Aged rare earth doped silicates as optoelectronic material

Samples of various concentrations were prepared and kept unsintered for a period of three years to study the consistency of composition prepared and structural evolution of glass. The expanded peaks in the Raman spectra arise due to thermal agitation, and a Boltzmann type of distribution was expected in the silicate gels. The behavior of the gels during the dehydroxylation and dehydration is conditioned by its microstructure, which depends upon the physical conditions, I.e., pH, and drying conditions.     

Synthesis of sub-optimal feedback controls for a class of distributed parameter systems†

Technique are derived for the synthesis of sub-optimal feedback controls for parabolic and first-order hyperbolic systems. An explicit result for the time-invariant gain of a specified controller is obtained by a least square approximation of the closed-loop control to the optimal open-loop control. If a least square approximation of the state trajectories is used, a parameter search is shown to give the time-invariant gain. A time-varying gain can be obtained by a re-definition of the original optimal control problem, again with the controller functionality specified. The only require-mont in the closed-loop synthesis is that an optimal open-loop solution exists and is computable.     

Recursive least-squares parameter estimation in SISO systems via Poisson moment functionals Part 1. Open–loop systems

A recursive least-squares parameter estimation algorithm based on the Poisson moment functional (PMF) approach for S1SO systems in open-loop is presented in this paper. The proposed algorithm is suitable for on-line parameter estimation of real-world problems. Normalized PMFs are used to improve the performance of the algorithm in noisy conditions.     

Deductive efficiency,belief revision and acting

Abstract

The SNePS inference engine is optimized for deductive efficiency, i.e. all beliefs acquired via inference are added to the agent's beliefs so that future queries may be answered by a retrieval rather than rederivation. An assumption-based truth maintenance system keeps track of the derivation histories of derived beliefs. We show how such an architecture simplifies the ontology of prepositional representations of plans; acts; preconditions, and effects of actions. In addition, the deductive efficiency of the basic system automatically extends itself to efficient search of plans, and hierarchical plan decompositions.     

EFFECT OF MANGO PULP AND SOYMILK FORTIFICATION ON THE TEXTURE PROFILE OF SET YOGHURT MADE FROM BUFFALO MILK

The effect of the fat content in buffalo milk and proportions of buffalo milk, soymilk and mango pulp on textural characteristics of mango soy fortified yoghurt (MSFY) is reported. The TA-XT2 Texture Analyzer was used to measure the textural characteristics of MSFY prepared from blends containing varying proportions of buffalo milk (varying fat content), soymilk (8.2% total solids) and mango pulp (18% total solids). Texture profile data were used to develop regression models for dependent variables—hardness (HD), cohesiveness (CO), adhesiveness (AD), springiness (SP) and gumminess (GU), which were used to optimize the blend formula. The optimized values are 2.95% fat content in buffalo milk, 14.7% soymilk and 7.2% mango pulp in the blend for obtaining MSFY having textural characteristics similar to those of yoghurt having 6% fat. The MSFY prepared using optimized blend had HD (108 - 112 g), CO (0.41 - 0.42), AD (- 70.3 to - 72.9 g.s), SP (0.93 - 0.96) and GU (45.05 - 46.38 g).     

A MULTIGRID-ACCELERATED THREE-DIMENSIONAL TRANSIENT-FLOW CODE AND ITS APPLICATION TO A NEW TEST PROBLEM

A multigrid-assisted solver for the three-dimensional time-dependent incompressible Navier-Stokes equations on graded Cartesian meshes is developed. The spatial accuracy is third-order for the convective terms and fourth-order for the viscous terms, and a fractional-step strategy ensures second-order time accuracy. To achieve good time-wise efficiency a multigrid technique is used to solve the highly time-consuming pressure-Poisson equation that requires to be solved at every time step. The speed-up achieved by multigrid is shown in tabular form. The performance and accuracy of the code are first ascertained by computing the flow in a single-sided lid-driven cubic cavity with good grid-economy and comparing the results available in the literature. The code, thus validated, is then applied to a new test problem we propose and various transient and asymptotically obtained steady-state results are presented. Given the care taken to establish the credibility of the code and the good spatio-temporal accuracy of the discretization, these results are accurate and may be used for ascertaining the performance of any computational algorithm applied to this test problem.     

An interval type-2 fuzzy logic controller for TCSC to improve the damping of power system oscillations

In this paper an interval type-2 fuzzy logic controller (IT2FLC) was proposed for thyristor controlled series capacitor (TCSC) to improve power system damping. For controller design, memberships of system variables were represented using interval type-2 fuzzy sets. The three-dimensional membership function of type-2 fuzzy sets provided additional degree of freedom that made it possible to directly model and handle uncertainties. Simulations conducted on a single machine infinite bus (SMIB) power system showed that the proposed controller was more effective than particle swarm optimization (PSO) tuned and type-1 fuzzy logic (T1FL) based damping controllers. Robust performance of the proposed controller was also validated at different operating conditions, various disturbances and parameter variation of the transmission line parameters.     

A Study of Silica-Fume-Modified Cements of Varied Fineness

Pastes and mortars of portland cements with varying fineness were studied. The effect of blending the cements with silica fume up to 10% is presented. Thermogravimetry, heat of hydration, X-ray diffraction, scanning electron microscopy, compressive strengths, and microhardness measurements were used to evaluate the pastes and mortars. The study reveals that properties and strengths of existing portland cements may be enhanced through the addition of silica fume. Coarse cements are benefited greatly through the blending. Energy savings during grinding may be realized through this process.     

STUDIES ON DEEP FAT FRYING USING BLENDED OILS AND POTATO CHIPS

Dehydrated potato chips were fried in pure coconut and groundnut oils and their blends in order to study the pattern of uptake of oil constituents during frying. Investigations on the analysis of the oil and fatty acid composition in the fried product and the oil remaining in the frying pan suggested a preferential uptake of saturated lipid constituents by the potato chips, while the oil remaining in the frying pan was rich in unsaturated constituents. This effect was accentuated in blended oils, although it was also observed in pure oils.