We present the design and implementation of a very compact adaptive optic system that senses the return light from a sodium guide-star and controls a deformable mirror and a pointing mirror to compensate atmospheric perturbations in the wavefront. The deformable mirror has 19 electrostrictive actuators and triangular subapertures. The wavefront sensor is a Hartmann sensor with lenslets on triangular centers. The high-bandwidth steering mirror assembly incorporates an analog controller that samples the tilt with an avalanche photodiode quad cell. An {line_integral}/25 imaging leg focuses the light into a science camera that can either obtain long-exposure images or speckle data. In laboratory tests overall Strehl ratios were improved by a factor of 3 when a mylar sheet was used as an aberrator. The crossover frequency at unity gain is 30 Hz.

This manual is intended primarily for use as a reference by analysts applying the WORLD model to regional studies. It also provides overview information on WORLD features of potential interest to managers and analysts. Broadly, the manual covers WORLD model features in progressively increasing detail. Section 2 provides an overview of the WORLD model, how it has evolved, what its design goals are, what it produces, and where it can be taken with further enhancements. Section 3 reviews model management covering data sources, managing over-optimization, calibration and seasonality, check-points for case construction and common errors. Section 4 describes in detail the WORLD system, including: data and program systems in overview; details of mainframe and PC program control and files;model generation, size management, debugging and error analysis; use with different optimizers; and reporting and results analysis. Section 5 provides a detailed description of every WORLD model data table, covering model controls, case and technology data. Section 6 goes into the details of WORLD matrix structure. It provides an overview, describes how regional definitions are controlled and defines the naming conventions for-all model rows, columns, right-hand sides, and bounds. It also includes a discussion of the formulation of product blending and specifications …

The authors search for coherent Bremsstrahlung radiation was unsuccessful but during those measurement attempts, they made the first observation of coherent Cherenkov radiation in a solid. (Previous measurements had all been made in gases.) Because of the large index of refraction in solids, Cherenkov radiation is emitted at a large angle with respect to the electron beam while transition radiation is not. The result is that both components of the coherent spectrum can be examined at the same time. While the authors have already shown that coherent transition radiation provides spectral information on the longitudinal form factor of the bunch, the Cherenkov radiation produces spectral information related to the transverse form factor. Complete testing of the prototype grid interferometer has led to a final design for the large aperture low frequency interferometer. Different high sensitivity detectors have been examined. For the highest sensitivity work the cooled Si bolometer detector provides the best match to the interferometer optics. They also propose to test a wideband room temperature integrated receiver in an attempt to examine single bunches with the interferometric technique. The authors have also found that a time resolved approach to the analysis of single bunches can be carried out if …

The purpose of this project is to calculate the contribution of field line diffusion to particle diffusion in the stochastic magnetic field at the tokamak edge. The author uses the approach of quasi magnetic surfaces. If the magnetic field line makes sufficiently large number of toroidal transits before suffering large radial excursion, then the method of quasi magnetic surface is valid for this problem. This method has three components: determination of particle drift trajectories, a model for magnetic field configuration, and determination of field line diffusion.

As overall US Advisor for ISO/TC-85, SC-5, Dr. Westfall met with (1) Work Group 1, ``Measurement Techniques for the Chemical and Physical Characterization of UF{sub 6}, UO{sub 2}, and Mixed Oxide,`` on Monday, March 21, (2) Work Group 5, ``Standardization of Measurement Methods for the Characterization of Solid and Solidified Waste Forms, and for the Corrosion of their Primary Containers,`` on Tuesday, March 22; and (3) the full Subcommittee-5 on Wednesday, March 23. The status of work by all seven work groups in SC-5 was reported. Those having to do with nuclear fuel transportation (WG-4: UF, Containers, WG-9: Cask Trunnions, and WG-10: Cask Confinement) either have approved standards or drafts at an advanced stage of development. These work group convenors were asked to maintain their membership and establish new work areas in the field of nuclear fuel packaging. Definition of scope for new work is to be done in coordination with the interested staff members of the International Atomic Energy Agency, Vienna, Austria. On Thursday, March 24, the Cogema-Marcoule Plant staff hosted the SC-5 members to technical tours of their nuclear fuel reprocessing and waste vitrification and storage facilities.

Due to the increasing demand for higher operating frequency, lower attenuation, and stronger piezoelectricity, use of the layered structure has become necessary. Theoretical studies are carried out for ultrasonic waves propagating in the multilayered piezoelectric substrates. Each layer processes up to as low as monoclinic symmetry with various thickness and orientation. A plane acoustic wave is assumed to be incident, at varied frequency and incidence angle, from a fluid upon a multilayered substrate. Simple analytical expressions for the reflection and transmission coefficients are derived from which all propagation characteristics are identified. Such expressions contain, as a by-product, the secular equation for the propagation of free harmonic waves on the multilayered piezoelectric substrates. Solutions are obtained for the individual layers which relate the field variables at the upper layer surfaces. The response of the total system proceeds by satisfying appropriate interfacial conditions across the layers. Based on the boundary conditions, two cases, {open_quotes}shorted{close_quotes} and {open_quotes}free{close_quotes}, are derived from which a so-called piezoelectric coupling factor is calculated to show the piezoelectric efficiency. Our results are rather general and show that the phase velocity is a function of frequency, layer thickness, and orientation.