<P> Recent developments have mirrored those in the private sector logistics, with an increasing scientific and quantitative emphasis and reliance on networked computing power . </P> <P> Originally, staff officers were distinguished from line officers only by the details of their uniforms, such as number of buttons on lapels, cuffs and pockets, epaulets, color, cut of coat, or amount of gold lace . </P> <P> Uniform regulations issued 1 May 1830 specified that a Purser should have, in addition to the live oak leaf and acorn (which appeared on the collars of all officers in varying abundance) a cornucopia embroidered on the collar of his full dress coat . In 1841 the distinguishing mark on the Purser's collar was changed to a 4" row of gold embroidered oak leaves and acorns . </P> <P> A modification of the uniform regulations, dated 27 May 1847, provided gold epaulets for the Purser on which was a solid crescent with the Old English letters "P.D." in silver within the crescent . In September 1852 the letters "P.D." were abolished . </P>

What does a supply officer do in the navy