Category Archives: Uncategorized

Analyzing and manipulating settings.xml of LIBPF OPC

Posted on May 18, 2012 by paolog

LIBPF OPC is the LIBPF module that adds plant control system connectivity via the Classic OPC interface (OPC DA). The module is configured using the LIBPF OPC Configurator, but the underlying configuration data are stored in an XML file called settings.xml. … Continue reading →

Posted in Uncategorized | Leave a comment

Step-by-step guide: adding new files to a LIBPF project

Posted on May 15, 2012 by paolog

Reference documentation is great, but often boring to read and not helpful to solve specific problems that arise in day-to-day use. To tackle these, a step-by-step guide can be helpful. Here is one such step-by-step guide for adding a new … Continue reading →

Posted in C++, Howtos, Uncategorized | Leave a comment

The RRSB particle size distribution

Posted on April 3, 2012 by paolog

In the concrete and coal processing industries the RRSB (Rosin, Rammler, Sperling und Bennett) equation for interpolating PSD (Particle Size Distribution) curves is quite popular. The RRSB distribution is: D=1-exp(-(d/d’)^n) and has this appearance: The name RRSB is used in … Continue reading →

Posted in Chemeng, Uncategorized | Leave a comment

buildbot vs git

Posted on April 2, 2012 by paolog

If you are pulling code from a git Distributed Version Control System, then there is a known bug in older versions of buildbot, which can hit you if your git version is newer than 1.7.7. This was fixed in the … Continue reading →

Posted in Howtos, Uncategorized | Leave a comment

The open area for triangular pitch perforated sheets

Posted on February 27, 2012 by paolog

For heat exchanger tube plates and for sieve trays in columns, the triangular pitch arrangement is common. You can find ready-to-use formulas on the web to calculate the open area of a perforated sheets, such as this one on the … Continue reading →

Posted in Chemeng, Uncategorized | Leave a comment

Read Books? Why? Use internet!

Posted on February 17, 2012 by danny

Suppose you a problem to solve. Then you can call expert and pay them to solve it, or you can solve it by your own. Now suppose you are a crazy guy and so you choose the second way. You … Continue reading →

Posted in Philosophy, Uncategorized | 1 Comment

Extend the system partition in a Windows virtual machine running within kvm/lvm

Posted on February 6, 2012 by paolog

You have that Windows 7 or Windows XP virtual machine and you are running short of system disk size. So you wish to extend it without rebuilding the virtual machine and with no risks ? The following applies if the … Continue reading →

Posted in Howtos, Uncategorized | Leave a comment

Is open source an option for process simulation software ?

Posted on January 30, 2012 by paolog

This is an updated version of the forum entry titled “Is open source appropriate at all for chemeng software ?” which was posted here 5 years ago; that forum seems abandoned nowadays, but the topic is still relevant so I … Continue reading →

Posted in Chemeng, Philosophy, Uncategorized | Leave a comment

Innovation in numerical analysis

Posted on January 5, 2012 by paolog

Innovation does not stop in the field of numerical analysis, which lies at the heart of industrial applications of numerical simulation and modeling. In this regards the recent paper “Multifrontal Factorization of Sparse SPD Matrices on GPUs (ACM)” by T … Continue reading →

Posted in Chemeng, Philosophy, Rants, Uncategorized | Leave a comment

Accurately measure execution time in Windows 7

Posted on May 16, 2011 by paolog

While UNIX has a shell command to measure execution time (it’s called time, and it’s been there rock-steady since 1990), Windows by default doesn’t. The right answer to the question “how do I accurately measure execution time in Windows XP’ … Continue reading →

Posted in Howtos, Uncategorized | Leave a comment