“model”的概念、定义、翻译、参考文献-科学参考

model

Physics

A simplified description of a physical system intended to capture the essential aspects of the system in a sufficiently simple form to enable the mathematics to be solved. In practice some models require approximation techniques to be used, rather than being exactly soluble. When exact solutions are available they can be used to examine the validity of the approximation techniques.

Mathematics

See mathematical model.

Statistics

A simple description of a probabilistic process that may have given rise to observed data. For example, if the data consist of the numbers shown by a fair die during a game of Snakes and Ladders, then a simple model would state that for each roll, and independent of the outcomes of other rolls, the distribution of the number shown is a discrete uniform distribution, on 1, 2,…, 6.
Models form the bedrock of Statistics. Specific distributions are often invoked. Many types of models are mentioned in this dictionary.

Chemistry

A representation of a physical or chemical system that is a simplification of the real system but which attempts to retain most of the key features of that system. The simplifications make mathematical analysis of the model easier than is the case in the real system and sometimes enable exact solutions to be obtained.

Chemical Engineering

A mathematical representation of a system or process using equations that predict its behaviour. See mathematical model.

Computer

A simplified representation of something (the referent). The representation may be physical or abstract, and may be restricted to certain properties of the referent. In computing, models are usually abstract and are typically represented in a diagramming notation, such as dataflow diagrams (in functional design), ERA diagrams (for a data model), or state-transition diagrams (for a model of behaviour); in the case of the relational model the referent is the target system while in the waterfall model, V-model, and spiral model the referent is the development process. In computer graphics, models are used to create realistic images of objects and their attributes (see colour model, lighting model, reflectance model).

Electronics and Electrical Engineering

A high-level description of a system in which unnecessary detail has been removed to ensure that the important aspects are as clear as possible. In practice there may be a number of different system models that emphasize different aspects of the system’s behaviour. Physical behaviour can be modelled using differential equations, Fourier transforms, and Laplace transforms. Computational behaviour can be captured using state diagrams.

Geology and Earth Sciences

Representation of reality in which the main features of some aspect of the real world are presented in simplified terms in order to make that aspect easier to comprehend, and often to facilitate the making of predictions.

Geography

A representation of some phenomenon of the real world made in order to facilitate an understanding of its workings. A model is a simplified and generalized version of real events, from which the incidental detail, or ‘noise’, has been removed; an ‘abstraction of an object, system or process that permits knowledge to be gained about reality by conducting experiments on the model’ (Clarke in P. Atkinson et al., eds 2004). Malmberg (1992, Geografiska B 74, 2) defines idealist models as ‘designations of theories that lack a specification of how this model is related to processes in time and space’.
In the 1960s, the quantitative revolution in geography saw an emphasis on models: basic mathematical equations and models, such as gravity models, deterministic models, such as von Thünens and Weber’s location models, and stochastic models that use probability. The ‘cultural’ turn—the counter-positivist response from human geography—stressed the weaknesses of models. O’Sullivan (2004) TIBG 29, 3 writes of geocomputational modelling, that ‘the compositional model represents a theory about the world, rather than the world itself. The end result is a model…whose behaviour may be almost as intractably difficult to account for as the world it represents’. Connecting the model back to the world it represents is difficult for a number of reasons, principally the equifinality problem, which makes it impossible to judge the relative merits of alternative models on purely technical grounds.
In physical geography, the basic requirement of a model is that it includes the important phenomena controlling a system, yet is restricted in complexity. One solution is to use a lumped model, which is constructed using average or ‘lumped’ representation of the relevant phenomena. Thus a lumped model of a catchment area would assume that catchment is homogeneous, by using representative soil properties and precipitation inputs. All this is reasonably clearly set out in Maurer et al. (2010) J. Amer. Water Res. Ass. 46, 5, 1024. Or try V. P. Singh, M. Fiorentino, eds (1996), section 10.2.1.

Philosophy

A representation of one system by another, usually more familiar, whose workings are supposed analogous to that of the first. Thus one might model the behaviour of sound waves upon that of waves in water, or the behaviour of a gas upon that of a volume containing moving billiard balls. Whilst nobody doubts that models have a useful heuristic role in science, there has been intense debate over whether a good explanation of some phenomenon needs a model, or whether an organized structure of laws from which it can be deduced suffices for scientific explanation. The debate was inaugurated by Duhem in his The Aim and Structure of Physical Theory (1906), which attacked the ‘shallow’ pictorial imaginings of British physicists, contrasting them with the pure deductive structures of proper science. Models often represent simplifications and idealizations (perfect gases, frictionless planes, perfectly elastic collisions) and even while fertile and useful can be approximations to more complex real phenomena.
In logic, a model for a set of sentences is an interpretation under which they are all true. See also model theory.

Economics

A simplified system used to simulate some aspects of the real economy. Models are used in economics because there are limited possibilities for experimentation and past experience does not always provide an answer. A model is a simplified description of the economy, or the part of the economy, relevant for the analysis. Economic models are distinguished from those in the natural sciences by the incorporation of independent decision-making by firms, consumers, and the politicians and bureaucrats who constitute government. These economic agents do not respond mechanically but are motivated by personal objectives and are strategic in their behaviour. Capturing the implications of this complex behaviour in a convincing manner is the key attribute of a successful economic model.

单词	model
释义	model Physics A simplified description of a physical system intended to capture the essential aspects of the system in a sufficiently simple form to enable the mathematics to be solved. In practice some models require approximation techniques to be used, rather than being exactly soluble. When exact solutions are available they can be used to examine the validity of the approximation techniques. Mathematics See mathematical model. Statistics A simple description of a probabilistic process that may have given rise to observed data. For example, if the data consist of the numbers shown by a fair die during a game of Snakes and Ladders, then a simple model would state that for each roll, and independent of the outcomes of other rolls, the distribution of the number shown is a discrete uniform distribution, on 1, 2,…, 6. Models form the bedrock of Statistics. Specific distributions are often invoked. Many types of models are mentioned in this dictionary. Chemistry A representation of a physical or chemical system that is a simplification of the real system but which attempts to retain most of the key features of that system. The simplifications make mathematical analysis of the model easier than is the case in the real system and sometimes enable exact solutions to be obtained. Chemical Engineering A mathematical representation of a system or process using equations that predict its behaviour. See mathematical model. Computer A simplified representation of something (the referent). The representation may be physical or abstract, and may be restricted to certain properties of the referent. In computing, models are usually abstract and are typically represented in a diagramming notation, such as dataflow diagrams (in functional design), ERA diagrams (for a data model), or state-transition diagrams (for a model of behaviour); in the case of the relational model the referent is the target system while in the waterfall model, V-model, and spiral model the referent is the development process. In computer graphics, models are used to create realistic images of objects and their attributes (see colour model, lighting model, reflectance model). Electronics and Electrical Engineering A high-level description of a system in which unnecessary detail has been removed to ensure that the important aspects are as clear as possible. In practice there may be a number of different system models that emphasize different aspects of the system’s behaviour. Physical behaviour can be modelled using differential equations, Fourier transforms, and Laplace transforms. Computational behaviour can be captured using state diagrams. Geology and Earth Sciences Representation of reality in which the main features of some aspect of the real world are presented in simplified terms in order to make that aspect easier to comprehend, and often to facilitate the making of predictions. Geography A representation of some phenomenon of the real world made in order to facilitate an understanding of its workings. A model is a simplified and generalized version of real events, from which the incidental detail, or ‘noise’, has been removed; an ‘abstraction of an object, system or process that permits knowledge to be gained about reality by conducting experiments on the model’ (Clarke in P. Atkinson et al., eds 2004). Malmberg (1992, Geografiska B 74, 2) defines idealist models as ‘designations of theories that lack a specification of how this model is related to processes in time and space’. In the 1960s, the quantitative revolution in geography saw an emphasis on models: basic mathematical equations and models, such as gravity models, deterministic models, such as von Thünens and Weber’s location models, and stochastic models that use probability. The ‘cultural’ turn—the counter-positivist response from human geography—stressed the weaknesses of models. O’Sullivan (2004) TIBG 29, 3 writes of geocomputational modelling, that ‘the compositional model represents a theory about the world, rather than the world itself. The end result is a model…whose behaviour may be almost as intractably difficult to account for as the world it represents’. Connecting the model back to the world it represents is difficult for a number of reasons, principally the equifinality problem, which makes it impossible to judge the relative merits of alternative models on purely technical grounds. In physical geography, the basic requirement of a model is that it includes the important phenomena controlling a system, yet is restricted in complexity. One solution is to use a lumped model, which is constructed using average or ‘lumped’ representation of the relevant phenomena. Thus a lumped model of a catchment area would assume that catchment is homogeneous, by using representative soil properties and precipitation inputs. All this is reasonably clearly set out in Maurer et al. (2010) J. Amer. Water Res. Ass. 46, 5, 1024. Or try V. P. Singh, M. Fiorentino, eds (1996), section 10.2.1. Philosophy A representation of one system by another, usually more familiar, whose workings are supposed analogous to that of the first. Thus one might model the behaviour of sound waves upon that of waves in water, or the behaviour of a gas upon that of a volume containing moving billiard balls. Whilst nobody doubts that models have a useful heuristic role in science, there has been intense debate over whether a good explanation of some phenomenon needs a model, or whether an organized structure of laws from which it can be deduced suffices for scientific explanation. The debate was inaugurated by Duhem in his The Aim and Structure of Physical Theory (1906), which attacked the ‘shallow’ pictorial imaginings of British physicists, contrasting them with the pure deductive structures of proper science. Models often represent simplifications and idealizations (perfect gases, frictionless planes, perfectly elastic collisions) and even while fertile and useful can be approximations to more complex real phenomena. In logic, a model for a set of sentences is an interpretation under which they are all true. See also model theory. Economics A simplified system used to simulate some aspects of the real economy. Models are used in economics because there are limited possibilities for experimentation and past experience does not always provide an answer. A model is a simplified description of the economy, or the part of the economy, relevant for the analysis. Economic models are distinguished from those in the natural sciences by the incorporation of independent decision-making by firms, consumers, and the politicians and bureaucrats who constitute government. These economic agents do not respond mechanically but are motivated by personal objectives and are strategic in their behaviour. Capturing the implications of this complex behaviour in a convincing manner is the key attribute of a successful economic model.
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