Multistage multiple-reentry turbine Patent

Multistage, multiple reentry, single rotor, axial flow turbin

Collisional dynamics of perturbed particle disks in the solar system

Investigations of the collisional evolution of particulate disks subject to the gravitational perturbation of a more massive particle orbiting within the disk are underway. Both numerical N-body simulations using a novel collision algorithm and analytical kinetic theory are being employed to extend our understanding of perturbed disks in planetary rings and during the formation of the solar system. Particular problems proposed for investigation are: (1) The development and testing of general criteria for a small moonlet to clear a gap and produce observable morphological features in planetary rings; (2) The development of detailed models of collisional damping of the wavy edges observed on the Encke division of Saturn's A ring; and (3) The determination of the extent of runaway growth of the few largest planetesimals during the early stages of planetary accretion

Multistage multiple-reentry turbine Patent

Multistage multiple reentry axial flow reaction turbine with reverse flow reentry ductin

Near infrared spectroscopy for fibre based gas detection

Gas sensing systems based on fibre optic linked near infra red absorption cells are potentially a flexible and effective tool for monitoring accumulations of hazardous and noxious gases in enclosed areas such as tunnels and mines. Additionally the same baseline technology is readily modified to measure concentrations of hydrocarbon fuels - notably but not exclusively methane, and monitoring emissions of greenhouse gases. Furthermore the system can be readily implemented to provide intrinsically safe monitoring over extensive areas at up to ~250 points from a single interrogation unit. In this paper we review our work on fibre coupled gas sensing systems. We outline the basic principles through which repeatable and accurate self calibrating gas measurements may be realised, including the recover of detailed line shapes for non contact temperature and / or pressure measurements in addition to concentration assessments in harsh environments. We also outline our experience in using these systems in extensive networks operating under inhospitable conditions over extended periods extending to several years

Rosetak Document 4: Rank Degeneracies and Least Square Problems

In this paper we shall be concerned with the following problem. Let A be an m x n matrix with m being greater than or equal to n, and suppose that A is near (in a sense to be made precise later) a matrix B whose rank is less than n. Can one find a set of linearly independent columns of A that span a good approximation to the column space of B? The solution of this problem is important in a number of applications. In this paper we shall be chiefly interested in the case where the columns of A represent factors or carriers in a linear model which is to be fit to a vector of observations b. In some such applications, where the elements of A can be specified exactly (e.g. the analysis of variance), the presence of rank degeneracy in A can be dealt with by explicit mathematical formulas and causes no essential difficulties. In other applications, however, the presence of degeneracy is not at all obvious, and the failure to detect it can result in meaningless results or even the catastrophic failure of the numerical algorithms being used to solve the problem. The organization of this paper is the following. In the next section we shall give a precise definition of approximate degeneracy in terms of the singular value decomposition of A. In Section 3 we shall show that under certain conditions there is associated with A a subspace that is insensitive to how it is approximated by various choices of the columns of A, and in Section 4 we shall apply this result to the solution of the least squares problem. Sections 5, 6, and 7 will be concerned with algorithms for selecting a basis for the stable subspace from among the columns of A.

The Gram-Schmidt Algorithm and Its Variations

The Gram--Schmidt algorithm is a widely used method for orthogonalizing a sequence of vectors. It comes in two forms: classical Gram--Schmidt and modified Gram--Schmidt, each of whose operations can be ordered in different ways. This expository paper gives a systematic treatment of this confusing variety of algorithms. It also treats the numerical issue of loss of orthogonality and reorthogonalization as well as the implementation of column pivoting

A Comparison of Power Output Conical, Hyperbolic and Exponential Trumpets

These measurements are presented as illustrative of the advances that have been made in the measurement of acoustic power. They refer of course to single cases, but they are of interest in showing the actual fluctuations of both components of impedance and of the power output in the three types of trumpets stated in the title

The Binaural Difference of Phase Effect

The binaural difference of phase effect has become of increased importance in recent years. The following are the new facts obtained in recent experiments which are still in progress

The Action of Cylindrical Tubes in Branch Acoustic Lines

Quincke\u27s tube has long been known. A theoretical and experimental study of its action is herewith reported. Also the formulas for an open tube as well as a closed tube have been derived. The experimental results show unmistakable evidence of the viscosity. The selective property of Quincke\u27s tube is ascertained both experimentally and theoretically for the first time