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Simulation

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Articles 391 - 403 of 403

Full-Text Articles in Engineering

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, …

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Use Of Time Varying Dynamics In Neural Network To Solve Multi-Target Classification, S. N. Balakrishnan, J. Rainwater Jan 1992

Use Of Time Varying Dynamics In Neural Network To Solve Multi-Target Classification, S. N. Balakrishnan, J. Rainwater

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Several types of solutions exist for multiple target tracking. These techniques are computation-intensive and in some cases very difficult to operate online. The authors report on a backpropagation neural network which has been successfully used to identify multiple moving targets using kinematic data (time, range, range-rate and azimuth angle) from sensors to train the network. Preliminary results from simulated scenarios show that neural networks are capable of learning target identification for three targets during the time period used during training and a time period shortly after. This effective classification period can be extended by the use of networks in coordination …

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Pluman, Decision Support System For Groundwater Contaminant Plume Simulation/Optimization Management Model, Herminio H. Suguino, Richard C. Peralta Jan 1992

Pluman, Decision Support System For Groundwater Contaminant Plume Simulation/Optimization Management Model, Herminio H. Suguino, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

No abstract provided.

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Decoupled Dynamics For Control And Estimation, S. N. Balakrishnan Jan 1991

Decoupled Dynamics For Control And Estimation, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Decoupling of the dynamical equations in polar coordinates is used to develop a control scheme for use in target-intercept problems with passive measurements. By defining a pseudo control variable in the radial coordinate, the radial dynamics is made independent of the transverse dynamics. After solving for the radial control, the transverse control is determined through solutions to a two-point boundary value problem. Numerical results from a six degree-of-freedom simulation which used the decoupled control indicate that it is better than the completely Cartesian coordinate control for most of the cases considered. Decoupled control, though, is obtained iteratively through a two-point …

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A Stratified Air Model For Simulation Of Attic Thermal Performance, Florida Solar Energy Center, Danny Parker Jan 1991

A Stratified Air Model For Simulation Of Attic Thermal Performance, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

An improved computer simulation model for attics has been developed. The model accounts for detailed radiation, buoyancy and wind driven air flows and thermal stratification within the attic airspace. Through comparison with measured data, the paper examines the relative importance of the various modeling parameters and assumptions upon simulation accuracy. Stratification of the attic air was found to be a critical modeling characteristic which is typically ignored in building energy simulations. Both model and measurement results shows that air stratification increases significantly when low-emittance surfaces are included.

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Use Of Simplex Algorithm For Optimizing Simulation Models, M. Ehteshami, L. S. Willardson, Richard C. Peralta Jun 1990

Use Of Simplex Algorithm For Optimizing Simulation Models, M. Ehteshami, L. S. Willardson, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

A methodology and computer model is developed to determine economically optimum closed subsurface drainage systems in irrigated areas. The mode 1 maximizes net benefits, by comparing profit driven by crop yields to drain system cost and selects an optimum drain layout. The optimization methodology used is the SIMPLEX method (Nelder and Mead, 1965). The SIMPLEX model was linked to the subsurface drainage model DRAINMOD (Skaggs, 1982) and to the surface hydraulic model KINE (Walker and Skogerboe 1987). The selected optimum drainage system maximizes the difference between total revenue, and the total cost of installation, operation and management of a particular …

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Simulation Of The Effect Of Wind On Rectangular Sedimentation Tanks, Muttucumaru Sivakumar, S A. Lowe Jan 1990

Simulation Of The Effect Of Wind On Rectangular Sedimentation Tanks, Muttucumaru Sivakumar, S A. Lowe

Faculty of Engineering - Papers (Archive)

A numerical model is presented to simulate the effect of wind action on rectangular sedimentation tanks used in water and wastewater treatment plants. The mathematical model uses the k-r. model for fl uid flow and sediment transport, and is solved using an explicit finite diffence scheme incorporating a penalty function approach. Simulations of fluid flow velocity and aeqiment concentration are presented for two wind speeds in two directions. It is shown that the effect of wind action is significant and future design of sedimentation tanks should include this parameter.

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Evaluating Water Policy Options By Simulation, Ann W. Peralta, Richard C. Peralta, Keyvan Asghari Jun 1985

Evaluating Water Policy Options By Simulation, Ann W. Peralta, Richard C. Peralta, Keyvan Asghari

Civil and Environmental Engineering Faculty Publications

Computer simulation models are used to predict the effects of three sample water policy decisions on selected conjunctive water use/sustained groundwater yield strategies for the Arkansas Grand Prairie. The three applications illustrate the facility of the target objective approach in providing an interface for legal, economic and engineering analysis. The approach is used to evaluate potential water management decisions at the judicial, legislative and water management district levels

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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 …

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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.

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Heat Pump Research Programme At University College Dublin (1976), Seamus Timoney, Jim Mcgovern Jan 1976

Heat Pump Research Programme At University College Dublin (1976), Seamus Timoney, Jim Mcgovern

Conference Papers

This paper describes heat pump research at University College Dublin in 1976 relating to an air-to-air heat pump. The plant under test and its instrumentation are described and some measured performance data are presented. A heat pump simulation program is described. A theoretical comparison of refrigerants 12, 22 and 502 is presented with graphs of performance parameters as a function of operating conditions.

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Development Of Helicopter Flight Path Models, Alfred Fermelia, Donald A. Gyorog, V. J. Flanigan Jan 1976

Development Of Helicopter Flight Path Models, Alfred Fermelia, Donald A. Gyorog, V. J. Flanigan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The objective of this paper is to present general techniques for simulating helicopter flight trajectory response. During flight the pilot manipulates the controls either to trim the helicopter for steady flight by balancing the external forces and moments or to produce a desired maneuver by controlling the unbalance of these forces and moments. Discussions of the physical phenomena involved with the aerodynamics of the rotors and fuselage are given in [1] through [3]. The simulated control function will be composed forward-aft cyclic, lateral cyclic, pedal, and collective. This control will be represented by the vector

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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 …

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