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Articles about miscellaneous

  1. A new STL convertor added

    In addition to stl2pov, I've now written a program that writes a shaded projection of the STL file (along the z-axis) as a PostScript file. It supports arbitrary rotations of the STL file around x-, y- or z-axis and automatically centers the object in the view, so you can ...

  2. stl2pov rewrite

    Python logo

    On 2011-04-04 I re-wrote my parser for STL files in Python. The original C parser was 411 lines (excluding comments and blank lines). The new parser in Python is 134 lines. This is also without comments. It took me about two hours to write from scratch. But that includes debugging ...

  3. Learning Python

    XKCD python strip

    Over the years I've heard a lot about the Python programming language. Now I have decided to start and learn it. I'm already reasonably fluent in languages like Perl, Lua, C and Bourne shell. But each of those feels like it's lacking somewhat. Building and maintaining versions ...

  4. About personality traits

    The following I posted as a comment on a walden effect blog about personalities. I thought is was worth repeating here.

    As for some personality being a blessing and a curse; personalities are complex. I dislike A/B and other personality labels; they're too symplistic IMO. There is no ...

  5. Additional close-up photos

    The picture below on the left shows a close-up of the surface of a carbon fiber and epoxy resin laminate. On the right is the same surface after sanding. Sanding exposes the fibers in the laminate, creating lots of places where glue can seep between the fibers creating mechanical adhesion ...

  6. Surface energy

    When investigating a bonding problem at work, I made this picture of a water droplet resting on a carbon fiber and epoxy resin laminate, to measure the contact angle, which is an indicator of surface energy.

    water droplet on a carbon-fiber epoxy laminate

    This particular laminate turns out to have a low surface energy; it does not ...

  7. Me at work

    It occurred to me that I only rarely have a picture taken with me in it. Usually I'm the one holding the camera. So here are a couple of "action shots". :-)

    R.F. Smith performing a flamability test R.F. Smith during infusion of a first prototype

    The first picture is me doing an informal test to see if a material that we made is ...

  8. XZ compression

    With the release of FreeBSD 8.1, the xz compression program has been imported into FreeBSD. I decided to do some testing to compare it to the bzip2 format. In this test I've used the standard non-multithreaded implementations of these compression programs.

    tukaani logo


    First I compressed my procmail logfile ...

  9. Visit to the JEC in Paris

    With a couple of colleagues, I visited the JEC show again this year. Most of the suppliers of the composites industry have a stand at this exhibition. So it is a good opportunity to visit those whom you know, and to spot new ideas.

    The picture below was taken from ...

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