Studies related to ocean dynamics. Task 3.2: Aircraft Field Test Program to investigate the ability of remote sensing methods to measure current/wind-wave interactions

The feasibility of remote sensing of current flows in the ocean and the remote sensing of ocean currents by backscattering cross section techniques was studied. It was established that for capillary waves, small scale currents could be accurately measured through observation of wave kinematics. Drastic modifications of waves by changing currents were noted. The development of new methods for the measurement of capillary waves are discussed. Improvement methods to resolve data processing problems are suggested

X-ray Emission from Magnetically Torqued Disks of Oe/Be Stars

We focus attention on the Oe/Be stars to test the concept that the disks of these stars form by magnetic channeling of wind material toward the equator. Calculations are made of the X-rays expected from the Magnetically Torqued Disk (MTD) model for Be stars discussed by Cassinelli et al. (2002), by Maheswaran (2003), and by Brown et al. (2004). The dominant parameters in the model are the $\beta$ value of the velocity law, the rotation rate of the star, $S_o$, and the ratio of the magnetic field energy density to the disk gravitational energy density, $\gamma$. The model predictions are compared with the $ROSAT$ observations obtained for an O9.5 star $\zeta$ Oph from \Berghofer et al. (1996) and for 7 Be stars from Cohen et al. (1997). Extra considerations are also given here to the well studied Oe star $\zeta$ Oph for which we have $Chandra$ observations of the X-ray line profiles of the triad of He-like lines from the ion Mg XI.Comment: 28 pages with 6 figures. Accepted for publication in Ap

An absorption spectrum amplifier for determining gas composition

Compositions of gas samples are frequently studied by laser absorption spectroscopy. Sensitivity is improved by two orders of magnitude when absorption cell is placed inside an organic-dye laser cavity

Water-depth measurement by wave refraction and multispectral techniques

Shallow ocean depth measurements by aerial photographs of wave refraction and wavelength changes and by multispectral scanning of wave reflectio

The energy requirement of farming in New Zealand

This report presents the findings of a study of the direct and indirect energy use by the New Zealand farming sector on a 'to-farm-gate' basis. Although detailed statistics are available on this sector in financial terms, little data has been collected on inputs to agriculture in physical terms, and this complicates the application of energy analysis. This report therefore provides complete detail on all working calculations and the assumptions made, so that through wide distribution of these findings and the resulting feedback, the study estimates may be more precisely defined and the resulting energy requirement data improved

New Zealand arable sector : foreign exchange implications

This report presents the findings of a study into the foreign exchange earnings of the arable sector in New Zealand. The F.O.B. value of arable sector products (or C.I.F. value of wheat) is assessed and from this the foreign exchange component of crop inputs is deducted. The major cropping enterprises are then compared with livestock production in the arable sector. In Chapter 2 the basic concept for assessing the foreign exchange (F.E.) of on farm production costs is discussed in detail while Chapter 3 describes the arable sector in New Zealand and assesses the volume and value of arable production as well as trends in land use patterns. Chapter 4 evaluates the foreign exchange requirement (imports) of the major crop and Livestock enterprises in the arable sector while the gross foreign exchange earnings (exports) of these enterprises are assessed in Chapter 5. Chapter 6 compares the net foreign exchange earnings with the returns actually experienced by the grower and looks at the foreign exchange earnings of various band use options. Chapter 7 concludes the report

Effects of Process Variables and Size Scale on Solidification Microstructure in Laser-Based Solid Freeform Fabrication of Ti-6Al-4V

Mechanical Engineerin

Positivity of Entropy in the Semi-Classical Theory of Black Holes and Radiation

Quantum stress-energy tensors of fields renormalized on a Schwarzschild background violate the classical energy conditions near the black hole. Nevertheless, the associated equilibrium thermodynamical entropy $\Delta S$ by which such fields augment the usual black hole entropy is found to be positive. More precisely, the derivative of $\Delta S$ with respect to radius, at fixed black hole mass, is found to vanish at the horizon for {\it all} regular renormalized stress-energy quantum tensors. For the cases of conformal scalar fields and U(1) gauge fields, the corresponding second derivative is positive, indicating that $\Delta S$ has a local minimum there. Explicit calculation shows that indeed $\Delta S$ increases monotonically for increasing radius and is positive. (The same conclusions hold for a massless spin 1/2 field, but the accuracy of the stress-energy tensor we employ has not been confirmed, in contrast to the scalar and vector cases). None of these results would hold if the back-reaction of the radiation on the spacetime geometry were ignored; consequently, one must regard $\Delta S$ as arising from both the radiation fields and their effects on the gravitational field. The back-reaction, no matter how "small",Comment: 19 pages, RevTe