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The project goal was to design and test a monolithic integrated device for radiation sensing, using optically stimulated luminescence (OSL) from Al2O3:C. The device would consist of GaN/InGaN-based components epitaxially grown on each side of a A12O3:C substrate. Radiation energy stored in the substrate would be stimulated by visible emission from a GaN light-emitting diode (LED) grown on one side of the device, and the OSL emission from the substrate (in the blue region of the spectrum) would be detected by the InGaN pi-n diode grown on the other side of the substrate. The primary application of the device would be in space radiation environments. Thus, two major research thrusts were launched during this project. Firstly, research at Oklahoma State University (Dr. Stephen W.S. McKeever and Dr. E.G. Yukihara) concentrated on characterization of the OSL properties of Al2O3:C in radiation fields typical of those experienced in low-Earth orbit. Secondly, research at the University of Washington (Co-Is, Dr. T.G. Stoebe and Dr. T. Chen) focused of device development and GaN/InGaN epitaxial growth. While progress in each line of research has been substantial, the ultimate goal (that of producing a working prototype device) has not yet been reached. We detail the research progress and identify outstanding issues in this paper.

We describe progress in the development of a close-packed array of bolometers intended for use in photometric applications at millimeter wavelengths from ground- based telescopes. Each bolometer in the may uses a proximity-effect Transition Edge Sensor (TES) sensing element and each will have integrated Normal-Insulator-Superconductor (NIS) refrigerators to cool the bolometer below the ambient bath temperature. The NIS refrigerators and acoustic-phonon-mode-isolated bolometers are fabricated on silicon. The radiation-absorbing element is mechanically suspended by four legs, whose dimensions are used to control and optimize the thermal conductance of the bolometer. Using the technology developed at NIST, we fabricate NIS refrigerators at the base of each of the suspension legs. The NIS refrigerators remove hot electrons by quantum-mechanical tunneling and are expected to cool the biased (approx.10 pW) bolometers to <170 mK while the bolometers are inside a pumped 3He-cooled cryostat operating at approx.280 mK. This significantly lower temperature at the bolometer allows the detectors to approach background-limited performance despite the simple cryogenic system.

The SPEED camera is being developed to study the spectral energy distributions of high redshift galaxies using the Heinrich Hertz Telescope (HHT) in Arizona. SPEED requires a small cryogenic detector array of 2x2 pixels with each pixel having four frequency bands in the 150-350 GHz range. Here we describe the development of the detector array of these high efficiency FSBs. The FSB design provides the multi-pixel multi-spectral band capability required for SPEED in a compact stackable array. The SPEED bolometers will use proximity effect superconducting transition edge sensors as their temperature-sensing element allowing for higher levels of multiplexing in future applications.

Using a comprehensive ionospheric data set comprised of all available ion composition and plasma temperature measurements from satellites, the vertical distributions of ion composition and plasma temperatures are defined from middle latitudes up into the polar cap for summer conditions for altitudes below about 1200 km. These data are sufficient to allow a numerical estimation of the latitudinal variation of the light ion outflows from within the plasmasphere to the polar wind regions. The altitude at which significant light ion outflow begins is found to be lower during solar minimum conditions than during solar maximum. The H(+) outward speeds are of the order of 1 km/s near 1100 km during solar maximum but attain several km/s speeds for solar minimum. He(+) shows a similar altitude development of flow but attains polar cap speeds much less than 1 km/s at altitudes below 1100 km, particularly under solar maximum conditions. Outward flows are also found in the topside F-region for noontime magnetic flux tubes within the plasmasphere.

The atmospheric spectral energetics studies performed before the First GARP Global Experiment (FGGE) were reviewed, and the deficiencies of these studies were pointed out. The data generated by the FGGE IIIb analyses of the European Center for Medium Range Weather Forecasts, the Geophysical Fluid Dynamics Laboratory, and the Goddard Laboratory for Atmospheric Sciences over the entire globe during the FGGE summer and winter are used to analyze the atmospheric spectral energetics. Comparisons were made between the results using three FGGE IIIb analyses, and between previous and current studies with the spectral energetics of the Southern Hemisphere.

The objective is to examine the maintenance of momentum and thermal fields in the Southern Hemisphere and the diabatic heating and generation of available potential energy of the entire global atmosphere. The data generated by the Goddard Laboratory for Atmospheric Sciences First GARP Global Experiment (FGGE) III-b analysis for SOP1 and SOP2 are used for this effort. It is observed that the atmospheric circulation of the Southern Hemisphere exhibits a double jet structure (subtropical jet and polar jet) in winter and a single jet in summer during the FGGE year. The geographic distribution of standard deviation in the height field at 500 mb indicates that the major eddy activities occur in the downstream side of the polar jet and poleward side of the subtropic jet in winter. However, the major eddy activites go hand-in-hand with the jet stream in summer. The momentum transport is essentially carried out by the transient eddies in both seasons. The distribution of the temperature field is more axisymmetric in the Southern Hemisphere than in the Northern Hemisphere. The sensible heat is mainly transported poleward by transient eddies along the strong baroclinic zone where the jet streams are located. In other seasons, it is shown from the geographic distribution of the divergence of transient eddy sensible heat flux that the Antarctic continent acts as a heat sink to consume the sensible heat converged toward the polar area from the middle and low latitudes.

The history data of winter simulation by the GLAS climate model and the NCAR community climate model are used to examine the generation of atmospheric kinetic energy. The contrast between the geographic distributions of the generation of kinetic energy and divergence of kinetic energy flux shows that kinetic energy is generated in the upstream side of jets, transported to the downstream side and destroyed there. The contributions from the time-mean and transient modes to the counterbalance between generation of kinetic energy and divergence of kinetic energy flux are also investigated. It is observed that the kinetic energy generated by the time-mean mode is essentially redistributed by the time-mean flow, while that generated by the transient flow is mainly responsible for the maintenance of the kinetic energy of the entire atmospheric flow.

A synoptic and spectral analysis of a blocking event is presented, with attention given to the temporal evolution, maintenance, and decay of the block. The GLAS numerical climate model was used to generate a blocking event by the introduction of SST anomalies. Wavenumbers 2 and 3 became stationary around their climatological locations, and their constructive interference produced persistent blocking ridges over the west coast of North America and the other over western Europe. Time variations of the kinetic and potential energies and energy conversions during the blocking were performed. Spectrally filtered Hovmoller diagrams were developed for the winter of 1976-77, and showed that long waves were stationary over most of the interval, which featured severe weather conditions.

The spectral energetics of two blocking case studies from the winter of 1978-79 are calculated. One case occurred over the North Atlantic and the other over the North Pacific. The temporal evolution and geographical distribution of the energetics of the planetary-scale (zonal harmonic wavenumbers 1-4) and the intermediate-scale (wavenumbers 5-10) wave ensembles are examined to identify the physical mechanisms important in the blocking process. The Atlantic block was forced by the nonlinear interaction of intense baroclinic cyclone-scale waves with barotropic, ultralong waves. The Pacific blocking resulted from the baroclinic amplification of planetary-scale waves. In addition, at least two necessary conditions are required for the development of blocking. First, one of the forcing mechanisms must be in operation, and second, the phase of the antecedent planetary-scale waves must be such that the forcing mechanism can amplify them into a blocking pattern. In each of the cases studied, the blocking developed downstream of intense intermediate- or large-scale cyclogenesis.

The contributions of standing (time-mean) and transient (time-departure) waves to the atmospheric spectral energetics are analyzed using the NMC (National Meteorological Center) data of winter 1976-1977. It is found that the standing long waves are responsible for the major horizontal sensible heat transport and also for the significant horizontal momentum transport. Furthermore, the major contents of eddy available energy and eddy kinetic energy of standing waves are in the long-wave regime. However, the spectral energetics analysis indicates that the standing long waves are energetically less efficient than the transient long and short waves. It is suggested that the lower efficiency of the standing long waves in the atmospheric energetics may be one of the physical factors causing the underforecast of the standing long waves in the numerical weather prediction models.

The winter simulations of the GLAS climate model and the NCAR community climate model are used to examine the maintenance of the atmospheric kinetic energy. It is found that the kinetic energy is generated in the lower latitudes south of the maximum westerlies, transported northward and then, destroyed in the midlatitudes north of the maximum westerlies. Therefore, the atmospheric kinetic energy is maintained by the counterbalance between the divergence (convergence) of kinetic energy flux and generation (destruction) of kinetic energy in lower (middle) latitudes.

In January 1977, a warming of the polar troposphere occurred following a major stratospheric warming. The temperature increase in the polar troposphere is found to be larger below 400 mb than in the upper troposphere. Analysis of the heat budget of the polar troposphere shows that the eddy heat flux convergence is the major factor responsible for the tropospheric warming.

The space-time Fourier spectral analysis and the equations of kinetic energy and momentum transport in the wavenumber-frequency domain proposed by Kao (1968) and modified by Kao and Lee (1977) using Tukey's (1967) numerical spectral analysis are employed to analyze the 200 mb wind fields of a four-month climate experiment of the GLAS atmospheric circulation model. This climate run covers the period from Jan. 1 to Apr. 30, 1975. The current study analyzes a 90-day (Jan. 15-Apr. 14, 1975) wind field of this climate run. A comparison is conducted between the current study and observations reported by Kao and Lee. It is found that the 200 mb latitudinal distributions of model mean zonal wind, zonal and meridional kinetic energy and momentum transport of eddies agree fairly well with the observations.

Wavenumber frequency spectral analysis of a 90 day winter (Jan. 15 - April 14) wind field simulated by a climate experiment of the GLAS atmospheric circulation model is made using the space time Fourier analysis which is modified with Tukey's numerical spectral analysis. Computations are also made to examine how the model wave disturbances in the wavenumber frequency domain are maintained by nonlinear interactions. Results are compared with observation. It is found that equatorial easterlies do not show up in this climate experiment at 200 mb. The zonal kinetic energy and momentum transport of stationary waves are too small in the model's Northern Hemisphere. The wavenumber and frequency spectra of the model are generally in good agreement with observation. However, some distinct features of the model's spectra are revealed. The wavenumber spectra of kinetic energy show that the eastward moving waves of low wavenumbers have stronger zonal motion while the eastward moving waves of intermediate wavenumbers have larger meridional motion compared with observation. Furthermore, the eastward moving waves show a band of large spectral value in the medium frequency regime.

Nimbus 5 satellite radiances for the period 1973-74 are used to examine the seasonal variation of available potential energy in the stratosphere in order to provide a further observational basis for a long-term numerical simulation of stratospheric circulation. The maximum value of stratospheric zonal available potential energy, A(Z), in the upper and middle stratosphere shows pronounced variations between winter and summer, while little variation occurs in the lower stratospheric A(Z). The aperiodic occurrence of sudden warmings complicates the seasonal variation of A(Z) and A(E) (eddy available potential energy) in the stratosphere, making the energetics irregular. Time-Fourier analysis reveals that the primary variation of A(Z) and A(E) in the stratosphere is annual and semiannual, respectively.

In order to simulate the seasonal variation of the stratospheric circulation in a zonal mean circulation model, a Newtonian heating function and a detailed heating function were applied to the troposphere and stratosphere, respectively. The purpose of this study was to investigate the response of stratospheric circulation to alterations of the radiative equilibrium temperature of the troposphere.

Diagnostic computations of nonlinear cascades of enstrophy have been performed in the wavenumber domain for two northern summers. Attention is focused on the interactions among the waves, the interaction between the zonal flow and a given wave and the exchanges due to the beta effect. It is found that two wave ranges (low and intermediate wavenumbers) cascade enstrophy to two ranges of wavenumbers. Calculations are also performed to evaluate the contribution from the standing (92-day mean) and transient modes to the nonlinear enstrophy cascade.

Energetic analyses of the NMC initial conditions and NMC six-layer primitive equation operational prediction model 12-hr forecast for a developing cyclone are presented. Consideration is given to the total kinetic energy, the energetics of the divergent and nondivergent flows and the baroclinic (vertical shear flow) and barotropic (vertical mean flow) components of the kinetic energy. It is found that the model initial conditions lose 10-15% of the kinetic energy at various levels compared to a limited-area multivariate statistical analysis of the observational data, leading to a decrease in the horizontal kinetic energy flux, a misrepresentation of the synoptic scale wave system in the 12-hr forecast. Similar results are obtained for the nondivergent flow, while the divergent flow energetics are not reproduced accurately by the model. The horizontal flux terms of the vertical mean and vertical shear energetics are also not found to be reproduced in the upper levels, although horizontal flux contributions to the baroclinic component are improved at middle and lower levels. Finally, vertical shear kinetic energy generation is found to be well represented in the model prediction, however kinetic energy conversion between vertical shear and mean flow is not reproduced in the lower layer.

The magnitude of the divergent component of the wind is relatively small compared to that of the nondivergent component in large-scale atmospheric flows; nevertheless, it plays an important role in the case of explosive cyclogenesis examined here. The kinetic energy budget for the life cycle of an intense, developing cyclone over North America is calculated. The principal kinetic energy source is the net horizontal transport across the boundaries of the region enclosing the cyclone. By investigating the relative importance of the divergent and nondivergent wind components in the kinetic energy budget, it was found, as expected, that neglecting the divergent wind component in calculating the magnitude of the kinetic energy is of little consequence, but that the horizontal flux convergence and generation of kinetic energy depend crucially upon the divergent component. Modification of the divergent wind component can result in significant changes in the kinetic energy budget of the synoptic system.

The paper analyzes the energetics involved in the two numerical experiments described in Part I, concerning a longwave radiative transfer model and a simple Newtonian cooling (or heating) model. A three-dimensional quasi-geostrophic model is developed and used over the entire annual cycle to test the climatic responses of the stratospheric circulation to the cited two different longwave radiative heating models. It is shown that the eddy energy parameters (eddy kinetic energy, eddy available potential energy, generation of the latter, and vertical propagation of eddy geopotential energy) undergo annual variations with maximum values in winter and minimum values in summer. The zonal energy parameters exhibit semiannual variations with major maximum values in winter, minor maxima in summer and minima in spring and fall. Analysis of the energy cycle reveals that the vertical propagation of eddy geopotential energy and the generation of eddy available potential energy are the energy sources for energetics in the upper stratosphere. Ways in which the longwave radiative processes may affect the stratospheric energetics are identified.

The architecture tradeoff issue is discussed, concentrating on an oversimplified version of the multiprocessing aspect. A degree of symmetric multiprocessing is unavoidable; the choice is either complete symmetric multiprocessing or a number of identical pipelines. The processing elements can be geared to do either plane-multiprocessing, or line-multiprocessing. Other important design choices are the number notation, word length, main memory size, cache memory size, and different means to implement data transport.

Passive damping method for aligning instantaneous spin, symmetry, and angular momentum axes of solid axisymmetric almost spherical satellite gyroscope