Parameters Definition and 489 Threads

do we have laws of nature discovered that form a set of equations which use different formula in different set of parameters?

This isn't intended to be a discussion of the philosophical "fine tuning argument", rather, I'm hoping to fact check myself as to what is meant by "fine tuning" in physics. My understanding was that fine-tuning is the process in which parameters of a model must be adjusted very precisely in...

i need to write a function for DPI screen scaling, so the parameters is from 100 (percentage) to 350 (percentage) and increases at 25 (percentage) increase, it will subtract additional 1 DPI so for example: 100% = 96 DPI which is -4 125% =120 DPI which is -5 150% =144 DPI which is -6 175%...

Assume that players A and B play a match where the probability that A will win each point is p, for B its 1-p and a player wins when he reach 11 points by a margin of >= 2The outcome of the match is specified by $$P(y|p, A_{wins})$$ If we know that A wins, his score is specified by B's score; he...

I have been trying to build a simple Current control circuit using a NPN TIP35C transistor but have run into the problem of it constantly over heating and being destroyed. The transistor is the only component that heats up whilst it is on. The supply voltage is 10V, well below the Max and at the...

Hi all I was reading a certain paper that involves solving the Bohr-Mottelson Hamiltonian for a 5dimential square well potential, the B-M Hamiltoian reads: my question is just how do I calculate the mass parameter "B" for a certain nuclei, and with a 5D infinite potential well how do I get the...

How to set the parameters - photon index and metal abundance in the CIAO-sherpa tool for an x-ray source?

On page 160 in Shankar, he discusses how we get quantized energy levels of bound states - specifically for the particle in a box. We have three regions in space; region I from ## \ - \infty, -L/2 ##, region II from ## \ -L/2, L/2 ##, and region III from ## \ L/2, \infty ##. For the...

Dear friends, I will be grateful if anyone can help me I study electromagnetic scattering by rough surfaces for a certain case. Each rough surface can be specified with the statistical parameters sigma (σ) and correlation length (lc). while writing my manuscript I drew a schematic...

I would like a program to read in a file entered by the user via the command line, which is then used in the main body of the code. See example code below: #include <iostream> #include <fstream> struct run_t { std::string file; }; run_t run; const POINTER* ptr = toy(run.file,0); int...

Hi, Due to a proxy issue I have to launch chromium with this additional requirement to set the right proxy chromium-browser --proxy-server=http://proxy.myproxy:XXXX To get things more easy I defined an alias alias chrome='chromium-browser --proxy-server=http://proxy.myproxy:XXXX' so now I...

It is often said that one of the drawbacks of the standard model is that it has many free parameters. My question is two-fold: What exactly is a free parameter? My understanding is that the free parameters of a model/theory are the ones that cannot be predicted by the theory and need to be...

Hello, I am looking for a reference which describe perturbation theory with two parameters instead of one. So far, I did not find anything on the topic. It might have a specific name and I am using the wrong keywords. Any help is appreciated. To be clear, I mean I have ##H =...

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I am looking at a solar panel and would like to be able to plot the IV curve for it. I have Isc, Voc, Imp, and Vmp from the datasheet so I can get the fill factor. I know each cells dimension and the number of cells too so I can find the current density if required. Is there a way to use the...

Hi everyone, Imagine I have a system of linear differential equations, e.g. the Maxwell equations. Imagine my input variables are the conductivity $\sigma$. Is it correct from the mathematical point of view to say that the electric field solution, $E$, is a function of sigma in general...

I apologise for cross-posting - I've already posted this question on CrazyEngineers but have had no replies after a few days and I was wondering if someone here could help me: In my current job, I am responsible for maintaining an existing software application that generates a dressing program...

I am having trouble to understand what it means by "physically relevant real parameters" and how does it help us to specify a quantum system. Let say, we have a state of k half spin electrons? My guess is about the local phase of the spin, and this would make it 2^k parameters since each...

Hello community! I am facing a conceptual problem with the correlation matrix between maximum likelihood estimators. I estimate two parameters (their names are SigmaBin0 and qqzz_norm_0) from a multidimensional likelihood function, actually the number of parameters are larger than the two I am...

In cosmology, CMB tells a lot about which cosmological model can be acceptable or not. For instance we know that, whatever the cosmological model we use ##\theta_*## parameter will be always the same. Is there any other parameters that is listed in this picture is **model-independent** ?(i.e...

I want to understand the parameters of the synchronous motor Rated Power -> This is the maximum power the motor can deliver -> Is it correct? I can operate the motor for any power less than this? Rated Torque -> This is the maximum torque beyond which the motor cannot produce? Rated speed ->...

Hallo at all! I'm learning statistic in python and I have a problem to show you. I have this parametric function: $$P(S|t, \gamma, \beta)=\langle s(t) \rangle \left( \frac{\gamma-\beta}{\gamma\langle s(t) \rangle -\beta}\right)^2\left( 1- \frac{\gamma-\beta}{\gamma\langle s(t) \rangle...

I have to study the solutions of the following system of three equations and three unknowns upon variation of parameters k and h. ix1+kx2-x3 = 1+i (k+i)x1+(1-i)x2-(ik-1)x3 = h kx1+(4+2i)x2-(k-3-3i)x3 = 1-i Obviously i is the imaginary unit. And as stated k and h are the parameters . I can't...

Matrix multiplication is defined by \sum_{k}a_{ik}b_{kj} where ##a_{ik}## and ##b_{kj}## are entries of the matrices ##A## and ##B##. In definition of orthogonal matrix I saw \sum_{k=1}^n a_{ki}a_{kj}=\delta_{ij} This is because ##A^TA=I##. How to know how many independent parameters we have in...

L = mvr = mr (dr/dt) = 2m*r*(dr/dt)/2 = 2m*(dA/dt) So, A = (L/2m)T so, ## L = \frac{2 \pi a b m}{T}## Now, ##T^2 = \frac{4 \pi^2}{GM} a^3## So from all these, I get ##L = \sqrt{ \frac{GM m^2 b^2}{a}}## But answer given is ##L = \sqrt{ \frac{2GM m^2 ab}{a+b}}## (This, they have derived from...

There is this argument that any new forces of nature or any new interactions would have very small gap of space left in the experimental space or parameter. The argument being that for every force, there is a particle and a field, and virtual particles. And the virtual particles can affect...

In cosmology the deceleration parameter defined as the $$q_0 = \frac{1}{2}\sum_i\Omega_{i,0}(1+3w_i)$$ Is there a similar expression for the jerk parameter (##j_0##) ?

i have drawn the E field as below, hence the F will be in the upward direction for electron a. Using energy is constant, the velocity ##v_x## as it crosses A is ##0.5mv_x^2 = q*V_a## ##v_x = \sqrt{(\frac{2qV_a} m)} m/s## one doubt i have here is, the question mentions electrons, but i have...

I have a Gaussian function of the form: def f(x,y): a=some number b=... c=... return 3*np.exp(-a*(-0.5 + x)**2+b*(x-0.5)*(y-0.5)-c*(-0.5 + y)**2)This is a Gaussian function symmetric around y=x, and I'd like to rotate it 45 degrees (counter)clockwise. Wikipedia gives an overdetermined...

I am interested in research on hybrid rocket technology and I would like to know if anyone has a known ideal way to measure the required parameters to find the below items. I am particularly interested in a cold flow test involving: Characteristics of the Oxidizer Flow Turbulent Intensity...

What is most important parameter when we must build long last internal combustion engine and why? specific output : HP/Displacement ? HP per each cylinder? Torque per cylinder? Displacement per cylinder? HP / piston area ? RPM / displacement of one cylinder? Numbers of cylinder? Low RPM as...

Namely, in the system, I have obtained the value of parameters L, M, A and D, because I treat the other organism as equal to zero, i.e., it doesn't exist, but I am struggling about the values of B and C, that are coupled with the product of x and y. Can anyone help me how to obtain those values...

By rearranging over and over ratio formulas involving frequency, speed and wavelength, I came up with the equation: fP/fQ=10^-8xVP/VQ This led me to take into account only rows A, B, E, and F... but I can't really understand which one of these is the right one.

I am afraid I had no credible attempt at solving the problem. My poor attempt was writing the matrix ##\mathbb R## as a ##3 \times 3## square matrix with elements ##a_{ij}## and use the matrix form of the orthogonality relation ##\mathbb R^T \mathbb R = \mathbb I##, where ##\mathbb I## is the...

I attached a file with some explanations of the variables in the code and the plot that I should get. I don't know what is wrong. Any help will appreciated. from scipy.integrate import quad import numpy as np from scipy.special import gamma as gamma_function from scipy.constants import e...

I am wondering if it is possible to determine the covariance, ##\text{Cov}(a,b)##, of two fitted parameters given I know their explicit relationship ##a=a(b)##? I would like to construct the covariance matrix in the space of the parameters ##\left\{a,b\right\}##. Using the relationship...

If a perfect transmission line is lossless, then would the S parameter for a perfect transmission line be ? Homework Equation: S parameter matrix

The interaction of neutrinos should be proportional to the amount of material that it goes through. If i want to calculate the number of interactions that i could expect when a neutrino beam go through different materials, the first thing that comes to mind is the nuclei of the targets, as the...

5 links (thus 6 frames) and corresponding theta, alpha, d and a values are all given. However, I'm not sure how to start coding the DH parameters to derive a forward kinematics model. I know that I'll have to use matrix operators, but do I just put in the values of the 4 factors mentioned above...

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That was my attempt , but I am not sure if my answer is correct or not . I want to confirm it .

The universe after the big event was a lot of lifeless stuff. However, as things settled down the rules behind the curtain were such that life was allowed to develop, they may have even been such that they encouraged the things to happen that were conducive to the process that has resulted in...

I'm trying to do a fairly complete system analysis script in Octave that involves these steps: 1) Assign values to all fixed system parameters 2) Make various preliminary calculations based on system parameters 3) Solve a system of differential equations 4) Make various post-ODE solution...

I would like to know parameters of this material, such as: ##\epsilon##, ##\mu## and ##\sigma##, for EM simulations with CST. I can't find anything similar to carbon fibers or general plastic in the CST material library. Google is not helping me this time. Does anyone know something more on this...

It is a common center-tap transformer which is electrically demonstrated as in figure (ideal one); In my opinion, open circuit and short circuit tests cannot be applied directly. How can I place secondary reactances ? And how can I test its all parameters in laboratory ?

An electromagnetic wave has a phase speed and a group speed. Or velocities, for that matter. In a medium, the phase speed of a wave is generally determined by the medium's permeability μ and permittivity ε. What are the general parameters that determine the group speed of a wave in a medium?

Hi all, I have experimental nuclear magnetic resonance data that describe T2-relaxation of the nuclei in the sample of interest. The experimental points obey bi-exponential dependence: I = I1*exp(-t/T2_1) + I2*exp(-t/T2_2), where I is current intensity, I1 and I2 are intensities which represent...

It is obvious that there is a one-to-one relationship between real numbers (defined to include infinity) and their multiplicative inverses (assuming we map the inverse of zero to infinity and vice versa). Thus, one should be able to replace the distance between two points in space with it's...

Dear all, I am momentarily designing a robot arm and I will use the Denavit-Hartenberg convention to model my arm (see picture). The problem I have, however, is that I cannot seem to define the robot arm in the parameters of a, d, alpha and theta. It could be that my coordinates are not...

Hello folks. Normally if you have two variables and you want to know their relationship, you can plot them to get an idea of the equation that might relate them. If you see a straight line you can use the least squares method to find the best equation. You can use this method for polynomials...