Stringing Along

The autosampler system is controlled by an IBM computer system, as is the series of pumps for the cell and the sample wash pot. An Archer single board computer (Sherwood Data System) programmed via ASCII strings along an RS232 interface, controls the pumps and the autosampler, setting up a stable representative sample which is then measured by using the standard Solomat software and hardware. 

A balance can be used to measure weights. Make a balance like the one shown. Tie a paper bag to each end of a meter stick. Tie another string in the middle of the meter stick and have a friend hold the string. Move the string along the stick until you get the bags balanced at the same height from the floor. 

Mark the string along the southern boundary with paint at the sampling points. 

We want to learn how to quantize the radiation field. As a first step, consider a continuous elastic system. Any classical continuous elastic system in one dimension can be treated by a normal-mode analysis. Consider an elastic string of length a [m], tied at both ends to some fixed objects, with density per unit length p [kg m ], and tension, or Hooke s law force constant kH [N m-1]. The transverse displacements of the string along the x axis can be described by a transverse stretch y(x, t) at any point x along the string and at a time t. One can describe the y(x, t) as a Fourier sine series in x ... 

For the diagram from Example 15.9(1), we see that pb is the canonical projection of the homotopy colimit to whereas p/ is the quotient map that collapses each string along the attached cylinder to a point. 

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