Multifacet holographic optical elements

New types of holographic optical elements, combining the flexibility of computer generated holograms with the large space bandwidth product and high diffraction efficiency of interferometrically recorded volume phase holograms, are demonstrated. The optical elements are recorded by subdividing a volume hologram film surface into numerous small areas (facets), each of which is individually exposed under computer control. Each facet is used to produce a portion of the desired final wavefront. Three different optical elements are demonstrated

The Consummation of the Exodus: A Study of the Exodus Motif in the Revelation

The study of the Exodus motif grew out of the author\u27s curiosity concerning the clear reference to the Exodus in Revelation 15:3. The question which arose concerned the extent to which the Exodus motif is used in the Apocalypse, and its significance. Therefore, the purpose o this study is to examine and demonstrate the use of the Exodus motif in the Revelation. The study will commence with a discussion in chapter one of typology and the unity of Scripture. Because the Exodus is a major source of Old Testament types, an attempt will be made in chapter one to illustrate the importance and use of the Exodus motif throughout Scripture. Next, several of the most comprehensive examples of the Exodus motif in the Revelation will be presented. Chapter two will be a consideration of how Yahweh dwelt with His people in the tabernacle, and how this idea is used in the Apocalypse. Included in this chapter will be a discussion of the glory of God as used in the Revelation, and its relation to the shekinah of the Old Testament tabernacle. The concept of holy war will be examined in chapter three, and will be related to the foundational holy war at the Red Sea. Included in chapter three will be a study of the Divine Warrior, the Song of Moses, the plagues which are described in connection with the seven trumpets and seven bowls, and the dragon. Chapter four will survey other significant references to the Exodus in the Apocalypse, including a study of the Lamb, iii the angel of His presence, the Shepherd, and the expressions the people of God, a kingdom and priests, and the One who is, was, and is coming. Each of these topics will serve to further demonstrate the use of the Exodus motif in the Revelation. A statement of conclusions and observations will follow chapter four

Is nonhelical hydromagnetic turbulence peaked at small scales?

Nonhelical hydromagnetic turbulence without an imposed magnetic field is considered in the case where the magnetic Prandtl number is unity. The magnetic field is entirely due to dynamo action. The magnetic energy spectrum peaks at a wavenumber of about 5 times the minimum wavenumber in the domain, and not at the resistive scale, as has previously been argued. Throughout the inertial range the spectral magnetic energy exceeds the kinetic energy by a factor of about 2.5, and both spectra are approximately parallel. At first glance, the total energy spectrum seems to be close to k^{-3/2}, but there is a strong bottleneck effect and it is suggested that the asymptotic spectrum is k^{-5/3}. This is supported by the value of the second order structure function exponent that is found to be \zeta_2=0.70, suggesting a k^{-1.70} spectrum.Comment: 6 pages, 6 figure

Case studies of farm demonstration in Norway report 1: Promoting optimal soil culture

publishedVersio

Case studies of farm demonstration in Norway report 2: Promoting berry production in plastic tunnels

publishedVersio

Suppression of small scale dynamo action by an imposed magnetic field

Non-helical hydromagnetic turbulence with an externally imposed magnetic field is investigated using direct numerical simulations. It is shown that the imposed magnetic field lowers the spectral magnetic energy in the inertial range. This is explained by a suppression of the small scale dynamo. At large scales, however, the spectral magnetic energy increases with increasing imposed field strength for moderately strong fields, and decreases only slightly for even stronger fields. The presence of Alfven waves is explicitly confirmed by monitoring the evolution of magnetic field and velocity at one point. The frequency omega agrees with vA k1, where vA is the Alfven speed and k1 is the smallest wavenumber in the box.Comment: Final version (7 pages

The scaling properties of dissipation in incompressible isotropic three-dimensional magnetohydrodynamic turbulence

The statistical properties of the dissipation process constrain the analysis of large scale numerical simulations of three dimensional incompressible magnetohydrodynamic (MHD) turbulence, such as those of Biskamp and Muller [Phys. Plasmas 7, 4889 (2000)]. The structure functions of the turbulent flow are expected to display statistical self-similarity, but the relatively low Reynolds numbers attainable by direct numerical simulation, combined with the finite size of the system, make this difficult to measure directly. However, it is known that extended self-similarity, which constrains the ratio of scaling exponents of structure functions of different orders, is well satisfied. This implies the extension of physical scaling arguments beyond the inertial range into the dissipation range. The present work focuses on the scaling properties of the dissipation process itself. This provides an important consistency check in that we find that the ratio of dissipation structure function exponents is that predicted by the She and Leveque [Phys. Rev. Lett 72, 336 (1994)] theory proposed by Biskamp and Muller. This supplies further evidence that the cascade mechanism in three dimensional MHD turbulence is non-linear random eddy scrambling, with the level of intermittency determined by dissipation through the formation of current sheets.Comment: 9 pages, 6 figures. Figures embedded in text. Typos corrected in text and references. Published in Physics of Plasmas. Abstract can be found at:http://link.aip.org/link/?php/12/02230

Addressing seed security in disaster response - linking relief with development

This volume contains eight case studies managed by CIAT, CRS, and CARE Norway in a project entitled, Assisting disaster-affected and chronically stressed communities in East, Central and Southern Africa: Focus on small farmer systems. The case studies were undertaken to evaluate various forms of emergency seed aid and to couple these with analyses of the broader seed and crop systems. The objectives were to understand if and how vulnerable farmers are being helped by the kinds of assistance they receive —and how to move forward on improving practice

Skylab imagery: Application to reservoir management in New England

The author has identified the following significant results. S190B imagery is superior to the LANDSAT imagery for land use mapping and is as useful for level 1 and 2 land use mapping as the RB-57/RC8 high altitude imagery. Detailed land use mapping at levels 3 and finer from satellite imagery requires better resolution. For evaluating factors that are required to determine volume runoff potentials in a watershed, the S190B imagery was found to be as useful as the RB-57/RC8 high altitude aircraft imagery