Rejeesh C, John; Dr. Asha, Gopalakrishnan(Cochin University of Science & Technology, February , 2011)
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Abstract:
In this thesis, the concept of reversed lack of memory property and its generalizations
is studied.We we generalize this property which involves operations different
than the ”addition”. In particular an associative, binary operator ” * ” is considered. The
univariate reversed lack of memory property is generalized using the binary operator
and a class of probability distributions which include Type 3 extreme value, power
function, reflected Weibull and negative Pareto distributions are characterized (Asha
and Rejeesh (2009)). We also define the almost reversed lack of memory property
and considered the distributions with reversed periodic hazard rate under the binary
operation. Further, we give a bivariate extension of the generalized reversed lack of
memory property and characterize a class of bivariate distributions which include the
characterized extension (CE) model of Roy (2002a) apart from the bivariate reflected
Weibull and power function distributions. We proved the equality of local proportionality
of the reversed hazard rate and generalized reversed lack of memory property. Study of uncertainty is a subject of interest common to reliability, survival analysis,
actuary, economics, business and many other fields. However, in many realistic
situations, uncertainty is not necessarily related to the future but can also refer to the
past. Recently, Di Crescenzo and Longobardi (2009) introduced a new measure of information
called dynamic cumulative entropy. Dynamic cumulative entropy is suitable
to measure information when uncertainty is related to the past, a dual concept of the
cumulative residual entropy which relates to uncertainty of the future lifetime of a system.
We redefine this measure in the whole real line and study its properties. We also
discuss the implications of generalized reversed lack of memory property on dynamic
cumulative entropy and past entropy.In this study, we extend the idea of reversed lack of memory property to the
discrete set up. Here we investigate the discrete class of distributions characterized by
the discrete reversed lack of memory property. The concept is extended to the bivariate
case and bivariate distributions characterized by this property are also presented. The
implication of this property on discrete reversed hazard rate, mean past life, and discrete past entropy are also investigated.
Description:
Department of Statistics,
Cochin University of Science and Technology
Leeju, P; Dr.Mohammed Yusuff, K K(Cochin University of Science & Technology, April , 2011)
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Abstract:
In this thesis we report the synthsis and characterisation of new transition metal complexes of Pd(II),Cu(II),Ru(II) and Ir(III) of Schiff bases derived from quinoxaline-2-carboxaldehyde/3-hydroxyquinoxaline-2-carboxaldehyde and 5-aminoindazole.6-aminoindazole or 8-aminoquinoline.The complexes have been characterised by spectral and analytical data.Pd(II) and Cu(II) form square planar complexes and Ru(III) and Ir(III) form ctahedral complexes with these Schiff bases.The DNA binding properties of theses synthesised complexes have been studied by various methods including electronic absoption spectroscopy,cyclic voltammetry,different pulse voltammetry and circular dichroism spectra were used.Gel electrophoresis experiments were also performed to investigate the DNA cleavage of theses complexes.Furthermore Ru(III) and Ir(III) complexes find application as oxidation and hydogenation catalsts. The studies on catalytic activities has been presented.The metal complexes presented in this thesis assure significance as they contribute to the development of new DNA binding agents and antibacterial and anticancer drugs.
Description:
Dept.of Applied Chemistry,Cochin University of Science and Technology
Renjith, V R; Dr. Madhu, G(Cochin University of Science & Technology, July , 2010)
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Abstract:
The hazards associated with major accident hazard (MAH) industries
are fire, explosion and toxic gas releases. Of these, toxic gas release is the worst
as it has the potential to cause extensive fatalities. Qualitative and quantitative
hazard analyses are essential for the identitication and quantification of the
hazards associated with chemical industries. This research work presents the
results of a consequence analysis carried out to assess the damage potential of
the hazardous material storages in an industrial area of central Kerala, India. A
survey carried out in the major accident hazard (MAH) units in the industrial
belt revealed that the major hazardous chemicals stored by the various industrial
units are ammonia, chlorine, benzene, naphtha, cyclohexane, cyclohexanone
and LPG. The damage potential of the above chemicals is assessed using
consequence modelling. Modelling of pool fires for naphtha, cyclohexane,
cyclohexanone, benzene and ammonia are carried out using TNO model. Vapor
cloud explosion (VCE) modelling of LPG, cyclohexane and benzene are carried
out using TNT equivalent model. Boiling liquid expanding vapor explosion
(BLEVE) modelling of LPG is also carried out. Dispersion modelling of toxic
chemicals like chlorine, ammonia and benzene is carried out using the ALOHA
air quality model. Threat zones for different hazardous storages are estimated
based on the consequence modelling. The distance covered by the threat zone
was found to be maximum for chlorine release from a chlor-alkali industry
located in the area. The results of consequence modelling are useful for the
estimation of individual risk and societal risk in the above industrial area.Vulnerability assessment is carried out using probit functions for toxic,
thermal and pressure loads. Individual and societal risks are also estimated at
different locations. Mapping of threat zones due to different incident outcome
cases from different MAH industries is done with the help of Are GIS.Fault Tree Analysis (FTA) is an established technique for hazard
evaluation. This technique has the advantage of being both qualitative and
quantitative, if the probabilities and frequencies of the basic events are known.
However it is often difficult to estimate precisely the failure probability of the
components due to insufficient data or vague characteristics of the basic event.
It has been reported that availability of the failure probability data pertaining to
local conditions is surprisingly limited in India. This thesis outlines the
generation of failure probability values of the basic events that lead to the
release of chlorine from the storage and filling facility of a major chlor-alkali
industry located in the area using expert elicitation and proven fuzzy logic.
Sensitivity analysis has been done to evaluate the percentage contribution of
each basic event that could lead to chlorine release. Two dimensional fuzzy
fault tree analysis (TDFFTA) has been proposed for balancing the hesitation
factor invo1ved in expert elicitation .
Description:
Division of Safety and Fire Engineering,
School of Engineering,
Cochin University of Science and Technology
Sudheer, Sebastian K(Cochin University of Science and Technology, June , 2010)
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Abstract:
FPS is a more general form of synchronization. Hyperchaotic systems possessing
more than one positive Lypaunov exponent exhibit highly complex behaviour and
are more suitable for some applications like secure communications. In this thesis
we report studies of FPS and MFPS of a few chaotic and hyperchaotic systems.
When all the parameters of the system are known we show that active nonlinear
control method can be efectively used to obtain FPS. Adaptive nonlinear control
and OPCL control method are employed for obtaining FPS and MFPS when some or
all parameters of the system are uncertain. A secure communication scheme based
on MFPS is also proposed in theory. All our theoretical calculations are verified by
numerical simulations.
Description:
Department of Physics,
Cochin University of Science and Technology