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Von Kármán–Gabrielli Diagram
The von Kármán–Gabrielli diagram (also Gabrielli–von Kármán diagram, GvK diagram) is a diagram which compares the efficiency of transportation methods by plotting specific tractive force, or specific resistance against velocity (). It was first used by Theodore von Kármán Theodore von Kármán ( hu, ( szőllőskislaki) Kármán Tódor ; born Tivadar Mihály Kármán; 11 May 18816 May 1963) was a Hungarian-American mathematician, aerospace engineer, and physicist who was active primarily in the fields of aeronaut ... and Giuseppe Gabrielli in their 1950 paper on this subject. The basic idea is that formally, 1 kWh/100 km has the dimensional units of a force, a resistance force amounting to . website repository.cam.ac.uk; see page 328. ...
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Tractive Force
As used in mechanical engineering, the term tractive force can either refer to the total traction a vehicle exerts on a surface, or the amount of the total traction that is parallel to the direction of motion. In railway engineering, the term tractive effort is often used synonymously with tractive force to describe the pulling or pushing capability of a locomotive. In automotive engineering, the terms are distinctive: tractive effort is generally higher than tractive force by the amount of rolling resistance present, and both terms are higher than the amount of drawbar pull by the total resistance present (including air resistance and grade). The published tractive force value for any vehicle may be theoretical—that is, calculated from known or implied mechanical properties—or obtained via testing under controlled conditions. The discussion herein covers the term's usage in mechanical applications in which the final stage of the power transmission system is one ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theodore Von Kármán
Theodore von Kármán ( hu, ( szőllőskislaki) Kármán Tódor ; born Tivadar Mihály Kármán; 11 May 18816 May 1963) was a Hungarian-American mathematician, aerospace engineer, and physicist who was active primarily in the fields of aeronautics and astronautics. He was responsible for many key advances in aerodynamics, notably on supersonic and hypersonic airflow characterization. He is regarded as an outstanding aerodynamic theoretician of the 20th century. Early life Theodore von Kármán was born into a Jewish family in Budapest, Austria-Hungary, as Kármán Tódor, the son of Helen (Kohn, hu, Kohn Ilka) and Mór Kármán. One of his ancestors was Rabbi Judah Loew ben Bezalel. He studied engineering at the city's Royal Joseph Technical University, known today as Budapest University of Technology and Economics. After graduating in 1902 he moved to the German Empire and joined Ludwig Prandtl at the University of Göttingen, where he received his doctorate in 1908. He ta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giuseppe Gabrielli
Giuseppe Gabrielli (26 February 1903 – 29 November 1987) was an Italian aeronautics engineer. He is famous as the designer of numerous Italian military aircraft, including the Fiat G.50 Freccia and G.55 World War II fighters. He was born in Caltanissetta, Sicily, and studied at the Politecnico di Torino and in Aachen, Germany under Theodore von Karman. Gabrielli began his work as designer at Piaggio, but was soon called to FIAT by Giovanni Agnelli to lead his aeronautics section. Gabrielli designed 142 aircraft, all bearing his initial, including the G.50, the G.55, the G.80 (one of the first jets designed in Italy), the Aeritalia G.91, which won a contest for a NATO standard fighter in the 1950s, and the G.222, a military transport airplane, whose design was later evolved into the C-27J Spartan (with the addition of new engines and new avionics to the airframe). Gabrielli was awarded the Ludwig-Prandtl-Ring from the Deutsche Gesellschaft für Luft- und Raumfahrt (Ger ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oussama Khatib
Oussama Khatib ( ar, أسامة الخطيب) is a roboticist and a professor of computer science at Stanford University, and a Fellow of the IEEE. He is credited with seminal work in areas ranging from robot motion planning and control, human-friendly robot design, to haptic interaction and human motion synthesis. His work's emphasis has been to develop theories, algorithms, and technologies, that control robot systems by using models of their physical dynamics. These dynamic models are used to derive optimal controllers for complex robots that interact with the environment in real-time. Life Khatib received a Ph.D. in Electrical Engineering from Sup’Aero, Toulouse, France, in 1980. He then joined the Computer Science Department at Stanford University, and has been a member of the faculty there ever since. He is presently the director of the Stanford Robotics Laboratory, and a member of the Stanford University Bio-X Initiative. Work Academic work Khatib's first seminal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Force
In physics, a force is an influence that can change the motion of an object. A force can cause an object with mass to change its velocity (e.g. moving from a state of rest), i.e., to accelerate. Force can also be described intuitively as a push or a pull. A force has both magnitude and direction, making it a vector quantity. It is measured in the SI unit of newton (N). Force is represented by the symbol (formerly ). The original form of Newton's second law states that the net force acting upon an object is equal to the rate at which its momentum changes with time. If the mass of the object is constant, this law implies that the acceleration of an object is directly proportional to the net force acting on the object, is in the direction of the net force, and is inversely proportional to the mass of the object. Concepts related to force include: thrust, which increases the velocity of an object; drag, which decreases the velocity of an object; and torque, which pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ragone Plot
A Ragone plot ( ) is a plot used for comparing the energy density of various energy-storing devices. On such a chart the values of specific energy (in W·h/ kg) are plotted versus specific power (in W/kg). Both axes are logarithmic, which allows comparing performance of very different devices. Ragone plots can reveal information about gravimetric energy density, but do not convey details about volumetric energy density. The Ragone plot was first used to compare performance of batteries. However, it is suitable for comparing any energy-storage devices, as well as energy devices such as engines, gas turbines, and fuel cells. The plot is named after David V. Ragone. Conceptually, the vertical axis describes how much energy is available per unit mass, while the horizontal axis shows how quickly that energy can be delivered, otherwise known as power per unit mass. A point in a Ragone plot represents a particular energy device or technology. The amount of time (in hours) during ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diagrams
A diagram is a symbolic representation of information using visualization techniques. Diagrams have been used since prehistoric times on walls of caves, but became more prevalent during the Enlightenment. Sometimes, the technique uses a three-dimensional visualization which is then projected onto a two-dimensional surface. The word '' graph'' is sometimes used as a synonym for diagram. Overview The term "diagram" in its commonly used sense can have a general or specific meaning: * ''visual information device'' : Like the term "illustration", "diagram" is used as a collective term standing for the whole class of technical genres, including graphs, technical drawings and tables. * ''specific kind of visual display'' : This is the genre that shows qualitative data with shapes that are connected by lines, arrows, or other visual links. In science the term is used in both ways. For example, Anderson (1997) stated more generally: "diagrams are pictorial, yet abstract, represent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
