Modelling Definition and 250 Threads

I'm kinda of messing around with a model of a biological system, I've found the equilibriums and decided I'd get the stability relations as well. I tried using mathematica to get the eigenvalues of the system to see if its stable or not and when I got the eigenvalues of my matrix mathematica...

Hello, nice to find this kind of great forum. I am quite puzzled with the task that was given to me: How to model mechatronical system (multidomain) on early product development stage? So, because product is not well defined yet, there are much uncertainties what to model(!) So, how to...

Modelling Density as a Function of Many Objects Hello, My question is somewhat difficult to express but this is the best way I can come up with. Lets say I have a mass of material which has a charge throughout its entirety. This material has a very special property where the density of the...

Hi I am trying to model the Brayton cycle in a gas turbine that is used for electricity generation. My main aim is to be able to fully power the x amount of daily electricity load of a building using this machine. In order to do this, is it correct to do a backwards model and find what...

Homework Statement Model a 1KW windturbine. Homework Equations in this link u will find the equation (its equation 2-3) for a fit for a cp(lambda,beta) curve. It has 6 coefficients. The coefficients given are particular to a 1.5 MW windturbine. Does anyone know where I can find any...

Hi I will like some advice. I intend to know more about mathematical modelling. Can anyone recommend any useful books, websites of software? How does one develop an interest in it? I will like to specialise in the modelling of energy systems and not sure how to do it. Please advise

I am not a physicist, so please excuse the gaps in my knowledge. I am writing a would-be philosophical essay about models in different fields of research. In most general terms, my task is to consider how modelling can be useful in the pursuit of knowledge in the widest understanding of the...

i want to learn how to use experimental data to produce effective mathematical model for good prediction of any phenomenon. my mathematical background is : i know about single and multivariable calculus,college algebra,introductory probability theory,trigonometry,vector algebra and calculus,and...

I am interested in looking at the voltage component of a short (possibly nanosecond width) pulse in a coaxial cable along the cable at a given distance, Z, along the line. I am "cheating" by using the steady state Telegrapher's equation [Eq. 1] and formulating a periodic pulse approximation. It...

We have a model where we are to predict the temperature of the water outlet stream of a storage tank. Basically we have a solar heating collector that heats up a fluid which is present in a storage tank. The flow process is that the fluid flows through the pipes to the solar collector and back...

[PLAIN]http://img198.imageshack.us/img198/6579/mechanics2.jpg I've done the first bit (showing x and \dot{x} are always perpendicular) but how do I show that the motion lies in a plane? Also, how do I do the final part?

Hi all, I am a student designing a camera fixture for my senior design project. We are halfway through our project right now and we are trying to do some validation stuff for our fixture. One of the requirements for our fixture is for it to withstand 6 g's of shock during...

Hello ! I'm a beginner in Abaqus and for that I've tried to follow this tutorial http://fliiby.com/file/831535/i3rkmyhurs.html . I was all ok until I tried to make the mesh (chapter 3.7.2 in tutorial). It said that they are parts of the assemby that are too complex to be meshed with those...

I am trying to model the following situation: Let say i have an obstacle with known mass, and I know the coefficient of static and dynamic friction between the obstacle material and the floor. A car traveling at a fixed velocity is to impact the obstacle. For simplicity i will first consider...

Hi, I am in need of some expert advice please. I am enrolling for my honours degree in mathematics next year. I am trying to mix it up in order to have a strong foundation in pure mathematics with specialisation in applied mathematics. My interests are financial mathematics, probability...

Hi all. I'd like to create a basic model of the forces acting on a sail (wind sail, like a tail ship) A couple of things I was thinking about: 1) can create a very simple model where wind is 'one' force acting on the a uniform body. 2) model wind as vectors. This is where I am a little...

in a scientific study, the size , p of a population at t hours is being studied. Initially p = 560 and after 6 hours, p is found to be 1218. In a simple model of population growth, the rate of the population is taken to be proportional to the population at that time. Using this model predict...

Greetings Engineers I am relatively new to pro/e modelling. Most of the solids I have created till date using pro/e have been simple ones using mostly the extrude or revolve tool. I am presented with a problem as I try to create a more complex model of a crane arm ( similar to the arm in -...

Homework Statement A car depreciates over time. x(years) y ($) 1 14000 2 9100 3 6200 4 4000 5 3000 i) determine the linear model (1 mark) ii) determine the quadratic model (1 mark) iii) determine the...

Homework Statement A college graduate borrows $100,000 at an interest rate of 9% to buy a house. The college graduate plans to make payments at a monthly rate of 800(1+t/120), t is the number of months since the loan was made. Assuming this payment schedule can be maintained, when will the loan...

small signal diode modelling i understand what it is but when i get asked a question like: if vin(t)=2.5+cos(2*pi*100*t) for 0<t<30 use the small signal model of the diode to predict the output voltage of the circuit i have added. assume the opamp is ideal R=2000 Is=10e-16 so i know...

I have an assigned project in Physics with numerical modeling, to which I am supposed to use Euler's method to approximate the velocity of a "mass sliding down a frictionless in the shape of a quarter circle of radius 2.00 m." The assignment also states: "Do three trials: t = 0.2s, t = 0.02s...

Hi everyone, Homework Statement I've been having a bit of trouble with my mathematics coursework. We have to model an aeroplane that has just landed with two equations. One prior to braking, one after. I've used a model with a quadratic drag approximation; and I'm not certain if my result...

Hi, I am looking to get some good information sources on modelling nuclear power in power plants and related fields. Anyone got any good starting points ? P.S. I am a biomedical engineer looking into different fields.

Hi, my name is Steve.. I am working on a ducted fan. I want to simulate it in Fluent in order to optimize my design. I know that sliding mesh technique and multiple reference frame method will be used but I am having problems in Gambit. I do not know how to model it in Gambit. I have made...

Given a power spectral density Sn(f) (or alternatively the autocorrelation function), is there a way to output random noise in Mathematica? Not sure if anyone here will know this but it's worth a try.

Hi all, I am currently working on a water pipeline project and am investigating a pipe burst scenario at a pump station with the aim of producing a flow rate entering the pump room in the event of a burst. For simplification and what has been used previously on similar jobs is to model...

Hi, I am just finished my Calc II class and a programming class and I am trying to write a computer graphics shader... My goal is to model this scenario: "Imagine a brick wall standing on a plane --- a shadow will be cast depending on the light source" ---my goal is to model the dispersion of...

How is it best to model Helium gas, Ideal gas equation? Dieterici? Van der Waals? some other equation? Also if it is dieterici or van der waals,what the values of a and b, the constants in the equation of state.

hi, when modelling the shape of a hydrogen atom orbital, is it the real part of the spherical harmonics that i plot? thanks

i need help in modeling magnetic field which will be created using arrangement of magnets which may be in motion ,, i want a simulation model or some software for this please suggest some... thanks

Hi guys, Im a newbie to this site... I have been wrking on a simulink model of a F1 car for a few days.I wanted to simulate the start of a F1 car from standstill.. I used the following basic concepts: 1) The engine is revved at say around 11000 .rpm 2)So when the lights go off, I engage the...

Let us assume a dynamic system which has vector with 'n' components (which are non-negative integers from 1->n) at time t=1. In other words we have a permutation over 1->n at time t=1. Assuming time to be discrete, at any time time 't' , the system evolves such that there are 't' permutations...

Hi, I am looking for some guidance w.r.t modelling real world phenomena using ODE/PDE/SDE type equations. Are there books which go into the issues of modelling real world phenomena with these sorts of equations? Thanks in advance, Excor.

Hi, I am trying to calculate the power of a reflected electromagnetic field and can't find a physical explanation for a given solution. I've noticed the following example: The Plane has a radar for altitude measurement which emmits the power Ptx at the frequency ftx. Calculate the power...

If we were to model the universe can we calculate the gravitational information rate which a particle receives in a universe?

when modelling a function for a Fourier series, what determines which function i select from the forcing function for an and bn? eg in the following would 1-t^2 be used in the an or bn formula? http://users.on.net/~rohanlal/fourier2.jpg

Hello all. I'm modelling several new aircraft as mods for a flight sim. These mods are all WW2 birds like the Kittyhawk and Ta152. The generic computer models have a series of terms I am unsure about. So far I've been using existing aircraft modelling as a guideline but as we are expanding...

Homework Statement Hi all, I'll outline the situation first, then I'll ask about what I need. Tank (designed by me / other students) which has no closed in top or bottom. Can be any shape, i.e. cylinder / cone / square etc etc. Made from cardboard with plastic bag in the middle acting...

Hi, I am trying to simulate condensation of water in air. I am using the shan-chen multi-phase multi-component model in order to achieve this (a variation of the Lattice Boltzmann Equation, not too important). The goal ultimately is to study the effect of condensation in fuel cell membranes...

Hi PF,I'm working on a semi-classical model for a group of rather strange polymers based on carbon, nitrogen, and oxygen. In this treatment, I'm approximating the bond length and bond angle to be more or less classical (ie. ball and stick). But I would also like to treat the dihedral angles...

Hello All. I am a second year engineering student switching over from Mechatronics engineering to physics with a minor in computer sciences. While I have done some programming in C, C++, Java, TCL and Assembler, I would like to know how I would approach modeling physical phenomena...e.g basic...

Homework Statement "The very simple population model for a resource limited population with constant immigration, and no breeding, M'(t) = M(S-M) + I attempts to describe the growth of corals on a reef. Function M(t) represents the biomass of corals." a - Explain which term gives the...

Homework Statement I have 3 pairs of resistors and capacitors, with each pair in parallel. These pairs are in series with another resistor and a voltage source. I have been asked to find the voltage across the resistor in the middle pair as a function of time, assuming that at time t=0 the...

Hello! I chose an aspect of a dynamical system exhibiting resonance to model. The focus of the project is on the resonant response of the system. If the wind has a frequency that matches the natural frequency of a turbine, then the turbine will resonate due to wind. I am working on modelling...

This post simply represents a learning process, my own. As such, it is only attempting to understand how the energy density might have changed with time and what can be inferred from this. There are 3 diagrams attached to this post, figure-1 is an attempt to show the relative density of matter...

Modelling "Gravitational" Motion Hi All, I am new here and this is not a homework question... I'm turning 40 this year and my retention of physics is low to say the least. I am trying to rekindle some knowledge... Just for fun! I am trying to use a spreadsheet to model the motion of a...

so I am tearing my hair out with this one... the density of the Earth's atmostsphere vaires with height r above the Earth's surface as p = p(o) exp(-r/r(o)) where p(o) the density of the air at ground level, is 1.3 kg/m^3 and r(o) the scale height is 8km use this to estimate an...

Okay, I'm doing my yr 11 Mathematics assignemnt and I need help. How do you find a Logistic or Polynomial function/equation using data? (in steps please!) I could just give some example data as... an example, but I think I'll just throw 1 small section of my assignment, use the data or...

I don't understand how muscles create torque. More specifically, I am trying to model muscles inside a computer program. I have two line segments (bones) from A->B and B->C, so B is obviously the joint. I was thinking of modeling a muscle as a spring going from A to somewhere on the line BC (but...