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I write, therefore I am

With this variation on a famous statement by the philosopher Descartes, I would like to express that the act of writing about what happens in my life is important to me.

Monday, December 11, 2017

Hail, snow and rain

Around four in the afternoon, it started to hail. The hail was quite fine, but still hurted when touching the skin. After about twenty minutes the hail changed into snow. About an hour later it changed to rain. In the west of the country there were a lot of traffic jams and problems with trains. In the middle of the country 44 cm of snow was measured at one location.

Sunday, December 10, 2017

Snow and rain

In the afternoon it snowed. At the end of the afternoon, it started to rain. While biking around the city I encountered three instances where cars (and one city bus) had hid each other. In all cases, the damage seems minimal. I also one time encountered a car slipping. In the evening, most of the snow on the roads had disappeared.

Saturday, December 9, 2017


I left at 8:16 from Enschede, hoping to arrive at 10:30 in Amsterdam. But half way between Apeldoorn and Amersfoort the train stopped in the middle of nowhere. It was announced that the overhead line had broken ahead of us, and that the train had to return to Apeldoorn. We were adviced to go back to Deventer and travel further over Zwolle. There were some more delays and it was only at 12:52 that I arrived in Amsterdam. It was snowing, but the snow did not stay.

While on the train, I finished reading the book The Seducer's Diary by Søren Kierkegaard, which I started reading on November 18 and bought on December 14, 2013. I found the story to be completely unbelievable, including its form.

In Amsterdam I went to bookshop Scheltema, where at 14:37, I bought the following two books:

  • Vivienne Westwood written by Vivienne Westwood and Ian Kelly in English and published by Picador in 2014, ISBN:9781447254126 for € 9.95.
  • The Waves written by Virginia Woolf in English and published by Random House in 2012, ISBN:9781448138999, for € 5.00.
Next, I went to gallery andriessen & Eyck to see the exhibition Drawing & and more showing drawing by five artist and a work that is not a drawing. Peter Struycken was one of the artists. Besides two drawings, there was also a large wall carpter. Although this day of the exhibition there was no formal opening, but some of the artist, including Peter Struycken and some of their relatives, came to visit. I also met Antonietta Peeters and talked with her about her work.

Friday, December 8, 2017


In the evening, I went by car to Hack42, a hacker space in Arnhem to attend a lecture about the Gigatron. About half way, it started to snow. First a little bit, but it quickly is became stronger and the snow stayed on the road. The traffic had to slow down at some points to below 50 Kmph. I did arrive in time. On the way home, it has stopped snowing and the snow had started to melt, but on the first part on the highway, it seems that the snow had frozen to the road, because the wheels made a lot of noise, not allowing to drive faster than 70 Kmph. At the second half it was possible to drive at a normal speed, but I found most people driving at about 80 Kmph.

The Gigatron is a processor build with 36 TTL chips, an EPROM chip and a 32Kb ram chip. The design was made to include as less as possible chips. This resulted in a 8-bit RISC processor design, which runs at 6.25Mhrz. They managed to make it produce a VGA signal with 64 colours. They also programmed an interpretter for a 16-bits language which processes the program when it is not generating the VGA signal. They showed how it could be used to play the breakout game in colour. Thus improving on the design of Steve Wozniak, with the number of chips needed and the functionality. It should be noted that at that time 32Kb ram chips where not available yet. They plan on making it into a kit with a nice case around it. I am considering to buy one.

Thursday, December 7, 2017


At 17:31:48, I bought the book Observatoria written by Michiel Schwarz in Dutch and published by Westland/Utrecht Hypotheekbank NV Amsterdam in 1980 from charity shop Het Goed for € 0.20.

Wednesday, December 6, 2017


I biked to Enschede Airport Twente to see the arrival of PH-BFR, a Boeing 747-400M, on its last flight, Flight KLM747, in order to be taken apart here in Enschede. The plane landed at 13:05. It is the biggest plane that ever landed at the airport. I found a small map of the last part of the flight, which I guess, is about the part we could see from the airport (except some part when it was behind trees). I took fifteen pictures. Here on the right the one of the touch-down.

Sunday, December 3, 2017

3D piano fractal

Through a tweet by Cliff Pickover, I was directed to website Robert Fathauer: art inspired by mathematics and nature where I found Three-Fold Development, which reminded me about the Fractal Jigsaw that I worked on last year. I thought about remaking this with a 3D printer. Then I noticed the remark that it was based on a 3D model by Henry Segerman. He has written the interesting book Visualizing Mathematics with 3D Printing. A collection of designs can be found on Thingiverse. I did not find the design for the Three-Fold Development. I spend some time figuring out the design myself, making some drawings. I also have been thinking about the different transition methods. I also got the idee to use a 3d printer to make the fractal jigsaw puzzles.


Friday, December 1, 2017


Tuesday, November 28, 2017


This evening, at TkkrLab I wanted to install MINIX3 on my notebook. Some weeks ago, I had made some attempts as well, but those did not work because the MINIX3 does not support USB. I had read somewhere that somebody used KVM to boot an ISO image. However, when I ran pacman, I discovered that my 32-bit Arch Linux installation is no longer supported. When I talked with some member, they noted that probably KVM does not work on my notebook, because most Atom processors do not support Intel® Virtualization Technology. And it appeared mine did not. There is still the option to use QEMU. I decided to at least start with a minimal installation of 64-bit Arch Linux.

Monday, November 27, 2017

Agile software development

There are two ways you can read 'agile software development' depending on how you place the brackets. You can read it is as 'agile (software development)', which is about the software development process, and you can read it as '(agile software) developement', which is about the code and the cost of change. Most people read it in the first manner, and it seems that the second manner is almost forgotten. Even on the eXtreme Programming there is more focus on the process than the software, as refactoring is only first mentioned under the heading 'Courage', while it one of the essential techniques to avoid the exponention growth of cost of change over time. The whole idea of eXtreme Programming was to keep the cost of change down, by avoiding rigidity of the code base, by keeping the code base agile. Without a focus on the agility of the software an agile software development method will fail in the long run. At the start of a new project, it is still easy to produce new functionality and impress a customer with the effectiveness of an agile software development process, but in the long run, it is no guarantee for the maintainability of the software.


Sunday, November 26, 2017


I had the opportunity to visit Utrecht for some hours. I went to bookshop Broese Boekverkopers and arrived there a few minutes before they opened at noon. I was the second customer entering the store. I looked around a little, and at 12:04:14, I bought the book Boud: het verzameld leven van Boudewijn Büch (1948-2002) (a biography about Boudewijn Büch) written by Eva Rovers in Dutch and published by Uitgeverij Prometheus in 2016, ISBN:9789035137424 for € 5.95. I looked around some more and found some interesting book, but decided to have a look at the bookshop Steven Sterk first. I did not buy anything there. I returned to Broese Boekverkopers and at 13:28:19, I bought the book The Philosophy of Andy Warhol: From A to B and Back Again written by Andy Warhol in English and published by Houghton Mifflin Harcourt in 2014, ISBN:9780547543437, for € 8.00. I also bought a Moleskin daily planner for 2018 for € 18.90. At home I discovered that it was the soft cover edition. I have used hard cover edition in the past years.

Thursday, November 23, 2017


Wednesday, November 22, 2017

Booklets and map

At 11:56, I bought the following booklets and map from charity shop Het Goed:
  • black and white and sometimes colourful no2 written by dr. Rebeca Galera de Toro written in English for € 0.95.
  • eigen verzameling zomer 1969 | permanent collection summer 1969 written in Dutch and English and published by Stedelijk Museum Amsterdam in 1969 for € 0.50.
  • Rut Bryk, Catalogusnummer 481 written by Lisa Licitra Ponti in Dutch and English, and published by Stedelijk Museum Amsterdam in 1970 for € 1.50. For € 1.50.
  • Map moderne architectuur in zestien landen van europa by István L. Szénássy. Attachment with Museumjournaal serie 13 no 4, 1968. Size 70 by 85 cm.
  • Omdenken written by Berthold Gunster in Dutch and published by Ja-maar® for € 1.50.


Tuesday, November 21, 2017

HEMA puzzle

Last month, I calculated the number of solutions for the HEMA puzzle, but what I had not taken into accound, was the fact that some of the wooden pieces of the actual puzzle do not fit, simply because the part that should fit in a 'gap' of another piece, is not small enough to fit. I made some analyses of all the possible combinations of pieces that require a physical constraint in all the solutions (using this program) and added that information below. I named the pieces according to the names given by Name that Color. (The name of the pieces is displayed as a tooltip in the displayed solution bellow.) You can indicate which of the pieces do not fit and see which solutions you can actually make. The initial values are for the my instance of the puzzle.

Patina fits Chestnut
Sahara fits Chestnut
Madison fits Chestnut
Victoria fits Chestnut
Amazon fits Chestnut
Arm of Kimberly fits Chestnut
Stem of Kimberly fits Chestnut

Victoria fits Sahara
Amazon fits Sahara
Tabasco fits Sahara
Arm of Kimberly fits Sahara

Arms of Kimberly fit Chestnut and Sahara

Chestnut fits Madison
Patina and Victoria fit Madison
Highland fits Madison
Raw Sienna and arm of Kimberly fit Madison
Victoria and arm of Kimberly fit Madison
Amazon fits Madison

This text is displayed if your browser does not support HTML5 Canvas.


Saturday, November 18, 2017

Open day AKI

In the afternoon, I went to the AKI. Outside I ran into a friend, who in the past studied at the AKI. We decided to attend the open day together. First we went to the media center and library. Outside there was a table where the sold old catalogues for € 5. At 14:04, I bought the following two catalogues: At the photography department we looked inside the dark room, and the friend took a picture of me with the 8x10 camera on photographic paper. We went to dark room again, to see how it was developed. While it was being rinsed, we looked around the students rooms with paintings and other works of art. We did see some promissing work, but because the students were not pressent, it was not possible to talk with them. When the photograph was ready, it was scanned and I received a print (after it inverted). Two teachers were posing and giving assignments. I also made two 'drawings' with a brush and indian ink. I took some pictures of the teachers, especially when they were performing a slow motion dance. At the end we had our picture near the entrance holding a frame with the text: AKI OPEN.

Thursday, November 16, 2017


Monday, November 13, 2017

Bike stolen

At 17:30, I arrived at charity shop Het Goed and looked around the book section. When I came outside around 17:50, my Urban HPV bike, which I got on Wednesday, March 9, 2011, was gone. I spend some time looking around, considering the possibility that I was mistaken about the place wheren I had placed it. I went inside to ask if it happens more often that bikes are stolen in front of the shop. They had only heard about an electric assisted bike being stolen. The bike was already getting old, but at the beginning of the summer the transmission had broken down and was replaced by a new one. I was counting on using it for another three years before it being replaced. I have not much hope of getting the bike back, as usually they are transported to East Europe and sold there. I did report the bike as being stolen when I arrived at home. I will miss all the extra things: The two horns (on a gift from Annabel, the other found in the attic), the three induction lights, and the two yellow CYBER stickers.

Sunday, November 12, 2017

Infinite sequences

I discovered that my statement about street tiling pattern of the first of the month is incorrect. When I increased the length of the sequences to be investigated, I discovered that it did not stop at what I had thought. It seems the list of impossible sequences and chains is infinite. (A chain consists of two sequences that match with valid tiles.) I studied the impossible sequences for a general pattern, but did not discover one. I did noticed that sequences and chains where not really symmetric and realized that this has to do with the encoding method of the street tiles, which all start with an 'A' in the left top corner. This gave me the idea to give eacht street tile its own encoding letters, using the following encoding:
  a bc

  d fg jkl
  e hi mno

    pq ABC
    rs DEF
    tu GHI
This resulted in only a limited set of chains (only with length two) to be impossible. But it seems that there are still infinite impossible sequences. I started visualzing the sequences with embedded JavaScript below and only leaving the characteristic sequences:
This text is displayed if your browser does not support HTML5 Canvas.

It looks that for each length, there are only a limited number of patterns, if we look at the the depth at which the piece extend down. I have selected one pattern for each of them. I also worked on constructing grammar (so far only a regular expression) to match all the patterns.

Friday, November 10, 2017


Thurday, November 9, 2017


Tuesday, November 7, 2017

Bottle ring

This evening at TkkrLab, another member made a bottle ring with the text ffaa5e with the of Blender and one of our 3D printers. The result is show on the top right.

Monday, November 6, 2017


December 2017
November 2017
October 2017
September 2017
August 2017
Alzheimer's Disease
Trip to China 2010
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Califlower fractal


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I, Frans hold the copyrights of this and all other pages on this website. For this website a Creative Commons License is applicable. You may not use this work for commercial purposes. I consider all computer programs to be copyrighted by me under the GNU General Public License, unless stated explicitly otherwise. All quotes (text and program fragments) from other sources are excluded from this, and should be considered as copyrighted by their authors.

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