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Journal Journal: Kapla: Spirals

Just building stuff, sometimes continuing the following week: Week 1 Week 2

The booklet had a spiral which took some time to figure out. Basically, 2 pieces in the middle, and 1 on each side of it, which makes it look really cool, and more importantly, supports the turned pieces. They do a slow turn though.

Comment Interpretting instead of compiling (Score 2) 674

I once discovered that an interpretting parser was faster than a compiled version of it. Probably because the compiled version became so large that it was larger than the CPU caches, causing lots of reads from memory, while the interpretter did not. It is often the case that interpretting is fast enough and that there is no need for compiling (to machine code or virtual machine).

Comment Re:wireless sensor network (Score 1) 67

The LoRa network has some measurements against these kind of attacks. I built a LoRa node myself (to connect to the free network owned by with only limited coverage, see and had to generate two private/public keys, one for the wireless connection and one for the application, meaning that the transmitted information is encrypted. There is also frame counting implemented. The maximum rate on this free network is limited to about 80 bytes per hour. Maybe the commercial network has a slightly higher rate and is bi-directional. The railway station of Utrecht has connections in five directions and is know to cause massive delays in the very tightly scedule rail network in the Nethelands due to (for example) frozen rail switches. So, I guess they are only using it to signal these kind of things. Not something as vital as the position of the switch.

Comment Self taught (Score 1) 515

I learned Algol 60, FORTRAN, and Lisp while still in high school. Writing programs out on paper before traveling to a near by city by train to make punch cards and run the programs, often going home with s stack of listings to study the results. Only in second year of university did I learn something truely new: currying and lazy evaluation. More details.

Comment Re:It time, this will be good for Lee Sedol (Score 1) 111

I felt that both the commentaries on the official stream and the one of AYA with Kim Myungwan were mostly focusing on analysing alternatives to moves that were already played, instead of focusing on possible moves to be played. At one point Haijin Lee, also known as Haylee, the current secretary of the International Go Federation, took a seat behind the computer. While Lee Sedol was taking a long time to think about the 78 move, she suggested the "wedge" move to Kim Myungwan. He first asked with some surpise: "This one?", and after she confirmed he exclaimed: "O, that is very creative". They analyzed the various possibilities to take benefit of the move, but did not see how it could work. Haijin at one time remarked, "It has to work", indeed because otherwise the game would be a loss. Then with still 6:16 on the clock, Lee Sedol played the proposed "wedge" move at L11. Then Haylee has to go. Then AlphaGo plays the move that Kim Myungwan just played as a possible continuation. Soon it is acknowledged that it is a mistake and that the chances for Lee Sedol have turned. The "wedge" move is later recognized as the genius move with which Lee Sedol defeats AlphaGo. Demis Hassabis tweeted Mistake was on move 79, but #AlphaGo only came to that realisation on around move 87 and When I say 'thought' and 'realisation' I just mean the output of #AlphaGo value net. It was around 70% at move 79 and then dived on move 87. The question remains if there is another move that AlphaGo could have played to prevent Lee Sedol from winning. If this is not the case, then move 78 is simply an over play that tricked AlphaGo.

It seems that AlphaGo suffers from the horizon effect, meaning that when it is ahead, it becomes blind for wining sequence that starts with an unusual move. It is great that Lee Sedol has won this game, because it shows that humans still have a better understanding of the game. Relying on a mental vocabular for reasoning about the game, has some weaknesses, it might still prove superior when reasoning about very complex situations like the one encountered in this game. It seems that Lee Sedol took most time to think about this move. Later on in the game, AlphaGo, played some bad moves, probably because its winning percentage had dropped.

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Journal Journal: Chronicle: Got my Raspberry Pi 3

So, i got a Raspberry Pi 3, and it arrive the day after Pi Day. But, as i purchased it from the UK, and they don't have a Pi Day, it's somewhat understandable. My Ukranian coworker asked me about P-day, and in the ensuing discussion she explained that in Russian it is pronounced pea.

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Journal Journal: TBD: Posted

The test was responded to, an i tried my hand at writing a JE for it. I quickly came up with something on my mind, and twisted it for the comment below, keeping it short.

Nothing was quoted, so the post had to include whatever material was being comment on, as opposed to specific quotes. Nonetheless, it's a creative effort that could be fun and challenged, if taken seriously (within reason). I'd like to see other people try it.

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