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Selecting and investing in stock market with right proportions is one of the major challenges. Majority of the investors end up losing their invested equity capital due to uncertainty in the market. The present study provides a novel framework for novice investors to construct portfolio based on multicriteria decision making techniques under fuzzy environment. The scores obtained from these techniques were used to introduce two non-dimensional parameters for categorization of risky and non-risky assets. Three perceptions portfolios were constructed based on the proposed non-dimensional parameters along with fractional lion clustering algorithm. In order to demonstrate the proposed framework, an illustrative application is included in equity portfolio selection. The returns and risks of these perception based portfolios are compared to major Index funds for validating the efficiency and are found to overpower the Index funds with significant margins by maintaining the risk comparable to Index funds. Further, Markowitz based efficient frontier is plotted for better understanding of optimal returns and risk for perception based investment.

Fluctuations in temperature non-uniformity along the line-of-sight of a diode laser absorption sensor in a model scramjet are found to precede backpressure-induced unstart (expulsion of the isolator shock train). A novel detection strategy combining Fourier analysis of temperature time series to determine low-frequency heat release fluctuations with simultaneous measurements of multiple absorption features of H2O to identify temperature non-uniformities was applied to the scramjet combustor. Time-resolved absorption is measured using wavelength modulation spectroscopy for three transitions chosen with different temperature-dependent absorption characteristics. The line-of-sight (LOS)-averaged temperature inferred from the ratio of absorption from one pair of transitions is highly sensitive to low-temperature nonuniformities along the absorption path while the other ratio is less sensitive. The fraction of fluctuations in the range 1 < f < 50 Hz is determined from short-time Fourier transforms (STFTs) of the measured temperatures from both transition pairs., Published in the Proceedings of the Combustion Institute, v32 p831-838, 2009. Prepared in collaboration with Stanford University, Stanford, CA, and with Innovative Scientific Solutions, Inc., Dayton, OH.

An advanced long duration, high enthalpy direct connect water cooled supersonic combustion research facility has been designed and manufactured; initial calibrations have been performed. This facility provides the AFRL/PRS division with in house capability to conduct long duration scramjet combustor research and development. Simulations of flight Mach numbers to 7+ at flight dynamic pressures to 2000 psf are achievable using four separate facility nozzles (M=1.8, 2.2, 2.6, and 3.0). These efforts are directed at developing advanced propulsion systems for future Air Force high speed flight vehicles. In less than twenty four months, concepts and ideas for a scramjet test facility were analyzed and developed, and components were designed, fabricated, and installed to build an operational scramjet test facility. Components were assembled in Test Cell 22 at AFRL Bldg. 18E. The majority of the components (vitiator, inlet transition, facility nozzle, isolator sections, and fixed and traversing probes) are water cooled. The combustor test section provides a wide parametric space for evaluating fuel injection and flameholding concepts. The AFRL/PRSS Scramjet Test Facility is fully operational and a series of preliminary calibration tests have been completed to fully document the flow characteristics at the combustor inlet for a wide range of flight Mach numbers and dynamic pressures. Data from these tests are presented herein.