Rathna Kala, R; Dr.Chandrika, V(Cochin University of Science and Technology, 2000)
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Abstract:
The present study on "Microbial production of antibiotics from mangrove ecosystem” was carried out for a period of one year in four selected Stations, Mangalavana, Narakkal, Puthuvyppu and light house area of Puthuvyppu (9°55' — 10°10'N and 76°10‘ - 76°20'E) from January to December 1991. Though much emphasis has been given to occurrence and distribution of actinomycetes, an attempt was also made to understand the distribution patterns of other micro flora in the sediments. Data on physico-chemical parameters were also collected to find out their relationship if any with the microflora. The principle interest of the present investigation is to determineseasonal variations of antagonistic actinomycetes in selected mangrove ecosystem. The microbial interrelationship in mangrove sediments was found out by constructing the ratio between bacteria and actinomycetes, bacteria and fungi, fungi and actinomycetes. In addition temperature, pH, salinity, dissolved oxygen and organic carbon were determined seasonally and their possible relationship was statistically analyzed and the results are presented. Isolated actinomycetes were subjected to cross streak assay to know their nature of antibiotic activity against test fish pathogens and crude antibiotics were extracted from selected isolates and their inhibitory activity is studied and the results are discussed.
Jayachandran, K; Dr.Chandrasekaran,M(Cochin University of Science And Technology, August 28, 1998)
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Abstract:
Many of the existing methods for the treatment of rubber latex centrifugation
eflluent are not only unsatisfactory in their efliciency to effect near perfect treatment in
bringing down the COD to optimum level, but also time consuming and need a large
landspace. As the rate of effluent generation is extremely high (20 litres for kilogram of
rubber) there is a need for development of efficient system,capable of rapid reduction of
COD and BOD.
Though the organic load of the rubber efiluent is very high, it does not contain
much processed chemicals and therefore it can be considered as a ‘biological eflluent’.
Further, the ratio of the Chemical Oxygen Demand to Biological Oxygen Demand
(COD/BOD) of this effluent remain almost as a constant value. According to
Montgomery (1967), estimation of BOD is not ideally suited for studies on process
design, treatability, control of treatment plants, setting standards for treated effluents and
assessing the effect of polluting discharges on the oxygen resources of receiving waters.
Hence in the present study COD was measured to determine the impact of treatment
system on the effluent.
In the present study, attempts were made to evaluate the efficiencies of certain
methods such as packed bed reactor using immobilized microbial cells, rotating biological
contactor (RBC) and activated sludge process, for rapid and efficient treatment of
natural rubber latex centrifugation effluent. In addition, studies were also carn'ed out to develop a suitable bioprocess for the coagulation of skim latex, as an alternative to the
presently used acid coagulation process towards reducing the pollution load, besides
recovering quality rubber
Description:
Department of Biotechnology, Cochin
University of Science and Technology
Lathika Cicily, Thomas; Bijoy Nandan, S(Cochin University of Science And Technology, February , 2015)
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Abstract:
The overall attempt of the study was aimed to understand the
microphytoplankton community composition and its variations along a highly
complex and dynamic marine ecosystem, the northern Arabian Sea. The data
generated provides a first of its kind knowledge on the major primary
producers of the region. There appears significant response among the
microphytoplankton community structure towards the variations in the
hydrographic conditions during the winter monsoon period. Interannually,
variations were observed within the microphytoplankton community associated
with the variability in temperature patterns and the intensity of convective
mixing. Changing bloom pattern and dominating species among the
phytoplankton community open new frontiers and vistas towards more intense
study on the biological responses towards physical processes. The production
of large amount of organic matter as a result of intense blooming of Noctiluca
as well as diatoms aggregations augment the particulate organic substances in
these ecosystem. This definitely influences the carbon dynamics of the
northern Arabian Sea. Detailed investigations based on time series as well as
trophodynamic studies are necessary to elucidate the carbon flux and
associated impacts of winter-spring blooms in NEAS. Arabian sea is
considered as one among the hotspot for carbon dynamics and the pioneering
records on the major primary producers fuels carbon based export production
studies and provides a platform for future research. Moreover upcoming
researches based on satellite based remote sensing on productivity patterns
utilizes these insitu observations and taxonomic data sets of phytoplankton for
validation of bloom specific algorithm development and its implementation.
Furthermore Saurashtra coast is considered as a major fishing zone of Indian
EEZ. The studies on the phytoplankton in these regions provide valuable raw
data for fishery prediction models and identifying fishing zones. With the
Summary and Conclusion
177
baseline data obtained further trophodynamic studies can be initiated in the
complex productive North Eastern Arabian Seas (NEAS) ecosystem that is still
remaining unexplored.
Subin Thomas; Dr. K. Rajeev Kumar(Cochin University of Science and Technology, November 11, 2015)
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Abstract:
The semiconductor industry's urge towards faster, smaller and cheaper
integrated circuits has lead the industry to smaller node devices. The integrated
circuits that are now under volume production belong to 22 nm
and 14 nm technology nodes. In 2007 the 45 nm technology came with
the revolutionary high- /metal gate structure. 22 nm technology utilizes
fully depleted tri-gate transistor structure. The 14 nm technology is a
continuation of the 22 nm technology. Intel is using second generation
tri-gate technology in 14 nm devices. After 14 nm, the semiconductor industry
is expected to continue the scaling with 10 nm devices followed by
7 nm. Recently, IBM has announced successful production of 7 nm node
test chips. This is the fashion how nanoelectronics industry is proceeding
with its scaling trend.
For the present node of technologies selective deposition and selective removal
of the materials are required. Atomic layer deposition and the
atomic layer etching are the respective techniques used for selective deposition
and selective removal. Atomic layer deposition still remains as
a futuristic manufacturing approach that deposits materials and lms in
exact places. In addition to the nano/microelectronics industry, ALD is
also widening its application areas and acceptance. The usage of ALD
equipments in industry exhibits a diversi cation trend. With this trend,
large area, batch processing, particle ALD and plasma enhanced like ALD
equipments are becoming prominent in industrial applications. In this
work, the development of an atomic layer deposition tool with microwave
plasma capability is described, which is a ordable even for lightly funded
research labs.
Terry Mechado; Dr.Seralathan, P(Cochin University Of Science And Technology, April 12, 1995)
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Abstract:
Continental shelf is of particular significance in marine geology ,
because it links the two basically different structural zones in the earth's crust; the
continents and ocean basins. The shelf area has much wider importance in many
fields of activity such as scientific, economic, social, political and strategic. The
pace of development has ultimately put pressure on mankind to look for exploitable
resources and accessibility to the continental shelf area and beyond. Added to the
above, the developmental activities in the coastal area would readily and directly
influence the innershelf sediments. This situation demands a thorough geological
knowledge of the continental shelf area. Moreover, a successful management of
the continental shelf zone requires an optimum data base on the physico-chemical
nature of the shelf sediments. Although sedimentological studies were carried out
along the western continental shelf of India, a well documented systematic study
of the inner shelf off Trivandrum coast is still found to be lacking. Considering the
physiographic settings and the vicinity of two renowned placer deposits at Chavara
and Manavalakurichi, such a sedimetological inventory has become all the more
vital.
In view of the above, a research programme has been drawn up to
account the salient sedimentological and mineralogical aspects of the innershelf
and beach sediments between Paravur and Kovalam, Trivandrum district, Kerala
(latitudes 8° 7'00" to 8° 47'45" and longitudes 76°43'00" to 77° 40'45"). The
findings are presented in six chapters formatted to address the aim of this
research.
Description:
Marine Geology Division
School of Marine Sciences
Cochin University of Science And Technology
Maheswaran, P A; Revichandran, C(NATIONAL INSTITUTE OF OCEANOGRAPHY, August , 2004)
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Abstract:
In this thesis, a detailed attempt has been made to understand the general hydrography of the upper 300m of the water column, in the eastern Arabian Sea and the western Bay of Bengal, the two contrasting basins in the northern Indian Ocean, using recently collected data sets of Marine Research-Living Resources (MR-LR) assessment programme, funded by Department of Ocean Development, from various cruises, pertaining to different seasons. Initially it discuss the general hydrography of the west and east coasts of India are covered, in the context of mixed layer processes. The study describes the materials and methods . To compare the hydrography of the AS and BOB, a unique MLD(Mixed Layer Depth) definition for AS and BOB is essential, for which the 275 CTD profiles were used. A comparison has been made among the various MLD criteria with the actual MLD.
The monthly evolution of MLD, barrier layer thickness and the role of atmospheric forcing on the dynamics of the mixed layer in the AS and BOB were studied. The general hydrography along the west coast of India is described. The upwelling/downwelling, winter cooling processes, in the context of chemical and biological parameters, are also addressed. Finally the general hydrography of the Bay of Bengal is covered. The most striking feature in the hydrography are the signature of an anticyclonic subtropical gyre during spring intermonsoon and a cold core eddy during winter monsoon. The TTS(Typical Tropical Structure) of the euphotic layer was also investigated.
Manoj, Joseph; Dr.Mohanan, P(Cochin University of Science & Technology, October , 2010)
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Abstract:
The thesis is the outcome of the theoretical and experimental investigations on mocrostrip-fed printed strip monopole antenna.Finite ground plane has been effectively utilized to excite a new resonance near the fundamental mode by introducing another extended strip from the ground plane,without affecting compactness.Further size reduction was achieved by carrying out folding analysis on dual strip antenna and a compact folded dual strip antenna has been designed.Design methodologies for both the compact dual band antennas are presented.The proposed antennas can be used for mobile and WLAN applications due to wide bandwidth,moderate gain and omnidirectional radiation coverage.
Description:
Department of
Electronics, Cochin University of Science and Technology.
Sreedevi, E P; Dr.Sankaran, P G(Cochin University Of Science And Technology, April 9, 2010)
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Abstract:
there has been much research
on analyzing various forms of competing risks data. Nevertheless, there are several
occasions in survival studies, where the existing models and methodologies are
inadequate for the analysis competing risks data. ldentifiabilty problem and various
types of and censoring induce more complications in the analysis of competing risks
data than in classical survival analysis. Parametric models are not adequate for the
analysis of competing risks data since the assumptions about the underlying lifetime
distributions may not hold well. Motivated by this, in the present study. we develop
some new inference procedures, which are completely distribution free for the
analysis of competing risks data.
Description:
Department of Statistics, Cochin University of Science and
Technology
Hareesh, G; Dr.Balakrishna, N(Cochin University of Science and Technology, August , 2010)
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Abstract:
The thesis has covered various aspects of modeling and analysis of finite mean time series
with symmetric stable distributed innovations. Time series analysis based on Box and
Jenkins methods are the most popular approaches where the models are linear and errors
are Gaussian. We highlighted the limitations of classical time series analysis tools and
explored some generalized tools and organized the approach parallel to the classical set up.
In the present thesis we mainly studied the estimation and prediction of signal plus noise
model. Here we assumed the signal and noise follow some models with symmetric stable
innovations.We start the thesis with some motivating examples and application areas of alpha stable
time series models. Classical time series analysis and corresponding theories based on finite
variance models are extensively discussed in second chapter. We also surveyed the existing
theories and methods correspond to infinite variance models in the same chapter.
We present a linear filtering method for computing the filter weights assigned to the observation
for estimating unobserved signal under general noisy environment in third chapter.
Here we consider both the signal and the noise as stationary processes with infinite variance
innovations. We derived semi infinite, double infinite and asymmetric signal extraction filters
based on minimum dispersion criteria. Finite length filters based on Kalman-Levy
filters are developed and identified the pattern of the filter weights. Simulation studies show that the proposed methods are competent enough in signal extraction for processes
with infinite variance.Parameter estimation of autoregressive signals observed in a symmetric stable noise
environment is discussed in fourth chapter. Here we used higher order Yule-Walker type
estimation using auto-covariation function and exemplify the methods by simulation and
application to Sea surface temperature data. We increased the number of Yule-Walker
equations and proposed a ordinary least square estimate to the autoregressive parameters.
Singularity problem of the auto-covariation matrix is addressed and derived a modified
version of the Generalized Yule-Walker method using singular value decomposition.In fifth chapter of the thesis we introduced partial covariation function as a tool for stable
time series analysis where covariance or partial covariance is ill defined. Asymptotic results
of the partial auto-covariation is studied and its application in model identification of stable
auto-regressive models are discussed. We generalize the Durbin-Levinson algorithm to
include infinite variance models in terms of partial auto-covariation function and introduce
a new information criteria for consistent order estimation of stable autoregressive model.In chapter six we explore the application of the techniques discussed in the previous
chapter in signal processing. Frequency estimation of sinusoidal signal observed in symmetric
stable noisy environment is discussed in this context. Here we introduced a parametric
spectrum analysis and frequency estimate using power transfer function. Estimate of the
power transfer function is obtained using the modified generalized Yule-Walker approach.
Another important problem in statistical signal processing is to identify the number of
sinusoidal components in an observed signal. We used a modified version of the proposed
information criteria for this purpose.
Description:
Department of Statistics,
Cochin University of Science and Technology