Adaptive identification and control of structural dynamics systems using recursive lattice filters

A new approach for adaptive identification and control of structural dynamic systems by using least squares lattice filters thar are widely used in the signal processing area is presented. Testing procedures for interfacing the lattice filter identification methods and modal control method for stable closed loop adaptive control are presented. The methods are illustrated for a free-free beam and for a complex flexible grid, with the basic control objective being vibration suppression. The approach is validated by using both simulations and experimental facilities available at the Langley Research Center

A Methodology for Afterburner Evaluation

A preliminary investigation of the performance of an afterburner module proposed by the Gas Turbine Research Establishment, Bangalore for the Kaveri engine has been carried out. The investigation, which was both theoretical and experimental, evaluated the af-terburner configuration on the basis of flame stability, combustion efficiency and total pressure loss. An evaluation methodology, which was formulated, has been employed to arrive at design modifications for improved performance

Towards adiabatic waveforms for inspiral into Kerr black holes: I. A new model of the source for the time domain perturbation equation

We revisit the problem of the emission of gravitational waves from a test mass orbiting and thus perturbing a Kerr black hole. The source term of the Teukolsky perturbation equation contains a Dirac delta function which represents a point particle. We present a technique to effectively model the delta function and its derivatives using as few as four points on a numerical grid. The source term is then incorporated into a code that evolves the Teukolsky equation in the time domain as a (2+1) dimensional PDE. The waveforms and energy fluxes are extracted far from the black hole. Our comparisons with earlier work show an order of magnitude gain in performance (speed) and numerical errors less than 1% for a large fraction of parameter space. As a first application of this code, we analyze the effect of finite extraction radius on the energy fluxes. This paper is the first in a series whose goal is to develop adiabatic waveforms describing the inspiral of a small compact body into a massive Kerr black hole.Comment: 21 pages, 6 figures, accepted by PRD. This version removes the appendix; that content will be subsumed into future wor

Towards adiabatic waveforms for inspiral into Kerr black holes: II. Dynamical sources and generic orbits

This is the second in a series of papers whose aim is to generate ``adiabatic'' gravitational waveforms from the inspiral of stellar-mass compact objects into massive black holes. In earlier work, we presented an accurate (2+1)D finite-difference time-domain code to solve the Teukolsky equation, which evolves curvature perturbations near rotating (Kerr) black holes. The key new ingredient there was a simple but accurate model of the singular source term based on a discrete representation of the Dirac-delta function and its derivatives. Our earlier work was intended as a proof of concept, using simple circular, equatorial geodesic orbits as a testbed. Such a source is effectively static, in that the smaller body remains at the same coordinate radius and orbital inclination over an orbit. (It of course moves through axial angle, but we separate that degree of freedom from the problem. Our numerical grid has only radial, polar, and time coordinates.) We now extend the time-domain code so that it can accommodate dynamic sources that move on a variety of physically interesting world lines. We validate the code with extensive comparison to frequency-domain waveforms for cases in which the source moves along generic (inclined and eccentric) bound geodesic orbits. We also demonstrate the ability of the time-domain code to accommodate sources moving on interesting non-geodesic worldlines. We do this by computing the waveform produced by a test mass following a ``kludged'' inspiral trajectory, made of bound geodesic segments driven toward merger by an approximate radiation loss formula.Comment: 14 pages, 5 figures. Accepted by Phys. Rev.

Larval rearing, spat production and juvenile growth of the blood clam Anadara granosa

The blood clam A d r u gmtwsa spawned in the Shdl6lsh Hatchery Laboratory, Tuf icorin on two occasions. The fertilised eggs measured 50-60~in diameter, morula larvae developed in 3 4h m and the trochophorc stage was reached in 5 hrs. The straigb t hinge stage was attained in 20-26 hrs after fertilimtion and these larvae measured 8 3I~en ah and 65.5~h eight. Advanced umbo stage was reached on day 12 (size 155.3 x 140.5~) and on day 16, majority of the larvae were in pedivcliger stage with an average size of 182.7 x 162.9~. SettIement began on day 16 and majority of the larvae were set on day 18. The growth of the spat in the hatchery is described by the exponential equation L - 0.0002739 D - where L is length in mm and D. days. On day 59, tbe spat attained an average size of 2.42 x 1.70 mm. A total of 8090 spat were produced. During tha nursery rearing in the field, the seed clam attained 20 mm average length in the following 5 months. In India, A.grund~llsecd were grodwdfor the Arst time. The significance of this study forthe mass production of the blood clam seed in the bat~herya nd its relevma to undertake blood clam culture are highlighted

The influence of heat treatment on the microstructural, mechanical and corrosion behaviour of cold sprayed SS 316L coatings

The present study evaluates the response of cold sprayed SS 316L coatings on mild steel substrate to aqueous corrosion in a 0.1 N HNO3 solution as determined using polarization tests. The corrosion behaviour of the SS 316L coating was studied not only in the as-coated condition, but also after heat treatment at 400, 800 and 1,100 °C. Heat treatment reduced the porosity, improved inter-splat bonding, increased the elastic modulus and more importantly increased the corrosion resistance of the cold sprayed SS 316L coating

US School Counselor State Licensure Requirements for Program Evaluation

Using qualitative content analysis (Cohen, Manion, & Morrison, 2007), we examined the expectations of states in the US regarding program evaluation content for school counselor licensure. Results show that 43 states maintain some form of program evaluation expectations for licensure, up from the 19 identified by Trevisan (2000). Twenty-eight states require licensure tests that purportedly align with CACREP, ASCA, or maintain a state developed licensure test that measures program evaluation content. Twenty-one states explicitly mention alignment of their curriculum with CACREP, ASCA, or both. The depth and scope of the program evaluation requirements that could be identified are ambiguous and unconnected to best program evaluation practices articulated by the evaluation field. We offer recommendations to build the evaluation capacity of the school counseling profession in the US that include refinements in graduate education of school counselors, in-service training for practicing school counselors, and revision of licensing and program expectations to include standards of best practice in program evaluation