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.
Hail, snow and rainAround 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.
Snow and rainIn 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.
AmsterdamI 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:
GigatronIn 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.
BookAt 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.
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.
3D piano fractalThrough 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
MINIX3This 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.
Agile software developmentThere 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.
BroeseI 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
Booklets and mapAt 11:56, I bought the following booklets and map from charity shop Het Goed:
HEMA puzzleLast 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.
Open day AKIIn 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:
Thursday, November 16, 2017
Bike stolenAt 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.
Infinite sequencesI 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:
Friday, November 10, 2017
Thurday, November 9, 2017
Bottle ringThis 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.
Trip to China 2010
-- contact -- Frans
My life as a hacker
The Art of Programming
HTML to LaTeX
eXtreme Programming Programs Hamilton cycles