Propagation of super-Gaussian field distributions

The near- and far-field propagation of initially super-Gaussian field distributions is discussed. upon propagation, the beam profile is shown to undergo distortions of a magnitude which increases with the super-Gaussian order. These distortions can lead to a significant increase of the on-axis intensity in the near-field. The beam quality, evaluated both in terms of the beam parameter product and theM ² factor, is shown to decrease as the super-Gaussian order gets larger. These calculations also illustrate the difficulties associated with theM ² factor when characterizing the propagation of a beam with increasingly sharp edges. The effect of the transmission of the super-Gaussian field through a super-Gaussian graded-reflectivity mirror (GRM) is also discussed. The results of this study have direct implication in the domain of GRM resonator design.     

The Finite Horizon Trended Inventory Replenishment Problem With Shortages

A new type of replenishment policy is suggested for an inventory item having a finite shortage cost and linear trend in demand over a finite time horizon. The optimal solution of the suggested replenishment policy has a lower total cost as compared with the optimal solution for the traditional replenishment policies.     

A hybrid approach to discrete mathematical programming

The dynamic programming and branch-and-bound approaches are combined to produce a hybrid algorithm for separable discrete mathematical programs. Linear programming is used in a novel way to compute bounds. Every simplex pivot permits a bounding test to be made on every active node in the search tree. Computational experience is reported.     

Temperature program optimization by computer simulation for the capillary GC analysis of fatty acid methyl esters on biscyanopropyl siloxane phases

The selectivity of capillary columns coated with biscyanopropyl siloxane stationary phases for the separation of fatty acid methyl esters has been optimized by means of computer-assisted column temperature optimization software. Temperature programming rates yielding the highest resolution in the shortest analysis time were selected for split, splitless, and on-column injection operated in the constant pressure and pressure programmed modes.     

A study of a coadsorbate surface diffusion (Pb on C/W)

The influence of a coadsorbed submonolayer (carbon) on the diffusion of adatoms (lead) along a crystal surface (tungsten) is studied in a preliminary manner by a field electron microscope technique. Experiments show that the surface diffusion of lead is strongly affected by the coadsorption of carbon: (1) The diffusion of Pb which is easy around (110) and (111) and difficult around (100) on clean tungsten becomes easier around (100) than around (110) and (111). (2) The diffusion anisotropy on the stepped surface around (100) is changed by carbon adsorption. (3) C adatoms enhance the diffusion of Pb especially around (100). (4) The mean carbon coverage required to observe these effects is only a few hundredths of a monolayer. The dependence of the surface diffusion on such small impurity coverages is discussed.