Jayaprakash, N S; Bright Singh, I S(School of Environmental Studies, 2005)
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Abstract:
The main objective of the work undertaken here was to develop an appropriate microbial technology to protect the larvae of M.rosenbergii in hatchery from vibriosis. This technology precisely is consisted of a rapid detection system of vibrios and effective antagonistic probiotics for the management of vibrios. The present work was undertaken with the realizations that to stabilize the production process of commercial hatcheries an appropriate, comprehensive and fool proof technology is required primarily for the rapid detection of Vibrio and subsequently for its management. Nine species of Vibrio have been found to be associated with larvae of M. rosenbergii in hatchery. Haemolytic assay of the Vibrio and Aeromonas on prawn blood agar showed that all isolates of V. alginolyticus and Aeromonas sp., from moribund, necrotized larve were haemolytic and the isolates of V.cholerae, V.splendidus II, V.proteolyticus and V.fluvialis from the larvae obtained from apparently healthy larval rearing systems were non-haemolytic.
Hydrolytic enzymes such as lipase, chitinase and gelatinase were widespread amongst the Vibrio and Aeromonas isolates. Dominance of V.alginolyticus among the isolates from necrotic larvae and the failure in isolating them from rearing water strongly suggest that they infect larvae and multiply in the larval body and cause mortality in the hatchery. The observation suggested that the isolate V. alginolyticus was a pathogen to the larvae of M.rosenbergii. To sum up, through this work, nine species of Vibrio and genus Aeromonas associated with M.rosenbergii larval rearing systems could be isolated and segregated based on the haemolytic activity and the antibodies (PA bs) for use in diagnosis or epidemiological studies could be produced, based on a virulent culture of V.alginolyticus. This could possibly replace the conventional biochemical tests for identification. As prophylaxis to vibriosis, four isolates of Micrococcus spp. and an isolate of Pseudomonas sp. could be obtained which could possibly be used as antagonistic probiotics in the larval rearing system of M.rosenbergii.
Prajith, K K; Dr.Madhusoodana,Kurup B(Cochin University of Science and Technology, December , 2011)
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Abstract:
In India a study conducted by CIFE and CIBA (1997), concluded that
shrimp farming does more good than harm and it is not eco-unfriendly
(Krishnan and Birthal, 2002). Upsurge in coastal aquaculture activity
induced by high profitability is reported to have caused adverse impacts on
coastal ecosystems and social environments (Parthasarathy and Nirmala,
2000). The crustacean farming sector has received criticism for excessive
use of formulated feed containing high protein, of which around 50% gets
accumulated at the pond bottom as unconsumed (Avnimelech, 1999; Hari
et al., 2004, 2006). The wasted feeds undergo the process of degradation
and results in the release of toxic metabolites to the culture system.
Reduction of protein in the feed, manipulation and utilisation of natural
food in the culture system are the remedy for the above problems. But
before reducing the feed protein, it should be confirmed that the feed with
reduced protein is not affecting the growth and health of the cultured
animal. In the present study, biofloc technology is identified as one of the
innovative technologies for ensuring the ecological and environmental
Sustainability and examines the compatibility of BFT for the sustainable
aquaculture of giant prawn, M. rosenbergii. This thesis starts with a general introduction (Chapter-1), a brief review of the most relevant literature (Chapter-2), results of various experiments (Chapter-3-6), summary (Chapter-7) and recommendations and future research perspectives in the field of biofloc based aquaculture (Chapter – 8). The major objectives of this thesis are, to improve the ecological and economical sustainability of prawn farming by the applicationof BFT and to improve the nutrient utilisation in aquaculture systems.
Description:
School of Industrial Fisheries, Cochin University of Science and Technology
Ravi, Divakaran; Dr.Sivasankara Pillai, V N(Cochin University of Science and Technology, January 15, 2002)
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Abstract:
The most common and conventional method for removing turbidity from
water is by coagulating with alum or iron salts, and settling the precipitate in
suitably designed clarifiers followed by filtration. But the sludge produced is
bulky, difficult to dewater and accumulates in the dumping grounds causing
environmental problems. Synthetic polymers such as polyacrylamide and
polyethyleneoxide have been investigated for their ability to remove turbidity.
They overcome many of the disadvantages of conventional methods, but are
cost—effective only when rapid flocculation and reduction in sludge volume are
demanded. Considering the aforementioned situation, it was felt that more easily
available and eco-friendly materials must be developed for removing turbidity
from water. The results of our studies in this direction are presented in this
thesis. The thesis comprises of nine chapters, with a common bibliography at
the end. Chapter 1 gives an introduction to the nature of turbidity and colour
usually present in water. Chapter 2 discusses the nature and availability of the
principal material used in these studies, namely chitosan. Chapters 3 to 8, which
deal with the actual experimental work, are further subdivided into (a)
introduction, (b) materials and methods, (c) results and discussion and (d)
conclusions. Chapter 9 summarises the entire work so as to put the results and
conclusions into proper perspective.
Description:
School
of Environmental Studies, Cochin University of Science and Technology,
Sini, T K; Dr. Mathew, P T(Central Institute of Fisheries Technology, December , 2007)
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Abstract:
The present study aimed at the utlisation of microbial organisms for the
production of good quality chitin and chitosan. The three strains used for the
study were Lactobacillus plantarum, Lactobacililus brevis and Bacillus subtilis.
These strains were selected on the basis of their acid producing ability to reduce
the pH of the fermenting substrates to prevent spoilage and thus caused
demineralisation of the shell. Besides, the proteolytic enzymes in these strains
acted on proteinaceous covering of shrimp and thus caused deprotenisation of
shrimp shell waste. Thus the two processes involved in chitin production can be
affected to certain extent using bacterial fermentation of shrimp shell.Optimization parameters like fermentation period, quantity of inoculum,
type of sugar, concentration of sugar etc. for fermentation with three different
strains were studied. For these, parameters like pH, Total titrable acidity (TTA),
changes in sugar concentration, changes in microbial count, sensory changes
etc. were studied.Fermentation study with Lactobacillus plantarum was continued with 20%
w/v jaggery broth for 15 days. The inoculum prepared yislded a cell
concentration of approximately 108 CFU/ml. In the present study, lactic acid and
dilute hydrochloric acid were used for initial pH adjustment because; without
adjusting the initial pH, it took more than 5 hours for the lactic acid bacteria to
convert glucose to lactic acid and during this delay spoilage occurred due to
putrefying enzymes active at neutral or higher pH. During the fermentation study,
pH first decreased in correspondence with increase in TTA values. This showed
a clear indication of acid production by the strain. This trend continued till their
proteolytic activity showed an increasing trend. When the available sugar source
started depleting, proteolytic activity also decreased and pH increased. This was
clearly reflected in the sensory evaluation results. Lactic acid treated samples
showed greater extent of demineralization and deprotenisation at the end of
fermentation study than hydrochloric acid treated samples. It can be due to the
effect of strong hydrochloric acid on the initial microbial count, which directly
affects the fermentation process. At the end of fermentation, about 76.5% of ash was removed in lactic acid treated samples and 71.8% in hydrochloric acid
treated samples; 72.8% of proteins in lactic acid treated samples and 70.6% in
hydrochloric acid treated samples.The residual protein and ash in the fermented residue were reduced to
permissible limit by treatment with 0.8N HCI and 1M NaOH. Characteristics of
chitin like chitin content, ash content, protein content, % of N- acetylation etc.
were studied. Quality characteristics like viscosity, degree of deacetylation and
molecular weight of chitosan prepared were also compared. The chitosan
samples prepared from lactic acid treated showed high viscosity than HCI treated
samples. But degree of deacetylation is more in HCI treated samples than lactic
acid treated ones. Characteristics of protein liquor obtained like its biogenic
composition, amino acid composition, total volatile base nitrogen, alpha amino
nitrogen etc. also were studied to find out its suitability as animal feed
supplement.Optimization of fermentation parameters for Lactobacillus brevis
fermentation study was also conducted and parameters were standardized. Then
detailed fermentation study was done in 20%wlv jaggery broth for 17 days. Also
the effect of two different acid treatments (mild HCI and lactic acid) used for initial
pH adjustment on chitin production were also studied. In this study also trend of
changes in pH. changes in sugar concentration ,microbial count changes were
similar to Lactobacillus plantarum studies. At the end of fermentation, residual
protein in the samples were only 32.48% in HCI treated samples and 31.85% in
lactic acid treated samples. The residual ash content was about 33.68% in HCI
treated ones and 32.52% in lactic acid treated ones. The fermented residue was
converted to chitin with good characteristics by treatment with 1.2MNaOH and
1NHCI.Characteristics of chitin samples prepared were studied and extent of Nacetylation
was about 84% in HCI treated chitin and 85%in lactic acid treated
ones assessed from FTIR spectrum. Chitosan was prepared from these samples
by usual chemical method and its extent of solubility, degree of deacetylation,
viscosity and molecular weight etc were studied. The values of viscosity and
molecular weight of the samples prepared were comparatively less than the
chitosan prepared by Lactobacillus plantarum fermentation. Characteristics of protein liquor obtained were analyzed to determine its quality and is suitability as
animal feed supplement.Another strain used for the study was Bacillus subtilis and fermentation
was carried out in 20%w/v jaggery broth for 15 days. It was found that Bacillus
subtilis was more efficient than other Lactobacillus species for deprotenisation
and demineralization. This was mainly due to the difference in the proteolytic
nature of the strains. About 84% of protein and 72% of ash were removed at the
end of fermentation. Considering the statistical significance (P<O.05) in the
extent of demineralization and deproteinisation, we have taken 0.8N HCI for the
demineralization study and 0.6M NaOH for deprotenisation study. Properties of
chitin and chitosan prepared were analyzed and studied.
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
Shalin Saleem; Dr.Sanil Kumar, K V(Cochin University Of Science And Technology, October 16, 2012)
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Abstract:
Satellite remote sensing is being effectively used in monitoring the ocean
surface and its overlying atmosphere. Technical growth in the field of satellite sensors
has made satellite measurement an inevitable part of oceanographic and atmospheric
research. Among the ocean observing sensors, ocean colour sensors make use of
visible band of electromagnetic spectrum (shorter wavelength). The use of shorter
wavelength ensures fine spatial resolution of these parameters to depict oceanographic
and atmospheric characteristics of any region having significant spaio-temporal
variability.
Off the southwest coast of India is such an area showing very significant
spatio-temporal oceanographic and atmospheric variability due to the seasonally
reversing surface winds and currents. Consequently, the region is enriched with
features like upwelling, sinking, eddies, fronts, etc. Among them, upwelling brings
nutrient-rich waters from subsurface layers to surface layers. During this process
primary production enhances, which is measured in ocean colour sensors as high
values of Chl a. Vertical attenuation depth of incident solar radiation (Kd) and Aerosol
Optical Depth (AOD) are another two parameters provided by ocean colour sensors.
Kd is also susceptible to undergo significant seasonal variability due to the changes in
the content of Chl a in the water column. Moreover, Kd is affected by sediment
transport in the upper layers as the region experiences land drainage resulting from
copious rainfall. The wide range of variability of wind speed and direction may also
influence the aerosol source / transport and consequently AOD.
The present doctoral thesis concentrates on the utility of Chl a, Kd and AODprovided by satellite ocean colour sensors to understand oceanographic and
atmospheric variability off the southwest coast of India. The thesis is divided into six
Chapters with further subdivisions
Description:
faculty
of Marine Sciences,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
Paul, A J; Mythili, P; Poulose Jacob,K(Cochin University of Science and Technology, February 10, 2012)
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Abstract:
n the recent years protection of information in digital form is becoming more important. Image and video encryption has applications in various fields including Internet communications, multimedia systems, medical imaging, Tele-medicine and military communications. During storage as well as in transmission, the multimedia information is being exposed to unauthorized entities unless otherwise adequate security measures are built around the information system. There are many kinds of security
threats during the transmission of vital classified information through insecure communication channels. Various encryption schemes are available today to deal with information security issues. Data encryption is widely used to protect sensitive data against the security threat in the form of “attack on confidentiality”. Secure transmission of information through insecure communication channels also requires encryption at the sending side and decryption at the receiving side. Encryption of large text message and image takes time before they can be transmitted, causing considerable delay in
successive transmission of information in real-time. In order to minimize the latency, efficient encryption algorithms are needed. An encryption procedure with adequate security and high throughput is sought in multimedia encryption applications. Traditional symmetric key block ciphers
like Data Encryption Standard (DES), Advanced Encryption Standard (AES) and Escrowed Encryption Standard (EES) are not efficient when the data size is large. With the availability of fast computing tools and communication networks at relatively lower costs today, these encryption standards appear to be not as fast as one would like. High throughput encryption and decryption
are becoming increasingly important in the area of high-speed networking. Fast encryption algorithms are needed in these days for high-speed secure communication of multimedia data. It has been shown that public key algorithms are not a substitute for symmetric-key algorithms. Public key algorithms are slow, whereas symmetric key algorithms generally run much faster. Also, public key systems are vulnerable to chosen plaintext attack.
In this research work, a fast symmetric key encryption scheme, entitled “Matrix Array Symmetric Key (MASK) encryption” based on matrix and array manipulations has been conceived and developed. Fast conversion has been achieved with the use of matrix table look-up substitution, array based transposition and circular shift operations that are performed in the algorithm. MASK encryption is a new concept in symmetric key cryptography. It employs matrix and array manipulation technique using
secret information and data values. It is a block cipher operated on plain text message (or image) blocks of 128 bits using a secret key of size 128 bits producing cipher text message (or cipher image) blocks of the same size. This cipher has two advantages over traditional ciphers. First, the encryption
and decryption procedures are much simpler, and consequently, much faster. Second, the key avalanche effect produced in the ciphertext output is better than that of AES.
Description:
Division of Electronics Engineering, School of Engineering, Cochin University of Science and Technology
Prajith, K K; Dr.Madhusoodana,Kurup B(Cochin University of Science and Technology, December , 2011)
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Abstract:
This thesis Entitled Application of Biofloc technology (BFT) In the Nursery Rearing and Farming of
Giant Freshwater Prawn,Macrobrachium Rosenbergii(De Man). Aquaculture, rearing plants and animals under controlled conditions is growing with an annual growth rate of 8.3% in the period 1970-2008 (FAO, 2010). This trend of growth is essential for the supply of protein-rich food for ever increasing world population. But growth and development of aquaculture should be in sustainable manner, preferably without jeopardizing the aquatic environment.In the present study, the application of BFT in the nursery rearing and farming ofgiant freshwater prawn, M. rosenbergii, is attempted. The result of the study is organised into eight chapters. In the first chapter, the subject is adequately introduced. Various types of aquaculture practices followed, development and status of Indian aquaculture, present status of freshwater pravm culture, BF T and its use for the sustainable aquaculture systems, theory of BFT based aquaculture practices, hypothesis, objective and outline of the thesis are described. An extensive review of literature on studies carried out so far on biofloc based aquaculture are given in chapter 2. The third chapter deals with the application of BFT in the primary nursery phase of freshwater prawn. Several workers suggested the need for an intermediate nursery phase in the culture system of freshwater prawn for the successful production. Thirty day experiment was conducted to study the effect of BFT on the water quality, and animal welfare under the various stocking densities.
The study concluded that stocking finfishes in biofloc-based monoculture system of freshwater prawns has the potential of increasing total yield. Prawns having a higher commercial value than finfishes besides ensuring economic sustainability. Results showed that prawn yield and survival was better in catla dominated tanks. Based on the results of the study, it is recommended to incorporate 25% rohu and 75% catla in the biofloc-based culture system of giant freshwater prawns. The results of the
present study also recommend to stock relatively larger catla for biofloc-based culture system. Fish production was also higher in the 100% catla tank. When catla was added in higher percentages it should ensured that the hiding objects in the culture ponds shall be used in order to reduce the chance of cannibalism among prawns. rohu and catla equally have the ability to harvest the biofloc, catla consumes the planktonic contributes in the floc whereas rohu grazed on the bacterial consortium suspended in the water column. In Chapter 8, recommendations and future research perspectives in
the field of biofloc based aquaculture is presented.
Description:
School of Industrial Fisheries, Cochin University of Science and Technology
Newby, Joseph; Dr.Saramma, A V(Cochin University of Science and Technology, December 28, 2002)
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Abstract:
Aquatic ecosystem in the south west coast of India is noted for its diversity of
habitats. Very often these environments turn bluegreen when the bloom of
bluegreen algae (cyanobacteria) appear consequent to eutrophication. This
phenomenon occursin these habitats one after the other or simultaneously. This
conspicuousness make one curious enough to know more about these nature’s gift
bestowed upon mankind. While persuing the literature on the magnificent flora) it
is understood that it may provide food fertilizer, chemicals and bioactive
substances. These bioactive substances are likely to be involved in regulating
natural populations and are potentially useful as biochemical tools and as
herbicidal or biocontrol agents. The role of cyanobacteria in the aquatic food
chain and contribution in abatement of heavy metals from the natural
environment are well documented. Considering the manifold utilization of the flora and their significance in the food chain, the present investigation has been undertaken
Description:
Department of Marine
Biology, Microbiology and Biochemistry, School of Marine Sciences, Cochin University of Science and Technology
Baiju, K V; Dr. K G K Warrier(National Institute for Interdisciplinary Science and Technology,CSIR, November , 2007)
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Abstract:
The present thesis develops from the point of view of titania sol-gel chemistry and an attempt is made to address the modification of the process for better photoactive titania
by selective doping and also demonstration of utilization of the process for the
preparation of supported membranes and self cleaning films.A general introduction to nanomaterials, nanocrystalline titania and sol-gel
chemistry are presented in the first chapter. A brief and updated literature review on
sol-gel titania, with special emphasis on catalytic and photocatalytic properties and
anatase to rutile transformation are covered. Based on critical assessment of the reported
information the present research problem has been defined.The second chapter describes a new aqueous sol-gel method for the preparation
of nanocrystalline titania using titanyl sulphate as precursor. This approach is novel
since no earlier work has been reported in the same lines proposed here. The sol-gel
process has been followed at each step using particle size, zeta potential measurements
on the sol and thermal analysis of the resultant gel. The prepared powders were then
characterized using X-ray diffraction, FTIR, BET surface area analysis and transmission
electron microscopy.The third chapter presents a detailed discussion on the physico-chemical
characterization of the aqueous sol-gel derived doped titania. The effect of dopants such
as tantalum, gadolinium and ytterbium on the anatase to rutile phase transformation,
surface area as well as their influence on photoactivity is also included.
The fourth chapter demonstrates application of the aqueous sol-gel method in
developing titania coatings on porous alumina substrates for controlling the poresize for
use as membrane elements in ultrafiltration. Thin coatings having ~50 nm thickness and
transparency of ~90% developed on glass surface were tested successfully for self
cleaning applications.
Shaji, P N; Dr.George, Varghese K(Cochin University of Science And Technology, November 5, 2012)
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Abstract:
A study focusing on the identification of return generating factors and to
the extent of their influence on share prices the outcome will be a tool for
investment analysis in the hands of investors portfolio managers and mutual
funds who are mostly concerned with changing share prices. Since the study
takes into account the influence of macroeconomic variables on variations in
share returns by using the outcome the government can frame out suitable
policies on long term basis and that will help in nurturing a healthy economy
and resultant stock market. As every company management tries to maximize
the wealth of the share holders a clear idea about the return generating
variables and their influence will help the management to frame various
policies to maximize the wealth of the shareholders.
Description:
School of Management Studies
Cochin University of Science and Technology
Jessy,John C; Dr.Pillai, R N(Cochin University of Science And Technology, 1985)
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Abstract:
This study is concerned with Autoregressive Moving Average (ARMA) models of time series. ARMA models form a subclass of the class of general linear models which represents stationary time series, a phenomenon encountered most often in practice by engineers, scientists and economists. It is always desirable to employ models which use parameters parsimoniously. Parsimony will be achieved by ARMA models because it has only finite number of parameters. Even though the discussion is primarily concerned with stationary time series, later we will take
up the case of homogeneous non stationary time series which can be transformed to stationary time series. Time series models, obtained with the help of the present and past data is used for forecasting future values. Physical science as well as social science take benefits of forecasting models. The role of forecasting cuts across all fields of management-—finance, marketing, production, business economics, as also in signal process, communication engineering, chemical processes, electronics etc. This high applicability of time series is the motivation to this study.
Description:
Department of mathematics, 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
Ramesh, A; Dr.Madhu, G(Cochin University of Science And Technology, October 18, 2012)
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Abstract:
Cement industry ranks 2nd in energy consumption among the industries
in India. It is one of the major emitter of CO2, due to combustion of fossil fuel
and calcination process. As the huge amount of CO2 emissions cause severe
environment problems, the efficient and effective utilization of energy is a
major concern in Indian cement industry. The main objective of the research
work is to assess the energy cosumption and energy conservation of the Indian
cement industry and to predict future trends in cement production and
reduction of CO2 emissions. In order to achieve this objective, a detailed
energy and exergy analysis of a typical cement plant in Kerala was carried out.
The data on fuel usage, electricity consumption, amount of clinker and cement
production were also collected from a few selected cement industries in India
for the period 2001 - 2010 and the CO2 emissions were estimated. A complete
decomposition method was used for the analysis of change in CO2 emissions
during the period 2001 - 2010 by categorising the cement industries according
to the specific thermal energy consumption. A basic forecasting model for the
cement production trend was developed by using the system dynamic approach
and the model was validated with the data collected from the selected cement
industries. The cement production and CO2 emissions from the industries were
also predicted with the base year as 2010. The sensitivity analysis of the
forecasting model was conducted and found satisfactory. The model was then
modified for the total cement production in India to predict the cement
production and CO2 emissions for the next 21 years under three different
scenarios. The parmeters that influence CO2 emissions like population and
GDP growth rate, demand of cement and its production, clinker consumption
and energy utilization are incorporated in these scenarios. The existing growth
rate of the population and cement production in the year 2010 were used in the
baseline scenario. In the scenario-1 (S1) the growth rate of population was
assumed to be gradually decreasing and finally reach zero by the year 2030,
while in scenario-2 (S2) a faster decline in the growth rate was assumed such
that zero growth rate is achieved in the year 2020. The mitigation strategiesfor the reduction of CO2 emissions from the cement production were identified
and analyzed in the energy management scenarioThe energy and exergy analysis of the raw mill of the cement plant revealed
that the exergy utilization was worse than energy utilization. The energy analysis
of the kiln system showed that around 38% of heat energy is wasted through
exhaust gases of the preheater and cooler of the kiln sysetm. This could be
recovered by the waste heat recovery system. A secondary insulation shell was
also recommended for the kiln in the plant in order to prevent heat loss and
enhance the efficiency of the plant. The decomposition analysis of the change in
CO2 emissions during 2001- 2010 showed that the activity effect was the main
factor for CO2 emissions for the cement industries since it is directly dependent on
economic growth of the country. The forecasting model showed that 15.22% and
29.44% of CO2 emissions reduction can be achieved by the year 2030 in scenario-
(S1) and scenario-2 (S2) respectively. In analysing the energy management
scenario, it was assumed that 25% of electrical energy supply to the cement plants
is replaced by renewable energy. The analysis revealed that the recovery of waste
heat and the use of renewable energy could lead to decline in CO2 emissions 7.1%
for baseline scenario, 10.9 % in scenario-1 (S1) and 11.16% in scenario-2 (S2) in
2030. The combined scenario considering population stabilization by the year
2020, 25% of contribution from renewable energy sources of the cement industry
and 38% thermal energy from the waste heat streams shows that CO2 emissions
from Indian cement industry could be reduced by nearly 37% in the year 2030.
This would reduce a substantial level of greenhouse gas load to the environment.
The cement industry will remain one of the critical sectors for India to meet
its CO2 emissions reduction target. India’s cement production will continue to
grow in the near future due to its GDP growth. The control of population,
improvement in plant efficiency and use of renewable energy are the important
options for the mitigation of CO2 emissions from Indian cement industries
Description:
Division of safety and Fire Engineering,
School of Engineering, Cochin University of Science and Technology
Udayakumar, P; Dr.Ouseph, P P(Cochin University Of Science And Technology, July 19, 2012)
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Abstract:
The nearshore marine ecosystem is a dynamic environment impacted by
many activities, especially the coastal waters and sediments contiguous to major
urban areas. Although heavy metals are natural constituents of the marine
environment, inputs are considered to be conservative pollutants and are
potentially toxic, accumulate in the sediment, are bioconcentrated by organisms
and may cause health problems to humans via the food chain. A variety of
metals in trace amounts are essential for biological processes in all organisms,
but excessive levels can be detrimental by acting as enzyme inhibitors.
Discharge of industrial wastewater, agriculture runoff and untreated sewage
pose a particularly serious threat to the coastal environment of Kerala, but there
is a dearth of studies in documenting the contaminant metals. This study aimed
principally to assess such contamination by examining the results of heavy
metal (Cu, Pb, Cr, Ni, Zn, Cd and Hg) analysis in seawater, sediment and
benthic biota from a survey of five transects along the central and northern
coast of Kerala in 2008 covering a 10.0 km stretch of near shore environment in
each transect. Trophic transfer of metal contaminants from aquatic invertebrates
to its predators was also assessed, by employing a suitable benthic food chain
model in order to understand which all metals are undergoing biotransference
(transfer of metals from a food source to consumer).The study of present contamination levels will be useful for potential
environmental remediation and ecosystem restoration at contaminated sites and
provides a scientific basis for standards and protective measures for the coastal
waters and sediments. The usefulness of biomonitor proposed in this study
would allow identification of different bioavailable metals as well as provide an
assessment of the magnitude of metal contamination in the coastal marine
milieu. The increments in concentration of certain metals between the predator
and prey discerned through benthic food chain can be interpreted as evidence of
biotransference.
Description:
School of Environmental Studies
Cochin University of Science and Technology
Jaison, C A; Dr.Sivanandan, Achari V(Cochin University of Science And Technology, October , 2012)
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Abstract:
Everywhere, on the coastal belt it is proved without doubt that the pristine ground
water quality was severely deteriorated after the 26 December 2004 Indian Ocean
Tsunami. But how far is more relevant, as it is decided by the so-called pre-tsunamic
situation of the region. In water quality studies it is this reference finger print which
earmarks regional ground water chemistry based on which the monthly variability
could rationally be interpreted. This Ph D thesis comprises the testing and evaluation of the facts: whether there is any significant difference in the water quality parameters under study between stations
and between months in Tsunami Affected Dug Wells (TADW). Whether the selected
water quality parameters vary significantly from BIS and WHO standards. Whether
the water quality index (WQI) differ significantly between Tsunami Affected Dug
Wells (TADW) and Bore Wells (BW). Whether there is any significant difference in
the water quality parameters during December 2005 and December 2008. Is there any
significant change in the Water Quality Parameters before 2001 and after tsunami
(2005) in TADW.
Description:
School of Environmental Studies, Cochin University of Science and Technology
Tina,Sebastian; Dr.Sudha Kartha,C; Dr.Vijayakumar, K P(Cochin University of Science & Technology, August , 2009)
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Abstract:
Aim of the present work was to automate CSP process, to deposit and
characterize CuInS2/In2S3 layers using this system and to fabricate devices using
these films.An automated spray system for the deposition of compound
semiconductor thin films was designed and developed so as to eliminate the manual
labour involved in spraying and facilitate standardization of the method. The system
was designed such that parameters like spray rate, movement of spray head, duration
of spray, temperature of substrate, pressure of carrier gas and height of the spray head
from the substrate could be varied. Using this system, binary, ternary as well as
quaternary films could be successfully deposited.The second part of the work deal with deposition and characterization of
CuInS2 and In2S3 layers respectively.In the case of CuInS2 absorbers, the effects of
different preparation conditions and post deposition treatments on the optoelectronic,
morphological and structural properties were investigated. It was observed
that preparation conditions and post deposition treatments played crucial role in controlling the properties of the films. The studies in this direction were useful in
understanding how the variation in spray parameters tailored the properties of the
absorber layer. These results were subsequently made use of in device fabrication
process.Effects of copper incorporation in
In2S3 films were investigated to find how the diffusion of Cu from CuInS2 to In2S3
will affect the properties at the junction. It was noticed that there was a regular
variation in the opto-electronic properties with increase in copper concentration.Devices were fabricated on ITO coated glass using CuInS2 as absorber and
In2S3 as buffer layer with silver as the top electrode. Stable devices could be
deposited over an area of 0.25 cm2, even though the efficiency obtained was not high.
Using manual spray system, we could achieve devices of area 0.01 cm2 only. Thus
automation helped in obtaining repeatable results over larger areas than those
obtained while using the manual unit. Silver diffusion on the cells before coating the
electrodes resulted in better collection of carriers.From this work it was seen CuInS2/In2S3 junction deposited through
automated spray process has potential to achieve high efficiencies.
Description:
Department of Physics,
Cochin University of Science and Technology