Computational physics

Numerical analysis · Simulation Data analysis · Visualization This article is about computer modeling within an artistic medium. ... This article is about emulators in computer science. ... Computational physics is the study and implementation of numerical algorithms in order to solve problems in physics for which a quantitative theory already exists. ... Image File history File links No higher resolution available. ... Numerical analysis is the study of approximate methods for the problems of continuous mathematics (as distinguished from discrete mathematics). ... Data analysis is the act of transforming data with the aim of extracting useful information and facilitating conclusions. ... A scientific visualization of an extremely large simulation of a Raleigh-Taylor instability caused by two mixing fluids. ... Fluid dynamics Finite element · Riemann solver Smoothed particle hydrodynamics A computer simulation of high velocity air flow around the Space Shuttle during re-entry. ... Visualization of how a car deforms in an asymmetrical crash using finite element analysis. ... Smoothed Particle Hydrodynamics (SPH) is a computational method used for simulating fluid flows. ... Monte Carlo methods Integration · Gibbs sampling · Metropolis algorithm Particle N-body · Particle-in-cell Molecular dynamics The Monte Carlo method can be illustrated as a game of battleship. ... This article describes multidimensional Monte Carlo integration. ... In mathematics and physics, Gibbs sampling is an algorithm to generate a sequence of samples from the joint probability distribution of two or more random variables. ... The Sampling distribution Q determines the next point to move to in the random walk. ... The n-body problem is the problem of finding, given the initial positions, masses, and velocities of n bodies, their subsequent motions as determined by classical mechanics, i. ... Particle-In-Cell (PIC) is an algorithm to compute (for example) the trajectories of charged particles in an electromagnetic field. ... Molecular dynamics (MD) is a form of computer simulation wherein atoms and molecules are allowed to interact for a period of time under known laws of physics, giving a view of the motion of the atoms. ... Scientists von Neumann · Godunov

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A computer simulation, a computer model or a computational model is a computer program, or network of computers, that attempts to simulate an abstract model of a particular system. Computer simulations have become a useful part of mathematical modelling of many natural systems in physics (computational physics), chemistry and biology, human systems in economics, psychology, and social science and in the process of engineering new technology, to gain insight into the operation of those systems, or to observe their behavior.^[1] For other persons named John Neumann, see John Neumann (disambiguation). ... Sergei Konstantinovich Godunov (b. ... A computer program is a collection of instructions that describe a task, or set of tasks, to be carried out by a computer. ... This article is about the general term. ... An abstract model (or conceptual model) is a theoretical construct that represents something, with a set of variables and a set of logical and quantitative relationships between them. ... A mathematical model uses mathematical language to describe a system. ... A magnet levitating above a high-temperature superconductor demonstrates the Meissner effect. ... Computational physics is the study and implementation of numerical algorithms in order to solve problems in physics for which a quantitative theory already exists. ... For other uses, see Chemistry (disambiguation). ... For other uses, see Biology (disambiguation). ... Face-to-face trading interactions on the New York Stock Exchange trading floor. ... Psychological science redirects here. ... The social sciences are groups of academic disciplines that study the human aspects of the world. ... Engineering is the discipline and profession of applying scientific knowledge and utilizing natural laws and physical resources in order to design and implement materials, structures, machines, devices, systems, and processes that realize a desired objective and meet specified criteria. ... By the mid 20th century humans had achieved a mastery of technology sufficient to leave the surface of the Earth for the first time and explore space. ...

Computer simulations vary from computer programs that run a few minutes, to network-based groups of computers running for hours, to ongoing simulations that run for days. The scale of events being simulated by computer simulations has far exceeded anything possible (or perhaps even imaginable) using the traditional paper-and-pencil mathematical modeling: over 10 years ago, a desert-battle simulation, of one force invading another, involved the modeling of 66,239 tanks, trucks and other vehicles on simulated terrain around Kuwait, using multiple supercomputers in the DoD High Performance Computer Modernization Program; ^[2] a 1-billion-atom model of material deformation (2002); a 2.64-million-atom model of the complex maker of protein in all organisms, a ribosome, in 2005;^[3] and the Blue Brain project at EPFL (Switzerland), began in May 2005, to create the first computer simulation of the entire human brain, right down to the molecular level. ^[4] Note: The term model is also given a formal meaning in model theory, a part of axiomatic set theory. ... The United States Department of Defense (DOD or DoD) is the federal department charged with coordinating and supervising all agencies and functions of the government relating directly to national security and the military. ... Figure 1: Ribosome structure indicating small subunit (A) and large subunit (B). ... Blue Brain is a project to begin the construction of a simulated brain. ... The Monster Clothespin from Outer Space, and entrance of the EPFL The École Polytechnique Fédérale de Lausanne (EPFL) is the Swiss Federal Institute of Technology in Lausanne in Switzerland. ...

Simulation versus modelling

Traditionally, the formal modelling, or modeling, of systems has been via a mathematical model, which attempts to find analytical solutions to problems which enables the prediction of the behaviour of the system from a set of parameters and initial conditions. A mathematical model uses mathematical language to describe a system. ... In mathematics, an equation or system of equations is said to have a closed-form solution if, and only if, at least one solution can be expressed analytically in terms of a bounded number of well-known operations. ...

While computer simulations might use some algorithms from purely mathematical models, computers can combine simulations with reality of actual events, such as generating input responses, to simulate test subjects who are no longer present. Whereas the missing test subjects are being modeled/simulated, the system they use could be the actual equipment, revealing performance limits or defects in long-term use by the simulated users.

Note that the term computer simulation is broader than computer modelling, which implies that all aspects are being modelled in the computer representation. However, computer simulation also includes generating inputs from simulated users to run actual computer software or equipment, with only part of the system being modelled: an example would be flight simulators which can run machines as well as actual flight software. For flight simulator software from Microsoft, see Microsoft Flight Simulator. ...

Computer simulations are used in many fields, including science, technology, entertainment, and business planning and scheduling. It also helps you work out what something will be like before it's finished. A magnet levitating above a high-temperature superconductor demonstrates the Meissner effect. ... By the mid 20th century humans had achieved a mastery of technology sufficient to leave the surface of the Earth for the first time and explore space. ... A stilt-walker entertaining shoppers at a shopping centre in Swindon, England Entertainment is an activity designed to give pleasure or relaxation to an audience (although in the case of a computer game the audience may be only one person). ... In economics, a business (also called firm or enterprise) is a legally recognized organizational entity designed to provide goods and/or services to consumers or corporate entities such as governments, charities or other businesses. ...

History

Computer simulation was developed hand-in-hand with the rapid growth of the computer, following its first large-scale deployment during the Manhattan Project in World War II to model the process of nuclear detonation. It was a simulation of 12 hard spheres using a Monte Carlo algorithm. Computer simulation is often used as an adjunct to, or substitution for, modeling systems for which simple closed form analytic solutions are not possible. There are many different types of computer simulation; the common feature they all share is the attempt to generate a sample of representative scenarios for a model in which a complete enumeration of all possible states of the model would be prohibitive or impossible. Computer models were initially used as a supplement for other arguments, but their use later became rather widespread. This article is about the World War II nuclear project. ... Combatants Allied powers: China France Great Britain Soviet Union United States and others Axis powers: Germany Italy Japan and others Commanders Chiang Kai-shek Charles de Gaulle Winston Churchill Joseph Stalin Franklin Roosevelt Adolf Hitler Benito Mussolini Hideki Tōjō Casualties Military dead: 17,000,000 Civilian dead: 33,000... The mushroom cloud of the atomic bombing of Nagasaki, Japan, 1945, rose some 18 kilometers (11 mi) above the hypocenter A nuclear weapon derives its destructive force from nuclear reactions of fusion or fission. ... Hard spheres are widely used as model particles in the statistical mechanical theory of fluids and solids. ... The Monte Carlo method can be illustrated as a game of battleship. ... In mathematics, an equation or system of equations is said to have a closed-form solution just in case a solution can be expressed analytically in terms of a bounded number of well_known operations. ...

Data preparation

The data input/output for the simulation can be either through formatted textfiles or a pre- and postprocessor. In Computer aided engineering (CAE) a preprocessor is a program which provides a Graphical user interface (GUI) to define physical properties. ...

Types

Computer models can be classified according to several criteria including:

• Stochastic or deterministic (and as a special case of deterministic, chaotic) - see External links below for examples of stochastic vs. deterministic simulations
• Steady-state or dynamic
• Continuous or discrete (and as an important special case of discrete, discrete event or DE models)
• Local or distributed.

For example: In the mathematics of probability, a stochastic process is a random function. ... In computer science, a deterministic algorithm is an algorithm which, in informal terms, behaves predictably. ... In mathematics, a continuous function is a function for which, intuitively, small changes in the input result in small changes in the output. ... Discrete mathematics, also called finite mathematics, is the study of mathematical structures that are fundamentally discrete, in the sense of not supporting or requiring the notion of continuity. ... In discrete event simulation, the operation of a system is represented as a chronological sequence of events. ... Distributed computing is a method of computer processing in which different parts of a program are run simultaneously on two or more computers that are communicating with each other over a network. ...

• Steady-state models use equations defining the relationships between elements of the modelled system and attempt to find a state in which the system is in equilibrium. Such models are often used in simulating physical systems, as a simpler modelling case before dynamic simulation is attempted.
• Dynamic simulations model changes in a system in response to (usually changing) input signals.
• Stochastic models use random number generators to model chance or random events; they are also called Monte Carlo simulations.
• A discrete event simulation (DES) manages events in time. Most computer, logic-test and fault-tree simulations are of this type. In this type of simulation, the simulator maintains a queue of events sorted by the simulated time they should occur. The simulator reads the queue and triggers new events as each event is processed. It is not important to execute the simulation in real time. It's often more important to be able to access the data produced by the simulation, to discover logic defects in the design, or the sequence of events.
• A continuous dynamic simulation performs numerical solution of differential-algebraic equations or differential equations (either partial or ordinary). Periodically, the simulation program solves all the equations, and uses the numbers to change the state and output of the simulation. Applications include flight simulators, construction and management simulation games, chemical process modeling, and simulations of electrical circuits. Originally, these kinds of simulations were actually implemented on analog computers, where the differential equations could be represented directly by various electrical components such as op-amps. By the late 1980s, however, most "analog" simulations were run on conventional digital computers that emulate the behavior of an analog computer.
• A special type of discrete simulation which does not rely on a model with an underlying equation, but can nonetheless be represented formally, is agent-based simulation. In agent-based simulation, the individual entities (such as molecules, cells, trees or consumers) in the model are represented directly (rather than by their density or concentration) and possess an internal state and set of behaviors or rules which determine how the agent's state is updated from one time-step to the next.
• distributed models run on a network of interconnected computers, possibly through the Internet. Simulations dispersed across multiple host computers like this are often referred to as "distributed simulations". There are several standards for distributed simulation, including Aggregate Level Simulation Protocol (ALSP), Distributed Interactive Simulation (DIS), the High Level Architecture (simulation) (HLA) and the Test and Training Enabling Architecture (TENA).

In the mathematics of probability, a stochastic process is a random function. ... A random number generator is a computational or physical device designed to generate a sequence of elements (usually numbers), such that the sequence can be used as a random one. ... The Monte Carlo method can be illustrated as a game of battleship. ... In discrete event simulation, the operation of a system is represented as a chronological sequence of events. ... Differential algabraic equations (DAEs) are a generalised form of Differential equation. ... In mathematics, a differential equation is an equation in which the derivatives of a function appear as variables. ... In mathematics, a partial differential equation (PDE) is a relation involving an unknown function of several independent variables and its partial derivatives with respect to those variables. ... In mathematics, an ordinary differential equation (or ODE) is a relation that contains functions of only one independent variable, and one or more of its derivatives with respect to that variable. ... Construction and management simulation games (or CMSs)[1] are a type of simulation game which task players to build, expand or manage fictional communities or projects with limited resources. ... Chemical process modelling is a computer modeling technique used in chemical engineering process design. ... An electrical network or electrical circuit is an interconnection of analog electrical elements such as resistors, inductors, capacitors, diodes, switches and transistors. ... A page from the Bombardiers Information File (BIF) that describes the components and controls of the Norden bombsight. ... An operational amplifier or op-amp is an electronic circuit module (normally built as an integrated circuit, but occasionally with discrete transistors or vacuum tubes) which has a non-inverting input (+), an inverting input (-) and one output. ... The 1980s was the decade spanning from 1980 to 1989, also called The Eighties. The decade saw social, economic and general upheaval as wealth, production and western culture migrated to new industrializing economies. ... ... This article is about emulation in computer science. ... Distributed computing is a method of computer processing in which different parts of a program are run simultaneously on two or more computers that are communicating with each other over a network. ... Distributed Interactive Simulation (DIS) is a standard for conducting real-time platform-level wargaming across multiple host computers. ...

CGI computer simulation

Formerly, the output data from a computer simulation was sometimes presented in a table, or a matrix, showing how data was affected by numerous changes in the simulation parameters. The use of the matrix format was related to traditional use of the matrix concept in mathematical models; however, psychologists and others noted that humans could quickly perceive trends by looking at graphs or even moving-images or motion-pictures generated from the data, as displayed by computer-generated-imagery (CGI) animation. Although observers couldn't necessarily read out numbers, or spout math formulas, from observing a moving weather chart, they might be able to predict events (and "see that rain was headed their way"), much faster than scanning tables of rain-cloud coordinates. Such intense graphical displays, which transcended the world of numbers and formulae, sometimes also led to output that lacked a coordinate grid or omitted timestamps, as if straying too far from numeric data displays. Today, weather forecasting models tend to balance the view of moving rain/snow clouds against a map that uses numeric coordinates and numeric timestamps of events. A mathematical model uses mathematical language to describe a system. ... The seawater creature in The Abyss marked CGIs acceptance in the visual effects industry. ... See Cartesian coordinate system or Coordinates (elementary mathematics) for a more elementary introduction to this topic. ... Modern weather predictions aid in timely evacuations and potentially save lives and property damage Human beings have attempted to predict the weather since time immemorial. ...

Similarly, CGI computer simulations of CAT scans can simulate how a tumor might shrink or change, during an extended period of medical treatment, presenting the passage of time as a spinning view of the visible human head, as the tumor changes. CAT apparatus in a hospital Computed axial tomography (CAT), computer-assisted tomography, computed tomography, CT, or body section roentgenography is the process of using digital processing to generate a three-dimensional image of the internals of an object from a large series of two-dimensional X-ray images taken around... A brain tumor is any mass created by an abnormal and uncontrolled growth of cells either found in the brain (neurons, glial cells, epithelial cells, myelin producing cells, etc. ...

Other applications of CGI computer simulations are being developed to graphically display large amounts of data, in motion, as changes occur during a simulation run.

Computer simulation in science

Generic examples of types of computer simulations in science, which are derived from an underlying mathematical description:

• a numerical simulation of differential equations which cannot be solved analytically, theories which involve continuous systems such as phenomena in physical cosmology, fluid dynamics (e.g. climate models, roadway noise models, roadway air dispersion models), continuum mechanics and chemical kinetics fall into this category.
• a stochastic simulation, typically used for discrete systems where events occur probabilistically, and which cannot be described directly with differential equations (this is a discrete simulation in the above sense). Phenomena in this category include genetic drift, biochemical or gene regulatory networks with small numbers of molecules. (see also: Monte Carlo method).

Specific examples of computer simulations follow: Visualization of airflow into a duct modelled using the Navier-Stokes equations, a set of partial differential equations. ... This article is about the physics subject. ... --68. ... Climate models use quantitative methods to simulate the interactions of the atmosphere, oceans, land surface, and ice. ... Roadway noise is the most prevalent form of environmental noise. ... Roadway air dispersion is applied to highway segments Roadway air dispersion modeling is the study of air pollutant transport from a roadway or other linear emitter. ... Continuum mechanics is a branch of physics (specifically mechanics) that deals with continuous matter, including both solids and fluids (i. ... In physical chemistry, chemical kinetics or reaction kinetics is the study of reaction rates in a chemical reaction. ... Stochastic, from the Greek stochos or goal, means of, relating to, or characterized by conjecture; conjectural; random. ... The word probability derives from the Latin probare (to prove, or to test). ... In population genetics, genetic drift is the statistical effect that results from the influence that chance has on the success of alleles (variants of a gene). ... Wöhler observes the synthesis of urea. ... A gene regulatory network (also called a GRN or genetic regulatory network) is a collection of DNA segments in a cell which interact with each other (indirectly through their RNA and protein expression products) and with other substances in the cell, thereby governing the rates at which genes in the... The Monte Carlo method can be illustrated as a game of battleship. ...

• statistical simulations based upon an agglomeration of a large number of input profiles, such as the forecasting of equilibrium temperature of receiving waters, allowing the gamut of meteorological data to be input for a specific locale. This technique was developed for thermal pollution forecasting .

• agent based simulation has been used effectively in ecology, where it is often called individual based modeling and has been used in situations for which individual variability in the agents cannot be neglected, such as population dynamics of salmon and trout (most purely mathematical models assume all trout behave identically).

• time stepped dynamic model. In hydrology there are several such hydrology transport models such as the SWMM and DSSAM Models developed by the U.S. Environmental Protection Agency for river water quality forecasting.

• computer simulations have also been used to formally model theories of human cognition and performance, e.g. ACT-R

• computer simulation using molecular modelling for drug discovery

• Computational fluid dynamics simulations are used to simulate the behaviour of flowing air, water and other fluids. There are one-, two- and three- dimensional models used. A one dimensional model might simulate the effects of water hammer in a pipe. A two-dimensional model might be used to simulate the drag forces on the cross-section of an aeroplane wing. A three-dimensional simulation might estimate the heating and cooling requirements of a large building.

• An understanding of statistical thermodynamic molecular theory is fundamental to the appreciation of molecular solutions. Development of the Potential Distribution Theorem (PDT) allows one to simplify this complex subject to down-to-earth presentations of molecular theory.

Notable, and sometimes controversial, computer simulations used in science include: Donella Meadows' World3 used in the Limits to Growth, James Lovelock's Daisyworld and Thomas Ray's Tierra. For other uses, see Temperature (disambiguation). ... Meteorology is the scientific study of the atmosphere that focuses on weather processes and forecasting. ... Thermal pollution is a temperature change in natural water bodies caused by human influence. ... For the journal, see Ecology (journal). ... Population dynamics is the study of marginal and long-term changes in the numbers, individual weights and age composition of individuals in one or several populations, and biological and environmental processes influencing those changes. ... For other uses, see Salmon (disambiguation). ... For other uses, see Trout (disambiguation). ... River in Madagascar relatively free of sediment load An hydrological transport model is a mathematical model used to simulate river or stream flow and calculate water quality parameters. ... The US Environment Protection Agency Storm Water Management Model (SWMM) is a dynamic rainfall-runoff simulation model used for single event or long-term (continuous) simulation of runoff quantity and quality from primarily urban areas. ... Lake Tahoe, headwater sub-basin of the Truckee River watershed The DSSAM Model (Dynamic Stream Simulation and Assessment. ... EPA redirects here. ... ACT-R (pronounced act-ARE: Adaptive Control of Thought--Rational) is a cognitive architecture mainly developed by John R. Anderson at Carnegie Mellon University. ... The backbone dihedral angles are included in the molecular model of a protein. ... In medicine, biotechnology and pharmacology, drug discovery is the process by which drugs are discovered and/or designed. ... A computer simulation of high velocity air flow around the Space Shuttle during re-entry. ... Water hammer (or, more generally, fluid hammer) is a pressure surge or wave caused by the kinetic energy of a fluid in motion when it is forced to stop or change direction suddenly. ... Donella Dana Meadows (March 13, 1941 Elgin, Illinois, USA - February 20, 2001, New Hampshire) was a pioneering environmental scientist, a teacher and writer. ... The World3 model was a computer simulation of interactions between population, industrial growth, food production and limits in the ecosystems of the Earth. ... Limits to Growth was a 1972 book modeling the consequences of a rapidly growing world population and finite resource supplies, commissioned by the Club of Rome. ... Dr. James Ephraim Lovelock, CH, CBE, FRS (born 26 July 1919) is an independent scientist, author, researcher, environmentalist, and futurologist who lives in Cornwall, in the south west of Great Britain. ... Daisyworld, a computer simulation, is a hypothetical world orbiting a sun whose temperature is slowly increasing in the simulation. ... Tierra is a computer simulation developed by ecologist Thomas S. Ray in the early 1990s in which computer programs compete for central processing unit (CPU) time and access to main memory. ...

Simulation environments for physics and engineering

Graphical environments to design simulations have been developed. Special care was taken to handle events (situations in which the simulation equations are not valid and have to be changed). The open project Open Source Physics was started to develop reusable libraries for simulations in Java, together with Easy Java Simulations, a complete graphical environment that generates code based on these libraries.

Computer simulation in practical contexts

Computer simulations are used in a wide variety of practical contexts, such as:

• analysis of air pollutant dispersion using atmospheric dispersion modeling
• design of complex systems such as aircraft and also logistics systems.
• design of Noise barriers to effect roadway noise mitigation
• flight simulators to train pilots
• weather forecasting
• behavior of structures (such as buildings and industrial parts) under stress and other conditions
• design of industrial processes, such as chemical processing plants
• Strategic Management and Organizational Studies
• Reservoir simulation for the petroleum engineering to model the subsurface reservoir
• Process Engineering Simulation tools.
• Robot simulators for the design of robots and robot control algorithms
• Traffic engineering to plan or redesign parts of the street network from single junctions over cities to a national highway network, see for example VISSIM.

The reliability and the trust people put in computer simulations depends on the validity of the simulation model, therefore verification and validation are of crucial importance in the development of computer simulations. Another important aspect of computer simulations is that of reproducibility of the results, meaning that a simulation model should not provide a different answer for each execution. Although this might seem obvious, this is a special point of attention in stochastic simulations, where random numbers should actually be semi-random numbers. An exception to reproducibility are human in the loop simulations such as flight simulations and computer games. Here a human is part of the simulation and thus influences the outcome in a way that is hard if not impossible to reproduce exactly. This power plant in New Mexico releases sulfur dioxide and particulate matter into the air. ... Atmospheric dispersion modeling is performed with computer programs that use mathematical equations and algorithms to simulate how pollutants in the ambient atmosphere disperse in the atmosphere. ... Flying machine redirects here. ... Look up Logistics in Wiktionary, the free dictionary. ... The sound tube in Melbourne, Australia, designed to reduce roadway noise without detracting from the areas aesthetics. ... Noise mitigation is a set of strategies to reduce unwanted environmental sound. ... For flight simulator software from Microsoft, see Microsoft Flight Simulator. ... Modern weather predictions aid in timely evacuations and potentially save lives and property damage Human beings have attempted to predict the weather since time immemorial. ... Strategic management is the art and science of formulating, implementing and evaluating cross-functional decisions that will enable an organization to achieve its objectives[1]. It is the process of specifying the organizations objectives, developing policies and plans to achieve these objectives, and allocating resources to implement the policies... Organizational studies, organizational behavior, and organizational theory are related terms for the academic study of organizations, examining them using the methods of economics, sociology, political science, anthropology, communication studies, and psychology. ... Reservoir simulation is an area of reservoir engineering in which computer models are used to predict the flow of fluids (typically, oil, water, and gas) through porous media. ... It has been suggested that Player Project and Microsoft Robotics Studio be merged into this article or section. ... The term traffic engineering is used in more than one sense. ... VisSim is a visual block diagram language for modeling, simulating and analyzing dynamic systems. ... In logic, the form of an argument is valid precisely if it cannot lead from true premises to a false conclusion. ... An abstract model (or conceptual model) is a theoretical construct that represents something, with a set of variables and a set of logical and quantitative relationships between them. ... In the context of hardware and software systems, formal verification is the act of proving or disproving the correctness of a system with respect to a certain formal specification or property, using formal methods. ... The word validation has several uses: In general, validation is the process of checking if something satisfies a certain criterion. ... This article needs a complete rewrite for the reasons listed on the talk page. ...

Computer graphics can be used to display the results of a computer simulation. Animations can be used to experience a simulation in real-time e.g. in training simulations. In some cases animations may also be useful in faster than real-time or even slower than real-time modes. For example, faster than real-time animations can be useful in visualizing the buildup of queues in the simulation of humans evacuating a building. Furthermore, simulation results are often aggregated into static images using various ways of scientific visualization. This article is about the scientific discipline of computer graphics. ... Animation refers to the process in which each frame of a film or movie is produced individually, whether generated as a computer graphic, or by photographing a drawn image, or by repeatedly making small changes to a model (see claymation and stop motion), and then photographing the result. ... A scientific visualization of an extremely large simulation of a Raleigh-Taylor instability caused by two mixing fluids. ...

In debugging, simulating a program execution under test (rather than executing natively) can detect far more errors than the hardware itself can detect and, at the same time, log useful debugging information such as instruction trace, memory alterations and instruction counts. This technique can also detect buffer overflow and similar "hard to detect" errors as well as produce performance information and tuning data. [[Media:Media:Example. ... In music, tuning is the process of producing or preparing to produce a certain pitch in relation to another, usually at the unison but often at some other interval. ...

Pitfalls

Although sometimes ignored in computer simulations, it is very important to perform sensitivity analysis to ensure that the accuracy of the results are properly understood. For example, the probabilistic risk analysis of factors determining the success of an oilfield exploration program involves combining samples from a variety of statistical distributions using the Monte Carlo method. If, for instance, one of the key parameters (i.e. the net ratio of oil-bearing strata) is known to only one significant figure, then the result of the simulation might not be more precise than one significant figure, although it might (misleadingly) be presented as having four significant figures. It has been suggested that What-if analysis be merged into this article or section. ... The Monte Carlo method can be illustrated as a game of battleship. ...

See also

• ACT-R
• Articulatory synthesis
• Artificial life
• CAVE
• Computer-aided design
• Computer simulation and organizational studies
• Dry Lab
• Earth Simulator
• Emulator
• Experiment in silico
• List of computer simulation software
• Mathematical model
• Molecular dynamics
• Simcyp Simulator
• Simulated reality
• Social simulation

ACT-R (pronounced act-ARE: Adaptive Control of Thought--Rational) is a cognitive architecture mainly developed by John R. Anderson at Carnegie Mellon University. ... Articulatory synthesis refers to computational techniques for synthesizing speech based on models of the human vocal tract and the articulation processes occurring there. ... This article is about a field of research. ... A Cave Automatic Virtual Environment (better known by the recursive acronym CAVE) is an immersive virtual reality environment where projectors are directed to four, five or six of the walls of a room-sized cube. ... CADD and CAD redirect here. ... Computer Simulation is a prominent method in organizational studies and strategic management. ... A dry lab is a laboratory where computational or applied mathematical analyses are done on a computer generated model to simulate a phenomenon in the physical realm whether it be a molecule changing quantum states, the event horizon of a black hole or anything that otherwise might be too cumbersome... The Earth Simulator (ES) was the fastest supercomputer in the world from 2002 to 2004. ... This article is about emulators in computer science. ... In Silico is a full length artist album by Deepsky View From a Stairway Jareths Church The Mansion World (Deepskys Trippin In Unknown Territory Mix) Ride Three Sheets to the Wind Atia Metro Smile Cosmic Dancer (2002 remix) Until the End of the World Let Me Live Categories... See Computer simulation ASCEND (open source NLA/DAE modelling environment) Computational Infrastructure for Operations Research (free open-source Operations Research code) Facsimile an open-source discrete-event simulation/emulation library for . ... A mathematical model uses mathematical language to describe a system. ... Molecular dynamics (MD) is a form of computer simulation wherein atoms and molecules are allowed to interact for a period of time under known laws of physics, giving a view of the motion of the atoms. ... Simulated reality is the idea that reality could be simulated — often computer-simulated — to a degree indistinguishable from true reality. ... Social simulation is the modelling, or simulation, normally performed using a computer, of social phenomena (e. ...

External links

Organizations

• EUROSIM - Federation of European Simulation Societies
• Institute for Simulation and Training, University of Central Florida
• Simulation Interoperability Standards Organization
• The Society for Modeling and Simulation International (Formerly the Society of Computer Simulation)
• United States Defense Modeling and Simulation Office
• The System Dynamics Society
• The Computational Modelling Group at Cambridge University's Department of Chemical Engineering
• Liophant Simulation
• United Simulation Team - Genoa University

Education

• Simulation-An Enabling Technology in Software Engineering
• Sabanci University School of Languages Podcasts: Computer Simulation by Prof. David M. Goldsman
• IMTEK Mathematica Supplement (IMS) (some Mathematica-specific tutorials here)
• The Creative Learning Exchange
• McLeod Institute of Simulation Science

Examples

• A portfolio of free public simulations from the University of Florida
• Integrated Land Use, Transportation, Environment, (ILUTE) Modeling System
• Nanorobotics Simulation - Computational Nanomechatronics Lab. at Center for Automation in Nanobiotech (CAN)
• Online traffic simulation
• Shakemovie Caltech's Online Seismic Event Simulation
• Global Politics Simulation
• Industrial & Educational Examples of Modelling & Simulation
• Matlab SUrrogate MOdeling Toolbox - SUMO Toolbox - Matlab code for Surrogate Simulation Models
• Generalized online simulation utility

References

This article or section, while providing some complete reference citations, includes a list of references or external links, and its verifiability remains partly unclear because it has insufficient in-text citations. You can improve this article by introducing more precise citations.

• R. Frigg and S. Hartmann, Models in Science. Entry in the Stanford Encyclopedia of Philosophy.
• S. Hartmann, The World as a Process: Simulations in the Natural and Social Sciences, in: R. Hegselmann et al. (eds.), Modelling and Simulation in the Social Sciences from the Philosophy of Science Point of View, Theory and Decision Library. Dordrecht: Kluwer 1996, 77-100.
• P. Humphreys, Extending Ourselves: Computational Science, Empiricism, and Scientific Method. Oxford: Oxford University Press, 2004.