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Londoncentric world map

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  Some people think that the world map centred on Greenwich is an unnecessary layover from the times of empire. Of Course, many countries issue maps with themselves more central. Living in London, with the nassim I have for home I felt that the longitude being centred in Greenwich wasn’t enough. I thought that the latitude should also be centred in Greenwich. The majority of world maps use what is called the Mercator projection. This is a projection based on putting the sphere of the world inside a cylinder. The position of a location on the globe projected onto this cylinder is then where it occurs on the map. This has the nuance of distorting the polls and making areas closer to the poles much larger than they actually are. There have been many attempts to change the projection using other techniques that push the distortions to different places. There are maps that attempt to keep the relative surface area of countries accurate to life. The nature of creating a flat representati...
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Syrup in the vains

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This is something I thought about for the first time this week (Back in October). It should be a simple calculation. Amount of blood times blood sugar level. A normal blood sugar level when fasting (Including after just waking up) is 72 to 99mg/dL. A normal blood sugar level 2 hours after eating would be below 140mg/dL. The amount of blood in the body normally accounts for around 10% of the body weight .  Given that blood is mainly water its density won’t be far off that of water so it stands to reason that the average 70kg human will have about 7 litres of blood. Multiplying through this gives a waking total blood sugar of 5g and an after lunch blood sugar of 10g. Since this is the body’s preferred source of energy, it would be interesting to know how long the body can survive on just the sugar in the blood. Sugar is about 375 cal/ 100g That means that we have 38 calories of sugar in our blood after lunch and 19 after fasting. Assuming a 2000 cal daily energy use the body require...
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Structural engineering with cardboard

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Moving into a new flat I have ended up with a lot of cardboard and have actually struggled to get it to all be taken away. I then saw this Kickstarter on hacker news which introduced me to the idea that I could perhaps use the cardboard I had been throwing away the whole time. I have been toying with some ideas for building myself a robot, or at least a robot arm but they seem to be just ludicrously expensive and still not able to lift much weight. One of the problems with the advancement of robotics is that although processing power has come down in price at a rate that no other product ever has, the cost of actuators (The motion inducing components like motors) has remained largely the same. I want to explore an idea I have for using cheaper motors in a robotic arm in another post though. The problem I want to look at here is the possibility of being able to use cardboard, a material which can almost be considered to have a negative price, as the structure to the robot. I love the ...
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The twelve fold way

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I really struggle to remember the combinatorial rules. Do I need to use choose or do I need to use permute? How do I calculate each of them? Is this a case of stars and bars or is this something else? One of the things I want to add to my chatbot program is a way to ask which of the many systems should I be using? I did once try to build a javascript tool although I don’t think it ever really made itself into a useful state. I recently found a paper called “The twelvefold way” which explains all the different ways you put balls in boxes (or urns as is used in the paper). It really helped me to understand, at least a little better, how to calculate the different permutations of the problem. With this newfound understanding, I once again had a go at producing a program to calculate each, with a simple form-based input. One of the things that I wanted to extend this to doing was informing me of what the calculation method was. I really like the way google now lends a hand when you a...
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