- 行业: Printing & publishing
- Number of terms: 178089
- Number of blossaries: 0
- Company Profile:
McGraw Hill Financial, Inc. is an American publicly traded corporation headquartered in Rockefeller Center in New York City. Its primary areas of business are financial, publishing, and business services.
A friction type of energy-conversion mechanism used to retard, stop, or hold a vehicle or other moving element. The activating force is applied by a difference in air pressure. With an air brake, a slight effort by the operator can quickly apply full braking force.
Industry:Science
A fruit, represented commercially by such varieties as Martha, Hyslop, and Transcendent, comprising hybrids between <i>Malus baccata</i> (Siberian crabapple) and <i>M. domestica</i> (cultivated apple).
Industry:Science
A fuel containing a metal of high heat of combustion as a principal constituent. High propellant performance in either a rocket or an air-breathing engine is obtained when the heat of combusion of the fuel is high. Chemically, high heats of combustion are attained by the oxidation of the low-atomic-weight metals in the upper left-hand corner of the periodic table. The generally preferred candidates are lithium, beryllium, boron, carbon, magnesium, and aluminum.
Industry:Science
A fuel in the gaseous state whose potential heat energy can be readily transmitted and distributed through pipes from the point of origin directly to the place of consumption. The development and use of fuel gases is closely associated with the progress of civilization. Such gases have become prominent in the industrial development period since 1900.
Industry:Science
A fuel-burning internal combustion piston engine specially designed and built for minimum fuel consumption and light weight in proportion to developed shaft power. The rotating output shaft of the engine may be connected to a propeller, ducted fan, or helicopter rotor that, in turn, accelerates the surrounding air, imparting an equal and opposite thrust force for propulsion of the aircraft.
Industry:Science
A function first introduced in classical thermodynamics to provide a quantitative basis for the common observation that naturally occurring processes have a particular direction. Subsequently, in statistical thermodynamics, entropy was shown to be a measure of the number of microstates a system could assume. Finally, in communication theory, entropy is a measure of information. Each of these aspects will be considered in turn. Before the entropy function is introduced, it is necessary to discuss reversible processes.
Industry:Science
A function introduced by G. N. Lewis to facilitate the application of thermodynamics to real systems. Thus, when fugacities are substituted for partial pressures in the mass action equilibrium constant expression, which applies strictly only to the ideal case, a true equilibrium constant results for real systems as well.
Industry:Science
A function of the generalized coordinates and velocities of a dynamical system from which the equations of motion in Lagrange's form can be derived. The lagrangian function is denoted by <i>L</i>(<i>q</i><sub>1</sub>, …, <i>q</i><sub><i>f;˙</i></sub>, <i>q˙</i><sub>1</sub>, …, <i>q˙</i><sub><i>f;˙</i></sub>, <i>t</i>).
Industry:Science
A function that maps natural numbers to natural numbers and is special in that it must be calculable by using a precisely specified algorithm. The mathematical definitions of partial recursive functions and recursive functions were developed to give a precise mathematical characterization of those functions or operations on the natural numbers which are computable by using effective procedures.
Industry:Science
A functional system that includes an ecological community of organisms together with the physical environment, interacting as a unit. Ecosystems are characterized by flow of energy through food webs, production and degradation of organic matter, and transformation and cycling of nutrient elements. This production of organic molecules serves as the energy base for all biological activity within ecosystems. The consumption of plants by herbivores (organisms that consume living plants or algae) and detritivores (organisms that consume dead organic matter) serves to transfer energy stored in photosynthetically produced organic molecules to other organisms. Coupled to the production of organic matter and flow of energy is the cycling of elements.
Industry:Science
