Pramod, Gopinath; Dr.Nampoori,V P N(Cochin University of Science and Technology, April , 2006)
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Abstract:
Developments in laser technology over the past few years have made it possible to do
experiments with focused intensities of IO"-102' Wcm'z. Short-pulse high-intensity
lasers are able to accelerate protons and heavier ions to multi-MeV energies during
their interaction with solid targets, gas jets and clusters. When such a laser radiation
is focused at the intensity above 10” Wcm'2, local electric field strength will be
almost equivalent to that within an atom. Hence, new nonlinear optical phenomena
will be expected in the field of light matter interaction. Most of the research in the
material interaction using high power lasers, especially related to plasma interaction,
has been directed to the short pulse x-ray generation- Nanosecond laser interactions
with solid targets also generate plasmas which emit radiation mainly in the optical
region, the understanding of which is far from satisfactory. This thesis deals with a
detailed study of some of the dynamical processes in plasmas generated by
nanosecond and femtosecond lasers
Description:
lntemational School of Photonics
Cochin University of Science and Technology
Sheena, Mathew; Dr.Poulose Jacob, K(Cochin University of Science and Technology, June , 2008)
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Abstract:
Internet today has become a vital part of day to day life, owing to the
revolutionary changes it has brought about in various fields. Dependence on
the Internet as an information highway and knowledge bank is exponentially
increasing so that a going back is beyond imagination. Transfer of critical
information is also being carried out through the Internet. This widespread use
of the Internet coupled with the tremendous growth in e-commerce and m-commerce
has created a vital need for infonnation security.Internet has also become an active field of crackers and intruders. The
whole development in this area can become null and void if fool-proof security
of the data is not ensured without a chance of being adulterated. It is, hence a
challenge before the professional community to develop systems to ensure
security of the data sent through the Internet.Stream ciphers, hash functions and message authentication codes play
vital roles in providing security services like confidentiality, integrity and
authentication of the data sent through the Internet. There are several ·such
popular and dependable techniques, which have been in use widely, for quite a
long time. This long term exposure makes them vulnerable to successful or
near successful attempts for attacks. Hence it is the need of the hour to
develop new algorithms with better security.Hence studies were conducted on various types of algorithms being
used in this area. Focus was given to identify the properties imparting security
at this stage. By making use of a perception derived from these studies, new algorithms were designed. Performances of these algorithms were then
studied followed by necessary modifications to yield an improved system
consisting of a new stream cipher algorithm MAJE4, a new hash code JERIM-
320 and a new message authentication code MACJER-320. Detailed analysis
and comparison with the existing popular schemes were also carried out to
establish the security levels.The Secure Socket Layer (SSL) I Transport Layer Security (TLS)
protocol is one of the most widely used security protocols in Internet. The
cryptographic algorithms RC4 and HMAC have been in use for achieving
security services like confidentiality and authentication in the SSL I TLS. But
recent attacks on RC4 and HMAC have raised questions about the reliability
of these algorithms. Hence MAJE4 and MACJER-320 have been proposed as
substitutes for them. Detailed studies on the performance of these new
algorithms were carried out; it has been observed that they are dependable
alternatives.
Description:
Department of Computer
Science, Cochin University of Science and Technology
Paul, Isaac; Dr.Chakravarti, R S; Thrivikraman,T(Cochin University of Science and Technology, November , 2004)
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Abstract:
The
main objective of this thesis was to extend some basic concepts and results in
module theory in algebra to the fuzzy setting.The concepts like simple module, semisimple module and exact sequences
of R-modules form an important area of study in crisp module theory. In this
thesis generalising these concepts to the fuzzy setting we have introduced
concepts of ‘simple and semisimple L-modules’ and proved some results which
include results analogous to those in crisp case. Also we have defined and
studied the concept of ‘exact sequences of L-modules’.Further extending the concepts in crisp theory, we have introduced the
fuzzy analogues ‘projective and injective L-modules’. We have proved many
results in this context. Further we have defined and explored notion of ‘essential
L-submodules of an L-module’. Still there are results in crisp theory related to the
topics covered in this thesis which are to be investigated in the fuzzy setting.
There are a lot of ideas still left in algebra, related to the theory of
modules, such as the ‘injective hull of a module’, ‘tensor product of modules’
etc. for which the fuzzy analogues are not defined and explored.
Description:
Department of Mathematics, Cochin University of Science and Technology
Sasidharan, Nair S; Dr.Babu, Joseph K(Cochin University of Science and Technology, 1977)
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Abstract:
The present thesis deals with some studies in molecular dynamics using spectroscopic data. Two new approximation procedures the variable method and the average bonding energy criterion have been developed for a reliable calculation of molecular force fields and applied to several molecular species belonging to the xy2 type.
Description:
Department of Physics, Cochin University of Science & Technology
Santhakumari, B; Dr.Krishna Pillai, M G(Cochin University of Science And Technology, 1976)
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Abstract:
This thesis deals with some studies in molecular mechanic using spectroscopic data. It includes an improvement in the parameter technique for the evaluation of exact force fields, the introduction of a new and simple algebraic method for the force field calculation and a study of asymmetric variation of bonding forces along a bond.
Description:
Department of physics, Cochin University of Science And Technology
Annie,Joseph Vallamattom; Dr.Krishna Pillai, M G(Cochin University of Science And Technology, November , 1978)
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Abstract:
This thesis is divided into two parts. The first part deals with some studies in molecular mechanics Using spectroscopic data and has four chapters in it. Certain approximation methods for the evaluation of molecular force fields are herein developed The second part, which consists of the last two chaptcrs, deals with infrared spectral studies of ternary liquid systems and a polymer film prepared by glow discharge method.
Description:
Department of physics, Cochin University of Science And Technology
Balakrishnan, K V; Dr.George, K K; Dr.Joseph,Francis D(Cochin University of Science and Technology, October , 1996)
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Abstract:
This thesis is essentially concerned with a study of the
recovery of pungency-free colour matter from capsicum spice
of Indian origin. A spice oleoresin may be defined as the total soluble extract of the spice in a specific solvent and embraces all the active components that contribute to aroma, taste and related sensory factors associated with the spice, together with varying amounts of pigments, plant waxes, resins and fixed oils. Whereas, in general, oleoresins are coveted for their flavour qualities, in some cases, the pigments present therein play a vital role in food technology Of these, capsicum oleoresin is the most outstanding, since it contributes both colour and flavour principles.
Description:
Department of Polymer Science and Rubber Technology
Cochin University of Science and Technology
Kuriakose, V C; Dr.Babu, Joseph K(Cochin University of Science And Technology, September , 1982)
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Abstract:
The thesis deals with certain quantum field systems exhibiting spontaneous symmetry breaking and their response to temperature. These models find application in diverse branches such as particle physics, solid state physics and non~linear optics. The nature of phase transition that these systems may undergo is also investigated. The thesis contains seven chapters. The first
chapter is introductory and gives a brief account of the various phenomena associated with spontaneous symmetry breaking. The chapter closes with anote on the effect of temperature on quantum field systems. In chapter 2, the spontaneous symmetry breaking phenomena are reviewed in more detail. Chapter 3, deals with the formulation of ordinary and generalised sine-Gordon field theories on a lattice and the study of the nature of phase transition occurring in these systems. In chapter 4, the effect of temperature on these models is studied, using the effective potential method. Chapter 5 is a continuation of this study for another model, viz, the
m6 model. The nature of phase transition is also studied. Chapters 5 and 6 constitute a report of the investigations on the behaviour of coupling constants under thermal excitation D1 $4 theory, scalar electrodynamics, abelian and non-abelian gauge theories
Description:
Department of physics, Cochin University of Science And Technology
Gopakumar, G; Dr.Kuttyamma, V J(Cochin University of Science and Technology, June 6, 1991)
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Abstract:
The work presented in this thesis is centered mainly around delineating the toxic effect of hydrogen sulphide on penaeid prawns and understand its influence on the ecology of estuary. The present investigation also involved characterization of the effects of hydrogen sulphide on the growth and behavioural responses of Penaeus indicus. The test animals employed during the present study namely indicus and Metapenaeus dobsoni are both ecologically and economically relevant. The thesis embodying the details of the investigation has been organized into three chapters comprising Acute toxicity, influence of hydrogen sulphide on the ecology of estuary and effect of hydrogen sulphide on growth and substratum selectivity of penaeid prawn. Each chapter has been partioned into various sections as Introduction, Material and Methods, Results and Discussion for a lucid presentation of the subject matter.
Description:
Division of Marine Biology
Microbiology and Biochemistry, School of Marine Science,
Cochin University of Science
and Technology
Vijayakumar,A; Dr.Thrivikraman, T(Cochin University of Science and Technology, July , 1985)
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Abstract:
This thesis is an attempt to initiate the development of a discrete geometry of the discrete
plane H = {(qmxo,qnyo); m,n e Z - the set of integers}, where q s (0,1) is fixed and (xO,yO) is a fixed point in the first quadrant of the complex plane, xo,y0 ¢ 0. The discrete plane was first considered by Harman in 1972, to evolve a discrete analytic function theory for geometric difference functions. We shall mention briefly, through various sections, the principle
of discretization, an outline of discrete a alytic function theory, the concept of geometry of space and also summary of work done in this thesis
Description:
Department
of Mathematics and Statistics,Cochin University of Science & Technology
Ramachandra, Sharma N; Dr.Madhavan Pillai, P(Cochin University of Science And Technology, March , 1988)
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Abstract:
Strychnine is the major alkaloid present in the seeds of _Strychnos, nuxvomica tree which grow naturally in this area. Strychnine has a very complex chemical structure and is known to stimulate all portions of the central nervous system with preference to the spinal cord. However, it is a powerful convulsant and death results from asphyxia. Consequently strychnine has no therapeutic application in the western system of medicine at present. The objective of this work, therefore, was to convert strychnine by microbial transformation into a product having more desirable pharmacological properties so that this locally available natural product may find some use in the preparation of a therapeutic agent.
Description:
Department of applied chemistry, Cochin University of Science And Technology