A cutting apparatus for columnar items such as metal pipes has a base frame that supports a movable cutting blade. Use of the compounds in combinatorial libraries, methods of making the tripodal compounds, sensor devices for detecting carbohydrate targets, and methods of using the tripodal compounds to detect carbohydrate targets in a sample are also disclosed. Buffer times are defined and taken into account during which one machine is able to continue to operate for the duration of the failure of one of the machines of a preceding production step by processing a stock of intermediate products corresponding to the associated buffer time and stored in a buffer during the production. The chromatic dispersion value produced by the Bragg grating filter is thus modified, while its central wavelength remains fixed. The control circuit processes this signal and sequences the transistors to return the extended stroke of the compressor to its maximum stroke.