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Source Sampling
Published in Howard E. Hesketh, Air And Waste Management, 2019
Rinse the container with two or three 25 ml portions of acetone, cap the container and shake, then transfer into the graduated cylinder to rinse it, and then put the rinse through the funnel into a beaker; thus, the container, the graduated cylinder and the funnel have been rinsed.
Estimating soil texture with laser-guided Bouyoucos
Published in Automatika, 2020
In Figure 5, only the first 15 min of the signals are shown, so that the first 40 s looks better. According to the figure, almost no change has been observed at the top-most sensor (#5) up to 400th sampling (approx. 200 s). In the Bouyoucos analysis, however, the sand percentage can be determined by measuring only the first 40 s. This can be interpreted as that the laser light in the LGB system is blocked by small particles suspended in water and therefore did not reach to the LDR sensors, even at the top-most level of the beaker, for a long time (200 s). Nevertheless, this result shows that the estimation of the amount of sand can be possible by evaluating the whole of the signal. The data preparation process of the LGB is given below in an algorithmic manner. Put the empty beaker in its place, and switch all lasers and LDR sensors on, check the light intensity values read by all LDRs. If they are not equivalent with a very small tolerance to each other, normalize it.Put the prepared soil and distilled water solution into the beaker, and fill the beaker up to 1000 ml line with distilled water and stir it adequately.Start the electronic system, and store the values measured at 2 Hz for 90 min by LDR sensors on the computer. At the end of each experiment, a dataset with 5 rows (one for each sensor) and 10,800 columns (2 Hz × 90 min × 60 s) is obtained.Drain and clean the beaker after each experiment. Make two repetitions for each experiment of each soil sample.If there is an untried soil sample, go to step 1 for this sample.As a result, a dataset with 60 rows and 10,800 columns is generated.