Category Archives: Text

How-tos, software recommendations, code snippets, my opinion on stuff.

Subcategories: Energy, How-tos, Linux

Random Dilbert bookmarklet

I’m addicted to the webcomic Dilbert by Scott Adams. He publishes one comic strip a day. With its archive ranging more than twenty years back, a random function to discover new old comics would be quite handy. That is what the following code snippet does: Create a random date between January 1st 1990 and today and navigate to that day’s comic address:

javascript:function pad(n){return n<10 ? '0'+n : n} var now = Date.now(); var offset = (new Date(1990, 01, 01)).valueOf(); var rdate = new Date(offset + Math.round(Math.random() * (now-offset))); location.href = 'http://dilbert.com/strips/comic/' + rdate.getFullYear() + '-' + pad(rdate.getMonth()+1) + '-' + pad(rdate.getDate()) + '/';

Just copy the text and add it as the URL to a new bookmark called “Random Dilbert”. Whenever you click on it, it takes you to a different comic.

How to convert video to MPEG 422 HD format for import in Lightworks Free

The best freely available video editing software for Windows is Lightworks (version 11.0.1). While it is free (as in beer), it has very restricted selection of import video formats at the moment. My camera (Canon EOS D550) delivers H.264 encoded MOV files, which—without other software—would require a 50 €/year codec license if you want to import them directly. Fortunately, I found a way to import my videos… Continue reading

DESERTEC studies: AQUA-CSP

AQUA-CSP is one of three conceptual studies which explored different parts of the DESERTEC project, a concept which relies on solar power from the world’s desserts as a major energy source for Europe. In previous posts I already talked about the two other studies MED-CSP andTRANS-CSP, the first focused on generation, the second on transportation of the generated electricity. This article deals with the third, often overlooked, aspect if this undertaking: desalination of huge quantities of sea water. Continue reading

Optimise nonlinear functions using Matlab or Octave

Contour plot of a test function. In the middle its minimum is shown. White triangles are spread throughout the picture, denoting the locations of the initial simplices.

For my diploma thesis I needed an easy-to-use optimisation algorithm which could minimise a given function. I had access to Matlab, but surprisingly, none of the supplied optimisation functions seemed to satisfy my needs: I wanted to globally minimise a non-linear function within boundaries without using gradients.

So I did a little research and found a Globalized Nelder-Mead method (PDF), which is a tuned version of the good old downhill simplex algorithm. Then I implemented it as a Matlab function. By the way: the function also works fine with Octave. Continue reading

Mathematical Formulas in Microsoft Word

Formula typesetting can be a tedious work in most typewriter software. Word (here: Version 2003) is no excuse. When you are — like me — forced to use this software for writing technical reports containing formulas, then this tip might be useful for you. The “typical” way of writing formulas is creating formula objects which can be edited by a double click on them. However, as soon as a document contains many of those objects, their handling becomes uncomfortable because they don’t behave like their surrounding text.

But there is another, almost perfectly hidden feature which allows to typeset easy formulas as real text which respects text formatting styles: Equation fields. Continue reading

DESERTEC studies: TRANS-CSP

In a previous post I wrote about MED-CSP, a study being part of the DESERTEC project which outlines a scenario for generating huge amounts of electricity by means of Concentrating Solar Power applied in the Mediterranean region. CSP stands for solar thermal power plants which do not operate with the photovoltaic effect used in solar cells, but for using the solar radiation to directly heat a medium—typically a fluid—which then is used to propel an ordinary steam turbine like used in fossil fuel or nuclear power plants.

While the last post focused on the MED-CSP study which explores the technical potential for generating electricity, this article deals with the transmission of a part of this energy to Middle and Northern Europe where it can substitute fossil fuels. Continue reading

DESERTEC studies: MED-CSP

This article originates from a presentation given by Hani El Nokraschy, one of the leading persons of the DESERTEC foundation. He presented the foundation’s vision towards a sustainable generation of electrical energy and drinking water around the Mediterranean Sea for Europe, Africa and the Middle East. His presentation covered the three main studies called MED-CSP, TRANS-CSP and AQUA-CSP. CSP stands for Concentrating Solar Power and is the key technology for exploiting the huge potential of solar energy that shines on Africa’s deserts. Continue reading

How to use custom-made Themes under Windows XP/Vista/7

Deskmodding is the art or the act of customizing the appearance of the graphical user interface. Usually this is done on the level of the operating system, but there are also single applications that allow to modify their appearance by so-called skins. For the operating system Windows it is not possible to easily change the default appearance as the selection of themes that can be selected is limited to a handful of designs like the classic Windows interface, Luna for Windows XP and Aero since Vista. Windows Media Center Edition brought a revamped version of Luna which became very popular.

But apart from those designs, Windows does not permit to select user-made themes. This is due to a check in the file uxtheme.dll in the system32 folder. There are dozens of downloads of patches that promise to replace the file with a patched version that permits so select whatever style one prefers. But it is easy to download the wrong patch or even get a virus on one’s computer this way. But there is an alternative: UxStyle. Continue reading