How to access the generation of the population in fitness function while using gamultiobj in Matlab?

I have running GA optimization using "gamultiobj" in Matlab. The upper bound and lower bound of my design variables are like [10 30 175 1] and [30 60 225 3]. But after convergence, I see the design variables (like all of them) near 20,47,175 and 1. I am not getting a Pareto Front. What could be the possible reasons for that?

Hello everyone,

i'm applying gamultiobj (Multiobjective optimization using genetic algorithm) from optimization tool of matlab

* how do i export the results frome and to command window?

** is it possible to apply gamultiobj for fitness function who has 3 objective functions?

plz it's urgent .. i need answers ^^

Hello, I have another questions for the experts who are all giving much great advice on multi-objective optimization.

I have another problem, a bi-objective one so that I am planning on using the much used NSGA-II to solve it.

I am trying to decide the parameters(population, iteration, mutation, crossover rate) and was wondering if people could direct me as where best to start or maybe the most recommended default setting.

For example, I have seen a lot of paper with population 20~100, generations 500, mutation=0.1 or less, and crossover=0.9 .

I am thinking of starting with these (with population 100). Do you think that its okay?

Also, could anyone suggest any papers as to why these figures are so often used?

Also, I am thinking of working my way through a sensitivity analysis where I change the parameters a bit as recommended by other answers.

How do I know how much to much the parameters by and how well the algorithm is performing? 

If it helps, my optimization problem is

Objective functions f(x,y,z)

Minimize 0.210/x + 0.067/y+ 0.001/z+ 0.443/x*y+ 0.0006/x*z+ 0.010/y*z+ 0.160/x*y*z

 and

Minimize 33*x+ 1*x*y+1*x*y*z

Variable Bounds:

x= 15~268

y= 2~15

z= 2~15

Constraint:

x,y,z are all integers

Thank you all in advance for all your help.

I am modelling a hyperelsatic and viscous material in ABAQUS. I have calculated the hyperelasticity parameters using curve fitting. Now, for viscoelasticity, I have stress relaxation results in terms of shear modulus variation with time. While inputting the data into Abaqus, you need two parameters G0 and Ginf along with the experimental results. So i think G0 is the shear modulus at the beginning of relaxation test and Ginf is defined based on hyperelastic parameter(2*C0 for Yeoh Or similar for other models)? Am I correct or else?

One of the reviewers of my recently submitted paper seems to have written the review using ChatGPT.

I am, of course, willing to revise the paper if the content of the review is appropriate.

However, none of the 9 revision requests in this review are related to my paper.

In this case, how should I respond? Should I write a letter to the editor?

Hello there! I am running transient CFD simulation for a vehicle ideal gas law and the energy equation and I seem to be getting a negative gauge static pressure in the whole domain, even though the reference pressure in the domain was initialized to the atmospheric pressure. Does anyone have suitable explanation and a possible solution for this occurrence? Thanks!

My university doesn't allow the New mendeley reference manager word plugin to be installed on the work computer. However, if there was an exe file for the plugin, this could be bypassed. Any ideas/suggestions welcome. Thanks in advance.

Hello,

I have modelled a frame with leaning column. But I have chosen the coordinates ZY as primary (2-D) so Z coordinate represents horizontal direction and Y as vertical. I want to know if Abaqus converts these coordinates into XY and then the output results would be based on the global coordinates that Abaqus has defined or converted it to?

For example, I might have got results for the analysis of the frame in following manner:

Reaction Forces - RF1, RF2, RF3

Displacements - U1, U2, U3

Moment - SM1, SM2, SM3

If I have applied a horizontal load on left column and I want to look at horizontal reaction then do I have to see RF1 or RF3 results? When I saw the .dat file the reaction force that I was expecting was in RF1. So does that mean Abaqus is converting the coordinates into Global coordinate system or not?

Any sorts of help/opinions would be appreciated.

Thanks!?

I am trying to model fatigue crack propagation using XFEM in Abaqus and I observed that I could create three types of steps for this task: static-general, dynamic-implicit and direct-cyclic. What is the difference between using one type of step or the other for the model? Thank you for your help.