All of a sudden there was this idea of building a sundial. Of course one could simply buy one. But manufacturing a sundial by oneself is a delightful and challenging combination of sophisticated calculation and manual fabrication. It is simply a wonderful project which brings a lot uf fun and exciting challenges and ends with a visible and touchable result. And a sundial mounted on the front of a house is an attractive design element and eye-catcher.
In our internal network I rely fully on Voice-over-IP for telephony services. The switching of calls is accomplished using the Asterisk software. Asterisk runs on a virtual Ubuntu server which is hosted on my own Openstack cloud server.
The connection to a standard landline works via VoIP to my provider Deutsche Telekom. My Asterisk server directly connects to their VoIP servers.
Once you have made it to eventually set up a running configuration and are looking back it seems not too hard to get this to work. Of course things will look differently after you have spent hours reading poor and incomplete documentation, trying out things which just don't work. On the following pages I will describe how I did it and what works for me, in the hope that somebody else may find it useful.
This project is about the control of our heating system with the programmable universal controller UVR1611, manufactured by the company Technische Alternative. This controller provides many different options and ways to solve any kind of control problem. And it always tempts you to constantly optimize the selected approach and search for an even more optimal solution to the control problem of heating systems, solar collectors systems and many more. This project for me brought a lot of fun and also some challenges and gained me many valuable insights into automation, controller technology and HVAC systems.
AQUILA is a 2D-Schrödinger-Poisson solver based on Matlab. It is designed for the simulation of the electronic structur of low-dimensional GaAs/AlGaAs heterostructures. This software is a spin-off of my PhD work. I wrote it as a "Quick-Hack" because similar software for two-dimensional calculations of quantum semiconductor structures at this time was not available or at least not easily accessible. The first version of this software is from the year 2000 and hasn't been modified much since then because I'm out of the semiconductor business for quite some time and so the software has aged naturally. Fortunately the laws of physics dont't change that rapidly, although in the meantime other topics have gained more interest than this one.