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Driving Factors
In energy monitoring and targeting, a driving factor is something recurrent and measurable whose variation explains variation in energy consumption. The term ''independent variable'' is sometimes used as a synonym. One of the most common driving factors is the weather, expressed usually as heating or cooling degree days. In energy-intensive processes, production throughputs would usually be used. For electrical circuits feeding outdoor lighting, the number of hours of darkness can be employed. For a borehole pump, the quantity of water delivered would be used; and so on. What these examples all have in common is that on a weekly basis (say) numerical values can be recorded for each factor and one would expect particular streams of energy consumption to correlate with them either singly or in a multivariate model. Correlation is arguably more important than causality. Variation in the driving factor merely has to ''explain'' variation in consumption; it does not necessarily have t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Energy Monitoring And Targeting
Energy monitoring and targeting (M&T) is an energy efficiency technique based on the standard management axiom stating that “you cannot manage what you cannot measure”. M&T techniques provide energy managers with feedback on operating practices, results of energy management projects, and guidance on the level of energy use that is expected in a certain period. Importantly, they also give early warning of unexpected excess consumption caused by equipment malfunctions, operator error, unwanted user behaviours, lack of effective maintenance and the like. The foundation of M&T lies in determining the normal relationships of energy consumptions to relevant driving factors (HVAC equipment, production though puts, weather, occupancy available daylight, etc.) and the goal is to help business managers: * Identify and explain excessive energy use * Detect instances when consumption is unexpectedly higher or lower than would usually have been the case * Visualize energy consumption tren ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Energy Consumption
Energy consumption is the amount of energy used. Biology In the body, energy consumption is part of energy homeostasis. It derived from food energy. Energy consumption in the body is a product of the basal metabolic rate and the physical activity level. The physical activity level are defined for a non-pregnancy, pregnant, non-lactation, lactating adult as that person's total energy expenditure (TEE) in a 24-hour period, divided by his or her basal metabolic rate (BMR): :\text=\frac Demographics Topics related to energy consumption in a demographic sense are: * World energy supply and consumption * Domestic energy consumption * Electric energy consumption Effects of energy consumption * Environmental impact of the energy industry ** Global warming * White's law Reduction of energy consumption * Energy conservation, the practice of decreasing the quantity of energy used * Efficient energy use See also * Efficient energy use, Energy efficiency * Energy efficiency in transpor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dependent And Independent Variables
Dependent and independent variables are variables in mathematical modeling, statistical modeling and experimental sciences. Dependent variables receive this name because, in an experiment, their values are studied under the supposition or demand that they depend, by some law or rule (e.g., by a mathematical function), on the values of other variables. Independent variables, in turn, are not seen as depending on any other variable in the scope of the experiment in question. In this sense, some common independent variables are time, space, density, mass, fluid flow rate, and previous values of some observed value of interest (e.g. human population size) to predict future values (the dependent variable). Of the two, it is always the dependent variable whose variation is being studied, by altering inputs, also known as regressors in a statistical context. In an experiment, any variable that can be attributed a value without attributing a value to any other variable is called an in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synonym
A synonym is a word, morpheme, or phrase that means exactly or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are all synonyms of one another: they are ''synonymous''. The standard test for synonymy is substitution: one form can be replaced by another in a sentence without changing its meaning. Words are considered synonymous in only one particular sense: for example, ''long'' and ''extended'' in the context ''long time'' or ''extended time'' are synonymous, but ''long'' cannot be used in the phrase ''extended family''. Synonyms with exactly the same meaning share a seme or denotational sememe, whereas those with inexactly similar meanings share a broader denotational or connotational sememe and thus overlap within a semantic field. The former are sometimes called cognitive synonyms and the latter, near-synonyms, plesionyms or poecilonyms. Lexicograph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Degree Day
A degree day is a measure of heating or cooling. Total degree days from an appropriate starting date are used to plan the planting of crops and management of pests and pest control timing. Weekly or monthly degree-day figures may also be used within an energy monitoring and targeting scheme to monitor the heating and cooling costs of climate controlled buildings, while annual figures can be used for estimating future costs. A degree day is computed as the integral of a function of time that generally varies with temperature. The function is truncated to upper and lower limits that vary by organism, or to limits that are appropriate for climate control. The function can be estimated or measured by one of the following methods, in each case by reference to a chosen base temperature: * Frequent measurements and continuously integrating the temperature deficit or excess; * Treating each day's temperature profile as a sine wave with amplitude equal to the day's temperature variation, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Circuits
An electrical network is an interconnection of electrical components (e.g., batteries, resistors, inductors, capacitors, switches, transistors) or a model of such an interconnection, consisting of electrical elements (e.g., voltage sources, current sources, resistances, inductances, capacitances). An electrical circuit is a network consisting of a closed loop, giving a return path for the current. Linear electrical networks, a special type consisting only of sources (voltage or current), linear lumped elements (resistors, capacitors, inductors), and linear distributed elements (transmission lines), have the property that signals are linearly superimposable. They are thus more easily analyzed, using powerful frequency domain methods such as Laplace transforms, to determine DC response, AC response, and transient response. A resistive circuit is a circuit containing only resistors and ideal current and voltage sources. Analysis of resistive circuits is less complicated t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Outdoor Lighting
Landscape lighting or garden lighting refers to the use of outdoor illumination of private gardens and public landscapes; for the enhancement and purposes of safety, nighttime aesthetics, accessibility, security, recreation and sports, and social and event uses. Light pollution exacerbated by excessive, misdirected or obtrusive use of light, but even carefully used light fundamentally alters natural conditions. As a major side-effect of urbanization, it is blamed for compromising health, disrupting ecosystems and spoiling aesthetic environments. History The public landscape and gardens have been illuminated for as long as interior structures have – for beauty, security, circulation, and social occasions; since ancient times by firelight from wood, candles, and animal-plant oil fells in torches, sconces and lanterns. Since the 17th century's introductions of new interior illumination fuels, the technology has then been used outdoors and in gardens. As systems were developed f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Number
A number is a mathematical object used to count, measure, and label. The original examples are the natural numbers 1, 2, 3, 4, and so forth. Numbers can be represented in language with number words. More universally, individual numbers can be represented by symbols, called ''numerals''; for example, "5" is a numeral that represents the number five. As only a relatively small number of symbols can be memorized, basic numerals are commonly organized in a numeral system, which is an organized way to represent any number. The most common numeral system is the Hindu–Arabic numeral system, which allows for the representation of any number using a combination of ten fundamental numeric symbols, called digits. In addition to their use in counting and measuring, numerals are often used for labels (as with telephone numbers), for ordering (as with serial numbers), and for codes (as with ISBNs). In common usage, a ''numeral'' is not clearly distinguished from the ''number'' th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multivariate Statistics
Multivariate statistics is a subdivision of statistics encompassing the simultaneous observation and analysis of more than one outcome variable, i.e., ''multivariate random variables''. Multivariate statistics concerns understanding the different aims and background of each of the different forms of multivariate analysis, and how they relate to each other. The practical application of multivariate statistics to a particular problem may involve several types of univariate and multivariate analyses in order to understand the relationships between variables and their relevance to the problem being studied. In addition, multivariate statistics is concerned with multivariate probability distributions, in terms of both :*how these can be used to represent the distributions of observed data; :*how they can be used as part of statistical inference, particularly where several different quantities are of interest to the same analysis. Certain types of problems involving multivariate data ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Correlation And Dependence
In statistics, correlation or dependence is any statistical relationship, whether causal or not, between two random variables or bivariate data. Although in the broadest sense, "correlation" may indicate any type of association, in statistics it usually refers to the degree to which a pair of variables are ''linearly'' related. Familiar examples of dependent phenomena include the correlation between the height of parents and their offspring, and the correlation between the price of a good and the quantity the consumers are willing to purchase, as it is depicted in the so-called demand curve. Correlations are useful because they can indicate a predictive relationship that can be exploited in practice. For example, an electrical utility may produce less power on a mild day based on the correlation between electricity demand and weather. In this example, there is a causal relationship, because extreme weather causes people to use more electricity for heating or cooling. However ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Causality
Causality (also referred to as causation, or cause and effect) is influence by which one event, process, state, or object (''a'' ''cause'') contributes to the production of another event, process, state, or object (an ''effect'') where the cause is partly responsible for the effect, and the effect is partly dependent on the cause. In general, a process has many causes, which are also said to be ''causal factors'' for it, and all lie in its past. An effect can in turn be a cause of, or causal factor for, many other effects, which all lie in its future. Some writers have held that causality is metaphysically prior to notions of time and space. Causality is an abstraction that indicates how the world progresses. As such a basic concept, it is more apt as an explanation of other concepts of progression than as something to be explained by others more basic. The concept is like those of agency and efficacy. For this reason, a leap of intuition may be needed to grasp it. Accordin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scenario
In the performing arts, a scenario (, ; ; ) is a synoptical collage of an event or series of actions and events. In the ''commedia dell'arte'', it was an outline of entrances, exits, and action describing the plot of a play, and was literally pinned to the back of the scenery. It is also known as ''canovaccio'' or "that which is pinned to the canvas" of which the scenery was constructed. Surviving scenarios from the Renaissance contain little other than character names, brief descriptions of action, and references to specific lazzi with no further explanation. It is believed that a scenario formed the basis for a fully improvisational performance, though it is also likely that they were simple reminders of the plot for those members of the cast who were literate. Modern commedia troupes most often make use of a script with varying degrees of additional improvisation. In the creation of an opera or ballet, a scenario is often developed initially to indicate how the original sou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
