Evaluation of TILS for use as the orbiter landing NAVAID

An evaluation of the tactical instrument landing systems (TILS) for use in the orbiter autoland system was made. It was found that with certain modifications, the TILS can satisfy orbiter autoland requirements. These modifications, include (1) addition of DME equipment, (2) expansion of elevation coverage from 0-10 deg to 0-30 deg, and (3) expansion to redundant systems with associated ground monitors. Additional modifications that are not necessary to meet the orbiter requirements, but that can enhance performance margin are (1) tightening of elevation antenna beam width from 1.3 deg to 0.5 deg and (2) split site configuration to provide azimuth and range coverage through rollout

On the etale cohomology of algebraic varieties with totally degenerate reduction over p-adic fields

Let K be a finite extension of Q_p and X a smooth projective variety over K. We define the notion of totally degenerate reduction of such an X and the associated Chow complexes of the special fibre of a suitable regular proper model of X over the ring of integers of K. If X has such reduction, we then show that for all l, the Q_l-adic etale cohomology of X has a filtration whose graded quotients are isomorphic, as Galois modules, to the tensor product of a finite dimensional Q-vector space (with a finite unramified action of Galois) with twists of Q_l by the cyclotomic character.Comment: 29 pages This and math.AG/0601401 replace math.AG/030612

Evaluation and demonstration of a propellant quantity gaging system for auxiliary propulsion systems Final report

Bipropellant quantity gaging digital syste

Advanced flight deck/crew station simulator functional requirements

This report documents a study of flight deck/crew system research facility requirements for investigating issues involved with developing systems, and procedures for interfacing transport aircraft with air traffic control systems planned for 1985 to 2000. Crew system needs of NASA, the U.S. Air Force, and industry were investigated and reported. A matrix of these is included, as are recommended functional requirements and design criteria for simulation facilities in which to conduct this research. Methods of exploiting the commonality and similarity in facilities are identified, and plans for exploiting this in order to reduce implementation costs and allow efficient transfer of experiments from one facility to another are presented

The Role of Environmental Payments in Sustaining Farm Incomes: A Four Year Study of Farm Businesses in an Upland Area of the UK

A representative sample of both participant and non-participant case study farms was examined over a three-year period in the Shropshire Hills Environmentally Sensitive Area of the UK from 1997 to 2000. The effects on farm business viability were monitored and results compared with two relevant sub samples of Farm Business Survey recorded farms. The study showed that farming profitability declined sharply over the study period but that participant case study farm profitability exceeded that of non-participants by an average of £4024 per year. This was attributable to a combination of factors which included larger average farm size, the ESA premium and more intensive farming operations. Subsidies received by both types of farms were almost totally on the "per head" basis and averaged £270 per hectare. Without these both classes of farms would have been highly unprofitable. The status of the ESA premium compared with these figures was an average of 4.5 percent of business turnover or £2358 per farm, well below that of headage based subsidies. Return on capital invested in land was consistently low, suggesting that even with these levels of subsidies the long-term future of these farms could be uncertain. The results achieved were consistent with those obtained from the Farm Business Survey data provided for the two relevant sub-samples.Farm Management,

Gauge Field Preheating at the End of Inflation

Here we consider the possibility of preheating the Universe via the parametric amplification of a massless, U(1) abelian gauge field. We assume that the gauge field is coupled to the inflaton via a conformal factor with one free parameter. We present the results of high-resolution three-dimensional simulations of this model and show this mechanism efficiently preheats the Universe to a radiation-dominated final state.Comment: 8 pages, 8 figure

Realizability of the Lorentzian (n,1)-Simplex

In a previous article [JHEP 1111 (2011) 072; arXiv:1108.4965] we have developed a Lorentzian version of the Quantum Regge Calculus in which the significant differences between simplices in Lorentzian signature and Euclidean signature are crucial. In this article we extend a central result used in the previous article, regarding the realizability of Lorentzian triangles, to arbitrary dimension. This technical step will be crucial for developing the Lorentzian model in the case of most physical interest: 3+1 dimensions. We first state (and derive in an appendix) the realizability conditions on the edge-lengths of a Lorentzian n-simplex in total dimension n=d+1, where d is the number of space-like dimensions. We then show that in any dimension there is a certain type of simplex which has all of its time-like edge lengths completely unconstrained by any sort of triangle inequality. This result is the d+1 dimensional analogue of the 1+1 dimensional case of the Lorentzian triangle.Comment: V1: 15 pages, 2 figures. V2: Minor clarifications added to Introduction and Discussion sections. 1 reference updated. This version accepted for publication in JHEP. V3: minor updates and clarifications, this version closely corresponds to the version published in JHE

Ionization of Rydberg atoms embedded in an ultracold plasma

We have studied the behavior of cold Rydberg atoms embedded in an ultracold plasma. We demonstrate that even deeply bound Rydberg atoms are completely ionized in such an environment, due to electron collisions. Using a fast pulse extraction of the electrons from the plasma we found that the number of excess positive charges, which is directly related to the electron temperature Te, is not strongly affected by the ionization of the Rydberg atoms. Assuming a Michie-King equilibrium distribution, in analogy with globular star cluster dynamics, we estimate Te. Without concluding on heating or cooling of the plasma by the Rydberg atoms, we discuss the range for changing the plasma temperature by adding Rydberg atoms.Comment: To be published in P.R.