Sony, George; Dr.V P N Nampoori(Cochin University of Science & Technology, September , 2011)
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Abstract:
The present thesis report the results obtained from the studies carried out on the
laser blow off plasma (LBO) from LiF-C (Lithium Fluoride with Carbon) thin film
target, which is of particular importance in Tokamak plasma diagnostics. Keeping
in view of its significance, plasma generated by the irradiation of thin film target by
nanosecond laser pulses from an Nd:YAG laser over the thin film target has been
characterized by fast photography using intensified CCD. In comparison to other
diagnostic techniques, imaging studies provide better understanding of plasma
geometry (size, shape, divergence etc) and structural formations inside the plume
during different stages of expansion.
Description:
International School of Photonics,Cochin University of Science and Technology
Mary, Alexander; Dr. Eby Thomas, Thachil(Cochin University of Science & Technology, April , 2008)
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Abstract:
This research project explores the utilization of cardanol in various capacities for
rubber processing. Cardanol is a phenol with a long side chain in the meta position
of the benzene ring. It is obtained by the vacuum distillation of cashew Hut shell
liquid (CNSL) which is a cheap agro-byproduct. In this study, the plasticizer property
of cardanol was investigated in silica filled and HAF black filled NR, NBR, EPDM
and CR by comparing cure characteristics and mechanical properties of vulcanizates
containing conventional plasticizer with those containing cardanol as plasticizer. The
co-activator, antioxidant and accelerator properties were investigated in gum samples
of NR, NBR, EPDM and CR by comparing the properties of vulcanizates which
contain conventional co-activator, antioxidant and accelerator with those in which
each of them was replaced by cardanol. The general effectiveness of cardanol was
investigated by determination of cure time , measurement of physical and
mechanical properties, ageing studies, crosslink density, extractability, FTIR spectra,
TGA etc.The results show that cardanol can be a substitute for aromatic oil in both silica filled
and HAF black filled NR. Again, it can replace dioctyl phthalate in both silica filled
and HAF black filled NBR. Similarly, cardanol Can replace naphthenic oil in silica
filled as well as HAF black filled EPDM and CR. The cure characteristics and
mechanical properties are comparable in all the eight cases. The co-activator
property of cardanol is comparable to stearic acid in all the four rubbers. The cure
characteristics and mechanical properties in this case are also comparable. The
antioxidant ,property of cardanol is comparable to TQ in all the four rubbers. The
antioxidant property of cardanol is comparable to TQ in all the four case of NBR and
EPDM.The
accelerator property of cardarlol is comparable with CBS in the case of NBR and
EPDM. No accelerator property is observed in the case of NR. The accelerator
property of cardanol in CR is not negligible when compared with TMTD.
Description:
Department of Polymer Science and Rubber Technology,
Cochin University of Science and Technology
Anupam,Chandran R; Dr.Aanandan, C K(Cochin University of Science and Technology, June , 2007)
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Abstract:
This thesis presents the Radar Cross Section measurements of different geometric structures such as flat plate,cylinder, corner reflector and circular cone loaded with fractal based metallo dielectric structures.Use of different fractal geometris,metallizations of different shapes as well as the frequency tanability is investigated for TE and TM polarization of the incident electromagnetic field.Application of fractal based metallo-dielectric structures results in RCS reduction over a wide range of frequency bands.RCS enhancement of dihedral corner is observed at certain acute and obtuse corner angles.The experimental results are validated using electromagnetic simulation softwares.
Description:
Department of Electronics,
Cochin University of Science and Technology
Ravindranathan, S; Dr.Unnikrishnan, A(Cochin University of Science & Technology, October , 1991)
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Abstract:
Neural Network has emerged as the topic of the day.
The spectrum of its application is as wide as from ECG noise
filtering to seismic data analysis and from elementary
particle detection to electronic music composition. The
focal point of the proposed work is an application of a
massively parallel connectionist model network for detection
of a sonar target. This task is segmented into: (i) generation of training patterns from sea noise that
contains radiated noise of a target, for teaching the
network;(ii) selection of suitable network topology and learning
algorithm and (iii) training of the network and its subsequent testing
where the network detects, in unknown patterns applied
to it, the presence of the features it has already
learned in. A three-layer perceptron using backpropagation
learning is initially subjected to a recursive training
with example patterns (derived from sea ambient noise with
and without the radiated noise of a target). On every
presentation, the error in the output of the network is
propagated back and the weights and the bias associated with
each neuron in the network are modified in proportion to
this error measure. During this iterative process, the network converges and extracts the target features which get
encoded into its generalized weights and biases.In every unknown pattern that the converged
network subsequently confronts with, it searches for the
features already learned and outputs an indication for their
presence or absence. This capability for target detection is
exhibited by the response of the network to various test
patterns presented to it.Three network topologies are tried with two
variants of backpropagation learning and a grading of the
performance of each combination is subsequently made.
Description:
Department of Electronics, Cochin University of Science and Technology
James, Kurian; Dr.Saseendran Pillai,P R(Cochin University of Science & Technology, October , 2008)
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Abstract:
ACCURATE sensing of vehicle position and attitude is still a very challenging
problem in many mobile robot applications. The mobile robot vehicle applications
must have some means of estimating where they are and in which direction they are
heading. Many existing indoor positioning systems are limited in workspace and
robustness because they require clear lines-of-sight or do not provide absolute, driftfree
measurements.The research work presented in this dissertation provides a new approach to
position and attitude sensing system designed specifically to meet the challenges of
operation in a realistic, cluttered indoor environment, such as that of an office
building, hospital, industrial or warehouse. This is accomplished by an innovative
assembly of infrared LED source that restricts the spreading of the light intensity
distribution confined to a sheet of light and is encoded with localization and traffic
information. This Digital Infrared Sheet of Light Beacon (DISLiB) developed for
mobile robot is a high resolution absolute localization system which is simple, fast,
accurate and robust, without much of computational burden or significant processing.
Most of the available beacon's performance in corridors and narrow passages are not
satisfactory, whereas the performance of DISLiB is very encouraging in such
situations. This research overcomes most of the inherent limitations of existing
systems.The work further examines the odometric localization errors caused by over
count readings of an optical encoder based odometric system in a mobile robot due to
wheel-slippage and terrain irregularities. A simple and efficient method is investigated and realized using an FPGA for reducing the errors. The detection and correction is
based on redundant encoder measurements. The method suggested relies on the fact
that the wheel slippage or terrain irregularities cause more count readings from the
encoder than what corresponds to the actual distance travelled by the vehicle.The application of encoded Digital Infrared Sheet of Light Beacon (DISLiB)
system can be extended to intelligent control of the public transportation system. The
system is capable of receiving traffic status input through a GSM (Global System
Mobile) modem. The vehicles have infrared receivers and processors capable of
decoding the information, and generating the audio and video messages to assist the
driver. The thesis further examines the usefulness of the technique to assist the
movement of differently-able (blind) persons in indoor or outdoor premises of his
residence.The work addressed in this thesis suggests a new way forward in the
development of autonomous robotics and guidance systems. However, this work can
be easily extended to many other challenging domains, as well.
Description:
Department of Electronics,
Cochin University of Science and Technology
Suresh, Kumar M K; Dr.Chandrasekaran,M(Cochin University of Science And Technology, September , 1999)
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Abstract:
Cochin, commercial capital of Kerala, located on the west-coast of South India
has a large number of chemical and sea food industries. Earlier studies in the past
indicated that these industries contribute to heavy metal pollution, particularly mercury,
copper, and cadmium, in Cochin backwater. Hence, in the present study, it was desired
to isolate cadmium resistant bacteria from effluent discharged by chemical industry with
a view to develop an ideal bioremediation process for safe discharge of industrial
effluent in to the nearby aquatic environment.
Effluent from three industries, located in the industrial belt of Cochin, were
collected from the discharge point and cadmium resistant bacteria were screened using
standard microbiological techniques
Description:
Department of Biotechnology, Cochin University of Science and Technology
Roselin, Alex; Dr.Chandrasekaran,M(Cochin University Of Science And Technology, November 29, 2012)
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Abstract:
There exists a need for potential microorganism that could
facilitate effective bioremediation of crude oil pollutants in the
environment. Hence it was desired to isolate a potential bacterium from
marine sediment, which often experiences oil pollution and develop a
bioprocess for crude oil biodegradation. In the present study the sediment
deposits in the beach of Munakkal, Trichur dist, Kerala, collected
immediately after the major event Tsunami in 2004 was collected and
analyzed by enrichment culture technique towards isolation of potential
strains that could degrade crude oil and its fractions. From the results
obtained it was found that the sediment deposits harbor several bacteria
with potential for degrading hydrocarbons. However, among the strains
obtained, isolate no. BTTS 10 showed capabilities for utilizing both
alkanes and aromatic hydrocarbons and hence the same was selected for
further studies.
Description:
Department of Biotechnology, Cochin
University of Science and Technology
Vidya,G; Dr.Rani,Joseph; Dr.Prathapan, S; Dr.Nampoori,V P N(Cochin University Of Science And Technology, October , 2012)
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Abstract:
Light emitting polymers (LEPs) are considered as the second
generation of conducting polymers. A Prototype LEP device based on
electroluminescence emission of poly(p-phenylenevinylene) (PPV) was first
assembled in 1990. LEPs have progressed tremendously over the past 20
years. The development of new LEP derivatives are important because
polymer light emitting diodes (PLEDs) can be used for the manufacture of
next-generation displays and other optoelectronic applications such as lasers,
photovoltaic cells and sensors. Under this circumstance, it is important to
understand thermal, structural, morphological, electrochemical and
photophysical characteristics of luminescent polymers. In this thesis the author
synthesizes a series of light emitting polymers that can emit three primary
colors (RGB) with high efficiency
Description:
Department of Polymer Science and Rubber Technology
Cochin University of Science and Technology
Bybi, P C; Dr.Mohanan, P(Cochin University of Science & Technology, January , 2009)
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Abstract:
The Present thesis deals with the numerical as well as experimental investigations conducted on the resonance and radiation characteristics of Drum shaped monopole antenna, Funnel shaped monopole antenna and the shorted coplanar antenna.An introduction to the over view of antennas, state of the art planar antenna technologies, different feeding techniques and introduction of coplanar waveguides have been discussed.
Description:
Department of Electronics, Cochin University of Science and Technology
Sivaprasad, P.; Prof. (Dr). C. A. Babu(Cochin University of Science and Technology, May 3, 2015)
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Abstract:
The aerosols in the atmosphere play major role in the radiation balance of the Earthatmosphere
system. Direct and indirect impact of aerosols on the weather and climate still
remains as a topic to be investigated in detail. The effect of aerosols on the radiation budget and
thereby circulation pattern is important and requires further study. A detailed analysis of the
aerosol properties, their variability and meteorological processes that affect the aerosol
properties and distribution over the Indian region is performed in the thesis. The doctoral thesis
entitled “Characteristics of aerosols over the Indian region and their variability associated
with atmospheric conditions” contains 7 chapters. This thesis presents results on the analysis
on the distribution (spatial and temporal) and characteristics of the aerosols over the Indian
region and adjoining seas. Regional and stationwise data were analysed and methods such as
modeling and statistical analysis are implemented to understand the aerosol properties,
classification and transportation.
Chapter-1 presents a brief introduction on the aerosols, their measurement techniques,
impact of aerosols on the atmospheric radiation budget, climatic and geographic features of the
study area and the literature review on the previous studies. It provides a basic understanding in
the field of study and objective of the thesis. Definition of the aerosols, their sources/sinks and
classification of the particles according to optical and microphysical properties are described.
Different measurement techniques such as sampling and remote sensing methods are explained
in detail. Physical parameters used to describe aerosol properties and effect of aerosols on the
radiation distribution are also discussed. The chapter also explains the objectives of the thesis
and description of climatic features of the study area.
Dann, V J; Dr.Nampoori,V P N; Dr.Nandakumaran,V M(Cochin University of Science & Technology, October , 2008)
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Abstract:
Laser induced plasma (LIP) emissions from some metal oxide targets were
studied with corresponding metal targets of pure quality as a reference. Atomic emissions
in the visible region were used in the spectroscopic procedures of LIP characterization.
The studies were meant to throw light into LIP dynamics and they provided many
experimental results which improved the general awareness of plasma state.When target materials were photo-ablated with an energetically suitable laser
pulse, they developed electric charges in them.An electrical signal which was delivered
from the target served as an alternative probe signal for the diagnostics of LIP and to
track different charged states in the plasma. The signal showed a double peak distribution
with positive polarity and a modified time of flight with various voltage levels of a given
polarity.The expansion dynamics of LIP in magnetic field were also investigated
by monitoring the voltage transients generated at the target.
Description:
International School of Photonics,
Cochin University of Science and Technology
Achamma, Kurian; Dr.Nampoori,V P N(Cochin University of Science & Technology, July , 2002)
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Abstract:
The subject of Photonics is concerned with the generation,control and utilization of photons for performing a variety of tasks.It came to existence as a consequence of the harmonious fusion of optical methods with electronic technology.Wide spread use of laser based methods in electronics is slowly replacing elecrtons with photons in the field of Communication,Control and Computing .Therefore,there is a need to promote the R & D activities in the area of Photonics and to generate well trained manpower in laser related fields.Development and characterization of photonic materials is an important subject of research in the field of Photonics.Optical and thermal characterization of photonic materials using thermal lens technique is a PhD thesis in the field of Photonics in which the author describes how thermal lens effect can be used to characterize themal and optical properties of photonic materials.Plausibility of thermal lens based logic gates is also presented in this thesis.
Description:
International School of Photonics,
Cochin University of SCience and Technology