A model is an informative representation of an object, person or system. The term originally denoted the plans of a building in late 16th-century English, and derived via French and Italian ultimately from Latin modulus, a measure.
Representational models can be broadly divided into the concrete (e.g. physical form) and the abstract (e.g. behavioural patterns, especially as expressed in mathematical form). Of particular importance in the modern context, conceptual models are central to philosophy of science, as almost every scientific theory effectively embeds some kind of model of the physical or human sphere.
In commerce, a model might instead reference a specific version or configuration of a product offering, rather than functioning as a representation of something else.
In taxonomic settings (e.g. biology, architecture, art) a model is sometimes a particular instance of a set of related entities (species, built structures, artistic compositions) chosen as a convenient reference point around which to build discourse; such a model is almost always chosen to typify some central tendency of the group, exemplify the group's defining characteristic, or reify the group's historical lineage.
Kinds of models include:
The independent particle energies for protons and neutrons around the
exotic doubly magic core 132Sn are shown in the figure below, where
π refers to protons and ν to neutrons.
Using the nuclear shell model and using this figure as a guide, answer
to the following questions:
a)Estimate Jπ...
Is the Standard Model overfitted? I hear that the standard model is the most accurate model that we have so far showing accuracy of 13 digits or so. However I am wondering if this accuracy comes from adding so many constants until it fits.
First of all the standard model takes in 25 constants...
$$H = - J ( \sum_{i = odd}) \sigma_i \sigma_{i+1} - \mu H ( \sum_{i} \sigma_i ) $$
So basically, my idea was to separate the particles in this way::
##N_{\uparrow}## is the number of up spin particles
##N_{\downarrow}## "" down spin particles
##N_1## is the number of pairs of particles close...
What is a "transient" value, result, or state in the Ising model?
How do we treat these values during the simulation?
Do we discard these values? If so, why?
Hello everyone,
I would need help to model a motorized system controlled in a closed loop. It is a personal project.
At first, I am looking to obtain the transfer function and simulate the system on computer. In a second step (not the aim of this thread), I would like to use this simulation to...
In Simulation of transformer and electrical motors in software like ansys maxwell we usually have to model conductors, but does it matter how to draw them?
I use Ansys software for finite element simulations. Maxwell, Simplorer, RMXpert and other toolboxes. but I always have a doubt on how to...
Hi PF!
Given random time series data ##y_i##, we assume the data follows a EWMA (exponential weighted moving average) model: ##\sigma_t^2 = \lambda\sigma_{t-1}^2 + (1-\lambda)y_{t-1}^2## for ##t > 250##, where ##\sigma_t## is the standard deviation, and ##\sigma_{M=250}^2 =...
I need help trying to model this true anecdote.
Every nice weather day, I like to climb a mountain. It takes a 40 minute drive to get there, 40 minutes climb up, 10 minute break at the summit, 30 minutes down, and 40 minutes drive home. 160 minutes total. On the way home, I repeatedly meet...
Dear Mr. and Ms.,
I am trying to measure the autocorrelation functions of 2D ising model based on the equation given by
where A(t) denote a measure. I calculate a c(t) of magnetization. I calculated in this way
data_path = f"../../trajectory/data.txt"
data = np.loadtxt(data_path)...
I have recently studied the slow-roll inflation model. In it, slow-roll inflationary conditions are mentioned in a lot of places(these conditions needed to be satisfied for inflation to happen). I don't really understand the meaning and purpose of slow-roll inflation. I want to know a very...
Hello all,
Is there software that coverts a 2D part print to 3D Cad model with PMI?
If you have a hand drawn mechanical drawing , 'blue print" part print with the classic human drawn tolerancing, can it be scanned to software to make a 3D CAD model with all the PM!?
thank you
rm
Design the markov model and transition matrix for the given data. Answer the following questions based on the mode.
a) If a person purchase coke now the probability of purchase of coke next time is 80%.
b) If a person purchases pepsi now the probability of purchasing pepsi next time is 70%...
Design the markov model and transition matrix for the given data. Answer the following questions based on the mode.
a) If a person purchase coke now the probability of purchase of coke next time is 80%.
b) If a person purchases pepsi now the probability of purchasing pepsi next time is 70%...
I have run into a problem when trying to model a simplified vehicle that has three degrees of freedom – roll, vertical and lateral motions. It is represented by a single mass with two links that model the suspension behaviour. The links connect the tyre-to-ground contact points (tc) to the body...
Hi everyone, I'm making a fuel assembly model and I would like to have a cylindrical gamma source on each fuel rod to measure the decay heat of a fuel assembly but I'm struggling to define the source since it is in a repeated structure. This is the geometry of my model:
Level 2 : cells 1, 2 3...
Hello :
Have a question regarding the mathematical model of reflective curve where could i find information on it ? (pdf , webpages , ebooks ,...etc )
Other than Wikipedia
Best Regards
HB
Been a long time I studied physics that had anything to do with mechanics, so I'm now in need of memorizing almost everything. So I am seeking for some guidance here. This is "system simulation/modeling/discrete event system simulation/etc" type of subject.
The first thing that I didn't...
Hi PF!
A circular cylinder contains an inviscid liquid, which is softly disturbed (i.e. velocities are small). There are no body forces, which implies the equilibrium free surface is that of a spherical cap with radius ##R## (see figure A). Inviscid implies we can assume potential flow, such...
Consider a container filled with two essentially incompressible liquids with densities ##\rho > \rho'## and (respective) volumes ##V##, ##V'##, rotated by a centrifuge in some orbit-based space lab to maintain a roughly constant (co-moving) simulated "gravitational field" g. Let's suppose that...
Source: https://en.wikipedia.org/wiki/OSI_model
Source: https://en.wikipedia.org/wiki/OSI_model#Layer_architecture
It is said above that the model partitions the flow of data into sever abstraction layers.
The following is my own understanding of OSI model as a layman. For a sender, the data...
Hello.
I'm writing my Master Thesis about planetary population synthesis and one of the chapters is about the different models.
I found that most of them are Bern models with some modifications.
What is a Bern model in planetary population synthesis and what references can I read about it...
So I'm looking at the book "Equilibrium Statistical physics" by Plischke and Bergersen. I'm doing the calculation of the specific heat of the 2D Ising model. I can't seen to quite get out the same expression as in the book - there are a coupe of minus signs that are different. I don't know if I...
Homework Statement:: I would like to know how to probably vary the motor capacity or battery in that case to ensure that the plane takes off. In the attached link- the plane did not take off.
Relevant Equations:: Physics
Kindly find the link of a video on the same- downloaded from Youtube.
If the standard model Lagrangian were generalized into what might be called "core capabilities" what would those capabilities be? For example, there are a lot of varying matrices involved in the standard model Lagrangian and we can generalize all of them as the "core capability" of matrix...
In the last few years, many of us have heard of GPT-3, a "language model" trained on terabytes of Internet prose, with a remarkable ability to generate essays, dialogues, and other original works. There is a similar but less powerful model called GPT-J which can be accessed freely at the...
Hi,
I am willing to simulate a 3D ferrite bar transmitter and reciever where coupling coefficient k and Bt magnetic flux density on the each side uses the finite element method for solving partial differential equations.
The Magnetic Fields module has equation (jωσ − ω2ε0εr)A + ∇ × H = Je...
Edit: I've been catching errors I've made in the transcribing the formulas into latex ( not errors I made in the actual model..yet ). There may be more. I did this in one sitting.
I've been trying to model a bottle rocket (water propellant, compressed air fuel) and my model seems ok for a...
hi,
i have studied Standard Model for particle physics - at present it is described by three groups -
i have studied - these groups but could not establish what particular feature suggest of these group to be used to describe SM.
Thanks
Hello all,
I have written a VDM for my Masters thesis, unfortunately, since I am from a discipline other than mechanical engineering I don't have access to reliable validation material or a way to produce it (moreover, we don't have an actual vehicle testing lab/area at the U that I know of)...
This is a bit of a multi-part question on impact engineering and FEA usage.
I am working on making my Alumina ceramic model as accurate as possible in ANSYS for impact simulations. But I am noticing a common theme, while using model parameters in scientific journals I am not getting any...
hi guys
I am recently taking a Nuclear structure course, and have a lot of questions regarding the nuclear rotor model.
in most nuclear physics books the I have, the wave function associated with the rotor model of the nucleus is written in terms of the Wigner D functions , like the expression...
For the fluid, I will use three conservation laws for mixture quantities (mass, momentum and total energy) and an additional equation for the void ratio (as explained in the paper "Modeling for non isothermal cavitation using 4-equation models"). If you want I can share the explicit equations...
How to determine whether a cosmological inflation model (say single-field slow-roll inflation) gracefully exit or not? Is it like showing that inflation is ending at some value of inflaton?
Reference:
https://scitechdaily.com/breaking-cosmology-too-many-disk-galaxies-a-significant-discrepancy-between-prediction-and-reality/
The following are quotes from the reference.
1. The Standard Model of Cosmology describes how the universe came into being according to the view of most...
Hey there, I'm working on an MCNPX modelling for SCWR using different clads and fuels, the first fuel was UO2(5%) and I have calculated the number density correctly since there was only one vector U.
But now I don't know how top deal with the Th+U233 due to the existence of Thorium.
Can anyone...
Hey! 😊
In a supermarket, there are the following relationships: For each employee (Angestellter), there are employee numbers (AngNr), last name (Name), first name (Vorname), address (Adresse) and department (Abteilung) known. Each employee works in exactly one department. Of each department...
Hello, I am a student who started studying MCNP. I'm not used to writing in English, so I'd appreciate it if you could understand even if there were grammatical errors in my thread.
I want to check the energy of gamma rays from neutrons reacting with matter. So, I wrote this in the content of...
Greetings Good People,
As the title suggests, I'm having some trouble getting to a 2D model. The process is to select an aircraft (or wing model), and model it as a 2D, 2DOF wing-tunnel model.
The aircraft I selected was a Cessna 172. This had a tapered wing, which after some calculations and...
Good morning,
I continue to try to understand the collapse and fragmentation of a molecular cloud.
I was focused on the Jeans law.
I would like, now to understand the difference between this Jeans law and the Bonnar-Ebert model.
Are they complementary ?
Thanks for your help
Hey all,
I am looking forward to knowing some software/sites that show an extensive collection of the DSOs. I want it to be 3D, but it can also be 2D. I know/tried some of these,
Stellarium - 2D
Celestia - 3D
https://www.legacysurvey.org/viewer#IC 2095 - 2D
Gaia Sky (I have tried to download...
I am new to EMI modeling and just looking into it. I would like to create a circuit schematic to represent the inductive and capacitive coupling paths in one schematic. All that I've been able to find online is references discussing each independently. Is this the best approach if you want to...
Been researching armor piercing mechanics but I can't seem to find a reliable model for hand calculations. What makes matters worse is I don't know the correct value for the design I am studying. Only 3 formulas gave me similar results: NAVY 1940's "Universal" Formula, Original F-Formula, and...
Hi!
Water is flowing in a converging duct, with the angle α, see the figure.
My task is to find a real-life phenomenon / application of this model, and later solve it numerically / analytically where this fluidproblem occurs. However, my imagination is kinda slow today, what are some fun /...