the primary field of engineering concerned with the development of aircraft and spacecraft. It has two major and overlapping branches: aeronautical engineering and astronautical engineering. Avionics engineering is similar, but deals with the electronics side of aerospace engineering. "Aeronautical engineering" was the original term for the field. As flight technology advanced to include vehicles operating in outer space, the broader term "aerospace engineering" has come into use. Aerospace engineering, particularly the astronautics branch, is often colloquially referred to as "rocket science". Overview Flight vehicles are subjected to demanding conditions such as those caused by changes in atmospheric pressure and temperature, with structural loads applied upon vehicle components. Consequently, they are usually the products of various technological and engineering disciplines including aerodynamics, Air propulsion, avionics, materials science, stru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Structural Engineering
Structural engineering is a sub-discipline of civil engineering in which structural engineers are trained to design the 'bones and muscles' that create the form and shape of man-made structures. Structural engineers also must understand and calculate the stability, strength, rigidity and earthquake-susceptibility of built structures for buildings and nonbuilding structures. The structural designs are integrated with those of other designers such as architects and building services engineer and often supervise the construction of projects by contractors on site. They can also be involved in the design of machinery, medical equipment, and vehicles where structural integrity affects functioning and safety. See glossary of structural engineering. Structural engineering theory is based upon applied physical laws and empirical knowledge of the structural performance of different materials and geometries. Structural engineering design uses a number of relatively simple structural c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Civil Engineering
Civil engineering is a professional engineering discipline that deals with the design, construction, and maintenance of the physical and naturally built environment, including public works such as roads, bridges, canals, dams, airports, sewage systems, pipelines, structural components of buildings, and railways. Civil engineering is traditionally broken into a number of sub-disciplines. It is considered the second-oldest engineering discipline after military engineering, and it is defined to distinguish non-military engineering from military engineering. Civil engineering can take place in the public sector from municipal public works departments through to federal government agencies, and in the private sector from locally based firms to global Fortune 500 companies. History Civil engineering as a discipline Civil engineering is the application of physical and scientific principles for solving the problems of society, and its history is intricately linked to advances in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mechanical Engineering
Mechanical engineering is the study of physical machines that may involve force and movement. It is an engineering branch that combines engineering physics and mathematics principles with materials science, to design, analyze, manufacture, and maintain mechanical systems. It is one of the oldest and broadest of the engineering branches. Mechanical engineering requires an understanding of core areas including mechanics, dynamics, thermodynamics, materials science, structural analysis, and electricity. In addition to these core principles, mechanical engineers use tools such as computer-aided design (CAD), computer-aided manufacturing (CAM), and product lifecycle management to design and analyze manufacturing plants, industrial equipment and machinery, heating and cooling systems, transport systems, aircraft, watercraft, robotics, medical devices, weapons, and others. Mechanical engineering emerged as a field during the Industrial Revolution in Europe in the 18th century; ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Advisory Committee For Aeronautics
The National Advisory Committee for Aeronautics (NACA) was a United States federal agency founded on March 3, 1915, to undertake, promote, and institutionalize aeronautical research. On October 1, 1958, the agency was dissolved and its assets and personnel were transferred to the newly created National Aeronautics and Space Administration (NASA). NACA is an initialism, i.e., pronounced as individual letters, rather than as a whole word (as was NASA during the early years after being established). Among other advancements, NACA research and development produced the NACA duct, a type of air intake used in modern automotive applications, the NACA cowling, and several series of NACA airfoils, which are still used in aircraft manufacturing. During World War II, NACA was described as "The Force Behind Our Air Supremacy" due to its key role in producing working superchargers for high altitude bombers, and for producing the laminar wing profiles for the North American P-51 Mustang. NA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Truss
A truss is an assembly of ''members'' such as beams, connected by ''nodes'', that creates a rigid structure. In engineering, a truss is a structure that "consists of two-force members only, where the members are organized so that the assemblage as a whole behaves as a single object". A "two-force member" is a structural component where force is applied to only two points. Although this rigorous definition allows the members to have any shape connected in any stable configuration, trusses typically comprise five or more triangular units constructed with straight members whose ends are connected at joints referred to as ''nodes''. In this typical context, external forces and reactions to those forces are considered to act only at the nodes and result in forces in the members that are either tensile or compressive. For straight members, moments (torques) are explicitly excluded because, and only because, all the joints in a truss are treated as revolutes, as is necessary for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isogrid
Isogrid is a type of partially hollowed-out structure formed usually from a single metal plate (or face sheet) with triangular integral stiffening ribs (often called stringers). It was patented by McDonnell Douglas (now part of Boeing). It is extremely light and stiff. Compared to other materials, it is expensive to manufacture, and so it is restricted to spaceflight applications and some particularly critical parts of more general aerospace use. Theory and design Isogrid structures are related to sandwich-structured composite panels; both can be modeled using sandwich theory, which describes structures with separated, stiff face sheets and a lighter interconnecting layer. Isogrids are manufactured from single sheets of material and with large-scale triangular openings, and an open pattern to the flanges, compared to closed sheets and foam or honeycomb structures for the sandwich-composite structures. Isogrid structures are constituted by a thin skin reinforced with a lattice ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hollow Structural Section
A hollow structural section (HSS) is a type of metal profile with a hollow cross section. The term is used predominantly in the United States, or other countries which follow US construction or engineering terminology. HSS members can be circular, square, or rectangular sections, although other shapes such as elliptical are also available. HSS is only composed of structural steel per code. HSS is sometimes mistakenly referenced as ''hollow structural steel''. Rectangular and square HSS are also commonly called ''tube steel'' or ''box section''. Circular HSS are sometimes mistakenly called ''steel pipe'', although true steel pipe is actually dimensioned and classed differently from HSS. (HSS dimensions are based on exterior dimensions of the profile; pipes are also manufactured to an exterior tolerance, albeit to a different standard.) The corners of HSS are heavily rounded, having a radius which is approximately twice the wall thickness. The wall thickness is uniform around th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Honeycomb Structure
Honeycomb structures are natural or man-made Structure, structures that have the geometry of a honeycomb to allow the minimization of the amount of used material to reach minimal weight and minimal Material costs, material cost. The geometry of honeycomb structures can vary widely but the common feature of all such structures is an array of hollow cells formed between thin vertical walls. The cells are often columnar and hexagonal in shape. A honeycomb shaped structure provides a material with minimal density and relative high out-of-plane compression strength, compression properties and out-of-plane shear modulus, shear properties. Man-made honeycomb structural materials are commonly made by layering a honeycomb material between two thin layers that provide strength in Tension (physics), tension. This forms a plate-like assembly. Honeycomb materials are widely used where flat or slightly curved surfaces are needed and their high specific strength is valuable. They are widely us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strategic Materials
Strategic material is any sort of raw material that is important to an individual's or organization's strategic plan and supply chain management. Lack of supply of strategic materials may leave an organization or government vulnerable to disruption of the manufacturing of products which require those materials. It can also refer to a group or department that manages these materials. In government terms, they are materials, usually raw materials that have a particular strategic significance to a government or nation, often in time of war. Their strategic need is because of their crucial importance for either economic or military purposes. Some materials are relatively simple, but are required in great quantities during wartime. Others are obscure and technically complex. Although not required in large quantities, their irreplaceability and critical need makes them especially valuable. Foodstuffs are not generally classed as strategic materials: although vital, they are treated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
