Efficient Energy Use, Efficiency
Efficiency is the extent to which time or effort is well used for the intended task or purpose. Efficiency may also refer to: * Efficiency (aerodynamics), the amount of lift divided by the aerodynamic drag * Efficiency (apartment), a one-room apartment * Efficiency (basketball), a statistical benchmark to compare the overall value of players * Efficiency (economics), a situation in which nothing can be improved without something else being hurt ** Efficiency (fair division), any changes made to assist one person would harm another * Efficiency (finance), non-mean-variance portfolio analysis, a way of showing that a portfolio is not efficient * Efficiency (mechanical) * Efficiency (network science), a measure of how efficiently a network exchanges information * Efficiency (statistics), a measure of quality of an estimator, experiment, or test * Energy efficiency (physics), the ratio of power consumed to useful power output See also * Efficient (horse) (foaled 2003), a New Z ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Efficiency
Efficiency is the often measurable ability to avoid wasting materials, energy, efforts, money, and time in doing something or in producing a desired result. In a more general sense, it is the ability to do things well, successfully, and without waste. In more mathematical or scientific terms, it signifies the level of performance that uses the least amount of inputs to achieve the highest amount of output. It often specifically comprises the capability of a specific application of effort to produce a specific outcome with a minimum amount or quantity of waste, expense, or unnecessary effort. Efficiency refers to very different inputs and outputs in different fields and industries. In 2019, the European Commission said: "Resource efficiency means using the Earth's limited resources in a sustainable manner while minimising impacts on the environment. It allows us to create more with less and to deliver greater value with less input." Writer Deborah Stone notes that efficiency is " ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Efficiency (aerodynamics)
In aerodynamics, the lift-to-drag ratio (or L/D ratio) is the lift generated by an aerodynamic body such as an aerofoil or aircraft, divided by the aerodynamic drag caused by moving through air. It describes the aerodynamic efficiency under given flight conditions. The L/D ratio for any given body will vary according to these flight conditions. For an aerofoil wing or powered aircraft, the L/D is specified when in straight and level flight. For a glider it determines the glide ratio, of distance travelled against loss of height. The term is calculated for any particular airspeed by measuring the lift generated, then dividing by the drag at that speed. These vary with speed, so the results are typically plotted on a 2-dimensional graph. In almost all cases the graph forms a U-shape, due to the two main components of drag. The L/D may be calculated using computational fluid dynamics or computer simulation. It is measured empirically by testing in a wind tunnel or in free flight te ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Efficiency (apartment)
A studio apartment, also known as a studio flat (United Kingdom, UK), a self-contained apartment (Nigeria), efficiency apartment, bed-sitter (Kenya) or bachelor apartment, is a small apartment (rarely a condo) in which the normal functions of a number of rooms – often the living room, bedroom, and kitchen – are combined into a single room. Design The studio apartment is an apartment with a single room. They are also known as single-room dwelling places or studio flats. A studio apartment typically consists of one large room that serves as the combined Living room, living, Dining room, dining, and bedroom. A variation, sometimes called an "alcove studio", may have a very small separate area; this wing or nook is off the main area, and can be used for dining or sleeping. The apartment's kitchen facilities may be located either in the central room or in a small separate area. The bathroom is usually in its own smaller room, while the toilet can be separated. Studio apartm ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Efficiency (basketball)
In professional basketball, the most commonly used statistical benchmark for comparing the overall value of players is called efficiency. It is a composite basketball statistic that is derived from basic individual statistics: points, rebounds, assists, steals, blocks, turnovers, and shot attempts. In theory, efficiency accounts for both a player's offensive contributions (points and assists) and their defensive contributions (steals and blocks), but it is generally thought that efficiency ratings favor offense-oriented players over those who specialize in defense, as defense is difficult to quantify with currently tabulated statistics. NBA EFF The NBA publishes online all of the basic basketball statistics recorded officially by the league. Individual player efficiency is expressed there by a stat referred to as 'efficiency' and abbreviated EFF. It is derived by a simple formula: : The formula was created by Kansas City sports reporter and statistician Martin Manley. DPR DPR ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Efficiency (economics)
In microeconomics, economic efficiency, depending on the context, is usually one of the following two related concepts: * Allocative or Pareto efficiency: any changes made to assist one person would harm another. * Productive efficiency: no additional output of one good can be obtained without decreasing the output of another good, and production proceeds at the lowest possible average total cost. These definitions are not equivalent: a market or other economic system may be allocatively but not productively efficient, or productively but not allocatively efficient. There are also other definitions and measures. All characterizations of economic efficiency are encompassed by the more general engineering concept that a system is efficient or optimal when it maximizes desired outputs (such as utility) given available inputs. Standards of thought There are two main standards of thought on economic efficiency, which respectively emphasize the distortions created by ''governments'' ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Efficiency (fair Division)
Pareto efficiency or Pareto optimality is a situation where no action or allocation is available that makes one individual better off without making another worse off. The concept is named after Vilfredo Pareto (1848–1923), Italian civil engineer and economist, who used the concept in his studies of economic efficiency and income distribution. The following three concepts are closely related: * Given an initial situation, a Pareto improvement is a new situation where some agents will gain, and no agents will lose. * A situation is called Pareto-dominated if there exists a possible Pareto improvement. * A situation is called Pareto-optimal or Pareto-efficient if no change could lead to improved satisfaction for some agent without some other agent losing or, equivalently, if there is no scope for further Pareto improvement. The Pareto front (also called Pareto frontier or Pareto set) is the set of all Pareto-efficient situations. Pareto originally used the word "optimal" for th ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Efficiency (finance)
In finance, marginal conditional stochastic dominance is a condition under which a portfolio can be improved in the eyes of all risk-averse investors by incrementally moving funds out of one asset (or one sub-group of the portfolio's assets) and into another. Each risk-averse investor is assumed to maximize the expected value of an increasing, concave von Neumann-Morgenstern utility function. All such investors prefer portfolio B over portfolio A if the portfolio return of B is second-order stochastically dominant over that of A; roughly speaking this means that the density function of A's return can be formed from that of B's return by pushing some of the probability mass of B's return to the left (which is disliked by all increasing utility functions) and then spreading out some of the density mass (which is disliked by all concave utility functions). If a portfolio A is marginally conditionally stochastically dominated by some incrementally different portfolio B, then it is said ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Mechanical Efficiency
In mechanical engineering, mechanical efficiency is a dimensionless number that measures the effectiveness of a mechanism or machine in transforming the power input to the device to power output. A machine is a mechanical linkage in which force is applied at one point, and the force does work moving a load at another point. At any instant the power input to a machine is equal to the input force multiplied by the velocity of the input point, similarly the power output is equal to the force exerted on the load multiplied by the velocity of the load. The mechanical efficiency of a machine (often represented by the Greek letter eta \eta) is a dimensionless number between 0 and 1 that is the ratio between the power output of the machine and the power input :\eta = \frac Since a machine does not contain a source of energy, nor can it store energy, from conservation of energy the power output of a machine can never be greater than its input, so the efficiency can never be greater than ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Efficiency (network Science)
In network science, the efficiency of a network is a measure of how efficiently it exchanges information and it is also called ''communication efficiency''. The underlying idea (and main assumption) is that the more distant two nodes are in the network, the less efficient their communication will be. The concept of efficiency can be applied to both local and global scales in a network. On a global scale, efficiency quantifies the exchange of information across the whole network where information is concurrently exchanged. The local efficiency quantifies a network's resistance to failure on a small scale. That is the local efficiency of a node i characterizes how well information is exchanged by its neighbors when it is removed. Definition The definition of communication efficiency assumes that the efficiency is inversely proportional to the distance, so in mathematical terms : \epsilon_ = \frac where \epsilon_ is the pairwise efficiency of nodes i, j \in V in network G = (V, ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Efficiency (statistics)
In statistics, efficiency is a measure of quality of an estimator, of an experimental design, or of a hypothesis testing procedure. Essentially, a more efficient estimator, needs fewer input data or observations than a less efficient one to achieve the Cramér–Rao bound. An ''efficient estimator'' is characterized by having the smallest possible variance, indicating that there is a small deviance between the estimated value and the "true" value in the L2 norm sense. The relative efficiency of two procedures is the ratio of their efficiencies, although often this concept is used where the comparison is made between a given procedure and a notional "best possible" procedure. The efficiencies and the relative efficiency of two procedures theoretically depend on the sample size available for the given procedure, but it is often possible to use the asymptotic relative efficiency (defined as the limit of the relative efficiencies as the sample size grows) as the principal compariso ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Energy Efficiency (physics)
Energy conversion efficiency (''η'') is the ratio between the useful output of an energy conversion machine and the input, in energy terms. The input, as well as the useful output may be chemical, electric power, mechanical work, light (radiation), or heat. The resulting value, ''η'' (eta), ranges between 0 and 1. Overview Energy conversion efficiency depends on the usefulness of the output. All or part of the heat produced from burning a fuel may become rejected waste heat if, for example, work is the desired output from a thermodynamic cycle. Energy converter is an example of an energy transformation. For example, a light bulb falls into the categories energy converter. \eta = \frac Even though the definition includes the notion of usefulness, efficiency is considered a technical or physical term. Goal or mission oriented terms include effectiveness and efficacy. Generally, energy conversion efficiency is a dimensionless number between 0 and 1.0, or 0% to 100%. ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Efficient (horse)
Efficient (foaled 23 August 2003) is a grey Thoroughbred racehorse gelding, bred in New Zealand, who won the 2007 Melbourne Cup and the 2006 Victoria Derby, both times ridden by Michael Rodd. Efficient was by the outstanding sire Zabeel from the mare Refused The Dance by Defensive Play (USA). He is a half brother to Guillotine, winner of the 2008 MVRC Dato Tan Chin Nam Stakes. In his first campaign in the spring of 2006 he put together five consecutive wins including the Group 2 Aami Vase at Moonee Valley and ending with a win in the VRC Derby by 2½ lengths. Following his Derby win Efficient was entered into the Melbourne Cup field, run three days later. However, he did not pull up well enough and so was scratched from the race and spelled instead. Returning in the autumn Efficient had a very light campaign of just two starts. In the 1,400-metre Group 3 Schweppervescence Cup he finished fourth behind Haradasun and fifth behind Miss Finland in the Group One Australian Guine ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |