Sreekumar, R; Thrivikraman,T; Chakravarti, R S(Department of Mathematics, Faculty of Science, 2002)
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Abstract:
The main purpose of the study is to extent concept of the class of spaces called ‘generalized metric spaces’ to fuzzy context and investigates its properties. Any class of spaces defined by a property possessed by all metric spaces could technically be called as a class of ‘generalized metric spaces’. But the term is meant for classes, which are ‘close’ to metrizable spaces in some under certain kinds of mappings. The theory of generalized metric spaces is closely related to ‘metrization theory’. The class of spaces likes Morita’s M- spaces, Borges’s w-spaces, Arhangelskii’s p-spaces, Okuyama’s spaces have major roles in the theory of generalized metric spaces. The thesis introduces fuzzy metrizable spaces, fuzzy submetrizable spaces and proves some characterizations of fuzzy submetrizable spaces, and also the fuzzy generalized metric spaces like fuzzy w-spaces, fuzzy Moore spaces, fuzzy M-spaces, fuzzy k-spaces, fuzzy -spaces study of their properties, prove some equivalent conditions for fuzzy p-spaces. The concept of a network is one of the most useful tools in the theory of generalized metric spaces. The -spaces is a class of generalized metric spaces having a network.
Reji,Srinivas; Sajan,K(Department of Marine Geology and Geophysics, School of marine Sciences, 2002)
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Abstract:
In this study, an attempt has been made to find the textural, geochemical, sedimentological characteristics of sediments and water phases of the kayamkulam estuary located in the Southwest coast of Kerala, besides the impact of gas based thermal power plant located at the northern part of the estuary. Estuaries are an important stage in the transport of the solid weathering product of the earth’s crust. These weathered products or sediments are complex mixtures of a number of solid phases that may include clays, silica, organic matter, metal oxides, carbonates, sulfides and a number of minerals. Studies on the aquatic systems revealed the fact that it posses severe ecological impairments due to heavy discharge of sediments from 44 rivers, the continued disposal of pollutants rich materials from industries, sewage channels, agricultural areas and retting yards
Abdul Sathar,E I; Muraleedharan Nair,K R(Department of Statistics, Faculty of Science, 2002)
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Abstract:
The present study focuses attention on defining certain measures of income inequality for the truncated distributions and characterization of probability distributions using the functional form of these measures, extension of some measures of inequality and stability to higher dimensions, characterization of bivariate models using the above concepts and estimation of some measures of inequality using the Bayesian techniques. The thesis defines certain measures of income inequality for the truncated distributions and studies the effect of truncation upon these measures. An important measure used in Reliability theory, to measure the stability of the component is the residual entropy function. This concept can advantageously used as a measure of inequality of truncated distributions. The geometric mean comes up as handy tool in the measurement of income inequality. The geometric vitality function being the geometric mean of the truncated random variable can be advantageously utilized to measure inequality of the truncated distributions. The study includes problem of estimation of the Lorenz curve, Gini-index and variance of logarithms for the Pareto distribution using Bayesian techniques.
Jose,V S; Sankaranarayanan,K C(Department of Applied Economics, 2002)
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Abstract:
The present study was undertaken to evaluate the performance of Coir Vyavasaya Co-operative societies (CVCs) in Kerala. It was also intended to examine the extent of fulfillment of the objectives of Co-operativisation Scheme and the socio-economic betterment of worker members, Further the study was directed to find out the level of participation of members in the affairs of CVCs and to identify the major problems confronting the CVCs and the future prospects of the industry. The objectives of this study are to evaluate the performance of CVCs in Kerala with reference to the objectives of co-operativisation, socio-economic background of the worker members of the CVCs in the state, extent of members participation, major problems etc. Major findings of the study shows that 84% of CVCs surveyed were incurring losses, the long-term solvency position of the CVCS shows very pathetic situation, ration analysis shows and unhealthy state of affaires with respect to short-term solvency position and operating efficiency of all categories of CVS were found to be extremely poor. If CVCs are enabled to increase their quantity of production and there by the volume of business, their amount of loss can be reduced. If this is so, the societies can provide more days of employment to their work members, which will help them to earn more wages and thereby improve their economic and social conditions
Sona,Kundukulam O; Manju,Paulson; Aanandan,C K; Mohanan, P(Microwave and Optical Technology Letters, August 5, 2002)
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Abstract:
Development of a new compact circular-sided microstrip
antenna is presented. This antenna offers considerable area re- TABLE 2. Variation of Resonant Frequencies
duction compared to standard rectangular microstrip antenna designed
for the same frequency. Typical antenna design and
experimental results for circular polarization are also demonstrated.
77je antenna has a 3-dB axial ratio bandwidth of 1.5%
Shyam S,Pattnaik; Dhruba C,Panda; Devi,S(Microwave and Optical Technology Letters, September 20, 2002)
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Abstract:
The mathematical formulation of empirically developed formulas Jirr the calculation of the resonant frequency of a thick-substrate
(h s 0.08151 A,,) microstrip antenna has been analyzed. With the
use qt' tunnel-based artificial neural networks (ANNs), the resonant frequency
of antennas with h satisfying the thick-substrate condition are
calculated and compared with the existing experimental results and also
with the simulation results obtained with the use of an IE3D software
package. The artificial neural network results are in very good agreement
with the experimental results
Donghyun,Kim; Sangseol,Lee(Microwave and Optical Technology Letters, July 20, 2002)
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Abstract:
Most adaptive linearization circuits for the nonlinear amplifier
have a feedback loop that returns the output signal oj'tne eunplifier
to the lineurizer. The loop delay of the linearizer most be controlled
precisely so that the convergence of the linearizer should be assured lot
this Letter a delay control circuit is presented. It is a delay lock loop
(ULL) with it modified early-lute gate and can he easily applied to a
DSP implementation. The proposed DLL circuit is applied to an adaptive
linearizer with the use of a polynomial predistorter, and the simulalion
for a 16-QAM signal is performed. The simulation results show that
the proposed DLL eliminates the delay between the reference input signal
and the delayed feedback signal of the linearizing circuit perfectly,
so that the predistorter polynomial coefficients converge into the optimum
value and a high degree of linearization is achieved
Janat Augustine, K; Dr.Chandramohanakumar, N(Cochin University of Science & Technology, September , 2002)
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Abstract:
Humic substances are complex polymeric structures.No other polymers with such a wide range of properties are so widely distributed in nature.But still their moleculer structures are unknown. A structural knowledge is essential in determining their reactivity with metals.In the present work structural elucidation of humic acids from three different mangrove ecosystems of Cochin area is done with the available data from functional group analysis and various spectroscopic methods.13C NMR spectra of the solid samples with CPMAS,IR and SEM are very promising in revealing the complex structures of these polymeric substances.Sorptional studies on the sediment and humic acid of mangrove ecosystem reveals that the major portion of the organic matter is not extractable with Sodium hydroxide and humic acid only a small portion of the total organic matter. Humic acid is a good complexing agent and scavenger. Due to the nonextractable nature of the organic matter present with the sediment left after alkali extraction it is a better scavenger.
Description:
Department of Chemical Oceanography,Cochin University of Science and Technology