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Ben : "Put the meter on resistance measurement, put the FLED in a dark
environment, and measure the resistance. Do this for all your FLEDs."

That's how I measure the resistance and balance the left and right eyes
by using the same resistance Fleds. 

Poke two holes, just big enough for the leads to pass through. Insert
the Fled onto the cap and put the cap back onto the film canister. Measure
the resistance of the fleds and group them together with same/very close
resistance.

In many ways, both the 74*240
and 74*245 are equally handy
for BEAM use; both have 20 pins, and so the main difference
that most folks will care about is that one inverts drive
inputs, while the other doesn't. Out of curiousity, I
decided to torture test the two chips to see how they
compared under load.

所以你說我們的「母國市場」是什麼？我們的母國市場就是整

個世界

北歐人認為小國要搶市場，要有速度，就必

須靠創新，而創新就來自研發

To the advantage of these bacteria, they are able to detect both attractant and repellant chemicals (6). When an increasing concentration of an attractant (sugar) or decreasing concentration of a repellant (fatty acid) is detected, the bacteria will decrease the frequency at which it tumbles and will thus swim for longer periods (5). This gives the bacteria more of an opportunity to swim into an area where the concentration of a needed chemical is high and away from areas which contain toxic chemicals. Conversely, detection of decreasing concentrations of attractants or increasing concentrations of repellants causes bacteria to increase their tumbling frequencies (5). While the tumbling remains random, increasing the amount of tumbling allows bacteria to change direction more often, hopefully oriented away from a repellant and toward an attractant gradient. What must be understood here is that the movement of these bacteria is still random just as it would be in a solution where there was no detection of chemical gradients; however, the bacteria modify their movement patterns by increasing and decreasing the frequency at which they change from swimming to tumbling.

motile bacteria move via rotation of one or more flagella, turning counter-clockwise when swimming and clockwise when tumbling

当一只阿米巴虫向右转弯后，下一次向左转的可能是向右转的2倍，反之亦然

转弯时，阿米巴虫向预方向伸展部分“躯体”，在细胞的同侧产生了一道蛋白痕，这道痕使细胞临时性更倾向于向相反方向运动，这种机制使阿米巴虫来避免了圆周运动，“周游”的领域更广阔。

variable delay

We assume that the slowly changing waveform at the
Nv
input produces a single output transition when it crosses
the Nv
switching threshold. This is accomplished by using a 74HC14
or similar CMOS Schmitt
trigger. When 74HC04 or 74HC240s are used for Nv
inverters some nasty oscillations occur during switching
which makes these inverters unsuitable for most Nv
networks greater than 2 Nv
in series.