|
Shell Technology Centre Amsterdam
Shell may refer to: Architecture and design * Shell (structure), a thin structure ** Concrete shell, a thin shell of concrete, usually with no interior columns or exterior buttresses Science Biology * Seashell, a hard outer layer of a marine animal, found on beaches * Eggshell * Nutshell * Exoskeleton, an external covering of some animals ** Mollusc shell *** Bivalve shell *** Gastropod shell ** Shell, of a brachiopod * Turtle shell * Armadillo shell Physics and chemistry * Electron shell or a principal energy level of electrons outside an atom's nucleus * Nuclear shell model, a principal energy level of nucleons within an atom's nucleus * On shell and off shell, quantum field theory concepts depending on whether classical equations of motion are obeyed Mathematics * Spherical shell Organisations * Shell plc formerly Royal Dutch Shell plc, a British multinational oil and gas company ** Shell Oil Company or Shell USA ** Shell Australia ** Shell Canada ** Shell Nigeria * Shell co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shell (structure)
A shell is a three-dimensional solid structural element whose thickness is very small compared to its other dimensions. It is characterized in structural terms by mid-plane stress which is both coplanar and normal to the surface. A shell can be derived from a plate (structure), plate in two steps: by initially forming the middle surface as a singly or doubly curved surface, then by applying loads which are coplanar to the plate's plane (geometry), plane thus generating significant stresses. Materials range from concrete (a ''concrete shell'') to fabric (as in ''fabric structures''). Thin-shell structures (also called plate and shell structures) are lightweight constructions using List of structural elements, shell elements. These elements, typically curved, are assembled to make large structures. Typical applications include aircraft fuselages, boat hulls, and the roofs of large buildings. Definition A thin shell is defined as a shell with a thickness which is small compared to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shell USA
Shell USA, Inc. (formerly Shell Oil Company, Inc.) is the United States–based wholly owned subsidiary of Shell plc, a UK-based transnational corporation " oil major" which is among the largest oil companies in the world. Approximately 18,000 Shell employees are based in the U.S. Its U.S. headquarters are in Houston, Texas. Shell USA, including its consolidated companies and its share in equity companies, is one of America's largest oil and natural gas producers, natural gas marketers, fuel marketers and petrochemical manufacturers. History In 1979, Shell purchased Belridge Oil Company for $3.65 billion, which at the time was called the "biggest cash takeover in American history" by US government sources. In 1997, Shell and Texaco entered into two refining/marketing joint ventures. One combined their Midwestern and Western operations and was known as Equilon. The other, known as Motiva Enterprises, combined the Eastern and Gulf Coast operations of Shell Oil and Star Enter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Expert System
In artificial intelligence (AI), an expert system is a computer system emulating the decision-making ability of a human expert. Expert systems are designed to solve complex problems by reasoning through bodies of knowledge, represented mainly as if–then rules rather than through conventional procedural programming code. Expert systems were among the first truly successful forms of AI software. They were created in the 1970s and then proliferated in the 1980s, being then widely regarded as the future of AI — before the advent of successful artificial neural networks. An expert system is divided into two subsystems: 1) a ''knowledge base'', which represents facts and rules; and 2) an '' inference engine'', which applies the rules to the known facts to deduce new facts, and can include explaining and debugging abilities. History Early development Soon after the dawn of modern computers in the late 1940s and early 1950s, researchers started realizing the immense potential th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
