Monte Carlo Simulations of Some Dynamical Aspects of Drop Formation

In this work we present some results from computer simulations of dynamical aspects of drop formation in a leaky faucet. Our results, which agree very well with the experiments, suggest that only a few elements, at the microscopic level, would be necessary to describe the most important features of the system. We were able to set all parameters of the model in terms of real ones. This is an additional advantage with respect to previous theoretical works.Comment: 7 pages (Latex), 6 figures (PS) Accepted to publication in Int. J. Mod. Phys. C Source Codes at http://www.if.uff.br/~arlim

Including Risk in Economic Feasibility Analyses: The Case of Ethanol Production in Texas

The widespread use of personal computers and spreadsheet models for feasibility studies makes risk-based Monte Carlo simulation analysis of proposed investments a relatively simple task. Add-in simulation packages for Microsoft® Excel can be used to make spreadsheet models stochastic. Rather than basing investment decisions on point estimates, investors can easily estimate the implied distributions of returns for uncertain investments and calculate the risk of an investment as well as the probability of success. The benefits of using Monte Carlo simulation to analyze a risky investment are demonstrated using an ethanol plant as an example.economic feasibility analysis, ethanol feasibility, risk management, stochastic simulation, Agribusiness, Research and Development/Tech Change/Emerging Technologies,

Probabilistic structural mechanics research for parallel processing computers

Aerospace structures and spacecraft are a complex assemblage of structural components that are subjected to a variety of complex, cyclic, and transient loading conditions. Significant modeling uncertainties are present in these structures, in addition to the inherent randomness of material properties and loads. To properly account for these uncertainties in evaluating and assessing the reliability of these components and structures, probabilistic structural mechanics (PSM) procedures must be used. Much research has focused on basic theory development and the development of approximate analytic solution methods in random vibrations and structural reliability. Practical application of PSM methods was hampered by their computationally intense nature. Solution of PSM problems requires repeated analyses of structures that are often large, and exhibit nonlinear and/or dynamic response behavior. These methods are all inherently parallel and ideally suited to implementation on parallel processing computers. New hardware architectures and innovative control software and solution methodologies are needed to make solution of large scale PSM problems practical

A conceptual framework for using Doppler radar acquired atmospheric data for flight simulation

A concept is presented which can permit turbulence simulation in the vicinity of microbursts. The method involves a large data base, but should be fast enough for use with flight simulators. The model permits any pilot to simulate any flight maneuver in any aircraft. The model simulates a wind field with three-component mean winds and three-component turbulent gusts, and gust variation over the body of an aircraft so that all aerodynamic loads and moments can be calculated. The time and space variation of mean winds and turbulent intensities associated with a particular atmospheric phenomenon such as a microburst is used in the model. In fact, Doppler radar data such as provided by JAWS is uniquely suited for use with the proposed model. The concept is completely general and is not restricted to microburst studies. Reentry and flight in terrestrial or planetary atmospheres could be realistically simulated if supporting data of sufficient resolution were available

Why Excel?

This article is not the usual Excel pedagogy fare in that it does not provide an application or example taught via a spreadsheet. Instead, it briefly reviews the history of spreadsheets in the economics classroom and explores the current environment, with an emphasis on modern learning theory. The conclusion is not surprising: spreadsheets improve learning outcomes across the economics curriculum and are increasingly being used. They offer the “just right” option that gives a middle way between too little and too much focus on software in an economics course

Application of control theory to dynamic systems simulation

The application of control theory is applied to dynamic systems simulation. Theory and methodology applicable to controlled ecological life support systems are considered. Spatial effects on system stability, design of control systems with uncertain parameters, and an interactive computing language (PARASOL-II) designed for dynamic system simulation, report quality graphics, data acquisition, and simple real time control are discussed

A bibliography on parallel and vector numerical algorithms

This is a bibliography of numerical methods. It also includes a number of other references on machine architecture, programming language, and other topics of interest to scientific computing. Certain conference proceedings and anthologies which have been published in book form are listed also

The SIMRAND 1 computer program: Simulation of research and development projects

The SIMRAND I Computer Program (Version 5.0 x 0.3) written in Microsoft FORTRAN for the IBM PC microcomputer and its compatibles is described. The SIMRAND I Computer Program comprises eleven modules-a main routine and ten subroutines. Two additional files are used at compile time; one inserts the system or task equations into the source code, while the other inserts the dimension statements and common blocks. The SIMRAND I Computer Program can be run on most microcomputers or mainframe computers with only minor modifications to the computer code

Household Production and the Excess Sensitivity of Consumption to Current Income

Empirical research on the permanent income hypothesis (PIH) has found that consumption growth is excessively sensitive to predictable changes in income. This finding is interpreted as strong evidence against the PIH. We propose an explanation for apparent excess sensitivity that is based on a quantitative equilibrium version of Becker's (1965) model of household production in which permanent income consumers respond to shifts in sectoral wages and prices by substituting work effort and consumption across home and market sectors. Although the PIH is true, this mechanism generates apparent excess sensitivity because market consumption responds to predictable income growth.