Kanakavalli,Susarla S; Dr.Balakrishnan, K P(Cochin University of Science and Technology, March 10, 1987)
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Abstract:
The extraction and use of metals has been the mainstay for the sustained development and progress of a nation. Metals, though fairly stable in the natural environment are found in trace quantities in water bodies. Attention has therefore been focused to identify the metals that impair the water quality. In the last few decades the concern about the fate of these metals in the aquatic system has been gaining momentum, particularly in the industrial belts. The disasters caused by metal poisoning in recent times have prompted an indepth study of the interaction of metals with aquatic biota. Kerala, basically an agriculture oriented state has witnessed the upsurgence of various industries as a part of the nationwide economic development programme. Cochin has been identified as the industrial capital of the state.The present study is an attempt towards a better understanding of the metal-phytoplankton interactions with special reference to the physiological changes in the species. various parameters such as temperature, salinity, pH, nutrients, number of cells, photosynthetic pigments, carbohydrates, protein and lipid are studied to highlight the complexity of metal..phytoplankton interaction
Description:
School of Environmental Studies,
Cochin University of Science and Technology
Dhanya,P R; Dr.Saleena, Mathew(Cochin University of Science And Technology, October 16, 2012)
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Abstract:
Unprocessed seafood harbor high number of bacteria, hence are more prone to
spoilage. In this circumstance, the use of spice in fish for reduction of microorganism can
play an important role in seafood processing. Many essential oils from herbs and spices are
used widely in the food, health and personal care industries and are classified as GRAS
(Generally regarded as safe) substances or are permitted food additives. A large number of
these compounds have been the subject of extensive toxicological scrutiny. However, their
principal function is to impart desirable flavours and aromas and not necessarily to act as
antimicrobial agents. Given the high flavour and aroma impact to plant essential oils, the
future for using these compound as food preservatives lies in the careful selection and
evaluation of their efficacy at low concentrations but in combination with other chemical
preservatives or preservation processes. For this reason they are worth of study alone or in
combination with processing methods in order to establish if they could extend the shelf-life
of foods.
In this study, the effect of the spices, clove, turmeric, cardamom, oregano, rosemary
and garlic in controlling the spoilage and pathogenic bacteria is investigated. Their effect on
biogenic amine formation in tuna especially, histamine, as a result of bacterial control is also
studied in detail. The contribution of spice oleoresin in the sensory and textural parameters
is investigated using textural profile analysis and sensory panel. Finally, the potential of
spices in quality stabilization and in increasing the shelf–life of tuna during frozen storage is
analysed
Description:
School of Industrial Fisheries
Cochin University of Science and Technology
Cilla Abraham; Dr.Radhakrishnan,C K(Cochin University Of Science And Technology, November , 2012)
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Abstract:
The main objective of the present work is to acquire information
regarding the growth responses of P. monodon larvae (from PZ1 upto PL1)
to various mono specific and mixed diets. Evaluate the nutritional quality of
selected species of micro algae viz. Chaetoceros calcitrans, Dunaliella
salina, Isochrysis galbana and Nannochloropsis salina, larvae at three cell concentrations 10x104 cells/ml, 25x104 cells/ml and
50x104 cells/ml.
The P. monodon larvae were transported, at the Nauplius stage, to the
laboratory. The larvae were stocked at density of 150 larvae per litre in 5 litre
FRP tanks with 3 litres of sea water. The algal cell density given to the larvae
varied. The larval stages were fed with increasing densities of algae to
evaluate the relationship between the food densities, ingestion rates,
development and growth of the larvae. The water quality parameters, the
percentage of survival rate, the growth estimation and the algal cell count
were done. Each experiment was carried out in triplicate with a control group
of larvae fed with Chaetoceros calcitrans. For the estimation standard
procedures were used.to P. monodon
Description:
Dept. of Marine Biology,
Microbiology and Biochemistry.
Cochin University of
Science and Technology
Bikash Chandra, Mohapatra; Dr.Rengarajan, K(Cochin University Of Science And Technology, August , 1993)
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Abstract:
The research investigations on pollution, particularly in coastal/
estuarine environments are recent ones and started only in 1970s. Hence
the informations available are fragmentary and scattered. They throw
some light only on either the concentration of heavy metals in water
or in sediment or in organisms. No concerted efforts have been made
to consolidate and correlate the results between the environment and
biota. Literature on the level of concentration of heavy metals in different
tissues of organisms with regard to their availability in the living media,
their ratio, their inter—relationship, tolerance limit of organisms, etc. are
very few or rather nil.
in view of the importance enumerated above, the candidate has
selected the topic "Effects of some heavy metals copper, zinc and lead
on certain tissues of E E (Hamilton and Buchanan) in different
environments" for detailed studies and to understand systematically (i)
the source of effluents and wastes, (ii) the concentration of heavy metals
copper, zinc and lead in water, in sediments and in tissues of the test
animal, (iii) their effects, (iv) capacity of tolerance and accumulation
in different tissues of the animal, and (V) the "Bioaccumulation Factor",
etc.
Description:
Department Of Marine Sciences, Cochin University Of Science And Technology
Ashokakumaran, Unnithan K; Dr.Menon,N R; Dr.Kuttyamma, V J(Cochin University Of Science And Technology, August , 1997)
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Abstract:
The present research programme envisages a comparative study of the effects of
two piscicides of plant origin, viz., mahua oil cake, a derivative from the plant fig
Iatifolia and croton seed, a product from the plant Croton tiglium. Although some reports
on the effects of mahua oil cake and croton seed on fresh water pond culture systems are
available, information on their effect on brackishwater culture systems are rather scanty
This was the guiding principle for launching the present study It is hoped that the findings
will enable aquaculturists to make use of the piscicides in a more rational and efficient
way, and will go a long way towards realising the maximum return liom culture systems
without hampering the environment.
The thesis is presented in seven chapters such as Introduction, Review of
literature, Materials and Methods, Results, Discussion, Summary and Bibliography
Description:
School of Marine Sciences. Cochin University of Science and
Technology
Sebastian, Thomas; Dr.Meera Bai,M(Cochin University of Science And Technology, July , 2013)
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Abstract:
one of the key sectors, identified by the
Department of Industries Government of Kerala, for the cluster development
initiative is Handloom, which gives employment to over over 50,000 people
directly. Despite its age old tradition and fame, the performance of the sector
vis-à-vis power looms is not very rosy owing to (i) competition from cheap
power loom cloth from other states (ii) scarcity of quality yarn (iii) price
escalation of yarn, dyes, chemicals and other raw materials (iv) the shrinking
market for handlooms in Kerala (v) non-demand based production and
inadequacy of new designs and (vi) inefficiencies in the system, particularly in
the co-operative sector. Cluster based approach is adopted in the handloom
sector with the objective of providing necessary support mechanism to come out of the crisis that the sector faces now. While four cluster schemes are being
implemented in Kerala, it is under IHDS-CDP that the State got a sizeable
number of clusters benefiting a large number of societies and weavers- 24
handloom clusters, bringing 152 handloom co-operative societies and over
19,800 handloom workers under the Programme.
This research attempts to revisit the underlying rationale and context of
the new direction and would attempt to broadly analyze the growth trends under
the influence of cluster model adopted by the State IHDS-CDP for the revival
of handloom sector through a detailed study of the handloom co-operative
societies in Kerala. If handloom sector in Kerala can be revived using cluster
based approach, it can be easily concluded that cluster is capable of taking the
MSME in Kerala to a ‘high growth path.’ The study is aimed at understanding
how best clusters emerge as appropriate industrial organization suitable for the
current global structure of manufacture
Description:
Department of Applied Economics,Cochin University Of Science And Technology
Antony,M T; Jose,T Payyappilly(Department of Applied Economics, Faculty of Social Science, February , 1992)
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Abstract:
For the analysis of productivity, capacity utilisation
and profitability the data relating to the manufacturing central
public sector enterprises in Kerala have been collected from the
published annual reports of the companies, public enterprises
surveys of Bureau of Public Enterprises (BPE), Economic Review of
State Planning Board (SPB) and statistical review of central
government enterprises by Centre for Monitoring Indian Economy
(CMIE). Primary data have been collected by conducting personal
interview with the high and middle level executives.
Shahana, T K; Dr.Poulose Jacob, K; Dr.Sreela, Sasi(Cochin University of Science and Technology, October , 2008)
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Abstract:
The thesis focuses on efficient design methods and reconfiguration architectures suitable for higher performance wireless communication .The work presented in this thesis describes the development of compact,inexpensive and low power communication devices that are robust,testable and capable of handling multiple communication standards.A new multistandard Decimation Filter Design Toolbox is developed in MATLAB GUIDE environment.RNS based dual-mode decimation filters reconfigurable for WCDMA/WiMAX and WCDMA/WLANa standards are designed and implemented.It offers high speed operation with lesser area requirement and lower dynamic power dissipation.A novel sigma-delta based direct analog-to-residue converter that reduces the complexity of RNS conversion circuitry is presented.The performance of an OFDM communication system with a new RRNS-convolutional concatenated coding is analysed and improved BER performance is obtained under different channel conditions. Easily testable MAC units for filters are presented using Reed-Muller logic for realization.
Description:
Department of Computer Science,
Cochin University of Science and Technology
Remya, A R; Sreekumar, A(Cochin University of Science and Technology, June , 2014)
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Abstract:
Presently different audio watermarking methods are available; most of them
inclined towards copyright protection and copy protection. This is the key
motive for the notion to develop a speaker verification scheme that guar-
antees non-repudiation services and the thesis is its outcome.
The research presented in this thesis scrutinizes the field of audio water-
marking and the outcome is a speaker verification scheme that is proficient
in addressing issues allied to non-repudiation to a great extent. This work
aimed in developing novel audio watermarking schemes utilizing the fun-
damental ideas of Fast-Fourier Transform (FFT) or Fast Walsh-Hadamard
Transform (FWHT). The Mel-Frequency Cepstral Coefficients (MFCC) the
best parametric representation of the acoustic signals along with few other
key acoustic characteristics is employed in crafting of new schemes. The au-
dio watermark created is entirely dependent to the acoustic features, hence
named as FeatureMark and is crucial in this work.
In any watermarking scheme, the quality of the extracted watermark de-
pends exclusively on the pre-processing action and in this work framing and windowing techniques are involved. The theme non-repudiation provides
immense significance in the audio watermarking schemes proposed in this
work. Modification of the signal spectrum is achieved in a variety of ways
by selecting appropriate FFT/FWHT coefficients and the watermarking
schemes were evaluated for imperceptibility, robustness and capacity char-
acteristics. The proposed schemes are unequivocally effective in terms of
maintaining the sound quality, retrieving the embedded FeatureMark and
in terms of the capacity to hold the mark bits.
Robust nature of these marking schemes is achieved with the help of syn-
chronization codes such as Barker Code with FFT based FeatureMarking
scheme and Walsh Code with FWHT based FeatureMarking scheme. An-
other important feature associated with this scheme is the employment
of an encryption scheme towards the preparation of its FeatureMark that
scrambles the signal features that helps to keep the signal features unreve-
laed.
A comparative study with the existing watermarking schemes and the ex-
periments to evaluate imperceptibility, robustness and capacity tests guar-
antee that the proposed schemes can be baselined as efficient audio water-
marking schemes. The four new digital audio watermarking algorithms in
terms of their performance are remarkable thereby opening more opportu-
nities for further research.
Vimala,George; Jacob, Philip(Department of Electronics, October , 2005)
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Abstract:
The present work is an attempt to probe the elastic properties in some dielectric ceramics, by using ultrasonic pulse echo overlap technique. The base Ba6-xSm8+2xTi18O54 and Ca5Nb2TiO12 are very important dielectrics ceramics used for microwave communication as well as for substrate materials. Ultrasonic is one of the most widely used and powerful techniques to measure elastic properties of solids. The ultrasonic technique is nondestructive in nature and the measurements are relatively straightforward to perform. One unique advantantage of the ultrasonic technique is that both static and dynamic properties can be measured simultaneously. The velocity and attenuation coefficients of the ultrasonic waves propagating through a medium are related to the microscopic structure of the material and they provide valuable information about the structural changes in the system. Among the various ultrasonic techniques, the pulse echo overlap method is the most accurate and precise one. In the present case the decreased elastic properties of Cas-XMg,Nb2TiO12 and Cas-,ZnNb2TiO12 ceramics can be attributed to their mixture phases beyond x = 1. Moreover, the abrupt change in elastic properties observed for x >1 can also be correlated to the structural transformation of the materials from their phase pure form to mixture phases for higher extent of substitution of the concerned material . Ca4(ANb2Ti)012 (A = Mg, Zn) is the strongest compound with the maximum values for elastic properties . This could be due to the possible substitution of Mg/Zn ions with lesser radius [25] than Ca2+ in perovskite B-site of Ca(Cali4Nb2i4Tili4) O3 material to contribute more ordering and symmetry to the system [20]. All other compositions (x > 1) contain mixed-phases and for such mixed-phase samples, the mechanical properties are difficult to explain.
Rajeev, Kumar K; Dr.Sathianandan, K(Cochin University of Science and Technology, June 20, 1989)
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Abstract:
A brief account of the several methods used for the production of thin films is presented in this Chapter. The discussions stress on the important methods used for the fabrication of a-si:H thin films. This review' also reveals ‘that almost all the general methods, like vacuum evaporation, sputtering,
glow discharge and even chemical methods are currently employed for the production of a-Si:H thin films. Each method has its own advantages and disadvantages. However, certain methods are generally preferred. Subsequently a detailed account of the method used here for the preparation of amorphous silicon thin films and their hydrogenation is presented. The metal chamber used for the electrical and dielectric measurements is also described. A brief mention is made-on the electrode
structure, film area and film geometry.
Description:
Division of Thin Film, Department
of Physics, Cochin University of Science and Technology