Neelakandan Namboodiripad, K S; Dr.Kurup, P G(Cochin University of Science And Technology, March , 1984)
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Abstract:
The results of an investigation on the limits of the random errors contained in the basic data of Physical Oceanography and their propagation through the computational procedures are presented in this thesis. It also suggest a method which increases the reliability of the derived
results. The thesis is presented in eight chapters including the introductory chapter. Chapter 2 discusses the general theory of errors that are relevant in the context of the propagation of errors in Physical Oceanographic computations. The error components contained in the independent oceanographic variables namely, temperature, salinity and depth are deliniated and quantified in chapter 3. Chapter 4 discusses and derives the magnitude of errors in the computation of the
dependent oceanographic variables, density in situ, gt, specific volume and specific volume anomaly, due to the propagation of errors contained in the independent oceanographic variables. The errors propagated into the computed values of the derived quantities namely, dynamic
depth and relative currents, have been estimated and presented chapter 5. Chapter 6 reviews the existing methods for the identification of level of no motion and suggests a method for the identification of a reliable zero reference level. Chapter 7 discusses the available methods for the extension of the zero reference level into shallow regions of the oceans and suggests a new method which is more reliable. A procedure of graphical smoothening of dynamic topographies between the error limits to provide more reliable results is also suggested in this chapter. Chapter 8 deals with the computation of the geostrophic current from these smoothened values of
dynamic heights, with reference to the selected zero reference level. The summary and conclusion are also presented in this chapter.
Description:
School of marine sciences, Cochin University of Science And Technology
John Chellappan, N; Ramachandran, A(School of Industrial Fisheries, 2004)
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Abstract:
In this study the quality and process control factors during the production and storage of salted dried fish products. The study reveals that quantity of dry fish production in the state is decreasing and dry fish processing industry should be encouraged by central and state governments. The dry and wet salting may be carried out to a period of 4 to 8 hours respectively and time may depend on temperature, size, and concentration of medium. Demand is an unavoidable factor for sale of fish. The packed dry salted lots kept at room temperature are useful only for 20 days. The refrigerator- stored lots had more storage life and nutritional content are good up to 3 months. The cold storage stored dry salted lot had more storage life than the wet salted lot. The use of preservatives in salting is encouraged to reduce pH. The low temperature preservation maintains the nutritional value and quality for long period. It further encourages the labeling of nutritional value of dry fish as in tinned products.
Roy, Thomas M; Dr.Benny Mathews, Abraham(Cochin University of Science & Technology, August , 2009)
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Abstract:
The present study focused on the quality of rainwater at various land use
locations and its variations on interaction with various domestic rainwater
harvesting systems.Sampling sites were selected based upon the land use
pattern of the locations and were classified as rural, urban, industrial and
sub urban. Rainwater samples were collected from the south west monsoon of
May 2007 to north east monsoon of October 2008, from four sampling sites namely Kothamangalam, Emakulam, Eloor and Kalamassery, in Ernakulam
district of the State of Kerala, which characterized typical rural, urban,
industrial and suburban locations respectively. Rain water samples at various
stages of harvesting were also collected. The samples were analyzed according
to standard procedures and their physico-chemical and microbiological
parameters were determined. The variations of the chemical composition of the rainwater collected
were studied using statistical methods. It was observed that 17.5%, 30%,
45.8% and 12.1% of rainwater samples collected at rural, urban, industrial and
suburban locations respectively had pH less than 5.6, which is considered as
the pH of cloud water at equilibrium with atmospheric CO,.Nearly 46% of the
rainwater samples were in acidic range in the industrial location while it was
only 17% in the rural location. Multivariate statistical analysls was done using
Principal Component Analysis, and the sources that inf1uence the composition
of rainwater at each locations were identified .which clearly indicated that the
quality of rain water is site specific and represents the atmospheric
characteristics of the free fall The quality of harvested rainwater showed significant variations at
different stages of harvesting due to deposition of dust from the roof
catchment surface, leaching of cement constituents etc. Except the micro
biological quality, the harvested rainwater satisfied the Indian Standard guide
lines for drinking water. Studies conducted on the leaching of cement
constituents in water concluded that tanks made with ordinary portland cement
and portland pozzolana cement could be safely used for storage of rain water.
Description:
School of Engineering, Cochin University of Science and Technology
Jayasankar, P; Dr.Alagarswami, K(Cochin University Of Science And Technology, June , 1989)
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Abstract:
From the point of view of rational exploitation and proper management
of the fishery resources as well as for the development of intensive aquaculture
of fishes through selective breeding, brood stock development, domestication
and genetic improvement, a sound knowledge of reproductive biology and
physiology of the candidate species is of great importance. In recent times, a
wealth of information on maturity, spawning habits, spawning periodicity, spawning
season, size at maturity and fecundity of commercially important fishes
has been generated.
Gametogenesis involves the transformation of Primordial germ cells in
the gonads into specialised cells or gametes, namely ova in the female and
sperms in male, through a series of complex morphological and cytological
events. The formation of male gamete is known as spermatogenesis. In the
female, the primary growth phase involving the formation of primary oocyte
from oogonia is known as oogenesis, which would be followed by the secondary
growth phase, in which considerable increase in the size of the oocyte occurs,
due mainly to accumulation of yolk. This process is known as vitellogenesis,
which would be followed by final maturation and ovulation of the ova.
In the present work, basic aspects of maturation and spawning, salient
features of gametogenesis and associated biochemical changes occurring during
these processes in an important cultivable fish, Sillago sihama belonging to
the family Sillaginidae have been investigated.
Description:
Department of Marine Sciences,Cochin University Of Science And Technology
Sunilkumar, Mohamed K; Dr.Diwan, A D(Cochin University of Science and Technology, June , 1989)
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Abstract:
The present investigation has been carried out to understand the process and events leading to maturation of the ovary and testis in the Indian white prawn Penaeus indicus. The study includes the classification of the ovarian maturity stages based on its colour, gonadosomatic index, oocyte diameter and morphological changes in the oocyte. Further the process of oogenesis has been investigated using light and electron microscopic techniques. A histochemical study of the ovary has also been carried out to determine the sequence in which yolk substances are synthesized or sequestered in the oocytes and also to elicit the nature of the penaeid yolk material. The process of spermatogenesis and the development of the spermatophore has been studied in detail using light and electron microscopic methods. In addition a brief histochemical study on the testis was also made to understand the nature of the organic reserves in the sperm cells.
Description:
Centre of Advanced Studies in Mariculture,
Central Marine Fisheries Research Institute
Kuldeep, Lal Kumar; Dr.James, P S B R(Cochin University of Science And Technology, July , 1991)
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Abstract:
At present, there is paucity of information regarding the breeding
biology, especially from southeastern region, which differs in its climatic
features from northeastern coastal areas, where some attempts have been
made to study the biology of the fish, though not documented in detail
(Jhingran and Natarajan, I969; Patnaik and Jena, 1976; Kowtal, 1977; Roy
e_t _a_l_., I977). The present work, first to undertake detailed investigation
into reproductive aspects of the fish from India is not only confined to
biology, but extend to the study on histological as well as physiological
changes in the processes associated with natural reproductive cycle. The
main objective of the study is to develop a background for the standardisation
of subsequent artificial propagation techniques for the Sea Dass
The thesis is presented in three chapters. The first chapter; general introduction, surveys the literature pertaining to the status of research on Lates calcarifer with specific reference to reproduction and acquaculture. The second chapter entitled, materials and methods gives description regarding collection of specimens as well as samples in addition to the various analytical methodologies employed during the study.
Description:
School of marine sciences, Central institute of fisheries technology, Cochin University of Science And Technology
Sivachandrabose, K; Dr.Suseelan, C(Cochin University of Science and Technology, October 10, 1995)
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Abstract:
A study of the reproductive physiology of P. (P). semisulcatus wasundertaken as this information is an essential prerequisite for brood stock development for hatchery operations, and the results are embodied in this thesis. The thesis is presented in seven chapters. The protein, lipid and carbohydrate contents of ovary were estimated for the different vitellogenic phases. The protein, lipid, carbohydrate and cholesterol contents were estimated in testes and spermatophore.The thesis present the results of induced maturation experiments by eyestalk ablation, CNS extract injection and UV rays application on immature female prawns.
Latex waste products contain rubber hydrocarbon of very high
quality, which is only lightly cross linked. Selected wastes such as thread waste
and glove waste were modified into processable materials by a novel economic
process and thermoplastic elastomers were prepared by blending these modified
waste materials with high density polyethylene in various proportions. The
mechanical properties as well as the rheological behaviour of these blends were
evaluated and compared with those of the natural rubber-high density
polyethylene blends.
Murthy,P G K; Dr.Sharma,G S(Cochin University of Science and Technology, October , 1986)
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Abstract:
The thesis entitled Studies on Thermal Structure in the Seas Around India. An attempt is made in this study to document the observed variability of thermal structure, both on seasonal and short-term scales, in the eastern Arabian Sea and southwestern Bay of Bengal, from the spatial and time series data sets from a reasonably strong data base. The present study has certain limitations. The mean temperatures are based on an uneven distribution of data in space and time. Some of the areas, although having a ‘full annual coverage, do not have adequate data for some months. Some portions in the area under study are having data gaps. The consistency and the coherence in the internal wave characteristics could not be examined due to non-availability of adequate data sets. The influence of generating mechanisms; other than winds and tides on the observed internal wave fields could not be ascertained due to lack of data. However, a comprehensive and intensive data collection can overcome these limitations. The deployment of moored buoys with arrays of sensors at different depths at some important locations for about 5 to 10 years can provide intensive and extensive data sets. This strong data base can afford to address the short-term and seasonal variability of thermal field and understand in detail the individual and collective influences of various physical and dynamical mechanisms
responsible for such variability.
Latex waste like glove waste was effectively modified using a new reclaiming
agent, thiocarbanilide. This modified waste was blended with linear low-density
polyethylene (LLDPE) to develop a novel thermoplastic elastomer. Both uncrosslinked
and dynamically crosslinked blends were prepared and their properties
were studied. The results were found to be comparable to those of conventional
thermoplastic elastomers.
Ivy, Mathew; Dr.Joseph,Francis D(Cochin University Of Science And Technology, August 20, 1992)
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Abstract:
Thermoplastic elastomers are a relatively new
class of materials which compete with thermoset rubbers in
some areas and thermoplastic materials in other areas. The
main thrust of the present investigation is a comparative
study’ on commercially .available triblock. styrene thermoplastic
elastomers and those derived from blends of
acrylonitrile-butadiene rubber and poly(vinyl chloride).
The styrene—based thermoplastic elastomers are gaining
acceptance as a replacement for both natural and synthetic
rubber‘ in many‘ applications. TPEs based on blends of
elastomers and plastics ix: the fastest growing segment of
the broad class of thermoplastic elastomers. Broad
applicability and simple technology of production are the
attractive features of this class of TPES. NBR/PVC thermoplastic
elastomers were selected for this investigation due
to the versatility of PVC, its number one position, low
cost. ability to Ina compounded into various flexible and
rigid form with good physical and chemical and weathering
properties etc., which will be passed over to PVC blends
especially NBR/PVC blends which are known to form miscible
systems
Description:
Department of Polymer Science and Rubber
Technology, Cochin University of Science and Technology
Lizen, Mathews; Dr.Chandramohanakumar, N(Department of Chemical Oceanography, School of Marine Sciences, 2000)
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Abstract:
In the present study the nutrient dynamics and fertility of Kuttanad waters is addressed. Kuttanad represent a wetland system with considerable agricultural activities. The hydrographical features of the Kuttanad waters are controlled by discharges from Manimala, Meenachil, Pamba, Achencoil and Muvattupuzha rivers and also by tidal intrusions of saline waters from Cochin backwaters during summers. The fertility of these water bodies were significantly high and supported good agricultural production. Kuttanad water forms the southern part of this aquatic systems and is considered as the most productive zones. As a part of the management scheme for a higher agricultural activity, the Thannermukkam bund was constructed to block and regulate the intrusion of saline water. The increased use of artificial fertilizers along with stagnant character of the water body in this area has resulted in sharp decline in the water quality, productivity and aquatic resources.
Lizen, Mathews; Dr.Chandramohanakumar, N(Cochin University of Science and Technology, January , 2000)
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Abstract:
In the present study the nutrient dynamics and fertility of Kuttanad waters is addressed. Kuttanad represent a wetland system with considerable agricultural activities. The hydrographical features of the Kuttanad waters are controlled by discharges from Manimala, Meenachil, Pamba, Achencoil and Muvattupuzha rivers and also by tidal intrusions of saline waters from Cochin backwaters during summers. The fertility of these water bodies were significantly high and supported good agricultural production. Kuttanad water forms the southern part of this aquatic systems and is considered as the most productive zones. As a part of the management scheme for a higher agricultural activity, the Thannermukkam bund was constructed to block and regulate the intrusion of saline water. The increased use of artificial fertilizers along with stagnant character of the water body in this area has resulted in sharp decline in the water quality, productivity and aquatic resources.
Prasanth A, Pillai; Dr.Mohan Kumar, K(Cochin University of Science & Technology, October , 2008)
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Abstract:
The present study illustrates the biennial oscillation in different ocean-atmosphere
parameters associated with interannual variability of Indian summer monsoon rainfall.It also accounts the role of different processes like ENSO, IOD, QBO and ISO in the monsoon variability during the TBO years.
Description:
Department of Atmospheric Sciences,
Cochin University of Science and Technology