Hi everyone

Hi everyone,

I am unable to create the CT phantom from CT series given in release note. I followed the instruction given in ref. as bellow still I am struggling with this. Could you pls elaborate how to create ct phantom from series of ct.

I have installed virtual box inside mac OS (Mojave version) as GUI did not function properly on my Mac once I have…

I have installed virtual box inside mac OS (Mojave version) as GUI did not function properly on my Mac once I have upgraded from High Sierra. I have followed through every single steps to install in Vritual box. But while installing EGSnrc in Virtual Box, it did not create egs_home(I think it should)! Does anyone tell me where do I have errors during instaltion process? How do i able to fix it? Your feedbacks/comments are highly appreciated! Thank you!!

Hi All

Hi All,

Does anyone has a reference and/or can explain the difference between the standard deviation calculated using batch-based statistics and the standard deviation calculated using normal (history-based) statistics?

I originally thought that standard deviation calculated using batch-based statistics only depends on the number of batches and does not depend on the number of histories per batch. However, a colleague of mine told me that if the different batches calculated means that are close enough (do not have much variation), then the standard deviation of these means will be consequently small. This confused me a lot. Here is a picture of a paper I read that confirms my original thinking, but I am still confused because of my colleague’s idea.

Hi Everyone

Hi Everyone,

I’ve been trying to run egs_brachy in parallel in batch mode. I only installed ‘at’ and simply run the syntax

exb egs_brachy my_input pegsless batch=at p=n

since ‘at’ is default.

Every attempt ended with the error;

“EGS_JCFControl: failed to open job control file /home/user/../egs_bracy/my_input.lock”

“EGS_Application::runSimulation(): failed to start the simulation”

Please any help will be appreciated,

Thanks in advance

Isong

Hi everyone.

Hi everyone.

My question is following: there is any way to obtain voxelized cylindrical phantom for egs_brachy?

We have 3 geometry libraries allowed: egs_ndgeometry (XYZ), egs_rz and egs_spheres. What I want to do is to create cyliner (radius 7.4 cm, length about 2 cm) but made of rectangular voxels, like box in XYZGeometry. I thought the egs_rz geometry is what I need. But I think I was wrong, because (if I correctly understood) the egs_rz geometry creates “slices” down z-axis (and it’s ok for me) and “onion ring-like” shells around z-axis. I’m afraid it’s not exactly what I want.

And I ask my question: can I in any way create cylinder but made of little cubes, instead of set of rings like tree rings?

Hi everyone

Hi everyone,

I created an egsphant file that discribes a human phantom. For this I also defined my own media. The phantom works for the “dosxyz_show”. Now I would like to create a soucre that gives me the 3d dose of a normal x-ray photograph. I think the rectangular point souce would be good for this.

I have already created an egsinp file using the dosxyz gui, but I get an error when I choose the run option in the gui. Can you tell me where I made mistakes? I saved the files in google drive, you can see them using the link. The error_gui.txt ist the output I get when I press the “run button”.

https://drive.google.com/open?id=1oU6dA1Z4H65cpNVvTcOsyKQ8GYZwHNxr

Thank you very much for your help!

https://drive.google.com/open?id=1oU6dA1Z4H65cpNVvTcOsyKQ8GYZwHNxr//cdn.embedly.com/widgets/platform.js

Hello everyone

Hello everyone,

I am modelling my geometry in egs_chamber. I have two blocks lying one over another (see please the first screenshot). I made one block a bit longer than what it should be to avoid abutting surfaces. But when I make the other block transparent I see that my geometry is “strange” (see please second screenshot). Is this normal with egs_view or it is actually a red flag that my geometry is not accurate? Thank you very much in advance!