Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Simulation

Discipline
Institution
Publication Year
Publication
Publication Type
File Type

Articles 751 - 780 of 784

Full-Text Articles in Physical Sciences and Mathematics

Optimal Pulsed Pumping For Remediation Of Aquifers When Sorption Is Rate-Limited, Lawrence J. Schmitt Dec 1997

Optimal Pulsed Pumping For Remediation Of Aquifers When Sorption Is Rate-Limited, Lawrence J. Schmitt

Theses and Dissertations

A variational optimization technique is developed to acquire an optimal schedule of pulsed pumping operations for use at existing pump-and-treat aquifer remediation sites. The optimization problem is stated as a minimization of a generic management objective functional, constrained by the contaminant transport equations in two-dimensional or three-dimensional flow models which account for rate-limited sorption. The two-dimensional case is fully developed and a first-order rate equation is used to describe the transport of sorbing contaminant. The first variation provides necessary optimality conditions that must be met by any optimal solution, in turn leading to a pulsed pumping schedule of operation. The …


Visualization And Animation Of A Missile/Target Encounter, Jeffrey T. Bush Dec 1997

Visualization And Animation Of A Missile/Target Encounter, Jeffrey T. Bush

Theses and Dissertations

Existing missile/target encounter modeling and simulation systems focus on improving probability of kill models. Little research has been done to visualize these encounters. These systems can be made more useful to the engineers by incorporating current computer graphics technology for visualizing and animating the encounter. Our research has been to develop a graphical simulation package for visualizing both endgame and full fly-out encounters. Endgame visualization includes showing the interaction of a missile, its fuze cone proximity sensors, and its target during the final fraction of a second of the missile/target encounter. Additionally, this system displays dynamic effects such as the …


A Single Chip Low Power Implementation Of An Asynchronous Fft Algorithm For Space Applications, Bruce W. Hunt Dec 1997

A Single Chip Low Power Implementation Of An Asynchronous Fft Algorithm For Space Applications, Bruce W. Hunt

Theses and Dissertations

A fully asynchronous fixed point FFT processor is introduced for low power space applications. The architecture is based on an algorithm developed by Suter and Stevens specifically for a low power implementation. The novelty of this architecture lies in its high localization of components and pipelining with no need to share a global memory. High throughput is attained using large numbers of small, local components working in parallel. A derivation of the algorithm from the discrete Fourier transform is presented followed by a discussion of circuit design parameters specifically, those relevant to space applications. The generic architecture is explained with …


Java For Parallel Computing And As A General Language For Scientific And Engineering Simulation And Modeling, Geoffrey C. Fox, Wojtek Furmanski Jan 1997

Java For Parallel Computing And As A General Language For Scientific And Engineering Simulation And Modeling, Geoffrey C. Fox, Wojtek Furmanski

Northeast Parallel Architecture Center

We discuss the role of Java and Web technologies for general simulation. We classify the classes of concurrency typical in problems and analyze separately the role of Java in user interfaces, coarse grain software integration, and detailed computational kernels. We conclude that Java could become a major language for computational science, as it potentially offers good performance, excellent user interfaces, and the advantages of object-oriented structure.


Evaluation Of The Crop Growth Component Of The Root Zone Water Quality Model For Corn In Ohio, Sue E. Nokes, Feliks M. Landa, Jon D. Hanson Jan 1996

Evaluation Of The Crop Growth Component Of The Root Zone Water Quality Model For Corn In Ohio, Sue E. Nokes, Feliks M. Landa, Jon D. Hanson

Biosystems and Agricultural Engineering Faculty Publications

The Root Zone Water Quality Model (RZWQM) is a computer model developed to simulate water, chemical, and biological processes in the root zone of agricultural management systems. As of this writing RZWQM is in the beta-testing phase of development. This article reports on a parameterization and evaluation study performed in Ohio on field corn for the crop growth component of RZWQM. The generic crop growth model in RZWQM had not previously been parameterized or tested on field corn. This article reports the results of such a study. One year of data was used to calibrate RZWQM, and two additional years …


Simulations Between Programs As Cellular Automata, Howard A. Blair, Fred Dushin, Polar Humenn Dec 1995

Simulations Between Programs As Cellular Automata, Howard A. Blair, Fred Dushin, Polar Humenn

Electrical Engineering and Computer Science - Technical Reports

We present cellular automata on appropriate digraphs and show that any covered normal logic program is a cellular automaton. Seeing programs as cellular automata shifts attention from classes of Herbrand models to orbits of Herbrand interpretations. Orbits capture both the declarative, model-theoretic meaning of programs as well as their inferential behavior. Logically and intentionally different programs can produce orbits that simulate each other. Simple examples of such behavior are compellingly exhibited with space-time diagrams of the programs as cellular automata. Construing a program as a cellular automaton leads to a general method for simulating any covered program with a Horn …


Comment On 'Simulation Of A Two-Dimensional Rayleigh-Bénard System Using The Direct Simulation Monte Carlo Method, Alejandro Garcia, F. Baras, M. Malek Mansour Jan 1995

Comment On 'Simulation Of A Two-Dimensional Rayleigh-Bénard System Using The Direct Simulation Monte Carlo Method, Alejandro Garcia, F. Baras, M. Malek Mansour

Faculty Publications

No abstract provided.


Effects Of Technology Mapping On Fault Detection Coverage In Reprogrammable Fpgas, Kevin A. Kwiat, Warren Debany, Salim Hariri Jan 1995

Effects Of Technology Mapping On Fault Detection Coverage In Reprogrammable Fpgas, Kevin A. Kwiat, Warren Debany, Salim Hariri

Electrical Engineering and Computer Science - All Scholarship

Although Field-Programmable Gate Arrays (FPGAs) are tested by their manufacturers prior to shipment, they are still susceptible to failures in the field. In this paper, test vectors generated for the emulated (i.e., mission) circuit are fault simulated on two different models: the original view of the circuit, and the design as it is mapped to the FPGA's logic cells. Faults in the cells and in the programming logic are considered. Experiments show that this commonly-used approach fails to detect most of the faults in the FPGA.


A Monte Carlo Simulation Of Coulomb Collisions And Wave-Particle Interactions In Space Plasma At High Latitudes, Imad Ahmad Barghouthi May 1994

A Monte Carlo Simulation Of Coulomb Collisions And Wave-Particle Interactions In Space Plasma At High Latitudes, Imad Ahmad Barghouthi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Four studies were considered to simulate the ion behavior in the auroral region and the polar wind.

In study I, a Monte Carlo simulation was used to investigate the behavior of O+ ions that are E x B-drifting through a background of neutral O, with the effect of O+(Coulomb) self-collisions included. Wide ranges of the ion-to-neutral density ratio ni / nn and electrostatic field E were considered in order to investigate the change of ion behavior with respect to the solar cycle and altitude. For low altitudes and/or solar minimum (ni / …


Direct Simulation Monte Carlo For Thin Film Bearings, Alejandro Garcia, B. Alder, F. J. Alexander Jan 1994

Direct Simulation Monte Carlo For Thin Film Bearings, Alejandro Garcia, B. Alder, F. J. Alexander

Faculty Publications

The direct simulation Monte Carlo (DSMC) scheme is used to study the gas flow under a read/write head positioned nanometers above a moving disk drive platter (the slider bearing problem). In most cases, impressive agreement is found between the particle-based simulation and numerical solutions of the continuum hydrodynamic Reynolds equation which has been corrected for slip. However, at very high platter speeds the gas is far from equilibrium, and the load capacity for the slider bearing cannot be accurately computed from the hydrodynamic pressure.


Functional Representation And Reasoning About The F/A-18 Aircraft Fuel System, M. Pegah, J. Sticklen, William E. Bond Jan 1993

Functional Representation And Reasoning About The F/A-18 Aircraft Fuel System, M. Pegah, J. Sticklen, William E. Bond

Computer Science Faculty Research & Creative Works

Functional reasoning, a subfield of model-based reasoning, is discussed. This approach uses abstractions of a device's purpose to index behaviors that achieve that purpose. Functional modeling, a variation on this method, also uses simulation as a core reasoning strategy. The complex causal knowledge of a device along functional lines is decomposed, then a causal story of how the device will operate in a particular situation given stated boundary conditions is composed. The application of the functional approach to modeling the fuel system of a F/A-18 aircraft is described. The representation of the F/A-18 fuel system includes 89 component devices, 92 …


Hydrodynamic Stability Of The Breakwater Extension At Rrviksand, Norway, Alfonse Dubi Jun 1992

Hydrodynamic Stability Of The Breakwater Extension At Rrviksand, Norway, Alfonse Dubi

Tanzania Journal of Engineering and Technology (TJET)

The fishing port of Årviksand in Norway, which is situated on an open coast, is artificially harboured by breakwaters. The northern and southern breakwaters which were built in 1930—ies and 1950—ies respecti vely have been on several occasions damaged by heavy storms. This resul ted in the need for further protection by extending the northern breakwater. This paper describes one of the hydrodynamic tests on the breakwater extension. The breakwater, with a berm breakwater concept design, is subjected to the joint probability of sea level elevation and wave heights (in other 'fatigue" test). words , It is found that cover …


A Mathematical Model And Simulation Of Natural Circulation Loop Thermalhydraulics, Nihad E. Daidzic Mar 1992

A Mathematical Model And Simulation Of Natural Circulation Loop Thermalhydraulics, Nihad E. Daidzic

Aviation Department Publications

In this work, a simple, nonlinear, seventh-order mathematical model with lumped parameter analysis of the thermalhydraulic processes in a natural circulation steam boiler loop is presented. Digital simulation has been performed in order to predict open loop transients in severe accidental situations. Parts of the circulation loop such as the steam drum, downcomer, and riser were modelled separately on the basis of the integral balance equations. The two-phase flow in the steam drum and in the riser was modelled with the aid of a homogeneous-equilibrium, two-phase flow model. Special care was taken to ensure the stability of the numerical scheme, …


Real-Tv : Rtp/L3'S Visual Monitor, Richard Czop Jan 1992

Real-Tv : Rtp/L3'S Visual Monitor, Richard Czop

Theses

Today many real-world activities are being monitored and controlled by some type of micro-processor based system. Emphasis is placed on manufacturing and controlling through the use of computers. The inherent nature of these real-world applications makes them difficult to control and monitor. They must be built meeting strict timing constraints and must be predictable. We need to develop simplistic, reliable, and cost effective methods for building, evaluating, monitoring and controlling these complex systems. These tools should provide the user with system insight. At the New Jersey Institute of Technology Real-Time Computing Laboratory, we are building a system that will provide …


Numerical Simulation Of Saturated Flow With Fractal Analysis Of The Hydraulic Conductivity Distribution, Joan Leilani Oana May 1991

Numerical Simulation Of Saturated Flow With Fractal Analysis Of The Hydraulic Conductivity Distribution, Joan Leilani Oana

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The purpose of this report is to investigate the behavior of a nonreactive contaminant in a perfectly stratified aquifer under uniform, steady-state flow. The design and the implementation of a solute transport model which characterizes the heterogeneities of the aquifer properties in a stochastic framework is reviewed. The model closely examines the advection and dispersion of the plume. The advection is the process by which the plume is transported in the aquifer by the bulk average motion of the groundwater whereas the dispersion refers to the spreading of the plume about its mean displacement position. The relationship between the fractally …


Regionalization Of Flood Data Using Probability Distributions And Their Parameters, Nageshwar Rao Bhaskar, Carol Alf O'Connor, Harold Andrew Myers, William Paul Puckett Dec 1989

Regionalization Of Flood Data Using Probability Distributions And Their Parameters, Nageshwar Rao Bhaskar, Carol Alf O'Connor, Harold Andrew Myers, William Paul Puckett

KWRRI Research Reports

The U. S. Geological survey recently used the method of residuals to delineate seven flood regions for the State of Kentucky. As an alternative approach, the FASTCLUS clustering procedure of the Statistical Analysis system (SAS) is used in this study to delineate five to six cluster regions in conjunction with statistical properties of the AMF series, like the coefficient of variation as estimated using method of L-moments, LCV, the parameters of the EVl and GEV flood frequency distributions, and the specific mean annual flood, QSP. For both cluster and USGS flood regions, regionalized flood frequency growth curves are developed and …


Mtclim: A Mountain Microclimate Simulation Model, United States Department Of Agriculture, Forest Service Jan 1989

Mtclim: A Mountain Microclimate Simulation Model, United States Department Of Agriculture, Forest Service

Forestry

A model for calculating daily microclimate conditions in mountainous terrain is presented. Daily air temperature, shortwave radiation, relative humidity, and precipitation are extrapolated from data measured at National Weather Service stations. The model equations are given and the paper describes how to execute the model. Model outputs are compared with observed date from several mountain sites.


Demonstrations Of Arkansas' Water Management Simulator, Leslie E. Mack Sep 1985

Demonstrations Of Arkansas' Water Management Simulator, Leslie E. Mack

Arkansas Water Resources Center Technical Reports

One of the larger stumbling blocks to comprehensive water management is the lack of public understanding of the multitude of variables that operate at the same time within the hydrologic cycle. With more public understanding, there is greater public support for various water projects. Dr. John R. Amend from Montana State University developed a water management simulator which could handle a large number of variables simultaneously of natural surface and groundwater flow plus a number of water use variables on an accelerated time sequence. By using several remote control devices, participants can "control" their water use but have no control …


Collecting Data About Logic Simulation, Roger D. Chamberlain, Mark A. Franklin May 1985

Collecting Data About Logic Simulation, Roger D. Chamberlain, Mark A. Franklin

All Computer Science and Engineering Research

Design of high performance hardware and software based gate-switch level logic simulators requires knowledge about the logic simulation process itself. Unfortunately, little data is publically available concerning key aspects of this process. An example of this is the lack of published empirical measurements relating to the time distribution of events generated by such simulators. This paper presents a gate-switch level logic simulator lsim which is oriented towards the collection of data about the simulation process. The basic components of lsim are reviewed, and its relevant data gathering facilities are discussed. An example is presented which illustrates the use of lsim …


Monte Carlo Simulation Of The Game Of Twenty-One, Douglas E. Loer Jan 1985

Monte Carlo Simulation Of The Game Of Twenty-One, Douglas E. Loer

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The purpose of this paper is to demonstrate the application of computer simulation to the game of Twenty-One to predict a player's expected return from the game. Twenty-One has traditionally been one of the most popular casino games and has attracted much effort to accurately estimate the house's true advantage. Probability theory has been tried, but the thousands of different combinations of cards possible in all hands throughout the entire pack make it practically impossible to apply probability theory without overlooking some possibilities. For this reason, Twenty-One is a perfect candidate for simulation. By blocking several simulations, normal theory can …


Water Management Simulator Presentations, Leslie E. Mack Sep 1984

Water Management Simulator Presentations, Leslie E. Mack

Arkansas Water Resources Center Technical Reports

One of the larger stumbling blocks to comprehensive water management is the lack of public understanding of the multitude of variables that operate at the same time within the hydrologic cycle. With more public understanding, there is greater public support for various water projects. Dr. John R. Amend from Montana State University developed a water management simulator which could handle a large number of variables simultaneously of natural surface and groundwater flow plus a number of water use variables on an accelerated time sequence. By using several remote control devices, participants can "control" their water use but have no control …


A Microsystem Sediment-Water Simulation Study For The Proposed Jordanelle Reservoir, Heber City, Utah, United States Department Of The Interior, Bureau Of Reclamation Dec 1983

A Microsystem Sediment-Water Simulation Study For The Proposed Jordanelle Reservoir, Heber City, Utah, United States Department Of The Interior, Bureau Of Reclamation

Water

The technique of microsystem sediment-water simulation was used to predict water quality data for the proposed Jordanelle Reservoir, Heber City, Utah. Simulation microsystems were prepared for four sites located in the north arm of the reservoir basin including two sites located in an abandoned acid mine tailings pond. Data obtained from the tailings pond microsystems indicated that low pH water and high trace metal concentrations will exist in the north arm of the reservoir. These data suggested that some kind of membrane or compacted earth lining will be necessary to seal and contain the mine spoilage. Other sites in the …


The San Luis Valley Groundwater Dispute, David Harrison, Jeris Danielson Jun 1983

The San Luis Valley Groundwater Dispute, David Harrison, Jeris Danielson

Groundwater: Allocation, Development and Pollution (Summer Conference, June 6-9)

25 pages (includes illustrations and map).


Agenda: Groundwater: Allocation, Development And Pollution, University Of Colorado Boulder. Natural Resources Law Center Jun 1983

Agenda: Groundwater: Allocation, Development And Pollution, University Of Colorado Boulder. Natural Resources Law Center

Groundwater: Allocation, Development and Pollution (Summer Conference, June 6-9)

Even before the [Natural Resources Law] Center was established [in the fall of 1981], the [University of Colorado] School of Law was organizing annual natural resources law summer short courses. To date four programs have been presented:

- July 1980: "Federal Lands, Laws and Policies-and the Development of Natural Resources"

- June 1981: "Water Resources Allocation: Laws and Emerging Issues"

- June 1982: "New Sources of Water for Energy Development and Growth: lnterbasin Transfers"

- June 1983: "Groundwater: Allocation; Development and Pollution"

(Reprinted from Resource Law Notes, no. 1, Jan. 1984, at 1.)

University of Colorado School of Law professors …


Simulation Of Burley Tobacco Harvesting-Housing Systems, Ronald L. Bingner, Larry G. Wells, Thomas C. Bridges, George A. Duncan Jan 1982

Simulation Of Burley Tobacco Harvesting-Housing Systems, Ronald L. Bingner, Larry G. Wells, Thomas C. Bridges, George A. Duncan

Biosystems and Agricultural Engineering Faculty Publications

A computer model has been developed using systems analysis techniques to simulate the labor and equipment aspects of harvesting burley tobacco. By varying the parameters of the model the user can determine a harvesting and housing strategy based on labor and equipment availability.


Numerical Model Simulation Of Offshore Flow During The Winter Season, Maria Cintia Piccolo Jan 1981

Numerical Model Simulation Of Offshore Flow During The Winter Season, Maria Cintia Piccolo

OES Theses and Dissertations

Because of the step function variability of heat and moisture flux in coastal zones, adequate descriptive models of mesoscale coastal circulation and weather patterns demand high spatial resolution in the analysis of wind, temperature and moisture patterns. To obtain realistic concepts of offshore flow the sparse offshore data networks need to be supplemented by mesoscale numerical models. The problems associated with the modeling of offshore flow across the east coast of the United States during the winter season have been investigated with a simple two dimensional numerical model of the planetary boundary layer.

The model has two predictive equations for …


Effects Of Changes In Surface Water Regime And/Or Land Use On The Vertical Distribution Of Water Available For Wetland Vegetation: Dynamic Model Of The Zone Of Aeration (Part 1 Of Completion Report For Project A-023-Ark), Robert N. Maccallum, R. A. Sims Jun 1980

Effects Of Changes In Surface Water Regime And/Or Land Use On The Vertical Distribution Of Water Available For Wetland Vegetation: Dynamic Model Of The Zone Of Aeration (Part 1 Of Completion Report For Project A-023-Ark), Robert N. Maccallum, R. A. Sims

Arkansas Water Resources Center Technical Reports

A mathematical model by Green, simulating one-dimensional vertical ground-water movement in unsaturated soils of the prairie region of Kansas, has been adapted for use in a wetlands environment typified by the wetlands forest of Eastern Arkansas. The model consists of two second-order, non-linear, partial differential equations and an algorithm for their numerical solution. The original model was extended to include functions for seasonal changes in transpiration and for drainage of excess precipitation. Before the addition of the two functions, the model reliability was limited to one growth season.


Evaluation Of Detention Basins For Controlling Urban Runoff And Sedimentation, C. T. Haan, A. D. Ward Aug 1978

Evaluation Of Detention Basins For Controlling Urban Runoff And Sedimentation, C. T. Haan, A. D. Ward

KWRRI Research Reports

This report summarizes the work completed under the research project "Evaluation of Dentention Basins for Controlling Urban Runoff and Sedimentation." The main project accomplishments were:

(1) a demonstration of the desirability of considering systems of urban stormwater detention basins as opposed to individual basin design,

(2) the development of a systems analysis approach for least cost selection of a system of dentention basins for meeting a preset hydrologic objective,

(3) the development of a mathematical, computer-based simulation model of the performance of sediment retention basins,

(4) partial verification of the sediment basin model and

(5) the development of design recommendations …


Development And Preliminary Application Of Mathematical Models To The Weber Basin, W. J. Grenney, D. S. Bowles, M. D. Chambers, J. P. Riley Dec 1974

Development And Preliminary Application Of Mathematical Models To The Weber Basin, W. J. Grenney, D. S. Bowles, M. D. Chambers, J. P. Riley

Reports

The adoption of stream standards, whether for direct application or for the establishment of realistic effluent standards, creates a need to predict the impact of pollution loads on river water quality during critical flow periods or as the result of future user demands. Because of the complexity of aquatic systems, mathematical models are an excellent medium for bringing together the state-of-the-art knowledge from a variety of disciplines into a form which can be readily applied to practical problems. Applying a mathematical model to a river system has the added advantage of providing a structure for the systematic consideration of the …


Mathematical Simulation Of Temperatures In Deep Impoundments: Verification Tests Of The Water Resources Engineers, Inc. Model - Horsetooth And Flaming Gorge Reservoirs, Engineering And Research Center, Bureau Of Reclamation Nov 1973

Mathematical Simulation Of Temperatures In Deep Impoundments: Verification Tests Of The Water Resources Engineers, Inc. Model - Horsetooth And Flaming Gorge Reservoirs, Engineering And Research Center, Bureau Of Reclamation

All U.S. Government Documents (Utah Regional Depository)

Successful use of predictive mathematical models requires verification of the accuracy of the models by applying them to existing situations where the prediction can be compared with reality. A Corps of Engineers' modification of a deep reservoir thermal stratification model developed by Water Resources Engineers, Inc., was applied to two existing Bureau of Reclamation reservoirs for verification. Diffusion coefficients used for the Corps' Detroit Reservoir were found to apply to Horsetooth Reservoir in Colorado, for which very good computer input data were available. The Detroit diffusion coefficients gave a reasonable simulation of Flaming Gorge Reservoir in Wyoming and Utah, which …