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Full Version: Refugee camps of tomorrow + Aquatic microbots + How should you mark your diodes?
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Cities of Tomorrow: Refugee Camps Require Longer-Term Thinking
http://weburbanist.com/2015/12/01/cities...-thinking/

EXCERPT: Former mayor of the world’s second-largest refugee camp, humanitarian Kilian Kleinschmidt notes that the average life of a refugee camp is 17 years, “a generation,” and these places need to be recognized as what they are: “cities of tomorrow,” not the temporary spaces we like to imagine....



Returning to the Sea with 3D-Printed Fish
http://machinedesign.com/materials/retur...inted-fish

EXCERPT: [...] By combining 3D-printing and micro-robotics technologies, a team lead by Shaochen Chen and Joseph Wang came up with complex geometries no wider than the width of a human hair (about 0.004 in.). Chen is able to print hundreds of these micro-robots in seconds. Each fish-shaped swimming machine, which measures 120 microns long and 30 microns thick, is 3D printed on a process developed in Chen’s lab called microscale continuous optical printing. [...] Platinum added into the tail propels the fish as it reacts with hydrogen peroxide. [...] These swimming machines could be used to clean toxins from liquids. In an experiment, the fish bonded with the toxins, and fluoresced in a red glow. Co-author Jinxing Li said, “Another exciting possibility we could explore is to encapsulate medicines inside the microfish and use them for directed drug delivery....”



How should you mark your diodes?
http://blog.screamingcircuits.com/2015/1...iodes.html

EXCERPT: [...] We don't know what you had in mind, and, we don't have the schematic. If you use the practice of marking diodes with a (+) on the anode, we don't have any more information than if you didn't mark it at all. The same holds for using a minus (-) sign. It really doesn't give us any information. [...] So how should you mark your diodes....
Indeed, marking a diode with plus or minus symbols seems confusing.  The better way is to remember that electrons flow from the cathode to the anode.  We can also imagine positive current (the holes left behind moving electrons) moving from the anode to cathode.