Modeling Definition and 609 Threads

Hi, I am a beginner with the use of relap. So this might be a bit silly. I am studying the heat transfer between a fuel rod and a single channel of coolant. One of the inputs for the heat structure is the direct moderator heating multiplier. What is that and how do I find its value? Thanks...

I am starting a project on signal detection theory (cognitive focus), and working with a winbugs expansion in matlab. I am looking for good references, papers, books, anything that fully cover the theory of bayesian modeling and statistical inference (mostly with graphical modeling, since that...

I wanted to model a particular game and determine the probability for each team to win. I have no idea how to do the determination of probability part, but here's the game broken down: There are 3 types of players, T's, D's and I's. The amount of each type of player is as follows: 1/8 D...

This question is inspired by reading Arnold Neumaier's article on Everett's measurement theory: http://arnold-neumaier.at/physfaq/topics/everett Suppose I have a system whose state lies in a two-dimensional Hilbert space, and I want to model a measurement of its state as a unitary evolution...

OK, I'll dive in and start a climate change thread. I'm fascinated by the Nature paper by Abe-Ouchi, et.al., which I already uploaded in post #21 of this thread. If you look at Figure 1, the model does an outstanding job of modeling the last several ice ages. I have been somewhat skeptical of...

Dear all, I have a coupled system of ode's with an algebraic equation. The equations are as follows, function dy=lorentz(t,y) global Vfc; %fcdata.m % Data file for the hybrid system with parameters values %*************************************** % Physical parameters Rl = 0.024...

Hi there! My first post, exciting. What I'm after is a little help steering me in the right direction. I'm attempting to model evaporation in a closed system, and I'm not sure how to go about it. That is, let's assume we have a liquid in a partially filled container, and the rest is filled...

Why can't EM attraction/repulsion be modeled as spatial curvature the way gravity can be? And for that matter, why can't the strong and weak nuclear forces be modeled that way either? Or can they?

I can't model the potentiometer in speed governor control system by MATLAB even I know the input of it is pu and the output is voltage but when I run the program it has an error occur I want to see what wrong it is. Help me please

I am trying to model a shape T aperture through 2D rect functions. Both the horizontal and vertical 'lines' have length b and width a, and do not overlap. The origin should be taken to be the centre of the vertical line. The question has hinted at the function describing the aperture to be...

I would like to model rain hitting a surface and then running off of the surface. The surface would be a square, such as a slab of concrete, and the concrete would not be at any angle, so the rain would run off of all sides equally. This is a starting point for a small research project I am...

Two EE questions -- nodal analysis and circuit modeling Homework Statement Homework Equations I was given R1, R2, and Iα(t), the time for the switch to closed (50μs<=t<=100μs) The question is asking about the energy associated with 2 sources and dissipated in R1, R2.The Attempt at a...

Homework Statement I am trying to model using differential equations rain falling from the sky, hitting the pavement, and then running off the pavement into the ground. I'm a little rusty on differential equations and I'm just wondering if my answer is correct. In this model I'm assuming that...

I'm developing a scanner that uses a laser for edge detection. It will be mounted on a hexacopter that will traverse a short distance through a cave/tunnel system and produce a 3D image. I'm still researching on ways to process this data but I'm thinking of using a edge detection algorithm in...

Homework Statement Consider an item that is initially sold at a market price of $10 per unit. Over time, market forces push the price toward the equilibrium price, $20, at which supply balances demand. After 6 months, the price has increased to $15. the Evans Price Adjustment model says that...

Homework Statement Suppose water leaks out of a barrel at a rate proportional to the square root of the depth of the water. If the level starts at 36 in. and drops to 35 in. after 1 hour, how long will it take for all the water to leak out of the barrel? I have to choose and implement a...

First off, this is a typed paper project, and I am not asking for anyone to solve my work or to give me the answers. Just please point me in the right direction or help me through any parts I am not understanding. This is also a 7 part project, and I would like help on this first problem to get...

1. An object of unit mass is dropped from a height of 20 above a liquid-filled reservoir of depth 50. If the acceleration of gravity is 9.8 and the resistance-to-motion coefficients of air and liquid are 1 and 4, respectively, compute the time taken by the object to hit the bottom of the...

Hi, all. Could anyone recommend some good software for modeling nuclear physics? I have concept nuclear rocket that I wanted to attempt to model the engine for to see how practical it would be. In case it's relevant: The design is a subcritical fast dusty fission fragment reactor driven by a...

Hi there, I think this is in the right section if not please inform me and move my thread. I want to design and build a UAV in a copter format whether it be quad, hexa, octa, ect. I want to make a modeling software so that I can design the most efficient blade/motor for my specific needs. I am a...

I'm currently in the middle of a Physics PhD program but I now want to drop out with a Masters. I'm considering a career as an materials engineer or EE, but I definitely want to focus more on using software than 'hands-on' work. I heard that power systems, signal processing, communications...

Hello! I'm currently working on a project where i am supposed to model a two tank system. The only information the project gave me, was that i have to control the fluid level in tank 2 (what kind of fluid is up to me). I have tried to put the problem in a practical contex, where i have...

If g (acceleration due to gravity) was double on Earth, how tall would our atmosphere be?

For a University project I need to somehow model the effective performance of a ground grid in the event of a fault caused by a lightning strike. We would need to prepare different test cases for different sizes and grid configurations in order to carry out different analysis and find the...

Hi, I am trying to decide on a topic for my senior project, and my professor and I fleetingly discussed my idea of writing a program that models collisions of macroscopic objects using the mutual repulsive forces of their valence electrons rather than standard conservation laws. My question is...

This is a section from the Pan Air user's guide (Pan Air is a aerodynamic panel-method flow solver). I'm confused by the symmetry and anti-symmetry. The first one is easy enough: mirror about the XZ plane (Yimage = -Y, Ximage = X, Zimage = Z). The third one is no symmetry applied. Also easy...

I am doing some problems from a practice final and would like to know if the following problem has mistakes in the way it is written. It is throwing me off. **Problem statement:** Suppose that $(X_1,P_1), \ldots, (X_n,P_n)$ are independent random vectors with $X_i|P_i \approx Bernoulli(P_i)...

Hello, I'm trying to apply conservation of energy to a lightbulb circuit, but I can't think of what term should be included for heat loss / convection / conduction Here's what I've got Pin = Pradiated + i2Rwire, connections, etc + Power lost to heating surroundings? (what can I use for...

I have a copy of Pan Air (A502) which is a high-order panel method used for modeling 3D airflow around arbitrary bodies. I've read the manual, but I'm not clear about the units used. As I understand it, the free stream velocity is normalized which implies that all the other geometry is scaled by...

Homework Statement Flies, frogs, and crocodiles coexist in an environment. To survive, frogs need to eat flies and crocodiles need to eat frogs. In the absence of frogs, the fly population will grow exponentially and the crocodile population will decay exponentially. In the absence of...

Hi.. This is sundaram, I'm trying to learn state space modeling, I'm trying to model the simple RL series circuit, to control/read the current flowing through inductor. I could find the way to monitor the voltage across inductor. as below x'=(u - Rx)*(1/L) y=(u - Rx) where: x => i...

My group has given the task of modeling projection of line and my part is to construct the vertical and horizontal plane. So my idea is to have two mirrors joined like an laptop, so that we can fold them and they can also be perpendicular. I'm thinking of making hole in one mirror and a...

Hi all, I am trying to find the slope of a T-stub joint at the bolt in order to find the bending stress of the bolt. I have drawn 1/2 of the T-stub as a beam. The beam analysis requires (for physicality) that the slope at each side of the beam to be zero. There is an applied load, a bolt...

Hello everyone, This isn't really my area of expertise, so I am looking for a bit of guidance. I wish to estimate the temperature underground at a depth of 5ft. The climate is Saskatchewan (Canada) so it is covered with snow in the winter, and fairly hot in the summer. There is no tree...

Ecologists use the following model to represent the growth rate process of two competing species, x and y: dx/dt=r1x(1-x/K1)-α1xy dy/dt=r2y(1-y/K2)-α2xy Let x= number of blue whales (measured in 100,000's) y=number of fin whales (measured in 100,00's) t=time measured in centuries...

Here is the question: I have posted a link there to this topic so the OP can see my work.

An oil spill has fouled 200 miles of shoreline. The oil company responsible has been given 14 days to clean up the shoreline, after which a fine of $$10/day$ will be imposed. The local clean up crew can scrub 5 miles of beach per week at a cost of $500/day. Additional crews can be brought in at...

Model I have a simple model. Say a 1DOF-Model like a box on a table pulled with a spring, which follows a given path. The friction between box (The position is y) and the table should be modeled with the coulomb-friction model. Like F_N\mu\geq F_T \rightarrow \dot{y}=0 F_N\mu<F_T...

Consider a tank used in certain hydrodynamic experiments. After one experiment the tank contains 200L of dye solution with a concentration of 1 g/L. To prepare for the next experiment, the tank is to be rinsed with fresh water flowing in at a rate of 2 L/min, the well-stirred solution...

Hello, I am currently pursuing my degree in Mechanical Engineering, and was wondering what math courses were good to take after the basic math sequence has been completed (Calculus 1-3, Differential Eq & Linear Algebra.). I have an interest in mathematical modeling and data analysis, as...

Hello all, Would love for someone to help me get a solution for this. So, in essence I am trying to model a differential equation for the following scenario: (I am currently achieving this through Excel, but I'm certain a mathematical representation can make things more concise and...

Here is the question: I have posted a link there to this topic so the OP can see my work.

Here is the question: I have posted a link there to this topic so the OP can see my work.

Re: Are my answers correct? Quadratic and logarithmic modeling I actually have a few more things that i'd like you to check for me please. Answers: Appetizer: {0<=x<=10 y=7 x>10 y=2(x-10)+7 or y=2x-13 Quest: {0<=x<=40 y=40 x>40 y=1(x-40)+40 or y=x) Voyager: {0<=x<=60 y=60 x>60...

This is what i got... For option 1 I think it's y=( .5(x-20))^2+20 for x>20 For option 2 I think it's y=30+.5*ln|x-25| for x>25Question: develop equations that model the two replacement pack options (option 1) quedratic model, monthly access fee \$20, included gigabytes 20, cost per...

Hi math gurus . I have probability modeling question. There are 5 coins A, B, C, D,E,F . Each coin has 2 outcomes on flipping Head (H) or Tail (T). For each coin type there is a different score associated with H or T outcome. The cumulative sum of score will be recorded for the number of...

A thought crossed my mind about the idea of atomic computers. In short, I have no clue as to whether such a thing is feasible, already in the works, or just a bunch of nonsense, which is why I decided to bring it up here and see if anyone could offer some insight into this idea. If so, I’d...

Homework Statement A spherical raindrop evaporates at a rate proportional to its surface area. Write a differential equation for the volume of the raindrop as a function of time. Homework Equations Volume of a sphere = V = (4/3)πr3 Surface area of a sphere = S = 4πr2 The Attempt at a...

I was wondering if anyone has ever tried to model/fit a crack on a material surface with a Weierstrass function.

Hello all, I am trying to model a received laser signal, x(t), reflected off a moving target. I am currently trying to model for both frequency change due to Doppler shifting as well as a time-varying phase shift, θ(t), due to the continuous change in distance from the target. My current...