Studies of earth simulation experiments

The low gravity environment of earth orbit offers the potential for performing experiments involving baroclinic Geophysical Fluid Dynamics (GFD) on spherical surfaces. These experiments in turn have the potential for providing deeper understanding of large scale planetary and solar circulations. However, to perform these experiments, one requires an experimental technique whereby a radially directed body force can be generated to simulate a radial gravitational force field. One viable technique is the use of dielectric fluids with temperature dependent dielectric permittivity in a radially directed electric field. Application of the Boussinesq approximation to the equations of motion for this system and restrictions on the size of certain electrodynamic terms in the energy equations yields a set of equations which are analogous to the equations of motions of geophysical systems like the earth's atmosphere on term by term basis. The theoretical design of GFD experiments for performance in earth orbit are described along with results of preliminary tests of a prototype

Active control technology and the use of multiple control surfaces

Needed criteria for active control technology applications in commercial transports are lacking. Criteria for redundancy requirements, believed to be consistent with certification philosophy, are postulated to afford a discussion of the relative value of multiple control surfaces. The control power and frequency bandpass requirements of various active control technology applications are shown to be such that multiple control surfaces offer advantages in minimizing the hydraulic or auxiliary power for the control surface actuators

Limits in compact abelian groups

Let X be compact abelian group and G its dual (a discrete group). If B is an infinite subset of G, let C_B be the set of all x in X such that <phi(x) : phi \in B> converges to 1. If F is a free filter on G, let D_F be the union of all the C_B for B in F. The sets C_B and D_F are subgroups of X. C_B always has Haar measure 0, while the measure of D_F depends on F. We show that there is a filter F such that D_F has measure 0 but is not contained in any C_B. This generalizes previous results for the special case where X is the circle group.Comment: 14 page

Demonstrated results of welded and soldered interconnections

Solar cell modules with welded and soldered interconnections were constructed using a flexible substrate material. These modules were thermally cycled between approx. 80 deg C at rates 100 cycles/day to demonstrate survivability under simulated low Earth orbit (LEO) temperature conditions. The modules, cycled in an inert atmosphere, show durability for 36,000 cycles

Sensitivity of solar-cell performance to atmospheric variables. 2: Dissimilar cells at several locations

Several solar cells having dissimilar spectral response curves and cell construction were measured at various locations in the United States to determine sensitivity of cell performance to atmospheric water vapor and turbidity. The locations selected represent a broad range of summer atmospheric conditions, from clear and dry to turbid and humid. Cell short circuit current under direct normal incidence sunlight, the intensity, water vapor and turbidity were measured. Regression equations were developed from the limited data base in order to provide a single method of prediction of cell current sensitivity to the atmospheric variables

U.S. Farm Policy and the WTO: How Do They Match Up?

The debate over a new farm bill has focused on how to spend an additional $73.5 billion in funding for the agricultural budget over ten years. The House of Representatives, the Senate Agriculture Committee, and Senators Cochran and Roberts (supported by the Bush Administration) have each proposed a structure for the next farm bill. A critical question becomes whether these proposals conflict with U.S. commitments to limit subsidies under the World Trade Organization (WTO) agreement. This paper explores this issue and concludes with a discussion of the future direction of U.S. farm subsidies and new WTO agreements.agricultural policy, domestic support, trade commitments, WTO, Agricultural and Food Policy, International Relations/Trade,

A Spatial Approach to Addressing Weather Derivative Basis Risk: A Drought Insurance Example

Risk and Uncertainty,

U.S. Farm Policy and the World Trade Organization: How Do They Match Up?

The debate over a new farm bill has focused on how to spend an additional $73.5 billion in funding for the agricultural budget over 10 years. The House of Representatives, the Senate agriculture committee, and Senators Cochran and Roberts (supported by the Bush administration) have each proposed a structure for the next farm bill. A critical question becomes whether these proposals conflict with U.S. commitments to limit subsidies under the World Trade Organization (WTO) agreement. This paper explores this issue and concludes with a discussion of the future direction of U.S. farm subsidies and new WTO agreements.