Biju Kumar, S; Dr.Mathew, K T(Cochin University of Science & Technology, March , 2002)
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Abstract:
The thesis mainly focuses on material characterization in different
environments: freely available samples taken in planar fonn, biological samples
available in small quantities and buried objects.Free space method, finds many applications
in the fields of industry, medicine and communication. As it is a non-contact
method, it can be employed for monitoring the electrical properties of materials
moving through a conveyor belt in real time. Also, measurement on such systems at
high temperature is possible. NID theory can be applied to the characterization of
thin films. Dielectric properties of thin films deposited on any dielectric substrate
can be determined. ln chemical industry, the stages of a chemical reaction can be
monitored online. Online monitoring will be more efficient as it saves time and
avoids risk of sample collection.Dielectric contrast is one of the main factors, which decides the
detectability of a system. lt could be noted that the two dielectric objects of same
dielectric constant 3.2 (s, of plastic mine) placed in a medium of dielectric constant
2.56 (er of sand) could even be detected employing the time domain analysis of the reflected signal. This type of detection finds strategic importance as it provides
solution to the problem of clearance of non-metallic mines. The demining of these
mines using the conventional techniques had been proved futile. The studies on the
detection of voids and leakage in pipes find many applications.The determined electrical properties of tissues can be used for numerical modeling
of cells, microwave imaging, SAR test etc. All these techniques need the accurate
determination of dielectric constant. ln the modem world, the use of cellular and
other wireless communication systems is booming up. At the same time people are
concemed about the hazardous effects of microwaves on living cells. The effect is
usually studied on human phantom models. The construction of the models requires
the knowledge of the dielectric parameters of the various body tissues. lt is in this
context that the present study gains significance. The case study on biological
samples shows that the properties of normal and infected body tissues are different.
Even though the change in the dielectric properties of infected samples from that of
normal one may not be a clear evidence of an ailment, it is an indication of some
disorder.ln medical field, the free space method may be adapted for imaging the
biological samples. This method can also be used in wireless technology.
Evaluation of electrical properties and attenuation of obstacles in the path of RF
waves can be done using free waves. An intelligent system for controlling the
power output or frequency depending on the feed back values of the attenuation may
be developed.The simulation employed in GPR can be extended for the exploration of the
effects due to the factors such as the different proportion of water content in the soil,
the level and roughness of the soil etc on the reflected signal. This may find
applications in geological explorations. ln the detection of mines, a state-of-the art technique for scanning and imaging an active mine field can be developed using
GPR. The probing antenna can be attached to a robotic arm capable of three degrees
of rotation and the whole detecting system can be housed in a military vehicle. In
industry, a system based on the GPR principle can be developed for monitoring
liquid or gas through a pipe, as pipe with and without the sample gives different
reflection responses. lt may also be implemented for the online monitoring of
different stages of extraction and purification of crude petroleum in a plant.Since biological samples show fluctuation in the dielectric nature with time
and other physiological conditions, more investigation in this direction should be
done. The infected cells at various stages of advancement and the normal cells
should be analysed. The results from these comparative studies can be utilized for
the detection of the onset of such diseases. Studying the properties of infected
tissues at different stages, the threshold of detectability of infected cells can be
determined.
Description:
Department of Electronics, Cochin University of Science
and Technology.
Sobha, A. P; Prof. (Dr.) Sunil K. Narayanankutty(Cochin University of Science and Technology, August , 2015)
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Abstract:
Combining intrinsically conducting polymers with carbon nanotubes
(CNT) helps in creating composites with superior electrical and thermal
characteristics. These composites are capable of replacing metals and
semiconductors as they possess unique combination of electrical conductivity,
flexibility, stretchability, softness and bio-compatibility. Their potential
for use in various organic devices such as super capacitors, printable
conductors, optoelectronic devices, sensors, actuators, electrochemical
devices, electromagnetic interference shielding, field effect transistors,
LEDs, thermoelectrics etc. makes them excellent substitutes for present day
semiconductors.However, many of these potential applications have not been fully
exploited because of various open–ended challenges. Composites meant for
use in organic devices require highly stable conductivity for the longevity of
the devices. CNT when incorporated at specific proportions, and with
special methods contributes quite positively to this end.The increasing demand for energy and depleting fossil fuel reserves
has broadened the scope for research into alternative energy sources. A
unique and efficient method for harnessing energy is thermoelectric energy
conversion method. Here, heat is converted directly into electricity using a
class of materials known as thermoelectric materials. Though polymers have
low electrical conductivity and thermo power, their low thermal conductivity
favours use as a thermoelectric material. The thermally disconnected, but
electrically connected carrier pathways in CNT/Polymer composites can satisfy the so-called “phonon-glass/electron-crystal” property required for
thermoelectric materials.
Strain sensing is commonly used for monitoring in engineering,
medicine, space or ocean research. Polymeric composites are ideal candidates
for the manufacture of strain sensors. Conducting elastomeric composites
containing CNT are widely used for this application. These CNT/Polymer
composites offer resistance change over a large strain range due to the low
Young‟s modulus and higher elasticity. They are also capable of covering
surfaces with arbitrary curvatures.Due to the high operating frequency and bandwidth of electronic
equipments electromagnetic interference (EMI) has attained the tag of an
„environmental pollutant‟, affecting other electronic devices as well as
living organisms. Among the EMI shielding materials, polymer composites
based on carbon nanotubes show great promise. High strength and stiffness,
extremely high aspect ratio, and good electrical conductivity of CNT make
it a filler of choice for shielding applications. A method for better dispersion,
orientation and connectivity of the CNT in polymer matrix is required to
enhance conductivity and EMI shielding.
This thesis presents a detailed study on the synthesis of functionalised
multiwalled carbon nanotube/polyaniline composites and their application
in electronic devices. The major areas focused include DC conductivity
retention at high temperature, thermoelectric, strain sensing and electromagnetic
interference shielding properties, thermogravimetric, dynamic mechanical
and tensile analysis in addition to structural and morphological studies.
Bindiya, Varghese M; Dr.Poulose Jacob, K; Dr.Unnikrishnan, A(Cochin University of Science And Technology, June 7, 2013)
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Abstract:
Knowledge discovery in databases is the non-trivial process of identifying valid, novel potentially useful and ultimately understandable patterns from data. The term Data mining refers to the process which does the exploratory analysis on the data and builds some model on the data. To infer patterns from data, data mining involves different approaches like association rule mining, classification techniques or clustering techniques. Among the many data mining techniques, clustering plays a major role, since it helps to group the related data for assessing properties and drawing conclusions. Most of the clustering algorithms act on a dataset with uniform format, since the similarity or dissimilarity between the data points is a significant factor in finding out the clusters. If a dataset consists of mixed attributes, i.e. a combination of numerical and categorical variables, a preferred approach is to convert different formats into a uniform format. The research study explores the various techniques to convert the mixed data sets to a numerical equivalent, so as to make it equipped for applying the statistical and similar algorithms. The results of clustering mixed category data after conversion to numeric data type have been demonstrated using a crime data set. The thesis also proposes an extension to the well known algorithm for handling mixed data types, to deal with data sets having only categorical data. The proposed conversion has been validated on a data set corresponding to breast cancer. Moreover, another issue with the clustering process is the visualization of output. Different geometric techniques like scatter plot, or projection plots are available, but none of the techniques display the result projecting the whole database but rather demonstrate attribute-pair wise analysis
Description:
Department of Computer Science
Cochin University of Science and Technology
Jayesh, P; Dr.Bright Singh,I S(Cochin University of Science and Technology, September , 2012)
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Abstract:
Unveiling the molecular and regulatory mechanisms that prevent in vitro
transformation in shrimp remains elusive in the development of continuous cell
lines, with an arduous history of over 25 years (Jayesh et al., 2012). Despite
presenting challenges to researchers in developing a cell line, the billion dollar
aquaculture industry is under viral threat. In addition, the regulatory mechanisms
that prevent in vitro transformation and carcinoma in shrimps might provide new
leads for the development of anti-ageing and anti-cancer interventions in human
(Vogt, 2011) and in higher vertebrates. This highlights the importance of
developing shrimp cell lines, to bring out effective prophylactics against shrimp
viruses and for understanding the mechanism that induce cancer and ageing in
human.. Advances in molecular biology and various gene transfer technologies for
immortalization of cells have resulted in the development of hundreds of cell lines
from insects and mammals, but yet not a single cell line has been developed from
shrimp and other marine invertebrates. With this backdrop, the research described
in this thesis attempted to develop molecular tools for induced in vitro
transformation in lymphoid cells from Penaeus monodon and for the development
of continuous cell lines using conventional and novel technologies to address the
problems at cellular and molecular level.
Description:
National Centre for Aquatic Animal
Health, School of Environmental Studies, Cochin University of Science and
Technology
Sobhana, Mathew; Dr.Girish Kumar, K(Cochin University of Science and Technology, March , 2012)
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Abstract:
Electroanalytical techniques represent a class of powerful and versatile
analytical method which is based on the electrical properties of a solution of
the analyte when it is made part of an electrochemical cell. They offer high
sensitivity, accuracy, precision and a large linear dynamic range. The cost of
instrumentation is relatively low compared to other instrumental methods of
analysis. Many solid state electrochemical sensors have been commercialised
nowadays. Potentiometry is a very simple electroanalytical technique with
extraordinary analytical capabilities. Since valinomycin was introduced as an
ionophore for K+, Ion Selective Electrodes have become one of the best
studied and understood analytical devices. It can be used for the
determination of substances ranging from simple inorganic ions to complex
organic molecules. It is a very attractive option owing to the wide range of
applications and ease of the use of the instruments employed. They also
possess the advantages of short response time, high selectivity and very low
detection limits. Moreover, analysis by these electrodes is non-destructive and
adaptable to small sample volumes. It has become a standard technique for
medical researchers, biologists, geologists and environmental specialists.
This thesis presents the synthesis and characterisation of five
ionophores. Based on these ionophores, nine potentiometric sensors are
fabricated for the determination of ions such as Pb2+, Mn2+, Ni2+, Cu2+ and
Sal- ion (Salicylate ion). The electrochemical characterisation and analytical
application studies of the developed sensors are also described. The thesis is
divided into eight chapters
Description:
Department of Applied Chemistry, Cochin University of Science and Technology
Manju, N J; Dr.Bright Singh,I S(Cochin University of Science and Technology, October , 2007)
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Abstract:
This thesis entitled Development of nitrifying ans photosynthetic sulfur bacteria based bioaugmentation systems for the bioremediation of ammonia and hydregen sulphide in shrimp culture.
the thesis is to propose a sustainable, low cost option for the mitigation of toxic ammonia and hydrogen sulphide in shrimp culture systems. Use of ‘bioaugmentors’ as pond additives is an emerging field in aquaculture. Understanding the role of organisms involved in the ‘bioaugmentor’ will obviously help to optimize conditions for their activity.The thesis describes the use of wood powder immobilization of nitrifying consortia.Shrimp grow out systems are specialized and highly dynamic aquaculture production units which when operated under zero exchange mode require bioremediation of ammonia, nitrite nitrogen and hydrogen sulphide to protect the crop. The research conducted here is to develop an economically viable and user friendly technology for addressing the above problem. The nitrifying bacterial consortia (NBC) generated earlier (Achuthan et al., 2006) were used for developing the technology.Clear demonstration of better quality of immobilized nitrifiers generated in this study for field application.
Description:
National Centre for Aquatic Animal Health, School of Environmental
Studies, Cochin University of Science and Technology
Jaya, V.L; Dr Gopika Kumari(Cochin University of Science and Technology, May 20, 2015)
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Abstract:
Digital Image Processing is a rapidly evolving eld with growing applications
in Science and Engineering. It involves changing the nature
of an image in order to either improve its pictorial information
for human interpretation or render it more suitable for autonomous
machine perception. One of the major areas of image processing
for human vision applications is image enhancement. The principal
goal of image enhancement is to improve visual quality of an image,
typically by taking advantage of the response of human visual
system.
Image enhancement methods are carried out usually in the pixel
domain. Transform domain methods can often provide another way
to interpret and understand image contents. A suitable transform,
thus selected, should have less computational complexity. Sequency
ordered arrangement of unique MRT (Mapped Real Transform)
coe cients can give rise to an integer-to-integer transform, named
Sequency based unique MRT (SMRT), suitable for image processing
applications. The development of the SMRT from UMRT (Unique
MRT), forward & inverse SMRT algorithms and the basis functions
are introduced. A few properties of the SMRT are explored and its
scope in lossless text compression is presented.
Neetha,John; Dr.Rani,Joseph(Cochin University of Science and Technology, December 30, 1998)
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Abstract:
Novel latex based and solution based adhesives were prepared and evaluated for wood to wood bonding.These adhesive were found to be superior to commercical adhesives like fevicol and dentrite.Novel adhesives were prepared for leather to leather bonding and these were also found to be more efficientt than the polyurethane type and dentrite adhesives used commercially.A novel strip adhesive system employing very low amount of solvents was tried successfully for rubber-to-metal bonding.Further ,a novel adhesive system was investigated successfully for bonding copper coated bead wire and steel cord to rubber by modifying it with chloroprene rubber.
Description:
Department of Polymer Science and Rubber Technology, Cochin
University of Science and Technology
Suma, K K; Dr.Rani,Joseph(Cochin University of Science and Technology, July , 2009)
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Abstract:
The present study describes the preparation of Vinyl acetate-Butyl
acrylate copolymer lattices of varying compositions and solid contents by
semicontinuous emulsion polymerization method. This copolymer lattices were
used as binder to develop a new surface coating formulation. The properties of
this surface coating were improved by using nano TiO2 colloidal sol as a
pigment. Antimicrobial activity of surface coatings was improved by the
addition of carboxymethyl chitosan as biocide. Uniformly dispersed tyre crumb
was used to give a mat finish to the coating. The mechanical properties adhesive
properties, thermal properties etc. of the coatings are presented in thesis.
Description:
Dept. of Polymer Science and Rubber Technology,
Cochin University of Science and technology
Benjamin Varghese, P; Dr.Madhusoodanan, K N(Cochin University Of Science And Technology, February 15, 2013)
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Abstract:
The objective of the preset work is to develop optical fiber
sensors for various physical and chemical parameters. As a part of this
we initially investigated trace analysis of silica, ammonia, iron and
phosphate in water. For this purpose the author has implemented a dual
wavelength probing scheme which has many advantages over
conventional evanescent wave sensors. Dual wavelength probing
makes the design more reliable and repeatable and this design makes
the sensor employable for concentration, chemical content,
adulteration level, monitoring and control in industries or any such
needy environments. Use of low cost components makes the system
cost effective and simple. The Dual wavelength probing scheme is
employed for the trace analysis of silica, iron, phosphate, and
ammonia in water. Such sensors can be employed for the steam and
water quality analysers in power plants. Few samples from a power
plant are collected and checked the performance of developed system
for practical applications.
Description:
Department of Instrumentation,
Cochin University of Science and Technology